[Solved] raycasting bullet vehicle

[johnsonalpha]

Wow ive been searching for hours can someone please help me with a simple convex hull ive looked at ConvexDecompositionDemo i dont understand it Please Help!!!


What am i doing wrong here?

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btVector3 motstate(0, 0, 0);

btVector3 inertia(0, 0, 0);

// create a vertex cloud defining a square-based pyramid
btVector3 points[5] = { btVector3(-0.5,1,1), btVector3(-0.5,1,-1), btVector3(-0.5,-1,1), btVector3(-0.5,-1,-1), btVector3(1,0,0) };
	

[b]how do i add this to the dynamics world???[/b]

Also how does the add point method work? ===============================================

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btVector3 motstate(0, 0, 0);

btVector3 inertia(0, 0, 0);

// create a vertex cloud defining a square-based pyramid
btVector3 points[5] = { btVector3(-0.5,1,1), btVector3(-0.5,1,-1), btVector3(-0.5,-1,1), btVector3(-0.5,-1,-1), btVector3(1,0,0) };



WHERE DO I GO FROM HERE?
how do i add the points i just add to a convex hull?

[drleviathan]

To create a btConvexHull shape you would do something like this:

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    int NUM_POINTS = 5;
    btVector3 points[NUM_POINTS] = { 
        btVector3(-0.5, 1,  1),
        btVector3(-0.5, 1, -1),
        btVector3(-0.5,-1,  1),
        btVector3(-0.5,-1, -1), 
        btVector3(   1, 0,  0) };

    btConvexHullShape* shape = new btConvexHullShape();
    for (int i = 0; i < NUM_POINTS; ++i) {
        // passing 'false' as second argument is an optimization that avoids constantly calling 
        // recalcLocalAabb(), which can then be called once after all points are added.
        shape->addPoint(points[i], false);
    }           
    shape->recalcLocalAabb();

To use the shape on a btRigidBody:

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    // assuming you've computed mass, inertia, and have a pointer to a MotionState:
    body = new btRigidBody(mass, motionState, shape, inertia);
    dynamicsWorld->addBody(body);

[johnsonalpha]

Is dynamicsWorld->addBody(body) the same as dynamicsWorld->addRigidBody(body)?

[aviator]

Is dynamicsWorld->addBody(body) the same as dynamicsWorld->addRigidBody(body)?

Ohh man you really need to learn Bullet more
He meant dynamicsWorld->addRigidBody(rBody).

[drleviathan]

Yes sorry, that was a typo. Use dynamicsEngine->addRigidBody(body);

[ed_welch]

by the way, 2 things about btConvexHullShape:
1) don't use addPoint if you have more than a few points. It is incredably slow.
2) you will also probaly need to use btShapeHull for performance, if you are using models with more than a few dozen triangles

[johnsonalpha]

How would i do that?

[ed_welch]

How would i do that?

This is the code I use:

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    btConvexHullShape convexHullShape(
        m_pPositions->GetVertexData(), m_pPositions->GetNumVertices(), m_pPositions->GetStride()*sizeof(float));
    //create a hull approximation
	btShapeHull* hull = new btShapeHull(&convexHullShape);
	btScalar margin = convexHullShape.getMargin();
	hull->buildHull(margin);

[johnsonalpha]

Thats all O_o?