void HandleMouseMove(IntPtr handle, WindowMessage message, IntPtr wParam, IntPtr lParam)
{
unsafe
{
Point point = new Point(
(short)((uint)lParam.ToInt32() & 0x0000FFFF),
(short)(((uint)lParam.ToInt32() & 0xFFFF0000) >> 16));
// GetMouseMovePointsEx works with screen coordinates
Point screenPoint = point;
Functions.ClientToScreen(handle, ref screenPoint);
int timestamp = Functions.GetMessageTime();
// & 0xFFFF to handle multiple monitors http://support.microsoft.com/kb/269743
MouseMovePoint movePoint = new MouseMovePoint()
{
X = screenPoint.X & 0xFFFF,
Y = screenPoint.Y & 0xFFFF,
Time = timestamp,
};
// Max points GetMouseMovePointsEx can return is 64.
const int numPoints = 64;
MouseMovePoint* movePoints = stackalloc MouseMovePoint[numPoints];
// GetMouseMovePointsEx fills in movePoints so that the most
// recent events are at low indices in the array.
int points = Functions.GetMouseMovePointsEx(
(uint)MouseMovePoint.SizeInBytes,
&movePoint, movePoints, numPoints,
Constants.GMMP_USE_DISPLAY_POINTS);
int lastError = Marshal.GetLastWin32Error();
// No points returned or search point not found
if (points == 0 || (points == -1 && lastError == Constants.ERROR_POINT_NOT_FOUND))
{
// Just use the mouse move position
OnMouseMove(point.X, point.Y);
}
else if (points == -1)
{
throw new System.ComponentModel.Win32Exception(lastError);
}
else
{
// Exclude the current position.
Point currentScreenPosition = new Point(MouseState.X, MouseState.Y);
Functions.ClientToScreen(handle, ref currentScreenPosition);
// Find the first move point we've already seen.
int i = 0;
for (i = 0; i < points; ++i)
{
if (movePoints[i].Time < mouse_last_timestamp)
break;
if (movePoints[i].Time == mouse_last_timestamp &&
movePoints[i].X == currentScreenPosition.X &&
movePoints[i].Y == currentScreenPosition.Y)
break;
}
// Now move the mouse to each point before the one just found.
while (--i >= 0)
{
Point position = new Point(movePoints[i].X, movePoints[i].Y);
// Handle multiple monitors http://support.microsoft.com/kb/269743
if (position.X > 32767)
{
position.X -= 65536;
}
if (position.Y > 32767)
{
position.Y -= 65536;
}
Functions.ScreenToClient(handle, ref position);
OnMouseMove(position.X, position.Y);
}
}
mouse_last_timestamp = timestamp;
}
if (mouse_outside_window)
{
// Once we receive a mouse move event, it means that the mouse has
// re-entered the window.
mouse_outside_window = false;
EnableMouseTracking();
OnMouseEnter(EventArgs.Empty);
}
}
unsafe internal static extern int GetMouseMovePointsEx(
uint cbSize, MouseMovePoint* pointsIn,
MouseMovePoint* pointsBufferOut, int nBufPoints, uint resolution);
