Frictional Wiki - User contributions [en]

HPL3/Areas/Ladder Area

2021-03-10T18:16:23Z

M654: Created page with "== Overview == When placed on a static object (like a ladder), the Ladder area will allow the player to climb it. == Properties == === Material === Determines the type of sou..."

== Overview ==
When placed on a static object (like a ladder), the Ladder area will allow the player to climb it.

== Properties ==
=== Material ===
Determines the type of sounds the player will make when climbing.

=== Exit_Top ===
[[Image:Ladder.png|thumb|A functioning ladder setup. Light green = Ladder, blue = InteractAux, red = Trigger|right]]
The [[HPL3/Areas/Trigger Area|Trigger area]] where the player will end up when exiting the ladder from the top. In order to work properly, an [[HPL3/Areas/InteractAux Area|InteractAux area]] with its '''InteractParent''' property set to the Ladder area must be placed next to the Trigger area, as seen in the image.

=== Exit_Bottom ===
Same as '''Exit_Top''' but for exiting from the bottom.

File:Ladder.png

2021-03-10T18:13:52Z

M654:

File:Hpl3:LadderArea.png

2021-03-10T18:12:15Z

M654:

HPL3/Areas/PlayerStart Area

2021-03-10T18:05:21Z

M654: Created page with "As the name implies, the PlayerStart area is where the player will spawn when the map is loaded."

As the name implies, the PlayerStart area is where the player will spawn when the map is loaded.

HPL3/Areas/Trigger Area

2021-03-10T17:54:02Z

M654: Created page with "== Overview == The Trigger area runs a callback function when an entity collides with it. == Properties == === CC_Entities === This is a list of all entities that can trigger..."

== Overview ==
The Trigger area runs a callback function when an entity collides with it.

== Properties ==
=== CC_Entities ===
This is a list of all entities that can trigger the callback, separated by commas or spaces. <code>player</code> refers to the player character.

=== CC_Funcs ===
Includes a list of functions that will run when the area is triggered.

== Callback function syntax ==
This is the basic syntax for a collision callback function.
<syntaxhighlight lang="cpp">
bool FunctionName(const tString &in asParent, const tString &in asChild, int alState)
{
if(alState == 1) // 1 = entering area, -1 = leaving area
{
// Insert code here
}
return false;
}
</syntaxhighlight>

HPL3/Amnesia: Rebirth/Tutorials/Inventory items

2020-11-12T16:22:44Z

M654: Fixed images

This tutorial will explain how to create a custom item that can be picked up, added to the inventory, and used on other entities.

[[Image:CustomItemExample2.jpg|thumb|An example of a custom item in the inventory|right]]

==Tutorial==

===Creating an ItemType===
Let's start by creating an item type. Keep in mind that an ItemType isn't the same as the physical in-game item entity, so a single ItemType can be used with multiple different entities.

Open <code>config/Inventory.cfg</code>. This file contains a list of all ItemTypes in the game. Add a new <code><ItemType></code> tag:
<syntaxhighlight lang="xml">
<ItemType ID="ItemName">
<Inventory Icon="icon_file_name"/>
<Use OnWorld="true" CanUseOnWorldMapCallback="CanUse_ItemName" UseOnWorldMapCallback="OnUse_ItemName"/>
</ItemType>
</syntaxhighlight>

The icons for items shown in the inventory are stored in <code>graphics/inventory/items</code> and saved in the DDS format. Replace <code>icon_file_name</code> with the name of your icon file, and change <code>ItemName</code> to whatever you want to call your item type.

Setting the <code>OnWorld</code> attribute to <code>true</code> will allow this item
type to be used on other entities in-game.

<code>CanUseOnWorldMapCallback</code> and <code>UseOnWorldMapCallback</code> are functions that determine which entities the item type can interact with and what happens when it's used on an entity, respectively. We'll get back to these later.

