Exemplo n.º 1
0
        /// <summary>
        /// GetBoxTriangleIntersectionPoints
        /// Pushes intersection points onto the back of pts. Returns the
        /// number of points found.
        /// Points that are close together (compared to 
        /// combinationDistance) get combined
        /// </summary>
        /// <param name="pts"></param>
        /// <param name="box"></param>
        /// <param name="triangle"></param>
        /// <param name="combinationDistance"></param>
        /// <returns>int</returns>
        private static int GetBoxTriangleIntersectionPoints(List<Vector3> pts, Box box, Triangle triangle, float combinationDistance)
        {
            // first intersect each edge of the box with the triangle
            Box.Edge[] edges;
            box.GetEdges(out edges);
            Vector3[] boxPts;
            box.GetCornerPoints(out boxPts);

            float tS;
            float tv1, tv2;

            // BEN-OPTIMISATION: Allocating just one Vector3 to be reused.
            Vector3 point = new Vector3();

            int iEdge;
            for (iEdge = 0; iEdge < 12; ++iEdge)
            {
                Box.Edge edge = edges[iEdge];
                Segment seg = new Segment(boxPts[(int)edge.Ind0], boxPts[(int)edge.Ind1] - boxPts[(int)edge.Ind0]);
                if (Intersection.SegmentTriangleIntersection(out tS, out tv1, out tv2, seg, triangle))
                {
                    // BEN-OPTIMISATION: Reusing the existing point variable instead allocating new ones.
                    //                   This also allows point to be based by reference.
                    seg.GetPoint(ref point, tS);
                    AddPoint(pts, ref point, combinationDistance * combinationDistance);
                }
            }

            Vector3 pos, n;
            // now each edge of the triangle with the box
            for (iEdge = 0; iEdge < 3; ++iEdge)
            {
                #region "BEN-OPTIMISATION: Remove excess allocations and pass variables by reference."
                // ORIGINAL CODE:
                /*Vector3 pt0 = triangle.GetPoint(iEdge);
                Vector3 pt1 = triangle.GetPoint((iEdge + 1) % 3);
                Segment s1 = new Segment(pt0, pt1 - pt0);
                Segment s2 = new Segment(pt1, pt0 - pt1);*/

                // OPTIMISED CODE:
                Vector3 pt0 = triangle.GetPoint(iEdge);
                Vector3 pt1 = triangle.GetPoint((iEdge + 1) % 3);

                Vector3 difference1;
                Vector3 difference2;

                Vector3.Subtract(ref pt1, ref pt0, out difference1);
                Vector3.Subtract(ref pt0, ref pt1, out difference2);

                Segment s1 = new Segment(ref pt0, ref difference1);
                Segment s2 = new Segment(ref pt1, ref difference2);
                #endregion

                if (box.SegmentIntersect(out tS, out pos, out n, s1))
                    AddPoint(pts, ref pos, combinationDistance * combinationDistance);
                if (box.SegmentIntersect(out tS, out pos, out n, s2))
                    AddPoint(pts, ref pos, combinationDistance * combinationDistance);
            }

            return pts.Count;
        }
Exemplo n.º 2
0
        public static void CollDetectSphereStaticMeshOverlap(BoundingSphere oldSphere, BoundingSphere newSphere,
            TriangleMesh mesh, CollDetectInfo info, float collTolerance, CollisionFunctor collisionFunctor)
        {
            Vector3 body0Pos = (info.Skin0.Owner != null) ? info.Skin0.Owner.OldPosition : Vector3.Zero;
            Vector3 body1Pos = (info.Skin1.Owner != null) ? info.Skin1.Owner.OldPosition : Vector3.Zero;

            float sphereTolR = collTolerance + newSphere.Radius;
            float sphereTolR2 = sphereTolR * sphereTolR;

            unsafe
            {
            #if USE_STACKALLOC
                SmallCollPointInfo* collPts = stackalloc SmallCollPointInfo[MaxLocalStackSCPI];
                int* potentialTriangles = stackalloc int[MaxLocalStackTris];
                {
                    {
            #else
                SmallCollPointInfo[] collPtArray = SCPIStackAlloc();
                fixed (SmallCollPointInfo* collPts = collPtArray)
                {
                    int[] potTriArray = IntStackAlloc();
                    fixed( int* potentialTriangles = potTriArray)
                    {
            #endif
                        int numCollPts = 0;

                        Vector3 collNormal = Vector3.Zero;

                        BoundingBox bb = BoundingBoxHelper.InitialBox;
                        BoundingBoxHelper.AddSphere(newSphere, ref bb);
                        int numTriangles = mesh.GetTrianglesIntersectingtAABox(potentialTriangles, MaxLocalStackTris, ref bb);

                        // Deano : get the spheres centers in triangle mesh space
                        Vector3 newSphereCen = Vector3.Transform(newSphere.Center, mesh.InverseTransformMatrix);
                        Vector3 oldSphereCen = Vector3.Transform(oldSphere.Center, mesh.InverseTransformMatrix);

                        for (int iTriangle = 0; iTriangle < numTriangles; ++iTriangle)
                        {
                            IndexedTriangle meshTriangle = mesh.GetTriangle(potentialTriangles[iTriangle]);
                            float distToCentre = meshTriangle.Plane.DotCoordinate(newSphereCen);

                            if (distToCentre <= 0.0f)
                                continue;
                            if (distToCentre >= sphereTolR)
                                continue;
                            int i0, i1, i2;
                            meshTriangle.GetVertexIndices(out i0, out i1, out i2);

                            Triangle triangle = new Triangle(mesh.GetVertex(i0), mesh.GetVertex(i1), mesh.GetVertex(i2));

                            float s, t;
                            float newD2 = Distance.PointTriangleDistanceSq(out s, out t, newSphereCen, triangle);

                            if (newD2 < sphereTolR2)
                            {
                                // have overlap - but actually report the old intersection
                                float oldD2 = Distance.PointTriangleDistanceSq(out s, out t, oldSphereCen, triangle);
                                float dist = (float)System.Math.Sqrt((float)oldD2);
                                float depth = oldSphere.Radius - dist;

                                Vector3 triPointSTNorm = oldSphereCen - triangle.GetPoint(s, t);
                                JiggleMath.NormalizeSafe(ref triPointSTNorm);

                                Vector3 collisionN = (dist > float.Epsilon) ? triPointSTNorm : triangle.Normal;

                                // since impulse get applied at the old position
                                Vector3 pt = oldSphere.Center - oldSphere.Radius * collisionN;

                                if (numCollPts < MaxLocalStackSCPI)
                                {
                                    collPts[numCollPts++] = new SmallCollPointInfo(pt - body0Pos, pt - body1Pos, depth);
                                }
                                collNormal += collisionN;
                            }
                        }

                        if (numCollPts > 0)
                        {
                            JiggleMath.NormalizeSafe(ref collNormal);
                            collisionFunctor.CollisionNotify(ref info, ref collNormal, collPts, numCollPts);
                        }
            #if USE_STACKALLOC
                    }
               }
            #else

