// 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
private int GetBoxTriangleIntersectionPoints(List <MyCP> pts, MyBox box, MyColDetVoxelTriangle triangle, float combinationDistance)
{
// first intersect each edge of the box with the triangleVertexes
MyBox.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)
{
MyBox.Edge edge = edges[iEdge];
MySegment seg = new MySegment(boxPts[(int)edge.Ind0], boxPts[(int)edge.Ind1] - boxPts[(int)edge.Ind0]);
if (this.SegmentTriangleIntersection(out tS, out tv1, out tv2, seg, triangle))
{
float depthA = Vector3.Dot(boxPts[(int)edge.Ind0] - seg.GetPoint(tS), triangle.Normal);
float depthB = Vector3.Dot(boxPts[(int)edge.Ind1] - seg.GetPoint(tS), triangle.Normal);
AddPoint(pts, seg.GetPoint(tS), triangle.Normal, depthA < depthB ? depthA : depthB, combinationDistance * combinationDistance);
}
}
Vector3 pos, n;
// now each edge of the triangleVertexes with the box
for (iEdge = 0; iEdge < 3; ++iEdge)
{
Vector3 pt0 = triangle.GetPoint(iEdge);
Vector3 pt1 = triangle.GetPoint((iEdge + 1) % 3);
MySegment s1 = new MySegment(pt0, pt1 - pt0);
MySegment s2 = new MySegment(pt1, pt0 - pt1);
if (box.SegmentIntersect(out tS, out pos, out n, s1))
{
float depthA = Vector3.Dot(pt0 - pos, triangle.Normal);
float depthB = Vector3.Dot(pt1 - pos, triangle.Normal);
AddPoint(pts, pos, triangle.Normal, depthA < depthB ? depthA : depthB, combinationDistance * combinationDistance);
}
if (box.SegmentIntersect(out tS, out pos, out n, s2))
{
float depthA = Vector3.Dot(pt0 - pos, triangle.Normal);
float depthB = Vector3.Dot(pt1 - pos, triangle.Normal);
AddPoint(pts, pos, triangle.Normal, depthA < depthB ? depthA : depthB, combinationDistance * combinationDistance);
}
}
return(pts.Count);
}
public bool SegmentIntersect(out float fracOut, out Vector3 posOut, out Vector3 normalOut, MySegment seg)
{
fracOut = float.MaxValue;
posOut = normalOut = Vector3.Zero;
// algo taken from p674 of realting rendering
// needs debugging
float min = float.MinValue;
float max = float.MaxValue;
Vector3 p = GetCentre() - seg.Origin;
Vector3 h;
h.X = m_sideLengths.X * 0.5f;
h.Y = m_sideLengths.Y * 0.5f;
h.Z = m_sideLengths.Z * 0.5f;
int dirMax = 0;
int dirMin = 0;
int dir = 0;
//Vector3[] matrixVec = new Vector3[3];
MyVector3Array3 matrixVec = new MyVector3Array3();
matrixVec[0] = Transform.Orientation.Right;
matrixVec[1] = Transform.Orientation.Up;
matrixVec[2] = Transform.Orientation.Backward;
//float[] vectorFloat = new float[3];
MyFloatArray3 vectorFloat = new MyFloatArray3();
vectorFloat[0] = h.X;
vectorFloat[1] = h.Y;
vectorFloat[2] = h.Z;
for (dir = 0; dir < 3; dir++)
{
float e = Vector3.Dot(matrixVec[dir], p);
float f = Vector3.Dot(matrixVec[dir], seg.Delta);
if (System.Math.Abs(f) > MyPhysicsConfig.CollisionEpsilon)
{
float t1 = (e + vectorFloat[dir]) / f;
float t2 = (e - vectorFloat[dir]) / f;
if (t1 > t2) { float tmp = t1; t1 = t2; t2 = tmp; }
if (t1 > min)
{
min = t1;
dirMin = dir;
}
if (t2 < max)
{
max = t2;
dirMax = dir;
}
if (min > max)
return false;
if (max < 0.0f)
return false;
}
else if ((-e - vectorFloat[dir] > 0.0f) ||
(-e + vectorFloat[dir] < 0.0f))
{
return false;
}
}
if (min > 0.0f)
{
dir = dirMin;
fracOut = min;
}
else
{
dir = dirMax;
fracOut = max;
}
fracOut = MathHelper.Clamp(fracOut, 0.0f, 1.0f);
posOut = seg.GetPoint(fracOut);
if (Vector3.Dot(matrixVec[dir], seg.Delta) > 0.0f)
normalOut = -matrixVec[dir];
else
normalOut = matrixVec[dir];
return true;
}
