How to exclude a rectangular area from another rectangular area

[han1548772930]

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		Gdiplus::Graphics graphics(dcCompatible);

		HRGN hgn1 = CreateRectRgn(m_rectTracker.m_rect.left,m_rectTracker.m_rect.top,
			m_rectTracker.m_rect.right,m_rectTracker.m_rect.bottom);
		Region region1(hgn1);

		HRGN hgn2 = CreateRectRgn(rect.left,rect.top,
			rect.right,rect.bottom);
		Region region2(hgn2);

		region2.Exclude(&region1);

		SolidBrush  solidBrush(Color(100, 128, 128, 128));
		graphics.FillRegion(&solidBrush,&region2);

		DeleteObject(hgn1);
		DeleteObject(hgn2);