1
2/* Infinite grid
3 * Clément Foucault */
4
5uniform vec3 planeAxes;
6uniform vec3 gridSize;
7
8uniform int gridFlag;
9
10#define PLANE_XY (1 << 4)
11#define PLANE_XZ (1 << 5)
12#define PLANE_YZ (1 << 6)
13#define CLIP_Z_POS (1 << 7)
14#define CLIP_Z_NEG (1 << 8)
15#define PLANE_IMAGE (1 << 11)
16in vec3 pos;
17
18out vec3 local_pos;
19
20void main()
21{
22  vec3 vert_pos;
23
24  /* Project camera pos to the needed plane */
25  if ((gridFlag & PLANE_XY) != 0) {
26    vert_pos = vec3(pos.x, pos.y, 0.0);
27  }
28  else if ((gridFlag & PLANE_XZ) != 0) {
29    vert_pos = vec3(pos.x, 0.0, pos.y);
30  }
31  else if ((gridFlag & PLANE_YZ) != 0) {
32    vert_pos = vec3(0.0, pos.x, pos.y);
33  }
34  else /* PLANE_IMAGE */ {
35    vert_pos = vec3(pos.xy * 0.5 + 0.5, 0.0);
36  }
37
38  local_pos = vert_pos;
39
40  vec3 real_pos = cameraPos * planeAxes + vert_pos * gridSize;
41
42  /* Used for additional Z axis */
43  if ((gridFlag & CLIP_Z_POS) != 0) {
44    real_pos.z = clamp(real_pos.z, 0.0, 1e30);
45    local_pos.z = clamp(local_pos.z, 0.0, 1.0);
46  }
47  if ((gridFlag & CLIP_Z_NEG) != 0) {
48    real_pos.z = clamp(real_pos.z, -1e30, 0.0);
49    local_pos.z = clamp(local_pos.z, -1.0, 0.0);
50  }
51
52  gl_Position = ViewProjectionMatrix * vec4(real_pos, 1.0);
53}
54