Industrial smog, haze, etc., weather

[mongoose]

Staring a new thread from a post on http://www.sim-outhouse.com/sohforums/showthread.php/133890-City-Textures-rework/page2


Hey Ted, Gecko and I made a "towering smoke column" for Dunkirk which turned out pretty cool. But rather than lots of FPS sapping effects, I wonder if it may be easier to portray burning cities with a 'weather' file? I.e. low level black clouds.

Not to totally take over this thread, I use Pat's smoke and fire columns as facilities in missions, however I have wanted to have industrial smog or haze as weather files, but so far my attempts have been pretty bad. I think Andy M might be better at this, or some of the old ETO guys. We definitely need weather files for local weather effects, both in Germany, but also for England. As I'm on the topic of weather files, some upper level jet stream weather would be nice, as BC missions were often driven off course by those winds. Again my attempts have not been great to say the least.

[gecko]

I have given some though to both of these, but don't have a ready solution to either. Localized weather is certainly possible, but I have no idea how to create a remotely convincing smog layer.

Wind can also be done, and I have even created a way to make it vary by altitude, but the complexity added by making wind a significant factor in navigation is a lot. Not necessarily a bad thing, but perhaps a question of ones simulation philosophy. If you add a new realistic layer of difficulty, but don't also provide the means to mitigate that difficulty that were available at the time, have you made the overall experience more realistic, or less so?

[MajorMagee]

Yes, wind can be programmed to vary based on regions defined by Long./Lat. squares, and altitude. It's a lot of work to accurately map out what you want, but it can be done.

The primary problem with using weather files and cloud textures to create ground fog/haze is that they are 2D, and you end up seeing a line where they intersect the terrain.

[MajorMagee]

From my unpublished Weather Mod


These files are intended to be used with AnKor's 2017 shaders for CFS3 that correct for the gray band at the horizon. I've included an update to every weather.xml file I have. The BackgroundWeather fogcolor in each weather.xml file has been tuned to match the horizon color of the included skybox files. The high resolution skybox files provided are a combination of new textures and modifications of existing ones to smooth out the banding, and eliminate the corner seams as best I could.

The default skyboxes and fog color tend to make the horizon too blue for anything but a zero humidity day. I've tried to mimic as closely as possible the atmospheric effects I see in the real world. The sky generaly goes from blue to bluish grey-white as you approach the horizon because of the water vapor in the air.


The method used for the tuning of the fog color was to check the color at about the middle of the texture using PhotoShop, and then to turn down the brightness by 12% in the color checker. The Hexadecimal RGB values were then put in a calculator with FF added at the beginning, and converted to the decimal equivalent. This is the value that went into the fogcolor. A quick check in the game was then used to refine the brightness value up or done slightly in PhotoShop, and a new hex and decimal value was tried until the match was optimized for most conditions (see table below).


If you are drawing new images each patch is drawn as Front, Left, Back, Right, Front to make the joins seamless.
Front is displayed looking South
Left is displayed looking West
Back is displayed looking North
Right is displayed looking East


In the panoramic_cubic_test.dds file these should be placed in Back, Front, Top, Bottom, Left, Right sequence.
(The default that came with cfs3 was not done correctly.) Some of AnKor's shaders use this file to create cloud reflections on the water, and I think it may be used for the UI background scene as well. You will notice mismatched seams at the edges of the sections if the sequence is not correct.


There is a setting in the weather xml files called skyboxcloudType that can have a few different predefined descriptions:
NoClouds (and ThinClouds) will display the clear_bk, _fr, _up, _dn, _lf, and _rt textures from the effects\skybox folder
FewClouds will display the cirrusonly_bk _fr, _up, _dn, _lf, and _rt textures from the effects\skybox folder
ScatteredClouds will display the scatteredclouds_bk, _fr, _up, _dn, _lf, and _rt textures from the effects\skybox folder
BrokenClouds will display the lowcumulusonhorizon_bk, _fr, _up, _dn, _lf, and _rt textures from the effects\skybox folder
ThickClouds will display the grayhorizon_bk _fr, _up, _dn, _lf, and _rt textures from the effects\skybox folder
If you don't have it explicitly defined in the weather xml file it seems to default to the NoClouds version.


Within the weather xml files there is a parameter called fogcolor that uses a 10 number sequence to define it's color. This is a decimal that converts to hexidecimal as FF followed by the Red, Green and Blue color values as numbers from 00 (darkest) to FF (lightest). A pure gray would have R = G = B. For example scatteredclouds4low.xml has the BackgroundWeather fogcolor as 4288789972 which converts to FF A1 BD D4 which is a light blue grey R=161, G = 189, B = 212. The choice of this shade will have a significant impact on how well the fog will blend into the skybox background colors. AnKors latest shaders address the grey band that frequently was seen along the horizon, but they cannot completely make up for poorly matched fog/skybox colors.


For the skyboxes in this pack the optimal values are:
NoClouds = 4288789972
FewClouds = 4288789716
ScatteredClouds = 4287013048
BrokenClouds = 4290432475
ThickClouds = 4285757562


I've made a few other edits to some of weather xml files to eliminate the flickering line that forms when a cloud texture intersects the surface of the terrain. This was generally done only where it was quite noticable and was accomplished by raising the minimum altitude of individual cloud effect entries.


The cloud texture dds files have also been checked and edited to eliminate any stray non-transparent corners or edges that may have snuck in the aplha layer.

[mongoose]

I have given some though to both of these, but don't have a ready solution to either. Localized weather is certainly possible, but I have no idea how to create a remotely convincing smog layer.

Wind can also be done, and I have even created a way to make it vary by altitude, but the complexity added by making wind a significant factor in navigation is a lot. Not necessarily a bad thing, but perhaps a question of ones simulation philosophy. If you add a new realistic layer of difficulty, but don't also provide the means to mitigate that difficulty that were available at the time, have you made the overall experience more realistic, or less so?

WRT to wind, it did occur to me that if one is using waypoints, warping or not, that would negate the purpose. Back in the past, I did make alternative missions with wps removed and navigation instructions; heading, speed, distance or time, but that was difficult to use in CFS3. To some extent one could cheat by using the map in lieu of the stars or other methods to get a fix, but I never seriously followed up on that.

Smog/haze however would be good.

I also was pondering how to do a Oboe simulation, after Steve's good work on Lorenz and Knickebein, etc.. before my PC crashed. (that's nearly back to where it was).

[sdsbolt]

I also was pondering how to do a Oboe simulation

the latest update I sent can approximate oboe. not perfect though

[mongoose]

the latest update I sent can approximate oboe. not perfect though

Thanks Steve. I haven't got around to that yet but hopefully the coming week. only just moved from using my laptop to the PC.

[NachtPiloten]

What about ship smoke? Not sure how to make that work however.

From effects

bldg_rubble_m_fire_sg

seems that there is a smoke to go with this

Also carrier smoke?

They look like trach effects so slow speed activation?

[mongoose]

We have smoke facilities based on Clive's work for firebomb effects; what we don't have is an effect or weather file to cover, say a whole city like Hamburg, or the Rhur valley. That could be done by a weather file with limited coordinates. It seems so far we lack a good weather dds or whatever. Maybe some fog weather could be changed??

I'll try and dig up some shots of firestorm effects.