bezier.geom revision 32001f49 
1#version 120
2#extension GL_EXT_geometry_shader4: enable
3
4uniform int NumSubdivisions;
5
6void main()
7{
8   /* num is the number of subdivisions
9    * can be anything between 1 and infinity
10    */
11   int num = NumSubdivisions;
12
13   float dt = 1. / float(num);
14   float t = 0.;
15   for (int i = 0; i <= num; i++) {
16      float omt = 1. - t;
17      float omt2 = omt * omt;
18      float omt3 = omt * omt2;
19      float t2 = t * t;
20      float t3 = t * t2;
21      vec4 xyzw =
22         omt3 * gl_PositionIn[0].xyzw +
23         3. * t * omt2 * gl_PositionIn[1].xyzw +
24         3. * t2 * omt * gl_PositionIn[2].xyzw +
25         t3 * gl_PositionIn[3].xyzw;
26      gl_Position = xyzw;
27      gl_FrontColor = vec4(1, 1, 1, 1);
28      EmitVertex();
29      t += dt;
30   }
31}
32