From: eugeni <eugeni@b3059339-0415-0410-9bf9-f77b7e298cf2>
Date: Fri, 22 Feb 2008 19:31:49 +0000 (+0000)
Subject: Better handling of behind-the-camera objects.
X-Git-Tag: 0.9.7~225
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=cefaf08c831bb1acdda55b7d38192fac3ead6d59;p=libass

Better handling of behind-the-camera objects.

Every point that is behind the camera is moved to the clipping plane by
orthographic projection. It is obviously incorrect, but this is a very rare
case, and proper clipping of Bezier curves is not that easy.


git-svn-id: svn://svn.mplayerhq.hu/mplayer/trunk@26065 b3059339-0415-0410-9bf9-f77b7e298cf2
---

diff --git a/libass/ass_render.c b/libass/ass_render.c
index 6b345a7..0565729 100644
--- a/libass/ass_render.c
+++ b/libass/ass_render.c
@@ -1623,6 +1623,7 @@ static inline void transform_point_3d(double *a, double *m, double *b)
  */
 static inline void transform_vector_3d(FT_Vector* v, double *m) {
 	const double camera = 2500 * frame_context.border_scale; // camera distance
+	const double cutoff_z = 10.;
 	double a[4], b[4];
 	a[0] = d6_to_double(v->x);
 	a[1] = d6_to_double(v->y);
@@ -1641,8 +1642,8 @@ static inline void transform_vector_3d(FT_Vector* v, double *m) {
 	b[0] *= camera;
 	b[1] *= camera;
 	b[3] = 8 * b[2] + camera;
-	if (b[3] < 0.001 && b[3] > -0.001)
-		b[3] = b[3] < 0. ? -0.001 : 0.001;
+	if (b[3] < cutoff_z)
+		b[3] = cutoff_z;
 	v->x = double_to_d6(b[0] / b[3]);
 	v->y = double_to_d6(b[1] / b[3]);
 }