Glarrayelement - HP b2600 Reference Manual

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glArrayElement

glArrayElement
glArrayElement: render a vertex using the specified vertex array element.
C Specification
void glArrayElement(
GLint i)
Parameters
i 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 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
glColorPointer,
glDrawArrays,
glEdgeFlagPointer,
glGetPointer,
glIndexPointer,
glInterleavedArrays,
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Chapter 1