Difference between revisions of "LevelScripts"

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(Which level scripts to use in mods, and where to put files)
(Global level script: Added todo for level messages)
 
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== Overview ==
 +
[[Category: Modding]]
 +
[[Category:Overgrowth]]
 
Level scripts allow you to set up level-wide code that will get run, regardless of what characters, items, and hotspots exist in that level.
 
Level scripts allow you to set up level-wide code that will get run, regardless of what characters, items, and hotspots exist in that level.
 +
 +
Generally you should prefer to put your script logic in hotspots or character controller scripts.
 +
 +
However, sometimes a level script is the right tool for the job. This is especially true when you need to intercept messages that are only passed to level scripts, and that are not (by default) sent to smaller objects in the scene.
  
 
== Script Tiers ==
 
== Script Tiers ==
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The order that the engine calls into level scripts is as follows:
 
The order that the engine calls into level scripts is as follows:
  
==== level.as (in the file <code>Data/Scripts/level.as</code>) ====
+
==== Global level script ====
 +
This script file is located in <code>../Overgrowth/Data/Scripts/level.as</code>.
  
Only one of these scripts is ever active at a time, since it is either defined by the base game, or by a mod, and only one mod is allowed to be active at the same time that changes this file. The game will tell you "File Conflict Detected" if you try to activate a second mod that overrides the file.
+
Only one of these scripts is ever active at a time, since it is either defined by the base game, or by a mod, and only one mod is allowed to be active at the same time that changes this file. The game will tell you "File Collision" if you try to activate a second mod that overrides the file.
  
 
The engine will call into this script for every level in the game. You can override this script in mods, but it is best to only do this as a last resort, since this can make your mod incompatible with other script mods that also override the same file.
 
The engine will call into this script for every level in the game. You can override this script in mods, but it is best to only do this as a last resort, since this can make your mod incompatible with other script mods that also override the same file.
  
==== One script per-level (<code><script>some_dir/something.as</script></code>, defined by '''Edit -> Set Level Script...''') ====
+
'''TODO:''' These level messages are handled in this script, this should be documented somewhere:
 +
<pre>
 +
"clearhud"
 +
"cleartext"
 +
"disable_retry"
 +
"displaygui"
 +
"displayhud"
 +
"displaytext"
 +
"dispose_level"
 +
"go_to_main_menu"
 +
"loadlevel"
 +
"make_all_aware"
 +
"manual_reset"
 +
"open_menu"
 +
"reset"
 +
"screen_message"
 +
"start_dialogue"
 +
"start_dialogue_fade"
 +
"tutorial"
 +
</pre>
  
 +
==== Per-level script ====
 
Only one of these scripts is ever active at a time, since it is defined per-level, and you cannot have more than one level running at the same time.
 
Only one of these scripts is ever active at a time, since it is defined per-level, and you cannot have more than one level running at the same time.
  
The specific path for this script is found in the <code><script></code> XML tag inside each level XML file. This can be changed in the UI under '''Editor -> Top Bar -> Edit -> Set Level Script...'''.
+
The specific path for this script is found in the <code><script></code> XML tag inside each level XML file. This can be changed in the top bar in the editor under ''Edit -> Set Level Script...''.
  
You can override this script in your mods, but it requires you to make a per-level change, and only one such script can be active for a given level.
+
You can override this script in your mods, but that requires you to override it for each individual level. Only one such script can be active for a given level, so this is another place where mod collisions might occur.
  
==== One script per-mod (<code><LevelHookFile>some_dir/something.as</LevelHookFile></code>, inside each mod's mod.xml file ====
+
==== Per-mod Level Script ====
 +
Many of these scripts can be active at the same time, but each mod can only have one.
  
Many of these scripts can be active at the same time, though only one such script can be defined for each mod that you have active.
+
To use this script file you have to manually add the following XML tag the mod.xml that you make for your mod: <code><LevelHookFile>some_dir/something.as</LevelHookFile></code>
  
You have to manually add this XML tag the mod.xml that you make for your mod. Functions in this script are run for every level in the game, and every mod can add their own level hook script.
+
Functions in this script are run for every level in the game, and every mod can add their own level hook script.
  
