public static Mesh Compute(Ellipsoid ellipsoid, int numberOfPartitions, CubeMapEllipsoidVertexAttributes vertexAttributes)
{
if (numberOfPartitions < 0)
{
throw new ArgumentOutOfRangeException("numberOfPartitions");
}
if ((vertexAttributes & CubeMapEllipsoidVertexAttributes.Position) != CubeMapEllipsoidVertexAttributes.Position)
{
throw new ArgumentException("Positions must be provided.", "vertexAttributes");
}
Mesh mesh = new Mesh();
mesh.PrimitiveType = PrimitiveType.Triangles;
mesh.FrontFaceWindingOrder = WindingOrder.Counterclockwise;
int numberOfVertices = NumberOfVertices(numberOfPartitions);
VertexAttributeDoubleVector3 positionsAttribute = new VertexAttributeDoubleVector3("position", numberOfVertices);
mesh.Attributes.Add(positionsAttribute);
IndicesUnsignedInt indices = new IndicesUnsignedInt(3 * NumberOfTriangles(numberOfPartitions));
mesh.Indices = indices;
CubeMapMesh CubeMapMesh = new CubeMapMesh();
CubeMapMesh.Ellipsoid = ellipsoid;
CubeMapMesh.NumberOfPartitions = numberOfPartitions;
CubeMapMesh.Positions = positionsAttribute.Values;
CubeMapMesh.Indices = indices;
if ((vertexAttributes & CubeMapEllipsoidVertexAttributes.Normal) == CubeMapEllipsoidVertexAttributes.Normal)
{
VertexAttributeHalfFloatVector3 normalsAttribute = new VertexAttributeHalfFloatVector3("normal", numberOfVertices);
mesh.Attributes.Add(normalsAttribute);
CubeMapMesh.Normals = normalsAttribute.Values;
}
if ((vertexAttributes & CubeMapEllipsoidVertexAttributes.TextureCoordinate) == CubeMapEllipsoidVertexAttributes.TextureCoordinate)
{
VertexAttributeHalfFloatVector2 textureCoordinateAttribute = new VertexAttributeHalfFloatVector2("textureCoordinate", numberOfVertices);
mesh.Attributes.Add(textureCoordinateAttribute);
CubeMapMesh.TextureCoordinate = textureCoordinateAttribute.Values;
}
//
// Initial cube. In the plane, z = -1:
//
// +y
// |
// Q2 * p3 Q1
// / | \
// p0 *--+--* p2 +x
// \ | /
// Q3 * p1 Q4
// |
//
// Similarly, p4 to p7 are in the plane z = 1.
//
CubeMapMesh.Positions.Add(new Vector3D(-1, 0, -1));
CubeMapMesh.Positions.Add(new Vector3D(0, -1, -1));
CubeMapMesh.Positions.Add(new Vector3D(1, 0, -1));
CubeMapMesh.Positions.Add(new Vector3D(0, 1, -1));
CubeMapMesh.Positions.Add(new Vector3D(-1, 0, 1));
CubeMapMesh.Positions.Add(new Vector3D(0, -1, 1));
CubeMapMesh.Positions.Add(new Vector3D(1, 0, 1));
CubeMapMesh.Positions.Add(new Vector3D(0, 1, 1));
//
// Edges
//
// 0 -> 1, 1 -> 2, 2 -> 3, 3 -> 0. Plane z = -1
// 4 -> 5, 5 -> 6, 6 -> 7, 7 -> 4. Plane z = 1
// 0 -> 4, 1 -> 5, 2 -> 6, 3 -> 7. From plane z = -1 to plane z - 1
//
int[] edge0to1 = AddEdgePositions(0, 1, CubeMapMesh);
int[] edge1to2 = AddEdgePositions(1, 2, CubeMapMesh);
int[] edge2to3 = AddEdgePositions(2, 3, CubeMapMesh);
int[] edge3to0 = AddEdgePositions(3, 0, CubeMapMesh);
int[] edge4to5 = AddEdgePositions(4, 5, CubeMapMesh);
int[] edge5to6 = AddEdgePositions(5, 6, CubeMapMesh);
int[] edge6to7 = AddEdgePositions(6, 7, CubeMapMesh);
int[] edge7to4 = AddEdgePositions(7, 4, CubeMapMesh);
int[] edge0to4 = AddEdgePositions(0, 4, CubeMapMesh);
int[] edge1to5 = AddEdgePositions(1, 5, CubeMapMesh);
int[] edge2to6 = AddEdgePositions(2, 6, CubeMapMesh);
int[] edge3to7 = AddEdgePositions(3, 7, CubeMapMesh);
AddFaceTriangles(edge0to4, edge0to1, edge1to5, edge4to5, CubeMapMesh); // Q3 Face
AddFaceTriangles(edge1to5, edge1to2, edge2to6, edge5to6, CubeMapMesh); // Q4 Face
AddFaceTriangles(edge2to6, edge2to3, edge3to7, edge6to7, CubeMapMesh); // Q1 Face
AddFaceTriangles(edge3to7, edge3to0, edge0to4, edge7to4, CubeMapMesh); // Q2 Face
AddFaceTriangles(ReversedArray(edge7to4), edge4to5, edge5to6, ReversedArray(edge6to7), CubeMapMesh); // Plane z = 1
AddFaceTriangles(edge1to2, ReversedArray(edge0to1), ReversedArray(edge3to0), edge2to3, CubeMapMesh); // Plane z = -1
CubeToEllipsoid(CubeMapMesh);
return mesh;
}
