Introduction to 3D Game …ogramming with DirectX 12/Introduction-to-3D-Game-Programming-with-DirectX-12.ISO/Code.Textures/Chapter 7 Drawing in Direct3D Part II/Shapes/ShapesApp.cpp

C/C++ Source or Header | 2016-03-02 | 30.2 KB | 806 lines

//***************************************************************************************
// ShapesApp.cpp by Frank Luna (C) 2015 All Rights Reserved.
//
// Hold down '1' key to view scene in wireframe mode.
//***************************************************************************************

#include "../../Common/d3dApp.h"
#include "../../Common/MathHelper.h"
#include "../../Common/UploadBuffer.h"
#include "../../Common/GeometryGenerator.h"
#include "FrameResource.h"

using Microsoft::WRL::ComPtr;
using namespace DirectX;
using namespace DirectX::PackedVector;

const int gNumFrameResources = 3;

// Lightweight structure stores parameters to draw a shape.  This will
// vary from app-to-app.
struct RenderItem
{
    RenderItem() = default;

    // World matrix of the shape that describes the object's local space
    // relative to the world space, which defines the position, orientation,
    // and scale of the object in the world.
    XMFLOAT4X4 World = MathHelper::Identity4x4();

    // Dirty flag indicating the object data has changed and we need to update the constant buffer.
    // Because we have an object cbuffer for each FrameResource, we have to apply the
    // update to each FrameResource.  Thus, when we modify obect data we should set
    // NumFramesDirty = gNumFrameResources so that each frame resource gets the update.
    int NumFramesDirty = gNumFrameResources;

    // Index into GPU constant buffer corresponding to the ObjectCB for this render item.
    UINT ObjCBIndex = -1;

    MeshGeometry* Geo = nullptr;

    // Primitive topology.
    D3D12_PRIMITIVE_TOPOLOGY PrimitiveType = D3D_PRIMITIVE_TOPOLOGY_TRIANGLELIST;

    // DrawIndexedInstanced parameters.
    UINT IndexCount = 0;
    UINT StartIndexLocation = 0;
    int BaseVertexLocation = 0;
};

class ShapesApp : public D3DApp
{
public:
    ShapesApp(HINSTANCE hInstance);
    ShapesApp(const ShapesApp& rhs) = delete;
    ShapesApp& operator=(const ShapesApp& rhs) = delete;
    ~ShapesApp();

    virtual bool Initialize()override;

private:
    virtual void OnResize()override;
    virtual void Update(const GameTimer& gt)override;
    virtual void Draw(const GameTimer& gt)override;

    virtual void OnMouseDown(WPARAM btnState, int x, int y)override;
    virtual void OnMouseUp(WPARAM btnState, int x, int y)override;
    virtual void OnMouseMove(WPARAM btnState, int x, int y)override;

    void OnKeyboardInput(const GameTimer& gt);
    void UpdateCamera(const GameTimer& gt);
    void UpdateObjectCBs(const GameTimer& gt);
    void UpdateMainPassCB(const GameTimer& gt);

    void BuildDescriptorHeaps();
    void BuildConstantBufferViews();
    void BuildRootSignature();
    void BuildShadersAndInputLayout();
    void BuildShapeGeometry();
    void BuildPSOs();
    void BuildFrameResources();
    void BuildRenderItems();
    void DrawRenderItems(ID3D12GraphicsCommandList* cmdList, const std::vector<RenderItem*>& ritems);

private:

    std::vector<std::unique_ptr<FrameResource>> mFrameResources;
    FrameResource* mCurrFrameResource = nullptr;
    int mCurrFrameResourceIndex = 0;

    ComPtr<ID3D12RootSignature> mRootSignature = nullptr;
    ComPtr<ID3D12DescriptorHeap> mCbvHeap = nullptr;

    ComPtr<ID3D12DescriptorHeap> mSrvDescriptorHeap = nullptr;

    std::unordered_map<std::string, std::unique_ptr<MeshGeometry>> mGeometries;
    std::unordered_map<std::string, ComPtr<ID3DBlob>> mShaders;
    std::unordered_map<std::string, ComPtr<ID3D12PipelineState>> mPSOs;

    std::vector<D3D12_INPUT_ELEMENT_DESC> mInputLayout;

    // List of all the render items.
    std::vector<std::unique_ptr<RenderItem>> mAllRitems;

    // Render items divided by PSO.
    std::vector<RenderItem*> mOpaqueRitems;

    PassConstants mMainPassCB;

    UINT mPassCbvOffset = 0;

    bool mIsWireframe = false;

    XMFLOAT3 mEyePos = { 0.0f, 0.0f, 0.0f };
    XMFLOAT4X4 mView = MathHelper::Identity4x4();
    XMFLOAT4X4 mProj = MathHelper::Identity4x4();

    float mTheta = 1.5f*XM_PI;
    float mPhi = 0.2f*XM_PI;
    float mRadius = 15.0f;