 
The disadvantage to it is that you can't as easily override default level script behavior. For the most part, changes in this file are limited to adding on additional behavior, rather than altering existing behavior in the base level script.
 
The disadvantage to it is that you can't as easily override default level script behavior. For the most part, changes in this file are limited to adding on additional behavior, rather than altering existing behavior in the base level script.
Line 31: Line 60:
 
In mods, you should always strive to do the least impacting change possible. Prefer modifying level scripts in this order:
 
In mods, you should always strive to do the least impacting change possible. Prefer modifying level scripts in this order:
  
# per-mod level script
+
# [[#Per-mod_Level_Script|Per-mod level script]]
# per-level script
+
# [[#Per-level script|Per-level script]]
# Data/Scripts/level.as
+
# [[#Global level script|Global level script]]
 +
If you're creating a [[#Per-mod_Level_Script|per-mod level script]], then you have the most flexibility of where to put your script files. Still, it is best to follow a standard convention so that it is easier to find the scripts in other people's mods. The recommended location is <code>../Data/Mods/your_mod_name/Data/Scripts/your_mod_name/level_hook.as</code>.
 +
 
 +
If you're trying to alter existing script files, then you'll need to place your modified script files in more specific locations.
 +
 
 +
To override a [[#Per-level script|per-level script]] you must put your script file in <code>../Data/Mods/your_mod_dir/Data/Scripts/</code>, as this is the root directory for the <code><script></code> tag. To avoid accidentally overshadowing another mod's or one of the main game's script files, it is recommended that you create a directory in the <code>Scripts</code> directory with the name of your mod, and then put the script file in there. '''WARNING''': Right now there is a bug when setting a level script from the editor menu, if your script is in a <code>.../Data/Scripts/your_mod_name/</code> folder. You have to manually edit the <code>your_level.xml</code> file to change the script tag to <code><Script>your_mod_name/your_script_name.as</Script></code>
 +
 
 +
To overshadow the [[#Global level script|Global level script]], create your script file with the following directory and name: <code>../Data/Mods/your_mod_dir/Data/Scripts/level.as</code>.
 +
 
 +
== Documentation ==
 +
 
 +
A list of functions, data, etc, is created automatically whenever you run the game, in a file on your hard drive. This lists what external code you get "for free" and can call from inside a custom level script.
 +
 
 +
* '''Windows''': <code>My Documents\Wolfire\Overgrowth\aslevel_docs.h</code>
 +
* '''Mac''': <code>~/Library/Application Support/Overgrowth/aslevel_docs.h</code>
 +
* '''Linux''': <code>~/.local/share/Overgrowth/aslevel_docs.h</code>
 +
 
 +
This list is can change with each version of the game, so keep checking back on this <code>aslevel_docs.h</code> file to see the most up to date information.
 +
 
 +
There are also wiki pages which have more detailed documentation many of these functions. These pages have a danger of going out of date, but give more detailed documentation on some of the code:
 +
 
 +
* [[Level Script External Code|These functions are unique to level scripts]]
 +
* [[Common Script External Code|These functions are shared with other script types]]
 +
 
 +
== List of level script hook functions ==
 +
 
 +
These functions are '''required'''. You must include all of these functions in a level script:
 +
 
 +
* [[#Init function|<code>void Init(string level_name) { }</code>]]
  
If you're doing a per-mod level script, then you have the most flexibility of where you put your files. Still, it is best to follow a standard convention so that it is easier to find said script in other people's mods. Merlyn recommends:
+
These functions are '''optional'''. These functions do not have to be added to a level script, but will be called if they are present:
  
