Eye adaptation is not working

[Kubuxu]

It causes HDR not to adapt and look bad overall.

@marcin212

[Cervator]

Thanks for the report and earlier discussion on IRC. I'll park this in @emanuele3d's queue hoping he'll get a chance to look at it sometime, or maybe somebody else with some rendering expertise will figure it out :-)

[Kubuxu]

I am not sure if it is eye-adaption or not. Either way, without eye-adaption it shouldn't be that dark IMHO.

It just looks like ambient light is non-existent.

[Cervator]

Tested out after #2247 and it is hard to say what is changed. It seems the overall world is now a little darker with eye adaption off but there seems to be no effect/change if you go under or out from tree coverage.

Also reminding myself here that eye adaption is the thing where crossing from a very bright area to a very dark area (or vice versa) leaves you mildly blind for just a few moments.

[4Denthusiast]

As it currently works, there seems to be no delay for eye adaptation. I think this is fine, as I've found that a bit jarring in other games as the screen brightness is gradually changing but I'm not getting feedback from my eyes at the same time that they're making the adjustment.

I do think that the eye adaptation effect is currently far too small, however. From my own experience of real life, a large difference in scene brightness is often barely noticable. If we do want to have simulated eye-adaptation in game, it's probably best to mostly avoid representing in-game darkness with actual screen darkness, as that means that people are affected differently depending on their real-life scenario (e.g. gamma settings, other bright areas on the screen, bright reflections from the screen). It would seem reasonable to me (with the caveat that I've not actually tried it, and don't have any experience in this area beyond having experience using human eyes) to have the displayed brightness be about half as much from full daylight to just before switching to rods (at which point, fade to greyscale as well as continuing to get darker and blurrier).

The main problem with realistic HDR in Terasology is probably that we don't have a realistic lighting model to start with. In order for visibility in low light levels to be useful, there need to be areas which are sensibly dimly lit, but the block-based lighting approximation is least accurate near (and beyond) the edges of the lit area. To some extent I don't think there is a reasonable solution to this, as if it's possible to see in dim light, it should be possible to light an entire large room a visible amount using a single light-source (with a suitable light-shade).