// This one is complicated and gross. Just don't go there...
// TODO: Comment me!
static int
seg2poly(const cpShape *shape1, const cpShape *shape2, cpContact *arr)
{
cpSegmentShape *seg = (cpSegmentShape *)shape1;
cpPolyShape *poly = (cpPolyShape *)shape2;
cpSplittingPlane *planes = poly->tPlanes;
cpFloat segD = cpvdot(seg->tn, seg->ta);
cpFloat minNorm = cpPolyShapeValueOnAxis(poly, seg->tn, segD) - seg->r;
cpFloat minNeg = cpPolyShapeValueOnAxis(poly, cpvneg(seg->tn), -segD) - seg->r;
if(minNeg > 0.0f || minNorm > 0.0f) return 0;
int mini = 0;
cpFloat poly_min = segValueOnAxis(seg, planes->n, planes->d);
if(poly_min > 0.0f) return 0;
for(int i=0; i<poly->numVerts; i++){
cpFloat dist = segValueOnAxis(seg, planes[i].n, planes[i].d);
if(dist > 0.0f){
return 0;
} else if(dist > poly_min){
poly_min = dist;
mini = i;
}
}
int num = 0;
cpVect poly_n = cpvneg(planes[mini].n);
cpVect va = cpvadd(seg->ta, cpvmult(poly_n, seg->r));
cpVect vb = cpvadd(seg->tb, cpvmult(poly_n, seg->r));
if(cpPolyShapeContainsVert(poly, va))
cpContactInit(nextContactPoint(arr, &num), va, poly_n, poly_min, CP_HASH_PAIR(seg->shape.hashid, 0));
if(cpPolyShapeContainsVert(poly, vb))
cpContactInit(nextContactPoint(arr, &num), vb, poly_n, poly_min, CP_HASH_PAIR(seg->shape.hashid, 1));
// Floating point precision problems here.
// This will have to do for now.
// poly_min -= cp_collision_slop; // TODO is this needed anymore?
if(minNorm >= poly_min || minNeg >= poly_min) {
if(minNorm > minNeg)
findPointsBehindSeg(arr, &num, seg, poly, minNorm, 1.0f);
else
findPointsBehindSeg(arr, &num, seg, poly, minNeg, -1.0f);
}
// If no other collision points are found, try colliding endpoints.
if(num == 0){
cpVect poly_a = poly->tVerts[mini];
cpVect poly_b = poly->tVerts[(mini + 1)%poly->numVerts];
if(circle2circleQuery(seg->ta, poly_a, seg->r, 0.0f, arr)) return 1;
if(circle2circleQuery(seg->tb, poly_a, seg->r, 0.0f, arr)) return 1;
if(circle2circleQuery(seg->ta, poly_b, seg->r, 0.0f, arr)) return 1;
if(circle2circleQuery(seg->tb, poly_b, seg->r, 0.0f, arr)) return 1;
}
return num;
}
static struct Edge
SupportEdgeForSegment(const cpSegmentShape *seg, const cpVect n)
{
cpHashValue hashid = seg->shape.hashid;
if(cpvdot(seg->tn, n) > 0.0) {
struct Edge edge = {{seg->ta, CP_HASH_PAIR(hashid, 0)}, {seg->tb, CP_HASH_PAIR(hashid, 1)}, seg->r, seg->tn};
return edge;
} else {
struct Edge edge = {{seg->tb, CP_HASH_PAIR(hashid, 1)}, {seg->ta, CP_HASH_PAIR(hashid, 0)}, seg->r, cpvneg(seg->tn)};
return edge;
}
}
// This one is complicated and gross. Just don't go there...
// TODO: Comment me!
