Fix vsg::DeviceFeatures.cpp to return a VkPhysicalDeviceFeatures2 to pass into VkDeviceCreateInfo.pNext.

include/vsg/vk/DeviceFeatures.h

@@ -2,7 +2,7 @@
 
 /* <editor-fold desc="MIT License">
 
-Copyright(c) 2021 Robert Osfield
+Copyright(c) 2021 Robert Osfield, 2026 Stefan Kaps
 
 Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:
 
@@ -12,7 +12,8 @@ THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLI
 
 </editor-fold> */
 
-#include <map>
+#include <algorithm>
+#include <list>
 #include <vsg/io/Logger.h>
 #include <vsg/vk/PhysicalDevice.h>
 
@@ -37,15 +38,21 @@ namespace vsg
         template<typename FeatureStruct, VkStructureType type>
         FeatureStruct& get()
         {
-            if (auto itr = _features.find(type); itr != _features.end()) return *reinterpret_cast<FeatureStruct*>(itr->second.first);
-
-            FeatureStruct* feature = new FeatureStruct{};
-
-            feature->sType = type;
-            feature->pNext = nullptr;
-
-            _features[type].first = reinterpret_cast<FeatureHeader*>(feature);
-            _features[type].second = [](FeatureHeader* ptr) { delete reinterpret_cast<FeatureStruct*>(ptr); };
+            auto it = std::find_if(_features.begin(), _features.end(),
+                                   [](const auto& p) { return p.first->sType == type; });
+            if (it != _features.end()) return *reinterpret_cast<FeatureStruct*>(it->first);
+
+            if constexpr (type == VK_STRUCTURE_TYPE_PHYSICAL_DEVICE_FEATURES_2)
+                it = _features.begin();
+            else
+            { // as soon as we WILL create another type, we also need the base
+                if (_features.front().first->sType != VK_STRUCTURE_TYPE_PHYSICAL_DEVICE_FEATURES_2)
+                    get<VkPhysicalDeviceFeatures2, VK_STRUCTURE_TYPE_PHYSICAL_DEVICE_FEATURES_2>();
+                it = _features.end();
+            }
+
+            FeatureStruct* feature = new FeatureStruct{type, nullptr};
+            _features.emplace(it, (FeatureHeader*)feature, [](FeatureHeader* ptr) { delete reinterpret_cast<FeatureStruct*>(ptr); });
 
             return *feature;
         }
@@ -74,7 +81,7 @@ namespace vsg
 
         using DeleteHandler = void (*)(FeatureHeader* ptr);
 
-        std::map<VkStructureType, std::pair<FeatureHeader*, DeleteHandler>> _features;
+        std::list<std::pair<FeatureHeader*, DeleteHandler>> _features;
     };
     VSG_type_name(vsg::DeviceFeatures);
 

src/vsg/vk/DeviceFeatures.cpp

@@ -14,9 +14,7 @@ THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLI
 
 using namespace vsg;
 
-DeviceFeatures::DeviceFeatures()
-{
-}
+DeviceFeatures::DeviceFeatures() {}
 
 DeviceFeatures::~DeviceFeatures()
 {
@@ -32,7 +30,7 @@ void DeviceFeatures::clear()
 {
     for (auto& feature : _features)
     {
-        feature.second.second(feature.second.first);
+        feature.second(feature.first);
     }
 
     _features.clear();
@@ -43,13 +41,13 @@ void* DeviceFeatures::data() const
     if (_features.empty()) return nullptr;
 
     // chain the Feature pNext pointers together
-    FeatureHeader* previous = nullptr;
-    for (auto itr = _features.rbegin(); itr != _features.rend(); ++itr)
-    {
-        itr->second.first->pNext = previous;
-        previous = itr->second.first;
-    }
+    FeatureHeader *first{nullptr}, *prev{nullptr};
+    for (auto it : _features)
+        if (first)
+            prev->pNext = it.first, prev = it.first;
+        else
+            first = prev = it.first;
 
     // return head of the chain
-    return const_cast<void*>(reinterpret_cast<const void*>(_features.begin()->second.first));
+    return const_cast<void*>(reinterpret_cast<const void*>(first));
 }