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cmyk knot
int[][] result;
float t, c;
float ease(float p) {
return 3*p*p - 2*p*p*p;
}
float ease(float p, float g) {
if (p < 0.5)
return 0.5 * pow(2*p, g);
else
return 1 - 0.5 * pow(2*(1 - p), g);
}
float mn = .5*sqrt(3), ia = atan(sqrt(.5));
void push() {
pushMatrix();
pushStyle();
}
void pop(){
popStyle();
popMatrix();
}
void draw() {
if(!recording){
t = mouseX*1.0/width;
c = mouseY*1.0/height;
if(mousePressed)
println(c);
draw_();
}
else {
for (int i=0; i<width*height; i++)
for (int a=0; a<3; a++)
result[i][a] = 0;
c = 0;
for (int sa=0; sa<samplesPerFrame; sa++) {
t = map(frameCount-1 + sa*shutterAngle/samplesPerFrame, 0, numFrames, 0, 1);
draw_();
loadPixels();
for (int i=0; i<pixels.length; i++) {
result[i][0] += pixels[i] >> 16 & 0xff;
result[i][1] += pixels[i] >> 8 & 0xff;
result[i][2] += pixels[i] & 0xff;
}
}
loadPixels();
for (int i=0; i<pixels.length; i++)
pixels[i] = 0xff << 24 |
int(result[i][0]*1.0/samplesPerFrame) << 16 |
int(result[i][1]*1.0/samplesPerFrame) << 8 |
int(result[i][2]*1.0/samplesPerFrame);
updatePixels();
saveFrame("f###.gif");
if (frameCount==numFrames)
exit();
}
}
//////////////////////////////////////////////////////////////////////////////
int samplesPerFrame = 4;
int numFrames = 300;
float shutterAngle = .4;
boolean recording = false;
int n = 1200;
float r = 200;
float x_, y_;
float x(float q){
x_ = r*sin(5*q);
y_ = r*.4*cos(5*q);
return x_*cos(q) + y_*sin(q);
}
float y(float q){
x_ = r*sin(5*q);
y_ = r*.4*cos(5*q);
return y_*cos(q) - x_*sin(q);
}
float h = 1e-4;
float xp(float q){
return (x(q+h/2)-x(q-h/2))/h;
}
float yp(float q){
return (y(q+h/2)-y(q-h/2))/h;
}
float xpn(float q){
return xp(q)/dist(xp(q),yp(q),0,0);
}
float ypn(float q){
return yp(q)/dist(xp(q),yp(q),0,0);
}
float amt, th, dr = 1;
int nw = 72;
void knot(float ph){
beginShape();
for(int i=0; i<n; i++){
th = PI*i/n;
amt = map(cos(2*th-TWO_PI*t),1,-1,0,1);
amt = 14*ease(constrain(1.7*amt-0.7,0,1),4.5);
vertex(x(th)+amt*sin(nw*th+ph+dr*TWO_PI*t)*ypn(th),y(th)-amt*sin(nw*th+ph+dr*TWO_PI*t)*xpn(th));
}
endShape(CLOSE);
}
void setup() {
size(540,540,P3D);
blendMode(MULTIPLY);
smooth(8);
result = new int[width*height][3];
rectMode(CENTER);
noFill();
strokeWeight(7);
}
float x, y, z, tt;
int N = 12;
void draw_() {
background(250);
push();
translate(width/2, height/2);
translate(0,12);
scale(1);
strokeWeight(3);
stroke(#39CCCC);
knot(0);
stroke(#FFDC00);
knot(TWO_PI/3);
stroke(#F71BC8);
knot(2*TWO_PI/3);
pop();
}
@shaunlebron

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