CDC::FloodFill
Visual Studio 2010
Fills an area of the display surface with the current brush.
BOOL FloodFill( int x, int y, COLORREF crColor );
The area is assumed to be bounded as specified by crColor. The FloodFill function begins at the point specified by x and y and continues in all directions to the color boundary.
Only memory-device contexts and devices that support raster-display technology support the FloodFill member function. For information about RC_BITBLT capability, see the GetDeviceCaps member function.
The ExtFloodFill function provides similar capability but greater flexibility.