Glrad
renders a Radiance scene description in OpenGL.
Its syntax and behavior is similar to
rad(1)
with the
-o
option, where the output device is assumed to be an X11 server
with GLX extensions.
The
-w
option turns off warnings.
The
-s
option tells
glrad
to run
rad
silently, not echoing
oconv(1)
command.
The
-b
option turns off back face visibility (i.e., enables back face culling).
This is equivalent to the
-bv
option of
rpict(1)
and
rvu(1).
The
-S
option turns on full-screen stereo for displays that support it.
(Be sure to run
/usr/gfx/setmon(1)
or its equivalent to set STR_TOP or STR_BOT, first.)
The
-v
option may be used to specify a starting view, either by symbolic name
as entered in the
view
assignments in
rfile,
or by a complete view specification, enclosed in quotes.
If no view is specified, then the first standard view from
rfile
is used to start.
Variables permitted in
rfile
are described in the
rad
manual page.
Additional or overriding assignments may be given on the command line
following
rfile.
The view is controlled via the mouse and simple one-character commands,
listed below:
(mouse)
Modify the current view.
The mouse is used to control the current view in the following ways:
CONTROL MOUSE ACTION
(none) left Move forward towards cursor position
(none) right Move backward away from cursor position
(none) middle Rotate in place (usually safe)
shift left Orbit left around cursor position
shift right Orbit right around cursor position
shift middle Orbit skyward
cntl middle Orbit earthward
For all movements but rotating in place, the cursor must be placed over some
bit of visible geometry, otherwise the program has no reference point from
which to work.
It is best to just experiment with these controls until you learn to fly
safely in your model.
And if you run into trouble, the 'l' command is very useful.
(See below.)
'+'
Zoom in on the current cursor position.
(Beware of repeating keys that go faster than the display updates.)
'-'
Zoom out from the current cursor position.
'l'
Return to the last saved view.
Each time a new command changes the current view, the last view
is saved, and may be recalled with this command.
Multiple uses of the same command (e.g., rotation, zoom) will
save only the view before the first such command.
This way, it is easy to get back to where you were before a sequence
of view changes.
'h'
Fix the head height.
All mouse-controlled view motions will be adjusted so that the head height
does not change (where vertical is determined by the current
view up vector).
'H'
Release the head height, allowing it to change again during mouse-controlled
movements.
'v'
Print the current view parameters to the standard output.
This is useful for finding out where you are, or for saving specific
views in a keyframe file for animations or returning to later.
'V'
Append the current view to the original
rfile.
This view will be unnamed, but can be referred to by number or the
user may add a name later with a text editor.
The current view number becomes the last standard view.
(See the 'n' and 'p' commands, below.)
'n'
Go to the next standard view stored in
rfile.
If the last view is currently displayed, then cycle to the first one.
'p'
Go to the previous standard view stored in
rfile.
If the first view is currently displayed, then cycle to the last one.
'q'
Quit
glrad.
This is the normal way to exit the program.
AUTHOR
Greg Ward Larson
BUGS
It would be nice if
glrad
set the appropriate video format for stereo viewing automatically,
but the process is different on different systems and there is no
single, sure-fire way to do it for all systems.
On systems that do not support stereo extensions, the program
may be compiled with the -DNOSTEREO option, which will avoid
undefined symbol errors.