I have done a patch to eliminate the jitter of 3D-objects near the viewpoint
(for example 3D cockpit objects).
The problem is the roundoff accuracy of the float values used in the
scenegraph together with the transforms of the eyepoint relative to the
scenery center.
The solution will be to move the scenery center near the view point.
This way floats relative accuracy is enough to show a stable picture.
To get that right I have introduced a transform node for the scenegraph which
is responsible for that shift and uses double values as long as possible.
The scenery subsystem now has a list of all those transforms required to place
objects in the world and will tell all those transforms that the scenery
center has changed when the set_scenery_center() of the scenery subsystem is
called.
The problem was not solvable by SGModelPlacement and SGLocation, since not all
objects, especially the scenery, are placed using these classes.
The first approach was to have the scenery center exactly at the eyepoint.
This works well for the cockpit.
But then the ground jitters a bit below the aircraft. With our default views
you can't see that, but that F-18 has a camera view below the left engine
intake with the nose gear and the ground in its field of view, here I could
see that.
Having the scenery center constant will still have this roundoff problems, but
like it is now too, the roundoff error here is exactly the same in each
frame, so you will not notice any jitter.
The real solution is now to keep the scenery center constant as long as it is
in a ball of 30m radius around the view point. If the scenery center is
outside this ball, just put it at the view point.
As a sideeffect of now beeing able to switch the scenery center in the whole
scenegraph with one function call, I was able to remove a one half of a
problem when switching views, where the scenery center was far off for one or
two frames past switching from one view to the next. Also included is a fix
to the other half of this problem, where the view position was not yet copied
into a view when it is switched (at least under glut). This was responsible
for the 'Error: ...' messages of the cloud subsystem when views were
switched.
a safe undersleep() to conserve cpu. Essentially we undersleep our target by
just a bit (to avoid the chance of oversleeping.) Then we finish off the
remaining time slice with a busy-wait loop.
Norman Vine wrote :
> Frederic Bouvier writes:
>
>> Quoting Andy Ross:
>>> * Hopefully in a CPU-friendly way. I know that older versions of
>>> the NVidia drivers did this by spinning in a polling loop
>>> inside the driver. I'm not sure if this has been fixed or not.
>>>
>>> From my experience, the latest non-beta Windows NVidia driver seems to eat CPU
>>
>> even with sync to vblank enabled. The CPU usage is always 100%.
>
> Buried in the PPE sources is a 'hackish' but portable way to limit CPU usage if the desired framerate is met
>
> /*
> Frame Rate Limiter.
>
> This prevents any one 3D window from updating faster than
> about 60Hz. This saves a ton of CPU time on fast machines.
>
> ! I THINK I MUNGED THE VALUE FOR ulMilliSecondSleep() NHV !
> */
>
> static ulClock *ck = NULL ;
>
> if ( frame_rate_limiter )
> {
> if ( ck == NULL )
> {
> ck = new ulClock ;
> ck -> update () ;
> }
>
> int t_ms = (int) ( ck->getDeltaTime() * 1000.0 ) ; /* Convert to ms */
>
> if ( t_ms < 16 )
> ulMilliSecondSleep ( 16 - t_ms ) ;
> }
>
>
I implemented the method pointed out by Norman. It works great on windows and saves me a lot of CPU cycles. This way, I can get the same framerate in moderately populated areas and have CPU idle 50% of the time instead of wildly looping in the NVidia driver while waiting to sync on vblank.
It has been tested on Linux by Melchior. He saw the same gain in CPU cycles.
I've finished the emigration of the radiostack, and I've also removed it
completely. It turned out that the comm radio is completely implemented in
the ATC subsystem. I've changed the affected ATC files to point
to /instrumentation/com, but I guess that the maintainer of the ATC code
should decide wether to make it configureable, and how.
I also had to change some files in Network and Main. The changes in network
should be obvious, but the changes in Main were a bit suspect. The files
included radiostack.hxx, but they weren't directly depending on
radiostack-hxx. They were depending on other files that were included by
radiostack.hxx. I got it to compile, but I'm not sure if I included the
correct directly depending file.
For the data directory I changed every occurrence of /radios/
with /instrumentation/ with this simple one-liner that I found on the net:
find -name '*.xml' -type f | xargs perl -pi -e
's/\/radios\//\/instrumentation\//g'
Instead of me sending all the files that got changed by this I suggest that
you execute the one-liner yourself. Of course I can not guarantee that this
will work perfectly, but I considered hand editing to be not an option (I'm
lazy). I don't want to test every aircraft to see if everything still works,
I think it's better to wait and see if anyone complaints about broken nav
radios/instruments.
Don't overwrite user settings from config files.
fgfs had in any case set bump-mapping to false, no matter if this
node did already exist (because it was defined in a config file).
This is a patch to make display list usage optional. They are on by default.
Use --prop:/sim/rendering/use-display-list=false to use immediate mode.
