multiple collision detection (concave)

[Gaterman]

Hi,
My name is Gaetan i started tu use Newton Game Dynamics and loved what you did. I not very
familiar with it yet. When i wrote this i only have got to cube and sphere collision but convexhull
was not exacly what i was looking for, More like a concave collision. But i was thinking if it was possible
to have more than 1 shape to determine the collision, And more to the point that the seconde or third ect.. will
actualy cancel the collision.

Example a box collision could by cancelled by an other shape like a sphere half way in the box.

im using version 2.53 in a static library.
getting to 3.00 as soon as i compile properly the library.

did not read all of the board yet but did not find any thing that was close to what i was looking.

[Sweenie]

What your looking for is the Compound Collision.
It's a collider which can contain several subcolliders.
For example a compound collision for a chair could contain 6 subcolliders(boxes).
One for each leg, one for the seat and one for the back.

http://newtondynamics.com/wiki/index.ph ... s#Compound

[Gaterman]

thank you it is almost what a was looking for.
i think i can do more than one box two simulate a inner round corner. or 4 box instead of one for a hole in a box.

[Julio Jerez]

In core 300, if you run the SDK demo simple convex decomposition. you will see how there is a function that can decompose a complex shape into a compouse collison automatically.
the funtion is this:
NewtonMesh* const convexApproximation = NewtonMeshApproximateConvexDecomposition (newtonMesh, 0.01f, 0.2f, 32, 100, NULL);

you make a NewtonMesh and call that function, and it will mak eteh collsion shape for you.
In generat it does a very goo aproximation of the shape. runthe demo so that you can see.
This is only in core 300.

[Gaterman]

Thanks i think it what i need i will try it has soon as i have 3.0 compiling ok.