36 lines
666 B
GLSL
36 lines
666 B
GLSL
#version 110
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varying vec2 tex_coord;
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void main (void)
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{
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vec4 white = vec4(1.0);
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vec4 black = vec4(0.2);
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vec4 color = white;
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// First, cut out our circle
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float x = tex_coord.x*2.0 - 1.0;
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float y = tex_coord.y*2.0 - 1.0;
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float radius = sqrt(x*x + y*y);
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if (radius > 1.0) {
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if (radius > 1.1) {
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++color;
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}
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gl_FragColor = color;
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if (radius > 1.2) {
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++color;
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}
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discard;
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}
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// If we're near an edge, darken us a tiny bit
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if (radius >= 0.75)
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color -= abs(pow(radius, 16.0)/2.0);
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gl_FragColor = color;
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}
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