There is also a change in exception handling in main.cxx and bootstrap.cxx
Split up main.cxx into a program manegement part (which remains in
main.cxx) and a render part (the new renderer.?xx files). Also turn
the renderer into a small class of it's own. At this time not really
exctining because most of the stuff is still global, but it allows us
to slowly migrate some of the global definitions into the new class.
The FGRenderer class is now managed by globals, so to get the renderer
just call gloabals->get_renderer()
At some pijt it might be a good idea to also turn the remaining code in
main into a class of it's own. With a bit of luck we end up with a more
robust, and better maintainable code.
1. The listener is always positioned at the origin.
2. All sounds eminate from the aircraft's model position.
3. Sound positions are relative to the listener location.
my code was accidentally drawing the cockpit twice
in view 0. This patch should fix the problem of
lights not seen through canopies or prop discs.
It was also drawing the lights ( ground and rw )
after the clouds, so they were not obscured by
them.
I restored the output to cout / cerr
for the options and the warning for the version mismatch.
There is a dummy SG_LOG to allow the windows version to
popup the console.
The snapshot rendering use multipass now.
FG_ENABLE_MULTIPASS_CLOUDS must be defined to enable
the algorithm. I made this because the stencil buffer
must be initialized at the beginning of the program and
OpenGL can fallback to software rendering if it can't
find a visual with stencil buffer. I didn't touch the
configure script, so CXXFLAGS=-DFG_ENABLE_MULTIPASS_CLOUDS
must be set before running ./configure.
If FG_ENABLE_MULTIPASS_CLOUDS is defined, the main render
loop begins by reading the /sim/rendering/multi-pass-clouds
property. It is a boolean property so there are only two
quality levels. false means no multi pass and no use of
the stencil buffer, true means an additionnal pass for
both upper and lower cloud layers.
The algorithms are as follow :
/sim/rendering/multi-pass-clouds=false
1. draw sky dome
2. draw terrain only
3. draw clouds above the viewer
4. draw models except the aircraft
5. draw clouds below the viewer
6. draw the aircraft.
The cloud rendering doesn't update the depth buffer.
This means that models overwrite clouds above the viewer.
This is only noticeable for tall buildings and when
flying very low. Also, drawing low clouds after models
means that they are not blended with models' translucent
surfaces. Large transparent area require alpha test
enabled and AI aircraft canopy are making holes. The
pilot's aircraft being rendered at the end, there is no
problem with canopy or prop disc.
/sim/rendering/multi-pass-clouds=true
1. draw the sky dome
2. draw the terrain only
3. draw all clouds
4. draw models except the aircraft
5. redraw the clouds where the models where drawn ( stencil
test on )
6. draw the aircraft
The assumptions made by this algoritm are that the terrain
is not transparent ( should be true in all cases and
that there are no clouds between the aircraft and the viewer.
Assuming these facts, there should be no blending bugs.
The screenshot rendering is not updated yet.
trying the --show-aircraft option, I noticed that I had
no output. This is because there are still output to
cout or cerr, that are not triggering my console patch
for windows. The patch attached use SG_LOG instead.
A request to hit a key is also added because otherwise,
the console window will disappear as soon as the program
stop.
This problem is minor though given the fact that fgfs.exe
is shipped with fgrun that do show the available aircraft
in a much nicer manner.
places now use sgCartToGeod() instead of rolling their own
approximation. And YASim is now using exactly the same 3D coordinate
system as the rest of FlightGear is.
makes more sense to keep I/O running. That way remote telnet connections
will still respond, and the sim can still accept and send data. This also
allows a remote script or gui to pause and (more importantly) be able to
the unpause the sim.
This patch is there to correct a problem that prevent to load static objects when specifying a relative fg-root or a different, relative, fg-scenery. It appears that there is a mix between fg-root, fg-scenery and PLIB's model-dir.
It has been reported on the list that users are not able to see the buildings, especially those running the win32 builds because they run 'runfgfs.bat' that set FG_ROOT=./DATA.
I decided not to use model-dir because it just add confusion and to build a valid path earlier.
I have added a fledgling replay system that records flight data and control
positions during the flight.
I have added an internal command called "replay" which will trigger a replay
of the entire saved flight data set. This could be bound to a keyboard or
menu command, in fact this entire module is screaming for someone to build
a gui to control playback speed, amount of playback, etc.
This is the initial version so there are kinks that still need to be worked
out, please be patient.
/sim/rendering/horizon-effect
toggle sun and moon resizing effect near the horizon
/sim/rendering/enhanced-lighting
toggle enhanced runway lighting on or off
/sim/rendering/distance-attenuation
add distance attenuation to the enhanced runway lighting
etc.
Improved the weather system to interpolate between different
elevations and deal with boundary-layer conditions. The configuration
properties are now different (see $FG_ROOT/preferences.xml).
Normally for smoothest frame rates you would configure to sync
to your monitor's vertical refresh signal. This is card/platform
dependent ... for instance with Linux/Nvidia there is
an environment variable you can set to enable this feature.
However, if your monitor is refreshing at 60hz and you can't quite sustain
that with flightgear, you can get smoother frame rates by artificially
throttling yourself to 30hz. Note that once you are about about 24fps, it
is *change* or inconsistancy in frame rate that leads to percieved jerkiness.
