[ErickC]

In an effort to avoid model work that I don't feel like doing, I decided to see what I could do with the sky/clouds as originally intended in OR, that is, a cloud layer with a plain skydome. The default sky dome and cloud textures leave something to be desired to my eye, the sky is somewhat purple and a little on the dark side, while the cloud textures strike me as less like clouds and more like cotton stuffing. Serviceable, but can definitely be improved upon. Obviously, there are plenty of photoreal sky dome textures with clouds painted on them available, but this leaves the problem of fixed clouds that don't vary. The effect is less like a railroad simulator and more like a model railroad simulator. Well, we have Trainz for that, and if we're going to make a model railroad simulator instead of a railroad simulator then we might as well throw away our knuckle couplers and install Rapidos. So a fixed sky - even and especially if it is route-based - is suboptimal.

I elected to experiment a little. I started with one of the FS2004 sky textures, mapped to a sphere in 3DS Max, and rendered into a suitable image, which yielded this:



Note the original texture inset at top left - MSFS uses a texture mapped from the side rather than the top, and it also has a special row of pixels which sets the lighting colour parameters for each sky texture. Note that, in MSFS, the sky is animated in that several different sky textures are used to correct for for time of day, latitude, season, and so on (no, you don't need a separate sky for each route and season if you design your simulation properly, ACES figured this out 20 years ago), hence the need for the texture to somehow indicate how the world should be lit with each sky texture. I also created a stratus layer based on the FS2004 stratus textures:



The end result in-sim looked something like this:



And the clouds looked like this:



The effect was quite satisfactory, but there was a major problem: technically, these aren't redistributable since they are Microsoft property, even though they're not likely to care. But, as a proof-of-concept, it indicated that a satisfactory sky can be made with the sky dome and cloud layers working in conjunction with each other. So, I started digging through all the photos I've taken of the sky and clouds over the years, including several sky photos taken from airplanes. I ended up with this:





Once again, the base texture used to create the dome is inset on the dome image, and not part of the actual texture as exported for use in Open Rails. This texture is a composite of several photos taken at ground level and in the air over the years, usually while taking pictures of locomotives or airliner wings in flight. Overall, I think I had around 7 or 8 sets of sky colour samples from my photos, and the final composite is 8 layers. The majority of the image is an average of several ground-level sky photos, with the upper portion of the sky being a portion of a photo taken from a flight I booked as an excuse to ride a DC-9. This was faded in with a layer mask to create a smooth gradient from the middle of the sky to the top. Several mid-level layers (also blended with layer masks) were added as well, plus a hand-painted layer with colours sampled from the FS2004 sky image because the ground-level photos had too much clutter (trees, buildings, et c.) obscuring the horizon, and the aerial photo was a tad dark there.

The stratus layer is a composite of several of my own photos, heavily edited to loop properly. There is a faint cirrus layer under the stratus layer to mime the effect of multiple cloud layers, although I think OR would benefit from having separate cloud layers. Optimally, it would have a low-level flat stratus layer, a high-level flat cirrus layer, and a middle layer filled with cumulus models generated with sprites at close distances and a wrap-around flat image at far distances, but this is what we have to work with for the present. Here are some shots of the end result.

SUMMER, 0700 HOURS.
1. Clear 2. Haze 3. Light stratus 4. Heavy stratus

[ErickC]

SUMMER, 1000 HOURS.
1. Clear 2. Haze 3. Light stratus 4. Heavy stratus









SUMMER, 1600 HOURS.
1. Clear 2. Haze 3. Light stratus 4. Heavy stratus









SUMMER, 2100 HOURS.
1. Clear 2. Light stratus 3. Clear 4. Heavy stratus









The last image is a wide-angle view of the overall sky.

[ErickC]

As part of this effort, I decided to raid my photos for anything else useful. I also elected to make a new DDS file for diesel smoke. I made 3 opacity levels, but only took screen caps the light opacity because it's probably the most accurate. People have a tendency to make their diesel smoke way too black and way too opaque, and it looks cartoony. I also made a light glow texture based off a night photo I took of an approaching AC4400 many years ago. It's somewhat similar to a recent one uploaded by Nash Gallo, so I am not sure of its real utility, but I enjoy it.













If anyone is interested in the pre-release version of these sky, cloud, smoke, and light glow files, you can get them here: https://www.dropbox....22ei99b867&dl=0

PNG files go in the /content folder wherever your OR executables are located. The diesel smoke DDS goes in the /global/textures folder. I intend to place these files in the public domain once I can be bothered to write docs. If the OR team finds them useful, I also have absolutely no problem with them coming packaged with the executables. I plan on making some test cloud models (both flat and volumetric) at some point to see how simplified cloud models might look in this sky, but that's a project for another day.

[scottb613]

Hi Erick,

Absolutely gorgeous - and don't think I didn't notice all those beautifully strung wires (this should be a priority for ORTS).

Concur - as the 10Kx10K Painted Skydome maker - there has to be a better way. It takes me around (4) days to render a painted Skydome of this scale - and - it completely ties up my computer while rendering - you can't do anything else as it consumes all resources.

I'll take a look tonight when I get in.

Thanks for ALL your efforts.
;)

Regards,
Scott

[singleman74]

Just downloaded and ran with your new diesel smoke and sky dome. I have have to say it looked really good. Keep up the good work. Now if we can just adjust the exhaust from flapping all over the place and have it run like real life. I sure do appreciate all the hard work you do for the sim.

[pschlik]

 ErickC, on 19 February 2024 - 11:23 PM, said:

PNG files go in the /content folder wherever your OR executables are located. The diesel smoke DDS goes in the /global/textures folder. I intend to place these files in the public domain once I can be bothered to write docs. If the OR team finds them useful, I also have absolutely no problem with them coming packaged with the executables. I plan on making some test cloud models (both flat and volumetric) at some point to see how simplified cloud models might look in this sky, but that's a project for another day.

I know some users have expressed displeasure with some of the default textures (the snow"flake" is a white circle...so I can't blame anyone for being frustrated) so there's definitely value in starting a discussion about replacing these. From a technical standpoint, it's pretty trivial to go into the source files and replace the images in order to create a build with different textures, the hard part is getting all the stakeholders to agree it can be done. Someone willing to provide the art is a good step 1 at least.

[QJ-6811]

 ErickC, on 19 February 2024 - 11:23 PM, said:

If anyone is interested in the pre-release version of these sky, cloud, smoke, and light glow files, you can get them here:

the sky dome looks very nice, good work and thanks for your efforts. :sign_thanks:

[ErickC]

 scottb613, on 20 February 2024 - 05:44 AM, said:

Hi Erick,

Absolutely gorgeous - and don't think I didn't notice all those beautifully strung wires (this should be a priority for ORTS).

I can't take credit for anything but the sky, clouds, smoke, and light glow - this is Rory's CN Blackfoot, stock except for the default replacement track shapes by Eric.

[SYogurt]

Looks spectacular! I, too, would be overjoyed to see the defaults in OR replaced with some well thought-out assets. These look great.

[Genma Saotome]

Other than moving them into the correct directory and using keys to increase or decrease effects, I don't know how these effects are controlled automatically in-game. Naturally the OR manual has no mention of weather....

So how is it done?