503 - start of a solution for drawing pieces

Dog slow, though. Drawing the sprite for a single piece takes 12s or
30ms/pixel for 400 pixels. A third of that is the actual racket overhead
of drawing pixel by pixel, which would in itself be too much. We need
bitblts.

(Black queen pixels derived from http://www.wpclipart.com/recreation/games/chess/chess_set_1,
after scaling down to 40x40 and replacing external white pixels with
transparent ones in Gimp.)

3 files changed, 221 insertions, 28 deletions

diff --git a/chessboard-graphic.mu b/chessboard-graphic.mu
index fd66c852..19607e89 100644
--- a/chessboard-graphic.mu
+++ b/chessboard-graphic.mu
@@ -53,7 +53,165 @@
   (reply result:file-address cursor:list-address)
 ])
 
-(function print-board [
+;; data structure: sprite
+(and-record sprite [
+  width:integer
+  height:integer
+  data:integer-array-address
+])
+
+(address sprite-address (sprite))
+
+(function read-sprite [
+  (default-space:space-address <- new space:literal 30:literal)
+  (print-primitive (("  init-list\n" literal)))
+(q-pbm:list-address <- init-list
+  0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal
+  0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal
+  0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 2:literal 2:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal
+  0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 2:literal 1:literal 1:literal 2:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal
+  0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 2:literal 2:literal 1:literal 2:literal 0:literal 0:literal 0:literal 0:literal 0:literal 2:literal 1:literal 1:literal 2:literal 0:literal 0:literal 0:literal 0:literal 0:literal 2:literal 1:literal 2:literal 2:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal
+  0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 2:literal 1:literal 1:literal 2:literal 0:literal 0:literal 0:literal 0:literal 0:literal 2:literal 1:literal 1:literal 2:literal 0:literal 0:literal 0:literal 0:literal 0:literal 2:literal 1:literal 1:literal 2:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal
+  0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 2:literal 1:literal 1:literal 2:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 2:literal 2:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 2:literal 1:literal 1:literal 2:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal
+  0:literal 0:literal 2:literal 2:literal 2:literal 0:literal 0:literal 0:literal 0:literal 2:literal 2:literal 2:literal 2:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 2:literal 2:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 2:literal 2:literal 2:literal 2:literal 0:literal 0:literal 0:literal 0:literal 2:literal 2:literal 2:literal 0:literal 0:literal
+  0:literal 2:literal 1:literal 1:literal 2:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 2:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 2:literal 2:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 2:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 2:literal 1:literal 1:literal 2:literal 0:literal
+  0:literal 2:literal 1:literal 1:literal 2:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 1:literal 2:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 2:literal 2:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 2:literal 1:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 2:literal 1:literal 1:literal 2:literal 0:literal
+  0:literal 2:literal 2:literal 1:literal 2:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 1:literal 2:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 2:literal 2:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 2:literal 1:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 2:literal 1:literal 2:literal 2:literal 0:literal
+  0:literal 0:literal 0:literal 2:literal 2:literal 0:literal 0:literal 0:literal 0:literal 0:literal 2:literal 1:literal 2:literal 0:literal 0:literal 0:literal 0:literal 0:literal 2:literal 1:literal 1:literal 2:literal 0:literal 0:literal 0:literal 0:literal 0:literal 2:literal 1:literal 2:literal 0:literal 0:literal 0:literal 0:literal 0:literal 2:literal 2:literal 0:literal 0:literal 0:literal
