reactphysics3d/src/collision/broadphase/BroadPhaseAlgorithm.cpp

358 lines
16 KiB
C++

/********************************************************************************
* ReactPhysics3D physics library, http://www.reactphysics3d.com *
* Copyright (c) 2010-2016 Daniel Chappuis *
*********************************************************************************
* *
* 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. *
* *
********************************************************************************/
// Libraries
#include "BroadPhaseAlgorithm.h"
#include "collision/CollisionDetection.h"
#include "engine/Profiler.h"
// We want to use the ReactPhysics3D namespace
using namespace reactphysics3d;
// Constructor
BroadPhaseAlgorithm::BroadPhaseAlgorithm(CollisionDetection& collisionDetection)
:mDynamicAABBTree(collisionDetection.getMemoryManager().getPoolAllocator(), DYNAMIC_TREE_AABB_GAP),
mNbMovedShapes(0), mNbAllocatedMovedShapes(8),
mNbNonUsedMovedShapes(0), mNbPotentialPairs(0), mNbAllocatedPotentialPairs(8),
mCollisionDetection(collisionDetection) {
PoolAllocator& poolAllocator = collisionDetection.getMemoryManager().getPoolAllocator();
// Allocate memory for the array of non-static proxy shapes IDs
mMovedShapes = static_cast<int*>(poolAllocator.allocate(mNbAllocatedMovedShapes * sizeof(int)));
assert(mMovedShapes != nullptr);
// Allocate memory for the array of potential overlapping pairs
mPotentialPairs = static_cast<BroadPhasePair*>(poolAllocator.allocate(mNbAllocatedPotentialPairs * sizeof(BroadPhasePair)));
assert(mPotentialPairs != nullptr);
#ifdef IS_PROFILING_ACTIVE
mProfiler = nullptr;
#endif
}
// Destructor
BroadPhaseAlgorithm::~BroadPhaseAlgorithm() {
// Get the memory pool allocatory
PoolAllocator& poolAllocator = mCollisionDetection.getMemoryManager().getPoolAllocator();
// Release the memory for the array of non-static proxy shapes IDs
poolAllocator.release(mMovedShapes, mNbAllocatedMovedShapes * sizeof (int));
// Release the memory for the array of potential overlapping pairs
poolAllocator.release(mPotentialPairs, mNbAllocatedPotentialPairs * sizeof(BroadPhasePair));
}
// Add a collision shape in the array of shapes that have moved in the last simulation step
// and that need to be tested again for broad-phase overlapping.
void BroadPhaseAlgorithm::addMovedCollisionShape(int broadPhaseID) {
// Allocate more elements in the array of shapes that have moved if necessary
if (mNbAllocatedMovedShapes == mNbMovedShapes) {
// Get the memory pool allocatory
PoolAllocator& poolAllocator = mCollisionDetection.getMemoryManager().getPoolAllocator();
uint oldNbAllocatedMovedShapes = mNbAllocatedMovedShapes;
mNbAllocatedMovedShapes *= 2;
int* oldArray = mMovedShapes;
mMovedShapes = static_cast<int*>(poolAllocator.allocate(mNbAllocatedMovedShapes * sizeof(int)));
assert(mMovedShapes != nullptr);
std::memcpy(mMovedShapes, oldArray, mNbMovedShapes * sizeof(int));
poolAllocator.release(oldArray, oldNbAllocatedMovedShapes * sizeof(int));
}
// Store the broad-phase ID into the array of shapes that have moved
assert(mNbMovedShapes < mNbAllocatedMovedShapes);
assert(mMovedShapes != nullptr);
mMovedShapes[mNbMovedShapes] = broadPhaseID;
mNbMovedShapes++;
}
// Remove a collision shape from the array of shapes that have moved in the last simulation step
// and that need to be tested again for broad-phase overlapping.
