+ - Testing
+ - Test implementations against each other
+ - Test both with and without the operator strength reduction.
+ They shold be identical.
+
- SSE 2 issues:
- Use MM_HINT_NTA instead of MM_HINT_T0
the required precision by simply adding offset_x/y to the
relevant rendering API?
+ - Get rid of workaround for X server bug.
+
- pixman_image_set_indexed() should copy its argument, and X
should be ported over to use a pixman_image as the
representation of a Picture, rather than creating one on each