+  0:literal 0:literal 0:literal 2:literal 2:literal 0:literal 0:literal 0:literal 0:literal 0:literal 2:literal 1:literal 1:literal 2:literal 0:literal 0:literal 0:literal 0:literal 2:literal 1:literal 1:literal 2:literal 0:literal 0:literal 0:literal 0:literal 2:literal 1:literal 1:literal 2:literal 0:literal 0:literal 0:literal 0:literal 0:literal 2:literal 2:literal 0:literal 0:literal 0:literal
+  0:literal 0:literal 0:literal 2:literal 1:literal 2:literal 0:literal 0:literal 0:literal 0:literal 2:literal 1:literal 1:literal 2:literal 0:literal 0:literal 0:literal 0:literal 2:literal 1:literal 1:literal 2:literal 0:literal 0:literal 0:literal 0:literal 2:literal 1:literal 1:literal 2:literal 0:literal 0:literal 0:literal 0:literal 2:literal 1:literal 2:literal 0:literal 0:literal 0:literal
+  0:literal 0:literal 0:literal 2:literal 1:literal 2:literal 0:literal 0:literal 0:literal 0:literal 2:literal 1:literal 1:literal 2:literal 0:literal 0:literal 0:literal 0:literal 2:literal 1:literal 1:literal 2:literal 0:literal 0:literal 0:literal 0:literal 2:literal 1:literal 1:literal 2:literal 0:literal 0:literal 0:literal 0:literal 2:literal 1:literal 2:literal 0:literal 0:literal 0:literal
+  0:literal 0:literal 0:literal 0:literal 1:literal 2:literal 2:literal 0:literal 0:literal 0:literal 2:literal 1:literal 1:literal 1:literal 2:literal 0:literal 0:literal 0:literal 2:literal 1:literal 1:literal 2:literal 0:literal 0:literal 0:literal 2:literal 1:literal 1:literal 1:literal 2:literal 0:literal 0:literal 0:literal 2:literal 2:literal 1:literal 0:literal 0:literal 0:literal 0:literal
+  0:literal 0:literal 0:literal 0:literal 2:literal 1:literal 2:literal 0:literal 0:literal 0:literal 2:literal 1:literal 1:literal 1:literal 2:literal 0:literal 0:literal 0:literal 2:literal 1:literal 1:literal 2:literal 0:literal 0:literal 0:literal 2:literal 1:literal 1:literal 1:literal 2:literal 0:literal 0:literal 0:literal 2:literal 1:literal 2:literal 0:literal 0:literal 0:literal 0:literal
+  0:literal 0:literal 0:literal 0:literal 2:literal 1:literal 1:literal 2:literal 0:literal 0:literal 2:literal 1:literal 1:literal 1:literal 1:literal 2:literal 0:literal 2:literal 1:literal 1:literal 1:literal 1:literal 2:literal 0:literal 2:literal 1:literal 1:literal 1:literal 1:literal 2:literal 0:literal 0:literal 2:literal 1:literal 1:literal 2:literal 0:literal 0:literal 0:literal 0:literal
+  0:literal 0:literal 0:literal 0:literal 2:literal 1:literal 1:literal 2:literal 0:literal 0:literal 2:literal 1:literal 1:literal 1:literal 1:literal 2:literal 0:literal 2:literal 1:literal 1:literal 1:literal 1:literal 2:literal 0:literal 2:literal 1:literal 1:literal 1:literal 1:literal 2:literal 0:literal 0:literal 2:literal 1:literal 1:literal 2:literal 0:literal 0:literal 0:literal 0:literal
+  0:literal 0:literal 0:literal 0:literal 2:literal 1:literal 1:literal 1:literal 2:literal 0:literal 2:literal 1:literal 1:literal 1:literal 1:literal 2:literal 0:literal 2:literal 1:literal 1:literal 1:literal 1:literal 2:literal 0:literal 2:literal 1:literal 1:literal 1:literal 1:literal 2:literal 0:literal 2:literal 1:literal 1:literal 1:literal 2:literal 0:literal 0:literal 0:literal 0:literal
+  0:literal 0:literal 0:literal 0:literal 2:literal 1:literal 1:literal 1:literal 2:literal 0:literal 2:literal 1:literal 1:literal 1:literal 1:literal 1:literal 2:literal 2:literal 1:literal 1:literal 1:literal 1:literal 2:literal 2:literal 1:literal 1:literal 1:literal 1:literal 1:literal 2:literal 0:literal 2:literal 1:literal 1:literal 1:literal 2:literal 0:literal 0:literal 0:literal 0:literal
+  0:literal 0:literal 0:literal 0:literal 2:literal 1:literal 1:literal 1:literal 1:literal 2:literal 2:literal 1:literal 1:literal 1:literal 1:literal 1:literal 2:literal 1:literal 1:literal 1:literal 1:literal 1:literal 1:literal 2:literal 1:literal 1:literal 1:literal 1:literal 1:literal 2:literal 2:literal 1:literal 1:literal 1:literal 1:literal 2:literal 0:literal 0:literal 0:literal 0:literal
