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-rw-r--r--html/baremetal/101screen.subx.html2
-rw-r--r--html/baremetal/102keyboard.subx.html2
-rw-r--r--html/baremetal/103grapheme.subx.html184
-rw-r--r--html/baremetal/106stream.subx.html137
-rw-r--r--html/baremetal/108write.subx.html4
-rw-r--r--html/baremetal/112read-byte.subx.html2
-rw-r--r--html/baremetal/115write-byte.subx.html2
-rw-r--r--html/baremetal/120allocate.subx.html2
-rw-r--r--html/baremetal/302stack_allocate.subx.html4
-rw-r--r--html/baremetal/309stream.subx.html2
-rw-r--r--html/baremetal/313index-bounds-check.subx.html4
-rw-r--r--html/baremetal/400.mu.html21
-rw-r--r--html/baremetal/403unicode.mu.html16
-rw-r--r--html/baremetal/501draw-text.mu.html280
-rw-r--r--html/baremetal/502manhattan-line.mu.html89
-rw-r--r--html/baremetal/boot.hex.html2
-rw-r--r--html/baremetal/boot0.hex.html2
-rw-r--r--html/baremetal/ex2.mu.html8
-rw-r--r--html/baremetal/ex3.mu.html8
-rw-r--r--html/baremetal/ex4.mu.html8
-rw-r--r--html/baremetal/ex5.mu.html37
-rw-r--r--html/baremetal/ex6.mu.html94
22 files changed, 762 insertions, 148 deletions
diff --git a/html/baremetal/101screen.subx.html b/html/baremetal/101screen.subx.html
index df52a5b8..038e8f78 100644
--- a/html/baremetal/101screen.subx.html
+++ b/html/baremetal/101screen.subx.html
@@ -15,8 +15,8 @@ body { font-size:12pt; font-family: monospace; color: #000000; background-color:
 a { color:inherit; }
 * { font-size:12pt; font-size: 1em; }
 .subxComment { color: #005faf; }
-.LineNr { }
 .subxS1Comment { color: #0000af; }
+.LineNr { }
 .subxFunction { color: #af5f00; text-decoration: underline; }
 .Constant { color: #008787; }
 -->
diff --git a/html/baremetal/102keyboard.subx.html b/html/baremetal/102keyboard.subx.html
index f841e696..cc092133 100644
--- a/html/baremetal/102keyboard.subx.html
+++ b/html/baremetal/102keyboard.subx.html
@@ -15,8 +15,8 @@ body { font-size:12pt; font-family: monospace; color: #000000; background-color:
 a { color:inherit; }
 * { font-size:12pt; font-size: 1em; }
 .subxComment { color: #005faf; }
-.LineNr { }
 .subxS1Comment { color: #0000af; }
+.LineNr { }
 .subxFunction { color: #af5f00; text-decoration: underline; }
 .Constant { color: #008787; }
 -->
diff --git a/html/baremetal/103grapheme.subx.html b/html/baremetal/103grapheme.subx.html
index b34168d6..13dc6073 100644
--- a/html/baremetal/103grapheme.subx.html
+++ b/html/baremetal/103grapheme.subx.html
@@ -14,9 +14,10 @@ pre { white-space: pre-wrap; font-family: monospace; color: #000000; background-
 body { font-size:12pt; font-family: monospace; color: #000000; background-color: #c6c6c6; }
 a { color:inherit; }
 * { font-size:12pt; font-size: 1em; }
+.SpecialChar { color: #d70000; }
 .subxComment { color: #005faf; }
-.LineNr { }
 .subxS1Comment { color: #0000af; }
+.LineNr { }
 .subxFunction { color: #af5f00; text-decoration: underline; }
 .Constant { color: #008787; }
 -->
@@ -54,76 +55,117 @@ if ('onhashchange' in window) {
 <body onload='JumpToLine();'>
 <a href='https://github.com/akkartik/mu/blob/main/baremetal/103grapheme.subx'>https://github.com/akkartik/mu/blob/main/baremetal/103grapheme.subx</a>
 <pre id='vimCodeElement'>
-<span id="L1" class="LineNr"> 1 </span><span class="subxFunction">draw-grapheme</span>:  <span class="subxComment"># screen: (addr screen), g: grapheme, x: int, y: int, color: int</span>
-<span id="L2" class="LineNr"> 2 </span>    <span class="subxS1Comment"># . prologue</span>
-<span id="L3" class="LineNr"> 3 </span>    55/push-ebp
-<span id="L4" class="LineNr"> 4 </span>    89/&lt;- %ebp 4/r32/esp
-<span id="L5" class="LineNr"> 5 </span>    <span class="subxS1Comment"># . save registers</span>
-<span id="L6" class="LineNr"> 6 </span>    50/push-eax
-<span id="L7" class="LineNr"> 7 </span>    51/push-ecx
-<span id="L8" class="LineNr"> 8 </span>    52/push-edx
-<span id="L9" class="LineNr"> 9 </span>    53/push-ebx
-<span id="L10" class="LineNr">10 </span>    56/push-esi
-<span id="L11" class="LineNr">11 </span>    <span class="subxComment"># var letter-bitmap/esi = font[g]</span>
-<span id="L12" class="LineNr">12 </span>    8b/-&gt; *(ebp+0xc) 6/r32/esi
-<span id="L13" class="LineNr">13 </span>    c1 4/subop/shift-left %esi 4/imm8
-<span id="L14" class="LineNr">14 </span>    8d/copy-address *(esi+0x8800) 6/r32/esi  <span class="subxComment"># font-start</span>
-<span id="L15" class="LineNr">15 </span>    <span class="subxComment"># if (letter-bitmap &gt;= 0x9000) return  # characters beyond ASCII currently not supported</span>
-<span id="L16" class="LineNr">16 </span>    81 7/subop/compare %esi 0x9000/imm32
-<span id="L17" class="LineNr">17 </span>    7d/jump-if-&gt;= $draw-grapheme:end/disp8
-<span id="L18" class="LineNr">18 </span>    <span class="subxComment"># edx = y</span>
-<span id="L19" class="LineNr">19 </span>    8b/-&gt; *(ebp+0x14) 2/r32/edx
-<span id="L20" class="LineNr">20 </span>    <span class="subxComment"># var ymax/ebx: int = y + 16</span>
-<span id="L21" class="LineNr">21 </span>    8b/-&gt; *(ebp+0x14) 3/r32/ebx
-<span id="L22" class="LineNr">22 </span>    81 0/subop/add %ebx 0x10/imm32
-<span id="L23" class="LineNr">23 </span>    {
-<span id="L24" class="LineNr">24 </span>      <span class="subxComment"># if (y &gt;= ymax) break</span>
-<span id="L25" class="LineNr">25 </span>      39/compare %edx 3/r32/ebx
-<span id="L26" class="LineNr">26 </span>      7d/jump-if-&gt;= <span class="Constant">break</span>/disp8
-<span id="L27" class="LineNr">27 </span>      <span class="subxComment"># eax = x + 7</span>
-<span id="L28" class="LineNr">28 </span>      8b/-&gt; *(ebp+0x10) 0/r32/eax
-<span id="L29" class="LineNr">29 </span>      81 0/subop/add %eax 7/imm32
-<span id="L30" class="LineNr">30 </span>      <span class="subxComment"># var xmin/ecx: int = x</span>
-<span id="L31" class="LineNr">31 </span>      8b/-&gt; *(ebp+0x10) 1/r32/ecx
-<span id="L32" class="LineNr">32 </span>      <span class="subxComment"># var row-bitmap/ebx: int = *letter-bitmap</span>
-<span id="L33" class="LineNr">33 </span>      53/push-ebx
-<span id="L34" class="LineNr">34 </span>      8b/-&gt; *esi 3/r32/ebx
-<span id="L35" class="LineNr">35 </span>      {
-<span id="L36" class="LineNr">36 </span>        <span class="subxComment"># if (x &lt; xmin) break</span>
-<span id="L37" class="LineNr">37 </span>        39/compare %eax 1/r32/ecx
-<span id="L38" class="LineNr">38 </span>        7c/jump-if-&lt; <span class="Constant">break</span>/disp8
-<span id="L39" class="LineNr">39 </span>        <span class="subxComment"># shift LSB from row-bitmap into carry flag (CF)</span>
-<span id="L40" class="LineNr">40 </span>        c1 5/subop/shift-right-logical %ebx 1/imm8
-<span id="L41" class="LineNr">41 </span>        <span class="subxComment"># if LSB, draw a pixel</span>
-<span id="L42" class="LineNr">42 </span>        {
-<span id="L43" class="LineNr">43 </span>          73/jump-if-not-CF <span class="Constant">break</span>/disp8
-<span id="L44" class="LineNr">44 </span>          (<a href='101screen.subx.html#L3'>pixel</a> *(ebp+8) %eax %edx *(ebp+0x18))
-<span id="L45" class="LineNr">45 </span>        }
-<span id="L46" class="LineNr">46 </span>        <span class="subxComment"># --x</span>
-<span id="L47" class="LineNr">47 </span>        48/decrement-eax
-<span id="L48" class="LineNr">48 </span>        <span class="subxComment">#</span>
-<span id="L49" class="LineNr">49 </span>        eb/jump <span class="Constant">loop</span>/disp8
-<span id="L50" class="LineNr">50 </span>      }
-<span id="L51" class="LineNr">51 </span>      <span class="subxComment"># reclaim row-bitmap</span>
-<span id="L52" class="LineNr">52 </span>      5b/pop-to-ebx
-<span id="L53" class="LineNr">53 </span>      <span class="subxComment"># ++y</span>
-<span id="L54" class="LineNr">54 </span>      42/increment-edx
-<span id="L55" class="LineNr">55 </span>      <span class="subxComment"># next bitmap row</span>
-<span id="L56" class="LineNr">56 </span>      46/increment-esi
-<span id="L57" class="LineNr">57 </span>      <span class="subxComment">#</span>
-<span id="L58" class="LineNr">58 </span>      eb/jump <span class="Constant">loop</span>/disp8
-<span id="L59" class="LineNr">59 </span>    }
-<span id="L60" class="LineNr">60 </span><span class="Constant">$draw-grapheme:end</span>:
-<span id="L61" class="LineNr">61 </span>    <span class="subxS1Comment"># . restore registers</span>
-<span id="L62" class="LineNr">62 </span>    5e/pop-to-esi
-<span id="L63" class="LineNr">63 </span>    5b/pop-to-ebx
-<span id="L64" class="LineNr">64 </span>    5a/pop-to-edx
-<span id="L65" class="LineNr">65 </span>    59/pop-to-ecx
-<span id="L66" class="LineNr">66 </span>    58/pop-to-eax
-<span id="L67" class="LineNr">67 </span>    <span class="subxS1Comment"># . epilogue</span>
-<span id="L68" class="LineNr">68 </span>    89/&lt;- %esp 5/r32/ebp
-<span id="L69" class="LineNr">69 </span>    5d/pop-to-ebp
-<span id="L70" class="LineNr">70 </span>    c3/return
+<span id="L1" class="LineNr">  1 </span><span class="subxFunction">draw-grapheme</span>:  <span class="subxComment"># screen: (addr screen), g: grapheme, x: int, y: int, color: int</span>
+<span id="L2" class="LineNr">  2 </span>    <span class="subxS1Comment"># . prologue</span>
+<span id="L3" class="LineNr">  3 </span>    55/push-ebp
+<span id="L4" class="LineNr">  4 </span>    89/&lt;- %ebp 4/r32/esp
+<span id="L5" class="LineNr">  5 </span>    <span class="subxS1Comment"># . save registers</span>
+<span id="L6" class="LineNr">  6 </span>    50/push-eax
+<span id="L7" class="LineNr">  7 </span>    51/push-ecx
+<span id="L8" class="LineNr">  8 </span>    52/push-edx
+<span id="L9" class="LineNr">  9 </span>    53/push-ebx
+<span id="L10" class="LineNr"> 10 </span>    56/push-esi
+<span id="L11" class="LineNr"> 11 </span>    <span class="subxComment"># TODO: support fake screen; we currently assume 'screen' is always 0 (real)</span>
+<span id="L12" class="LineNr"> 12 </span>    <span class="subxComment"># var letter-bitmap/esi = font[g]</span>
+<span id="L13" class="LineNr"> 13 </span>    8b/-&gt; *(ebp+0xc) 6/r32/esi
+<span id="L14" class="LineNr"> 14 </span>    c1 4/subop/shift-left %esi 4/imm8
+<span id="L15" class="LineNr"> 15 </span>    8d/copy-address *(esi+0x8800) 6/r32/esi  <span class="subxComment"># font-start</span>
+<span id="L16" class="LineNr"> 16 </span>    <span class="subxComment"># if (letter-bitmap &gt;= 0x9000) return  # characters beyond ASCII currently not supported</span>
+<span id="L17" class="LineNr"> 17 </span>    81 7/subop/compare %esi 0x9000/imm32
+<span id="L18" class="LineNr"> 18 </span>    7d/jump-if-&gt;= $draw-grapheme:end/disp8
+<span id="L19" class="LineNr"> 19 </span>    <span class="subxComment"># edx = y</span>
+<span id="L20" class="LineNr"> 20 </span>    8b/-&gt; *(ebp+0x14) 2/r32/edx
+<span id="L21" class="LineNr"> 21 </span>    <span class="subxComment"># var ymax/ebx: int = y + 16</span>
+<span id="L22" class="LineNr"> 22 </span>    8b/-&gt; *(ebp+0x14) 3/r32/ebx
+<span id="L23" class="LineNr"> 23 </span>    81 0/subop/add %ebx 0x10/imm32
+<span id="L24" class="LineNr"> 24 </span>    {
+<span id="L25" class="LineNr"> 25 </span>      <span class="subxComment"># if (y &gt;= ymax) break</span>
+<span id="L26" class="LineNr"> 26 </span>      39/compare %edx 3/r32/ebx
+<span id="L27" class="LineNr"> 27 </span>      7d/jump-if-&gt;= <span class="Constant">break</span>/disp8
+<span id="L28" class="LineNr"> 28 </span>      <span class="subxComment"># eax = x + 7</span>
+<span id="L29" class="LineNr"> 29 </span>      8b/-&gt; *(ebp+0x10) 0/r32/eax
+<span id="L30" class="LineNr"> 30 </span>      81 0/subop/add %eax 7/imm32
+<span id="L31" class="LineNr"> 31 </span>      <span class="subxComment"># var xmin/ecx: int = x</span>
+<span id="L32" class="LineNr"> 32 </span>      8b/-&gt; *(ebp+0x10) 1/r32/ecx
+<span id="L33" class="LineNr"> 33 </span>      <span class="subxComment"># var row-bitmap/ebx: int = *letter-bitmap</span>
+<span id="L34" class="LineNr"> 34 </span>      53/push-ebx
+<span id="L35" class="LineNr"> 35 </span>      8b/-&gt; *esi 3/r32/ebx
+<span id="L36" class="LineNr"> 36 </span>      {
+<span id="L37" class="LineNr"> 37 </span>        <span class="subxComment"># if (x &lt; xmin) break</span>
+<span id="L38" class="LineNr"> 38 </span>        39/compare %eax 1/r32/ecx
+<span id="L39" class="LineNr"> 39 </span>        7c/jump-if-&lt; <span class="Constant">break</span>/disp8
+<span id="L40" class="LineNr"> 40 </span>        <span class="subxComment"># shift LSB from row-bitmap into carry flag (CF)</span>
+<span id="L41" class="LineNr"> 41 </span>        c1 5/subop/shift-right-logical %ebx 1/imm8
+<span id="L42" class="LineNr"> 42 </span>        <span class="subxComment"># if LSB, draw a pixel</span>
+<span id="L43" class="LineNr"> 43 </span>        {
+<span id="L44" class="LineNr"> 44 </span>          73/jump-if-not-CF <span class="Constant">break</span>/disp8
+<span id="L45" class="LineNr"> 45 </span>          (<a href='101screen.subx.html#L3'>pixel</a> *(ebp+8) %eax %edx *(ebp+0x18))
+<span id="L46" class="LineNr"> 46 </span>        }
+<span id="L47" class="LineNr"> 47 </span>        <span class="subxComment"># --x</span>
+<span id="L48" class="LineNr"> 48 </span>        48/decrement-eax
+<span id="L49" class="LineNr"> 49 </span>        <span class="subxComment">#</span>
+<span id="L50" class="LineNr"> 50 </span>        eb/jump <span class="Constant">loop</span>/disp8
+<span id="L51" class="LineNr"> 51 </span>      }
+<span id="L52" class="LineNr"> 52 </span>      <span class="subxComment"># reclaim row-bitmap</span>
+<span id="L53" class="LineNr"> 53 </span>      5b/pop-to-ebx
