Book Image

Vulkan Cookbook

By : Pawel Lapinski
Book Image

Vulkan Cookbook

By: Pawel Lapinski

Overview of this book

Vulkan is the next generation graphics API released by the Khronos group. It is expected to be the successor to OpenGL and OpenGL ES, which it shares some similarities with such as its cross-platform capabilities, programmed pipeline stages, or nomenclature. Vulkan is a low-level API that gives developers much more control over the hardware, but also adds new responsibilities such as explicit memory and resources management. With it, though, Vulkan is expected to be much faster. This book is your guide to understanding Vulkan through a series of recipes. We start off by teaching you how to create instances in Vulkan and choose the device on which operations will be performed. You will then explore more complex topics such as command buffers, resources and memory management, pipelines, GLSL shaders, render passes, and more. Gradually, the book moves on to teach you advanced rendering techniques, how to draw 3D scenes, and how to improve the performance of your applications. By the end of the book, you will be familiar with the latest advanced techniques implemented with the Vulkan API, which can be used on a wide range of platforms.
Table of Contents (13 chapters)

Destroying a logical device

After we have finished and we want to quit the application, we should clean up after ourselves. Despite the fact that all the resources should be destroyed automatically by the driver when the Vulkan Instance is destroyed, we should also do this explicitly in the application to follow good programming guidelines. The order of destroying resources should be opposite to the order in which they were created.

Resources should be released in the reverse order to the order of their creation.

In this chapter, the logical device was the last created object, so it will be destroyed first.

How to do it...

  1. Take the handle of the logical device that was created and stored in a variable of type VkDevice named logical_device.
  2. Call vkDestroyDevice( logical_device, nullptr ); provide the logical_device variable in the first argument, and a nullptr value in the second.
  3. For safety reasons, assign the VK_NULL_HANDLE value to the logical_device variable.

How it works...

The implementation of the logical device-destroying recipe is very straightforward:

if( logical_device ) { 
  vkDestroyDevice( logical_device, nullptr ); 
  logical_device = VK_NULL_HANDLE; 
}

First, we need to check if the logical device handle is valid, because, we shouldn't destroy objects that weren't created. Then, we destroy the device with the vkDestroyDevice() function call and we assign the VK_NULL_HANDLE value to the variable in which the logical device handle was stored. We do this just in case--if there is a mistake in our code, we won't destroy the same object twice.

Remember that, when we destroy a logical device, we can't use device-level functions acquired from it.

See also

  • The recipe Creating a logical device in this chapter