/*************************************************************************/ /* slider_joint_sw.cpp */ /*************************************************************************/ /* This file is part of: */ /* GODOT ENGINE */ /* http://www.godotengine.org */ /*************************************************************************/ /* Copyright (c) 2007-2017 Juan Linietsky, Ariel Manzur. */ /* Copyright (c) 2014-2017 Godot Engine contributors (cf. AUTHORS.md) */ /* */ /* 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. */ /*************************************************************************/ /* Adapted to Godot from the Bullet library. See corresponding header file for licensing info. */ #include "slider_joint_sw.h" //----------------------------------------------------------------------------- static _FORCE_INLINE_ real_t atan2fast(real_t y, real_t x) { real_t coeff_1 = Math_PI / 4.0f; real_t coeff_2 = 3.0f * coeff_1; real_t abs_y = Math::abs(y); real_t angle; if (x >= 0.0f) { real_t r = (x - abs_y) / (x + abs_y); angle = coeff_1 - coeff_1 * r; } else { real_t r = (x + abs_y) / (abs_y - x); angle = coeff_2 - coeff_1 * r; } return (y < 0.0f) ? -angle : angle; } void SliderJointSW::initParams() { m_lowerLinLimit = real_t(1.0); m_upperLinLimit = real_t(-1.0); m_lowerAngLimit = real_t(0.); m_upperAngLimit = real_t(0.); m_softnessDirLin = SLIDER_CONSTRAINT_DEF_SOFTNESS; m_restitutionDirLin = SLIDER_CONSTRAINT_DEF_RESTITUTION; m_dampingDirLin = real_t(0.); m_softnessDirAng = SLIDER_CONSTRAINT_DEF_SOFTNESS; m_restitutionDirAng = SLIDER_CONSTRAINT_DEF_RESTITUTION; m_dampingDirAng = real_t(0.); m_softnessOrthoLin = SLIDER_CONSTRAINT_DEF_SOFTNESS; m_restitutionOrthoLin = SLIDER_CONSTRAINT_DEF_RESTITUTION; m_dampingOrthoLin = SLIDER_CONSTRAINT_DEF_DAMPING; m_softnessOrthoAng = SLIDER_CONSTRAINT_DEF_SOFTNESS; m_restitutionOrthoAng = SLIDER_CONSTRAINT_DEF_RESTITUTION; m_dampingOrthoAng = SLIDER_CONSTRAINT_DEF_DAMPING; m_softnessLimLin = SLIDER_CONSTRAINT_DEF_SOFTNESS; m_restitutionLimLin = SLIDER_CONSTRAINT_DEF_RESTITUTION; m_dampingLimLin = SLIDER_CONSTRAINT_DEF_DAMPING; m_softnessLimAng = SLIDER_CONSTRAINT_DEF_SOFTNESS; m_restitutionLimAng = SLIDER_CONSTRAINT_DEF_RESTITUTION; m_dampingLimAng = SLIDER_CONSTRAINT_DEF_DAMPING; m_poweredLinMotor = false; m_targetLinMotorVelocity = real_t(0.); m_maxLinMotorForce = real_t(0.); m_accumulatedLinMotorImpulse = real_t(0.0); m_poweredAngMotor = false; m_targetAngMotorVelocity = real_t(0.); m_maxAngMotorForce = real_t(0.); m_accumulatedAngMotorImpulse = real_t(0.0); } // SliderJointSW::initParams() //----------------------------------------------------------------------------- //----------------------------------------------------------------------------- SliderJointSW::SliderJointSW(BodySW *rbA, BodySW *rbB, const Transform &frameInA, const Transform &frameInB) : JointSW(_arr, 2), m_frameInA(frameInA), m_frameInB(frameInB) { A = rbA; B = rbB; A->add_constraint(this, 0); B->add_constraint(this, 1); initParams(); } // SliderJointSW::SliderJointSW() //----------------------------------------------------------------------------- bool SliderJointSW::setup(real_t p_step) { //calculate transforms m_calculatedTransformA = A->get_transform() * m_frameInA; m_calculatedTransformB = B->get_transform() * m_frameInB; m_realPivotAInW = m_calculatedTransformA.origin; m_realPivotBInW = m_calculatedTransformB.origin; m_sliderAxis = m_calculatedTransformA.basis.get_axis(0); // along X m_delta = m_realPivotBInW - m_realPivotAInW; m_projPivotInW = m_realPivotAInW + m_sliderAxis.dot(m_delta) * m_sliderAxis; m_relPosA = m_projPivotInW - A->get_transform().origin; m_relPosB = m_realPivotBInW - B->get_transform().origin; Vector3 normalWorld; int i; //linear part for (i = 0; i < 3; i++) { normalWorld = m_calculatedTransformA.basis.get_axis(i); memnew_placement(&m_jacLin[i], JacobianEntrySW( A->get_principal_inertia_axes().transposed(), B->get_principal_inertia_axes().transposed(), m_relPosA - A->get_center_of_mass(), m_relPosB - B->get_center_of_mass(), normalWorld, A->get_inv_inertia(), A->get_inv_mass(), B->get_inv_inertia(), B->get_inv_mass())); m_jacLinDiagABInv[i] = real_t(1.) / m_jacLin[i].getDiagonal(); m_depth[i] = m_delta.dot(normalWorld); } testLinLimits(); // angular part for (i = 0; i < 3; i++) { normalWorld = m_calculatedTransformA.basis.get_axis(i); memnew_placement(&m_jacAng[i], JacobianEntrySW( normalWorld, A->get_principal_inertia_axes().transposed(), B->get_principal_inertia_axes().transposed(), A->get_inv_inertia(), B->get_inv_inertia())); } testAngLimits(); Vector3 axisA = m_calculatedTransformA.basis.get_axis(0); m_kAngle = real_t(1.0) / (A->compute_angular_impulse_denominator(axisA) + B->compute_angular_impulse_denominator(axisA)); // clear accumulator for motors m_accumulatedLinMotorImpulse = real_t(0.0); m_accumulatedAngMotorImpulse = real_t(0.0); return true; } // SliderJointSW::buildJacobianInt() //----------------------------------------------------------------------------- void SliderJointSW::solve(real_t p_step) { int i; // linear Vector3 velA = A->get_velocity_in_local_point(m_relPosA); Vector3 velB = B->get_velocity_in_local_point(m_relPosB); Vector3 vel = velA - velB; for (i = 0; i < 3; i++) { const Vector3 &normal = m_jacLin[i].m_linearJointAxis; real_t rel_vel = normal.dot(vel); // calculate positional error real_t depth = m_depth[i]; // get parameters real_t softness = (i) ? m_softnessOrthoLin : (m_solveLinLim ? m_softnessLimLin : m_softnessDirLin); real_t restitution = (i) ? m_restitutionOrthoLin : (m_solveLinLim ? m_restitutionLimLin : m_restitutionDirLin); real_t damping = (i) ? m_dampingOrthoLin : (m_solveLinLim ? m_dampingLimLin : m_dampingDirLin); // calcutate and apply impulse real_t normalImpulse = softness * (restitution * depth / p_step - damping * rel_vel) * m_jacLinDiagABInv[i]; Vector3 impulse_vector = normal * normalImpulse; A->apply_impulse(m_relPosA, impulse_vector); B->apply_impulse(m_relPosB, -impulse_vector); if (m_poweredLinMotor && (!i)) { // apply linear motor if (m_accumulatedLinMotorImpulse < m_maxLinMotorForce) { real_t desiredMotorVel = m_targetLinMotorVelocity; real_t motor_relvel = desiredMotorVel + rel_vel; normalImpulse = -motor_relvel * m_jacLinDiagABInv[i]; // clamp accumulated impulse real_t new_acc = m_accumulatedLinMotorImpulse + Math::abs(normalImpulse); if (new_acc > m_maxLinMotorForce) { new_acc = m_maxLinMotorForce; } real_t del = new_acc - m_accumulatedLinMotorImpulse; if (normalImpulse < real_t(0.0)) { normalImpulse = -del; } else { normalImpulse = del; } m_accumulatedLinMotorImpulse = new_acc; // apply clamped impulse impulse_vector = normal * normalImpulse; A->apply_impulse(m_relPosA, impulse_vector); B->apply_impulse(m_relPosB, -impulse_vector); } } } // angular // get axes in world space Vector3 axisA = m_calculatedTransformA.basis.get_axis(0); Vector3 axisB = m_calculatedTransformB.basis.get_axis(0); const Vector3 &angVelA = A->get_angular_velocity(); const Vector3 &angVelB = B->get_angular_velocity(); Vector3 angVelAroundAxisA = axisA * axisA.dot(angVelA); Vector3 angVelAroundAxisB = axisB * axisB.dot(angVelB); Vector3 angAorthog = angVelA - angVelAroundAxisA; Vector3 angBorthog = angVelB - angVelAroundAxisB; Vector3 velrelOrthog = angAorthog - angBorthog; //solve orthogonal angular velocity correction real_t len = velrelOrthog.length(); if (len > real_t(0.00001)) { Vector3 normal = velrelOrthog.normalized(); real_t denom = A->compute_angular_impulse_denominator(normal) + B->compute_angular_impulse_denominator(normal); velrelOrthog *= (real_t(1.) / denom) * m_dampingOrthoAng * m_softnessOrthoAng; } //solve angular positional correction Vector3 angularError = axisA.cross(axisB) * (real_t(1.) / p_step); real_t len2 = angularError.length(); if (len2 > real_t(0.00001)) { Vector3 normal2 = angularError.normalized(); real_t denom2 = A->compute_angular_impulse_denominator(normal2) + B->compute_angular_impulse_denominator(normal2); angularError *= (real_t(1.) / denom2) * m_restitutionOrthoAng * m_softnessOrthoAng; } // apply impulse A->apply_torque_impulse(-velrelOrthog + angularError); B->apply_torque_impulse(velrelOrthog - angularError); real_t impulseMag; //solve angular limits if (m_solveAngLim) { impulseMag = (angVelB - angVelA).dot(axisA) * m_dampingLimAng + m_angDepth * m_restitutionLimAng / p_step; impulseMag *= m_kAngle * m_softnessLimAng; } else { impulseMag = (angVelB - angVelA).dot(axisA) * m_dampingDirAng + m_angDepth * m_restitutionDirAng / p_step; impulseMag *= m_kAngle * m_softnessDirAng; } Vector3 impulse = axisA * impulseMag; A->apply_torque_impulse(impulse); B->apply_torque_impulse(-impulse); //apply angular motor if (m_poweredAngMotor) { if (m_accumulatedAngMotorImpulse < m_maxAngMotorForce) { Vector3 velrel = angVelAroundAxisA - angVelAroundAxisB; real_t projRelVel = velrel.dot(axisA); real_t desiredMotorVel = m_targetAngMotorVelocity; real_t motor_relvel = desiredMotorVel - projRelVel; real_t angImpulse = m_kAngle * motor_relvel; // clamp accumulated impulse real_t new_acc = m_accumulatedAngMotorImpulse + Math::abs(angImpulse); if (new_acc > m_maxAngMotorForce) { new_acc = m_maxAngMotorForce; } real_t del = new_acc - m_accumulatedAngMotorImpulse; if (angImpulse < real_t(0.0)) { angImpulse = -del; } else { angImpulse = del; } m_accumulatedAngMotorImpulse = new_acc; // apply clamped impulse Vector3 motorImp = angImpulse * axisA; A->apply_torque_impulse(motorImp); B->apply_torque_impulse(-motorImp); } } } // SliderJointSW::solveConstraint() //----------------------------------------------------------------------------- //----------------------------------------------------------------------------- void SliderJointSW::calculateTransforms(void) { m_calculatedTransformA = A->get_transform() * m_frameInA; m_calculatedTransformB = B->get_transform() * m_frameInB; m_realPivotAInW = m_calculatedTransformA.origin; m_realPivotBInW = m_calculatedTransformB.origin; m_sliderAxis = m_calculatedTransformA.basis.get_axis(0); // along X m_delta = m_realPivotBInW - m_realPivotAInW; m_projPivotInW = m_realPivotAInW + m_sliderAxis.dot(m_delta) * m_sliderAxis; Vector3 normalWorld; int i; //linear part for (i = 0; i < 3; i++) { normalWorld = m_calculatedTransformA.basis.get_axis(i); m_depth[i] = m_delta.dot(normalWorld); } } // SliderJointSW::calculateTransforms() //----------------------------------------------------------------------------- void SliderJointSW::testLinLimits(void) { m_solveLinLim = false; m_linPos = m_depth[0]; if (m_lowerLinLimit <= m_upperLinLimit) { if (m_depth[0] > m_upperLinLimit) { m_depth[0] -= m_upperLinLimit; m_solveLinLim = true; } else if (m_depth[0] < m_lowerLinLimit) { m_depth[0] -= m_lowerLinLimit; m_solveLinLim = true; } else { m_depth[0] = real_t(0.); } } else { m_depth[0] = real_t(0.); } } // SliderJointSW::testLinLimits() //----------------------------------------------------------------------------- void SliderJointSW::testAngLimits(void) { m_angDepth = real_t(0.); m_solveAngLim = false; if (m_lowerAngLimit <= m_upperAngLimit) { const Vector3 axisA0 = m_calculatedTransformA.basis.get_axis(1); const Vector3 axisA1 = m_calculatedTransformA.basis.get_axis(2); const Vector3 axisB0 = m_calculatedTransformB.basis.get_axis(1); real_t rot = atan2fast(axisB0.dot(axisA1), axisB0.dot(axisA0)); if (rot < m_lowerAngLimit) { m_angDepth = rot - m_lowerAngLimit; m_solveAngLim = true; } else if (rot > m_upperAngLimit) { m_angDepth = rot - m_upperAngLimit; m_solveAngLim = true; } } } // SliderJointSW::testAngLimits() //----------------------------------------------------------------------------- Vector3 SliderJointSW::getAncorInA(void) { Vector3 ancorInA; ancorInA = m_realPivotAInW + (m_lowerLinLimit + m_upperLinLimit) * real_t(0.5) * m_sliderAxis; ancorInA = A->get_transform().inverse().xform(ancorInA); return ancorInA; } // SliderJointSW::getAncorInA() //----------------------------------------------------------------------------- Vector3 SliderJointSW::getAncorInB(void) { Vector3 ancorInB; ancorInB = m_frameInB.origin; return ancorInB; } // SliderJointSW::getAncorInB(); void SliderJointSW::set_param(PhysicsServer::SliderJointParam p_param, real_t p_value) { switch (p_param) { case PhysicsServer::SLIDER_JOINT_LINEAR_LIMIT_UPPER: m_upperLinLimit = p_value; break; case PhysicsServer::SLIDER_JOINT_LINEAR_LIMIT_LOWER: m_lowerLinLimit = p_value; break; case PhysicsServer::SLIDER_JOINT_LINEAR_LIMIT_SOFTNESS: m_softnessLimLin = p_value; break; case PhysicsServer::SLIDER_JOINT_LINEAR_LIMIT_RESTITUTION: m_restitutionLimLin = p_value; break; case PhysicsServer::SLIDER_JOINT_LINEAR_LIMIT_DAMPING: m_dampingLimLin = p_value; break; case PhysicsServer::SLIDER_JOINT_LINEAR_MOTION_SOFTNESS: m_softnessDirLin = p_value; break; case PhysicsServer::SLIDER_JOINT_LINEAR_MOTION_RESTITUTION: m_restitutionDirLin = p_value; break; case PhysicsServer::SLIDER_JOINT_LINEAR_MOTION_DAMPING: m_dampingDirLin = p_value; break; case PhysicsServer::SLIDER_JOINT_LINEAR_ORTHOGONAL_SOFTNESS: