Missing compiz color filter plugin since quantal

[hrjet]

Up until Precise, the compiz-plugins-main contained many plugins:
http://packages.ubuntu.com/oneiric-updates/i386/compiz-plugins-main/filelist

The one I am particularly interested in is the color-filter plugin.

Since Quantal however, the plugin is not present:
http://packages.ubuntu.com/quantal-updates/i386/compiz-plugins-main/filelist

This is an important plugin for the following reasons:
1. Some people have a medical condtion that makes them sensitive to certain colors.
2. For anyone who needs to work at night, or work in a low light condition, it is often useful to filter green and blue light.

[Launchpad Janitor (janitor)]

Status changed to 'Confirmed' because the bug affects multiple users.

[jpka (jopka)]

This plugin is extremely important for save people's eyes. The Color Filter is definetely need to make your environment good look-and-feel. This plugin not only most important part of Compiz for people thinking about eyes health while working on PC many hours a day. This plugin was even one of main reasons for me to switch from Microsoft Windows.
Thank you!

[HRJ (harshad-rj)]

I think the importance of this should be more than a wishlist. It's a regression. And from a health point of view, very important for some users.

Thanks,
HRJ

[Janak Porwal (jp19online)]

Echo HRJ's comments. Please fix this asap!!! Its a regression AND very very important from health point of view. I can say my work has taken a huge toll since installing Ubuntu 13.04. I will need to go back to 12.04 but unfortunately I have wifi issues in that.

[HRJ (harshad-rj)]

The problem seems to be that in compiz 0.9, a lot of code related to OpenGL has changed.

More details here: http://wiki.compiz.org/Development/zero-nine/GLESPorting

THe part releveant to the color filter plugin is:

"ARB Assembly Program Usage

As GL_ARB_fragment_program is not part of the OpenGL core profile or OpenGL|ES, it was removed in favor of GLSL shaders. Unfortunately, that means that any plugin that uses GLFragment to generate GPU assembly shaders needs to have that part rewritten. That warrants another article as it is a much larger subject."

So, someone needs to write a color-filter plugin that doesn't use ARB syntax. It needs to take GLSL shaders as input.

For my part, I will try to write a simple plugin that only filters color channels based on a percentage value. For example: if the percentages are (100, 40, 40), then the resultant color would be (r, g*0.4, b*0.4)

[HRJ (harshad-rj)]

I haven't finished writing my plugin, but meanwhile, I have found an alternative solution using xcalib.

Here is the script that I am using now:
https://gist.github.com/hrj/6561271