Hololens入门之拍照编辑

Hololens入门之拍照编辑

在Hololens的使用过程中，可能会遇到以下场景，使用Hololens进行拍摄照片，然后对照片进行图像识别，但是由于初始拍摄的照片中干扰项太多，影响识别效果，这时就需要截取图片中的有效部分来对图片进行识别。

本项目使用Hololens进行拍照，然后对照片进行裁剪编辑，获取图片的有效区域。

完整代码可在GitHub上进行下载（https://github.com/adjacentech/HoloPhotoEditor）

裁剪过程中通过移动裁剪框的位置，以及改变裁剪框的大小来确定有效裁剪区域（关键代码如下）

using HoloToolkit.Unity.InputModule;using System.Collections;using System.Collections.Generic;using UnityEngine;using System;public class CropBoxManager : MonoBehaviour, INavigationHandler{    private Vector3 manipulationPreviousPosition;    public GameObject imageObject = null;    private float parentWidth = 0;    private float parentHeight = 0;    private Vector3 originalLocalPosition;    private Vector2 originalSizeDelta;    public float minWidth = 100;    public float minHeight = 100;    void Awake()    {        parentWidth = imageObject.GetComponent<RectTransform>().rect.width;        parentHeight = imageObject.GetComponent<RectTransform>().rect.height;        originalLocalPosition = gameObject.GetComponent<RectTransform>().localPosition;        originalSizeDelta = gameObject.GetComponent<RectTransform>().sizeDelta;    }    private void Start()    {    }    // Update is called once per frame    void Update()    {    }    /// <summary>    /// 获取裁剪框的矩形区域    /// </summary>    /// <returns></returns>    public RectTransform GetCropBoxRectTransform()    {        return gameObject.GetComponent<RectTransform>();    }    /// <summary>    /// 获取父对象的大小    /// </summary>    /// <returns></returns>    public Vector2 GetParentSize()    {        return new Vector2(parentWidth, parentHeight);    }    /// <summary>    /// 重置裁剪框的大小和位置    /// </summary>    public void ResetCropBoxTransform()    {        gameObject.GetComponent<RectTransform>().localPosition = new Vector3(originalLocalPosition.x, originalLocalPosition.y, originalLocalPosition.z) ;        gameObject.GetComponent<RectTransform>().sizeDelta = new Vector2(originalSizeDelta.x, originalSizeDelta.y);    }    /// <summary>    /// Navigation手势取消事件    /// </summary>    /// <param name="eventData"></param>    public void OnNavigationCanceled(NavigationEventData eventData)    {        InputManager.Instance.ClearModalInputStack();    }    /// <summary>    /// Navigation手势完成事件    /// </summary>    /// <param name="eventData"></param>    public void OnNavigationCompleted(NavigationEventData eventData)    {        InputManager.Instance.ClearModalInputStack();    }    /// <summary>    /// Navigation手势开始事件    /// </summary>    /// <param name="eventData"></param>    public void OnNavigationStarted(NavigationEventData eventData)    {        if (ToolManager.Instance.selectedTool == null            || ((ToolManager.Instance.selectedTool.type != ToolType.Resize)            && (ToolManager.Instance.selectedTool.type != ToolType.Move))            /*|| (CapturePhotoManager.Instance.GetCurrentStatus() != CurrentStatus.EdittingPhoto)*/)        {            return;        }        InputManager.Instance.PushModalInputHandler(gameObject);    }    /// <summary>    /// Navigation手势更新事件    /// </summary>    /// <param name="eventData"></param>    public void OnNavigationUpdated(NavigationEventData eventData)    {        if (ToolManager.Instance.selectedTool == null            || ((ToolManager.Instance.selectedTool.type != ToolType.Resize)            && (ToolManager.Instance.selectedTool.type != ToolType.Move))            /*|| (CapturePhotoManager.Instance.GetCurrentStatus() != CurrentStatus.EdittingPhoto)*/)        {            return;        }        switch (ToolManager.Instance.selectedTool.type)        {            case ToolType.Move:                Move(eventData);                break;            case ToolType.Resize:                Resize(eventData);                break;            default:                break;        }    }    /// <summary>    /// 平移裁剪框    /// </summary>    /// <param name="eventData"></param>    private void Move(NavigationEventData eventData)    {        Vector3 moveVector = Vector3.one;        float deltaX = 8 * eventData.CumulativeDelta.x;        float deltaY = 8 * eventData.CumulativeDelta.y;        if (Math.Abs(eventData.CumulativeDelta.x) >= Math.Abs(eventData.CumulativeDelta.y))        {            //当水平移动分量大于垂直分量时，水平平移            moveVector = new Vector3(deltaX, 0, 0);        }        else        {            //当垂直移动分量大于水平分量时，垂直平移            moveVector = new Vector3(0, deltaY, 0);        }        //计算边界，重新调整位移        moveVector = RecalculateMoveVector(moveVector);        RectTransform rectTransform = gameObject.GetComponent<RectTransform>();        gameObject.GetComponent<RectTransform>().localPosition = new Vector3(            rectTransform.localPosition.x + moveVector.x,            rectTransform.localPosition.y + moveVector.y,            rectTransform.localPosition.z + moveVector.z);    }    /// <summary>    /// 调整裁剪框的大小    /// </summary>    /// <param name="eventData"></param>    private void Resize(NavigationEventData eventData)    {        if (Math.Abs(eventData.CumulativeDelta.x) >= Math.Abs(eventData.CumulativeDelta.y))        {            //当水平移动分量大于垂直分量时，修改宽度            float deltaX = 10 * eventData.CumulativeDelta.x;            Rect rect = gameObject.GetComponent<RectTransform>().rect;            Rect newRect = new Rect((rect.width + deltaX) / 2, rect.height / 2, rect.width + deltaX, rect.height);            newRect = RecalculateRectWidth(newRect);            gameObject.GetComponent<RectTransform>().sizeDelta = new Vector2(newRect.width, newRect.height);        }        else        {            //当垂直移动分量大于水平分量时，修改高度            float deltaY = 10 * eventData.CumulativeDelta.y;            Rect rect = gameObject.GetComponent<RectTransform>().rect;            Rect newRect = new Rect(rect.width / 2, (rect.height + deltaY) / 2, rect.width, rect.height + deltaY);            newRect = RecalculateRectHeight(newRect);            gameObject.GetComponent<RectTransform>().sizeDelta = new Vector2(newRect.width, newRect.height);        }    }    /// <summary>    /// 重新计算位移    /// </summary>    /// <param name="moveVector"></param>    /// <returns></returns>    private Vector3 RecalculateMoveVector(Vector3 moveVector)    {        RectTransform rectTransform = gameObject.GetComponent<RectTransform>();        Rect rect = rectTransform.rect;        //裁剪框移动不超出大图范围，需要满足以下条件        //-parentWidth / 2 + width / 2 <= x <= parentWidth / 2 - width / 2        //-parentHeight / 2 + height / 2 <= y <= parentHeight / 2 - height / 2        if (((rectTransform.localPosition.x + moveVector.x) >= (-parentWidth / 2 + rect.width / 2))            && ((rectTransform.localPosition.x + moveVector.x) <= (parentWidth / 2 - rect.width / 2))            && ((rectTransform.localPosition.y + moveVector.y) >= (-parentHeight / 2 + rect.height / 2))            && ((rectTransform.localPosition.y + moveVector.y) <= (parentHeight / 2 - rect.height / 2)))        {            return moveVector;        }        float newX = moveVector.x;        float newY = moveVector.y;        //当超出左边框，重新计算水平移动分量        if ((rectTransform.localPosition.x + moveVector.x) < (-parentWidth / 2 + rect.width / 2))        {            newX = -parentWidth / 2 + rect.width / 2 - rectTransform.localPosition.x;        }        //当超出右边框，重新计算水平移动分量        if ((rectTransform.localPosition.x + moveVector.x) > (parentWidth / 2 - rect.width / 2))        {            newX = parentWidth / 2 - rect.width / 2 - rectTransform.localPosition.x;        }        //当超出下边框，重新计算垂直移动分量        if ((rectTransform.localPosition.y + moveVector.y) < (-parentHeight / 2 + rect.height / 2))        {            newY = -parentHeight / 2 + rect.height / 2 - rectTransform.localPosition.y;        }        //当超出上边框，重新计算垂直移动分量        if ((rectTransform.localPosition.y + moveVector.y) > (parentHeight / 2 - rect.height / 2))        {            newY = parentHeight / 2 - rect.height / 2 - rectTransform.localPosition.y;        }        return new Vector3(newX, newY, moveVector.z);    }    /// <summary>    /// 重新计算裁剪框的宽度    /// </summary>    /// <param name="rect">矩形区域</param>    /// <returns>返回矩形区域</returns>    private Rect RecalculateRectWidth(Rect rect)    {        //当裁剪框高度小于最小宽度时，重新调整为最小宽度        if (rect.width < minWidth)        {            return new Rect(minWidth / 2, rect.y, minWidth, rect.height);        }        RectTransform rectTransform = gameObject.GetComponent<RectTransform>();        //在大图范围内进行移动，需满足条件 -parentWidth / 2 + width / 2 <= x <= parentWidth / 2 - width / 2        if ((rectTransform.localPosition.x >= (-parentWidth / 2 + rect.width / 2))            && rectTransform.localPosition.x <= (parentWidth / 2 - rect.width / 2))        {            return rect;        }        //当裁剪框超出左边框时，重新进行调整        if (rectTransform.localPosition.x < (-parentWidth / 2 + rect.width / 2))        {            return new Rect(rectTransform.localPosition.x + parentWidth / 2, rect.y, 2 * rectTransform.localPosition.x + parentWidth, rect.height);        }        //当裁剪框超出右边框时，重新进行调整        if (rectTransform.localPosition.x > (parentWidth / 2 - rect.width / 2))        {            return new Rect(parentWidth/2 - rectTransform.localPosition.x, rect.y, parentWidth- 2 * rectTransform.localPosition.x, rect.height);        }        return rect;    }    /// <summary>    /// 重新计算裁剪框的高度    /// </summary>    /// <param name="rect">矩形区域</param>    /// <returns>返回矩形区域</returns>    private Rect RecalculateRectHeight(Rect rect)    {        //当裁剪框高度小于最小高度时，重新调整为最小高度        if (rect.height < minHeight)        {            return new Rect(rect.x, minHeight / 2, rect.width, minHeight);        }        RectTransform rectTransform = gameObject.GetComponent<RectTransform>();        //在大图范围内进行移动，需满足条件 -parentHeight / 2 + height / 2 <= y <= parentHeight / 2 - height / 2        if ((rectTransform.localPosition.y >= (-parentHeight / 2 + rect.height / 2))            && rectTransform.localPosition.y <= (parentHeight / 2 - rect.height / 2))        {            return rect;        }        //当裁剪框超出下边框时，重新进行调整        if (rectTransform.localPosition.y < (-parentHeight / 2 + rect.height / 2))        {            return new Rect(rect.x, rectTransform.localPosition.y + parentHeight / 2, rect.width, 2 * rectTransform.localPosition.y + parentHeight);        }        //当裁剪框超出上边框时，重新进行调整        if (rectTransform.localPosition.y > (parentHeight / 2 - rect.height / 2))        {            return new Rect(rect.x, parentHeight / 2 - rectTransform.localPosition.y, rect.width, parentHeight - 2 * rectTransform.localPosition.y);        }        return rect;    }}

运行测试

1、点击进行拍照，获取照片

2、选择“移动”选项，上下左右拖拽裁剪框，调整裁剪框的位置

3、选择“调整大小”选项，上下左右拖拽裁剪框，调整裁剪框的大小

4、当调整到合适的位置和大小时，点击确定按钮，最终裁剪出所需要的有效区域