+<span id="L54" class="LineNr"> 54 </span>      <span class="subxComment"># ++y</span>
+<span id="L55" class="LineNr"> 55 </span>      42/increment-edx
+<span id="L56" class="LineNr"> 56 </span>      <span class="subxComment"># next bitmap row</span>
+<span id="L57" class="LineNr"> 57 </span>      46/increment-esi
+<span id="L58" class="LineNr"> 58 </span>      <span class="subxComment">#</span>
+<span id="L59" class="LineNr"> 59 </span>      eb/jump <span class="Constant">loop</span>/disp8
+<span id="L60" class="LineNr"> 60 </span>    }
+<span id="L61" class="LineNr"> 61 </span><span class="Constant">$draw-grapheme:end</span>:
+<span id="L62" class="LineNr"> 62 </span>    <span class="subxS1Comment"># . restore registers</span>
+<span id="L63" class="LineNr"> 63 </span>    5e/pop-to-esi
+<span id="L64" class="LineNr"> 64 </span>    5b/pop-to-ebx
+<span id="L65" class="LineNr"> 65 </span>    5a/pop-to-edx
+<span id="L66" class="LineNr"> 66 </span>    59/pop-to-ecx
+<span id="L67" class="LineNr"> 67 </span>    58/pop-to-eax
+<span id="L68" class="LineNr"> 68 </span>    <span class="subxS1Comment"># . epilogue</span>
+<span id="L69" class="LineNr"> 69 </span>    89/&lt;- %esp 5/r32/ebp
+<span id="L70" class="LineNr"> 70 </span>    5d/pop-to-ebp
+<span id="L71" class="LineNr"> 71 </span>    c3/return
+<span id="L72" class="LineNr"> 72 </span>
+<span id="L73" class="LineNr"> 73 </span><span class="subxFunction">cursor-position</span>:  <span class="subxComment"># screen: (addr screen) -&gt; _/eax: int, _/ecx: int</span>
+<span id="L74" class="LineNr"> 74 </span>    <span class="subxS1Comment"># . prologue</span>
+<span id="L75" class="LineNr"> 75 </span>    55/push-ebp
+<span id="L76" class="LineNr"> 76 </span>    89/&lt;- %ebp 4/r32/esp
+<span id="L77" class="LineNr"> 77 </span>    <span class="subxComment"># TODO: support fake screen; we currently assume 'screen' is always 0 (real)</span>
+<span id="L78" class="LineNr"> 78 </span>    8b/-&gt; *<span class="SpecialChar"><a href='103grapheme.subx.html#L107'>Default-next-x</a></span> 0/r32/eax
+<span id="L79" class="LineNr"> 79 </span>    8b/-&gt; *<span class="SpecialChar"><a href='103grapheme.subx.html#L110'>Default-next-y</a></span> 1/r32/ecx
+<span id="L80" class="LineNr"> 80 </span><span class="Constant">$cursor-position:end</span>:
+<span id="L81" class="LineNr"> 81 </span>    <span class="subxS1Comment"># . epilogue</span>
+<span id="L82" class="LineNr"> 82 </span>    89/&lt;- %esp 5/r32/ebp
+<span id="L83" class="LineNr"> 83 </span>    5d/pop-to-ebp
+<span id="L84" class="LineNr"> 84 </span>    c3/return
+<span id="L85" class="LineNr"> 85 </span>
+<span id="L86" class="LineNr"> 86 </span><span class="subxFunction">set-cursor-position</span>:  <span class="subxComment"># screen: (addr screen), x: int, y: int</span>
+<span id="L87" class="LineNr"> 87 </span>    <span class="subxS1Comment"># . prologue</span>
+<span id="L88" class="LineNr"> 88 </span>    55/push-ebp
+<span id="L89" class="LineNr"> 89 </span>    89/&lt;- %ebp 4/r32/esp
+<span id="L90" class="LineNr"> 90 </span>    <span class="subxS1Comment"># . save registers</span>
+<span id="L91" class="LineNr"> 91 </span>    50/push-eax
+<span id="L92" class="LineNr"> 92 </span>    <span class="subxComment"># TODO: support fake screen; we currently assume 'screen' is always 0 (real)</span>
+<span id="L93" class="LineNr"> 93 </span>    8b/-&gt; *(ebp+0xc) 0/r32/eax
+<span id="L94" class="LineNr"> 94 </span>    89/&lt;- *<span class="SpecialChar"><a href='103grapheme.subx.html#L107'>Default-next-x</a></span> 0/r32/eax
+<span id="L95" class="LineNr"> 95 </span>    8b/-&gt; *(ebp+0x10) 0/r32/eax
+<span id="L96" class="LineNr"> 96 </span>    89/&lt;- *<span class="SpecialChar"><a href='103grapheme.subx.html#L110'>Default-next-y</a></span> 0/r32/eax
+<span id="L97" class="LineNr"> 97 </span><span class="Constant">$set-cursor-position:end</span>:
+<span id="L98" class="LineNr"> 98 </span>    <span class="subxS1Comment"># . restore registers</span>
+<span id="L99" class="LineNr"> 99 </span>    58/pop-to-eax
+<span id="L100" class="LineNr">100 </span>    <span class="subxS1Comment"># . epilogue</span>
+<span id="L101" class="LineNr">101 </span>    89/&lt;- %esp 5/r32/ebp
+<span id="L102" class="LineNr">102 </span>    5d/pop-to-ebp
+<span id="L103" class="LineNr">103 </span>    c3/return
+<span id="L104" class="LineNr">104 </span>
+<span id="L105" class="LineNr">105 </span>== data
+<span id="L106" class="LineNr">106 </span>
+<span id="L107" class="LineNr">107 </span><span class="SpecialChar">Default-next-x</span>:
+<span id="L108" class="LineNr">108 </span>  0/imm32
+<span id="L109" class="LineNr">109 </span>
+<span id="L110" class="LineNr">110 </span><span class="SpecialChar">Default-next-y</span>:
+<span id="L111" class="LineNr">111 </span>  0/imm32
 </pre>
 </body>
 </html>
diff --git a/html/baremetal/106stream.subx.html b/html/baremetal/106stream.subx.html
new file mode 100644
index 00000000..cbd859ea
--- /dev/null
+++ b/html/baremetal/106stream.subx.html
@@ -0,0 +1,137 @@
+<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN" "http://www.w3.org/TR/html4/strict.dtd">
+<html>
+<head>
+<meta http-equiv="content-type" content="text/html; charset=UTF-8">
+<title>Mu - baremetal/106stream.subx</title>
+<meta name="Generator" content="Vim/8.1">
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+<a href='https://github.com/akkartik/mu/blob/main/baremetal/106stream.subx'>https://github.com/akkartik/mu/blob/main/baremetal/106stream.subx</a>
+<pre id='vimCodeElement'>
+<span id="L1" class="LineNr"> 1 </span><span class="subxComment"># streams: data structure for operating on arrays in a stateful manner</span>
+<span id="L2" class="LineNr"> 2 </span><span class="subxComment">#</span>
+<span id="L3" class="LineNr"> 3 </span><span class="subxComment"># A stream looks like this:</span>
+<span id="L4" class="LineNr"> 4 </span><span class="subxComment">#   write: int  # index at which writes go</span>
+<span id="L5" class="LineNr"> 5 </span><span class="subxComment">#   read: int  # index that we've read until</span>
+<span id="L6" class="LineNr"> 6 </span><span class="subxComment">#   data: (array byte)  # prefixed by size as usual</span>
+<span id="L7" class="LineNr"> 7 </span><span class="subxComment">#</span>
+<span id="L8" class="LineNr"> 8 </span><span class="subxComment"># some primitives for operating on streams:</span>
+<span id="L9" class="LineNr"> 9 </span><span class="subxComment">#   - clear-stream (clears everything but the data size)</span>
+<span id="L10" class="LineNr">10 </span><span class="subxComment">#   - rewind-stream (resets read pointer)</span>
+<span id="L11" class="LineNr">11 </span>
+<span id="L12" class="LineNr">12 </span>== code
+<span id="L13" class="LineNr">13 </span><span class="subxComment">#   instruction                     effective address                                                   register    displacement    immediate</span>
+<span id="L14" class="LineNr">14 </span><span class="subxS1Comment"># . op          subop               mod             rm32          base        index         scale       r32</span>
+<span id="L15" class="LineNr">15 </span><span class="subxS1Comment"># . 1-3 bytes   3 bits              2 bits          3 bits        3 bits      3 bits        2 bits      2 bits      0/1/2/4 bytes   0/1/2/4 bytes</span>
+<span id="L16" class="LineNr">16 </span>
+<span id="L17" class="LineNr">17 </span><span class="subxFunction">clear-stream</span>:  <span class="subxComment"># f: (addr stream byte)</span>
+<span id="L18" class="LineNr">18 </span>    <span class="subxS1Comment"># . prologue</span>
+<span id="L19" class="LineNr">19 </span>    55/push-ebp
+<span id="L20" class="LineNr">20 </span>    89/copy                         3/mod/direct    5/rm32/ebp   <span class="Normal"> . </span>         <span class="Normal"> . </span>           <span class="Normal"> . </span>          4/r32/esp  <span class="Normal"> . </span>             <span class="Normal"> . </span>                <span class="subxComment"># copy esp to ebp</span>
+<span id="L21" class="LineNr">21 </span>    <span class="subxS1Comment"># . save registers</span>
+<span id="L22" class="LineNr">22 </span>    50/push-eax
+<span id="L23" class="LineNr">23 </span>    51/push-ecx
+<span id="L24" class="LineNr">24 </span>    <span class="subxComment"># eax = f</span>
+<span id="L25" class="LineNr">25 </span>    8b/copy                         1/mod/*+disp8   5/rm32/ebp   <span class="Normal"> . </span>         <span class="Normal"> . </span>                        0/r32/eax   8/disp8        <span class="Normal"> . </span>                <span class="subxComment"># copy *(ebp+8) to eax</span>
+<span id="L26" class="LineNr">26 </span>    <span class="subxComment"># var count/ecx: int = f-&gt;size</span>
+<span id="L27" class="LineNr">27 </span>    8b/copy                         1/mod/*+disp8   0/rm32/eax   <span class="Normal"> . </span>         <span class="Normal"> . </span>           <span class="Normal"> . </span>          1/r32/ecx   8/disp8        <span class="Normal"> . </span>                <span class="subxComment"># copy *(eax+8) to ecx</span>
+<span id="L28" class="LineNr">28 </span>    <span class="subxComment"># var max/ecx: (addr byte) = &amp;f-&gt;data[f-&gt;size]</span>
+<span id="L29" class="LineNr">29 </span>    8d/copy-address                 1/mod/*+disp8   4/rm32/sib    0/base/eax  1/index/ecx  <span class="Normal"> . </span>          1/r32/ecx   0xc/disp8      <span class="Normal"> . </span>                <span class="subxComment"># copy eax+ecx+12 to ecx</span>
+<span id="L30" class="LineNr">30 </span>    <span class="subxComment"># f-&gt;write = 0</span>
+<span id="L31" class="LineNr">31 </span>    c7          0/subop/copy        0/mod/direct    0/rm32/eax   <span class="Normal"> . </span>         <span class="Normal"> . </span>           <span class="Normal"> . </span>         <span class="Normal"> . </span>         <span class="Normal"> . </span>              0/imm32           <span class="subxComment"># copy to *eax</span>
+<span id="L32" class="LineNr">32 </span>    <span class="subxComment"># f-&gt;read = 0</span>
+<span id="L33" class="LineNr">33 </span>    c7          0/subop/copy        1/mod/*+disp8   0/rm32/eax   <span class="Normal"> . </span>         <span class="Normal"> . </span>           <span class="Normal"> . </span>         <span class="Normal"> . </span>          4/disp8         0/imm32           <span class="subxComment"># copy to *(eax+4)</span>
+<span id="L34" class="LineNr">34 </span>    <span class="subxH1Comment"># - clear all stream data</span>
+<span id="L35" class="LineNr">35 </span>    <span class="subxH1Comment"># - this isn't strictly necessary, and it can slow things down *a lot*, but better safe than sorry.</span>
+<span id="L36" class="LineNr">36 </span>    <span class="subxComment"># var curr/eax: (addr byte) = f-&gt;data</span>
+<span id="L37" class="LineNr">37 </span>    81          0/subop/add         3/mod/direct    0/rm32/eax   <span class="Normal"> . </span>         <span class="Normal"> . </span>           <span class="Normal"> . </span>         <span class="Normal"> . </span>         <span class="Normal"> . </span>              0xc/imm32         <span class="subxComment"># add to eax</span>
+<span id="L38" class="LineNr">38 </span><span class="Constant">$clear-stream:loop</span>:
+<span id="L39" class="LineNr">39 </span>    <span class="subxComment"># if (curr &gt;= max) break</span>
+<span id="L40" class="LineNr">40 </span>    39/compare                      3/mod/direct    0/rm32/eax   <span class="Normal"> . </span>         <span class="Normal"> . </span>           <span class="Normal"> . </span>          1/r32/ecx  <span class="Normal"> . </span>             <span class="Normal"> . </span>                <span class="subxComment"># compare eax with ecx</span>
+<span id="L41" class="LineNr">41 </span>    73/jump-if-addr&gt;=  $clear-stream:end/disp8
+<span id="L42" class="LineNr">42 </span>    <span class="subxComment"># *curr = 0</span>
+<span id="L43" class="LineNr">43 </span>    c6          0/subop/copy-byte   0/mod/direct    0/rm32/eax   <span class="Normal"> . </span>         <span class="Normal"> . </span>           <span class="Normal"> . </span>         <span class="Normal"> . </span>         <span class="Normal"> . </span>              0/imm8            <span class="subxComment"># copy byte to *eax</span>
+<span id="L44" class="LineNr">44 </span>    <span class="subxComment"># ++curr</span>
+<span id="L45" class="LineNr">45 </span>    40/increment-eax
+<span id="L46" class="LineNr">46 </span>    eb/jump  $clear-stream:<span class="Constant">loop</span>/disp8
+<span id="L47" class="LineNr">47 </span><span class="Constant">$clear-stream:end</span>:
+<span id="L48" class="LineNr">48 </span>    <span class="subxS1Comment"># . restore registers</span>
+<span id="L49" class="LineNr">49 </span>    59/pop-to-ecx
+<span id="L50" class="LineNr">50 </span>    58/pop-to-eax
+<span id="L51" class="LineNr">51 </span>    <span class="subxS1Comment"># . epilogue</span>
+<span id="L52" class="LineNr">52 </span>    89/copy                         3/mod/direct    4/rm32/esp   <span class="Normal"> . </span>         <span class="Normal"> . </span>           <span class="Normal"> . </span>          5/r32/ebp  <span class="Normal"> . </span>             <span class="Normal"> . </span>                <span class="subxComment"># copy ebp to esp</span>
+<span id="L53" class="LineNr">53 </span>    5d/pop-to-ebp
+<span id="L54" class="LineNr">54 </span>    c3/return
+<span id="L55" class="LineNr">55 </span>
