My (completely biased) opinion: > *2.6.0 > In 2.6.0 we had only the choice between default sky or Zan's sky shader. > In both variants shaders on aircraft and on terrain worked, but there > was the problem with horizon. > > It gave us pretty cool looking skies, as you can see on the 2.6.0 > gallery.
I think the correct way to phrase this is: Under certain conditions (correct view angle, correct weather, correct time of the day) you could make pretty plausible screenshots. Under most real flight conditions, it gave visual artefacts ranging from mildly annoying to outright wrong. > *2.8.0 > Now in 2.8.0 we have the choice between the default sky, or your > Lightfield shader, also named as Atmospheric scattering. > I disregard Rembrandt, as most users won't use it yet for different > reason. Rembrandt has precisely the same issues - not all shaders work with it, so using Rembrandt you will not have some shaders available. I've explained that a (subjective) 1000 times, but let me try again: There is no such thing as 'the skydome having just a problem with the horizon' that can be fixed independently of aircraft effect shaders. If you want to match the horizon, you have to modify the terrain shader because terrain needs to blend into skydome always under all conditions. If you modify the terrain shader, you have to modify the default model shader, otherwise distant models will have different light and fog and stick out. If you modify the default model shader, effect shaders of your aircraft will break unless you take care to modify them as well. > With Lightfield shader also named as Atmospheric Sky Scattering enabled: > we get pretty cool looking skies, a correct horizon but terrain colors > which looks somehow pale Yes. That's realistic physical fogging ~ exp(-x/d) as opposed to non-physical fogging ~exp(-x^2/d^2) as done in the default scheme - complain to nature, I didn't invent the real fog function :-) In the atmospheric light scattering scheme (as in reality) the near zone is a lot more fogged than in default Flightgear for the same visibility range (defined as 'range out to which you can recognize an object). As a result, the overall impression is a lot more pale colors. Plus, currently in Basic Weather there is no way to control the visibility in the ground layer, so you're stuck with the default 16 km - I've asked a few times here if anyone is interested in modifying Basic Weather to support the details of the atmospheric scattering scheme, so far no response. Thus, currently only Advanced Weather makes full use of the features of the scheme. > Limitations are there because some cool shaders like reflection, > lightmap (important for dusk/dawn/night flights) and transition aren't > working. > If we want to show cool images or videos we have to decide if we want a > cool looking sky, or a cool looking everything else. > Both together isn't possible as it was in 2.6.0. That http://imgbin.org/index.php?page=image&id=6391 is how cool it looked in 2.6 to have the skydome rendered in one scheme and the terrain in a different scheme when you don't cherry-pick conditions for the screenshot. That http://www.phy.duke.edu/~trenk/pics/skydome1.jpg is how beautiful the horizon looked when there was no mountain range to hide it. I rest my case. You never had a cool looking sky matching everything else. You carefully had to design the situations in which this wasn't problematic. > The big problem again is, that there isn't a simple developement line > visible anymore. > It is difficult to explain users why some cool features advertised in > 2.6.0 will be "broken" again in the next stable release 2.8.0. > Or with other words: things that wasn't finished yet, had been changed > with new things which aren't finished yet again, but behaves now > different again. To say this again: The only way to 'finish' the skydome shader is to continue what I have started to do, i.e. to change fogging and lighting in every other shader. That is the development line that is happening. Rembrandt adds to the confusion, because making the skydome work with Rembrandt requires to change every shader again to support Rembrandt as well. The manpower to do that is pretty limited - that's FredB, Emilian, Vivian and myself currently working on the shader zoo. So you don't get to combine all cool features at the same time yet, because there are like 30 shaders waiting in line to be processed. But then again, most people start complaining when all the cool features result in ~5 fps, so it's not enough to write the shaders, they also have to be optimized. I manage about one shader per month, which isn't so bad if you think about it. > I'm not sure about. From users point of view we have a skydome shader, > and the lightfield shader which makes use of this skydome shader and > adds some further features but with the side effect of a lot non-working > shaders. I give up. I wish the skydome shader in its inconsistent state had never been included. I've spent a year coding to finally get it consistent without creating artefacts all over the place to read this. You're kidding yourself if you claim the skydome ever worked properly in 2.6. Just create some poor visibility and rain and show us just how nice the skydome shader alone looks with the rest of the scene... then you may appreciate just how big the issues to be fixed really are. I don't think it's a good idea to put cool features which work sometimes if you cherry-pick conditions into a release. Doing so in 2.6 with the skydome shader turned out to be a mistake. Going further into the direction of the mistake makes the problem worse, not better. Cheers, * Thorsten ------------------------------------------------------------------------------ Live Security Virtual Conference Exclusive live event will cover all the ways today's security and threat landscape has changed and how IT managers can respond. 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