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authorKartik K. Agaram <vc@akkartik.com>2021-07-11 03:10:53 -0700
committerKartik K. Agaram <vc@akkartik.com>2021-07-11 03:14:17 -0700
commit430dd67cb232b51902ee849cf7cfbedc75aa938b (patch)
tree7814ca9a728fcf36ef4587f723fdf5749b8a4edf /500fake-screen.mu
parenteb6cee60221e86119b696db5156457b2b49297ec (diff)
downloadmu-430dd67cb232b51902ee849cf7cfbedc75aa938b.tar.gz
dither 256-level greyscale to 8-level greyscale
Diffstat (limited to '500fake-screen.mu')
0 files changed, 0 insertions, 0 deletions
ding-left: 5px; padding-right: 5px; } .highlight .hll { background-color: #ffffcc } .highlight .c { color: #888888 } /* Comment */ .highlight .err { color: #a61717; background-color: #e3d2d2 } /* Error */ .highlight .k { color: #008800; font-weight: bold } /* Keyword */ .highlight .ch { color: #888888 } /* Comment.Hashbang */ .highlight .cm { color: #888888 } /* Comment.Multiline */ .highlight .cp { color: #cc0000; font-weight: bold } /* Comment.Preproc */ .highlight .cpf { color: #888888 } /* Comment.PreprocFile */ .highlight .c1 { color: #888888 } /* Comment.Single */ .highlight .cs { color: #cc0000; font-weight: bold; background-color: #fff0f0 } /* Comment.Special */ .highlight .gd { color: #000000; background-color: #ffdddd } /* Generic.Deleted */ .highlight .ge { font-style: italic } /* Generic.Emph */ .highlight .ges { font-weight: bold; font-style: italic } /* Generic.EmphStrong */ .highlight .gr { color: #aa0000 } /* Generic.Error */ .highlight .gh { color: #333333 } /* Generic.Heading */ .highlight .gi { color: #000000; background-color: #ddffdd } /* Generic.Inserted */ .highlight .go { color: #888888 } /* Generic.Output */ .highlight .gp { color: #555555 } /* Generic.Prompt */ .highlight .gs { font-weight: bold } /* Generic.Strong */ .highlight .gu { color: #666666 } /* Generic.Subheading */ .highlight .gt { color: #aa0000 } /* Generic.Traceback */ .highlight .kc { color: #008800; font-weight: bold } /* Keyword.Constant */ .highlight .kd { color: #008800; font-weight: bold } /* Keyword.Declaration */ .highlight .kn { color: #008800; font-weight: bold } /* Keyword.Namespace */ .highlight .kp { color: #008800 } /* Keyword.Pseudo */ .highlight .kr { color: #008800; font-weight: bold } /* Keyword.Reserved */ .highlight .kt { color: #888888; font-weight: bold } /* Keyword.Type */ .highlight .m { color: #0000DD; font-weight: bold } /* Literal.Number */ .highlight .s { color: #dd2200; background-color: #fff0f0 } /* Literal.String */ .highlight .na { color: #336699 } /* Name.Attribute */ .highlight .nb { color: #003388 } /* Name.Builtin */ .highlight .nc { color: #bb0066; font-weight: bold } /* Name.Class */ .highlight .no { color: #003366; font-weight: bold } /* Name.Constant */ .highlight .nd { color: #555555 } /* Name.Decorator */ .highlight .ne { color: #bb0066; font-weight: bold } /* Name.Exception */ .highlight .nf { color: #0066bb; font-weight: bold } /* Name.Function */ .highlight .nl { color: #336699; font-style: italic } /* Name.Label */ .highlight .nn { color: #bb0066; font-weight: bold } /* Name.Namespace */ .highlight .py { color: #336699; font-weight: bold } /* Name.Property */ .highlight .nt { color: #bb0066; font-weight: bold } /* Name.Tag */ .highlight .nv { color: #336699 } /* Name.Variable */ .highlight .ow { color: #008800 } /* Operator.Word */ .highlight .w { color: #bbbbbb } /* Text.Whitespace */ .highlight .mb { color: #0000DD; font-weight: bold } /* Literal.Number.Bin */ .highlight .mf { color: #0000DD; font-weight: bold } /* Literal.Number.Float */ .highlight .mh { color: #0000DD; font-weight: bold } /* Literal.Number.Hex */ .highlight .mi { color: #0000DD; font-weight: bold } /* Literal.Number.Integer */ .highlight .mo { color: #0000DD; font-weight: bold } /* Literal.Number.Oct */ .highlight .sa { color: #dd2200; background-color: #fff0f0 } /* Literal.String.Affix */ .highlight .sb { color: #dd2200; background-color: #fff0f0 } /* Literal.String.Backtick */ .highlight .sc { color: #dd2200; background-color: #fff0f0 } /* Literal.String.Char */ .highlight .dl { color: #dd2200; background-color: #fff0f0 } /* Literal.String.Delimiter */ .highlight .sd { color: #dd2200; background-color: #fff0f0 } /* Literal.String.Doc */ .highlight .s2 { color: #dd2200; background-color: #fff0f0 } /* Literal.String.Double */ .highlight .se { color: #0044dd; background-color: #fff0f0 } /* Literal.String.Escape */ .highlight .sh { color: #dd2200; background-color: #fff0f0 } /* Literal.String.Heredoc */ .highlight .si { color: #3333bb; background-color: #fff0f0 } /* Literal.String.Interpol */ .highlight .sx { color: #22bb22; background-color: #f0fff0 } /* Literal.String.Other */ .highlight .sr { color: #008800; background-color: #fff0ff } /* Literal.String.Regex */ .highlight .s1 { color: #dd2200; background-color: #fff0f0 } /* Literal.String.Single */ .highlight .ss { color: #aa6600; background-color: #fff0f0 } /* Literal.String.Symbol */ .highlight .bp { color: #003388 } /* Name.Builtin.Pseudo */ .highlight .fm { color: #0066bb; font-weight: bold } /* Name.Function.Magic */ .highlight .vc { color: #336699 } /* Name.Variable.Class */ .highlight .vg { color: #dd7700 } /* Name.Variable.Global */ .highlight .vi { color: #3333bb } /* Name.Variable.Instance */ .highlight .vm { color: #336699 } /* Name.Variable.Magic */ .highlight .il { color: #0000DD; font-weight: bold } /* Literal.Number.Integer.Long */
# Listing 7 of https://raytracing.github.io/books/RayTracingInOneWeekend.html
#
# To run (on Linux):
#   $ git clone https://github.com/akkartik/mu
#   $ cd mu
#   $ ./translate_mu apps/raytracing/2.mu
#   $ ./a.elf > 2.ppm

