Added documentation chapter "Versioning and compatibility"

This commit is contained in:
Adam Sawicki 2022-02-26 13:26:44 +01:00
parent a0376f7261
commit 647f109a84
9 changed files with 74 additions and 40 deletions

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@ -101,15 +101,15 @@ Custom CPU memory allocator</h1>
<div class="line"> </div>
<div class="line"><a class="code hl_class" href="class_d3_d12_m_a_1_1_allocator.html">D3D12MA::Allocator</a>* allocator;</div>
<div class="line">HRESULT hr = <a class="code hl_function" href="namespace_d3_d12_m_a.html#ab7a1cd1683986d75ce1488b0920f4cb0">D3D12MA::CreateAllocator</a>(&amp;allocatorDesc, &amp;allocator);</div>
<div class="ttc" id="aclass_d3_d12_m_a_1_1_allocator_html"><div class="ttname"><a href="class_d3_d12_m_a_1_1_allocator.html">D3D12MA::Allocator</a></div><div class="ttdoc">Represents main object of this library initialized for particular ID3D12Device.</div><div class="ttdef"><b>Definition:</b> D3D12MemAlloc.h:789</div></div>
<div class="ttc" id="aclass_d3_d12_m_a_1_1_allocator_html"><div class="ttname"><a href="class_d3_d12_m_a_1_1_allocator.html">D3D12MA::Allocator</a></div><div class="ttdoc">Represents main object of this library initialized for particular ID3D12Device.</div><div class="ttdef"><b>Definition:</b> D3D12MemAlloc.h:790</div></div>
<div class="ttc" id="anamespace_d3_d12_m_a_html_ab7a1cd1683986d75ce1488b0920f4cb0"><div class="ttname"><a href="namespace_d3_d12_m_a.html#ab7a1cd1683986d75ce1488b0920f4cb0">D3D12MA::CreateAllocator</a></div><div class="ttdeci">D3D12MA_API HRESULT CreateAllocator(const ALLOCATOR_DESC *pDesc, Allocator **ppAllocator)</div><div class="ttdoc">Creates new main D3D12MA::Allocator object and returns it through ppAllocator.</div></div>
<div class="ttc" id="astruct_d3_d12_m_a_1_1_a_l_l_o_c_a_t_i_o_n___c_a_l_l_b_a_c_k_s_html"><div class="ttname"><a href="struct_d3_d12_m_a_1_1_a_l_l_o_c_a_t_i_o_n___c_a_l_l_b_a_c_k_s.html">D3D12MA::ALLOCATION_CALLBACKS</a></div><div class="ttdoc">Custom callbacks to CPU memory allocation functions.</div><div class="ttdef"><b>Definition:</b> D3D12MemAlloc.h:184</div></div>
<div class="ttc" id="astruct_d3_d12_m_a_1_1_a_l_l_o_c_a_t_i_o_n___c_a_l_l_b_a_c_k_s_html_a114e6c4d63d6b020e01f526a975d6849"><div class="ttname"><a href="struct_d3_d12_m_a_1_1_a_l_l_o_c_a_t_i_o_n___c_a_l_l_b_a_c_k_s.html#a114e6c4d63d6b020e01f526a975d6849">D3D12MA::ALLOCATION_CALLBACKS::pFree</a></div><div class="ttdeci">FREE_FUNC_PTR pFree</div><div class="ttdoc">Dellocation function.</div><div class="ttdef"><b>Definition:</b> D3D12MemAlloc.h:188</div></div>
<div class="ttc" id="astruct_d3_d12_m_a_1_1_a_l_l_o_c_a_t_i_o_n___c_a_l_l_b_a_c_k_s_html_af4d6436455728696fefd503869226436"><div class="ttname"><a href="struct_d3_d12_m_a_1_1_a_l_l_o_c_a_t_i_o_n___c_a_l_l_b_a_c_k_s.html#af4d6436455728696fefd503869226436">D3D12MA::ALLOCATION_CALLBACKS::pAllocate</a></div><div class="ttdeci">ALLOCATE_FUNC_PTR pAllocate</div><div class="ttdoc">Allocation function.</div><div class="ttdef"><b>Definition:</b> D3D12MemAlloc.h:186</div></div>
<div class="ttc" id="astruct_d3_d12_m_a_1_1_a_l_l_o_c_a_t_o_r___d_e_s_c_html"><div class="ttname"><a href="struct_d3_d12_m_a_1_1_a_l_l_o_c_a_t_o_r___d_e_s_c.html">D3D12MA::ALLOCATOR_DESC</a></div><div class="ttdoc">Parameters of created Allocator object. To be used with CreateAllocator().</div><div class="ttdef"><b>Definition:</b> D3D12MemAlloc.h:750</div></div>
<div class="ttc" id="astruct_d3_d12_m_a_1_1_a_l_l_o_c_a_t_o_r___d_e_s_c_html_a773ecc1945eb47c20e06455c3759e4ef"><div class="ttname"><a href="struct_d3_d12_m_a_1_1_a_l_l_o_c_a_t_o_r___d_e_s_c.html#a773ecc1945eb47c20e06455c3759e4ef">D3D12MA::ALLOCATOR_DESC::pAllocationCallbacks</a></div><div class="ttdeci">const ALLOCATION_CALLBACKS * pAllocationCallbacks</div><div class="ttdoc">Custom CPU memory allocation callbacks. Optional.</div><div class="ttdef"><b>Definition:</b> D3D12MemAlloc.h:770</div></div>
<div class="ttc" id="astruct_d3_d12_m_a_1_1_a_l_l_o_c_a_t_o_r___d_e_s_c_html_abf9a9f87f0ffea52816efd363c5fcd7b"><div class="ttname"><a href="struct_d3_d12_m_a_1_1_a_l_l_o_c_a_t_o_r___d_e_s_c.html#abf9a9f87f0ffea52816efd363c5fcd7b">D3D12MA::ALLOCATOR_DESC::pAdapter</a></div><div class="ttdeci">IDXGIAdapter * pAdapter</div><div class="ttdef"><b>Definition:</b> D3D12MemAlloc.h:776</div></div>
<div class="ttc" id="astruct_d3_d12_m_a_1_1_a_l_l_o_c_a_t_o_r___d_e_s_c_html_ada1bf21205065b3aa0284b5a9ee1cb3c"><div class="ttname"><a href="struct_d3_d12_m_a_1_1_a_l_l_o_c_a_t_o_r___d_e_s_c.html#ada1bf21205065b3aa0284b5a9ee1cb3c">D3D12MA::ALLOCATOR_DESC::pDevice</a></div><div class="ttdeci">ID3D12Device * pDevice</div><div class="ttdef"><b>Definition:</b> D3D12MemAlloc.h:758</div></div>
<div class="ttc" id="astruct_d3_d12_m_a_1_1_a_l_l_o_c_a_t_i_o_n___c_a_l_l_b_a_c_k_s_html"><div class="ttname"><a href="struct_d3_d12_m_a_1_1_a_l_l_o_c_a_t_i_o_n___c_a_l_l_b_a_c_k_s.html">D3D12MA::ALLOCATION_CALLBACKS</a></div><div class="ttdoc">Custom callbacks to CPU memory allocation functions.</div><div class="ttdef"><b>Definition:</b> D3D12MemAlloc.h:185</div></div>
<div class="ttc" id="astruct_d3_d12_m_a_1_1_a_l_l_o_c_a_t_i_o_n___c_a_l_l_b_a_c_k_s_html_a114e6c4d63d6b020e01f526a975d6849"><div class="ttname"><a href="struct_d3_d12_m_a_1_1_a_l_l_o_c_a_t_i_o_n___c_a_l_l_b_a_c_k_s.html#a114e6c4d63d6b020e01f526a975d6849">D3D12MA::ALLOCATION_CALLBACKS::pFree</a></div><div class="ttdeci">FREE_FUNC_PTR pFree</div><div class="ttdoc">Dellocation function.</div><div class="ttdef"><b>Definition:</b> D3D12MemAlloc.h:189</div></div>
<div class="ttc" id="astruct_d3_d12_m_a_1_1_a_l_l_o_c_a_t_i_o_n___c_a_l_l_b_a_c_k_s_html_af4d6436455728696fefd503869226436"><div class="ttname"><a href="struct_d3_d12_m_a_1_1_a_l_l_o_c_a_t_i_o_n___c_a_l_l_b_a_c_k_s.html#af4d6436455728696fefd503869226436">D3D12MA::ALLOCATION_CALLBACKS::pAllocate</a></div><div class="ttdeci">ALLOCATE_FUNC_PTR pAllocate</div><div class="ttdoc">Allocation function.</div><div class="ttdef"><b>Definition:</b> D3D12MemAlloc.h:187</div></div>
<div class="ttc" id="astruct_d3_d12_m_a_1_1_a_l_l_o_c_a_t_o_r___d_e_s_c_html"><div class="ttname"><a href="struct_d3_d12_m_a_1_1_a_l_l_o_c_a_t_o_r___d_e_s_c.html">D3D12MA::ALLOCATOR_DESC</a></div><div class="ttdoc">Parameters of created Allocator object. To be used with CreateAllocator().</div><div class="ttdef"><b>Definition:</b> D3D12MemAlloc.h:751</div></div>
