|
|
|
@ -0,0 +1,34 @@
|
|
|
|
|
// Yosuke SAKAI(@flush_11, http://yosuke-sakai.com/)
|
|
|
|
|
// Drawing multiple shaping functions on gradient background
|
|
|
|
|
// A sample for the book of the shaders.
|
|
|
|
|
// http://thebookofshaders.com/05/
|
|
|
|
|
|
|
|
|
|
#ifdef GL_ES
|
|
|
|
|
precision mediump float;
|
|
|
|
|
#endif
|
|
|
|
|
|
|
|
|
|
uniform vec2 u_resolution;
|
|
|
|
|
uniform vec2 u_mouse;
|
|
|
|
|
uniform float u_time;
|
|
|
|
|
|
|
|
|
|
// Plot a line on Y using a value between 0.0-1.0
|
|
|
|
|
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;
|
|
|
|
|
|
|
|
|
|
//backgoud gradient
|
|
|
|
|
vec3 bkcolor = vec3(st.x);
|
|
|
|
|
|
|
|
|
|
// Plot a lines
|
|
|
|
|
float pct1 = plot(st,st.x);
|
|
|
|
|
float pct2 = plot(st,pow(st.x, 0.5));
|
|
|
|
|
float pct3 = plot(st, pow(st.x, 2.0));
|
|
|
|
|
|
|
|
|
|
vec3 color = (1.0-pct1)*(1.0-pct2)*(1.0-pct3)*bkcolor+pct1*vec3(1.0,0.0,0.0)+pct2*vec3(0.0,1.0,0.0) + pct3*vec3(0.0, 1.0, 1.0);
|
|
|
|
|
|
|
|
|
|
gl_FragColor = vec4(color,1.0);
|
|
|
|
|
}
|