public void Initialize( int bodyCapacity, int contactCapacity, int jointCapacity, object allocator, b2ContactListener listener, b2ContactSolver contactSolver) { int i; m_bodyCapacity = bodyCapacity; m_contactCapacity = contactCapacity; m_jointCapacity = jointCapacity; m_bodyCount = 0; m_contactCount = 0; m_jointCount = 0; m_allocator = allocator; m_listener = listener; m_contactSolver = contactSolver; for (i = m_bodies.Count; i < bodyCapacity; i++) { m_bodies.Add(null); } for (i = m_contacts.Count; i < contactCapacity; i++) { m_contacts.Add(null); } for (i = m_joints.Count; i < jointCapacity; i++) { m_joints.Add(null); } }
public void SolveTOI(b2TimeStep subStep) { int i; int j; m_contactSolver.Initialize(subStep, m_contacts, m_contactCount, m_allocator); b2ContactSolver contactSolver = m_contactSolver; // No warm starting is needed for TOI events because warm // starting impulses were applied in the discrete solver. // Warm starting for joints is off for now, but we need to // call this function to compute Jacobians. for (i = 0; i < m_jointCount; ++i) { m_joints[i].InitVelocityConstraints(subStep); } // Solve velocity constraints. for (i = 0; i < subStep.velocityIterations; ++i) { contactSolver.SolveVelocityConstraints(); for (j = 0; j < m_jointCount; ++j) { m_joints[j].SolveVelocityConstraints(subStep); } } // Don't store the TOI contact forces for warm starting // because they can be quite large. // Integrate positions. for (i = 0; i < m_bodyCount; ++i) { b2Body b = m_bodies[i]; if (b.GetType() == b2Body.b2_staticBody) { continue; } // Check for large velocities. // b2Vec2 translation = subStep.dt * b.m_linearVelocity; float translationX = subStep.dt * b.m_linearVelocity.x; float translationY = subStep.dt * b.m_linearVelocity.y; //if (b2Dot(translation, translation) > b2_maxTranslationSquared) if ((translationX * translationX + translationY * translationY) > b2Settings.b2_maxTranslationSquared) { b.m_linearVelocity.Normalize(); b.m_linearVelocity.x *= b2Settings.b2_maxTranslation * subStep.inv_dt; b.m_linearVelocity.y *= b2Settings.b2_maxTranslation * subStep.inv_dt; } float rotation = subStep.dt * b.m_angularVelocity; if (rotation * rotation > b2Settings.b2_maxRotationSquared) { if (b.m_angularVelocity < 0.0f) { b.m_angularVelocity = -b2Settings.b2_maxRotation * subStep.inv_dt; } else { b.m_angularVelocity = b2Settings.b2_maxRotation * subStep.inv_dt; } } // Store positions for continuous collision. b.m_sweep.c0.SetV(b.m_sweep.c); b.m_sweep.a0 = b.m_sweep.a; // Integrate b.m_sweep.c.x += subStep.dt * b.m_linearVelocity.x; b.m_sweep.c.y += subStep.dt * b.m_linearVelocity.y; b.m_sweep.a += subStep.dt * b.m_angularVelocity; // Compute new transform b.SynchronizeTransform(); // Note: shapes are synchronized later. } // Solve position constraints. float k_toiBaumgarte = 0.75f; for (i = 0; i < subStep.positionIterations; ++i) { bool contactsOkay = contactSolver.SolvePositionConstraints(k_toiBaumgarte); bool jointsOkay = true; for (j = 0; j < m_jointCount; ++j) { bool jointOkay = m_joints[j].SolvePositionConstraints(b2Settings.b2_contactBaumgarte); jointsOkay = jointsOkay && jointOkay; } if (contactsOkay && jointsOkay) { break; } } Report(contactSolver.m_constraints); }
