[truetype] Fix phantom point handling.

This is a further improvement to the changes from 2013-11-06.

* src/truetype/ttgload.c (TT_Hint_Glyph): Horizontal phantom points
are rounded horizontally, vertical ones are rounded vertically.
(TT_LOADER_SET_PP): The horizontal position of vertical phantom
points in pre-ClearType mode is zero, as shown in the OpenType
specification.
2 files changed