Pack Making JSON Part Slots - DonBruce64/MinecraftTransportSimulator GitHub Wiki

The parts section is simply a list of part slot objects, and what parts can go into those slots. These are also used in parts themselves to allow for sub-parts. Note that all parts with an X pos that is negative will have their part_ismirrored variable set to 1. This is to allow for asymmetrical parts such as wheels with hubcaps and seats with armrests. The every parts section consists of multiple part objects, each of which contain the following parameters:

• pos – An entry of x, y, and z coordinates that define the center point of where this part will attach.
• rot – The x, y, and z rotations that tell MTS how to rotate this part. If no rotations are desired, this can be omitted.
• turnsWithSteer – This parameter is optional. If included and set to true, the part will be used to steer the vehicle. If you want the part to visually turn, you will need to specify this in the animation block.
• isController – This parameter is optional. If included and set to true, the seat at this location will be marked as a controller seat. This allows the player in this seat to control the vehicle. You may have multiple controller seats per vehicle (such as a pilot and co-pilot seat for a plane), but inputs from the controllers are all handled equally, so just because you are in the “first” seat does not mean you get full control.
• isExterior - Tells MTS that this part is located outside the vehicle. Used only for seats, this will result in MTS treating the player like they are standing outside of the vehicle for sound purposes.
• isPermanent – This parameter is optional. If included and set to true, any part in this position will not be able to be removed. Useful in conjunction with a defaultPart that's used for animation and movement of sections of the vehicle that should come with the vehicle, but should never change.
• isSpare – This parameter is optional. If included and set to true, then this part will be marked as a spare. If the part is a ground type, then it will not be used for ground device operations, and if it is a gun it will not be fire-able or select-able. Useful for decorations like spare tires and gun racks.
• isMirrored - This parameter is optional. If included and set to true, this part will be flagged as mirrored. This has no effect except for setting this property on the part, which can then be queried by the part's animations, and making ground devices return a negative rotation for any rotation variables. Mainly used for rotating wheels around on the other side of vehicles, or swapping out seat/door models.
• canDisableGun – This parameter is optional. If included and set to true, then when selecting guns from this seat the ability to select no gun will be present. Useful for seats controlling guns that you may not want to always be active.
• resetPosition – If true, this gun will return to its default yaw and pitch if it not active. This is useful for anyone who likes to keep their large assortment of weapons nice and tidy.
• isCoAxial – This parameter is optional. If included and set to true, and this is on a gun part, and the part in this slot is also a gun, then when the part-slot gun is active, it will be allowed to control the main gun. This allows for switching to SMGs placed on turrets while still moving the turret, but not firing from it.
• forceCameras – This parameter is optional. If included and set to true, then when a custom camera is available for use, then this custom camera will ALWAYS be used in first-person mode. This is designed for seats where first-person mode is not desired, such as tanks or gunner pods. Does not affect third-person mode.
• types – A list of part types that can go in this position. Normally you'll only have one entry in this list, as there's really no reason to have a ground_device at the same location as an engine. There are some exceptions to this, however. One is for interior equipment, like seats and chests, where you want players to be able to choose what they put in that position.
• customTypes – This parameter is optional. If included, this slot will ONLY accept parts whose customType parameter matches one of the items in this list. If the part's customType is not defined, and a blank entry of "" is not present in the list, it will be invalid and cannot be added. Useful for pack creators who don't want their vehicles to play nice with other content packs, or for part slots that really should only accept specific things (like a custom part that's a pickup bed) or slots that should only accept sub-sets of a type of part (such as specific styles of seats).
• validSubNames – A list of subNames this part can go on. If included, this part will only be allowed to go on the specified definition sub-name variants. Used to allow for variant-specific configurations, such as police variants of cars.
• toneIndex – This parameter is optional. If set, then whenever the paint gun is used on the vehicle this part is on, this part will attempt to match the tone specified by the index. If the specified tone does not exist, the part will not change. Default parts will automatically attempt to match tones, but hand-placed parts will not change unless painted.
• maxPartLevels - How many levels deep parts in this slot allow parts to be stacked on it.
• minValue – The minimum value that this slot will accept. Parts with values lower than this will be invalid and show up as red holograms. This differs depending on the part, with engines using fuelConsumption as their value, ground_devices using their diameter, and propellers using their diameter as well. This allows you an easy way to make sure people don't add oversized engines to your little econo-box or put monster tires on the family sedan.
• maxValue – Same as minValue, but the maximum cap this time.
• minYaw – The minimum yaw for this part. Used only on guns. Note that if the minYaw is -180, and maxYaw is 180, then this will bypass all min/max yaw checks and allow the gun to rotate a full 360, even if the gun's JSON specifies bounds besides this.
• maxYaw – Like minYaw, but the max value.
• defaultYaw – The default yaw for the gun in this slot. If the gun has resetPosition to true, then it will move to this position if it's not active. This takes into account the gun's min/max yaw, and if this default exceeds those bounds, it will not be used.
• yawSpeed – How fast, in degrees/tick, the gun can rotate in the yaw direction. Note that if this value, and the value on the part are both specified, the lower of the two values will be used.
• minPitch – Like minYaw, but the pitch value.
• maxPitch – Like minPitch, but the max value.
• defaultPitch – Like defaultYaw, but for pitch.
• pitchSpeed – Like yawSpeed, but for pitch.
