1 files changed, 439 insertions, 0 deletions

diff --git a/hello/main.cc b/hello/main.cc
new file mode 100644
index 0000000..1b94cf6
--- /dev/null
+++ b/hello/main.cc
@@ -0,0 +1,439 @@
+#include <dxcommon.h>
+#include <dxwindow.h>
+
+#include <d3d12.h>
+#include <dxgi1_4.h>
+#include <directx/d3dx12.h>
+
+#include <cassert>
+#include <cstdio>
+
+using namespace dx;
+
+struct D3DSettings
+{
+    int width = 0;
+    int height = 0;
+};
+
+class D3D
+{
+public:
+    void Initialise(Window* window, const D3DSettings& settings)
+    {
+        m_window = window;
+        m_settings = settings;
+
+        UINT dxgiFactoryFlags = 0;
+#ifdef DEBUG
+        {
+            ComPtr<ID3D12Debug> debug;
+            D3D12GetDebugInterface(IID_PPV_ARGS(&debug));
+            debug->EnableDebugLayer();
+            dxgiFactoryFlags |= DXGI_CREATE_FACTORY_DEBUG;
+        }
+#endif
+        ThrowIfFailed(CreateDXGIFactory2(
+            dxgiFactoryFlags, IID_PPV_ARGS(&m_dxgi_factory)));
+
+        // Prevent Alt+Enter from going into fullscreen.
+        ThrowIfFailed(m_dxgi_factory->MakeWindowAssociation(
+            m_window->GetWindowHandle(),
+            DXGI_MWA_NO_ALT_ENTER));
+
+        ThrowIfFailed(D3D12CreateDevice(
+            /*pAdapter=*/nullptr, // Default adapter.
+            D3D_FEATURE_LEVEL_11_0,
+            IID_PPV_ARGS(&m_device)));
+
+        m_rtv_descriptor_size = m_device->GetDescriptorHandleIncrementSize(
+            D3D12_DESCRIPTOR_HEAP_TYPE_RTV);
+        m_dsv_descriptor_size = m_device->GetDescriptorHandleIncrementSize(
+            D3D12_DESCRIPTOR_HEAP_TYPE_DSV);
+        m_cbv_descriptor_size = m_device->GetDescriptorHandleIncrementSize(
+            D3D12_DESCRIPTOR_HEAP_TYPE_CBV_SRV_UAV);
+
+        const D3D12_COMMAND_QUEUE_DESC queue_desc =
+        {
+            .Type  = D3D12_COMMAND_LIST_TYPE_DIRECT,
+            .Flags = D3D12_COMMAND_QUEUE_FLAG_NONE,
+        };
+        ThrowIfFailed(m_device->CreateCommandQueue(
+            &queue_desc,
+            IID_PPV_ARGS(&m_command_queue)));
+
+        ThrowIfFailed(m_device->CreateCommandAllocator(
+            queue_desc.Type,
+            IID_PPV_ARGS(&m_command_allocator)));
+
+        // The command allocator is the memory backing for the command list.
+        // It is in the allocator's memory where the commands are stored.
+        ThrowIfFailed(m_device->CreateCommandList(
+            /*nodeMask=*/0,
+            queue_desc.Type,
+            m_command_allocator.Get(),
+            /*pInitialState=*/nullptr,  // Pipeline state.
+            IID_PPV_ARGS(&m_command_list)));
+
+        // Command lists are in the "open" state after they are created. It is
+        // easier to assume that they start in the "closed" state at each
+        // iteration of the main loop, however. The Reset() method, which we'll
+        // use later, also expects the command list to be closed.
+        ThrowIfFailed(m_command_list->Close());
+
+        CreateDescriptorHeaps();
+
+        CreateSwapChain();
+        CreateSwapChainBufferRenderTargetViews();
+        CreateDepthStencilBufferAndView();
+
+        ThrowIfFailed(m_device->CreateFence(
+            /*InitialValue=*/m_fence_value,
+            D3D12_FENCE_FLAG_NONE,
+            IID_PPV_ARGS(&m_fence)));
+
+        if ((m_fence_event = CreateEvent(
+            /*lpEventAttributes=*/nullptr,
+            /*bManualReset=*/FALSE,
+            /*bInitialState=*/FALSE,
+            /*lpName=*/nullptr)) == 0)
+        {
+            ThrowIfFailed(HRESULT_FROM_WIN32(GetLastError()));
+        }
+    }
+
+    void Render()
+    {
+        PopulateCommandList();
+
+        ID3D12CommandList* command_lists[] = { m_command_list.Get() };
+        m_command_queue->ExecuteCommandLists(
+            _countof(command_lists), command_lists);
+
+        ThrowIfFailed(m_swap_chain->Present(/*SyncInterval=*/1, /*Flags=*/0));
+        m_current_back_buffer = m_swap_chain->GetCurrentBackBufferIndex();
+
+        // It is not efficient to wait for the frame to complete here, but it
+        // is simple and sufficient for this application.