void BroadPhaseAlgorithm::removeMovedCollisionShape(int broadPhaseID) {
assert(mNbNonUsedMovedShapes <= mNbMovedShapes);
// If less than the quarter of allocated elements of the non-static shapes IDs array
// are used, we release some allocated memory
if ((mNbMovedShapes - mNbNonUsedMovedShapes) < mNbAllocatedMovedShapes / 4 &&
mNbAllocatedMovedShapes > 8) {
// Get the memory pool allocatory
PoolAllocator& poolAllocator = mCollisionDetection.getMemoryManager().getPoolAllocator();
uint oldNbAllocatedMovedShapes = mNbAllocatedMovedShapes;
mNbAllocatedMovedShapes /= 2;
int* oldArray = mMovedShapes;
mMovedShapes = static_cast<int*>(poolAllocator.allocate(mNbAllocatedMovedShapes * sizeof(int)));
assert(mMovedShapes != nullptr);
uint nbElements = 0;
for (uint i=0; i<mNbMovedShapes; i++) {
if (oldArray[i] != -1) {
mMovedShapes[nbElements] = oldArray[i];
nbElements++;
}
}
mNbMovedShapes = nbElements;
mNbNonUsedMovedShapes = 0;
poolAllocator.release(oldArray, oldNbAllocatedMovedShapes * sizeof(int));
}
// Remove the broad-phase ID from the array
for (uint i=0; i<mNbMovedShapes; i++) {
if (mMovedShapes[i] == broadPhaseID) {
mMovedShapes[i] = -1;
mNbNonUsedMovedShapes++;
break;
}
}
}
// Add a proxy collision shape into the broad-phase collision detection
void BroadPhaseAlgorithm::addProxyCollisionShape(ProxyShape* proxyShape, const AABB& aabb) {
assert(proxyShape->mBroadPhaseID == -1);
// Add the collision shape into the dynamic AABB tree and get its broad-phase ID
int nodeId = mDynamicAABBTree.addObject(aabb, proxyShape);
// Set the broad-phase ID of the proxy shape
proxyShape->mBroadPhaseID = nodeId;
// Add the collision shape into the array of bodies that have moved (or have been created)
// during the last simulation step
addMovedCollisionShape(proxyShape->mBroadPhaseID);
}
// Remove a proxy collision shape from the broad-phase collision detection
void BroadPhaseAlgorithm::removeProxyCollisionShape(ProxyShape* proxyShape) {
assert(proxyShape->mBroadPhaseID != -1);
int broadPhaseID = proxyShape->mBroadPhaseID;
proxyShape->mBroadPhaseID = -1;
// Remove the collision shape from the dynamic AABB tree
mDynamicAABBTree.removeObject(broadPhaseID);
// Remove the collision shape into the array of shapes that have moved (or have been created)
// during the last simulation step
removeMovedCollisionShape(broadPhaseID);
}
// Notify the broad-phase that a collision shape has moved and need to be updated
void BroadPhaseAlgorithm::updateProxyCollisionShape(ProxyShape* proxyShape, const AABB& aabb,
const Vector3& displacement, bool forceReinsert) {
int broadPhaseID = proxyShape->mBroadPhaseID;
assert(broadPhaseID >= 0);
// Update the dynamic AABB tree according to the movement of the collision shape
bool hasBeenReInserted = mDynamicAABBTree.updateObject(broadPhaseID, aabb, displacement, forceReinsert);
// If the collision shape has moved out of its fat AABB (and therefore has been reinserted
// into the tree).
if (hasBeenReInserted) {
// Add the collision shape into the array of shapes that have moved (or have been created)
// during the last simulation step
addMovedCollisionShape(broadPhaseID);
}
}
void BroadPhaseAlgorithm::reportAllShapesOverlappingWithAABB(const AABB& aabb,
LinkedList<int>& overlappingNodes) const {
AABBOverlapCallback callback(overlappingNodes);
// Ask the dynamic AABB tree to report all collision shapes that overlap with this AABB
mDynamicAABBTree.reportAllShapesOverlappingWithAABB(aabb, callback);
}
// Compute all the overlapping pairs of collision shapes
void BroadPhaseAlgorithm::computeOverlappingPairs(MemoryManager& memoryManager) {
// TODO : Try to see if we can allocate potential pairs in single frame allocator
// Reset the potential overlapping pairs
mNbPotentialPairs = 0;
LinkedList<int> overlappingNodes(memoryManager.getPoolAllocator());
// For all collision shapes that have moved (or have been created) during the
// last simulation step
for (uint i=0; i<mNbMovedShapes; i++) {
int shapeID = mMovedShapes[i];
if (shapeID == -1) continue;
AABBOverlapCallback callback(overlappingNodes);
// Get the AABB of the shape
const AABB& shapeAABB = mDynamicAABBTree.getFatAABB(shapeID);
// Ask the dynamic AABB tree to report all collision shapes that overlap with
// this AABB. The method BroadPhase::notifiyOverlappingPair() will be called
// by the dynamic AABB tree for each potential overlapping pair.
