light data shader node color output (GLSL) does not respect energy any more #43250

New Issue

Michael Otto · 2015-01-14T17:47:24+01:00

Michael Otto commented

2015-01-14 17:47:24 +01:00

System Information
Operating system and graphics card

Blender Version
Broken: 2.72
Worked: 2.71

Short description of error
We depend on access to the light energy in many of our shaders, (we used the color output of the light data node for it). This does not work any more.
For GLSL shading, the light data shader node, output "Color" exported the light color before, multiplied by the energy,
Now it only exports the color, regardless of the energy.
In the BI renderer, color is still multiplied with the energy.
The new behaviour in GLSL is more logical imho, but, the energy access is missing. Therefore I can imagine two solutions:

(preferred by me, but not compatible) add an energy output to the node, adapt the BI output to the new GLSL output
restore the old way it worked

What do you think?

Exact steps for others to reproduce the error
select the light in the scene
change the energy
compare GLSL and BI render

**System Information** Operating system and graphics card **Blender Version** Broken: 2.72 Worked: 2.71 **Short description of error** We depend on access to the light energy in many of our shaders, (we used the color output of the light data node for it). This does not work any more. For GLSL shading, the light data shader node, output "Color" exported the light color before, multiplied by the energy, Now it only exports the color, regardless of the energy. In the BI renderer, color is still multiplied with the energy. The new behaviour in GLSL is more logical imho, but, the energy access is missing. Therefore I can imagine two solutions: 1) (preferred by me, but not compatible) add an energy output to the node, adapt the BI output to the new GLSL output 2) restore the old way it worked What do you think? **Exact steps for others to reproduce the error** select the light in the scene change the energy compare GLSL and BI render

Michael Otto commented

2015-01-14 17:47:24 +01:00

Changed status to: 'Open'

Michael Otto commented

2015-01-14 17:47:24 +01:00

Added subscriber: @MichaelOtto

Dalai Felinto commented

2015-01-14 18:26:45 +01:00

Added subscriber: @dfelinto

Dalai Felinto commented

2015-01-14 18:26:45 +01:00

@psyfi I'm yet to got bisect this one, but I suspect it was caused by your changes. Care to look?

Dalai Felinto commented

2015-01-14 18:29:29 +01:00

@MichaelOtto please attach a sample file that can be used to compare the results between the broken and the working versions

Julian Eisel commented

2015-01-14 18:33:47 +01:00

Added subscribers: @Psy-Fi, @JulianEisel

Julian Eisel commented

2015-01-14 18:33:47 +01:00

Just CC'ing Antony correctly

Michael Otto commented

2015-01-15 10:19:36 +01:00

lightnodebug.blend

Sorry, I uploaded one, but must have deleted it again by accident.

[lightnodebug.blend](https://archive.blender.org/developer/F137230/lightnodebug.blend) Sorry, I uploaded one, but must have deleted it again by accident.

Antonis Ryakiotakis commented

2015-01-15 11:29:37 +01:00

I did do some change there related to another bug report. I don't remember if that change was directly influencing that bug but I'll check it again to make sure.

Antonis Ryakiotakis was assigned by Julian Eisel

2015-01-15 20:05:30 +01:00

Sebastian Ullrich commented

2015-01-16 16:34:23 +01:00

Added subscriber: @souljedi