* <code>your_mod_name/Data/Scripts/your_mod_name/level_hook.as</code>
+
* [[#Update function|<code>void Update(int is_paused) { }</code>]]
 +
* [[#Update function|<code>void Update() { }  // Deprecated: Only called if previous function doesn't exist, and only when paused</code>]]
 +
* [[#ReceiveMessage function|<code>void ReceiveMessage(string message) { }</code>]]
 +
* [[#HotspotExit function|<code>void HotspotExit(string str, MovementObject @mo) { }</code>]]
 +
* [[#HotspotEnter function|<code>void HotspotEnter(string str, MovementObject @mo) { }</code>]]
 +
* [[#DrawGUI function|<code>void DrawGUI() { }</code>]]
 +
* [[#HasFocus function|<code>bool HasFocus() { return false; }</code>]]
 +
* [[#SetWindowDimensions function|<code>void SetWindowDimensions(int width, int height) { }</code>]]
 +
* [[#SaveHistoryState function|<code>void SaveHistoryState(SavedChunk@ chunk) { }</code>]]
 +
* [[#ReadChunk function|<code>void ReadChunk(SavedChunk@ chunk) { }</code>]]
 +
* [[#IncomingTCPData function|<code>void IncomingTCPData(uint socket, array<uint8>@ data) { }</code>]]
 +
* [[#DrawGUI2 function|<code>void DrawGUI2() { }</code>]]
 +
* [[#DrawGUI3 function|<code>void DrawGUI3() { }</code>]]
 +
* [[#DialogueCameraControl function|<code>bool DialogueCameraControl() { return false; }</code>]]
  
If you're trying to alter existing files, then you're more stuck.
+
== Documentation for level script hook functions ==
  
For an override for (<code><script>some_dir/something.as</script></code> (a per-level script) you must put your script file here:
+
=== Init function ===
  
* <code>your_mod_dir/Data/Scripts/some_dir/something.as</code>, with the specific directory dictated by the path defined in the level's XML file.
+
<pre style="white-space: pre-wrap;">void Init(string level_name) { }</pre>
  
For an override for <code>Data/Scripts/level.as</code> (replacing the base level script) you must put your script file here:
+
[[#List of level script hook functions|Required]]
  
* <code>your_mod_dir/Data/Scripts/level.as</code>
+
'''TODO''': Is level_name a filename, or a string description?
  
== Documentation ==
+
Called when the level is first loaded. '''TODO''': Is it called at any other time?
 +
 
 +
Be careful, this may be (often is) called before some objects or script params are present in the level!
 +
 
 +
It is most useful for setting initial values for file-scope angelscript state. '''TODO''': Good example of something that should be <code>Init</code> instead of just defined with a file-scope initializer?
 +
----
 +
 
 +
=== Update function ===
 +
 
 +
<pre style="white-space: pre-wrap;">void Update(int is_paused) { }</pre>
 +
 
 +
[[#List of level script hook functions|Optional]]
 +
 
 +
Called regularly by the engine so you can perform work, or detect that the game is paused. '''TODO''': Make example and add it here, or link to it.
 +
 
 +
It may be useful to do initialization once in this function, which is safer than doing it in Init if you need objects or level script params to be present. TODO: Make example and add it here, or link to it.
 +
 
 +
'''Note''': If <code>void Update(int is_paused) { }</code> is not present in the level script, then <code>void Update() { }</code> will be called instead (if present, but only if the game is paused). This is a deprecated fallback function, and it is recommended to always use the '''is_paused''' variant.
 +
----
 +
 
 +
=== ReceiveMessage function ===
 +
 
 +
<pre style="white-space: pre-wrap;">void ReceiveMessage(string message) { }</pre>
 +
 
 +
[[#List of level script hook functions|Optional]]
 +
 
 +
Called when level-wide messages have been sent by the engine, or by objects in levels.
 +
 
 +
Objects in levels (such as characters or hotspots) can send this using '''level.SendMessage("some message string");'''.
 +
 
 +
Parameters can be sent by separating them with spaces, and putting quotes around parameters that might contain spaces, then using the '''TokenIterator''' object.
 +
 
 +
'''TODO''': Make a good example and add it here, or link to it.
 +
----
 +
=== HotspotExit function ===
  
