Written more documentation - about lost allocations.

This commit is contained in:
Adam Sawicki 2018-03-09 18:18:34 +01:00
parent 67a2328f8c
commit 7568dfce76
8 changed files with 169 additions and 137 deletions

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@ -98,7 +98,7 @@ Classes</h2></td></tr>
<tr class="memdesc:"><td class="mdescLeft">&#160;</td><td class="mdescRight">Describes parameter of existing <code>VmaPool</code>. <a href="struct_vma_pool_stats.html#details">More...</a><br /></td></tr>
<tr class="separator:"><td class="memSeparator" colspan="2">&#160;</td></tr>
<tr class="memitem:"><td class="memItemLeft" align="right" valign="top">struct &#160;</td><td class="memItemRight" valign="bottom"><a class="el" href="struct_vma_allocation_info.html">VmaAllocationInfo</a></td></tr>
<tr class="memdesc:"><td class="mdescLeft">&#160;</td><td class="mdescRight">Parameters of <code>VmaAllocation</code> objects, that can be retrieved using function <a class="el" href="vk__mem__alloc_8h.html#a86dd08aba8633bfa4ad0df2e76481d8b" title="Returns current information about specified allocation. ">vmaGetAllocationInfo()</a>. <a href="struct_vma_allocation_info.html#details">More...</a><br /></td></tr>
<tr class="memdesc:"><td class="mdescLeft">&#160;</td><td class="mdescRight">Parameters of <code>VmaAllocation</code> objects, that can be retrieved using function <a class="el" href="vk__mem__alloc_8h.html#a86dd08aba8633bfa4ad0df2e76481d8b" title="Returns current information about specified allocation and atomically marks it as used in current fra...">vmaGetAllocationInfo()</a>. <a href="struct_vma_allocation_info.html#details">More...</a><br /></td></tr>
<tr class="separator:"><td class="memSeparator" colspan="2">&#160;</td></tr>
<tr class="memitem:"><td class="memItemLeft" align="right" valign="top">struct &#160;</td><td class="memItemRight" valign="bottom"><a class="el" href="struct_vma_defragmentation_info.html">VmaDefragmentationInfo</a></td></tr>
<tr class="memdesc:"><td class="mdescLeft">&#160;</td><td class="mdescRight">Optional configuration parameters to be passed to function <a class="el" href="vk__mem__alloc_8h.html#a6aced90fcc7b39882b6654a740a0b9bb" title="Compacts memory by moving allocations. ">vmaDefragment()</a>. <a href="struct_vma_defragmentation_info.html#details">More...</a><br /></td></tr>
@ -161,7 +161,7 @@ Typedefs</h2></td></tr>
<tr class="memdesc:a2e5612d871d64c5624087b837a338c34"><td class="mdescLeft">&#160;</td><td class="mdescRight">Describes parameter of existing <code>VmaPool</code>. <a href="#a2e5612d871d64c5624087b837a338c34">More...</a><br /></td></tr>
<tr class="separator:a2e5612d871d64c5624087b837a338c34"><td class="memSeparator" colspan="2">&#160;</td></tr>
<tr class="memitem:a795e6ff02a21d5486c0565f403dd9255"><td class="memItemLeft" align="right" valign="top">typedef struct <a class="el" href="struct_vma_allocation_info.html">VmaAllocationInfo</a>&#160;</td><td class="memItemRight" valign="bottom"><a class="el" href="vk__mem__alloc_8h.html#a795e6ff02a21d5486c0565f403dd9255">VmaAllocationInfo</a></td></tr>
<tr class="memdesc:a795e6ff02a21d5486c0565f403dd9255"><td class="mdescLeft">&#160;</td><td class="mdescRight">Parameters of <code>VmaAllocation</code> objects, that can be retrieved using function <a class="el" href="vk__mem__alloc_8h.html#a86dd08aba8633bfa4ad0df2e76481d8b" title="Returns current information about specified allocation. ">vmaGetAllocationInfo()</a>. <a href="#a795e6ff02a21d5486c0565f403dd9255">More...</a><br /></td></tr>