<div class="ttc" id="astruct_d3_d12_m_a_1_1_a_l_l_o_c_a_t_o_r___d_e_s_c_html_a773ecc1945eb47c20e06455c3759e4ef"><div class="ttname"><a href="struct_d3_d12_m_a_1_1_a_l_l_o_c_a_t_o_r___d_e_s_c.html#a773ecc1945eb47c20e06455c3759e4ef">D3D12MA::ALLOCATOR_DESC::pAllocationCallbacks</a></div><div class="ttdeci">const ALLOCATION_CALLBACKS * pAllocationCallbacks</div><div class="ttdoc">Custom CPU memory allocation callbacks. Optional.</div><div class="ttdef"><b>Definition:</b> D3D12MemAlloc.h:771</div></div>
<div class="ttc" id="astruct_d3_d12_m_a_1_1_a_l_l_o_c_a_t_o_r___d_e_s_c_html_abf9a9f87f0ffea52816efd363c5fcd7b"><div class="ttname"><a href="struct_d3_d12_m_a_1_1_a_l_l_o_c_a_t_o_r___d_e_s_c.html#abf9a9f87f0ffea52816efd363c5fcd7b">D3D12MA::ALLOCATOR_DESC::pAdapter</a></div><div class="ttdeci">IDXGIAdapter * pAdapter</div><div class="ttdef"><b>Definition:</b> D3D12MemAlloc.h:777</div></div>
<div class="ttc" id="astruct_d3_d12_m_a_1_1_a_l_l_o_c_a_t_o_r___d_e_s_c_html_ada1bf21205065b3aa0284b5a9ee1cb3c"><div class="ttname"><a href="struct_d3_d12_m_a_1_1_a_l_l_o_c_a_t_o_r___d_e_s_c.html#ada1bf21205065b3aa0284b5a9ee1cb3c">D3D12MA::ALLOCATOR_DESC::pDevice</a></div><div class="ttdeci">ID3D12Device * pDevice</div><div class="ttdef"><b>Definition:</b> D3D12MemAlloc.h:759</div></div>
</div><!-- fragment --><h1><a class="anchor" id="debug_margins"></a>
Debug margins</h1>
<p >By default, allocations are laid out in memory blocks next to each other if possible (considering required alignment returned by <code>ID3D12Device::GetResourceAllocationInfo</code>).</p>

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@ -94,7 +94,7 @@ Features and benefits</h1>
<p >While it is recommended to use default pools whenever possible for simplicity and to give the allocator more opportunities for internal optimizations, custom pools may be useful in following cases:</p>
<ul>
<li>To keep some resources separate from others in memory.</li>
<li>To keep track of memory usage of just a specific group of resources. Statistics can be queried using D3D12MA::Pool::CalculateStats.</li>
<li>To keep track of memory usage of just a specific group of resources. Statistics can be queried using <a class="el" href="class_d3_d12_m_a_1_1_pool.html#ad07999ac5dc8f0c63187afd45d551910" title="Retrieves detailed statistics of the custom pool that are slower to calculate.">D3D12MA::Pool::CalculateStatistics</a>.</li>
<li>To use specific size of a memory block (<code>ID3D12Heap</code>). To set it, use member <a class="el" href="struct_d3_d12_m_a_1_1_p_o_o_l___d_e_s_c.html#af7284cc51a8ed5b551075584256de23c" title="Size of a single heap (memory block) to be allocated as part of this pool, in bytes....">D3D12MA::POOL_DESC::BlockSize</a>. When set to 0, the library uses automatically determined, variable block sizes.</li>
<li>To reserve some minimum amount of memory allocated. To use it, set member <a class="el" href="struct_d3_d12_m_a_1_1_p_o_o_l___d_e_s_c.html#a6f10db3911a3bea1becfc9a0dfa5bac8" title="Minimum number of heaps (memory blocks) to be always allocated in this pool, even if they stay empty....">D3D12MA::POOL_DESC::MinBlockCount</a>.</li>
<li>To limit maximum amount of memory allocated. To use it, set member <a class="el" href="struct_d3_d12_m_a_1_1_p_o_o_l___d_e_s_c.html#abbce3a99f253928f9c3c09fa16015f9e" title="Maximum number of heaps (memory blocks) that can be allocated in this pool. Optional.">D3D12MA::POOL_DESC::MaxBlockCount</a>.</li>
@ -110,7 +110,7 @@ Features and benefits</h1>
<div class="line">ID3D12Resource* res;</div>
<div class="line">hr = allocator-&gt;CreateResource(&amp;allocDesc, &amp;resDesc,</div>
<div class="line"> D3D12_RESOURCE_STATE_GENERIC_READ, NULL, &amp;alloc, IID_PPV_ARGS(&amp;res));</div>
<div class="ttc" id="anamespace_d3_d12_m_a_html_abbad31a7e0b3d09d77f3fb704b77645ea661a5472dba3dcecc5a2cc92afd25675"><div class="ttname"><a href="namespace_d3_d12_m_a.html#abbad31a7e0b3d09d77f3fb704b77645ea661a5472dba3dcecc5a2cc92afd25675">D3D12MA::ALLOCATION_FLAG_COMMITTED</a></div><div class="ttdeci">@ ALLOCATION_FLAG_COMMITTED</div><div class="ttdef"><b>Definition:</b> D3D12MemAlloc.h:210</div></div>
<div class="ttc" id="anamespace_d3_d12_m_a_html_abbad31a7e0b3d09d77f3fb704b77645ea661a5472dba3dcecc5a2cc92afd25675"><div class="ttname"><a href="namespace_d3_d12_m_a.html#abbad31a7e0b3d09d77f3fb704b77645ea661a5472dba3dcecc5a2cc92afd25675">D3D12MA::ALLOCATION_FLAG_COMMITTED</a></div><div class="ttdeci">@ ALLOCATION_FLAG_COMMITTED</div><div class="ttdef"><b>Definition:</b> D3D12MemAlloc.h:211</div></div>
</div><!-- fragment --><p >This feature may seem unnecessary, but creating committed allocations from custom pools may be useful in some cases, e.g. to have separate memory usage statistics for some group of resources or to use extended allocation parameters, like custom <code>D3D12_HEAP_PROPERTIES</code>, which are available only in custom pools. </p>
</div></div><!-- contents -->
</div><!-- PageDoc -->

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@ -77,6 +77,16 @@ Thread safety</h1>
<li>When the allocator is created with <a class="el" href="namespace_d3_d12_m_a.html#ad5ae5a5e42b878f2e18ab5d1fbfb9916a1b06bb21df006f76a9ed1bc41838bc52">D3D12MA::ALLOCATOR_FLAG_SINGLETHREADED</a>, calls to methods of <a class="el" href="class_d3_d12_m_a_1_1_allocator.html" title="Represents main object of this library initialized for particular ID3D12Device.">D3D12MA::Allocator</a> class must be made from a single thread or synchronized by the user. Using this flag may improve performance.</li>
<li><a class="el" href="class_d3_d12_m_a_1_1_virtual_block.html" title="Represents pure allocation algorithm and a data structure with allocations in some memory block,...">D3D12MA::VirtualBlock</a> is not safe to be used from multiple threads simultaneously.</li>
</ul>
<h1><a class="anchor" id="general_considerations_versioning_and_compatibility"></a>
Versioning and compatibility</h1>
<p >The library uses <a href="https://semver.org/"><b>Semantic Versioning</b></a>, which means version numbers follow convention: Major.Minor.Patch (e.g. 2.3.0), where:</p>
<ul>
<li>Incremented Patch version means a release is backward- and forward-compatible, introducing only some internal improvements, bug fixes, optimizations etc. or changes that are out of scope of the official API described in this documentation.</li>
