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Earthview (view source)

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== Development ==
== Development ==
{{FGCquote
|1= There's plenty of ways in which Earthview and FG could be merged into a smoother experience and I'll probably go there again eventually, but I can't really say this justifies urgent action or by itself makes a huge difference. So I'll get to it eventually, but not with high priority.
|2= {{cite web
  | url    = http://forum.flightgear.org/viewtopic.php?p=231896#p231896
  | title  = <nowiki>Re: FG 3.4 RC2</nowiki>
  | author = <nowiki>Thorsten</nowiki>
  | date  = Feb 11th, 2015
  | added  = Feb 11th, 2015
  | script_version = 0.23
  }}
}}


{{FGCquote
Earthview in its current state isn't perfect, for instance in low light it may produce mismatches with the atmosphere shader (as it's fogging model is not precisely the same, and the numerics of the projected Earth sphere doesn't always match what the atmosphere shader computes as horizon). For that reason, its visuals are developed further, but the priority is in general low as by and large the goal to have viable spaceflight visuals is met.
|1= This code may only reach the official repositories if the directional moonlight experiment works, or if these is some interest in using this information (for example for those who are interested in reaching the stars).
The next step is to learn about the fascinating world of the FlightGear renderer:
* https://sourceforge.net/p/flightgear/flightgear/ci/next/tree/src/Viewer/renderer.cxx
* https://sourceforge.net/p/flightgear/flightgear/ci/next/tree/src/Viewer/renderer.hxx
|2= {{cite web
  | url    = http://forum.flightgear.org/viewtopic.php?p=268817#p268817
  | title  = <nowiki>Re: Implementing moonlight (or not)</nowiki>
  | author = <nowiki>bugman</nowiki>
  | date  = Dec 16th, 2015
  | added  = Dec 16th, 2015
  | script_version = 0.23
  }}
}}


{{FGCquote
Over the years, there have been diverse proposals for alternative ways to render orbital visuals in a way that is more integrated with FG - the only viable alternative so far seems to be [[Building FlightGear with osgEarth Integration]], however this lacks atmosphere visuals.
|1= given that there is so much interest in spacefllight recently, it would be cool to work out what else may end up being useful sooner or later if exposed at the property tree level, i.e. to support earthview-like approaches, without having to re-implement/work around rendering logic that already resides elsewhere - even if that just means making things better configurable (or entirely optional using dedicated draw masks), while providing for a seamless transition between the corresponding approaches
|2= {{cite web
  | url    = http://forum.flightgear.org/viewtopic.php?p=269035#p269035
  | title  = <nowiki>Re: Implementing moonlight (or not)</nowiki>
  | author = <nowiki>Hooray</nowiki>
  | date  = Dec 17th, 2015
  | added  = Dec 17th, 2015
  | script_version = 0.23
  }}
}}
 
 
{{FGCquote
|1= You got my 'reaching for the stars' reference :D  The code I'm looking at is a few of the key parts of what needs to be adapted for landing on the moon!  The ephemeris code, the lighting code, and the osg scene set up in the FG renderer.  I was thinking of exactly what needs to be done for a moon landing (or orbit) as I was looking at all of this.
|2= {{cite web
  | url    = http://forum.flightgear.org/viewtopic.php?p=269042#p269042
  | title  = <nowiki>Re: Implementing moonlight (or not)</nowiki>
  | author = <nowiki>bugman</nowiki>
  | date  = Dec 17th, 2015
  | added  = Dec 17th, 2015
  | script_version = 0.23
  }}
}}
 
{{FGCquote
|1= I've been wondering how to reduce the memory footprint of Earthview - which, if you customie it with full resolution Pale Blue Marble which come to eight textures a 21000x21000 pixels each, is an issue even when using compressed dds. Even in the current form with 4096x4096 sheets, loading times are an issue (and I've been toying with allowing simply pre-load everything upon aircraft startup based on a config flag). I've toyed with a select animation showing only the texture sheets currently used (basically, given the local horizon from low orbit, in the worst case you can see 4 texture sheets at the same time, often just a single one). However, upon trying that, it seems the whole model, including de-selected sheets, is loaded anyway. I only found that re-loading improved quite a bit. So things appear to end up in a cache no matter what. So, is there a graceful way to load only the parts of the model / the textures I currently want to show? Or should I just trust the cache to optimize things for me and not worry?
|2= {{cite web
  | url    = http://sourceforge.net/p/flightgear/mailman/message/34579255/
  | title  = <nowiki>[Flightgear-devel] Texture memory management</nowiki>
  | author = <nowiki>Thorsten Renk</nowiki>
  | date  = Oct 29th, 2015
  | added  = Oct 29th, 2015
  | script_version = 0.23
  }}
}}
 
