[PD] Gem gemlist_info and gemlist_matrix

[Max]

bonjour cyrille,

I see, so it's because i'm messing with the view message to change the angle towards the object in my gem scene. So gemlist_info is always referring to the camera in gem, that's important to understand and it means i can't use it what I thought I'd use it for. Actually I just wanted to rotate a point in the space and I was too lazy for the algebra. There must be some abstractions for that and I think I saw some in the PdMtl… tomorrow.

bonne nuit,
m.

Am 06.09.2012 um 00:06 schrieb Cyrille Henry:

> hello Max,
> 
> about gemlist_info :
> on gemlist_info help patch, the default position is 0 0 -4, rotation, and shear are 0 0 0, size is 1 1 1.
> changing the translate to 0 0 4 result having the gemlist_info position to 0 0 0.
> adding the rotation before the translation will result in a different translation (because it was rotated). So the position will not be 0 0 0 any more.
> 
> since the 1st transformation comes from the camera position and rotation, playing with camera position can result in the value you describe.
> 
> 
> 
> about gemlist_matrix :
> 
> this object output a 4x4 matrix. but since pd did not have a native matrix type, the 16 float are output as a list.
> 
> cheers
> c
> 
> 
> Le 05/09/2012 23:46, Max a écrit :
>> dear list,
>> 
>> i'm wondering how the gemlist_info and gemlist_matrix objects work. gemlist_info for instance has a default position of x, y, z: 0, -2.38419e-07, -13.0551
>> which i found strange, so i thought i'd add a translateXYZ 0 2.38419e-07 13.0551 before the gemlist_info to get reset the position to zero. but then i get 7.30032, -10.4295, -10.1628
>> that seems very strange to me can someone enlighten me?
>> the gemlist_matrix-help seems very incomplete, it doesn't explain what difference of the matrix and the list is and what the output values $1…$15 are.
>> 
>> thanks,
>> m.
>> 
>> 
>> 
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