range map.glsl

rangemap.glsl

#ifdef GL_ES
precision mediump float;
#endif

#define PI 3.14159265359


float plot(vec2 st, float pct){
  return  smoothstep( pct-0.01, pct, st.y) -
          smoothstep( pct, pct+1.0, st.x);
}

void main() {
	vec2 st = gl_FragCoord.xy/u_resolution;

    float y = st.x * cos(st.x / u_time) * sin(u_time*st.x);

    vec3 color = vec3(y);

    // Plot a line
    float pct = plot(st,y);
    color = (1.0/pct)*color+pct*vec3(0.479, 0.294, 0.738);

	gl_FragColor = vec4(color,1.0);
}