- render a vertex using the specified vertex array element
C SPECIFICATION
PARAMETERS
_param1 Specifies an index into the enabled vertex data
arrays.
DESCRIPTION
glArrayElement commands are used within glBegin/glEnd
pairs to specify vertex and attribute data for point,
line, and polygon primitives. If GL_VERTEX_ARRAY is
enabled when glArrayElement is called, a single vertex is
drawn, using vertex and attribute data taken from location
_param1 of the enabled arrays. If GL_VERTEX_ARRAY is not
enabled, no drawing occurs but the attributes correspond-
ing to the enabled arrays are modified.
Use glArrayElement 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 indi-
vidual triangle.
Changes made to array data between the execution of
glBegin and the corresponding execution of glEnd may
affect calls to glArrayElement that are made within the
same glBegin/glEnd period in non-sequential ways. That
is, a call to
glArrayElement 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.
NOTES
glArrayElement is available only if the GL version is 1.1
or greater.
glArrayElement is included in display lists. If
glArrayElement is entered into a display list, the neces-
sary 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 cre-
ated, not when the lists are executed.
SEE ALSO
glClientActiveTextureARB, glColorPointer, glDrawArrays,
glEdgeFlagPointer, glGetPointerv, glIndexPointer,
glInterleavedArrays, glNormalPointer, glTexCoordPointer,
glVertexPointer