[Flightgear-devel] scenery appearance depends on camera tilt angle
What steps will reproduce the problem? --lat=37.637855 --lon=-122.414915 --altitude=656 --heading=113 --fdm=ufo aircraft is stopped. zero airspeed, zero rate of turn, etc. The choice of aircraft doesn't seem to matter; this is 100% reproducible chez moi using the default c172p, the pa24-250, et cetera. Zoom in the view; FoV 15.5 will do; 12.5 is better; 7.7 is even better, if you have good control of the pitch/tilt and view angle. Change the view angle, either by pitching the entire aircraft or by simply tilting the pilot's view angle relative to the aircraft. What is the expected output? Scenery should not change. The ray from each object to the camera image plane should stay the same, except to move to a different point in the image plane, when the camera is tilted. What do you see instead? For some tilt angles, the taxiway signs alongside taxiway charlie are dark, while at other title angles they are lit. http://www.av8n.com/fly/fgfs/img48/taxi-signs-off.png http://www.av8n.com/fly/fgfs/img48/taxi-signs-on.png I cannot imagine what could be causing this. == The same phenomenon is seen during normal flight, but is harder to reproduce and document. -- Download Intel® Parallel Studio Eval Try the new software tools for yourself. Speed compiling, find bugs proactively, and fine-tune applications for parallel performance. See why Intel Parallel Studio got high marks during beta. http://p.sf.net/sfu/intel-sw-dev ___ Flightgear-devel mailing list Flightgear-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/flightgear-devel
Re: [Flightgear-devel] scenery appearance depends on camera tilt angle
> What steps will reproduce the > problem? > > --lat=37.637855 --lon=-122.414915 --altitude=656 > --heading=113 --fdm=ufo > > aircraft is stopped. zero airspeed, zero rate of > turn, etc. > > The choice of aircraft doesn't seem to matter; this > is 100% > reproducible chez moi using the default c172p, the > pa24-250, > et cetera. > > Zoom in the view; FoV 15.5 will do; 12.5 is better; > 7.7 is > even better, if you have good control of the pitch/tilt and > > view angle. > > Change the view angle, either by pitching the entire > aircraft > or by simply tilting the pilot's view angle relative to > the > aircraft. > > What is the expected output? > > Scenery should not change. The ray from each object > to the > camera image plane should stay the same, except to move to > a different point in the image plane, when the camera is > tilted. > > What do you see instead? > > For some tilt angles, the taxiway signs alongside taxiway > charlie are dark, while at other title angles they are > lit. > http://www.av8n.com/fly/fgfs/img48/taxi-signs-off.png > http://www.av8n.com/fly/fgfs/img48/taxi-signs-on.png > > I cannot imagine what could be causing this. > > == > > The same phenomenon is seen during normal flight, but is > harder to reproduce and document. Wel,, I would see this as a bug, if the frontside with the letter can't be read then anymore. But your pics shows it can bes till, it is just the backside which changes the color. Not a serious bug or showstopper for __ Do You Yahoo!? Sie sind Spam leid? Yahoo! Mail verfügt über einen herausragenden Schutz gegen Massenmails. http://mail.yahoo.com -- Download Intel® Parallel Studio Eval Try the new software tools for yourself. Speed compiling, find bugs proactively, and fine-tune applications for parallel performance. See why Intel Parallel Studio got high marks during beta. http://p.sf.net/sfu/intel-sw-dev ___ Flightgear-devel mailing list Flightgear-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/flightgear-devel
Re: [Flightgear-devel] scenery appearance depends on camera tilt angle
On Thu, Mar 11, 2010 at 4:47 PM, Heiko Schulz wrote: > Wel,, I would see this as a bug, if the frontside with the letter can't be > read then anymore. But your pics shows it can bes till, it is just the > backside which changes the color. > > Not a serious bug or showstopper for FWIW, when I'm flying, I see the shading on the scenery change drastically during the flight as the plane turns and pitches. I think what's happened is instead of just changing the shading on the panel, we're changing the shading on the scenery too. FGFS didn't used to do that, so it's a relatively recent introduction. All the best, David -- Download Intel® Parallel Studio Eval Try the new software tools for yourself. Speed compiling, find bugs proactively, and fine-tune applications for parallel performance. See why Intel Parallel Studio got high marks during beta. http://p.sf.net/sfu/intel-sw-dev ___ Flightgear-devel mailing list Flightgear-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/flightgear-devel
