# XRMarkerDatabase

A marker database is a collection of [XRMarkerDatabaseEntry](https://developer.android.com/develop/xr/unity/reference/struct/Google/XR/Extensions/XRMarkerDatabaseEntry#structGoogle_1_1XR_1_1Extensions_1_1XRMarkerDatabaseEntry) which stores marker information used to configure marker tracking at runtime when [XRMarkerTrackingFeature](https://developer.android.com/develop/xr/unity/reference/class/Google/XR/Extensions/XRMarkerTrackingFeature#classGoogle_1_1XR_1_1Extensions_1_1XRMarkerTrackingFeature) is enabled.

Marker Databases are immutable at runtime. Create and manipulate an database via Editor, then update XRReferenceImageLibrary and assign to ARTrackedImageManager.referenceLibrary for runtime configuration.

## Summary

### Inheritance

Inherits from: `ScriptableObject`, `IEnumerable< XRMarkerDatabaseEntry >`

| ### Public attributes ||
|---|---|
| [Count](https://developer.android.com/develop/xr/unity/reference/class/Google/XR/Extensions/XRMarkerDatabase#count)` => _entries.Count` | `int` Gets the count of entries. |

| ### Properties ||
|---|---|
| [this[int index]](https://developer.android.com/develop/xr/unity/reference/class/Google/XR/Extensions/XRMarkerDatabase#this[int-index]) | [XRMarkerDatabaseEntry](https://developer.android.com/develop/xr/unity/reference/struct/Google/XR/Extensions/XRMarkerDatabaseEntry#structGoogle_1_1XR_1_1Extensions_1_1XRMarkerDatabaseEntry) Gets an [XRMarkerDatabaseEntry](https://developer.android.com/develop/xr/unity/reference/struct/Google/XR/Extensions/XRMarkerDatabaseEntry#structGoogle_1_1XR_1_1Extensions_1_1XRMarkerDatabaseEntry) from the database. |

| ### Public functions ||
|---|---|
| [GetEnumerator](https://developer.android.com/develop/xr/unity/reference/class/Google/XR/Extensions/XRMarkerDatabase#getenumerator)`()` | `IEnumerator< `[XRMarkerDatabaseEntry](https://developer.android.com/develop/xr/unity/reference/struct/Google/XR/Extensions/XRMarkerDatabaseEntry#structGoogle_1_1XR_1_1Extensions_1_1XRMarkerDatabaseEntry)` >` |

## Public attributes

### Count

```c#
int Count => _entries.Count
```  
Gets the count of entries.

## Properties

### this\[int index\]

```c#
XRMarkerDatabaseEntry this[int index]
```  
Gets an [XRMarkerDatabaseEntry](https://developer.android.com/develop/xr/unity/reference/struct/Google/XR/Extensions/XRMarkerDatabaseEntry#structGoogle_1_1XR_1_1Extensions_1_1XRMarkerDatabaseEntry) from the database.


| Details ||
|---|---|
| Parameters | |---|---| | `index` | The index of the entry . Must be between 0 and [Count](https://developer.android.com/develop/xr/unity/reference/class/Google/XR/Extensions/XRMarkerDatabase#count) - 1. | |
| **Returns** | The [XRMarkerDatabaseEntry](https://developer.android.com/develop/xr/unity/reference/struct/Google/XR/Extensions/XRMarkerDatabaseEntry#structGoogle_1_1XR_1_1Extensions_1_1XRMarkerDatabaseEntry) at *index* . |

## Public functions

### GetEnumerator

```c#
IEnumerator< XRMarkerDatabaseEntry > GetEnumerator()
```