static int
seg2poly(cpShape *shape1, cpShape *shape2, cpContact **arr)
{
cpSegmentShape *seg = (cpSegmentShape *)shape1;
cpPolyShape *poly = (cpPolyShape *)shape2;
cpPolyShapeAxis *axes = poly->tAxes;
cpFloat segD = cpvdot(seg->tn, seg->ta);
cpFloat minNorm = cpPolyShapeValueOnAxis(poly, seg->tn, segD) - seg->r;
cpFloat minNeg = cpPolyShapeValueOnAxis(poly, cpvneg(seg->tn), -segD) - seg->r;
if(minNeg > 0.0f || minNorm > 0.0f) return 0;
int mini = 0;
cpFloat poly_min = segValueOnAxis(seg, axes->n, axes->d);
if(poly_min > 0.0f) return 0;
for(int i=0; i<poly->numVerts; i++){
cpFloat dist = segValueOnAxis(seg, axes[i].n, axes[i].d);
if(dist > 0.0f){
return 0;
} else if(dist > poly_min){
poly_min = dist;
mini = i;
}
}
int max = 0;
int num = 0;
cpVect poly_n = cpvneg(axes[mini].n);
cpVect va = cpvadd(seg->ta, cpvmult(poly_n, seg->r));
cpVect vb = cpvadd(seg->tb, cpvmult(poly_n, seg->r));
if(cpPolyShapeContainsVert(poly, va))
cpContactInit(addContactPoint(arr, &max, &num), va, poly_n, poly_min, CP_HASH_PAIR(seg, 0));
if(cpPolyShapeContainsVert(poly, vb))
cpContactInit(addContactPoint(arr, &max, &num), vb, poly_n, poly_min, CP_HASH_PAIR(seg, 1));
// Floating point precision problems here.
// This will have to do for now.
poly_min -= cp_collision_slop;
if(minNorm >= poly_min || minNeg >= poly_min) {
if(minNorm > minNeg)
findPointsBehindSeg(arr, &max, &num, seg, poly, minNorm, 1.0f);
else
findPointsBehindSeg(arr, &max, &num, seg, poly, minNeg, -1.0f);
}
return num;
}
void
cpSpaceRemoveCollisionHandler(cpSpace *space, cpCollisionType a, cpCollisionType b)
{
struct{cpCollisionType a, b;} ids = {a, b};
cpCollisionHandler *old_handler = cpHashSetRemove(space->collFuncSet, CP_HASH_PAIR(a, b), &ids);
cpfree(old_handler);
}
void
cpSpaceAddCollisionHandler(
cpSpace *space,
cpCollisionType a, cpCollisionType b,
cpCollisionBeginFunc begin,
cpCollisionPreSolveFunc preSolve,
cpCollisionPostSolveFunc postSolve,
cpCollisionSeparateFunc separate,
void *data
){
cpAssertSpaceUnlocked(space);
// Remove any old function so the new one will get added.
cpSpaceRemoveCollisionHandler(space, a, b);
cpCollisionHandler handler = {
a, b,
begin ? begin : alwaysCollide,
preSolve ? preSolve : alwaysCollide,
postSolve ? postSolve : nothing,
separate ? separate : nothing,
data
};
cpHashSetInsert(space->collFuncSet, CP_HASH_PAIR(a, b), &handler, NULL);
}
// Callback from the spatial hash.
static void
queryFunc(cpShape *a, cpShape *b, cpSpace *space)
{
// Reject any of the simple cases
if(queryReject(a,b)) return;
cpCollisionHandler *handler = lookupCollisionHandler(space, a->collision_type, b->collision_type);
cpBool sensor = a->sensor || b->sensor;
if(sensor && handler == &cpSpaceDefaultHandler) return;
// Shape 'a' should have the lower shape type. (required by cpCollideShapes() )
if(a->klass->type > b->klass->type){
cpShape *temp = a;
a = b;
b = temp;
}
// Narrow-phase collision detection.
cpContact *contacts = cpContactBufferGetArray(space);
int numContacts = cpCollideShapes(a, b, contacts);
if(!numContacts) return; // Shapes are not colliding.
cpSpacePushContacts(space, numContacts);
// Get an arbiter from space->contactSet for the two shapes.
// This is where the persistant contact magic comes from.
cpShape *shape_pair[] = {a, b};
cpHashValue arbHashID = CP_HASH_PAIR((size_t)a, (size_t)b);
cpArbiter *arb = (cpArbiter *)cpHashSetInsert(space->contactSet, arbHashID, shape_pair, space);
cpArbiterUpdate(arb, contacts, numContacts, handler, a, b);
// Call the begin function first if it's the first step
if(arb->state == cpArbiterStateFirstColl && !handler->begin(arb, space, handler->data)){
cpArbiterIgnore(arb); // permanently ignore the collision until separation
}
if(
// Ignore the arbiter if it has been flagged
(arb->state != cpArbiterStateIgnore) &&
// Call preSolve
handler->preSolve(arb, space, handler->data) &&
// Process, but don't add collisions for sensors.
