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Minos

Cloud light-reflection

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I don't know whether it has been mentionned before, but a neat addition would be light-reflections on clouds. Let me explain: when clouds are above large metropolitan areas, they get a slight orange-reddish color that can be seen from far away.A typical example are Hawaii - West Coast night flights. After almost four hours of complete darkness and even before seeing the West Coast i.e. San Fransisco, pilots can guess the city of SFO simply because clouds are red above it. And I would say that it can be seen from around 150 nm..I would say, that is a great navigation instrument!!CheersCJ

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Good thought... to be honest though, I feel that something like this is not worth modelling simply for the fact that something like that would be very difficult to simulate. It would be tough to make it look real. Personally, I would just be glad to have clouds that are more like true volumetric clouds and not very-well-done 2D images.

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I think you already have 3D volumetric clouds in FS9 if you put your slide bar for 3D clouds to the right...Cheers,Cedric

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Guest gasebah

What I would love is clouds that cast shadows on the ground.Alex

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Guest tdragger

Yes. FS9 has volumetric clouds as long as the Detailed Clouds radio button in the Weather Settings dialog is checked. The % slider is more to control performance.(And, BTW, if you want to debate the fact that our clouds are "volumetric" be prepared for a dissertation from Jason on what that term actually means. )

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>"volumetric" be prepared for a dissertation from Jason on what>that term actually means. )That indeed may be necessary. Some knowledgeable people in this field who actually do clouds/weather stuff for FS9 (e.g. Damian Clark from Active Sky) claim that true volumetric clouds do not exist in FS9, that true volumetric clouds would simply be impossible to do with current hardware from the performance stand point.Michael J.http://www.precisionmanuals.com/images/forum/pmdg_744F.jpghttp://sales.hifisim.com/pub-download/asv6-banner-beta.jpg

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It would add to realisme if clouds would light up from landinglights.[edit] The same when in fog.And one more on the wishlist: Tree shadows (just one extra sprite-plane just above the ground :) )best,Gerrit

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Guest pixelpoke_from_MSFT

>>>"volumetric" be prepared for a dissertation from Jason on>what>>that term actually means. )>>That indeed may be necessary. Some knowledgeable people in>this field who actually do clouds/weather stuff for FS9 (e.g.>Damian Clark from Active Sky) claim that true volumetric>clouds do not exist in FS9, that true volumetric clouds would>simply be impossible to do with current hardware from the>performance stand point.>>>Michael J.>http://www.precisionmanuals.com/images/forum/pmdg_744F.jpg>http://sales.hifisim.com/pub-download/asv6-banner-beta.jpgHi Michael,Speaking as someone who, like Mike "tdragger" Gilbert, is a knowledgeable person who actually did clouds/weather stuff for FS 9... ;)Volume defined:"Volume, also called capacity, is a quantification of how much space an object occupies."source: http://en.wikipedia.org/wiki/Volume"Volumetric Vol`u*met"ric, a. [Volume + -metric.]Of or pertaining to the measurement of volume."source: http://www.dictionary.net/volumetricThe power of the internet means that I don't have to write much else, as I've already blogged about this to some degree here:http://blogs.technet.com/pixelpoke/archive.../08/414035.aspxOf the post, perhaps the most pertinent line is this one:"The only real difference between what FS 9 does with its clouds and what you could create using a higher end particle effects system is the number of particles/sprites used."A single sprite can be representative of a volumetric cloud. This is what TRI's Fly! used to do. We use a lot more,and actually predefine the volume in a 3D tool, but end up using fewer than the billions that exist in a real cloud.If you go to the blog post and click on the movie, the salient visual demonstration of the volume the clouds describe can be found at about the 0.47 second mark.Cheers,Jason

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Guest Dan G Martin

Hi ther Jason I am woundering if some people are confuseing things like "selfshadowing" and radiosity with volume?. Dan Martin

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Guest christian

I think the confusion may arise from the way how you define 'volume'. There are currently 2 techniques commonly used. The most common one is using little 2D billboards distributed over a 3D volume (and hence the description of volumetric is correct) - and this it what FS2004 does. This technique is called the imposter technique and is used in other fractal volumes like trees. One could argue this isn't true 3D, but only 2.5D as it still uses 2D planes.The other technique is using true 3D textures. This requires heavy video memory and I haven't seen many applications that use this technique intensively.While some people may argue that 3D has to be better than 2.5D, this is not necessarily so, imposters can give a pretty good impressions of 3D volumes, and per se, I wouldn't say there is anything wrong with how volumenous the FS2004 clouds look. Rather than quibbling about moving from imposters to 3D textures, I'd rather see proper lighting in FS clouds. I believe this is the area where the cloud algorithms can be pushed much further to look more realistic (ie compare a sunset picture taken in real live vs FS2004 - not really a comparison).Christian

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Guest Peter Sidoli

CJGoing back to your original question of navigating above clouds at night and seeing the location of cities by the glow through the clouds.That is a valid observation which any real night pilot knows about and it is very comforting especially on black nights over inhospitable territory.Just to add to above cloud observations and this also refers to daytime over flat overcasts is the ability to pick out mountain ranges by a step in the overcast outlining the mountain range.Power stations are easy as they cause a localised lump of cumulus to stick out of the overcast and you can often identify your location where there are more than one powerstations by the dotting these cumulus lumps cause.Coastal lines are another! often when flying over sea the first sign of land ahead is the usual cloud line marking that land.The same occurs flying over land on top of cloud and viewing the coastline by a fracturing of the solid overcast along the coastline or the complete breakup of clouds along that line.Flying over fog especially thin fog over the sea has another benefit.That is the location of ships which carve a trail in the fog by the heat generated through their funnels.There are many visual cues for the pilot to note even by the type of clouds and shapes they create.On top of a solid overcast over mountains you have a complete engine failure. look for the cloud rises and the dips which mark the valleys.Let down along the dips and you should break out along a valley line especially if you note the wind direction.Use the same tip for letting down through ice bearing cloud. Take the dips which are thinner and hold less ice than the denser peaks.The clouds are often an interreaction with the land and temperatures which lie below.Peter

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Guest Bell206freak

Quote:+++++++++++++++++++++++++++++++++++++++++++++++++++++++Good thought... to be honest though, I feel that somethinglike this is not worth modelling simply for the fact thatsomething like that would be very difficult to simulate. Itwould be tough to make it look real. Personally, I would justbe glad to have clouds that are more like true volumetricclouds and not very-well-done 2D images. +++++++++++++++++++++++++++++++++++++++++++++++++++++++No offense, but I don't think it'd be all that hard to model, and don't see why the existence of nighttime cloud lighting couldn't be "simulated" in Flight Simulator. Where I live, I'm surrounded by major cities and large towns that always give off enough lighting to "light" the underside of a deck of clouds regardless of height. Here in the Northwest, it's usually considered an essential nighttime VFR flying aid.I would love to see this feature incorporated into Flight Simulator. If not in FSX, then perhaps a future release.

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Guest tdragger

<>Can you explain 3D textures? Do you mean ones that require stereo glasses?

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Thanks Pete.A great explanation. That conforts me in saying that clouds are very subtil VFR navigation aids.Cheers,Cedric

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