You want to do whole divisors of your monitor refresh rate, so if your
display is syncing at 75 hz, you might want to try throttling to 25 hz.
Melchior FRANZ:
The reason: these models are to be added to the scenery, but the
scenery isn't yet set up at this point. The correct order is:
- set up model_lib (needed by the scenery)
- set up scenery (needed by the model manager)
- set up model manager
the ascii scenery file format has actually worked in quite some time, and the
ADA runway light code has been supersceded by a slightly different mechanism.
scene management code and organizing it within simgear. My strategy is
to identify the code I want to move, and break it's direct flightgear
dependencies. Then it will be free to move over into the simgear package.
- Moved some property specific code into simgear/props/
- Split out the condition code from fgfs/src/Main/fg_props and put it
in it's own source file in simgear/props/
- Created a scene subdirectory for scenery, model, and material property
related code.
- Moved location.[ch]xx into simgear/scene/model/
- The location and condition code had dependencies on flightgear's global
state (all the globals-> stuff, the flightgear property tree, etc.) SimGear
code can't depend on it so that data has to be passed as parameters to the
functions/methods/constructors.
- This need to pass data as function parameters had a dramatic cascading
effect throughout the FlightGear code.
The one to fg_init.cxx initialises the AI subsystem regardless of whether it's enabled or not so that later enabling by the user doesn't crash it, and the one to main.cxx avoids running the ATC manager and ATC display system unless enabled.
This is just a port of an old 3D HUD patch to the new view code.
This pans the HUD with the view, by pasting it onto a quad fixed in front of the viewer. It also fixes the awful, arbitrary scaling problems the HUD code has. The old HUD only looks right when viewed at 1024x768 and 55 degree FOV. This works the scale out magically so that it looks right in all views. It also redefines the "<compression-factor>" tag in the ladder to (1) mean compression instead of expansion and (2) have non-psychopathic units (now "1" means 1 degree per degree). Fix this in your existing HUD ladder files before reporting bugs. It's definitely a cosmetic win -- the velocity vector points at the right thing and the horizon lines up properly.
Norman wrote:
I have created a modified version of Andy's patch that implements the 3D HUD as the 'normal' and the 2D HUD as the 'minimal' HUD. < i > and < shift I > keys
Some more cmall changes to the SimGear header files and removed the
SG_HAVE_NATIVE_SGI_COMPILERS dependancies from FlightGear.
I've added a seperate JSBSim patch for the JSBSim source tree.
experimental lighting rendering (which is very expensive on my
machine, for example). To use distance attenuation,
/sim/rendering/distance-attenuation must also be true.
It adds a command line options to enable/disbale distance attenuation
using a property rather than using a #define inside the code. It also
adds a small change for systems that don't support the OpenGL extension,
so that the lights *do* fade away as they get furher away but they don't
get smaller in size.
I have updated the lighting code to use fog to try to fade the runway lights
in smoothly, but still keep them from being visible until you are about 7-10
miles out, and then only have them be very faint at first. I think what I
have is a bit nicer than before since it completely avoids the "popping" effect,
but I've very open to tweaking the actual ranges based on people's real
world experiences.
The general idea is to help clean up some aspects of the FDM init and be
able to provide startup conditions in a less ambiguous manner.
Previously, things like positions, orientations, and velocites were set on
"the bus". These had to be read by the FDMs which then were supposed to
initialized themselves to those values and turn write around and start
modifying those values. It was messy and cumbersome.
Now, all the initial fdm conditions are written to a sub-[property-]tree
under /sim/presets/
The values in /sim/presets/ always stay set to what the user has specified.
The user can change these at his/her liesure, and then request a "reset"
which will reset to the new conditions. I don't even want to say how this
worked before. :-)
Now, an script, or gui interface can stage a set of initial conditions while
the sim is running (without disrupting it), and then call "reset" to commit
the change.
People who should worry about all this are FDM writters, and a small few
others who care about over all program structure and flow.
The biggest and coolest patch adds mouse sensitivity to the 3D
cockpits, so we can finally work the radios. This ended up requiring
significant modifications outside of the 3D cockpit code. Stuff folks
will want to look at:
+ The list of all "3D" cockpits is stored statically in the
panelnode.cxx file. This is clumsy, and won't migrate well to a
multiple-aircraft feature. Really, there should be a per-model list
of 3D panels, but I couldn't find a clean place to put this. The
only handle you get back after parsing a model is a generic ssg
node, to which I obviously can't add panel-specific methods.
+ The aircraft model is parsed *very* early in the initialization
order. Earlier, in fact, than the static list of allowable command
bindings is built in fgInitCommands(). This is bad, as it means
that mouse bindings on the instruments can't work yet. I moved the
call to fgInitCommands, but someone should look carefully to see
that I picked the right place. There's a lot of initialization
code, and I got a little lost in there... :)
+ I added yet another "update" hook to the fgRenderFrame routine to
hook the updates for the 3D panels. This is only required for
"mouse press delay", and it's a fairly clumsy mechanism based on
frame rate instead of real time. There appears to be delay handling
already in place in the Input stuff, and there's a discussion going
on about different mouse behavior right now. Maybe this is a good
time to unify these two (now three) approaches?
