API Reference

Everything you can do with MeshVaultAPI. Add using MeshVault; to your mod.

Table of contents

• Spawning Meshes
  • Spawn
    • How material/color overrides work
  • SpawnDecal
• Looking Up Meshes
  • HasMesh
  • GetMesh
  • ListMeshes
• Registering Your Own Meshes
  • RegisterMeshes
  • IsPrefixRegistered
• Registering Decals
  • RegisterDecals (from byte data)
  • RegisterDecals (from assembly resources)
  • ListRegisteredDecals / GetRegisteredDecal / IsDecalPrefixRegistered
• Advanced
  • GetAllEntries
  • BuildMaterialCatalog
  • FindSceneMaterial / FindSceneTexture
  • Init

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Spawning Meshes

Spawn

public static GameObject Spawn(
    string id,
    Vector3 position,
    Quaternion rotation,
    Transform parent = null,
    string namePrefix = "MeshVault",
    string[] materialOverrides = null,
    Color?[] colorOverrides = null
)

Creates a GameObject from a mesh database entry. The object comes with a MeshFilter, MeshRenderer, MeshCollider, and any child meshes already attached.

Returns null if the mesh ID doesn’t exist. Always check with HasMesh() first if you’re not sure.

Parameters:

Parameter	Type	Default	What it does
id	string		The mesh ID (e.g. "dumpster", "sofa_double")
position	Vector3		Where to place it in the world
rotation	Quaternion		Which way it faces
parent	Transform	null	Attach to a parent object (e.g. a building)
namePrefix	string	"MeshVault"	Prefix for the GameObject’s name in the hierarchy
materialOverrides	string[]	null	Swap out materials by slot (see below)
colorOverrides	Color?[]	null	Tint materials by slot (see below)

How material/color overrides work

Both arrays use the same slot ordering: submeshes first, then child meshes. For a mesh with 2 submeshes and 1 child mesh, slot 0 is submesh 0, slot 1 is submesh 1, slot 2 is the child mesh. Use null in any slot to keep the default.

// Mesh has 2 submeshes. Override slot 1 material, tint slot 0 red.
var go = MeshVaultAPI.Spawn("sofa_double", pos, rot,
    materialOverrides: new[] { null, "leather_black" },
    colorOverrides: new Color?[] { new Color(1f, 0f, 0f), null });

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SpawnDecal

public static GameObject SpawnDecal(
    string textureName,
    Vector3 position,
    Quaternion rotation,
    Color? tintColor = null,
    Vector3? scale = null,
    Transform parent = null
)

Projects a texture onto nearby surfaces using a DecalProjector. The projector’s forward direction (+Z) should point into the surface.

Looks up the texture in the decal registry first (see RegisterDecals), then searches game assets as a fallback. Returns null if the texture or decal shader can’t be found.

var decal = MeshVaultAPI.SpawnDecal("Graffiti_01",
    wallPosition,
    Quaternion.LookRotation(wallNormal),
    tintColor: Color.red,
    scale: new Vector3(2f, 2f, 1f));

Parameter	Type	Default	What it does
textureName	string		Texture name or registered decal ID
position	Vector3		Where to place the projector
rotation	Quaternion		Direction the projector faces (forward = into the surface)
tintColor	Color?	white	Color multiplied onto the texture
scale	Vector3?	(1,1,1)	Width and height of the projection (Z is ignored)
parent	Transform	null	Parent object to attach to

---

Looking Up Meshes

HasMesh

public static bool HasMesh(string id)

Returns true if the ID exists in the database. Use this before Spawn() if you’re not sure the mesh is available.

GetMesh

public static MeshEntry GetMesh(string id)

Returns the raw MeshEntry data for an ID, or null if not found. You can inspect bounds, material names, child meshes, etc. before spawning.

ListMeshes

public static string[] ListMeshes()

Returns every mesh ID in the database, including entries registered by other mods.

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Registering Your Own Meshes

If the built-in database doesn’t have what you need, you can ship your own mesh data as JSON and register it at runtime. See JSON Schema for the JSON format.

RegisterMeshes

public static int RegisterMeshes(
    string prefix,
    string modName,
    string json
)

Parses your JSON and adds the entries to the shared database. Once registered, any mod can spawn them with Spawn().

Returns the number of entries registered, or -1 if something went wrong (check the MelonLoader log for details).

Prefix rules:

• Pick a short prefix for your mod (e.g. "otc", "mymod"). Lowercase letters and numbers only, no underscores.
• Every mesh ID in your JSON must start with prefix_ (e.g. "otc_custom_desk")
• First mod to claim a prefix owns it for the session. No other mod can use it.

// Load your mesh JSON (embedded resource, file, string literal, etc.)
string json = LoadMyMeshJson();

int count = MeshVaultAPI.RegisterMeshes("mymod", "My Mod Name", json);
if (count > 0)
{
    // Your meshes are now available to everyone
    var go = MeshVaultAPI.Spawn("mymod_custom_desk", position, rotation);
}

IsPrefixRegistered

public static bool IsPrefixRegistered(string prefix)

Check if a prefix is already claimed before trying to register.

---

Registering Decals

Custom textures for use with SpawnDecal(). Same prefix system as meshes.

RegisterDecals (from byte data)

public static int RegisterDecals(
    string prefix,
    string modName,
    Dictionary<string, byte[]> textures
)

Pass a dictionary of texture names to raw PNG/JPG bytes. Keys that don’t already start with prefix_ are auto-prefixed (e.g. key "logo" with prefix "mymod" becomes "mymod_logo").

RegisterDecals (from assembly resources)

public static int RegisterDecals(
    string prefix,
    string modName,
    Assembly assembly,
    string resourcePrefix = null
)

Automatically finds and registers all embedded PNG/JPG resources in your assembly. Texture names are extracted from the resource path (e.g. MyMod.Decals.logo.png becomes "logo", stored as "mymod_logo").

// Register all PNGs in MyMod.Decals namespace
int count = MeshVaultAPI.RegisterDecals("mymod", "My Mod",
    Assembly.GetExecutingAssembly(), "MyMod.Decals.");

ListRegisteredDecals / GetRegisteredDecal / IsDecalPrefixRegistered

public static string[] ListRegisteredDecals()
public static Texture2D GetRegisteredDecal(string id)
public static bool IsDecalPrefixRegistered(string prefix)

Query the decal registry. Same pattern as the mesh query methods.

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Advanced

These methods exist for specific use cases. Most mods won’t need them.

GetAllEntries

public static Dictionary<string, MeshEntry> GetAllEntries()

Returns the full internal dictionary. Useful if you need to iterate over all entries or build tooling.

BuildMaterialCatalog

public static Dictionary<string, float[]> BuildMaterialCatalog()

Scans the database and returns a map of every unique material name to its RGBA color. Used internally by MeshPlacer’s material picker UI.

FindSceneMaterial / FindSceneTexture

public static Material FindSceneMaterial(string matName)
public static Texture FindSceneTexture(string texName)

Look up a material or texture by name from the loaded game scene. Results are cached. You’d use these if you’re building something custom outside of Spawn().

Init

public static void Init()

Forces the database to load. You don’t need to call this. All query and spawn methods trigger loading automatically on first use.