<tr class="memdesc:a795e6ff02a21d5486c0565f403dd9255"><td class="mdescLeft">&#160;</td><td class="mdescRight">Parameters of <code>VmaAllocation</code> objects, that can be retrieved using function <a class="el" href="vk__mem__alloc_8h.html#a86dd08aba8633bfa4ad0df2e76481d8b" title="Returns current information about specified allocation and atomically marks it as used in current fra...">vmaGetAllocationInfo()</a>. <a href="#a795e6ff02a21d5486c0565f403dd9255">More...</a><br /></td></tr>
<tr class="separator:a795e6ff02a21d5486c0565f403dd9255"><td class="memSeparator" colspan="2">&#160;</td></tr>
<tr class="memitem:ae67f8573a0cf20f16f0a1eecbca566a0"><td class="memItemLeft" align="right" valign="top">typedef struct <a class="el" href="struct_vma_defragmentation_info.html">VmaDefragmentationInfo</a>&#160;</td><td class="memItemRight" valign="bottom"><a class="el" href="vk__mem__alloc_8h.html#ae67f8573a0cf20f16f0a1eecbca566a0">VmaDefragmentationInfo</a></td></tr>
<tr class="memdesc:ae67f8573a0cf20f16f0a1eecbca566a0"><td class="mdescLeft">&#160;</td><td class="mdescRight">Optional configuration parameters to be passed to function <a class="el" href="vk__mem__alloc_8h.html#a6aced90fcc7b39882b6654a740a0b9bb" title="Compacts memory by moving allocations. ">vmaDefragment()</a>. <a href="#ae67f8573a0cf20f16f0a1eecbca566a0">More...</a><br /></td></tr>
@ -267,10 +267,10 @@ Functions</h2></td></tr>
<tr class="memdesc:a11f0fbc034fa81a4efedd73d61ce7568"><td class="mdescLeft">&#160;</td><td class="mdescRight">Frees memory previously allocated using <a class="el" href="vk__mem__alloc_8h.html#abf28077dbf82d0908b8acbe8ee8dd9b8" title="General purpose memory allocation. ">vmaAllocateMemory()</a>, <a class="el" href="vk__mem__alloc_8h.html#a7fdf64415b6c3d83c454f28d2c53df7b">vmaAllocateMemoryForBuffer()</a>, or <a class="el" href="vk__mem__alloc_8h.html#a0faa3f9e5fb233d29d1e00390650febb" title="Function similar to vmaAllocateMemoryForBuffer(). ">vmaAllocateMemoryForImage()</a>. <a href="#a11f0fbc034fa81a4efedd73d61ce7568">More...</a><br /></td></tr>
<tr class="separator:a11f0fbc034fa81a4efedd73d61ce7568"><td class="memSeparator" colspan="2">&#160;</td></tr>
<tr class="memitem:a86dd08aba8633bfa4ad0df2e76481d8b"><td class="memItemLeft" align="right" valign="top">void&#160;</td><td class="memItemRight" valign="bottom"><a class="el" href="vk__mem__alloc_8h.html#a86dd08aba8633bfa4ad0df2e76481d8b">vmaGetAllocationInfo</a> (VmaAllocator allocator, VmaAllocation allocation, <a class="el" href="struct_vma_allocation_info.html">VmaAllocationInfo</a> *pAllocationInfo)</td></tr>
<tr class="memdesc:a86dd08aba8633bfa4ad0df2e76481d8b"><td class="mdescLeft">&#160;</td><td class="mdescRight">Returns current information about specified allocation. <a href="#a86dd08aba8633bfa4ad0df2e76481d8b">More...</a><br /></td></tr>
<tr class="memdesc:a86dd08aba8633bfa4ad0df2e76481d8b"><td class="mdescLeft">&#160;</td><td class="mdescRight">Returns current information about specified allocation and atomically marks it as used in current frame. <a href="#a86dd08aba8633bfa4ad0df2e76481d8b">More...</a><br /></td></tr>
<tr class="separator:a86dd08aba8633bfa4ad0df2e76481d8b"><td class="memSeparator" colspan="2">&#160;</td></tr>
<tr class="memitem:a43d8ba9673c846f049089a5029d5c73a"><td class="memItemLeft" align="right" valign="top">VkBool32&#160;</td><td class="memItemRight" valign="bottom"><a class="el" href="vk__mem__alloc_8h.html#a43d8ba9673c846f049089a5029d5c73a">vmaTouchAllocation</a> (VmaAllocator allocator, VmaAllocation allocation)</td></tr>
