GLEDGEFLAGPOINTER(3G)

NAME
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/.