Control Reshade from game mod

I've been toying for a while with the idea of using some sort of signal sent from a modded game in order to modify Reshade behavior.
My main example of use would be in games like Dark Souls, Blade of Darkness, Lords of the Fallen, etc where you can lock-on into enemies during fights. When you lock-on you are actually "focusing" completely on a particular position in space. Also the camera tracks automatically that enemy. So what I would like to do is to tell reshade that when I activate a Lock-on I also want to exaggerate the DOF effect to isolate better the character in focus. I also would need to tell reshade the enemy distance to camera so it can do a follow focus.
All those dynamic behaviors would look amazing and add life to any game.

Now. How can this be done? Any Ideas?

I guess one way to do it would be to create a custom HUD element on the game that draws a pixel in a corner of the screen. The game would change the value of each RGB chanel of that pixel depending of the situation: lock-on activated mapped to R channel, distance to camera mapped to G channel and so on.
Then reshade would sample that pixel giving you three different control chanels (RGB) that would be mapped to the corresponding effects.
Is this a way to do it? Is there a better way to for a program to communicate with Reshade?
Thanks.

piltrafus wrote: I guess one way to do it would be to create a custom HUD element on the game that draws a pixel in a corner of the screen. The game would change the value of each RGB chanel of that pixel depending of the situation: lock-on activated mapped to R channel, distance to camera mapped to G channel and so on. Then reshade would sample that pixel giving you three different control chanels (RGB) that would be mapped to the corresponding effects.
Is this a way to do it?

This is indeed a good idea and should work. There isn't a direct way to communicate with ReShade currently, but it's something I'll keep in mind for the future.