                        FreeStackAlloc(potTriArray);
                    }
                    FreeStackAlloc(collPtArray);
                }
            #endif
            }
        }
Exemplo n.º 3
0
        /// <summary>
        /// DoOverlapBoxTriangleTest
        /// </summary>
        /// <param name="oldBox"></param>
        /// <param name="newBox"></param>
        /// <param name="triangle"></param>
        /// <param name="mesh"></param>
        /// <param name="info"></param>
        /// <param name="collTolerance"></param>
        /// <param name="collisionFunctor"></param>
        /// <returns>bool</returns>
        private static bool DoOverlapBoxTriangleTest(Box oldBox, Box newBox,
            ref IndexedTriangle triangle, TriangleMesh mesh,
            ref CollDetectInfo info, float collTolerance,
            CollisionFunctor collisionFunctor)
        {
            Matrix4 dirs0 = newBox.Orientation;

            #region REFERENCE: Triangle tri = new Triangle(mesh.GetVertex(triangle.GetVertexIndex(0)),mesh.GetVertex(triangle.GetVertexIndex(1)),mesh.GetVertex(triangle.GetVertexIndex(2)));
            Vector3 triVec0;
            Vector3 triVec1;
            Vector3 triVec2;
            mesh.GetVertex(triangle.GetVertexIndex(0), out triVec0);
            mesh.GetVertex(triangle.GetVertexIndex(1), out triVec1);
            mesh.GetVertex(triangle.GetVertexIndex(2), out triVec2);

            // Deano move tri into world space
            Matrix4 transformMatrix = mesh.TransformMatrix;
            Vector3.Transform(ref triVec0, ref transformMatrix, out triVec0);
            Vector3.Transform(ref triVec1, ref transformMatrix, out triVec1);
            Vector3.Transform(ref triVec2, ref transformMatrix, out triVec2);

            Triangle tri = new Triangle(ref triVec0,ref triVec1,ref triVec2);
            #endregion

            #region REFERENCE Vector3 triEdge0 = (tri.GetPoint(1) - tri.GetPoint(0));
            Vector3 pt0;
            Vector3 pt1;
            tri.GetPoint(0, out pt0);
            tri.GetPoint(1, out pt1);

            Vector3 triEdge0;
            Vector3.Subtract(ref pt1, ref pt0, out triEdge0);
            #endregion

            #region REFERENCE Vector3 triEdge1 = (tri.GetPoint(2) - tri.GetPoint(1));
            Vector3 pt2;
            tri.GetPoint(2, out pt2);

            Vector3 triEdge1;
            Vector3.Subtract(ref pt2, ref pt1, out triEdge1);
            #endregion

            #region REFERENCE Vector3 triEdge2 = (tri.GetPoint(0) - tri.GetPoint(2));
            Vector3 triEdge2;
            Vector3.Subtract(ref pt0, ref pt2, out triEdge2);
            #endregion

            triEdge0.Normalize();
            triEdge1.Normalize();
            triEdge2.Normalize();

            // BEN-OPTIMISATION: Replaced loops with code that requires no looping.
            //                   The new code is faster, has less allocations and math especially
            //                   since the method returns as soon as it finds a non-overlapping axis,
            //                   i.e. Before irreleveat allocations occur.
            #region "Old (less efficient) code"
            /*Vector3 triNormal = triangle.Plane.Normal;

            // the 15 potential separating axes
            const int numAxes = 13;
            Vector3[] axes = new Vector3[numAxes];

            axes[0] = triNormal;
            axes[1] = dirs0.Right;
            axes[2] = dirs0.Up;
            axes[3] = dirs0.Backward;
            Vector3.Cross(ref axes[1], ref triEdge0, out axes[4]);
            Vector3.Cross(ref axes[1], ref triEdge1, out axes[5]);
            Vector3.Cross(ref axes[1], ref triEdge2, out axes[6]);
            Vector3.Cross(ref axes[2], ref triEdge0, out axes[7]);
            Vector3.Cross(ref axes[2], ref triEdge1, out axes[8]);
            Vector3.Cross(ref axes[2], ref triEdge2, out axes[9]);
            Vector3.Cross(ref axes[3], ref triEdge0, out axes[10]);
            Vector3.Cross(ref axes[3], ref triEdge1, out axes[11]);
            Vector3.Cross(ref axes[3], ref triEdge2, out axes[12]);

            // the overlap depths along each axis
            float[] overlapDepths = new float[numAxes];

            // see if the boxes are separate along any axis, and if not keep a
            // record of the depths along each axis
            int i;
            for (i = 0; i < numAxes; ++i)
            {
                overlapDepths[i] = 1.0f;
                if (Disjoint(out overlapDepths[i], axes[i], newBox, tri, collTolerance))
                    return false;
            }

            // The box overlap, find the separation depth closest to 0.
            float minDepth = float.MaxValue;
            int minAxis = -1;

            for (i = 0; i < numAxes; ++i)
            {
                // If we can't normalise the axis, skip it
                float l2 = axes[i].LengthSquared;
                if (l2 < JiggleMath.Epsilon)
                    continue;

                // Normalise the separation axis and the depth
                float invl = 1.0f / (float)System.Math.Sqrt(l2);
                axes[i] *= invl;
                overlapDepths[i] *= invl;

                // If this axis is the minimum, select it
                if (overlapDepths[i] < minDepth)
                {
                    minDepth = overlapDepths[i];
                    minAxis = i;
                }
            }

            if (minAxis == -1)
                return false;

            // Make sure the axis is facing towards the 0th box.
            // if not, invert it
            Vector3 D = newBox.GetCentre() - tri.Centre;
            Vector3 N = axes[minAxis];
            float depth = overlapDepths[minAxis];*/
            #endregion
            #region "Optimised code"
            Vector3 triNormal = triangle.Plane.Normal;
            Vector3 right = dirs0.Right();
            Vector3 up = dirs0.Up();
            Vector3 backward = dirs0.Backward();

            float testDepth;

            if (Disjoint(out testDepth, ref triNormal, newBox, ref tri, collTolerance))
                return (false);

            float depth = testDepth;
            Vector3 N = triNormal;

            if (Disjoint(out testDepth, ref right, newBox, ref tri, collTolerance))
                return (false);

            if (testDepth < depth)
            {
                depth = testDepth;
                N = right;
            }

            if (Disjoint(out testDepth, ref up, newBox, ref tri, collTolerance))
                return (false);

            if (testDepth < depth)
            {
                depth = testDepth;
                N = up;
            }

            if (Disjoint(out testDepth, ref backward, newBox, ref tri, collTolerance))
                return (false);

            if (testDepth < depth)
            {
                depth = testDepth;
                N = backward;
            }

            Vector3 axis;

            Vector3.Cross(ref right, ref triEdge0, out axis);
            if (Disjoint(out testDepth, ref axis, newBox, ref tri, collTolerance))
                return (false);

            testDepth *= 1.0f / (float)System.Math.Sqrt(axis.X * axis.X + axis.Y * axis.Y + axis.Z * axis.Z);
            if (testDepth < depth)
            {
                depth = testDepth;
                N = axis;
            }

            Vector3.Cross(ref right, ref triEdge1, out axis);
            if (Disjoint(out testDepth, ref axis, newBox, ref tri, collTolerance))
                return (false);

            testDepth *= 1.0f / (float)System.Math.Sqrt(axis.X * axis.X + axis.Y * axis.Y + axis.Z * axis.Z);
            if (testDepth < depth)
            {
                depth = testDepth;
                N = axis;
            }

