prosperon/source/engine/thirdparty/Chipmunk2D/src/cpBody.c
2022-01-25 15:22:03 +00:00

627 lines
14 KiB
C
Executable file

/* Copyright (c) 2013 Scott Lembcke and Howling Moon Software
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
* SOFTWARE.
*/
#include <float.h>
#include <stdarg.h>
#include "chipmunk/chipmunk_private.h"
cpBody*
cpBodyAlloc(void)
{
return (cpBody *)cpcalloc(1, sizeof(cpBody));
}
cpBody *
cpBodyInit(cpBody *body, cpFloat mass, cpFloat moment)
{
body->space = NULL;
body->shapeList = NULL;
body->arbiterList = NULL;
body->constraintList = NULL;
body->velocity_func = cpBodyUpdateVelocity;
body->position_func = cpBodyUpdatePosition;
body->sleeping.root = NULL;
body->sleeping.next = NULL;
body->sleeping.idleTime = 0.0f;
body->p = cpvzero;
body->v = cpvzero;
body->f = cpvzero;
body->w = 0.0f;
body->t = 0.0f;
body->v_bias = cpvzero;
body->w_bias = 0.0f;
body->userData = NULL;
// Setters must be called after full initialization so the sanity checks don't assert on garbage data.
cpBodySetMass(body, mass);
cpBodySetMoment(body, moment);
cpBodySetAngle(body, 0.0f);
return body;
}
cpBody*
cpBodyNew(cpFloat mass, cpFloat moment)
{
return cpBodyInit(cpBodyAlloc(), mass, moment);
}
cpBody*
cpBodyNewKinematic()
{
cpBody *body = cpBodyNew(0.0f, 0.0f);
cpBodySetType(body, CP_BODY_TYPE_KINEMATIC);
return body;
}
cpBody*
cpBodyNewStatic()
{
cpBody *body = cpBodyNew(0.0f, 0.0f);
cpBodySetType(body, CP_BODY_TYPE_STATIC);
return body;
}
void cpBodyDestroy(cpBody *body){}
void
cpBodyFree(cpBody *body)
{
if(body){
cpBodyDestroy(body);
cpfree(body);
}
}
#ifdef NDEBUG
#define cpAssertSaneBody(body)
#else
static void cpv_assert_nan(cpVect v, char *message){cpAssertHard(v.x == v.x && v.y == v.y, message);}
static void cpv_assert_infinite(cpVect v, char *message){cpAssertHard(cpfabs(v.x) != INFINITY && cpfabs(v.y) != INFINITY, message);}
static void cpv_assert_sane(cpVect v, char *message){cpv_assert_nan(v, message); cpv_assert_infinite(v, message);}
static void
cpBodySanityCheck(const cpBody *body)
{
cpAssertHard(body->m == body->m && body->m_inv == body->m_inv, "Body's mass is NaN.");
cpAssertHard(body->i == body->i && body->i_inv == body->i_inv, "Body's moment is NaN.");
cpAssertHard(body->m >= 0.0f, "Body's mass is negative.");
cpAssertHard(body->i >= 0.0f, "Body's moment is negative.");
cpv_assert_sane(body->p, "Body's position is invalid.");
cpv_assert_sane(body->v, "Body's velocity is invalid.");
cpv_assert_sane(body->f, "Body's force is invalid.");
cpAssertHard(body->a == body->a && cpfabs(body->a) != INFINITY, "Body's angle is invalid.");
cpAssertHard(body->w == body->w && cpfabs(body->w) != INFINITY, "Body's angular velocity is invalid.");
cpAssertHard(body->t == body->t && cpfabs(body->t) != INFINITY, "Body's torque is invalid.");
}
#define cpAssertSaneBody(body) cpBodySanityCheck(body)
#endif
cpBool
cpBodyIsSleeping(const cpBody *body)
{
return (body->sleeping.root != ((cpBody*)0));
}
cpBodyType
cpBodyGetType(cpBody *body)
{
if(body->sleeping.idleTime == INFINITY){
return CP_BODY_TYPE_STATIC;
} else if(body->m == INFINITY){
return CP_BODY_TYPE_KINEMATIC;
} else {
return CP_BODY_TYPE_DYNAMIC;
}
}
void
cpBodySetType(cpBody *body, cpBodyType type)
{
cpBodyType oldType = cpBodyGetType(body);
if(oldType == type) return;
// Static bodies have their idle timers set to infinity.
