HDC's

Expand Post »

Hello everyone,

I have this code:

C++ Syntax (Toggle Plain Text)
   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.

Similar Threads

Want to write script to back-up up Linux hdb drive to hdc drice in Linux Kernel and Hardware Setup
Drawing bitmap on window - how to clear window/HDC? in C
Visual C++ Form Project - need to get HDC for drawing bitmaps in C++
a non-destructive repartitioning tool? in Linux Applications and Software
"missing storage-class or type specifiers" error in C++

Fromethius

Reputation Points: 10

Solved Threads: 0

Newbie Poster

Offline

15 posts
since Jul 2007

Permalink

Jul 24th, 2007

Re: HDC's

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.

WolfPack

Moderator

Reputation Points: 572

Solved Threads: 115

Mentally Challenged Mod.

Offline

1,559 posts
since Jun 2005

This thread is more than three months old

No one has posted to this discussion for at least three months. Please let old threads die and do not reply to them unless you feel you have something new and valuable to contribute that absolutely must be added to make the discussion complete. Otherwise, please start a new thread in this forum instead.

Previous Thread in C++ Forum Timeline: why return an int from main?

Next Thread in C++ Forum Timeline: Q: in Link List (Daubly Linked List)

DaniWeb Message

Cancel Changes

User Name
Password