TheWGSLLanguageFeatures interface of theWebGPU API is asetlike object that reports theWGSL language extensions supported by the WebGPU implementation.

TheWGSLLanguageFeatures object is accessed via theGPU.wgslLanguageFeatures property.

Available features

The following WGSL language extensions are defined atWGSL language extensions in the WGSL specification. Bear in mind that the exact set of features available will vary across implementations and physical devices, and may change over time.

packed_4x8_integer_dot_product

AllowsDP4a (Dot Product of 4 Elements and Accumulate) GPU instructions to be used via your WGSL code. These efficiently perform 8-bit integer dot products to accelerate computation, saving memory and network bandwidth and improving performance compared with the equivalentf32 versions. They are commonly used in machine learning models in inferencing, within AI frameworks.

Specifically, whenpacked_4x8_integer_dot_product is available, WGSL code can use:

• 32-bit integer scalars packing 4-component vectors of 8-bit integers to be used as inputs to dot product instructions (via thedot4U8Packed() anddot4I8Packed() built-in functions).
• Packing and unpacking instructions with packed 4-component vectors of 8-bit integers (via built-in functions such aspack4xI8() andpack4xI8Clamp()).

pointer_composite_access

Enables WGSL shader code to access components of complex data types using the same dot (.) syntax whether you're working directly with the data or with a pointer to it.

Whenpointer_composite_access is available:

• Iffoo is a pointer:foo.bar is available as a more convenient way to write(*foo).bar. The asterisk (*) would normally be needed to turn the pointer into a "reference" that can be dereferenced, but now both pointers and references are almost interchangeable.
• Iffoo is not a pointer: The dot (.) operator works exactly as you're used to for directly accessing members.
• ifpa is a pointer that stores the starting address of an array, thenpa[i] gives you direct access to the memory location where theith element of that array is stored.

SeeSyntax sugar for dereferencing composites in WGSL for further details and an example.

readonly_and_readwrite_storage_textures

When available, allows the"read-only" and"read-write"storageTexture.access values to be set when specifying storage texture bind group entry types in a bind group layout. These enable WGSL code to read storage textures, and read/write storage textures, respectively.

unrestricted_pointer_parameters

Loosens restrictions on pointers being passed to WGSL functions. When available, the following are allowed:

• Parameter pointers to storage, uniform, and workgroup address spaces being passed to user-declared functions.

• Pointers to structure members and array elements being passed to user-declared functions.

  SeePointers As Function Parameters for more details.

Instance properties

The following property is available to all read-onlysetlike objects:

size

Returns the number of values in the set.

Instance methods

The following methods are available to all read-onlysetlike objects:

has()

Returns a boolean asserting whether or not an element with the given value is present in the set.

values()

Returns a new iterator object that yieldsvalues for each element in the set in insertion order.

keys()

An alias forvalues().

entries()

Returns a new iterator object that containsan array of[value, value] for each element in the set in insertion order.

forEach()

Calls the provided callback function once for each value present in the set in insertion order.

Examples

Check whether an extension is available

if (  navigator.gpu.wgslLanguageFeatures.has(    "readonly_and_readwrite_storage_textures",  )) {  console.log("Read-only and read-write storage textures are available");}

Return set size and iterate through values

const wgslFeatures = navigator.gpu.wgslLanguageFeatures;// Return the size of the setconsole.log(wgslFeatures.size);// Iterate through all the set values using values()const valueIterator = wgslFeatures.values();for (const value of valueIterator) {  console.log(value);}// …

Specifications

Browser compatibility

See also

• WebGPU API