1 2layout (location = 1) noperspective out vec2 vcoord_Stage0; 3void main() { 4 int x = gl_InstanceID % 200; 5 int y = gl_InstanceID / 200; 6 int ileft = (gl_InstanceID * 929) % 17; 7 int iright = (ileft + 1) + (gl_InstanceID * 1637) % (17 - ileft); 8 int itop = (gl_InstanceID * 313) % 17; 9 int ibot = (itop + 1) + (gl_InstanceID * 1901) % (17 - itop); 10 float outset = 0.03125; 11 outset = 0 == (x + y) % 2 ? -outset : outset; 12 float l = float(ileft) * 0.0625 - outset; 13 float r = float(iright) * 0.0625 + outset; 14 float t = float(itop) * 0.0625 - outset; 15 float b = float(ibot) * 0.0625 + outset; 16 vec2 vertexpos; 17 vertexpos.x = float(x) + (0 == gl_VertexID % 2 ? l : r); 18 vertexpos.y = float(y) + (0 == gl_VertexID / 2 ? t : b); 19 vcoord_Stage0.x = float(0 == gl_VertexID % 2 ? -1 : 1); 20 vcoord_Stage0.y = float(0 == gl_VertexID / 2 ? -1 : 1); 21 gl_Position = vec4(vertexpos.x, vertexpos.y, 0.0, 1.0); 22} 23