• intakeOffset – If this part is an engine, this is how far above the engine the intake is. Used to prevent the engine from drowning while submerged.
  Mainly used in SUVs and military vehicles.
• extraCollisionBoxOffset – If set, this part will create an extra collision box offset in the +Z direction by this amount when placed on a vehicle. This collision box will have all the same properties as this part (wheel, floating, friction, etc.). Useful for treads, where the length depends on the vehicle the tread is placed on. This parameter overrides the same-named parameter in the part JSON, if that parameter is set.
• slotWidth - The width of the holographic part slot box for this slot. Does not apply to generic parts which use their defined size.
• slotHeight - Like slotWidth, but height.
• treadPath - A list of objects on the model that define the path of the tread placed in this part slot. The tread will start on the bottom of the first roller, and will follow the rollers as defined in this path, eventually going back to the first roller.
• treadDroopConstant – If set, this will cause treads hanging along the top rollers to droop. The amount they droop is defined by this constant, with higher values equating to less droop. Note that if you want to use this parameter, it is recommended to keep your idler rollers at about the same spacing from one another, as it is possible to have too much droop on one set and not enough on another. Adjust to suit your vehicle.
• partScale – If included, the part will be scaled along to this X, Y, and Z value. This will be the base scale, and future scaling will multiply this value.
• playerScale – If included, the player will be scaled along to this X, Y, and Z value when sitting in this seat. You can also use this to make the player invisible with a small enough size. This value is multiplied by any scaling applied by the seat. So if a seat scales 0.5, and you put 0.5 here, the scale will be 0.5 x 0.5 = 0.25.
• dismountPos – Like pos, but in this case this is where the player should dismount the vehicle. By default, MTS will attempt to dismount the player directly to the left or right of the seat (depends on X position). If this is set, MTS will instead attempt to dismount the player at this position. Note that in either case if the dismount position is blocked MTS will fall back to allowing Minecraft to dismount the player, which can lead to the player becoming stuck in the vehicle. If you have a vehicle with a complex hitbox, make sure you set this!
• seatEffects – If this part is a seat, this list of potion effects will be applied to the rider while sitting in this seat.
• defaultPart – Normally vehicles come bare-bones, but in the case you want to have the part in this position come with the vehicle, you can set this. If a part name is put here, MTS will automatically add said part when the vehicle is spawned for the first time. Note that MTS won't check if the part actually exists, so either keep things in-house, or require packs you use as a dependency. Note that putting this on an additionalPart without the parent part having a defaultPart WILL crash the game!
• transferVariable - This variable can be used to request parts transfer into and out of this slot. Setting to true without a part will make it try to grab a part from the world, setting it true with a part will make it drop the part into the world, preferably into a part slot on something. Only works with part that can be placed on the ground, and will be set to false after the operation completes.
• conditionalDefaultParts - Like defaultPart, but this is a map of variable values associated with individual parts. If the variable is true, then that default part will be used. If multiple possible parts are present, the first valid one is used.
• allowParentRemoval - If true, this part will allow the parent to be removed even if this part is still installed.
• linkedParts – A list of indexes for parts that are linked to this one. Normally not used, but is required to link wheels to engines, propellers to engines, guns to seats that control them, guns to ammo crates for them to pull from, and effectors to crates they can pull supplies from and feed drops into. The linking is bi-directional: you can link an engine to a wheel, or a wheel to an engine. Also, linking is recursive. So if you link an engine to an axle custom part, any wheels on that part when placed will be linked as if they were in that slot. Similar logic applies for seats to hardmount points that might hold guns.
• applyAfter - If this is set, then the animations on this part slot will first use the animations for this object (not the part) from the rendering section instead of the animations defined here. If the specified object has applyAfter on it itself, then the animations will be gotten recursively until an applyAfter is not found.
• groundDevicePosition - If included, this allows manual definition for which GroundDeviceBox this part is added to (only valid for ground devices). Valid values are front_left, front_right, front_center, rear_left, rear_right, and rear_center.
• animations – This is a list of animations that can be used to move this part based on the animation values. In general, this should only be used in the part needs to physically move, such as wheels being retracted into plane landing gear, or a gun that needs to have an offset mounting track.
• activeAnimations - A listing of conditions for determining if this part is active (default is always active). The exact thing that an 'active' part does depends on the part. Effectors only effect when they are active. Guns can only be used when active. Seats can only be sat in when active. etc. Note that this does NOT block the placement of the part or interaction. That logic is for the interactableConditions.
• interactableVariables - A listing of conditions for determining if this part can be interacted with (default is always interactable). If this is set, then all conditions must be true for the part to be intractable. Additionally, should the part not exist, it will not be able to be placed. Useful for hoods covering engines, doors covering seats, switches activating sub-parts, and trunks covering luggage. If this part is a seat, and the player enters the seat, then all of these variables will be set to false. Similarly, if the player exits this seat, all the variables will be set to true. Useful for auto opening/closing of doors.
• lockingVariables - A double-nested list of variables. If this is set, then this part will be locked in place unless all variables in each of the sets is true (think of variables in a set being an OR condition, and each set being AND ed together).
• constantValues - Identical to the base json constantValues list, when defined here the part's internal constantValues list is appended with whatever is defined here. Useful if certain slots should activate specific internal features! A Quality UNU Addition!