LuxCoreRender Forums

patrickawalz wrote: Tue Apr 17, 2018 3:59 am isn't that what tonemapping already does?

No, tonemapping only adjusts the pixel brightness.
White balance adjusts the colors: https://en.wikipedia.org/wiki/Color_balance

B.Y.O.B. wrote: Mon Apr 16, 2018 9:50 pm I fear we still can't create curves from Python in Blender.

True, but you can look into Corona bridge. Glen made one. I don't know how, but it's working fine. (Had invited him over, hopefully he will visit)
Corona Curve nodes Issue ticket

Sharlybg wrote: Mon Apr 16, 2018 9:45 pm White balance corrector in imagepippeline

Photographer addon should do it. Also packs in quite some other valuable stuff. Am not sure how its WB works with Lux, if at all. I assume it should, since it's blender's color management stuff...



& another Feature Request (already mentioned):
Terminator Artifact Treatment

kintuX wrote: Tue Apr 17, 2018 8:02 am True, but you can look into Corona bridge. Glen made one. I don't know how, but it's working fine.

I know of several workarounds, each has their drawbacks that would be fine if this was some small addon, but a renderer integration should not resort to hacks too often in my opinion (we use same hacks already and I'm not super happy about it).
See for example https://blender.stackexchange.com/quest ... -an-add-on
The basic idea is to find some element in Blender that already has a curve datablock, create it in the background and display the curve UI template where we need it.
But what if the material is linked/appended into another scene? Can the mapping be done in a way that the curve datablocks are linked along?
Also, if the user goes back to Cycles, he might see a "LuxCore_internal_nodegroup" or something similar in his Add -> Group menu all the time (he might even delete it...).
Those are the things we have to consider before we implement a hacky workaround.

In the corona addon you linked (btw. this is the exact code) there is code for handling appending.

In my opinion the better way is to ask the Blender developers to expose the needed features. However that can literally take years (as was the case with Datablock ID Properties).

If you find a better way or want to discuss this further, you can open a github issue so this thread doesn't get off-topic.

My little 2 cents:

Spherical, Cylindrical, Cube and Triplanar mapping, with a button to be computed in local space (no changes when the object moves) and world space.
A button to auto size the mapping to selection, or object.
Edit: Triplanar and others with a blend factor to remove seams.

Bevel edges by shader, with a threshold to ignore edges in a certain angle.

Of course, the denoise (secret thread).

Regards.

Another, not so much feature, but request would be inline documentation of the interfaces used throughout the code - Lights, Materials, Volumes, etc. I feel we might attract a lot more developers if the code and designed choices were explained. For instance, I would love to try my hand at material development in luxcore, but things like passthroughevent don't make much sense to me.

patrickawalz wrote: Tue Apr 17, 2018 8:22 pm Another, not so much feature, but request would be inline documentation of the interfaces used throughout the code - Lights, Materials, Volumes, etc. I feel we might attract a lot more developers if the code and designed choices were explained. For instance, I would love to try my hand at material development in luxcore, but things like passthroughevent don't make much sense to me.

passthroughevent is a random variable (usually they are named u0, u1, etc.). It has a different name because it is the same specific random variable used in multiple places (for instances in Scene::Intersect() calling Material::GetPassThroughTransparency(), Material::Sample(), etc.). It is granted to have the same value across a single BSDF evaluation. A material can use it to take advantage of its particular role, ignore it, etc.

Anyway, we simply don't have time/resourcse/etc. to document internal interfaces. The best way to proceed is to use other materials code as an example, write something, push the code on GitHub and ask an explanation about the obscure parts here.

Sharlybg wrote: Mon Apr 16, 2018 9:45 pm White balance corrector in imagepippeline

You can already adjust the color temperature in light groups (or are we talking of a different kind of white balance ).

Dade wrote: Wed Apr 18, 2018 9:23 am

Sharlybg wrote: Mon Apr 16, 2018 9:45 pm White balance corrector in imagepippeline

You can already adjust the color temperature in light groups (or are we talking of a different kind of white balance ).

No WB is to set a global Temp to the entire image. It is a tonemapping parameter.

Sharlybg wrote: Wed Apr 18, 2018 9:57 am

Dade wrote: Wed Apr 18, 2018 9:23 am

Sharlybg wrote: Mon Apr 16, 2018 9:45 pm White balance corrector in imagepippeline

You can already adjust the color temperature in light groups (or are we talking of a different kind of white balance ).

No WB is to set a global Temp to the entire image. It is a tonemapping parameter.

Uh, and how is this different from setting the temperature of the default light group (in case you have only a single group)

Uh, and how is this different from setting the temperature of the default light group (in case you have only a single group)

it's different . It's not about light color. it's much a post effect. A custom white point selected by user : this thread on corona show the difference :

https://corona-renderer.com/forum/index ... pic=3255.0

Question

not all light is blue or orange tint, tempreture based white balance is not enough

after some discussion an answer from Juraj TalciK :

What's confusing on this ? Proper white balance has Temperature and Tint., or, in CGI, single color compensation slot (like in Vray).
I don't see how this is cluttering. Sure, it's not utmost important at all, but it's not gimmick..

It's not only about lights, color shifts occur upon interaction with materials likewise, so setting your lights to regular temperatures doesn't mean.

Yes you can do it post very easily now but, Corona already has great interactive tone-mapping in frame-buffer, so this would be good addition.