C.3. VK_EXT_debug_marker

Name String
VK_EXT_debug_marker
Extension Type
Device extension
Registered Extension Number
23
Last Modified Date
2016-04-23
Revision
3
IP Status
No known IP claims.
Dependencies
  • This extension is written against version 1.0.11 of the Vulkan API.
Contributors
  • Baldur Karlsson
  • Dan Ginsburg, Valve
  • Jon Ashburn, LunarG
  • Kyle Spagnoli, NVIDIA
Contacts
  • Baldur Karlsson

The VK_EXT_debug_marker extension is a device extension. It introduces concepts of object naming and tagging, for better tracking of Vulkan objects, as well as additional commands for recording annotations of named sections of a workload to aid organisation and offline analysis in external tools.

C.3.1. New Object Types

None

C.3.2. New Enum Constants

  • Extending VkStructureType:

    • VK_STRUCTURE_TYPE_DEBUG_MARKER_OBJECT_NAME_INFO_EXT
    • VK_STRUCTURE_TYPE_DEBUG_MARKER_OBJECT_TAG_INFO_EXT
    • VK_STRUCTURE_TYPE_DEBUG_MARKER_MARKER_INFO_EXT

C.3.3. New Enums

None

C.3.4. New Structures

C.3.5. New Functions

C.3.6. Examples

Example 1

Associate a name with an image, for easier debugging in external tools or with validation layers that can print a friendly name when referring to objects in error messages.

    extern VkDevice device;
    extern VkImage image;

    // Must call extension functions through a function pointer:
    PFN_vkDebugMarkerSetObjectNameEXT pfnDebugMarkerSetObjectNameEXT = (PFN_vkDebugMarkerSetObjectNameEXT)vkGetDeviceProcAddr(device, "vkDebugMarkerSetObjectNameEXT");

    // Set a name on the image
    const VkDeviceCreateInfo imageNameInfo =
    {
        VK_STRUCTURE_TYPE_DEBUG_MARKER_OBJECT_NAME_INFO_EXT, // sType
        NULL,                                           // pNext
        VK_DEBUG_REPORT_OBJECT_TYPE_IMAGE_EXT,          // objectType
        (uint64_t)image,                                // object
        "Brick Diffuse Texture",                        // pObjectName
    };

    pfnDebugMarkerSetObjectNameEXT(device, &imageNameInfo);

    // A subsequent error might print:
    //   Image 'Brick Diffuse Texture' (0xc0dec0dedeadbeef) is used in a
    //   command buffer with no memory bound to it.

Example 2

Annotating regions of a workload with naming information so that offline analysis tools can display a more usable visualisation of the commands submitted.

    extern VkDevice device;
    extern VkCommandBuffer commandBuffer;

    // Must call extension functions through a function pointer:
    PFN_vkCmdDebugMarkerBeginEXT pfnCmdDebugMarkerBeginEXT = (PFN_vkCmdDebugMarkerBeginEXT)vkGetDeviceProcAddr(device, "vkCmdDebugMarkerBeginEXT");
    PFN_vkCmdDebugMarkerEndEXT pfnCmdDebugMarkerEndEXT = (PFN_vkCmdDebugMarkerEndEXT)vkGetDeviceProcAddr(device, "vkCmdDebugMarkerEndEXT");
    PFN_vkCmdDebugMarkerInsertEXT pfnCmdDebugMarkerInsertEXT = (PFN_vkCmdDebugMarkerInsertEXT)vkGetDeviceProcAddr(device, "vkCmdDebugMarkerInsertEXT");

    // Describe the area being rendered
    const VkDebugMarkerMarkerInfoEXT houseMarker =
    {
        VK_STRUCTURE_TYPE_DEBUG_MARKER_MARKER_INFO_EXT, // sType
        NULL,                                           // pNext
        "Brick House",                                  // pMarkerName
        { 1.0f, 0.0f, 0.0f, 1.0f },                     // color
    };

    // Start an annotated group of calls under the 'Brick House' name
    pfnCmdDebugMarkerBeginEXT(commandBuffer, &houseMarker);
    {
        // A mutable structure for each part being rendered
        VkDebugMarkerMarkerInfoEXT housePartMarker =
        {
            VK_STRUCTURE_TYPE_DEBUG_MARKER_MARKER_INFO_EXT, // sType
            NULL,                                           // pNext
            NULL,                                           // pMarkerName
            { 0.0f, 0.0f, 0.0f, 0.0f },                     // color
        };

        // Set the name and insert the marker
        housePartMarker.pMarkerName = "Walls";
        pfnCmdDebugMarkerInsertEXT(commandBuffer, &housePartMarker);

        // Insert the drawcall for the walls
        vkCmdDrawIndexed(commandBuffer, 1000, 1, 0, 0, 0);

        // Insert a recursive region for two sets of windows
        housePartMarker.pMarkerName = "Windows";
        pfnCmdDebugMarkerBeginEXT(commandBuffer, &housePartMarker);
        {
            vkCmdDrawIndexed(commandBuffer, 75, 6, 1000, 0, 0);
            vkCmdDrawIndexed(commandBuffer, 100, 2, 1450, 0, 0);
        }
        pfnCmdDebugMarkerEndEXT(commandBuffer);

        housePartMarker.pMarkerName = "Front Door";
        pfnCmdDebugMarkerInsertEXT(commandBuffer, &housePartMarker);

        vkCmdDrawIndexed(commandBuffer, 350, 1, 1650, 0, 0);

        housePartMarker.pMarkerName = "Roof";
        pfnCmdDebugMarkerInsertEXT(commandBuffer, &housePartMarker);

        vkCmdDrawIndexed(commandBuffer, 500, 1, 2000, 0, 0);
    }
    // End the house annotation started above
    pfnCmdDebugMarkerEndEXT(commandBuffer);

C.3.7. Issues

1) Should the tag or name for an object be specified using the pNext parameter in the object’s CreateInfo structure?

RESOLVED: No.
While this fits with other Vulkan patterns and would allow more type
safety and future proofing against future objects, it has notable
downsides.
In particular passing the name at CreateInfo time does not allow
renaming, prevents late binding of naming information, and does not allow
naming of implicitly created objects such as queues and swap chain
images.

2) Should the command annotation functions vkCmdDebugMarkerBeginEXT() and vkCmdDebugMarkerEndEXT() support the ability to specify a color?

RESOLVED: Yes.
The functions have been expanded to take an optional color which can be
used at will by implementations consuming the command buffer annotations
in their visualisation.

3) Should the functions added in this extension accept an extensible structure as their parameter for a more flexible API, as opposed to direct function parameters? If so, which functions?

RESOLVED: Yes.
All functions have been modified to take a structure type with extensible
pNext pointer, to allow future extensions to add additional annotation
information in the same commands.

C.3.8. Version History

  • Revision 1, 2015-02-24 (Baldur Karlsson)

    • Initial draft, based on LunarG marker spec
  • Revision 2, 2015-02-26 (Baldur Karlsson)

    • Renamed Dbg to DebugMarker in function names
    • Allow markers in secondary command buffers under certain circumstances
    • Minor language tweaks and edits
  • Revision 3, 2015-04-23 (Baldur Karlsson)

    • Reorganise spec layout to closer match desired organisation
    • Added optional color to markers (both regions and inserted labels)
    • Changed functions to take extensible structs instead of direct function parameters