pakt01
See /software/p5js/pakt-februari/pakt01/ for a JavaScript version and /software/supercollider/februari-pakt/pakt01/ 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 pakt01App : public App {
public:
void setup();
void draw();
int index, n;
};
void pakt01App::setup() {
index= 0;
n= 75;
}
void pakt01App::draw() {
float x= getWindowCenter().x;
float y= getWindowCenter().y;
float w= getWindowWidth()*0.25;
float h= getWindowHeight()*0.25;
float yellow= sin(index*0.0005)*0.3+0.65;
cairo::Context ctx(cairo::createWindowSurface());
cairo::GradientRadial radialGrad(getWindowCenter(), 0, getWindowCenter(), getWindowWidth());
radialGrad.addColorStop(0, Color(1, 1, yellow));
radialGrad.addColorStop(1, Color(0, 0, 0));
ctx.setSource(radialGrad);
ctx.paint();
//double dashes[]= {sin(index*0.0023)*50.0+51, cos(index*0.0023)*50.0+51};
//ctx.setDash(dashes, 2, 0);
for(int i= 0; i<n; i++) {
float xx= x+(cos(i*0.2)*w);
float yy= y+(sin(i*0.15)*h);
float start= cos(index*((i+1)*0.00006))*2*M_PI;
float end= sin(index*((i*1)*0.00008))*2*M_PI;
float size= sin(index*0.01+i)*50+58;
ctx.setSourceRgba(xx/getWindowWidth(), yy/getWindowHeight(), yellow, end/2*M_PI);
//ctx.setLineWidth(0.5);
//ctx.arc(xx, yy, size, 0, 2*M_PI);
//ctx.stroke();
ctx.setLineWidth(i/8.0+4);
ctx.arc(xx, yy, size, start, start+end);
ctx.stroke();
}
index++;
}
CINDER_APP(pakt01App, Renderer2d, [&]( App::Settings *settings ) {
settings->setWindowSize( WIDTH, HEIGHT );
settings->setResizable( false );
})