yade-users team mailing list archive

[Václav Šmilauer <eu@xxxxxxxx>]

Hi Jerome,

if I am reading the code right (yes, it is mine; "bzr qblame") , it will 
return the summary force using the same "convention" as is used for 
NormShearPhys::{normal,shear}Force; it does not care what is tension or 
compression. The (dot1<0.?1.:-1.) only determines the sense from id1 to 
id2 based on the normal, and normal is always from id1 to id2.

Cheers, Václav

> Hello,
>
> I'm considering the code in py/_utils.cpp for the function 
> forcesOnPlane, and i have few questions :
>
> - I'm guessing that there is an hidden convention of sign below the 
> orientation of the returned vector. Does this returned sum of forces 
> correspond to forces acting from one side of the plane to the other 
> (one "block" to the other) ?
> If yes (as I assume it), from which block to which one ? (with respect 
> to the normal defined in the call of the function ?)
>
> - And, if still yes to the first question, I imagine that it depends 
> on the convention assumed by the author of this code for 
> NormShearPhys->normalForce and NormShearPhys->shearForce : are these 
> vectors considered from body 1 to body 2 or the contrary ? I'm aware 
> of https://bugs.launchpad.net/yade/+bug/493102, but I think that the 
> guy who wrote this made a choice (Vaclav ?)
>
> Thanks,
>
> Jerome