{"id":9522,"date":"2024-05-16T09:36:11","date_gmt":"2024-05-16T16:36:11","guid":{"rendered":"https:\/\/devblogs.microsoft.com\/directx\/?p=9522"},"modified":"2024-05-16T14:01:39","modified_gmt":"2024-05-16T21:01:39","slug":"agility-sdk-1-614-0","status":"publish","type":"post","link":"https:\/\/devblogs.microsoft.com\/directx\/agility-sdk-1-614-0\/","title":{"rendered":"Agility SDK 1.614.0: R9B9G9E5 support for Render Targets and UAVs"},"content":{"rendered":"

Today the DirectX team is excited to announce the release of the Agility SDK 1.614.0 which includes full support for R9G9B9E5_SHAREDEXP (999E5) texture format for render targets and UAV read\/writes! This new Agility SDK is also fully supported by PIX.<\/p>\n

To get the latest release head on over to our Agility SDK downloads page<\/a>.<\/p>\n

Understanding the 999E5 Texture Format<\/h3>\n

999E5 was originally introduced in Direct3D 11<\/a> and Direct3D 12 in a limited capacity. Its Direct3D 12 support has now been extended to support render targets and UAVs.\u00a0 A key benefit of the 999E5 texture format is it enables efficient storage and rendering of certain types of content in real-time computer graphics applications, such as video games and simulations. It is part of a family of texture formats that balance between storage space and rendering performance, crucial for delivering immersive visual experiences while keeping resource usage in check.<\/p>\n

As for how the format works, 999E5 format represents color values using a shared exponent among the RGB components (Red, Green, Blue). It provides some of the benefits of floating-point representation while using fewer bits than traditional formats (e.g., FP32 or FP16). Despite its space efficiency, the 999E5 format retains a higher dynamic range compared to half-precision formats.<\/p>\n

Advantages of 999E5 Texture Format<\/h3>\n
    \n
  1. Storage Efficiency<\/strong>: One of the primary benefits of the 999E5 format is its efficiency of storage. For example, traditional floating-point format FP 16 consumes 64 bits per pixel, while 999E5 consumes 32 bits per pixel.<\/li>\n
  2. Visual Fidelity<\/strong>: Despite its compression, the 999E5 format retains a higher dynamic range than FP 16. The tradeoff is the lack of a sign bit and an alpha channel.<\/li>\n<\/ol>\n

    To use 999E5, applications need to create their render target and unordered access views of resources in the appropriate format. This would be the same way applications use DXGI_FORMAT_R32G32B32A32_UINT, or any other format that does not require casting to use.<\/p>\n

    Because of the hardware support ecosystem, it is recommended to always check if a driver\/hardware combination supports 999E5. The code below is how an application can query the runtime to check for the upgraded support.<\/p>\n

    D3D12_FEATURE_DATA_FORMAT_SUPPORT formatSupport{};\r\nformatSupport.Format = DXGI_FORMAT_R9G9B9E5_SHAREDEXP;\r\n\r\nm_device->CheckFeatureSupport(\r\n    D3D12_FEATURE_FORMAT_SUPPORT, \r\n    &formatSupport, \r\n    sizeof(D3D12_FEATURE_DATA_FORMAT_SUPPORT));\r\n\r\nif (formatSupport.Support1 & D3D12_FORMAT_SUPPORT1_RENDER_TARGET)\r\n{\r\n\u00a0\u00a0\u00a0 \/\/ Since it is all-or-nothing, supporting render target \r\n    \/\/ means support updated 999E5 revision\r\n\u00a0\u00a0\u00a0 printf(\"Format supports rtv and uav\\n\");\r\n}<\/code><\/pre>\n
    We are also working hard on making this format be swap chain compatible, and applications will be able to use 999E5 in their Present pipelines in the future.<\/p>\n
    For more up-to-date technical information, please refer to the D3D12 R9B9G9E5 spec<\/a>.<\/p>\n
    PIX Support<\/h3>\n
    Agility SDK 1.614 has day 0 PIX support.\u00a0 To get the latest PIX that supports this SDK and to learn more about what is included in this PIX update please the latest PIX 2405-15 blog post<\/a>.<\/p>\n
    Driver Availability<\/h2>\n