public Test(){
Vec2 gravity = new Vec2();
gravity.Set(0.0f, -10.0f);
m_world = new World(gravity);
m_bomb = null;
m_textLine = 30;
m_mouseJoint = null;
m_pointCount = 0;
m_debugDraw = new DebugDraw();
m_destructionListener = new TestDestructionListener();
m_destructionListener.test = this;
m_world.SetDestructionListener(m_destructionListener);
m_world.SetContactListener(this);
m_world.SetDebugDraw(m_debugDraw);
m_bombSpawning = false;
m_stepCount = 0;
BodyDef bodyDef = new BodyDef();
m_groundBody = m_world.CreateBody(bodyDef);
m_maxProfile = new Profile();
m_totalProfile = new Profile();
}
/// Construct a world object.
/// @param gravity the world gravity vector.
public World(Vec2 gravity){
m_destructionListener = null;
m_debugDraw = null;
m_bodyList = new List<Body>();
m_jointList = new List<Joint>();
m_warmStarting = true;
m_continuousPhysics = true;
m_subStepping = false;
m_stepComplete = true;
m_allowSleep = true;
m_gravity = gravity;
m_flags = WorldFlags.e_clearForces;
m_inv_dt0 = 0.0f;
m_profile = new Profile();
m_contactManager = new ContactManager();
}
public virtual void Step(TestSettings settings) {
float timeStep = settings.hz > 0.0f ? 1.0f / settings.hz : 0.0f;
if (settings.pause)
{
if (settings.singleStep)
{
settings.singleStep = false;
}
else
{
timeStep = 0.0f;
}
m_debugDraw.DrawString("****PAUSED****");
}
Draw.DrawFlags flags = 0;
flags |= settings.drawShapes ? Draw.DrawFlags.e_shapeBit : 0;
flags |= settings.drawJoints ? Draw.DrawFlags.e_jointBit : 0;
flags |= settings.drawAABBs ? Draw.DrawFlags.e_aabbBit : 0;
flags |= settings.drawCOMs ? Draw.DrawFlags.e_centerOfMassBit : 0;
m_debugDraw.SetFlags(flags);
m_world.SetAllowSleeping(settings.enableSleep);
m_world.SetWarmStarting(settings.enableWarmStarting);
m_world.SetContinuousPhysics(settings.enableContinuous);
m_world.SetSubStepping(settings.enableSubStepping);
m_pointCount = 0;
m_world.Step(timeStep, settings.velocityIterations, settings.positionIterations);
m_world.DrawDebugData();
if (timeStep > 0.0f)
{
++m_stepCount;
}
if (settings.drawStats)
{
int bodyCount = m_world.GetBodyCount();
int contactCount = m_world.GetContactCount();
int jointCount = m_world.GetJointCount();
m_debugDraw.DrawString("bodies/contacts/joints = {0}/{1}/{2}", bodyCount, contactCount, jointCount);
int proxyCount = m_world.GetProxyCount();
int height = m_world.GetTreeHeight();
int balance = m_world.GetTreeBalance();
float quality = m_world.GetTreeQuality();
m_debugDraw.DrawString("proxies/height/balance/quality = {0}/{1}/{2}/{3}", proxyCount, height, balance, quality);
}
// Track maximum profile times
{
Profile p = m_world.GetProfile();
m_maxProfile.step = Math.Max(m_maxProfile.step, p.step);
m_maxProfile.collide = Math.Max(m_maxProfile.collide, p.collide);
m_maxProfile.solve = Math.Max(m_maxProfile.solve, p.solve);
m_maxProfile.solveInit = Math.Max(m_maxProfile.solveInit, p.solveInit);
m_maxProfile.solveVelocity = Math.Max(m_maxProfile.solveVelocity, p.solveVelocity);
