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Difference in Graphics objects?

We use GDI code to do some drawing with R2_MASKPEN (because there doesn't
seem to be a GDI+ way of doing it). We're getting the HDC from a Graphics
object passed in to the method. This works fine if the Graphics was created
from a Form or Control, but when the Graphics object is created from an
Image, the result is black.

I tried using the Flush method before getting the HDC, but it only seems to
be a solid black image. I also tried getting an HBITMAP from the HDC, but
it's black as well.

The only difference I can see in these Graphics objects is the ClipBounds.
Does the Graphics object work differently if it's created from an Image? Any
idea how to work directly with the pixel data in a Graphics object?
Jul 21 '05 #1
1 1242
http://www.vbdotnetheaven.com/

Glenn wrote:
We use GDI code to do some drawing with R2_MASKPEN (because there doesn't
seem to be a GDI+ way of doing it). We're getting the HDC from a Graphics
object passed in to the method. This works fine if the Graphics was created
from a Form or Control, but when the Graphics object is created from an
Image, the result is black.

I tried using the Flush method before getting the HDC, but it only seems to
be a solid black image. I also tried getting an HBITMAP from the HDC, but
it's black as well.

The only difference I can see in these Graphics objects is the ClipBounds.
Does the Graphics object work differently if it's created from an Image? Any
idea how to work directly with the pixel data in a Graphics object?


Jul 21 '05 #2

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