Merge pull request #1433 from vsg-dev/viewMaxSlot

Restructured State::stateStack and ViewportState management for flexibility and efficiency.

Author: robertosfield

include/vsg/app/CommandGraph.h

@@ -39,8 +39,8 @@ namespace vsg
 
         int queueFamily = -1;
         int presentFamily = -1;
-        uint32_t maxSlot = 2;
         int submitOrder = 0;
+        Slots maxSlots;
 
         ref_ptr<RecordTraversal> getOrCreateRecordTraversal();
 

include/vsg/app/CompileManager.h

@@ -27,7 +27,7 @@ namespace vsg
     {
         int result = VK_INCOMPLETE;
         std::string message;
-        uint32_t maxSlot = 0;
+        Slots maxSlots;
         bool containsPagedLOD = false;
         ResourceRequirements::Views views;
         ResourceRequirements::DynamicData dynamicData;

include/vsg/app/RecordTraversal.h

@@ -16,6 +16,7 @@ THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLI
 #include <vsg/core/Object.h>
 #include <vsg/core/type_name.h>
 #include <vsg/maths/mat4.h>
+#include <vsg/vk/Slots.h>
 
 #include <set>
 #include <vector>
@@ -69,7 +70,7 @@ namespace vsg
     class VSG_DECLSPEC RecordTraversal : public Object
     {
     public:
-        explicit RecordTraversal(uint32_t in_maxSlot = 2, const std::set<Bin*>& in_bins = {});
+        explicit RecordTraversal(const Slots& in_maxSlots = {}, const std::set<Bin*>& in_bins = {});
 
         RecordTraversal(const RecordTraversal&) = delete;
         RecordTraversal& operator=(const RecordTraversal& rhs) = delete;

include/vsg/app/RenderGraph.h

@@ -17,6 +17,7 @@ THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLI
 #include <vsg/app/Camera.h>
 #include <vsg/app/Window.h>
 #include <vsg/app/WindowResizeHandler.h>
+#include <vsg/state/ResourceHints.h>
 
 namespace vsg
 {
@@ -67,6 +68,8 @@ namespace vsg
         /// Subpass contents setting passed to vkCmdBeginRenderPass
         VkSubpassContents contents = VK_SUBPASS_CONTENTS_INLINE;
 
+        uint32_t viewportStateHint = DYNAMIC_VIEWPORTSTATE;
+
         /// Callback used to automatically update viewports, scissors, renderArea and clears when the window is resized.
         /// By default resize handling is done.
         ref_ptr<WindowResizeHandler> windowResizeHandler;

include/vsg/app/WindowResizeHandler.h

@@ -44,6 +44,7 @@ namespace vsg
     class VSG_DECLSPEC WindowResizeHandler : public Inherit<Visitor, WindowResizeHandler>
     {
     public:
+        ref_ptr<Context> context;
         VkRect2D renderArea;
         VkExtent2D previous_extent;
         VkExtent2D new_extent;
@@ -64,6 +65,7 @@ namespace vsg
         /// return true if the object was visited
         bool visit(const Object* object, uint32_t index = 0);
 
+        void apply(BindGraphicsPipeline& bindPipeline) override;
         void apply(Object& object) override;
         void apply(ClearAttachments& clearAttachments) override;
         void apply(View& view) override;

include/vsg/state/ResourceHints.h

@@ -24,15 +24,21 @@ namespace vsg
         COMPILE_TRAVERSAL_USE_TRANSFER_TASK
     };
 
+    enum ViewportStateMask : uint32_t
+    {
+        STATIC_VIEWPORTSTATE = 1 << 0,
+        DYNAMIC_VIEWPORTSTATE = 1 << 1
+    };
+
     /// ResourceHints provides settings that help preallocation of Vulkan resources and memory.
     class VSG_DECLSPEC ResourceHints : public Inherit<Object, ResourceHints>
     {
     public:
         ResourceHints();
 
-        bool empty() const noexcept { return maxSlot == 0 && numDescriptorSets == 0 && descriptorPoolSizes.empty(); }
+        bool empty() const noexcept { return maxSlots.state == 0 && maxSlots.view == 0 && numDescriptorSets == 0 && descriptorPoolSizes.empty(); }
 