<li>Incremented Minor version means a release is backward-compatible, so existing code that uses the library should continue to work, while some new symbols could have been added: new structures, functions, new values in existing enums and bit flags, new structure members, but not new function parameters.</li>
<li>Incrementing Major version means a release could break some backward compatibility.</li>
</ul>
<p >All changes between official releases are documented in file "CHANGELOG.md".</p>
<dl class="section warning"><dt>Warning</dt><dd>Backward compatiblity is considered on the level of C++ source code, not binary linkage. Adding new members to existing structures is treated as backward compatible if initializing the new members to binary zero results in the old behavior. You should always fully initialize all library structures to zeros and not rely on their exact binary size.</dd></dl>
<h1><a class="anchor" id="general_considerations_features_not_supported"></a>
Features not supported</h1>
<p >Features deliberately excluded from the scope of this library:</p>

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@ -90,6 +90,7 @@ Table of contents</h1>
</li>
<li><a class="el" href="general_considerations.html">General considerations</a><ul>
<li><a class="el" href="general_considerations.html#general_considerations_thread_safety">Thread safety</a></li>
<li><a class="el" href="general_considerations.html#general_considerations_versioning_and_compatibility">Versioning and compatibility</a></li>
<li><a class="el" href="general_considerations.html#general_considerations_features_not_supported">Features not supported</a></li>
</ul>
</li>

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@ -90,11 +90,11 @@ Project setup and initialization</h1>
<div class="line"> </div>
<div class="line"><a class="code hl_class" href="class_d3_d12_m_a_1_1_allocator.html">D3D12MA::Allocator</a>* allocator;</div>
<div class="line">HRESULT hr = <a class="code hl_function" href="namespace_d3_d12_m_a.html#ab7a1cd1683986d75ce1488b0920f4cb0">D3D12MA::CreateAllocator</a>(&amp;allocatorDesc, &amp;allocator);</div>
<div class="ttc" id="aclass_d3_d12_m_a_1_1_allocator_html"><div class="ttname"><a href="class_d3_d12_m_a_1_1_allocator.html">D3D12MA::Allocator</a></div><div class="ttdoc">Represents main object of this library initialized for particular ID3D12Device.</div><div class="ttdef"><b>Definition:</b> D3D12MemAlloc.h:789</div></div>
<div class="ttc" id="aclass_d3_d12_m_a_1_1_allocator_html"><div class="ttname"><a href="class_d3_d12_m_a_1_1_allocator.html">D3D12MA::Allocator</a></div><div class="ttdoc">Represents main object of this library initialized for particular ID3D12Device.</div><div class="ttdef"><b>Definition:</b> D3D12MemAlloc.h:790</div></div>
<div class="ttc" id="anamespace_d3_d12_m_a_html_ab7a1cd1683986d75ce1488b0920f4cb0"><div class="ttname"><a href="namespace_d3_d12_m_a.html#ab7a1cd1683986d75ce1488b0920f4cb0">D3D12MA::CreateAllocator</a></div><div class="ttdeci">D3D12MA_API HRESULT CreateAllocator(const ALLOCATOR_DESC *pDesc, Allocator **ppAllocator)</div><div class="ttdoc">Creates new main D3D12MA::Allocator object and returns it through ppAllocator.</div></div>
<div class="ttc" id="astruct_d3_d12_m_a_1_1_a_l_l_o_c_a_t_o_r___d_e_s_c_html"><div class="ttname"><a href="struct_d3_d12_m_a_1_1_a_l_l_o_c_a_t_o_r___d_e_s_c.html">D3D12MA::ALLOCATOR_DESC</a></div><div class="ttdoc">Parameters of created Allocator object. To be used with CreateAllocator().</div><div class="ttdef"><b>Definition:</b> D3D12MemAlloc.h:750</div></div>
<div class="ttc" id="astruct_d3_d12_m_a_1_1_a_l_l_o_c_a_t_o_r___d_e_s_c_html_abf9a9f87f0ffea52816efd363c5fcd7b"><div class="ttname"><a href="struct_d3_d12_m_a_1_1_a_l_l_o_c_a_t_o_r___d_e_s_c.html#abf9a9f87f0ffea52816efd363c5fcd7b">D3D12MA::ALLOCATOR_DESC::pAdapter</a></div><div class="ttdeci">IDXGIAdapter * pAdapter</div><div class="ttdef"><b>Definition:</b> D3D12MemAlloc.h:776</div></div>
<div class="ttc" id="astruct_d3_d12_m_a_1_1_a_l_l_o_c_a_t_o_r___d_e_s_c_html_ada1bf21205065b3aa0284b5a9ee1cb3c"><div class="ttname"><a href="struct_d3_d12_m_a_1_1_a_l_l_o_c_a_t_o_r___d_e_s_c.html#ada1bf21205065b3aa0284b5a9ee1cb3c">D3D12MA::ALLOCATOR_DESC::pDevice</a></div><div class="ttdeci">ID3D12Device * pDevice</div><div class="ttdef"><b>Definition:</b> D3D12MemAlloc.h:758</div></div>
<div class="ttc" id="astruct_d3_d12_m_a_1_1_a_l_l_o_c_a_t_o_r___d_e_s_c_html"><div class="ttname"><a href="struct_d3_d12_m_a_1_1_a_l_l_o_c_a_t_o_r___d_e_s_c.html">D3D12MA::ALLOCATOR_DESC</a></div><div class="ttdoc">Parameters of created Allocator object. To be used with CreateAllocator().</div><div class="ttdef"><b>Definition:</b> D3D12MemAlloc.h:751</div></div>
<div class="ttc" id="astruct_d3_d12_m_a_1_1_a_l_l_o_c_a_t_o_r___d_e_s_c_html_abf9a9f87f0ffea52816efd363c5fcd7b"><div class="ttname"><a href="struct_d3_d12_m_a_1_1_a_l_l_o_c_a_t_o_r___d_e_s_c.html#abf9a9f87f0ffea52816efd363c5fcd7b">D3D12MA::ALLOCATOR_DESC::pAdapter</a></div><div class="ttdeci">IDXGIAdapter * pAdapter</div><div class="ttdef"><b>Definition:</b> D3D12MemAlloc.h:777</div></div>
<div class="ttc" id="astruct_d3_d12_m_a_1_1_a_l_l_o_c_a_t_o_r___d_e_s_c_html_ada1bf21205065b3aa0284b5a9ee1cb3c"><div class="ttname"><a href="struct_d3_d12_m_a_1_1_a_l_l_o_c_a_t_o_r___d_e_s_c.html#ada1bf21205065b3aa0284b5a9ee1cb3c">D3D12MA::ALLOCATOR_DESC::pDevice</a></div><div class="ttdeci">ID3D12Device * pDevice</div><div class="ttdef"><b>Definition:</b> D3D12MemAlloc.h:759</div></div>
</div><!-- fragment --><p >(5.) Right before destroying the D3D12 device, destroy the allocator object.</p>
<p >Objects of this library must be destroyed by calling <code>Release</code> method. They are somewhat compatible with COM: they implement <code>IUnknown</code> interface with its virtual methods: <code>AddRef</code>, <code>Release</code>, <code>QueryInterface</code>, and they are reference-counted internally. You can use smart pointers designed for COM with objects of this library - e.g. <code>CComPtr</code> or <code>Microsoft::WRL::ComPtr</code>. The reference counter is thread-safe. <code>QueryInterface</code> method supports only <code>IUnknown</code>, as classes of this library don't define their own GUIDs.</p>
<div class="fragment"><div class="line">allocator-&gt;Release();</div>
@ -117,7 +117,7 @@ Creating resources</h1>
<div class="line">resourceDesc.Flags = D3D12_RESOURCE_FLAG_NONE;</div>
<div class="line"> </div>
<div class="line"><a class="code hl_struct" href="struct_d3_d12_m_a_1_1_a_l_l_o_c_a_t_i_o_n___d_e_s_c.html">D3D12MA::ALLOCATION_DESC</a> allocationDesc = {};</div>
