Hi,
i tried to make a sketch which projects an image like a fisheye camera lens.
I searched a while how to do it and found this formula for MathMap:

filter fisheye (image in)
   in(ra:[r*r/R,a])
end
(http://www.complang.tuwien.ac.at/schani/mathmap/stills.html)
Example picture: http://www.gdargaud.net/Photo/Fisheye/20050606_FisheyeChristophe2.jpg

I don't know how to adopt it to the cartesian coodinatesystem.

Here's my basic sketch:

PImage img1;
float r;  // Radius from specific point to the middle (width/2, height/2)
float rMax;  //Max Radius = Distance from the middle to a corner

void setup()
{
 size(640, 480, P2D);
 img1 = loadImage("img.jpg");
 img1.resize(640, 480);
 rMax = dist(0, 0, width/2, height/2);
}

void draw()
{
 loadPixels();
 img1.loadPixels();
 
 for(int x=0 ; x<width; x++)
 {
   for(int y=0; y<height; y++)
   {
     r = dist(width/2, height/2, x, y);
    //pixels[y*width+x] = img1.pixels[ ... ];
   }
 }
 updatePixels();
}


Would be really nice if someone can help me!
Greetings Tim

Wouldnt that be a good start for a ImageFilter/manipulation Librarie for Processing ?Does something like this already exist ?