            Vector3.Cross(ref right, ref triEdge2, out axis);
            if (Disjoint(out testDepth, ref axis, newBox, ref tri, collTolerance))
                return (false);

            testDepth *= 1.0f / (float)System.Math.Sqrt(axis.X * axis.X + axis.Y * axis.Y + axis.Z * axis.Z);
            if (testDepth < depth)
            {
                depth = testDepth;
                N = axis;
            }

            Vector3.Cross(ref up, ref triEdge0, out axis);
            if (Disjoint(out testDepth, ref axis, newBox, ref tri, collTolerance))
                return (false);

            testDepth *= 1.0f / (float)System.Math.Sqrt(axis.X * axis.X + axis.Y * axis.Y + axis.Z * axis.Z);
            if (testDepth < depth)
            {
                depth = testDepth;
                N = axis;
            }

            Vector3.Cross(ref up, ref triEdge1, out axis);
            if (Disjoint(out testDepth, ref axis, newBox, ref tri, collTolerance))
                return (false);

            testDepth *= 1.0f / (float)System.Math.Sqrt(axis.X * axis.X + axis.Y * axis.Y + axis.Z * axis.Z);
            if (testDepth < depth)
            {
                depth = testDepth;
                N = axis;
            }

            Vector3.Cross(ref up, ref triEdge2, out axis);
            if (Disjoint(out testDepth, ref axis, newBox, ref tri, collTolerance))
                return (false);

            testDepth *= 1.0f / (float)System.Math.Sqrt(axis.X * axis.X + axis.Y * axis.Y + axis.Z * axis.Z);
            if (testDepth < depth)
            {
                depth = testDepth;
                N = axis;
            }

            Vector3.Cross(ref backward, ref triEdge0, out axis);
            if (Disjoint(out testDepth, ref axis, newBox, ref tri, collTolerance))
                return (false);

            testDepth *= 1.0f / (float)System.Math.Sqrt(axis.X * axis.X + axis.Y * axis.Y + axis.Z * axis.Z);
            if (testDepth < depth)
            {
                depth = testDepth;
                N = axis;
            }

            Vector3.Cross(ref backward, ref triEdge1, out axis);
            if (Disjoint(out testDepth, ref axis, newBox, ref tri, collTolerance))
                return (false);

            testDepth *= 1.0f / (float)System.Math.Sqrt(axis.X * axis.X + axis.Y * axis.Y + axis.Z * axis.Z);
            if (testDepth < depth)
            {
                depth = testDepth;
                N = axis;
            }

            Vector3.Cross(ref backward, ref triEdge2, out axis);
            if (Disjoint(out testDepth, ref axis, newBox, ref tri, collTolerance))
                return (false);

            testDepth *= 1.0f / (float)System.Math.Sqrt(axis.X * axis.X + axis.Y * axis.Y + axis.Z * axis.Z);
            if (testDepth < depth)
            {
                depth = testDepth;
                N = axis;
            }

            /*if (N == Vector3.Zero)
                return (false);*/

            Vector3 D = newBox.GetCentre() - tri.Centre;
            N.Normalize();
            int i;

            #endregion

            if (Vector3.Dot(D, N) < 0.0f)
               N *= -1;

            Vector3 boxOldPos = (info.Skin0.Owner != null) ? info.Skin0.Owner.OldPosition : Vector3.Zero;
            Vector3 boxNewPos = (info.Skin0.Owner != null) ? info.Skin0.Owner.Position : Vector3.Zero;
            Vector3 meshPos = (info.Skin1.Owner != null) ? info.Skin1.Owner.OldPosition : Vector3.Zero;

            List<Vector3> pts = new List<Vector3>();
            //pts.Clear();

            const float combinationDist = 0.05f;
            GetBoxTriangleIntersectionPoints(pts, newBox, tri, depth + combinationDist);

            // adjust the depth
            #region REFERENCE: Vector3 delta = boxNewPos - boxOldPos;
            Vector3 delta;
            Vector3.Subtract(ref boxNewPos, ref boxOldPos, out delta);
            #endregion

            #region REFERENCE: float oldDepth = depth + Vector3.Dot(delta, N);
            float oldDepth;
            Vector3.Dot(ref delta, ref N, out oldDepth);
            oldDepth += depth;
            #endregion

            unsafe
            {
                // report collisions
                int numPts = pts.Count;
            #if USE_STACKALLOC
                SmallCollPointInfo* collPts = stackalloc SmallCollPointInfo[MaxLocalStackSCPI];
            #else
                SmallCollPointInfo[] collPtArray = SCPIStackAlloc();
                fixed (SmallCollPointInfo* collPts = collPtArray)
            #endif
                {
                    if (numPts > 0)
                    {
                        if (numPts >= MaxLocalStackSCPI)
                        {
                            numPts = MaxLocalStackSCPI - 1;
                        }

                        // adjust positions
                        for (i = 0; i < numPts; ++i)
                        {
                            // BEN-OPTIMISATION: Reused existing SmallCollPointInfo and inlined vector substraction.
                            collPts[i].R0.X = pts[i].X - boxNewPos.X;
                            collPts[i].R0.Y = pts[i].Y - boxNewPos.Y;
                            collPts[i].R0.Z = pts[i].Z - boxNewPos.Z;

                            collPts[i].R1.X = pts[i].X - meshPos.X;
                            collPts[i].R1.Y = pts[i].Y - meshPos.Y;
                            collPts[i].R1.Z = pts[i].Z - meshPos.Z;

                            collPts[i].InitialPenetration = oldDepth;
                        }

                        collisionFunctor.CollisionNotify(ref info, ref N, collPts, numPts);
            #if !USE_STACKALLOC
                        FreeStackAlloc(collPtArray);
            #endif
                        return true;
                    }
                    else
                    {
            #if !USE_STACKALLOC
                        FreeStackAlloc(collPtArray);
            #endif
                        return false;
                    }
                }

            }
        }
Exemplo n.º 4
0
        /// <summary>
        /// CollDetectCapsuleStaticMeshOverlap
        /// </summary>
        /// <param name="oldCapsule"></param>
        /// <param name="newCapsule"></param>
        /// <param name="mesh"></param>
        /// <param name="info"></param>
        /// <param name="collTolerance"></param>
        /// <param name="collisionFunctor"></param>
        private void CollDetectCapsuleStaticMeshOverlap(Capsule oldCapsule, Capsule newCapsule,
            TriangleMesh mesh, CollDetectInfo info, float collTolerance, CollisionFunctor collisionFunctor)
        {
            Vector3 body0Pos = (info.Skin0.Owner != null) ? info.Skin0.Owner.OldPosition : Vector3.Zero;
            Vector3 body1Pos = (info.Skin1.Owner != null) ? info.Skin1.Owner.OldPosition : Vector3.Zero;

            float capsuleTolR = collTolerance + newCapsule.Radius;
            float capsuleTolR2 = capsuleTolR * capsuleTolR;

            Vector3 collNormal = Vector3.Zero;

            BoundingBox bb = BoundingBoxHelper.InitialBox;
            BoundingBoxHelper.AddCapsule(newCapsule, ref bb);

            unsafe
            {
            #if USE_STACKALLOC
                SmallCollPointInfo* collPts = stackalloc SmallCollPointInfo[MaxLocalStackSCPI];
                int* potentialTriangles = stackalloc int[MaxLocalStackTris];
                {
                    {
            #else
                SmallCollPointInfo[] collPtArray = SCPIStackAlloc();
                fixed (SmallCollPointInfo* collPts = collPtArray)
                {
                    int[] potTriArray = IntStackAlloc();
                    fixed (int* potentialTriangles = potTriArray)
                    {
            #endif
                        int numCollPts = 0;

