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doc/gl-docs/GL/gl/activetextureARB.3gl

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+.\" $XFree86$
+'\" et
+'\"! eqn|tbl | mmdoc
+'\"macro stdmacro
+.ds Vn Version 1.2
+.ds Dt 24 September 1999
+.ds Re Release 1.2.1
+.ds Dp Jan 14 19:46
+.ds Dm 01 activetex
+.ds Xs 15390 4 activetextureARB.gl
+.TH GLACTIVETEXTUREARB 3G
+.SH NAME
+.B "glActiveTextureARB
+\- select active texture unit
+
+.SH C SPECIFICATION
+void \f3glActiveTextureARB\fP(
+GLenum \fItexture\fP )
+.nf
+.fi
+
+.EQ
+delim $$
+.EN
+.SH PARAMETERS
+.TP \w'\f2texture\fP\ \ 'u 
+\f2texture\fP
+Specifies which texture unit to make active. The number
+of texture units is implementation dependent, but must be at least
+two. \f2texture\fP must be one of \%\f3GL_TEXTURE\fP$i$\f3_ARB\fP, where 
+0 \(<= $ i $ < \%\f3GL_MAX_TEXTURE_UNITS_ARB\fP, which is an
+implementation-dependent value.  The initial value is \%\f3GL_TEXTURE0_ARB\fP.
+.SH DESCRIPTION
+\%\f3glActiveTextureARB\fP selects which texture unit subsequent texture state calls will
+affect.  The number of texture units an implementation supports is
+implementation dependent, but must be at least 2.
+.P
+Vertex arrays are client-side GL resources, which are selected by the 
+\%\f3glClientActiveTextureARB\fP routine.
+.SH NOTES
+\%\f3glActiveTextureARB\fP is only supported if \%\f3GL_ARB_multitexture\fP is included in the
+string returned by \%\f3glGetString\fP when called with the argument
+\%\f3GL_EXTENSIONS\fP.
+.SH ERRORS 
+\%\f3GL_INVALID_ENUM\fP is generated if \f2texture\fP is not one of
+\%\f3GL_TEXTURE\fP$i$\f3_ARB\fP,
+.br
+where 0 \(<= $ i $ < \%\f3GL_MAX_TEXTURE_UNITS_ARB\fP.
+.SH SEE ALSO
+\%\f3glClientActiveTextureARB(3G)\fP,
+\%\f3glGetIntegerv(3G)\fP,
+\%\f3glMultiTexCoordARB(3G)\fP,
+\%\f3glTexParameter(3G)\fP
+