Make optimizer registration fail if a canvas has already been written

to.

1 files changed, 11 insertions, 2 deletions

diff --git a/libdimension/canvas.c b/libdimension/canvas.c
index d53c7ef..4151a0b 100644
--- a/libdimension/canvas.c
+++ b/libdimension/canvas.c
@@ -43,6 +43,7 @@ dmnsn_new_canvas(unsigned int x, unsigned int y)
 
     /* Allocate room for the optimizers */
     canvas->optimizers = dmnsn_new_array(sizeof(dmnsn_canvas_optimizer));
+    canvas->too_late = 0;
   }
 
   return canvas;
@@ -71,10 +72,15 @@ dmnsn_delete_canvas(dmnsn_canvas *canvas)
 }
 
 /* Set a canvas optimizer */
-void
+int
 dmnsn_optimize_canvas(dmnsn_canvas *canvas, dmnsn_canvas_optimizer optimizer)
 {
-  dmnsn_array_push(canvas->optimizers, &optimizer);
+  if (canvas->too_late) {
+    return 1;
+  } else {
+    dmnsn_array_push(canvas->optimizers, &optimizer);
+    return 0;
+  }
 }
 
 /* Set the color of a pixel */
@@ -85,6 +91,9 @@ dmnsn_set_pixel(dmnsn_canvas *canvas, unsigned int x, unsigned int y,
   unsigned int i;
   dmnsn_canvas_optimizer optimizer;
 
+  /* Don't allow any more optimizers */
+  canvas->too_late = 1;
+
   /* Set the pixel */
   canvas->pixels[y*canvas->x + x] = color;