[Bf-committers] [Bf-blender-cvs] SVN commit: /data/svn/bf-blender [15734] trunk/blender/source/blender/ blenkernel/intern/softbody.c: soft body bug fix own finding

[bjornmose]

Diego Hernan Borghetti schrieb:
> On Thu, 24 Jul 2008, bjornmose wrote:
>
>   
>> Martin Poirier schrieb:
>>     
>>> --- On Thu, 7/24/08, Jens Ole Wund <bjornmose at gmx.net> wrote:
>>>
>>>
>>>       
>>>> Revision: 15734
>>>>
>>>> http://projects.blender.org/plugins/scmsvn/viewcvs.php?view=rev&root=bf-blender&revision=15734
>>>> Author:   bjornmose
>>>> Date:     2008-07-24 14:27:31 +0200 (Thu, 24 Jul 2008)
>>>>
>>>> Log Message:
>>>> -----------
>>>>
>>>>         
>>> <snip>
>>>
>>>
>>>       
>>>> -adapted effect of wind and fields on softbodies such that
>>>> softbody "particles" and particle
>>>> "particles" behave consistently
>>>> note!
>>>> effect of wind is 1/25 compared to before
>>>> other forces 1/10
>>>>
>>>>         
>>> Hi,
>>>
>>> Wouldn't it be good to add some do versions code in that case so that old files work consistently (backward compat) after this change?
>>>
>>> Martin
>>>
>>>
>>>
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>>>
>>>
>>>       
>> Would be nice to be backward compatible. But, that is not that easy.
>> Wind and other effectors settings work layer global on all objects, that
>> is particles and soft bodies.
>> The problem is there is no convention on the units, so every system
>> scales it ad hoc.The scale constants are hard coded and not stored in
>> the .blend.
>> It is even worse, since some of the effectors yield direct forces
>> instead of indicating a media moving, which is physically wrong and the
>> softbody code cares for that.
>> /* See: a particle in moving media (alias wind) will synchronize it's
>> motion to the meadia and not accelerate for ever as in a force field.
>> So seen strictly  effectors have to accumulate movement and forces
>> separatly .. AFAIK only soft bodies are asking the effectos to do that
>> And yes, the code is that bad :(  All i did try to hide the mess to
>> users **sigh**  */
>> Setting the scale values on object level while loading the file won't
>> work for several reasons:
>> 1. old files loaded will behave back compat until saved with the new
>> version tag
>> 2. for newly added effectors, should  the old scale be used or the new one?
>> 3. how to keep track on mixed effector --> victim realations .. storing
>> that matrix to the .blend is overkill IMHO and will lead to confusion
>> why objects act different depending on their 'birth date'.
>>
>> I'd be more than happy to resolve that but was running out of ideas to
>> do it right .. any help ?
>> BM
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>>
>>     
>
> Hello,
>
>   It's fine merge this to the stable branch now, or it's better wait a 
> little more to see if you found a solution to the backward problem ?
>
>   
I did roll back to the 'user confusing state' because i have no solution 
for this issue.