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• glsl
  #ifdef GL_ES
  precision mediump float;
  #endif
  
  uniform float time;
  uniform vec2 mouse;
  uniform vec2 resolution;
  
  float rayIntersect(vec2 cOrigin, float cRadius, vec2 rStart, vec2 rEnd)
  {
  vec2 cOrigNew = cOrigin - rStart;
  
  vec2 rDir = normalize(rEnd - rStart);
  
  float b = dot(cOrigNew, rDir);
  float c = cRadius * cRadius - dot(cOrigNew, cOrigNew);
  float a = dot(rDir, rDir);
  
  float invA = 1.0 / a;
  
  if((b * b + a * c) <= 0.0)
  return 0.0;
  
  float b4ac = sqrt(b*b + a * c);
  
  float l1 = (b - b4ac) * invA;
  float l2 = (b + b4ac) * invA;
  
  return l2 < 0.0 || dot(rDir, cOrigin - rEnd) > 0.0 ? 0.0 : pow(l2, 0.1);
  
  return 1.0;
  
  return 0.0;
  }
  
  void main( void ) {
  
  vec2 position = ( gl_FragCoord.xy / resolution.xy );
  
  float color = 1.0;
  
  color *= 1.0 - rayIntersect(vec2(0.25, 0.25), 0.05, mouse, position);
  color *= 1.0 - rayIntersect(vec2(0.5, 0.25), 0.05, mouse, position);
  color *= 1.0 - rayIntersect(vec2(0.75, 0.25), 0.05, mouse, position);
  
  color *= 1.0 - rayIntersect(vec2(0.25, 0.5), 0.05, mouse, position);
  color *= 1.0 - rayIntersect(vec2(0.5, 0.5), 0.05, mouse, position);
  color *= 1.0 - rayIntersect(vec2(0.75, 0.5), 0.05, mouse, position);
  
  
  color *= 1.0 - rayIntersect(vec2(0.25, 0.75), 0.05, mouse, position);
  color *= 1.0 - rayIntersect(vec2(0.5, 0.75), 0.05, mouse, position);
  color *= 1.0 - rayIntersect(vec2(0.75, 0.75), 0.05, mouse, position);
  
  gl_FragColor = vec4(color, color, color, 9.0 );
  
  }
  

  • glsl
  # 4943 days ago quilime