-        uint32_t maxSlot = 0;
+        Slots maxSlots;
         uint32_t numDescriptorSets = 0;
         DescriptorPoolSizes descriptorPoolSizes;
 
@@ -48,6 +54,7 @@ namespace vsg
         uint32_t numDatabasePagerReadThreads = 4;
 
         DataTransferHint dataTransferHint = COMPILE_TRAVERSAL_USE_TRANSFER_TASK;
+        uint32_t viewportStateHint = DYNAMIC_VIEWPORTSTATE;
 
     public:
         void read(Input& input) override;

include/vsg/vk/CommandBuffer.h

@@ -22,6 +22,7 @@ namespace vsg
     // forward declare
     class ViewDependentState;
     class GPUStatsCollection;
+    class State;
 
     /// CommandBuffer encapsulates VkCommandBuffer
     class VSG_DECLSPEC CommandBuffer : public Inherit<Object, CommandBuffer>
@@ -38,6 +39,7 @@ namespace vsg
         Mask traversalMask = MASK_ALL;
         Mask overrideMask = MASK_OFF;
         ViewDependentState* viewDependentState = nullptr;
+        State* state = nullptr;
         ref_ptr<GPUStatsCollection> gpuStats;
 
         VkCommandBufferLevel level() const { return _level; }
@@ -51,14 +53,7 @@ namespace vsg
         CommandPool* getCommandPool() { return _commandPool; }
         const CommandPool* getCommandPool() const { return _commandPool; }
 
-        void setCurrentPipelineLayout(const PipelineLayout* pipelineLayout)
-        {
-            _currentPipelineLayout = pipelineLayout->vk(deviceID);
-            if (pipelineLayout->pushConstantRanges.empty())
-                _currentPushConstantStageFlags = 0;
-            else
-                _currentPushConstantStageFlags = pipelineLayout->pushConstantRanges.front().stageFlags;
-        }
+        void setCurrentPipelineLayout(const PipelineLayout* pipelineLayout);
 
         VkPipelineLayout getCurrentPipelineLayout() const { return _currentPipelineLayout; }
         VkShaderStageFlags getCurrentPushConstantStageFlags() const { return _currentPushConstantStageFlags; }

include/vsg/vk/ResourceRequirements.h

@@ -88,7 +88,7 @@ namespace vsg
         Views views;
         ViewDetailStack viewDetailsStack;
 
-        uint32_t maxSlot = 0;
+        Slots maxSlots;
         uint32_t externalNumDescriptorSets = 0;
         bool containsPagedLOD = false;
 
@@ -102,6 +102,7 @@ namespace vsg
         uivec2 shadowMapSize = {2048, 2048};
 
         DataTransferHint dataTransferHint = COMPILE_TRAVERSAL_USE_TRANSFER_TASK;
+        uint32_t viewportStateHint = DYNAMIC_VIEWPORTSTATE;
     };
     VSG_type_name(vsg::ResourceRequirements);
 

include/vsg/vk/Slots.h

@@ -0,0 +1,37 @@
+#pragma once
+
+/* <editor-fold desc="MIT License">
+
+Copyright(c) 2025 Robert Osfield
+
+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:
+
+The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+
+</editor-fold> */
+
+namespace vsg
+{
+
+    /// max slot values used for general state and view state related State::stateStacks
+    struct Slots
+    {
+        uint32_t state = 0;
+        uint32_t view = 0;
+
+        /// return maximum of the state and view slot numbers
+        uint32_t max() const
+        {
+            return view > state ? view : state;
+        }
+
+        void merge(const Slots& rhs)
+        {
+            if (rhs.state > state) state = rhs.state;
+            if (rhs.view > view) view = rhs.view;
+        }
+    };
+
+} // namespace vsg

include/vsg/vk/State.h

@@ -26,48 +26,51 @@ namespace vsg
 {
 
 #define POLYTOPE_SIZE 5
+#define STATESTACK_SIZE 16
 
     /// StateStack used internally by vsg::State to manage stack of vsg::StateCommand
     template<class T>
     class StateStack
     {
     public:
-        StateStack() :
-            dirty(false) {}
+        StateStack() {}
 