fn main -> _/ebx: int {
  print-string 0, "P3\n256 256\n255\n"
  var _four/edx: int <- copy 4
  var four/xmm1: float <- convert _four
  var one-fourth/xmm1: float <- reciprocal four
  var max/edx: int <- copy 0xff
  var image-size/xmm2: float <- convert max
  var j/ecx: int <- copy 0xff
  {
    compare j, 0
    break-if-<
    var i/eax: int <- copy 0
    {
      compare i, 0xff
      break-if->
      var c: rgb
      # compute r
      var tmp/xmm0: float <- convert i
      tmp <- divide image-size
      var r-addr/edx: (addr float) <- get c, r
      copy-to *r-addr, tmp
#?       var tmp2/ebx: int <- reinterpret *r-addr
#?       print-int32-hex 0, tmp2
#?       print-string 0, "\n"
      # compute g
      tmp <- convert j
      tmp <- divide image-size
      var g-addr/edx: (addr float) <- get c, g
      copy-to *g-addr, tmp
      # compute b
      var b-addr/edx: (addr float) <- get c, b
      copy-to *b-addr, one-fourth
      # emit
      var c-addr/edx: (addr rgb) <- address c
      print-rgb 0, c-addr
      i <- increment
      loop
    }
    j <- decrement
    loop
  }
  return 0
}

type rgb {
  # components normalized to within [0.0, 1.0]
  r: float
  g: float
  b: float
}

# print translating to [0, 256)
fn print-rgb screen: (addr screen), _c: (addr rgb) {
  var c/esi: (addr rgb) <- copy _c
  var n/ecx: int <- copy 0xff  # turns out 255 works just as well as 255.999, which is lucky because we don't have floating-point literals
  var xn/xmm1: float <- convert n
  # print 255 * c->r
  var result/xmm0: float <- copy xn
  var src-addr/eax: (addr float) <- get c, r
  result <- multiply *src-addr
  var result-int/edx: int <- convert result
  print-int32-decimal screen, result-int
  print-string screen, " "
  # print 255 * c->g
  src-addr <- get c, g
  result <- copy xn
  result <- multiply *src-addr
  result-int <- convert result
  print-int32-decimal screen, result-int
  print-string screen, " "
  # print 255 * c->b
  src-addr <- get c, b
  result <- copy xn
  result <- multiply *src-addr
  result-int <- convert result
  print-int32-decimal screen, result-int
  print-string screen, "\n"
}