    POINT mLastMousePos;
};

int WINAPI WinMain(HINSTANCE hInstance, HINSTANCE prevInstance,
    PSTR cmdLine, int showCmd)
{
    // Enable run-time memory check for debug builds.
#if defined(DEBUG) | defined(_DEBUG)
    _CrtSetDbgFlag(_CRTDBG_ALLOC_MEM_DF | _CRTDBG_LEAK_CHECK_DF);
#endif

    try
    {
        ShapesApp theApp(hInstance);
        if(!theApp.Initialize())
            return 0;

        return theApp.Run();
    }
    catch(DxException& e)
    {
        MessageBox(nullptr, e.ToString().c_str(), L"HR Failed", MB_OK);
        return 0;
    }
}

ShapesApp::ShapesApp(HINSTANCE hInstance)
    : D3DApp(hInstance)
{
}

ShapesApp::~ShapesApp()
{
    if(md3dDevice != nullptr)
        FlushCommandQueue();
}

bool ShapesApp::Initialize()
{
    if(!D3DApp::Initialize())
        return false;

    // Reset the command list to prep for initialization commands.
    ThrowIfFailed(mCommandList->Reset(mDirectCmdListAlloc.Get(), nullptr));

    BuildRootSignature();
    BuildShadersAndInputLayout();
    BuildShapeGeometry();
    BuildRenderItems();
    BuildFrameResources();
    BuildDescriptorHeaps();
    BuildConstantBufferViews();
    BuildPSOs();

    // Execute the initialization commands.
    ThrowIfFailed(mCommandList->Close());
    ID3D12CommandList* cmdsLists[] = { mCommandList.Get() };
    mCommandQueue->ExecuteCommandLists(_countof(cmdsLists), cmdsLists);

    // Wait until initialization is complete.
    FlushCommandQueue();

    return true;
}

void ShapesApp::OnResize()
{
    D3DApp::OnResize();

    // The window resized, so update the aspect ratio and recompute the projection matrix.
    XMMATRIX P = XMMatrixPerspectiveFovLH(0.25f*MathHelper::Pi, AspectRatio(), 1.0f, 1000.0f);
    XMStoreFloat4x4(&mProj, P);
}

void ShapesApp::Update(const GameTimer& gt)
{
    OnKeyboardInput(gt);
    UpdateCamera(gt);

    // Cycle through the circular frame resource array.
    mCurrFrameResourceIndex = (mCurrFrameResourceIndex + 1) % gNumFrameResources;
    mCurrFrameResource = mFrameResources[mCurrFrameResourceIndex].get();

    // Has the GPU finished processing the commands of the current frame resource?
    // If not, wait until the GPU has completed commands up to this fence point.
    if(mCurrFrameResource->Fence != 0 && mFence->GetCompletedValue() < mCurrFrameResource->Fence)
    {
        HANDLE eventHandle = CreateEventEx(nullptr, false, false, EVENT_ALL_ACCESS);
        ThrowIfFailed(mFence->SetEventOnCompletion(mCurrFrameResource->Fence, eventHandle));
        WaitForSingleObject(eventHandle, INFINITE);
        CloseHandle(eventHandle);
    }

    UpdateObjectCBs(gt);
    UpdateMainPassCB(gt);
}

void ShapesApp::Draw(const GameTimer& gt)
{
    auto cmdListAlloc = mCurrFrameResource->CmdListAlloc;

    // Reuse the memory associated with command recording.
    // We can only reset when the associated command lists have finished execution on the GPU.
    ThrowIfFailed(cmdListAlloc->Reset());

    // A command list can be reset after it has been added to the command queue via ExecuteCommandList.
    // Reusing the command list reuses memory.
    if(mIsWireframe)
    {
        ThrowIfFailed(mCommandList->Reset(cmdListAlloc.Get(), mPSOs["opaque_wireframe"].Get()));
    }
    else
    {
        ThrowIfFailed(mCommandList->Reset(cmdListAlloc.Get(), mPSOs["opaque"].Get()));
    }

    mCommandList->RSSetViewports(1, &mScreenViewport);
    mCommandList->RSSetScissorRects(1, &mScissorRect);

    // Indicate a state transition on the resource usage.
    mCommandList->ResourceBarrier(1, &CD3DX12_RESOURCE_BARRIER::Transition(CurrentBackBuffer(),
        D3D12_RESOURCE_STATE_PRESENT, D3D12_RESOURCE_STATE_RENDER_TARGET));

    // Clear the back buffer and depth buffer.
    mCommandList->ClearRenderTargetView(CurrentBackBufferView(), Colors::LightSteelBlue, 0, nullptr);
    mCommandList->ClearDepthStencilView(DepthStencilView(), D3D12_CLEAR_FLAG_DEPTH | D3D12_CLEAR_FLAG_STENCIL, 1.0f, 0, 0, nullptr);

    // Specify the buffers we are going to render to.
    mCommandList->OMSetRenderTargets(1, &CurrentBackBufferView(), true, &DepthStencilView());

