mirror of
https://github.com/patriciogonzalezvivo/thebookofshaders
synced 2024-11-08 01:10:27 +00:00
31 lines
660 B
GLSL
31 lines
660 B
GLSL
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// Author @patriciogv - 2015
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// http://patriciogonzalezvivo.com
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#ifdef GL_ES
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precision mediump float;
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#endif
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#define PI 3.14159265359
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#define TWO_PI 6.28318530718
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uniform vec2 u_resolution;
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uniform vec2 u_mouse;
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uniform float u_time;
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float shape(vec2 st, int N){
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st = st *2.-1.;
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float a = atan(st.x,st.y)+PI;
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float r = TWO_PI/float(N);
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return cos(floor(.5+a/r)*r-a)*length(st);
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}
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void main(){
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vec2 st = gl_FragCoord.xy/u_resolution.xy;
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st.x *= u_resolution.x/u_resolution.y;
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vec3 color = vec3(0.0);
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float d = 0.0;
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d = min(shape(st,3),shape(st+vec2(0.,0.2),4));
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gl_FragColor = vec4(vec3(1.0-smoothstep(.2,.25,d)),1.0);
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}
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