tge/engine/collision/convex.cc
2025-02-17 23:17:30 -06:00

642 lines
18 KiB
C++
Executable File

//-----------------------------------------------------------------------------
// Torque Game Engine
// Copyright (C) GarageGames.com, Inc.
//-----------------------------------------------------------------------------
#include "dgl/dgl.h"
#include "core/dataChunker.h"
#include "collision/collision.h"
#include "sceneGraph/sceneGraph.h"
#include "sim/sceneObject.h"
#include "terrain/terrData.h"
#include "collision/convex.h"
#include "collision/gjk.h"
//----------------------------------------------------------------------------
//----------------------------------------------------------------------------
static DataChunker sChunker;
CollisionStateList CollisionStateList::sFreeList;
CollisionWorkingList CollisionWorkingList::sFreeList;
F32 sqrDistanceEdges(const Point3F& start0,
const Point3F& end0,
const Point3F& start1,
const Point3F& end1,
Point3F* is,
Point3F* it);
//----------------------------------------------------------------------------
// Collision State
//----------------------------------------------------------------------------
CollisionState::CollisionState()
{
mLista = mListb = 0;
}
CollisionState::~CollisionState()
{
if (mLista)
mLista->free();
if (mListb)
mListb->free();
}
void CollisionState::swap()
{
}
void CollisionState::set(Convex* a,Convex* b,const MatrixF& a2w, const MatrixF& b2w)
{
}
F32 CollisionState::distance(const MatrixF& a2w, const MatrixF& b2w, const F32 dontCareDist,
const MatrixF* w2a, const MatrixF* _w2b)
{
return 0;
}
void CollisionState::render()
{
}
//----------------------------------------------------------------------------
// Feature Collision
//----------------------------------------------------------------------------
bool ConvexFeature::collide(ConvexFeature& cf,CollisionList* cList, F32 tol)
{
// Our vertices vs. other faces
const Point3F* vert = mVertexList.begin();
const Point3F* vend = mVertexList.end();
while (vert != vend) {
cf.testVertex(*vert,cList,false, tol);
vert++;
}
// Other vertices vs. our faces
vert = cf.mVertexList.begin();
vend = cf.mVertexList.end();
while (vert != vend) {
U32 storeCount = cList->count;
testVertex(*vert,cList,true, tol);
// Fix up last reference. material and object are copied from this rather
// than the object we're colliding against.
if (storeCount != cList->count) {
cList->collision[cList->count - 1].material = cf.material;
cList->collision[cList->count - 1].object = cf.object;
}
vert++;
}
// Edge vs. Edge
const Edge* edge = mEdgeList.begin();
const Edge* eend = mEdgeList.end();
while (edge != eend) {
cf.testEdge(this,mVertexList[edge->vertex[0]],
mVertexList[edge->vertex[1]],cList, tol);
edge++;
}
return true;
}
inline bool isInside(const Point3F& p, const Point3F& a, const Point3F& b, const VectorF& n)
{
VectorF v;
mCross(n,b - a,&v);
return mDot(v,p - a) < 0.0f;
}
void ConvexFeature::testVertex(const Point3F& v,CollisionList* cList,bool flip, F32 tol)
{
// Test vertex against all faces
const Face* face = mFaceList.begin();
const Face* end = mFaceList.end();
for (; face != end; face++) {
if (cList->count >= CollisionList::MaxCollisions)
return;
const Point3F& p0 = mVertexList[face->vertex[0]];
const Point3F& p1 = mVertexList[face->vertex[1]];
const Point3F& p2 = mVertexList[face->vertex[2]];
// Point near the plane?
F32 distance = mDot(face->normal,v - p0);
if (distance > tol || distance < -tol)
continue;
// Make sure it's within the bounding edges
if (isInside(v,p0,p1,face->normal) && isInside(v,p1,p2,face->normal) &&
isInside(v,p2,p0,face->normal)) {
// Add collision to this face
Collision& info = cList->collision[cList->count++];
info.point = v;
info.normal = face->normal;
if (flip)
info.normal.neg();
info.material = material;
info.object = object;
info.distance = distance;
}
}
}
void ConvexFeature::testEdge(ConvexFeature* cf,const Point3F& s1, const Point3F& e1, CollisionList* cList, F32 tol)
{
F32 tolSquared = tol*tol;
// Test edges against edges
const Edge* edge = mEdgeList.begin();
const Edge* end = mEdgeList.end();
for (; edge != end; edge++) {
if (cList->count >= CollisionList::MaxCollisions)
return;
const Point3F& s2 = mVertexList[edge->vertex[0]];
const Point3F& e2 = mVertexList[edge->vertex[1]];
// Get the distance and closest points
Point3F i1,i2;
F32 distance = sqrDistanceEdges(s1, e1, s2, e2, &i1, &i2);
if (distance > tolSquared)
continue;
distance = mSqrt(distance);
// Need to figure out how to orient the collision normal.
