Some new models utilizing the "sc" suffix or prefix are still work in progress and it is likely that they might change significantly in some next patch. For this reason it is recommended that you avoid using them in your mods at this time.
When basing you model on the original ones, add to your mod also ALL original /automat/ files used by it. The names of the files are generated as SHA1 hash of theirs content so whenever we change the parameters of the material in any way, a different file will be used to store them and the original file might cease to exist if there is no other model utilizing the original parameters.
When modifying original models, always include ALL compoments of the model (pmg+pmd) instead of just those you changed. Otherwise you risk crash if we change the model.
As always when adding new objects to files which support multi-file approach (e.g. road_look.sii) it is HIGHLY RECOMMENDED to use suffix or prefix in the name to avoid conflicts with new objects we are adding in patches. Otherwise you might have to use the batch renaming functionality (see Batch renaming) to fix the conflicts when new patch appears.
Misc useful commands
Running the game with -unlimitedlog command line parameter will disable the standard 1MB limit on size of game log file. This might be useful during update if you want to focus on some bugs first.
Running the game with -validate command line parameter or executing validate command on the console will run special game mode which will load all defined models, prefabs, vehicles and other objects to detect missing textures and similar errors. By examining the game log you can determine what the game was trying to do when error appeared. Note that there is still lot of things which might be wrong which are not checked in this mode.
Running the game with -error_overlay command line parameter will show overlay with number of error and warning messages printed to the log once at least one such message is printed.
How to convert map
Visit large truck dealers and do the following (this steps are basically the same as with the small prefab for 1.15)
Set proper variant of the prefab model to match the brand it sells.
Set the look to the available one (gr_ger_main) if it was set to something else previously.
Select prefab, unselect the main node of the prefab (so only signs remain selected) and press delete to delete the existing signs.
Use "Add prefab signs" to add new signs
Select proper model for the prefab-based "Give way" sign based on country or drop the sign entirely if you already using a custom one.
Remove any unwanted signs.
Do any necessary corrections in the surrounding (e.g. grass, terrain, signs)
Do rebuild (F8)
Changes in chassis definitions
The random selection of chassis model looks now uses explicit list of allowed looks specified in the looks attribute of the chassis accessory data. If the list does not exist, like it might be case with modded trailers or AI vehicles for previous versions, the first look found in the model will be always used (previously a random look was selected from the looks available in the model). If the vehicle chassis uses lods, the fist look might be different between individual lod models leading to appearance changes when game switches between lods. You should update the definition for all modded vehicles which have more than one look in the chassis.
Changes in truck dealer
The large truck dealer prefab did change in similar way to the small prefab in the 1.15 patch. It is now necessary to select the proper variant for the truck branch it represents, regenerate the signs and it might be necessary to do small corrections in its surrounding.