godot-docs/classes/class_multimesh.rst

:github_url: hide

.. DO NOT EDIT THIS FILE!!!
.. Generated automatically from Godot engine sources.
.. Generator: https://github.com/godotengine/godot/tree/3.6/doc/tools/make_rst.py.
.. XML source: https://github.com/godotengine/godot/tree/3.6/doc/classes/MultiMesh.xml.

.. _class_MultiMesh:

MultiMesh
=========

**Inherits:** :ref:`Resource<class_Resource>` **<** :ref:`Reference<class_Reference>` **<** :ref:`Object<class_Object>`

Provides high-performance mesh instancing.

.. rst-class:: classref-introduction-group

Description
-----------

MultiMesh provides low-level mesh instancing. Drawing thousands of :ref:`MeshInstance<class_MeshInstance>` nodes can be slow, since each object is submitted to the GPU then drawn individually.

MultiMesh is much faster as it can draw thousands of instances with a single draw call, resulting in less API overhead.

As a drawback, if the instances are too far away from each other, performance may be reduced as every single instance will always render (they are spatially indexed as one, for the whole object).

Since instances may have any behavior, the AABB used for visibility must be provided by the user.

.. rst-class:: classref-introduction-group

Tutorials
---------

- :doc:`../tutorials/performance/vertex_animation/animating_thousands_of_fish`

- :doc:`../tutorials/performance/using_multimesh`

.. rst-class:: classref-reftable-group

Properties
----------

.. table::
   :widths: auto

   +--------------------------------------------------------------------------------+----------------------------------------------------------------------------------------------+--------+
   | :ref:`ColorFormat<enum_MultiMesh_ColorFormat>`                                 | :ref:`color_format<class_MultiMesh_property_color_format>`                                   | ``0``  |
   +--------------------------------------------------------------------------------+----------------------------------------------------------------------------------------------+--------+
   | :ref:`CustomDataFormat<enum_MultiMesh_CustomDataFormat>`                       | :ref:`custom_data_format<class_MultiMesh_property_custom_data_format>`                       | ``0``  |
   +--------------------------------------------------------------------------------+----------------------------------------------------------------------------------------------+--------+
   | :ref:`int<class_int>`                                                          | :ref:`instance_count<class_MultiMesh_property_instance_count>`                               | ``0``  |
   +--------------------------------------------------------------------------------+----------------------------------------------------------------------------------------------+--------+
   | :ref:`Mesh<class_Mesh>`                                                        | :ref:`mesh<class_MultiMesh_property_mesh>`                                                   |        |
   +--------------------------------------------------------------------------------+----------------------------------------------------------------------------------------------+--------+
   | :ref:`PhysicsInterpolationQuality<enum_MultiMesh_PhysicsInterpolationQuality>` | :ref:`physics_interpolation_quality<class_MultiMesh_property_physics_interpolation_quality>` | ``0``  |
   +--------------------------------------------------------------------------------+----------------------------------------------------------------------------------------------+--------+
   | :ref:`TransformFormat<enum_MultiMesh_TransformFormat>`                         | :ref:`transform_format<class_MultiMesh_property_transform_format>`                           | ``0``  |
   +--------------------------------------------------------------------------------+----------------------------------------------------------------------------------------------+--------+
   | :ref:`int<class_int>`                                                          | :ref:`visible_instance_count<class_MultiMesh_property_visible_instance_count>`               | ``-1`` |
   +--------------------------------------------------------------------------------+----------------------------------------------------------------------------------------------+--------+

