Resource Loading API

The Resource Loading API allows you to read assets within resource packs, such as json, images or fonts via scripting.

Identifier (a.k.a. ResourceLocation)

Minecraft uses an Identifier to identify files in a resource pack, thus many functions only accept Identifier rather than strings.
To create an Identifier, you can use the following functions:

Functions	Description
static Resources.id(idStr: String): Identifier	Create an Identifier based on the string e.g. Resources.id(“mtr:path/absolute.js”).
static Resources.idr(relPath: String): Identifier	Create an Identifier based on the relative directory the currently executed script are located in e.g. Resources.idr(“relative.js”). Note: This function must be used during the script parsing stage. It cannot be used in runtime as by then there's no reference to the current script location anymore.

Resources

This class allows developers to access file contents within resource packs, as well as some utilities functions for obtaining AWT resources such as Font.

Note

Reading resources from the disk is rather slow compared to other in-memory operations. Reading it every frame (i.e. in render()) may cause significant lag issues depending on the resources.

If the resources (Image/Text/Whatever) you want to read is known ahead of time, you should read it and save it to a variable during the Parsing Stage, so you can re-use the content during the runtime stage.

Resource Reading

Functions	Description
static Resources.read(id: Identifier): DataReader?	Read an asset/file in the resource pack based on the Identifier location. Returns a DataReader to read the file's content. Null if the file does not exist.
static Resources.exist(id: Identifier): boolean	Returns whether the specified file exist in the resource pack.

Show deprecated fields/functions

These functions are kept for backward compatibility, before the introduction of a unified Data Reading API.
You are advised to avoid using these functions for newly created scripts.

Functions	Description
static Resources.manager(): null	Returns Minecraft's native resource manager in NTE. Since it is not exposed in Minecraft-Mappings (MTR 4's cross-version framework), this now returns null. Other functions that require Resources.manager() can accept null without any issues.
static Resources.readString(id: Identifier): String?	Reads the contents of a resource file as a string. Null if the file reading failed.
static Resources.readBufferedImage(id: Identifier): BufferedImage?	Loads an image file as an AWT BufferedImage. Null if the file reading failed.
static Resources.readFont(id: Identifier): Font?	Load a custom TTF or OTF font file as an AWT Font. Null if the file reading failed. Note: Due to the way Java and Minecraft Resource Pack works, new temporary font files are generated on your disk every time you call this function. If you find yourself running out of disk space during the development, you can free up disk space by deleting files starting with +~JF on your system temp directory, or restart your Minecraft/Computer.

AWT related

AWT is a window toolkit for Java. While not used directly in Minecraft, many of it's classes are still in-use (Such as BufferedImage/AWT Graphics) for cross-platform graphics processing/canvas. This is also used to power the Graphics API.

Here, you may obtain instances that may be useful for drawing with the Graphics API/AWT.

Functions	Description
static Resources.getSystemFont(name: String): Font	Get a system or MTR built-in AWT font. name can be one of the following: - Noto Serif: MTR's built-in CJK serif font (similar to Song), identical on all systems. - Noto Sans Semibold: MTR's built-in sans-serif font (Similar to Myriad Pro). - Noto Sans CJK TC Medium: JCM's built-in sans-serif CJK font (similar to Helvetica). Identical on all systems. Identical on all systems. - Noto Sans: [Deprecated] Alias of Noto Sans CJK TC Medium (above font). For NTE compatibility only! - Serif: A serif font selected by AWT that is installed on this computer. Varies between devices. - SansSerif: A sans serif font selected by AWT that is installed on this computer. Varies between devices. - Monospaced: A monospaced font selected by AWT that is installed on this computer. Varies between devices
static Resources.getFontRenderContext(): FontRenderContext	Obtain an AWT FontRenderContext for dimension measurement of text.
static Resources.ensureStrFonts(text: String, primaryFont: Font, fallbackFonts: Font...): AttributedString	Get an instance of AttributedString with the corresponding text and font set. primaryFont is the default font used. If the primary font cannot render a certain character, it will iterate over fallbackFonts (If there are any) and check whether the font is capable of rendering the characters. If not, it will iterate through the fonts available in the user's computer until a suitable one can be found. This is useful to prevent Tofu/Square when rendering versatile scripts (Such as Arabic on a Latin font).