+        WaitForPreviousFrame();
+    }
+
+private:
+    void PopulateCommandList()
+    {
+        /// Note that we skip the following two items:
+        ///
+        ///   1. RSSetViewports()
+        ///   2. OMSetRenderTargets()
+        ///
+        /// This application does not render anything useful, it simply clears
+        /// the back buffer and depth/stencil view. Clearing both resources
+        /// does not require a viewport to be set or the OM (output-merger
+        /// stage) to be configured.
+
+        // A command allocator can only be reset when its associated command
+        // lists are finished executing on the GPU. This requires
+        // synchronisation.
+        ThrowIfFailed(m_command_allocator->Reset());
+
+        // A command list can be reset as soon as it is executed with
+        // ExecuteCommandList(). Reset() does require that the command list is
+        // in a "closed" state, however, which is why we close it right away
+        // after creation.
+        ThrowIfFailed(m_command_list->Reset(
+            m_command_allocator.Get(),
+            /*pInitialState=*/nullptr));
+
+        // Indicate that we intend to use the back buffer as a render target.
+        const auto render_barrier = CD3DX12_RESOURCE_BARRIER::Transition(
+            GetCurrentBackBuffer(),
+            D3D12_RESOURCE_STATE_PRESENT,
+            D3D12_RESOURCE_STATE_RENDER_TARGET);
+        m_command_list->ResourceBarrier(1, &render_barrier);
+
+        // Record commands.
+        const float clear_colour[] = { 0.0f, 0.0f, 0.0f, 0.0f };
+        m_command_list->ClearRenderTargetView(
+            GetCurrentBackBufferView(),
+            clear_colour,
+            0,         // Number of rectangles in the following array.
+            nullptr);  // No rectangles; clear the entire resource.
+
+        m_command_list->ClearDepthStencilView(
+            GetDepthStencilView(),
+            D3D12_CLEAR_FLAG_DEPTH | D3D12_CLEAR_FLAG_STENCIL,
+            1.0f,      // Depth.
+            0,         // Stencil.
+            0,         // Number of rectangles in the following array.
+            nullptr);  // No rectangles; clear the entire resource view.
+
+        // Indicate that we now intend to use the back buffer to present.
+        const auto present_barrier = CD3DX12_RESOURCE_BARRIER::Transition(
+            GetCurrentBackBuffer(),
+            D3D12_RESOURCE_STATE_RENDER_TARGET,
+            D3D12_RESOURCE_STATE_PRESENT);
+        m_command_list->ResourceBarrier(1, &present_barrier);
+
+        ThrowIfFailed(m_command_list->Close());
+    }
+
+    void WaitForPreviousFrame()
+    {
+        // Advance the fence value to mark commands up to this fence point.
+        m_fence_value++;
+
+        // The command queue will signal the new fence value when all commands
+        // up to this point have finished execution.
+        ThrowIfFailed(m_command_queue->Signal(m_fence.Get(), m_fence_value));
+
+        // Wait for commands to finish execution.
+        // It is possible that execution has already finished by the time we
+        // get here, so first check the fence's completed value.
+        if (m_fence->GetCompletedValue() < m_fence_value)
+        {
+            // Commands are still being executed. Configure a Windows event
+            // and wait for it. The event fires when the commands have finished
+            // execution.
+
+            // Indicate that |m_fence_event| is to be fired when |m_fence|
+            // reaches the |fence| value.
+            ThrowIfFailed(m_fence->SetEventOnCompletion(
+                m_fence_value, m_fence_event));
+
+            WaitForSingleObject(m_fence_event, INFINITE);
+        }
+    }
+
+    /// Creates RTV and DSV descriptor heaps.
+    void CreateDescriptorHeaps()
+    {
+        assert(m_device);
+
+        // The RTV heap must hold as many descriptors as we have buffers in the
+        // swap chain.