public void Solve(b2TimeStep step, b2Vec2 gravity, bool allowSleep) { int i; int j; b2Body b; b2Joint joint; // Integrate velocities and apply damping. for (i = 0; i < m_bodyCount; ++i) { b = m_bodies[i]; if (b.GetType() != b2Body.b2_dynamicBody) { continue; } //=====================add by kingBook 2015/10/26 17:25============== b2Vec2 l_gravity; if (b.m_customGravity != null) { l_gravity = b.m_customGravity; } else { l_gravity = gravity; } //==============================added================================ // Integrate velocities. //b.m_linearVelocity += step.dt * (gravity + b.m_invMass * b.m_force); b.m_linearVelocity.x += step.dt * (l_gravity.x + b.m_invMass * b.m_force.x); b.m_linearVelocity.y += step.dt * (l_gravity.y + b.m_invMass * b.m_force.y); b.m_angularVelocity += step.dt * 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 b.m_linearVelocity.Multiply(b2Math.Clamp(1.0f - step.dt * b.m_linearDamping, 0.0f, 1.0f)); b.m_angularVelocity *= b2Math.Clamp(1.0f - step.dt * b.m_angularDamping, 0.0f, 1.0f); } m_contactSolver.Initialize(step, m_contacts, m_contactCount, m_allocator); b2ContactSolver contactSolver = m_contactSolver; // Initialize velocity constraints. contactSolver.InitVelocityConstraints(step); for (i = 0; i < m_jointCount; ++i) { joint = m_joints[i]; joint.InitVelocityConstraints(step); } // Solve velocity constraints. for (i = 0; i < step.velocityIterations; ++i) { for (j = 0; j < m_jointCount; ++j) { joint = m_joints[j]; joint.SolveVelocityConstraints(step); } contactSolver.SolveVelocityConstraints(); } // Post-solve (store impulses for warm starting). for (i = 0; i < m_jointCount; ++i) { joint = m_joints[i]; joint.FinalizeVelocityConstraints(); } contactSolver.FinalizeVelocityConstraints(); // Integrate positions. for (i = 0; i < m_bodyCount; ++i) { b = m_bodies[i]; if (b.GetType() == b2Body.b2_staticBody) { continue; } // Check for large velocities. // b2Vec2 translation = step.dt * b.m_linearVelocity; float translationX = step.dt * b.m_linearVelocity.x; float translationY = step.dt * b.m_linearVelocity.y; //if (b2Dot(translation, translation) > b2_maxTranslationSquared) if ((translationX * translationX + translationY * translationY) > b2Settings.b2_maxTranslationSquared) { b.m_linearVelocity.Normalize(); b.m_linearVelocity.x *= b2Settings.b2_maxTranslation * step.inv_dt; b.m_linearVelocity.y *= b2Settings.b2_maxTranslation * step.inv_dt; } float rotation = step.dt * b.m_angularVelocity; if (rotation * rotation > b2Settings.b2_maxRotationSquared) { if (b.m_angularVelocity < 0.0f) { b.m_angularVelocity = -b2Settings.b2_maxRotation * step.inv_dt; } else { b.m_angularVelocity = b2Settings.b2_maxRotation * step.inv_dt; } } // Store positions for continuous collision. b.m_sweep.c0.SetV(b.m_sweep.c); b.m_sweep.a0 = b.m_sweep.a; // Integrate //b.m_sweep.c += step.dt * b.m_linearVelocity; //--------------修改start kingBook--------------- if (b.m_allowMovement) { b.m_sweep.c.x += step.dt * b.m_linearVelocity.x; b.m_sweep.c.y += step.dt * b.m_linearVelocity.y; } //--------------修改 end------------------------- b.m_sweep.a += step.dt * b.m_angularVelocity; // Compute new transform b.SynchronizeTransform(); // Note: shapes are synchronized later. } // Iterate over constraints. for (i = 0; i < step.positionIterations; ++i) { bool contactsOkay = contactSolver.SolvePositionConstraints(b2Settings.b2_contactBaumgarte); bool jointsOkay = true; for (j = 0; j < m_jointCount; ++j) { joint = m_joints[j]; bool jointOkay = joint.SolvePositionConstraints(b2Settings.b2_contactBaumgarte); jointsOkay = jointsOkay && jointOkay; } if (contactsOkay && jointsOkay) { break; } } Report(contactSolver.m_constraints); if (allowSleep) { float minSleepTime = float.MaxValue; float linTolSqr = b2Settings.b2_linearSleepTolerance * b2Settings.b2_linearSleepTolerance; float angTolSqr = b2Settings.b2_angularSleepTolerance * b2Settings.b2_angularSleepTolerance; for (i = 0; i < m_bodyCount; ++i) { b = m_bodies[i]; if (b.GetType() == b2Body.b2_staticBody) { continue; } if ((b.m_flags & b2Body.e_allowSleepFlag) == 0) { b.m_sleepTime = 0.0f; minSleepTime = 0.0f; } if ((b.m_flags & b2Body.e_allowSleepFlag) == 0 || b.m_angularVelocity * b.m_angularVelocity > angTolSqr || b2Math.Dot(b.m_linearVelocity, b.m_linearVelocity) > linTolSqr) { b.m_sleepTime = 0.0f; minSleepTime = 0.0f; } else { b.m_sleepTime += step.dt; minSleepTime = b2Math.Min(minSleepTime, b.m_sleepTime); } } if (minSleepTime >= b2Settings.b2_timeToSleep) { for (i = 0; i < m_bodyCount; ++i) { b = m_bodies[i]; b.SetAwake(false); } } } }
public void SolveTOI(b2TimeStep subStep, int toiIndexA, int toiIndexB) { Debug.Assert(toiIndexA < m_bodyCount); Debug.Assert(toiIndexB < m_bodyCount); // Initialize the body state. for (int i = 0; i < m_bodyCount; ++i) { b2Body b = m_bodies[i]; m_positions[i].c = b.Sweep.c; m_positions[i].a = b.Sweep.a; m_velocities[i].v = b.LinearVelocity; m_velocities[i].w = b.AngularVelocity; } b2ContactSolverDef contactSolverDef; contactSolverDef.contacts = m_contacts; contactSolverDef.count = m_contactCount; contactSolverDef.step = subStep; contactSolverDef.positions = m_positions; contactSolverDef.velocities = m_velocities; b2ContactSolver contactSolver = new b2ContactSolver(contactSolverDef); // Solve position constraints. for (int i = 0; i < subStep.positionIterations; ++i) { bool contactsOkay = contactSolver.SolveTOIPositionConstraints(toiIndexA, toiIndexB); if (contactsOkay) { break; } } #if false // Is the new position really safe? for (int i = 0; i < m_contactCount; ++i) { b2Contact c = m_contacts[i]; b2Fixture fA = c.GetFixtureA(); b2Fixture fB = c.GetFixtureB(); b2Body bA = fA.Body; b2Body bB = fB.Body; int indexA = c.GetChildIndexA(); int indexB = c.GetChildIndexB(); b2DistanceInput input = new b2DistanceInput(); input.proxyA.Set(fA.Shape, indexA); input.proxyB.Set(fB.Shape, indexB); input.transformA = bA.Transform; input.transformB = bB.Transform; input.useRadii = false; b2DistanceOutput output; b2SimplexCache cache = new b2SimplexCache(); cache.count = 0; output = b2Distance(cache, input); if (output.distance == 0 || cache.count == 3) { cache.count += 0; } } #endif // Leap of faith to new safe state. m_bodies[toiIndexA].Sweep.c0 = m_positions[toiIndexA].c; m_bodies[toiIndexA].Sweep.a0 = m_positions[toiIndexA].a; m_bodies[toiIndexB].Sweep.c0 = m_positions[toiIndexB].c; m_bodies[toiIndexB].Sweep.a0 = m_positions[toiIndexB].a; // No warm starting is needed for TOI events because warm // starting impulses were applied in the discrete solver. contactSolver.InitializeVelocityConstraints(); // Solve velocity constraints. for (int i = 0; i < subStep.velocityIterations; ++i) { contactSolver.SolveVelocityConstraints(); } // Don't store the TOI contact forces for warm starting // because they can be quite large. float h = subStep.dt; // Integrate positions for (int i = 0; i < m_bodyCount; ++i) { b2Vec2 c = m_positions[i].c; float a = m_positions[i].a; b2Vec2 v = m_velocities[i].v; float w = m_velocities[i].w; // Check for large velocities b2Vec2 translation = h * v; if (b2Math.b2Dot(translation, translation) > b2Settings.b2_maxTranslationSquared) { float ratio = b2Settings.b2_maxTranslation / translation.Length; v *= ratio; } float rotation = h * w; if (rotation * rotation > b2Settings.b2_maxRotationSquared) { float ratio = b2Settings.b2_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; // Sync bodies b2Body body = m_bodies[i]; body.Sweep.c = c; body.Sweep.a = a; body.LinearVelocity = v; body.AngularVelocity = w; body.SynchronizeTransform(); } Report(contactSolver.m_velocityConstraints); }