                        int numTriangles = mesh.GetTrianglesIntersectingtAABox(potentialTriangles, MaxLocalStackTris, ref bb);

                        Vector3 capsuleStart = newCapsule.Position;
                        Vector3 capsuleEnd = newCapsule.GetEnd();
                        Matrix4 meshInvTransform = mesh.InverseTransformMatrix;

                        Vector3 meshSpaceCapsuleStart = Vector3.Transform(capsuleStart, meshInvTransform);
                        Vector3 meshSpaceCapsuleEnd = Vector3.Transform(capsuleEnd, meshInvTransform);

                        for (int iTriangle = 0; iTriangle < numTriangles; ++iTriangle)
                        {
                            IndexedTriangle meshTriangle = mesh.GetTriangle(potentialTriangles[iTriangle]);

                            // we do the plane test using the capsule in mesh space
                            float distToStart = meshTriangle.Plane.DotCoordinate(meshSpaceCapsuleStart);
                            float distToEnd = meshTriangle.Plane.DotCoordinate(meshSpaceCapsuleEnd);

                            // BEN-BUG-FIX: Fixed by replacing 0.0F with -capsuleTolR.
                            if ((distToStart > capsuleTolR && distToEnd > capsuleTolR)
                                || (distToStart < -capsuleTolR && distToEnd < -capsuleTolR))
                                continue;

                            // we now transform the triangle into world space (we could keep leave the mesh alone
                            // but at this point 3 vector transforms is probably not a major slow down)
                            int i0, i1, i2;
                            meshTriangle.GetVertexIndices(out i0, out i1, out i2);

                            Vector3 triVec0;
                            Vector3 triVec1;
                            Vector3 triVec2;
                            mesh.GetVertex(i0, out triVec0);
                            mesh.GetVertex(i1, out triVec1);
                            mesh.GetVertex(i2, out triVec2);

                            // Deano move tri into world space
                            Matrix4 transformMatrix = mesh.TransformMatrix;
                            Vector3.Transform(ref triVec0, ref transformMatrix, out triVec0);
                            Vector3.Transform(ref triVec1, ref transformMatrix, out triVec1);
                            Vector3.Transform(ref triVec2, ref transformMatrix, out triVec2);
                            Triangle triangle = new Triangle(ref triVec0, ref triVec1, ref triVec2);

                            Segment seg = new Segment(capsuleStart, capsuleEnd - capsuleStart);

                            float tS, tT0, tT1;
                            float d2 = Distance.SegmentTriangleDistanceSq(out tS, out tT0, out tT1, seg, triangle);

                            if (d2 < capsuleTolR2)
                            {
                                Vector3 oldCapsuleStart = oldCapsule.Position;
                                Vector3 oldCapsuleEnd = oldCapsule.GetEnd();
                                Segment oldSeg = new Segment(oldCapsuleStart, oldCapsuleEnd - oldCapsuleStart);
                                d2 = Distance.SegmentTriangleDistanceSq(out tS, out tT0, out tT1, oldSeg, triangle);
                                // report result from old position
                                float dist = (float)System.Math.Sqrt(d2);
                                float depth = oldCapsule.Radius - dist;
                                Vector3 pt = triangle.GetPoint(tT0, tT1);
                                Vector3 collisionN = (d2 > JiggleMath.Epsilon) ? JiggleMath.NormalizeSafe(oldSeg.GetPoint(tS) - pt) :
                                    meshTriangle.Plane.Normal;
                                if (numCollPts < MaxLocalStackSCPI)
                                {
                                    // BEN-OPTIMISATION: Reused existing collPts.
                                    collPts[numCollPts].R0 = pt - body0Pos;
                                    collPts[numCollPts].R1 = pt - body1Pos;
                                    collPts[numCollPts++].InitialPenetration = depth;
                                }
                                collNormal += collisionN;
                            }
                        }
                        if (numCollPts > 0)
                        {
                            JiggleMath.NormalizeSafe(ref collNormal);
                            collisionFunctor.CollisionNotify(ref info, ref collNormal, collPts, numCollPts);
                        }
            #if USE_STACKALLOC
                    }
               }
            #else
                    }
                    FreeStackAlloc(potTriArray);
                }
                FreeStackAlloc(collPtArray);
            #endif
            }
        }
Exemplo n.º 5
0
        internal static void CollDetectSphereStaticMeshSweep(BoundingSphere oldSphere, BoundingSphere newSphere, TriangleMesh mesh,
            CollDetectInfo info, float collTolerance, CollisionFunctor collisionFunctor)
        {
            // really use a swept test - or overlap?
            Vector3 delta = newSphere.Center - oldSphere.Center;
            if (delta.LengthSquared() < (0.25f * newSphere.Radius * newSphere.Radius))
            {
                CollDetectSphereStaticMeshOverlap(oldSphere, newSphere, mesh, info, collTolerance, collisionFunctor);
            }
            else
            {
                Vector3 body0Pos = (info.Skin0.Owner != null) ? info.Skin0.Owner.OldPosition : Vector3.Zero;
                Vector3 body1Pos = (info.Skin1.Owner != null) ? info.Skin1.Owner.OldPosition : Vector3.Zero;

                float sphereTolR = collTolerance + oldSphere.Radius;
                float sphereToR2 = sphereTolR * sphereTolR;

                Vector3 collNormal = Vector3.Zero;

                BoundingBox bb = BoundingBoxHelper.InitialBox;
                BoundingBoxHelper.AddSphere(oldSphere, ref bb);
                BoundingBoxHelper.AddSphere(newSphere, ref bb);

                // get the spheres centers in triangle mesh space
                Vector3 newSphereCen = Vector3.Transform(newSphere.Center, mesh.InverseTransformMatrix);
                Vector3 oldSphereCen = Vector3.Transform(oldSphere.Center, mesh.InverseTransformMatrix);

                unsafe
                {
            #if USE_STACKALLOC
                    SmallCollPointInfo* collPts = stackalloc SmallCollPointInfo[MaxLocalStackSCPI];
                    int* potentialTriangles = stackalloc int[MaxLocalStackTris];
                    {
                        {
            #else
                    SmallCollPointInfo[] collPtArray = SCPIStackAlloc();
                    fixed (SmallCollPointInfo* collPts = collPtArray)
                    {
                        int[] potTriArray = IntStackAlloc();
                        fixed( int* potentialTriangles = potTriArray)
                        {
            #endif
                            int numCollPts = 0;

                            int numTriangles = mesh.GetTrianglesIntersectingtAABox(potentialTriangles, MaxLocalStackTris, ref bb);

                            for (int iTriangle = 0; iTriangle < numTriangles; ++iTriangle)
                            {

                                // first test the old sphere for being on the wrong side
                                IndexedTriangle meshTriangle = mesh.GetTriangle(potentialTriangles[iTriangle]);
                                float distToCentreOld = meshTriangle.Plane.DotCoordinate(oldSphereCen);
                                if (distToCentreOld <= 0.0f)
                                    continue;
                                // now test the new sphere for being clear