    ID3D12DescriptorHeap* descriptorHeaps[] = { mCbvHeap.Get() };
    mCommandList->SetDescriptorHeaps(_countof(descriptorHeaps), descriptorHeaps);

    mCommandList->SetGraphicsRootSignature(mRootSignature.Get());

    int passCbvIndex = mPassCbvOffset + mCurrFrameResourceIndex;
    auto passCbvHandle = CD3DX12_GPU_DESCRIPTOR_HANDLE(mCbvHeap->GetGPUDescriptorHandleForHeapStart());
    passCbvHandle.Offset(passCbvIndex, mCbvSrvUavDescriptorSize);
    mCommandList->SetGraphicsRootDescriptorTable(1, passCbvHandle);

    DrawRenderItems(mCommandList.Get(), mOpaqueRitems);

    // Indicate a state transition on the resource usage.
    mCommandList->ResourceBarrier(1, &CD3DX12_RESOURCE_BARRIER::Transition(CurrentBackBuffer(),
        D3D12_RESOURCE_STATE_RENDER_TARGET, D3D12_RESOURCE_STATE_PRESENT));

    // Done recording commands.
    ThrowIfFailed(mCommandList->Close());

    // Add the command list to the queue for execution.
    ID3D12CommandList* cmdsLists[] = { mCommandList.Get() };
    mCommandQueue->ExecuteCommandLists(_countof(cmdsLists), cmdsLists);

    // Swap the back and front buffers
    ThrowIfFailed(mSwapChain->Present(0, 0));
    mCurrBackBuffer = (mCurrBackBuffer + 1) % SwapChainBufferCount;

    // Advance the fence value to mark commands up to this fence point.
    mCurrFrameResource->Fence = ++mCurrentFence;

    // Add an instruction to the command queue to set a new fence point.
    // Because we are on the GPU timeline, the new fence point won't be
    // set until the GPU finishes processing all the commands prior to this Signal().
    mCommandQueue->Signal(mFence.Get(), mCurrentFence);
}

void ShapesApp::OnMouseDown(WPARAM btnState, int x, int y)
{
    mLastMousePos.x = x;
    mLastMousePos.y = y;

    SetCapture(mhMainWnd);
}

void ShapesApp::OnMouseUp(WPARAM btnState, int x, int y)
{
    ReleaseCapture();
}

void ShapesApp::OnMouseMove(WPARAM btnState, int x, int y)
{
    if((btnState & MK_LBUTTON) != 0)
    {
        // Make each pixel correspond to a quarter of a degree.
        float dx = XMConvertToRadians(0.25f*static_cast<float>(x - mLastMousePos.x));
        float dy = XMConvertToRadians(0.25f*static_cast<float>(y - mLastMousePos.y));

        // Update angles based on input to orbit camera around box.
        mTheta += dx;
        mPhi += dy;

        // Restrict the angle mPhi.
        mPhi = MathHelper::Clamp(mPhi, 0.1f, MathHelper::Pi - 0.1f);
    }
    else if((btnState & MK_RBUTTON) != 0)
    {
        // Make each pixel correspond to 0.2 unit in the scene.
        float dx = 0.05f*static_cast<float>(x - mLastMousePos.x);
        float dy = 0.05f*static_cast<float>(y - mLastMousePos.y);

        // Update the camera radius based on input.
        mRadius += dx - dy;

        // Restrict the radius.
        mRadius = MathHelper::Clamp(mRadius, 5.0f, 150.0f);
    }

    mLastMousePos.x = x;
    mLastMousePos.y = y;
}

void ShapesApp::OnKeyboardInput(const GameTimer& gt)
{
    if(GetAsyncKeyState('1') & 0x8000)
        mIsWireframe = true;
    else
        mIsWireframe = false;
}

void ShapesApp::UpdateCamera(const GameTimer& gt)
{
    // Convert Spherical to Cartesian coordinates.
    mEyePos.x = mRadius*sinf(mPhi)*cosf(mTheta);
    mEyePos.z = mRadius*sinf(mPhi)*sinf(mTheta);
    mEyePos.y = mRadius*cosf(mPhi);

    // Build the view matrix.
    XMVECTOR pos = XMVectorSet(mEyePos.x, mEyePos.y, mEyePos.z, 1.0f);
    XMVECTOR target = XMVectorZero();
    XMVECTOR up = XMVectorSet(0.0f, 1.0f, 0.0f, 0.0f);

    XMMATRIX view = XMMatrixLookAtLH(pos, target, up);
    XMStoreFloat4x4(&mView, view);
}

void ShapesApp::UpdateObjectCBs(const GameTimer& gt)
{
    auto currObjectCB = mCurrFrameResource->ObjectCB.get();
    for(auto& e : mAllRitems)
    {
        // Only update the cbuffer data if the constants have changed.
        // This needs to be tracked per frame resource.
        if(e->NumFramesDirty > 0)
        {
            XMMATRIX world = XMLoadFloat4x4(&e->World);

            ObjectConstants objConstants;
            XMStoreFloat4x4(&objConstants.World, XMMatrixTranspose(world));

            currObjectCB->CopyData(e->ObjCBIndex, objConstants);