// Non-static bodies should have their idle timer reset.
body->sleeping.idleTime = (type == CP_BODY_TYPE_STATIC ? INFINITY : 0.0f);
if(type == CP_BODY_TYPE_DYNAMIC){
body->m = body->i = 0.0f;
body->m_inv = body->i_inv = INFINITY;
cpBodyAccumulateMassFromShapes(body);
} else {
body->m = body->i = INFINITY;
body->m_inv = body->i_inv = 0.0f;
body->v = cpvzero;
body->w = 0.0f;
}
// If the body is added to a space already, we'll need to update some space data structures.
cpSpace *space = cpBodyGetSpace(body);
if(space != NULL){
cpAssertSpaceUnlocked(space);
if(oldType == CP_BODY_TYPE_STATIC){
// TODO This is probably not necessary
// cpBodyActivateStatic(body, NULL);
} else {
cpBodyActivate(body);
}
// Move the bodies to the correct array.
cpArray *fromArray = cpSpaceArrayForBodyType(space, oldType);
cpArray *toArray = cpSpaceArrayForBodyType(space, type);
if(fromArray != toArray){
cpArrayDeleteObj(fromArray, body);
cpArrayPush(toArray, body);
}
// Move the body's shapes to the correct spatial index.
cpSpatialIndex *fromIndex = (oldType == CP_BODY_TYPE_STATIC ? space->staticShapes : space->dynamicShapes);
cpSpatialIndex *toIndex = (type == CP_BODY_TYPE_STATIC ? space->staticShapes : space->dynamicShapes);
if(fromIndex != toIndex){
CP_BODY_FOREACH_SHAPE(body, shape){
cpSpatialIndexRemove(fromIndex, shape, shape->hashid);
cpSpatialIndexInsert(toIndex, shape, shape->hashid);
}
}
}
}
// Should *only* be called when shapes with mass info are modified, added or removed.
void
cpBodyAccumulateMassFromShapes(cpBody *body)
{
if(body == NULL || cpBodyGetType(body) != CP_BODY_TYPE_DYNAMIC) return;
// Reset the body's mass data.
body->m = body->i = 0.0f;
body->cog = cpvzero;
// Cache the position to realign it at the end.
cpVect pos = cpBodyGetPosition(body);
// Accumulate mass from shapes.
CP_BODY_FOREACH_SHAPE(body, shape){
struct cpShapeMassInfo *info = &shape->massInfo;
cpFloat m = info->m;
if(m > 0.0f){
cpFloat msum = body->m + m;
body->i += m*info->i + cpvdistsq(body->cog, info->cog)*(m*body->m)/msum;
body->cog = cpvlerp(body->cog, info->cog, m/msum);
body->m = msum;
}
}
// Recalculate the inverses.
body->m_inv = 1.0f/body->m;
body->i_inv = 1.0f/body->i;
// Realign the body since the CoG has probably moved.
cpBodySetPosition(body, pos);
cpAssertSaneBody(body);
}
cpSpace *
cpBodyGetSpace(const cpBody *body)
{
return body->space;
}
cpFloat
cpBodyGetMass(const cpBody *body)
{
return body->m;
}
void
cpBodySetMass(cpBody *body, cpFloat mass)
{
cpAssertHard(cpBodyGetType(body) == CP_BODY_TYPE_DYNAMIC, "You cannot set the mass of kinematic or static bodies.");
cpAssertHard(0.0f <= mass && mass < INFINITY, "Mass must be positive and finite.");
cpBodyActivate(body);
body->m = mass;
body->m_inv = mass == 0.0f ? INFINITY : 1.0f/mass;
cpAssertSaneBody(body);
}
cpFloat
cpBodyGetMoment(const cpBody *body)
{
return body->i;
}
void
cpBodySetMoment(cpBody *body, cpFloat moment)
{
cpAssertHard(moment >= 0.0f, "Moment of Inertia must be positive.");
cpBodyActivate(body);
body->i = moment;
body->i_inv = moment == 0.0f ? INFINITY : 1.0f/moment;
cpAssertSaneBody(body);
}
cpVect
cpBodyGetRotation(const cpBody *body)
{
return cpv(body->transform.a, body->transform.b);
}
void
cpBodyAddShape(cpBody *body, cpShape *shape)
{
cpShape *next = body->shapeList;
if(next) next->prev = shape;
shape->next = next;