m_maxProfile.solvePosition = Math.Max(m_maxProfile.solvePosition, p.solvePosition);
m_maxProfile.solveTOI = Math.Max(m_maxProfile.solveTOI, p.solveTOI);
m_maxProfile.broadphase = Math.Max(m_maxProfile.broadphase, p.broadphase);
m_totalProfile.step += p.step;
m_totalProfile.collide += p.collide;
m_totalProfile.solve += p.solve;
m_totalProfile.solveInit += p.solveInit;
m_totalProfile.solveVelocity += p.solveVelocity;
m_totalProfile.solvePosition += p.solvePosition;
m_totalProfile.solveTOI += p.solveTOI;
m_totalProfile.broadphase += p.broadphase;
}
if (settings.drawProfile)
{
Profile p = m_world.GetProfile();
Profile aveProfile = new Profile();
if (m_stepCount > 0)
{
float scale = 1.0f / m_stepCount;
aveProfile.step = scale * m_totalProfile.step;
aveProfile.collide = scale * m_totalProfile.collide;
aveProfile.solve = scale * m_totalProfile.solve;
aveProfile.solveInit = scale * m_totalProfile.solveInit;
aveProfile.solveVelocity = scale * m_totalProfile.solveVelocity;
aveProfile.solvePosition = scale * m_totalProfile.solvePosition;
aveProfile.solveTOI = scale * m_totalProfile.solveTOI;
aveProfile.broadphase = scale * m_totalProfile.broadphase;
}
m_debugDraw.DrawString("step [ave] (max) = %5.2f [%6.2f] (%6.2f)", p.step, aveProfile.step, m_maxProfile.step);
m_debugDraw.DrawString("collide [ave] (max) = %5.2f [%6.2f] (%6.2f)", p.collide, aveProfile.collide, m_maxProfile.collide);
m_debugDraw.DrawString("solve [ave] (max) = %5.2f [%6.2f] (%6.2f)", p.solve, aveProfile.solve, m_maxProfile.solve);
m_debugDraw.DrawString("solve init [ave] (max) = %5.2f [%6.2f] (%6.2f)", p.solveInit, aveProfile.solveInit, m_maxProfile.solveInit);
m_debugDraw.DrawString("solve velocity [ave] (max) = %5.2f [%6.2f] (%6.2f)", p.solveVelocity, aveProfile.solveVelocity, m_maxProfile.solveVelocity);
m_debugDraw.DrawString("solve position [ave] (max) = %5.2f [%6.2f] (%6.2f)", p.solvePosition, aveProfile.solvePosition, m_maxProfile.solvePosition);
m_debugDraw.DrawString("solveTOI [ave] (max) = %5.2f [%6.2f] (%6.2f)", p.solveTOI, aveProfile.solveTOI, m_maxProfile.solveTOI);
m_debugDraw.DrawString("broad-phase [ave] (max) = %5.2f [%6.2f] (%6.2f)", p.broadphase, aveProfile.broadphase, m_maxProfile.broadphase);
}
if (m_mouseJoint != null)
{
Vec2 p1 = m_mouseJoint.GetAnchorB();
Vec2 p2 = m_mouseJoint.GetTarget();
Color c = Color.FromArgb(0, 255, 0);
m_debugDraw.DrawPoint(p1, 4.0f, c);
m_debugDraw.DrawPoint(p2, 4.0f, c);
c = Color.FromArgb(204, 204, 204);
m_debugDraw.DrawSegment(p1, p2, c);
}
if (m_bombSpawning)
{
Color c = Color.FromArgb(0, 0, 255);
m_debugDraw.DrawPoint(m_bombSpawnPoint, 4.0f, c);
c = Color.FromArgb(200, 200, 200);
m_debugDraw.DrawSegment(m_mouseWorld, m_bombSpawnPoint, c);
}
if (settings.drawContactPoints)
{
const float k_impulseScale = 0.1f;
const float k_axisScale = 0.3f;
for (int i = 0; i < m_pointCount; ++i)
{
ContactPoint point = m_points[i];
if (point.state == PointState._addState)
{
// Add
