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Introduction

If you did a GDI+ sample query on Google, I bet you will get hundreds or thousands of URLs pointing you to a .NET free code. If you go book shop you will see dozens of books talking about GDI+. However, if you try to find information about integrating GDI+ with MFC/ATL/WTL, I bet you will find none (if you could, kindly post the URL!). So, is it impossible or so difficult that it doesn't worth using?

Findings

The answer is: Extremely easy to use GDI+ in MFC/ATL/WTL, or even straight C language. First, I have to admit I have no knowledge about .NET, I am not a fan of Microsoft .NET but rather prefer platform SDK. GDI+ IS NOT solely for .NET, if you plan to use GDI+ on Windows version lower than XP, then you would have to redistribute the GDI+ runtime (here). Don't worry, it is only 1.04 MB, not a xx MB .NET runtime.

So?

• Add the following line to your stdafx.h

  #include <gdiplus.h>
      using namespace Gdiplus;
      #pragma comment(lib, "gdiplus.lib")

• Intialize the GDI+ resources. Add this to your CWinApp derived class as member:

  GdiplusStartupInput gdiplusStartupInput;
      ULONG_PTR gdiplusToken;

  At InitInstance(), add:

  GdiplusStartup(&gdiplusToken, &gdiplusStartupInput, NULL);

• Your application is ready to consume GDI+ now.
• Upon exit, release GDI+ resources. Add the following line to ExitInstance():

  GdiplusShutdown(gdiplusToken);

As you can see, it is that simple. In general, it should be very easy to port your existing WIN32/MFC/WTL painting code into GDI+. If you ask why? Consider there is one GDI+ C++ class called RedEyeCorrection, that's right, to correct the red eyes that sometimes occur in flash photographs. If you have at least one year WIN32/MFC experiences, just follow the link here to see more.

I included a demo project to demonstrate the above. Enjoy!

GDI+ is device context handle centric, hence if you can split drawing logic aside from actual drawing code, you will have no problem in porting to GDI+. In some cases, 100 lines of drawing code can be reduced to just 5 lines with GDI+ intensive support of complex drawing exercises. This means mixing ordinary GDI with GDI+ a trivial task.

The downloaded project is a standard MFC SDI project, if you have read it (I hope so...), you will find that it is unbelievable simple. Nearly all time, you can simply cut-n-paste source code embedded in MSDN GDI+ to try things out. One tips: if the GDI+ need to load an external file, you can just right click the image in the help and save it, then continue to use the downloaded project to continue testing.

Finally, you do need to have a copy of platform SDK to have necessary GDI+ header, library at your VC search path. It is not necessary for the latest version, I am using version Aug'02. GDI+ files can be extracted from CAB_11, if you do not want to install the SDK.

** Don't forget to visit here for more information on integrating GDI+ with Win32/MFC/ATL/WTL **