VkDebugReportCallbackEXT

VkDebugReportCallbackEXT is a component of the Vulkan VK_EXT_debug_report extension that provides a callback-based mechanism for receiving diagnostic messages from the Vulkan implementation and layers. It is intended to aid debugging by delivering errors, warnings, and informational messages during a application's interaction with Vulkan.

The extension introduces several core elements. The callback type is PFN_vkDebugReportCallbackEXT, a function pointer with a signature that receives details such as the message flags (VkDebugReportFlagsEXT), the object type involved (VkDebugReportObjectTypeEXT), an object handle, a location, a message code, and the actual message text along with the layer prefix. A VkDebugReportCallbackCreateInfoEXT structure specifies the callback function, user data, and the desired message severities and types to report. A VkDebugReportCallbackEXT handle is returned when creating the callback via vkCreateDebugReportCallbackEXT and must be destroyed with vkDestroyDebugReportCallbackEXT when no longer needed. The extension also provides vkDebugReportMessageEXT to manually post a message.

Typical usage involves enabling VK_EXT_debug_report during instance creation, constructing a VkDebugReportCallbackCreateInfoEXT with the desired flags (for example, VK_DEBUG_REPORT_ERROR_BIT_EXT, VK_DEBUG_REPORT_WARNING_BIT_EXT) and types, and calling vkCreateDebugReportCallbackEXT to register the callback. The application then handles incoming messages in the callback and usually returns VK_FALSE to indicate that message handling should not terminate the application.

Although VK_EXT_debug_report is still used, many developers prefer VK_EXT_debug_utils for modern debugging and messaging features. VkDebugReportCallbackEXT remains relevant for compatibility with older codebases and validation layers.