如何在 Canvas rect 中检查 UI rect答案

【问题标题】：how to check UI rect inside Canvas rect如何在 Canvas rect 中检查 UI rect
【发布时间】：2020-07-10 15:21:06
【问题描述】：

如何在 Canvas rect 中检查 UI rect？

rect.contains(Vector2) 是 Vector2...

rect.overlaps(Rect) 不会为假，除非完全在外面……

void Update()
{
    Vector2 pos;
    var screenPos = Camera.main.WorldToScreenPoint(targetTransform.position + offset);
    RectTransformUtility.ScreenPointToLocalPointInRectangle(canvasRectTransform, screenPos, uiCamera, out pos);
    if (!CheckInsideRect(myRectTransform.rect,canvasRectTransform.rect))
    {
        myRectTransform.localPosition = pos;
    }
}

我想要得到的结果

【问题讨论】：

标签： c# unity3d

【解决方案1】：

您可以通过使用一些扩展方法来“手动”完成，例如

public static class RectTransformExtensions
{
    ///<summary>
    /// Returns a Rect in WorldSpace dimensions using <see cref="RectTransform.GetWorldCorners"/>
    ///</summary>
    public static Rect GetWorldRect(this RectTransform rectTransform)
    {
        // This returns the world space positions of the corners in the order
        // [0] bottom left,
        // [1] top left
        // [2] top right
        // [3] bottom right
        var corners = new Vector3[4];
        rectTransform.GetWorldCorners(corners);

        Vector2 min = corners[0];
        Vector2 max = corners[2];
        Vector2 size = max - min;
 
        return new Rect(min, size);
    }
 
    ///<summary>
    /// Checks if a <see cref="RectTransform"/> fully encloses another one
    ///</summary>
    public static bool FullyContains (this RectTransform rectTransform, RectTransform other)
    {       
        var rect = rectTransform.GetWorldRect();
        var otherRect = other.GetWorldRect();

        // Now that we have the world space rects simply check
        // if the other rect lies completely between min and max of this rect
        return rect.xMin <= otherRect.xMin 
            && rect.yMin <= otherRect.yMin 
            && rect.xMax >= otherRect.xMax 
            && rect.yMax >= otherRect.yMax;
    }
}

见RectTransform.GetWorldCorners

所以你会像这样使用它

if (!canvasRectTransform.FullyContains(myRectTransform))
{
    ...
}

【讨论】：