!sensor
){
cpArrayPush(space->arbiters, arb);
} else {
cpSpacePopContacts(space, numContacts);
arb->contacts = NULL;
arb->numContacts = 0;
// Normally arbiters are set as used after calling the post-step callback.
// However, post-step callbacks are not called for sensors or arbiters rejected from pre-solve.
if(arb->state != cpArbiterStateIgnore) arb->state = cpArbiterStateNormal;
}
// Time stamp the arbiter so we know it was used recently.
arb->stamp = space->stamp;
}
void
cpSpaceRemoveCollisionPairFunc(cpSpace *space, unsigned int a, unsigned int b)
{
unsigned int ids[] = {a, b};
unsigned int hash = CP_HASH_PAIR(a, b);
cpCollPairFunc *old_pair = (cpCollPairFunc *)cpHashSetRemove(space->collFuncSet, hash, ids);
free(old_pair);
}
// Callback from the spatial hash.
static void
queryFunc(cpShape *a, cpShape *b, cpSpace *space)
{
// Reject any of the simple cases
if(queryReject(a,b)) return;
// Find the collision pair function for the shapes.
struct{cpCollisionType a, b;} ids = {a->collision_type, b->collision_type};
cpHashValue collHashID = CP_HASH_PAIR(a->collision_type, b->collision_type);
cpCollisionHandler *handler = (cpCollisionHandler *)cpHashSetFind(space->collFuncSet, collHashID, &ids);
int sensor = a->sensor || b->sensor;
if(sensor && handler == &space->defaultHandler) return;
// Shape 'a' should have the lower shape type. (required by cpCollideShapes() )
if(a->klass->type > b->klass->type){
cpShape *temp = a;
a = b;
b = temp;
}
// Narrow-phase collision detection.
cpContact *contacts = NULL;
int numContacts = cpCollideShapes(a, b, &contacts);
if(!numContacts) return; // Shapes are not colliding.
// Get an arbiter from space->contactSet for the two shapes.
// This is where the persistant contact magic comes from.
cpShape *shape_pair[] = {a, b};
cpHashValue arbHashID = CP_HASH_PAIR(a, b);
cpArbiter *arb = (cpArbiter *)cpHashSetInsert(space->contactSet, arbHashID, shape_pair, NULL);
cpArbiterUpdate(arb, contacts, numContacts, handler, a, b); // retains the contacts array
// Call the begin function first if we need to
int beginPass = (arb->stamp >= 0) || (handler->begin(arb, space, handler->data));
if(beginPass && handler->preSolve(arb, space, handler->data) && !sensor){
cpArrayPush(space->arbiters, arb);
} else {
cpfree(arb->contacts);
arb->contacts = NULL;
}
// Time stamp the arbiter so we know it was used recently.
arb->stamp = space->stamp;
}
cpCollisionHandler *
cpSpaceAddWildcardHandler(cpSpace *space, cpCollisionType type)
{
cpSpaceUseWildcardDefaultHandler(space);
cpHashValue hash = CP_HASH_PAIR(type, CP_WILDCARD_COLLISION_TYPE);
cpCollisionHandler handler = {type, CP_WILDCARD_COLLISION_TYPE, AlwaysCollide, AlwaysCollide, DoNothing, DoNothing, NULL};
return (cpCollisionHandler*)cpHashSetInsert(space->collisionHandlers, hash, &handler, (cpHashSetTransFunc)handlerSetTrans, NULL);
}
// Add contacts for probably penetrating vertexes.
