[Bf-committers] 64 bits migration, windows/unix

[Ton Roosendaal]

Hi,

We'll have to define the Blender standard for migrating to 64 bits for  
all platforms... unfortunately the unix and windows worlds haven't  
adopted the same standard...

Check this diagram;
http://developer.apple.com/macosx/images/lp64compare.gif

The key difference is that;

- Windows keeps the "long" 32 bits in all cases, for unix it is 32 or  
64 bits.
- Windows doesn't have a "long long" (int64 instead).

With Blender's unix origins - already tested for 32/64 bits in the past  
- it would be simplest to investigate if we can typedef/define the  
Windows version to follow the LP64 standard.
If we can do that, no further #ifdef exceptions are needed to patch our  
code to be 32/64 bits compliant for all platforms.

So, I would like a Windows 64 bits developer to check on the following;

1) Patch BLI_winstuff.h

Something like this could work: (blenloader/intern/genfile.c uses it)

#ifdef WIN32
typedef long long __int64;
#endif

#ifdef WIN64
typedef long long __int64;
typedef long __int64
#endif

One note though... the BLI_winstuff.h is only included in the  
blender/source/ tree, not for our blender/intern/ and blender/extern/  
libraries. These each have to be checked on 32/64 issues as well.

2) Cleanup of platform #defines

We now already use a mix of WIN32 and _WIN32 to patch OS specific code,  
this is in all cases not 32 bits related, so we need a new generic  
define.

I hope Microsoft / Cygwin has another standard already. This better not  
gets patched in the BLI_winstuff.h, since we also have an intern and  
extern libraries to take care of.

3) Verifying DWORD referrals

In the Blender code are a couple of windows-only functions or C files.
Check the MSDB website for the porting guides for 64 bits, with several  
notes on proper 32/64 bits code.


-Ton-

------------------------------------------------------------------------ 
--
Ton Roosendaal  Blender Foundation ton at blender.org  
http://www.blender.org