<div class="line">allocDesc.<a class="code hl_variable" href="struct_d3_d12_m_a_1_1_a_l_l_o_c_a_t_i_o_n___d_e_s_c.html#aa46b3c0456e5a23edef3328607ebf4d7">HeapType</a> = D3D12_HEAP_TYPE_DEFAULT;</div>
<div class="line">allocationDesc.<a class="code hl_variable" href="struct_d3_d12_m_a_1_1_a_l_l_o_c_a_t_i_o_n___d_e_s_c.html#aa46b3c0456e5a23edef3328607ebf4d7">HeapType</a> = D3D12_HEAP_TYPE_DEFAULT;</div>
<div class="line"> </div>
<div class="line">D3D12Resource* resource;</div>
<div class="line"><a class="code hl_class" href="class_d3_d12_m_a_1_1_allocation.html">D3D12MA::Allocation</a>* allocation;</div>
@ -128,10 +128,10 @@ Creating resources</h1>
<div class="line"> NULL,</div>
<div class="line"> &amp;allocation,</div>
<div class="line"> IID_PPV_ARGS(&amp;resource));</div>
<div class="ttc" id="aclass_d3_d12_m_a_1_1_allocation_html"><div class="ttname"><a href="class_d3_d12_m_a_1_1_allocation.html">D3D12MA::Allocation</a></div><div class="ttdoc">Represents single memory allocation.</div><div class="ttdef"><b>Definition:</b> D3D12MemAlloc.h:420</div></div>
<div class="ttc" id="aclass_d3_d12_m_a_1_1_allocation_html"><div class="ttname"><a href="class_d3_d12_m_a_1_1_allocation.html">D3D12MA::Allocation</a></div><div class="ttdoc">Represents single memory allocation.</div><div class="ttdef"><b>Definition:</b> D3D12MemAlloc.h:421</div></div>
<div class="ttc" id="aclass_d3_d12_m_a_1_1_allocator_html_aa37d6b9fe8ea0864f7a35b9d68e8345a"><div class="ttname"><a href="class_d3_d12_m_a_1_1_allocator.html#aa37d6b9fe8ea0864f7a35b9d68e8345a">D3D12MA::Allocator::CreateResource</a></div><div class="ttdeci">HRESULT CreateResource(const ALLOCATION_DESC *pAllocDesc, const D3D12_RESOURCE_DESC *pResourceDesc, D3D12_RESOURCE_STATES InitialResourceState, const D3D12_CLEAR_VALUE *pOptimizedClearValue, Allocation **ppAllocation, REFIID riidResource, void **ppvResource)</div><div class="ttdoc">Allocates memory and creates a D3D12 resource (buffer or texture). This is the main allocation functi...</div></div>
<div class="ttc" id="astruct_d3_d12_m_a_1_1_a_l_l_o_c_a_t_i_o_n___d_e_s_c_html"><div class="ttname"><a href="struct_d3_d12_m_a_1_1_a_l_l_o_c_a_t_i_o_n___d_e_s_c.html">D3D12MA::ALLOCATION_DESC</a></div><div class="ttdoc">Parameters of created D3D12MA::Allocation object. To be used with Allocator::CreateResource.</div><div class="ttdef"><b>Definition:</b> D3D12MemAlloc.h:239</div></div>
<div class="ttc" id="astruct_d3_d12_m_a_1_1_a_l_l_o_c_a_t_i_o_n___d_e_s_c_html_aa46b3c0456e5a23edef3328607ebf4d7"><div class="ttname"><a href="struct_d3_d12_m_a_1_1_a_l_l_o_c_a_t_i_o_n___d_e_s_c.html#aa46b3c0456e5a23edef3328607ebf4d7">D3D12MA::ALLOCATION_DESC::HeapType</a></div><div class="ttdeci">D3D12_HEAP_TYPE HeapType</div><div class="ttdoc">The type of memory heap where the new allocation should be placed.</div><div class="ttdef"><b>Definition:</b> D3D12MemAlloc.h:248</div></div>
<div class="ttc" id="astruct_d3_d12_m_a_1_1_a_l_l_o_c_a_t_i_o_n___d_e_s_c_html"><div class="ttname"><a href="struct_d3_d12_m_a_1_1_a_l_l_o_c_a_t_i_o_n___d_e_s_c.html">D3D12MA::ALLOCATION_DESC</a></div><div class="ttdoc">Parameters of created D3D12MA::Allocation object. To be used with Allocator::CreateResource.</div><div class="ttdef"><b>Definition:</b> D3D12MemAlloc.h:240</div></div>
<div class="ttc" id="astruct_d3_d12_m_a_1_1_a_l_l_o_c_a_t_i_o_n___d_e_s_c_html_aa46b3c0456e5a23edef3328607ebf4d7"><div class="ttname"><a href="struct_d3_d12_m_a_1_1_a_l_l_o_c_a_t_i_o_n___d_e_s_c.html#aa46b3c0456e5a23edef3328607ebf4d7">D3D12MA::ALLOCATION_DESC::HeapType</a></div><div class="ttdeci">D3D12_HEAP_TYPE HeapType</div><div class="ttdoc">The type of memory heap where the new allocation should be placed.</div><div class="ttdef"><b>Definition:</b> D3D12MemAlloc.h:249</div></div>
</div><!-- fragment --><p >You need to remember both resource and allocation objects and destroy them separately when no longer needed.</p>
<div class="fragment"><div class="line">allocation-&gt;Release();</div>
<div class="line">resource-&gt;Release();</div>
@ -140,8 +140,8 @@ Creating resources</h1>
<p >The library also automatically handles resource heap tier. When <code>D3D12_FEATURE_DATA_D3D12_OPTIONS::ResourceHeapTier</code> equals <code>D3D12_RESOURCE_HEAP_TIER_1</code>, resources of 3 types: buffers, textures that are render targets or depth-stencil, and other textures must be kept in separate heaps. When <code>D3D12_RESOURCE_HEAP_TIER_2</code>, they can be kept together. By using this library, you don't need to handle this manually.</p>
<h1><a class="anchor" id="quick_start_mapping_memory"></a>
Mapping memory</h1>
<p >The process of getting regular CPU-side pointer to the memory of a resource in Direct3D is called "mapping". There are rules and restrictions to this process, as described in D3D12 documentation of ID3D12Resource::Map method.</p>
<p >Mapping happens on the level of particular resources, not entire memory heaps, and so it is out of scope of this library. Just as the linked documentation says:</p>
<p >The process of getting regular CPU-side pointer to the memory of a resource in Direct3D is called "mapping". There are rules and restrictions to this process, as described in D3D12 documentation of <code>ID3D12Resource::Map</code> method.</p>
<p >Mapping happens on the level of particular resources, not entire memory heaps, and so it is out of scope of this library. Just as the documentation of the <code>Map</code> function says:</p>
<ul>
<li>Returned pointer refers to data of particular subresource, not entire memory heap.</li>
<li>You can map same resource multiple times. It is ref-counted internally.</li>

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@ -144,11 +144,11 @@ $(function() {
<div class="line">res2-&gt;Release();</div>
<div class="line">res1-&gt;Release();</div>
<div class="line">alloc-&gt;Release();</div>
<div class="ttc" id="aclass_d3_d12_m_a_1_1_allocation_html"><div class="ttname"><a href="class_d3_d12_m_a_1_1_allocation.html">D3D12MA::Allocation</a></div><div class="ttdoc">Represents single memory allocation.</div><div class="ttdef"><b>Definition:</b> D3D12MemAlloc.h:420</div></div>
<div class="ttc" id="aclass_d3_d12_m_a_1_1_allocation_html"><div class="ttname"><a href="class_d3_d12_m_a_1_1_allocation.html">D3D12MA::Allocation</a></div><div class="ttdoc">Represents single memory allocation.</div><div class="ttdef"><b>Definition:</b> D3D12MemAlloc.h:421</div></div>