Now the options can be localized as well. This adds a slight problem for
the --language options, but not that much (worst case, the strings are
loaded twice consuming some more memory). I tried to be as accurate as
posiible when copying the options texts, but there might be some
mostakes left.
This adds supports for a language specific font, defined in locale.xml
I've also moved the fgInitLocale() routine from main.cxx to fg_init.cxx
to prevent an ungly extern definition in options.cxx.
are now working. A runway light is defined by a point and a direction. The
point and direction are combined with the local up vector to create a small
triangle orthogonal to the direction. The two ficticous corners of the
triangle are given an alpha value of zero, the orignal corner is given an
alpha of one. The triangle is drawn in glPolygonMode(GL_FRONT, GL_POINT)
mode which means only the corner points are drawn, and since two have alpha=0
only the original point is drawn. This is a long way to go to draw a point,
but it ensures that the point is only visible within 90 degrees of the light
direction, behind the light it is not visible. This is still a long way
to get to drawing a point, but we use an environement map, with the direction
vector as the normal to mimic a light that is brightest when viewed head
on and dimmest when viewed perpendicularly or disappears when viewed from
behind.
- warning, there is a bug in how the current runway light direction vector
is calculated which will adversely effect runway lighting. The airports
should be regenerated in order to fix this problem.
This patch fixes some bugs for correctly reporting un-updated
configuration files, and adds support for a --language=<code>
commandline option, overriding the language specified by the OS.
jump whenever you cross a tile, but there are currently a lot of other
positioning problems as well, so this doesn't really detract too much and
means you can play with 3d clouds from just about any starting point.
I removed some pending random code and I also fixed a
small cosmetic glitch where dt_play was cleared before it was printed.
Curt: Erik changed the sound update intervale and I further I tweaked it.
The issue is that if we put too much into the sound buffer, then we can't react
quick enough to sounds like tire squeek that need to be synced with the visuals
and the action. We put too little into the sound buffer and we risk the
audio dropping out for moment if a frame takes longer to draw than the amount
of audio in the buffer.
Here is a FGIO class derived from FGSubsystem that replaces the fgIOInit()
and fgIOProcess() functions. The FGIO::update(double delta) doesn't use the
delta argument yet. I suspect it could be used as a replacement for the
calculated interval value but I'm not familiar enough with that piece of code
just yet.
I've also added two "command properties" to fg_commands.cxx that select the
next or previous view. Writing any value to these properties triggers the
corresponding action. As an example I modified my keyboard.xml:
<key n="118">
<name>v</name>
<desc>Next view</desc>
<binding>
<command>property-assign</command>
<property>/command/view/next</property>
<value type="bool">true</value>
</binding>
</key>
<key n="86">
<name>V</name>
<desc>Prev view</desc>
<binding>
<command>property-assign</command>
<property>/command/view/prev</property>
<value type="bool">true</value>
</binding>
</key>
And of course these actions can also be triggered from external scripts via
the props server.
Animations are now contained within the scene graph itself and are
updated whenever the graph is traversed -- that saves time by not
updating animations not currently in sight, and it allows animations
to be used for static objects and random objects as well.
Added new FGModelLoader and FGTextureLoader classes. These are intern
tables for models, to guarantee (mostly) that no model is loaded more
than once. FGTextureLoader is not yet used anywhere, but
FGModelLoader is now in place everywhere that ssgLoad* used to be
used (thus adding the ability to use animations).
In the future, FGModelLoader will add some interesting functionality,
including the ability to reload 3D models on the fly.
the triangles containing the objects were out of the view Frustum,
they were never traversed by ssg (and thus, never culled). Now, every
200 frames, do a pass through the whole scene graph with cull-testing
disabled and without drawing anything; that will allow random-objects
to be collected incrementally.
This is a small fix for what turned out to be a major bug. Ground elevation
was calculated incorrectly when distant from one of the view locations. This
resulted in several problems including bizarre gear trimming, mid air
"crashes" (as in thinking we hit the ground) and so on when close to or on the
ground.
Unfortunately it does require a second ssg traversal when in tower view
(only), but the increased load isn't all that noticable. For the time being
this really is the best solution. In a future update I will be eliminating
the unecessary per frame traversals for the static views (without having to
maintain multiple ssgRoots).
When we go to multiple FDM instances we will perhaps need to put the ssg
traversal and ground elevation queries for the FDMs into an event timer that
updates the FDMs ground elevation in a round robin fashion (maybe every 1/n
seconds where n is the number of FDM instances running).
This is a new improved patch for the previous tile manager fixes.
Rather than building dependencies between FGlocation or the viewer or fdm with
tilemgr what I ended up doing was linking the pieces together in the Mainloop
in main.cxx. You'll see what I mean...it's been commented fairly well. More
than likely we should move that chunk somewhere...just not sure where yet.
