[REQ] MeshLight Excitance Multiplier <-- Blender Exporter

[Apollux3D]

As the developers surely already know, there is this conflict where for certain variables Indigo takes as input a number from 0 to infinitum, while in Blender the sliders always have a set maximum and minimum.

IMO, where that Blender limitation becomes more obvious is on the "Emit" value for mesh objects when you are using the SunSky model.

On the current incarnation of the Exporter, the maximum value the user can get on the "Emit"/"Exitant Radiance" is somewhere around 26, wich is fine for the Background lighting model, but totally unadecuate for the SunSky model.

From my experimentation on Indigo with MeshLighs + SunSky+ Reinhard tone mapping, you beggin to get usable results near 1,000,000 on the exitant radiance.

So, what I´m asking is a gloval multiplier setting for all meshlights objects that would default to 1,000,000 when using Reinhard + SunSky. For the default value on other overiment combinations I hadn´t researched further enough, but I´m sure the developers are more in the knowledge than I.

The multiplier value could be a sub-set of the SunSky model only, but I guess that having the multiplier always at hand is a quick and easy way to
re-balance the lighting of the scene without editting every single material.

[zuegs]

Hi Apollux3D
Yes, we had some past discussions on that issue...
http://www.indigorenderer.com/joomla/fo ... .php?t=768
...about a hard-coded multiplier for blackbody and peak emitters (perhaps also RGB emitters).

The editable multiplier on exporter GUI is a good idea to adapt individual preferences and the possibility to set it to "1" to be backward-compatible for older scenes.

I think this would be something for next release

[Apollux3D]

The editable multiplier on exporter GUI is a good idea to adapt individual preferences and the possibility to set it to "1" to be backward-compatible for older scenes.

I think this would be something for next release

Precisely what I was thinking... but your answer brings even more questions..

1.- Do the exporter releases and the Indigo releases are coupled? I mean, can they be in-between releases of the exporter?

2.- I was initially imaging the multiplier as a set of GUI sliders on the exporter, say one for each type of light source. The Sky gain slider already is a sort of multiplier for the sun light source.... each slider would be able to travel from 0.001 to lets' say 10,000,000 ? Can Blender sliders deal with such big margins?

3.- Regarding question #1, from my non-coder point of view it doesn' t seem like such a radical task to be postponed untill the next mayor update (assuming the suggestion for the multiplier gets accepted, don't want to impose anything to you guys). The current "Emit" mapping doesn't need to be updated, the multiplier would just take the output from the mapping and do a simple mathematical multiplication before the XML file is written.

4.- Now, finding the best "default" setting for each possible escenario, that is some serious intellectual task. But for starting the default could be left in "1" and allow the community to test it and report back with setting works best for each case... just my mind wondering in overdrive mode

[zsouthboy]

A simple box on the exporter page in blender that said "Multiply the number I set for emitters by :" would be easy to add yourself, if you want that functionality.

BTW the exporter is a community project, so you can (if you want to) learn some Python and start helping.