CodeGo.net>如何创建一个端点为鼠标位置,但仅面向一个方向的线渲染器

我有两个对象,它们之间有一条线,就像这样：

我想用对象的一个​​起点和鼠标位置作为终点来创建另一条线,但是仍要面对第二个对象,这看起来像第一行填充了鼠标所在的位置,如下所示：

(据我所知)无法在Unity中设置线条渲染器的方向,那么如何实现呢？

连接形状的代码：

 public void AddShape(GameObject shape) {
    selectedShape = shape;
    selectedShapeComp = shape.GetComponent<Shape>();

    if (!selectedShapes.Contains(selectedShape) && (selectedShapes.Count == 0 || selectedShape.CompareTag(selectedShapes[0].tag))) {
        currentAdjacentShapes = selectedShapeComp.GetAdjacentShapes();

        if (selectedShapes.Count == 0 && !selectedShapeComp.key) return; //If it's first and not a key, don't add it
        if (selectedShapes.Count == 0 && selectedShapeComp.key) activeKeys++; //If it's first and is a key, continue

        FindCurrentlyAdjacentShapes();

        if (currentAdjacentShapes != null && !currentAdjacentShapes.Contains(selectedShape)) return; //If it's not adjacent to prevIoUs shape, don't add it

        selectedShapes.Add(selectedShape);
        MarkShape();

        if (selectedShapes.Count > 1 && selectedShapeComp.key) MarkLeftOutShapes();

        SelectionLinespawner.instance.SpawnLine();
    }

    ClearShapesAhead();
    CalculateSelectedShapesAmount();
}

private void RemoveShape(int index) {
    UnmarkShape(selectedShapes[index]);
    selectedShapes.RemoveAt(index);
}

private void ClearShapesAhead() {
    for (int i = selectedShapes.Count; i > selectedShapeComp.selectedPos; i--) {
        RemoveShape(i - 1);
    }
}

private void FindCurrentlyAdjacentShapes() {
    if (selectedShapes.Count > 1) {
        currentAdjacentShapes = selectedShapes[selectedShapes.Count - 1].GetComponent<Shape>().GetAdjacentShapes();
    }
}

private void MarkLeftOutShapes() {
    var shapes = new List<GameObject>();

    switch (selectedShape.tag) {
        case "Diamond":
            shapes = LevelLoader.instance.currentLevel.GetAllDiamonds();
            break;
        case "Triangle":
            shapes = LevelLoader.instance.currentLevel.GetAllTriangles();
            break;
    }

    foreach (var shape in shapes) {
        if (!selectedShapes.Contains(shape)) {
            Debug.Log("Not selected: " + shape.name);
        }
    }
}

private void MarkShape() {
    selectedShape.gameObject.GetComponent<SpriteRenderer>().color = Color.black;
    selectedShape.gameObject.GetComponent<Animator>().SetTrigger("select");
    selectedShapeComp.selected = true;
    selectedShapeComp.selectedPos = selectedShapes.Count;
}

private void UnmarkShape(GameObject shape) {
    var shapeComp = shape.GetComponent<Shape>();
    shapeComp.selected = true;
    shapeComp.selectedPos = 0;
    shape.gameObject.GetComponent<SpriteRenderer>().color = Color.white;
}

private void CalculateSelectedShapesAmount() {
    switch (selectedShape.tag) {
        case "Diamond":
            LevelLoader.instance.currentLevel.selectedDiamonds = selectedShapes.Count;
            break;
        case "Triangle":
            LevelLoader.instance.currentLevel.selectedTriangles = selectedShapes.Count;
            break;
    }
}

private void DrawLines() {
    foreach (var shape in LevelLoader.instance.currentLevel.GetAllShapes()) {
        var adjacentShapes = shape.GetComponent<Shape>().GetAdjacentShapes();

        foreach (var adjacentShape in adjacentShapes) {
            var lineClone = Instantiate(line);
            lineClone.transform.parent = shape.transform;
            var lineComp = lineClone.GetComponent<Line>();

            foreach (Transform child in adjacentShape.transform) {
                if (child.CompareTag("Line"))
                    if (child.GetComponent<Line>().origin != adjacentShape)
                        lineComp.DrawLine(shape, adjacentShape);
            }

            if (!lineComp.IsDrawn())
                Destroy(lineClone);
        }
    }
}

解决方法:

以下是实现所需内容的步骤：

>在两个对象和相机定义的平面上找到鼠标的世界位置,
>查找从该位置到两个对象之间的直线的最近点,
>从起始对象到最接近的点画一条线

这是可以指导您的代码：

using UnityEngine;
public class Question : MonoBehavIoUr {
    public Vector3 startPosition = Vector3.left * 5;
    public Vector3 endPosition = Vector3.right * 5;

    void OnDrawGizmos() {
        Gizmos.color = Color.blue;
        Gizmos.DrawCube(startPosition, Vector3.one);
        Gizmos.DrawSphere(endPosition, 1);

        Gizmos.color = Color.yellow;
        Gizmos.DrawLine(startPosition, endPosition);

        var mouseRay = Camera.main.ScreenPointToRay(Input.mousePosition);
        var mousePos = mouseRay.GetPoint(Mathf.Abs(Camera.main.transform.position.z));
        var pointOnLine = ClosestPointOnLine(startPosition, endPosition, mousePos, true);

        Gizmos.color = Color.black;
        Gizmos.DrawLine(startPosition, pointOnLine);
    }

    /// <summary> Returns the point nearest point to the [point] on the line given by start and end points, [linestart] and [lineEnd]</summary>
    /// <param name="clampLine"> If true, the returned point will be on the line segment, rather than the line. </param>
    public static Vector3 ClosestPointOnLine(Vector3 linestart, Vector3 lineEnd, Vector3 point, bool clampLine = false) {
        var dif = lineEnd - linestart;
        var direction = Vector3.normalize(dif);
        float closestPoint = Vector3.Dot((point - linestart), direction) / dif.magnitude;
        if (clampLine)
            closestPoint = Mathf.Clamp(closestPoint, 0, 1);
        return linestart + (closestPoint * dif);
    }
}

要测试此代码,只需将其粘贴到文件中,在场景中创建一个游戏对象,然后将此组件添加到其中.这仅适用于正交摄影机.

ClosestPointOnLine方法可以在许多情况下为您提供帮助,因此我将其记录在案.