            // Next FrameResource need to be updated too.
            e->NumFramesDirty--;
        }
    }
}

void ShapesApp::UpdateMainPassCB(const GameTimer& gt)
{
    XMMATRIX view = XMLoadFloat4x4(&mView);
    XMMATRIX proj = XMLoadFloat4x4(&mProj);

    XMMATRIX viewProj = XMMatrixMultiply(view, proj);
    XMMATRIX invView = XMMatrixInverse(&XMMatrixDeterminant(view), view);
    XMMATRIX invProj = XMMatrixInverse(&XMMatrixDeterminant(proj), proj);
    XMMATRIX invViewProj = XMMatrixInverse(&XMMatrixDeterminant(viewProj), viewProj);

    XMStoreFloat4x4(&mMainPassCB.View, XMMatrixTranspose(view));
    XMStoreFloat4x4(&mMainPassCB.InvView, XMMatrixTranspose(invView));
    XMStoreFloat4x4(&mMainPassCB.Proj, XMMatrixTranspose(proj));
    XMStoreFloat4x4(&mMainPassCB.InvProj, XMMatrixTranspose(invProj));
    XMStoreFloat4x4(&mMainPassCB.ViewProj, XMMatrixTranspose(viewProj));
    XMStoreFloat4x4(&mMainPassCB.InvViewProj, XMMatrixTranspose(invViewProj));
    mMainPassCB.EyePosW = mEyePos;
    mMainPassCB.RenderTargetSize = XMFLOAT2((float)mClientWidth, (float)mClientHeight);
    mMainPassCB.InvRenderTargetSize = XMFLOAT2(1.0f / mClientWidth, 1.0f / mClientHeight);
    mMainPassCB.NearZ = 1.0f;
    mMainPassCB.FarZ = 1000.0f;
    mMainPassCB.TotalTime = gt.TotalTime();
    mMainPassCB.DeltaTime = gt.DeltaTime();

    auto currPassCB = mCurrFrameResource->PassCB.get();
    currPassCB->CopyData(0, mMainPassCB);
}

void ShapesApp::BuildDescriptorHeaps()
{
    UINT objCount = (UINT)mOpaqueRitems.size();

    // Need a CBV descriptor for each object for each frame resource,
    // +1 for the perPass CBV for each frame resource.
    UINT numDescriptors = (objCount+1) * gNumFrameResources;

    // Save an offset to the start of the pass CBVs.  These are the last 3 descriptors.
    mPassCbvOffset = objCount * gNumFrameResources;

    D3D12_DESCRIPTOR_HEAP_DESC cbvHeapDesc;
    cbvHeapDesc.NumDescriptors = numDescriptors;
    cbvHeapDesc.Type = D3D12_DESCRIPTOR_HEAP_TYPE_CBV_SRV_UAV;
    cbvHeapDesc.Flags = D3D12_DESCRIPTOR_HEAP_FLAG_SHADER_VISIBLE;
    cbvHeapDesc.NodeMask = 0;
    ThrowIfFailed(md3dDevice->CreateDescriptorHeap(&cbvHeapDesc,
        IID_PPV_ARGS(&mCbvHeap)));
}

void ShapesApp::BuildConstantBufferViews()
{
    UINT objCBByteSize = d3dUtil::CalcConstantBufferByteSize(sizeof(ObjectConstants));

    UINT objCount = (UINT)mOpaqueRitems.size();

    // Need a CBV descriptor for each object for each frame resource.
    for(int frameIndex = 0; frameIndex < gNumFrameResources; ++frameIndex)
    {
        auto objectCB = mFrameResources[frameIndex]->ObjectCB->Resource();
        for(UINT i = 0; i < objCount; ++i)
        {
            D3D12_GPU_VIRTUAL_ADDRESS cbAddress = objectCB->GetGPUVirtualAddress();

            // Offset to the ith object constant buffer in the buffer.
            cbAddress += i*objCBByteSize;

            // Offset to the object cbv in the descriptor heap.
            int heapIndex = frameIndex*objCount + i;
            auto handle = CD3DX12_CPU_DESCRIPTOR_HANDLE(mCbvHeap->GetCPUDescriptorHandleForHeapStart());
            handle.Offset(heapIndex, mCbvSrvUavDescriptorSize);

            D3D12_CONSTANT_BUFFER_VIEW_DESC cbvDesc;
            cbvDesc.BufferLocation = cbAddress;
            cbvDesc.SizeInBytes = objCBByteSize;

            md3dDevice->CreateConstantBufferView(&cbvDesc, handle);
        }
    }

    UINT passCBByteSize = d3dUtil::CalcConstantBufferByteSize(sizeof(PassConstants));

    // Last three descriptors are the pass CBVs for each frame resource.
    for(int frameIndex = 0; frameIndex < gNumFrameResources; ++frameIndex)
    {
        auto passCB = mFrameResources[frameIndex]->PassCB->Resource();
        D3D12_GPU_VIRTUAL_ADDRESS cbAddress = passCB->GetGPUVirtualAddress();