<div class="ttc" id="aclass_d3_d12_m_a_1_1_allocation_html_adca8d5a82bed492fe7265fcda6e53da2"><div class="ttname"><a href="class_d3_d12_m_a_1_1_allocation.html#adca8d5a82bed492fe7265fcda6e53da2">D3D12MA::Allocation::GetHeap</a></div><div class="ttdeci">ID3D12Heap * GetHeap() const</div><div class="ttdoc">Returns memory heap that the resource is created in.</div></div>
<div class="ttc" id="astruct_d3_d12_m_a_1_1_a_l_l_o_c_a_t_i_o_n___d_e_s_c_html"><div class="ttname"><a href="struct_d3_d12_m_a_1_1_a_l_l_o_c_a_t_i_o_n___d_e_s_c.html">D3D12MA::ALLOCATION_DESC</a></div><div class="ttdoc">Parameters of created D3D12MA::Allocation object. To be used with Allocator::CreateResource.</div><div class="ttdef"><b>Definition:</b> D3D12MemAlloc.h:239</div></div>
<div class="ttc" id="astruct_d3_d12_m_a_1_1_a_l_l_o_c_a_t_i_o_n___d_e_s_c_html_a97878838f976b2d1e6b1a76881035690"><div class="ttname"><a href="struct_d3_d12_m_a_1_1_a_l_l_o_c_a_t_i_o_n___d_e_s_c.html#a97878838f976b2d1e6b1a76881035690">D3D12MA::ALLOCATION_DESC::ExtraHeapFlags</a></div><div class="ttdeci">D3D12_HEAP_FLAGS ExtraHeapFlags</div><div class="ttdoc">Additional heap flags to be used when allocating memory.</div><div class="ttdef"><b>Definition:</b> D3D12MemAlloc.h:264</div></div>
<div class="ttc" id="astruct_d3_d12_m_a_1_1_a_l_l_o_c_a_t_i_o_n___d_e_s_c_html_aa46b3c0456e5a23edef3328607ebf4d7"><div class="ttname"><a href="struct_d3_d12_m_a_1_1_a_l_l_o_c_a_t_i_o_n___d_e_s_c.html#aa46b3c0456e5a23edef3328607ebf4d7">D3D12MA::ALLOCATION_DESC::HeapType</a></div><div class="ttdeci">D3D12_HEAP_TYPE HeapType</div><div class="ttdoc">The type of memory heap where the new allocation should be placed.</div><div class="ttdef"><b>Definition:</b> D3D12MemAlloc.h:248</div></div>
<div class="ttc" id="astruct_d3_d12_m_a_1_1_a_l_l_o_c_a_t_i_o_n___d_e_s_c_html"><div class="ttname"><a href="struct_d3_d12_m_a_1_1_a_l_l_o_c_a_t_i_o_n___d_e_s_c.html">D3D12MA::ALLOCATION_DESC</a></div><div class="ttdoc">Parameters of created D3D12MA::Allocation object. To be used with Allocator::CreateResource.</div><div class="ttdef"><b>Definition:</b> D3D12MemAlloc.h:240</div></div>
<div class="ttc" id="astruct_d3_d12_m_a_1_1_a_l_l_o_c_a_t_i_o_n___d_e_s_c_html_a97878838f976b2d1e6b1a76881035690"><div class="ttname"><a href="struct_d3_d12_m_a_1_1_a_l_l_o_c_a_t_i_o_n___d_e_s_c.html#a97878838f976b2d1e6b1a76881035690">D3D12MA::ALLOCATION_DESC::ExtraHeapFlags</a></div><div class="ttdeci">D3D12_HEAP_FLAGS ExtraHeapFlags</div><div class="ttdoc">Additional heap flags to be used when allocating memory.</div><div class="ttdef"><b>Definition:</b> D3D12MemAlloc.h:265</div></div>
<div class="ttc" id="astruct_d3_d12_m_a_1_1_a_l_l_o_c_a_t_i_o_n___d_e_s_c_html_aa46b3c0456e5a23edef3328607ebf4d7"><div class="ttname"><a href="struct_d3_d12_m_a_1_1_a_l_l_o_c_a_t_i_o_n___d_e_s_c.html#aa46b3c0456e5a23edef3328607ebf4d7">D3D12MA::ALLOCATION_DESC::HeapType</a></div><div class="ttdeci">D3D12_HEAP_TYPE HeapType</div><div class="ttdoc">The type of memory heap where the new allocation should be placed.</div><div class="ttdef"><b>Definition:</b> D3D12MemAlloc.h:249</div></div>
</div><!-- fragment --><p >Remember that using resouces that alias in memory requires proper synchronization. You need to issue a special barrier of type <code>D3D12_RESOURCE_BARRIER_TYPE_ALIASING</code>. You also need to treat a resource after aliasing as uninitialized - containing garbage data. For example, if you use <code>res1</code> and then want to use <code>res2</code>, you need to first initialize <code>res2</code> using either Clear, Discard, or Copy to the entire resource.</p>
<p >Additional considerations:</p>
<ul>

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@ -85,9 +85,9 @@ Numeric statistics</h1>
<div class="line">printf(<span class="stringliteral">&quot;D3D12 reports total usage %llu B with budget %llu B.\n&quot;</span>,</div>
<div class="line"> localBudget.<a class="code hl_variable" href="struct_d3_d12_m_a_1_1_budget.html#a77a8c9e32d6602f95b7d1c285cddd253">UsageBytes</a>,</div>
<div class="line"> localBudget.<a class="code hl_variable" href="struct_d3_d12_m_a_1_1_budget.html#a326515f08d89ee2e31dcfdd5c1e8ac71">BudgetBytes</a>);</div>
<div class="ttc" id="astruct_d3_d12_m_a_1_1_budget_html"><div class="ttname"><a href="struct_d3_d12_m_a_1_1_budget.html">D3D12MA::Budget</a></div><div class="ttdoc">Statistics of current memory usage and available budget for a specific memory segment group.</div><div class="ttdef"><b>Definition:</b> D3D12MemAlloc.h:372</div></div>
<div class="ttc" id="astruct_d3_d12_m_a_1_1_budget_html_a326515f08d89ee2e31dcfdd5c1e8ac71"><div class="ttname"><a href="struct_d3_d12_m_a_1_1_budget.html#a326515f08d89ee2e31dcfdd5c1e8ac71">D3D12MA::Budget::BudgetBytes</a></div><div class="ttdeci">UINT64 BudgetBytes</div><div class="ttdoc">Estimated amount of memory available to the program.</div><div class="ttdef"><b>Definition:</b> D3D12MemAlloc.h:395</div></div>
<div class="ttc" id="astruct_d3_d12_m_a_1_1_budget_html_a77a8c9e32d6602f95b7d1c285cddd253"><div class="ttname"><a href="struct_d3_d12_m_a_1_1_budget.html#a77a8c9e32d6602f95b7d1c285cddd253">D3D12MA::Budget::UsageBytes</a></div><div class="ttdeci">UINT64 UsageBytes</div><div class="ttdoc">Estimated current memory usage of the program.</div><div class="ttdef"><b>Definition:</b> D3D12MemAlloc.h:384</div></div>
<div class="ttc" id="astruct_d3_d12_m_a_1_1_budget_html"><div class="ttname"><a href="struct_d3_d12_m_a_1_1_budget.html">D3D12MA::Budget</a></div><div class="ttdoc">Statistics of current memory usage and available budget for a specific memory segment group.</div><div class="ttdef"><b>Definition:</b> D3D12MemAlloc.h:373</div></div>
<div class="ttc" id="astruct_d3_d12_m_a_1_1_budget_html_a326515f08d89ee2e31dcfdd5c1e8ac71"><div class="ttname"><a href="struct_d3_d12_m_a_1_1_budget.html#a326515f08d89ee2e31dcfdd5c1e8ac71">D3D12MA::Budget::BudgetBytes</a></div><div class="ttdeci">UINT64 BudgetBytes</div><div class="ttdoc">Estimated amount of memory available to the program.</div><div class="ttdef"><b>Definition:</b> D3D12MemAlloc.h:396</div></div>
<div class="ttc" id="astruct_d3_d12_m_a_1_1_budget_html_a77a8c9e32d6602f95b7d1c285cddd253"><div class="ttname"><a href="struct_d3_d12_m_a_1_1_budget.html#a77a8c9e32d6602f95b7d1c285cddd253">D3D12MA::Budget::UsageBytes</a></div><div class="ttdeci">UINT64 UsageBytes</div><div class="ttdoc">Estimated current memory usage of the program.</div><div class="ttdef"><b>Definition:</b> D3D12MemAlloc.h:385</div></div>
