<cat>Dev.Model</cat><title>Custom ModelDoc nodes</title> <cat>Model.Nodes</cat><title>Custom ModelDoc nodes</title> You can make a custom ModelDoc node. This is useful for any gamemode-specific data you want to attach to specific models. These nodes are defined in C# code, and the FGD for these is automatically generated for you. # Generic Game Data 1. Define a struct or class. Add the `ModelDoc.GameData` attribute. ``` /// <summary> /// Spawn a particle when the model is used on an entity. Support for this depends on the entity. /// </summary> [ModelDoc.GameData( "particle", AllowMultiple = true )] public class ModelParticle { [DisplayName( "Particle" ), ResourceType( "vpcf") ] public string Name { get; set; } [JsonPropertyName( "attachment_point" ), FGDType( "model_attachment" )] public string AttachmentPoint { get; set; } [JsonPropertyName( "attachment_type" )] public ParticleAttachment AttachmentType { get; set; } = ParticleAttachment.AttachmentFollow; [JsonPropertyName( "attachment_offset" )] public Vector3 AttachmentOffset { get; set; } } ``` 2. Run your gamemode. The FGD for this node then gets auto-generated. 3. Assign the node in ModelDoc. If you don't know how to do that, you should probably read a ModelDoc guide like [this one](https://wiki.facepunch.com/sbox/Importing_a_new_model#thingsyouregoingtoneed). 4. Now you can use this data in code like so. ``` ModelParticle[] modelParticles = Model.GetData<ModelParticle[]>(); ``` 4a. or like so, which automatically checks of the data exists: ``` if ( Model.TryGetData( out ModelParticle[] modelParticles ) { // Data exists on this model, use it.. } ``` # Break Commands Break commands are a more specific alternative to GenericGameData which allows code to be ran when an entity with a model that has given node breaks via the <page>Breakables</page> class, such as doors, physics props and others. They work identically to GenericGameData but the class markup looks a little different: ``` /// <summary> /// Spawn a particle system when this model breaks. /// </summary> [Library( "break_create_particle" )] public class ModelBreakParticle : IModelBreakCommand { /// <summary> /// The particle to spawn when the model breaks. /// </summary> [JsonPropertyName( "name" ), ResourceType( "vpcf" )] public string Particle { get; set; } // ... public void OnBreak( Sandbox.Breakables.Result res ) { if ( !(res.Source is ModelEntity ent) ) return; var part = Particles.Create( Particle, ent.Position ); // ... } } ``` The `OnBreak` callback will be called automatically when an entity breaks and has a model with (in this case) `break_create_particle` break command. # Other things you can do with this There are multiple attributes that you can use in order to make your own custom designers/helpers: - `ModelDoc.Axis` - `ModelDoc.Box` - `ModelDoc.Sphere` - `ModelDoc.Capsule` - `ModelDoc.Cylinder` - `ModelDoc.Line` - `ModelDoc.HandPose` - `ModelDoc.EditorWidget`