mirror of
https://github.com/patriciogonzalezvivo/thebookofshaders
synced 2024-11-17 21:25:40 +00:00
50 lines
980 B
GLSL
50 lines
980 B
GLSL
// Author @patriciogv ( patriciogonzalezvivo.com ) - 2015
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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 3.14159265358979323846
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uniform vec2 u_resolution;
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uniform float u_time;
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float rows = 10.0;
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vec2 brickTile(vec2 _st, float _zoom){
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_st *= _zoom;
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if (fract(_st.y * 0.5) > 0.5){
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_st.x += 0.5;
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}
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return fract(_st);
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}
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vec2 rotate2D(vec2 _st, float _angle){
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_st -= 0.5;
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_st = mat2(cos(_angle),-sin(_angle),
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sin(_angle),cos(_angle)) * _st;
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_st += 0.5;
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return _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 = brickTile(st,rows);
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float angle = PI*0.25*cos(u_time*0.5);
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if (fract( (gl_FragCoord.y/u_resolution.y) * 0.5 * rows) > 0.5){
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angle *= -1.0;
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}
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st = rotate2D(st,angle);
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st *= 2.0;
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float pct = (1.0+cos(PI*st.x))*0.5;
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vec3 color = vec3( 1.0-smoothstep( 0.5,0.6, pow(pct,st.y) ) * 1.0-smoothstep( 0.79,0.81, pow(pct,2.0-st.y ) ) );
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gl_FragColor = vec4(color,1.0);
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}
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