// The current test involves checking to see whether the collision
// points are contained within the convex volumes, which is slow.
if (inVolume(i1) || cf->inVolume(i2))
distance = -distance;
// Contact normal
VectorF normal = i1 - i2;
normal *= 1 / distance;
// Return a collision
Collision& info = cList->collision[cList->count++];
info.point = i1;
info.normal = normal;
info.distance = distance;
info.material = material;
info.object = object;
}
}
bool ConvexFeature::inVolume(const Point3F& v)
{
// Test the point to see if it's inside the volume
const Face* face = mFaceList.begin();
const Face* end = mFaceList.end();
for (; face != end; face++) {
const Point3F& p0 = mVertexList[face->vertex[0]];
if (mDot(face->normal,v - p0) > 0)
return false;
}
return true;
}
//----------------------------------------------------------------------------
// Collision State management
//----------------------------------------------------------------------------
//----------------------------------------------------------------------------
CollisionStateList::CollisionStateList()
{
mPrev = mNext = this;
mState = NULL;
}
void CollisionStateList::linkAfter(CollisionStateList* ptr)
{
mPrev = ptr;
mNext = ptr->mNext;
ptr->mNext = this;
mNext->mPrev = this;
}
void CollisionStateList::unlink()
{
mPrev->mNext = mNext;
mNext->mPrev = mPrev;
mPrev = mNext = this;
}
CollisionStateList* CollisionStateList::alloc()
{
if (!sFreeList.isEmpty()) {
CollisionStateList* nxt = sFreeList.mNext;
nxt->unlink();
nxt->mState = NULL;
return nxt;
}
return constructInPlace((CollisionStateList*)sChunker.alloc(sizeof(CollisionStateList)));
}
void CollisionStateList::free()
{
unlink();
linkAfter(&sFreeList);
}
//----------------------------------------------------------------------------
CollisionWorkingList::CollisionWorkingList()
{
wLink.mPrev = wLink.mNext = this;
rLink.mPrev = rLink.mNext = this;
}
void CollisionWorkingList::wLinkAfter(CollisionWorkingList* ptr)
{
wLink.mPrev = ptr;
wLink.mNext = ptr->wLink.mNext;
ptr->wLink.mNext = this;
wLink.mNext->wLink.mPrev = this;
}
void CollisionWorkingList::rLinkAfter(CollisionWorkingList* ptr)
{
rLink.mPrev = ptr;
rLink.mNext = ptr->rLink.mNext;
ptr->rLink.mNext = this;
rLink.mNext->rLink.mPrev = this;
}
void CollisionWorkingList::unlink()
{
wLink.mPrev->wLink.mNext = wLink.mNext;
wLink.mNext->wLink.mPrev = wLink.mPrev;
wLink.mPrev = wLink.mNext = this;
rLink.mPrev->rLink.mNext = rLink.mNext;
rLink.mNext->rLink.mPrev = rLink.mPrev;
rLink.mPrev = rLink.mNext = this;
}
CollisionWorkingList* CollisionWorkingList::alloc()
{
if (sFreeList.wLink.mNext != &sFreeList) {
CollisionWorkingList* nxt = sFreeList.wLink.mNext;
nxt->unlink();
return nxt;
}
return constructInPlace((CollisionWorkingList*)sChunker.alloc(sizeof(CollisionWorkingList)));
}
void CollisionWorkingList::free()
{
unlink();
wLinkAfter(&sFreeList);
}
//----------------------------------------------------------------------------
// Convex Base Class
//----------------------------------------------------------------------------
U32 Convex::sTag = (U32)-1;
//----------------------------------------------------------------------------
Convex::Convex()
{
mNext = mPrev = this;
mTag = 0;
}
Convex::~Convex()
{
// Unlink from Convex Database
unlink();
// Delete collision states
while (mList.mNext != &mList)
delete mList.mNext->mState;
// Free up working list
while (mWorking.wLink.mNext != &mWorking)
mWorking.wLink.mNext->free();
// Free up references
while (mReference.rLink.mNext != &mReference)
mReference.rLink.mNext->free();
}
//----------------------------------------------------------------------------
void Convex::collectGarbage()
{
// Delete unreferenced Convex Objects
for (Convex* itr = mNext; itr != this; itr = itr->mNext) {
