#5584: Start implementing container classes storing the winding vertices

include/iwindingrenderer.h

@@ -0,0 +1,40 @@
+#pragma once
+
+#include <vector>
+#include <limits>
+#include "render/ArbitraryMeshVertex.h"
+
+namespace render
+{
+
+/**
+ * A winding renderer accepts a variable number of windings and arranges them into 
+ * one or more continuous blocks of vertices for efficient rendering.
+ * 
+ * The internal arrangement has the goal of reducing the amount of draw calls for 
+ * winding sharing a single material. Allocating a winding slot yields a handle which
+ * allows for later update or deallocation of the slot.
+ * 
+ * Only the vertex data (XYZ, UV, Normals, Colour) needs to be submitted,
+ * the render indices of each winding slot are handled internally.
+ */
+class IWindingRenderer
+{
+public:
+    virtual ~IWindingRenderer() {}
+
+    using Slot = std::size_t;
+    static constexpr Slot InvalidSlot = std::numeric_limits<std::size_t>::max();
+
+    // Allocate a slot to hold the vertex data of a winding of the given size
+    // Returns the handle which can be used to update or deallocate the data later
+    virtual Slot allocateWinding(int size) = 0;
+
+    // Releases a previously allocated winding slot. This invalidates the handle.
+    virtual void deallocateWinding(Slot slot) = 0;
+
+    // Sets the winding data
+    virtual void updateWinding(Slot slot, const std::vector<ArbitraryMeshVertex>& vertices) = 0;
+};
+
+}

libs/render/CompactWindingVertexBuffer.h

@@ -0,0 +1,74 @@
+#pragma once
+
+#include <vector>
+
+namespace render
+{
+
+template<typename VertexT>
+class CompactWindingVertexBuffer
+{
+private:
+    std::size_t _size;
+    std::size_t _numIndicesPerWinding;
+
+    std::vector<VertexT> _vertices;
+
+    // The indices suitable for rendering triangles
+    std::vector<unsigned int> _indices;
+
+public:
+    CompactWindingVertexBuffer(std::size_t size) :
+        _size(size),
+        _numIndicesPerWinding(3 * (_size - 2))
+    {}
+
+    CompactWindingVertexBuffer(const CompactWindingVertexBuffer& other) = delete;
+    CompactWindingVertexBuffer& operator=(const CompactWindingVertexBuffer& other) = delete;
+
+    std::size_t getWindingSize() const
+    {
+        return _size;
+    }
+
+    std::size_t getNumIndicesPerWinding() const
+    {
+        return _numIndicesPerWinding;
+    }
+
+    const std::vector<VertexT>& getVertices() const
+    {
+        return _vertices;
+    }
+
+    const std::vector<unsigned int>& getIndices() const
+    {
+        return _indices;
+    }
+
+    // Appends the given winding data to the end of the buffer, returns the position in the array
+    std::size_t pushWinding(const std::vector<VertexT>& winding)
+    {
+        assert(winding.size() == _size);
+
+        auto currentSize = _vertices.size();
+        auto position = currentSize / _size;
+        _vertices.reserve(currentSize + _size); // reserve() never shrinks
+
+        std::copy(winding.begin(), winding.end(), std::back_inserter(_vertices));
+
+        // Allocate and calculate indices
+        _indices.reserve(_indices.size() + _numIndicesPerWinding);
+
+        for (unsigned int n = static_cast<unsigned int>(_size) - 1; n - 1 > 0; --n)
+        {
+            _indices.push_back(0);
+            _indices.push_back(n - 1);
+            _indices.push_back(n);
+        }
+
+        return position;
+    }
+};
+
+}

libs/render/WindingRenderer.h

@@ -0,0 +1,33 @@
+#pragma once
+
+#include "iwindingrenderer.h"
+
+namespace render
+{
+
+class WindingRenderer :
+    public IWindingRenderer
+{
+private:
+
+
+public:
+    Slot allocateWinding(int size) override
+    {
+        // Get the Bucket this Slot is referring to
+
+        return InvalidSlot;
+    }
+
+    void deallocateWinding(Slot slot) override
+    {
+
+    }
+
+    void updateWinding(Slot slot, const std::vector<ArbitraryMeshVertex>& vertices) override
+    {
+
+    }
+};
+
+}

