Lua Editor - Lumberyard User Guide

Lua Editor

This feature is in preview release and is subject to change.

Lumberyard Lua Editor (Lua IDE) offers an intuitive integrated development environment (IDE) that makes it easy to author, debug, and edit Lua scripts when you create or extend your game. Lua Editor is a standalone application, but can be opened directly from Lumberyard Editor.

Tutorial: Using Lua Editor for Debugging with Lumberyard Editor

This tutorial shows you how to use Lumberyard Editor to create a sample level with a component entity that contains a Lua script component. You open the script in Lua Editor from Lumberyard Editor and perform some sample debugging steps on the script.

To use Lua Editor for debugging

  1. In Lumberyard Editor, create a new level by performing one of the following steps:

    • In the Welcome to Lumberyard Editor window, click New level

    • Click File, New

    • Press Ctrl+N

  2. In the New Level dialog box, give the level a name, and then click OK.

  3. In the Generate Terrain Texture dialog box, click OK to accept the defaults.

  4. Right-click the Lumberyard Editor viewport and select Create Entity.

  5. In Entity Inspector, click Add Component, and then choose Rendering, Point Light.

  6. In Entity Inspector, click Add Component, and then choose Scripting, Lua Script.

  7. Scroll down to the bottom of the Entity Inspector window and, in the Lua Script section, click ... to open the Pick Lua Script window.

  8. In the Pick Lua Script window, expand Samples Project, Scripts,and Components.

  9. Click lightflicker.lua, and then click OK. (Note: additional sample scripts are located in the Lumberyard directory \dev\SamplesProject\Scripts.)

  10. In Entity Inspector, in the Lua Script section, click the empty braces { } to launch Lua Editor.

            Launch Lua Editor from Lumberyard Editor

    Because the debugging functionality is enabled through network sockets, you must connect Lua Editor to the target that is running the script before you can debug. In this tutorial, you connect to Lumberyard Editor.


    Connection is facilitated by Using GridHub, which is Lumberyard's central connection hub for debugging. GridHub starts automatically when Lua Editor is started and must be running in the background for Lua Editor to find targets it can connect to. If for some reason you need to start it manually, you can launch it from \dev\Bin64\LuaIDE.exe.

  11. In the Lua Editor toolbar, click Target: None, and then click Editor(ID) to connect to Lumberyard Editor.

            Target selector
  12. In the Lua Editor toolbar, leave Context setting at Default for the debugging context. The default setting is good for debugging component entity scripts such as the one in this tutorial. The Cry context option is for debugging legacy scripts such as those associated with Cry entities or the Game SDK.

            Context selector
  13. The Debugging icon turns green to show that Lua Editor and Lumberyard Editor are connected:

            Lua Editor connected to Lumberyard Editor

    Click Classes in the Class Reference to show the available Lua libraries. You can do the same for EBuses and Globals.

            Classes Reference

    The class reference feature is active only for the default context and component entity scripts. This feature is not active in the Cry context, which exists only for backward compatibility.

    After you connect, you can pause the execution of a given script by setting breakpoints.

  14. In the Lua Editor toolbar, click the Breakpoints icon to show the Breakpoints window.

  15. In Lua Editor, single-click or double-click one or more line numbers in the lightflicker.lua script to set one or more breakpoints. As you add breakpoints, the line number and script path for each are added to the Breakpoints window.

  16. In Lumberyard Editor, press Ctrl+G to run the game, or click AI/Physics at the bottom of the viewport to enable game simulation and run scripts. Lua Editor opens with a yellow marker stopped on the first breakpoint that it encounters.

            Debugger stopped on breakpoint

    When execution is halted at a breakpoint, more information becomes available in the Lua Locals, Stack, and Watched Variables panes.

  17. Click the Stack icon to show the Stack window.

  18. Click the Lua Locals icon to show local Lua variables.

  19. Click Watched Variables icon to open the Watched Variables window, where you can specify variables to watch.

  20. Press F11 a few times to step through the code. Note how the contents of the Stack, Lua Locals, and Watched Variables windows change.


    For greater convenience, you can float or dock these windows.

  21. To detach from debugging, click Debugging.

            Click to detach from debugging
            Debugging off
  22. In Lumberyard Editor, Press Esc to stop the game.

Options Available While Debugging

The following table summarizes common options available while debugging.

Icon Action Keyboard Shortcut Description
Run in Editor Alt+F5 Run in Lumberyard Editor.
Run on Target Ctrl+F5 Send script to the connected target and run it.
Run/Continue F5 Run or continue running the current script.
Step Into F11 Step into the function called on the current line.
Step Out Shift+F11 Step out of the called function.
Step Over F10 Step over the function called on the current line.
Toggle Breakpoint F9 Enable or disable a breakpoint on the current line.

Maintaining Separate Search Results

In addition to the usual search capabilities, the Find feature can display the results of four different searches separately.

To maintain separate search results

  1. Click the Find icon or press Ctrl+F to perform searches in the currently open file, or in all open files.

            Lua Editor Find dialog
  2. Before starting a search, choose Find 1, Find 2, Find 3, or Find 4 to choose the window in which you want to see the results. You can maintain the results of four searches separately in the tabbed windows. The search results in the other windows remain unchanged.

            Find Results
  3. To go directly to the line in the code which a search result was found, double-click the line in the search results.


    In Lua Editor Preview, the line number shown in the Find Results window and the line number in the script pane differ by one.


    For convenience, you can also dock or float the Find Results window.


Lua Editor can open multiple scripts at the same time. Each script has its own tab in the editor. The editor provides a standard set of capabilities for text editing but also includes useful features for editing source code.

The following table summarizes the options available while editing and debugging.

Action Keyboard Shortcut
Comment selected block Ctrl+K
Copy Ctrl+C
Cut Ctrl+X
Find Ctrl+F
Find in open files Ctrl+Shift+F
Find next F3
Fold source functions Alt+0
Go to line Ctrl+G
Paste Ctrl+V
Quick find local Ctrl+F3
Quick find local reverse Ctrl+Shift+F3
Redo Ctrl+Y
Replace Ctrl+R
Replace in open files Ctrl+Shift+R
Select all Ctrl+A

Select to brace¹

Transpose lines down Ctrl+Shift+Down Arrow
Transpose lines up Ctrl+Shift+Up Arrow
Uncomment selected block Ctrl+Shift+K
Undo Ctrl+Z
Unfold source functions Alt+Shift+0

¹ Select to brace selects a block bounded by braces. Before using this option, the cursor must be immediately next to the beginning or ending brace of the block.

Perforce Integration

Lua Editor includes Perforce integration features. When you open a file from your Perforce environment, Lua Editor displays the file's status in the top right of the text editing window.

        Not Checked Out

        Checked Out By You

The Source Control menu offers Check Out/Check In functionality.

        Source Control Menu