What is RTX optimised?

[immortalartscom]

RTX has some limitations at the moment. It does not work with:

1) motion blur
2) anything that automatically generates new geometry
- displacement
- edge rounding shader
- dirt texture node

RTX works best with simple highly instanced scenes, where ray tracing is the dominant factor.

thx for listing this. thats extremly sad. i am working on a big project and for a long time i havent recognized it... and then the big disapointment. scenes now render much longer but at least they look like they should. so for production it is not useable.

vertex displacement IS RTX accelerated.

ok, but its slow. AND, there is also a problem with auto bump and RTX. with that working it would make vertex disp. sooooomehow useable but still much weaker than tex disp in huge scenes. i already addressed that to marcus. he knows. but i suppose/fear this will stay like it is.

texture displacement is one major feature that makes octane unbeatable. and i suppose many users use dirt in every 2nd shader. so for all those cases RTX is not useable.

i upgraded my renderfarm to some 2080ti´s also with RTX acceleration in mind. i hope you understand my little disapointment there... maybe i missed the infos about not working but also "available in interface and not greyed out when using RTX" features. were they listed anywhere? download site, any sub-forumpost?

so rtx is only useable in scenes without dirt, motionblur, tex disp., vertex disp., rounded edges. thats half of the pie.

these are my opinions. i dont want to offend you guys.

[immortalartscom]

ah wait, you mean not accellerated...

i mean its not working right. dirt and autobump have bugs. dirt does not see other objects so it does not work on intersecting objects when RTX is ON. and autobump too. both disappear when RTX is ON. please fix that. if some features arent accelerated its OK but these arent working. marcus knows about that but does not answer anymore.

[Goldorak]

ah wait, you mean not accellerated...

i mean its not working right. dirt and autobump have bugs. dirt does not see other objects so it does not work on intersecting objects when RTX is ON. and autobump too. both disappear when RTX is ON. please fix that. if some features arent accelerated its OK but these arent working. marcus knows about that but does not answer anymore.

yes - I agree. To be clear every scene should work identically with RTX on or off, just some parts primitives and shaders aren’t accelerated (yet) on RT cores yet, so you won’t get as much of a speed up as in scenes where all scene data can be run on RT cores. But even in OctaneBench, with RTX on, we see a 25-30% speed up in worst case scenes (light geometry, dirt shader, no instancing). We do have plans to get dirt, RE and motionblur accelerated in RT cores in future releases.

if you have any scenes you can share (as orbx) showing dirt or other shaders not working with rtx on, we’d love to take a look and make sure we fix by 2020.1.5, which will be the last update before we move to 2020.2.

[linograndiotoy]

ah wait, you mean not accellerated...

i mean its not working right. dirt and autobump have bugs. dirt does not see other objects so it does not work on intersecting objects when RTX is ON. and autobump too. both disappear when RTX is ON. please fix that. if some features arent accelerated its OK but these arent working. marcus knows about that but does not answer anymore.

Hi!
It's true, Dirt needs a fix when RTX is on and you need to use it with multiple interesecting objects, but you can still make it work with RTX on in this case. Just add Dirt to all the involved objects. It will work perfectly with RTX on.

About Autobump, it works with RTX on here in Octane Standalone and Octane for Blender. Do you have a scene we can use to reproduce the issue?

Thanks!

[immortalartscom]

Hi,

so i tried autobump in 2020.1.4 in C4D. Bug is still there. i attached a very simple orbx file. in c4d when i activate RTX (maybe resend the scene too) autobump disapears pass after pass like fadeout. i havent tried in standalone because i am busy.

@ dirt. i have huge scenes. to add dirt in every shader would be the biggest workarround ever
also i use complex dirt setups. that would be nearly impossible.

hopefully you can fix this. at least without speed up. just that scenes look the same as without RTX and only in best case some features benefit from speedup.

thx

[linograndiotoy]

Hi,

so i tried autobump in 2020.1.4 in C4D. Bug is still there. i attached a very simple orbx file. in c4d when i activate RTX (maybe resend the scene too) autobump disapears pass after pass like fadeout. i havent tried in standalone because i am busy.

Looks fine in Standalone with RTX on. I'll try to build a similar scene in Cinema.

@ dirt. i have huge scenes. to add dirt in every shader would be the biggest workarround ever
also i use complex dirt setups. that would be nearly impossible.

Of course the workaround works better as long as the other intersecting meshes are invisible to camera and you only need to see their effect on the "main" mesh. In that case you can apply the same material to all of them (just a simple dirt and a diffuse material would work, no need for any complex setup).

hopefully you can fix this. at least without speed up. just that scenes look the same as without RTX and only in best case some features benefit from speedup.

I agree this needs a fix.

[linograndiotoy]

I've verified in Cinema and we definitely have some problem here. Not happening in Standalone or Octane for Blender, so I guess that's a very specific Cinema issue.

This video shows what happens with Autobump and RTX on:

https://youtu.be/PkfIDjWV2YU

That's the scene:

AutoBump_Issue.zip

(86.47 KiB) Downloaded 170 times

[immortalartscom]

wow, ok, ahmet?

[tcheng00]

Give them time, it'll get fixed. RTX is still relatively new technology. Everyone is facing similar issues.