test/WindingRendering.cpp

@@ -0,0 +1,69 @@
+#include "gtest/gtest.h"
+#include "render/ArbitraryMeshVertex.h"
+#include "render/WindingRenderer.h"
+#include "render/CompactWindingVertexBuffer.h"
+
+namespace test
+{
+
+using VertexBuffer = render::CompactWindingVertexBuffer<ArbitraryMeshVertex>;
+
+inline std::vector<ArbitraryMeshVertex> createWinding(int id, int size)
+{
+    std::vector<ArbitraryMeshVertex> winding;
+
+    for (int i = 0; i < size; ++i)
+    {
+        winding.emplace_back(ArbitraryMeshVertex({ id + 0.0, id + 0.5, id + 0.3 }, { 0, 0, id + 0.0 }, { id + 0.0, -id + 0.0 }));
+    }
+
+    return winding;
+}
+
+inline void checkWindingIndices(const VertexBuffer& buffer, std::size_t slot)
+{
+    // Slot must be within range
+    auto windingSize = buffer.getWindingSize();
+
+    EXPECT_LT(slot, buffer.getVertices().size() / windingSize);
+
+    // Assume the indices are within bounds
+    auto indexStart = buffer.getNumIndicesPerWinding() * slot;
+    EXPECT_LE(indexStart + buffer.getNumIndicesPerWinding(), buffer.getIndices().size());
+
+    // Check the indices, they must be referencing vertices in that slot
+    for (auto i = indexStart; i < indexStart + buffer.getNumIndicesPerWinding(); ++i)
+    {
+        auto index = buffer.getIndices().at(i);
+        EXPECT_GE(index, slot * windingSize) << "Winding index out of lower bounds";
+        EXPECT_LT(index, (slot + 1) * windingSize) << "Winding index out of upper bounds";
+    }
+}
+
+TEST(CompactWindingVertexBuffer, NumIndicesPerWinding)
+{
+    for (auto i = 0; i < 10; ++i)
+    {
+        VertexBuffer buffer(i);
+        EXPECT_EQ(buffer.getWindingSize(), i);
+        EXPECT_EQ(buffer.getNumIndicesPerWinding(), 3 * (buffer.getWindingSize() - 2));
+    }
+}
+
+TEST(CompactWindingVertexBuffer, AddSingleWinding)
+{
+    auto winding1 = createWinding(1, 4);
+
+    VertexBuffer buffer(4);
+
+    auto slot = buffer.pushWinding(winding1);
+
+    EXPECT_EQ(slot, 0) << "Wrong slot assignment";
+    EXPECT_EQ(buffer.getVertices().size(), 4);
+    EXPECT_EQ(buffer.getIndices().size(), buffer.getNumIndicesPerWinding());
+
+    // Assume that the indices have been correctly calculated
+    checkWindingIndices(buffer, slot);
+}
+
+}

tools/msvc/Tests/Tests.vcxproj

@@ -114,6 +114,7 @@
     <ClCompile Include="..\..\..\test\Transformation.cpp" />
     <ClCompile Include="..\..\..\test\UndoRedo.cpp" />
     <ClCompile Include="..\..\..\test\VFS.cpp" />
+    <ClCompile Include="..\..\..\test\WindingRendering.cpp" />
     <ClCompile Include="..\..\..\test\WorldspawnColour.cpp" />
   </ItemGroup>
   <ItemGroup>

tools/msvc/Tests/Tests.vcxproj.filters

@@ -52,6 +52,7 @@
     <ClCompile Include="..\..\..\test\TextureManipulation.cpp" />
     <ClCompile Include="..\..\..\test\EntityInspector.cpp" />
     <ClCompile Include="..\..\..\test\UndoRedo.cpp" />
+    <ClCompile Include="..\..\..\test\WindingRendering.cpp" />
   </ItemGroup>
   <ItemGroup>
     <ClInclude Include="..\..\..\test\HeadlessOpenGLContext.h" />

