Animation-LuaScripting

Getting started

Setup

Lua unit animation is implemented partially in the engine, and partially in a Lua gadget which is shipped with Spring in springcontent.sdz. By default, gadget is not loaded, so a bit of setup is required to enable Lua unit scripts. (In some games, gadget is alredy activated, for example in Zero:k)

To enable Lua unit scripts, create a file LuaRules/Gadgets/unit_script.lua, and paste the following into it:

-- Enables Lua unit scripts by including the gadget from springcontent.sdz -- Uncomment to override the directory which is scanned for *.lua unit scripts. --UNITSCRIPT_DIR = "scripts/" return include("LuaGadgets/Gadgets/unit_script.lua")

Also, do check whether your LuaRules/system.lua is up to date, if you copied this verbatim into your game. (Must be from a later date than 5 september 2009)

Now this is done, you can start putting *.lua files in your scripts/ folder.

Workflow

Lua has the major advantage over BOS/COB that you do not need to compile it, which can reduce the time to develop scripts quite a bit.

To save further time, do not restart Spring for each small change. Simply run Spring in an window so you can easily switch between your editor and Spring, and use /cheat and /luarules reload to reload all Lua unit scripts.

To be able to use commands above, unzip your game into directory named "myGame.sdd", then you can directly change lua scripts (animations etc.) and reload.

Additionally, for Lua unit scripts operating on Assimp models (primarily .dae and .blend), it is possible to do most of your animating in Blender using the blender2lus export addon.

Further reading

• Stumpy tutorial
• Polishing the stumpy
• Animation-LuaCallins
• Animation-LuaCallouts
• comparing Lua and COB unit scripts
• SpringTutorialGame contains simple examples unit scripts
• SpringRtsTutorialAnimDef examples animation scripts

TODO

• Conversion tool
• Performance measurements
• Link to article in piro's magazine
• Coordinate system (axis, direction of rotation, picture)