Static p5_sys::global::createShader

pub static createShader: CreateShaderInternalType

No description available

Examples

// the 'varying's are shared between both vertex & fragment shaders
let varying = 'precision highp float; varying vec2 vPos;';

// the vertex shader is called for each vertex
let vs =
  varying +
  'attribute vec3 aPosition;' +
  'void main() { vPos = (gl_Position = vec4(aPosition,1.0)).xy; }';

// the fragment shader is called for each pixel
let fs =
  varying +
  'uniform vec2 p;' +
  'uniform float r;' +
  'const int I = 500;' +
  'void main() {' +
  '  vec2 c = p + vPos * r, z = c;' +
  '  float n = 0.0;' +
  '  for (int i = I; i > 0; i --) {' +
  '    if(z.x*z.x+z.y*z.y > 4.0) {' +
  '      n = float(i)/float(I);' +
  '      break;' +
  '    }' +
  '    z = vec2(z.x*z.x-z.y*z.y, 2.0*z.x*z.y) + c;' +
  '  }' +
  '  gl_FragColor = vec4(0.5-cos(n*17.0)/2.0,0.5-cos(n*13.0)/2.0,0.5-cos(n*23.0)/2.0,1.0);' +
  '}';

let mandel;
function setup() {
  createCanvas(100, 100, WEBGL);

  // create and initialize the shader
  mandel = createShader(vs, fs);
  shader(mandel);
  noStroke();

  // 'p' is the center point of the Mandelbrot image
  mandel.setUniform('p', [-0.74364388703, 0.13182590421]);
}

function draw() {
  // 'r' is the size of the image in Mandelbrot-space
  mandel.setUniform('r', 1.5 * exp(-6.5 * (1 + sin(millis() / 2000))));
  quad(-1, -1, 1, -1, 1, 1, -1, 1);
}

Parameters

vertSrc source code for the vertex shader

fragSrc source code for the fragment shader