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Diffstat (limited to 'thirdparty/bullet/BulletCollision/CollisionShapes/btCompoundShape.cpp')
-rw-r--r-- | thirdparty/bullet/BulletCollision/CollisionShapes/btCompoundShape.cpp | 359 |
1 files changed, 359 insertions, 0 deletions
diff --git a/thirdparty/bullet/BulletCollision/CollisionShapes/btCompoundShape.cpp b/thirdparty/bullet/BulletCollision/CollisionShapes/btCompoundShape.cpp new file mode 100644 index 0000000000..e8c8c336cd --- /dev/null +++ b/thirdparty/bullet/BulletCollision/CollisionShapes/btCompoundShape.cpp @@ -0,0 +1,359 @@ +/* +Bullet Continuous Collision Detection and Physics Library +Copyright (c) 2003-2009 Erwin Coumans http://bulletphysics.org + +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" +#include "BulletCollision/BroadphaseCollision/btDbvt.h" +#include "LinearMath/btSerializer.h" + +btCompoundShape::btCompoundShape(bool enableDynamicAabbTree, const int initialChildCapacity) +: m_localAabbMin(btScalar(BT_LARGE_FLOAT),btScalar(BT_LARGE_FLOAT),btScalar(BT_LARGE_FLOAT)), +m_localAabbMax(btScalar(-BT_LARGE_FLOAT),btScalar(-BT_LARGE_FLOAT),btScalar(-BT_LARGE_FLOAT)), +m_dynamicAabbTree(0), +m_updateRevision(1), +m_collisionMargin(btScalar(0.)), +m_localScaling(btScalar(1.),btScalar(1.),btScalar(1.)) +{ + m_shapeType = COMPOUND_SHAPE_PROXYTYPE; + + if (enableDynamicAabbTree) + { + void* mem = btAlignedAlloc(sizeof(btDbvt),16); + m_dynamicAabbTree = new(mem) btDbvt(); + btAssert(mem==m_dynamicAabbTree); + } + + m_children.reserve(initialChildCapacity); +} + + +btCompoundShape::~btCompoundShape() +{ + if (m_dynamicAabbTree) + { + m_dynamicAabbTree->~btDbvt(); + btAlignedFree(m_dynamicAabbTree); + } +} + +void btCompoundShape::addChildShape(const btTransform& localTransform,btCollisionShape* shape) +{ + m_updateRevision++; + //m_childTransforms.push_back(localTransform); + //m_childShapes.push_back(shape); + btCompoundShapeChild child; + child.m_node = 0; + child.m_transform = localTransform; + child.m_childShape = shape; + child.m_childShapeType = shape->getShapeType(); + child.m_childMargin = shape->getMargin(); + + + //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]; + } + + } + if (m_dynamicAabbTree) + { + const btDbvtVolume bounds=btDbvtVolume::FromMM(localAabbMin,localAabbMax); + size_t index = m_children.size(); + child.m_node = m_dynamicAabbTree->insert(bounds,reinterpret_cast<void*>(index) ); + } + + m_children.push_back(child); + +} + +void btCompoundShape::updateChildTransform(int childIndex, const btTransform& newChildTransform,bool shouldRecalculateLocalAabb) +{ + m_children[childIndex].m_transform = newChildTransform; + + if (m_dynamicAabbTree) + { + ///update the dynamic aabb tree + btVector3 localAabbMin,localAabbMax; + m_children[childIndex].m_childShape->getAabb(newChildTransform,localAabbMin,localAabbMax); + ATTRIBUTE_ALIGNED16(btDbvtVolume) bounds=btDbvtVolume::FromMM(localAabbMin,localAabbMax); + //int index = m_children.size()-1; + m_dynamicAabbTree->update(m_children[childIndex].m_node,bounds); + } + + if (shouldRecalculateLocalAabb) + { + recalculateLocalAabb(); + } +} + +void btCompoundShape::removeChildShapeByIndex(int childShapeIndex) +{ + m_updateRevision++; + btAssert(childShapeIndex >=0 && childShapeIndex < m_children.size()); + if (m_dynamicAabbTree) + { + m_dynamicAabbTree->remove(m_children[childShapeIndex].m_node); + } + m_children.swap(childShapeIndex,m_children.size()-1); + if (m_dynamicAabbTree) + m_children[childShapeIndex].m_node->dataAsInt = childShapeIndex; + m_children.pop_back(); + +} + + + +void btCompoundShape::removeChildShape(btCollisionShape* shape) +{ + m_updateRevision++; + // Find the children containing the shape specified, and remove those children. + //note: there might be multiple children using the same shape! + for(int i = m_children.size()-1; i >= 0 ; i--) + { + if(m_children[i].m_childShape == shape) + { + removeChildShapeByIndex(i); + } + } + + + + recalculateLocalAabb(); +} + +void btCompoundShape::recalculateLocalAabb() +{ + // Recalculate the local aabb + // Brute force, it iterates over all the shapes left. + + m_localAabbMin = btVector3(btScalar(BT_LARGE_FLOAT),btScalar(BT_LARGE_FLOAT),btScalar(BT_LARGE_FLOAT)); + m_localAabbMax = btVector3(btScalar(-BT_LARGE_FLOAT),btScalar(-BT_LARGE_FLOAT),btScalar(-BT_LARGE_FLOAT)); + + //extend the local aabbMin/aabbMax + for (int j = 0; j < m_children.size(); j++) + { + btVector3 localAabbMin,localAabbMax; + m_children[j].m_childShape->getAabb(m_children[j].m_transform, 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 = btScalar(0.5)*(m_localAabbMax-m_localAabbMin); + btVector3 localCenter = btScalar(0.5)*(m_localAabbMax+m_localAabbMin); + + //avoid an illegal AABB when there are no children + if (!m_children.size()) + { + localHalfExtents.setValue(0,0,0); + localCenter.setValue(0,0,0); + } + localHalfExtents += btVector3(getMargin(),getMargin(),getMargin()); + + + btMatrix3x3 abs_b = trans.getBasis().absolute(); + + btVector3 center = trans(localCenter); + + btVector3 extent = localHalfExtents.dot3(abs_b[0], abs_b[1], abs_b[2]); + aabbMin = center-extent; + aabbMax = center+extent; + +} + +void btCompoundShape::calculateLocalInertia(btScalar mass,btVector3& inertia) const +{ + //approximation: take the inertia from the aabb for now + btTransform ident; + ident.setIdentity(); + btVector3 aabbMin,aabbMax; + getAabb(ident,aabbMin,aabbMax); + + btVector3 halfExtents = (aabbMax-aabbMin)*btScalar(0.5); + + btScalar lx=btScalar(2.)*(halfExtents.x()); + btScalar ly=btScalar(2.)*(halfExtents.y()); + btScalar lz=btScalar(2.)*(halfExtents.z()); + + inertia[0] = mass/(btScalar(12.0)) * (ly*ly + lz*lz); + inertia[1] = mass/(btScalar(12.0)) * (lx*lx + lz*lz); + inertia[2] = mass/(btScalar(12.0)) * (lx*lx + ly*ly); + +} + + + + +void btCompoundShape::calculatePrincipalAxisTransform(btScalar* masses, btTransform& principal, btVector3& inertia) const +{ + int n = m_children.size(); + + btScalar totalMass = 0; + btVector3 center(0, 0, 0); + int k; + + for (k = 0; k < n; k++) + { + btAssert(masses[k]>0); + center += m_children[k].m_transform.getOrigin() * masses[k]; + totalMass += masses[k]; + } + + btAssert(totalMass>0); + + center /= totalMass; + principal.setOrigin(center); + + btMatrix3x3 tensor(0, 0, 0, 0, 0, 0, 0, 0, 0); + for ( k = 0; k < n; k++) + { + btVector3 i; + m_children[k].m_childShape->calculateLocalInertia(masses[k], i); + + const btTransform& t = m_children[k].m_transform; + btVector3 o = t.getOrigin() - center; + + //compute inertia tensor in coordinate system of compound shape + btMatrix3x3 j = t.getBasis().transpose(); + j[0] *= i[0]; + j[1] *= i[1]; + j[2] *= i[2]; + j = t.getBasis() * j; + + //add inertia tensor + tensor[0] += j[0]; + tensor[1] += j[1]; + tensor[2] += j[2]; + + //compute inertia tensor of pointmass at o + btScalar o2 = o.length2(); + j[0].setValue(o2, 0, 0); + j[1].setValue(0, o2, 0); + j[2].setValue(0, 0, o2); + j[0] += o * -o.x(); + j[1] += o * -o.y(); + j[2] += o * -o.z(); + + //add inertia tensor of pointmass + tensor[0] += masses[k] * j[0]; + tensor[1] += masses[k] * j[1]; + tensor[2] += masses[k] * j[2]; + } + + tensor.diagonalize(principal.getBasis(), btScalar(0.00001), 20); + inertia.setValue(tensor[0][0], tensor[1][1], tensor[2][2]); +} + + + + + +void btCompoundShape::setLocalScaling(const btVector3& scaling) +{ + + for(int i = 0; i < m_children.size(); i++) + { + btTransform childTrans = getChildTransform(i); + btVector3 childScale = m_children[i].m_childShape->getLocalScaling(); +// childScale = childScale * (childTrans.getBasis() * scaling); + childScale = childScale * scaling / m_localScaling; + m_children[i].m_childShape->setLocalScaling(childScale); + childTrans.setOrigin((childTrans.getOrigin()) * scaling / m_localScaling); + updateChildTransform(i, childTrans,false); + } + + m_localScaling = scaling; + recalculateLocalAabb(); + +} + + +void btCompoundShape::createAabbTreeFromChildren() +{ + if ( !m_dynamicAabbTree ) + { + void* mem = btAlignedAlloc(sizeof(btDbvt),16); + m_dynamicAabbTree = new(mem) btDbvt(); + btAssert(mem==m_dynamicAabbTree); + + for ( int index = 0; index < m_children.size(); index++ ) + { + btCompoundShapeChild &child = m_children[index]; + + //extend the local aabbMin/aabbMax + btVector3 localAabbMin,localAabbMax; + child.m_childShape->getAabb(child.m_transform,localAabbMin,localAabbMax); + + const btDbvtVolume bounds=btDbvtVolume::FromMM(localAabbMin,localAabbMax); + size_t index2 = index; + child.m_node = m_dynamicAabbTree->insert(bounds, reinterpret_cast<void*>(index2) ); + } + } +} + + +///fills the dataBuffer and returns the struct name (and 0 on failure) +const char* btCompoundShape::serialize(void* dataBuffer, btSerializer* serializer) const +{ + + btCompoundShapeData* shapeData = (btCompoundShapeData*) dataBuffer; + btCollisionShape::serialize(&shapeData->m_collisionShapeData, serializer); + + shapeData->m_collisionMargin = float(m_collisionMargin); + shapeData->m_numChildShapes = m_children.size(); + shapeData->m_childShapePtr = 0; + if (shapeData->m_numChildShapes) + { + btChunk* chunk = serializer->allocate(sizeof(btCompoundShapeChildData),shapeData->m_numChildShapes); + btCompoundShapeChildData* memPtr = (btCompoundShapeChildData*)chunk->m_oldPtr; + shapeData->m_childShapePtr = (btCompoundShapeChildData*)serializer->getUniquePointer(memPtr); + + for (int i=0;i<shapeData->m_numChildShapes;i++,memPtr++) + { + memPtr->m_childMargin = float(m_children[i].m_childMargin); + memPtr->m_childShape = (btCollisionShapeData*)serializer->getUniquePointer(m_children[i].m_childShape); + //don't serialize shapes that already have been serialized + if (!serializer->findPointer(m_children[i].m_childShape)) + { + btChunk* chunk = serializer->allocate(m_children[i].m_childShape->calculateSerializeBufferSize(),1); + const char* structType = m_children[i].m_childShape->serialize(chunk->m_oldPtr,serializer); + serializer->finalizeChunk(chunk,structType,BT_SHAPE_CODE,m_children[i].m_childShape); + } + + memPtr->m_childShapeType = m_children[i].m_childShapeType; + m_children[i].m_transform.serializeFloat(memPtr->m_transform); + } + serializer->finalizeChunk(chunk,"btCompoundShapeChildData",BT_ARRAY_CODE,chunk->m_oldPtr); + } + return "btCompoundShapeData"; +} + |