Manipulate gamma ramp for non color server case

[beku]

Support non GPU setups:

• detect color server is not running on the GPU - check _ICC_COLOR_DESKTOP root window atom / oydiColorServerActive()
• dump device link for a particular monitor, including effects, simulation ...
• convert a gray ramp using the device link
• embed the altered gray ramp into a VCGT
  • along the original VCGT, for recovering
  • write a profile
  • icc-examin should contain already some VideoCardGammaTable code
• integrate into oyranos-monitor-white-point
  • call xcalib with the VCGT profile
• publish Invert, Brighten, Darken, ... ICC effect profile

More details and ideas in the original xcalib issue: https://github.com/OpenICC/xcalib/issues/4

[beku]

Conversions will apply to both a global gamma ramp system like traditional 1D LUTs and ICC conversions in some applications. Thus care must be taken to not mix them and result in no double conversions, like double invert or double white point adjustments. Split the effect profiles, which are solely contrast based / curves, like invert, brighten, dim or black n white + reddish and white point adjustment, to become candidates for linear ramp manipulations. All other effects, like grayer, sepia or disability simulations etc., should only be applied only to full ICC conversions.

Add to the effect a meta attribute

• EFFECT_class="...,linear,..."
• EFFECT_linear="yes"

[beku]

The oyranos-monitor-white-point code path and the effect profile sections are covered in #36 and #35 . So this one is almost done and obsolete.