public bool SegmentIntersect(out float fracOut, out Vector3 posOut, out Vector3 normalOut, MySegment seg)
{
fracOut = float.MaxValue;
posOut = normalOut = Vector3.Zero;
// algo taken from p674 of realting rendering
// needs debugging
float min = float.MinValue;
float max = float.MaxValue;
Vector3 p = GetCentre() - seg.Origin;
Vector3 h;
h.X = m_sideLengths.X * 0.5f;
h.Y = m_sideLengths.Y * 0.5f;
h.Z = m_sideLengths.Z * 0.5f;
int dirMax = 0;
int dirMin = 0;
int dir = 0;
//Vector3[] matrixVec = new Vector3[3];
MyVector3Array3 matrixVec = new MyVector3Array3();
matrixVec[0] = Transform.Orientation.Right;
matrixVec[1] = Transform.Orientation.Up;
matrixVec[2] = Transform.Orientation.Backward;
//float[] vectorFloat = new float[3];
MyFloatArray3 vectorFloat = new MyFloatArray3();
vectorFloat[0] = h.X;
vectorFloat[1] = h.Y;
vectorFloat[2] = h.Z;
for (dir = 0; dir < 3; dir++)
{
float e = Vector3.Dot(matrixVec[dir], p);
float f = Vector3.Dot(matrixVec[dir], seg.Delta);
if (System.Math.Abs(f) > MyPhysicsConfig.CollisionEpsilon)
{
float t1 = (e + vectorFloat[dir]) / f;
float t2 = (e - vectorFloat[dir]) / f;
if (t1 > t2)
{
float tmp = t1; t1 = t2; t2 = tmp;
}
if (t1 > min)
{
min = t1;
dirMin = dir;
}
if (t2 < max)
{
max = t2;
dirMax = dir;
}
if (min > max)
{
return(false);
}
if (max < 0.0f)
{
return(false);
}
}
else if ((-e - vectorFloat[dir] > 0.0f) ||
(-e + vectorFloat[dir] < 0.0f))
{
return(false);
}
}
if (min > 0.0f)
{
dir = dirMin;
fracOut = min;
}
else
{
dir = dirMax;
fracOut = max;
}
fracOut = MathHelper.Clamp(fracOut, 0.0f, 1.0f);
posOut = seg.GetPoint(fracOut);
if (Vector3.Dot(matrixVec[dir], seg.Delta) > 0.0f)
{
normalOut = -matrixVec[dir];
}
else
{
normalOut = matrixVec[dir];
}
return(true);
}
// 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
private int GetBoxTriangleIntersectionPoints(List<MyCP> pts, MyBox box, MyColDetVoxelTriangle triangle, float combinationDistance)
{
// first intersect each edge of the box with the triangleVertexes
MyBox.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)
{
MyBox.Edge edge = edges[iEdge];
MySegment seg = new MySegment(boxPts[(int)edge.Ind0], boxPts[(int)edge.Ind1] - boxPts[(int)edge.Ind0]);
if (this.SegmentTriangleIntersection(out tS, out tv1, out tv2, seg, triangle))
{
float depthA = Vector3.Dot(boxPts[(int)edge.Ind0] - seg.GetPoint(tS), triangle.Normal);
float depthB = Vector3.Dot(boxPts[(int)edge.Ind1] - seg.GetPoint(tS), triangle.Normal);
AddPoint(pts, seg.GetPoint(tS),triangle.Normal, depthA < depthB ? depthA : depthB , combinationDistance * combinationDistance);
}
}
Vector3 pos, n;
// now each edge of the triangleVertexes with the box
for (iEdge = 0; iEdge < 3; ++iEdge)
{
Vector3 pt0 = triangle.GetPoint(iEdge);
Vector3 pt1 = triangle.GetPoint((iEdge + 1) % 3);
MySegment s1 = new MySegment(pt0, pt1 - pt0);
MySegment s2 = new MySegment(pt1, pt0 - pt1);
if (box.SegmentIntersect(out tS, out pos, out n, s1))
{
float depthA = Vector3.Dot(pt0 - pos, triangle.Normal);
float depthB = Vector3.Dot(pt1 - pos, triangle.Normal);
AddPoint(pts, pos, triangle.Normal, depthA < depthB ? depthA : depthB, combinationDistance * combinationDistance);
}
if (box.SegmentIntersect(out tS, out pos, out n, s2))
{
float depthA = Vector3.Dot(pt0 - pos, triangle.Normal);
float depthB = Vector3.Dot(pt1 - pos, triangle.Normal);
AddPoint(pts, pos, triangle.Normal, depthA < depthB ? depthA : depthB, combinationDistance * combinationDistance);
}
}
return pts.Count;
}