        // Offset to the pass cbv in the descriptor heap.
        int heapIndex = mPassCbvOffset + frameIndex;
        auto handle = CD3DX12_CPU_DESCRIPTOR_HANDLE(mCbvHeap->GetCPUDescriptorHandleForHeapStart());
        handle.Offset(heapIndex, mCbvSrvUavDescriptorSize);

        D3D12_CONSTANT_BUFFER_VIEW_DESC cbvDesc;
        cbvDesc.BufferLocation = cbAddress;
        cbvDesc.SizeInBytes = passCBByteSize;

        md3dDevice->CreateConstantBufferView(&cbvDesc, handle);
    }
}

void ShapesApp::BuildRootSignature()
{
    CD3DX12_DESCRIPTOR_RANGE cbvTable0;
    cbvTable0.Init(D3D12_DESCRIPTOR_RANGE_TYPE_CBV, 1, 0);

    CD3DX12_DESCRIPTOR_RANGE cbvTable1;
    cbvTable1.Init(D3D12_DESCRIPTOR_RANGE_TYPE_CBV, 1, 1);

    // Root parameter can be a table, root descriptor or root constants.
    CD3DX12_ROOT_PARAMETER slotRootParameter[2];

    // Create root CBVs.
    slotRootParameter[0].InitAsDescriptorTable(1, &cbvTable0);
    slotRootParameter[1].InitAsDescriptorTable(1, &cbvTable1);

    // A root signature is an array of root parameters.
    CD3DX12_ROOT_SIGNATURE_DESC rootSigDesc(2, slotRootParameter, 0, nullptr,
        D3D12_ROOT_SIGNATURE_FLAG_ALLOW_INPUT_ASSEMBLER_INPUT_LAYOUT);

    // create a root signature with a single slot which points to a descriptor range consisting of a single constant buffer
    ComPtr<ID3DBlob> serializedRootSig = nullptr;
    ComPtr<ID3DBlob> errorBlob = nullptr;
    HRESULT hr = D3D12SerializeRootSignature(&rootSigDesc, D3D_ROOT_SIGNATURE_VERSION_1,
        serializedRootSig.GetAddressOf(), errorBlob.GetAddressOf());

    if(errorBlob != nullptr)
    {
        ::OutputDebugStringA((char*)errorBlob->GetBufferPointer());
    }
    ThrowIfFailed(hr);

    ThrowIfFailed(md3dDevice->CreateRootSignature(
        0,
        serializedRootSig->GetBufferPointer(),
        serializedRootSig->GetBufferSize(),
        IID_PPV_ARGS(mRootSignature.GetAddressOf())));
}

void ShapesApp::BuildShadersAndInputLayout()
{
    mShaders["standardVS"] = d3dUtil::CompileShader(L"Shaders\\color.hlsl", nullptr, "VS", "vs_5_1");
    mShaders["opaquePS"] = d3dUtil::CompileShader(L"Shaders\\color.hlsl", nullptr, "PS", "ps_5_1");

    mInputLayout =
    {
        { "POSITION", 0, DXGI_FORMAT_R32G32B32_FLOAT, 0, 0, D3D12_INPUT_CLASSIFICATION_PER_VERTEX_DATA, 0 },
        { "COLOR", 0, DXGI_FORMAT_R32G32B32A32_FLOAT, 0, 12, D3D12_INPUT_CLASSIFICATION_PER_VERTEX_DATA, 0 },
    };
}

void ShapesApp::BuildShapeGeometry()
{
    GeometryGenerator geoGen;
    GeometryGenerator::MeshData box = geoGen.CreateBox(1.5f, 0.5f, 1.5f, 3);
    GeometryGenerator::MeshData grid = geoGen.CreateGrid(20.0f, 30.0f, 60, 40);
    GeometryGenerator::MeshData sphere = geoGen.CreateSphere(0.5f, 20, 20);
    GeometryGenerator::MeshData cylinder = geoGen.CreateCylinder(0.5f, 0.3f, 3.0f, 20, 20);

    //
    // We are concatenating all the geometry into one big vertex/index buffer.  So
    // define the regions in the buffer each submesh covers.
    //

    // Cache the vertex offsets to each object in the concatenated vertex buffer.
    UINT boxVertexOffset = 0;
    UINT gridVertexOffset = (UINT)box.Vertices.size();
    UINT sphereVertexOffset = gridVertexOffset + (UINT)grid.Vertices.size();
    UINT cylinderVertexOffset = sphereVertexOffset + (UINT)sphere.Vertices.size();

    // Cache the starting index for each object in the concatenated index buffer.
    UINT boxIndexOffset = 0;
    UINT gridIndexOffset = (UINT)box.Indices32.size();
    UINT sphereIndexOffset = gridIndexOffset + (UINT)grid.Indices32.size();
    UINT cylinderIndexOffset = sphereIndexOffset + (UINT)sphere.Indices32.size();

    // Define the SubmeshGeometry that cover different
    // regions of the vertex/index buffers.

