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 };
  12
  13 layout(location = 0) in vec2 position;
  14
  15 out int objectid;
  16
  17 void main()
  18 {
  19         vec2 transformed_position;
  20         transformed_position.x = (position.x - bounds_x) / bounds_w;
  21         transformed_position.y = (position.y - bounds_y) / bounds_h;
  22         // Transform to clip coordinates (-1,1, -1,1).
  23         gl_Position.x = (transformed_position.x*2) - 1;
  24         gl_Position.y = 1 - (transformed_position.y*2);
  25         gl_Position.z = 0.0;
  26         gl_Position.w = 1.0;
  27
  28         objectid = gl_VertexID / 2;
  29 }