thebookofshaders/05/smoothstep.frag
2017-08-23 11:34:44 +02:00

29 lines
561 B
GLSL

#ifdef GL_ES
precision mediump float;
#endif
#define PI 3.14159265359
uniform vec2 u_resolution;
uniform vec2 u_mouse;
uniform float u_time;
float plot(vec2 st, float pct){
return smoothstep( pct-0.02, pct, st.y) -
smoothstep( pct, pct+0.02, st.y);
}
void main() {
vec2 st = gl_FragCoord.xy/u_resolution;
// Smooth interpolation between 0.1 and 0.9
float y = smoothstep(0.1,0.9,st.x);
vec3 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);
}