m_debugDraw.DrawPoint(point.position, 10.0f, Color.FromArgb(75, 242, 75));
}
else if (point.state == PointState._persistState)
{
// Persist
m_debugDraw.DrawPoint(point.position, 5.0f, Color.FromArgb(75, 75, 242));
}
if (settings.drawContactNormals)
{
Vec2 p1 = point.position;
Vec2 p2 = p1 + k_axisScale * point.normal;
m_debugDraw.DrawSegment(p1, p2, Color.FromArgb(242, 242, 242));
}
else if (settings.drawContactImpulse)
{
Vec2 p1 = point.position;
Vec2 p2 = p1 + k_impulseScale * point.normalImpulse * point.normal;
m_debugDraw.DrawSegment(p1, p2, Color.FromArgb(242, 242, 75));
}
if (settings.drawFrictionImpulse)
{
Vec2 tangent = Utilities.Cross(point.normal, 1.0f);
Vec2 p1 = point.position;
Vec2 p2 = p1 + k_impulseScale * point.tangentImpulse * tangent;
m_debugDraw.DrawSegment(p1, p2, Color.FromArgb(242, 242, 75));
}
}
}
}
private void Solve(TimeStep step){
m_profile.solveInit = 0.0f;
m_profile.solveVelocity = 0.0f;
m_profile.solvePosition = 0.0f;
// Size the island for the worst case.
Island island = new Island(m_contactManager.m_contactListener);
// Clear all the island flags.
foreach (Body b in m_bodyList)
{
b.m_flags &= ~Body.BodyFlags.e_islandFlag;
}
foreach (Contact c in m_contactManager.m_contactList)
{
c.m_flags &= ~ContactFlags.e_islandFlag;
}
foreach (Joint j in m_jointList)
{
j.m_islandFlag = false;
}
// Build and simulate all awake islands.
List<Body> stack = new List<Body>(m_bodyList.Count());
foreach (Body seed in m_bodyList)
{
if (seed.m_flags.HasFlag(Body.BodyFlags.e_islandFlag))
{
continue;
}
if (seed.IsAwake() == false || seed.IsActive() == false)
{
continue;
}
// The seed can be dynamic or kinematic.
if (seed.GetBodyType() == BodyType._staticBody)
{
continue;
}
// Reset island and stack.
island.Clear();
int stackCount = 0;
stack.Add(seed); stackCount++;
seed.m_flags |= Body.BodyFlags.e_islandFlag;
// Perform a depth first search (DFS) on the constraint graph.
while (stackCount > 0)
{
// Grab the next body off the stack and add it to the island.
Body b = stack[--stackCount];
Utilities.Assert(b.IsActive() == true);
island.Add(b);
// Make sure the body is awake.
b.SetAwake(true);
// To keep islands as small as possible, we don't
// propagate islands across static bodies.
if (b.GetBodyType() == BodyType._staticBody)
{
continue;
}
// Search all contacts connected to this body.
foreach (ContactEdge ce in b.m_contactList)
{
Contact contact = ce.contact;
// Has this contact already been added to an island?
if (contact.m_flags.HasFlag(ContactFlags.e_islandFlag))
{
continue;
}
// Is this contact solid and touching?
if (contact.IsEnabled() == false ||
contact.IsTouching() == false)
{
continue;
}
// Skip sensors.
bool sensorA = contact.m_fixtureA.m_isSensor;
bool sensorB = contact.m_fixtureB.m_isSensor;
if (sensorA || sensorB)
{
continue;
}
island.Add(contact);
contact.m_flags |= ContactFlags.e_islandFlag;
Body other = ce.other;
// Was the other body already added to this island?
