Shader test bench

Fast Shader

suboptimal-shader-tutorials pattern glsl runnable fragment MIT

runnable fragment

Complete GLSL fragment shader. Stronghold runs it directly when the browser can compile it.

Code

precision mediump float;

uniform float u_time;
uniform vec2 u_resolution;

void main() {
  vec3 black = vec3(0.0);
  vec3 white = vec3(1.0);
  vec3 color = black;

  vec2 uv = 2.0 * gl_FragCoord.xy / u_resolution - 1.0;
  uv.x = uv.x * u_resolution.x / u_resolution.y;
  color = vec3(uv, 0.0);

  float boardSize = 4.0;
  uv = uv * boardSize;
  color = vec3(uv, 0.0);

  vec2 gridUv = fract(uv);
  vec2 gridId = floor(uv);
  color = vec3(gridUv, 0.0);
  color = vec3(gridId, 0.0);
  color = vec3(gridId * 0.2, 0.0);

  if (mod(gridId.x + gridId.y, 2.0) <= 0.01) {
    color = white;
  } else {
    color = black;
  }

  gl_FragColor = vec4(color, 1.0);
}

Code

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