GLGETTEXENV

Section: Misc. Reference Manual Pages (3G)
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NAME

glGetTexEnvfv, glGetTexEnviv - return texture environment parameters

C SPECIFICATION

void glGetTexEnvfv( GLenum target,


                      GLenum pname,
                      GLfloat *params )

void glGetTexEnviv( GLenum target,


                      GLenum pname,
                      GLint *params )

PARAMETERS

target: Specifies a texture environment. Must be GL_TEXTURE_ENV.
pname: Specifies the symbolic name of a texture environment parameter. Accepted values are GL_TEXTURE_ENV_MODE and GL_TEXTURE_ENV_COLOR.
params: Returns the requested data.

DESCRIPTION

glGetTexEnv returns in params selected values of a texture environment that was specified with glTexEnv. target specifies a texture environment. Currently, only one texture environment is defined and supported: GL_TEXTURE_ENV.

pname names a specific texture environment parameter, as follows:

GL_TEXTURE_ENV_MODE: params returns the single-valued texture environment mode, a symbolic constant. The initial value is GL_MODULATE.
GL_TEXTURE_ENV_COLOR: params 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. The initial value is (0, 0, 0, 0).

NOTES

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

When the GL_ARB_multitexture extension is supported, glGetTexEnv returns the texture environment parameters for the active texture unit.

ERRORS

GL_INVALID_ENUM is generated if target or pname is not an accepted value.

GL_INVALID_OPERATION is generated if glGetTexEnv is executed between the execution of glBegin and the corresponding execution of glEnd.