rpatch Subroutine

GL3.2 for AIX: Graphics Library (GL) Technical Reference

Draws a rational surface patch.

Graphics Library

C (libgl.a)

FORTRAN (libfgl.a)

void rpatch
(Matrix geomx, Matrix geomy,
Matrix geomz, Matrix geomw)

SUBROUTINE RPATCH(geomx, geomy, geomz, geomw)
REAL geomx(4,4), geomy(4,4), geomz(4,4), geomw(4,4)

The rpatch subroutine draws a rational surface patch using the current settings from the patchbasis, patchprecision, and patchcurves subroutines. The control points geomx, geomy, geomz, and geomw determine the shape of the patch.

geomx	Specifies a 4x4 matrix containing the x coordinates of the 16 control points of the patch.
geomy	Specifies a 4x4 matrix containing the y coordinates of the 16 control points of the patch.
geomz	Specifies a 4x4 matrix containing the z coordinates of the 16 control points of the patch.
geomw	Specifies a 4x4 matrix containing the w coordinates of the 16 control points of the patch.

This subroutine is part of GL in the AIXwindows Environment/6000 Version 1, Release 2 with AIXwindows/3D Feature.

/usr/include/gl/gl.h	Contains C language constant and variable type definitions for GL.
/usr/include/gl/fgl.h	Contains FORTRAN constant and variable type definitions for GL.

Defining a cubic spline basis matrix with the defbasis subroutine.

Drawing a surface patch with the patch subroutine.

Setting the current spline surface basis matrices with the patchbasis subroutine.

Setting the number of curves used to represent a patch with the patchcurves subroutine.

Setting the precision at which curves are drawn with the patchprecision subroutine.