The changes seem clean now. As I get more ideas there could be some further
improvement in organizing the update in tilemgr. You'll note that I left an
override in there for the tilemgr::update() function to preserve earlier
functionality if someone needs it (e.g. usage independent of an fdm or
viewer), not to mention there are a few places in flightgear that call it
directly that have not been changed to the new interface (and may not need to be).
The code has been optimized to avoid duplicate traversals and seems to run
generally quite well. Note that there can be a short delay reloading tiles
that have been dropped from static views. We could call the tile scheduler on
a view switch, but it's not a big deal and at the moment I'd like to get this
in so people can try it and comment on it as it is.
Everything has been resycned with CVS tonight and I've included the
description submitted earlier (below).
Best,
Jim
Changes synced with CVS approx 20:30EDT 2002-05-09 (after this evenings updates).
Files:
http://www.spiderbark.com/fgfs/viewer-update-20020516.tar.gz
or
http://www.spiderbark.com/fgfs/viewer-update-20020516.diffs.gz
Description:
In a nutshell, these patches begin to take what was one value for ground
elevation and calculate ground elevation values seperately for the FDM and the
viewer (eye position). Several outstanding view related bugs have been fixed.
With the introduction of the new viewer code a lot of that Flight Gear code
broke related to use of a global variable called "scenery.cur_elev".
Therefore the ground_elevation and other associated items (like the current
tile bucket) is maintained per FDM instance and per View. Each of these has a
"point" or location that can be identified. See changes to FGLocation class
and main.cxx.
Most of the problems related to the new viewer in terms of sky, ground and
runway lights, and tower views are fixed.
There are four minor problems remaining. 1) The sun/moon spins when you pan
the "lookat" tower view only (view #3). 2) Under stress (esp. magic carpet
full speed with max visibility), there is a memory leak in the tile caching
that was not introduced with these changes. 3) I have not tested these
changes or made corrections to the ADA or External FDM interfaces. 4) The
change view function doesn't call the time/light update (not a problem unless
a tower is very far away).
Details:
FDM/flight.cxx, flight.hxx - FGInterface ties to FGAircraftModel so that it's
location data can be accessed for runway (ground elevation under aircraft)
elevation.
FDM/larsim.cxx, larcsim.hxx - gets runway elevation from FGInterface now.
Commented out function that is causing a namespace conflict, hasn't been
called with recent code anyway.
FDM/JSBSim/JSBSim.cxx, YASim/YASim.cxx - gets runway elevation from
FGInterface now.
Scenery/newcache.cxx, newcache.hxx - changed caching scheme to time based
(oldest tiles discard).
Scenery/tileentry.cxx, tileentry.hxx - added place to record time, changed
rendering to reference viewer altitude in order to fix a problem with ground
and runway lights.
Scenery/tilemgr.cxx, tilemgr.hxx - Modified update() to accept values for
multiple locations. Refresh function added in order to periodically make
the tiles current for a non-moving view (like a tower).
Main/fg_init.cxx - register event for making tiles current in a non-moving
view (like a tower).
Main/location.hxx - added support for current ground elevation data.
Main/main.cxx - added second tilemgr call for fdm, fixed places where viewer
position data was required for correct sky rendering.
Main/options.cxx - fixed segfault reported by Curtis when using --view-offset
command line parameter.
Main/viewer.cxx, viewer.hxx - removed fudging of view position. Fixed numerous
bugs that were causing eye and target values to get mixed up.
Here is the new super improved telnet property interface. CVS changelog
is at the end of this message. Once this new telnet code is in and
compiles every where we can remove Network/props.[ch]xx. I've added a
--telnet=<port> command line option to invoke the new server. Later on
we could remove the --props option, or least change it to invoke the new
server. I'll let you decide.
I've added some new commands to the telnet interface:
view next Select the next view.
view prev Select the previous view.
view set <n> Select view 'n'
view get Return index of current view
I'm not sure if these same effects could be achieved through property
operations. The commands provide a convenient shortcut in any case.
I'm also planning on adding a panel command to manipulate panels and
objects contained therein (eg simulated mouse clicks). There is going
to be some commonality with the command objects so we may need to
rationalize this in the near future.
Finally, I've also included my python stuff. This is still very much a
work in progress, basically I've been using it to test the new telnet
server. I have tested it with python 2.2. Feel free to add it to the
repository if you want. I would suggest a scripts/python directory
CVS Changelog
Network/telnet.cxx: New property telnet protocol interface. It supports
the same user interface provided by the --props server. Additionally it
handles multiple simultaneous connections. Added "view" command to
manipulate viewmgr.
Network/protocol.hxx: Added protocol configuration exception.
Main/fg_io.cxx: Added new "telnet" protocol. Added protocol
configuration parse exceptions. Simplified protocol configuration
parsing.
Main/options.cxx: Added --telnet=<port> command line option and help
message.
Removed configuration option --with-new-environment and
FG_NEW_ENVIRONMENT macro.
Added configuration option --with-weathercm and FG_WEATHERCM macro.