A detailed list of Use attributes and available functions is located in the beginning of <code>Inventory.cfg</code>, but to keep things simple we'll only be using the three shown above.

===Item name and description===
Now let's give the item a name and a description that will show up when the item is moused over in the inventory. Open <code>config/lang/english.lang</code> and add two entries to the <code>Inventory</code> category: <code>ItemName</code> and <code>ItemName_Desc</code>.

<syntaxhighlight lang="xml">
<LANGUAGE>
<CATEGORY Name="Inventory">
<Entry Name="ItemName">Test Item</Entry>
<Entry Name="ItemName_Desc">This is a simple test item.</Entry>
</CATEGORY>
</LANGUAGE>
</syntaxhighlight>

===Placing the entity===
[[Image:CustomItemEntityTab.png|thumb|The Entity tab|right]]
In the level editor, choose an entity to represent the item in-game. Select it, open its '''Entity''' tab and look for a section called '''Pickup'''. If it isn't there, that means that the entity is either a physics object or a static object and you won't be able to pick it up in-game. In that case, open the entity's ENT file, scroll down to the <code><UserDefinedVariables></code> tag and change the <code>EntityType</code> attribute to <code>Prop_Pickup</code>:

<syntaxhighlight lang="xml">
<UserDefinedVariables EntityType="Prop_Pickup">
</syntaxhighlight>

Now re-add the entity to the map. The '''Pickup''' section should now appear. Expand the section and set the ItemType attribute to the ID of the item type you created in <code>Inventory.cfg</code>. Now, when you click on the item in-game it will be added to your inventory.

===Item scripting===
Open the map script and add a new function called <code>CanUse_ItemName</code>:

<syntaxhighlight lang="cpp">
bool CanUse_ItemName(const tString &in asItemType, const tString &in asItemID, const tString &in asPickedEntity)
{
if(asPickedEntity == "ExampleEntity1" || asPickedEntity == "ExampleEntity2")
{
return true;
}
return false;
}
</syntaxhighlight>

This is one of the functions we set in the config file, and it determines which entities the item can interact with. The <code>asPickedEntity</code> parameter contains the name of the entity the player is looking at at any given time. If the function returns <code>true</code>, the player can use the item on the picked entity. In this example, the function returns <code>true</code> if the picked entity is named <code>ExampleEntity1</code> or <code>ExampleEntity2</code> (ie. the player can use the item on either of these entities).

Finally, let's add one more function.

<syntaxhighlight lang="cpp">
bool OnUse_ItemName(const tString &in asItemType, const tString &in asItemID, const tString &in asTargetEntity, const tString &in asItemEntity, float afTimeElapsed, float afTimeStep)
{
if(asTargetEntity == "ExampleEntity1")
{
// Insert code to interact with ExampleEntity1
}
else if(asTargetEntity == "ExampleEntity2")
{
// Insert code to interact with ExampleEntity2
}

return false;
}
</syntaxhighlight>
This code runs when the player clicks on an entity while holding the item. As shown above, this time the name of the clicked entity is stored in <code>asTargetEntity</code>.

[[Image:CustomItemExample3_reupload.jpg|thumb|Picking up the test item|left]]
[[Image:CustomItemExample4_reupload.jpg|thumb|Using the test item on a door entity|left]]

File:CustomItemExample3 reupload.jpg

2020-11-12T16:22:10Z

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File:CustomItemExample4 reupload.jpg

2020-11-12T16:21:34Z

M654: M654 uploaded a new version of File:CustomItemExample4 reupload.jpg

File:CustomItemExample4 reupload.jpg

2020-11-12T16:20:21Z

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HPL3/Amnesia: Rebirth/Tutorials/Inventory items

2020-11-12T16:15:17Z

M654:

This tutorial will explain how to create a custom item that can be picked up, added to the inventory, and used on other entities.

