JCM:Scripting:Documentation:Utilities

Utilities

As the scripting functionality is based on the Nemo Transit Expansion, a number of helper classes are implemented from NTE to provide some information or to implement functions more simply.

Output of debug information

static print(params: Object...): void

This function outputs a message to the Minecraft log (the message is not displayed in the game). Any number of arguments of any type can be passed to the function.

Versions

Functions are provided where you can get the version number to ensure compatibility with different versions of mods (if any).

Functions	Description
static Resources.getAddonVersion(modId: string): string	Obtain a version of a mod registered to the scripting functionality. By default, the possible modId are: mtr jcm
static Resources.getMTRVersion(): string	Returns the version of the MTR, for example, 4.0.0-beta-11+1.20.4. DEPRECATED: Use Resources.getAddonVersion("mtr")
static Resources.getNTEVersion(): string	Returns the version of the NTE. As there are no NTE version for MTR 4, this function is hard-coded to 0.5.2+1.20.4.
static Resources.getNTEVersionInt(): int	Returns the NTE version as a number for easy comparison. As there are no NTE version for MTR 4, this function is hard-coded to 502. (For 0.5.2)
static Resources.getNTEProtoVersion(): int	Returns the NTE protocol version. As there are no NTE version for MTR 4, this function is hard-coded to 2.

TextUtil

MTR uses the station naming format Name in CJK|Name in another language||EXTRA, so TextUtil is implemented to provide functions to separate these parts.

[Translator's note: MTR distinguishes text in CJK languages from the rest to allow them to be displayed nicely. It is not necessary to use CJK languages, e.g. you can easily use the scheme Name in Russian|Name in English||EXTRA or even use more languages.

For reference, CJK is Chinese, Japanese and Korean].

Functions	Description
static TextUtil.getCjkParts(src: String): String	Returns the CJK parts of the passed string.
static TextUtil.getNonCjkParts(src: String): String	Returns the non-CJK parts of the passed string.
static TextUtil.getExtraParts(src: String): String	Returns the extra part of the passed string.
static TextUtil.getNonExtraParts(src: String): String	Returns everything except the extra part.
static TextUtil.getNonCjkAndExtraParts(src: String): String	Returns everything except the CJK parts.
static TextUtil.isCjk(src: String): String	Checks if the string contains CJK characters. [Translator's note: this function is supposed to return a Boolean value].

Timing

Functions	Description
static Timing.elapsed(): double	Returns the running time of the game in seconds. It is constantly increasing. It does not increase during pause.
static Timing.delta(): double	The time difference between the current render call and the previous one. This can be used, for example, to calculate the angle by which the wheel have turned during the elapsed time.

StateTracker

Sometimes it is necessary to take transition states into account. For example, to play an animation only once when a certain condition is reached (because if (…distance < 300) ctx.play… would be satisfied every frame after the condition was met, and then play every frame after that, which would result in hundreds of animations), or to play an animation in the first second after a page switch.

Since each object should have its own tracker, you would probably want to store it in the script's state variable.

Functions	Description
new StateTracker()	Creates StateTracker.
StateTracker.setState(value: string): void	Sets the new state.
StateTracker.stateNow(): string	Returns the current state.
StateTracker.stateLast(): string?	Returns the previous state. If it does not exist, null is returned.
StateTracker.stateNowDuration(): double	Returns the amount of time the current state lasts.
StateTracker.stateNowFirst(): boolean	Was the state just changed by the setState function in this loop or not?

CycleTracker

This is a StateTracker that automatically switches on a cyclic basis by time.

Since each object should have its own tracker, you would probably want to store it in the script's state variable.

Functions	Description
new CycleTracker(params: Object[])	Creates a CycleTracker. The parameters are the states it will switch through and the duration of each state in seconds. Example: new CycleTracker([“route”, 5, “nextStation”, 5]).
CycleTracker.tick(): void	Updates the status based on the current time.
CycleTracker.stateNow(): string	Returns the current state.
CycleTracker.stateLast(): string?	Returns the previous state. If it does not exist, null is returned.
CycleTracker.stateNowDuration(): double	Returns the amount of time the current state lasts.
CycleTracker.stateNowFirst(): boolean	Was the state just changed by the setState function in this loop or not?

RateLimit

Some tasks do not require too frequent execution, for example, the display may not be updated every frame, but only 10 times per second. Therefore, you can limit the frequency of their execution to improve performance.

Since each object should have its own tracker, you would probably want to store it in the script's state variable.

Functions	Description
new RateLimit(params: Object[])	Creates a RateLimit. interval is the interval in seconds between two triggers, for example, an interval of 0.1 means it should occur ten times per second.
RateLimit.shouldUpdate(): boolean	Has enough time elapsed between the last triggers? Wrap the necessary code using if (state.rateLimitXXX.shouldUpdate()) { … } to limit its execution frequency.
RateLimit.resetCoolDown(): void	Resets the timer to go off as soon as possible.

MTRClientData

Client data from MTR that can be used to read routes, transfers, etc. See the source code of MinecraftClientData.java from MTR.

MinecraftClient

Due to obfuscation, there is no way to directly provide a client class for use. Therefore, several helper methods are created:

Functions	Description
static MinecraftClient.worldIsRaining(): boolean	Is it raining in the world?
static MinecraftClient.worldIsThundering(): boolean	Is it thundering in the world?
static MinecraftClient.worldIsRainingAt(pos: Vector3f): boolean	Is it raining and getting wet in a given chunk?
static MinecraftClient.worldDayTime(): int	Returns the in-game world time in ticks.
static MinecraftClient.narrate(message: string): void	This calls the Minecraft narrator to narrate the message. [Not Implemented]
static MinecraftClient.displayMessage(message: String, actionBar: boolean): void	This displays the message as an in-game chat message. If action bar is true, it will display on the action bar instead. (Above inventory hotbar)