GPUDevice: createBindGroupLayout() method

descriptor

An object containing the following properties:

entries

An array of entry objects, each one of which describes a single shader resource binding to be included in the GPUBindGroupLayout. Each entry will correspond to an entry defined in a GPUBindGroup (created via a GPUDevice.createBindGroup() call) that uses this GPUBindGroupLayout object as a template.

label Optional

A string providing a label that can be used to identify the object, for example in GPUError messages or console warnings.

An entry object includes the following properties:

binding

A number representing a unique identifier for this particular entry, which matches the binding value of a corresponding GPUBindGroup entry. In addition, it corresponds to a @binding attribute in the shader code contained in the GPUShaderModule used in a related pipeline.

visibility

One or more bitwise flags defining the shader stages that a GPUBindGroup entry corresponding to this entry will be visible to. Possible values are:

• GPUShaderStage.COMPUTE: The bind group entry will be accessible to compute shaders.
• GPUShaderStage.FRAGMENT: The bind group entry will be accessible to fragment shaders.
• GPUShaderStage.VERTEX: The bind group entry will be accessible to vertex shaders.

Note that multiple stages can be specified by separating values with pipe symbols, for example:

visibility: GPUShaderStage.FRAGMENT | GPUShaderStage.VERTEX;

"Resource layout object"

An object that defines the required binding resource type and structure of the GPUBindGroup entry corresponding to this entry. This property can be one of buffer, externalTexture, sampler, storageTexture, or texture, the object structures of which are described in the next section.

The resource layout object can be one of the following (see also GPUDevice.createBindGroup() for details of how the required resources for each entry are structured):

• buffer: Indicates that the corresponding GPUBindGroup entry will be a GPUBufferBinding object, which contains a GPUBuffer plus offset and size values. A buffer resource layout object can contain the following properties:

  hasDynamicOffset Optional

  A boolean. If set to true, it indicates that this binding requires a dynamic offset, for example as set during a GPURenderPassEncoder.setBindGroup() call. If omitted, hasDynamicOffset defaults to false.

  minBindingSize Optional

  A number indicating the minimum allowed size, in bytes, of bound buffers. If omitted, minBindingSize defaults to 0. If the value is 0, minimum buffer size is ignored during pipeline creation and is instead validated by issued draw/dispatch commands.

  type Optional

  An enumerated value specifying the required type for GPUBuffers bound to this binding (see GPUDevice.createBuffer() for more information on buffer types). Possible values are:

  • "read-only-storage": A read-only buffer created with a usage of GPUBufferUsage.STORAGE.
  • "storage": A writable buffer created with a usage of GPUBufferUsage.STORAGE.
  • "uniform": A buffer created with a usage of GPUBufferUsage.UNIFORM.

  If omitted, type defaults to "uniform".

• externalTexture: Indicates that the corresponding GPUBindGroup entry will be a GPUExternalTexture object. An externalTexture resource layout object is empty — {}.
• sampler: Indicates that the corresponding GPUBindGroup entry will be a GPUSampler object. A sampler resource layout object can contain the following properties:

  type Optional

  An enumerated value specifying the required type for GPUSamplers bound to this binding (see GPUDevice.createSampler() for more information on sampler types). Possible values are:

  • "comparison": A comparison sampler.
  • "filtering": A filtering sampler.
  • "non-filtering": A non-filtering sampler.

  If omitted, type defaults to "filtering".

• storageTexture: Indicates that the corresponding GPUBindGroup entry will be a GPUTextureView object. A storageTexture resource layout object can contain the following properties:

  access Optional

  An enumerated value specifying whether texture views bound to this binding will be bound for read and/or write access. Possible values are currently "write-only" and undefined, with the intention to add more access modes in the future. If omitted, the default value is "write-only".

  format

  An enumerated value specifying the required format of texture views bound to this binding. See the specification's Texture Formats section for all the available format values.

  viewDimension Optional

  An enumerated value specifying the required dimension for texture views bound to this binding. Possible values are:

  • "1d": The texture is viewed as a one-dimensional image.
  • "2d": The texture is viewed as a single two-dimensional image.
  • "2d-array": The texture is viewed as an array of two-dimensional images.
  • "cube": The texture is viewed as a cubemap. The view has 6 array layers, corresponding to the [+X, -X, +Y, -Y, +Z, -Z] faces of the cube. Sampling is done seamlessly across the faces of the cubemap.
  • "cube-array": The texture is viewed as a packed array of n cubemaps, each with 6 array layers corresponding to the [+X, -X, +Y, -Y, +Z, -Z] faces of the cube. Sampling is done seamlessly across the faces of the cubemaps.
  • "3d": The texture is viewed as a three-dimensional image.

  If omitted, viewDimension defaults to "2d".

• texture: Indicates that the corresponding GPUBindGroup entry will be a GPUTextureView object. A texture resource layout object can contain the following properties:

  multisampled Optional

  A boolean. A value of true indicates that texture views bound to this binding must be multi-sampled. If omitted, multisampled defaults to false.

  sampleType Optional

  An enumerated value specifying the sample type required for texture views bound to this binding (see GPUDevice.createTexture() for more information on texture view types). Possible values are:

  • "depth"
  • "float"
  • "sint"
  • "uint"
  • "unfilterable-float"

  If omitted, sampleType defaults to "float".

  viewDimension Optional

  An enumerated value specifying the required dimension for texture views bound to this binding. Possible and default values are the same as for storageTexture resource layout objects — see above.

A GPUBindGroupLayout object instance.

The following criteria must be met when calling createBindGroupLayout(), otherwise a GPUValidationError is generated and an invalid GPUBindGroupLayout object is returned:

• Each entry's binding value is unique.
• Each entry's binding value is less than the GPUDevice's maxBindingsPerBindGroup limit.
• The number of entries does not exceed the binding slot limits.
• Only 1 resource layout object is defined per entry.
• If an entry's visibility includes GPUShaderStage.VERTEX:
  • If its resource layout object is a buffer, its type is not "storage".
  • Its resource layout object is not a storageTexture.
• If an entry's resource layout object is a texture, and its multisampled value is true:
  • Its viewDimension is "2d".
  • Its sampleType is not "float".
• If an entry's resource layout object is a storageTexture:
  • Its viewDimension is not "cube" or "cube-array".
  • Its format is a format that supports storage usage.

Our basic compute demo shows an example of creating a bind group layout and then using that as a template when creating a bind group.

// ...

const bindGroupLayout = device.createBindGroupLayout({
  entries: [
    {
      binding: 0,
      visibility: GPUShaderStage.COMPUTE,
      buffer: {
        type: "storage",
      },
    },
  ],
});

const bindGroup = device.createBindGroup({
  layout: bindGroupLayout,
  entries: [
    {
      binding: 0,
      resource: {
        buffer: output,
      },
    },
  ],
});

// ...

• The WebGPU API