+  0:literal 0:literal 0:literal 0:literal 2:literal 1:literal 1:literal 1:literal 1:literal 2:literal 2:literal 1:literal 1:literal 1:literal 1:literal 1:literal 2:literal 1:literal 1:literal 1:literal 1:literal 1:literal 1:literal 2:literal 1:literal 1:literal 1:literal 1:literal 1:literal 2:literal 2:literal 1:literal 1:literal 1:literal 1:literal 2:literal 0:literal 0:literal 0:literal 0:literal
+  0:literal 0:literal 0:literal 0:literal 0:literal 1:literal 1:literal 1:literal 1:literal 2:literal 2:literal 1:literal 1:literal 1:literal 1:literal 1:literal 1:literal 1:literal 1:literal 1:literal 1:literal 1:literal 1:literal 1:literal 1:literal 1:literal 1:literal 1:literal 1:literal 2:literal 2:literal 1:literal 1:literal 1:literal 1:literal 0:literal 0:literal 0:literal 0:literal 0:literal
+  0:literal 0:literal 0:literal 0:literal 0:literal 1:literal 1:literal 1:literal 1:literal 1:literal 1:literal 1:literal 1:literal 1:literal 1:literal 1:literal 1:literal 1:literal 1:literal 1:literal 1:literal 1:literal 1:literal 1:literal 1:literal 1:literal 1:literal 1:literal 1:literal 1:literal 1:literal 1:literal 1:literal 1:literal 1:literal 0:literal 0:literal 0:literal 0:literal 0:literal
+  0:literal 0:literal 0:literal 0:literal 0:literal 2:literal 2:literal 1:literal 1:literal 1:literal 1:literal 1:literal 1:literal 1:literal 1:literal 2:literal 2:literal 2:literal 2:literal 2:literal 2:literal 2:literal 2:literal 2:literal 2:literal 1:literal 1:literal 1:literal 1:literal 1:literal 1:literal 1:literal 1:literal 2:literal 2:literal 0:literal 0:literal 0:literal 0:literal 0:literal
+  0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 2:literal 1:literal 1:literal 1:literal 1:literal 1:literal 2:literal 2:literal 2:literal 2:literal 2:literal 2:literal 2:literal 2:literal 2:literal 2:literal 2:literal 2:literal 2:literal 0:literal 2:literal 2:literal 1:literal 1:literal 1:literal 1:literal 1:literal 2:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal
+  0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 2:literal 1:literal 2:literal 2:literal 1:literal 2:literal 2:literal 2:literal 2:literal 2:literal 2:literal 2:literal 2:literal 2:literal 2:literal 2:literal 2:literal 2:literal 2:literal 2:literal 2:literal 2:literal 2:literal 2:literal 1:literal 2:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal
+  0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 2:literal 2:literal 2:literal 2:literal 1:literal 1:literal 1:literal 1:literal 1:literal 1:literal 1:literal 1:literal 1:literal 1:literal 1:literal 1:literal 1:literal 1:literal 1:literal 1:literal 2:literal 2:literal 2:literal 2:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal
+  0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 2:literal 1:literal 1:literal 1:literal 1:literal 1:literal 2:literal 2:literal 2:literal 2:literal 2:literal 2:literal 2:literal 2:literal 2:literal 2:literal 2:literal 2:literal 1:literal 1:literal 1:literal 1:literal 1:literal 2:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal
+  0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 1:literal 1:literal 1:literal 2:literal 2:literal 2:literal 2:literal 2:literal 2:literal 2:literal 2:literal 2:literal 2:literal 2:literal 2:literal 2:literal 2:literal 2:literal 2:literal 1:literal 1:literal 1:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal
+  0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 2:literal 2:literal 2:literal 2:literal 2:literal 2:literal 2:literal 1:literal 1:literal 1:literal 1:literal 1:literal 1:literal 1:literal 1:literal 2:literal 2:literal 2:literal 2:literal 2:literal 2:literal 2:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal
+  0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 2:literal 2:literal 2:literal 2:literal 1:literal 1:literal 1:literal 1:literal 1:literal 2:literal 2:literal 2:literal 2:literal 1:literal 1:literal 1:literal 1:literal 1:literal 2:literal 2:literal 2:literal 2:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal
+  0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 1:literal 1:literal 1:literal 2:literal 2:literal 2:literal 2:literal 2:literal 2:literal 2:literal 2:literal 2:literal 2:literal 2:literal 2:literal 2:literal 2:literal 2:literal 2:literal 1:literal 1:literal 1:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal
