BCGSuite for MFC
void CBCGPRect::Normalize ( )

Normalizes rectangle so that both the height and width are positive.

The rectangle is normalized for fourth-quadrant positioning, which Windows typically uses for coordinates. Normalize compares the top and bottom values, and swaps them if the top is greater than the bottom. Similarly, it swaps the left and right values if the left is greater than the right. This function is useful when dealing with different mapping modes and inverted rectangles.