                                float distToCentreNew = meshTriangle.Plane.DotCoordinate(newSphereCen);
                                if (distToCentreNew > sphereTolR)
                                    continue;

                                int i0, i1, i2;
                                meshTriangle.GetVertexIndices(out i0, out i1, out i2);

                                Triangle triangle = new Triangle(mesh.GetVertex(i0), mesh.GetVertex(i1), mesh.GetVertex(i2));

                                // If the old sphere is intersecting, just use that result
                                float s, t;
                                float d2 = Distance.PointTriangleDistanceSq(out s, out t, oldSphereCen, triangle);

                                if (d2 < sphereToR2)
                                {
                                    float dist = (float)System.Math.Sqrt(d2);
                                    float depth = oldSphere.Radius - dist;
                                    Vector3 triangleN = triangle.Normal;
                                    Vector3 normSafe = oldSphereCen - triangle.GetPoint(s, t);

                                    JiggleMath.NormalizeSafe(ref normSafe);

                                    Vector3 collisionN = (dist > float.Epsilon) ? normSafe : triangleN;
                                    // since impulse gets applied at the old position
                                    Vector3 pt = oldSphere.Center - oldSphere.Radius * collisionN;
                                    if (numCollPts < MaxLocalStackSCPI)
                                    {
                                        collPts[numCollPts++] = new SmallCollPointInfo(pt - body0Pos, pt - body1Pos, depth);
                                    }
                                    collNormal += collisionN;
                                }
                                else if (distToCentreNew < distToCentreOld)
                                {
                                    // old sphere is not intersecting - do a sweep, but only if the sphere is moving into the
                                    // triangle
                                    Vector3 pt, N; // CHECK THIS
                                    float depth;
                                    if (Intersection.SweptSphereTriangleIntersection(out pt, out N, out depth, oldSphere, newSphere, triangle,
                                        distToCentreOld, distToCentreNew, Intersection.EdgesToTest.EdgeAll, Intersection.CornersToTest.CornerAll))
                                    {
                                        // collision point etc must be relative to the old position because that's
                                        //where the impulses are applied
                                        float dist = (float)System.Math.Sqrt(d2);
                                        float depth2 = oldSphere.Radius - dist;
                                        Vector3 triangleN = triangle.Normal;
                                        Vector3 normSafe = oldSphereCen - triangle.GetPoint(s, t);
                                        JiggleMath.NormalizeSafe(ref normSafe);
                                        Vector3 collisionN = (dist > JiggleMath.Epsilon) ? normSafe : triangleN;
                                        // since impulse gets applied at the old position
                                        Vector3 pt2 = oldSphere.Center - oldSphere.Radius * collisionN;
                                        if (numCollPts < MaxLocalStackSCPI)
                                        {
                                            collPts[numCollPts++] = new SmallCollPointInfo(pt2 - body0Pos, pt2 - body1Pos, depth);
                                        }
                                        collNormal += collisionN;
                                    }
                                }
                            }
                            if (numCollPts > 0)
                            {
                                JiggleMath.NormalizeSafe(ref collNormal);
                                collisionFunctor.CollisionNotify(ref info, ref collNormal, collPts, numCollPts);
                            }
                        }
            #if USE_STACKALLOC
                    }
               }
            #else

                        FreeStackAlloc(potTriArray);
                    }
                    FreeStackAlloc(collPtArray);
                }
            #endif
            }
        }
Exemplo n.º 6
0
        public static bool SweptSphereTriangleIntersection(out Vector3 pt, out Vector3 N, out float depth,
                                                           BoundingSphere oldSphere, BoundingSphere newSphere, Triangle triangle,
                                                           float oldCentreDistToPlane, float newCentreDistToPlane,
                                                           EdgesToTest edgesToTest, CornersToTest cornersToTest)
        {
            int i;

            Microsoft.Xna.Framework.Plane trianglePlane = triangle.Plane;
            N = Vector3.Zero;

            // Check against plane
            if (!SweptSpherePlaneIntersection(out pt, out depth, oldSphere, newSphere, trianglePlane.Normal, oldCentreDistToPlane, newCentreDistToPlane))
            {
                return(false);
            }

            Vector3 v0 = triangle.GetPoint(0);
            Vector3 v1 = triangle.GetPoint(1);
            Vector3 v2 = triangle.GetPoint(2);

            Vector3 e0 = v1 - v0;
            Vector3 e1 = v2 - v1;
            Vector3 e2 = v0 - v2;

            // If the point is inside the triangle, this is a hit
            bool    allInside = true;
            Vector3 outDir0   = Vector3.Cross(e0, trianglePlane.Normal);

            if (Vector3.Dot(pt - v0, outDir0) > 0.0f)
            {
                allInside = false;
            }
            Vector3 outDir1 = Vector3.Cross(e1, trianglePlane.Normal);

            if (Vector3.Dot(pt - v1, outDir1) > 0.0f)
            {
                allInside = false;
            }
            Vector3 outDir2 = Vector3.Cross(e2, trianglePlane.Normal);

            if (Vector3.Dot(pt - v2, outDir2) > 0.0f)
            {
                allInside = false;
            }

            // Quick result?
            if (allInside)
            {
                N = trianglePlane.Normal;
                return(true);
            }

            // Now check against the edges
            float   bestT    = float.MaxValue;
            Vector3 Ks       = newSphere.Center - oldSphere.Center;
            float   kss      = Vector3.Dot(Ks, Ks);
            float   radius   = newSphere.Radius;
            float   radiusSq = radius * radius;

            for (i = 0; i < 3; ++i)
            {
                int mask = 1 << i;
                if (!((mask != 0) & ((int)edgesToTest != 0))) // TODO: CHECK THIS
                {
                    continue;
                }
                Vector3 Ke;
                Vector3 vp;

                switch (i)
                {
                case 0:
                    Ke = e0;
                    vp = v0;
                    break;

                case 1:
                    Ke = e1;
                    vp = v1;
                    break;

                case 2:
                default:
                    Ke = e2;
                    vp = v2;
                    break;
                }
                Vector3 Kg = vp - oldSphere.Center;

                float kee = Vector3.Dot(Ke, Ke);
                if (System.Math.Abs(kee) < JiggleMath.Epsilon)
                {
                    continue;
                }
                float kes = Vector3.Dot(Ke, Ks);
                float kgs = Vector3.Dot(Kg, Ks);
                float keg = Vector3.Dot(Ke, Kg);
                float kgg = Vector3.Dot(Kg, Kg);

                // a * t^2 + b * t + c = 0
                float a = kee * kss - (kes * kes);
                if (System.Math.Abs(a) < JiggleMath.Epsilon)
                {
                    continue;
                }
                float b = 2.0f * (keg * kes - kee * kgs);
                float c = kee * (kgg - radiusSq) - keg * keg;

                float blah = b * b - 4.0f * a * c;
                if (blah < 0.0f)
                {
                    continue;
                }

                // solve for t - take minimum
                float t = (-b - (float)System.Math.Sqrt(blah)) / (2.0f * a);

                if (t < 0.0f || t > 1.0f)
                {
                    continue;
                }

                if (t > bestT)
                {
                    continue;
                }

                // now check where it hit on the edge
                Vector3 Ct = oldSphere.Center + t * Ks;
                float   d  = Vector3.Dot((Ct - vp), Ke) / kee;

                if (d < 0.0f || d > 1.0f)
                {
                    continue;
                }