+  0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 2:literal 1:literal 2:literal 2:literal 2:literal 2:literal 2:literal 2:literal 2:literal 2:literal 2:literal 2:literal 2:literal 2:literal 2:literal 2:literal 2:literal 2:literal 2:literal 2:literal 2:literal 2:literal 1:literal 2:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal
+  0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 2:literal 2:literal 2:literal 2:literal 2:literal 2:literal 1:literal 1:literal 1:literal 1:literal 1:literal 1:literal 1:literal 1:literal 1:literal 1:literal 1:literal 1:literal 2:literal 2:literal 2:literal 2:literal 2:literal 2:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal
+  0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 2:literal 2:literal 1:literal 1:literal 1:literal 1:literal 1:literal 1:literal 1:literal 1:literal 1:literal 1:literal 1:literal 1:literal 1:literal 1:literal 1:literal 1:literal 1:literal 1:literal 2:literal 2:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal
+  0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 2:literal 2:literal 2:literal 2:literal 2:literal 2:literal 2:literal 2:literal 2:literal 2:literal 2:literal 2:literal 2:literal 2:literal 2:literal 2:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal
+  0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal
+  0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal 0:literal)
+  (print-primitive (("  init-list done\n" literal)))
+;?   (pbm:list-address <- next-input)
+  (result:sprite-address <- new sprite:literal)
+  (w:integer-address <- get-address result:sprite-address/deref width:offset)
+  (w:integer-address/deref <- copy 40:literal)
+  (print-primitive w:integer-address/deref)
+  (h:integer-address <- get-address result:sprite-address/deref height:offset)
+  (h:integer-address/deref <- copy 40:literal)
+  (print-primitive h:integer-address/deref)
+  (capacity:integer <- multiply w:integer-address/deref h:integer-address/deref)
+  (buf:integer-array-address-address <- get-address result:sprite-address/deref data:offset)
+  (print-primitive (("  list-to-array\n" literal)))
+  (buf:integer-array-address-address/deref <- list-to-array capacity:integer q-pbm:list-address)
+  (print-primitive (("  read-sprite done\n" literal)))
+  (reply result:sprite-address)
+])
+
+(function next-int-from-list [
+  (default-space:space-address <- new space:literal 30:literal)
+  (curr:list-address <- next-input)
+  (x:tagged-value-address <- list-value-address curr:list-address)
+  (result:integer <- get x:tagged-value-address/deref payload:offset)  ; unsafe
+  (next:list-address <- list-next curr:list-address)
+  (reply result:integer next:list-address)
+])
+
+(function list-to-array [
+  (default-space:space-address <- new space:literal 30:literal)
+  (size:integer <- next-input)
+  (in:list-address <- next-input)
+  (result:integer-array-address <- new integer-array:literal size:integer)
+  (i:integer <- copy 0:literal)
+  { begin
+    (done?:boolean <- greater-or-equal i:integer size:integer)
+    (break-if done?:boolean)
+    (assert in:list-address (("insufficient elements in list" literal)))
+    (src:tagged-value-address <- list-value-address in:list-address)
+    (dest:integer-address <- index-address result:integer-array-address/deref i:integer)
+    (dest:integer-address/deref <- get src:tagged-value-address/deref payload:offset)
+    (i:integer <- add i:integer 1:literal)
+    (in:list-address <- list-next in:list-address)
+    (loop)
+  }
+  (reply result:integer-array-address)
+])
+
+(function draw-sprite [
+  (default-space:space-address <- new space:literal 30:literal)
+  (origx:integer <- next-input)  ; screen
+  (origy:integer <- next-input)
+  (img:sprite-address <- next-input)
+  (buf:integer-array-address <- get img:sprite-address/deref data:offset)
+  (w:integer <- get img:sprite-address/deref width:offset)  ; sprite
+  (h:integer <- get img:sprite-address/deref height:offset)
+  (xmax:integer <- add w:integer origx:integer)  ; screen
+  (ymax:integer <- add h:integer origy:integer)
