1page.title=Vulkan
2@jd:body
3
4<!--
5    Copyright 2016 The Android Open Source Project
6
7    Licensed under the Apache License, Version 2.0 (the "License");
8    you may not use this file except in compliance with the License.
9    You may obtain a copy of the License at
10
11        http://www.apache.org/licenses/LICENSE-2.0
12
13    Unless required by applicable law or agreed to in writing, software
14    distributed under the License is distributed on an "AS IS" BASIS,
15    WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
16    See the License for the specific language governing permissions and
17    limitations under the License.
18-->
19<div id="qv-wrapper">
20  <div id="qv">
21    <h2>In this document</h2>
22    <ol id="auto-toc">
23    </ol>
24  </div>
25</div>
26
27<p>Android 7.0 adds support for
28<a href="https://www.khronos.org/vulkan/">Vulkan</a>, a low-overhead,
29cross-platform API for high-performance 3D graphics. Like OpenGL ES, Vulkan
30provides tools for creating high-quality, real-time graphics in applications.
31Vulkan advantages include reductions in CPU overhead and support for the
32<a href="https://www.khronos.org/spir">SPIR-V Binary Intermediate</a> language.
33</p>
34
35<p>System on chip vendors (SoCs) such as GPU Independent Hardware Vendors (IHVs)
36can write Vulkan drivers for Android; OEMs simply need to integrate these
37drivers for specific devices. For details on how a Vulkan driver interacts with
38the system, how GPU-specific tools should be installed, and Android-specific
39requirements, see <a href="{@docRoot}devices/graphics/implement-vulkan.html">Implementing
40Vulkan.</a></p>
41
42<p>Application developers can take advantage of Vulkan to create apps that
43execute commands on the GPU with significantly reduced overhead. Vulkan also
44provides a more direct mapping to the capabilities found in current graphics
45hardware, minimizing opportunities for driver bugs and reducing developer
46testing time (e.g. less time required to troubleshoot Vulkan bugs).</p>
47
48<p>For general information on Vulkan, refer to the
49<a href="http://khr.io/vulkanlaunchoverview">Vulkan Overview</a> or see the list
50of <a href="#resources">Resources</a> below.</p>
51
52<h2 id=vulkan_components>Vulkan components</h2>
53<p>Vulkan support includes the following components:</p>
54<p><img src="{@docRoot}devices/graphics/images/ape_graphics_vulkan.png"></p>
55<p class=img-caption>Figure 1: Vulkan components</p>
56
57<ul>
58<li><strong>Vulkan Validation Layers</strong> (<em>provided in the Android
59NDK</em>). A set of libraries used by developers during the development of
60Vulkan apps. The Vulkan runtime library and the Vulkan driver from graphics
61vendors do not contain runtime error-checking to keep Vulkan runtime efficient.
62Instead, the validation libraries are used (only during development) to find
63errors in an application's use of the Vulkan API. The Vulkan Validation
64libraries are linked into the app during development and perform this error
65checking. After all API usage issues are found, the aplication no longer needs
66to include these libraries in the app.</li>
67<li><strong>Vulkan Runtime </strong><em>(provided by Android)</em>. A native
68library <code>(libvulkan.so</code>) that provides a new public native API
69called <a href="https://www.khronos.org/vulkan">Vulkan</a>. Most functionality
70is implemented by a driver provided by the GPU vendor; the runtime wraps the
71driver, provides API interception capabilities (for debugging and other
72developer tools), and manages the interaction between the driver and platform
73dependencies such as BufferQueue.</li>
74<li><strong>Vulkan Driver </strong><em>(provided by SoC)</em>. Maps the Vulkan
75API onto hardware-specific GPU commands and interactions with the kernel
76graphics driver.</li>
77</ul>
78
79<h2 id=modified_components>Modified components</h2>
80<p>Android 7.0 modifies the following existing graphics components to support
81Vulkan:</p>
82
83<ul>
84<li><strong>BufferQueue</strong>. The Vulkan Runtime interacts with the existing
85BufferQueue component via the existing <code>ANativeWindow</code> interface.
86Includes minor modifications (new enum values and new methods) to
87<code>ANativeWindow</code> and BufferQueue, but no architectural changes.</li>
88<li><strong>Gralloc HAL</strong>. Includes a new, optional interface for
89discovering whether a given format can be used for a particular
90producer/consumer combination without actually allocating a buffer.</li>
91</ul>
92
93<p>For details on these components, see
94<a href="{@docRoot}devices/graphics/arch-bq-gralloc.html">BufferQueue and
95gralloc</a> (for details on <code>ANativeWindow</code>, see
96<a href="{@docRoot}devices/graphics/arch-egl-opengl.html">EGLSurface and OpenGL
97ES</a>).
98
99<h2 id=apis>Vulkan API</h2>
100<p>The Android platform includes an
101<a href="https://developer.android.com/ndk/guides/graphics/index.html">Android-specific
102implementation</a> of the <a href="https://www.khronos.org/vulkan/">Vulkan API
103specification</a> from the Khronos Group. Android applications must use the
104<a href="{@docRoot}devices/graphics/implement-vulkan.html#wsi">Window System
105Integration (WSI) extensions</a> to output their rendering.</p>
106
107<h2 id=resources>Resources</h2>
108<p>Use the following resources to learn more about Vulkan:</p>
109<ul>
110
111<li>
112<a href="https://googleplex-android.git.corp.google.com/platform/frameworks/native/+/nyc-dr1-release/vulkan/#">Vulkan
113Loader </a>(libvulkan.so) at <code>platform/frameworks/native/vulkan</code>.
114Contains Android's Vulkan loader, as well as some Vulkan-related tools useful to
115platform developers.</li>
116
117<li><a href="https://android.googlesource.com/platform/frameworks/native/+/master/vulkan/doc/implementors_guide/implementors_guide.html">Vulkan
118Implementor's Guide</a>. Intended for GPU IHVs writing Vulkan drivers for
119Android and OEMs integrating those drivers for specific devices. It describes
120how a Vulkan driver interacts with the system, how GPU-specific tools should be
121installed, and Android-specific requirements.</li>
122
123<li><a href="https://developer.android.com/ndk/guides/graphics/index.html">Vulkan
124Graphics API Guide</a>. Includes information on getting started with using
125Vulkan in an Android app, details on Vulkan design guidelines on the Android
126platform, how to use Vulkan's shader compilers, and how to use use validation
127layers to help assure stability in apps using Vulkan.</li>
128
129<li><a href="https://www.khronos.org/#slider_vulkan">Vulkan News</a>. Covers
130events, patches, tutorials, and more Vulkan-related news articles.</li>
131</ul>
132