FGEnvironment is now the default; use --with-weathercm to get the old
weather.
- changed FGSubsystem::update(int) to
FGSubsystem::update(delta_time_sec); the argument is now delta time
in seconds rather than milliseconds
- added FGSubsystem::suspend(), FGSubsystem::suspend(bool),
FGSubsystem::resume(), and FGSubsystem::is_suspended(), all with
default implementations; is_suspended takes account of the master
freeze as well as the subsystem's individual suspended state
- the FDMs now use the delta time argument the same as the rest of
FlightGear; formerly, main.cxx made a special case and passed a
multiloop argument
- FDMs now calculate multiloop internally instead of relying on
main.cxx
There are probably some problems -- I've done basic testing with the
major FDMs and subsystems, but we'll probably need a few weeks to
sniff out bugs.
1. If /position/longitude-deg and /position/latitude-deg are in range,
use them.
2. Otherwise, if /sim/startup/airport-id is not empty, use it.
3. Otherwise, set the lon/lat to the middle of the KSFO field.
The default used to be Globe, AZ, but that doesn't make sense since we
don't distribute that scenery by default any more.
With this change, starting from a save file seems to work properly:
fgfs myflight.sav
SGTimeStamp "-" operator returns it's result in usec's, there is an upper bound of 37.8 minutes on the maximum difference this operator can reliably report
before the math overflows. I change the global "int elapsed_time_ms" variable
to a "double sim_time_ms" and restructured how the value is calculated.
----
The practical result of the overflow bug is that a large negative dt was
passed to the event manager and the end effect was that no events would
be run until their counters caught up ... in another 37.8 minutes or so.
These are the updates for the View manager properties. Removed the last of
items (within the viewer/viewmgr) hard coded to view number. Added support
for per view configuration of ground level nearplane value. Tower views look
very nice with little or no z-buffer problem in the models. Pilot offset
dialog can be used to move eye in all views.
graph as the terrain, except for internal cockpit view. The SSG
scene-graph variables (except for the lighting root -- I'll get that
later) are now held in globals.hxx.
FGModelMgr::draw() is obsolete; I'll remove it in a future revision.
Synced to CVS 19:36 EDT 2002-04-10 (after this evenings JSMsim and Base
package updates).
Description:
Added FGLocation class which is new home for calculating matrix rotations.
Viewer can now be configured to access rotations created by the model rather
than repeating the same calculations again.
Changed model initialization for the time being so that its location data is
available for the viewer (currently required by other subsystems). At some
point we can move this back to fg_init along with the viewer initialization.
Seperated the update from the draw function in the model code. The viewer
code needs the same matrix data, and moving the update portion at this time
does not increase the number of matrix math iterations.
Moved the model draw so that it always appears "in front" of lights and clouds.
Reogranized viewer update routine for using the FGLocation class and
simplified some more tasks. The routine is fairly easy to follow now, with
the steps ordered and spelled out in comments.
Viewmgr only updates the current (visible) view now, with the exception of an
old reference to "chase view" that will be corrected in forthcoming changes.
Also will be doing some work on the viewmgr outputs.
Model is now clears the z-buffer in all modes. This will be changed with the
next viewmgr update. The only side effect is that models always disappear
when over 5km distant from the eye point (can't really see them anyway:-)).
Other than a flag to indicate "internal" view I don't anticipate the
configuration interface for viewmgr/views will be changed a lot for now. It
is close to done. The next viewmgr update will however rework the outputs so
may change location.
This code will run with the previous version of preferences.xml, but will run
faster with the newer version. I am attaching a preferences.xml that should
not be commited before the code. All the changes are in the /sim/view section
and should show a simpler view configuration that references model locations.
Note that I've added a 2nd tower view in "lookfrom" mode for illustration
purposes. You can look around using the mouse. You may want to remove that or
comment it out.
Minor patches to initial tower view code. Added calculation for "tower" at
any airport, placed a couple fractions of a degree off the center. Moved the
farplane from 100m to 5km so that "lookfrom" mode can see the model. 5km is
still in a reasonable range for a depth buffer. Note that looking at a model
anything but a small distance will cause some problems on older cards.
Temporarily changed viewer to always report elevation/lon/lat of the aircraft
in order to avoid a problem with the ground trim getting recalculated when
tower and aircraft are on different tiles.
radiostack.cxx, fg_init.cxx and main.cxx. If these changes are accepted
then you can remove Time/event.[ch]xx and Include/fg_callback.hxx from
the repository.
Tower View and viewer config is in place. Note that the interface is
still in a state of flux. A couple of the config items (namely the
offsets) are still using the old settings. The tower is hard coded
into the base package for a position off the starting runway at KSFO
and is probably not in the right place for there even. Looks pretty
cool though! Tower View is the third view. If you aren't at KSFO
you'll just see blank space in view 3. It's looking through the earth or
something like that :-). Important note: zoom in with a few
hits of the "x" key to see the plane better in tower view.
case logging is disabled). This way, when people specify a
non-existant aircraft or have an error in a custom XML file, they'll
get an error report, at least.
system. A chap from Germany called Alexander Kappes (cc'd) got
in touch with me a few weeks ago and has written the start of
Approach control. At the moment tuning in to a valid approach
frequency (Dortmund or East Midlands) should result in vectors to
a spot about 3 miles from the active runway, and a telling off if you
stray too far from the correct course, in the console window. He
seems to know what he's doing so expect this to improve rapidly!!
