From 4b03ea2a9c8b66bad704e9cef026801786aa3517 Mon Sep 17 00:00:00 2001 From: Matthias Schiffer Date: Tue, 2 Feb 2016 05:35:00 +0100 Subject: Add two more examples --- examples/symmetry.frag | 41 +++++++++++++++++++++++++++++++++++++++++ 1 file changed, 41 insertions(+) create mode 100644 examples/symmetry.frag (limited to 'examples/symmetry.frag') diff --git a/examples/symmetry.frag b/examples/symmetry.frag new file mode 100644 index 0000000..0fb9cd1 --- /dev/null +++ b/examples/symmetry.frag @@ -0,0 +1,41 @@ +#version 330 + +out vec4 fragColor; + +uniform vec2 res; +uniform float time; + +const float sharpness = 300; + +const float PI = 3.14159265358979323846; + + +mat2 rot(float a) { + return mat2( + cos(a), -sin(a), + sin(a), cos(a) + ); +} + +float square(vec2 m, float a, float r, vec2 p) { + vec2 diff = abs((m - p) * rot(r)); + float d = max(diff.x, diff.y); + + return clamp((a - d)*sharpness, 0.0, 1.0); +} + +void main(void) { + vec2 m = res/2; + float s = min(m.x, m.y); + vec2 p = (gl_FragCoord.xy - m) / s; + + float scene = 0; + + int n = 24; + for (int i = 0; i < n; i++) { + float c = square(vec2(0.5, 0) * rot(PI/2*(4.0*i/n)) * vec2(1, 1), 0.3, PI/2*(24.0*i/n - time/800), p); + scene = abs(scene - c); + } + + fragColor = vec4(vec3(1, 1, 1) * scene, 1); +} -- cgit v1.2.3