reactphysics3d/src/collision/CollisionDetection.cpp

263 lines
12 KiB
C++

/********************************************************************************
* ReactPhysics3D physics library, http://code.google.com/p/reactphysics3d/ *
* Copyright (c) 2010-2012 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 "CollisionDetection.h"
#include "../engine/CollisionWorld.h"
#include "../body/Body.h"
#include "../collision/shapes/BoxShape.h"
#include "../body/RigidBody.h"
#include "../configuration.h"
#include <cassert>
#include <complex>
#include <set>
#include <utility>
#include <utility>
// We want to use the ReactPhysics3D namespace
using namespace reactphysics3d;
using namespace std;
// Constructor
CollisionDetection::CollisionDetection(CollisionWorld* world, MemoryAllocator& memoryAllocator)
: mWorld(world), mBroadPhaseAlgorithm(*this),
mNarrowPhaseGJKAlgorithm(memoryAllocator),
mNarrowPhaseSphereVsSphereAlgorithm(memoryAllocator),
mIsCollisionShapesAdded(false) {
}
// Destructor
CollisionDetection::~CollisionDetection() {
}
// Compute the collision detection
void CollisionDetection::computeCollisionDetection() {
PROFILE("CollisionDetection::computeCollisionDetection()");
// Compute the broad-phase collision detection
computeBroadPhase();
// Compute the narrow-phase collision detection
computeNarrowPhase();
}
// Compute the broad-phase collision detection
void CollisionDetection::computeBroadPhase() {
PROFILE("CollisionDetection::computeBroadPhase()");
// If new collision shapes have been added to bodies
if (mIsCollisionShapesAdded) {
// Ask the broad-phase to recompute the overlapping pairs of collision
// shapes. This call can only add new overlapping pairs in the collision
// detection.
mBroadPhaseAlgorithm.computeOverlappingPairs();
}
}
// Compute the narrow-phase collision detection
void CollisionDetection::computeNarrowPhase() {
PROFILE("CollisionDetection::computeNarrowPhase()");
// For each possible collision pair of bodies
map<overlappingpairid, OverlappingPair*>::iterator it;
for (it = mOverlappingPairs.begin(); it != mOverlappingPairs.end(); it++) {
ContactPointInfo* contactInfo = NULL;
OverlappingPair* pair = it->second;
ProxyShape* shape1 = pair->getShape1();
ProxyShape* shape2 = pair->getShape2();
CollisionBody* const body1 = shape1->getBody();
CollisionBody* const body2 = shape2->getBody();
// Update the contact cache of the overlapping pair
pair->update();
// Check if the two bodies are allowed to collide, otherwise, we do not test for collision
if (body1->getType() != DYNAMIC && body2->getType() != DYNAMIC) continue;
bodyindexpair bodiesIndex = OverlappingPair::computeBodiesIndexPair(body1, body2);
if (mNoCollisionPairs.count(bodiesIndex) > 0) continue;
// Check if the two bodies are sleeping, if so, we do no test collision between them
if (body1->isSleeping() && body2->isSleeping()) continue;
// Select the narrow phase algorithm to use according to the two collision shapes
NarrowPhaseAlgorithm& narrowPhaseAlgorithm = SelectNarrowPhaseAlgorithm(
shape1->getCollisionShape(),
shape2->getCollisionShape());
// Notify the narrow-phase algorithm about the overlapping pair we are going to test
narrowPhaseAlgorithm.setCurrentOverlappingPair(pair);
// Use the narrow-phase collision detection algorithm to check
// if there really is a collision
const Transform transform1 = body1->getTransform() * shape1->getLocalToBodyTransform();
const Transform transform2 = body2->getTransform() * shape2->getLocalToBodyTransform();
if (narrowPhaseAlgorithm.testCollision(shape1, shape2, contactInfo)) {
assert(contactInfo != NULL);
// Set the bodies of the contact
contactInfo->body1 = dynamic_cast<RigidBody*>(body1);
contactInfo->body2 = dynamic_cast<RigidBody*>(body2);
assert(contactInfo->body1 != NULL);
assert(contactInfo->body2 != NULL);
// Create a new contact
createContact(pair, contactInfo);
// Delete and remove the contact info from the memory allocator
contactInfo->ContactPointInfo::~ContactPointInfo();
mWorld->mMemoryAllocator.release(contactInfo, sizeof(ContactPointInfo));
}
}
}
// Allow the broadphase to notify the collision detection about an overlapping pair.
