Copying an image by using a rectangle?

Hi everyone, is there any way in c++ to take a region (by using a rectangle) and copy its contents to redraw it later? I am trying to make a map editor and update my map. Whenever I resize the window, the map disappears. I want to copy the image when the window is resized and redraw it after it is resized. Please help.





Ryan

Copying an image by using a rectangle?
Where hdc is your window's device context and





HDC memdc;


HBITMAP membmp;


HBITMAP oldbmp;





are globals, use this code to construct buffer:





memdc = CreateCompatibleDC(hdc);


membmp = CreateCompatibleBitmap(hdc, width, height);


oldbmp = SelectObject(memdc, membmp);





Then use BitBlt function to copy to and from buffer.





Don't forget to call





SelectObject(memdc, oldbmp);


DeleteDC(memdc);


DeleteObject(membmp);





when done with buffer.