106 lines
3 KiB
C++
106 lines
3 KiB
C++
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#include "Bullet3Collision/NarrowPhaseCollision/shared/b3RigidBodyData.h"
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inline void integrateSingleTransform(__global b3RigidBodyData_t* bodies, int nodeID, float timeStep, float angularDamping, b3Float4ConstArg gravityAcceleration)
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{
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if (bodies[nodeID].m_invMass != 0.f)
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{
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float BT_GPU_ANGULAR_MOTION_THRESHOLD = (0.25f * 3.14159254f);
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//angular velocity
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{
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b3Float4 axis;
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//add some hardcoded angular damping
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bodies[nodeID].m_angVel.x *= angularDamping;
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bodies[nodeID].m_angVel.y *= angularDamping;
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bodies[nodeID].m_angVel.z *= angularDamping;
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b3Float4 angvel = bodies[nodeID].m_angVel;
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float fAngle = b3Sqrt(b3Dot3F4(angvel, angvel));
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//limit the angular motion
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if (fAngle * timeStep > BT_GPU_ANGULAR_MOTION_THRESHOLD)
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{
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fAngle = BT_GPU_ANGULAR_MOTION_THRESHOLD / timeStep;
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}
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if (fAngle < 0.001f)
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{
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// use Taylor's expansions of sync function
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axis = angvel * (0.5f * timeStep - (timeStep * timeStep * timeStep) * 0.020833333333f * fAngle * fAngle);
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}
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else
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{
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// sync(fAngle) = sin(c*fAngle)/t
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axis = angvel * (b3Sin(0.5f * fAngle * timeStep) / fAngle);
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}
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b3Quat dorn;
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dorn.x = axis.x;
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dorn.y = axis.y;
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dorn.z = axis.z;
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dorn.w = b3Cos(fAngle * timeStep * 0.5f);
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b3Quat orn0 = bodies[nodeID].m_quat;
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b3Quat predictedOrn = b3QuatMul(dorn, orn0);
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predictedOrn = b3QuatNormalized(predictedOrn);
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bodies[nodeID].m_quat = predictedOrn;
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}
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//linear velocity
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bodies[nodeID].m_pos += bodies[nodeID].m_linVel * timeStep;
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//apply gravity
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bodies[nodeID].m_linVel += gravityAcceleration * timeStep;
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}
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}
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inline void b3IntegrateTransform(__global b3RigidBodyData_t* body, float timeStep, float angularDamping, b3Float4ConstArg gravityAcceleration)
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{
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float BT_GPU_ANGULAR_MOTION_THRESHOLD = (0.25f * 3.14159254f);
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if ((body->m_invMass != 0.f))
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{
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//angular velocity
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{
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b3Float4 axis;
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//add some hardcoded angular damping
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body->m_angVel.x *= angularDamping;
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body->m_angVel.y *= angularDamping;
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body->m_angVel.z *= angularDamping;
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b3Float4 angvel = body->m_angVel;
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float fAngle = b3Sqrt(b3Dot3F4(angvel, angvel));
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//limit the angular motion
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if (fAngle * timeStep > BT_GPU_ANGULAR_MOTION_THRESHOLD)
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{
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fAngle = BT_GPU_ANGULAR_MOTION_THRESHOLD / timeStep;
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}
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if (fAngle < 0.001f)
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{
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// use Taylor's expansions of sync function
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axis = angvel * (0.5f * timeStep - (timeStep * timeStep * timeStep) * 0.020833333333f * fAngle * fAngle);
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}
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else
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{
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// sync(fAngle) = sin(c*fAngle)/t
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axis = angvel * (b3Sin(0.5f * fAngle * timeStep) / fAngle);
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}
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b3Quat dorn;
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dorn.x = axis.x;
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dorn.y = axis.y;
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dorn.z = axis.z;
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dorn.w = b3Cos(fAngle * timeStep * 0.5f);
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b3Quat orn0 = body->m_quat;
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b3Quat predictedOrn = b3QuatMul(dorn, orn0);
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predictedOrn = b3QuatNormalized(predictedOrn);
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body->m_quat = predictedOrn;
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}
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//apply gravity
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body->m_linVel += gravityAcceleration * timeStep;
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//linear velocity
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body->m_pos += body->m_linVel * timeStep;
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}
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}
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