/// <summary>
/// Gets the polyhedron feature that is the most extreme, or furthest along, the specified direction.
/// </summary>
/// <remarks>
/// If two vertices are equally far along the given direction, then an edge feature is returned. If more
/// than two vertices are equally far, then the extreme feature is a face.
/// </remarks>
/// <param name="d">The normalized direction vector along which to search for an extreme feature.</param>
/// <returns>Returns the extreme feature that is furthest along the specified direction.</returns>
public PolyhedronFeature ExtremeFeature(ref Vector3 d)
{
PolyhedronFeature e = ExtremeVertex(ref d);
Vector3 v;
int vIndex = e.Index;
for (int i = 0; i < _compiled.Neighbors[vIndex].Length; i++)
{
float x;
int newIndex = _compiled.Neighbors[vIndex][i];
v = _world[newIndex];
Vector3.Dot(ref d, ref v, out x);
if (FloatHelper.Equals(x, e.X))
{
if (e.Type == PolyhedronFeatureType.Vertex)
{
for (int j = 0; j < _compiled.Edges.Length; j++)
{
if ((_compiled.Edges[j][0] == vIndex && _compiled.Edges[j][1] == newIndex) ||
(_compiled.Edges[j][0] == newIndex && _compiled.Edges[j][1] == vIndex))
{
e.Type = PolyhedronFeatureType.Edge;
e.Index = j;
break;
}
}
}
else if (e.Type == PolyhedronFeatureType.Edge)
{
for (int j = 0; j < _compiled.Faces.Length; j++)
{
int count = 0;
for (int k = 0; k < _compiled.Faces[j].Length; k++)
{
if (_compiled.Faces[j][k] == _compiled.Edges[e.Index][0] ||
_compiled.Faces[j][k] == _compiled.Edges[e.Index][1] ||
_compiled.Faces[j][k] == newIndex)
{
count++;
}
if (count > 2)
{
break;
}
}
if (count > 2)
{
e.Type = PolyhedronFeatureType.Face;
e.Index = j;
break;
}
}
}
else
{
break;
}
}
}
return(e);
}
/// <summary>
/// Gets the polyhedron feature that is the most extreme, or furthest along, the specified direction and for which
/// all vertices are at least as extreme as the specified depth.
/// </summary>
/// <remarks>
/// If two vertices are more extreme than the specified depth, then an edge is returned. If more than two vertices are
/// more extreme than the specified depth, then a face is returned. The result will always include the vertex of maximum
/// extremity.
/// </remarks>
/// <param name="d">The normalized direction vector along which to search for an extreme feature.</param>
/// <param name="depth">All vertices that make up the returned feature must be at least this "deep" along the
/// given direction.</param>
/// <returns>Returns the extreme feature.</returns>
public PolyhedronFeature ExtremeFeature(ref Vector3 d, float depth)
{
PolyhedronFeature e = ExtremeVertex(ref d);
Vector3 v;
if (depth - e.X >= Constants.Epsilon)
{
e.Type = PolyhedronFeatureType.None;
return(e);
}
int vIndex = e.Index;
for (int i = 0; i < _compiled.Neighbors[vIndex].Length; i++)
{
float x;
int newIndex = _compiled.Neighbors[vIndex][i];
World(newIndex, out v);
Vector3.Dot(ref d, ref v, out x);
if (x >= depth)
{
if (e.Type == PolyhedronFeatureType.Vertex)
{
for (int j = 0; j < _compiled.Edges.Length; j++)
{
if ((_compiled.Edges[j][0] == vIndex && _compiled.Edges[j][1] == newIndex) ||
(_compiled.Edges[j][0] == newIndex && _compiled.Edges[j][1] == vIndex))
{
e.Type = PolyhedronFeatureType.Edge;
e.Index = j;
break;
}
}
}
else if (e.Type == PolyhedronFeatureType.Edge)
{
for (int j = 0; j < _compiled.Faces.Length; j++)
{
int count = 0;
for (int k = 0; k < _compiled.Faces[j].Length; k++)
{
if (_compiled.Faces[j][k] == _compiled.Edges[e.Index][0] ||
_compiled.Faces[j][k] == _compiled.Edges[e.Index][1] ||
_compiled.Faces[j][k] == newIndex)
{
count++;
}
if (count > 2)
{
break;
}
}
if (count > 2)
{
e.Type = PolyhedronFeatureType.Face;
e.Index = j;
break;
}
}
}
else
{
continue;
}
}
}
return(e);
}