Re: [Flightgear-devel] scenery appearance depends on camera tilt angle
Hi, > > FWIW, when I'm flying, I see the shading on the scenery > change > drastically during the flight as the plane turns and > pitches. I think > what's happened is instead of just changing the shading on > the panel, > we're changing the shading on the scenery too. FGFS > didn't used to do > that, so it's a relatively recent introduction. > > > All the best, > > > David > Now I understand- the whole scenery! (But THIS John never mentioned) And he had should wrote, that shaders are disabled. That's the cause of the bug I guess- when shaders disabled the shading is changed. That's something really noticeable above the sea or a lake. And yes, as we offer FGFS for using without shaders as well, it is a bug. Heiko __ Do You Yahoo!? Sie sind Spam leid? Yahoo! Mail verfügt über einen herausragenden Schutz gegen Massenmails. http://mail.yahoo.com -- Download Intel® Parallel Studio Eval Try the new software tools for yourself. Speed compiling, find bugs proactively, and fine-tune applications for parallel performance. See why Intel Parallel Studio got high marks during beta. http://p.sf.net/sfu/intel-sw-dev ___ Flightgear-devel mailing list Flightgear-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/flightgear-devel
Re: [Flightgear-devel] scenery appearance depends on camera tilt angle
On Thu, Mar 11, 2010 at 10:26 PM, John Denker wrote: ... > > Change the view angle, either by pitching the entire aircraft > or by simply tilting the pilot's view angle relative to the > aircraft. > > What is the expected output? > > Scenery should not change. The ray from each object to the > camera image plane should stay the same, except to move to > a different point in the image plane, when the camera is > tilted. > > What do you see instead? > > For some tilt angles, the taxiway signs alongside taxiway > charlie are dark, while at other title angles they are > lit. > http://www.av8n.com/fly/fgfs/img48/taxi-signs-off.png > http://www.av8n.com/fly/fgfs/img48/taxi-signs-on.png > > I cannot imagine what could be causing this. > > The mesh representing the back of a sign is not complete; graphics state from other parts of the scenery are leaking into it. The particular effect depends on the global draw order, which does change as your viewing angle changes. I don't know why this ever worked. What color are the sign backs supposed to be? Tim -- Download Intel® Parallel Studio Eval Try the new software tools for yourself. Speed compiling, find bugs proactively, and fine-tune applications for parallel performance. See why Intel Parallel Studio got high marks during beta. http://p.sf.net/sfu/intel-sw-dev___ Flightgear-devel mailing list Flightgear-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/flightgear-devel
Re: [Flightgear-devel] scenery appearance depends on camera tilt angle
On Thu, Mar 11, 2010 at 10:26 PM, John Denker wrote: > > For some tilt angles, the taxiway signs alongside taxiway > charlie are dark, while at other title angles they are > lit. Not that it matters but I have reported this issue already: http://www.mail-archive.com/flightgear-devel@lists.sourceforge.net/msg25180.html Okay so maybe the bug tracker is a good idea :) -- Csaba/Jester -- Download Intel® Parallel Studio Eval Try the new software tools for yourself. Speed compiling, find bugs proactively, and fine-tune applications for parallel performance. See why Intel Parallel Studio got high marks during beta. http://p.sf.net/sfu/intel-sw-dev ___ Flightgear-devel mailing list Flightgear-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/flightgear-devel
Re: [Flightgear-devel] scenery appearance depends on camera tilt angle
On 03/11/2010 03:15 PM, Tim Moore wrote: > The mesh representing the back of a sign is not complete; graphics state > from other parts of the scenery are leaking into it. The particular effect > depends on the global draw order, which does change as your viewing angle > changes. Thanks for the rapid and informative explanation. > What color are the sign backs supposed to be? Unless the back of the sign has something to say, it's nondescript gray or black. Here are some examples: http://cdn-www.airliners.net/aviation-photos/photos/4/4/9/0777944.jpg However, double-sided signs are common. Every one of the signs in this diagram is double-sided: http://www.aopa.org/images/asf/pubs/sa07/p4-9.gif For the next level of detail on this, see the parent page: http://www.aopa.org/asf/publications/taxi/taxi_signage.html Here's one that is partially blank/black because whatever it says on the other side is longer: http://farm1.static.flickr.com/171/456566291_270613d348.jpg -- Download Intel® Parallel Studio Eval Try the new software tools for yourself. Speed compiling, find bugs proactively, and fine-tune applications for parallel performance. See why Intel Parallel Studio got high marks during beta. http://p.sf.net/sfu/intel-sw-dev ___ Flightgear-devel mailing list Flightgear-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/flightgear-devel
