Edit

Displayable surfaces

  • Article

Before displayable surfaces, presentation was generally done by creating a swap chain of buffers with identical properties, which were then cycled (flipped) through repeatedly, in order, to be presented to the screen. If you wanted to change the properties of a buffer to be presented, then you had to destroy that swap chain, and create a new one with all the buffers updated to the same new properties.

The displayable surfaces feature adds new operating system (OS) behavior that eliminates those restrictions (but it requires driver support in order to behave properly). Specifically, the feature means that buffers that are presented may have varying properties, and you may present them in any order.

The displayable surfaces (and flexible presentation) features, and their APIs, were introduced in Windows 11 (Build 10.0.22000.194). The functionality is enabled on supported drivers, beginning with WDDM 3.0 drivers, enabling enhanced presentation scenarios for Direct3D 11.

Check for support, and use displayable surfaces

To determine whether the displayable surfaces feature is available on a system, call ID3D11Device::CheckFeatureSupport. Pass D3D11_FEATURE::D3D11_FEATURE_DISPLAYABLE, and receive a D3D11_FEATURE_DATA_DISPLAYABLE structure.

The ID3D11Device::CreateTexture2D API supports D3D11_RESOURCE_MISC_FLAG::D3D11_RESOURCE_MISC_SHARED_DISPLAYABLE, which you can use in the D3D11_TEXTURE2D_DESC::MiscFlags member of the structure that you pass to CreateTexture2D in the pDesc parameter.

Textures with D3D11_RESOURCE_MISC_SHARED_DISPLAYABLE are restricted to an array size of 1, and to 1 mip level.

When you use the D3D11_RESOURCE_MISC_SHARED_DISPLAYABLE flag on the texture, you can show the texture on any active output (including multiple outputs simultaneously). Depending on the scenario, the texture might end up being consumed by the compositor (DWM), scanned out, or bound to various parts of the pipeline—potentially all simultaneously. For example, a capture texture from a camera might be shown on two displays, and a thumbnail of it shown on a third display, all at the same time—and all from the same allocation with no additional copies. In the case where a displayable surface is to be scanned out on multiple displays, the OS will coordinate the collection of flip completes from the involved outputs before alerting your application that the surface is released back to it—no coordination of flip completion is required from the driver.

Such textures as described above must be displayable for flexible presentation use. These textures are not required to have the same properties—for example, formats and sizes can differ, and these textures must be able to be displayed in arbitrary order ("out-of-order presentation"). Presentation will occur using the existing Present1 DDI, with its existing calling patterns. For example, consider a pool of six buffers, three that are 720p (A, B, and C) and three that are 4K (D, E, and F): a valid presentation order could be A->E->C->B->F->E->D->C.

Formats

The D3D11_RESOURCE_MISC_SHARED_DISPLAYABLE flag is supported for the following formats in Direct3D 11:

A driver might also, optionally, support the following formats:

  • DXGI_FORMAT_P010

You can use the following code example to check for displayable surfaces support for the optional formats above. The example involves calling ID3D11Device::CheckFeatureSupport, and checking for D3D11_FEATURE_FORMAT_SUPPORT2.

D3D11_FEATURE_DATA_FORMAT_SUPPORT2 FormatSupport2;
FormatSupport2.InFormat = DXGI_FORMAT_P010;
if (SUCCEEDED (hr = GetDevice()->CheckFeatureSupport(D3D11_FEATURE_FORMAT_SUPPORT2, &FormatSupport2, sizeof(FormatSupport2))))
{
    if (FormatSupport2.OutFormatSupport2 & D3D11_FORMAT_SUPPORT2_DISPLAYABLE)
    {
        // optional displayable format is supported
    }
}

Flags

Shareable formats already generally support the following bind flags: D3D11_BIND_FLAG::D3D11_BIND_SHADER_RESOURCE, D3D11_BIND_UNORDERED_ACCESS, D3D11_BIND_RENDER_TARGET, and D3D11_BIND_DECODER.

Existing supported usages of shared resources with the D3D11_BIND_VIDEO_ENCODER flag are extended to also support the D3D11_RESOURCE_MISC_SHARED_DISPLAYABLE flag being added in these cases. Existing restrictions related to use of shared resources with D3D11_BIND_VIDEO_ENCODER are maintained.

D3D11_BIND_VIDEO_ENCODER and D3D11_BIND_SHADER_RESOURCE were previously mutually exclusive, except when combined with certain other bind flags. The exception has been extended to allow D3D11_BIND_VIDEO_ENCODER and D3D11_BIND_SHADER_RESOURCE to be used together when D3D11_RESOURCE_MISC_SHARED_DISPLAYABLE is used.

The D3D11_RESOURCE_MISC_HW_PROTECTED flag is supported with the D3D11_RESOURCE_MISC_SHARED_DISPLAYABLE flag.