// This handles the degenerate case where an overlap was detected, but no vertexes fall inside
// the opposing polygon. (like a star of david)
static /*inline*/ int
findVertsFallback(cpContact *arr, const cpPolyShape *poly1, const cpPolyShape *poly2, const cpVect n, const cpFloat dist)
{
int num = 0;
for(int i=0; i<poly1->numVerts; i++){
cpVect v = poly1->tVerts[i];
if(cpPolyShapeContainsVertPartial(poly2, v, cpvneg(n)))
cpContactInit(nextContactPoint(arr, &num), v, n, dist, CP_HASH_PAIR(poly1->shape.hashid, i));
}
for(int i=0; i<poly2->numVerts; i++){
cpVect v = poly2->tVerts[i];
if(cpPolyShapeContainsVertPartial(poly1, v, n))
cpContactInit(nextContactPoint(arr, &num), v, n, dist, CP_HASH_PAIR(poly2->shape.hashid, i));
}
return num;
}
cpCollisionHandler *cpSpaceAddCollisionHandler(cpSpace *space, cpCollisionType a, cpCollisionType b)
{
cpHashValue hash = CP_HASH_PAIR(a, b);
// TODO should use space->defaultHandler values instead?
cpCollisionHandler temp = {a, b, DefaultBegin, DefaultPreSolve, DefaultPostSolve, DefaultSeparate, NULL};
cpHashSet *handlers = space->collisionHandlers;
cpCollisionHandler *handler = cpHashSetFind(handlers, hash, &temp);
return (handler ? handler : cpHashSetInsert(handlers, hash, &temp, (cpHashSetTransFunc)handlerSetTrans, NULL));
}
// Add contacts for penetrating vertexes.
static inline int
findVerts(cpContact *arr, const cpPolyShape *poly1, const cpPolyShape *poly2, const cpVect n, const cpFloat dist)
{
int num = 0;
for(int i=0; i<poly1->numVerts; i++){
cpVect v = poly1->tVerts[i];
if(cpPolyShapeContainsVert(poly2, v))
cpContactInit(nextContactPoint(arr, &num), v, n, dist, CP_HASH_PAIR(poly1->shape.hashid, i));
}
for(int i=0; i<poly2->numVerts; i++){
cpVect v = poly2->tVerts[i];
if(cpPolyShapeContainsVert(poly1, v))
cpContactInit(nextContactPoint(arr, &num), v, n, dist, CP_HASH_PAIR(poly2->shape.hashid, i));
}
return (num ? num : findVertsFallback(arr, poly1, poly2, n, dist));
}
static struct Edge
SupportEdgeForPoly(const cpPolyShape *poly, const cpVect n)
{
int count = poly->count;
int i1 = PolySupportPointIndex(poly->count, poly->planes, n);
// TODO: get rid of mod eventually, very expensive on ARM
int i0 = (i1 - 1 + count)%count;
int i2 = (i1 + 1)%count;
const struct cpSplittingPlane *planes = poly->planes;
cpHashValue hashid = poly->shape.hashid;
if(cpvdot(n, planes[i1].n) > cpvdot(n, planes[i2].n)) {
struct Edge edge = {{planes[i0].v0, CP_HASH_PAIR(hashid, i0)}, {planes[i1].v0, CP_HASH_PAIR(hashid, i1)}, poly->r, planes[i1].n};
return edge;
} else {
struct Edge edge = {{planes[i1].v0, CP_HASH_PAIR(hashid, i1)}, {planes[i2].v0, CP_HASH_PAIR(hashid, i2)}, poly->r, planes[i2].n};
return edge;
}
}
cpCollisionHandler *
cpSpaceAddWildcardHandler(cpSpace *space, cpCollisionType type)
{
cpSpaceUseWildcardDefaultHandler(space);
cpHashValue hash = CP_HASH_PAIR(type, CP_WILDCARD_COLLISION_TYPE);
cpCollisionHandler temp = {type, CP_WILDCARD_COLLISION_TYPE, AlwaysCollide, AlwaysCollide, DoNothing, DoNothing, NULL};
cpHashSet *handlers = space->collisionHandlers;
cpCollisionHandler *handler = cpHashSetFind(handlers, hash, &temp);
return (handler ? handler : cpHashSetInsert(handlers, hash, &temp, (cpHashSetTransFunc)handlerSetTrans, NULL));
}
void
cpSpaceAddCollisionPairFunc(cpSpace *space, unsigned int a, unsigned int b,
cpCollFunc func, void *data)
{
unsigned int ids[] = {a, b};
unsigned int hash = CP_HASH_PAIR(a, b);
// Remove any old function so the new one will get added.
cpSpaceRemoveCollisionPairFunc(space, a, b);
collFuncData funcData = {func, data};
cpHashSetInsert(space->collFuncSet, hash, ids, &funcData);
}
// Add contacts for penetrating vertexes.
