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S301
June 1st, 2015, 09:15 AM
I've noticed that the new tbumpenv reflections do not seem to apply evenly across the object. In some areas it appears to be larger, whilst others appear smaller. Some parts also 'mirror' it so that it's upside down.

The following screenshot shows it being different sizes: http://www.zecrail.com/files/tane/TANE%202015-06-02%2000-04-04-11.jpg

The object is split into 4 'segments'. Left is the entire texture mapped to the segment. Mid-left is only the left 2 squares on the segment. Mid-right is the upper two squares, with the map rotated 90deg. Right is the lower two squares with the map rotated counter clockwise.

I have a feeling that mirroring the texture mapping may result in the texture being flipped upside down. I've not yet tested this. EDIT: found an example of the upside down reflections: http://www.zecrail.com/files/tane/TANE%202015-06-02%2000-22-08-17.jpg This is on my 'VR G Carriage Truck' asset that is built-in :)

Regards

WindWalkr
June 1st, 2015, 08:19 PM
tbumpenv certainly isn't new and isn't a true reflection- it's a cubemap. The acid test for correct behaviour with this material is that it matches TS12 behaviour, so that's the first comparison we need to make if we want to know whether the behaviour is faulty. Keep in mind that the exact cubemap image used is different between TS12 and TANE, however the behaviour of the cubemap should match between the products.

The "direction" of the cubemap on the model is defined by the surface normal (which takes into account the per-vertex normals and also the normal map.) You can most certainly flip it upside down deliberately by manipulating the normals (think of a concave mirror), so that by itself is not indicative of a bug.

I should stress here that I'm not saying there isn't a bug, just that the screenshots are inconclusive. I'd welcome you to review this further- comparing the same assets in TS12 would be a great starting point, and double-checking your use of the normal map (and the in-game lighting behaviour resulting from the normal map) would also be a smart move.

chris

S301
June 2nd, 2015, 12:54 AM
Hi Chris
The 'tbumpenv' in TS12 didn't show this issue. On the wheelset, it applied without 'flipping' the texture.

On the test plane, it applies evenly without the change in size (not counting the distortions from the normals map). TS12's was also a lot more intense, the current one requires the 'env' map to be brightened to have an obvious effect (not such a bad thing, as you have more latitude for adjusting it now!).

A screenshot of the example planes in TS12: http://www.zecrail.com/files/tane/S301_20150602_0001.jpg

EDIT, also, when referring to it as 'new' I was referring to the new cubemap. The old TS12 one was the sky dome (or texture, or however it was achieve) of the route, and picked up on the sky colours, sun, and the lightning (during storms). So it definitely seems different in TANE from a creator/user point of view :)

Regards

WindWalkr
June 2nd, 2015, 01:42 AM
The 'tbumpenv' in TS12 didn't show this issue. On the wheelset, it applied without 'flipping' the texture.

On the test plane, it applies evenly without the change in size (not counting the distortions from the normals map). TS12's was also a lot more intense, the current one requires the 'env' map to be brightened to have an obvious effect (not such a bad thing, as you have more latitude for adjusting it now!).

A screenshot of the example planes in TS12: http://www.zecrail.com/files/tane/S301_20150602_0001.jpg

Thanks. I'll chase this one up with you.



EDIT, also, when referring to it as 'new' I was referring to the new cubemap. The old TS12 one was the sky dome (or texture, or however it was achieve) of the route, and picked up on the sky colours, sun, and the lightning (during storms). So it definitely seems different in TANE from a creator/user point of view :)

The TANE cubemap is a hardcoded "compatibility placeholder" for the TS12 effect. TS12 generated a cubemap from the skybox for water reflection purposes, and also exposed this via the tbumpenv material. TANE uses a real reflection render for water reflection, with the net result that there is no skybox cubemap generated and the tbumpenv uses a placeholder instead. There are various ways that this might be improved in the future, but as far as I'm aware nobody's having serious problems with the placeholder cubemap at the current time?

chris

S301
June 2nd, 2015, 01:51 AM
Thanks Chris.

The main issue is that it's applying unevenly, and mirrored (This one is the biggest issue IMO). The only reason I say that is, when looking 'down' at a vertical surface, I seem to see a lot of sky lol. And then when I look 'up' at it, I see a lot of ground. I'm not sure why this is. It also seems that, you often need to look down at a very steep angle to get anything beyond the sky texture. Which is exceedingly bland (it tends to just make things brighter, rather than look reflective).

It certainly does the job, but there's some things I definitely miss about the cubemap that TS12 generated, when used with nicer skies :)

Regards
Zec

Dinorius_Redundicus
November 15th, 2015, 05:00 AM
Was this ever fixed (I mean the dodgy 4-quadrant reflection instead of a realistic reflection)?

The vibe I get from Windwalkr in this thread is that he's not convinced there is anything wrong, but there is a recent thread (http://forums.auran.com/trainz/showthread.php?124154-Strange-texture-effect-in-TANE&highlight=tbumpenv) by creator Jay Holland complaining of the same issue on a reflective water spline of his. It looked OK in TS12 but has this problem in TANE.

I'm thinking there's still a problem.


.

WindWalkr
November 15th, 2015, 09:44 PM
No, this hasn't been fixed. It's still an open issue; we won't know whether it's a legit bug or just mistaken expectations until somebody's had time to look into it in more detail.

chris