m_softnessOrthoLin = p_value; break; case PhysicsServer::SLIDER_JOINT_LINEAR_ORTHOGONAL_RESTITUTION: m_restitutionOrthoLin = p_value; break; case PhysicsServer::SLIDER_JOINT_LINEAR_ORTHOGONAL_DAMPING: m_dampingOrthoLin = p_value; break; case PhysicsServer::SLIDER_JOINT_ANGULAR_LIMIT_UPPER: m_upperAngLimit = p_value; break; case PhysicsServer::SLIDER_JOINT_ANGULAR_LIMIT_LOWER: m_lowerAngLimit = p_value; break; case PhysicsServer::SLIDER_JOINT_ANGULAR_LIMIT_SOFTNESS: m_softnessLimAng = p_value; break; case PhysicsServer::SLIDER_JOINT_ANGULAR_LIMIT_RESTITUTION: m_restitutionLimAng = p_value; break; case PhysicsServer::SLIDER_JOINT_ANGULAR_LIMIT_DAMPING: m_dampingLimAng = p_value; break; case PhysicsServer::SLIDER_JOINT_ANGULAR_MOTION_SOFTNESS: m_softnessDirAng = p_value; break; case PhysicsServer::SLIDER_JOINT_ANGULAR_MOTION_RESTITUTION: m_restitutionDirAng = p_value; break; case PhysicsServer::SLIDER_JOINT_ANGULAR_MOTION_DAMPING: m_dampingDirAng = p_value; break; case PhysicsServer::SLIDER_JOINT_ANGULAR_ORTHOGONAL_SOFTNESS: m_softnessOrthoAng = p_value; break; case PhysicsServer::SLIDER_JOINT_ANGULAR_ORTHOGONAL_RESTITUTION: m_restitutionOrthoAng = p_value; break; case PhysicsServer::SLIDER_JOINT_ANGULAR_ORTHOGONAL_DAMPING: m_dampingOrthoAng = p_value; break; } } real_t SliderJointSW::get_param(PhysicsServer::SliderJointParam p_param) const { switch (p_param) { case PhysicsServer::SLIDER_JOINT_LINEAR_LIMIT_UPPER: return m_upperLinLimit; case PhysicsServer::SLIDER_JOINT_LINEAR_LIMIT_LOWER: return m_lowerLinLimit; case PhysicsServer::SLIDER_JOINT_LINEAR_LIMIT_SOFTNESS: return m_softnessLimLin; case PhysicsServer::SLIDER_JOINT_LINEAR_LIMIT_RESTITUTION: return m_restitutionLimLin; case PhysicsServer::SLIDER_JOINT_LINEAR_LIMIT_DAMPING: return m_dampingLimLin; case PhysicsServer::SLIDER_JOINT_LINEAR_MOTION_SOFTNESS: return m_softnessDirLin; case PhysicsServer::SLIDER_JOINT_LINEAR_MOTION_RESTITUTION: return m_restitutionDirLin; case PhysicsServer::SLIDER_JOINT_LINEAR_MOTION_DAMPING: return m_dampingDirLin; case PhysicsServer::SLIDER_JOINT_LINEAR_ORTHOGONAL_SOFTNESS: return m_softnessOrthoLin; case PhysicsServer::SLIDER_JOINT_LINEAR_ORTHOGONAL_RESTITUTION: return m_restitutionOrthoLin; case PhysicsServer::SLIDER_JOINT_LINEAR_ORTHOGONAL_DAMPING: return m_dampingOrthoLin; case PhysicsServer::SLIDER_JOINT_ANGULAR_LIMIT_UPPER: return m_upperAngLimit; case PhysicsServer::SLIDER_JOINT_ANGULAR_LIMIT_LOWER: return m_lowerAngLimit; case PhysicsServer::SLIDER_JOINT_ANGULAR_LIMIT_SOFTNESS: return m_softnessLimAng; case PhysicsServer::SLIDER_JOINT_ANGULAR_LIMIT_RESTITUTION: return m_restitutionLimAng; case PhysicsServer::SLIDER_JOINT_ANGULAR_LIMIT_DAMPING: return m_dampingLimAng; case PhysicsServer::SLIDER_JOINT_ANGULAR_MOTION_SOFTNESS: return m_softnessDirAng; case PhysicsServer::SLIDER_JOINT_ANGULAR_MOTION_RESTITUTION: return m_restitutionDirAng; case PhysicsServer::SLIDER_JOINT_ANGULAR_MOTION_DAMPING: return m_dampingDirAng; case PhysicsServer::SLIDER_JOINT_ANGULAR_ORTHOGONAL_SOFTNESS: return m_softnessOrthoAng; case PhysicsServer::SLIDER_JOINT_ANGULAR_ORTHOGONAL_RESTITUTION: return m_restitutionOrthoAng; case PhysicsServer::SLIDER_JOINT_ANGULAR_ORTHOGONAL_DAMPING: return m_dampingOrthoAng; } return 0; }