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Initialize the creation of a general multipatch.
[Visual Basic .NET] Public Sub Init ( _ ByVal PointCount As Integer, _ ByVal partCount As Integer, _ ByVal hasMs As Boolean, _ ByVal hasIDs As Boolean, _ ByVal hasNormals As Boolean, _ ByVal TexturePointCount As Integer, _ ByVal pGeometryMaterialList As IGeometryMaterialList _ )
[C#] public void Init ( int PointCount, int partCount, bool hasMs, bool hasIDs, bool hasNormals, int TexturePointCount, IGeometryMaterialList pGeometryMaterialList );
[C++]
HRESULT Init(
long PointCount,
long partCount,
VARIANT_BOOL hasMs,
VARIANT_BOOL hasIDs,
VARIANT_BOOL hasNormals,
long TexturePointCount,
IGeometryMaterialList* pGeometryMaterialList
);
[C++] Parameters PointCount [in]
PointCount is a parameter of type long partCount [in]
partCount is a parameter of type long hasMs [in]
hasMs is a parameter of type bool hasIDs [in]
hasIDs is a parameter of type bool hasNormals [in]
hasNormals is a parameter of type bool TexturePointCount [in]
TexturePointCount is a parameter of type long pGeometryMaterialList [in]
pGeometryMaterialList is a parameter of type IGeometryMaterialList*
For IGeneralMultipatchCreator interface, part and patch are used interchangeably. So are point and vertex.
When initialize a multipatch, pay close attention to the number of points and texture points. The number of points represents the total point count, whereas the number of texture points represents only those that are involved in deciding texture coordinates. Therefore, the number of points should be equal or greater than the number of texture points.
For a polygonal part, the first and the last point should be at the same coordinate so that the polygon would close. So a square or rectangle polygon should have five points. This applies to rings in a multipatch. Similarly, a triangle fan's first non-center point should repeat itself in closing. Therefore a sqaure-based pyramid should have six points, rather than five.
For the ArcGIS 9.0 newly introduced multipatch part triangles, however, one triangle does not need to have an extra point to close. This means that a triangle has only three points.