Struct PrivateCapabilities

struct PrivateCapabilities {

    image_view_usage: bool,
    timeline_semaphores: bool,
    texture_d24: bool,
    texture_d24_s8: bool,
    texture_s8: bool,
    can_present: bool,
    non_coherent_map_mask: BufferAddress,
    multi_draw_indirect: bool,
    robust_buffer_access: bool,
    robust_image_access: bool,
    robust_buffer_access2: bool,
    robust_image_access2: bool,
    zero_initialize_workgroup_memory: bool,
    image_format_list: bool,
    maximum_samplers: u32,
    shader_integer_dot_product: bool,
    shader_int8: bool,
    multiview_instance_index_limit: u32,
}

Set of internal capabilities, which don’t show up in the exposed device geometry, but affect the code paths taken internally.

Fields

image_view_usage: bool

timeline_semaphores: bool

texture_d24: bool

texture_d24_s8: bool

texture_s8: bool

can_present: bool

Ability to present contents to any screen. Only needed to work around broken platform configurations.

non_coherent_map_mask: BufferAddress

multi_draw_indirect: bool

robust_buffer_access: bool

True if this adapter advertises the robustBufferAccess feature.

Note that Vulkan’s robustBufferAccess is not sufficient to implement wgpu_hal’s guarantee that shaders will not access buffer contents via a given bindgroup binding outside that binding’s accessible region. Enabling robustBufferAccess does ensure that out-of-bounds reads and writes are not undefined behavior (that’s good), but still permits out-of-bounds reads to return data from anywhere within the buffer, not just the accessible region.

robust_image_access: bool

robust_buffer_access2: bool

True if this adapter supports the VK_EXT_robustness2 extension’s robustBufferAccess2 feature.

This is sufficient to implement wgpu_hal’s required bounds-checking of shader accesses to buffer contents. If this feature is not available, this backend must have Naga inject bounds checks in the generated SPIR-V.

robust_image_access2: bool

zero_initialize_workgroup_memory: bool

image_format_list: bool

maximum_samplers: u32

shader_integer_dot_product: bool

True if this adapter supports the VK_KHR_shader_integer_dot_product extension (promoted to Vulkan 1.3).

This is used to generate optimized code for WGSL’s dot4{I, U}8Packed.

shader_int8: bool

True if this adapter supports 8-bit integers provided by the VK_KHR_shader_float16_int8 extension (promoted to Vulkan 1.2).

Allows shaders to declare the “Int8” capability. Note, however, that this feature alone allows the use of 8-bit integers “only in the Private, Workgroup (for non-Block variables), and Function storage classes” (see spec). To use 8-bit integers in the interface storage classes (e.g., StorageBuffer), you also need to enable the corresponding feature in VkPhysicalDevice8BitStorageFeatures and declare the corresponding SPIR-V capability (e.g., StorageBuffer8BitAccess).

multiview_instance_index_limit: u32

This is done to panic before undefined behavior, and is imperfect. Basically, to allow implementations to emulate mv using instancing, if you want to draw n instances to VR, you must draw 2n instances, but you can never draw more than u32::MAX instances. Therefore, when drawing multiview on some vulkan implementations, it might restrict the instance count, which isn’t usually a thing in webgpu. We don’t expose this limit because its strange, i.e. only occurs on certain vulkan implementations if you are drawing more than 128 million instances. We still want to avoid undefined behavior in this situation, so we panic if the limit is violated.

Implementations

impl PrivateCapabilities

pub fn map_texture_format(&self, format: TextureFormat) -> Format

Trait Implementations

impl Clone for PrivateCapabilities

fn clone(&self) -> PrivateCapabilities

Returns a copy of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for PrivateCapabilities

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.