FEATURE REQUEST: Auto preset switching based on overall scene/screen brightness

I was thinking about this recently... But a lot of times it can be difficult to create a preset that looks good during the day, but ends up looking awful at night. or the opposite...

It would be a great feature where you could assign multiple presets, based on the overall brightness of a scene, as well as set a transition time between presets so it's not instantaneous.

This isn't really possible (in a performant way), since each frame never leaves the GPU, but those sort of decisions are made on the CPU.
You can however simply put your two presets in the same directory and set the previous/next preset keyboard shortcuts in the settings. Switching between day/night preset is only a button press a way then.

Just out of curiosity, could it be done like UIMask shaders?
Imagine two shaders, one is before the other is after. The effects to be enabled/disabled are placed between them. Overall brightness of the frame is calculated. Once a certain amount is reached (either by exceeding or not exceeding), the in-between shaders are by-passed.

I have just been playing Metro Exodus. I'm using Lightroom for making high contrast and some color calibrations. The high contrast option is beautiful for outdoor areas, especially for the desert. But when I enter an indoor area, it is too dark. Maybe this "light calculator mask" disable Lightroom when in indoors.

@canceralp
This should definitely be possible. I think I will try to implement it.

@OP: What you are looking for is luma_fade.fx by Prod80.
This is what i am using to make dynamic presets that automaticcaly change depending on time of day etc.

Go into daylight and make all your color changes there. Save them to a LUT (for performance).
Do the same for Nighttime.
You now have 2 LUT's you can use in a multilut table etc.

Copy the base luma fade shader and change the name (+technique) to game_Day and game_Night.
You should end up with start/end shaders for both in your list.
Now you set the luma range for the day-shader and throw your day-LUT in there.
Invert the values for the nighttime shader and throw your nighttime lut in there.
Done.

You can also throw anything you like in there. On my channel i have uploaded a few test videos with bloow, adaptive darkening/lightning etc.
www.youtube.com/channel/UCfdnxGZvthdSXIRBgcU0f1A

Have a look.

EDIT
Here is also an alternative but for LUT's only.
reshade.me/forum/shader-presentation/289...aptive-color-grading