NAME
	  DtFaceGetNormalIndex - Get the list of polygonal normal
	  indices for all the polygons in the given shape and group
	  IDs.


     SYNOPSIS
	  #include <Dt.h>


	  int  DtFaceGetNormalIndexByShape( int	shapeID, int groupID, int *count, long **indices);
	  int  DtFaceGetNormalIndexByGroup( int	shapeID, int groupID, int *count, long **indices);


     DESCRIPTION
	  DtFaceGetNormalIndex() returns a list	of polygon normal
	  indices via the pointer to the variable indices given	the
	  shape	number,	shapeID, and group number, groupID. The	total
	  number of normal indices into	the normal list	(the length of
	  the indices array) is	returned via the pointer to the	count
	  parameter.  Each polygon in the indices array	is separated
	  by an	index DtEND_OF_FACE (-1). The number of	indices	return
	  via the pointer to count includes the	DtEND_OF_FACE
	  separators.  For example, if the first group (groupID	= 0)
	  of the first shape (shapeID =	0) has two triangles, the
	  format of the	normal index array will	be:

	       1 2 3 -1	4 5 6 -1

	  were indices 1, 2, and 3 are for polygon 0 and 4, 5, and 6
	  are for polygon 1.  The parameter count will be set to 8.

	  If no	normals	exist the indices array	will be	set to NULL.
	  The indices array is an internal buffer.  Do not free	or
	  modify the index array.

	  DtFaceGetNormalIndexByShape()	returns	an array of indices
	  relative to the vertex normal	list for the shape (as
	  returned by DtShapeGetNormals(3W)).
	  DtFaceGetNormalIndexByGroup()	returns	an array of indices
	  relative to the vertex normal	list for the group (as
	  returned by DtGroupGetNormals(3W)).



     DIAGNOSTICS
	  DtFaceGetNormalIndex() returns one on	success	and zero on
	  failure.


     SEE ALSO
	  DtFaceGetNormalIndexByGroup(3W)
	  DtGroupGetNormals(3W)
	  DtIndexCount(3W)
	  DtShapeGetNormals(3W)


     FILES
	  Link with -lDtOMio