Documentation/Engine/Random Road Events

Random event preview

Road events (RE) are dynamically generated situations on roads present in ETS2 and ATS.

RE are defined from several cutscenes placed along the road. RE distinguishes 3 types of cutscenes:

• Start cutscene - The first cutscene of the RE, only one per the RE.
• End cutscene - The last cutscene of the RE, only one per the RE.
• Layer cutscenes - Cutscenes between Start and End cutscenes.

According to the length of the RE and the lengths of cutscenes, the space between start and end cutscenes is filled with layer cutscenes.

Composition of RE:

Defining random events

All RE are stored in "/def/world/journey_road_event.sii" as list of journey_events_road_event units.

Example journey_road_event.sii file definition:

SiiNunit
{
# For modders: Please do not modify this file if you want to add a new entry. Create in
# this directory a new file "<base_name>.<idofyourmod>.sii" where <base_name> is name of
# base file without the extension (e.g. "city" for "/def/city.sii") and <idofyourmod> is
# some string which is unlikely to conflict with other mod.
#
# Warning: Even if the units are specified in more than one source file, they share the
# same namespace so suffixes or prefixes should be used to avoid conflicts.

journey_events_road_event : j_re.acc_uni_p
{
    signs_distances_outer[]: 50

    layer_min_curve[]: 0.0
    layer_max_curve[]: 15.0
    
    max_length: 55.0
    min_length: 55.0
}
journey_events_road_event : j_re.acc_plane
{
    start_cutscene: j_cut.acc_stop_li
    layer_cutscenes[]: j_cut.acc_mid
    end_cutscene: j_cut.acc_plane

    min_shoulder_space: 3.0
    outer_lane_allowed: true
    centerline_displacement: true
	
    layer_max_curve[]: 2.0
	
    weight: 10.0

    parent: j_re.acc_spec_p

    name: "Accident country specific plane (1)"
}
}

Defining cutscenes for random events

All cutscene attributes of RE: start_cutscene, end_cutscene, layer_cutscenes, mirror_cutscenes, signs_cutscenes_inner and signs_cutscenes_outer are using same unit type: journey_events_cutscene, which are listed/defined in "/def/world/journey_cutscene.sii".

These cutscenes are then linked to RE via their unit names. For example cutscene "j_cut.acc_stop_li" defined below is featured as start cutscene of RE "j_re.acc_plane" in example above.

Example journey_cutscene.sii file definition:

SiiNunit
{
# For modders: Please do not modify this file if you want to add a new entry. Create in
# this directory a new file "<base_name>.<idofyourmod>.sii" where <base_name> is name of
# base file without the extension (e.g. "city" for "/def/city.sii") and <idofyourmod> is
# some string which is unlikely to conflict with other mod.
#
# Warning: Even if the units are specified in more than one source file, they share the
# same namespace so suffixes or prefixes should be used to avoid conflicts.

journey_events_cutscene : j_cut.acc_stop_li 
{
    cutscene_tokens[]:     acc_stop_li1
    cutscene_tokens[]:     acc_stop_li2

    left_width:             80.0       // [m]
    right_width:            5.0        // [m]
    sequence_mode:          pseudo
}
journey_events_cutscene : j_cut.acc_mid
{
    cutscene_tokens[]:     acc_mid_1
    cutscene_tokens[]:     acc_mid_2
    cutscene_tokens[]:     acc_mid_3

    left_width:             15.0       // [m]
    right_width:            15.0       // [m]
    sequence_mode:          pseudo
}
journey_events_cutscene : j_cut.acc_plane
{
    cutscene_tokens[]:     acc_rare_1
    
    left_width:             35.0       // [m]
    right_width:            25.0       // [m]
    sequence_mode:          pseudo
}
}

Cutscene width

In case of RE, cutscene definition of type journey_events_cutscene also uses left_width and right_width attributes, which defines the length of the cutscene. This two attributes are very important as they determinate how much space is between different cutscenes, how many layer cutscenes can be places in whole RE and where traffic blocks will be placed.

To determinate left and right width one has to:

1. Add cutscene on on the part of the road.
2. Rotate the cutscene in map editor so that driving direction is from right to left:
   
   
3. Once seeing cutscene as on picture, use the ruler tool in map editor to measure distance from cutscene origin point on each side.
4. Use measured widths in cutscene definition.