yade-dev team mailing list archive
-
yade-dev team
-
Mailing list archive
-
Message #12184
[Bug 1474956] Re: Clump::updateProperties discretization not defined robustly
>it should be downward compatible
Sure of that? It makes things more complex without adding any additional flexibility.
As far as inertia matters, there is no point in subdiscretizing this tiny sphere which is 1000 times smaller that the clump.
But if you really want to do it you can: discretization=10000.
It is not possible the other way around since discretization can't be less than 1 (as explained above).
What is the advantage of defining resolution wrt the smallest element of an object overall?
I agree that downward compatibility is good when possible, but we can't
keep it at all prices. Sometimes we have to keep things simple to.
>it needs a lot of extra code modification
Without the above optional behavior the fix fits in 3 changed lines (and
one change is in fact unrelated, see below).
Thanks for pointing to the relevant doc section.
Bruno
p.s. Please don't cc me or anybody else when sending email to
bug/aswers/lists because it generates duplicates
diff --git a/core/Clump.cpp b/core/Clump.cpp
index deb10b5..869cc5a 100644
--- a/core/Clump.cpp
+++ b/core/Clump.cpp
@@ -144,17 +144,18 @@ void Clump::updateProperties(const shared_ptr<Body>& clumpBody, unsigned int dis
*/
if(intersecting){
- //get boundaries and minimum radius of clump:
- Real rMin=1./0.; AlignedBox3r aabb;
+ //get boundaries of clump:
+ AlignedBox3r aabb;
FOREACH(MemberMap::value_type& mm, clump->members){
const shared_ptr<Body> subBody = Body::byId(mm.first);
if (subBody->shape->getClassIndex() == Sph_Index){//clump member should be a sphere
const Sphere* sphere = YADE_CAST<Sphere*> (subBody->shape.get());
aabb.extend(subBody->state->pos + Vector3r::Constant(sphere->radius));
aabb.extend(subBody->state->pos - Vector3r::Constant(sphere->radius));
- rMin=min(rMin,sphere->radius);
}
}
+ Real rMin=min(aabb.diagonal()[0],min(aabb.diagonal()[1],aabb.diagonal()[2]));
+
//get volume and inertia tensor using regular cubic cell array inside bounding box of the clump:
Real dx = rMin/discretization; //edge length of cell
Real dv = pow(dx,3); //volume of cell
@@ -182,8 +183,7 @@ void Clump::updateProperties(const shared_ptr<Body>& clumpBody, unsigned int dis
}
}
}
- }
- if(!intersecting){
+ } else {//not intersecting
FOREACH(MemberMap::value_type& mm, clump->members){
// mm.first is Body::id_t, mm.second is Se3r of that body
const shared_ptr<Body> subBody=Body::byId(mm.first);
--
You received this bug notification because you are a member of Yade
developers, which is subscribed to Yade.
https://bugs.launchpad.net/bugs/1474956
Title:
Clump::updateProperties discretization not defined robustly
Status in Yade:
Confirmed
Bug description:
Most likely the reason for performance drop reported in [1]
dx in the voxel decomposition is minRad/discretization.
The problem is when a sphere of radius 1 is member of a clump which aabb has the size 1000 (for instance).
Using the minimal discretization=1 gives a number of voxel = 1e9 in such case and it is no possible to go below this number.
I think discretization should refer to aabb size, not member size. I have this fixed locally, let me know if you agree with the fix.
[1] https://answers.launchpad.net/yade/+question/268954
To manage notifications about this bug go to:
https://bugs.launchpad.net/yade/+bug/1474956/+subscriptions
References
