TRIANGULAR_STRIP(3G)

NAME

triangular_strip − defines a series of triangular regions to be filled and/or edged.

SYNOPSIS

C Syntax:

void triangular_strip(fildes,clist,numverts,gnormals);
int fildes,numverts;
float clist[],gnormals[];

FORTRAN77 Syntax:

subroutine triangular_strip(fildes,clist,numverts,gnormals)
integer∗4 fildes,numverts
real clist(numverts∗3),gnormals((numverts−2)∗3)

Pascal Syntax:

procedure triangular_strip(fildes:integer; var clist:array[lo..hi:integer] of real; numverts:integer; var gnormals:array[lo..hi:integer] of real);

HP-UX COMPATIBILITY

Level: HP-UX/STANDARD

Origin: PHIGS+ Computer Graphics Interface

DESCRIPTION

Input Parameters

fildes Integer file descriptor returned by gopen when an I/O path to a graphics device is opened.

clist array of three dimensional real endpoint data

numverts number of strip vertices in the clist array.

gnormals array of real geometric normals.

Discussion

A boundary of a series of triangular regions is defined by connecting each vertex to its two successors in the coordinate list. The first triangle is formed from vertices 1,2,3 and the second triangle from vertices 2,3,4. The last triangle if formed from vertices numverts-2,numverts-1,numverts.

If vertex_format is specified to include a normal per polygon, then this normal is extracted from the gnormals array. The first three entries of this array are x,y,z coordinates of the normal for the first triangle. The second three entries are the normal for the second triangle and so on. If there are no normals per polygon then the gnormals value may be null.

Each triangle is filled and/or outlined according to the current interior style. Triangular_strip uses the current fill color and perimeter attributes. As with all output primitives it is affected by the current drawing mode and write enable.

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