// water test with vertex colouring
// use mouse to control perlin noise octaves and position in space
// author: info@toxi.co.uk

float yoff,zoff,ns=0.1,zs=8;

void setup() {
  size(512,256);
  noStroke();
}

void loop() {
  float nx,ny=yoff,z1,z2;

  // setup viewport
  background(20,40,50);
  translate(width*0.5,height*.55,0);
  rotateX(PI/3.25);
  scale(15);

  // ripple control
  noiseDetail(8,mouseY*(0.6/height));

// draw surface
  for(int y=-10; y<=10; y++) {
    nx=mouseX*0.005;
    beginShape(TRIANGLE_STRIP);
    for(int x=-25; x<25; x++) {
      z1=noise(nx,ny,zoff);
      z2=noise(nx,ny+ns,zoff);
      fill(0,z1*160,z1*255,pow(10,0.85+z1*2));
      vertex(x,y,z1*zs);
      fill(0,z2*160,z2*255,pow(10,0.85+z2*2));
      vertex(x,y+1,z2*zs);
      nx+=ns;
    }
    endShape();
    ny+=ns;
  }
  // animate waves
  zoff+=0.045;
  yoff-=0.06;
}