{{FGCquote
|1= I've been making some progress with rendering from orbit http://users.jyu.fi/~trenk/pics/earthview_new12.jpg but I'm still trying to wrap my head around what the sky does. Is there anyone who understands what I am seeing? My Windows binary of ~ a month ago shows the skydome below 310.000 ft or so, then exits it and I see fog-grey. Then comes aone of red sky (which is a rendering artefact caused by the lack of atmosphere definition, the added layer patch is not yet in this binary) but up at 1.000.000 ft, I actually get to see black skies and even sometimes stars come out when the sun is below the horizon(!). My Linux binary of 3 days ago shows fog grey all the way up from 310.000 ft to as far as I tested - no red (as expected since this was fixed), but also no black and no stars. So there is a beautiful starry sky implemented somewhere, and it'd be nice to just use it. Does anyone understand what precisely we render at high altitude and where the starry sky comes from, and can we somehow always render it above 300.000 ft? Alternatively I could give Earthview its own star sphere (to be textured freely...), but then that might hide sun and moon from the view, I don't recall where they are physically located, and having a working moon in the sky is definitely a nice feature. I realize that this is a bit of an exotic use of FG and probably not so many people want to do spaceflight, but if there's a simple way to get a nice night sky at high altitude, I would much appreciate some help.
|2= {{cite web
  | url    = http://sourceforge.net/p/flightgear/mailman/message/32291826/
  | title  = <nowiki>[Flightgear-devel] Nightsky</nowiki>
  | author = <nowiki>Renk Thorsten</nowiki>
  | date  = May 2nd, 2014
  | added  = May 2nd, 2014
  | script_version = 0.23
  }}
}}
 
{{FGCquote
|1= I've been interested in extending Flightgear to low earth orbit and beyond for quite some time (my last crude attempt was at version 1.9...) , and agree with psadro_gm and Zan that a LoD-Terrain engine is one of the crucial steps to this goal.
Vitos, fixing the immediate rendering issues (i think Thorstens shaders might just do that) will not give you more than a foggy sphere. Loading as many tiles as you could see even from LEO in full detail is probably prohibitively memory-expensive, so a LoD system would be necessary. Putting a textured sphere under the geometry would work in first approximation, but i think it would lead to very harsh transitions between it and the detailed normal terrain.
My dream would be extending the terrain engine to work seamlessly from ground to geostationary, and produce beautiful views at every step. I realie that this is a multi-year effort. However, looking at the recent improvement in graphics and consolidation, both with the weather shaders and Rembrandt, i have now hope that it can be achieved eventually. I am particularly happy with Rembrandt, since I feel that several shader issues that would lead to horrible problems at high altitudes have now been decoupled from each other.
I'll try to get up to speed by testing out the Rembrandt branch and Thorstens shader changes, and maybe see if I can rudimentarily make them work together - the faster these two projects get into mainline, the less effort is wasted by duplicating or fixing old shaders. Next, I'd like to help with the terrain engine - trying to reach the south pole in flight gear has left me frustrated recently :/ .
I have quite some professional C++ experience and working knowledge of OpenGL, so I hope I will be able to contribute. On the other hand, I should really finish my thesis, so i might only really get fully into development for some months.
|2= {{cite web
  | url    = http://forum.flightgear.org/viewtopic.php?p=148048#p148048
  | title  = <nowiki>Re: New Flight Gear Terrain Engine</nowiki>
  | author = <nowiki>SiriusGrey</nowiki>
  | date  = Jan 19th, 2012
  | added  = Jan 19th, 2012
  | script_version = 0.23
  }}
}}
Thorsten
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