Unity 获取windows原始输入 GetRawInputData

要在Unity中获取Windows的原始输入，可以使用Windows API来实现。下面是一个示例代码，展示了如何使用GetRawInputData函数来获取Windows原始输入数据：

using UnityEngine;
using System;
using System.Runtime.InteropServices;

public class RawInputExample : MonoBehaviour
{
    [StructLayout(LayoutKind.Sequential)]
    struct RAWINPUTDEVICE
    {
        public ushort usUsagePage;
        public ushort usUsage;
        public uint dwFlags;
        public IntPtr hwndTarget;
    }

    [StructLayout(LayoutKind.Sequential)]
    struct RAWINPUTHEADER
    {
        public uint dwType;
        public uint dwSize;
        public IntPtr hDevice;
        public IntPtr wParam;
    }

    [StructLayout(LayoutKind.Sequential)]
    struct RAWMOUSE
    {
        public ushort usFlags;
        public uint ulButtons;
        public uint ulRawButtons;
        public int lLastX;
        public int lLastY;
        public uint ulExtraInformation;
    }

    const int WM_INPUT = 0x00FF;

    [DllImport("user32.dll")]
    static extern uint GetRawInputData(IntPtr hRawInput, uint uiCommand, IntPtr pData, ref uint pcbSize, uint cbSizeHeader);

    [DllImport("user32.dll")]
    static extern bool RegisterRawInputDevices(RAWINPUTDEVICE[] pRawInputDevices, uint uiNumDevices, uint cbSize);

    void Start()
    {
        RAWINPUTDEVICE[] rawInputDevices = new RAWINPUTDEVICE[1];
        rawInputDevices[0].usUsagePage = 0x01; // HID_USAGE_PAGE_GENERIC
        rawInputDevices[0].usUsage = 0x02; // HID_USAGE_GENERIC_MOUSE
        rawInputDevices[0].dwFlags = 0x00000100; // RIDEV_INPUTSINK
        rawInputDevices[0].hwndTarget = IntPtr.Zero;

        if (!RegisterRawInputDevices(rawInputDevices, (uint)rawInputDevices.Length, (uint)Marshal.SizeOf(typeof(RAWINPUTDEVICE))))
        {
            Debug.LogError("Failed to register raw input devices");
        }
    }

    void Update()
    {
        uint dataSize = 0;
        GetRawInputData(IntPtr.Zero, 0x10000003, IntPtr.Zero, ref dataSize, (uint)Marshal.SizeOf(typeof(RAWINPUTHEADER)));

        if (dataSize > 0)
        {
            IntPtr data = Marshal.AllocHGlobal((int)dataSize);
            if (GetRawInputData(IntPtr.Zero, 0x10000003, data, ref dataSize, (uint)Marshal.SizeOf(typeof(RAWINPUTHEADER))) == dataSize)
            {
                RAWINPUTHEADER header = Marshal.PtrToStructure<RAWINPUTHEADER>(data);
                if (header.dwType == 0)
                {
                    RAWMOUSE mouseData = Marshal.PtrToStructure<RAWMOUSE>(header.hDevice);
                    int deltaX = mouseData.lLastX;
                    int deltaY = mouseData.lLastY;

                    Debug.Log("Mouse Delta: " + deltaX + ", " + deltaY);
                }
            }

            Marshal.FreeHGlobal(data);
        }
    }

    protected override void WndProc(ref Message message)
    {
        if (message.Msg == WM_INPUT)
        {
            base.WndProc(ref message);
            return;
        }

        base.WndProc(ref message);
    }
}

上面的示例代码中，首先通过RegisterRawInputDevices函数注册原始输入设备（这里是鼠标），然后在Update函数中使用GetRawInputData函数来获取原始输入数据。在获取到数据后，我们可以解析RAWMOUSE结构体，从中获取鼠标的增量位置（lLastX和lLastY），并进行相应的处理。

请注意，由于涉及到Windows API的调用，需要将上述代码放置在派生自UnityEngine.Windows.WindowsWindow类的自定义窗口脚本中，并确保脚本被正确添加到场景中。此外，还需要在Unity项目的Player Settings中启用"Allow 'unsafe' Code"选项。

此外，需要注意的是，使用Windows API来获取原始输入数据可能会涉及到操作系统的特定性，因此在不同操作系统环境下可能会有所差异。建议在使用前仔细阅读Windows API文档，并根据实际需求进行相应的调整和适配。