How to make static rigid body solid.

[ivopeterka]

Can anybody help me with following problem?

I'm completely new to Bullet and I'm trying to accomplish some task in it, which as its part has horizontal movement of one object on top of another. I created little example, where I first let fall small box

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	btTransform Transform2;
	Transform2.setIdentity();
	btVector3 position = btVector3(0,10,0);
	Transform2.setOrigin(position);
	btDefaultMotionState *MS2 = new btDefaultMotionState(Transform2);
	btCollisionShape *CS2 = new btBoxShape(btVector3(0.5,0.5,0.5));
	btVector3 LocalInertia2;
	CS2->calculateLocalInertia(1,LocalInertia2);
	btRigidBody *RB2 = new btRigidBody(1, MS2, CS2, LocalInertia2);

on a platform (static rigid body)

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	btTransform Transform1;
	Transform1.setIdentity();
	Transform1.setOrigin(btVector3(0,0,0));
	btDefaultMotionState *MS1 = new btDefaultMotionState(Transform1);
	btCollisionShape *CS1 = new btBoxShape(btVector3(5,0.5,5));
	btVector3 LocalInertia1;
	CS1->calculateLocalInertia(1.0,LocalInertia1);
	btRigidBody* RB1 = new btRigidBody(0, MS1, CS1, LocalInertia1);

I want to then slide the box on top of the platform. So I added Central Impulse (I ensured, that it is applied some time after the box fells on the platform). It comes as this:

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if(currTime - origTime > 3000 && !bForced)
{
	RB2->applyCentralImpulse(btVector3(0.1f,0,0.1f));
	bForced = true;
}

The problem is, that after applying impulse (and I tried also something like this with applyForce) the box albeit starts to move to the side, however it also starts to sink into the platform.

Is there any way how to make the platform solid (as a stone), so the box doesn't sink into it?

The Bullet world I'm using is initialized as follows

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btDefaultCollisionConfiguration *CollisionConfiguration = new btDefaultCollisionConfiguration();
btBroadphaseInterface *BroadPhase = new btAxisSweep3(btVector3(-1000, -1000, -1000), btVector3(1000, 1000, 1000));
btCollisionDispatcher *Dispatcher = new btCollisionDispatcher(CollisionConfiguration);
btSequentialImpulseConstraintSolver *Solver = new btSequentialImpulseConstraintSolver();
btDiscreteDynamicsWorld *World = new btDiscreteDynamicsWorld(Dispatcher, BroadPhase, Solver, CollisionConfiguration);

Thanks in advance for any advice.

[ivopeterka]

Well, some time ago I found it. The problem was

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CS1->calculateLocalInertia(1.0,LocalInertia1);

as it should be

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CS1->calculateLocalInertia(0,LocalInertia1);

for the platform. Simply in one of the two places, where mass is defined, I used 1 in place of 0 by mistake ... .

[Dr.Shepherd]

Well, some time ago I found it. The problem was

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CS1->calculateLocalInertia(1.0,LocalInertia1);

as it should be

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CS1->calculateLocalInertia(0,LocalInertia1);

for the platform. Simply in one of the two places, where mass is defined, I used 1 in place of 0 by mistake ... .

ok, so you set the platform to be a dynamic object as well, is it?