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Bleuje/sierpinskitriangleloop.pde

Last active April 23, 2023 10:51
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sierpinskitriangleloop.pde
// code updates are now there:
// https://github.com/Bleuje/processing-animations-code/blob/main/code/sierpinskiloop/sierpinskiloop.pde
// Processing code by Etienne JACOB
// motion blur template by beesandbombs
// See the license information at the end of this file.
// View the rendered result at: https://twitter.com/etiennejcb/status/1367173073250758661
int[][] result;
float t, c;
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);
}
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("fr###.gif");
println(frameCount,"/",numFrames);
if (frameCount==numFrames)
exit();
}
}
// end of template
//////////////////////////////////////////////////////////////////////////////
int samplesPerFrame = 5;
int numFrames = 180;
float shutterAngle = .6;
boolean recording = false;
int DEPTH = 5; // recursion depth
float SWMAX = 3.0; // stroke weight max
float R = 300; // size of drawing
void setup(){
size(600,600,P3D);
result = new int[width*height][3];
}
// v1,v2,v3 are the vertices of a current triangle to draw, this function is recursive
// it is the current index of iterations
// p is a time parameter
void drawFractal(int it,PVector v1,PVector v2,PVector v3,float p)
{
if(it>=DEPTH) return;
float sw = map(it+p,0,DEPTH,SWMAX,0);
strokeWeight(sw);
triangle(v1.x,v1.y,v2.x,v2.y,v3.x,v3.y);
// now let's draw the triangles inside...
PVector u1 = v1.copy().add(v2).mult(0.5); // position at the middle between v1 and v2
PVector u2 = v2.copy().add(v3).mult(0.5); // position at the middle between v2 and v3
PVector u3 = v3.copy().add(v1).mult(0.5); // position at the middle between v3 and v1
drawFractal(it+1,v1,u1,u3,p);
drawFractal(it+1,u1,v2,u2,p);
drawFractal(it+1,u3,u2,v3,p);
}
// first level with some new fractal triangles coming in
void drawThing(float p,PVector v1,PVector v2,PVector v3)
{
PVector u1 = v1.copy().add(v2).mult(0.5); // position at the middle between v1 and v2
PVector u2 = v2.copy().add(v3).mult(0.5); // position at the middle between v2 and v3
PVector u3 = v3.copy().add(v1).mult(0.5); // position at the middle between v3 and v1
PVector w1 = v2.copy().lerp(u1,p); // go from v2 to u1 with time
PVector w2 = v2.copy().lerp(u2,p); // go from v2 to u2 with time
PVector w3 = v3.copy().lerp(u2,p); // go from v3 to u2 with time
PVector w4 = v3.copy().lerp(u3,p); // go from v3 to u3 with time
drawFractal(0,v1,w1,w4,p);
drawFractal(0,w1,v2,w2,p);
drawFractal(0,w4,w3,v3,p);
}
void draw_(){
background(0);
push();
translate(width/2,height/2+50);
noFill();
blendMode(ADD);
for(int col=0;col<3;col++) // RGB chromatic aberration loop
{
stroke(255*int(col==0),255*int(col==1),255*int(col==2));
// defining the main triangle vertices' positions
float a1 = TWO_PI*0.0/3.0-HALF_PI;
PVector v1 = new PVector(R*cos(a1),R*sin(a1));
float a2 = TWO_PI*1.0/3.0-HALF_PI;
PVector v2 = new PVector(R*cos(a2),R*sin(a2));
float a3 = TWO_PI*2.0/3.0-HALF_PI;
PVector v3 = new PVector(R*cos(a3),R*sin(a3));
strokeWeight(SWMAX);
triangle(v1.x,v1.y,v2.x,v2.y,v3.x,v3.y);
int N = 16;
for(int i=0;i<N;i++){ // drawing the fractal N times, changing the time with little delays (trail effect)
float t2 = 3*t + 0.011*col + 0.0015*i; // delay both based on R, G or B color, and on i of the loop*
float rot = floor(t2)%3; // we draw the scene with 3 different successive rotations
float q = t2%1; // fractional part for time inside current rotation
push();
rotate(TWO_PI*rot/3);
drawThing(ease(constrain(q,0,1),2.1),v1,v2,v3);
pop();
}
}
blendMode(NORMAL);
pop();
}
/* License:
*
* Copyright (c) 2021, 2023 Etienne Jacob
*
* All rights reserved.
*
* This code after the template and the related animations are the property of the
* copyright holder. Any reproduction, distribution, or use of this material,
* in whole or in part, without the express written permission of the copyright
* holder is strictly prohibited.
*/
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