body->shapeList = shape;
if(shape->massInfo.m > 0.0f){
cpBodyAccumulateMassFromShapes(body);
}
}
void
cpBodyRemoveShape(cpBody *body, cpShape *shape)
{
cpShape *prev = shape->prev;
cpShape *next = shape->next;
if(prev){
prev->next = next;
} else {
body->shapeList = next;
}
if(next){
next->prev = prev;
}
shape->prev = NULL;
shape->next = NULL;
if(cpBodyGetType(body) == CP_BODY_TYPE_DYNAMIC && shape->massInfo.m > 0.0f){
cpBodyAccumulateMassFromShapes(body);
}
}
static cpConstraint *
filterConstraints(cpConstraint *node, cpBody *body, cpConstraint *filter)
{
if(node == filter){
return cpConstraintNext(node, body);
} else if(node->a == body){
node->next_a = filterConstraints(node->next_a, body, filter);
} else {
node->next_b = filterConstraints(node->next_b, body, filter);
}
return node;
}
void
cpBodyRemoveConstraint(cpBody *body, cpConstraint *constraint)
{
body->constraintList = filterConstraints(body->constraintList, body, constraint);
}
// 'p' is the position of the CoG
static void
SetTransform(cpBody *body, cpVect p, cpFloat a)
{
cpVect rot = cpvforangle(a);
cpVect c = body->cog;
body->transform = cpTransformNewTranspose(
rot.x, -rot.y, p.x - (c.x*rot.x - c.y*rot.y),
rot.y, rot.x, p.y - (c.x*rot.y + c.y*rot.x)
);
}
static inline cpFloat
SetAngle(cpBody *body, cpFloat a)
{
body->a = a;
cpAssertSaneBody(body);
return a;
}
cpVect
cpBodyGetPosition(const cpBody *body)
{
return cpTransformPoint(body->transform, cpvzero);
}
void
cpBodySetPosition(cpBody *body, cpVect position)
{
cpBodyActivate(body);
cpVect p = body->p = cpvadd(cpTransformVect(body->transform, body->cog), position);
cpAssertSaneBody(body);
SetTransform(body, p, body->a);
}
cpVect
cpBodyGetCenterOfGravity(const cpBody *body)
{
return body->cog;
}
void
cpBodySetCenterOfGravity(cpBody *body, cpVect cog)
{
cpBodyActivate(body);
body->cog = cog;
cpAssertSaneBody(body);
}
cpVect
cpBodyGetVelocity(const cpBody *body)
{
return body->v;
}
void
cpBodySetVelocity(cpBody *body, cpVect velocity)
{
cpBodyActivate(body);
body->v = velocity;
cpAssertSaneBody(body);
}
cpVect
cpBodyGetForce(const cpBody *body)
{
return body->f;
}
void
cpBodySetForce(cpBody *body, cpVect force)
{
cpBodyActivate(body);
body->f = force;
cpAssertSaneBody(body);
}
cpFloat
cpBodyGetAngle(const cpBody *body)
{
return body->a;
}
void
cpBodySetAngle(cpBody *body, cpFloat angle)
{
cpBodyActivate(body);
SetAngle(body, angle);
SetTransform(body, body->p, angle);
}
cpFloat
cpBodyGetAngularVelocity(const cpBody *body)
{
return body->w;
}
void
cpBodySetAngularVelocity(cpBody *body, cpFloat angularVelocity)
{
cpBodyActivate(body);
body->w = angularVelocity;
cpAssertSaneBody(body);
}
cpFloat
cpBodyGetTorque(const cpBody *body)
{
return body->t;
}
void
cpBodySetTorque(cpBody *body, cpFloat torque)
{
cpBodyActivate(body);
body->t = torque;
cpAssertSaneBody(body);
}
cpDataPointer
cpBodyGetUserData(const cpBody *body)
{
return body->userData;
}
void
cpBodySetUserData(cpBody *body, cpDataPointer userData)
{
body->userData = userData;
}
void
cpBodySetVelocityUpdateFunc(cpBody *body, cpBodyVelocityFunc velocityFunc)
{
body->velocity_func = velocityFunc;
}
void
cpBodySetPositionUpdateFunc(cpBody *body, cpBodyPositionFunc positionFunc)
{
body->position_func = positionFunc;
}
void
cpBodyUpdateVelocity(cpBody *body, cpVect gravity, cpFloat damping, cpFloat dt)
{
// Skip kinematic bodies.
