QUADRILATERAL_MESH(3G)

NAME

quadrilateral_mesh − defines a series of quadrilateral regions to be filled and/or edged.

SYNOPSIS

C Syntax:

void quadrilateral_mesh(fildes,clist, numverts_m,numverts_n,gnormals);

int fildes,numverts_m,numverts_n;

float clist[],gnormals[];

FORTRAN77 Syntax:

subroutine quadrilateral_mesh(fildes,clist, numverts_m,numverts_n,gnormals)

integer∗4 fildes,numverts_m,numverts_n

real clist(numverts_m∗numverts_n∗3), gnormals((numverts_m−1)∗(numverts_n−1)∗3)

Pascal Syntax:

procedure quadrilateral_mesh(fildes:integer; var clist:array[lo..hi:integer] of real; numverts_m,numverts_n: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 stored in row major format

numverts_m number of rows in the clist array.

numverts_n number of columns in the clist array.

gnormals array of real geometric normals.

Discussion

The list of points is a two dimensional array where each set of four neighboring points defines a quadrilateral. The first quadrilateral consists of the first two points from the first row and the first two points from the second row. The second quadrilateral consists of the second and third points from the first row and the second and third points from the second row and so on.

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 quadrilateral. The second three entries are the normal for the second quadrilateral if normals per vertex are present, and so on. If there are no normals per polygon then the gnormals value may be null.

The sense of the CLOCKWISE/COUNTER_CLOCKWISE direction of polygon vertices is determined by the 1st, 2nd and 3rd vertex in each quadrilateral.

For example: The 1st vertex in the 1st row is the 1st vertex of the first quadrilateral. The 2nd vertex in the 1st row is the 2nd vertex of the first quadrilateral. The 2nd vertex in the 2nd row is the 3rd vertex of the first quadrilateral.

Each quadrilateral is filled and/or outlined according to the current interior style. Quadrilateral_mesh 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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