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

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+'\" te
+'\"! tbl|eqn | mmdoc
+'\"macro stdmacro
+.ds Vn Version 1.2
+.ds Dt 24 September 1999
+.ds Re Release 1.2.1
+.ds Dp Jan 14 18:30
+.ds Dm 01 arrayelem
+.ds Xs 50127 5 arrayelement.gl
+.TH GLARRAYELEMENT 3G
+.SH NAME
+.B "glArrayElement
+\- render a vertex using the specified vertex array element
+
+.SH C SPECIFICATION
+void \f3glArrayElement\fP(
+GLint \fIi\fP )
+.nf
+.fi
+
+.EQ
+delim $$
+.EN
+.SH PARAMETERS
+.TP \w'\f2i\fP\ \ 'u 
+\f2i\fP
+Specifies an index into the enabled vertex data arrays. 
+.SH DESCRIPTION
+\%\f3glArrayElement\fP commands are used within \%\f3glBegin\fP/\%\f3glEnd\fP pairs to
+specify vertex and attribute data for point, line, and polygon
+primitives. If \%\f3GL_VERTEX_ARRAY\fP is enabled when \%\f3glArrayElement\fP is called, a
+single vertex is drawn, using 
+vertex and attribute data taken from location \f2i\fP of the enabled
+arrays. If \%\f3GL_VERTEX_ARRAY\fP is not enabled, no drawing occurs but
+the attributes corresponding to the enabled arrays are modified. 
+.P
+Use \%\f3glArrayElement\fP to construct primitives by indexing vertex data, rather than
+by streaming through arrays of data in first-to-last order. Because
+each call specifies only a single vertex, it is possible to explicitly
+specify per-primitive attributes such as a single normal per
+individual triangle.
+.P
+Changes made to array data between the execution of \%\f3glBegin\fP and the 
+corresponding execution of \%\f3glEnd\fP may affect calls to \%\f3glArrayElement\fP that are made
+within the same \%\f3glBegin\fP/\%\f3glEnd\fP period in non-sequential ways.
+That is, a call to 
+.br
+\%\f3glArrayElement\fP that precedes a change to array data may 
+access the changed data, and a call that follows a change to array data 
+may access original data.
+.SH NOTES
+\%\f3glArrayElement\fP is available only if the GL version is 1.1 or greater.
+.P
+\%\f3glArrayElement\fP is included in display lists. If \%\f3glArrayElement\fP is entered into a
+display list, the necessary array data (determined by the array
+pointers and enables) is also entered into the display list. Because
+the array pointers and enables are client-side state, their values
+affect display lists when the lists are created, not when the lists
+are executed.
+.SH SEE ALSO 
+\%\f3glClientActiveTextureARB(3G)\fP,
+\%\f3glColorPointer(3G)\fP,
+\%\f3glDrawArrays(3G)\fP,
+\%\f3glEdgeFlagPointer(3G)\fP,
+\%\f3glGetPointerv(3G)\fP,
+\%\f3glIndexPointer(3G)\fP,
+\%\f3glInterleavedArrays(3G)\fP,
+\%\f3glNormalPointer(3G)\fP,
+\%\f3glTexCoordPointer(3G)\fP,
+\%\f3glVertexPointer(3G)\fP