luma.gl/docs/api-reference/core/buffer-layout.md

BufferLayout

The bufferLayout type provides information about how the buffers the application is planning to bind map to the attributes. The BufferLayout stores the dynamic structure of a render pipeline binding points.

BufferLayout affects buffers bound with RenderPipeline.setAttributes() or Model.setAttributes(). The names of buffer bindings are determined by the buffer mapping. Buffer names will match the attribute names, however for interleaved buffers the buffer layout defines new buffer names, that then becomes valid in RenderPipeline.setAttributes() and Model.setAttributes().

Usage

The simplest use case is to provide a non-default vertex type:

  bufferLayout: {
    attributes: [
      {name: 'instancePositions', format: 'float32x3'}
      ...
      // RGBA colors can be efficiently encoded in 4 8bit bytes, instead of 4 32bit floats
      {name: 'instanceColors': format: 'uint8normx4'},
    ]
  ],

  bufferLayout: {
    attributes: [
      {name: 'instancePositions', format: 'float32x3'}
      ...
      // RGBA colors can be efficiently encoded in 4 8bit bytes, instead of 4 32bit floats
      {name: 'instanceColors': format: 'uint8normx4'},
    ],
  }

A more advanced use case is interleaving: two attributes access the same buffer in an interleaved way. Note that this introduces a new buffer name that can be referenced in setAttributes()

  bufferLayout: [
    {name: 'particles', attributes: [
      // Note that strides are automatically calculated assuming a packed buffer.
      {name: 'instancePositions'},
      {name: 'instanceVelocities'}
    ]
  ],

In the above case case a new buffer name particles is defined and setAttributes() calls will recognize that name and bind the provided buffer to all the interleaved attributes.

Fields

Each row in the buffer mapping describes one buffer.

• name: string the name of the attribute and the buffer

• format: VertexFormat the format of the buffer's memory.

• byteOffset?: number the offset into the buffer (defaults to 0)

• byteStride?: number the stride between elements in the buffer (default assumes a packed buffer)

• attributes: InterleavedAttribute[]

Interleaved Attribute Description

• name: string the name of the attribute and the buffer
• format: VertexFormat the format of the buffer's memory.

:::info Interleaving attributes into the same buffer does not increase the number of attributes that can be used in a shader (16 on many systems). :::