+<span id="L56" class="LineNr">56 </span><span class="subxFunction">rewind-stream</span>:  <span class="subxComment"># f: (addr stream byte)</span>
+<span id="L57" class="LineNr">57 </span>    <span class="subxS1Comment"># . prologue</span>
+<span id="L58" class="LineNr">58 </span>    55/push-ebp
+<span id="L59" class="LineNr">59 </span>    89/copy                         3/mod/direct    5/rm32/ebp   <span class="Normal"> . </span>         <span class="Normal"> . </span>           <span class="Normal"> . </span>          4/r32/esp  <span class="Normal"> . </span>             <span class="Normal"> . </span>                <span class="subxComment"># copy esp to ebp</span>
+<span id="L60" class="LineNr">60 </span>    <span class="subxS1Comment"># . save registers</span>
+<span id="L61" class="LineNr">61 </span>    50/push-eax
+<span id="L62" class="LineNr">62 </span>    <span class="subxComment"># eax = f</span>
+<span id="L63" class="LineNr">63 </span>    8b/copy                         1/mod/*+disp8   5/rm32/ebp   <span class="Normal"> . </span>         <span class="Normal"> . </span>                        0/r32/eax   8/disp8        <span class="Normal"> . </span>                <span class="subxComment"># copy *(ebp+8) to eax</span>
+<span id="L64" class="LineNr">64 </span>    <span class="subxComment"># f-&gt;read = 0</span>
+<span id="L65" class="LineNr">65 </span>    c7          0/subop/copy        1/mod/*+disp8   0/rm32/eax   <span class="Normal"> . </span>         <span class="Normal"> . </span>           <span class="Normal"> . </span>         <span class="Normal"> . </span>          4/disp8         0/imm32           <span class="subxComment"># copy to *(eax+4)</span>
+<span id="L66" class="LineNr">66 </span><span class="Constant">$rewind-stream:end</span>:
+<span id="L67" class="LineNr">67 </span>    <span class="subxS1Comment"># . restore registers</span>
+<span id="L68" class="LineNr">68 </span>    58/pop-to-eax
+<span id="L69" class="LineNr">69 </span>    <span class="subxS1Comment"># . epilogue</span>
+<span id="L70" class="LineNr">70 </span>    89/copy                         3/mod/direct    4/rm32/esp   <span class="Normal"> . </span>         <span class="Normal"> . </span>           <span class="Normal"> . </span>          5/r32/ebp  <span class="Normal"> . </span>             <span class="Normal"> . </span>                <span class="subxComment"># copy ebp to esp</span>
+<span id="L71" class="LineNr">71 </span>    5d/pop-to-ebp
+<span id="L72" class="LineNr">72 </span>    c3/return
+<span id="L73" class="LineNr">73 </span>
+<span id="L74" class="LineNr">74 </span><span class="subxS2Comment"># . . vim&#0058;nowrap:textwidth=0</span>
+</pre>
+</body>
+</html>
+<!-- vim: set foldmethod=manual : -->
diff --git a/html/baremetal/108write.subx.html b/html/baremetal/108write.subx.html
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diff --git a/html/baremetal/112read-byte.subx.html b/html/baremetal/112read-byte.subx.html
index 9fb89fd0..06271ee0 100644
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+++ b/html/baremetal/112read-byte.subx.html
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-.Constant { color: #008787; }
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diff --git a/html/baremetal/115write-byte.subx.html b/html/baremetal/115write-byte.subx.html
index 43cbc843..7bcd8a8a 100644
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+++ b/html/baremetal/115write-byte.subx.html
@@ -18,9 +18,9 @@ a { color:inherit; }
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diff --git a/html/baremetal/120allocate.subx.html b/html/baremetal/120allocate.subx.html
index e11f9b00..11c874ee 100644
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+++ b/html/baremetal/120allocate.subx.html
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diff --git a/html/baremetal/302stack_allocate.subx.html b/html/baremetal/302stack_allocate.subx.html
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+++ b/html/baremetal/302stack_allocate.subx.html
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-.LineNr { }
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-.CommentedCode { color: #8a8a8a; }
+.LineNr { }
 .subxFunction { color: #af5f00; text-decoration: underline; }
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+.CommentedCode { color: #8a8a8a; }
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diff --git a/html/baremetal/309stream.subx.html b/html/baremetal/309stream.subx.html
index bbfd368b..16e45ed7 100644
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+++ b/html/baremetal/309stream.subx.html
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diff --git a/html/baremetal/313index-bounds-check.subx.html b/html/baremetal/313index-bounds-check.subx.html
index e364e785..a6421293 100644
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+++ b/html/baremetal/313index-bounds-check.subx.html
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diff --git a/html/baremetal/400.mu.html b/html/baremetal/400.mu.html
index 715c8d09..95835ad8 100644
--- a/html/baremetal/400.mu.html
+++ b/html/baremetal/400.mu.html
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 a { color:inherit; }
 * { font-size:12pt; font-size: 1em; }
+.PreProc { color: #c000c0; }
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-.PreProc { color: #c000c0; }
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@@ -52,14 +52,17 @@ if ('onhashchange' in window) {
 <body onload='JumpToLine();'>
 <a href='https://github.com/akkartik/mu/blob/main/baremetal/400.mu'>https://github.com/akkartik/mu/blob/main/baremetal/400.mu</a>
 <pre id='vimCodeElement'>
-<span id="L1" class="LineNr">1 </span><span class="PreProc">sig</span> <a href='101screen.subx.html#L3'>pixel</a> screen: (addr screen), x: int, y: int, color: int
-<span id="L2" class="LineNr">2 </span><span class="PreProc">sig</span> <a href='102keyboard.subx.html#L3'>read-key</a> kbd: (addr keyboard)<span class="PreProc"> -&gt; </span>_/<span class="Constant">eax</span>: byte
-<span id="L3" class="LineNr">3 </span><span class="PreProc">sig</span> <a href='103grapheme.subx.html#L1'>draw-grapheme</a> screen: (addr screen), g: grapheme, x: int, y: int, color: int
-<span id="L4" class="LineNr">4 </span>
-<span id="L5" class="LineNr">5 </span><span class="PreProc">sig</span> <a href='108write.subx.html#L5'>write</a> f: (addr stream byte), s: (addr array byte)
-<span id="L6" class="LineNr">6 </span><span class="PreProc">sig</span> <a href='115write-byte.subx.html#L6'>append-byte</a> f: (addr stream byte), n: int
-<span id="L7" class="LineNr">7 </span><span class="PreProc">sig</span> <a href='112read-byte.subx.html#L9'>read-byte</a> s: (addr stream byte)<span class="PreProc"> -&gt; </span>_/<span class="Constant">eax</span>: byte
-<span id="L8" class="LineNr">8 </span><span class="PreProc">sig</span> <a href='309stream.subx.html#L6'>stream-empty?</a> s: (addr stream _)<span class="PreProc"> -&gt; </span>_/<span class="Constant">eax</span>: boolean
+<span id="L1" class="LineNr"> 1 </span><span class="PreProc">sig</span> <a href='101screen.subx.html#L3'>pixel</a> screen: (addr screen), x: int, y: int, color: int
+<span id="L2" class="LineNr"> 2 </span><span class="PreProc">sig</span> <a href='102keyboard.subx.html#L3'>read-key</a> kbd: (addr keyboard)<span class="PreProc"> -&gt; </span>_/<span class="Constant">eax</span>: byte
+<span id="L3" class="LineNr"> 3 </span><span class="PreProc">sig</span> <a href='103grapheme.subx.html#L1'>draw-grapheme</a> screen: (addr screen), g: grapheme, x: int, y: int, color: int
+<span id="L4" class="LineNr"> 4 </span><span class="PreProc">sig</span> <a href='103grapheme.subx.html#L73'>cursor-position</a> screen: (addr screen)<span class="PreProc"> -&gt; </span>_/<span class="Constant">eax</span>: int, _/<span class="Constant">ecx</span>: int
+<span id="L5" class="LineNr"> 5 </span><span class="PreProc">sig</span> <a href='103grapheme.subx.html#L86'>set-cursor-position</a> screen: (addr screen), x: int, y: int
+<span id="L6" class="LineNr"> 6 </span><span class="PreProc">sig</span> <a href='106stream.subx.html#L17'>clear-stream</a> f: (addr stream _)
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+<span id="L9" class="LineNr"> 9 </span><span class="PreProc">sig</span> <a href='115write-byte.subx.html#L6'>append-byte</a> f: (addr stream byte), n: int
+<span id="L10" class="LineNr">10 </span><span class="PreProc">sig</span> <a href='112read-byte.subx.html#L9'>read-byte</a> s: (addr stream byte)<span class="PreProc"> -&gt; </span>_/<span class="Constant">eax</span>: byte
+<span id="L11" class="LineNr">11 </span><span class="PreProc">sig</span> <a href='309stream.subx.html#L6'>stream-empty?</a> s: (addr stream _)<span class="PreProc"> -&gt; </span>_/<span class="Constant">eax</span>: boolean
 </pre>
 </body>
 </html>
diff --git a/html/baremetal/403unicode.mu.html b/html/baremetal/403unicode.mu.html
index 8151f6d4..bff11ca4 100644
--- a/html/baremetal/403unicode.mu.html
+++ b/html/baremetal/403unicode.mu.html
@@ -14,13 +14,13 @@ pre { white-space: pre-wrap; font-family: monospace; color: #000000; background-
 body { font-size:12pt; font-family: monospace; color: #000000; background-color: #c6c6c6; }
 a { color:inherit; }
 * { font-size:12pt; font-size: 1em; }
-.muComment { color: #005faf; }
+.PreProc { color: #c000c0; }
 .LineNr { }
+.Delimiter { color: #c000c0; }
 .SpecialChar { color: #d70000; }
 .Constant { color: #008787; }
 .muFunction { color: #af5f00; text-decoration: underline; }
-.Delimiter { color: #c000c0; }
-.PreProc { color: #c000c0; }
+.muComment { color: #005faf; }
 -->
 </style>
 
@@ -77,7 +77,7 @@ if ('onhashchange' in window) {
 <span id="L19" class="LineNr"> 19 </span><span class="muComment">#</span>
 <span id="L20" class="LineNr"> 20 </span><span class="muComment"># The day we want to support combining characters, this function will need to</span>
 <span id="L21" class="LineNr"> 21 </span><span class="muComment"># take multiple code points. Or something.</span>
-<span id="L22" class="LineNr"> 22 </span><span class="PreProc">fn</span> <span class="muFunction"><a href='403unicode.mu.html#L22'>to-grapheme</a></span> in: code-point<span class="PreProc"> -&gt; </span>_/<span class="Constant">eax</span>: grapheme <span class="Delimiter">{</span>
+<span id="L22" class="LineNr"> 22 </span><span class="PreProc">fn</span> <span class="muFunction">to-grapheme</span> in: code-point<span class="PreProc"> -&gt; </span>_/<span class="Constant">eax</span>: grapheme <span class="Delimiter">{</span>
 <span id="L23" class="LineNr"> 23 </span>  <span class="PreProc">var</span> c/<span class="Constant">eax</span>: int <span class="SpecialChar">&lt;-</span> copy in
 <span id="L24" class="LineNr"> 24 </span>  <span class="PreProc">var</span> num-trailers/<span class="Constant">ecx</span>: int <span class="SpecialChar">&lt;-</span> copy <span class="Constant">0</span>
 <span id="L25" class="LineNr"> 25 </span>  <span class="PreProc">var</span> first/<span class="Constant">edx</span>: int <span class="SpecialChar">&lt;-</span> copy <span class="Constant">0</span>
@@ -147,7 +147,7 @@ if ('onhashchange' in window) {
 <span id="L89" class="LineNr"> 89 </span><span class="muComment"># TODO: bring in tests once we have check-ints-equal</span>
 <span id="L90" class="LineNr"> 90 </span>
 <span id="L91" class="LineNr"> 91 </span><span class="muComment"># read the next grapheme from a stream of bytes</span>
-<span id="L92" class="LineNr"> 92 </span><span class="PreProc">fn</span> <span class="muFunction"><a href='403unicode.mu.html#L92'>read-grapheme</a></span> in: (addr stream byte)<span class="PreProc"> -&gt; </span>_/<span class="Constant">eax</span>: grapheme <span class="Delimiter">{</span>
+<span id="L92" class="LineNr"> 92 </span><span class="PreProc">fn</span> <span class="muFunction">read-grapheme</span> in: (addr stream byte)<span class="PreProc"> -&gt; </span>_/<span class="Constant">eax</span>: grapheme <span class="Delimiter">{</span>
 <span id="L93" class="LineNr"> 93 </span>  <span class="muComment"># if at eof, return EOF</span>
 <span id="L94" class="LineNr"> 94 </span>  <span class="Delimiter">{</span>
 <span id="L95" class="LineNr"> 95 </span>    <span class="PreProc">var</span> eof?/<span class="Constant">eax</span>: boolean <span class="SpecialChar">&lt;-</span> <a href='309stream.subx.html#L6'>stream-empty?</a> in
@@ -203,7 +203,7 @@ if ('onhashchange' in window) {
 <span id="L145" class="LineNr">145 </span>    <span class="PreProc">break-if-&lt;=</span>
 <span id="L146" class="LineNr">146 </span>    <span class="PreProc">var</span> tmp/<span class="Constant">eax</span>: byte <span class="SpecialChar">&lt;-</span> <a href='112read-byte.subx.html#L9'>read-byte</a> in
 <span id="L147" class="LineNr">147 </span>    <span class="PreProc">var</span> tmp2/<span class="Constant">eax</span>: int <span class="SpecialChar">&lt;-</span> copy tmp
-<span id="L148" class="LineNr">148 </span>    tmp2 <span class="SpecialChar">&lt;-</span> <a href='403unicode.mu.html#L159'>shift-left-bytes</a> tmp2, num-byte-shifts
+<span id="L148" class="LineNr">148 </span>    tmp2 <span class="SpecialChar">&lt;-</span> shift-left-bytes tmp2, num-byte-shifts
 <span id="L149" class="LineNr">149 </span>    result <span class="SpecialChar">&lt;-</span> or tmp2
 <span id="L150" class="LineNr">150 </span>    <span class="muComment"># update loop state</span>
 <span id="L151" class="LineNr">151 </span>    num-byte-shifts <span class="SpecialChar">&lt;-</span> increment
@@ -214,7 +214,7 @@ if ('onhashchange' in window) {
 <span id="L156" class="LineNr">156 </span><span class="Delimiter">}</span>