                // wahay - got hit. Already checked that t < bestT
                bestT = t;

                pt = vp + d * Ke;
                N  = (Ct - pt);// .GetNormalisedSafe();
                JiggleMath.NormalizeSafe(ref N);
                // depth is already calculated
            }
            if (bestT <= 1.0f)
            {
                return(true);
            }

            // check the corners
            bestT = float.MaxValue;
            for (i = 0; i < 3; ++i)
            {
                int mask = 1 << i;
                if (!((mask != 0) & (cornersToTest != 0))) // CHECK THIS
                {
                    continue;
                }
                Vector3 vp;

                switch (i)
                {
                case 0:
                    vp = v0;
                    break;

                case 1:
                    vp = v1;
                    break;

                case 2:
                default:
                    vp = v2;
                    break;
                }
                Vector3 Kg  = vp - oldSphere.Center;
                float   kgs = Vector3.Dot(Kg, Ks);
                float   kgg = Vector3.Dot(Kg, Kg);
                float   a   = kss;
                if (System.Math.Abs(a) < JiggleMath.Epsilon)
                {
                    continue;
                }
                float b = -2.0f * kgs;
                float c = kgg - radiusSq;

                float blah = (b * b) - 4.0f * a * c;
                if (blah < 0.0f)
                {
                    continue;
                }

                // solve for t - take minimum
                float t = (-b - (float)System.Math.Sqrt(blah)) / (2.0f * a);

                if (t < 0.0f || t > 1.0f)
                {
                    continue;
                }

                if (t > bestT)
                {
                    continue;
                }

                bestT = t;

                Vector3 Ct = oldSphere.Center + t * Ks;
                N = (Ct - vp);//.GetNormalisedSafe();
                JiggleMath.NormalizeSafe(ref N);
            }
            if (bestT <= 1.0f)
            {
                return(true);
            }

            return(false);
        }
Exemplo n.º 7
0
        /// <summary>
        /// GetBoxTriangleIntersectionPoints
        /// Pushes intersection points onto the back of pts. Returns the
        /// number of points found.
        /// Points that are close together (compared to 
        /// combinationDistance) get combined
        /// </summary>
        /// <param name="pts"></param>
        /// <param name="box"></param>
        /// <param name="triangle"></param>
        /// <param name="combinationDistance"></param>
        /// <returns></returns>
        private static int GetBoxTriangleIntersectionPoints(List<Vector3> pts, Box box, Triangle triangle, float combinationDistance)
        {
            // first intersect each edge of the box with the triangle
            Box.Edge[] edges;
            box.GetEdges(out edges);
            Vector3[] boxPts;
            box.GetCornerPoints(out boxPts);

            float tS;
            float tv1, tv2;

            int iEdge;
            for (iEdge = 0; iEdge < 12; ++iEdge)
            {
                Box.Edge edge = edges[iEdge];
                Segment seg = new Segment(boxPts[(int)edge.Ind0], boxPts[(int)edge.Ind1] - boxPts[(int)edge.Ind0]);
                if (Intersection.SegmentTriangleIntersection(out tS, out tv1, out tv2, seg, triangle))
                {
                     AddPoint(pts, seg.GetPoint(tS), combinationDistance * combinationDistance);
                }
            }

            Vector3 pos, n;
            // now each edge of the triangle with the box
            for (iEdge = 0; iEdge < 3; ++iEdge)
            {
                Vector3 pt0 = triangle.GetPoint(iEdge);
                Vector3 pt1 = triangle.GetPoint((iEdge + 1) % 3);
                Segment s1 = new Segment(pt0, pt1 - pt0);
                Segment s2 = new Segment(pt1, pt0 - pt1);
                if (box.SegmentIntersect(out tS, out pos, out n, s1))
                    AddPoint(pts, pos, combinationDistance * combinationDistance);
                if (box.SegmentIntersect(out tS, out pos, out n, s2))
                    AddPoint(pts, pos, combinationDistance * combinationDistance);
            }

            return pts.Count;
        }
Exemplo n.º 8
0
        private static bool DoOverlapBoxTriangleTest(Box oldBox, Box newBox,
            ref IndexedTriangle triangle, TriangleMesh mesh,
            ref CollDetectInfo info, float collTolerance,
            CollisionFunctor collisionFunctor)
        {
            Matrix dirs0 = newBox.Orientation;

            #region REFERENCE: Triangle tri = new Triangle(mesh.GetVertex(triangle.GetVertexIndex(0)),mesh.GetVertex(triangle.GetVertexIndex(1)),mesh.GetVertex(triangle.GetVertexIndex(2)));
            Vector3 triVec0;
            Vector3 triVec1;
            Vector3 triVec2;
            mesh.GetVertex(triangle.GetVertexIndex(0), out triVec0);
            mesh.GetVertex(triangle.GetVertexIndex(1), out triVec1);
            mesh.GetVertex(triangle.GetVertexIndex(2), out triVec2);

            // Deano move tri into world space
            Matrix transformMatrix = mesh.TransformMatrix;
            Vector3.Transform(ref triVec0, ref transformMatrix, out triVec0);
            Vector3.Transform(ref triVec1, ref transformMatrix, out triVec1);
            Vector3.Transform(ref triVec2, ref transformMatrix, out triVec2);

            Triangle tri = new Triangle(ref triVec0,ref triVec1,ref triVec2);
            #endregion

            #region REFERENCE Vector3 triEdge0 = (tri.GetPoint(1) - tri.GetPoint(0));
            Vector3 pt0;
            Vector3 pt1;
            tri.GetPoint(0, out pt0);
            tri.GetPoint(1, out pt1);

            Vector3 triEdge0;
            Vector3.Subtract(ref pt1, ref pt0, out triEdge0);
            #endregion

            #region REFERENCE Vector3 triEdge1 = (tri.GetPoint(2) - tri.GetPoint(1));
            Vector3 pt2;
            tri.GetPoint(2, out pt2);

            Vector3 triEdge1;
            Vector3.Subtract(ref pt2, ref pt1, out triEdge1);
            #endregion

            #region REFERENCE Vector3 triEdge2 = (tri.GetPoint(0) - tri.GetPoint(2));
            Vector3 triEdge2;
            Vector3.Subtract(ref pt0, ref pt2, out triEdge2);
            #endregion

            triEdge0.Normalize();
            triEdge1.Normalize();
            triEdge2.Normalize();

            Vector3 triNormal = triangle.Plane.Normal;

            // the 15 potential separating axes
            const int numAxes = 13;
            Vector3[] axes = new Vector3[numAxes];

            axes[0] = triNormal;
            axes[1] = dirs0.Right;
            axes[2] = dirs0.Up;
            axes[3] = dirs0.Backward;
            Vector3.Cross(ref axes[1], ref triEdge0, out axes[4]);
            Vector3.Cross(ref axes[1], ref triEdge1, out axes[5]);
            Vector3.Cross(ref axes[1], ref triEdge2, out axes[6]);
            Vector3.Cross(ref axes[2], ref triEdge0, out axes[7]);
            Vector3.Cross(ref axes[2], ref triEdge1, out axes[8]);
            Vector3.Cross(ref axes[2], ref triEdge2, out axes[9]);
            Vector3.Cross(ref axes[3], ref triEdge0, out axes[10]);
            Vector3.Cross(ref axes[3], ref triEdge1, out axes[11]);
            Vector3.Cross(ref axes[3], ref triEdge2, out axes[12]);