public void Solve(b2TimeStep step, b2Vec2 gravity, bool allowSleep) #endif { #if PROFILING b2Timer timer = new b2Timer(); #endif float h = step.dt; // Integrate velocities and apply damping. Initialize the body state. for (int i = 0; i < m_bodyCount; ++i) { b2Body b = m_bodies[i]; b2Vec2 c = b.Sweep.c; float a = b.Sweep.a; b2Vec2 v = b.LinearVelocity; float w = b.AngularVelocity; // Store positions for continuous collision. b.Sweep.c0 = b.Sweep.c; b.Sweep.a0 = b.Sweep.a; if (b.BodyType == b2BodyType.b2_dynamicBody) { // Integrate velocities. v += h * (b.GravityScale * gravity + b.InvertedMass * b.Force); w += h * b.InvertedI * b.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 *= b2Math.b2Clamp(1.0f - h * b.LinearDamping, 0.0f, 1.0f); w *= b2Math.b2Clamp(1.0f - h * b.AngularDamping, 0.0f, 1.0f); } m_positions[i].c = c; m_positions[i].a = a; m_velocities[i].v = v; m_velocities[i].w = w; } #if PROFILING timer.Reset(); #endif // Solver data b2SolverData solverData = new b2SolverData(); solverData.step = step; solverData.positions = m_positions; solverData.velocities = m_velocities; // Initialize velocity constraints. b2ContactSolverDef contactSolverDef; contactSolverDef.step = step; contactSolverDef.contacts = m_contacts; contactSolverDef.count = m_contactCount; contactSolverDef.positions = m_positions; contactSolverDef.velocities = m_velocities; b2ContactSolver contactSolver = new b2ContactSolver(contactSolverDef); contactSolver.InitializeVelocityConstraints(); if (step.warmStarting) { contactSolver.WarmStart(); } for (int i = 0; i < m_jointCount; ++i) { m_joints[i].InitVelocityConstraints(solverData); } #if PROFILING profile.solveInit = timer.GetMilliseconds(); #endif // Solve velocity constraints #if PROFILING timer.Reset(); #endif for (int i = 0; i < step.velocityIterations; ++i) { for (int j = 0; j < m_jointCount; ++j) { m_joints[j].SolveVelocityConstraints(solverData); } contactSolver.SolveVelocityConstraints(); } // Store impulses for warm starting contactSolver.StoreImpulses(); #if PROFILING profile.solveVelocity = timer.GetMilliseconds(); #endif // Integrate positions for (int i = 0; i < m_bodyCount; ++i) { b2Vec2 c = m_positions[i].c; float a = m_positions[i].a; b2Vec2 v = m_velocities[i].v; float w = m_velocities[i].w; // Check for large velocities b2Vec2 translation = h * v; if (translation.LengthSquared /* b2Math.b2Dot(translation, translation)*/ > b2Settings.b2_maxTranslationSquared) { float ratio = b2Settings.b2_maxTranslation / translation.Length; v *= ratio; } float rotation = h * w; if (rotation * rotation > b2Settings.b2_maxRotationSquared) { float ratio = b2Settings.b2_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 #if PROFILING timer.Reset(); #endif bool positionSolved = false; for (int i = 0; i < step.positionIterations; ++i) { bool contactsOkay = contactSolver.SolvePositionConstraints(); bool jointsOkay = true; for (int i2 = 0; i2 < m_jointCount; ++i2) { bool jointOkay = m_joints[i2].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_bodyCount; ++i) { b2Body body = m_bodies[i]; body.Sweep.c = m_positions[i].c; body.Sweep.a = m_positions[i].a; body.LinearVelocity = m_velocities[i].v; body.AngularVelocity = m_velocities[i].w; body.SynchronizeTransform(); } #if PROFILING profile.solvePosition = timer.GetMilliseconds(); #endif Report(contactSolver.m_velocityConstraints); if (allowSleep) { float minSleepTime = b2Settings.b2_maxFloat; float linTolSqr = b2Settings.b2_linearSleepTolerance * b2Settings.b2_linearSleepTolerance; float angTolSqr = b2Settings.b2_angularSleepTolerance * b2Settings.b2_angularSleepTolerance; for (int i = 0; i < m_bodyCount; ++i) { b2Body b = m_bodies[i]; if (b.BodyType == b2BodyType.b2_staticBody) { continue; } if (!