[[Image:CustomItemExample2.jpg|thumb|An example of a custom item in the inventory|right]]

==Tutorial==

===Creating an ItemType===
Let's start by creating an item type. Keep in mind that an ItemType isn't the same as the physical in-game item entity, so a single ItemType can be used with multiple different entities.

Open <code>config/Inventory.cfg</code>. This file contains a list of all ItemTypes in the game. Add a new <code><ItemType></code> tag:
<syntaxhighlight lang="xml">
<ItemType ID="ItemName">
<Inventory Icon="icon_file_name"/>
<Use OnWorld="true" CanUseOnWorldMapCallback="CanUse_ItemName" UseOnWorldMapCallback="OnUse_ItemName"/>
</ItemType>
</syntaxhighlight>

The icons for items shown in the inventory are stored in <code>graphics/inventory/items</code> and saved in the DDS format. Replace <code>icon_file_name</code> with the name of your icon file, and change <code>ItemName</code> to whatever you want to call your item type.

Setting the <code>OnWorld</code> attribute to <code>true</code> will allow this item
type to be used on other entities in-game.

<code>CanUseOnWorldMapCallback</code> and <code>UseOnWorldMapCallback</code> are functions that determine which entities the item type can interact with and what happens when it's used on an entity, respectively. We'll get back to these later.

A detailed list of Use attributes and available functions is located in the beginning of <code>Inventory.cfg</code>, but to keep things simple we'll only be using the three shown above.

===Item name and description===
Now let's give the item a name and a description that will show up when the item is moused over in the inventory. Open <code>config/lang/english.lang</code> and add two entries to the <code>Inventory</code> category: <code>ItemName</code> and <code>ItemName_Desc</code>.

<syntaxhighlight lang="xml">
<LANGUAGE>
<CATEGORY Name="Inventory">
<Entry Name="ItemName">Test Item</Entry>
<Entry Name="ItemName_Desc">This is a simple test item.</Entry>
</CATEGORY>
</LANGUAGE>
</syntaxhighlight>

===Placing the entity===
[[Image:CustomItemEntityTab.png|thumb|The Entity tab|right]]
In the level editor, choose an entity to represent the item in-game. Select it, open its '''Entity''' tab and look for a section called '''Pickup'''. If it isn't there, that means that the entity is either a physics object or a static object and you won't be able to pick it up in-game. In that case, open the entity's ENT file, scroll down to the <code><UserDefinedVariables></code> tag and change the <code>EntityType</code> attribute to <code>Prop_Pickup</code>:

<syntaxhighlight lang="xml">
<UserDefinedVariables EntityType="Prop_Pickup">
</syntaxhighlight>

Now re-add the entity to the map. The '''Pickup''' section should now appear. Expand the section and set the ItemType attribute to the ID of the item type you created in <code>Inventory.cfg</code>. Now, when you click on the item in-game it will be added to your inventory.

===Item scripting===
Open the map script and add a new function called <code>CanUse_ItemName</code>:

<syntaxhighlight lang="cpp">
bool CanUse_ItemName(const tString &in asItemType, const tString &in asItemID, const tString &in asPickedEntity)
{
if(asPickedEntity == "ExampleEntity1" || asPickedEntity == "ExampleEntity2")
{
return true;
}
return false;
}
</syntaxhighlight>

This is one of the functions we set in the config file, and it determines which entities the item can interact with. The <code>asPickedEntity</code> parameter contains the name of the entity the player is looking at at any given time. If the function returns <code>true</code>, the player can use the item on the picked entity. In this example, the function returns <code>true</code> if the picked entity is named <code>ExampleEntity1</code> or <code>ExampleEntity2</code> (ie. the player can use the item on either of these entities).

Finally, let's add one more function.

