第 7 课：Dot - Classify

我的解

uniform float iTime;
uniform vec2 iResolution;

void main() {
  vec2 uv = gl_FragCoord.xy / iResolution.xy;
  uv *= 2.0;
  uv -= 1.0;
  uv.x *= iResolution.x / iResolution.y;

  vec2 a = vec2(0.0, 0.0);
  vec2 b = vec2(cos(iTime), sin(iTime));
  float dotResult = dot(uv, b);

  vec3 result = mix(vec3(0.12), vec3(1.0, 0.3, 0.3), dotResult);

  gl_FragColor = vec4(result, 1.0);
}