if (other.m_flags.HasFlag(Body.BodyFlags.e_islandFlag))
{
continue;
}
Utilities.Assert(stackCount < m_bodyList.Count());
stack.Add(other); stackCount++;
other.m_flags |= Body.BodyFlags.e_islandFlag;
}
// Search all joints connect to this body.
foreach (JointEdge je in b.m_jointList){
if (je.joint.m_islandFlag == true) {
continue;
}
Body other = je.other;
// Don't simulate joints connected to inactive bodies.
if (other.IsActive() == false) {
continue;
}
island.Add(je.joint);
je.joint.m_islandFlag = true;
if (other.m_flags.HasFlag(Body.BodyFlags.e_islandFlag)) {
continue;
}
stack.Add(other); stackCount++;
other.m_flags |= Body.BodyFlags.e_islandFlag;
}
}
Profile profile = new Profile();
island.Solve(profile, step, m_gravity, m_allowSleep);
m_profile.solveInit += profile.solveInit;
m_profile.solveVelocity += profile.solveVelocity;
m_profile.solvePosition += profile.solvePosition;
// Post solve cleanup.
for (int i = 0; i < island.m_bodies.Count(); ++i) {
// Allow static bodies to participate in other islands.
Body b = island.m_bodies[i];
if (b.GetBodyType() == BodyType._staticBody) {
b.m_flags &= ~Body.BodyFlags.e_islandFlag;
}
}
}
{
Timer timer = new Timer();
// Synchronize fixtures, check for out of range bodies.
foreach (Body b in m_bodyList)
{
// If a body was not in an island then it did not move.
if ((b.m_flags & Body.BodyFlags.e_islandFlag) == 0)
{
continue;
}
if (b.GetBodyType() == BodyType._staticBody)
{
continue;
}
// Update fixtures (for broad-phase).
b.SynchronizeFixtures();
}
// Look for new contacts.
m_contactManager.FindNewContacts();
m_profile.broadphase = timer.GetMilliseconds();
}
}
public void Solve(Profile profile, TimeStep step, Vec2 gravity, bool allowSleep) {
Timer timer = new Timer();
float h = step.dt;
// Integrate velocities and apply damping. Initialize the body state.
for (int i = 0; i < m_bodies.Count(); i++)
{
Body b = m_bodies[i];
Vec2 c = b.m_sweep.c;
float a = b.m_sweep.a;
Vec2 v = b.m_linearVelocity;
float w = b.m_angularVelocity;
// Store positions for continuous collision.
b.m_sweep.c0 = b.m_sweep.c;
b.m_sweep.a0 = b.m_sweep.a;
if (b.m_type == BodyType._dynamicBody)
{
// Integrate velocities.
v += h * (b.m_gravityScale * gravity + b.m_invMass * b.m_force);
w += h * b.m_invI * b.m_torque;
// Apply damping.
// ODE: dv/dt + c * v = 0
// Solution: v(t) = v0 * exp(-c * t)
// Time step: v(t + dt) = v0 * exp(-c * (t + dt)) = v0 * exp(-c * t) * exp(-c * dt) = v * exp(-c * dt)
// v2 = exp(-c * dt) * v1
// Taylor expansion:
// v2 = (1.0f - c * dt) * v1
v *= Utilities.Clamp(1.0f - h * b.m_linearDamping, 0.0f, 1.0f);
w *= Utilities.Clamp(1.0f - h * b.m_angularDamping, 0.0f, 1.0f);
}
Position pos = new Position();
pos.c = c;
pos.a = a;
m_positions.Add(pos);
Velocity vel = new Velocity();
vel.v = v;
vel.w = w;
m_velocities.Add(vel);
}
timer.Reset();
// Solver data
SolverData solverData;
solverData.step = step;
solverData.positions = m_positions;
solverData.velocities = m_velocities;
// Initialize velocity constraints.
