GLEDGEFLAGPOINTER

Section: Misc. Reference Manual Pages (3G)
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NAME

glEdgeFlagPointer - define an array of edge flags

C SPECIFICATION

void glEdgeFlagPointer( GLsizei stride,


                          const GLvoid *ptr )

delim $$

PARAMETERS

stride: Specifies the byte offset between consecutive edge flags. If stride is 0 (the initial value), the edge flags are understood to be tightly packed in the array. The initial value is 0.
ptr: Specifies a pointer to the first edge flag in the array. The initial value is zero.

DESCRIPTION

glEdgeFlagPointer specifies the location and data 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. (Single-array storage may be more efficient on some implementations; see glInterleavedArrays.) When an edge flag array is specified, stride and ptr are saved as client-side state. 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, glDrawElements, or glArrayElement is called. Use glDrawArrays to construct a sequence of primitives (all of the same type) from prespecified vertex and vertex attribute arrays. Use glArrayElement to specify primitives by indexing vertices and vertex attributes and glDrawElements to construct a sequence of primitives by indexing vertices and vertex attributes.

NOTES

glEdgeFlagPointer is available only if the GL version is 1.1 or greater. The edge flag array is initially disabled and it won't be accessed when
glArrayElement, glDrawElements or glDrawArrays 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
glGetPointerv with argument GL_EDGE_FLAG_ARRAY_POINTER