    SubmeshGeometry boxSubmesh;
    boxSubmesh.IndexCount = (UINT)box.Indices32.size();
    boxSubmesh.StartIndexLocation = boxIndexOffset;
    boxSubmesh.BaseVertexLocation = boxVertexOffset;

    SubmeshGeometry gridSubmesh;
    gridSubmesh.IndexCount = (UINT)grid.Indices32.size();
    gridSubmesh.StartIndexLocation = gridIndexOffset;
    gridSubmesh.BaseVertexLocation = gridVertexOffset;

    SubmeshGeometry sphereSubmesh;
    sphereSubmesh.IndexCount = (UINT)sphere.Indices32.size();
    sphereSubmesh.StartIndexLocation = sphereIndexOffset;
    sphereSubmesh.BaseVertexLocation = sphereVertexOffset;

    SubmeshGeometry cylinderSubmesh;
    cylinderSubmesh.IndexCount = (UINT)cylinder.Indices32.size();
    cylinderSubmesh.StartIndexLocation = cylinderIndexOffset;
    cylinderSubmesh.BaseVertexLocation = cylinderVertexOffset;

    //
    // Extract the vertex elements we are interested in and pack the
    // vertices of all the meshes into one vertex buffer.
    //

    auto totalVertexCount =
        box.Vertices.size() +
        grid.Vertices.size() +
        sphere.Vertices.size() +
        cylinder.Vertices.size();

    std::vector<Vertex> vertices(totalVertexCount);

    UINT k = 0;
    for(size_t i = 0; i < box.Vertices.size(); ++i, ++k)
    {
        vertices[k].Pos = box.Vertices[i].Position;
        vertices[k].Color = XMFLOAT4(DirectX::Colors::DarkGreen);
    }

    for(size_t i = 0; i < grid.Vertices.size(); ++i, ++k)
    {
        vertices[k].Pos = grid.Vertices[i].Position;
        vertices[k].Color = XMFLOAT4(DirectX::Colors::ForestGreen);
    }

    for(size_t i = 0; i < sphere.Vertices.size(); ++i, ++k)
    {
        vertices[k].Pos = sphere.Vertices[i].Position;
        vertices[k].Color = XMFLOAT4(DirectX::Colors::Crimson);
    }

    for(size_t i = 0; i < cylinder.Vertices.size(); ++i, ++k)
    {
        vertices[k].Pos = cylinder.Vertices[i].Position;
        vertices[k].Color = XMFLOAT4(DirectX::Colors::SteelBlue);
    }

    std::vector<std::uint16_t> indices;
    indices.insert(indices.end(), std::begin(box.GetIndices16()), std::end(box.GetIndices16()));
    indices.insert(indices.end(), std::begin(grid.GetIndices16()), std::end(grid.GetIndices16()));
    indices.insert(indices.end(), std::begin(sphere.GetIndices16()), std::end(sphere.GetIndices16()));
    indices.insert(indices.end(), std::begin(cylinder.GetIndices16()), std::end(cylinder.GetIndices16()));

    const UINT vbByteSize = (UINT)vertices.size() * sizeof(Vertex);
    const UINT ibByteSize = (UINT)indices.size()  * sizeof(std::uint16_t);

    auto geo = std::make_unique<MeshGeometry>();
    geo->Name = "shapeGeo";

    ThrowIfFailed(D3DCreateBlob(vbByteSize, &geo->VertexBufferCPU));
    CopyMemory(geo->VertexBufferCPU->GetBufferPointer(), vertices.data(), vbByteSize);

    ThrowIfFailed(D3DCreateBlob(ibByteSize, &geo->IndexBufferCPU));
    CopyMemory(geo->IndexBufferCPU->GetBufferPointer(), indices.data(), ibByteSize);

    geo->VertexBufferGPU = d3dUtil::CreateDefaultBuffer(md3dDevice.Get(),
        mCommandList.Get(), vertices.data(), vbByteSize, geo->VertexBufferUploader);

    geo->IndexBufferGPU = d3dUtil::CreateDefaultBuffer(md3dDevice.Get(),
        mCommandList.Get(), indices.data(), ibByteSize, geo->IndexBufferUploader);

    geo->VertexByteStride = sizeof(Vertex);
    geo->VertexBufferByteSize = vbByteSize;
    geo->IndexFormat = DXGI_FORMAT_R16_UINT;
    geo->IndexBufferByteSize = ibByteSize;

    geo->DrawArgs["box"] = boxSubmesh;
    geo->DrawArgs["grid"] = gridSubmesh;
    geo->DrawArgs["sphere"] = sphereSubmesh;
    geo->DrawArgs["cylinder"] = cylinderSubmesh;

    mGeometries[geo->Name] = std::move(geo);
}

void ShapesApp::BuildPSOs()
{
    D3D12_GRAPHICS_PIPELINE_STATE_DESC opaquePsoDesc;

    //
    // PSO for opaque objects.
    //
    ZeroMemory(&opaquePsoDesc, sizeof(D3D12_GRAPHICS_PIPELINE_STATE_DESC));
    opaquePsoDesc.InputLayout = { mInputLayout.data(), (UINT)mInputLayout.size() };
    opaquePsoDesc.pRootSignature = mRootSignature.Get();
    opaquePsoDesc.VS =
    {
        reinterpret_cast<BYTE*>(mShaders["standardVS"]->GetBufferPointer()),
        mShaders["standardVS"]->GetBufferSize()
    };
    opaquePsoDesc.PS =
    {
        reinterpret_cast<BYTE*>(mShaders["opaquePS"]->GetBufferPointer()),
        mShaders["opaquePS"]->GetBufferSize()
    };
    opaquePsoDesc.RasterizerState = CD3DX12_RASTERIZER_DESC(D3D12_DEFAULT);
    opaquePsoDesc.RasterizerState.FillMode = D3D12_FILL_MODE_WIREFRAME;
    opaquePsoDesc.BlendState = CD3DX12_BLEND_DESC(D3D12_DEFAULT);
    opaquePsoDesc.DepthStencilState = CD3DX12_DEPTH_STENCIL_DESC(D3D12_DEFAULT);
    opaquePsoDesc.SampleMask = UINT_MAX;
    opaquePsoDesc.PrimitiveTopologyType = D3D12_PRIMITIVE_TOPOLOGY_TYPE_TRIANGLE;
    opaquePsoDesc.NumRenderTargets = 1;
    opaquePsoDesc.RTVFormats[0] = mBackBufferFormat;
    opaquePsoDesc.SampleDesc.Count = m4xMsaaState ? 4 : 1;
    opaquePsoDesc.SampleDesc.Quality = m4xMsaaState ? (m4xMsaaQuality - 1) : 0;
    opaquePsoDesc.DSVFormat = mDepthStencilFormat;
    ThrowIfFailed(md3dDevice->CreateGraphicsPipelineState(&opaquePsoDesc, IID_PPV_ARGS(&mPSOs["opaque"])));


    //
    // PSO for opaque wireframe objects.
    //

    D3D12_GRAPHICS_PIPELINE_STATE_DESC opaqueWireframePsoDesc = opaquePsoDesc;
    opaqueWireframePsoDesc.RasterizerState.FillMode = D3D12_FILL_MODE_WIREFRAME;
    ThrowIfFailed(md3dDevice->CreateGraphicsPipelineState(&opaqueWireframePsoDesc, IID_PPV_ARGS(&mPSOs["opaque_wireframe"])));
}

void ShapesApp::BuildFrameResources()
{
    for(int i = 0; i < gNumFrameResources; ++i)
    {
        mFrameResources.push_back(std::make_unique<FrameResource>(md3dDevice.Get(),
            1, (UINT)mAllRitems.size()));
    }
}

void ShapesApp::BuildRenderItems()
{
    auto boxRitem = std::make_unique<RenderItem>();
    XMStoreFloat4x4(&boxRitem->World, XMMatrixScaling(2.0f, 2.0f, 2.0f)*XMMatrixTranslation(0.0f, 0.5f, 0.0f));
    boxRitem->ObjCBIndex = 0;
    boxRitem->Geo = mGeometries["shapeGeo"].get();
    boxRitem->PrimitiveType = D3D_PRIMITIVE_TOPOLOGY_TRIANGLELIST;
    boxRitem->IndexCount = boxRitem->Geo->DrawArgs["box"].IndexCount;
    boxRitem->StartIndexLocation = boxRitem->Geo->DrawArgs["box"].StartIndexLocation;
    boxRitem->BaseVertexLocation = boxRitem->Geo->DrawArgs["box"].BaseVertexLocation;
    mAllRitems.push_back(std::move(boxRitem));

    auto gridRitem = std::make_unique<RenderItem>();
    gridRitem->World = MathHelper::Identity4x4();
    gridRitem->ObjCBIndex = 1;
    gridRitem->Geo = mGeometries["shapeGeo"].get();
    gridRitem->PrimitiveType = D3D_PRIMITIVE_TOPOLOGY_TRIANGLELIST;
    gridRitem->IndexCount = gridRitem->Geo->DrawArgs["grid"].IndexCount;
    gridRitem->StartIndexLocation = gridRitem->Geo->DrawArgs["grid"].StartIndexLocation;
    gridRitem->BaseVertexLocation = gridRitem->Geo->DrawArgs["grid"].BaseVertexLocation;
    mAllRitems.push_back(std::move(gridRitem));

    UINT objCBIndex = 2;
    for(int i = 0; i < 5; ++i)
    {
        auto leftCylRitem = std::make_unique<RenderItem>();
        auto rightCylRitem = std::make_unique<RenderItem>();
        auto leftSphereRitem = std::make_unique<RenderItem>();
        auto rightSphereRitem = std::make_unique<RenderItem>();

        XMMATRIX leftCylWorld = XMMatrixTranslation(-5.0f, 1.5f, -10.0f + i*5.0f);
        XMMATRIX rightCylWorld = XMMatrixTranslation(+5.0f, 1.5f, -10.0f + i*5.0f);

