Munching squares in Maclisp, for display terminals.

src/lars/munch.lisp

@@ -0,0 +1,29 @@
+(defun munch-compute (size n list)
+  (loop with half = (quotient size 2)
+        and result = nil
+        for i from 0 below (times n n) by n
+        for w = (subseq list i n) do
+	    (loop for (x y) in w do
+		  (push (list x y) result)
+		  (push (list (plus x half) (plus y half)) result))
+	    (loop for (x y) in w do
+		  (push (list (plus x half) y) result)
+		  (push (list x (plus y half)) result))
+        finally (return  (if (equal half 1)
+			     (nreverse result)
+			   (munch-compute half (times 2 n)
+					  (nreverse result))))))
+
+(defun munch-draw (pixel list)
+  (loop for (x y) in list do
+	(cursorpos y (times 2 x))
+	(tyo (car pixel))
+	(tyo (cdr pixel))))
+
+(defun munching-squares ()
+  (let ((list (munch-compute 16. 1 '((0 0))))
+        (pixels (list '(#/[ . #/]) '(#\Space. #\Space) nil)))
+    (setf (cdr (cdr pixels)) pixels)
+    (loop
+      (munch-draw (car pixels) list)
+      (setq pixels (cdr pixels)))))