            // the overlap depths along each axis
            float[] overlapDepths = new float[numAxes];

            // see if the boxes are separate along any axis, and if not keep a
            // record of the depths along each axis
            int i;
            for (i = 0; i < numAxes; ++i)
            {
                overlapDepths[i] = 1.0f;
                if (Disjoint(out overlapDepths[i], axes[i], newBox, tri, collTolerance))
                    return false;
            }

            // The box overlap, find the separation depth closest to 0.
            float minDepth = float.MaxValue;
            int minAxis = -1;

            for (i = 0; i < numAxes; ++i)
            {
                // If we can't normalise the axis, skip it
                float l2 = axes[i].LengthSquared();
                if (l2 < JiggleMath.Epsilon)
                    continue;

                // Normalise the separation axis and the depth
                float invl = 1.0f / (float)System.Math.Sqrt(l2);
                axes[i] *= invl;
                overlapDepths[i] *= invl;

                // If this axis is the minimum, select it
                if (overlapDepths[i] < minDepth)
                {
                    minDepth = overlapDepths[i];
                    minAxis = i;
                }
            }

            if (minAxis == -1)
                return false;

            // Make sure the axis is facing towards the 0th box.
            // if not, invert it
            Vector3 D = newBox.GetCentre() - tri.Centre;
            Vector3 N = axes[minAxis];
            float depth = overlapDepths[minAxis];

            if (Vector3.Dot(D, N) < 0.0f)
               N *= -1;

            Vector3 boxOldPos = (info.Skin0.Owner != null) ? info.Skin0.Owner.OldPosition : Vector3.Zero;
            Vector3 boxNewPos = (info.Skin0.Owner != null) ? info.Skin0.Owner.Position : Vector3.Zero;
            Vector3 meshPos = (info.Skin1.Owner != null) ? info.Skin1.Owner.OldPosition : Vector3.Zero;

            List<Vector3> pts = new List<Vector3>();
            //pts.Clear();

            const float combinationDist = 0.05f;
            GetBoxTriangleIntersectionPoints(pts, newBox, tri, depth + combinationDist);

            // adjust the depth
            #region REFERENCE: Vector3 delta = boxNewPos - boxOldPos;
            Vector3 delta;
            Vector3.Subtract(ref boxNewPos, ref boxOldPos, out delta);
            #endregion

            #region REFERENCE: float oldDepth = depth + Vector3.Dot(delta, N);
            float oldDepth;
            Vector3.Dot(ref delta, ref N, out oldDepth);
            oldDepth += depth;
            #endregion

            unsafe
            {
                // report collisions
                int numPts = pts.Count;
            #if USE_STACKALLOC
                SmallCollPointInfo* collPts = stackalloc SmallCollPointInfo[MaxLocalStackSCPI];
            #else
                SmallCollPointInfo[] collPtArray = SCPIStackAlloc();
                fixed (SmallCollPointInfo* collPts = collPtArray)
            #endif
                {
                    if (numPts > 0)
                    {
                        if (numPts >= MaxLocalStackSCPI)
                        {
                            numPts = MaxLocalStackSCPI - 1;
                        }

                        // adjust positions
                        for (i = 0; i < numPts; ++i)
                        {
                            collPts[i] = new SmallCollPointInfo(pts[i] - boxNewPos, pts[i] - meshPos, oldDepth);
                        }

                        collisionFunctor.CollisionNotify(ref info, ref N, collPts, numPts);
            #if !USE_STACKALLOC
                        FreeStackAlloc(collPtArray);
            #endif
                        return true;
                    }
                    else
                    {
            #if !USE_STACKALLOC
                        FreeStackAlloc(collPtArray);
            #endif
                        return false;
                    }
                }

            }
        }
Exemplo n.º 9
0
        public static bool SweptSphereTriangleIntersection(out Vector3 pt, out Vector3 N, out float depth,
            BoundingSphere oldSphere, BoundingSphere newSphere, Triangle triangle,
            float oldCentreDistToPlane, float newCentreDistToPlane,
            EdgesToTest edgesToTest, CornersToTest cornersToTest)
        {
            int i;
            Microsoft.Xna.Framework.Plane trianglePlane = triangle.Plane;
            N = Vector3.Zero;

            // Check against plane
            if (!SweptSpherePlaneIntersection(out pt,out depth, oldSphere, newSphere, trianglePlane.Normal, oldCentreDistToPlane, newCentreDistToPlane))
                return false;

            Vector3 v0 = triangle.GetPoint(0);
            Vector3 v1 = triangle.GetPoint(1);
            Vector3 v2 = triangle.GetPoint(2);

            Vector3 e0 = v1 - v0;
            Vector3 e1 = v2 - v1;
            Vector3 e2 = v0 - v2;

            // If the point is inside the triangle, this is a hit
            bool allInside = true;
            Vector3 outDir0 = Vector3.Cross(e0, trianglePlane.Normal);
            if (Vector3.Dot(pt - v0, outDir0) > 0.0f)
            {
                allInside = false;
            }
            Vector3 outDir1 = Vector3.Cross(e1, trianglePlane.Normal);
            if (Vector3.Dot(pt - v1, outDir1) > 0.0f)
            {
                allInside = false;
            }
            Vector3 outDir2 = Vector3.Cross(e2, trianglePlane.Normal);
            if (Vector3.Dot(pt - v2, outDir2) > 0.0f)
            {
                allInside = false;
            }

            // Quick result?
            if (allInside)
            {
                N = trianglePlane.Normal;
                return true;
            }

            // Now check against the edges
            float bestT = float.MaxValue;
            Vector3 Ks = newSphere.Center - oldSphere.Center;
            float kss = Vector3.Dot(Ks, Ks);
            float radius = newSphere.Radius;
            float radiusSq = radius * radius;
            for (i = 0; i < 3; ++i)
            {
                int mask = 1 << i;
                if (!((mask !=0) & ((int)edgesToTest != 0))) // TODO: CHECK THIS
                    continue;
                Vector3 Ke;
                Vector3 vp;

                switch (i)
                {
                    case 0:
                        Ke = e0;
                        vp = v0;
                        break;
                    case 1:
                        Ke = e1;
                        vp = v1;
                        break;
                    case 2:
                    default:
                        Ke = e2;
                        vp = v2;
                        break;

                }
                Vector3 Kg = vp - oldSphere.Center;

                float kee = Vector3.Dot(Ke, Ke);
                if (System.Math.Abs(kee) < JiggleMath.Epsilon)
                    continue;
                float kes = Vector3.Dot(Ke, Ks);
                float kgs = Vector3.Dot(Kg, Ks);
                float keg = Vector3.Dot(Ke, Kg);
                float kgg = Vector3.Dot(Kg, Kg);

                // a * t^2 + b * t + c = 0
                float a = kee * kss - (kes * kes);
                if (System.Math.Abs(a) < JiggleMath.Epsilon)
                    continue;
                float b = 2.0f * (keg * kes - kee * kgs);
                float c = kee * (kgg - radiusSq) - keg * keg;

                float blah = b*b - 4.0f * a * c;
                if (blah < 0.0f)
                    continue;

