Two fixes in one commit.

- The ortho render recode had a weak method to calculate the Z value of the
  render coordinate (shi.co[2]). Worked OK for normal render, but not in
  unified, giving big errors in Ortho Unfied render.
  Solved with proper math, using face equation a*x+b*y+c*y=d. Dunno why I
  didn't do it in first place. :)

- Bug fix #2493. Edge render gave much different result for Ortho. This
  was due to overflows in the integer math filtering zbuffer values.
  Cleaned it op properly, preventing any integer overflow now.

1 files changed, 1 insertions, 0 deletions

diff --git a/source/blender/render/intern/include/rendercore.h b/source/blender/render/intern/include/rendercore.h
index 158977cef5a..5163b85d8c0 100644
--- a/source/blender/render/intern/include/rendercore.h
+++ b/source/blender/render/intern/include/rendercore.h
@@ -70,6 +70,7 @@ typedef struct PixStrMain
 } PixStrMain;
 
 
+void	calc_view_vector(float *view, float x, float y);
 float   mistfactor(float zcor, float *co);	/* dist and height, return alpha */
 
 void	add_halo_flare(void);