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1d-noise.frag
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1d-noise.frag
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// Author @patriciogv - 2015
// http://patriciogonzalezvivo.com
#ifdef GL_ES
precision mediump float;
#endif
uniform vec2 u_resolution;
uniform vec2 u_mouse;
uniform float u_time;
float plot(vec2 st, float pct){
return smoothstep( pct-0.01, pct, st.y) -
smoothstep( pct, pct+0.01, st.y);
}
float random (in float x) {
return fract(sin(x)*1e4);
}
float noise (in float x) {
float i = floor(x);
float f = fract(x);
// Cubic Hermine Curve
float u = f * f * (3.0 - 2.0 * f);
return mix(random(i), random(i + 1.0), u);
}
void main() {
vec2 st = gl_FragCoord.xy/u_resolution.xy;
st.x *= u_resolution.x/u_resolution.y;
vec3 color = vec3(0.0);
float y = 0.0;
// y = random(st.x*0.001+u_time);
y = noise(st.x*3.+u_time);
// color = vec3(y);
float pct = plot(st,y);
color = (1.0-pct)*color+pct*vec3(0.0,1.0,0.0);
gl_FragColor = vec4(color,1.0);
}