.. rst-class:: classref-reftable-group

Methods
-------

.. table::
   :widths: auto

   +---------------------------------------+----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
   | :ref:`AABB<class_AABB>`               | :ref:`get_aabb<class_MultiMesh_method_get_aabb>` **(** **)** |const|                                                                                                                                                       |
   +---------------------------------------+----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
   | :ref:`Color<class_Color>`             | :ref:`get_instance_color<class_MultiMesh_method_get_instance_color>` **(** :ref:`int<class_int>` instance **)** |const|                                                                                                    |
   +---------------------------------------+----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
   | :ref:`Color<class_Color>`             | :ref:`get_instance_custom_data<class_MultiMesh_method_get_instance_custom_data>` **(** :ref:`int<class_int>` instance **)** |const|                                                                                        |
   +---------------------------------------+----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
   | :ref:`Transform<class_Transform>`     | :ref:`get_instance_transform<class_MultiMesh_method_get_instance_transform>` **(** :ref:`int<class_int>` instance **)** |const|                                                                                            |
   +---------------------------------------+----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
   | :ref:`Transform2D<class_Transform2D>` | :ref:`get_instance_transform_2d<class_MultiMesh_method_get_instance_transform_2d>` **(** :ref:`int<class_int>` instance **)** |const|                                                                                      |
   +---------------------------------------+----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
   | void                                  | :ref:`reset_instance_physics_interpolation<class_MultiMesh_method_reset_instance_physics_interpolation>` **(** :ref:`int<class_int>` instance **)**                                                                        |
   +---------------------------------------+----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
   | void                                  | :ref:`set_as_bulk_array<class_MultiMesh_method_set_as_bulk_array>` **(** :ref:`PoolRealArray<class_PoolRealArray>` array **)**                                                                                             |
   +---------------------------------------+----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
   | void                                  | :ref:`set_as_bulk_array_interpolated<class_MultiMesh_method_set_as_bulk_array_interpolated>` **(** :ref:`PoolRealArray<class_PoolRealArray>` array_current, :ref:`PoolRealArray<class_PoolRealArray>` array_previous **)** |
   +---------------------------------------+----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
   | void                                  | :ref:`set_instance_color<class_MultiMesh_method_set_instance_color>` **(** :ref:`int<class_int>` instance, :ref:`Color<class_Color>` color **)**                                                                           |
   +---------------------------------------+----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
   | void                                  | :ref:`set_instance_custom_data<class_MultiMesh_method_set_instance_custom_data>` **(** :ref:`int<class_int>` instance, :ref:`Color<class_Color>` custom_data **)**                                                         |
   +---------------------------------------+----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
   | void                                  | :ref:`set_instance_transform<class_MultiMesh_method_set_instance_transform>` **(** :ref:`int<class_int>` instance, :ref:`Transform<class_Transform>` transform **)**                                                       |
   +---------------------------------------+----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
   | void                                  | :ref:`set_instance_transform_2d<class_MultiMesh_method_set_instance_transform_2d>` **(** :ref:`int<class_int>` instance, :ref:`Transform2D<class_Transform2D>` transform **)**                                             |
   +---------------------------------------+----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+

.. rst-class:: classref-section-separator

----

.. rst-class:: classref-descriptions-group

Enumerations
------------

.. _enum_MultiMesh_TransformFormat:

.. rst-class:: classref-enumeration

enum **TransformFormat**:

.. _class_MultiMesh_constant_TRANSFORM_2D:

.. rst-class:: classref-enumeration-constant

:ref:`TransformFormat<enum_MultiMesh_TransformFormat>` **TRANSFORM_2D** = ``0``

Use this when using 2D transforms.

.. _class_MultiMesh_constant_TRANSFORM_3D:

.. rst-class:: classref-enumeration-constant

:ref:`TransformFormat<enum_MultiMesh_TransformFormat>` **TRANSFORM_3D** = ``1``

Use this when using 3D transforms.

.. rst-class:: classref-item-separator

----

.. _enum_MultiMesh_ColorFormat:

.. rst-class:: classref-enumeration

enum **ColorFormat**:

.. _class_MultiMesh_constant_COLOR_NONE:

.. rst-class:: classref-enumeration-constant

:ref:`ColorFormat<enum_MultiMesh_ColorFormat>` **COLOR_NONE** = ``0``

Use when you are not using per-instance :ref:`Color<class_Color>`\ s.

.. _class_MultiMesh_constant_COLOR_8BIT:

.. rst-class:: classref-enumeration-constant

:ref:`ColorFormat<enum_MultiMesh_ColorFormat>` **COLOR_8BIT** = ``1``

Compress :ref:`Color<class_Color>` data into 8 bits when passing to shader. This uses less memory and can be faster, but the :ref:`Color<class_Color>` loses precision.

.. _class_MultiMesh_constant_COLOR_FLOAT:

.. rst-class:: classref-enumeration-constant

:ref:`ColorFormat<enum_MultiMesh_ColorFormat>` **COLOR_FLOAT** = ``2``

The :ref:`Color<class_Color>` passed into :ref:`set_instance_color<class_MultiMesh_method_set_instance_color>` will use 4 floats. Use this for highest precision :ref:`Color<class_Color>`.

