bullet3-collision例子

bullet3的碰撞检测例子在examples/collision，CollisionTutorialBullet2类中，先是plCreateCollisionWorld，然后plCreateSphereShape，创建一些几何shape，然后调plCollide执行两个shape之间的碰撞检测，返回contact 点个数及坐标，调plWorldCollide执行world中所有shape的碰撞检测。
plXXX(...)这些函数是在CollisionSdkC_Api.h包装中的，都是间接调CollisionSdkInterface接口中的方法，sdk具体实现在internal目录中，实现了bullet2版本和bullet3版本，例如collide方法，bullet2中是，类和api前缀一般都是bt

int Bullet2CollisionSdk::collide(plCollisionWorldHandle worldHandle, plCollisionObjectHandle colA, plCollisionObjectHandle colB,
								 lwContactPoint* pointsOut, int pointCapacity)
{
	btCollisionWorld* world = (btCollisionWorld*)worldHandle;
	btCollisionObject* colObjA = (btCollisionObject*)colA;
	btCollisionObject* colObjB = (btCollisionObject*)colB;
	btAssert(world && colObjA && colObjB);
	if (world == m_internalData->m_collisionWorld && colObjA && colObjB)
	{
		Bullet2ContactResultCallback cb(pointsOut, pointCapacity);
		world->contactPairTest(colObjA, colObjB, cb);
		return cb.m_numContacts;
	}
	return 0;
}

bullet3中的实现，类前缀为b3

int RealTimeBullet3CollisionSdk::collide(plCollisionWorldHandle worldHandle, plCollisionObjectHandle colAHandle, plCollisionObjectHandle colBHandle,
										 lwContactPoint* pointsOutOrg, int pointCapacity)
{
	RTB3CollisionWorld* world = (RTB3CollisionWorld*)worldHandle;
	RTB3_ColliderOpaque2Int caster;
	caster.m_ptrValue = colAHandle;
	int colAIndex = caster.m_intValue;
	caster.m_ptrValue = colBHandle;
	int colBIndex = caster.m_intValue;
	const b3Collidable& colA = world->m_collidables[colAIndex];
	const b3Collidable& colB = world->m_collidables[colBIndex];

	plContactCache contactCache;
	contactCache.pointCapacity = pointCapacity;
	contactCache.pointsOut = pointsOutOrg;
	contactCache.numAddedPoints = 0;

	for (int i = 0; i < colA.m_numChildShapes; i++)
	{
		for (int j = 0; j < colB.m_numChildShapes; j++)
		{
			if (contactCache.numAddedPoints < pointCapacity)
			{
				//funcTbl_detectCollision[world->m_childShapes[colA.m_shapeIndex+i].m_shapeType]
				//					   [world->m_childShapes[colB.m_shapeIndex+j].m_shapeType](world,colAIndex,colA.m_shapeIndex+i,colBIndex,colB.m_shapeIndex+j,&contactCache);
			}
		}
		return contactCache.numAddedPoints;
	}

	return 0;
}