MultiMesh

Inherits: Resource < Reference < Object Provides high-performance mesh instancing.

Description

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.

Tutorials

  • Animating thousands of fish with MultiMeshInstance
  • Optimization using MultiMeshes

    Properties

    Methods

    Enumerations

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

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.

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.

PhysicsInterpolationQuality:

  • INTERP_QUALITY_FAST = 0 —- Always interpolate using Basis lerping, which can produce warping artifacts in some situations.
  • INTERP_QUALITY_HIGH = 1 —- Attempt to interpolate using Basis slerping (spherical linear interpolation) where possible, otherwise fall back to lerping.

    Property Descriptions

  • ColorFormat color_format Format of colors in color array that gets passed to shader.
  • CustomDataFormat custom_data_format Format of custom data in custom data array that gets passed to shader.
  • int instance_count visible_instance_count.
  • Mesh mesh Mesh to be drawn.
  • PhysicsInterpolationQuality 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.
  • TransformFormat transform_format Format of transform used to transform mesh, either 2D or 3D.
  • int 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 VisualInstance.get_transformed_aabb.
  • 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.
  • Transform get_instance_transform ( int instance ) const Transform of a specific instance.
  • Transform2D get_instance_transform_2d ( int instance ) const Transform2D of a specific instance.
  • reset_instance_physics_interpolation ( int instance ) 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.
  • set_as_bulk_array ( 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… 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.
  • set_as_bulk_array_interpolated ( PoolRealArray array_current, PoolRealArray array_previous ) 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. set_as_bulk_array can still be used with interpolation.
  • set_instance_color ( int instance, Color color ) multiplying the mesh’s existing vertex colors. color_format is non-null on the MultiMesh and SpatialMaterial.vertex_color_use_as_albedo is true on the material.
  • set_instance_custom_data ( int instance, Color custom_data ) 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.
  • set_instance_transform ( int instance, Transform transform ) Transform for a specific instance.
  • set_instance_transform_2d ( int instance, Transform2D transform ) Transform2D for a specific instance.