mDynamicAABBTree.reportAllShapesOverlappingWithAABB(shapeAABB, callback);
// Add the potential overlapping pairs
addOverlappingNodes(shapeID, overlappingNodes);
// Remove all the elements of the linked list of overlapping nodes
overlappingNodes.reset();
}
// Reset the array of collision shapes that have move (or have been created) during the
// last simulation step
mNbMovedShapes = 0;
// Sort the array of potential overlapping pairs in order to remove duplicate pairs
std::sort(mPotentialPairs, mPotentialPairs + mNbPotentialPairs, BroadPhasePair::smallerThan);
// Check all the potential overlapping pairs avoiding duplicates to report unique
// overlapping pairs
uint i=0;
while (i < mNbPotentialPairs) {
// Get a potential overlapping pair
BroadPhasePair* pair = mPotentialPairs + i;
i++;
assert(pair->collisionShape1ID != pair->collisionShape2ID);
// Get the two collision shapes of the pair
ProxyShape* shape1 = static_cast<ProxyShape*>(mDynamicAABBTree.getNodeDataPointer(pair->collisionShape1ID));
ProxyShape* shape2 = static_cast<ProxyShape*>(mDynamicAABBTree.getNodeDataPointer(pair->collisionShape2ID));
// If the two proxy collision shapes are from the same body, skip it
if (shape1->getBody()->getID() != shape2->getBody()->getID()) {
// Notify the collision detection about the overlapping pair
mCollisionDetection.broadPhaseNotifyOverlappingPair(shape1, shape2);
}
// Skip the duplicate overlapping pairs
while (i < mNbPotentialPairs) {
// Get the next pair
BroadPhasePair* nextPair = mPotentialPairs + i;
// If the next pair is different from the previous one, we stop skipping pairs
if (nextPair->collisionShape1ID != pair->collisionShape1ID ||
nextPair->collisionShape2ID != pair->collisionShape2ID) {
break;
}
i++;
}
}
// If the number of potential overlapping pairs is less than the quarter of allocated
// number of overlapping pairs
if (mNbPotentialPairs < mNbAllocatedPotentialPairs / 4 && mNbPotentialPairs > 8) {
PoolAllocator& poolAllocator = mCollisionDetection.getMemoryManager().getPoolAllocator();
// Reduce the number of allocated potential overlapping pairs
BroadPhasePair* oldPairs = mPotentialPairs;
uint oldNbAllocatedPotentialPairs = mNbAllocatedPotentialPairs;
mNbAllocatedPotentialPairs /= 2;
mPotentialPairs = static_cast<BroadPhasePair*>(poolAllocator.allocate(mNbAllocatedPotentialPairs * sizeof(BroadPhasePair)));
assert(mPotentialPairs);
memcpy(mPotentialPairs, oldPairs, mNbPotentialPairs * sizeof(BroadPhasePair));
poolAllocator.release(oldPairs, oldNbAllocatedPotentialPairs * sizeof(BroadPhasePair));
}
}
// Notify the broad-phase about a potential overlapping pair in the dynamic AABB tree
void BroadPhaseAlgorithm::addOverlappingNodes(int referenceNodeId, const LinkedList<int>& overlappingNodes) {
// For each overlapping node in the linked list
LinkedList<int>::ListElement* elem = overlappingNodes.getListHead();
while (elem != nullptr) {
// If both the nodes are the same, we do not create store the overlapping pair
if (referenceNodeId != elem->data) {
// If we need to allocate more memory for the array of potential overlapping pairs
if (mNbPotentialPairs == mNbAllocatedPotentialPairs) {
PoolAllocator& poolAllocator = mCollisionDetection.getMemoryManager().getPoolAllocator();
// Allocate more memory for the array of potential pairs
BroadPhasePair* oldPairs = mPotentialPairs;
uint oldNbAllocatedPotentialPairs = mNbAllocatedPotentialPairs;
mNbAllocatedPotentialPairs *= 2;
mPotentialPairs = static_cast<BroadPhasePair*>(poolAllocator.allocate(mNbAllocatedPotentialPairs * sizeof(BroadPhasePair)));
assert(mPotentialPairs);
memcpy(mPotentialPairs, oldPairs, mNbPotentialPairs * sizeof(BroadPhasePair));
poolAllocator.release(oldPairs, oldNbAllocatedPotentialPairs * sizeof(BroadPhasePair));
}
// Add the new potential pair into the array of potential overlapping pairs
mPotentialPairs[mNbPotentialPairs].collisionShape1ID = std::min(referenceNodeId, elem->data);
mPotentialPairs[mNbPotentialPairs].collisionShape2ID = std::max(referenceNodeId, elem->data);
mNbPotentialPairs++;
}
elem = elem->next;
}
}
// Called when a overlapping node has been found during the call to
// DynamicAABBTree:reportAllShapesOverlappingWithAABB()
void AABBOverlapCallback::notifyOverlappingNode(int nodeId) {
mOverlappingNodes.insert(nodeId);
}
// Called for a broad-phase shape that has to be tested for raycast
decimal BroadPhaseRaycastCallback::raycastBroadPhaseShape(int32 nodeId, const Ray& ray) {
decimal hitFraction = decimal(-1.0);
// Get the proxy shape from the node
ProxyShape* proxyShape = static_cast<ProxyShape*>(mDynamicAABBTree.getNodeDataPointer(nodeId));
// Check if the raycast filtering mask allows raycast against this shape
if ((mRaycastWithCategoryMaskBits & proxyShape->getCollisionCategoryBits()) != 0) {
// Ask the collision detection to perform a ray cast test against
// the proxy shape of this node because the ray is overlapping
// with the shape in the broad-phase
hitFraction = mRaycastTest.raycastAgainstShape(proxyShape, ray);
}
return hitFraction;
}