[Bf-committers] Changing mul_m4_m4m4 argument order

[Brecht Van Lommel]

I've committed the change now. We could indeed change the name back
after a while, though two weeks seems too short.

Brecht.

On Thu, Dec 15, 2011 at 10:39 PM, Sergey Sharybin <sergey.vfx at gmail.com> wrote:
> Hi,
>
> Argument order is indeed confusing. I've spend two hours debugging deep
> tracking stuff and then learned in which order i shall pass matrices in
> constraint which i used to check it tracking is correct.
>
> I can think about such quite safe for branches solution:
> - Create script which swaps arguments in mul_m*_m*m* functions and renames
> them to, say the save with suffix '_r' (from "reversed") or prefix "x"
> (like 64bit prefix for registers :)
> - Make changes in trunk and publish script
> - Give two weeks to everybody to merge changes and run that script for
> their own code
> - after this two weeks remove old mul functions are rename new function to
> old name
>
> Not very straight, but should be safe for everybody.
>
> Can think about ways which doesn't require temporary function, but think
> way with temporary functions is more safe.
>
> On Thu, Dec 15, 2011 at 8:51 PM, Brecht Van Lommel <
> brechtvanlommel at pandora.be> wrote:
>
>> Hi,
>>
>> The argument order of the mul_m4_m4m4 C math function is inconsistent
>> with the others. This has always been the case, but I only recently
>> found this out, it explains quite a bit of confusion I've had in the
>> past working with matrices. Python is not affected by this.
>>
>> For the details, see here:
>>
>> http://wiki.blender.org/index.php/Dev:Source/Mathematics/Math_Library#Matrix-Matrix_Multiplication
>>
>> It's easy to fix this in trunk, the main issue is for branches, just
>> changing the order of arguments to mul_m4_m4m4 will not show up as
>> conflicts in merges. A solution would be to change the function to a
>> different name. Do you think this is needed, and does anyone have a
>> good suggestion for a different name? I guess that would also cause
>> some confusion, but hopefully much less.
>>
>> Thanks,
>> Brecht.
>> _______________________________________________
>> Bf-committers mailing list
>> Bf-committers at blender.org
>> http://lists.blender.org/mailman/listinfo/bf-committers
>>
>
>
>
> --
> With best regards, Sergey Sharybin
> _______________________________________________
> Bf-committers mailing list
> Bf-committers at blender.org
> http://lists.blender.org/mailman/listinfo/bf-committers