Re: [Flightgear-devel] scenery appearance depends on camera tilt angle
I've checked in a fix for the sign-back problem. The airport sign code is not fast graphics code and needs another look, but for the moment it works. As for the other complaints... On Thu, Mar 11, 2010 at 11:13 PM, Heiko Schulz wrote: > Hi, > > > > FWIW, when I'm flying, I see the shading on the scenery > > change > > drastically during the flight as the plane turns and > > pitches. I think > > what's happened is instead of just changing the shading on > > the panel, > > we're changing the shading on the scenery too. FGFS > > didn't used to do > > that, so it's a relatively recent introduction. > I'm not sure what "instead of changing the shading on the panel, we change the shading on the scenery too" means. The scenery and 3d panels are shaded the same way using the global lighting direction. The shading on the panel can change quickly as you turn; obviously the shading on the scenery changes slowly. If you're seeing weird shading changes on the scenery, that could be due to a couple of factors: * Just before the release we found a bug in the shaders that could cause wacky shading changes on ATI hardware. If you're running on ATI make sure you have the latest Effects and Shaders in data. * The shading on transparent windshields might be wrong, or it might be different enough that it causes the scenery's shading to change. * Otherwise, I don't know; it's possible that there is a new bug. I need to see screenshots, a detailed description of FG version, hardware, driver version, etc. > > > > > All the best, > > > > > > David > > > > Now I understand- the whole scenery! (But THIS John never mentioned) > And he had should wrote, that shaders are disabled. > I don't get that from David's posting. > > That's the cause of the bug I guess- when shaders disabled the shading is > changed. That's something really noticeable above the sea or a lake. > And yes, as we offer FGFS for using without shaders as well, it is a bug. > If it didn't look any different with shaders, there wouldn't be much point in supporting them, would there? ;) > > Heiko > > Tim -- Download Intel® Parallel Studio Eval Try the new software tools for yourself. Speed compiling, find bugs proactively, and fine-tune applications for parallel performance. See why Intel Parallel Studio got high marks during beta. http://p.sf.net/sfu/intel-sw-dev___ Flightgear-devel mailing list Flightgear-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/flightgear-devel
Re: [Flightgear-devel] scenery appearance depends on camera tilt angle
On 03/12/2010 06:54 AM, Tim Moore wrote: > I've checked in a fix for the sign-back problem. The airport sign code is > not fast graphics code and needs another look, but for the moment it works. 1) Thanks, the signs are much improved. 2) The problem is not entirely gone. The window for observing the bug is much smaller, but not zero. The symptom is the same: depending on camera tilt angle, the backside of certain signs switches from black to white. http://www.av8n.com/fly/fgfs/img48/taxi-c-at-r-black.png http://www.av8n.com/fly/fgfs/img48/taxi-c-at-r-white.png A cursory survey suggests that *all* the signs alongside taxiway charlie are affected one way or another. Some backsides are almost always black; others are almost always non-black. === Theoretical question: As I understand it, what's going on is: >> The mesh representing the back of a sign is not complete; graphics state >> from other parts of the scenery are leaking into it. Is there some way to check for this at runtime? Is there some calculation that could be done that would detect leakage, or detect meshes that might lead to leakage? Such a check might make debugging easier. Obviously debugging these signs is nontrivial ... and I suspect the signs are not the only items that are vulnerable to bugs of this ilk. -- Download Intel® Parallel Studio Eval Try the new software tools for yourself. Speed compiling, find bugs proactively, and fine-tune applications for parallel performance. See why Intel Parallel Studio got high marks during beta. http://p.sf.net/sfu/intel-sw-dev ___ Flightgear-devel mailing list Flightgear-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/flightgear-devel
