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.
