mirror of
https://github.com/GPUOpen-LibrariesAndSDKs/VulkanMemoryAllocator.git
synced 2024-11-10 10:41:52 +00:00
162 lines
9.2 KiB
HTML
162 lines
9.2 KiB
HTML
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
|
|
<html xmlns="http://www.w3.org/1999/xhtml">
|
|
<head>
|
|
<meta http-equiv="Content-Type" content="text/xhtml;charset=UTF-8"/>
|
|
<meta http-equiv="X-UA-Compatible" content="IE=9"/>
|
|
<meta name="generator" content="Doxygen 1.8.13"/>
|
|
<meta name="viewport" content="width=device-width, initial-scale=1"/>
|
|
<title>Vulkan Memory Allocator: Vulkan Memory Allocator</title>
|
|
<link href="tabs.css" rel="stylesheet" type="text/css"/>
|
|
<script type="text/javascript" src="jquery.js"></script>
|
|
<script type="text/javascript" src="dynsections.js"></script>
|
|
<link href="search/search.css" rel="stylesheet" type="text/css"/>
|
|
<script type="text/javascript" src="search/searchdata.js"></script>
|
|
<script type="text/javascript" src="search/search.js"></script>
|
|
<link href="doxygen.css" rel="stylesheet" type="text/css" />
|
|
</head>
|
|
<body>
|
|
<div id="top"><!-- do not remove this div, it is closed by doxygen! -->
|
|
<div id="titlearea">
|
|
<table cellspacing="0" cellpadding="0">
|
|
<tbody>
|
|
<tr style="height: 56px;">
|
|
<td id="projectalign" style="padding-left: 0.5em;">
|
|
<div id="projectname">Vulkan Memory Allocator
|
|
</div>
|
|
</td>
|
|
</tr>
|
|
</tbody>
|
|
</table>
|
|
</div>
|
|
<!-- end header part -->
|
|
<!-- Generated by Doxygen 1.8.13 -->
|
|
<script type="text/javascript">
|
|
var searchBox = new SearchBox("searchBox", "search",false,'Search');
|
|
</script>
|
|
<script type="text/javascript" src="menudata.js"></script>
|
|
<script type="text/javascript" src="menu.js"></script>
|
|
<script type="text/javascript">
|
|
$(function() {
|
|
initMenu('',true,false,'search.php','Search');
|
|
$(document).ready(function() { init_search(); });
|
|
});
|
|
</script>
|
|
<div id="main-nav"></div>
|
|
</div><!-- top -->
|
|
<!-- window showing the filter options -->
|
|
<div id="MSearchSelectWindow"
|
|
onmouseover="return searchBox.OnSearchSelectShow()"
|
|
onmouseout="return searchBox.OnSearchSelectHide()"
|
|
onkeydown="return searchBox.OnSearchSelectKey(event)">
|
|
</div>
|
|
|
|
<!-- iframe showing the search results (closed by default) -->
|
|
<div id="MSearchResultsWindow">
|
|
<iframe src="javascript:void(0)" frameborder="0"
|
|
name="MSearchResults" id="MSearchResults">
|
|
</iframe>
|
|
</div>
|
|
|
|
<div class="header">
|
|
<div class="headertitle">
|
|
<div class="title">Vulkan Memory Allocator </div> </div>
|
|
</div><!--header-->
|
|
<div class="contents">
|
|
<div class="textblock"><p>Version 2.0.0-alpha.2 (2017-07-11)</p>
|
|
<p>Members grouped: see <a href="modules.html"><b>Modules</b></a>.</p>
|
|
<p>All members: see <a class="el" href="vk__mem__alloc_8h.html">vk_mem_alloc.h</a>.</p>
|
|
<h1><a class="anchor" id="problem"></a>
|
|
Problem Statement</h1>
|
|
<p>Memory allocation and resource (buffer and image) creation in Vulkan is difficult (comparing to older graphics API-s, like D3D11 or OpenGL) for several reasons:</p>
|
|
<ul>
|
|
<li>It requires a lot of boilerplate code, just like everything else in Vulkan, because it is a low-level and high-performance API.</li>
|
|
