Ch. 16: Allow smaller canvas for smaller level

Author: jobo3208

16_canvas.txt

@@ -835,8 +835,8 @@ standing still, it keeps facing the direction it last moved in.
 ----
 function CanvasDisplay(parent, level) {
   this.canvas = document.createElement("canvas");
-  this.canvas.width = 600;
-  this.canvas.height = 450;
+  this.canvas.width = Math.min(600, level.width * scale);
+  this.canvas.height = Math.min(450, level.height * scale);
   parent.appendChild(this.canvas);
   this.cx = this.canvas.getContext("2d");