glGetTexEnv Subroutine

OpenGL 1.1 for AIX: Reference Manual

glGetTexEnv Subroutine

Purpose

Returns texture environment parameters.

Library

OpenGL C bindings library: libGL.a

C Syntax

void glGetTexEnvfv(GLenum Target,
      GLenum ParameterName,
      GLfloat *ParameterValues)

void glGetTexEnviv(GLenum Target,
      GLenum ParameterName,
      GLint *ParameterValues)

Parameters

Target	Specifies a texture environment. Must be GL_TEXTURE_ENV.
ParameterName	Specifies the symbolic name of a texture environment parameter. Accepted values are GL_TEXTURE_ENV_MODE and GL_TEXTURE_ENV_COLOR.
ParameterValues	Returns the requested data.

Description

The glGetTexEnv subroutine returns in the ParameterValues parameter selected values of a texture environment that was specified with glTexEnv. The Target parameter specifies a texture environment. Currently only the GL_TEXTURE_ENV texture environment is defined and supported.

ParameterName names a specific texture environment parameter. The two parameters are:

GL_TEXTURE_ENV_MODE	ParameterValues returns the single-valued texture environment mode, a symbolic constant.
GL_TEXTURE_ENV_COLOR	ParameterValues returns four integer or floating-point values that are the texture environment color. Integer values, when requested, are linearly mapped from the internal floating-point representation such that 1.0 maps to the most positive representable integer, and -1.0 maps to the most negative representable integer.

Notes

If an error is generated, no change is made to the contents of ParameterValues.

Errors

GL_INVALID_ENUM	Either Target or ParameterName is not an accepted value.
GL_INVALID_OPERATION	The glGetTexEnv subroutine is called between a call to glBegin and the corresponding call to glEnd.

Files

/usr/include/GL/gl.h

Contains C language constants, variable type definitions, and ANSI function prototypes for OpenGL.

Related Information

The glBegin or glEnd subroutine, glTexEnv subroutine.

OpenGL Overview.