        XMMATRIX leftSphereWorld = XMMatrixTranslation(-5.0f, 3.5f, -10.0f + i*5.0f);
        XMMATRIX rightSphereWorld = XMMatrixTranslation(+5.0f, 3.5f, -10.0f + i*5.0f);

        XMStoreFloat4x4(&leftCylRitem->World, rightCylWorld);
        leftCylRitem->ObjCBIndex = objCBIndex++;
        leftCylRitem->Geo = mGeometries["shapeGeo"].get();
        leftCylRitem->PrimitiveType = D3D_PRIMITIVE_TOPOLOGY_TRIANGLELIST;
        leftCylRitem->IndexCount = leftCylRitem->Geo->DrawArgs["cylinder"].IndexCount;
        leftCylRitem->StartIndexLocation = leftCylRitem->Geo->DrawArgs["cylinder"].StartIndexLocation;
        leftCylRitem->BaseVertexLocation = leftCylRitem->Geo->DrawArgs["cylinder"].BaseVertexLocation;

        XMStoreFloat4x4(&rightCylRitem->World, leftCylWorld);
        rightCylRitem->ObjCBIndex = objCBIndex++;
        rightCylRitem->Geo = mGeometries["shapeGeo"].get();
        rightCylRitem->PrimitiveType = D3D_PRIMITIVE_TOPOLOGY_TRIANGLELIST;
        rightCylRitem->IndexCount = rightCylRitem->Geo->DrawArgs["cylinder"].IndexCount;
        rightCylRitem->StartIndexLocation = rightCylRitem->Geo->DrawArgs["cylinder"].StartIndexLocation;
        rightCylRitem->BaseVertexLocation = rightCylRitem->Geo->DrawArgs["cylinder"].BaseVertexLocation;

        XMStoreFloat4x4(&leftSphereRitem->World, leftSphereWorld);
        leftSphereRitem->ObjCBIndex = objCBIndex++;
        leftSphereRitem->Geo = mGeometries["shapeGeo"].get();
        leftSphereRitem->PrimitiveType = D3D_PRIMITIVE_TOPOLOGY_TRIANGLELIST;
        leftSphereRitem->IndexCount = leftSphereRitem->Geo->DrawArgs["sphere"].IndexCount;
        leftSphereRitem->StartIndexLocation = leftSphereRitem->Geo->DrawArgs["sphere"].StartIndexLocation;
        leftSphereRitem->BaseVertexLocation = leftSphereRitem->Geo->DrawArgs["sphere"].BaseVertexLocation;

        XMStoreFloat4x4(&rightSphereRitem->World, rightSphereWorld);
        rightSphereRitem->ObjCBIndex = objCBIndex++;
        rightSphereRitem->Geo = mGeometries["shapeGeo"].get();
        rightSphereRitem->PrimitiveType = D3D_PRIMITIVE_TOPOLOGY_TRIANGLELIST;
        rightSphereRitem->IndexCount = rightSphereRitem->Geo->DrawArgs["sphere"].IndexCount;
        rightSphereRitem->StartIndexLocation = rightSphereRitem->Geo->DrawArgs["sphere"].StartIndexLocation;
        rightSphereRitem->BaseVertexLocation = rightSphereRitem->Geo->DrawArgs["sphere"].BaseVertexLocation;

        mAllRitems.push_back(std::move(leftCylRitem));
        mAllRitems.push_back(std::move(rightCylRitem));
        mAllRitems.push_back(std::move(leftSphereRitem));
        mAllRitems.push_back(std::move(rightSphereRitem));
    }

    // All the render items are opaque.
    for(auto& e : mAllRitems)
        mOpaqueRitems.push_back(e.get());
}

void ShapesApp::DrawRenderItems(ID3D12GraphicsCommandList* cmdList, const std::vector<RenderItem*>& ritems)
{
    UINT objCBByteSize = d3dUtil::CalcConstantBufferByteSize(sizeof(ObjectConstants));

    auto objectCB = mCurrFrameResource->ObjectCB->Resource();

    // For each render item...
    for(size_t i = 0; i < ritems.size(); ++i)
    {
        auto ri = ritems[i];

        cmdList->IASetVertexBuffers(0, 1, &ri->Geo->VertexBufferView());
        cmdList->IASetIndexBuffer(&ri->Geo->IndexBufferView());
        cmdList->IASetPrimitiveTopology(ri->PrimitiveType);

        // Offset to the CBV in the descriptor heap for this object and for this frame resource.
        UINT cbvIndex = mCurrFrameResourceIndex*(UINT)mOpaqueRitems.size() + ri->ObjCBIndex;
        auto cbvHandle = CD3DX12_GPU_DESCRIPTOR_HANDLE(mCbvHeap->GetGPUDescriptorHandleForHeapStart());
        cbvHandle.Offset(cbvIndex, mCbvSrvUavDescriptorSize);

        cmdList->SetGraphicsRootDescriptorTable(0, cbvHandle);

        cmdList->DrawIndexedInstanced(ri->IndexCount, 1, ri->StartIndexLocation, ri->BaseVertexLocation, 0);
    }
}