第 4 课：Relative Luminance

我的解：Relative Luminance 是根据人类视觉能感受的光谱总结出来的formula

我的解

uniform vec2 iResolution;
uniform sampler2D iChannel0;

vec3 RelativeLuminance(vec3 tex){
  return vec3(tex.r * 0.2126 + tex.g * 0.7152 + tex.b * 0.0722);
}

void main() {
  // Normalized pixel coordinates (from 0 to 1)
  vec2 uv = gl_FragCoord.xy / iResolution.xy;
  vec4 tex = texture(iChannel0, uv);

  gl_FragColor = vec4(RelativeLuminance(tex.rgb), 1.0);
}

复盘笔记

• Relative Luminance 是根据人类视觉能感受的光谱总结出来的formula
• L = R * 0.2126 + G * 0.7152 + B * 0.0722;