SimpleLighting12.h

//--------------------------------------------------------------------------------------
// SimpleLighting12.h
//
// Advanced Technology Group (ATG)
// Copyright (C) Microsoft Corporation. All rights reserved.
//--------------------------------------------------------------------------------------

#pragma once

#include "DeviceResources.h"
#include "StepTimer.h"


// A basic sample implementation that creates a D3D12 device and
// provides a render loop.
class Sample
{
public:

    Sample();

    // Initialization and management
    void Initialize(IUnknown* window);

    // Basic Sample loop
    void Tick();

    // Messages
    void OnSuspending();
    void OnResuming();

private:

	struct ConstantBuffer
	{
		DirectX::XMMATRIX worldMatrix;
		DirectX::XMMATRIX viewMatrix;
		DirectX::XMMATRIX projectionMatrix;
		DirectX::XMVECTOR lightDir[2];
		DirectX::XMVECTOR lightColor[2];
		DirectX::XMVECTOR outputColor;
	};

	// We'll allocate space for several of these and they will need to be padded for alignment.
	static_assert(sizeof(ConstantBuffer) == 272, "Checking the size here.");

	// D3D12_CONSTANT_BUFFER_DATA_PLACEMENT_ALIGNMENT < 272 < 2 * D3D12_CONSTANT_BUFFER_DATA_PLACEMENT_ALIGNMENT
	// Create a union with the correct size and enough room for one ConstantBuffer
	union PaddedConstantBuffer
	{
		ConstantBuffer constants;
		uint8_t bytes[2 * D3D12_CONSTANT_BUFFER_DATA_PLACEMENT_ALIGNMENT];
	};
	
	// Check the exact size of the PaddedConstantBuffer to make sure it will align properly
	static_assert(sizeof(PaddedConstantBuffer) == 2 * D3D12_CONSTANT_BUFFER_DATA_PLACEMENT_ALIGNMENT, "PaddedConstantBuffer is not aligned properly");

    void Update(DX::StepTimer const& timer);
    void Render();

    void Clear();

    void CreateDeviceDependentResources();
    void CreateWindowSizeDependentResources();

    // Device resources.
    std::unique_ptr<DX::DeviceResources>        m_deviceResources;

    // Rendering loop timer.
    uint64_t                                    m_frame;
    DX::StepTimer                               m_timer;

    // Input devices.
    std::unique_ptr<DirectX::GamePad>           m_gamePad;

    DirectX::GamePad::ButtonStateTracker        m_gamePadButtons;
        
    // DirectXTK objects.						 
	Microsoft::WRL::ComPtr<ID3D12RootSignature>  m_rootSignature;
	Microsoft::WRL::ComPtr<ID3D12PipelineState>  m_lambertPipelineState;
	Microsoft::WRL::ComPtr<ID3D12PipelineState>  m_solidColorPipelineState;
	Microsoft::WRL::ComPtr<ID3D12Resource>       m_vertexBuffer;
	Microsoft::WRL::ComPtr<ID3D12Resource>       m_indexBuffer;
	Microsoft::WRL::ComPtr<ID3D12Resource>       m_perFrameConstants;
	PaddedConstantBuffer*                        m_mappedConstantData;
    D3D12_GPU_VIRTUAL_ADDRESS                    m_constantDataGpuAddr;
	D3D12_VERTEX_BUFFER_VIEW                     m_vertexBufferView;
	D3D12_INDEX_BUFFER_VIEW                      m_indexBufferView;
	
	// In this simple sample, we know that there are three draw calls
	// and we will update the scene constants for each draw call.
	static const unsigned int                    c_numDrawCalls = 3;

	// A synchronization fence and an event. These members will be used
	// to synchronize the CPU with the GPU so that there will be no
	// contention for the constant buffers. 
	Microsoft::WRL::ComPtr<ID3D12Fence>          m_fence;
	Microsoft::WRL::Wrappers::Event              m_fenceEvent;

	// Index in the root parameter table
	static const UINT                            c_rootParameterCB = 0;

	// Scene constants, updated per-frame
	float                                        m_curRotationAngleRad;

	// These computed values will be loaded into a ConstantBuffer
	// during Render
	DirectX::XMFLOAT4X4                          m_worldMatrix;
	DirectX::XMFLOAT4X4                          m_viewMatrix;
	DirectX::XMFLOAT4X4                          m_projectionMatrix;
	DirectX::XMFLOAT4                            m_lightDirs[2];
	DirectX::XMFLOAT4                            m_lightColors[2];
	DirectX::XMFLOAT4                            m_outputColor;
};