Tech Soft 3D • HOOPS

HOOPS_MFC UNICODE

by Reuben Hawkins

We are no longer shipping non-unicode hoops_mfc libs or dlls. If you're not already building a Unicode MFC app, you'll either need to update your code to work with Unicode MFC or recompile hoops_mfc for non-Unicode apps.

So what does it mean to compile a Unicode application anyway?

All applications have Unicode capabilities. That is, all modern compilers support the wchar_t type and the Universal Character Set (UCS and ISO-10646). A Unicode application in the Microsoft world means we're using the wide character versions of the MFC classes and functions. For example, MessageBox in a non-unicode application maps to MessageBoxA when a unicode application maps MessageBox to MessageBoxW. Also, the MFC defined string types, CString, TCHAR, LPCSTR, etc, map to narrow character types (char) in non-unicode and wide character types (wchar_t) in unicode applications. To use the Unicode version of MFC, define “_UNICODE” in the preprocessor macros in your application's properties.

It is possible to write code which will compile in both Unicode and non-Unicode MFC applications. To write code that compiles in both requires using Microsoft's _t and _T functions and macros.

For example, this is NOT portable...

char example[100] = {“”};
strcpy(example, “test”);
MessageBox(0, example, “Caption”, MB_OK);

But this is portable to both Unicode and non-Unicode applications...

TCHAR example[100] = {_T(“”)};
_tcscpy(example, _T(“test”));
MessageBox(0, example, _T(“Caption”), MB_OK);

Be sure to only use these types (TCHAR, Cstring, LPCSTR, etc) and the t functions (_tcsstr, _tcscat, etc) when interfacing with MFC code. Never pass TCHAR types to HOOPS or use _tcscmp (and other _tcs functions) with a string returned by HOOPS.

What if I don't want to convert my application to Unicode?

If your application is non-Unicode and makes too many assumptions that TCHAR is a char type, you can still compile the non-Unicode version of hoops_mfc (although is it highly recommended that you eventually port your code to be compatible with both Unicode and non-Unicode versions of MFC).

To compile non-Unicode hoops_mfc, open the project setting for hoops_mfc by right clicking the project in the solution explorer and selecting “Properties.” In the Properties page, navigate to Configuration Properties->C/C++->Preprocessor and remove UNICODE from the Preprocessor Definitions. You may also want to rename the output to hoops_mfc17XX.dl l under Linker->General and hoops_mfc17XX.lib under Linker->Advanced.