-        using Stack = std::stack<ref_ptr<const T>>;
+        using Stack = std::array<const T*, STATESTACK_SIZE>;
         Stack stack;
-        bool dirty;
+        size_t pos = 0;
 
-        template<class R>
-        inline void push(ref_ptr<R> value)
+        inline void reset()
         {
-            stack.push(value);
-            dirty = true;
+            pos = 0;
+            stack[0] = nullptr;
         }
 
-        template<class R>
-        inline void push(R* value)
+        inline void dirty()
         {
-            stack.push(ref_ptr<const T>(value));
-            dirty = true;
+            stack[0] = nullptr;
+        }
+
+        inline void push(const T* value)
+        {
+            stack[++pos] = value;
         }
 
         inline void pop()
         {
-            stack.pop();
-            dirty = !stack.empty();
+            --pos;
         }
-        bool empty() const { return stack.empty(); }
-        size_t size() const { return stack.size(); }
-        const T* top() const { return stack.top(); }
+
+        bool empty() const { return pos == 0; }
+        size_t size() const { return pos; }
+        const T* top() const { return stack[pos]; }
 
         inline void record(CommandBuffer& commandBuffer)
         {
-            if (dirty)
+            const T* current = stack[pos];
+            if (current != stack[0])
             {
-                stack.top()->record(commandBuffer);
-                dirty = false;
+                current->record(commandBuffer);
+                stack[0] = current;
             }
         }
     };
@@ -228,11 +231,7 @@ namespace vsg
     class State : public Inherit<Object, State>
     {
     public:
-        explicit State(uint32_t maxSlot) :
-            dirty(false),
-            stateStacks(static_cast<size_t>(maxSlot) + 1)
-        {
-        }
+        explicit State(const Slots& in_maxSlots);
 
         using StateCommandStack = StateStack<StateCommand>;
         using StateStacks = std::vector<StateCommandStack>;
@@ -252,15 +251,28 @@ namespace vsg
         dmat4 inheritedViewMatrix;
         dmat4 inheritedViewTransform;
 
+        Slots maxSlots;
+        uint32_t activeMaxStateSlot = 0;
+
         StateStacks stateStacks;
 
+        uint32_t viewportStateHint = 0;
+
         MatrixStack projectionMatrixStack{0};
         MatrixStack modelviewMatrixStack{64};
 
-        void reserve(uint32_t maxSlot)
+        void reserve(const Slots& in_maxSlots);
+
+        void connect(ref_ptr<CommandBuffer> commandBuffer);
+
+        void reset();
+
+        inline void dirtyStateStacks()
         {
-            size_t required_size = static_cast<size_t>(maxSlot) + 1;
-            if (required_size > stateStacks.size()) stateStacks.resize(required_size);
+            for (auto& stateStack : stateStacks)
+            {
+                stateStack.dirty();
+            }
         }
 
         void setInhertiedViewProjectionAndViewMatrix(const dmat4& projMatrix, const dmat4& viewMatrix)
@@ -295,11 +307,14 @@ namespace vsg
         {
             if (dirty)
             {
-                for (auto& stateStack : stateStacks)
+                for (uint32_t slot = 0; slot <= activeMaxStateSlot; ++slot)
                 {
-                    stateStack.record(*_commandBuffer);
+                    stateStacks[slot].record(*_commandBuffer);
                 }
 
+                // reset the active maxslot to the minimum required
+                activeMaxStateSlot = maxSlots.state;
+
                 projectionMatrixStack.record(*_commandBuffer);
                 modelviewMatrixStack.record(*_commandBuffer);
 
@@ -349,6 +364,14 @@ namespace vsg
             dirty = true;
         }
 
+        void pushView(ref_ptr<StateCommand> command);
+
+        void popView(ref_ptr<StateCommand> command);
+
+        void pushView(const View& view);
+
+        void popView(const View& view);
+
         inline void pushFrustum()
         {
             _frustumStack.push(Frustum(_frustumProjected, modelviewMatrixStack.top()));