</div><!-- fragment --><p >You can query for more detailed statistics per heap type, memory segment group, and totals, including minimum and maximum allocation size and unused range size, by calling function <a class="el" href="class_d3_d12_m_a_1_1_allocator.html#a99db00df909963573a976c203b107d22" title="Retrieves statistics from current state of the allocator.">D3D12MA::Allocator::CalculateStatistics()</a> and inspecting structure <a class="el" href="struct_d3_d12_m_a_1_1_total_statistics.html" title="General statistics from current state of the allocator - total memory usage across all memory heaps a...">D3D12MA::TotalStatistics</a>. This function is slower though, as it has to traverse all the internal data structures, so it should be used only for debugging purposes.</p>
<p >You can query for statistics of a custom pool using function <a class="el" href="class_d3_d12_m_a_1_1_pool.html#aa9d849dc4667314b2a53eddf02f5af91" title="Retrieves basic statistics of the custom pool that are fast to calculate.">D3D12MA::Pool::GetStatistics()</a> or <a class="el" href="class_d3_d12_m_a_1_1_pool.html#ad07999ac5dc8f0c63187afd45d551910" title="Retrieves detailed statistics of the custom pool that are slower to calculate.">D3D12MA::Pool::CalculateStatistics()</a>.</p>
<p >You can query for information about a specific allocation using functions of the <a class="el" href="class_d3_d12_m_a_1_1_allocation.html" title="Represents single memory allocation.">D3D12MA::Allocation</a> class, e.g. <code>GetSize()</code>, <code>GetOffset()</code>, <code>GetHeap()</code>.</p>

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@ -83,10 +83,10 @@ Creating virtual block</h1>
<div class="line"> </div>
<div class="line"><a class="code hl_class" href="class_d3_d12_m_a_1_1_virtual_block.html">D3D12MA::VirtualBlock</a> *block;</div>
<div class="line">HRESULT hr = <a class="code hl_function" href="namespace_d3_d12_m_a.html#ab024647ae85ee63e2fa2c1c4beac6d98">CreateVirtualBlock</a>(&amp;blockDesc, &amp;block);</div>
<div class="ttc" id="aclass_d3_d12_m_a_1_1_virtual_block_html"><div class="ttname"><a href="class_d3_d12_m_a_1_1_virtual_block.html">D3D12MA::VirtualBlock</a></div><div class="ttdoc">Represents pure allocation algorithm and a data structure with allocations in some memory block,...</div><div class="ttdef"><b>Definition:</b> D3D12MemAlloc.h:1113</div></div>
<div class="ttc" id="aclass_d3_d12_m_a_1_1_virtual_block_html"><div class="ttname"><a href="class_d3_d12_m_a_1_1_virtual_block.html">D3D12MA::VirtualBlock</a></div><div class="ttdoc">Represents pure allocation algorithm and a data structure with allocations in some memory block,...</div><div class="ttdef"><b>Definition:</b> D3D12MemAlloc.h:1114</div></div>
<div class="ttc" id="anamespace_d3_d12_m_a_html_ab024647ae85ee63e2fa2c1c4beac6d98"><div class="ttname"><a href="namespace_d3_d12_m_a.html#ab024647ae85ee63e2fa2c1c4beac6d98">D3D12MA::CreateVirtualBlock</a></div><div class="ttdeci">D3D12MA_API HRESULT CreateVirtualBlock(const VIRTUAL_BLOCK_DESC *pDesc, VirtualBlock **ppVirtualBlock)</div><div class="ttdoc">Creates new D3D12MA::VirtualBlock object and returns it through ppVirtualBlock.</div></div>
<div class="ttc" id="astruct_d3_d12_m_a_1_1_v_i_r_t_u_a_l___b_l_o_c_k___d_e_s_c_html"><div class="ttname"><a href="struct_d3_d12_m_a_1_1_v_i_r_t_u_a_l___b_l_o_c_k___d_e_s_c.html">D3D12MA::VIRTUAL_BLOCK_DESC</a></div><div class="ttdoc">Parameters of created D3D12MA::VirtualBlock object to be passed to CreateVirtualBlock().</div><div class="ttdef"><b>Definition:</b> D3D12MemAlloc.h:1033</div></div>
<div class="ttc" id="astruct_d3_d12_m_a_1_1_v_i_r_t_u_a_l___b_l_o_c_k___d_e_s_c_html_ac56491679f276a5a9956ed99bc4654e4"><div class="ttname"><a href="struct_d3_d12_m_a_1_1_v_i_r_t_u_a_l___b_l_o_c_k___d_e_s_c.html#ac56491679f276a5a9956ed99bc4654e4">D3D12MA::VIRTUAL_BLOCK_DESC::Size</a></div><div class="ttdeci">UINT64 Size</div><div class="ttdoc">Total size of the block.</div><div class="ttdef"><b>Definition:</b> D3D12MemAlloc.h:1041</div></div>
<div class="ttc" id="astruct_d3_d12_m_a_1_1_v_i_r_t_u_a_l___b_l_o_c_k___d_e_s_c_html"><div class="ttname"><a href="struct_d3_d12_m_a_1_1_v_i_r_t_u_a_l___b_l_o_c_k___d_e_s_c.html">D3D12MA::VIRTUAL_BLOCK_DESC</a></div><div class="ttdoc">Parameters of created D3D12MA::VirtualBlock object to be passed to CreateVirtualBlock().</div><div class="ttdef"><b>Definition:</b> D3D12MemAlloc.h:1034</div></div>
<div class="ttc" id="astruct_d3_d12_m_a_1_1_v_i_r_t_u_a_l___b_l_o_c_k___d_e_s_c_html_ac56491679f276a5a9956ed99bc4654e4"><div class="ttname"><a href="struct_d3_d12_m_a_1_1_v_i_r_t_u_a_l___b_l_o_c_k___d_e_s_c.html#ac56491679f276a5a9956ed99bc4654e4">D3D12MA::VIRTUAL_BLOCK_DESC::Size</a></div><div class="ttdeci">UINT64 Size</div><div class="ttdoc">Total size of the block.</div><div class="ttdef"><b>Definition:</b> D3D12MemAlloc.h:1042</div></div>
</div><!-- fragment --><h1><a class="anchor" id="virtual_allocator_making_virtual_allocations"></a>
Making virtual allocations</h1>
<p ><a class="el" href="class_d3_d12_m_a_1_1_virtual_block.html" title="Represents pure allocation algorithm and a data structure with allocations in some memory block,...">D3D12MA::VirtualBlock</a> object contains internal data structure that keeps track of free and occupied regions using the same code as the main D3D12 memory allocator. A single allocation is identified by a lightweight structure <a class="el" href="struct_d3_d12_m_a_1_1_virtual_allocation.html" title="Represents single memory allocation done inside VirtualBlock.">D3D12MA::VirtualAllocation</a>. You will also likely want to know the offset at which the allocation was made in the block.</p>
@ -111,9 +111,9 @@ Making virtual allocations</h1>
<div class="line"> <span class="comment">// Allocation failed - no space for it could be found. Handle this error!</span></div>
<div class="line">}</div>
<div class="ttc" id="aclass_d3_d12_m_a_1_1_virtual_block_html_a9281daf76e888ea1bd5247d5732e8179"><div class="ttname"><a href="class_d3_d12_m_a_1_1_virtual_block.html#a9281daf76e888ea1bd5247d5732e8179">D3D12MA::VirtualBlock::Allocate</a></div><div class="ttdeci">HRESULT Allocate(const VIRTUAL_ALLOCATION_DESC *pDesc, VirtualAllocation *pAllocation, UINT64 *pOffset)</div><div class="ttdoc">Creates new allocation.</div></div>
