Add perspective projection.

git-svn-id: svn://svn.mplayerhq.hu/mplayer/trunk@23032 b3059339-0415-0410-9bf9-f77b7e298cf2
This commit is contained in:
eugeni 2007-04-20 22:56:42 +00:00
parent cf9aff424f
commit 36870a2a52
1 changed files with 12 additions and 0 deletions

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@ -1589,6 +1589,18 @@ static inline void transform_vector_3d(FT_Vector* v, double *m) {
a[2] = 0.;
a[3] = 1.;
transform_point_3d(a, m, b);
/* Apply perspective projection with the following matrix:
2500 0 0 0
0 2500 0 0
0 0 0 0
0 0 8 2500
where 2500 is camera distance, 8 - z-axis scale.
Camera is always located in (org_x, org_y, -2500). This means
that different subtitle events can be displayed at the same time
using different cameras. */
b[0] *= 2500;
b[1] *= 2500;
b[3] = 8 * b[2] + 2500;
if (b[3] < 0.001 && b[3] > -0.001)
b[3] = b[3] < 0. ? -0.001 : 0.001;
v->x = double_to_d6(b[0] / b[3]);