Erasing rectangles -- dotnet drawing api

dotnet drawing api : Erasing rectangles

Landley
11/9/2004 12:40:01 AM

I have a panel with a gradient filled background. I have drawn a rectangle
on top in a solid color and wish to cut a smaller rectangle out it,
revealing the gradient filled background.

I am having problems trying to find a method or brush that I can use that
will in effect perform as an eraser.

Can you help?

Landley
11/9/2004 1:00:47 AM

The problem is that the gradient on a third party control. So I do not have
the details that I require to redraw it. Sorry, I should have mentioned
this.

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Bob Powell [MVP]
11/9/2004 1:45:54 AM

You'll have to re-draw the background. Calculating the right gradient for
the rectangle is next to impossible.

--
Bob Powell [MVP]
Visual C#, System.Drawing

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James Westgate
11/9/2004 2:43:08 AM

If you are drawing using a graphics object then you can use a GraphicsPath.
Add the larger then smaller rectangle to the same graphicspath then draw the
path.

James

--
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Doug Forster
11/9/2004 2:17:36 PM

Hi Landley,

Look up Graphics.SetClip and CombineMode.Exclude and see if that helps.

Cheers

Doug Forster

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Peder Y
11/10/2004 9:24:32 PM

....or redefine the path that the gradient is painting inside, and do an
invalidate(...) call.

- Peder -

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