+  (y:integer <- copy origy:integer)  ; screen
+  (idx:integer <- copy 0:literal)  ; sprite
+;?   (print-primitive y:integer)
+;?   (print-primitive ((" -> " literal)))
+;?   (print-primitive ymax:integer)
+;?   (print-primitive (("\n" literal)))
+  { begin  ; for y from origy to ymax
+    (done?:boolean <- greater-or-equal y:integer ymax:integer)
+    (break-if done?:boolean)
+;?     (print-primitive (("  y: " literal)))
+;?     (print-primitive y:integer)
+;?     (print-primitive (("\n" literal)))
+    (x:integer <- copy origx:integer)
+    { begin  ; for x from origx to xmax
+      (done?:boolean <- greater-or-equal x:integer xmax:integer)
+      (break-if done?:boolean)
+;?       (print-primitive (("    x: " literal)))
+;?       (print-primitive x:integer)
+;?       (print-primitive (("\n" literal)))
+      { begin  ; switch sprite[x][y]
+        (color:integer <- index buf:integer-array-address/deref idx:integer)
+        { begin
+          (transparent?:boolean <- equal color:integer 0:literal)
+          (break-unless transparent?:boolean)
+          ; do nothing
+          (break 2:blocks)
+        }
+        { begin
+          (white?:boolean <- equal color:integer 1:literal)
+          (break-unless white?:boolean)
+          (point x:integer y:integer (("white" literal)))
+          (break 2:blocks)
+        }
+        { begin
+          (black?:boolean <- equal color:integer 2:literal)
+          (break-unless black?:boolean)
+          (point x:integer y:integer (("black" literal)))
+          (break 2:blocks)
+        }
+      }
+      (x:integer <- add x:integer 1:literal)
+      (idx:integer <- add idx:integer 1:literal)
+      (loop)
+    }
+    (y:integer <- add y:integer 1:literal)
+    (loop)
+  }
+])
+
+(function draw-board [
   (default-space:space-address <- new space:literal 30:literal)
   (b:board-address <- next-input)
   (y:integer <- copy 0:literal)
@@ -71,13 +229,17 @@
       (f:file-address <- index b:board-address/deref col:integer)
       (s:square <- index f:file-address/deref row:integer)
       { begin
-        ; print black squares, leave others white
-        ; todo: print pieces
-        (t1:integer <- add row:integer col:integer)
-        (_ t2:integer <- divide-with-remainder t1:integer 2:literal)
-        (black?:boolean <- equal t2:integer 1:literal)
-        (break-if black?:boolean)
-        (rectangle x:integer y:integer 40:literal 40:literal (("black" literal)))
+        { begin
+          ; print black squares, leave others white
+          ; todo: print pieces
+          (t1:integer <- add row:integer col:integer)
+          (_ t2:integer <- divide-with-remainder t1:integer 2:literal)
+          (black?:boolean <- equal t2:integer 1:literal)
+          (break-if black?:boolean)
+          (rectangle x:integer y:integer 40:literal 40:literal (("dark gray" literal)))
+          (break 2:blocks)
+        }
+        (rectangle x:integer y:integer 40:literal 40:literal (("light gray" literal)))
       }
       (col:integer <- add col:integer 1:literal)
       (x:integer <- add x:integer 40:literal)
@@ -108,14 +270,25 @@
 (function main [
   (default-space:space-address <- new space:literal 30:literal)
   (b:board-address <- read-board)
-  (graphics-on)
+  (graphics-on (("chessboard" literal)) 320:literal 320:literal)
 ;?   (rectangle 0:literal 0:literal 100:literal 200:literal (("black" literal)))
 ;?   (wait-for-key)
 ;?   (reply)
   { begin
     (clear-screen)
-    (print-board b:board-address)
-    (wait-for-mouse)
+;?     (draw-board b:board-address)
+    (print-primitive (("read-sprite\n" literal)))
+    (x:sprite-address <- read-sprite)
+    (print-primitive (("draw-sprite\n" literal)))
+    (foo)
+    (draw-sprite 0:literal 0:literal x:sprite-address)
+;?     (print-primitive (("done\n" literal)))
+;?     (wait-for-key)
+    (break)
+    (image (("Q3.png" literal)) 0:literal 0:literal)
+    (x:integer <- color-at 1:literal 1:literal)
+    (print-primitive x:integer)
+;?     (wait-for-mouse)
 ;?     (m:move-address <- read-move)
 ;?     (b:board-address <- make-move b:board-address m:move-address)
 ;?     (loop)
diff --git a/graphics.mu b/graphics.mu
index c4520c8f..5f19367b 100644
