Gl.CallLists (gb.opengl)
Execute a list of display lists.
Parameters
- n
-
Specifies the number of display lists to be executed.
- type
-
Specifies the type of values in lists.
Symbolic constants
Gl.BYTE,
Gl.UNSIGNED_BYTE,
Gl.SHORT,
Gl.UNSIGNED_SHORT,
Gl.INT,
Gl.UNSIGNED_INT,
Gl.FLOAT,
Gl.2_BYTES,
Gl.3_BYTES, and
Gl.4_BYTES are accepted.
- lists
-
Specifies the address of an array of name offsets in the display list.
The pointer type is void because the offsets can be bytes,
shorts,
ints,
or floats,
depending on the value of type.
Description
Gl.CallLists causes each display list in the list of names passed as
lists
to be executed.
As a result,
the commands saved in each display list are executed in order,
just as if they were called without using a display list.
Names of display lists that have not been defined are ignored.
Gl.CallLists provides an efficient means for executing more than one display list.
type allows lists with various name formats to be accepted.
The formats are as
follows:
- Gl.BYTE
-
lists is treated as an array of signed bytes,
each in the range
through 127.
- Gl.UNSIGNED_BYTE
-
lists is treated as an array of unsigned bytes,
each in the range 0 through 255.
- Gl.SHORT
-
lists is treated as an array of signed two-byte integers,
each in the range
through 32767.
- Gl.UNSIGNED_SHORT
-
lists is treated as an array of unsigned two-byte integers,
each in the range 0 through 65535.
- Gl.INT
-
lists is treated as an array of signed four-byte integers.
- Gl.UNSIGNED_INT
-
lists is treated as an array of unsigned four-byte integers.
- Gl.FLOAT
-
lists is treated as an array of four-byte floating-point values.
- Gl.2_BYTES
-
lists is treated as an array of unsigned bytes.
Each pair of bytes specifies a single display-list name.
The value of the pair is computed as 256 times the unsigned value
of the first byte plus the unsigned value of the second byte.
- Gl.3_BYTES
-
lists is treated as an array of unsigned bytes.
Each triplet of bytes specifies a single display-list name.
The value of the triplet is computed as 65536 times the unsigned value
of the first byte,
plus 256 times the unsigned value of the second byte,
plus the unsigned value of the third byte.
- Gl.4_BYTES
-
lists is treated as an array of unsigned bytes.
Each quadruplet of bytes specifies a single display-list name.
The value of the quadruplet is computed as 16777216 times the unsigned value
of the first byte,
plus 65536 times the unsigned value of the second byte,
plus 256 times the unsigned value of the third byte,
plus the unsigned value of the fourth byte.
The list of display-list names is not null-terminated.
Rather,
n specifies how many names are to be taken from
lists.
An additional level of indirection is made available with the
Gl.ListBase command,
which specifies an unsigned offset that is added to each display-list
name specified in
lists before that display list is executed.
Gl.CallLists can appear inside a display list.
To avoid the possibility of infinite recursion resulting from display lists
calling one another,
a limit is placed on the nesting level of display
lists during display-list execution.
This limit must be at least 64, and it depends on the implementation.
GL state is not saved and restored across a call to
Gl.CallLists.
Thus,
changes made to GL state during the execution of the display lists
remain after execution is completed.
Use Gl.PushAttrib,
Gl.PopAttrib,
Gl.PushMatrix,
and
Gl.PopMatrix to preserve GL state across
Gl.CallLists calls.
Notes
Display lists can be executed between a call to
Gl.Begin
and the corresponding call to
Gl.End,
as long as the display list includes only commands that are allowed
in this interval.
Errors
Gl.INVALID_VALUE is generated if
n is negative.
Gl.INVALID_ENUM is generated if
type is not one of
Gl.BYTE,
Gl.UNSIGNED_BYTE,
Gl.SHORT,
Gl.UNSIGNED_SHORT,
Gl.INT,
Gl.UNSIGNED_INT,
Gl.FLOAT,
Gl.2_BYTES,
Gl.3_BYTES,
Gl.4_BYTES.
Associated Gets
Gl.Get with argument Gl.LIST_BASE
Gl.Get with argument Gl.MAX_LIST_NESTING
Gl.IsList
See Also
Gl.CallList,
Gl.DeleteLists,
Gl.GenLists,
Gl.ListBase,
Gl.NewList,
Gl.PushAttrib,
Gl.PushMatrix
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.
➡ See original documentation