Lucas de Vries
30 lines
745 B
Plaintext
30 lines
745 B
Plaintext
#define pi 3.141592653589793238462643383279
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#define twopi (pi * 2.0)
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uniform float dist;
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uniform float scale;
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uniform float minRad;
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uniform float maxRad;
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varying vec2 rcoords;
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void main() {
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float modDist = dist / scale;
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float width = 0.02 * max(min(modDist / 10.0, 5.0), 1.0);
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float r = length(rcoords);
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if(r >= 1.0 || r < 1.0 - width)
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discard;
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float ang = atan(rcoords.y, rcoords.x);
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if(ang < minRad && ang > maxRad - twopi)
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discard;
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if(ang > maxRad && ang < minRad + twopi)
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discard;
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float bdist = r - (1.0 - width);
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vec4 col = gl_Color;
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col.a = 0.5;
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col.a *= min(bdist / (width * 0.5), (width - bdist) / (width * 0.5));
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col.a *= 1.0 - smoothstep(30.0, 70.0, modDist);
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gl_FragColor = col;
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}
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