Corona Bitmap and Bitmap Screen problem.

[romullus]

Well, in that case i would say that your scene setup is wrong and result is expected. Enviroment needs proper spherical mapping to work correctly.

It's strange why you don't get see-through effect with native bitmap loader too, because with other renderers it's always like that with screen mapping.

[Frood]

It's strange why you don't get see-through effect with native bitmap loader too

That was also my first thought. But create a reflective sphere in a scene and apply a checker map in screen mode as environment, render with Corona to get a surprise.

So atm I'm more wondering how Tanakov got the result from mockup 1b :)


Good Luck

[romullus]

That's strange indeed. I did quick comparison with mental ray and vray and it looks like Corona get things right with its own bitmap loader (appart from strange distortions), but messes up with max's native texmaps.

[Frood]

The funny thing is, I can neither reproduce your "corona-cbmp-screen.jpg" result nor mockup_1b (Max2016/SP4/Corona 1.6.1) Can you share your scene?


Good Luck


Edit: Wow! And another Max/Adesk black magic weirdness found: when I drag a bitmap node output which is set to env-screen from SME to the "Environment Map" slot of "Environmet and Effects", replacing any other map there, IT CHANGES TO SPHERICAL ENVIRONMENT "automatically" without any notification?! I give up.

[romullus]

Sure, i attached scene, but it's extremelly simple. The difference in behaviour is probably because i'm on 1.7 RC8.

Edit: Wow! And another Max/Adesk black magic weirdness found: when I drag a bitmap node output which is set to env-screen from SME to the "Environment Map" slot of "Environmet and Effects", replacing any other map there, IT CHANGES TO SPHERICAL ENVIRONMENT "automatically" without any notification?! I give up.

Hmm, it's been like that probably since max 2014(2013?), strange that you noticed that only now :] It even somehow recognizes textures plugged through output map, very annoying!

[Frood]

Tnx for the scene, it works like expected. Mine does not. Could you please check the attached scene if bored by moving topics? Renders like the screen of my last post. 2018/2016 RC8/1.6.1, all same result.

strange that you noticed that only now :]

Yes, strange but also very simple: Usually I keep all global stuff in the standard editor (which does not act like this) while doing materials in SME. That may be a reason - but no excuse of course :)



Good Luck

[SHORT CUTS]

Thats sounds like a very old 3dsmax problem i ran into years ago using vray. this happend back in the old days when putting a bitmap in screenmode into the 3dsmax enviroment.
found some old post about it at cgarchitect:
http://forums.cgarchitect.com/39545-environment-map-issue.html
http://forums.cgarchitect.com/18667-problem-rendering-background-bitmap.html

If i remeber it correctly the fix back than was instead of using the 3dsmax enviroment to use the vray enviroment override or the other way around...

[romullus]

Your scene renders like this. Also attached how it looks in mental ray. I feel like my head is about to explode  :/

Yes, strange but also very simple: Usually I keep all global stuff in the standard editor (which does not act like this) while doing materials in SME. That may be a reason - but no excuse of course :)

KABOOM!!!

[Frood]

So I assume you have not found anything "wrong" in the scene, my head joins the explosion right now.

@SHORT CUTS: Only quickly scanned those threads but it looks more like people expecting something wrong from a map set to screen in environment, this is different.


Good Luck

[GeorgeK]

Below are some of my findings on this issue, with environment mapping on "Screen" mode for Coronabitmap vs Bitmap.

Testing was done on a 31 second time limit at 4096x4096 on the latest Corona DB and partially Corona v5,v3. It only includes Screen mapping for environment background. Default blur values were used for both bitmaps, with/without output, both from Environment and Effects Background and from Render Settings > scene > scene environment single map.

Overall Coronabitmap usage for environment reports less noise in all examples (up to 22% difference), an average increase on passes (ranging from 10% to 40% difference), more rays/sec (up to 37% difference).  RAM findings are rather inconsistent.

Issues reported here with problems in reflections, and some more that we were able to reproduce seem to be related to the environment sampler and screen mode. The issue has been reported for further investigation.

As previously mentioned, there is still a 3ds max bug where dragging a bitmap/Coronabitmap node to environment tab (8) it reverts mapping back to spherical from screen. Thankfully it works fine with Corona's Render Settings > Scene Environment or overrides.

(internal id=474052485)

[romullus]

Wasn't this bug resolved long time ago? On the other hand, all this report and subsequent discussion is so messed up, that it's hard to tell what actually was the bug :]

As previously mentioned there is still a 3ds max bug where dragging a bitmap/Coronabitmap node to environment tab (8) it reverts mapping back to spherical from screen. Thankfully it works fine with Corona's Render Settings > Scene Environment or overrides.

Hmm, i don't think it's a bug, but rather a "feature" from Autodesk.

[GeorgeK]

Wasn't this bug resolved long time ago? On the other hand, all this report and subsequent discussion is so messed up, that it's hard to tell what actually was the bug :]

As previously mentioned there is still a 3ds max bug where dragging a bitmap/Coronabitmap node to environment tab (8) it reverts mapping back to spherical from screen. Thankfully it works fine with Corona's Render Settings > Scene Environment or overrides.

Hmm, i don't think it's a bug, but rather a "feature" from Autodesk.

Happy to report that this "feature" still exists in 3ds max 2020.03!