<tr class="memdesc:a43d8ba9673c846f049089a5029d5c73a"><td class="mdescLeft">&#160;</td><td class="mdescRight">TODO finish documentation... <a href="#a43d8ba9673c846f049089a5029d5c73a">More...</a><br /></td></tr>
<tr class="memdesc:a43d8ba9673c846f049089a5029d5c73a"><td class="mdescLeft">&#160;</td><td class="mdescRight">Returns <code>VK_TRUE</code> if allocation is not lost and atomically marks it as used in current frame. <a href="#a43d8ba9673c846f049089a5029d5c73a">More...</a><br /></td></tr>
<tr class="separator:a43d8ba9673c846f049089a5029d5c73a"><td class="memSeparator" colspan="2">&#160;</td></tr>
<tr class="memitem:af9147d31ffc11d62fc187bde283ed14f"><td class="memItemLeft" align="right" valign="top">void&#160;</td><td class="memItemRight" valign="bottom"><a class="el" href="vk__mem__alloc_8h.html#af9147d31ffc11d62fc187bde283ed14f">vmaSetAllocationUserData</a> (VmaAllocator allocator, VmaAllocation allocation, void *pUserData)</td></tr>
<tr class="memdesc:af9147d31ffc11d62fc187bde283ed14f"><td class="mdescLeft">&#160;</td><td class="mdescRight">Sets pUserData in given allocation to new value. <a href="#af9147d31ffc11d62fc187bde283ed14f">More...</a><br /></td></tr>
@ -403,7 +403,7 @@ Functions</h2></td></tr>
</table>
</div><div class="memdoc">
<p>Parameters of <code>VmaAllocation</code> objects, that can be retrieved using function <a class="el" href="vk__mem__alloc_8h.html#a86dd08aba8633bfa4ad0df2e76481d8b" title="Returns current information about specified allocation. ">vmaGetAllocationInfo()</a>. </p>
<p>Parameters of <code>VmaAllocation</code> objects, that can be retrieved using function <a class="el" href="vk__mem__alloc_8h.html#a86dd08aba8633bfa4ad0df2e76481d8b" title="Returns current information about specified allocation and atomically marks it as used in current fra...">vmaGetAllocationInfo()</a>. </p>
</div>
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@ -659,7 +659,7 @@ Functions</h2></td></tr>
<p>You should not use this flag together with <a class="el" href="vk__mem__alloc_8h.html#ad9889c10c798b040d59c92f257cae597a5f436af6c8fe8540573a6d22627a6fd2">VMA_ALLOCATION_CREATE_CAN_BECOME_LOST_BIT</a>. </p>
</td></tr>
<tr><td class="fieldname"><a id="ad9889c10c798b040d59c92f257cae597a5f436af6c8fe8540573a6d22627a6fd2"></a>VMA_ALLOCATION_CREATE_CAN_BECOME_LOST_BIT&#160;</td><td class="fielddoc"><p>Allocation created with this flag can become lost as a result of another allocation with <a class="el" href="vk__mem__alloc_8h.html#ad9889c10c798b040d59c92f257cae597a68686d0ce9beb0d4d1b9f2b8b1389a7e">VMA_ALLOCATION_CREATE_CAN_MAKE_OTHER_LOST_BIT</a> flag, so you must check it before use.</p>
<p>To check if allocation is not lost, call <a class="el" href="vk__mem__alloc_8h.html#a86dd08aba8633bfa4ad0df2e76481d8b" title="Returns current information about specified allocation. ">vmaGetAllocationInfo()</a> and check if <a class="el" href="struct_vma_allocation_info.html#ae0bfb7dfdf79a76ffefc9a94677a2f67" title="Handle to Vulkan memory object. ">VmaAllocationInfo::deviceMemory</a> is not <code>VK_NULL_HANDLE</code>.</p>
<p>To check if allocation is not lost, call <a class="el" href="vk__mem__alloc_8h.html#a86dd08aba8633bfa4ad0df2e76481d8b" title="Returns current information about specified allocation and atomically marks it as used in current fra...">vmaGetAllocationInfo()</a> and check if <a class="el" href="struct_vma_allocation_info.html#ae0bfb7dfdf79a76ffefc9a94677a2f67" title="Handle to Vulkan memory object. ">VmaAllocationInfo::deviceMemory</a> is not <code>VK_NULL_HANDLE</code>.</p>