 <span id="L157" class="LineNr">157 </span>
 <span id="L158" class="LineNr">158 </span><span class="muComment"># needed because available primitives only shift by a literal/constant number of bits</span>
-<span id="L159" class="LineNr">159 </span><span class="PreProc">fn</span> <span class="muFunction"><a href='403unicode.mu.html#L159'>shift-left-bytes</a></span> n: int, k: int<span class="PreProc"> -&gt; </span>_/<span class="Constant">eax</span>: int <span class="Delimiter">{</span>
+<span id="L159" class="LineNr">159 </span><span class="PreProc">fn</span> <span class="muFunction">shift-left-bytes</span> n: int, k: int<span class="PreProc"> -&gt; </span>_/<span class="Constant">eax</span>: int <span class="Delimiter">{</span>
 <span id="L160" class="LineNr">160 </span>  <span class="PreProc">var</span> i/<span class="Constant">ecx</span>: int <span class="SpecialChar">&lt;-</span> copy <span class="Constant">0</span>
 <span id="L161" class="LineNr">161 </span>  <span class="PreProc">var</span> result/<span class="Constant">eax</span>: int <span class="SpecialChar">&lt;-</span> copy n
 <span id="L162" class="LineNr">162 </span>  <span class="Delimiter">{</span>
@@ -231,7 +231,7 @@ if ('onhashchange' in window) {
 <span id="L173" class="LineNr">173 </span>
 <span id="L174" class="LineNr">174 </span><span class="muComment"># write a grapheme to a stream of bytes</span>
 <span id="L175" class="LineNr">175 </span><span class="muComment"># this is like write-to-stream, except we skip leading 0 bytes</span>
-<span id="L176" class="LineNr">176 </span><span class="PreProc">fn</span> <span class="muFunction"><a href='403unicode.mu.html#L176'>write-grapheme</a></span> out: (addr stream byte), g: grapheme <span class="Delimiter">{</span>
+<span id="L176" class="LineNr">176 </span><span class="PreProc">fn</span> <span class="muFunction">write-grapheme</span> out: (addr stream byte), g: grapheme <span class="Delimiter">{</span>
 <span id="L177" class="LineNr">177 </span>$write-grapheme:body: <span class="Delimiter">{</span>
 <span id="L178" class="LineNr">178 </span>  <span class="PreProc">var</span> c/<span class="Constant">eax</span>: int <span class="SpecialChar">&lt;-</span> copy g
 <span id="L179" class="LineNr">179 </span>  <a href='115write-byte.subx.html#L6'>append-byte</a> out, c  <span class="muComment"># first byte is always written</span>
diff --git a/html/baremetal/501draw-text.mu.html b/html/baremetal/501draw-text.mu.html
index 61ece7dc..fd1c6df8 100644
--- a/html/baremetal/501draw-text.mu.html
+++ b/html/baremetal/501draw-text.mu.html
@@ -14,13 +14,13 @@ pre { white-space: pre-wrap; font-family: monospace; color: #000000; background-
 body { font-size:12pt; font-family: monospace; color: #000000; background-color: #c6c6c6; }
 a { color:inherit; }
 * { font-size:12pt; font-size: 1em; }
-.muComment { color: #005faf; }
+.PreProc { color: #c000c0; }
 .LineNr { }
-.SpecialChar { color: #d70000; }
 .Delimiter { color: #c000c0; }
-.muFunction { color: #af5f00; text-decoration: underline; }
+.SpecialChar { color: #d70000; }
 .Constant { color: #008787; }
-.PreProc { color: #c000c0; }
+.muFunction { color: #af5f00; text-decoration: underline; }
+.muComment { color: #005faf; }
 -->
 </style>
 
@@ -56,19 +56,265 @@ if ('onhashchange' in window) {
 <body onload='JumpToLine();'>
 <a href='https://github.com/akkartik/mu/blob/main/baremetal/501draw-text.mu'>https://github.com/akkartik/mu/blob/main/baremetal/501draw-text.mu</a>
 <pre id='vimCodeElement'>
-<span id="L1" class="LineNr"> 1 </span><span class="PreProc">fn</span> <span class="muFunction"><a href='501draw-text.mu.html#L1'>draw-text-rightward</a></span> screen: (addr screen), text: (addr array byte), x: int, y: int, color: int <span class="Delimiter">{</span>
-<span id="L2" class="LineNr"> 2 </span>  <span class="PreProc">var</span> stream-storage: (stream byte <span class="Constant">0x100</span>)
-<span id="L3" class="LineNr"> 3 </span>  <span class="PreProc">var</span> stream/<span class="Constant">esi</span>: (addr stream byte) <span class="SpecialChar">&lt;-</span> address stream-storage
-<span id="L4" class="LineNr"> 4 </span>  <a href='108write.subx.html#L5'>write</a> stream, text
-<span id="L5" class="LineNr"> 5 </span>  <span class="Delimiter">{</span>
-<span id="L6" class="LineNr"> 6 </span>    <span class="PreProc">var</span> g/<span class="Constant">eax</span>: grapheme <span class="SpecialChar">&lt;-</span> <a href='403unicode.mu.html#L92'>read-grapheme</a> stream
-<span id="L7" class="LineNr"> 7 </span>    compare g, <span class="Constant">0xffffffff</span>  <span class="muComment"># end-of-file</span>
-<span id="L8" class="LineNr"> 8 </span>    <span class="PreProc">break-if-=</span>
-<span id="L9" class="LineNr"> 9 </span>    <a href='103grapheme.subx.html#L1'>draw-grapheme</a> screen, g, x, y, color
-<span id="L10" class="LineNr">10 </span>    add-to x, <span class="Constant">8</span>  <span class="muComment"># font-width</span>
-<span id="L11" class="LineNr">11 </span>    <span class="PreProc">loop</span>
-<span id="L12" class="LineNr">12 </span>  <span class="Delimiter">}</span>
-<span id="L13" class="LineNr">13 </span><span class="Delimiter">}</span>
+<span id="L1" class="LineNr">  1 </span><span class="muComment"># draw a single line of text from x, y to xmax</span>
+<span id="L2" class="LineNr">  2 </span><span class="muComment"># return the next 'x' coordinate</span>
+<span id="L3" class="LineNr">  3 </span><span class="muComment"># if there isn't enough space, return 0 without modifying the screen</span>
+<span id="L4" class="LineNr">  4 </span><span class="PreProc">fn</span> <span class="muFunction">draw-text-rightward</span> screen: (addr screen), text: (addr array byte), x: int, xmax: int, y: int, color: int<span class="PreProc"> -&gt; </span>_/<span class="Constant">eax</span>: int <span class="Delimiter">{</span>
+<span id="L5" class="LineNr">  5 </span>  <span class="PreProc">var</span> stream-storage: (stream byte <span class="Constant">0x100</span>)
+<span id="L6" class="LineNr">  6 </span>  <span class="PreProc">var</span> stream/<span class="Constant">esi</span>: (addr stream byte) <span class="SpecialChar">&lt;-</span> address stream-storage
+<span id="L7" class="LineNr">  7 </span>  <a href='108write.subx.html#L5'>write</a> stream, text
+<span id="L8" class="LineNr">  8 </span>  <span class="muComment"># check if we have enough space</span>
+<span id="L9" class="LineNr">  9 </span>  <span class="PreProc">var</span> xcurr/<span class="Constant">ecx</span>: int <span class="SpecialChar">&lt;-</span> copy x
+<span id="L10" class="LineNr"> 10 </span>  <span class="Delimiter">{</span>
+<span id="L11" class="LineNr"> 11 </span>    compare xcurr, xmax
+<span id="L12" class="LineNr"> 12 </span>    <span class="PreProc">break-if-&gt;</span>
+<span id="L13" class="LineNr"> 13 </span>    <span class="PreProc">var</span> g/<span class="Constant">eax</span>: grapheme <span class="SpecialChar">&lt;-</span> read-grapheme stream
+<span id="L14" class="LineNr"> 14 </span>    compare g, <span class="Constant">0xffffffff</span>  <span class="muComment"># end-of-file</span>
+<span id="L15" class="LineNr"> 15 </span>    <span class="PreProc">break-if-=</span>
+<span id="L16" class="LineNr"> 16 </span>    xcurr <span class="SpecialChar">&lt;-</span> add <span class="Constant">8</span>  <span class="muComment"># font-width</span>
+<span id="L17" class="LineNr"> 17 </span>    <span class="PreProc">loop</span>
+<span id="L18" class="LineNr"> 18 </span>  <span class="Delimiter">}</span>
+<span id="L19" class="LineNr"> 19 </span>  compare xcurr, xmax
+<span id="L20" class="LineNr"> 20 </span>  <span class="Delimiter">{</span>
+<span id="L21" class="LineNr"> 21 </span>    <span class="PreProc">break-if-&lt;=</span>
+<span id="L22" class="LineNr"> 22 </span>    <span class="PreProc">return</span> <span class="Constant">0</span>
+<span id="L23" class="LineNr"> 23 </span>  <span class="Delimiter">}</span>
+<span id="L24" class="LineNr"> 24 </span>  <span class="muComment"># we do; actually draw</span>
+<span id="L25" class="LineNr"> 25 </span>  <a href='106stream.subx.html#L56'>rewind-stream</a> stream
+<span id="L26" class="LineNr"> 26 </span>  xcurr <span class="SpecialChar">&lt;-</span> copy x
+<span id="L27" class="LineNr"> 27 </span>  <span class="Delimiter">{</span>
+<span id="L28" class="LineNr"> 28 </span>    <span class="PreProc">var</span> g/<span class="Constant">eax</span>: grapheme <span class="SpecialChar">&lt;-</span> read-grapheme stream
+<span id="L29" class="LineNr"> 29 </span>    compare g, <span class="Constant">0xffffffff</span>  <span class="muComment"># end-of-file</span>
+<span id="L30" class="LineNr"> 30 </span>    <span class="PreProc">break-if-=</span>
+<span id="L31" class="LineNr"> 31 </span>    <a href='103grapheme.subx.html#L1'>draw-grapheme</a> screen, g, xcurr, y, color
+<span id="L32" class="LineNr"> 32 </span>    xcurr <span class="SpecialChar">&lt;-</span> add <span class="Constant">8</span>  <span class="muComment"># font-width</span>
+<span id="L33" class="LineNr"> 33 </span>    <span class="PreProc">loop</span>
+<span id="L34" class="LineNr"> 34 </span>  <span class="Delimiter">}</span>
+<span id="L35" class="LineNr"> 35 </span>  <a href='103grapheme.subx.html#L86'>set-cursor-position</a> screen, xcurr, y
+<span id="L36" class="LineNr"> 36 </span>  <span class="PreProc">return</span> xcurr
+<span id="L37" class="LineNr"> 37 </span><span class="Delimiter">}</span>
+<span id="L38" class="LineNr"> 38 </span>
+<span id="L39" class="LineNr"> 39 </span><span class="PreProc">fn</span> <span class="muFunction">draw-text-rightward-from-cursor</span> screen: (addr screen), text: (addr array byte), xmax: int, color: int<span class="PreProc"> -&gt; </span>_/<span class="Constant">eax</span>: int <span class="Delimiter">{</span>
+<span id="L40" class="LineNr"> 40 </span>  <span class="PreProc">var</span> cursor-x/<span class="Constant">eax</span>: int <span class="SpecialChar">&lt;-</span> copy <span class="Constant">0</span>
+<span id="L41" class="LineNr"> 41 </span>  <span class="PreProc">var</span> cursor-y/<span class="Constant">ecx</span>: int <span class="SpecialChar">&lt;-</span> copy <span class="Constant">0</span>
+<span id="L42" class="LineNr"> 42 </span>  cursor-x, cursor-y <span class="SpecialChar">&lt;-</span> <a href='103grapheme.subx.html#L73'>cursor-position</a> screen
+<span id="L43" class="LineNr"> 43 </span>  <span class="PreProc">var</span> result/<span class="Constant">eax</span>: int <span class="SpecialChar">&lt;-</span> draw-text-rightward screen, text, cursor-x, xmax, cursor-y, color
+<span id="L44" class="LineNr"> 44 </span>  <span class="PreProc">return</span> result
+<span id="L45" class="LineNr"> 45 </span><span class="Delimiter">}</span>
+<span id="L46" class="LineNr"> 46 </span>
+<span id="L47" class="LineNr"> 47 </span><span class="muComment"># draw text in the rectangle from (xmin, ymin) to (xmax, ymax), starting from (x, y), wrapping as necessary</span>
+<span id="L48" class="LineNr"> 48 </span><span class="muComment"># return the next (x, y) coordinate in raster order where drawing stopped</span>
+<span id="L49" class="LineNr"> 49 </span><span class="muComment"># that way the caller can draw more if given the same min and max bounding-box.</span>
+<span id="L50" class="LineNr"> 50 </span><span class="muComment"># if there isn't enough space, return 0 without modifying the screen</span>
+<span id="L51" class="LineNr"> 51 </span><span class="PreProc">fn</span> <span class="muFunction">draw-text-wrapping-right-then-down</span> screen: (addr screen), text: (addr array byte), xmin: int, ymin: int, xmax: int, ymax: int, x: int, y: int, color: int<span class="PreProc"> -&gt; </span>_/<span class="Constant">eax</span>: int, _/<span class="Constant">ecx</span>: int <span class="Delimiter">{</span>
+<span id="L52" class="LineNr"> 52 </span>  <span class="PreProc">var</span> stream-storage: (stream byte <span class="Constant">0x100</span>)
+<span id="L53" class="LineNr"> 53 </span>  <span class="PreProc">var</span> stream/<span class="Constant">esi</span>: (addr stream byte) <span class="SpecialChar">&lt;-</span> address stream-storage
+<span id="L54" class="LineNr"> 54 </span>  <a href='108write.subx.html#L5'>write</a> stream, text
+<span id="L55" class="LineNr"> 55 </span>  <span class="muComment"># check if we have enough space</span>
+<span id="L56" class="LineNr"> 56 </span>  <span class="PreProc">var</span> xcurr/<span class="Constant">edx</span>: int <span class="SpecialChar">&lt;-</span> copy x
+<span id="L57" class="LineNr"> 57 </span>  <span class="PreProc">var</span> ycurr/<span class="Constant">ecx</span>: int <span class="SpecialChar">&lt;-</span> copy y
+<span id="L58" class="LineNr"> 58 </span>  <span class="Delimiter">{</span>
+<span id="L59" class="LineNr"> 59 </span>    compare ycurr, ymax
+<span id="L60" class="LineNr"> 60 </span>    <span class="PreProc">break-if-&gt;=</span>
+<span id="L61" class="LineNr"> 61 </span>    <span class="PreProc">var</span> g/<span class="Constant">eax</span>: grapheme <span class="SpecialChar">&lt;-</span> read-grapheme stream
+<span id="L62" class="LineNr"> 62 </span>    compare g, <span class="Constant">0xffffffff</span>  <span class="muComment"># end-of-file</span>
+<span id="L63" class="LineNr"> 63 </span>    <span class="PreProc">break-if-=</span>
+<span id="L64" class="LineNr"> 64 </span>    xcurr <span class="SpecialChar">&lt;-</span> add <span class="Constant">8</span>  <span class="muComment"># font-width</span>
+<span id="L65" class="LineNr"> 65 </span>    compare xcurr, xmax
