I made some addon which has transparency.
http://forum.simutrans.com/index.php?topic=16821.msg160279#msg160279
This is smoke which has transparency.
I introduced in SIGC. The important thing is not only that transparency but also emitting itself in two stage.
Look this movie.
I didn't produce it in SIGC becaus it is difficult to understand by image, not movie.
This motion makes smoke more active.
(http://dl1.getuploader.com/g/JHSDFsimutrans/147/SSsmoke.png)
This is same smoke which has a lot of holes instead of transparency which was made last year.
If your simutrans is before 120.1, try this.
Download link
for112.3~
http://japanese.simutrans.com/index.php?Addon128Japan%2F%B5%A1%B4%D8%BC%D6#SL (http://japanese.simutrans.com/index.php?Addon128Japan%2F%B5%A1%B4%D8%BC%D6#SL)
for120.2~
http://ux.getuploader.com/JHSDFsimutrans/download/144/JHSDF_realsmoke_tr2.zip (http://ux.getuploader.com/JHSDFsimutrans/download/144/JHSDF_realsmoke_tr2.zip)
I'm interested in making addon with transparency, so I made fog as elevated monorail-track.
(https://static.wixstatic.com/media/0a682a_35125f1f90b3417d8a45645e20b31c92~mv2.png/v1/fill/w_600,h_355,al_c,usm_0.66_1.00_0.01/0a682a_35125f1f90b3417d8a45645e20b31c92~mv2.png)
This is fog as accessorie of city, so we can put this as you like, but it is has nothing to do with the game.
http://ux.getuploader.com/JHSDFsimutrans/download/145/JHSDF_fog_track.zip (http://ux.getuploader.com/JHSDFsimutrans/download/145/JHSDF_fog_track.zip)
They are public domain. You can use it freely.
I make new page for 120.2 in my website. You can get newest version of these addon for 120.2.
http://kyuujitujieitai.wixsite.com/simuexpo/makeobj60 (http://kyuujitujieitai.wixsite.com/simuexpo/makeobj60)
If you are interested in them, visit my website. Thank you.
P.S. There is something wrong in picture uploader. If you can't see image, please visit again later.
That's a great addon. Thanks man!