<div class="ttc" id="astruct_d3_d12_m_a_1_1_v_i_r_t_u_a_l___a_l_l_o_c_a_t_i_o_n___d_e_s_c_html"><div class="ttname"><a href="struct_d3_d12_m_a_1_1_v_i_r_t_u_a_l___a_l_l_o_c_a_t_i_o_n___d_e_s_c.html">D3D12MA::VIRTUAL_ALLOCATION_DESC</a></div><div class="ttdoc">Parameters of created virtual allocation to be passed to VirtualBlock::Allocate().</div><div class="ttdef"><b>Definition:</b> D3D12MemAlloc.h:1064</div></div>
<div class="ttc" id="astruct_d3_d12_m_a_1_1_v_i_r_t_u_a_l___a_l_l_o_c_a_t_i_o_n___d_e_s_c_html_a976b649e45abdd0769da0d79acde4bac"><div class="ttname"><a href="struct_d3_d12_m_a_1_1_v_i_r_t_u_a_l___a_l_l_o_c_a_t_i_o_n___d_e_s_c.html#a976b649e45abdd0769da0d79acde4bac">D3D12MA::VIRTUAL_ALLOCATION_DESC::Size</a></div><div class="ttdeci">UINT64 Size</div><div class="ttdoc">Size of the allocation.</div><div class="ttdef"><b>Definition:</b> D3D12MemAlloc.h:1071</div></div>
<div class="ttc" id="astruct_d3_d12_m_a_1_1_virtual_allocation_html"><div class="ttname"><a href="struct_d3_d12_m_a_1_1_virtual_allocation.html">D3D12MA::VirtualAllocation</a></div><div class="ttdoc">Represents single memory allocation done inside VirtualBlock.</div><div class="ttdef"><b>Definition:</b> D3D12MemAlloc.h:400</div></div>
<div class="ttc" id="astruct_d3_d12_m_a_1_1_v_i_r_t_u_a_l___a_l_l_o_c_a_t_i_o_n___d_e_s_c_html"><div class="ttname"><a href="struct_d3_d12_m_a_1_1_v_i_r_t_u_a_l___a_l_l_o_c_a_t_i_o_n___d_e_s_c.html">D3D12MA::VIRTUAL_ALLOCATION_DESC</a></div><div class="ttdoc">Parameters of created virtual allocation to be passed to VirtualBlock::Allocate().</div><div class="ttdef"><b>Definition:</b> D3D12MemAlloc.h:1065</div></div>
<div class="ttc" id="astruct_d3_d12_m_a_1_1_v_i_r_t_u_a_l___a_l_l_o_c_a_t_i_o_n___d_e_s_c_html_a976b649e45abdd0769da0d79acde4bac"><div class="ttname"><a href="struct_d3_d12_m_a_1_1_v_i_r_t_u_a_l___a_l_l_o_c_a_t_i_o_n___d_e_s_c.html#a976b649e45abdd0769da0d79acde4bac">D3D12MA::VIRTUAL_ALLOCATION_DESC::Size</a></div><div class="ttdeci">UINT64 Size</div><div class="ttdoc">Size of the allocation.</div><div class="ttdef"><b>Definition:</b> D3D12MemAlloc.h:1072</div></div>
<div class="ttc" id="astruct_d3_d12_m_a_1_1_virtual_allocation_html"><div class="ttname"><a href="struct_d3_d12_m_a_1_1_virtual_allocation.html">D3D12MA::VirtualAllocation</a></div><div class="ttdoc">Represents single memory allocation done inside VirtualBlock.</div><div class="ttdef"><b>Definition:</b> D3D12MemAlloc.h:401</div></div>
</div><!-- fragment --><h1><a class="anchor" id="virtual_allocator_deallocation"></a>
Deallocation</h1>
<p >When no longer needed, an allocation can be freed by calling <a class="el" href="class_d3_d12_m_a_1_1_virtual_block.html#aab44e46bd122054c894fc84740f1e8fb" title="Frees the allocation.">D3D12MA::VirtualBlock::FreeAllocation</a>.</p>
@ -150,7 +150,7 @@ Alignment and units</h1>
<div class="line"><a class="code hl_struct" href="struct_d3_d12_m_a_1_1_virtual_allocation.html">D3D12MA::VirtualAllocation</a> alloc;</div>
<div class="line">UINT64 allocOffset;</div>
<div class="line">hr = block-&gt;<a class="code hl_function" href="class_d3_d12_m_a_1_1_virtual_block.html#a9281daf76e888ea1bd5247d5732e8179">Allocate</a>(&amp;allocDesc, &amp;alloc, &amp;allocOffset);</div>
<div class="ttc" id="astruct_d3_d12_m_a_1_1_v_i_r_t_u_a_l___a_l_l_o_c_a_t_i_o_n___d_e_s_c_html_aaa95e62f2f399339a09dcbb312a42de0"><div class="ttname"><a href="struct_d3_d12_m_a_1_1_v_i_r_t_u_a_l___a_l_l_o_c_a_t_i_o_n___d_e_s_c.html#aaa95e62f2f399339a09dcbb312a42de0">D3D12MA::VIRTUAL_ALLOCATION_DESC::Alignment</a></div><div class="ttdeci">UINT64 Alignment</div><div class="ttdoc">Required alignment of the allocation.</div><div class="ttdef"><b>Definition:</b> D3D12MemAlloc.h:1076</div></div>
<div class="ttc" id="astruct_d3_d12_m_a_1_1_v_i_r_t_u_a_l___a_l_l_o_c_a_t_i_o_n___d_e_s_c_html_aaa95e62f2f399339a09dcbb312a42de0"><div class="ttname"><a href="struct_d3_d12_m_a_1_1_v_i_r_t_u_a_l___a_l_l_o_c_a_t_i_o_n___d_e_s_c.html#aaa95e62f2f399339a09dcbb312a42de0">D3D12MA::VIRTUAL_ALLOCATION_DESC::Alignment</a></div><div class="ttdeci">UINT64 Alignment</div><div class="ttdoc">Required alignment of the allocation.</div><div class="ttdef"><b>Definition:</b> D3D12MemAlloc.h:1077</div></div>
</div><!-- fragment --><p >Alignments of different allocations made from one block may vary. However, if all alignments and sizes are always multiply of some size e.g. 4 B or <code>sizeof(MyDataStruct)</code>, you can express all sizes, alignments, and offsets in multiples of that size instead of individual bytes. It might be more convenient, but you need to make sure to use this new unit consistently in all the places:</p>
<ul>
<li><a class="el" href="struct_d3_d12_m_a_1_1_v_i_r_t_u_a_l___b_l_o_c_k___d_e_s_c.html#ac56491679f276a5a9956ed99bc4654e4" title="Total size of the block.">D3D12MA::VIRTUAL_BLOCK_DESC::Size</a></li>
@ -165,9 +165,9 @@ Statistics</h1>
<div class="line">printf(<span class="stringliteral">&quot;My virtual block has %llu bytes used by %u virtual allocations\n&quot;</span>,</div>
<div class="line"> stats.<a class="code hl_variable" href="struct_d3_d12_m_a_1_1_statistics.html#a53cfe3d241124b5a8e8058871a4b50e8">AllocationBytes</a>, stats.<a class="code hl_variable" href="struct_d3_d12_m_a_1_1_statistics.html#aef88ac53531db43a8888ad2be4a06c68">AllocationCount</a>);</div>
<div class="ttc" id="aclass_d3_d12_m_a_1_1_virtual_block_html_a0f1dda0e019e218b021f64987a74b110"><div class="ttname"><a href="class_d3_d12_m_a_1_1_virtual_block.html#a0f1dda0e019e218b021f64987a74b110">D3D12MA::VirtualBlock::GetStatistics</a></div><div class="ttdeci">void GetStatistics(Statistics *pStats) const</div><div class="ttdoc">Retrieves basic statistics of the virtual block that are fast to calculate.</div></div>
<div class="ttc" id="astruct_d3_d12_m_a_1_1_statistics_html"><div class="ttname"><a href="struct_d3_d12_m_a_1_1_statistics.html">D3D12MA::Statistics</a></div><div class="ttdoc">Calculated statistics of memory usage e.g. in a specific memory heap type, memory segment group,...</div><div class="ttdef"><b>Definition:</b> D3D12MemAlloc.h:280</div></div>
<div class="ttc" id="astruct_d3_d12_m_a_1_1_statistics_html_a53cfe3d241124b5a8e8058871a4b50e8"><div class="ttname"><a href="struct_d3_d12_m_a_1_1_statistics.html#a53cfe3d241124b5a8e8058871a4b50e8">D3D12MA::Statistics::AllocationBytes</a></div><div class="ttdeci">UINT64 AllocationBytes</div><div class="ttdoc">Total number of bytes occupied by all D3D12MA::Allocation objects.</div><div class="ttdef"><b>Definition:</b> D3D12MemAlloc.h:298</div></div>