static inline int
findVerts(cpContact *arr, cpPolyShape *poly1, cpPolyShape *poly2, cpVect n, cpFloat dist)
{
int num = 0;
for(int i=0; i<poly1->numVerts; i++){
cpVect v = poly1->tVerts[i];
if(cpPolyShapeContainsVertPartial(poly2, v, cpvneg(n)))
cpContactInit(nextContactPoint(arr, &num), v, n, dist, CP_HASH_PAIR(poly1->shape.hashid, i));
}
for(int i=0; i<poly2->numVerts; i++){
cpVect v = poly2->tVerts[i];
if(cpPolyShapeContainsVertPartial(poly1, v, n))
cpContactInit(nextContactPoint(arr, &num), v, n, dist, CP_HASH_PAIR(poly2->shape.hashid, i));
}
// if(!num)
// addContactPoint(arr, &size, &num, cpContactNew(shape1->body->p, n, dist, 0));
return num;
}
void
cpSpaceActivateBody(cpSpace *space, cpBody *body)
{
cpAssertHard(!cpBodyIsRogue(body), "Internal error: Attempting to activate a rogue body.");
if(space->locked){
// cpSpaceActivateBody() is called again once the space is unlocked
if(!cpArrayContains(space->rousedBodies, body)) cpArrayPush(space->rousedBodies, body);
} else {
cpAssertSoft(body->node.root == NULL && body->node.next == NULL, "Internal error: Activating body non-NULL node pointers.");
cpArrayPush(space->bodies, body);
CP_BODY_FOREACH_SHAPE(body, shape){
cpSpatialIndexRemove(space->staticShapes, shape, shape->hashid);
cpSpatialIndexInsert(space->activeShapes, shape, shape->hashid);
}
CP_BODY_FOREACH_ARBITER(body, arb){
cpBody *bodyA = arb->body_a;
// Arbiters are shared between two bodies that are always woken up together.
// You only want to restore the arbiter once, so bodyA is arbitrarily chosen to own the arbiter.
// The edge case is when static bodies are involved as the static bodies never actually sleep.
// If the static body is bodyB then all is good. If the static body is bodyA, that can easily be checked.
if(body == bodyA || cpBodyIsStatic(bodyA)){
int numContacts = arb->numContacts;
cpContact *contacts = arb->contacts;
// Restore contact values back to the space's contact buffer memory
arb->contacts = cpContactBufferGetArray(space);
memcpy(arb->contacts, contacts, numContacts*sizeof(cpContact));
cpSpacePushContacts(space, numContacts);
// Reinsert the arbiter into the arbiter cache
cpShape *a = arb->a, *b = arb->b;
cpShape *shape_pair[] = {a, b};
cpHashValue arbHashID = CP_HASH_PAIR((cpHashValue)a, (cpHashValue)b);
cpHashSetInsert(space->cachedArbiters, arbHashID, shape_pair, arb, NULL);
// Update the arbiter's state
arb->stamp = space->stamp;
arb->handler = cpSpaceLookupHandler(space, a->collision_type, b->collision_type);
cpArrayPush(space->arbiters, arb);
cpfree(contacts);
}
}
// Identify vertexes that have penetrated the segment.