Documentation of the functions, classes, and object instances that you can access inside a level script are available in an automatically generated file on your hard drive:
+
<pre style="white-space: pre-wrap;">void HotspotExit(string str, MovementObject @mo) { }</pre>
  
# '''On Windows''': <code>My Documents\Wolfire\Overgrowth\aslevel_docs.h</code>
+
[[#List of level script hook functions|Optional]]
# '''On Mac''': <code>~/Library/Application Support/Overgrowth/aslevel_docs.h</code>
 
# '''On Linux''': <code>~/.local/share/Overgrowth/aslevel_docs.h</code>
 
  
The list of available functions, classes, and object instances can change with each version of the game, so keep checking back on this <code>aslevel_docs.h</code> file to see the most up to date information.
+
Triggered when any hotspot is exited by a movement object (such as a character, but not items).
  
== List of Data/Scripts/level.as hook functions ==
+
'''TODO''': Make a good example and add it here, or link to it.
 +
----
 +
=== HotspotEnter function ===
  
=== Required in Data/Scripts/level.as ===
+
<pre style="white-space: pre-wrap;">void HotspotEnter(string str, MovementObject @mo) { }</pre>
  
These functions are '''required''', and must be present in '''level.as'''. If you override that file in your mod, you must include all of these functions.
+
[[#List of level script hook functions|Optional]]
  
  void Init(string level_name) { }
+
Triggered when any hotspot is entered by a movement object (such as a character, but not items).
  // Called when the level is first loaded.
 
  // Be careful, this may be called before some objects or script params are present in the level.
 
  // It is most useful for setting initial values for file-scope angelscript state.
 
  
  void Update(int is_paused) { }
+
'''TODO''': Make a good example and add it here, or link to it.
  // Called regularly by the engine so you can perform work, or detect that the game is paused.
+
----
  // It may be useful to do initialization once in this function, if you need objects or level script params to be present.
+
=== DrawGUI function ===
  
  void ReceiveMessage(string message) { }
+
<pre style="white-space: pre-wrap;">void DrawGUI() { }</pre>
  // Called when level-wide messages have been sent by the engine, or by objects in levels.
 
  // Objects in levels (such as characters or hotspots) can send this using '''level.SendMessage("some message string");'''.
 
  // Parameters can be sent by separating them with spaces, and putting quotes around parameters that might contain spaces,
 
  //   then using the '''TokenIterator''' object.
 
  
  void HotspotExit(string str, MovementObject @mo) { }
+
[[#List of level script hook functions|Optional]]
  // Triggered when any hotspot is exited by a movement object
 
  
  void HotspotEnter(string str, MovementObject @mo) { }
+
An update function for script-defined GUIs and graphics/text overlays.
  // Triggered when any hotspot is entered by a movement object
 
  
  void DrawGUI() { }
+
<code>DrawGUI</code> is called after the main game scene is drawn. If you need to draw on top of other UIs that are drawn with <code>DrawGUI</code>, then see the <code>DrawGUI2</code> and <code>DrawGUI3</code> functions.
  // Serves as an update function for script-defined GUIs
 
  
  void SetWindowDimensions(int width, int height) { }
+
All level scripts will have their <code>DrawGUI</code> functions called before any level script's <code>DrawGUI2</code> or <code>DrawGUI3</code> function is called.
  // Allows a script-defined GUI to resize itself when the window gets resized
+
----
 +
=== HasFocus function ===
  
  void SaveHistoryState(SavedChunk@ chunk) { }
+
<pre style="white-space: pre-wrap;">bool HasFocus() { return false; }</pre>
  // Allows the level script to save extra undo state
 
  
  void ReadChunk(SavedChunk@ chunk) { }
+
[[#List of level script hook functions|Optional]]
  // Allows the level script to retrieve extra redo state
 
  
  bool HasFocus() { return false; }
+
Return true from this function if you are going to handle mouse input in this level script. This is particularly useful for menus that you draw yourself, such as the challenge level UI.
  // Old unused function.
 