I've added a rudimentry AI manager and a hardwired Cessna at
KEMT on the runway - I'll remove it before the next release if I don't
have it flying by then. There seems to be an issue with framerate
which drops alarmingly when looking at it - I've a feeling that I've
possibly created several Cessnas on top of each other, but am not
sure.
Clear frame buffer and render model after rest of 3D scene. This has a
small frame rate cost (YMV). But who thought 3D cockpit would be cheap?
If anyone has a better idea, have at it!
Just did some more careful testing and I see little or no frame rate loss
with the depth buffer clear. Also you can change the near plane to 0.1
and get rid of the "sunroof" (so I don't have to make up another set of
patches.
This patch creates a seperate scene graph for the cockpit. The near plane is
only moved up when in the interior (pilot) view. This is because with
rounding (I presume) it the visible ground is a bit up higher than it is with
the older nearplane setting. Not much, but it is enough to bury the wheels.
I suspected this might be true but spliting to two sg's confirms it. If
necessary we can adjust the model up a bit when in interior view. This might
be good so we can set the near plane even closer when in the cockpit (its
still at 0.2m).
In general this looks a lot better on my Voodoo with this patch. No
perceptibel change in frame rate on my system. In terms of future plans I'd
see the sense in making the model plug into either scene. This will be
necessary when we have multiple model instances in the frame.
(mainly in src/Input/input.cxx) will make src/GUI/mouse.cxx obsolete
and bring the mouse into the same input system as the joystick and
keyboard. This is just preliminary work allowing, covering mouse
clicks (no motion yet), and it actually crashes on a middle or right
click.
The new mouse support is disabled by default until it become stable;
to try it out, you need to configure --with-new-mouse.
interface instead of string. This will result in a lot more
efficiency later, once I add in a simple hash table for caching
lookups, since it will avoid creating a lot of temporary string
objects. The major considerations for users will be that they cannot
use
node->getName() == "foo";
any more, and will have to use c_str() when setting a string value
from a C++ string.
separate header file. This change will help integrate properties into
JSBSim.
Also, I (David Megginson) removed most of the SimGear include
statements from globals.hxx, reducing the amount of recompilation
every time SimGear changes. This required making minor changes to a
lot of files that were depending on the side-effects of the inclusions
in globals.hxx.
- implement the standard FGSubsystem interface, for consistency
- eliminate current_autopilot and add get/set_autopilot to FGGlobals,
for consistency
- use private methods rather than static functions for tying
properties
There should be no change in functionality.
plane to 0.2; otherwise, use the old defaults.
This is a temporary step that will allow me to work on a 3D cockpit
without breaking current behaviour; the final approach will be to put
the 3D model in its own scene graph, with different clipping plane.
to 10m after takeoff, but that doesn't really make sense any more,
especially if models are going to have interior views. Is there any
real saving in pushing the near plane out anyway?
What the attached patch does is map your panel definition onto a (non
z-buffered) quad in front of your face. You can twist the view around
and see it move in the appropriate ways.
Apply the patch (let me know if folks need help with that step), and
then set the /sim/virtual-cockpit property to true. You can do this
on the command line with --prop:/sim/virtual-cockpit=1, or via the
property picker. Bind it to a key for fast toggling if you like.
The default bindings don't allow for "panning" the view, so you'll
have to modify yours. These are the mappings to my joystick's hat
switch, for those who need hints:
<axis n="6">
<desc>View Direction</desc>
<low>
<repeatable>true</repeatable>
<binding>
<command>property-adjust</command>
<property>/sim/view/goal-offset-deg</property>
<step type="double">1.0</step>
</binding>
</low>
<high>
<repeatable>true</repeatable>
<binding>
<command>property-adjust</command>
<property>/sim/view/goal-offset-deg</property>
<step type="double">-1.0</step>
</binding>
</high>
</axis>
<axis n="7">
<desc>View Elevation</desc>
<low>
<repeatable>true</repeatable>
<binding>
<command>property-adjust</command>
<property>/sim/view/goal-tilt-deg</property>
<step type="double">1.0</step>
</binding>
</low>
<high>
<repeatable>true</repeatable>
<binding>
<command>property-adjust</command>
<property>/sim/view/goal-tilt-deg</property>
<step type="double">-1.0</step>
</binding>
</high>
</axis>
While the current implementation is happy with just plastering the
panel's notion of "screen" into the 3D world, this is actually more
general. Each panel can, in principle, have it's own coordinate
system, and you could build a cockpit out of a bunch of them. The
mapping is specified by providing a 3D coordinate for three corners of
the quad the panel should be mapped to; this should be pretty simple
to work with.