.. rst-class:: classref-item-separator

----

.. _enum_MultiMesh_CustomDataFormat:

.. rst-class:: classref-enumeration

enum **CustomDataFormat**:

.. _class_MultiMesh_constant_CUSTOM_DATA_NONE:

.. rst-class:: classref-enumeration-constant

:ref:`CustomDataFormat<enum_MultiMesh_CustomDataFormat>` **CUSTOM_DATA_NONE** = ``0``

Use when you are not using per-instance custom data.

.. _class_MultiMesh_constant_CUSTOM_DATA_8BIT:

.. rst-class:: classref-enumeration-constant

:ref:`CustomDataFormat<enum_MultiMesh_CustomDataFormat>` **CUSTOM_DATA_8BIT** = ``1``

Compress custom_data into 8 bits when passing to shader. This uses less memory and can be faster, but loses precision and range. Floats packed into 8 bits can only represent values between 0 and 1, numbers outside that range will be clamped.

.. _class_MultiMesh_constant_CUSTOM_DATA_FLOAT:

.. rst-class:: classref-enumeration-constant

:ref:`CustomDataFormat<enum_MultiMesh_CustomDataFormat>` **CUSTOM_DATA_FLOAT** = ``2``

The :ref:`Color<class_Color>` passed into :ref:`set_instance_custom_data<class_MultiMesh_method_set_instance_custom_data>` will use 4 floats. Use this for highest precision.

.. rst-class:: classref-item-separator

----

.. _enum_MultiMesh_PhysicsInterpolationQuality:

.. rst-class:: classref-enumeration

enum **PhysicsInterpolationQuality**:

.. _class_MultiMesh_constant_INTERP_QUALITY_FAST:

.. rst-class:: classref-enumeration-constant

:ref:`PhysicsInterpolationQuality<enum_MultiMesh_PhysicsInterpolationQuality>` **INTERP_QUALITY_FAST** = ``0``

Always interpolate using Basis lerping, which can produce warping artifacts in some situations.

.. _class_MultiMesh_constant_INTERP_QUALITY_HIGH:

.. rst-class:: classref-enumeration-constant

:ref:`PhysicsInterpolationQuality<enum_MultiMesh_PhysicsInterpolationQuality>` **INTERP_QUALITY_HIGH** = ``1``

Attempt to interpolate using Basis slerping (spherical linear interpolation) where possible, otherwise fall back to lerping.

.. rst-class:: classref-section-separator

----

.. rst-class:: classref-descriptions-group

Property Descriptions
---------------------

.. _class_MultiMesh_property_color_format:

.. rst-class:: classref-property

:ref:`ColorFormat<enum_MultiMesh_ColorFormat>` **color_format** = ``0``

.. rst-class:: classref-property-setget

- void **set_color_format** **(** :ref:`ColorFormat<enum_MultiMesh_ColorFormat>` value **)**
- :ref:`ColorFormat<enum_MultiMesh_ColorFormat>` **get_color_format** **(** **)**

Format of colors in color array that gets passed to shader.

.. rst-class:: classref-item-separator

----

.. _class_MultiMesh_property_custom_data_format:

.. rst-class:: classref-property

:ref:`CustomDataFormat<enum_MultiMesh_CustomDataFormat>` **custom_data_format** = ``0``

.. rst-class:: classref-property-setget

- void **set_custom_data_format** **(** :ref:`CustomDataFormat<enum_MultiMesh_CustomDataFormat>` value **)**
- :ref:`CustomDataFormat<enum_MultiMesh_CustomDataFormat>` **get_custom_data_format** **(** **)**

Format of custom data in custom data array that gets passed to shader.

.. rst-class:: classref-item-separator

----

.. _class_MultiMesh_property_instance_count:

.. rst-class:: classref-property

:ref:`int<class_int>` **instance_count** = ``0``

.. rst-class:: classref-property-setget

- void **set_instance_count** **(** :ref:`int<class_int>` value **)**
- :ref:`int<class_int>` **get_instance_count** **(** **)**

Number of instances that will get drawn. This clears and (re)sizes the buffers. By default, all instances are drawn but you can limit this with :ref:`visible_instance_count<class_MultiMesh_property_visible_instance_count>`.