<p>For details about supporting lost allocations, see Lost Allocations chapter of User Guide on Main Page.</p>
<p>You should not use this flag together with <a class="el" href="vk__mem__alloc_8h.html#ad9889c10c798b040d59c92f257cae597a11da372cc3a82931c5e5d6146cd9dd1f" title="Set this flag to use a memory that will be persistently mapped and retrieve pointer to it...">VMA_ALLOCATION_CREATE_MAPPED_BIT</a>. </p>
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@ -820,7 +820,7 @@ Functions</h2></td></tr>
<dl class="params"><dt>Parameters</dt><dd>
<table class="params">
<tr><td class="paramdir">[out]</td><td class="paramname">pAllocation</td><td>Handle to allocated memory. </td></tr>
<tr><td class="paramdir">[out]</td><td class="paramname">pAllocationInfo</td><td>Optional. Information about allocated memory. It can be later fetched using function <a class="el" href="vk__mem__alloc_8h.html#a86dd08aba8633bfa4ad0df2e76481d8b" title="Returns current information about specified allocation. ">vmaGetAllocationInfo()</a>.</td></tr>
<tr><td class="paramdir">[out]</td><td class="paramname">pAllocationInfo</td><td>Optional. Information about allocated memory. It can be later fetched using function <a class="el" href="vk__mem__alloc_8h.html#a86dd08aba8633bfa4ad0df2e76481d8b" title="Returns current information about specified allocation and atomically marks it as used in current fra...">vmaGetAllocationInfo()</a>.</td></tr>
</table>
</dd>
</dl>
@ -875,7 +875,7 @@ Functions</h2></td></tr>
<dl class="params"><dt>Parameters</dt><dd>
<table class="params">
<tr><td class="paramdir">[out]</td><td class="paramname">pAllocation</td><td>Handle to allocated memory. </td></tr>
<tr><td class="paramdir">[out]</td><td class="paramname">pAllocationInfo</td><td>Optional. Information about allocated memory. It can be later fetched using function <a class="el" href="vk__mem__alloc_8h.html#a86dd08aba8633bfa4ad0df2e76481d8b" title="Returns current information about specified allocation. ">vmaGetAllocationInfo()</a>.</td></tr>
<tr><td class="paramdir">[out]</td><td class="paramname">pAllocationInfo</td><td>Optional. Information about allocated memory. It can be later fetched using function <a class="el" href="vk__mem__alloc_8h.html#a86dd08aba8633bfa4ad0df2e76481d8b" title="Returns current information about specified allocation and atomically marks it as used in current fra...">vmaGetAllocationInfo()</a>.</td></tr>
</table>
</dd>
</dl>
@ -1086,7 +1086,7 @@ Functions</h2></td></tr>
<table class="params">
<tr><td class="paramdir">[out]</td><td class="paramname">pBuffer</td><td>Buffer that was created. </td></tr>
<tr><td class="paramdir">[out]</td><td class="paramname">pAllocation</td><td>Allocation that was created. </td></tr>
<tr><td class="paramdir">[out]</td><td class="paramname">pAllocationInfo</td><td>Optional. Information about allocated memory. It can be later fetched using function <a class="el" href="vk__mem__alloc_8h.html#a86dd08aba8633bfa4ad0df2e76481d8b" title="Returns current information about specified allocation. ">vmaGetAllocationInfo()</a>.</td></tr>
<tr><td class="paramdir">[out]</td><td class="paramname">pAllocationInfo</td><td>Optional. Information about allocated memory. It can be later fetched using function <a class="el" href="vk__mem__alloc_8h.html#a86dd08aba8633bfa4ad0df2e76481d8b" title="Returns current information about specified allocation and atomically marks it as used in current fra...">vmaGetAllocationInfo()</a>.</td></tr>
