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HDC's

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Join Date: Jul 2007

Posts: 15

Reputation: Fromethius is an unknown quantity at this point

Solved Threads: 0

Fromethius Fromethius is offline

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HDC's

Jul 24th, 2007

Hello everyone,

I have this code:

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   Image* newImage = Image::FromFile(szFileName);
   Bitmap image(50, 50);
   Graphics graphics(&image);
   HDC gfxHDC = graphics.GetHDC();
   graphics.DrawImage(newImage, 0, 0);
   int pixel, row;
   for (pixel = 1, row = 1; row <= 50; pixel++)
   if (GetPixel(gfxHDC, pixel, row) != RGB(255, 255, 255))
   Image* newImage = Image::FromFile(szFileName);
   Bitmap image(50, 50);
   Graphics graphics(&image);
   HDC gfxHDC = graphics.GetHDC();
   graphics.DrawImage(newImage, 0, 0);
   int pixel, row;
   for (pixel = 1, row = 1; row <= 50; pixel++)
   if (GetPixel(gfxHDC, pixel, row) != RGB(255, 255, 255))

Anyways, whenever I use GetPixel, the IF statement ALWAYS runs. Even if it is a completely white image. I suspect that either DrawImage isn't drawing it onto gfxHDC or that GetPixel isn't reading the pixels from gfxHDC or I don't even know. The point is, it isn't working and I need some help.

Thanks.

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Join Date: Jun 2005

Posts: 1,496

Reputation: WolfPack has a spectacular aura about

Solved Threads: 104

WolfPack

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Mentally Challenged Mod.

Re: HDC's

Jul 24th, 2007

Get the return value of GetPixel and RGB functions to seperate variables. See if the values are infact what you expect, rather than just comparing them.

Also read the remarks section of the GetPixel documentation.

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