.. rst-class:: classref-item-separator

----

.. _class_MultiMesh_property_mesh:

.. rst-class:: classref-property

:ref:`Mesh<class_Mesh>` **mesh**

.. rst-class:: classref-property-setget

- void **set_mesh** **(** :ref:`Mesh<class_Mesh>` value **)**
- :ref:`Mesh<class_Mesh>` **get_mesh** **(** **)**

Mesh to be drawn.

.. rst-class:: classref-item-separator

----

.. _class_MultiMesh_property_physics_interpolation_quality:

.. rst-class:: classref-property

:ref:`PhysicsInterpolationQuality<enum_MultiMesh_PhysicsInterpolationQuality>` **physics_interpolation_quality** = ``0``

.. rst-class:: classref-property-setget

- void **set_physics_interpolation_quality** **(** :ref:`PhysicsInterpolationQuality<enum_MultiMesh_PhysicsInterpolationQuality>` value **)**
- :ref:`PhysicsInterpolationQuality<enum_MultiMesh_PhysicsInterpolationQuality>` **get_physics_interpolation_quality** **(** **)**

Choose whether to use an interpolation method that favors speed or quality.

When using low physics tick rates (typically below 20) or high rates of object rotation, you may get better results from the high quality setting.

\ **Note:** Fast quality does not equate to low quality. Except in the special cases mentioned above, the quality should be comparable to high quality.

.. rst-class:: classref-item-separator

----

.. _class_MultiMesh_property_transform_format:

.. rst-class:: classref-property

:ref:`TransformFormat<enum_MultiMesh_TransformFormat>` **transform_format** = ``0``

.. rst-class:: classref-property-setget

- void **set_transform_format** **(** :ref:`TransformFormat<enum_MultiMesh_TransformFormat>` value **)**
- :ref:`TransformFormat<enum_MultiMesh_TransformFormat>` **get_transform_format** **(** **)**

Format of transform used to transform mesh, either 2D or 3D.

.. rst-class:: classref-item-separator

----

.. _class_MultiMesh_property_visible_instance_count:

.. rst-class:: classref-property

:ref:`int<class_int>` **visible_instance_count** = ``-1``

.. rst-class:: classref-property-setget

- void **set_visible_instance_count** **(** :ref:`int<class_int>` value **)**
- :ref:`int<class_int>` **get_visible_instance_count** **(** **)**

Limits the number of instances drawn, -1 draws all instances. Changing this does not change the sizes of the buffers.

.. rst-class:: classref-section-separator

----

.. rst-class:: classref-descriptions-group

Method Descriptions
-------------------

.. _class_MultiMesh_method_get_aabb:

.. rst-class:: classref-method

:ref:`AABB<class_AABB>` **get_aabb** **(** **)** |const|

Returns the visibility axis-aligned bounding box in local space. See also :ref:`VisualInstance.get_transformed_aabb<class_VisualInstance_method_get_transformed_aabb>`.

.. rst-class:: classref-item-separator

----

.. _class_MultiMesh_method_get_instance_color:

.. rst-class:: classref-method

:ref:`Color<class_Color>` **get_instance_color** **(** :ref:`int<class_int>` instance **)** |const|

Gets a specific instance's color.

.. rst-class:: classref-item-separator

----

.. _class_MultiMesh_method_get_instance_custom_data:

.. rst-class:: classref-method

:ref:`Color<class_Color>` **get_instance_custom_data** **(** :ref:`int<class_int>` instance **)** |const|

Returns the custom data that has been set for a specific instance.

.. rst-class:: classref-item-separator

----

.. _class_MultiMesh_method_get_instance_transform:

.. rst-class:: classref-method

:ref:`Transform<class_Transform>` **get_instance_transform** **(** :ref:`int<class_int>` instance **)** |const|

Returns the :ref:`Transform<class_Transform>` of a specific instance.

.. rst-class:: classref-item-separator

----

.. _class_MultiMesh_method_get_instance_transform_2d:

.. rst-class:: classref-method

:ref:`Transform2D<class_Transform2D>` **get_instance_transform_2d** **(** :ref:`int<class_int>` instance **)** |const|

Returns the :ref:`Transform2D<class_Transform2D>` of a specific instance.

.. rst-class:: classref-item-separator

----

.. _class_MultiMesh_method_reset_instance_physics_interpolation:

.. rst-class:: classref-method

void **reset_instance_physics_interpolation** **(** :ref:`int<class_int>` instance **)**

When using *physics interpolation*, this function allows you to prevent interpolation on an instance in the current physics tick.