+        const D3D12_DESCRIPTOR_HEAP_DESC rtv_heap_desc =
+        {
+            .Type = D3D12_DESCRIPTOR_HEAP_TYPE_RTV,
+            .NumDescriptors = SWAP_CHAIN_BUFFER_COUNT,
+            .Flags = D3D12_DESCRIPTOR_HEAP_FLAG_NONE,
+            .NodeMask = 0,
+        };
+        ThrowIfFailed(m_device->CreateDescriptorHeap(
+            &rtv_heap_desc, IID_PPV_ARGS(&m_rtv_heap)));
+
+        // For the depth/stencil buffer, we just need one view.
+        const D3D12_DESCRIPTOR_HEAP_DESC dsv_heap_desc =
+        {
+            .Type = D3D12_DESCRIPTOR_HEAP_TYPE_DSV,
+            .NumDescriptors = 1,
+            .Flags = D3D12_DESCRIPTOR_HEAP_FLAG_NONE,
+            .NodeMask = 0,
+        };
+        ThrowIfFailed(m_device->CreateDescriptorHeap(
+            &dsv_heap_desc, IID_PPV_ARGS(&m_dsv_heap)));
+    }
+
+    /// Creates the application's swap chain.
+    ///
+    /// This method can be called multiple times to re-create the swap chain.
+    void CreateSwapChain()
+    {
+        assert(m_dxgi_factory);
+        assert(m_command_queue);
+
+        SafeRelease(m_swap_chain);
+
+        DXGI_SWAP_CHAIN_DESC1 desc =
+        {
+            .Width  = static_cast<UINT>(m_settings.width),
+            .Height = static_cast<UINT>(m_settings.height),
+            .Format = DXGI_FORMAT_R8G8B8A8_UNORM,
+            .SampleDesc = DXGI_SAMPLE_DESC
+            {
+                .Count = 1,
+                .Quality = 0,
+            },
+            .BufferUsage = DXGI_USAGE_RENDER_TARGET_OUTPUT,
+            .BufferCount = SWAP_CHAIN_BUFFER_COUNT,
+            .SwapEffect = DXGI_SWAP_EFFECT_FLIP_DISCARD,
+        };
+        ComPtr<IDXGISwapChain1> swap_chain;
+        ThrowIfFailed(m_dxgi_factory->CreateSwapChainForHwnd(
+            m_command_queue.Get(),  // Swap chain uses queue to perform flush.
+            m_window->GetWindowHandle(),
+            &desc,
+            /*pFullScreenDesc=*/nullptr,  // Running in windowed mode.
+            /*pRestrictToOutput=*/nullptr,
+            &swap_chain));
+        ThrowIfFailed(swap_chain.As(&m_swap_chain));
+
+        m_current_back_buffer = m_swap_chain->GetCurrentBackBufferIndex();
+    }
+
+    /// Creates RTVs for all of the swap chain's buffers.
+    void CreateSwapChainBufferRenderTargetViews()
+    {
+        assert(m_device);
+        assert(m_swap_chain);
+        assert(m_rtv_heap);
+
+        // Create the new buffer views.
+        CD3DX12_CPU_DESCRIPTOR_HANDLE rtv_heap_handle(
+            m_rtv_heap->GetCPUDescriptorHandleForHeapStart());
+        for (int i = 0; i < SWAP_CHAIN_BUFFER_COUNT; ++i)
+        {
+            ThrowIfFailed(m_swap_chain->GetBuffer(
+                i, IID_PPV_ARGS(&m_swap_chain_buffer[i])));
+
+            m_device->CreateRenderTargetView(
+                m_swap_chain_buffer[i].Get(), /*pDesc=*/nullptr, rtv_heap_handle);
+
+            rtv_heap_handle.Offset(1, m_rtv_descriptor_size);
+        }
+    }
+
+    /// Creates a depth/stencil buffer and its view.
