public static extern bool LineDDA(int xStart, int yStart, int xEnd, int yEnd, LINEDDAPROC lpProc, IntPtr data);
public static extern bool LineDDA(int xStart, int yStart, int xEnd, int yEnd, LINEDDAPROC lpProc, [MarshalAs(UnmanagedType.SysInt)] IntPtr data);
public static extern int LineDDA(int n1, int n2, int n3, int n4, LINEDDAPROC lpLineDDAProc, IntPtr lParam);
public static extern bool LineDDA(int x1, int y1, int x2, int y2, LINEDDAPROC callback, IntPtr lParam);