Drawing a subset of a picture into the same area of another picture?

I’ve played around with all sorts of different combinations of .drawPicture but can’t seem to find the right way to do this; the documentation is maddeningly vague about whether it’s even possible.

Assume I have two pictures A and B of the same size, and I have a rectangular area specified by Top,Left,Width,Height – in effect, a clipping region.

I want to copy that area from B to A, leaving everything else untouched. As it happens, everything outside the area is empty, so a simple A.drawPicture B,0,0 works fine, but it would be nice to make it faster.

Also, pointers to documentation on how to do graphics operations faster in RealBa… er, Xojo… would be helpful.

using DrawPicture is exactly how you want to do it

apicture.graphics.drawpicture bpicture,left,top,width,height, left,top,width,height ’ move a rectangle from a to b in same x,y location, same size

I have routines that do similar things at 30+ frames per second… how fast do you need it to be???