Edit 1: More Screenshots
PHAROS: Part 2 - More screens with FPS Overlay : r/flightsim
Hi all!
I've been flight simming since FS98, back when “As Real As It Gets” was on the box. A bit of nostalgia now. After FSX, I drifted away, skipped the P3D era, and never quite got into X-Plane; the aliasing and I just couldn't get along, but props to them for really working on it now.
Then I saw the MSFS 2020 launch trailer. Finally, a proper comeback. A whole, beautifully rendered Earth, the sky, the clouds... pretty much everything I'd spent years imagining while looking out of a virtual cockpit.
I've spent thousands of hours in it since. Yes, most of those were on autopilot at cruise, but the view was half the reason I was there, and hey, it looked pretty good. At some point, another piece of hardware and a new audience entered the picture, and we got some... let's say, restrictions on what we could see. To my eyes, it never really came all the way back after that. That said, we're in a golden age of flight simulation, and I appreciate that the business case for something like this probably wouldn't exist without that audience.
But after staring at the sky and the clouds for however long, I decided to see if I could do something about it.
And I did. It's called PHAROS: Physically-based Haze, Atmosphere, Radiance, Optics and Sky. There's fog in there too, and clouds, but PBHAROFSC doesn't fit on the logo.
It started as an experiment in MSFS 2024. A bit of poking around to see what I could change, which turned into fixing one thing, noticing another, and apparently deciding this was what I was doing with my spare time now.
PHAROS changes how the sim renders atmospheric and volumetric lighting; scattering and extinction through clouds, haze and fog, daytime sky radiance, lunar illumination, and artificial light sources at night. The aim is physically consistent behaviour across those systems, with the real world's oddities, edge cases and not-so-edge cases included. Visibility, light intensity and what you can actually see out of the cockpit should agree with each other.
It is not a preset, a post-processing filter, DLSS/NR/etc, or a weather replacement(😎). It also isn't a performance mod. I've managed to make parts run faster so I could spend that frame-time budget elsewhere, and I still don't have solutions to all of it. Looking at the sky, I'm currently seeing about 5ms of additional frame time over stock in the air, and alot more in some other places.
And before anyone asks for a download: I haven't decided whether this will ever be released or published. It started as an experiment for myself, it's still a work in progress, and I'm still figuring out what I want to do with it. This is me sharing where I've got it to so far, partly to demonstrate what the MSFS 2024 engine is capable of, and partly because I think it's cool.
All the data comes from the sim, except for the haze, fog and upper-atmosphere aerosol data; that data just isn't there. A companion app handles the regional haze and fog calculations outside the sim.
TLDR: I went down a rabbit hole trying to improve the visuals in MSFS 2024 and ended up with PHAROS; an ongoing experiment in physically based atmospheric and volumetric lighting, clouds, fog and night rendering. It's aimed at higher-end hardware. Everything shown is running on my own install, but there's no download or release date. Whether it ever becomes something I release is still TBD.
Fixed / improved
Clouds
- Fine structure at cloud boundaries; edges break into wisps up close instead of smearing into fuzz (WIP).
- Better light attenuation through dense clouds; dark cores instead of uniformly glowing grey.
- Consistent cloud appearance over distance; a cloud 100 km away is the same cloud it will be when you get there.
- Corrected cloud occlusion; no more terrain showing faintly through an optically thick layer.
- Local illumination from the ground beneath each cloud, rather than the ground beneath the aircraft. That last one was a stock bug I found.
Night
- Corrected lunar illumination across moon phases. Stock's full moon is about 7x too bright, and a quarter moon about 40x. A moonlit night finally looks like night.
- Moonlight with its real, slightly warm colour.
- The Milky Way fades as lunar illumination increases; the Milky Way and stars are handled separately.
- City skyglow stays near the ground instead of following the aircraft up to cruise altitude.
- Artificial lights are properly obscured by solid overcast; no street grid shining through the deck.
- Downward-directed street lighting; no more lighting the top of your wing from below.
- A smoother dusk transition, without the sudden “someone hit the switch” drop (WIP).
Airport lights
- Physically based luminous intensities for each fixture type. Stock taxiway lights are 100x to 1,000x brighter than the real ones.
- Discrete intensity steps, like the tower actually sets them.
- Small tolerances in fixture aim and output; real airports aren't made of perfectly identical lamps either.
- Distance-dependent visibility of red obstruction lights, including wind turbines; no more identical red dots at every range.
- Aircraft lights
- Landing-light scattering appropriate to the atmosphere; no solid beam hanging in clear air.
- Backscatter in fog; the light comes back at you the way it does on a foggy road.
Added
- Regional haze and fog. A companion app uses live weather, terrain and air-quality data to calculate conditions outside the sim. Valleys fill with fog while ridgelines stay clear; stock doesn't draw regional haze like this.
- Lights interacting with the fog. Scattering around light sources and extinction over distance; on final, runway lights emerge progressively instead of the whole runway appearing at once. This is where visibility, fixture intensity and RVR become relevant, rather than fog just being a visual effect. In a test with 600 m visibility, I count 18 runway edge lights from the cockpit; the corresponding real-world calculation predicts 20.
- Cloud evolution. Individual clouds grow and decay over time instead of the whole sky changing at once.
- A proper rainbow.
- A weather-dependent daytime sky (WIP). Haze affects the sky's appearance, with more physically consistent low-sun brightness and colour.
What it isn't
- Not a performance mod. A few parts actually run faster than stock, but I spend that straight back on the picture. It's built on a 6800 XT and aimed at high-end cards on purpose.
- Not finished. Everything above runs today, but there's still a queue of things I'm working on.
- Not released. No decision yet. It's invasive and not officially supported.
The one thing I've learned doing this: under the hood, the sim's renderer is much better than its pictures let on. I found a few shortcuts that make everything a bit too uniform, and I didn't like it. Uniformity is the death of realism.
Happy to answer questions...
^(\safe to assume AI was used throughout and many things may not have even been possible without it in any reasonable timeframe.)*