Some troubles with sleeping and size of collision primitives

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Hi.
When i tried to migrate from newton version 1.xx to version 2.24, i get some problems.

1. there is problem with new sleeping functions.
Older version has function to unfreeze bodies, but new version have not this.
problem is appeared when i use NewtonBodySetMatrix. when i call it, it is don`t unfreeze bodies.
i need to set position of the body by call this function. in old version after call of NewtonBodySetMatrix function, i call NewtonWorldUnfreezeBody and it works fine. How can i awake a body after call of NewtonBodySetMatrix function?

2. when i use funcion like NewtonCreateBox with the size of primitive not equal to (1, 1, 1) and create body from it, or set it to body by calling NewtonBodySetCollision, i have some troubles. real body size it seems not the same as i want, and sometimes, body do some amazing tricks... like penetration in other bodies, or rotating too fast, when i set it position.
in older version it works fine.

[Julio Jerez]

check out the wiki tutorials

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here is video & wrapper sources, _old - is version 1.xx
http://disk.tom.ru/ymnwn8w/1/0ad9e/Newton.rar

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i think the bug is here.
i use NewtonBodyGetAABB to draw bbox of each body.
in version 153 it works perfect. when i try to do it in 224, i have been surprized.
i think, the reason is in bbox margin, it does not work properly.
just look at video > http://disk.tom.ru/r4hdevj

[Julio Jerez]

you must have a different bug NewtonBodyGetAABB, has being working for a long time.

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i cant understand, where is bug in my code. i do all the things as i do in old version(153).

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ok, f..g scale. it works. one more problem to fix.. with sleeping..

[Julio Jerez]

what does f--g scale means?

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when i use version, 153 i pass scaled matrix in NewtonBodySetMatrix, and it work properly - scale does not affect to collision object of a body.
but in 224 it cause some bugs with collision objects & calculating AABB.

[Julio Jerez]

neither 1.53 or 2.xx support scale in the body matrix of colliiosn offsset.

what you did workd in 1.53 because 1.53 was normalizing teh matrix when you call ste matrix.
but that break determinism with using newton in network, so it had to be removed

you should no pass matrix with scales.

if you are using 2.xx you can use teh dMatrix class to remove teh scale form a matrix

Code: Select all

dMatrix matrixWithScale;
dMatrix transformMatrix;
dVector scale;
dMatrix stretchAxis;
matrixWithScale.PolarDecomposition (transformMatrix, scale, stretchAxis);

//then use transformMatrix to set the body matrix

[ledahut]

About freeze.
In Newton2 use: NewtonBodySetFreezeState and NewtonBodyGetFreezeState
The wiki is not up to date about freeze functions.

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you should no pass matrix with scales.

i do it my own way - i have function to normalize matrices:

Code: Select all

void Matrix::normalize() {
   Vector x(data[0][0],data[0][1],data[0][2]);
   Vector y(data[1][0],data[1][1],data[1][2]);
   Vector z;
   x.normalize();
   z = cross(x,y);
   z.normalize();
   y = cross(z,x);
   y.normalize();
   data[0][0] = x.x; data[1][0] = y.x; data[2][0] = z.x;
   data[0][1] = x.y; data[1][1] = y.y; data[2][1] = z.y;
   data[0][2] = x.z; data[1][2] = y.z; data[2][2] = z.z;
}


About freeze.In Newton2 use: NewtonBodySetFreezeState and NewtonBodyGetFreezeStateThe wiki is not up to date about freeze functions.

i attempt to try this functions, but it is not to awake frozen bodies.
i need function like NewtonWorldUnfreezeBody, wich is in version153.

[ledahut]

How you body become frozen? You call a function? When you create them? Or when they reach equilibrium [body is sleeping] ?
Be careful freeze and sleep is not the same thing. See NewtonBodySetAutoSleep.

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How you body become frozen? You call a function? When you create them? Or when they reach equilibrium [body is sleeping] ?
Be careful freeze and sleep is not the same thing. See NewtonBodySetAutoSleep.

when i create body, i set NewtonBodySetAutoSleep to true and i use NewtonBodyGetSleepState to determine sleeping state. when body is go to sleep when equilibrium becomes reaced, i cannot to awake body by setting its matrix. when i call other functions, like NewtonBodySetVelocity, body becomes awaken.
it seems, body do not call private function like NewtonWorldUnfreezeBody when sleeping state is reaced.

[Stucuk]

If your not going to give it any force/velocity then whats the point of waking it up? The point of sleep is so that objects that arn't moving enough won't have calculations done on them. Setting the matrix doesn't give the body any force/velocity so its not going to be moving.