static inline void
findPointsBehindSeg(cpContact **arr, int *max, int *num, cpSegmentShape *seg, cpPolyShape *poly, cpFloat pDist, cpFloat coef)
{
cpFloat dta = cpvcross(seg->tn, seg->ta);
cpFloat dtb = cpvcross(seg->tn, seg->tb);
cpVect n = cpvmult(seg->tn, coef);
for(int i=0; i<poly->numVerts; i++){
cpVect v = poly->tVerts[i];
if(cpvdot(v, n) < cpvdot(seg->tn, seg->ta)*coef + seg->r){
cpFloat dt = cpvcross(seg->tn, v);
if(dta >= dt && dt >= dtb){
cpContactInit(addContactPoint(arr, max, num), v, n, pDist, CP_HASH_PAIR(poly->shape.hashid, i));
}
}
}
}
void
cpSpaceActivateBody(cpSpace *space, cpBody *body)
{
cpAssertHard(!cpBodyIsRogue(body), "Internal error: Attempting to activate a rouge body.");
if(space->locked){
// cpSpaceActivateBody() is called again once the space is unlocked
if(!cpArrayContains(space->rousedBodies, body)) cpArrayPush(space->rousedBodies, body);
} else {
cpArrayPush(space->bodies, body);
CP_BODY_FOREACH_SHAPE(body, shape){
cpSpatialIndexRemove(space->staticShapes, shape, shape->hashid);
cpSpatialIndexInsert(space->activeShapes, shape, shape->hashid);
}
CP_BODY_FOREACH_ARBITER(body, arb){
cpBody *bodyA = arb->body_a;
if(body == bodyA || cpBodyIsStatic(bodyA)){
int numContacts = arb->numContacts;
cpContact *contacts = arb->contacts;
// Restore contact values back to the space's contact buffer memory
arb->contacts = cpContactBufferGetArray(space);
memcpy(arb->contacts, contacts, numContacts*sizeof(cpContact));
cpSpacePushContacts(space, numContacts);
// Reinsert the arbiter into the arbiter cache
cpShape *a = arb->a, *b = arb->b;
cpShape *shape_pair[] = {a, b};
cpHashValue arbHashID = CP_HASH_PAIR((cpHashValue)a, (cpHashValue)b);
cpHashSetInsert(space->cachedArbiters, arbHashID, shape_pair, arb, NULL);
// Update the arbiter's state
arb->stamp = space->stamp;
arb->handler = cpSpaceLookupHandler(space, a->collision_type, b->collision_type);
cpArrayPush(space->arbiters, arb);
cpfree(contacts);
}
}
static inline cpCollisionHandler *
cpSpaceLookupHandler(cpSpace *space, cpCollisionType a, cpCollisionType b, cpCollisionHandler *defaultValue)
{
cpCollisionType types[] = {a, b};
cpCollisionHandler *handler = (cpCollisionHandler *)cpHashSetFind(space->collisionHandlers, CP_HASH_PAIR(a, b), types);
return (handler ? handler : defaultValue);
}
// Callback from the spatial hash.
static void
queryFunc(cpShape *a, cpShape *b, cpSpace *space)
{
// Reject any of the simple cases
if(queryReject(a,b)) return;
// Find the collision pair function for the shapes.
struct{cpCollisionType a, b;} ids = {a->collision_type, b->collision_type};
cpHashValue collHashID = CP_HASH_PAIR(a->collision_type, b->collision_type);
cpCollisionHandler *handler = (cpCollisionHandler *)cpHashSetFind(space->collFuncSet, collHashID, &ids);
int sensor = a->sensor || b->sensor;
if(sensor && handler == &space->defaultHandler) return;
// Shape 'a' should have the lower shape type. (required by cpCollideShapes() )
if(a->klass->type > b->klass->type){
cpShape *temp = a;
a = b;
b = temp;
}
if(space->contactBuffersHead->numContacts + CP_MAX_CONTACTS_PER_ARBITER > CP_CONTACTS_BUFFER_SIZE){
// contact buffer could overflow on the next collision, push a fresh one.
cpSpacePushNewContactBuffer(space);
}
// Narrow-phase collision detection.
cpContact *contacts = ((cpContactBuffer *)(space->contactBuffersHead))->contacts + space->contactBuffersHead->numContacts;
int numContacts = cpCollideShapes(a, b, contacts);
if(!numContacts) return; // Shapes are not colliding.
space->contactBuffersHead->numContacts += numContacts;
// Get an arbiter from space->contactSet for the two shapes.
// This is where the persistant contact magic comes from.
cpShape *shape_pair[] = {a, b};
cpHashValue arbHashID = CP_HASH_PAIR((size_t)a, (size_t)b);
cpArbiter *arb = (cpArbiter *)cpHashSetInsert(space->contactSet, arbHashID, shape_pair, space);
cpArbiterUpdate(arb, contacts, numContacts, handler, a, b); // retains the contacts array
// Call the begin function first if it's the first step
if(arb->stamp == -1 && !handler->begin(arb, space, handler->data)){
cpArbiterIgnore(arb); // permanently ignore the collision until separation
}
if(
// Ignore the arbiter if it has been flagged
(arb->state != cpArbiterStateIgnore) &&
// Call preSolve
handler->preSolve(arb, space, handler->data) &&
// Process, but don't add collisions for sensors.