tools/msvc/include.vcxproj

@@ -197,6 +197,7 @@
     <ClInclude Include="..\..\include\iundo.h" />
     <ClInclude Include="..\..\include\iversioncontrol.h" />
     <ClInclude Include="..\..\include\ivolumetest.h" />
+    <ClInclude Include="..\..\include\iwindingrenderer.h" />
     <ClInclude Include="..\..\include\modelskin.h" />
     <ClInclude Include="..\..\include\ModResource.h" />
     <ClInclude Include="..\..\include\precompiled_interfaces.h" />

tools/msvc/include.vcxproj.filters

@@ -162,6 +162,7 @@
       <Filter>ui</Filter>
     </ClInclude>
     <ClInclude Include="..\..\include\imapfilechangetracker.h" />
+    <ClInclude Include="..\..\include\iwindingrenderer.h" />
   </ItemGroup>
   <ItemGroup>
     <Filter Include="ui">

tools/msvc/libs.vcxproj

@@ -211,20 +211,24 @@
     <ClInclude Include="..\..\libs\render\CamRenderer.h" />
     <ClInclude Include="..\..\libs\render\Colour4.h" />
     <ClInclude Include="..\..\libs\render\Colour4b.h" />
+    <ClInclude Include="..\..\libs\render\CompactWindingVertexBuffer.h" />
+    <ClInclude Include="..\..\libs\render\IndexedVertexBuffer.h" />
     <ClInclude Include="..\..\libs\render\NopVolumeTest.h" />
     <ClInclude Include="..\..\libs\render\RenderableCollectionWalker.h" />
     <ClInclude Include="..\..\libs\render\RenderablePivot.h" />
     <ClInclude Include="..\..\libs\render\RenderableSpacePartition.h" />
     <ClInclude Include="..\..\libs\render\SceneRenderWalker.h" />
     <ClInclude Include="..\..\libs\render\TexCoord2f.h" />
     <ClInclude Include="..\..\libs\render\TextureToolView.h" />
+    <ClInclude Include="..\..\libs\render\VBO.h" />
     <ClInclude Include="..\..\libs\render\VectorLightList.h" />
     <ClInclude Include="..\..\libs\render\Vertex3f.h" />
     <ClInclude Include="..\..\libs\render\VertexCb.h" />
     <ClInclude Include="..\..\libs\render\VertexHashing.h" />
     <ClInclude Include="..\..\libs\render\VertexNCb.h" />
     <ClInclude Include="..\..\libs\render\VertexNT.h" />
     <ClInclude Include="..\..\libs\render\View.h" />
+    <ClInclude Include="..\..\libs\render\WindingRenderer.h" />
     <ClInclude Include="..\..\libs\RGBAImage.h" />
     <ClInclude Include="..\..\libs\scenelib.h" />
     <ClInclude Include="..\..\libs\selectionlib.h" />

tools/msvc/libs.vcxproj.filters

@@ -329,6 +329,18 @@
     <ClInclude Include="..\..\libs\messages\MapOperationMessage.h">
       <Filter>messages</Filter>
     </ClInclude>
+    <ClInclude Include="..\..\libs\render\WindingRenderer.h">
+      <Filter>render</Filter>
+    </ClInclude>
+    <ClInclude Include="..\..\libs\render\CompactWindingVertexBuffer.h">
+      <Filter>render</Filter>
+    </ClInclude>
+    <ClInclude Include="..\..\libs\render\VBO.h">
+      <Filter>render</Filter>
+    </ClInclude>
+    <ClInclude Include="..\..\libs\render\IndexedVertexBuffer.h">
+      <Filter>render</Filter>
+    </ClInclude>
   </ItemGroup>
   <ItemGroup>
     <Filter Include="util">