NAME

texture_viewport − specify a mapping area for subsequent texture_windows

SYNOPSIS

C Syntax:

void texture_viewport ( fildes, s1, t1, s2, t2 );
int fildes;
float s1, t1, s2, t2;

FORTRAN77 Syntax:

subroutine texture_viewport ( fildes, s1, t1, s2, t2 )
integer*4 fildes
real s1, t1, s2, t2

Pascal Syntax:

procedure texture_viewport ( fildes:integer;
s1, t1, s2, t2:real );

DESCRIPTION

Input Parameters

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

s1, t1, s2, t2 Boundaries of the new viewport on a unit square. 

Discussion

This procedure specifies the rectangle onto which the four coordinate values of texture_window map. texture_viewport is used to align a texture map with the given texture_window coordinates.  Rendered repetitions of the texture map or values of the rendered texture map external to the texture_window coordinates are based on the entire texture map regardless of the texture_viewport settings. 

If a value less than zero or greater than one is specified for any s or t coordinate, then an error is generated and the default values are used. 

DEFAULTS

(s1, t1)=(0.0, 0.0), (s2, t2)=(1.0, 1.0)

SEE ALSO

define_texture(3G), texture_window(3G).  Starbase Device Drivers Manual. 

Hewlett-Packard Company  —  November 03, 1994