                // solve for t - take minimum
                float t = (-b - (float)System.Math.Sqrt(blah)) / (2.0f * a);

                if (t < 0.0f || t > 1.0f)
                    continue;

                if (t > bestT)
                    continue;

                // now check where it hit on the edge
                Vector3 Ct = oldSphere.Center + t * Ks;
                float d = Vector3.Dot((Ct - vp), Ke) / kee;

                if (d < 0.0f || d > 1.0f)
                    continue;

                // wahay - got hit. Already checked that t < bestT
                bestT = t;

                pt = vp + d * Ke;
                N = (Ct - pt);// .GetNormalisedSafe();
                JiggleMath.NormalizeSafe(ref N);
                // depth is already calculated
            }
            if (bestT <= 1.0f)
                return true;

            // check the corners
            bestT = float.MaxValue;
            for (i = 0; i < 3; ++i)
            {
                int mask = 1 << i;
                if (!((mask != 0) & (cornersToTest != 0))) // CHECK THIS
                    continue;
                Vector3 vp;

                switch (i)
                {
                    case 0:
                        vp = v0;
                        break;
                    case 1:
                        vp = v1;
                        break;
                    case 2:
                    default:
                        vp = v2;
                        break;

                }
                Vector3 Kg = vp - oldSphere.Center;
                float kgs = Vector3.Dot(Kg, Ks);
                float kgg = Vector3.Dot(Kg, Kg);
                float a = kss;
                if (System.Math.Abs(a) < JiggleMath.Epsilon)
                    continue;
                float b = -2.0f * kgs;
                float c = kgg - radiusSq;

                float blah = (b * b) - 4.0f * a * c;
                if (blah < 0.0f)
                    continue;

                // solve for t - take minimum
                float t = (-b - (float) System.Math.Sqrt(blah)) / (2.0f * a);

                if (t < 0.0f || t > 1.0f)
                    continue;

                if (t > bestT)
                    continue;

                bestT = t;

                Vector3 Ct = oldSphere.Center + t * Ks;
                N = (Ct - vp);//.GetNormalisedSafe();
                JiggleMath.NormalizeSafe(ref N);
            }
            if (bestT <= 1.0f)
                return true;

            return false;
        }
Exemplo n.º 10
0
        public static bool SweptSphereTriangleIntersection(out Vector3 pt, out Vector3 N, out float depth, BoundingSphere oldSphere, BoundingSphere newSphere, Triangle triangle, float oldCentreDistToPlane, float newCentreDistToPlane, EdgesToTest edgesToTest, CornersToTest cornersToTest)
        {
            int i;
            var trianglePlane = triangle.Plane;

            N = Vector3.Zero;


            if (!SweptSpherePlaneIntersection(out pt, out depth, oldSphere, newSphere, trianglePlane.Normal, oldCentreDistToPlane, newCentreDistToPlane))
            {
                return(false);
            }

            var v0 = triangle.GetPoint(0);
            var v1 = triangle.GetPoint(1);
            var v2 = triangle.GetPoint(2);

            var e0 = v1 - v0;
            var e1 = v2 - v1;
            var e2 = v0 - v2;


            var allInside = true;
            var outDir0   = Vector3.Cross(e0, trianglePlane.Normal);

            if (Vector3.Dot(pt - v0, outDir0) > 0.0f)
            {
                allInside = false;
            }
            var outDir1 = Vector3.Cross(e1, trianglePlane.Normal);

            if (Vector3.Dot(pt - v1, outDir1) > 0.0f)
            {
                allInside = false;
            }
            var outDir2 = Vector3.Cross(e2, trianglePlane.Normal);

            if (Vector3.Dot(pt - v2, outDir2) > 0.0f)
            {
                allInside = false;
            }


            if (allInside)
            {
                N = trianglePlane.Normal;
                return(true);
            }


            var bestT    = float.MaxValue;
            var Ks       = newSphere.Center - oldSphere.Center;
            var kss      = Vector3.Dot(Ks, Ks);
            var radius   = newSphere.Radius;
            var radiusSq = radius * radius;

            for (i = 0; i < 3; ++i)
            {
                var mask = 1 << i;
                if (!((mask != 0) & ((int)edgesToTest != 0)))
                {
                    continue;
                }
                Vector3 Ke;
                Vector3 vp;

                switch (i)
                {
                case 0:
                    Ke = e0;
                    vp = v0;
                    break;

                case 1:
                    Ke = e1;
                    vp = v1;
                    break;

                case 2:
                default:
                    Ke = e2;
                    vp = v2;
                    break;
                }

                var Kg = vp - oldSphere.Center;

                var kee = Vector3.Dot(Ke, Ke);
                if (System.Math.Abs(kee) < JiggleMath.Epsilon)
                {
                    continue;
                }
                var kes = Vector3.Dot(Ke, Ks);
                var kgs = Vector3.Dot(Kg, Ks);
                var keg = Vector3.Dot(Ke, Kg);
                var kgg = Vector3.Dot(Kg, Kg);


                var a = kee * kss - kes * kes;
                if (System.Math.Abs(a) < JiggleMath.Epsilon)
                {
                    continue;
                }
                var b = 2.0f * (keg * kes - kee * kgs);
                var c = kee * (kgg - radiusSq) - keg * keg;

                var blah = b * b - 4.0f * a * c;
                if (blah < 0.0f)
                {
                    continue;
                }


                var t = (-b - (float)System.Math.Sqrt(blah)) / (2.0f * a);

                if (t < 0.0f || t > 1.0f)
                {
                    continue;
                }

                if (t > bestT)
                {
                    continue;
                }


                var Ct = oldSphere.Center + t * Ks;
                var d  = Vector3.Dot(Ct - vp, Ke) / kee;

                if (d < 0.0f || d > 1.0f)
                {
                    continue;
                }


                bestT = t;

                pt = vp + d * Ke;
                N  = Ct - pt;
                JiggleMath.NormalizeSafe(ref N);
            }

            if (bestT <= 1.0f)
            {
                return(true);
            }


            bestT = float.MaxValue;
            for (i = 0; i < 3; ++i)
            {
                var mask = 1 << i;
                if (!((mask != 0) & (cornersToTest != 0)))
                {
                    continue;
                }
                Vector3 vp;

                switch (i)
                {
                case 0:
                    vp = v0;
                    break;

                case 1:
                    vp = v1;
                    break;

                case 2:
                default:
                    vp = v2;
                    break;
                }

                var Kg  = vp - oldSphere.Center;
                var kgs = Vector3.Dot(Kg, Ks);
                var kgg = Vector3.Dot(Kg, Kg);
                var a   = kss;
                if (System.Math.Abs(a) < JiggleMath.Epsilon)
                {
                    continue;
                }
                var b = -2.0f * kgs;
                var c = kgg - radiusSq;

                var blah = b * b - 4.0f * a * c;
                if (blah < 0.0f)
                {
                    continue;
                }


                var t = (-b - (float)System.Math.Sqrt(blah)) / (2.0f * a);

                if (t < 0.0f || t > 1.0f)
                {
                    continue;
                }

                if (t > bestT)
                {
                    continue;
                }

                bestT = t;

                var Ct = oldSphere.Center + t * Ks;
                N = Ct - vp;
                JiggleMath.NormalizeSafe(ref N);
            }

            if (bestT <= 1.0f)
            {
                return(true);
            }

            return(false);
        }