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andi06
June 10th, 2015, 03:25 AM
Blue sky department :-)

In TRS reflections seem to be based only on the relative position and orientation of the observer and the object. This means that following a train in chase view the reflection component of textures will be more or less static.

In the real world the movement of the train past other objects causes a rapid change in reflections and I would think that if this could be emulated in some way the results could be very impressive.

I know that for practical purposes you can't actually calculate 'proper' reflections of adjacent objects, but would it be possible to develop a material where the environment map changes in proportion to the speed of the train. Conceptually, if the env-map were to be thought of as a sphere or a drum then you would spin the map to produce changes in the reflection on the traincars.

VinnyBarb
June 10th, 2015, 04:34 AM
Very good idea, I think this could be made possible. The following has nothing to do with what you are proposing but as example, Skyrim has a way to highlight normal mapping wherever there are shadows placed in game (buildings, people, animals, ground, trees etc.) where a sort of "invisible" sun with its subdued shining effect only and no shadows is very slowly moves horizontally from one side to the other and then slowly back again and repeating this on and on very slowly, thus highlighting the 3D effect on edges first, slowly moving across stones and blocks and other very prominent 3D protrusions, which are in shade, say, like on a vertical castle wall, houses and people. Probably hard to describe but very easy to see in games like Skyrim and probably some others.

What I mean, the real sun is still up in the sky wherever it is at a given moment and moving sunup to sundown as in Trainz, the other sun, as said above is another sort of a much lesser, subdued "invisible sun" effect not throwing any extra shadows, for a better way of describing this. As a very excellent visual experience on the areas on objects where the real sun is not shining on such shadows on walls or any such other shaded areas on objects. As we presently do not see ANY normal map 3D effect on shadow areas in TANE, this could also make it into TANE if programmers are smart and are willing to do this.

Programmers might/should sometimes study how other games implement any such better visual experiences, they might be pleasantly surprised what other games can offer. One of these games might even have already implemented something like andi06 is wanting to bring into TANE.

VinnyBarb

TRam__
June 10th, 2015, 05:17 AM
As we presently do not see ANY normal map 3D effect on shadowThat's called parallax occlusion mapping. http://en.wikipedia.org/wiki/Parallax_occlusion_mapping (http://en.wikipedia.org/wiki/Parallax_mapping)

But it can't work without height map, that isn't supported with current ts12-like materials and ts12 exporters. Normal map isn't sufficient for this method to work.



in proportion to the speed of the trainthe object's [relative?] speed currently isn't sent to GPU :) . And it isn't clear, what part of the environment map should be "rotated".

WindWalkr
June 10th, 2015, 06:06 AM
I know that for practical purposes you can't actually calculate 'proper' reflections of adjacent objects

Possibly, to some extent. You can't (without ray-tracing type tech) have true reflections everywhere, but you could have a system which picked the few most relevant reflective planes and then fall back to cube-maps for anything else. It would be expensive, and time-consuming to build, but the end result might be nice :)



but would it be possible to develop a material where the environment map changes in proportion to the speed of the train.

Yeah, there are a variety of ways to make the reflections look more lifelike. Definitely something to think about in the longer term.

chris

TRam__
June 11th, 2015, 09:36 AM
You can't (without ray-tracing type tech) have true reflections everywhereTrue reflections required only for the side view mirrors of locomotive cabin. Sometimes that mirrors are placed on the platform, and on the modern trains and metros they are replaced with surveillance cameras and displays in cabin/on the platform.