<syntaxhighlight lang="cpp">
bool OnUse_ItemName(const tString &in asItemType, const tString &in asItemID, const tString &in asTargetEntity, const tString &in asItemEntity, float afTimeElapsed, float afTimeStep)
{
if(asTargetEntity == "ExampleEntity1")
{
// Insert code to interact with ExampleEntity1
}
else if(asTargetEntity == "ExampleEntity2")
{
// Insert code to interact with ExampleEntity2
}

return false;
}
</syntaxhighlight>
This code runs when the player clicks on an entity while holding the item. As shown above, this time the name of the clicked entity is stored in <code>asTargetEntity</code>.

[[Image:CustomItemExample3.jpg|thumb|Picking up the test item|left]]
[[Image:CustomItemExample4.jpg|thumb|Using the test item on a door entity|left]]

File:CustomItemExample4.jpg

2020-11-12T16:14:10Z

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File:CustomItemExample3.jpg

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File:CustomItemExample2.jpg

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File:CustomItemEntityTab.png

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File:Hpl3:CustomItemEntityTab.PNG

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#REDIRECT [[File:CustomItemEntityTab.png]]

HPL3/Amnesia: Rebirth/Tutorials/Inventory items

2020-11-11T17:13:56Z

M654: Simplified some code to make it easier to understand what's going on

This tutorial will explain how to create a custom item that can be picked up, added to the inventory, and used on other entities.

[[Image:Hpl3:CustomItemExample2.jpg|thumb|An example of a custom item in the inventory|right]]

==Tutorial==

===Creating an ItemType===
Let's start by creating an item type. Keep in mind that an ItemType isn't the same as the physical in-game item entity, so a single ItemType can be used with multiple different entities.

Open <code>config/Inventory.cfg</code>. This file contains a list of all ItemTypes in the game. Add a new <code><ItemType></code> tag:
<syntaxhighlight lang="xml">
<ItemType ID="ItemName">
<Inventory Icon="icon_file_name"/>
<Use OnWorld="true" CanUseOnWorldMapCallback="CanUse_ItemName" UseOnWorldMapCallback="OnUse_ItemName"/>
</ItemType>
</syntaxhighlight>

The icons for items shown in the inventory are stored in <code>graphics/inventory/items</code> and saved in the DDS format. Replace <code>icon_file_name</code> with the name of your icon file, and change <code>ItemName</code> to whatever you want to call your item type.

Setting the <code>OnWorld</code> attribute to <code>true</code> will allow this item
type to be used on other entities in-game.

<code>CanUseOnWorldMapCallback</code> and <code>UseOnWorldMapCallback</code> are functions that determine which entities the item type can interact with and what happens when it's used on an entity, respectively. We'll get back to these later.

A detailed list of Use attributes and available functions is located in the beginning of <code>Inventory.cfg</code>, but to keep things simple we'll only be using the three shown above.

===Item name and description===
Now let's give the item a name and a description that will show up when the item is moused over in the inventory. Open <code>config/lang/english.lang</code> and add two entries to the <code>Inventory</code> category: <code>ItemName</code> and <code>ItemName_Desc</code>.

<syntaxhighlight lang="xml">
<LANGUAGE>
<CATEGORY Name="Inventory">
<Entry Name="ItemName">Test Item</Entry>
<Entry Name="ItemName_Desc">This is a simple test item.</Entry>
</CATEGORY>
</LANGUAGE>
</syntaxhighlight>

===Placing the entity===
[[Image:Hpl3:CustomItemEntityTab.PNG|thumb|The Entity tab|right]]
In the level editor, choose an entity to represent the item in-game. Select it, open its '''Entity''' tab and look for a section called '''Pickup'''. If it isn't there, that means that the entity is either a physics object or a static object and you won't be able to pick it up in-game. In that case, open the entity's ENT file, scroll down to the <code><UserDefinedVariables></code> tag and change the <code>EntityType</code> attribute to <code>Prop_Pickup</code>:

<syntaxhighlight lang="xml">
<UserDefinedVariables EntityType="Prop_Pickup">
</syntaxhighlight>

Now re-add the entity to the map. The '''Pickup''' section should now appear. Expand the section and set the ItemType attribute to the ID of the item type you created in <code>Inventory.cfg</code>. Now, when you click on the item in-game it will be added to your inventory.

