(Daily Build 2020-02-27 & v5) - Up to 50% Ray Reduction when using bump maps

[Nejc Kilar]

Hello yet again! :)

So another really big issue with the bump maps that kind of make Corona not production ready at all :\

Turns out that if you are using bump maps without nesting them in the Corona Bitmap first you get about a 50% speed penalty. As soon as you nest it in a CBitmap then the rays jump back up again.

I'm attaching a quick video illustrating an issue. Do note that the scene is really simple - Imagine getting a speed penalty like this on a scene that needs 4 hours to render :\

Anyway, using the CBitmap by itself isn't a problem but CBitmap doesn't work with the Layer shader and because the Projector shader is broken too (see my other bug reports) you basically _can't_ scale bump maps in Corona for Cinema 4D. I hate to be negative here but thats like... A super basic thing to do.

Tough stuff :(

OS: Windows 10

[burnin]

Efficiency sake, kindly post just a simple exemplary test file w/ steps to reproduce...

[Nejc Kilar]

Open a scene -> create a sphere -> create a material -> put a bump in the material -> issue reproduced.

Not sure we need a scene for this one :)

[Evolist_ua]

Hi, corona render for c4d have this problems with dual cpu (2cpu on motherboard, not 2 core).
Exactly a year ago, I wrote about this problem here https://forum.corona-renderer.com/index.php?topic=24238.msg154510#msg154510
And month ago there https://forum.corona-renderer.com/index.php?topic=27391.msg164203#msg164203

[Nejc Kilar]

Hi, corona render for c4d have this problems with dual cpu (2cpu on motherboard, not 2 core).
Exactly a year ago, I wrote about this problem here https://forum.corona-renderer.com/index.php?topic=24238.msg154510#msg154510
And month ago there https://forum.corona-renderer.com/index.php?topic=27391.msg164203#msg164203

Oh right, totally forgot about your thread! Yes Sir, I have a dual socket 2696v3 system and after going through your thread again I feel like we have the exact same issue.

And while the CBitmap solves the halving of the rays you do lose the ability to scale / transform bump maps with it which in my opinion renders it useless for this purpose.

Thanks for chiming in!

[Evolist_ua]

Yes(( I’ve been waiting for developers to fix this for more than a year.

[Beanzvision]

(Internal ID=487244916)

[burnin]

AMD TR seems unaffected.