This allows you to move instances instantaneously, and should usually be used when initially placing an instance such as a bullet to prevent graphical glitches.

.. rst-class:: classref-item-separator

----

.. _class_MultiMesh_method_set_as_bulk_array:

.. rst-class:: classref-method

void **set_as_bulk_array** **(** :ref:`PoolRealArray<class_PoolRealArray>` array **)**

Sets all data related to the instances in one go. This is especially useful when loading the data from disk or preparing the data from GDNative.

All data is packed in one large float array. An array may look like this: Transform for instance 1, color data for instance 1, custom data for instance 1, transform for instance 2, color data for instance 2, etc...

\ :ref:`Transform<class_Transform>` is stored as 12 floats, :ref:`Transform2D<class_Transform2D>` is stored as 8 floats, ``COLOR_8BIT`` / ``CUSTOM_DATA_8BIT`` is stored as 1 float (4 bytes as is) and ``COLOR_FLOAT`` / ``CUSTOM_DATA_FLOAT`` is stored as 4 floats.

.. rst-class:: classref-item-separator

----

.. _class_MultiMesh_method_set_as_bulk_array_interpolated:

.. rst-class:: classref-method

void **set_as_bulk_array_interpolated** **(** :ref:`PoolRealArray<class_PoolRealArray>` array_current, :ref:`PoolRealArray<class_PoolRealArray>` array_previous **)**

An alternative version of :ref:`set_as_bulk_array<class_MultiMesh_method_set_as_bulk_array>` which can be used with *physics interpolation*. This method takes two arrays, and can set the data for the current and previous tick in one go. The renderer will automatically interpolate the data at each frame.

This is useful for situations where the order of instances may change from physics tick to tick, such as particle systems.

When the order of instances is coherent, the simpler :ref:`set_as_bulk_array<class_MultiMesh_method_set_as_bulk_array>` can still be used with interpolation.

.. rst-class:: classref-item-separator

----

.. _class_MultiMesh_method_set_instance_color:

.. rst-class:: classref-method

void **set_instance_color** **(** :ref:`int<class_int>` instance, :ref:`Color<class_Color>` color **)**

Sets the color of a specific instance by *multiplying* the mesh's existing vertex colors.

For the color to take effect, ensure that :ref:`color_format<class_MultiMesh_property_color_format>` is non-``null`` on the **MultiMesh** and :ref:`Material3D.vertex_color_use_as_albedo<class_Material3D_property_vertex_color_use_as_albedo>` is ``true`` on the material. If the color doesn't look as expected, make sure the material's albedo color is set to pure white (``Color(1, 1, 1)``).

.. rst-class:: classref-item-separator

----

.. _class_MultiMesh_method_set_instance_custom_data:

.. rst-class:: classref-method

void **set_instance_custom_data** **(** :ref:`int<class_int>` instance, :ref:`Color<class_Color>` custom_data **)**

Sets custom data for a specific instance. Although :ref:`Color<class_Color>` is used, it is just a container for 4 floating point numbers. The format of the number can change depending on the :ref:`CustomDataFormat<enum_MultiMesh_CustomDataFormat>` used.

.. rst-class:: classref-item-separator

----

.. _class_MultiMesh_method_set_instance_transform:

.. rst-class:: classref-method

void **set_instance_transform** **(** :ref:`int<class_int>` instance, :ref:`Transform<class_Transform>` transform **)**

Sets the :ref:`Transform<class_Transform>` for a specific instance.

.. rst-class:: classref-item-separator

----

.. _class_MultiMesh_method_set_instance_transform_2d:

.. rst-class:: classref-method

void **set_instance_transform_2d** **(** :ref:`int<class_int>` instance, :ref:`Transform2D<class_Transform2D>` transform **)**

Sets the :ref:`Transform2D<class_Transform2D>` for a specific instance.

.. |virtual| replace:: :abbr:`virtual (This method should typically be overridden by the user to have any effect.)`
.. |const| replace:: :abbr:`const (This method has no side effects. It doesn't modify any of the instance's member variables.)`
.. |vararg| replace:: :abbr:`vararg (This method accepts any number of arguments after the ones described here.)`
.. |static| replace:: :abbr:`static (This method doesn't need an instance to be called, so it can be called directly using the class name.)`