===Item scripting===
Open the map script and add a new function called <code>CanUse_ItemName</code>:

<syntaxhighlight lang="cpp">
bool CanUse_ItemName(const tString &in asItemType, const tString &in asItemID, const tString &in asPickedEntity)
{
if(asPickedEntity == "ExampleEntity1" || asPickedEntity == "ExampleEntity2")
{
return true;
}
return false;
}
</syntaxhighlight>

This is one of the functions we set in the config file, and it determines which entities the item can interact with. The <code>asPickedEntity</code> parameter contains the name of the entity the player is looking at at any given time. If the function returns <code>true</code>, the player can use the item on the picked entity. In this example, the function returns <code>true</code> if the picked entity is named <code>ExampleEntity1</code> or <code>ExampleEntity2</code> (ie. the player can use the item on either of these entities).

Finally, let's add one more function.

<syntaxhighlight lang="cpp">
bool OnUse_ItemName(const tString &in asItemType, const tString &in asItemID, const tString &in asTargetEntity, const tString &in asItemEntity, float afTimeElapsed, float afTimeStep)
{
if(asTargetEntity == "ExampleEntity1")
{
// Insert code to interact with ExampleEntity1
}
else if(asTargetEntity == "ExampleEntity2")
{
// Insert code to interact with ExampleEntity2
}

return false;
}
</syntaxhighlight>
This code runs when the player clicks on an entity while holding the item. As shown above, this time the name of the clicked entity is stored in <code>asTargetEntity</code>.

[[Image:Hpl3:CustomItemExample3.jpg|thumb|Picking up the test item|left]]
[[Image:Hpl3:CustomItemExample4.jpg|thumb|Using the test item on a door entity|left]]

HPL3/Amnesia: Rebirth/Tutorials/Inventory items

2020-11-11T17:04:56Z

M654: Added pictures

This tutorial will explain how to create a custom item that can be picked up, added to the inventory, and used on other entities.

[[Image:Hpl3:CustomItemExample2.jpg|thumb|An example of a custom item in the inventory|right]]

==Tutorial==

===Creating an ItemType===
Let's start by creating an item type. Keep in mind that an ItemType isn't the same as the physical in-game item entity, so a single ItemType can be used with multiple different entities.

Open <code>config/Inventory.cfg</code>. This file contains a list of all ItemTypes in the game. Add a new <code><ItemType></code> tag:
<syntaxhighlight lang="xml">
<ItemType ID="ItemName">
<Inventory Icon="icon_file_name"/>
<Use OnWorld="true" CanUseOnWorldMapCallback="CanUse_ItemName" UseOnWorldMapCallback="OnUse_ItemName"/>
</ItemType>
</syntaxhighlight>

The icons for items shown in the inventory are stored in <code>graphics/inventory/items</code> and saved in the DDS format. Replace <code>icon_file_name</code> with the name of your icon file, and change <code>ItemName</code> to whatever you want to call your item type.

Setting the <code>OnWorld</code> attribute to <code>true</code> will allow this item
type to be used on other entities in-game.

<code>CanUseOnWorldMapCallback</code> and <code>UseOnWorldMapCallback</code> are functions that determine which entities the item type can interact with and what happens when it's used on an entity, respectively. We'll get back to these later.

A detailed list of Use attributes and available functions is located in the beginning of <code>Inventory.cfg</code>, but to keep things simple we'll only be using the three shown above.

===Item name and description===
Now let's give the item a name and a description that will show up when the item is moused over in the inventory. Open <code>config/lang/english.lang</code> and add two entries to the <code>Inventory</code> category: <code>ItemName</code> and <code>ItemName_Desc</code>.

