49 lines
No EOL
1.2 KiB
GLSL
49 lines
No EOL
1.2 KiB
GLSL
#version 300 es
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precision mediump float;
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const float inf = 1000000.0;
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const float pi = atan(1.0) * 4.0;
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float interpolate(float from, float to, float quotient) {
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float steppedQ = sin(quotient * pi - pi * 0.5) * 0.5 + 0.5;
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return from + (to - from) * clamp(steppedQ, 0.0, 1.0);
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}
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float noise(float x){
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return fract(sin(x) * 43758.5453123);
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}
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float terrain(float x) {
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float result = 0.0;
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float frequency = 0.01;
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float amplitude = 1.0;
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for (int i = 0; i < 8; i++) {
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result += sin(2.0 * pi * x * frequency - 2.0 * pi * noise(float(i) * 200.0)) * amplitude;
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frequency *= 1.5;
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amplitude /= 1.2;
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}
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return result;
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}
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vec2 random2(vec2 st){
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st = vec2( dot(st,vec2(127.1,311.7)),
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dot(st,vec2(269.5,183.3)) );
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return -1.0 + 2.0*fract(sin(st)*43758.5453123);
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}
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float noise(vec2 st) {
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vec2 i = floor(st);
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vec2 f = fract(st);
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vec2 u = f*f*(3.0-2.0*f);
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return mix( mix( dot( random2(i + vec2(0.0,0.0) ), f - vec2(0.0,0.0) ),
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dot( random2(i + vec2(1.0,0.0) ), f - vec2(1.0,0.0) ), u.x),
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mix( dot( random2(i + vec2(0.0,1.0) ), f - vec2(0.0,1.0) ),
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dot( random2(i + vec2(1.0,1.0) ), f - vec2(1.0,1.0) ), u.x), u.y);
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} |