MultiMesh provides low-level mesh instancing. Drawing thousands of [MeshInstance3D] nodes can be slow, since each object is submitted to the GPU then drawn individually.
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).
[b]Note:[/b] A MultiMesh is a single object, therefore the same maximum lights per object restriction applies. This means, that once the maximum lights are consumed by one or more instances, the rest of the MultiMesh instances will [b]not[/b] receive any lighting.
[b]Note:[/b] Blend Shapes will be ignored if used in a MultiMesh.
<linktitle="Animating thousands of fish with MultiMeshInstance">$DOCS_URL/tutorials/performance/vertex_animation/animating_thousands_of_fish.html</link>
When using [i]physics interpolation[/i], 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.
An alternative to setting the [member buffer] property, which can be used with [i]physics interpolation[/i]. 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 alternative of setting [member buffer] can still be used with interpolation.
[b]Note:[/b] Each component is stored in 32 bits in the Forward+ and Mobile rendering methods, but is packed into 16 bits in the Compatibility rendering method.
For the color to take effect, ensure that [member use_colors] is [code]true[/code] on the [MultiMesh] and [member BaseMaterial3D.vertex_color_use_as_albedo] is [code]true[/code] on the material. If you intend to set an absolute color instead of tinting, make sure the material's albedo color is set to pure white ([code]Color(1, 1, 1)[/code]).
[b]Note:[/b] Each number is stored in 32 bits in the Forward+ and Mobile rendering methods, but is packed into 16 bits in the Compatibility rendering method.
<membername="color_array"type="PackedColorArray"setter="_set_color_array"getter="_get_color_array"deprecated="Accessing this property is very slow. Use [method set_instance_color] and [method get_instance_color] instead.">
Array containing each [Color] used by all instances of this mesh.
<membername="custom_data_array"type="PackedColorArray"setter="_set_custom_data_array"getter="_get_custom_data_array"deprecated="Accessing this property is very slow. Use [method set_instance_custom_data] and [method get_instance_custom_data] instead.">
Array containing each custom data value used by all instances of this mesh, as a [PackedColorArray].
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.
[b]Note:[/b] Fast quality does not equate to low quality. Except in the special cases mentioned above, the quality should be comparable to high quality.
<membername="transform_2d_array"type="PackedVector2Array"setter="_set_transform_2d_array"getter="_get_transform_2d_array"deprecated="Accessing this property is very slow. Use [method set_instance_transform_2d] and [method get_instance_transform_2d] instead.">
Array containing each [Transform2D] value used by all instances of this mesh, as a [PackedVector2Array]. Each transform is divided into 3 [Vector2] values corresponding to the transforms' [code]x[/code], [code]y[/code], and [code]origin[/code].
<membername="transform_array"type="PackedVector3Array"setter="_set_transform_array"getter="_get_transform_array"deprecated="Accessing this property is very slow. Use [method set_instance_transform] and [method get_instance_transform] instead.">
Array containing each [Transform3D] value used by all instances of this mesh, as a [PackedVector3Array]. Each transform is divided into 4 [Vector3] values corresponding to the transforms' [code]x[/code], [code]y[/code], [code]z[/code], and [code]origin[/code].
If [code]true[/code], the [MultiMesh] will use color data (see [method set_instance_color]). Can only be set when [member instance_count] is [code]0[/code] or less. This means that you need to call this method before setting the instance count, or temporarily reset it to [code]0[/code].
If [code]true[/code], the [MultiMesh] will use custom data (see [method set_instance_custom_data]). Can only be set when [member instance_count] is [code]0[/code] or less. This means that you need to call this method before setting the instance count, or temporarily reset it to [code]0[/code].
