glArrayElement(3G) — Subroutines
NAME
glArrayElement − render a vertex using the specified vertex array element
SYNOPSIS
void glArrayElement(
GLint i );
PARAMETERS
iSpecifies 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 i of the enabled arrays. If GL_VERTEX_ARRAY is not enabled, no drawing occurs but the attributes corresponding 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 individual 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 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.
SEE ALSO
glClientActiveTextureARB(3), glColorPointer(3), glDrawArrays(3), glEdgeFlagPointer(3), glGetPointerv(3), glIndexPointer(3), glInterleavedArrays(3), glNormalPointer(3), glTexCoordPointer(3), glVertexPointer(3)