Outerra forum
Anteworld - Outerra Game => Tech demo, support, updates => Topic started by: gordo on January 28, 2013, 08:51:44 pm
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This is particularly noticeable at dawn and dusk... I'm mostly just curious why there would be sky banding at all (as shown in the screenshot below) when my video card is set to 32-bit color and I assume Outerra uses the full palette available to the system. Is there really no way to deal with this? Can some kind of random dithering be added perhaps, or is that too CPU-intensive for real-time?
--Gordo
(http://i.imgur.com/dMlbboP.jpg)
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I'm not an expert, but it's also a limitation on the number of colors your display has isn't it?
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I'm not an expert, but it's also a limitation on the number of colors your display has isn't it?
That would be true except we all see it and a screenshot captures it. My FW900 shows it so it exists.
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It's a jpeg... That probably doesn't help either, just sayin. And yes, I know we all see it. Does anybody have a display with absolutely unlimited colors? Didn't think so.
There's probably other limitations as well.
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It's a jpeg... That probably doesn't help either, just sayin. And yes, I know we all see it. Does anybody have a display with absolutely unlimited colors? Didn't think so.
There's probably other limitations as well.
The jpeg compression is not introducing the banding. Either trust me, or run Outerra yourself and have a look at a dawn/dusk sky.
Why would you think you'd need unlimited colors to eliminate visible banding? 32-bit color suggests about a 4.3 billion color palette -- well beyond the ability of the human eye to distinguish. Even with an 8-bit alpha channel, there's still 24-bits (or 16.8M colors) and I suspect that we're not even seeing that.
There really shouldn't be banding, that's why I'm asking the question.
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Does anybody have a display with absolutely unlimited colors?
Yes, (http://archive.rebeccablacktech.com/boards/g/img/0247/40/1336541220287.jpg)
The banding in that image is the camera/jpeg compression.
Check this shot out (http://i3.minus.com/ibvrIOr0uLuVND.png) The background of this png is a perfect fade. If your monitor pics this up with banding, it is your monitor.
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... there's still 24-bits (or 16.8M colors) and I suspect that we're not even seeing that.
There's 16.8M colors, but when we are talking about a transition between black and white, there's just 256 levels. And on that screen it's not going from black to white, but from gray to less gray (disregarding the chroma component that doesn't play a role here), which is just a couple of levels in reality.
See it explained for example here: http://19lights.com/wp/2011/09/30/is-8-bits-enough-of-course-not/ (http://19lights.com/wp/2011/09/30/is-8-bits-enough-of-course-not/)
You'd need a card with 30-bit colors to get it better, but then it also depends on internal texture formats used - we'd have to go through the pipeline, checking it.
Dithering can be used too, or maybe a special dithering just for the atmospheric rendering shader ...
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That is a great idea, since the atmosphere is what you notice the most, and I think that is one of the greatest downfalls of many day/night cycle games is when the sun is coming up or going down it stripes all over the place. I would love this addition.
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When there will be clouds and other atmospheric phenomena, the banding is going to be much less visible. Of course there still will be days with clear sky...