shader 案例学习笔记之step函数

step函数

        step(edge,x)：当x>edge时返回1，否则返回0

#ifdef GL_ES
precision mediump float;
#endifuniform vec2 u_resolution;void main(){vec2 st = gl_FragCoord.xy/u_resolution.xy;float f = step(0.5, st.x);gl_FragColor = vec4(f, 0, 0, 1.0); 
}

 类似下面的javaScript代码

float myStep(float edge, float x){if(x>= edge){return 1.0;}else{return 0.0;}
}