CropDemo control weirdness

[davidmw]

I'm exploring the unmodified CropDemo on an iPhone5 and am having difficulty controlling the crop rectangle.

The net result is that it is quite difficult to set the crop rectangle to the full height or width of the original image.

Often the crop rectangle ends up 1-3 pixels too short or narrow. Once the white crop handles intersect the edge of the photo, they are nearly impossible to move again.

I have the impression that the crop handle 'jumps' to the touch down location - which is annoying when I'm trying to make a very slight change in the rectangle size.

My guess is that the touch outside detection is occasionally getting triggered when I actually want to grab a handle. Either the touch outside or handle touch seems to calculate position based on a touch offset and the math is a bit wrong in some cases, preventing the edge of the crop rectangle from being moved to the precise edge of the photo. I haven't looked at the code enough to figure out why the crop handles then seem to get locked in place.

Also, I'll note that rotating the device to landscape seems to lay a resized copy of the original photo behind the portrait sized photo and shadow mask. The buttons are also not moving like you'd expect.

David