// Rebuild new region from previous one
public static void BuildRegion(IntPtr hWnd)
{
IntPtr hRgnClip = IntPtr.Zero;
ApiWin32.RECT rw = new ApiWin32.RECT();
ApiWin32.GetWindowRect(hWnd, ref rw);
int RgnWidth = rw.Right - rw.Left, RgnHeight = rw.Bottom - rw.Top;
// Avoid changing region when iconized !
if (RgnHeight < DockMin)
{
return;
}
if ((LastRgnWidth == RgnWidth) && (LastRgnHeight == RgnHeight))
{
return;
}
IntPtr hRgn = ApiWin32.CreateRectRgn(0, 0, 0, 0);
if (hRgn != IntPtr.Zero)
{
if (ApiWin32.GetWindowRgn(hWnd, hRgn))
{
hRgnClip = ApiWin32.CreateRectRgn(0, 0, RgnWidth, RgnHeight);
if (hRgnClip != IntPtr.Zero)
{
// Top left corner.
int rgnX = 0; int rgnY = 0;
CombineRegion(ref hRgnClip, hRgn, 0, 0, FixCaptionLeft, FixCaptionHeight, rgnX, rgnY);
// Top right corner.
rgnX = -LastRgnWidth + FixCaptionRight; rgnY = 0;
CombineRegion(ref hRgnClip, hRgn, RgnWidth - FixCaptionRight, 0, FixCaptionRight, FixCaptionHeight, rgnX, rgnY);
// Bottom left corner.
rgnX = 0; rgnY = -LastRgnHeight + FixBottomHeight;
CombineRegion(ref hRgnClip, hRgn, 0, RgnHeight - FixBottomHeight, FixCaptionLeft, FixBottomHeight, rgnX, rgnY);
// Bottom right corner.
rgnX = -LastRgnWidth + FixCaptionRight; rgnY = -LastRgnHeight + FixBottomHeight;
CombineRegion(ref hRgnClip, hRgn, RgnWidth - FixCaptionRight, RgnHeight - FixBottomHeight, FixCaptionRight, FixBottomHeight, rgnX, rgnY);
Form.FromHandle(hWnd).BackgroundImage = (Bitmap)SkinEngine.DrawBackGround(RgnWidth, RgnHeight);
// Set the new region to the form.
ApiWin32.SetWindowRgn(hWnd, hRgnClip, false);
// Save the new region size
LastRgnWidth = RgnWidth; LastRgnHeight = RgnHeight;
}
}
ApiWin32.DeleteObject(hRgn);
}
}
// Combine child regions altogether.
public static void CombineRegion(ref IntPtr hRgnClip, IntPtr hRgn, int xOffset, int yOffset, int bmW, int bmH, int rgnX, int rgnY)
{
IntPtr hRgnTemp = ApiWin32.CreateRectRgn(0, 0, bmW, bmH);
ApiWin32.OffsetRgn(hRgnTemp, xOffset, yOffset);
ApiWin32.CombineRgn(hRgnClip, hRgnClip, hRgnTemp, ApiWin32.RGN_DIFF);
ApiWin32.OffsetRgn(hRgnTemp, -xOffset, -yOffset);
hRgnTemp = ApiWin32.CreateRectRgn(0, 0, bmW, bmH);
ApiWin32.OffsetRgn(hRgn, rgnX, rgnY);
ApiWin32.CombineRgn(hRgnTemp, hRgnTemp, hRgn, ApiWin32.RGN_AND);
ApiWin32.OffsetRgn(hRgn, -rgnX, -rgnY);
ApiWin32.OffsetRgn(hRgnTemp, xOffset, yOffset);
ApiWin32.CombineRgn(hRgnClip, hRgnClip, hRgnTemp, ApiWin32.RGN_OR);
ApiWin32.DeleteObject(hRgnTemp);
}