</table>
</dd>
</dl>
@ -1303,7 +1303,7 @@ Functions</h2></td></tr>
<li>You must not pass same <code>VmaAllocation</code> object multiple times in pAllocations array.</li>
</ul>
<p>The function also frees empty <code>VkDeviceMemory</code> blocks.</p>
<p>After allocation has been moved, its <a class="el" href="struct_vma_allocation_info.html#ae0bfb7dfdf79a76ffefc9a94677a2f67" title="Handle to Vulkan memory object. ">VmaAllocationInfo::deviceMemory</a> and/or <a class="el" href="struct_vma_allocation_info.html#a4a3c732388dbdc7a23f9365b00825268" title="Offset into deviceMemory object to the beginning of this allocation, in bytes. (deviceMemory, offset) pair is unique to this allocation. ">VmaAllocationInfo::offset</a> changes. You must query them again using <a class="el" href="vk__mem__alloc_8h.html#a86dd08aba8633bfa4ad0df2e76481d8b" title="Returns current information about specified allocation. ">vmaGetAllocationInfo()</a> if you need them.</p>
<p>After allocation has been moved, its <a class="el" href="struct_vma_allocation_info.html#ae0bfb7dfdf79a76ffefc9a94677a2f67" title="Handle to Vulkan memory object. ">VmaAllocationInfo::deviceMemory</a> and/or <a class="el" href="struct_vma_allocation_info.html#a4a3c732388dbdc7a23f9365b00825268" title="Offset into deviceMemory object to the beginning of this allocation, in bytes. (deviceMemory, offset) pair is unique to this allocation. ">VmaAllocationInfo::offset</a> changes. You must query them again using <a class="el" href="vk__mem__alloc_8h.html#a86dd08aba8633bfa4ad0df2e76481d8b" title="Returns current information about specified allocation and atomically marks it as used in current fra...">vmaGetAllocationInfo()</a> if you need them.</p>
<p>If an allocation has been moved, data in memory is copied to new place automatically, but if it was bound to a buffer or an image, you must destroy that object yourself, create new one and bind it to the new memory pointed by the allocation. You must use <code>vkDestroyBuffer()</code>, <code>vkDestroyImage()</code>, <code>vkCreateBuffer()</code>, <code>vkCreateImage()</code> for that purpose and NOT <a class="el" href="vk__mem__alloc_8h.html#a0d9f4e4ba5bf9aab1f1c746387753d77" title="Destroys Vulkan buffer and frees allocated memory. ">vmaDestroyBuffer()</a>, <a class="el" href="vk__mem__alloc_8h.html#ae50d2cb3b4a3bfd4dd40987234e50e7e" title="Destroys Vulkan image and frees allocated memory. ">vmaDestroyImage()</a>, <a class="el" href="vk__mem__alloc_8h.html#ac72ee55598617e8eecca384e746bab51">vmaCreateBuffer()</a>, <a class="el" href="vk__mem__alloc_8h.html#a02a94f25679275851a53e82eacbcfc73" title="Function similar to vmaCreateBuffer(). ">vmaCreateImage()</a>! Example:</p>
<div class="fragment"><div class="line">VkDevice device = ...;</div><div class="line">VmaAllocator allocator = ...;</div><div class="line">std::vector&lt;VkBuffer&gt; buffers = ...;</div><div class="line">std::vector&lt;VmaAllocation&gt; allocations = ...;</div><div class="line"></div><div class="line">std::vector&lt;VkBool32&gt; allocationsChanged(allocations.size());</div><div class="line"><a class="code" href="vk__mem__alloc_8h.html#a6aced90fcc7b39882b6654a740a0b9bb">vmaDefragment</a>(allocator, allocations.data(), allocations.size(), allocationsChanged.data(), <span class="keyword">nullptr</span>, <span class="keyword">nullptr</span>);</div><div