  // Reserved, though, so be careful to just make this function return false, and not use it for anything
 
  
=== Optional in Data/Scripts/level.as ===
+
'''TODO''': Is this necessary with all types of UIs? How about Dear ImGui?
 +
----
 +
=== SetWindowDimensions function ===
  
These functions are '''optional''', but will be called if they are present in '''level.as'''.
+
<pre style="white-space: pre-wrap;">void SetWindowDimensions(int width, int height) { }</pre>
  
  void IncomingTCPData(uint socket, array<uint8>@ data) { }
+
[[#List of level script hook functions|Optional]]
  // Optional - Networking hook for when network data comes in over a socket you've created
 
  
  void DrawGUI2() { }
+
Allows a script-defined GUI to resize itself when the window gets resized.
  // Optional - A second pass for updating script-defined GUIs, in case you need to do something with two passes (e.g. layout)
+
----
 +
=== SaveHistoryState function ===
  
== List of per_level_script.as hook functions ==
+
<pre style="white-space: pre-wrap;">void SaveHistoryState(SavedChunk@ chunk) { }</pre>
  
Note that the specific path and filename of each of these scripts is defined in each level's XML file, and there can only be one such script defined per level.
+
[[#List of level script hook functions|Optional]]
  
=== Required in per_level_script.as ===
+
Allows the level script to save extra undo state.
  
These functions are '''required''', and must be present in <code><script>some_dir/per_level_script.as</script></code>. If you override that script file in your mod, or override the level file, you must include all of these functions.
+
'''TODO''': Document how this works and why it is useful.
 +
----
 +
=== ReadChunk function ===
  
  void Init(string level_name) { }
+
<pre style="white-space: pre-wrap;">void ReadChunk(SavedChunk@ chunk) { }</pre>
  // Called when the level is first loaded.
 
  // Be careful, this may be called before some objects or script params are present in the level.
 
  // It is most useful for setting initial values for file-scope angelscript state.
 
  
  void Update() { }
+
[[#List of level script hook functions|Optional]]
  // Called regularly by the engine so you can perform work.
 
  // This function '''will not be called''' if the game is paused.
 
  // It may be useful to do initialization once in this function, if you need objects or level script params to be present.
 
  
  void DrawGUI() { }
+
Allows the level script to retrieve extra redo state.
  // Serves as an update function for script-defined GUIs
 
  
  bool HasFocus() { return false; }
+
'''TODO''': Document how this works and why it is useful.
  // Old unused function.
+
----
  // Reserved, though, so be careful to just make this function return false, and not use it for anything
+
=== IncomingTCPData function ===
  
=== Optional in per_level_script.as ===
+
<pre style="white-space: pre-wrap;">void IncomingTCPData(uint socket, array<uint8>@ data) { }</pre>
  
These functions are '''optional''', but will be called if they are present in <code><script>some_dir/per_level_script.as</script></code>.
+
[[#List of level script hook functions|Optional]]
  
  void ReceiveMessage(string message) { }
+
Networking hook function, for when network data comes in over a socket you've created.
  // Called when level-wide messages have been sent by the engine, or by objects in levels.
 
  // Objects in levels (such as characters or hotspots) can send this using '''level.SendMessage("some message string");'''.
 
  // Parameters can be sent by separating them with spaces, and putting quotes around parameters that might contain spaces,
 
  //  then using the '''TokenIterator''' object.
 
  
  void IncomingTCPData(uint socket, array<uint8>@ data) { }
+
'''TODO''': Add better documentation for this function, or link to another page with better documentation.
  // Optional - Networking hook for when network data comes in over a socket you've created
+
----
  
  void DrawGUI2() { }
+
=== DrawGUI2 function ===
  // Optional - A second pass for updating script-defined GUIs, in case you need to do something with two passes (e.g. layout)
 
  
== List of per_mod_script.as hook functions ==
+
<pre style="white-space: pre-wrap;">void DrawGUI2() { }</pre>
  
Note that the specific path and filename of each of these scripts is defined in each mod's mod.xml file, and there can only be one such script defined per mod.
+
[[#List of level script hook functions|Optional]]
  
=== Required in per_mod_script.as ===
+
A second pass for updating script-defined GUIs and graphics/text overlays, in case you need to do something with two passes (e.g. windows and text overlays that should always be on top of other windows/dialogues, etc).
  