Re: [Flightgear-devel] scenery appearance depends on camera tilt angle
On Fri, Mar 12, 2010 at 7:43 PM, John Denker wrote: > On 03/12/2010 06:54 AM, Tim Moore wrote: > > I've checked in a fix for the sign-back problem. The airport sign code is > > not fast graphics code and needs another look, but for the moment it > works. > > 1) Thanks, the signs are much improved. > > 2) The problem is not entirely gone. The window for > observing the bug is much smaller, but not zero. > > The symptom is the same: depending on camera tilt > angle, the backside of certain signs switches from > black to white. > Hmm, the backs of the signs should be gray now. > > http://www.av8n.com/fly/fgfs/img48/taxi-c-at-r-black.png > http://www.av8n.com/fly/fgfs/img48/taxi-c-at-r-white.png > > A cursory survey suggests that *all* the signs alongside > taxiway charlie are affected one way or another. Some > backsides are almost always black; others are almost always > non-black. > > I flew over there in the ufo and saw gray sign backs there... > === > > Theoretical question: As I understand it, what's going on is: > > >> The mesh representing the back of a sign is not complete; graphics state > >> from other parts of the scenery are leaking into it. > > Is there some way to check for this at runtime? Is there > some calculation that could be done that would detect > leakage, or detect meshes that might lead to leakage? > Such a check might make debugging easier. > > Yeah, one could write a visitor that would traverse the scene graph (perhaps fired by a debugging menu command) and report on meshes that don't have a color value or texture coordinates set. > Obviously debugging these signs is nontrivial ... and I > suspect the signs are not the only items that are vulnerable > to bugs of this ilk. > > The things that are vulnerable are mostly geometry that we create "by hand" within flightgear; objects that are loaded from .ac files are usually well behaved (in this respect, anyway). Tim -- Download Intel® Parallel Studio Eval Try the new software tools for yourself. Speed compiling, find bugs proactively, and fine-tune applications for parallel performance. See why Intel Parallel Studio got high marks during beta. http://p.sf.net/sfu/intel-sw-dev___ Flightgear-devel mailing list Flightgear-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/flightgear-devel
Re: [Flightgear-devel] scenery appearance depends on camera tilt angle
On Fri, Mar 12, 2010 at 7:43 PM, John Denker wrote: > 2) The problem is not entirely gone. The window for >> observing the bug is much smaller, but not zero. >> >> The symptom is the same: depending on camera tilt >> angle, the backside of certain signs switches from >> black to white. >> > > I'm speaking off the top of my head here ... does the specular component of scene lighting depend on the view direction? At first thought, I don't think it should, but I think (at least within flightgear) it may. Is this a side effect of opengl's simplified lighting model and the fact that changing view direction implies changing the projection plane? (i.e. fog and aspect ratio of objects can change depending on what part of the project plane they get projected.) Just brain storming here about what might be worth looking into first ... Regards, Curt. -- Curtis Olson: http://baron.flightgear.org/~curt/ -- Download Intel® Parallel Studio Eval Try the new software tools for yourself. Speed compiling, find bugs proactively, and fine-tune applications for parallel performance. See why Intel Parallel Studio got high marks during beta. http://p.sf.net/sfu/intel-sw-dev___ Flightgear-devel mailing list Flightgear-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/flightgear-devel
Re: [Flightgear-devel] scenery appearance depends on camera tilt angle
