pakt28
See /software/p5js/pakt-februari/pakt28/ for a JavaScript version and /software/supercollider/februari-pakt/pakt28/ for accompanying sound code.
#include "cinder/app/App.h"
#include "cinder/cairo/Cairo.h"
using namespace ci;
using namespace ci::app;
using namespace std;
const int WIDTH= 640;
const int HEIGHT= 480;
class pakt28App : public App {
public:
void setup();
void draw();
int index;
float w, h;
int n;
};
void pakt28App::setup() {
index= 0;
w= getWindowWidth()*0.5f;
h= getWindowHeight()*0.5f;
}
void pakt28App::draw() {
n= sin(index*0.0015f)*30.0f+35.0f;
cairo::Context ctx(cairo::createWindowSurface());
ctx.setSourceRgb(0, 0, 0);
ctx.paint();
for(int i= 0; i<n; i++) {
float t= float(i)/n*M_PI*2;
ctx.setLineWidth(sin(index*0.0125f+t)*5.0f+5.5f);
ctx.setSource(ColorA(CM_HSV, sin(t)*(sin(index*0.01f)*0.2f)+0.5f, sin(index*0.004f)*0.3f+0.7f, 1.0f, 1.0f));
float a1= (sin(index*(sin(index*0.0025f+t)*0.01f+0.01f))*0.5f+0.5f)*M_PI*2;
float a2= (sin(a1*index*0.0005f+t)*0.5f+0.5f)*M_PI;
float r= h*0.95f*(1.0f-float(i)/n);
ctx.arc(w, h, r, a1, a2);
ctx.stroke();
}
index++;
}
CINDER_APP(pakt28App, Renderer2d, [&]( App::Settings *settings ) {
settings->setWindowSize( WIDTH, HEIGHT );
settings->setResizable( false );
})