[SOLVED] gContactAddedCallback and btCollisionObjectWrapper

[Erasme Beck]

Hi everyone,
I'm having an issue with a tutorial using an older version of Bullet than mine (Bullet-2.82):
http://www.youtube.com/watch?v=YweNArzAHs4

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bool callbackFunc(btManifoldPoint& cp, const btCollisionObject* obj1, int id1, int index1, const btCollisionObject* obj2, int id2, int index2)
{
	std::cout << "First object: " << ((bulletObject*)obj1->getUserPointer())->id << std::endl;
	std::cout << "Second objetc: " << ((bulletObject*)obj2->getUserPointer())->id << std::endl;
	return false;
}

And in the main(), line 327:

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gContactAddedCallback = callbackFunc;

The error:

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invalid conversion from ‘bool (*)(btManifoldPoint&, const btCollisionObject*, int, int, const btCollisionObject*, int, int)’ to ‘ContactAddedCallback {aka bool (*)(btManifoldPoint&, const btCollisionObjectWrapper*, int, int, const btCollisionObjectWrapper*, int, int)}’ [-fpermissive]	opengl.cpp	/TestBullet	line 327

EDIT:

I changed

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bool callbackFunc(btManifoldPoint& cp, const btCollisionObject* obj1, int id1, int index1, const btCollisionObject* obj2, int id2, int index2)

to

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bool callbackFunc(btManifoldPoint& cp, const btCollisionObjectWrapper* obj1, int id1, int index1, const btCollisionObjectWrapper* obj2, int id2, int index2)

but getUserPointer is not a member of btCollisionObjectWrapper:

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‘const struct btCollisionObjectWrapper’ has no member named ‘getUserPointer’	opengl.cpp	/TestBullet	line 297

How can I fix this problem?
Thank you for your answer.

[bwelch]

I followed the same tutorial and ran into that problem. You have to change

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bool callbackFunc(btManifoldPoint& cp, const btCollisionObject* obj1, int id1, int index1, const btCollisionObject* obj2, int id2, int index2)

to

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bool callbackFunc(btManifoldPoint& cp, const btCollisionObjectWrapper* obj1, int id1, int index1, const btCollisionObjectWrapper* obj2, int id2, int index2)

I think that's the only change needed.

[Erasme Beck]

Thank you for your answer.
I did that change too.
But btCollisionObjectWrapper has no member called "getUserPointer"

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‘const struct btCollisionObjectWrapper’ has no member named ‘getUserPointer’	opengl.cpp	/TestBullet	line 296

btCollisionObjectWrapper is maybe not fully implemented.
But I'm too new to Bullet to be sure of this assumption.

[bwelch]

You have do do something like this:

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(bulletObject*)obj1->getCollisionObject()->getUserPointer()

[Erasme Beck]

You have do do something like this:

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(bulletObject*)obj1->getCollisionObject()->getUserPointer()

This worked!

Thank you bwelch!