diff options
Diffstat (limited to 'third-party/Opcode/OPC_SweepAndPrune.cpp')
| -rw-r--r-- | third-party/Opcode/OPC_SweepAndPrune.cpp | 664 |
1 files changed, 664 insertions, 0 deletions
diff --git a/third-party/Opcode/OPC_SweepAndPrune.cpp b/third-party/Opcode/OPC_SweepAndPrune.cpp new file mode 100644 index 0000000..e56e7ab --- /dev/null +++ b/third-party/Opcode/OPC_SweepAndPrune.cpp @@ -0,0 +1,664 @@ +/////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////// +/* + * OPCODE - Optimized Collision Detection + * Copyright (C) 2001 Pierre Terdiman + * Homepage: http://www.codercorner.com/Opcode.htm + */ +/////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////// + +/////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////// +/** + * Contains an implementation of the sweep-and-prune algorithm (moved from Z-Collide) + * \file OPC_SweepAndPrune.cpp + * \author Pierre Terdiman + * \date January, 29, 2000 + */ +/////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////// + +/////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////// +// Precompiled Header +#include "StdAfx.h" + +using namespace Opcode; + +inline_ void Sort(udword& id0, udword& id1) +{ + if(id0>id1) Swap(id0, id1); +} + + class Opcode::SAP_Element + { + public: + inline_ SAP_Element() {} + inline_ SAP_Element(udword id, SAP_Element* next) : mID(id), mNext(next) {} + inline_ ~SAP_Element() {} + + udword mID; + SAP_Element* mNext; + }; + + class Opcode::SAP_Box + { + public: + SAP_EndPoint* Min[3]; + SAP_EndPoint* Max[3]; + }; + + class Opcode::SAP_EndPoint + { + public: + float Value; // Min or Max value + SAP_EndPoint* Previous; // Previous EndPoint whose Value is smaller than ours (or null) + SAP_EndPoint* Next; // Next EndPoint whose Value is greater than ours (or null) + udword Data; // Parent box ID *2 | MinMax flag + + inline_ void SetData(udword box_id, BOOL is_max) { Data = (box_id<<1)|is_max; } + inline_ BOOL IsMax() const { return Data & 1; } + inline_ udword GetBoxID() const { return Data>>1; } + + inline_ void InsertAfter(SAP_EndPoint* element) + { + if(this!=element && this!=element->Next) + { + // Remove + if(Previous) Previous->Next = Next; + if(Next) Next->Previous = Previous; + + // Insert + Next = element->Next; + if(Next) Next->Previous = this; + + element->Next = this; + Previous = element; + } + } + + inline_ void InsertBefore(SAP_EndPoint* element) + { + if(this!=element && this!=element->Previous) + { + // Remove + if(Previous) Previous->Next = Next; + if(Next) Next->Previous = Previous; + + // Insert + Previous = element->Previous; + element->Previous = this; + + Next = element; + if(Previous) Previous->Next = this; + } + } + }; + + + + + + + + + + +/////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////// +/** + * Constructor. + */ +/////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////// +SAP_PairData::SAP_PairData() : + mNbElements (0), + mNbUsedElements (0), + mElementPool (null), + mFirstFree (null), + mNbObjects (0), + mArray (null) +{ +} + +/////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////// +/** + * Destructor. + */ +/////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////// +SAP_PairData::~SAP_PairData() +{ + Release(); +} + +void SAP_PairData::Release() +{ + mNbElements = 0; + mNbUsedElements = 0; + mNbObjects = 0; + DELETEARRAY(mElementPool); + DELETEARRAY(mArray); +} + +/////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////// +/** + * Initializes. + * \param nb_objects [in] + * \return true if success + */ +/////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////// +bool SAP_PairData::Init(udword nb_objects) +{ + // Make sure everything has been released + Release(); + if(!nb_objects) return false; + + mArray = new SAP_Element*[nb_objects]; + CHECKALLOC(mArray); + ZeroMemory(mArray, nb_objects*sizeof(SAP_Element*)); + mNbObjects = nb_objects; + + return true; +} + +/////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////// +/** + * Remaps a pointer when pool gets resized. + * \param element [in/out] remapped element + * \param delta [in] offset in bytes + */ +/////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////// +inline_ void Remap(SAP_Element*& element, udword delta) +{ + if(element) element = (SAP_Element*)(udword(element) + delta); +} + +/////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////// +/** + * Gets a free element in the pool. + * \param id [in] element id + * \param next [in] next element + * \param remap [out] possible remapping offset + * \return the new element + */ +/////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////// +SAP_Element* SAP_PairData::GetFreeElem(udword id, SAP_Element* next, udword* remap) +{ + if(remap) *remap = 0; + + SAP_Element* FreeElem; + if(mFirstFree) + { + // Recycle + FreeElem = mFirstFree; + mFirstFree = mFirstFree->mNext; // First free = next free (or null) + } + else + { + if(mNbUsedElements==mNbElements) + { + // Resize + mNbElements = mNbElements ? (mNbElements<<1) : 2; + + SAP_Element* NewElems = new SAP_Element[mNbElements]; + + if(mNbUsedElements) CopyMemory(NewElems, mElementPool, mNbUsedElements*sizeof(SAP_Element)); + + // Remap everything + { + udword Delta = udword(NewElems) - udword(mElementPool); + + for(udword i=0;i<mNbUsedElements;i++) Remap(NewElems[i].mNext, Delta); + for(udword i=0;i<mNbObjects;i++) Remap(mArray[i], Delta); + + Remap(mFirstFree, Delta); + Remap(next, Delta); + + if(remap) *remap = Delta; + } + + DELETEARRAY(mElementPool); + mElementPool = NewElems; + } + + FreeElem = &mElementPool[mNbUsedElements++]; + } + + FreeElem->mID = id; + FreeElem->mNext = next; + + return FreeElem; +} + +/////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////// +/** + * Frees an element of the pool. + * \param elem [in] element to free/recycle + */ +/////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////// +inline_ void SAP_PairData::FreeElem(SAP_Element* elem) +{ + elem->mNext = mFirstFree; // Next free + mFirstFree = elem; +} + +// Add a pair to the set. +void SAP_PairData::AddPair(udword id1, udword id2) +{ + // Order the ids + Sort(id1, id2); + + ASSERT(id1<mNbObjects); + if(id1>=mNbObjects) return; + + // Select the right list from "mArray". + SAP_Element* Current = mArray[id1]; + + if(!Current) + { + // Empty slot => create new element + mArray[id1] = GetFreeElem(id2, null); + } + else if(Current->mID>id2) + { + // The list is not empty but all elements are greater than id2 => insert id2 in the front. + mArray[id1] = GetFreeElem(id2, mArray[id1]); + } + else + { + // Else find the correct location in the sorted list (ascending order) and insert id2 there. + while(Current->mNext) + { + if(Current->mNext->mID > id2) break; + + Current = Current->mNext; + } + + if(Current->mID==id2) return; // The pair already exists + +// Current->mNext = GetFreeElem(id2, Current->mNext); + udword Delta; + SAP_Element* E = GetFreeElem(id2, Current->mNext, &Delta); + if(Delta) Remap(Current, Delta); + Current->mNext = E; + } +} + +// Delete a pair from the set. +void SAP_PairData::RemovePair(udword id1, udword id2) +{ + // Order the ids. + Sort(id1, id2); + + // Exit if the pair doesn't exist in the set + if(id1>=mNbObjects) return; + + // Otherwise, select the correct list. + SAP_Element* Current = mArray[id1]; + + // If this list is empty, the pair doesn't exist. + if(!Current) return; + + // Otherwise, if