+<span id="L66" class="LineNr"> 66 </span>    <span class="Delimiter">{</span>
+<span id="L67" class="LineNr"> 67 </span>      <span class="PreProc">break-if-&lt;</span>
+<span id="L68" class="LineNr"> 68 </span>      xcurr <span class="SpecialChar">&lt;-</span> copy xmin
+<span id="L69" class="LineNr"> 69 </span>      ycurr <span class="SpecialChar">&lt;-</span> add <span class="Constant">0x10</span>  <span class="muComment"># font-height</span>
+<span id="L70" class="LineNr"> 70 </span>    <span class="Delimiter">}</span>
+<span id="L71" class="LineNr"> 71 </span>    <span class="PreProc">loop</span>
+<span id="L72" class="LineNr"> 72 </span>  <span class="Delimiter">}</span>
+<span id="L73" class="LineNr"> 73 </span>  compare ycurr, ymax
+<span id="L74" class="LineNr"> 74 </span>  <span class="Delimiter">{</span>
+<span id="L75" class="LineNr"> 75 </span>    <span class="PreProc">break-if-&lt;</span>
+<span id="L76" class="LineNr"> 76 </span>    <span class="PreProc">return</span> <span class="Constant">0</span>, <span class="Constant">0</span>
+<span id="L77" class="LineNr"> 77 </span>  <span class="Delimiter">}</span>
+<span id="L78" class="LineNr"> 78 </span>  <span class="muComment"># we do; actually draw</span>
+<span id="L79" class="LineNr"> 79 </span>  <a href='106stream.subx.html#L56'>rewind-stream</a> stream
+<span id="L80" class="LineNr"> 80 </span>  xcurr <span class="SpecialChar">&lt;-</span> copy x
+<span id="L81" class="LineNr"> 81 </span>  ycurr <span class="SpecialChar">&lt;-</span> copy y
+<span id="L82" class="LineNr"> 82 </span>  <span class="Delimiter">{</span>
+<span id="L83" class="LineNr"> 83 </span>    <span class="PreProc">var</span> g/<span class="Constant">eax</span>: grapheme <span class="SpecialChar">&lt;-</span> read-grapheme stream
+<span id="L84" class="LineNr"> 84 </span>    compare g, <span class="Constant">0xffffffff</span>  <span class="muComment"># end-of-file</span>
+<span id="L85" class="LineNr"> 85 </span>    <span class="PreProc">break-if-=</span>
+<span id="L86" class="LineNr"> 86 </span>    <a href='103grapheme.subx.html#L1'>draw-grapheme</a> screen, g, xcurr, ycurr, color
+<span id="L87" class="LineNr"> 87 </span>    xcurr <span class="SpecialChar">&lt;-</span> add <span class="Constant">8</span>  <span class="muComment"># font-width</span>
+<span id="L88" class="LineNr"> 88 </span>    compare xcurr, xmax
+<span id="L89" class="LineNr"> 89 </span>    <span class="Delimiter">{</span>
+<span id="L90" class="LineNr"> 90 </span>      <span class="PreProc">break-if-&lt;</span>
+<span id="L91" class="LineNr"> 91 </span>      xcurr <span class="SpecialChar">&lt;-</span> copy xmin
+<span id="L92" class="LineNr"> 92 </span>      ycurr <span class="SpecialChar">&lt;-</span> add <span class="Constant">0x10</span>  <span class="muComment"># font-height</span>
+<span id="L93" class="LineNr"> 93 </span>    <span class="Delimiter">}</span>
+<span id="L94" class="LineNr"> 94 </span>    <span class="PreProc">loop</span>
+<span id="L95" class="LineNr"> 95 </span>  <span class="Delimiter">}</span>
+<span id="L96" class="LineNr"> 96 </span>  <a href='103grapheme.subx.html#L86'>set-cursor-position</a> screen, xcurr, ycurr
+<span id="L97" class="LineNr"> 97 </span>  <span class="PreProc">return</span> xcurr, ycurr
+<span id="L98" class="LineNr"> 98 </span><span class="Delimiter">}</span>
+<span id="L99" class="LineNr"> 99 </span>
+<span id="L100" class="LineNr">100 </span><span class="PreProc">fn</span> <span class="muFunction">draw-text-wrapping-right-then-down-over-full-screen</span> screen: (addr screen), text: (addr array byte), x: int, y: int, color: int<span class="PreProc"> -&gt; </span>_/<span class="Constant">eax</span>: int, _/<span class="Constant">ecx</span>: int <span class="Delimiter">{</span>
+<span id="L101" class="LineNr">101 </span>  <span class="PreProc">var</span> cursor-x/<span class="Constant">eax</span>: int <span class="SpecialChar">&lt;-</span> copy <span class="Constant">0</span>
+<span id="L102" class="LineNr">102 </span>  <span class="PreProc">var</span> cursor-y/<span class="Constant">ecx</span>: int <span class="SpecialChar">&lt;-</span> copy <span class="Constant">0</span>
+<span id="L103" class="LineNr">103 </span>  cursor-x, cursor-y <span class="SpecialChar">&lt;-</span> draw-text-wrapping-right-then-down screen, text, <span class="Constant">0</span>, <span class="Constant">0</span>, <span class="Constant">0x400</span>, <span class="Constant">0x300</span>, x, y, color  <span class="muComment"># 1024, 768</span>
+<span id="L104" class="LineNr">104 </span>  <span class="PreProc">return</span> cursor-x, cursor-y
+<span id="L105" class="LineNr">105 </span><span class="Delimiter">}</span>
+<span id="L106" class="LineNr">106 </span>
+<span id="L107" class="LineNr">107 </span><span class="PreProc">fn</span> <span class="muFunction">draw-text-wrapping-right-then-down-from-cursor</span> screen: (addr screen), text: (addr array byte), xmin: int, ymin: int, xmax: int, ymax: int, color: int<span class="PreProc"> -&gt; </span>_/<span class="Constant">eax</span>: int, _/<span class="Constant">ecx</span>: int <span class="Delimiter">{</span>
+<span id="L108" class="LineNr">108 </span>  <span class="PreProc">var</span> cursor-x/<span class="Constant">eax</span>: int <span class="SpecialChar">&lt;-</span> copy <span class="Constant">0</span>
+<span id="L109" class="LineNr">109 </span>  <span class="PreProc">var</span> cursor-y/<span class="Constant">ecx</span>: int <span class="SpecialChar">&lt;-</span> copy <span class="Constant">0</span>
+<span id="L110" class="LineNr">110 </span>  cursor-x, cursor-y <span class="SpecialChar">&lt;-</span> <a href='103grapheme.subx.html#L73'>cursor-position</a> screen
+<span id="L111" class="LineNr">111 </span>  <span class="PreProc">var</span> end-x/<span class="Constant">edx</span>: int <span class="SpecialChar">&lt;-</span> copy cursor-x
+<span id="L112" class="LineNr">112 </span>  end-x <span class="SpecialChar">&lt;-</span> add <span class="Constant">8</span>  <span class="muComment"># font-width</span>
+<span id="L113" class="LineNr">113 </span>  compare end-x, xmax
+<span id="L114" class="LineNr">114 </span>  <span class="Delimiter">{</span>
+<span id="L115" class="LineNr">115 </span>    <span class="PreProc">break-if-&lt;</span>
+<span id="L116" class="LineNr">116 </span>    cursor-x <span class="SpecialChar">&lt;-</span> copy xmin
+<span id="L117" class="LineNr">117 </span>    cursor-y <span class="SpecialChar">&lt;-</span> add <span class="Constant">0x10</span>  <span class="muComment"># font-height</span>
+<span id="L118" class="LineNr">118 </span>  <span class="Delimiter">}</span>
+<span id="L119" class="LineNr">119 </span>  cursor-x, cursor-y <span class="SpecialChar">&lt;-</span> draw-text-wrapping-right-then-down screen, text, xmin, ymin, xmax, ymax, cursor-x, cursor-y, color
+<span id="L120" class="LineNr">120 </span>  <span class="PreProc">return</span> cursor-x, cursor-y
+<span id="L121" class="LineNr">121 </span><span class="Delimiter">}</span>
+<span id="L122" class="LineNr">122 </span>
+<span id="L123" class="LineNr">123 </span><span class="PreProc">fn</span> <span class="muFunction">draw-text-wrapping-right-then-down-from-cursor-over-full-screen</span> screen: (addr screen), text: (addr array byte), color: int<span class="PreProc"> -&gt; </span>_/<span class="Constant">eax</span>: int, _/<span class="Constant">ecx</span>: int <span class="Delimiter">{</span>
+<span id="L124" class="LineNr">124 </span>  <span class="PreProc">var</span> cursor-x/<span class="Constant">eax</span>: int <span class="SpecialChar">&lt;-</span> copy <span class="Constant">0</span>
+<span id="L125" class="LineNr">125 </span>  <span class="PreProc">var</span> cursor-y/<span class="Constant">ecx</span>: int <span class="SpecialChar">&lt;-</span> copy <span class="Constant">0</span>
+<span id="L126" class="LineNr">126 </span>  cursor-x, cursor-y <span class="SpecialChar">&lt;-</span> draw-text-wrapping-right-then-down-from-cursor screen, text, <span class="Constant">0</span>, <span class="Constant">0</span>, <span class="Constant">0x400</span>, <span class="Constant">0x300</span>, color  <span class="muComment"># 1024, 768</span>
+<span id="L127" class="LineNr">127 </span>  <span class="PreProc">return</span> cursor-x, cursor-y
+<span id="L128" class="LineNr">128 </span><span class="Delimiter">}</span>
+<span id="L129" class="LineNr">129 </span>
+<span id="L130" class="LineNr">130 </span><span class="muComment">## Text direction: down then right</span>
+<span id="L131" class="LineNr">131 </span>
+<span id="L132" class="LineNr">132 </span><span class="muComment"># draw a single line of text vertically from x, y to ymax</span>
+<span id="L133" class="LineNr">133 </span><span class="muComment"># return the next 'y' coordinate</span>
+<span id="L134" class="LineNr">134 </span><span class="muComment"># if there isn't enough space, return 0 without modifying the screen</span>
+<span id="L135" class="LineNr">135 </span><span class="PreProc">fn</span> <span class="muFunction">draw-text-downward</span> screen: (addr screen), text: (addr array byte), x: int, y: int, ymax: int, color: int<span class="PreProc"> -&gt; </span>_/<span class="Constant">eax</span>: int <span class="Delimiter">{</span>
+<span id="L136" class="LineNr">136 </span>  <span class="PreProc">var</span> stream-storage: (stream byte <span class="Constant">0x100</span>)
+<span id="L137" class="LineNr">137 </span>  <span class="PreProc">var</span> stream/<span class="Constant">esi</span>: (addr stream byte) <span class="SpecialChar">&lt;-</span> address stream-storage
+<span id="L138" class="LineNr">138 </span>  <a href='108write.subx.html#L5'>write</a> stream, text
+<span id="L139" class="LineNr">139 </span>  <span class="muComment"># check if we have enough space</span>
+<span id="L140" class="LineNr">140 </span>  <span class="PreProc">var</span> ycurr/<span class="Constant">ecx</span>: int <span class="SpecialChar">&lt;-</span> copy y
+<span id="L141" class="LineNr">141 </span>  <span class="Delimiter">{</span>
+<span id="L142" class="LineNr">142 </span>    compare ycurr, ymax
+<span id="L143" class="LineNr">143 </span>    <span class="PreProc">break-if-&gt;</span>
+<span id="L144" class="LineNr">144 </span>    <span class="PreProc">var</span> g/<span class="Constant">eax</span>: grapheme <span class="SpecialChar">&lt;-</span> read-grapheme stream
+<span id="L145" class="LineNr">145 </span>    compare g, <span class="Constant">0xffffffff</span>  <span class="muComment"># end-of-file</span>
+<span id="L146" class="LineNr">146 </span>    <span class="PreProc">break-if-=</span>
+<span id="L147" class="LineNr">147 </span>    ycurr <span class="SpecialChar">&lt;-</span> add <span class="Constant">0x10</span>  <span class="muComment"># font-height</span>
+<span id="L148" class="LineNr">148 </span>    <span class="PreProc">loop</span>
+<span id="L149" class="LineNr">149 </span>  <span class="Delimiter">}</span>
+<span id="L150" class="LineNr">150 </span>  compare ycurr, ymax
+<span id="L151" class="LineNr">151 </span>  <span class="Delimiter">{</span>
+<span id="L152" class="LineNr">152 </span>    <span class="PreProc">break-if-&lt;=</span>
+<span id="L153" class="LineNr">153 </span>    <span class="PreProc">return</span> <span class="Constant">0</span>
+<span id="L154" class="LineNr">154 </span>  <span class="Delimiter">}</span>
+<span id="L155" class="LineNr">155 </span>  <span class="muComment"># we do; actually draw</span>
+<span id="L156" class="LineNr">156 </span>  <a href='106stream.subx.html#L56'>rewind-stream</a> stream
+<span id="L157" class="LineNr">157 </span>  ycurr <span class="SpecialChar">&lt;-</span> copy y
+<span id="L158" class="LineNr">158 </span>  <span class="Delimiter">{</span>
+<span id="L159" class="LineNr">159 </span>    <span class="PreProc">var</span> g/<span class="Constant">eax</span>: grapheme <span class="SpecialChar">&lt;-</span> read-grapheme stream
+<span id="L160" class="LineNr">160 </span>    compare g, <span class="Constant">0xffffffff</span>  <span class="muComment"># end-of-file</span>
+<span id="L161" class="LineNr">161 </span>    <span class="PreProc">break-if-=</span>
+<span id="L162" class="LineNr">162 </span>    <a href='103grapheme.subx.html#L1'>draw-grapheme</a> screen, g, x, ycurr, color
+<span id="L163" class="LineNr">163 </span>    ycurr <span class="SpecialChar">&lt;-</span> add <span class="Constant">0x10</span>  <span class="muComment"># font-height</span>
+<span id="L164" class="LineNr">164 </span>    <span class="PreProc">loop</span>
+<span id="L165" class="LineNr">165 </span>  <span class="Delimiter">}</span>
+<span id="L166" class="LineNr">166 </span>  <a href='103grapheme.subx.html#L86'>set-cursor-position</a> screen, x, ycurr
+<span id="L167" class="LineNr">167 </span>  <span class="PreProc">return</span> ycurr
+<span id="L168" class="LineNr">168 </span><span class="Delimiter">}</span>
+<span id="L169" class="LineNr">169 </span>
+<span id="L170" class="LineNr">170 </span><span class="PreProc">fn</span> <span class="muFunction">draw-text-downward-from-cursor</span> screen: (addr screen), text: (addr array byte), ymax: int, color: int<span class="PreProc"> -&gt; </span>_/<span class="Constant">eax</span>: int <span class="Delimiter">{</span>
+<span id="L171" class="LineNr">171 </span>  <span class="PreProc">var</span> cursor-x/<span class="Constant">eax</span>: int <span class="SpecialChar">&lt;-</span> copy <span class="Constant">0</span>
+<span id="L172" class="LineNr">172 </span>  <span class="PreProc">var</span> cursor-y/<span class="Constant">ecx</span>: int <span class="SpecialChar">&lt;-</span> copy <span class="Constant">0</span>
