src/shaders/rect_vert.glsl

   1 #version 140
   2 #extension GL_ARB_shading_language_420pack : require
   3 #extension GL_ARB_explicit_attrib_location : require
   4
   5 layout(std140, binding=0) uniform ViewBounds
   6 {
   7         float bounds_x;
   8         float bounds_y;
   9         float bounds_w;
  10         float bounds_h;
  11         float pixel_x;
  12         float pixel_y;
  13         float pixel_w;
  14         float pixel_h;
  15 };
  16
  17 layout(location = 0) in vec2 position;
  18
  19 out int objectid;
  20 out vec2 pixsize;
  21
  22 void main()
  23 {
  24         vec2 transformed_position;
  25         transformed_position.x = (position.x - bounds_x) / bounds_w;
  26         transformed_position.y = (position.y - bounds_y) / bounds_h;
  27         // Transform to clip coordinates (-1,1, -1,1).
  28         gl_Position.x = (transformed_position.x*2) - 1;
  29         gl_Position.y = 1 - (transformed_position.y*2);
  30         gl_Position.z = 0.0;
  31         gl_Position.w = 1.0;
  32         pixsize = vec2(pixel_w/bounds_w, 100*pixel_h/bounds_h);
  33         objectid = gl_VertexID / 2;
  34 }