TriangleCollisionShape appearing in wrong position.

PolyVox

04-03-2008 21:49:02

Hi, I am struggling with a very strange issue here which I think is a bug in OgreBullet (although I can't see it). I have three positions in space which I use as the three corners of a TriangleCollisionShape and also as the positions of three BoxCollisionShapes. Hence I would expect the boxes to lay at the corners of the triangles.

In reality the TriangleCollisionShape appears in a different position, apparently reflected in one (or more?) of the axis. The same problem occurs with TriangleMeshCollisionShape. As far as I can tell it is the boxes which are correct, though it is hard to be certain.

This is the code I use to construct the scene:



	const float      gDynamicBodyRestitution = 0.6f;

	const float      gDynamicBodyFriction    = 0.6f;

	const float      gDynamicBodyMass        = 1.0f;	



	Vector3 size(1.0,1.0,1.0);

	Vector3 pos1(10.0,0.0,0.0);

	Vector3 pos2(0.0,10.0,0.0);

	Vector3 pos3(0.0,0.0,10.0);

	

	//Init Bullet

	const Ogre::Vector3 gravityVector = Ogre::Vector3 (0,-2,0);

	const Ogre::AxisAlignedBox bounds = Ogre::AxisAlignedBox (Ogre::Vector3 (-10000, -10000, -10000),Ogre::Vector3 (10000,  10000,  10000));

	mWorld = new DynamicsWorld(mSceneMgr, bounds, gravityVector);



	//Add a cube

	Entity *box1 = mSceneMgr->createEntity("Box1","Bulletbox.mesh");

	box1->setMaterialName("Bullet/box");

	BoxCollisionShape *collisionShape1 = new BoxCollisionShape(size);

	RigidBody *rigidBody1 = new RigidBody("rigidBody1", mWorld);

	SceneNode *node1 = mSceneMgr->getRootSceneNode ()->createChildSceneNode ();

	node1->attachObject (box1);	

	rigidBody1->setShape (node1, collisionShape1, gDynamicBodyRestitution, gDynamicBodyFriction, 0.0, pos1, Quaternion(0,0,0,1));



	//Add a cube

	Entity *box2 = mSceneMgr->createEntity("Box2","Bulletbox.mesh");

	box2->setMaterialName("Bullet/box");

	BoxCollisionShape *collisionShape2 = new BoxCollisionShape(size);

	RigidBody *rigidBody2 = new RigidBody("rigidBody2", mWorld);

	SceneNode *node2 = mSceneMgr->getRootSceneNode ()->createChildSceneNode ();

	node2->attachObject (box2);

	rigidBody2->setShape (node2, collisionShape2, gDynamicBodyRestitution, gDynamicBodyFriction, 0.0, pos2, Quaternion(0,0,0,1));



	//Add a cube

	Entity *box3 = mSceneMgr->createEntity("Box3","Bulletbox.mesh");

	box2->setMaterialName("Bullet/box");

	BoxCollisionShape *collisionShape3 = new BoxCollisionShape(size);

	RigidBody *rigidBody3 = new RigidBody("rigidBody3", mWorld);

	SceneNode *node3 = mSceneMgr->getRootSceneNode ()->createChildSceneNode ();

	node3->attachObject (box3);

	rigidBody3->setShape (node3, collisionShape3, gDynamicBodyRestitution, gDynamicBodyFriction, 0.0, pos3, Quaternion(0,0,0,1));



	TriangleCollisionShape* groundCollisionShape = new TriangleCollisionShape(pos1,pos2,pos3);

	RigidBody *rigidBodyGround = new RigidBody("rigidBodyGround", mWorld);

	SceneNode *nodeGround = mSceneMgr->getRootSceneNode ()->createChildSceneNode ();

	rigidBodyGround->setShape (nodeGround,  groundCollisionShape, gDynamicBodyRestitution, gDynamicBodyFriction, 0.0, Vector3(0.0,0.0,0.0), Quaternion(0,0,0,1));

The result is as shown in the image below:

Any idea what going on? If it helps I can send my solution file, etc.

Thanks!