Fractal images are a good reason to draw off-screen in high-resolution, as discussed in an earlier post. Looking at the low-resolution image of “self-similar fractals …” we need some imagination to see that it is really self-similar. Too much details are lost if we have only 600×600 pixels.
With say 6000×6000 pixels we get a much better picture. Still, at high magnification we would see again jagged contours and the images could be further improved by smoothing. A very simple method calculates four image points per pixel and uses their average. This is the same as calculating a 12000×12000 pixel image and showing it at half its resolution. Many jaggies are thus removed. But as this requires much more computer time and seconds become minutes it becomes important to print out a progress report on the console. You find the code in the next post. It needs the class OutputBuffer and the improved Vector class.
Here I am showing you a sample result. First, you see this in the windows photo viewer:
Then you can increase the magnification and shift the image around to see the part at the lower left:
This nicely shows the self-similarity and we could get a nice print from such an image file.