id2 is the first element, delete it. + if(Current->mID==id2) + { + mArray[id1] = Current->mNext; + FreeElem(Current); + } + else + { + // If id2 is not the first element, start traversing the sorted list. + while(Current->mNext) + { + // If we have moved too far away without hitting id2, then the pair doesn't exist + if(Current->mNext->mID > id2) return; + + // Otherwise, delete id2. + if(Current->mNext->mID == id2) + { + SAP_Element* Temp = Current->mNext; + Current->mNext = Temp->mNext; + FreeElem(Temp); + return; + } + Current = Current->mNext; + } + } +} + +void SAP_PairData::DumpPairs(Pairs& pairs) const +{ + // ### Ugly and slow + for(udword i=0;i<mNbObjects;i++) + { + SAP_Element* Current = mArray[i]; + while(Current) + { + ASSERT(Current->mID<mNbObjects); + + pairs.AddPair(i, Current->mID); + Current = Current->mNext; + } + } +} + +void SAP_PairData::DumpPairs(PairCallback callback, void* user_data) const +{ + if(!callback) return; + + // ### Ugly and slow + for(udword i=0;i<mNbObjects;i++) + { + SAP_Element* Current = mArray[i]; + while(Current) + { + ASSERT(Current->mID<mNbObjects); + + if(!(callback)(i, Current->mID, user_data)) return; + Current = Current->mNext; + } + } +} + + + + + + + + + + + + + + + + + + + + + + + + + + + + +/////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////// +/** + * Constructor. + */ +/////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////// +SweepAndPrune::SweepAndPrune() +{ +} + +/////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////// +/** + * Destructor. + */ +/////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////// +SweepAndPrune::~SweepAndPrune() +{ +} + +void SweepAndPrune::GetPairs(Pairs& pairs) const +{ + mPairs.DumpPairs(pairs); +} + +void SweepAndPrune::GetPairs(PairCallback callback, void* user_data) const +{ + mPairs.DumpPairs(callback, user_data); +} + +bool SweepAndPrune::Init(udword nb_objects, const AABB** boxes) +{ + // 1) Create sorted lists + mNbObjects = nb_objects; + + mBoxes = new SAP_Box[nb_objects]; +// for(udword i=0;i<nb_objects;i++) mBoxes[i].Box = *boxes[i]; + + float* Data = new float[nb_objects*2]; + + for(udword Axis=0;Axis<3;Axis++) + { + mList[Axis] = new SAP_EndPoint[nb_objects*2]; + + for(udword i=0;i<nb_objects;i++) + { + Data[i*2+0] = boxes[i]->GetMin(Axis); + Data[i*2+1] = boxes[i]->GetMax(Axis); + } + RadixSort RS; + const udword* Sorted = RS.Sort(Data, nb_objects*2).GetRanks(); + + SAP_EndPoint* PreviousEndPoint = null; + + for(udword i=0;i<nb_objects*2;i++) + { + udword SortedIndex = *Sorted++; + float SortedCoord = Data[SortedIndex]; + udword BoxIndex = SortedIndex>>1; + + ASSERT(BoxIndex<nb_objects); + + SAP_EndPoint* CurrentEndPoint = &mList[Axis][SortedIndex]; + CurrentEndPoint->Value = SortedCoord; +// CurrentEndPoint->IsMax = SortedIndex&1; // ### could be implicit ? +// CurrentEndPoint->ID = BoxIndex; // ### could be implicit ? + CurrentEndPoint->SetData(BoxIndex, SortedIndex&1); // ### could be implicit ? + CurrentEndPoint->Previous = PreviousEndPoint; + CurrentEndPoint->Next = null; + if(PreviousEndPoint) PreviousEndPoint->Next = CurrentEndPoint; + + if(CurrentEndPoint->IsMax()) mBoxes[BoxIndex].Max[Axis] = CurrentEndPoint; + else mBoxes[BoxIndex].Min[Axis] = CurrentEndPoint; + + PreviousEndPoint = CurrentEndPoint; + } + } + + DELETEARRAY(Data); + + CheckListsIntegrity(); + + // 2) Quickly find starting pairs + + mPairs.Init(nb_objects); + + { + Pairs P; + CompleteBoxPruning(nb_objects, boxes, P, Axes(AXES_XZY)); + for(udword i=0;i<P.GetNbPairs();i++) + { + const Pair* PP = P.GetPair(i); + + udword id0 = PP->id0; + udword id1 = PP->id1; + + if(id0!