+<span id="L173" class="LineNr">173 </span>  cursor-x, cursor-y <span class="SpecialChar">&lt;-</span> <a href='103grapheme.subx.html#L73'>cursor-position</a> screen
+<span id="L174" class="LineNr">174 </span>  <span class="PreProc">var</span> result/<span class="Constant">eax</span>: int <span class="SpecialChar">&lt;-</span> draw-text-downward screen, text, cursor-x, cursor-y, ymax, color
+<span id="L175" class="LineNr">175 </span>  <span class="PreProc">return</span> result
+<span id="L176" class="LineNr">176 </span><span class="Delimiter">}</span>
+<span id="L177" class="LineNr">177 </span>
+<span id="L178" class="LineNr">178 </span><span class="muComment"># draw text down and right in the rectangle from (xmin, ymin) to (xmax, ymax), starting from (x, y), wrapping as necessary</span>
+<span id="L179" class="LineNr">179 </span><span class="muComment"># return the next (x, y) coordinate in raster order where drawing stopped</span>
+<span id="L180" class="LineNr">180 </span><span class="muComment"># that way the caller can draw more if given the same min and max bounding-box.</span>
+<span id="L181" class="LineNr">181 </span><span class="muComment"># if there isn't enough space, return 0 without modifying the screen</span>
+<span id="L182" class="LineNr">182 </span><span class="PreProc">fn</span> <span class="muFunction">draw-text-wrapping-down-then-right</span> screen: (addr screen), text: (addr array byte), xmin: int, ymin: int, xmax: int, ymax: int, x: int, y: int, color: int<span class="PreProc"> -&gt; </span>_/<span class="Constant">eax</span>: int, _/<span class="Constant">ecx</span>: int <span class="Delimiter">{</span>
+<span id="L183" class="LineNr">183 </span>  <span class="PreProc">var</span> stream-storage: (stream byte <span class="Constant">0x100</span>)
+<span id="L184" class="LineNr">184 </span>  <span class="PreProc">var</span> stream/<span class="Constant">esi</span>: (addr stream byte) <span class="SpecialChar">&lt;-</span> address stream-storage
+<span id="L185" class="LineNr">185 </span>  <a href='108write.subx.html#L5'>write</a> stream, text
+<span id="L186" class="LineNr">186 </span>  <span class="muComment"># check if we have enough space</span>
+<span id="L187" class="LineNr">187 </span>  <span class="PreProc">var</span> xcurr/<span class="Constant">edx</span>: int <span class="SpecialChar">&lt;-</span> copy x
+<span id="L188" class="LineNr">188 </span>  <span class="PreProc">var</span> ycurr/<span class="Constant">ecx</span>: int <span class="SpecialChar">&lt;-</span> copy y
+<span id="L189" class="LineNr">189 </span>  <span class="Delimiter">{</span>
+<span id="L190" class="LineNr">190 </span>    compare xcurr, xmax
+<span id="L191" class="LineNr">191 </span>    <span class="PreProc">break-if-&gt;=</span>
+<span id="L192" class="LineNr">192 </span>    <span class="PreProc">var</span> g/<span class="Constant">eax</span>: grapheme <span class="SpecialChar">&lt;-</span> read-grapheme stream
+<span id="L193" class="LineNr">193 </span>    compare g, <span class="Constant">0xffffffff</span>  <span class="muComment"># end-of-file</span>
+<span id="L194" class="LineNr">194 </span>    <span class="PreProc">break-if-=</span>
+<span id="L195" class="LineNr">195 </span>    ycurr <span class="SpecialChar">&lt;-</span> add <span class="Constant">0x10</span>  <span class="muComment"># font-height</span>
+<span id="L196" class="LineNr">196 </span>    compare ycurr, ymax
+<span id="L197" class="LineNr">197 </span>    <span class="Delimiter">{</span>
+<span id="L198" class="LineNr">198 </span>      <span class="PreProc">break-if-&lt;</span>
+<span id="L199" class="LineNr">199 </span>      xcurr <span class="SpecialChar">&lt;-</span> add <span class="Constant">8</span>  <span class="muComment"># font-width</span>
+<span id="L200" class="LineNr">200 </span>      ycurr <span class="SpecialChar">&lt;-</span> copy ymin
+<span id="L201" class="LineNr">201 </span>    <span class="Delimiter">}</span>
+<span id="L202" class="LineNr">202 </span>    <span class="PreProc">loop</span>
+<span id="L203" class="LineNr">203 </span>  <span class="Delimiter">}</span>
+<span id="L204" class="LineNr">204 </span>  compare xcurr, xmax
+<span id="L205" class="LineNr">205 </span>  <span class="Delimiter">{</span>
+<span id="L206" class="LineNr">206 </span>    <span class="PreProc">break-if-&lt;</span>
+<span id="L207" class="LineNr">207 </span>    <span class="PreProc">return</span> <span class="Constant">0</span>, <span class="Constant">0</span>
+<span id="L208" class="LineNr">208 </span>  <span class="Delimiter">}</span>
+<span id="L209" class="LineNr">209 </span>  <span class="muComment"># we do; actually draw</span>
+<span id="L210" class="LineNr">210 </span>  <a href='106stream.subx.html#L56'>rewind-stream</a> stream
+<span id="L211" class="LineNr">211 </span>  xcurr <span class="SpecialChar">&lt;-</span> copy x
+<span id="L212" class="LineNr">212 </span>  ycurr <span class="SpecialChar">&lt;-</span> copy y
+<span id="L213" class="LineNr">213 </span>  <span class="Delimiter">{</span>
+<span id="L214" class="LineNr">214 </span>    <span class="PreProc">var</span> g/<span class="Constant">eax</span>: grapheme <span class="SpecialChar">&lt;-</span> read-grapheme stream
+<span id="L215" class="LineNr">215 </span>    compare g, <span class="Constant">0xffffffff</span>  <span class="muComment"># end-of-file</span>
+<span id="L216" class="LineNr">216 </span>    <span class="PreProc">break-if-=</span>
+<span id="L217" class="LineNr">217 </span>    <a href='103grapheme.subx.html#L1'>draw-grapheme</a> screen, g, xcurr, ycurr, color
+<span id="L218" class="LineNr">218 </span>    ycurr <span class="SpecialChar">&lt;-</span> add <span class="Constant">0x10</span>  <span class="muComment"># font-height</span>
+<span id="L219" class="LineNr">219 </span>    compare ycurr, ymax
+<span id="L220" class="LineNr">220 </span>    <span class="Delimiter">{</span>
+<span id="L221" class="LineNr">221 </span>      <span class="PreProc">break-if-&lt;</span>
+<span id="L222" class="LineNr">222 </span>      xcurr <span class="SpecialChar">&lt;-</span> add <span class="Constant">8</span>  <span class="muComment"># font-width</span>
+<span id="L223" class="LineNr">223 </span>      ycurr <span class="SpecialChar">&lt;-</span> copy ymin
+<span id="L224" class="LineNr">224 </span>    <span class="Delimiter">}</span>
+<span id="L225" class="LineNr">225 </span>    <span class="PreProc">loop</span>
+<span id="L226" class="LineNr">226 </span>  <span class="Delimiter">}</span>
+<span id="L227" class="LineNr">227 </span>  <a href='103grapheme.subx.html#L86'>set-cursor-position</a> screen, xcurr, ycurr
+<span id="L228" class="LineNr">228 </span>  <span class="PreProc">return</span> xcurr, ycurr
+<span id="L229" class="LineNr">229 </span><span class="Delimiter">}</span>
+<span id="L230" class="LineNr">230 </span>
+<span id="L231" class="LineNr">231 </span><span class="PreProc">fn</span> <span class="muFunction">draw-text-wrapping-down-then-right-over-full-screen</span> screen: (addr screen), text: (addr array byte), x: int, y: int, color: int<span class="PreProc"> -&gt; </span>_/<span class="Constant">eax</span>: int, _/<span class="Constant">ecx</span>: int <span class="Delimiter">{</span>
+<span id="L232" class="LineNr">232 </span>  <span class="PreProc">var</span> cursor-x/<span class="Constant">eax</span>: int <span class="SpecialChar">&lt;-</span> copy <span class="Constant">0</span>
+<span id="L233" class="LineNr">233 </span>  <span class="PreProc">var</span> cursor-y/<span class="Constant">ecx</span>: int <span class="SpecialChar">&lt;-</span> copy <span class="Constant">0</span>
+<span id="L234" class="LineNr">234 </span>  cursor-x, cursor-y <span class="SpecialChar">&lt;-</span> draw-text-wrapping-down-then-right screen, text, <span class="Constant">0</span>, <span class="Constant">0</span>, <span class="Constant">0x400</span>, <span class="Constant">0x300</span>, x, y, color  <span class="muComment"># 1024, 768</span>
+<span id="L235" class="LineNr">235 </span>  <span class="PreProc">return</span> cursor-x, cursor-y
+<span id="L236" class="LineNr">236 </span><span class="Delimiter">}</span>
+<span id="L237" class="LineNr">237 </span>
+<span id="L238" class="LineNr">238 </span><span class="PreProc">fn</span> <span class="muFunction">draw-text-wrapping-down-then-right-from-cursor</span> screen: (addr screen), text: (addr array byte), xmin: int, ymin: int, xmax: int, ymax: int, color: int<span class="PreProc"> -&gt; </span>_/<span class="Constant">eax</span>: int, _/<span class="Constant">ecx</span>: int <span class="Delimiter">{</span>
+<span id="L239" class="LineNr">239 </span>  <span class="PreProc">var</span> cursor-x/<span class="Constant">eax</span>: int <span class="SpecialChar">&lt;-</span> copy <span class="Constant">0</span>
+<span id="L240" class="LineNr">240 </span>  <span class="PreProc">var</span> cursor-y/<span class="Constant">ecx</span>: int <span class="SpecialChar">&lt;-</span> copy <span class="Constant">0</span>
+<span id="L241" class="LineNr">241 </span>  cursor-x, cursor-y <span class="SpecialChar">&lt;-</span> <a href='103grapheme.subx.html#L73'>cursor-position</a> screen
+<span id="L242" class="LineNr">242 </span>  <span class="PreProc">var</span> end-y/<span class="Constant">edx</span>: int <span class="SpecialChar">&lt;-</span> copy cursor-y
+<span id="L243" class="LineNr">243 </span>  end-y <span class="SpecialChar">&lt;-</span> add <span class="Constant">0x10</span>  <span class="muComment"># font-height</span>
+<span id="L244" class="LineNr">244 </span>  compare end-y, ymax
+<span id="L245" class="LineNr">245 </span>  <span class="Delimiter">{</span>
+<span id="L246" class="LineNr">246 </span>    <span class="PreProc">break-if-&lt;</span>
+<span id="L247" class="LineNr">247 </span>    cursor-x <span class="SpecialChar">&lt;-</span> add <span class="Constant">8</span>  <span class="muComment"># font-width</span>
+<span id="L248" class="LineNr">248 </span>    cursor-y <span class="SpecialChar">&lt;-</span> copy ymin
+<span id="L249" class="LineNr">249 </span>  <span class="Delimiter">}</span>
+<span id="L250" class="LineNr">250 </span>  cursor-x, cursor-y <span class="SpecialChar">&lt;-</span> draw-text-wrapping-down-then-right screen, text, xmin, ymin, xmax, ymax, cursor-x, cursor-y, color
+<span id="L251" class="LineNr">251 </span>  <span class="PreProc">return</span> cursor-x, cursor-y
+<span id="L252" class="LineNr">252 </span><span class="Delimiter">}</span>
+<span id="L253" class="LineNr">253 </span>
+<span id="L254" class="LineNr">254 </span><span class="PreProc">fn</span> <span class="muFunction">draw-text-wrapping-down-then-right-from-cursor-over-full-screen</span> screen: (addr screen), text: (addr array byte), color: int<span class="PreProc"> -&gt; </span>_/<span class="Constant">eax</span>: int, _/<span class="Constant">ecx</span>: int <span class="Delimiter">{</span>
+<span id="L255" class="LineNr">255 </span>  <span class="PreProc">var</span> cursor-x/<span class="Constant">eax</span>: int <span class="SpecialChar">&lt;-</span> copy <span class="Constant">0</span>
+<span id="L256" class="LineNr">256 </span>  <span class="PreProc">var</span> cursor-y/<span class="Constant">ecx</span>: int <span class="SpecialChar">&lt;-</span> copy <span class="Constant">0</span>
+<span id="L257" class="LineNr">257 </span>  cursor-x, cursor-y <span class="SpecialChar">&lt;-</span> draw-text-wrapping-down-then-right-from-cursor screen, text, <span class="Constant">0</span>, <span class="Constant">0</span>, <span class="Constant">0x400</span>, <span class="Constant">0x300</span>, color  <span class="muComment"># 1024, 768</span>
+<span id="L258" class="LineNr">258 </span>  <span class="PreProc">return</span> cursor-x, cursor-y
+<span id="L259" class="LineNr">259 </span><span class="Delimiter">}</span>
 </pre>
 </body>
 </html>
diff --git a/html/baremetal/502manhattan-line.mu.html b/html/baremetal/502manhattan-line.mu.html
new file mode 100644
index 00000000..9d2632d1
--- /dev/null
+++ b/html/baremetal/502manhattan-line.mu.html
@@ -0,0 +1,89 @@
+<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN" "http://www.w3.org/TR/html4/strict.dtd">
+<html>
+<head>
+<meta http-equiv="content-type" content="text/html; charset=UTF-8">
+<title>Mu - baremetal/502manhattan-line.mu</title>
+<meta name="Generator" content="Vim/8.1">
+<meta name="plugin-version" content="vim8.1_v1">
+<meta name="syntax" content="none">
+<meta name="settings" content="number_lines,use_css,pre_wrap,no_foldcolumn,expand_tabs,line_ids,prevent_copy=">
+<meta name="colorscheme" content="minimal-light">
+<style type="text/css">
+<!--
+pre { white-space: pre-wrap; font-family: monospace; color: #000000; background-color: #c6c6c6; }
+body { font-size:12pt; font-family: monospace; color: #000000; background-color: #c6c6c6; }
+a { color:inherit; }
+* { font-size:12pt; font-size: 1em; }
+.PreProc { color: #c000c0; }
+.LineNr { }
+.Constant { color: #008787; }
+.SpecialChar { color: #d70000; }
+.Delimiter { color: #c000c0; }
+.muFunction { color: #af5f00; text-decoration: underline; }
+-->
+</style>
+
+<script type='text/javascript'>
+<!--
+
+/* function to open any folds containing a jumped-to line before jumping to it */
+function JumpToLine()
+{
+  var lineNum;
+  lineNum = window.location.hash;
+  lineNum = lineNum.substr(1); /* strip off '#' */
+
+  if (lineNum.indexOf('L') == -1) {
+    lineNum = 'L'+lineNum;
+  }
+  var lineElem = document.getElementById(lineNum);
+  /* Always jump to new location even if the line was hidden inside a fold, or
+   * we corrected the raw number to a line ID.
