Garbled rendering of transformed content

[jrmuizel]

http://people.mozilla.org/~jmuizelaar/servo/clipped-rotate.html renders badly on OS X

[glennw]

#431 fixes the text being garbled. However, we need to add support for transformed clip rects to close this bug completely - I'll try to work on that in the next week or two.

[kvark]

Looking into this...

[kvark]

[kvark]

Interestingly, if I disable the WR_FEATURE_TRANSFORM paths in the text_run shaders, it renders better:

The layout seems to differ a bit with Firefox, and the font is smaller. Also, there are thin lines visible on the tile boundaries (I assume).

[kvark]

Got it almost fixed now with WR_FEATURE_TRANSFORM:

There is some stuff missing at the end of the lines, not sure if because of rendering or not. Will investigate and file a PR for what I got regardless.