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OpenGL 1.1 for AIX: Reference Manual

glEdgeFlagPointerEXT Subroutine


Defines an array of edge flags.


OpenGL C bindings library: libGL.a

C Syntax

void glEdgeFlagPointerEXT(GLsizei stride, 
                  GLsizei count, 
                  const GLboolean *pointer)


stride Specifies the byte offset between consecutive edge flags. If stride is zero the edge flags are understood to be tightly packed in the array.
count Specifies the number of edge flags, counting from the first, that are static.
pointer Specifies a pointer to the first edge flag in the array.


glEdgeFlagPointerEXT specifies the location and data format of an array of boolean edge flags to use when rendering. stride gives the byte stride from one edge flag to the next allowing vertexes and attributes to be packed into a single array or stored in separate arrays. (Single-array storage may be more efficient on some implementations.) count indicates the number of array elements (counting from the first) that are static. Static elements may be modified by the application, but once they are modified, the application must explicitly respecify the array before using it for any rendering. When an edge flag array is specified, stride, count and pointer are saved as client-side state, and static array elements may be cached by the implementation.

The edge flag array is enabled and disabled using glEnable and glDisable with the argument GL_EDGE_FLAG_ARRAY_EXT. If enabled, the edge flag array is used when glDrawArraysEXT or glArrayElementEXT is called.

Use glDrawArraysEXT to define a sequence of primitives (all of the same type) from pre-specified vertex and vertex attribute arrays. Use glArrayElementEXT to specify primitives by indexing vertexes and vertex attributes.


Non-static array elements are not accessed until glArrayElementEXT or glDrawArraysEXT is executed.

By default the edge flag array is disabled and it won't be accessed when glArrayElementEXT or glDrawArraysEXT is called.

Although, it is not an error to call glEdgeFlagPointerEXT between the execution of glBegin and the corresponding execution of glEnd, the results are undefined.

glEdgeFlagPointerEXT will typically be implemented on the client side with no protocol.

Since the edge flag array parameters are client side state, they are not saved or restored by glPushAttrib and glPopAttrib.

glEdgeFlagPointerEXT commands are not entered into display lists.

glEdgeFlagPointerEXT is part of the _extname(EXT_vertex_array) extension, not part of the core GL command set. If _extstring(EXT_vertex_array) is included in the string returned by glGetString, when called with argument GL_EXTENSIONS, extension _extname(EXT_vertex_array) is supported.


GL_INVALID_ENUM is generated if stride or count is negative.

Associated Gets

glIsEnabled with argument GL_EDGE_FLAG_ARRAY_EXT


glGet with argument GL_EDGE_FLAG_ARRAY_COUNT_EXT

glGetPointervEXT with argument GL_EDGE_FLAG_ARRAY_POINTER_EXT


/usr/include/GL/glext.h Contains extensions to C language constants, variable type definitions, and ANSI function prototypes for OpenGL.

Related Information

The glArrayElementEXT subroutine, glColorPointerEXT subroutine, glDrawArraysEXT subroutine, glGetPointervEXT subroutine, glIndexPointerEXT subroutine, glNormalPointerEXT subroutine, glTexCoordPointerEXT subroutine, glVertexPointerEXT subroutine.

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