MultiMesh

Inherits: Resource < Reference < Object

Provides high-performance mesh instancing.

Description

MultiMesh provides low-level mesh instancing. Drawing thousands of 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 of each other, performance may be reduced as every single instance will always rendered (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.

Methods

AABB get_aabb ( ) const
Color get_instance_color ( int instance ) const
Color get_instance_custom_data ( int instance ) const
Transform get_instance_transform ( int instance ) const
Transform2D get_instance_transform_2d ( int instance ) const
void set_as_bulk_array ( PoolRealArray array )
void set_instance_color ( int instance, Color color )
void set_instance_custom_data ( int instance, Color custom_data )
void set_instance_transform ( int instance, Transform transform )
void set_instance_transform_2d ( int instance, Transform2D transform )

Enumerations

enum TransformFormat:

  • TRANSFORM_2D = 0 — Use this when using 2D transforms.
  • TRANSFORM_3D = 1 — Use this when using 3D transforms.

enum ColorFormat:

  • COLOR_NONE = 0 — Use when you are not using per-instance Colors.
  • COLOR_8BIT = 1 — Compress Color data into 8 bits when passing to shader. This uses less memory and can be faster, but the Color loses precision.
  • COLOR_FLOAT = 2 — The Color passed into set_instance_color will use 4 floats. Use this for highest precision Color.

enum CustomDataFormat:

  • CUSTOM_DATA_NONE = 0 — Use when you are not using per-instance custom data.
  • 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.
  • CUSTOM_DATA_FLOAT = 2 — The Color passed into set_instance_custom_data will use 4 floats. Use this for highest precision.

Property Descriptions

Default 0
Setter set_color_format(value)
Getter get_color_format()

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

Default 0
Setter set_custom_data_format(value)
Getter get_custom_data_format()

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

  • int instance_count
Default 0
Setter set_instance_count(value)
Getter 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 visible_instance_count.

Setter set_mesh(value)
Getter get_mesh()

Mesh to be drawn.

Default 0
Setter set_transform_format(value)
Getter get_transform_format()

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

  • int visible_instance_count
Default -1
Setter set_visible_instance_count(value)
Getter get_visible_instance_count()

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

Method Descriptions

  • AABB get_aabb ( ) const

Returns the visibility axis-aligned bounding box.

  • Color get_instance_color ( int instance ) const

Gets a specific instance’s color.

  • Color get_instance_custom_data ( int instance ) const

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

Returns the Transform of a specific instance.

Returns the Transform2D of a specific instance.

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…

Transform is stored as 12 floats, 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.

  • void set_instance_color ( int instance, Color color )

Sets the color of a specific instance.

For the color to take effect, ensure that color_format is non-null on the MultiMesh and SpatialMaterial.vertex_color_use_as_albedo is true on the material.

  • void set_instance_custom_data ( int instance, Color custom_data )

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

  • void set_instance_transform ( int instance, Transform transform )

Sets the Transform for a specific instance.

  • void set_instance_transform_2d ( int instance, Transform2D transform )

Sets the Transform2D for a specific instance.