When tiles have overlap, rendering cropped tiles could throw an error.
This happened on IE11.  By ensuring we don't ask to crop to a size
larger than the image, it works properly.
MODIFY
src/canvas/quadFeature.js
src/canvas/quadFeature.js
@@ -174,8 +174,11 @@ var canvas_quadFeature = function (arg) {
if (!quad.crop) {
context2d.drawImage(src, 0, 0);
} else {
- context2d.drawImage(src, 0, 0, quad.crop.x, quad.crop.y, 0, 0,
- quad.crop.x, quad.crop.y);
+ var cropx = Math.min(src.w, quad.crop.x),
+ cropy = Math.min(src.h, quad.crop.y);
+ if (cropx > 0 && cropy > 0) {
+ context2d.drawImage(src, 0, 0, cropx, cropy, 0, 0, cropx, cropy);
+ }
}
});
});

When tiles have overlap, rendering cropped tiles could throw an error.

This happened on IE11.  By ensuring we don't ask to crop to a size
larger than the image, it works properly.