if (itr->mReference.rLink.mNext == &itr->mReference) {
Convex* ptr = itr;
itr = itr->mPrev;
delete ptr;
}
}
}
void Convex::nukeList()
{
// Delete all Convex Objects
for (Convex* itr = mNext; itr != this; itr = itr->mNext) {
Convex* ptr = itr;
itr = itr->mPrev;
delete ptr;
}
}
void Convex::registerObject(Convex *convex)
{
convex->linkAfter(this);
}
//----------------------------------------------------------------------------
void Convex::linkAfter(Convex* ptr)
{
mPrev = ptr;
mNext = ptr->mNext;
ptr->mNext = this;
mNext->mPrev = this;
}
void Convex::unlink()
{
mPrev->mNext = mNext;
mNext->mPrev = mPrev;
mPrev = mNext = this;
}
//----------------------------------------------------------------------------
Point3F Convex::support(const VectorF&) const
{
return Point3F(0,0,0);
}
void Convex::getFeatures(const MatrixF&,const VectorF&,ConvexFeature* f)
{
f->object = NULL;
}
const MatrixF& Convex::getTransform() const
{
return mObject->getTransform();
}
const Point3F& Convex::getScale() const
{
return mObject->getScale();
}
Box3F Convex::getBoundingBox() const
{
return mObject->getWorldBox();
}
Box3F Convex::getBoundingBox(const MatrixF& mat, const Point3F& scale) const
{
Box3F wBox = mObject->getObjBox();
wBox.min.convolve(scale);
wBox.max.convolve(scale);
mat.mul(wBox);
return wBox;
}
void Convex::render()
{
for (CollisionStateList* itr = mList.mNext; itr != &mList; itr = itr->mNext)
if (itr->mState->mLista == itr)
itr->mState->render();
}
//----------------------------------------------------------------------------
void Convex::addToWorkingList(Convex* ptr)
{
CollisionWorkingList* cl = CollisionWorkingList::alloc();
cl->wLinkAfter(&mWorking);
cl->rLinkAfter(&ptr->mReference);
cl->mConvex = ptr;
};
//----------------------------------------------------------------------------
void Convex::updateWorkingList(const Box3F& box, const U32 colMask)
{
sTag++;
// Clear objects off the working list that are no longer intersecting
for (CollisionWorkingList* itr = mWorking.wLink.mNext; itr != &mWorking; itr = itr->wLink.mNext) {
itr->mConvex->mTag = sTag;
if ((!box.isOverlapped(itr->mConvex->getBoundingBox())) || (!itr->mConvex->getObject()->isCollisionEnabled())) {
CollisionWorkingList* cl = itr;
itr = itr->wLink.mPrev;
cl->free();
}
}
// Special processing for the terrain and interiors...
AssertFatal(mObject->getContainer(), "Must be in a container!");
SimpleQueryList sql;
mObject->getContainer()->findObjects(box, colMask,SimpleQueryList::insertionCallback, &sql);
for (U32 i = 0; i < sql.mList.size(); i++)
sql.mList[i]->buildConvex(box, this);
}
// ---------------------------------------------------------------------------
void Convex::updateStateList(const MatrixF& mat, const Point3F& scale, const Point3F* displacement)
{
Box3F box1 = getBoundingBox(mat, scale);
box1.min -= Point3F(1, 1, 1);
box1.max += Point3F(1, 1, 1);
if (displacement) {
Point3F oldMin = box1.min;
Point3F oldMax = box1.max;
box1.min.setMin(oldMin + *displacement);
box1.min.setMin(oldMax + *displacement);
box1.max.setMax(oldMin + *displacement);
box1.max.setMax(oldMax + *displacement);
}
sTag++;
// Destroy states which are no longer intersecting
for (CollisionStateList* itr = mList.mNext; itr != &mList; itr = itr->mNext) {
Convex* cv = (itr->mState->a == this)? itr->mState->b: itr->mState->a;
cv->mTag = sTag;
if (!box1.isOverlapped(cv->getBoundingBox())) {
CollisionState* cs = itr->mState;
itr = itr->mPrev;
delete cs;
}
}
// Add collision states for new overlapping objects
for (CollisionWorkingList* itr0 = mWorking.wLink.mNext; itr0 != &mWorking; itr0 = itr0->wLink.mNext) {
register Convex* cv = itr0->mConvex;
if (cv->mTag != sTag && box1.isOverlapped(cv->getBoundingBox())) {