public static Mesh Compute(Ellipsoid ellipsoid, int numberOfPartitions, CubeMapEllipsoidVertexAttributes vertexAttributes)
{
if (numberOfPartitions < 0)
{
throw new ArgumentOutOfRangeException("numberOfPartitions");
}
if ((vertexAttributes & CubeMapEllipsoidVertexAttributes.Position) != CubeMapEllipsoidVertexAttributes.Position)
{
throw new ArgumentException("Positions must be provided.", "vertexAttributes");
}
Mesh mesh = new Mesh();
mesh.PrimitiveType = PrimitiveType.Triangles;
mesh.FrontFaceWindingOrder = WindingOrder.Counterclockwise;
int numberOfVertices = NumberOfVertices(numberOfPartitions);
VertexAttributeDoubleVector3 positionsAttribute = new VertexAttributeDoubleVector3("position", numberOfVertices);
mesh.Attributes.Add(positionsAttribute);
IndicesUnsignedInt indices = new IndicesUnsignedInt(3 * NumberOfTriangles(numberOfPartitions));
mesh.Indices = indices;
CubeMapMesh CubeMapMesh = new CubeMapMesh();
CubeMapMesh.Ellipsoid = ellipsoid;
CubeMapMesh.NumberOfPartitions = numberOfPartitions;
CubeMapMesh.Positions = positionsAttribute.Values;
CubeMapMesh.Indices = indices;
if ((vertexAttributes & CubeMapEllipsoidVertexAttributes.Normal) == CubeMapEllipsoidVertexAttributes.Normal)
{
VertexAttributeHalfFloatVector3 normalsAttribute = new VertexAttributeHalfFloatVector3("normal", numberOfVertices);
mesh.Attributes.Add(normalsAttribute);
CubeMapMesh.Normals = normalsAttribute.Values;
}
if ((vertexAttributes & CubeMapEllipsoidVertexAttributes.TextureCoordinate) == CubeMapEllipsoidVertexAttributes.TextureCoordinate)
{
VertexAttributeHalfFloatVector2 textureCoordinateAttribute = new VertexAttributeHalfFloatVector2("textureCoordinate", numberOfVertices);
mesh.Attributes.Add(textureCoordinateAttribute);
CubeMapMesh.TextureCoordinate = textureCoordinateAttribute.Values;
}
//
// Initial cube. In the plane, z = -1:
//
// +y
// |
// Q2 * p3 Q1
// / | \
// p0 *--+--* p2 +x
// \ | /
// Q3 * p1 Q4
// |
//
// Similarly, p4 to p7 are in the plane z = 1.
//
CubeMapMesh.Positions.Add(new Vector3D(-1, 0, -1));
CubeMapMesh.Positions.Add(new Vector3D(0, -1, -1));
CubeMapMesh.Positions.Add(new Vector3D(1, 0, -1));
CubeMapMesh.Positions.Add(new Vector3D(0, 1, -1));
CubeMapMesh.Positions.Add(new Vector3D(-1, 0, 1));
CubeMapMesh.Positions.Add(new Vector3D(0, -1, 1));
CubeMapMesh.Positions.Add(new Vector3D(1, 0, 1));
CubeMapMesh.Positions.Add(new Vector3D(0, 1, 1));
//
// Edges
//
// 0 -> 1, 1 -> 2, 2 -> 3, 3 -> 0. Plane z = -1
// 4 -> 5, 5 -> 6, 6 -> 7, 7 -> 4. Plane z = 1
// 0 -> 4, 1 -> 5, 2 -> 6, 3 -> 7. From plane z = -1 to plane z - 1
//
int[] edge0to1 = AddEdgePositions(0, 1, CubeMapMesh);
int[] edge1to2 = AddEdgePositions(1, 2, CubeMapMesh);
int[] edge2to3 = AddEdgePositions(2, 3, CubeMapMesh);
int[] edge3to0 = AddEdgePositions(3, 0, CubeMapMesh);
int[] edge4to5 = AddEdgePositions(4, 5, CubeMapMesh);
int[] edge5to6 = AddEdgePositions(5, 6, CubeMapMesh);
int[] edge6to7 = AddEdgePositions(6, 7, CubeMapMesh);
int[] edge7to4 = AddEdgePositions(7, 4, CubeMapMesh);
int[] edge0to4 = AddEdgePositions(0, 4, CubeMapMesh);
int[] edge1to5 = AddEdgePositions(1, 5, CubeMapMesh);
int[] edge2to6 = AddEdgePositions(2, 6, CubeMapMesh);
int[] edge3to7 = AddEdgePositions(3, 7, CubeMapMesh);
AddFaceTriangles(edge0to4, edge0to1, edge1to5, edge4to5, CubeMapMesh); // Q3 Face
AddFaceTriangles(edge1to5, edge1to2, edge2to6, edge5to6, CubeMapMesh); // Q4 Face
AddFaceTriangles(edge2to6, edge2to3, edge3to7, edge6to7, CubeMapMesh); // Q1 Face
AddFaceTriangles(edge3to7, edge3to0, edge0to4, edge7to4, CubeMapMesh); // Q2 Face
AddFaceTriangles(ReversedArray(edge7to4), edge4to5, edge5to6, ReversedArray(edge6to7), CubeMapMesh); // Plane z = 1
AddFaceTriangles(edge1to2, ReversedArray(edge0to1), ReversedArray(edge3to0), edge2to3, CubeMapMesh); // Plane z = -1
CubeToEllipsoid(CubeMapMesh);
return(mesh);
}
