See my comment for a drawing of the angle.

float t=millis();
float cx=width/2;
float cy=height/2;

Excecuted for every pixel:
float angle=atan2(x-cx,y-cy); //cx and cy is the centerpoint of the image
float dist=dis(x,cx,y,cy); //distance between the centerpoint and xy coordinates
float value = noise(dist/100.0-t/5000)*600*noise(sin(angle*1.5+t/2000)*1.5);
int clr=color(int(value)&0xff,255,255);
set(x,y,clr);

float dis(float x1,float x2,float y1,float y2){
return sqrt(sq(x2-x1)+sq(y2-y1));
}

свернуть