NAME
fglCallLists - execute a list of display lists
FORTRAN SPECIFICATION
SUBROUTINE fglCallLists( INTEGER*4 n,
INTEGER*4 type,
CHARACTER*8 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
fglCallLists 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.
fglCallLists 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
-128 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 -32768 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 fglListBase command, which specifies an unsigned offset
that is added to each display-list name specified in lists
before that display list is executed.
fglCallLists 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
fglCallLists. Thus, changes made to GL state during the
execution of the display lists remain after execution is
completed. Use fglPushAttrib, fglPopAttrib, fglPushMatrix,
and fglPopMatrix to preserve GL state across fglCallLists
calls.
NOTES
Display lists can be executed between a call to fglBegin and
the corresponding call to fglEnd, 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
fglGet with argument GL_LIST_BASE
fglGet with argument GL_MAX_LIST_NESTING
fglIsList
SEE ALSO
fglCallList, fglDeleteLists, fglGenLists, fglListBase,
fglNewList, fglPushAttrib,
fglPushMatrix