class="line"></div><div class="line"><span class="keywordflow">for</span>(<span class="keywordtype">size_t</span> i = 0; i &lt; allocations.size(); ++i)</div><div class="line">{</div><div class="line"> <span class="keywordflow">if</span>(allocationsChanged[i])</div><div class="line"> {</div><div class="line"> <a class="code" href="struct_vma_allocation_info.html">VmaAllocationInfo</a> allocInfo;</div><div class="line"> <a class="code" href="vk__mem__alloc_8h.html#a86dd08aba8633bfa4ad0df2e76481d8b">vmaGetAllocationInfo</a>(allocator, allocations[i], &amp;allocInfo);</div><div class="line"></div><div class="line"> vkDestroyBuffer(device, buffers[i], <span class="keyword">nullptr</span>);</div><div class="line"></div><div class="line"> VkBufferCreateInfo bufferInfo = ...;</div><div class="line"> vkCreateBuffer(device, &amp;bufferInfo, <span class="keyword">nullptr</span>, &amp;buffers[i]);</div><div class="line"> </div><div class="line"> <span class="comment">// You can make dummy call to vkGetBufferMemoryRequirements here to silence validation layer warning.</span></div><div class="line"> </div><div class="line"> vkBindBufferMemory(device, buffers[i], allocInfo.<a class="code" href="struct_vma_allocation_info.html#ae0bfb7dfdf79a76ffefc9a94677a2f67">deviceMemory</a>, allocInfo.<a class="code" href="struct_vma_allocation_info.html#a4a3c732388dbdc7a23f9365b00825268">offset</a>);</div><div class="line"> }</div><div class="line">}</div></div><!-- fragment --><p>Note: Please don't expect memory to be fully compacted after this call. Algorithms inside are based on some heuristics that try to maximize number of Vulkan memory blocks to make totally empty to release them, as well as to maximimze continuous empty space inside remaining blocks, while minimizing the number and size of data that needs to be moved. Some fragmentation still remains after this call. This is normal.</p>
<p>Warning: This function is not 100% correct according to Vulkan specification. Use it at your own risk. That's because Vulkan doesn't guarantee that memory requirements (size and alignment) for a new buffer or image are consistent. They may be different even for subsequent calls with the same parameters. It really does happen on some platforms, especially with images.</p>
@ -1675,8 +1675,14 @@ Functions</h2></td></tr>
</table>
</div><div class="memdoc">
<p>Returns current information about specified allocation. </p>
<p>It also "touches" allocation... TODO finish documentation. </p>
<p>Returns current information about specified allocation and atomically marks it as used in current frame. </p>
<p>Current paramters of given allocation are returned in <code>pAllocationInfo</code>.</p>
<p>This function also atomically "touches" allocation - marks it as used in current frame, just like <a class="el" href="vk__mem__alloc_8h.html#a43d8ba9673c846f049089a5029d5c73a" title="Returns VK_TRUE if allocation is not lost and atomically marks it as used in current frame...">vmaTouchAllocation()</a>. If the allocation is in lost state, <code>pAllocationInfo-&gt;deviceMemory == VK_NULL_HANDLE</code>.</p>
<p>Although this function uses atomics and doesn't lock any mutex, so it should be quite efficient, you can avoid calling it too often.</p>
<ul>