<syntaxhighlight lang="xml">
<LANGUAGE>
<CATEGORY Name="Inventory">
<Entry Name="ItemName">Test Item</Entry>
<Entry Name="ItemName_Desc">This is a simple test item.</Entry>
</CATEGORY>
</LANGUAGE>
</syntaxhighlight>

===Placing the entity===
[[Image:Hpl3:CustomItemEntityTab.PNG|thumb|The Entity tab|right]]
In the level editor, choose an entity to represent the item in-game. Select it, open its '''Entity''' tab and look for a section called '''Pickup'''. If it isn't there, that means that the entity is either a physics object or a static object and you won't be able to pick it up in-game. In that case, open the entity's ENT file, scroll down to the <code><UserDefinedVariables></code> tag and change the <code>EntityType</code> attribute to <code>Prop_Pickup</code>:

<syntaxhighlight lang="xml">
<UserDefinedVariables EntityType="Prop_Pickup">
</syntaxhighlight>

Now re-add the entity to the map. The '''Pickup''' section should now appear. Expand the section and set the ItemType attribute to the ID of the item type you created in <code>Inventory.cfg</code>. Now, when you click on the item in-game it will be added to your inventory.

===Item scripting===
Open the map script and add a new function called <code>CanUse_ItemName</code>:

<syntaxhighlight lang="cpp">
bool CanUse_ItemName(const tString &in asItemType, const tString &in asItemID, const tString &in asPickedEntity)
{
return asPickedEntity == "ExampleEntity1" || asPickedEntity == "ExampleEntity2";
}
</syntaxhighlight>

This is one of the functions we set in the config file, and it determines which entities the item can interact with. The <code>asPickedEntity</code> parameter contains the name of the entity the player is looking at at any given time. If the function returns <code>true</code>, the player can use the item on the picked entity. In this example, the function returns <code>true</code> if the picked entity is named <code>ExampleEntity1</code> or <code>ExampleEntity2</code> (ie. the player can use the item on either of these entities).

Finally, let's add one more function.

<syntaxhighlight lang="cpp">
bool OnUse_ItemName(const tString &in asItemType, const tString &in asItemID, const tString &in asTargetEntity, const tString &in asItemEntity, float afTimeElapsed, float afTimeStep)
{
if(asTargetEntity == "ExampleEntity1")
{
// Insert code to interact with ExampleEntity1
}
else if(asTargetEntity == "ExampleEntity2")
{
// Insert code to interact with ExampleEntity2
}

return false;
}
</syntaxhighlight>
This code runs when the player clicks on an entity while holding the item. As shown above, this time the name of the clicked entity is stored in <code>asTargetEntity</code>.

[[Image:Hpl3:CustomItemExample3.jpg|thumb|Picking up the test item|left]]
[[Image:Hpl3:CustomItemExample4.jpg|thumb|Using the test item on a door entity|left]]

File:CustomItemExample4.jpg

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File:CustomItemExample3.jpg

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File:CustomItemExample2.jpg

2020-11-11T17:01:28Z

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File:Hpl3:CustomItemExample.PNG

2020-11-11T16:49:25Z

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File:CustomItemEntityTab.png

2020-11-11T16:47:35Z

M654:

HPL3/Amnesia: Rebirth/Tutorials/Inventory items

2020-11-10T22:01:52Z

M654: Created page with "This tutorial will explain how to create a custom item that can be picked up, added to the inventory, and used on other entities. ==Tutorial== {{ConstructionNotice|Function..."

This tutorial will explain how to create a custom item that can be picked up, added to the inventory, and used on other entities.

==Tutorial==

{{ConstructionNotice|Function parameter explanations and example images coming soon|align=left|width=30%}}

===Creating an ItemType===
Let's start by creating an item type. Keep in mind that an ItemType isn't the same as the physical in-game item entity, so a single ItemType can be used with multiple different entities.