<div class="ttc" id="astruct_d3_d12_m_a_1_1_statistics_html_aef88ac53531db43a8888ad2be4a06c68"><div class="ttname"><a href="struct_d3_d12_m_a_1_1_statistics.html#aef88ac53531db43a8888ad2be4a06c68">D3D12MA::Statistics::AllocationCount</a></div><div class="ttdeci">UINT AllocationCount</div><div class="ttdoc">Number of D3D12MA::Allocation objects allocated.</div><div class="ttdef"><b>Definition:</b> D3D12MemAlloc.h:288</div></div>
<div class="ttc" id="astruct_d3_d12_m_a_1_1_statistics_html"><div class="ttname"><a href="struct_d3_d12_m_a_1_1_statistics.html">D3D12MA::Statistics</a></div><div class="ttdoc">Calculated statistics of memory usage e.g. in a specific memory heap type, memory segment group,...</div><div class="ttdef"><b>Definition:</b> D3D12MemAlloc.h:281</div></div>
<div class="ttc" id="astruct_d3_d12_m_a_1_1_statistics_html_a53cfe3d241124b5a8e8058871a4b50e8"><div class="ttname"><a href="struct_d3_d12_m_a_1_1_statistics.html#a53cfe3d241124b5a8e8058871a4b50e8">D3D12MA::Statistics::AllocationBytes</a></div><div class="ttdeci">UINT64 AllocationBytes</div><div class="ttdoc">Total number of bytes occupied by all D3D12MA::Allocation objects.</div><div class="ttdef"><b>Definition:</b> D3D12MemAlloc.h:299</div></div>
<div class="ttc" id="astruct_d3_d12_m_a_1_1_statistics_html_aef88ac53531db43a8888ad2be4a06c68"><div class="ttname"><a href="struct_d3_d12_m_a_1_1_statistics.html#aef88ac53531db43a8888ad2be4a06c68">D3D12MA::Statistics::AllocationCount</a></div><div class="ttdeci">UINT AllocationCount</div><div class="ttdoc">Number of D3D12MA::Allocation objects allocated.</div><div class="ttdef"><b>Definition:</b> D3D12MemAlloc.h:289</div></div>
</div><!-- fragment --><p >More detailed statistics can be obtained using function <a class="el" href="class_d3_d12_m_a_1_1_virtual_block.html#a614a82247ce6cf29c38895e16eb971d9" title="Retrieves detailed statistics of the virtual block that are slower to calculate.">D3D12MA::VirtualBlock::CalculateStatistics()</a>, but they are slower to calculate.</p>
<p >You can also request a full list of allocations and free regions as a string in JSON format by calling <a class="el" href="class_d3_d12_m_a_1_1_virtual_block.html#a828a27070bfa762cae796d4c8f2ef703" title="Builds and returns statistics as a string in JSON format, including the list of allocations with thei...">D3D12MA::VirtualBlock::BuildStatsString</a>. Returned string must be later freed using <a class="el" href="class_d3_d12_m_a_1_1_virtual_block.html#a6f78ddaa7da194e239089e52093e68a9" title="Frees memory of a string returned from VirtualBlock::BuildStatsString.">D3D12MA::VirtualBlock::FreeStatsString</a>. The format of this string may differ from the one returned by the main D3D12 allocator, but it is similar.</p>
<h1><a class="anchor" id="virtual_allocator_additional_considerations"></a>

View File

@ -47,6 +47,7 @@ Documentation of all members: D3D12MemAlloc.h
- [Debug margins](@ref debug_margins)
- \subpage general_considerations
- [Thread safety](@ref general_considerations_thread_safety)
- [Versioning and compatibility](@ref general_considerations_versioning_and_compatibility)
- [Features not supported](@ref general_considerations_features_not_supported)
\section main_see_also See also
@ -388,7 +389,7 @@ struct Budget
It might be different (most probably smaller) than memory capacity returned
by D3D12MA::Allocator::GetMemoryCapacity() due to factors
external to the program, like other programs also consuming system resources.
external to the program, decided by the operating system.
Difference `BudgetBytes - UsageBytes` is the amount of additional memory that can probably
be allocated without problems. Exceeding the budget may result in various problems.
*/
@ -1284,7 +1285,7 @@ resourceDesc.Layout = D3D12_TEXTURE_LAYOUT_UNKNOWN;
resourceDesc.Flags = D3D12_RESOURCE_FLAG_NONE;
D3D12MA::ALLOCATION_DESC allocationDesc = {};
allocDesc.HeapType = D3D12_HEAP_TYPE_DEFAULT;
allocationDesc.HeapType = D3D12_HEAP_TYPE_DEFAULT;
D3D12Resource* resource;
D3D12MA::Allocation* allocation;
@ -1433,7 +1434,7 @@ more opportunities for internal optimizations, custom pools may be useful in fol
- To keep some resources separate from others in memory.
- To keep track of memory usage of just a specific group of resources. %Statistics can be queried using
D3D12MA::Pool::CalculateStats.
D3D12MA::Pool::CalculateStatistics.
- To use specific size of a memory block (`ID3D12Heap`). To set it, use member D3D12MA::POOL_DESC::BlockSize.
When set to 0, the library uses automatically determined, variable block sizes.
- To reserve some minimum amount of memory allocated. To use it, set member D3D12MA::POOL_DESC::MinBlockCount.
@ -1975,6 +1976,28 @@ Margins do not apply to \ref virtual_allocator.
Using this flag may improve performance.
- D3D12MA::VirtualBlock is not safe to be used from multiple threads simultaneously.
\section general_considerations_versioning_and_compatibility Versioning and compatibility
The library uses [**Semantic Versioning**](https://semver.org/),
which means version numbers follow convention: Major.Minor.Patch (e.g. 2.3.0), where:
- Incremented Patch version means a release is backward- and forward-compatible,
introducing only some internal improvements, bug fixes, optimizations etc.
or changes that are out of scope of the official API described in this documentation.
- Incremented Minor version means a release is backward-compatible,
so existing code that uses the library should continue to work, while some new
symbols could have been added: new structures, functions, new values in existing
enums and bit flags, new structure members, but not new function parameters.
- Incrementing Major version means a release could break some backward compatibility.
All changes between official releases are documented in file "CHANGELOG.md".
\warning Backward compatiblity is considered on the level of C++ source code, not binary linkage.
Adding new members to existing structures is treated as backward compatible if initializing
the new members to binary zero results in the old behavior.
You should always fully initialize all library structures to zeros and not rely on their
exact binary size.
\section general_considerations_features_not_supported Features not supported
Features deliberately excluded from the scope of this library: