Swapping buffer

I am now working on an OpenGL application which uses Double buffers. Something are drawn in the front-buffer, such as mouse-line; lots of others are drawn in back-buffer, which is time-consuming. So instead of redrawing the back buffer each time, I just swapped its content to the front with the assumption that it will not be changed by swapping. But on some computers, the behavior of swapping is to exchange the content of front buffer and that of back buffer, not just to copy backbuffer to front buffer. Any suggestion?

Copy first from back buffer to central memory and then from central memory to front buffer

But it’s really not a good thing because it’s TOO SLOW !!!

When can we found a good, simple and fast glDrawWithoutPixelTransfertEXT() func : on OpenGL v147.8beta4 ???

When we think that only simples pointers to the back and front buffer can resolve this on a majority of cases … (but here, it’s another story )


Is it possible to draw on layers?