1991-2006
Silicon Graphics, Inc.
glEdgeFlagPointer
3G

# glEdgeFlagPointer

define an array of edge flags

## C Specification

                    void glEdgeFlagPointer
                    GLsizei stride
                    const GLvoid * pointer

## Parameters

`stride`

  Specifies the byte offset between consecutive edge flags. If `stride` is 0, the edge flags are understood to be tightly packed in the array. The initial value is 0.

`pointer`

  Specifies a pointer to the first edge flag in the array. The initial value is 0.

## Description

`glEdgeFlagPointer` specifies the location and data format of an array of boolean edge flags to use when rendering. `stride` specifies the byte stride from one edge flag to the next, allowing vertices and attributes to be packed into a single array or stored in separate arrays.

If a non-zero named buffer object is bound to the `GL_ARRAY_BUFFER` target (see glBindBuffer) while an edge flag array is specified, `pointer` is treated as a byte offset into the buffer object's data store. Also, the buffer object binding (`GL_ARRAY_BUFFER_BINDING`) is saved as edge flag vertex array client-side state (`GL_EDGE_FLAG_ARRAY_BUFFER_BINDING`).

When an edge flag array is specified, `stride` and `pointer` are saved as client-side state, in addition to the current vertex array buffer object binding.

To enable and disable the edge flag array, call glEnableClientState and glDisableClientState with the argument `GL_EDGE_FLAG_ARRAY`. If enabled, the edge flag array is used when glDrawArrays, glMultiDrawArrays, glDrawElements, glMultiDrawElements, glDrawRangeElements, or glArrayElement is called.

## Notes

`glEdgeFlagPointer` is available only if the GL version is 1.1 or greater.

Edge flags are not supported for interleaved vertex array formats (see glInterleavedArrays).

The edge flag array is initially disabled and isn't accessed when glArrayElement, glDrawElements, glDrawRangeElements, glDrawArrays, glMultiDrawArrays, or glMultiDrawElements is called.

Execution of `glEdgeFlagPointer` is not allowed between the execution of glBegin and the corresponding execution of glEnd, but an error may or may not be generated. If no error is generated, the operation is undefined.

`glEdgeFlagPointer` is typically implemented on the client side.

Edge flag array parameters are client-side state and are therefore not saved or restored by glPushAttrib and glPopAttrib. Use glPushClientAttrib and glPopClientAttrib instead.

## Errors

`GL_INVALID_ENUM` is generated if `stride` is negative.

## Associated Gets

glIsEnabled with argument `GL_EDGE_FLAG_ARRAY`

glGet with argument `GL_EDGE_FLAG_ARRAY_STRIDE`

glGet with argument `GL_EDGE_FLAG_ARRAY_BUFFER_BINDING`

glGet with argument `GL_ARRAY_BUFFER_BINDING`

glGetPointerv with argument `GL_EDGE_FLAG_ARRAY_POINTER`

## See Also

glArrayElement, glBindBuffer, glColorPointer, glDisableClientState, glDrawArrays, glDrawElements, glDrawRangeElements, glEdgeFlag, glEnableClientState, glFogCoordPointer, glIndexPointer, glInterleavedArrays, glMultiDrawArrays, glMultiDrawElements, glNormalPointer, glPopClientAttrib, glPushClientAttrib, glSecondaryColorPointer, glTexCoordPointer, glVertexAttribPointer, glVertexPointer

## Copyright

Copyright 1991-2006 Silicon Graphics, Inc. This document is licensed under the SGI Free Software B License. For details, see http://oss.sgi.com/projects/FreeB/.