blob: e824f76edda1b81fd64aa786d7035786029ba75b [file] [log] [blame]
John Kessenichf6eae2a2016-01-22 17:47:22 -07001#version 140
2in vec2 tex_coord;
John Kessenich39374da2015-05-15 21:32:46 +00003
4void main (void)
5{
6 vec4 white = vec4(1.0);
7 vec4 black = vec4(0.2);
8 vec4 color = white;
9
10 // First, cut out our circle
11 float x = tex_coord.x*2.0 - 1.0;
12 float y = tex_coord.y*2.0 - 1.0;
13
14 float radius = sqrt(x*x + y*y);
15 if (radius > 1.0) {
16 if (radius > 1.1) {
17 ++color;
18 }
19
20 gl_FragColor = color;
21
22 if (radius > 1.2) {
23 ++color;
24 }
25
26 discard;
27 }
28
29 // If we're near an edge, darken us a tiny bit
30 if (radius >= 0.75)
31 color -= abs(pow(radius, 16.0)/2.0);
32
33 gl_FragColor = color;
34
35}