webgl函数 clamp_webgl clamp

一、简介

参考资料：The Book of Shaders: clamp
clamp函数将一个值限制在另外两个值之间

y = clamp(x,0.0,1.0); 

二、代码

#ifdef GL_ES
precision mediump float;
#endif
 
uniform vec2 u_resolution;
uniform vec2 u_mouse;
uniform float u_time;
 
void main() {
    vec2 st = gl_FragCoord.xy/u_resolution;
    vec4 color1=vec4(0.0,0.0,0.0,1.0);
//    color1.r=clamp(st.s,0.0,1.0);
    color1.g=clamp(st.s,0.0,1.0);
    color1.r=clamp(st.s,0.0,1.0);
    gl_FragColor = color1;
}

三、效果