On 03/12/2010 12:05 PM, Tim Moore wrote: >> I flew over there in the ufo and saw gray sign backs there... FWIW, if I limit the flight to the default screensize and default field of view, I find it difficult to reproduce this bug. On the other hand, if I expand the screen to HDTV size and/or zoom in quite a bit, the bug is easily reproducible. Tangentially related question: Should the screen's x-size and y-size be exposed in the property tree somewhere? I looked in the obvious places and grepped for the obvious names without success. I reckon it would only be a couple of lines of code to add the appropriate listeners. Perhaps somebody who is more familiar than I am with the graphics system could stick this in... -- Download Intel® Parallel Studio Eval Try the new software tools for yourself. Speed compiling, find bugs proactively, and fine-tune applications for parallel performance. See why Intel Parallel Studio got high marks during beta. http://p.sf.net/sfu/intel-sw-dev ___ Flightgear-devel mailing list Flightgear-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/flightgear-devel
Re: [Flightgear-devel] scenery appearance depends on camera tilt angle
On Fri, Mar 12, 2010 at 11:50 PM, John Denker wrote: > On 03/12/2010 12:05 PM, Tim Moore wrote: > > >> I flew over there in the ufo and saw gray sign backs there... > > FWIW, if I limit the flight to the default screensize and > default field of view, I find it difficult to reproduce > this bug. > > On the other hand, if I expand the screen to HDTV size > and/or zoom in quite a bit, the bug is easily reproducible. > Are you seeing gray sign backs at all? There shouldn't be any black or white sign backs in the most recent code. Tim -- Download Intel® Parallel Studio Eval Try the new software tools for yourself. Speed compiling, find bugs proactively, and fine-tune applications for parallel performance. See why Intel Parallel Studio got high marks during beta. http://p.sf.net/sfu/intel-sw-dev___ Flightgear-devel mailing list Flightgear-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/flightgear-devel
Re: [Flightgear-devel] scenery appearance depends on camera tilt angle
On 03/12/2010 04:10 PM, Tim Moore wrote: > There shouldn't be any black or white > sign backs in the most recent code. Please say what commits constitute the appropriately recent code, so I don't need to grovel through the logs ... or at least so that I know what I'm looking for when I grovel through the logs. Is the "most recent code" available on gitorious? Which branch? Or do I need to grovel through the cvs repo too? -- Download Intel® Parallel Studio Eval Try the new software tools for yourself. Speed compiling, find bugs proactively, and fine-tune applications for parallel performance. See why Intel Parallel Studio got high marks during beta. http://p.sf.net/sfu/intel-sw-dev ___ Flightgear-devel mailing list Flightgear-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/flightgear-devel
Re: [Flightgear-devel] scenery appearance depends on camera tilt angle
On Sat, Mar 13, 2010 at 1:04 AM, John Denker wrote: > On 03/12/2010 04:10 PM, Tim Moore wrote: > > > There shouldn't be any black or white > > sign backs in the most recent code. > > Please say what commits constitute the appropriately > recent code, so I don't need to grovel through the > logs ... or at least so that I know what I'm looking > for when I grovel through the logs. > > Is the "most recent code" available on gitorious? > Which branch? Or do I need to grovel through the > cvs repo too? > > Whoops, sorry, it was only in cvs. 262383395d78565 should be in my gitorious simgear repo now, on the next branch. Tim -- > Download Intel® Parallel Studio Eval > Try the new software tools for yourself. Speed compiling, find bugs > proactively, and fine-tune applications for parallel performance. > See why Intel Parallel Studio got high marks during beta. > http://p.sf.net/sfu/intel-sw-dev > ___ > Flightgear-devel mailing list > Flightgear-devel@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/flightgear-devel > -- Download Intel® Parallel Studio Eval Try the new software tools for yourself. Speed compiling, find bugs proactively, and fine-tune applications for parallel performance. See why Intel Parallel Studio got high marks during beta. http://p.sf.net/sfu/intel-sw-dev___ Flightgear-devel mailing list Flightgear-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/flightgear-devel
Re: [Flightgear-devel] scenery appearance depends on camera tilt angle
On 03/12/2010 05:13 PM, Tim Moore wrote: >> 262383395d78565 OK! Sign backs are all nice and gray now. -- Download Intel® Parallel Studio Eval Try the new software tools for yourself. Speed compiling, find bugs proactively, and fine-tune applications for parallel performance. See why Intel Parallel Studio got high marks during beta. http://p.sf.net/sfu/intel-sw-dev ___ Flightgear-devel mailing list Flightgear-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/flightgear-devel