CollisionState* state = new GjkCollisionState;
state->set(this,cv,mat,cv->getTransform());
state->mLista->linkAfter(&mList);
state->mListb->linkAfter(&cv->mList);
}
}
}
//----------------------------------------------------------------------------
CollisionState* Convex::findClosestState(const MatrixF& mat, const Point3F& scale, const F32 dontCareDist)
{
updateStateList(mat, scale);
F32 dist = +1E30;
CollisionState *st = 0;
// Prepare scaled version of transform
MatrixF axform = mat;
axform.scale(scale);
MatrixF axforminv(true);
MatrixF temp(mat);
axforminv.scale(Point3F(1.0f/scale.x,1.0f/scale.y,1.0f/scale.z));
temp.affineInverse();
axforminv.mul(temp);
for (CollisionStateList* itr = mList.mNext; itr != &mList; itr = itr->mNext) {
CollisionState* state = itr->mState;
if (state->mLista != itr)
state->swap();
// Prepare scaled version of transform
MatrixF bxform = state->b->getTransform();
temp = bxform;
Point3F bscale = state->b->getScale();
bxform.scale(bscale);
MatrixF bxforminv(true);
bxforminv.scale(Point3F(1.0f/bscale.x,1.0f/bscale.y,1.0f/bscale.z));
temp.affineInverse();
bxforminv.mul(temp);
//
F32 dd = state->distance(axform, bxform, dontCareDist, &axforminv, &bxforminv);
if (dd < dist) {
dist = dd;
st = state;
}
}
if (dist < dontCareDist)
return st;
else
return NULL;
}
//----------------------------------------------------------------------------
bool Convex::getCollisionInfo(const MatrixF& mat, const Point3F& scale, CollisionList* cList,F32 tol)
{
for (CollisionStateList* itr = mList.mNext; itr != &mList; itr = itr->mNext) {
CollisionState* state = itr->mState;
if (state->mLista != itr)
state->swap();
if (state->dist <= tol) {
ConvexFeature fa,fb;
VectorF v;
// The idea is that we need to scale the matrix, so we need to
// make a copy of it, before we can pass it in to getFeatures.
// This is used to scale us for comparison against the other
// convex, which is correctly scaled.
MatrixF omat = mat;
omat.scale(scale);
MatrixF imat = omat;
imat.inverse();
imat.mulV(-state->v,&v);
getFeatures(omat,v,&fa);
imat = state->b->getTransform();
imat.scale(state->b->getScale());
MatrixF bxform = imat;
imat.inverse();
imat.mulV(state->v,&v);
state->b->getFeatures(bxform,v,&fb);
fa.collide(fb,cList,tol);
}
}
return (cList->count != 0);
}
void Convex::getPolyList(AbstractPolyList*)
{
}
//-----------------------------------------------------------------------------
// This function based on code orignally written for the book:
// 3D Game Engine Design, by David H. Eberly
//
F32 sqrDistanceEdges(const Point3F& start0, const Point3F& end0,
const Point3F& start1, const Point3F& end1,
Point3F* is, Point3F* it)
{
Point3F direction0 = end0 - start0;
F32 fA00 = direction0.lenSquared();
Point3F direction1 = end1 - start1;
F32 fA11 = direction1.lenSquared();
F32 fA01 = -mDot(direction0, direction1);
Point3F kDiff = start0 - start1;
F32 fC = kDiff.lenSquared();
F32 fB0 = mDot(kDiff, direction0);
F32 fDet = mAbs((S32)(fA00*fA11 - fA01*fA01));
// Since the endpoints are tested as vertices, we're not interested
// in parallel lines, and intersections that don't involve end-points.
if (fDet >= 0.00001) {
// Calculate time of intersection for each line
F32 fB1 = -mDot(kDiff, direction1);
F32 fS = fA01*fB1-fA11*fB0;
F32 fT = fA01*fB0-fA00*fB1;
// Only interested in collisions that don't involve the end points
if (fS >= 0.0 && fS <= fDet && fT >= 0.0 && fT <= fDet) {
F32 fInvDet = 1.0 / fDet;
fS *= fInvDet;
fT *= fInvDet;
F32 fSqrDist = (fS*(fA00*fS + fA01*fT + 2.0*fB0) +
fT*(fA01*fS + fA11*fT + 2.0*fB1) + fC);
// Intersection points.
*is = start0 + direction0 * fS;
*it = start1 + direction1 * fT;
return mFabs(fSqrDist);
}
}
// Return a large number in the cases where endpoints are involved.
return 1e10f;
}