<li>There is additional level of indirection: VkDeviceMemory is allocated separately from creating VkBuffer/VkImage and they must be bound together. The binding cannot be changed later - resource must be recreated.</li>
|
|
<li>Driver must be queried for supported memory heaps and memory types. Different IHV-s provide different types of it.</li>
|
|
<li>It is recommended practice to allocate bigger chunks of memory and assign parts of them to particular resources.</li>
|
|
</ul>
|
|
<h1><a class="anchor" id="features"></a>
|
|
Features</h1>
|
|
<p>This library is helps game developers to manage memory allocations and resource creation by offering some higher-level functions. Features of the library could be divided into several layers, low level to high level:</p>
|
|
<ol type="1">
|
|
<li>Functions that help to choose correct and optimal memory type based on intended usage of the memory.<ul>
|
|
<li>Required or preferred traits of the memory are expressed using higher-level description comparing to Vulkan flags.</li>
|
|
</ul>
|
|
</li>
|
|
<li>Functions that allocate memory blocks, reserve and return parts of them (VkDeviceMemory + offset + size) to the user.<ul>
|
|
<li>Library keeps track of allocated memory blocks, used and unused ranges inside them, finds best matching unused ranges for new allocations, takes all the rules of alignment into consideration.</li>
|
|
</ul>
|
|
</li>
|
|
<li>Functions that can create an image/buffer, allocate memory for it and bind them together - all in one call.</li>
|
|
</ol>
|
|
<h1><a class="anchor" id="prequisites"></a>
|
|
Prequisites</h1>
|
|
<ul>
|
|
<li>Self-contained C++ library in single header file. No external dependencies other than standard C and C++ library and of course Vulkan.</li>
|
|
<li>Public interface in C, in same convention as Vulkan API. Implementation in C++.</li>
|
|
<li>Interface documented using Doxygen-style comments.</li>
|
|
<li>Platform-independent, but developed and tested on Windows using Visual Studio.</li>
|
|
<li>Error handling implemented by returning VkResult error codes - same way as in Vulkan.</li>
|
|
</ul>
|
|
<h1><a class="anchor" id="quick_start"></a>
|
|
Quick Start</h1>
|
|
<p>In your project code:</p>
|
|
<ol type="1">
|
|
<li>Include "vk_mem_alloc.h" file wherever you want to use the library.</li>
|
|
<li>In exacly one C++ file define following macro before include to build library implementation.</li>
|
|
</ol>
|
|
<pre class="fragment">#define VMA_IMPLEMENTATION
|
|
#include "vk_mem_alloc.h"
|
|
</pre><p>At program startup:</p>
|
|
<ol type="1">
|
|
<li>Initialize Vulkan to have VkPhysicalDevice and VkDevice object.</li>
|
|
<li>Fill <a class="el" href="struct_vma_allocator_create_info.html" title="Description of a Allocator to be created. ">VmaAllocatorCreateInfo</a> structure and create VmaAllocator object by calling <a class="el" href="group__general.html#ga200692051ddb34240248234f5f4c17bb" title="Creates Allocator object. ">vmaCreateAllocator()</a>.</li>
|
|
</ol>
|
|
<pre class="fragment">VmaAllocatorCreateInfo allocatorInfo = {};
|
|
allocatorInfo.physicalDevice = physicalDevice;
|
|
allocatorInfo.device = device;
|
|
|
|
VmaAllocator allocator;
|
|
vmaCreateAllocator(&allocatorInfo, &allocator);
|
|
</pre><p>When you want to create a buffer or image:</p>
|
|
<ol type="1">
|
|
<li>Fill VkBufferCreateInfo / VkImageCreateInfo structure.</li>
|
|