!sensor
){
cpArrayPush(space->arbiters, arb);
} else {
// cpfree(arb->contacts);
space->contactBuffersHead->numContacts -= numContacts;
arb->contacts = NULL;
arb->numContacts = 0;
}
// Time stamp the arbiter so we know it was used recently.
arb->stamp = space->stamp;
}
void
cpSpaceRemoveCollisionHandler(cpSpace *space, cpCollisionType a, cpCollisionType b)
{
cpAssertSpaceUnlocked(space);
struct { cpCollisionType a, b; } ids = {a, b};
cpCollisionHandler *old_handler = (cpCollisionHandler *) cpHashSetRemove(space->collisionHandlers, CP_HASH_PAIR(a, b), &ids);
cpfree(old_handler);
}
cpCollisionHandler *cpSpaceAddCollisionHandler(cpSpace *space, cpCollisionType a, cpCollisionType b)
{
cpHashValue hash = CP_HASH_PAIR(a, b);
cpCollisionHandler handler = {a, b, DefaultBegin, DefaultPreSolve, DefaultPostSolve, DefaultSeparate, NULL};
return (cpCollisionHandler*)cpHashSetInsert(space->collisionHandlers, hash, &handler, (cpHashSetTransFunc)handlerSetTrans, NULL);
}
// Callback from the spatial hash.
// TODO: Refactor this into separate functions?
static int
queryFunc(void *p1, void *p2, void *data)
{
// Cast the generic pointers from the spatial hash back to usefull types
cpShape *a = (cpShape *)p1;
cpShape *b = (cpShape *)p2;
cpSpace *space = (cpSpace *)data;
// Reject any of the simple cases
if(queryReject(a,b)) return 0;
// Shape 'a' should have the lower shape type. (required by cpCollideShapes() )
if(a->klass->type > b->klass->type){
cpShape *temp = a;
a = b;
b = temp;
}
// Find the collision pair function for the shapes.
unsigned int ids[] = {a->collision_type, b->collision_type};
unsigned int hash = CP_HASH_PAIR(a->collision_type, b->collision_type);
cpCollPairFunc *pairFunc = (cpCollPairFunc *)cpHashSetFind(space->collFuncSet, hash, ids);
if(!pairFunc->func) return 0; // A NULL pair function means don't collide at all.
// Narrow-phase collision detection.
cpContact *contacts = NULL;
int numContacts = cpCollideShapes(a, b, &contacts);
if(!numContacts) return 0; // Shapes are not colliding.
// The collision pair function requires objects to be ordered by their collision types.
cpShape *pair_a = a;
cpShape *pair_b = b;
cpFloat normal_coef = 1.0f;
// Swap them if necessary.
if(pair_a->collision_type != pairFunc->a){
cpShape *temp = pair_a;
pair_a = pair_b;
pair_b = temp;
normal_coef = -1.0f;
}
if(pairFunc->func(pair_a, pair_b, contacts, numContacts, normal_coef, pairFunc->data)){
// The collision pair function OKed the collision. Record the contact information.
// Get an arbiter from space->contactSet for the two shapes.
// This is where the persistant contact magic comes from.
cpShape *shape_pair[] = {a, b};
cpArbiter *arb = (cpArbiter *)cpHashSetInsert(space->contactSet, CP_HASH_PAIR(a, b), shape_pair, space);
// Timestamp the arbiter.
arb->stamp = space->stamp;
arb->a = a; arb->b = b; // TODO: Investigate why this is still necessary?
// Inject the new contact points into the arbiter.
cpArbiterInject(arb, contacts, numContacts);
// Add the arbiter to the list of active arbiters.
cpArrayPush(space->arbiters, arb);
return numContacts;
} else {
// The collision pair function rejected the collision.
free(contacts);
return 0;
}
}
unsigned int bmx_CP_HASH_PAIR(int collTypeA, int collTypeB) {
return CP_HASH_PAIR(collTypeA, collTypeB);
}
static /*inline*/ cpCollisionHandler *
lookupCollisionHandler(cpSpace *space, cpCollisionType a, cpCollisionType b)
{
cpCollisionType types[] = {a, b};
return (cpCollisionHandler *)cpHashSetFind(space->collFuncSet, CP_HASH_PAIR(a, b), types);
}