if(cpBodyGetType(body) == CP_BODY_TYPE_KINEMATIC) return;
cpAssertSoft(body->m > 0.0f && body->i > 0.0f, "Body's mass and moment must be positive to simulate. (Mass: %f Moment: %f)", body->m, body->i);
body->v = cpvadd(cpvmult(body->v, damping), cpvmult(cpvadd(gravity, cpvmult(body->f, body->m_inv)), dt));
body->w = body->w*damping + body->t*body->i_inv*dt;
// Reset forces.
body->f = cpvzero;
body->t = 0.0f;
cpAssertSaneBody(body);
}
void
cpBodyUpdatePosition(cpBody *body, cpFloat dt)
{
cpVect p = body->p = cpvadd(body->p, cpvmult(cpvadd(body->v, body->v_bias), dt));
cpFloat a = SetAngle(body, body->a + (body->w + body->w_bias)*dt);
SetTransform(body, p, a);
body->v_bias = cpvzero;
body->w_bias = 0.0f;
cpAssertSaneBody(body);
}
cpVect
cpBodyLocalToWorld(const cpBody *body, const cpVect point)
{
return cpTransformPoint(body->transform, point);
}
cpVect
cpBodyWorldToLocal(const cpBody *body, const cpVect point)
{
return cpTransformPoint(cpTransformRigidInverse(body->transform), point);
}
void
cpBodyApplyForceAtWorldPoint(cpBody *body, cpVect force, cpVect point)
{
cpBodyActivate(body);
body->f = cpvadd(body->f, force);
cpVect r = cpvsub(point, cpTransformPoint(body->transform, body->cog));
body->t += cpvcross(r, force);
}
void
cpBodyApplyForceAtLocalPoint(cpBody *body, cpVect force, cpVect point)
{
cpBodyApplyForceAtWorldPoint(body, cpTransformVect(body->transform, force), cpTransformPoint(body->transform, point));
}
void
cpBodyApplyImpulseAtWorldPoint(cpBody *body, cpVect impulse, cpVect point)
{
cpBodyActivate(body);
cpVect r = cpvsub(point, cpTransformPoint(body->transform, body->cog));
apply_impulse(body, impulse, r);
}
void
cpBodyApplyImpulseAtLocalPoint(cpBody *body, cpVect impulse, cpVect point)
{
cpBodyApplyImpulseAtWorldPoint(body, cpTransformVect(body->transform, impulse), cpTransformPoint(body->transform, point));
}
cpVect
cpBodyGetVelocityAtLocalPoint(const cpBody *body, cpVect point)
{
cpVect r = cpTransformVect(body->transform, cpvsub(point, body->cog));
return cpvadd(body->v, cpvmult(cpvperp(r), body->w));
}
cpVect
cpBodyGetVelocityAtWorldPoint(const cpBody *body, cpVect point)
{
cpVect r = cpvsub(point, cpTransformPoint(body->transform, body->cog));
return cpvadd(body->v, cpvmult(cpvperp(r), body->w));
}
cpFloat
cpBodyKineticEnergy(const cpBody *body)
{
// Need to do some fudging to avoid NaNs
cpFloat vsq = cpvdot(body->v, body->v);
cpFloat wsq = body->w*body->w;
return (vsq ? vsq*body->m : 0.0f) + (wsq ? wsq*body->i : 0.0f);
}
void
cpBodyEachShape(cpBody *body, cpBodyShapeIteratorFunc func, void *data)
{
cpShape *shape = body->shapeList;
while(shape){
cpShape *next = shape->next;
func(body, shape, data);
shape = next;
}
}
void
cpBodyEachConstraint(cpBody *body, cpBodyConstraintIteratorFunc func, void *data)
{
cpConstraint *constraint = body->constraintList;
while(constraint){
cpConstraint *next = cpConstraintNext(constraint, body);
func(body, constraint, data);
constraint = next;
}
}
void
cpBodyEachArbiter(cpBody *body, cpBodyArbiterIteratorFunc func, void *data)
{
cpArbiter *arb = body->arbiterList;
while(arb){
cpArbiter *next = cpArbiterNext(arb, body);
cpBool swapped = arb->swapped; {
arb->swapped = (body == arb->body_b);
func(body, arb, data);
} arb->swapped = swapped;
arb = next;
}
}