Open <code>config/Inventory.cfg</code>. This file contains a list of all ItemTypes in the game. Add a new <code><ItemType></code> tag:
<syntaxhighlight lang="xml">
<ItemType ID="ItemName">
<Inventory Icon="icon_file_name"/>
<Use OnWorld="true" CanUseOnWorldMapCallback="CanUse_ItemName" UseOnWorldMapCallback="OnUse_ItemName"/>
</ItemType>
</syntaxhighlight>

The icons for items shown in the inventory are stored in <code>graphics/inventory/items</code> and saved in the DDS format. Replace <code>icon_file_name</code> with the name of your icon file, and change <code>ItemName</code> to whatever you want to call your item type.

Setting the <code>OnWorld</code> attribute to <code>true</code> will allow this item
type to be used on other entities in-game.

<code>CanUseOnWorldMapCallback</code> and <code>UseOnWorldMapCallback</code> are functions that determine which entities the item type can interact with and what happens when it's used on an entity, respectively. We'll get back to these later.

A detailed list of Use attributes and available functions is located in the beginning of <code>Inventory.cfg</code>, but to keep things simple we'll only be using the three shown above.

===Item name and description===
Now let's give the item a name and a description that will show up when the item is moused over in the inventory. Open <code>config/lang/english.lang</code> and add two entries to the <code>Inventory</code> category: <code>ItemName</code> and <code>ItemName_Desc</code>.

<syntaxhighlight lang="xml">
<LANGUAGE>
<CATEGORY Name="Inventory">
<Entry Name="ItemName">Test Item</Entry>
<Entry Name="ItemName_Desc">This is a simple test item.</Entry>
</CATEGORY>
</LANGUAGE>
</syntaxhighlight>

===Placing the entity===
In the level editor, choose an entity to represent the item in-game. Select it, open its '''Entity''' tab and look for a section called '''Pickup'''. If it isn't there, that means that the entity is either a physics object or a static object and you won't be able to pick it up in-game. In that case, open the entity's ENT file, scroll down to the <code><UserDefinedVariables></code> tag and change the <code>EntityType</code> attribute to <code>Prop_Pickup</code>:

<syntaxhighlight lang="xml">
<UserDefinedVariables EntityType="Prop_Pickup">
</syntaxhighlight>

Now re-add the entity to the map. The '''Pickup''' section should now appear. Expand the section and set the ItemType attribute to the ID of the item type you created in <code>Inventory.cfg</code>. Now, when you click on the item in-game it will be added to your inventory.

===Item scripting===
Open the map script and add a new function called <code>CanUse_ItemName</code>:

<syntaxhighlight lang="cpp">
bool CanUse_ItemName(const tString &in asItemType, const tString &in asItemID, const tString &in asPickedEntity)
{
return asPickedEntity == "ExampleEntity1" || asPickedEntity == "ExampleEntity2";
}
</syntaxhighlight>

This is one of the functions we set in the config file, and it determines which entities the item can interact with. The <code>asPickedEntity</code> parameter contains the name of the entity the player is looking at at any given time. If the function returns <code>true</code>, the player can use the item on the picked entity. In this example, the function returns <code>true</code> if the picked entity is named <code>ExampleEntity1</code> or <code>ExampleEntity2</code> (ie. the player can use the item on either of these entities).

Finally, let's add one more function.

<syntaxhighlight lang="cpp">
bool OnUse_ItemName(const tString &in asItemType, const tString &in asItemID, const tString &in asTargetEntity, const tString &in asItemEntity, float afTimeElapsed, float afTimeStep)
{
if(asTargetEntity == "ExampleEntity1")
{
// Insert code to interact with ExampleEntity1
}
else if(asTargetEntity == "ExampleEntity2")
{
// Insert code to interact with ExampleEntity2
}

return false;
}
</syntaxhighlight>
This code runs when the player clicks on an entity while holding the item. As shown above, this time the name of the clicked entity is stored in <code>asTargetEntity</code>.