Now the theta = 0 should be on +x axis.
And cos(theta) should correctly represent x value.
Without this fix, the poly theta (from atan2) can be wrongly rotated 90 degrees.
Also, make sure the incoming polygon is CW for the shadow system.
This fix visual artifacts in recent regression for spot shadows.
bug:13553955
Change-Id: I9bbf54db094e7f133326da4dae4610962da849c1
In the current design, this error should be tolerated since the delta should
be small enough. So we should not return here.
Change-Id: I251db2882b331d37ae7f0896e9aa95d69a5650da
Separate matrix passed to shadow system into two parts, one for
transforming the polygon XY points (using the actual draw matrix) and
a separate one which respects correct 4x4 3d rotations and
translations for determining Z values.
Change-Id: I7e30a84774a8709df6b2241e8f51fc5583648fe8
