bool validate_region(handle window, handle region)
This function validates a region by removing it from the window's update region.
The handle of the window whose update region is being modified.
The handle of a region that is to be removed from the update region of the window. If this parameter is null, the entire client area is validated.
|true||The region was successfuly validated.|
|false||The call failed.|
The coordinates of the region are assumed to be client coordinates.
The function begin_paint automatically validates the entire client area.