<function name="RegisterConstraint" parent="duplicator" type="libraryfunc"> <description>Register a function used for creating a duplicated constraint.</description> <description>Register a function used for creating a duplicator-supported constraint.</description> <realm>Shared</realm> <file line="367-L374">lua/includes/modules/duplicator.lua</file> <args> <arg name="name" type="string">The unique name of new constraint</arg>⤶ <arg name="callback" type="function">Function to be called when this constraint is created</arg>⤶ <arg name="customData" type="vararg">Arguments passed to the callback function</arg>⤶ <arg name="name" type="string">The unique name of the new constraint. It will be used to identify which constraint to apply on duplicator load.</arg>⤶ <arg name="callback" type="function">Function to be called when this constraint is created.⤶ ⤶ It is a good idea to check <page>constraint.CanConstrain</page> before doing anything else.⤶ ⤶ ⤶ You must also call <page>constraint.AddConstraintTable</page> if creating custom constraint entities.⤶ * This is what stores the constraint for duplicator to save and load, as well as for <page>constraint.GetTable</page>.⤶ * The constraint entity must have `Type` key on it. This means that a single entity can only represent one constraint.⤶ ⤶ Optionally, the callback can return up to 4 entities, which are considered the "constraint" entities.⤶ * Each of those is added to `"ropeconstraints"` or `"constraints"` cleanup list based on entity's classname (<page>Player:AddCleanup</page>)⤶ * The first entity is added to the player's entity count (<page>Player:AddCount</page>) in Sandbox.⤶ * None of these entities **should** be the 2 entities being constraint (i.e. a `prop_physics`), but it can be one one of them if you know what you are doing.⤶ </arg>⤶ <arg name="customData" type="vararg">Arguments to be passed to the callback function when the constraint is created via <page>duplicator.CreateConstraintFromTable</page>.⤶ ⤶ The data would be taken the constraint entity table added via <page>constraint.AddConstraintTable</page>. All <page>constraint</page> library constraints call it on the appropriate entity for you. (Typically its the first entity returned by the callback)</arg>⤶ </args> </function> <example> <description>Example of how to define a custom constraint. You apply the constraint via the custom `constraint_MyCustomConstraint` function, and it will automatically support duplicator.</description> <code> function constraint_MyCustomConstraint( Ent1, Ent2, MyCoolData ) if ( !IsValid( Ent1 ) ) then return end if ( !IsValid( Ent2 ) ) then return end -- Your custom constraint code here, you can use "MyCoolData" here, as well as any custom arguments -- Just make sure to save each custom argument in the Ent2 table below, -- and add them to duplicator.RegisterConstraint below as well constraint.AddConstraintTable( Ent1, Ent2, Ent2 ) Ent2:SetTable( { Type = "MyCustomConstraint", Ent1 = Ent1, Ent2 = Ent2, MyCoolData = MyCoolData } ) return Ent2 end duplicator.RegisterConstraint( "MyCustomConstraint", constraint_MyCustomConstraint, "Ent1", "Ent2", "MyCoolData" ) </code> </example>