(b.BodyFlags.HasFlag(b2BodyFlags.e_autoSleepFlag)) || b.AngularVelocity * b.AngularVelocity > angTolSqr || b2Math.b2Dot(b.LinearVelocity, b.LinearVelocity) > linTolSqr) { b.SleepTime = 0.0f; minSleepTime = 0.0f; } else { b.SleepTime += h; minSleepTime = Math.Min(minSleepTime, b.SleepTime); } } if (minSleepTime >= b2Settings.b2_timeToSleep && positionSolved) { for (int i = 0; i < m_bodyCount; ++i) { b2Body b = m_bodies[i]; b.SetAwake(false); } } } }
public void Solve(b2Profile profile, b2TimeStep step, b2Vec2 gravity, bool allowSleep) { b2Timer timer = new b2Timer(); float h = step.dt; // Integrate velocities and apply damping. Initialize the body state. for (int i = 0; i < m_bodyCount; ++i) { b2Body b = m_bodies[i]; b2Vec2 c = new b2Vec2(b.m_sweep.c); float a = b.m_sweep.a; b2Vec2 v = new b2Vec2(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.b2_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 // Pade approximation: // v2 = v1 * 1 / (1 + c * dt) v *= 1.0f / (1.0f + h * b.m_linearDamping); w *= 1.0f / (1.0f + h * b.m_angularDamping); } m_positions[i].c = c; m_positions[i].a = a; m_velocities[i].v = v; m_velocities[i].w = w; } timer.Reset(); // Solver data b2SolverData solverData = new b2SolverData(); solverData.step = step; solverData.positions = m_positions; solverData.velocities = m_velocities; // Initialize velocity constraints. b2ContactSolverDef contactSolverDef = new b2ContactSolverDef(); contactSolverDef.step = step; contactSolverDef.contacts = m_contacts; contactSolverDef.count = m_contactCount; contactSolverDef.positions = m_positions; contactSolverDef.velocities = m_velocities; b2ContactSolver contactSolver = new b2ContactSolver(contactSolverDef); contactSolver.InitializeVelocityConstraints(); if (step.warmStarting) { contactSolver.WarmStart(); } for (int i = 0; i < m_jointCount; ++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_jointCount; ++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_bodyCount; ++i) { b2Vec2 c = m_positions[i].c; float a = m_positions[i].a; b2Vec2 v = m_velocities[i].v; float w = m_velocities[i].w; // Check for large velocities b2Vec2 translation = h * v; if (Utils.b2Dot(translation, translation) > (Settings.b2_maxTranslation * Settings.b2_maxTranslation)) { float ratio = Settings.b2_maxTranslation / translation.Length(); v *= ratio; } float rotation = h * w; if (rotation * rotation > Settings.b2_maxRotationSquared) { float ratio = (0.5f * Settings.b2_pi) / Utils.b2Abs(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_jointCount; ++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_bodyCount; ++i) { b2Body 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 = float.MaxValue; const float linTolSqr = Settings.b2_linearSleepTolerance * Settings.b2_linearSleepTolerance; float angTolSqr = Settings.b2_angularSlop * Settings.b2_angularSlop; for (int i = 0; i < m_bodyCount; ++i) { b2Body b = m_bodies[i]; if (b.GetType() == BodyType.b2_staticBody) { continue; } if ((b.m_flags & b2Body.BodyFlags.e_autoSleepFlag) == 0 || b.m_angularVelocity * b.m_angularVelocity > angTolSqr || Utils.b2Dot(b.m_linearVelocity, b.m_linearVelocity) > linTolSqr) { b.m_sleepTime = 0.0f; minSleepTime = 0.0f; } else { b.m_sleepTime += h; minSleepTime = Utils.b2Min(minSleepTime, b.m_sleepTime); } } if (minSleepTime >= Settings.b2_timeToSleep && positionSolved) { for (int i = 0; i < m_bodyCount; ++i) { b2Body b = m_bodies[i]; b.SetAwake(false); } } } }