vkGetSwapchainImagesKHR

vkGetSwapchainImagesKHR is a Vulkan device-level command that retrieves the array of VkImage handles backing a swapchain. It is provided as part of the VK_KHR_swapchain extension and is essential for obtaining the actual images the presentation engine will display.

Usage typically follows a two-step pattern. First, call the function with pSwapchainImageCount pointing to a zero-initialized uint32_t and pSwapchainImages set to NULL. The function writes the required number of swapchain images into *pSwapchainImageCount. Next, allocate an array of VkImage with that size and call the function again with pSwapchainImages pointing to the array; the function fills it with the swapchain image handles. The retrieved images are the actual color buffers used for presentation and can be bound to image views and framebuffers for rendering. They are owned by the swapchain and their lifetime is tied to the swapchain.

The parameters are: device (the logical device), swapchain (the swapchain to query), pSwapchainImageCount (in/out count of images), and pSwapchainImages (array to be filled with the VkImage handles). On success, VK_SUCCESS is returned; otherwise, a negative VkResult such as VK_ERROR_OUT_OF_HOST_MEMORY or VK_ERROR_OUT_OF_DEVICE_MEMORY may be returned.

Notes and considerations include that the number and identity of swapchain images are determined when the swapchain is created and may change if the swapchain is recreated (for example, after a resize). After recreation, vkGetSwapchainImagesKHR must be called again to obtain the new set of images. The retrieved images are presented via present operations and are typically used to create corresponding image views and framebuffers for rendering.