diff options
Diffstat (limited to 'extern/bullet2/src/BulletCollision/CollisionShapes/btCompoundShape.cpp')
-rw-r--r-- | extern/bullet2/src/BulletCollision/CollisionShapes/btCompoundShape.cpp | 100 |
1 files changed, 100 insertions, 0 deletions
diff --git a/extern/bullet2/src/BulletCollision/CollisionShapes/btCompoundShape.cpp b/extern/bullet2/src/BulletCollision/CollisionShapes/btCompoundShape.cpp new file mode 100644 index 00000000000..88ae8c7dfd4 --- /dev/null +++ b/extern/bullet2/src/BulletCollision/CollisionShapes/btCompoundShape.cpp @@ -0,0 +1,100 @@ +/* +Bullet Continuous Collision Detection and Physics Library +Copyright (c) 2003-2006 Erwin Coumans http://continuousphysics.com/Bullet/ + +This software is provided 'as-is', without any express or implied warranty. +In no event will the authors be held liable for any damages arising from the use of this software. +Permission is granted to anyone to use this software for any purpose, +including commercial applications, and to alter it and redistribute it freely, +subject to the following restrictions: + +1. The origin of this software must not be misrepresented; you must not claim that you wrote the original software. If you use this software in a product, an acknowledgment in the product documentation would be appreciated but is not required. +2. Altered source versions must be plainly marked as such, and must not be misrepresented as being the original software. +3. This notice may not be removed or altered from any source distribution. +*/ + +#include "btCompoundShape.h" + + +#include "btCollisionShape.h" + + +btCompoundShape::btCompoundShape() +:m_localAabbMin(1e30f,1e30f,1e30f), +m_localAabbMax(-1e30f,-1e30f,-1e30f), +m_aabbTree(0), +m_collisionMargin(0.f), +m_localScaling(1.f,1.f,1.f) +{ +} + + +btCompoundShape::~btCompoundShape() +{ +} + +void btCompoundShape::addChildShape(const btTransform& localTransform,btCollisionShape* shape) +{ + m_childTransforms.push_back(localTransform); + m_childShapes.push_back(shape); + + //extend the local aabbMin/aabbMax + btVector3 localAabbMin,localAabbMax; + shape->getAabb(localTransform,localAabbMin,localAabbMax); + for (int i=0;i<3;i++) + { + if (m_localAabbMin[i] > localAabbMin[i]) + { + m_localAabbMin[i] = localAabbMin[i]; + } + if (m_localAabbMax[i] < localAabbMax[i]) + { + m_localAabbMax[i] = localAabbMax[i]; + } + + } +} + + + + ///getAabb's default implementation is brute force, expected derived classes to implement a fast dedicated version +void btCompoundShape::getAabb(const btTransform& trans,btVector3& aabbMin,btVector3& aabbMax) const +{ + btVector3 localHalfExtents = 0.5f*(m_localAabbMax-m_localAabbMin); + btVector3 localCenter = 0.5f*(m_localAabbMax+m_localAabbMin); + + btMatrix3x3 abs_b = trans.getBasis().absolute(); + + btPoint3 center = trans(localCenter); + + btVector3 extent = btVector3(abs_b[0].dot(localHalfExtents), + abs_b[1].dot(localHalfExtents), + abs_b[2].dot(localHalfExtents)); + extent += btVector3(getMargin(),getMargin(),getMargin()); + + aabbMin = center - extent; + aabbMax = center + extent; +} + +void btCompoundShape::calculateLocalInertia(btScalar mass,btVector3& inertia) +{ + //approximation: take the inertia from the aabb for now + btTransform ident; + ident.setIdentity(); + btVector3 aabbMin,aabbMax; + getAabb(ident,aabbMin,aabbMax); + + btVector3 halfExtents = (aabbMax-aabbMin)*0.5f; + + btScalar lx=2.f*(halfExtents.x()); + btScalar ly=2.f*(halfExtents.y()); + btScalar lz=2.f*(halfExtents.z()); + + inertia[0] = mass/(12.0f) * (ly*ly + lz*lz); + inertia[1] = mass/(12.0f) * (lx*lx + lz*lz); + inertia[2] = mass/(12.0f) * (lx*lx + ly*ly); + +} + + + |