29 lines
611 B
HLSL
29 lines
611 B
HLSL
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#ifndef UNITY_SDF2D_INCLUDED
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#define UNITY_SDF2D_INCLUDED
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// Ref: https://www.iquilezles.org/www/articles/distfunctions2d/distfunctions2d.htm
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float CircleSDF(float2 position, float radius)
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{
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return length(position) - radius;
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}
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float RectangleSDF(float2 position, float2 bound)
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{
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float2 d = abs(position) - bound;
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return length(max(d, float2(0, 0))) + min(max(d.x, d.y), 0.0);
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}
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float EllipseSDF(float2 position, float2 r)
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{
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float2 p = position;
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float2 r2 = r*r;
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float k0 = length(p/r);
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float k1 = length(p/r2);
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return k0*(k0 - 1.0)/k1;
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}
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#endif // UNITY_SDF2D_INCLUDED
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