all you have to do it change a line in canvas.h -> createImaeRep method

NSBitmapImageRep *imageRep = [[NSBitmapImageRep alloc] initWithBitmapDataPlanes:nil
pixelsWide:size.width
pixelsHigh:size.height
bitsPerSample:8
samplesPerPixel:4
hasAlpha:YES
isPlanar:NO
colorSpaceName:NSCalibratedRGBColorSpace
bitmapFormat:0
bytesPerRow:rowBytes
bitsPerPixel:32];

hope it helps someone

Ahh, I remember the good old days. The 45° striped pattern, some QuickDraw region twiddling, and XOR drawing. No need to redraw the whole window, you just XORed the old pattern, advanced the pattern (eight shifts) and XORed in the new pattern.

I wonder if it would still look good or if there is a need to fit Bezier curves to the 1-pixel line segment data.

I think you would have to fit it to bezier curves in order for it to look good scaled up. The 1-pixel line segments would definitely alias if you scaled them up. Unfortunately, once you fit them to curves, you won’t have a per-pixel accurate representation of the selection, because the curves won’t fit perfectly.

* a chessboard pattern (ok, somebody beat me on that in the comments)
* applying a rotation to it at each step of the marching ants, using an appropriate center

For example, if you clicked on the blue circle, would the resulting NSBezierPath still look good if it were scaled to be much larger?

I wonder if it would still look good or if there is a need to fit Bezier curves to the 1-pixel line segment data.

Thanks for the awesome articles. I am learning a lot!

I’ve found that a chessboard pattern (each of the squares 4×4 pixels) works better than stripes.