<li>Fill <a class="el" href="struct_vma_memory_requirements.html">VmaMemoryRequirements</a> structure.</li>
|
|
<li>Call <a class="el" href="group__layer3.html#ga2f711e32e95cf9bf8dff4917230c2e9b">vmaCreateBuffer()</a> / <a class="el" href="group__layer3.html#ga9e34bc318ff4b25d1958e79b9db3f1aa" title="Function similar to vmaCreateBuffer(). ">vmaCreateImage()</a> to get VkBuffer/VkImage with memory already allocated and bound to it.</li>
|
|
</ol>
|
|
<pre class="fragment">VkBufferCreateInfo bufferInfo = { VK_STRUCTURE_TYPE_BUFFER_CREATE_INFO };
|
|
bufferInfo.size = myBufferSize;
|
|
bufferInfo.usage = VK_BUFFER_USAGE_VERTEX_BUFFER_BIT | VK_BUFFER_USAGE_TRANSFER_DST_BIT;
|
|
|
|
VmaMemoryRequirements memReq = {};
|
|
memReq.usage = VMA_MEMORY_USAGE_GPU_ONLY;
|
|
|
|
VkBuffer buffer;
|
|
VmaAllocation allocation;
|
|
vmaCreateBuffer(allocator, &bufferInfo, &memReq, &buffer, &allocation, nullptr);
|
|
</pre><p>Don't forget to destroy your objects:</p>
|
|
<pre class="fragment">vmaDestroyBuffer(allocator, buffer, allocation);
|
|
vmaDestroyAllocator(allocator);
|
|
</pre><h1><a class="anchor" id="configuration"></a>
|
|
Configuration</h1>
|
|
<p>Please check "CONFIGURATION SECTION" in the code to find macros that you can define before each #include of this file or change directly in this file to provide your own implementation of basic facilities like assert, min and max functions, mutex etc. C++ STL is used by default, but changing these allows you to get rid of any STL usage if you want, as many game developers tend to do.</p>
|
|
<h1><a class="anchor" id="custom_memory_allocator"></a>
|
|
Custom memory allocator</h1>
|
|
<p>You can use custom memory allocator by filling optional member <a class="el" href="struct_vma_allocator_create_info.html#a6e409087e3be55400d0e4ccbe43c608d" title="Custom allocation callbacks. ">VmaAllocatorCreateInfo::pAllocationCallbacks</a>. These functions will be passed to Vulkan, as well as used by the library itself to make any CPU-side allocations.</p>
|
|
<h1><a class="anchor" id="thread_safety"></a>
|
|
Thread safety</h1>
|
|
<ul>
|
|
<li>The library has no global state, so separate VmaAllocator objects can be used independently.</li>
|
|
<li>By default, all calls to functions that take VmaAllocator as first parameter are safe to call from multiple threads simultaneously because they are synchronized internally when needed.</li>
|
|
<li>When the allocator is created with VMA_ALLOCATOR_EXTERNALLY_SYNCHRONIZED_BIT flag, calls to functions that take such VmaAllocator object must be synchronized externally.</li>
|
|
<li>Access to a VmaAllocation object must be externally synchronized. For example, you must not call <a class="el" href="group__layer2.html#ga86dd08aba8633bfa4ad0df2e76481d8b" title="Returns current information about specified allocation. ">vmaGetAllocationInfo()</a> and <a class="el" href="group__layer2.html#ga6aced90fcc7b39882b6654a740a0b9bb" title="Compacts memory by moving allocations. ">vmaDefragment()</a> from different threads at the same time if you pass the same VmaAllocation object to these functions. </li>
|
|
</ul>
|
|
</div></div><!-- contents -->
|
|
<!-- start footer part -->
|
|
<hr class="footer"/><address class="footer"><small>
|
|
Generated by  <a href="http://www.doxygen.org/index.html">
|
|
<img class="footer" src="doxygen.png" alt="doxygen"/>
|
|
</a> 1.8.13
|
|
</small></address>
|
|
</body>
|
|
</html>
|