/// This method is called by a broad-phase collision detection algorithm
void CollisionDetection::broadPhaseNotifyOverlappingPair(ProxyShape* shape1, ProxyShape* shape2) {
// Compute the overlapping pair ID
overlappingpairid pairID = OverlappingPair::computeID(shape1, shape2);
// Check if the overlapping pair already exists
if (mOverlappingPairs.find(pairID) != mOverlappingPairs.end()) return;
// Create the overlapping pair and add it into the set of overlapping pairs
OverlappingPair* newPair = new (mWorld->mMemoryAllocator.allocate(sizeof(OverlappingPair)))
OverlappingPair(shape1, shape2, mWorld->mMemoryAllocator);
assert(newPair != NULL);
std::pair<map<overlappingpairid, OverlappingPair*>::iterator, bool> check =
mOverlappingPairs.insert(make_pair(pairID, newPair));
assert(check.second);
/* TODO : DELETE THIS
// Get the pair of body index
bodyindexpair indexPair = addedPair->getBodiesIndexPair();
// If the overlapping pair already exists, we don't do anything
if (mOverlappingPairs.count(indexPair) > 0) return;
// Create the corresponding broad-phase pair object
BroadPhasePair* broadPhasePair = new (mWorld->mMemoryAllocator.allocate(sizeof(BroadPhasePair)))
BroadPhasePair(addedPair->body1, addedPair->body2);
assert(broadPhasePair != NULL);
// Add the pair into the set of overlapping pairs (if not there yet)
pair<map<bodyindexpair, BroadPhasePair*>::iterator, bool> check = mOverlappingPairs.insert(
make_pair(indexPair,
broadPhasePair));
assert(check.second);
// Notify the world about the new broad-phase overlapping pair
mWorld->notifyAddedOverlappingPair(broadPhasePair);
*/
}
// Remove a body from the collision detection
void CollisionDetection::removeProxyCollisionShape(ProxyShape* proxyShape) {
// Remove all the overlapping pairs involving this proxy shape
std::map<overlappingpairid, OverlappingPair*>::iterator it;
for (it = mOverlappingPairs.begin(); it != mOverlappingPairs.end(); ) {
if (it->second->getShape1()->mBroadPhaseID == proxyShape->mBroadPhaseID||
it->second->getShape2()->mBroadPhaseID == proxyShape->mBroadPhaseID) {
std::map<overlappingpairid, OverlappingPair*>::iterator itToRemove = it;
++it;
// Destroy the overlapping pair
itToRemove->second->OverlappingPair::~OverlappingPair();
mWorld->mMemoryAllocator.release(itToRemove->second, sizeof(OverlappingPair));
mOverlappingPairs.erase(itToRemove);
}
else {
++it;
}
}
// Remove the body from the broad-phase
mBroadPhaseAlgorithm.removeProxyCollisionShape(proxyShape);
}
// Create a new contact
void CollisionDetection::createContact(OverlappingPair* overlappingPair,
const ContactPointInfo* contactInfo) {
// Create a new contact
ContactPoint* contact = new (mWorld->mMemoryAllocator.allocate(sizeof(ContactPoint)))
ContactPoint(*contactInfo);
assert(contact != NULL);
// If it is the first contact since the pair are overlapping
if (overlappingPair->getNbContactPoints() == 0) {
// Trigger a callback event
if (mWorld->mEventListener != NULL) mWorld->mEventListener->beginContact(*contactInfo);
}
// Add the contact to the contact cache of the corresponding overlapping pair
overlappingPair->addContact(contact);
// Add the contact manifold to the list of contact manifolds
mContactManifolds.push_back(overlappingPair->getContactManifold());
// Add the contact manifold into the list of contact manifolds
// of the two bodies involved in the contact
addContactManifoldToBody(overlappingPair->getContactManifold(),
overlappingPair->getShape1()->getBody(),
overlappingPair->getShape2()->getBody());
// Trigger a callback event for the new contact
if (mWorld->mEventListener != NULL) mWorld->mEventListener->newContact(*contactInfo);
}
// Add a contact manifold to the linked list of contact manifolds of the two bodies involved
// in the corresponding contact
void CollisionDetection::addContactManifoldToBody(ContactManifold* contactManifold,
CollisionBody* body1, CollisionBody* body2) {
assert(contactManifold != NULL);
// Add the contact manifold at the beginning of the linked
// list of contact manifolds of the first body
void* allocatedMemory1 = mWorld->mMemoryAllocator.allocate(sizeof(ContactManifoldListElement));
ContactManifoldListElement* listElement1 = new (allocatedMemory1)
ContactManifoldListElement(contactManifold,
body1->mContactManifoldsList);
body1->mContactManifoldsList = listElement1;
// Add the joint at the beginning of the linked list of joints of the second body
void* allocatedMemory2 = mWorld->mMemoryAllocator.allocate(sizeof(ContactManifoldListElement));
ContactManifoldListElement* listElement2 = new (allocatedMemory2)
ContactManifoldListElement(contactManifold,
body2->mContactManifoldsList);
body2->mContactManifoldsList = listElement2;
}