Re: How to draw Shapes with solid color, which is transparent?

From:
"AliR \(VC++ MVP\)" <AliR@online.nospam>
Newsgroups:
microsoft.public.vc.mfc
Date:
Thu, 29 Mar 2007 15:50:29 GMT
Message-ID:
<9fROh.12140$Um6.5007@newssvr12.news.prodigy.net>
Use GDI+, when you are creating your SolidBrush object use a color with some
Alpha.

Gdiplus::Graphics graphics(pDC->m_hDC);

SolidBrush TheBrush(Color(100,255,0,0));

graphics.FillRectangle(&TheBrush,Rect(0,0,100,100));

AliR.

"Soney" <Soney@discussions.microsoft.com> wrote in message
news:8E160441-C400-4CDE-AD66-770F1CFDBC69@microsoft.com...

I have loaded a bitmap to the SDI application and try to draw a shape
(ex:-
Rectangle, Circle, Elipse... ) above the bitmap. We are using
CreateSolidBrush() to fill the shape with the solid RED color.

How can i make the shape( Rectangle, Circle, Elipse...) backround as
transparent.
I am using the VC++6, MFC, GDI

Sample code:-

CBrush *pShadingBrush = new CBrush;
pShadingBrush->CreateSolidBrush( RGB( 255, 0, 0 ) );
pDC->SelectObject( pShadingBrush );
pDC->SetBkMode(TRANSPARENT);
pDC->FillRect( &Rect, pShadingBrush );

Using the above code, I am not able to see the bitmap area which is
occupied
by the shape, because the shape is filled with the solid red color but it
is
not transparent. Please advise using windows GDI is it possible or not?

Thanks in advance

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