glFogCoordPointer — define an array of fog coordinates
void glFogCoordPointer( | GLenum | type, |
GLsizei | stride, | |
GLvoid * | pointer) ; |
type
Specifies the data type of each fog coordinate.
Symbolic constants
GL_FLOAT
,
or GL_DOUBLE
are accepted. The initial value is GL_FLOAT
.
stride
Specifies the byte offset between consecutive fog coordinates.
If stride
is 0, the array elements are understood
to be tightly packed. The initial value is 0.
pointer
Specifies a pointer to the first coordinate of the first fog coordinate in the array. The initial value is 0.
glFogCoordPointer
specifies the location and data format of an array of fog coordinates
to use when rendering. type
specifies the data type of each fog
coordinate, and stride
specifies the byte stride from one fog coordinate 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 a fog coordinate 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 fog coordinate vertex array
client-side state (GL_FOG_COORD_ARRAY_BUFFER_BINDING
).
When a fog coordinate array is specified,
type
, stride
, and pointer
are saved as client-side
state, in addition to the current vertex array buffer object binding.
To enable and disable the fog coordinate array, call
glEnableClientState and glDisableClientState with the argument
GL_FOG_COORD_ARRAY
. If
enabled, the fog coordinate array is used
when glDrawArrays, glMultiDrawArrays, glDrawElements,
glMultiDrawElements, glDrawRangeElements, or
glArrayElement is called.
glFogCoordPointer
is available only if the GL version is 1.4 or greater.
Fog coordinates are not supported for interleaved vertex array formats (see glInterleavedArrays).
The fog coordinate array is initially disabled and isn't accessed when glArrayElement, glDrawElements, glDrawRangeElements, glDrawArrays, glMultiDrawArrays, or glMultiDrawElements is called.
Execution of glFogCoordPointer
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.
glFogCoordPointer
is typically implemented on the client side with no protocol.
Fog coordinate array parameters are client-side state and are therefore not saved or restored by glPushAttrib and glPopAttrib. Use glPushClientAttrib and glPopClientAttrib instead.
GL_INVALID_ENUM
is generated if type
is not either GL_FLOAT
or GL_DOUBLE
.
GL_INVALID_VALUE
is generated if stride
is negative.
glIsEnabled with argument GL_FOG_COORD_ARRAY
glGet with argument GL_FOG_COORD_ARRAY_STRIDE
glGet with argument GL_FOG_COORD_ARRAY_TYPE
glGet with argument GL_FOG_COORD_ARRAY_BUFFER_BINDING
glGet with argument GL_ARRAY_BUFFER_BINDING
glGetPointerv with argument GL_FOG_COORD_ARRAY_POINTER
glArrayElement, glBindBuffer, glColorPointer, glDisableClientState, glDrawArrays, glDrawElements, glDrawRangeElements, glEdgeFlagPointer, glEnableClientState, glFogCoord, glIndexPointer, glInterleavedArrays, glMultiDrawArrays, glMultiDrawElements, glNormalPointer, glPopClientAttrib, glPushClientAttrib, glSecondaryColorPointer, glTexCoordPointer, glVertexAttribPointer, glVertexPointer
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/.