All that's needed for a perfectly general solution is a convention on
where to store the information (a cockpit xml file, or put it in the
aircraft -set file, or...), and some work on the panel's coordinate
system conventions (some of which don't coexist very nicely with a
generalized 3D environment). Combine that with a plib model for the
non-panel interior of the cockpit, and we're golden.
I'm actually really pleased with this. It worked better and more
quickly than I could have imagined, and impact on the surrounding code
is quite light -- a few property tests only. But some stuff is still
missing:
+ No equivalent work was done to the HUD, so it still displays
incorrect headings when the view changes. The use of pixel
coordinates deep in the HUD code is going to give me fits doing the
port, I sure. It's not nearly so well put together as the panel
(where I just changed the setup code -- none of the rendering code
changed at all).
+ I forgot that the panel was clickable. :) Input events still have
the screen coordinates, which essentially kills the interactivity
when in virtual cockpit mode. This won't be hard to fix; it's only
broken because I forgot the feature existed.
And one note about the implementation choice: to get away from the
inevitable near clip plane issue, the virtual cockpit renderer simply
disables the z buffer. This means that cockpits built using these
panels need to be z-sorted, which isn't too hard since they are static
geometry. It also means that no two "virtual panels" can ever be
allowed to interpenetrate. No biggie.
subsystem to Flightgear. No more functionality is implemented
than at present (apart from an ATIS bug-fix - station wouldn't
change if the radio was switched directly from one station to
another) but it is much neater than the current hack and should be
easily extendable.
Some cruft is still probably left over in radiostack.[ch]xx such as
the bindings to the comm frequencies but I'll leave removing those
until I'm sure they're not needed there.
individual aircraft to have different sounds (and cleaning up my code
a fair bit). The most important user-visible change is the renaming
of the /sim/sound property to /sim/sound/audible.
different locations, and hitched it into FGGlobals. FGEnvironmentMgr
has taken over as the subsystem, while FGEnvironment is simple the
information that it returns. I've removed current_environment
completely -- everything now uses properties or goes through
FGGlobals. FGGlobals itself has a couple of useful methods:
const FGEnvironment * get_environment ();
const FGEnvironment * get_environment (double lat, double lon, double alt);
The first one returns the environment data for the plane's current
position, while the second returns the environment data for any
arbitrary location. Currently, they both return the same information,
but that will change soon.
properties have been renamed from wind-(north|east|down)-fps to
wind-from-(north|east|down)-fps, and the FDMs modified appropriately.
No other changes should be visible unless FG_OLD_WEATHER is defined.
via the command line (--enable-clock-freeze / --disable-clock-freeze)
and can be toggled during a run. However this property is not currently
bound to any menu or keystroke so you have to do it via the gui property
interface or externally via the web property browser or a script.
max(width, height) by default (easily changeable) rather than just width.
(src/GUI/gui.cxx, src/Main/main.cxx, src/Main/viewer.cxx, src/Main/viewer.hxx)
This works on a CygWin build, and probably works on non-Cygwin builds
as well.
2. Enable FG to start even if audio is not available. (soundmgr.cxx)
Avoids the FGSoundMgr constructor crashing; the rest of FG then runs
OK without sound.
1. Enable auto-configure on more versions of auto tools. (configure.in)
2. Warnings from auto-configure tools. (src/Time/Makefile.am)
3. Typo: "the it's" -> "its". (docs-mini/README.Joystick)
4. Remove definition of FGViewer::update() that now is (or can be) pure
virtual\
. (src/Main/viewer.cxx)
5. Preferred form of function name according to comments in plib:
"not_working"\
-> "notWorking". (src/Sound/soundmgr.hxx)
/sim/freeze/master (implimented)
/sim/freeze/fuel (implimented)
/sim/freeze/position (not implimented)
/sim/freeze/time-of-day (not implimented)
/sim/freeze/master is bound to the 'p' key via keyboard.xml, however,
/sim/freeze/fuel is not bound to anything at the moment so you must
change it via the external property interface, or specify an initial
value on the command line.
beginning of main() for the exceptions that can be enabled (only
divide-by-zero is enabled by default, but you can uncomment any ones
you want); eventually, FlightGear should run cleanly with all FPEs
enabled.
(i.e. multiloop). Most subsystems currently ignore the parameter, but
eventually, it will allow all subsystems to update by time rather than
by framerate.
fix startup sequence problems where we initialize the FDM before we know
the desired starting altitude.
These changes delay fdm initialization until the local tile has been loaded
and we can do a real intersection and find the true ground elevation.
In order to do this, I depend more on the property manager as glue, rather
than the FGInterface.
There are some glitches still when switching to a new airport or reseting
the sim. I will work on addressing these, but I need to commit the changes
so far to keep in sync with other developers.
meaning of "win_ratio". I've removed win_ratio and added fov_ratio and
aspect_ratio, as it seems both are needed.
n.b. The multi-line changes in fgReshape comprise:
extracting common code,
removing an apparently arbitrary "+1" on the view height,
changing "set_win_ratio" to "set_aspect_ratio".
