Silicon Graphics IRIS Workstation, Руководство пользователя

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Appendix L: GL 1 and GL 1.9 Software Differences
This document describes the differences between release 1 of the graphics
library (the standard release) and the version that is used in the IRIS terminal
programming environment. The programming environment is a small part of
GL 2 -- a project involving major hardware and software enhancements. Much
of the GL 2 software will run on old hardware, and we provide a subset of that
new software as the preliminary programming environment. GL 1 and GL 2
are not completely compatible, but are nearly so. When it is important to
distinguish between the terminal programming environment and the full GL 2,
we will call the terminal programming environment GL 1.9; otherwise, we call
them both GL 2.
L.1 Miscellaneous Changes
•
bbox()
and
bboxi()
are not available.
• Object fonts are not available.
•
curve()
accepts only a geometry matrix. The basis and precision
matrices are specified separately (see curve section).
•
modify()
is not available.
• The name of
sync()
has changed to
gsync()
.
sync()
conflicts with a UNIX
system call.
• The type definition for
RGBvalue
is now unsigned char (instead of
short).
•
swapbuffers()
can be put into a display list.
L.2 Display List Editing
Internal Format
Display list internal format has changed to make insertion/deletion more
efficient. Graphical objects now use a linked structure that is occasionally
compacted. This makes better use of memory—even if the IRIS’ main memory
is badly fragmented, it will all be available for display list space, since even
a long display list can be kept in pieces. When an object is closed, it may be
Version 1.0