mirror of
https://github.com/patriciogonzalezvivo/thebookofshaders
synced 2024-11-08 01:10:27 +00:00
28 lines
596 B
GLSL
28 lines
596 B
GLSL
// 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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uniform vec2 u_resolution;
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uniform float u_time;
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float rect(in vec2 _st, in vec2 _size){
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_size = vec2(0.5) - _size*0.5;
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vec2 uv = smoothstep(_size,
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_size+vec2(0.001),
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_st);
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uv *= smoothstep(_size,
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_size+vec2(0.001),
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vec2(1.0)-_st);
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return uv.x*uv.y;
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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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vec3 color = vec3( rect(st, vec2(0.9)) );
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gl_FragColor = vec4(color,1.0);
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} |