Exemple #1
0
            public bool Callback(ref ManifoldPoint cp, CollisionObject colObj0, int partId0, int index0, CollisionObject colObj1, int partId1, int index1)
            {
                float friction0    = colObj0.GetFriction();
                float friction1    = colObj1.GetFriction();
                float restitution0 = colObj0.GetRestitution();
                float restitution1 = colObj1.GetRestitution();

                if ((colObj0.GetCollisionFlags() & CollisionFlags.CF_CUSTOM_MATERIAL_CALLBACK) != 0)
                {
                    friction0    = 1.0f;                 //partId0,index0
                    restitution0 = 0.0f;
                }
                if ((colObj1.GetCollisionFlags() & CollisionFlags.CF_CUSTOM_MATERIAL_CALLBACK) != 0)
                {
                    if ((index1 & 1) != 0)
                    {
                        friction1 = 1.0f;                        //partId1,index1
                    }
                    else
                    {
                        friction1 = 0f;
                    }
                    restitution1 = 0f;
                }

                cp.m_combinedFriction    = CalculateCombinedFriction(friction0, friction1);
                cp.m_combinedRestitution = calculateCombinedRestitution(restitution0, restitution1);

                //this return value is currently ignored, but to be on the safe side: return false if you don't calculate friction
                return(true);
            }
Exemple #2
0
        //response  between two dynamic objects without friction, assuming 0 penetration depth
        public static float ResolveSingleCollision(
            RigidBody body1,
            CollisionObject colObj2,
            ref IndexedVector3 contactPositionWorld,
            ref IndexedVector3 contactNormalOnB,
            ContactSolverInfo solverInfo,
            float distance)
        {
            RigidBody body2 = RigidBody.Upcast(colObj2);


            IndexedVector3 normal = contactNormalOnB;

            IndexedVector3 rel_pos1 = contactPositionWorld - body1.GetWorldTransform()._origin;
            IndexedVector3 rel_pos2 = contactPositionWorld - colObj2.GetWorldTransform()._origin;

            IndexedVector3 vel1 = body1.GetVelocityInLocalPoint(ref rel_pos1);
            IndexedVector3 vel2 = body2 != null?body2.GetVelocityInLocalPoint(ref rel_pos2) : IndexedVector3.Zero;

            IndexedVector3 vel     = vel1 - vel2;
            float          rel_vel = normal.Dot(ref vel);

            float combinedRestitution = body1.GetRestitution() * colObj2.GetRestitution();
            float restitution         = combinedRestitution * -rel_vel;

            float positionalError = solverInfo.m_erp * -distance / solverInfo.m_timeStep;
            float velocityError   = -(1.0f + restitution) * rel_vel;          // * damping;
            float denom0          = body1.ComputeImpulseDenominator(ref contactPositionWorld, ref normal);
            float denom1          = body2 != null?body2.ComputeImpulseDenominator(ref contactPositionWorld, ref normal) : 0.0f;

            float relaxation   = 1.0f;
            float jacDiagABInv = relaxation / (denom0 + denom1);

            float penetrationImpulse = positionalError * jacDiagABInv;
            float velocityImpulse    = velocityError * jacDiagABInv;

            float normalImpulse = penetrationImpulse + velocityImpulse;

            normalImpulse = 0.0f > normalImpulse ? 0.0f : normalImpulse;

            body1.ApplyImpulse(normal * (normalImpulse), rel_pos1);
            if (body2 != null)
            {
                body2.ApplyImpulse(-normal * (normalImpulse), rel_pos2);
            }

            return(normalImpulse);
        }
        public bool Callback(ref ManifoldPoint cp, CollisionObject colObj0, int partId0, int index0, CollisionObject colObj1, int partId1, int index1)
        {
            bool enable = true;

            if (enable)
            {
                InternalEdgeUtility.AdjustInternalEdgeContacts(cp, colObj1, colObj0, partId1, index1, BulletXNA.BulletCollision.CollisionDispatch.InternalEdgeUtility.InternalEdgeAdjustFlags.BT_TRIANGLE_CONVEX_BACKFACE_NONE);
                //btAdjustInternalEdgeContacts(cp,colObj1,colObj0, partId1,index1, BT_TRIANGLE_CONVEX_BACKFACE_MODE);
                //btAdjustInternalEdgeContacts(cp,colObj1,colObj0, partId1,index1, BT_TRIANGLE_CONVEX_DOUBLE_SIDED+BT_TRIANGLE_CONCAVE_DOUBLE_SIDED);
            }

            float friction0    = colObj0.GetFriction();
            float friction1    = colObj1.GetFriction();
            float restitution0 = colObj0.GetRestitution();
            float restitution1 = colObj1.GetRestitution();

            if ((colObj0.GetCollisionFlags() & CollisionFlags.CF_CUSTOM_MATERIAL_CALLBACK) != 0)
            {
                friction0    = 1.0f;     //partId0,index0
                restitution0 = 0.0f;
            }
            if ((colObj1.GetCollisionFlags() & CollisionFlags.CF_CUSTOM_MATERIAL_CALLBACK) != 0)
            {
                if ((index1 & 1) != 0)
                {
                    friction1 = 1.0f;            //partId1,index1
                }
                else
                {
                    friction1 = 0.0f;
                }
                restitution1 = 0.0f;
            }

            cp.m_combinedFriction    = CalculateCombinedFriction(friction0, friction1);
            cp.m_combinedRestitution = CalculateCombinedRestitution(restitution0, restitution1);

            //this return value is currently ignored, but to be on the safe side: return false if you don't calculate friction
            return(true);
        }