It's a little weird because the shader was close to the maximum length. I had to shorten some variable names and calculate a couple things in the vertex shader.
There are probably errors in the shader code too since I don't know what I'm doing...
Anyway, there are a couple of new things to set in the CRT-geom.vsh:
saturation tint
They do what they say. I have it set to 150% saturation (too much!) and 0 degrees of tint but you should fiddle with it.
The rest of the options are in the pixel shaders. I think most drivers will be using the CRT-geom_rgb32_dir.fsh so try changing that file first. An easy way to tell if you have the correct file is by disabling "YUV" because the drop in saturation is easy to notice. Here are the new options:
YUV: enables the tint and saturation changes APER: enables the aperture grill effect RGB_M: enables an RGB striped mask instead of Magenta/Green. APER still needs to be set. LUM_VAR_M: enable to fade out the aperture mask for high luminance colors. Keeps whites looking white. LUM_MAG: Sets the strength of the previous effect. 0.0-1.0
Note that if you have an older version of sdlmame/sdlmess that the aperture grill won't show up. I don't know what svn revision (or official release version) the needed glsl change made it into.
I assume you know how to set up the mame.ini to get the shader working. Let me know if it works ok for you.