+   */
+  if (lineElem) {
+    lineElem.scrollIntoView(true);
+  }
+  return true;
+}
+if ('onhashchange' in window) {
+  window.onhashchange = JumpToLine;
+}
+
+-->
+</script>
+</head>
+<body onload='JumpToLine();'>
+<a href='https://github.com/akkartik/mu/blob/main/baremetal/502manhattan-line.mu'>https://github.com/akkartik/mu/blob/main/baremetal/502manhattan-line.mu</a>
+<pre id='vimCodeElement'>
+<span id="L1" class="LineNr"> 1 </span><span class="PreProc">fn</span> <span class="muFunction">draw-box</span> screen: (addr screen), x1: int, y1: int, x2: int, y2: int, color: int <span class="Delimiter">{</span>
+<span id="L2" class="LineNr"> 2 </span>  draw-horizontal-line screen, x1, x2, y1, color
+<span id="L3" class="LineNr"> 3 </span>  draw-vertical-line screen, x1, y1, y2, color
+<span id="L4" class="LineNr"> 4 </span>  draw-horizontal-line screen, x1, x2, y2, color
+<span id="L5" class="LineNr"> 5 </span>  draw-vertical-line screen, x2, y1, y2, color
+<span id="L6" class="LineNr"> 6 </span><span class="Delimiter">}</span>
+<span id="L7" class="LineNr"> 7 </span>
+<span id="L8" class="LineNr"> 8 </span><span class="PreProc">fn</span> <span class="muFunction">draw-horizontal-line</span> screen: (addr screen), x1: int, x2: int, y: int, color: int <span class="Delimiter">{</span>
+<span id="L9" class="LineNr"> 9 </span>  <span class="PreProc">var</span> x/<span class="Constant">eax</span>: int <span class="SpecialChar">&lt;-</span> copy x1
+<span id="L10" class="LineNr">10 </span>  <span class="Delimiter">{</span>
+<span id="L11" class="LineNr">11 </span>    compare x, x2
+<span id="L12" class="LineNr">12 </span>    <span class="PreProc">break-if-&gt;=</span>
+<span id="L13" class="LineNr">13 </span>    <a href='101screen.subx.html#L3'>pixel</a> screen, x, y, color
+<span id="L14" class="LineNr">14 </span>    x <span class="SpecialChar">&lt;-</span> increment
+<span id="L15" class="LineNr">15 </span>    <span class="PreProc">loop</span>
+<span id="L16" class="LineNr">16 </span>  <span class="Delimiter">}</span>
+<span id="L17" class="LineNr">17 </span><span class="Delimiter">}</span>
+<span id="L18" class="LineNr">18 </span>
+<span id="L19" class="LineNr">19 </span><span class="PreProc">fn</span> <span class="muFunction">draw-vertical-line</span> screen: (addr screen), x: int, y1: int, y2: int, color: int <span class="Delimiter">{</span>
+<span id="L20" class="LineNr">20 </span>  <span class="PreProc">var</span> y/<span class="Constant">eax</span>: int <span class="SpecialChar">&lt;-</span> copy y1
+<span id="L21" class="LineNr">21 </span>  <span class="Delimiter">{</span>
+<span id="L22" class="LineNr">22 </span>    compare y, y2
+<span id="L23" class="LineNr">23 </span>    <span class="PreProc">break-if-&gt;=</span>
+<span id="L24" class="LineNr">24 </span>    <a href='101screen.subx.html#L3'>pixel</a> screen, x, y, color
+<span id="L25" class="LineNr">25 </span>    y <span class="SpecialChar">&lt;-</span> increment
+<span id="L26" class="LineNr">26 </span>    <span class="PreProc">loop</span>
+<span id="L27" class="LineNr">27 </span>  <span class="Delimiter">}</span>
+<span id="L28" class="LineNr">28 </span><span class="Delimiter">}</span>
+</pre>
+</body>
+</html>
+<!-- vim: set foldmethod=manual : -->
diff --git a/html/baremetal/boot.hex.html b/html/baremetal/boot.hex.html
index 5a3f3f43..610bcbe1 100644
--- a/html/baremetal/boot.hex.html
+++ b/html/baremetal/boot.hex.html
@@ -15,8 +15,8 @@ body { font-size:12pt; font-family: monospace; color: #000000; background-color:
 a { color:inherit; }
 * { font-size:12pt; font-size: 1em; }
 .subxComment { color: #005faf; }
-.LineNr { }
 .subxS1Comment { color: #0000af; }
+.LineNr { }
 .Folded { color: #080808; background-color: #949494; }
 -->
 </style>
diff --git a/html/baremetal/boot0.hex.html b/html/baremetal/boot0.hex.html
index f619f115..958d5530 100644
--- a/html/baremetal/boot0.hex.html
+++ b/html/baremetal/boot0.hex.html
@@ -14,9 +14,9 @@ pre { white-space: pre-wrap; font-family: monospace; color: #000000; background-
 body { font-size:12pt; font-family: monospace; color: #000000; background-color: #c6c6c6; }
 a { color:inherit; }
 * { font-size:12pt; font-size: 1em; }
+.Todo { color: #000000; background-color: #ffff00; padding-bottom: 1px; }
 .LineNr { }
 .Comment { color: #005faf; }
-.Todo { color: #000000; background-color: #ffff00; padding-bottom: 1px; }
 -->
 </style>
 
diff --git a/html/baremetal/ex2.mu.html b/html/baremetal/ex2.mu.html
index 4dd35a7f..e52e4b88 100644
--- a/html/baremetal/ex2.mu.html
+++ b/html/baremetal/ex2.mu.html
@@ -14,13 +14,13 @@ pre { white-space: pre-wrap; font-family: monospace; color: #000000; background-
 body { font-size:12pt; font-family: monospace; color: #000000; background-color: #c6c6c6; }
 a { color:inherit; }
 * { font-size:12pt; font-size: 1em; }
-.muComment { color: #005faf; }
+.PreProc { color: #c000c0; }
 .LineNr { }
+.Constant { color: #008787; }
 .SpecialChar { color: #d70000; }
 .Delimiter { color: #c000c0; }
 .muFunction { color: #af5f00; text-decoration: underline; }
-.Constant { color: #008787; }
-.PreProc { color: #c000c0; }
+.muComment { color: #005faf; }
 -->
 </style>
 
@@ -68,7 +68,7 @@ if ('onhashchange' in window) {
 <span id="L10" class="LineNr">10 </span><span class="muComment"># Expected output:</span>
 <span id="L11" class="LineNr">11 </span><span class="muComment">#   html/baremetal.png</span>
 <span id="L12" class="LineNr">12 </span>
-<span id="L13" class="LineNr">13 </span><span class="PreProc">fn</span> <span class="muFunction"><a href='ex2.mu.html#L13'>main</a></span> <span class="Delimiter">{</span>
+<span id="L13" class="LineNr">13 </span><span class="PreProc">fn</span> <span class="muFunction">main</span> <span class="Delimiter">{</span>
 <span id="L14" class="LineNr">14 </span>  <span class="PreProc">var</span> y/<span class="Constant">eax</span>: int <span class="SpecialChar">&lt;-</span> copy <span class="Constant">0</span>
 <span id="L15" class="LineNr">15 </span>  <span class="Delimiter">{</span>
 <span id="L16" class="LineNr">16 </span>    compare y, <span class="Constant">0x300</span>  <span class="muComment"># 768</span>
diff --git a/html/baremetal/ex3.mu.html b/html/baremetal/ex3.mu.html
index c9d6fb1f..54cdea24 100644
--- a/html/baremetal/ex3.mu.html
+++ b/html/baremetal/ex3.mu.html
@@ -14,13 +14,13 @@ pre { white-space: pre-wrap; font-family: monospace; color: #000000; background-
 body { font-size:12pt; font-family: monospace; color: #000000; background-color: #c6c6c6; }
 a { color:inherit; }
 * { font-size:12pt; font-size: 1em; }
-.muComment { color: #005faf; }
+.PreProc { color: #c000c0; }
 .LineNr { }
+.Constant { color: #008787; }
 .SpecialChar { color: #d70000; }
 .Delimiter { color: #c000c0; }
 .muFunction { color: #af5f00; text-decoration: underline; }
-.Constant { color: #008787; }
-.PreProc { color: #c000c0; }
+.muComment { color: #005faf; }
 -->
 </style>
 
@@ -69,7 +69,7 @@ if ('onhashchange' in window) {
 <span id="L11" class="LineNr">11 </span><span class="muComment"># Expected output: a new green pixel starting from the top left corner of the</span>
 <span id="L12" class="LineNr">12 </span><span class="muComment"># screen every time you press a key (letter or digit)</span>
 <span id="L13" class="LineNr">13 </span>
-<span id="L14" class="LineNr">14 </span><span class="PreProc">fn</span> <span class="muFunction"><a href='ex3.mu.html#L14'>main</a></span> <span class="Delimiter">{</span>
+<span id="L14" class="LineNr">14 </span><span class="PreProc">fn</span> <span class="muFunction">main</span> <span class="Delimiter">{</span>
 <span id="L15" class="LineNr">15 </span>  <span class="PreProc">var</span> x/<span class="Constant">ecx</span>: int <span class="SpecialChar">&lt;-</span> copy <span class="Constant">0</span>
 <span id="L16" class="LineNr">16 </span>  <span class="PreProc">var</span> y/<span class="Constant">edx</span>: int <span class="SpecialChar">&lt;-</span> copy <span class="Constant">0</span>
 <span id="L17" class="LineNr">17 </span>  <span class="Delimiter">{</span>
diff --git a/html/baremetal/ex4.mu.html b/html/baremetal/ex4.mu.html
index b9c5a36f..dc67e721 100644
--- a/html/baremetal/ex4.mu.html
+++ b/html/baremetal/ex4.mu.html
@@ -14,13 +14,13 @@ pre { white-space: pre-wrap; font-family: monospace; color: #000000; background-
 body { font-size:12pt; font-family: monospace; color: #000000; background-color: #c6c6c6; }
 a { color:inherit; }
 * { font-size:12pt; font-size: 1em; }
-.muComment { color: #005faf; }
+.PreProc { color: #c000c0; }
 .LineNr { }
+.Constant { color: #008787; }
 .SpecialChar { color: #d70000; }
 .Delimiter { color: #c000c0; }
 .muFunction { color: #af5f00; text-decoration: underline; }
-.Constant { color: #008787; }
-.PreProc { color: #c000c0; }
+.muComment { color: #005faf; }
 -->
 </style>
 
@@ -67,7 +67,7 @@ if ('onhashchange' in window) {
 <span id="L9" class="LineNr"> 9 </span><span class="muComment">#</span>
 <span id="L10" class="LineNr">10 </span><span class="muComment"># Expected output: letter 'A' in green near the top-left corner of screen</span>
 <span id="L11" class="LineNr">11 </span>
-<span id="L12" class="LineNr">12 </span><span class="PreProc">fn</span> <span class="muFunction"><a href='ex4.mu.html#L12'>main</a></span> <span class="Delimiter">{</span>
+<span id="L12" class="LineNr">12 </span><span class="PreProc">fn</span> <span class="muFunction">main</span> <span class="Delimiter">{</span>
 <span id="L13" class="LineNr">13 </span>  <span class="PreProc">var</span> g/<span class="Constant">eax</span>: grapheme <span class="SpecialChar">&lt;-</span> copy <span class="Constant">0x41</span>  <span class="muComment"># 'A'</span>
 <span id="L14" class="LineNr">14 </span>  <a href='103grapheme.subx.html#L1'>draw-grapheme</a> <span class="Constant">0</span>, g, <span class="Constant">0x10</span>, <span class="Constant">0x10</span>, <span class="Constant">0xa</span>
 <span id="L15" class="LineNr">15 </span><span class="Delimiter">}</span>
diff --git a/html/baremetal/ex5.mu.html b/html/baremetal/ex5.mu.html
index 95c2f03d..c4321e97 100644
--- a/html/baremetal/ex5.mu.html
+++ b/html/baremetal/ex5.mu.html
@@ -14,12 +14,13 @@ pre { white-space: pre-wrap; font-family: monospace; color: #000000; background-
 body { font-size:12pt; font-family: monospace; color: #000000; background-color: #c6c6c6; }
 a { color:inherit; }
 * { font-size:12pt; font-size: 1em; }
-.muComment { color: #005faf; }
+.PreProc { color: #c000c0; }
 .LineNr { }
+.Constant { color: #008787; }
+.SpecialChar { color: #d70000; }
 .Delimiter { color: #c000c0; }
 .muFunction { color: #af5f00; text-decoration: underline; }
-.Constant { color: #008787; }
-.PreProc { color: #c000c0; }
+.muComment { color: #005faf; }
 -->
 </style>
 
@@ -55,20 +56,22 @@ if ('onhashchange' in window) {
 <body onload='JumpToLine();'>
 <a href='https://github.com/akkartik/mu/blob/main/baremetal/ex5.mu'>https://github.com/akkartik/mu/blob/main/baremetal/ex5.mu</a>
 <pre id='vimCodeElement'>
-<span id="L1" class="LineNr"> 1 </span><span class="muComment"># Draw an ASCII string using the built-in font (GNU unifont)</span>
-<span id="L2" class="LineNr"> 2 </span><span class="muComment">#</span>
-<span id="L3" class="LineNr"> 3 </span><span class="muComment"># To build a disk image:</span>
-<span id="L4" class="LineNr"> 4 </span><span class="muComment">#   ./translate_mu_baremetal baremetal/ex5.mu     # emits disk.img</span>
-<span id="L5" class="LineNr"> 5 </span><span class="muComment"># To run:</span>