--- a/graphics.mu
+++ b/graphics.mu
@@ -1,13 +1,10 @@
 ; open a viewport, print coordinates of mouse clicks
 ; currently need to ctrl-c to exit after closing the viewport
 (function main [
-  (graphics-on)
+  (graphics-on (("practice" literal)) 300:literal 300:literal)
   { begin
     (pos:integer-integer-pair click?:boolean <- mouse-position)
-    { begin
-      (break-if click?:boolean)
-      (loop 2:blocks)
-    }
+    (loop-unless click?:boolean)
     (x:integer <- get pos:integer-integer-pair 0:offset)
     (y:integer <- get pos:integer-integer-pair 1:offset)
     (print-primitive x:integer)
diff --git a/mu.arc b/mu.arc
index 80d71e0d..85a96226 100644
--- a/mu.arc
+++ b/mu.arc
@@ -25,6 +25,7 @@
          (+ b 1)))))
 
 (def print-times()
+  (prn (current-process-milliseconds))
   (prn "gc " (current-gc-milliseconds))
   (each (name time) (tablist times*)
     (prn name " " time)))
@@ -58,14 +59,16 @@
   (= curr-trace-file* filename))
 
 (= dump-trace* nil)
-(def trace (label . args)
-  (when (or (is dump-trace* t)
-            (and dump-trace* (is label "-"))
-            (and dump-trace* (pos label dump-trace*!whitelist))
-            (and dump-trace* (no dump-trace*!whitelist) (~pos label dump-trace*!blacklist)))
-    (apply prn label ": " args))
-  (enq (list label (apply tostring:prn args))
-       traces*))
+(mac trace (label . args)
+     nil)
+;? (def trace (label . args)
+;?   (when (or (is dump-trace* t)
+;?             (and dump-trace* (is label "-"))
+;?             (and dump-trace* (pos label dump-trace*!whitelist))
+;?             (and dump-trace* (no dump-trace*!whitelist) (~pos label dump-trace*!blacklist)))
+;?     (apply prn label ": " args))
+;?   (enq (list label (apply tostring:prn args))
+;?        traces*))
 
 (redef tr args  ; why am I still returning to prn when debugging? Will this help?
   (do1 nil
@@ -385,7 +388,7 @@
 (= Viewport nil)
 
 ; run instructions from 'routine*' for 'time-slice'
-(def run-for-time-slice (time-slice)
+(deftimed run-for-time-slice (time-slice)
   (point return
     (for ninstrs 0 (< ninstrs time-slice) (++ ninstrs)
       (if (empty body.routine*) (err "@stack.routine*.0!fn-name not defined"))
@@ -611,7 +614,8 @@
                 graphics-on
                   (do1 nil
                     ($.open-graphics)
-                    (= Viewport ($.open-viewport "screen" 320 320)))
+                    (= Viewport ($.open-viewport (m arg.0)  ; name
+                                                 (m arg.1) (m arg.2))))  ; width height
                 graphics-off
                   (do1 nil
                     ($.close-viewport Viewport)  ; why doesn't this close the window? works in naked racket. not racket vs arc.
@@ -632,6 +636,25 @@
                         ($.make-posn (m arg.0) (m arg.1))  ; origin
                         (m arg.2)  (m arg.3)  ; width height
                         (m arg.4)))  ; color
+                point
+                  (do1 nil
+;?                     (let t0 (msec)
+                    (($.draw-pixel Viewport) ($.make-posn (m arg.0) (m arg.1))
+                                             (m arg.2))
+;?                     (update-time "point" t0)
+                    )  ; color
+;?                     )
+
+                image
+                  (do1 nil
+                    (($.draw-pixmap Viewport) (m arg.0)  ; filename
+                                              ($.make-posn (m arg.1) (m arg.2))))
+                color-at
+                  (let pixel (($.get-color-pixel Viewport) ($.make-posn (m arg.0) (m arg.1)))
+                    (prn ($.rgb-red pixel) " " ($.rgb-blue pixel) " " ($.rgb-green pixel))
+                    ($:rgb-red pixel))
+                foo
+                  (= times* (table))
 
                 ; user-defined functions
                 next-input
@@ -1813,9 +1836,9 @@
 ;?   (prn function*!factorial)
   (run 'main)
   (if ($.current-charterm) ($.close-charterm))
-  (prn "\nmemory: " int-canon.memory*)
+;?   (prn "\nmemory: " int-canon.memory*)
   (each routine completed-routines*
     (aif rep.routine!error (prn "error - " it)))
 )
 (reset)
-;? (print-times)
+(print-times)