+    void CreateDepthStencilBufferAndView()
+    {
+        assert(m_device);
+
+        const D3D12_RESOURCE_DESC depth_stencil_desc =
+        {
+            .Dimension = D3D12_RESOURCE_DIMENSION_TEXTURE2D,
+            .Alignment = 0,
+            .Width = static_cast<UINT64>(m_settings.width),
+            .Height = static_cast<UINT>(m_settings.height),
+            .DepthOrArraySize = 1,
+            .MipLevels = 1,
+            .Format = DXGI_FORMAT_D24_UNORM_S8_UINT,
+            .SampleDesc = DXGI_SAMPLE_DESC
+            {
+                .Count = 1,
+                .Quality = 0,
+            },
+            .Layout = D3D12_TEXTURE_LAYOUT_UNKNOWN,
+            .Flags = D3D12_RESOURCE_FLAG_ALLOW_DEPTH_STENCIL,
+        };
+        const D3D12_CLEAR_VALUE opt_clear_value =
+        {
+            .Format = depth_stencil_desc.Format,
+            .DepthStencil = D3D12_DEPTH_STENCIL_VALUE
+            {
+                .Depth = 1.0f,
+                .Stencil = 0,
+            },
+        };
+        const CD3DX12_HEAP_PROPERTIES depth_stencil_heap_properties(
+            D3D12_HEAP_TYPE_DEFAULT);
+        ThrowIfFailed(m_device->CreateCommittedResource(
+            &depth_stencil_heap_properties,
+            D3D12_HEAP_FLAG_NONE,
+            &depth_stencil_desc,
+            D3D12_RESOURCE_STATE_COMMON,
+            &opt_clear_value,
+            IID_PPV_ARGS(&m_depth_stencil_buffer)));
+
+        m_device->CreateDepthStencilView(
+            m_depth_stencil_buffer.Get(),
+            /*pDesc=*/nullptr,
+            GetDepthStencilView());
+    }
+
+    ID3D12Resource* GetCurrentBackBuffer() const
+    {
+        return m_swap_chain_buffer[m_current_back_buffer].Get();
+    }
+
+    D3D12_CPU_DESCRIPTOR_HANDLE GetCurrentBackBufferView() const
+    {
+        assert(m_rtv_heap);
+        assert(m_rtv_descriptor_size > 0);
+        return CD3DX12_CPU_DESCRIPTOR_HANDLE(
+            m_rtv_heap->GetCPUDescriptorHandleForHeapStart(),
+            m_current_back_buffer,
+            m_rtv_descriptor_size);
+    }
+
+    D3D12_CPU_DESCRIPTOR_HANDLE GetDepthStencilView() const
+    {
+        assert(m_dsv_heap);
+        return m_dsv_heap->GetCPUDescriptorHandleForHeapStart();
+    }
+
+private:
+    static constexpr int SWAP_CHAIN_BUFFER_COUNT = 2;  // Double-buffering.
+
+    Window* m_window = nullptr;
+    D3DSettings m_settings;
+
+    ComPtr<IDXGIFactory4> m_dxgi_factory;
+    ComPtr<ID3D12Device> m_device;
+
+    ComPtr<ID3D12CommandQueue> m_command_queue;
+    ComPtr<ID3D12CommandAllocator> m_command_allocator;
+    ComPtr<ID3D12GraphicsCommandList> m_command_list;
+
+    ComPtr<IDXGISwapChain3> m_swap_chain;
+
+    ComPtr<ID3D12DescriptorHeap> m_rtv_heap;
+    ComPtr<ID3D12DescriptorHeap> m_dsv_heap;
+
+    ComPtr<ID3D12Resource> m_swap_chain_buffer[SWAP_CHAIN_BUFFER_COUNT];
+    ComPtr<ID3D12Resource> m_depth_stencil_buffer;
+
+    ComPtr<ID3D12Fence> m_fence;
+    HANDLE m_fence_event = 0;
+    UINT64 m_fence_value = 0;
+
+    // Index to the buffer in the RTV descriptor heap that represents the
+    // current back buffer.
+    int m_current_back_buffer = 0;
+
+    UINT m_rtv_descriptor_size = 0;
+    UINT m_dsv_descriptor_size = 0;
+    UINT m_cbv_descriptor_size = 0;
+};
+
+int main()
+{
+    try
+    {
+        const D3DSettings settings =
+        {
+            // TODO: use 960x600 or 1920x1200 depending on native resolution.
+            .width = 1920,
+            .height = 1200,
+        };
+
+        if (!WindowInitialise())
+        {
+            THROW("Failed to initialise the window subsystem");
+        }
+        {
+            Window window;
+            if (!window.Initialise(
+                settings.width, settings.height, /*title=*/"D3D Application"))
+            {
+                THROW(GetWindowError());
+            }
+
+            D3D d3d;
+            d3d.Initialise(&window, settings);
+
+            while (!window.ShouldClose())
+            {
+                window.Update();
+                d3d.Render();
+                Sleep(10);
+            }
+        }
+        WindowTerminate();
+
+        return 0;
+    }
+    catch (const std::exception& e)
+    {
+        fprintf(stderr, "Exception caught: %s\n", e.what());
+        return 1;
+    }
+}