Maybe this will help. This is in the new_config_vars.txt file.
Code:
d3d_disp_sw_cc
only has any effect in combination with "use_d3d_display", enables software gamma and color processing. The
benefit of doing gamma in (shader) software rather than HW gamma, is that there is less quality loss
because it can be applied on the higher precision floating point or 10-bit render data, before getting
down converted to a displayable format. Whereas HW gamma is applied on the already downconverted displayable
format. Another benefit is that gamma works in windowed mode, where HW gamma doesn't work.
Enabling color processing comes with some performance loss.
It's possible to override the CC shaders with custom ones. Either to customize the gamma or color processing,
or to add additional processing like noise/dithering. When there's additional processing in the shaders, that
should be done regardless of gamma/color processing being active or not, then define "d3d_disp_sw_cc 2". It
will make sure the CC shaders are always used.
For further details and example shaders see the "doc/sw_cc" directory.
d3d_disp_sw_cc_bright <val>
brightness level when "d3d_disp_sw_cc" is enabled, default is 0. A value of 1 would make everything white.
This option is only provided for completeness, it's more appropriate to adjust gamma.
Does not affect menu screens.
d3d_disp_sw_cc_contr <0.0 - >
contrast level when "d3d_disp_sw_cc" is enabled, default is 1. This option is only provided for completeness,
it's more appropriate to adjust gamma.
Does not affect menu screens.
d3d_disp_sw_cc_sat <0.0 - >
saturation level when "d3d_disp_sw_cc" is enabled, default is 1. A value of 0 is completely desaturated (b&w).
Does not affect menu screens.
d3d_disp_sw_cc_rgbfilter <0.0 - 1.0> <0.0 - 1.0> <0.0 - 1.0>
RGB color filter when "d3d_disp_sw_cc" is enabled, default is 1 1 1 (white). For example to get a old photo
type of look (sepia) you could do "d3d_disp_sw_cc_sat 0.25" and "d3d_disp_sw_cc_rgbfilter 1 0.7 0.3".
Does not affect menu screens.
d3d_disp_sw_cc_hwgamma
only has any effect in combination with "d3d_disp_sw_cc", forces gamma to be applied by display HW like it
does when "d3d_disp_sw_cc" is disabled, but other color control like saturation and color filter are still
applied. This _might_ help reduce any performance hit (induced by "d3d_disp_sw_cc") slightly, at the expense
of gamma not working in windowed mode and potential minor quality loss. Another potential issue is that
contrast/brightness calculations are normally applied after gamma, with this option enabled gamma is applied
after brightness/contrast (if brightness/contrast isn't used, i.e. set to default, this is of no concern).