=id1 && boxes[id0]->Intersect(*boxes[id1])) + { + mPairs.AddPair(id0, id1); + } + else ASSERT(0); + } + } + + return true; +} + +bool SweepAndPrune::CheckListsIntegrity() +{ + for(udword Axis=0;Axis<3;Axis++) + { + // Find list head + SAP_EndPoint* Current = mList[Axis]; + while(Current->Previous) Current = Current->Previous; + + udword Nb = 0; + + SAP_EndPoint* Previous = null; + while(Current) + { + Nb++; + + if(Previous) + { + ASSERT(Previous->Value <= Current->Value); + if(Previous->Value > Current->Value) return false; + } + + ASSERT(Current->Previous==Previous); + if(Current->Previous!=Previous) return false; + + Previous = Current; + Current = Current->Next; + } + + ASSERT(Nb==mNbObjects*2); + } + return true; +} + +inline_ BOOL Intersect(const AABB& a, const SAP_Box& b) +{ + if(b.Max[0]->Value < a.GetMin(0) || a.GetMax(0) < b.Min[0]->Value + || b.Max[1]->Value < a.GetMin(1) || a.GetMax(1) < b.Min[1]->Value + || b.Max[2]->Value < a.GetMin(2) || a.GetMax(2) < b.Min[2]->Value) return FALSE; + + return TRUE; +} + + + +bool SweepAndPrune::UpdateObject(udword i, const AABB& box) +{ + for(udword Axis=0;Axis<3;Axis++) + { +// udword Base = (udword)&mList[Axis][0]; + + // Update min + { + SAP_EndPoint* const CurrentMin = mBoxes[i].Min[Axis]; + ASSERT(!CurrentMin->IsMax()); + + const float Limit = box.GetMin(Axis); + if(Limit == CurrentMin->Value) + { + } + else if(Limit < CurrentMin->Value) + { + CurrentMin->Value = Limit; + + // Min is moving left: + SAP_EndPoint* NewPos = CurrentMin; + ASSERT(NewPos); + + SAP_EndPoint* tmp; + while((tmp = NewPos->Previous) && tmp->Value > Limit) + { + NewPos = tmp; + + if(NewPos->IsMax()) + { + // Our min passed a max => start overlap + //udword SortedIndex = (udword(CurrentMin) - Base)/sizeof(NS_EndPoint); + const udword id0 = CurrentMin->GetBoxID(); + const udword id1 = NewPos->GetBoxID(); + + if(id0!=id1 && Intersect(box, mBoxes[id1])) mPairs.AddPair(id0, id1); + } + } + + CurrentMin->InsertBefore(NewPos); + } + else// if(Limit > CurrentMin->Value) + { + CurrentMin->Value = Limit; + + // Min is moving right: + SAP_EndPoint* NewPos = CurrentMin; + ASSERT(NewPos); + + SAP_EndPoint* tmp; + while((tmp = NewPos->Next) && tmp->Value < Limit) + { + NewPos = tmp; + + if(NewPos->IsMax()) + { + // Our min passed a max => stop overlap + const udword id0 = CurrentMin->GetBoxID(); + const udword id1 = NewPos->GetBoxID(); + + if(id0!=id1) mPairs.RemovePair(id0, id1); + } + } + + CurrentMin->InsertAfter(NewPos); + } + } + + // Update max + { + SAP_EndPoint* const CurrentMax = mBoxes[i].Max[Axis]; + ASSERT(CurrentMax->IsMax()); + + const float Limit = box.GetMax(Axis); + if(Limit == CurrentMax->Value) + { + } + else if(Limit > CurrentMax->Value) + { + CurrentMax->Value = Limit; + + // Max is moving right: + SAP_EndPoint* NewPos = CurrentMax; + ASSERT(NewPos); + + SAP_EndPoint* tmp; + while((tmp = NewPos->Next) && tmp->Value < Limit) + { + NewPos = tmp; + + if(!NewPos->IsMax()) + { + // Our max passed a min => start overlap + const udword id0 = CurrentMax->GetBoxID(); + const udword id1 = NewPos->GetBoxID(); + + if(id0!=id1 && Intersect(box, mBoxes[id1])) mPairs.AddPair(id0, id1); + } + } + + CurrentMax->InsertAfter(NewPos); + } + else// if(Limit < CurrentMax->Value) + { + CurrentMax->Value = Limit; + + // Max is moving left: + SAP_EndPoint* NewPos = CurrentMax; + ASSERT(NewPos); + + SAP_EndPoint* tmp; + while((tmp = NewPos->Previous) && tmp->Value > Limit) + { + NewPos = tmp; + + if(!NewPos->IsMax()) + { + // Our max passed a min => stop overlap + const udword id0 = CurrentMax->GetBoxID(); + const udword id1 = NewPos->GetBoxID(); + + if(id0!=id1) mPairs.RemovePair(id0, id1); + } + } + + CurrentMax->InsertBefore(NewPos); + } + } + } + + return true; +} |