ContactSolverDef contactSolverDef;
contactSolverDef.step = step;
contactSolverDef.contacts = m_contacts;
contactSolverDef.positions = m_positions;
contactSolverDef.velocities = m_velocities;
ContactSolver contactSolver = new ContactSolver(contactSolverDef);
contactSolver.InitializeVelocityConstraints();
if (step.warmStarting)
{
contactSolver.WarmStart();
}
for (int i = 0; i < m_joints.Count(); ++i)
{
m_joints[i].InitVelocityConstraints(solverData);
}
profile.solveInit = timer.GetMilliseconds();
// Solve velocity constraints
timer.Reset();
for (int i = 0; i < step.velocityIterations; ++i)
{
for (int j = 0; j < m_joints.Count(); ++j)
{
m_joints[j].SolveVelocityConstraints(solverData);
}
contactSolver.SolveVelocityConstraints();
}
// Store impulses for warm starting
contactSolver.StoreImpulses();
profile.solveVelocity = timer.GetMilliseconds();
// Integrate positions
for (int i = 0; i < m_bodies.Count(); ++i)
{
Vec2 c = m_positions[i].c;
float a = m_positions[i].a;
Vec2 v = m_velocities[i].v;
float w = m_velocities[i].w;
// Check for large velocities
Vec2 translation = h * v;
if (Utilities.Dot(translation, translation) > Settings._maxTranslationSquared)
{
float ratio = Settings._maxTranslation / translation.Length();
v *= ratio;
}
float rotation = h * w;
if (rotation * rotation > Settings._maxRotationSquared)
{
float ratio = Settings._maxRotation / Math.Abs(rotation);
w *= ratio;
}
// Integrate
c += h * v;
a += h * w;
m_positions[i].c = c;
m_positions[i].a = a;
m_velocities[i].v = v;
m_velocities[i].w = w;
}
// Solve position constraints
timer.Reset();
bool positionSolved = false;
for (int i = 0; i < step.positionIterations; ++i)
{
bool contactsOkay = contactSolver.SolvePositionConstraints();
bool jointsOkay = true;
for (int j = 0; j < m_joints.Count; ++j)
{
bool jointOkay = m_joints[j].SolvePositionConstraints(solverData);
jointsOkay = jointsOkay && jointOkay;
}
if (contactsOkay && jointsOkay)
{
// Exit early if the position errors are small.
positionSolved = true;
break;
}
}
// Copy state buffers back to the bodies
for (int i = 0; i < m_bodies.Count(); ++i)
{
Body body = m_bodies[i];
body.m_sweep.c = m_positions[i].c;
body.m_sweep.a = m_positions[i].a;
body.m_linearVelocity = m_velocities[i].v;
body.m_angularVelocity = m_velocities[i].w;
body.SynchronizeTransform();
}
profile.solvePosition = timer.GetMilliseconds();
Report(contactSolver.m_velocityConstraints);
if (allowSleep)
{
float minSleepTime = Single.MaxValue;
const float linTolSqr = Settings._linearSleepTolerance * Settings._linearSleepTolerance;
const float angTolSqr = Settings._angularSleepTolerance * Settings._angularSleepTolerance;
for (int i = 0; i < m_bodies.Count(); ++i)
{
Body b = m_bodies[i];
if (b.GetBodyType() == BodyType._staticBody)
{
continue;
}
if ((b.m_flags & Body.BodyFlags.e_autoSleepFlag) == 0 ||
b.m_angularVelocity * b.m_angularVelocity > angTolSqr ||
Utilities.Dot(b.m_linearVelocity, b.m_linearVelocity) > linTolSqr)
{
b.m_sleepTime = 0.0f;
minSleepTime = 0.0f;
}
else
{
b.m_sleepTime += h;
minSleepTime = Math.Min(minSleepTime, b.m_sleepTime);
}
}
if (minSleepTime >= Settings._timeToSleep && positionSolved)
{
for (int i = 0; i < m_bodies.Count(); ++i)
{
Body b = m_bodies[i];
b.SetAwake(false);
}
}
}
}