TypeScript API

This page gives an overview over the functionality that ez exposes through TypeScript. For an introduction to the TypeScript language please refer to the web (for example TypeScript in 5 minutes).

Note that you don’t need to install anything to use TypeScript in ez, the required TypeScript transpiler is already included.

API Documentation

All TypeScript APIs are documented with code comments. In Visual Studio Code you can see the documentation for each function by hovering the mouse cursor over it:

Function documentation

You can also jump to a function or class declaration using F12. This is useful to see what functions are available on a given class.

Importing Files (require)

TypeScript and JavaScript have multiple mechanisms how to make code from other files available. In ez only the require mechanism will work:

import ez = require("TypeScript/ez")

This imports all exported declarations from the file TypeScript/ez.ts into an object called ez in this file. Thus typing ez. grants access to all the exported classes, namespaces and functions from that file.

The path given to require must be relative to a data directory. For example, the file above is located in the Plugins data directory.

Note:

require always returns an object and therefore you must assign its result to a variable. Consequently, there is no way to make the imported names globally accessible, you can only access them through that variable.

To import multiple files, you need to store each result in a different variable:

import ez = require("TypeScript/ez")
import _ge = require("Scripting/GameEnums")

Re-exporting Imported Declarations

You can re-export declarations from a .ts file that you imported from somewhere else. For plenty of examples, look at the file ez.ts:

import __Log = require("TypeScript/ez/Log")
export import Log = __Log.Log;

Here, everything from the file Log.ts is imported into the variable __Log. We then selectively re-export the namespace Log from the variable __Log again, under the name Log. We could rename the exported symbol, if we wanted.

Unfortunately, there does not seem to be a way to re-export all declarations automatically, you need to name each one individually.

Scenegraph

ez.Component

ez.Component is the base class for all component types, including the C++ components. Your custom components must extend either ez.TypescriptComponent or ez.TickedTypescriptComponent.

The functionality exposed through ez.Component is mostly identical to all other components.

If you hold a reference to a component for more than a frame, it is vital to use ez.Component.IsValid() to check whether the component is still alive, before accessing it. If IsValid() returns true, the component can be accessed safely for the rest of the frame.

ez.GameObject

ez.GameObject exposes the game object functionality to TypeScript mostly 1:1. Through this you modify object positions, delete or move child nodes, access attached components and send messages.

You can’t extend game objects.

If you hold a reference to a game object for more than a frame, it is vital to use ez.GameObject.IsValid() to check whether it is still alive, before accessing it. If IsValid() returns true, the game object can be accessed safely for the rest of the frame.

ez.World

ez.World exposes the world functionality. However, the functionality provided is only a limited subset. Some functionality is simply not needed in the TypeScript binding, and some is exposed differently.

Since all TypeScript code is executed in the context of one specific world, you can’t access a different world from TypeScript code. Therefore, there is no need to get the world that you operate in (as is common in C++). Therefore ez.World is only a namespace, not a class, and all functionality is always accessible.

Additionally, functionality like ez.Clock and ez.Random, which are in C++ bound directly to a world, are similarly just global namespaces in TypeScript and not exposed through ez.World.

ez.Message

ez.Message and ez.EventMessage are base classes for all messages. The page Messaging in TypeScript Code goes into more detail.

Math

TypeScript already provides mathematical functions through the Math namespace. Additionally, the ez API provides these classes:

Debugging

ez.Log

The ez.Log namespace contains functions for writing messages to the log. This is a useful tool for debugging.

ez.Debug

The ez.Debug namespace contains various functionality. There are functions for debug rendering, ie. to insert shapes into the rendered output, which can be helpful in visualizing many aspects. ez.Debug also provides access to CVars and console functions.

Utilities

ez.Clock

The ez.Clock namespace has functions to access the world’s clock. The clock represents the game time, meaning it advances at its own pace, which can be adjusted dynamically. When you need to know how much time has passed since the last frame (not the last Tick()), use ez.Clock.GetTimeDiff(). Use ez.Clock.GetAccumulatedTime() it you need to measure longer durations.

ez.Time

In TypeScript code time should be stored as number types and measured in seconds. This is how all functions expect time values. ez.Time contains utility functions to convert time values to other units and to query the current system time.

ez.Random

The ez.Random namespace contains functions to get random numbers.

Physics

In ez.Physics you find functions to query the physics engine. For example to do raycasts or overlap tests.

See Also