pakt25
See /software/p5js/pakt-februari/pakt25/ for a JavaScript version and /software/supercollider/februari-pakt/pakt25/ 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 pakt25App : public App {
public:
void setup();
void draw();
cairo::SurfaceImage srfOff;
cairo::Context ctxOff;
int index;
float w, h;
int n;
};
void pakt25App::setup() {
srfOff= cairo::SurfaceImage(WIDTH, HEIGHT, false);
ctxOff= cairo::Context(srfOff);
ctxOff.setLineWidth(0.5);
index= 0;
w= getWindowWidth();
h= getWindowHeight();
}
void pakt25App::draw() {
n= sin(index*0.0006f)*15+20;
cairo::Context ctx(cairo::createWindowSurface());
ctxOff.setSourceRgba(0, 0, 0, 0.02);
ctxOff.paint();
ctxOff.setSourceRgba(1, 1, 1, 1);
ctxOff.moveTo(0, h*0.5);
for(int i= 0; i<n; i++) {
float t= float(i)/(n-1);
ctxOff.quadTo((t-(0.5f/n))*w, h*(sin(index*(sin(index*0.006f)*0.02f)+t)*0.5f+0.5f), t*w, h*(cos(index*(sin(index*0.002f)*0.02f)+t)*0.5f+0.5f));
}
ctxOff.stroke();
index++;
ctx.copySurface(srfOff, srfOff.getBounds());
}
CINDER_APP(pakt25App, Renderer2d, [&]( App::Settings *settings ) {
settings->setWindowSize( WIDTH, HEIGHT );
settings->setResizable( false );
})