28 lines
729 B
GLSL
28 lines
729 B
GLSL
const float PI = 3.1415926535;
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uniform vec2 resolution;
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uniform float amount;
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uniform float xoff;
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uniform float yoff;
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vec2 distort(vec2 p, vec2 offset) {
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float theta = atan(p.y, p.x);
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float radius = length(p);
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radius = pow(radius, (1.0+amount*0.01));
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p.x = radius * cos(theta) + offset.x;
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p.y = radius * sin(theta) + offset.y;
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return 0.5 * (p + 1.0);
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}
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vec4 process(vec4 col) {
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vec2 offset = vec2(xoff/resolution.x, yoff/resolution.y);
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vec2 xy = 2.0 * v_texcoord - 1.0 - offset;
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vec2 uv;
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float d = length(xy);
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uv = distort(xy, offset);
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if (uv.x >= 0.0 && uv.x <= 1.0 && uv.y >= 0.0 && uv.y <= 1.0) {
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return texture2D(texture, uv);
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} else {
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return vec4(0.0);
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}
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} |