<li>You can retrieve same <a class="el" href="struct_vma_allocation_info.html" title="Parameters of VmaAllocation objects, that can be retrieved using function vmaGetAllocationInfo(). ">VmaAllocationInfo</a> structure while creating your resource, from function <a class="el" href="vk__mem__alloc_8h.html#ac72ee55598617e8eecca384e746bab51">vmaCreateBuffer()</a>, <a class="el" href="vk__mem__alloc_8h.html#a02a94f25679275851a53e82eacbcfc73" title="Function similar to vmaCreateBuffer(). ">vmaCreateImage()</a>. You can remember it if you are sure parameters don't change (e.g. due to defragmentation or allocation becoming lost).</li>
<li>If you just want to check if allocation is not lost, <a class="el" href="vk__mem__alloc_8h.html#a43d8ba9673c846f049089a5029d5c73a" title="Returns VK_TRUE if allocation is not lost and atomically marks it as used in current frame...">vmaTouchAllocation()</a> will work faster. </li>
</ul>
</div>
</div>
@ -1971,7 +1977,7 @@ Functions</h2></td></tr>
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<p>Sets index of the current frame. </p>
<p>This function must be used if you make allocations with <a class="el" href="vk__mem__alloc_8h.html#ad9889c10c798b040d59c92f257cae597a5f436af6c8fe8540573a6d22627a6fd2">VMA_ALLOCATION_CREATE_CAN_BECOME_LOST_BIT</a> and <a class="el" href="vk__mem__alloc_8h.html#ad9889c10c798b040d59c92f257cae597a68686d0ce9beb0d4d1b9f2b8b1389a7e">VMA_ALLOCATION_CREATE_CAN_MAKE_OTHER_LOST_BIT</a> flags to inform the allocator when a new frame begins. Allocations queried using <a class="el" href="vk__mem__alloc_8h.html#a86dd08aba8633bfa4ad0df2e76481d8b" title="Returns current information about specified allocation. ">vmaGetAllocationInfo()</a> cannot become lost in the current frame. </p>
<p>This function must be used if you make allocations with <a class="el" href="vk__mem__alloc_8h.html#ad9889c10c798b040d59c92f257cae597a5f436af6c8fe8540573a6d22627a6fd2">VMA_ALLOCATION_CREATE_CAN_BECOME_LOST_BIT</a> and <a class="el" href="vk__mem__alloc_8h.html#ad9889c10c798b040d59c92f257cae597a68686d0ce9beb0d4d1b9f2b8b1389a7e">VMA_ALLOCATION_CREATE_CAN_MAKE_OTHER_LOST_BIT</a> flags to inform the allocator when a new frame begins. Allocations queried using <a class="el" href="vk__mem__alloc_8h.html#a86dd08aba8633bfa4ad0df2e76481d8b" title="Returns current information about specified allocation and atomically marks it as used in current fra...">vmaGetAllocationInfo()</a> cannot become lost in the current frame. </p>
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<p>TODO finish documentation... </p>
<p>Returns <code>VK_TRUE</code> if allocation is not lost and atomically marks it as used in current frame. </p>
<p>If the allocation has been created with <a class="el" href="vk__mem__alloc_8h.html#ad9889c10c798b040d59c92f257cae597a5f436af6c8fe8540573a6d22627a6fd2">VMA_ALLOCATION_CREATE_CAN_BECOME_LOST_BIT</a> flag, this function returns <code>VK_TRUE</code> if it's not in lost state, so it can still be used. It then also atomically "touches" the allocation - marks it as used in current frame, so that you can be sure it won't become lost in current frame or next <code>frameInUseCount</code> frames.</p>
<p>If the allocation is in lost state, the function returns <code>VK_FALSE</code>. Memory of such allocation, as well as buffer or image bound to it, should not be used. Lost allocation and the buffer/image still need to be destroyed.</p>
<p>If the allocation has been created without <a class="el" href="vk__mem__alloc_8h.html#ad9889c10c798b040d59c92f257cae597a5f436af6c8fe8540573a6d22627a6fd2">VMA_ALLOCATION_CREATE_CAN_BECOME_LOST_BIT</a> flag, this function always returns <code>VK_TRUE</code>. </p>
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