These functions are '''required''', and must be present in <code><LevelHookFile>some_dir/something.as</LevelHookFile></code>.
+
<code>DrawGUI2</code> is called after <code>DrawGUI</code>, in case you need to draw on top of other UIs at those levels.
If you add this level hook script in your mod, you must include all of these functions.
 
  
  void Init(string level_name) { }
+
All level scripts will have their <code>DrawGUI</code> functions called before any level script's <code>DrawGUI2</code> function is called. All level script's <code>DrawGUI2</code> functions will be called before any level script's <code>DrawGUI3</code> gets called.
  // Called when the level is first loaded.
+
----
  // Be careful, this may be called before some objects or script params are present in the level.
+
=== DrawGUI3 function ===
  // It is most useful for setting initial values for file-scope angelscript state.
 
  
  void Update(int is_paused) { }
+
<pre style="white-space: pre-wrap;">void DrawGUI3() { }</pre>
  // Called regularly by the engine so you can perform work, or detect that the game is paused.
 
  // It may be useful to do initialization once in this function, if you need objects or level script params to be present.
 
  
  void DrawGUI() { }
+
[[#List of level script hook functions|Optional]]
  // Serves as an update function for script-defined GUIs
 
  
  void SetWindowDimensions(int width, int height) { }
+
A third pass for updating script-defined GUIs and graphics/text overlays, in case you need to do something with three passes (e.g. windows that are always top level, such as the pause menu).
  // Allows a script-defined GUI to resize itself when the window gets resized
 
  
=== Optional in per_mod_script.as ===
+
<code>DrawGUI3</code> is called after <code>DrawGUI2</code> and <code>DrawGUI</code>, in case you need to draw on top of other UIs at those levels.
  
These functions are '''optional''', but will be called if they are present in <code><LevelHookFile>some_dir/something.as</LevelHookFile></code>.
+
All level scripts will have their <code>DrawGUI</code> and <code>DrawGUI2</code> functions called before any level script's <code>DrawGUI3</code> function is called.
 +
----
 +
=== DialogueCameraControl function ===
  
  void ReceiveMessage(string message) { }
+
<pre style="white-space: pre-wrap;">bool DialogueCameraControl() { return false; }</pre>
  // Called when level-wide messages have been sent by the engine, or by objects in levels.
 
  // Objects in levels (such as characters or hotspots) can send this using '''level.SendMessage("some message string");'''.
 
  // Parameters can be sent by separating them with spaces, and putting quotes around parameters that might contain spaces,
 
  //   then using the '''TokenIterator''' object.
 
  
  void IncomingTCPData(uint socket, array<uint8>@ data) { }
+
[[#List of level script hook functions|Optional]]
  // Optional - Networking hook for when network data comes in over a socket you've created
 
  
  void DrawGUI2() { }
+
Called from character scripts, in order to determine if a dialogue rendered in a level script has camera control. That way character control scripts can avoid conflicts while they manipulate the camera.
  // Optional - A second pass for updating script-defined GUIs, in case you need to do something with two passes (e.g. layout)
 

Latest revision as of 07:31, 7 April 2018

Overview

Level scripts allow you to set up level-wide code that will get run, regardless of what characters, items, and hotspots exist in that level.

Generally you should prefer to put your script logic in hotspots or character controller scripts.

However, sometimes a level script is the right tool for the job. This is especially true when you need to intercept messages that are only passed to level scripts, and that are not (by default) sent to smaller objects in the scene.

Script Tiers

The order that the engine calls into level scripts is as follows:

Global level script

This script file is located in ../Overgrowth/Data/Scripts/level.as.

Only one of these scripts is ever active at a time, since it is either defined by the base game, or by a mod, and only one mod is allowed to be active at the same time that changes this file. The game will tell you "File Collision" if you try to activate a second mod that overrides the file.

The engine will call into this script for every level in the game. You can override this script in mods, but it is best to only do this as a last resort, since this can make your mod incompatible with other script mods that also override the same file.

TODO: These level messages are handled in this script, this should be documented somewhere:

"clearhud"
"cleartext"
"disable_retry"
"displaygui"
"displayhud"
"displaytext"
"dispose_level"
"go_to_main_menu"
"loadlevel"
"make_all_aware"
"manual_reset"
"open_menu"
"reset"
"screen_message"
"start_dialogue"
"start_dialogue_fade"
"tutorial"

Per-level script

Only one of these scripts is ever active at a time, since it is defined per-level, and you cannot have more than one level running at the same time.

The specific path for this script is found in the <script> XML tag inside each level XML file. This can be changed in the top bar in the editor under Edit -> Set Level Script....

You can override this script in your mods, but that requires you to override it for each individual level. Only one such script can be active for a given level, so this is another place where mod collisions might occur.

Per-mod Level Script

Many of these scripts can be active at the same time, but each mod can only have one.

To use this script file you have to manually add the following XML tag the mod.xml that you make for your mod: <LevelHookFile>some_dir/something.as</LevelHookFile>

Functions in this script are run for every level in the game, and every mod can add their own level hook script.

The disadvantage to it is that you can't as easily override default level script behavior. For the most part, changes in this file are limited to adding on additional behavior, rather than altering existing behavior in the base level script.

Which level scripts to use in mods, and where to put files

In mods, you should always strive to do the least impacting change possible. Prefer modifying level scripts in this order:

  1. Per-mod level script
  2. Per-level script
  3. Global level script

If you're creating a per-mod level script, then you have the most flexibility of where to put your script files. Still, it is best to follow a standard convention so that it is easier to find the scripts in other people's mods. The recommended location is ../Data/Mods/your_mod_name/Data/Scripts/your_mod_name/level_hook.as.

If you're trying to alter existing script files, then you'll need to place your modified script files in more specific locations.

To override a per-level script you must put your script file in ../Data/Mods/your_mod_dir/Data/Scripts/, as this is the root directory for the <script> tag. To avoid accidentally overshadowing another mod's or one of the main game's script files, it is recommended that you create a directory in the Scripts directory with the name of your mod, and then put the script file in there. WARNING: Right now there is a bug when setting a level script from the editor menu, if your script is in a .../Data/Scripts/your_mod_name/ folder. You have to manually edit the your_level.xml file to change the script tag to <Script>your_mod_name/your_script_name.as</Script>

To overshadow the Global level script, create your script file with the following directory and name: ../Data/Mods/your_mod_dir/Data/Scripts/level.as.

Documentation

A list of functions, data, etc, is created automatically whenever you run the game, in a file on your hard drive. This lists what external code you get "for free" and can call from inside a custom level script.

  • Windows: My Documents\Wolfire\Overgrowth\aslevel_docs.h
  • Mac: ~/Library/Application Support/Overgrowth/aslevel_docs.h
  • Linux: ~/.local/share/Overgrowth/aslevel_docs.h

This list is can change with each version of the game, so keep checking back on this aslevel_docs.h file to see the most up to date information.

There are also wiki pages which have more detailed documentation many of these functions. These pages have a danger of going out of date, but give more detailed documentation on some of the code:

List of level script hook functions

These functions are required. You must include all of these functions in a level script:

These functions are optional. These functions do not have to be added to a level script, but will be called if they are present:

Documentation for level script hook functions

Init function

void Init(string level_name) { }

Required

TODO: Is level_name a filename, or a string description?

Called when the level is first loaded. TODO: Is it called at any other time?

Be careful, this may be (often is) called before some objects or script params are present in the level!

It is most useful for setting initial values for file-scope angelscript state. TODO: Good example of something that should be Init instead of just defined with a file-scope initializer?


Update function

void Update(int is_paused) { }

Optional

Called regularly by the engine so you can perform work, or detect that the game is paused. TODO: Make example and add it here, or link to it.

It may be useful to do initialization once in this function, which is safer than doing it in Init if you need objects or level script params to be present. TODO: Make example and add it here, or link to it.

Note: If void Update(int is_paused) { } is not present in the level script, then void Update() { } will be called instead (if present, but only if the game is paused). This is a deprecated fallback function, and it is recommended to always use the is_paused variant.


ReceiveMessage function

void ReceiveMessage(string message) { }

Optional

Called when level-wide messages have been sent by the engine, or by objects in levels.

Objects in levels (such as characters or hotspots) can send this using level.SendMessage("some message string");.

Parameters can be sent by separating them with spaces, and putting quotes around parameters that might contain spaces, then using the TokenIterator object.

TODO: Make a good example and add it here, or link to it.


HotspotExit function

void HotspotExit(string str, MovementObject @mo) { }

Optional

Triggered when any hotspot is exited by a movement object (such as a character, but not items).

TODO: Make a good example and add it here, or link to it.


HotspotEnter function

void HotspotEnter(string str, MovementObject @mo) { }

Optional

Triggered when any hotspot is entered by a movement object (such as a character, but not items).

TODO: Make a good example and add it here, or link to it.


DrawGUI function

void DrawGUI() { }

Optional

An update function for script-defined GUIs and graphics/text overlays.

DrawGUI is called after the main game scene is drawn. If you need to draw on top of other UIs that are drawn with DrawGUI, then see the DrawGUI2 and DrawGUI3 functions.

All level scripts will have their DrawGUI functions called before any level script's DrawGUI2 or DrawGUI3 function is called.


HasFocus function

bool HasFocus() { return false; }

Optional

Return true from this function if you are going to handle mouse input in this level script. This is particularly useful for menus that you draw yourself, such as the challenge level UI.

TODO: Is this necessary with all types of UIs? How about Dear ImGui?


SetWindowDimensions function

void SetWindowDimensions(int width, int height) { }

Optional

Allows a script-defined GUI to resize itself when the window gets resized.


SaveHistoryState function

void SaveHistoryState(SavedChunk@ chunk) { }

Optional

Allows the level script to save extra undo state.

TODO: Document how this works and why it is useful.


ReadChunk function

void ReadChunk(SavedChunk@ chunk) { }

Optional

Allows the level script to retrieve extra redo state.

TODO: Document how this works and why it is useful.


IncomingTCPData function

void IncomingTCPData(uint socket, array<uint8>@ data) { }

Optional

Networking hook function, for when network data comes in over a socket you've created.

TODO: Add better documentation for this function, or link to another page with better documentation.


DrawGUI2 function

void DrawGUI2() { }

Optional

A second pass for updating script-defined GUIs and graphics/text overlays, in case you need to do something with two passes (e.g. windows and text overlays that should always be on top of other windows/dialogues, etc).

DrawGUI2 is called after DrawGUI, in case you need to draw on top of other UIs at those levels.

All level scripts will have their DrawGUI functions called before any level script's DrawGUI2 function is called. All level script's DrawGUI2 functions will be called before any level script's DrawGUI3 gets called.


DrawGUI3 function

void DrawGUI3() { }

Optional

A third pass for updating script-defined GUIs and graphics/text overlays, in case you need to do something with three passes (e.g. windows that are always top level, such as the pause menu).

DrawGUI3 is called after DrawGUI2 and DrawGUI, in case you need to draw on top of other UIs at those levels.

All level scripts will have their DrawGUI and DrawGUI2 functions called before any level script's DrawGUI3 function is called.


DialogueCameraControl function

bool DialogueCameraControl() { return false; }

Optional

Called from character scripts, in order to determine if a dialogue rendered in a level script has camera control. That way character control scripts can avoid conflicts while they manipulate the camera.