-<span id="L6" class="LineNr"> 6 </span><span class="muComment">#   qemu-system-i386 disk.img</span>
-<span id="L7" class="LineNr"> 7 </span><span class="muComment"># Or:</span>
-<span id="L8" class="LineNr"> 8 </span><span class="muComment">#   bochs -f baremetal/boot.bochsrc               # boot.bochsrc loads disk.img</span>
-<span id="L9" class="LineNr"> 9 </span><span class="muComment">#</span>
-<span id="L10" class="LineNr">10 </span><span class="muComment"># Expected output: text in green near the top-left corner of screen</span>
-<span id="L11" class="LineNr">11 </span>
-<span id="L12" class="LineNr">12 </span><span class="PreProc">fn</span> <span class="muFunction"><a href='ex5.mu.html#L12'>main</a></span> <span class="Delimiter">{</span>
-<span id="L13" class="LineNr">13 </span>  <a href='501draw-text.mu.html#L1'>draw-text-rightward</a> <span class="Constant">0</span>, <span class="Constant">&quot;hello from baremetal Mu!&quot;</span>, <span class="Constant">0x10</span>, <span class="Constant">0x10</span>, <span class="Constant">0xa</span>
-<span id="L14" class="LineNr">14 </span><span class="Delimiter">}</span>
+<span id="L1" class="LineNr"> 1 </span><span class="muComment"># Draw a single line of ASCII text using the built-in font (GNU unifont)</span>
+<span id="L2" class="LineNr"> 2 </span><span class="muComment"># Also demonstrates bounds-checking _before_ drawing.</span>
+<span id="L3" class="LineNr"> 3 </span><span class="muComment">#</span>
+<span id="L4" class="LineNr"> 4 </span><span class="muComment"># To build a disk image:</span>
+<span id="L5" class="LineNr"> 5 </span><span class="muComment">#   ./translate_mu_baremetal baremetal/ex5.mu     # emits disk.img</span>
+<span id="L6" class="LineNr"> 6 </span><span class="muComment"># To run:</span>
+<span id="L7" class="LineNr"> 7 </span><span class="muComment">#   qemu-system-i386 disk.img</span>
+<span id="L8" class="LineNr"> 8 </span><span class="muComment"># Or:</span>
+<span id="L9" class="LineNr"> 9 </span><span class="muComment">#   bochs -f baremetal/boot.bochsrc               # boot.bochsrc loads disk.img</span>
+<span id="L10" class="LineNr">10 </span><span class="muComment">#</span>
+<span id="L11" class="LineNr">11 </span><span class="muComment"># Expected output: text in green near the top-left corner of screen</span>
+<span id="L12" class="LineNr">12 </span>
+<span id="L13" class="LineNr">13 </span><span class="PreProc">fn</span> <span class="muFunction">main</span> <span class="Delimiter">{</span>
+<span id="L14" class="LineNr">14 </span>  <span class="PreProc">var</span> dummy/<span class="Constant">eax</span>: int <span class="SpecialChar">&lt;-</span> draw-text-rightward <span class="Constant">0</span>, <span class="Constant">&quot;hello from baremetal Mu!&quot;</span>, <span class="Constant">0x10</span>, <span class="Constant">0x400</span>, <span class="Constant">0x10</span>, <span class="Constant">0xa</span>  <span class="muComment"># xmax = end of screen, plenty of space</span>
+<span id="L15" class="LineNr">15 </span>  dummy <span class="SpecialChar">&lt;-</span> draw-text-rightward <span class="Constant">0</span>, <span class="Constant">&quot;you shouldn't see this&quot;</span>, <span class="Constant">0x10</span>, <span class="Constant">0xa0</span>, <span class="Constant">0x30</span>, <span class="Constant">0x3</span>  <span class="muComment"># xmax = 0xa0, which is too narrow</span>
+<span id="L16" class="LineNr">16 </span><span class="Delimiter">}</span>
 </pre>
 </body>
 </html>
diff --git a/html/baremetal/ex6.mu.html b/html/baremetal/ex6.mu.html
new file mode 100644
index 00000000..810b729b
--- /dev/null
+++ b/html/baremetal/ex6.mu.html
@@ -0,0 +1,94 @@
+<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN" "http://www.w3.org/TR/html4/strict.dtd">
+<html>
+<head>
+<meta http-equiv="content-type" content="text/html; charset=UTF-8">
+<title>Mu - baremetal/ex6.mu</title>
+<meta name="Generator" content="Vim/8.1">
+<meta name="plugin-version" content="vim8.1_v1">
+<meta name="syntax" content="none">
+<meta name="settings" content="number_lines,use_css,pre_wrap,no_foldcolumn,expand_tabs,line_ids,prevent_copy=">
+<meta name="colorscheme" content="minimal-light">
+<style type="text/css">
+<!--
+pre { white-space: pre-wrap; font-family: monospace; color: #000000; background-color: #c6c6c6; }
+body { font-size:12pt; font-family: monospace; color: #000000; background-color: #c6c6c6; }
+a { color:inherit; }
+* { font-size:12pt; font-size: 1em; }
+.PreProc { color: #c000c0; }
+.LineNr { }
+.Constant { color: #008787; }
+.SpecialChar { color: #d70000; }
+.Delimiter { color: #c000c0; }
+.muFunction { color: #af5f00; text-decoration: underline; }
+.muComment { color: #005faf; }
+-->
+</style>
+
+<script type='text/javascript'>
+<!--
+
+/* function to open any folds containing a jumped-to line before jumping to it */
+function JumpToLine()
+{
+  var lineNum;
+  lineNum = window.location.hash;
+  lineNum = lineNum.substr(1); /* strip off '#' */
+
+  if (lineNum.indexOf('L') == -1) {
+    lineNum = 'L'+lineNum;
+  }
+  var lineElem = document.getElementById(lineNum);
+  /* Always jump to new location even if the line was hidden inside a fold, or
+   * we corrected the raw number to a line ID.
+   */
+  if (lineElem) {
+    lineElem.scrollIntoView(true);
+  }
+  return true;
+}
+if ('onhashchange' in window) {
+  window.onhashchange = JumpToLine;
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+<a href='https://github.com/akkartik/mu/blob/main/baremetal/ex6.mu'>https://github.com/akkartik/mu/blob/main/baremetal/ex6.mu</a>
+<pre id='vimCodeElement'>
+<span id="L1" class="LineNr"> 1 </span><span class="muComment"># Drawing ASCII text incrementally.</span>
+<span id="L2" class="LineNr"> 2 </span><span class="muComment">#</span>
+<span id="L3" class="LineNr"> 3 </span><span class="muComment"># To build a disk image:</span>
+<span id="L4" class="LineNr"> 4 </span><span class="muComment">#   ./translate_mu_baremetal baremetal/ex6.mu     # emits disk.img</span>
+<span id="L5" class="LineNr"> 5 </span><span class="muComment"># To run:</span>
+<span id="L6" class="LineNr"> 6 </span><span class="muComment">#   qemu-system-i386 disk.img</span>
+<span id="L7" class="LineNr"> 7 </span><span class="muComment"># Or:</span>
+<span id="L8" class="LineNr"> 8 </span><span class="muComment">#   bochs -f baremetal/boot.bochsrc               # boot.bochsrc loads disk.img</span>
+<span id="L9" class="LineNr"> 9 </span><span class="muComment">#</span>
+<span id="L10" class="LineNr">10 </span><span class="muComment"># Expected output: a box and text that doesn't overflow it</span>
+<span id="L11" class="LineNr">11 </span>
+<span id="L12" class="LineNr">12 </span><span class="PreProc">fn</span> <span class="muFunction">main</span> <span class="Delimiter">{</span>
+<span id="L13" class="LineNr">13 </span>  <span class="muComment"># drawing text within a bounding box</span>
+<span id="L14" class="LineNr">14 </span>  draw-box <span class="Constant">0</span>, <span class="Constant">0xf</span>, <span class="Constant">0x1f</span>, <span class="Constant">0x79</span>, <span class="Constant">0x51</span>, <span class="Constant">0x4</span>
+<span id="L15" class="LineNr">15 </span>  <span class="PreProc">var</span> x/<span class="Constant">eax</span>: int <span class="SpecialChar">&lt;-</span> copy <span class="Constant">0x20</span>
+<span id="L16" class="LineNr">16 </span>  <span class="PreProc">var</span> y/<span class="Constant">ecx</span>: int <span class="SpecialChar">&lt;-</span> copy <span class="Constant">0x20</span>
+<span id="L17" class="LineNr">17 </span>  x, y <span class="SpecialChar">&lt;-</span> draw-text-wrapping-right-then-down <span class="Constant">0</span>, <span class="Constant">&quot;hello &quot;</span>,     <span class="Constant">0x10</span>, <span class="Constant">0x20</span>, <span class="Constant">0x78</span>, <span class="Constant">0x50</span>, x, y, <span class="Constant">0xa</span>  <span class="muComment"># (0x10, 0x20) -&gt; (0x78, 0x50)</span>
+<span id="L18" class="LineNr">18 </span>  x, y <span class="SpecialChar">&lt;-</span> draw-text-wrapping-right-then-down <span class="Constant">0</span>, <span class="Constant">&quot;from &quot;</span>,      <span class="Constant">0x10</span>, <span class="Constant">0x20</span>, <span class="Constant">0x78</span>, <span class="Constant">0x50</span>, x, y, <span class="Constant">0xa</span>
+<span id="L19" class="LineNr">19 </span>  x, y <span class="SpecialChar">&lt;-</span> draw-text-wrapping-right-then-down <span class="Constant">0</span>, <span class="Constant">&quot;baremetal &quot;</span>, <span class="Constant">0x10</span>, <span class="Constant">0x20</span>, <span class="Constant">0x78</span>, <span class="Constant">0x50</span>, x, y, <span class="Constant">0xa</span>
+<span id="L20" class="LineNr">20 </span>  x, y <span class="SpecialChar">&lt;-</span> draw-text-wrapping-right-then-down <span class="Constant">0</span>, <span class="Constant">&quot;Mu!&quot;</span>,        <span class="Constant">0x10</span>, <span class="Constant">0x20</span>, <span class="Constant">0x78</span>, <span class="Constant">0x50</span>, x, y, <span class="Constant">0xa</span>
+<span id="L21" class="LineNr">21 </span>
+<span id="L22" class="LineNr">22 </span>  <span class="muComment"># drawing at the cursor in multiple directions</span>
+<span id="L23" class="LineNr">23 </span>  x, y <span class="SpecialChar">&lt;-</span> draw-text-wrapping-down-then-right-from-cursor-over-full-screen <span class="Constant">0</span>, <span class="Constant">&quot;abc&quot;</span>, <span class="Constant">0xa</span>
+<span id="L24" class="LineNr">24 </span>  x, y <span class="SpecialChar">&lt;-</span> draw-text-wrapping-right-then-down-from-cursor-over-full-screen <span class="Constant">0</span>, <span class="Constant">&quot;def&quot;</span>, <span class="Constant">0xa</span>
+<span id="L25" class="LineNr">25 </span>
+<span id="L26" class="LineNr">26 </span>  <span class="muComment"># test drawing near the edge</span>
+<span id="L27" class="LineNr">27 </span>  x <span class="SpecialChar">&lt;-</span> draw-text-rightward <span class="Constant">0</span>, <span class="Constant">&quot;R&quot;</span>, <span class="Constant">0x3f8</span>, <span class="Constant">0x400</span>, <span class="Constant">0x100</span>, <span class="Constant">0xa</span>
+<span id="L28" class="LineNr">28 </span>  x, y <span class="SpecialChar">&lt;-</span> draw-text-wrapping-right-then-down-from-cursor-over-full-screen <span class="Constant">0</span>, <span class="Constant">&quot;wrapped from R&quot;</span>, <span class="Constant">0xa</span>
+<span id="L29" class="LineNr">29 </span>
+<span id="L30" class="LineNr">30 </span>  x <span class="SpecialChar">&lt;-</span> draw-text-downward <span class="Constant">0</span>, <span class="Constant">&quot;D&quot;</span>, <span class="Constant">0x100</span>, <span class="Constant">0x2f0</span>, <span class="Constant">0x300</span>, <span class="Constant">0xa</span>
+<span id="L31" class="LineNr">31 </span>  x, y <span class="SpecialChar">&lt;-</span> draw-text-wrapping-down-then-right-from-cursor-over-full-screen <span class="Constant">0</span>, <span class="Constant">&quot;wrapped from D&quot;</span>, <span class="Constant">0xa</span>
+<span id="L32" class="LineNr">32 </span><span class="Delimiter">}</span>
+</pre>
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+</html>
+<!-- vim: set foldmethod=manual : -->