由于距离而改变游戏对象颜色答案

【问题标题】：Change GameObject color due to distance由于距离而改变游戏对象颜色
【发布时间】：2018-06-11 12:39:30
【问题描述】：

我正在尝试使用此代码将对象的红色值更改为它与相机之间的距离：

using UnityEngine;
using UnityEngine.UI;     

public class DistanceToCheckpoint : MonoBehaviour {

    // Reference to checkpoint position
    [SerializeField]
    private Transform checkpoint;

    // Reference to UI text that shows the distance value
    [SerializeField]
    private Text distanceText;

    // Calculated distance value
    private float distance;

    // Update is called once per frame
    private void Update()
    {
        // Calculate distance value between character and checkpoint
        distance = (checkpoint.transform.position - transform.position).magnitude;

        // Display distance value via UI text
        // distance.ToString("F1") shows value with 1 digit after period
        // so 12.234 will be shown as 12.2 for example
        // distance.ToString("F2") will show 12.23 in this case
        distanceText.text = "Distance: " + distance.ToString("F1") + " meters";
    }

}

然后我把它放在 Update() 中：

checkpoint.GetComponent<Renderer>().material.color = new Color(1, (255 - distance.ToString("F1")), 0, 0);

【问题讨论】：

代码现在做了什么？你想让它做什么呢？
255 - distance.ToString("F1") 编译吗？
控制台显示Assets/Scripts/DistanceToCheckpoint.cs(29,76): error CS0019: Operator '-' cannot be applied to operands of type 'int' and 'string'
我只是删除了.ToString("F1")，检查点在 0 到 255 距离之间是黄色的，在它变成红色之后
我希望红色检查点靠近它时变成黑色

标签： c# unity3d gameobject

【解决方案1】：

您需要确定物体完全变红的距离。然后您可以根据该距离的因素修改该值。

例如，如果您希望它在 50 及以上距离处变为红色，您可以这样做...

checkpoint.GetComponent<Renderer>().material.color = new Color(distance/50f, 0, 0);

【讨论】：

为什么没有评论就被否决了？这是测试问题的快速解决方案！
@dome12b 正好相反。当你接近它时，它会变得更红，而不是变黑。值也可能变为负数，不知道这是否有问题。
@SebastianKilb 你是怎么阻止的？如果距离非常近 - 比如 1. 你会得到 49/50 = .98。颜色将是 (.98, 0, 0)，非常红色。如果它很远 - 比如 50，你会得到 0/50 给你一个颜色 (0,0,0) - 黑色。
@ryeMoss Florian 对此发表了评论。 “我希望红色检查站靠近它时变成黑色”
颜色不会随着checkpoint.GetComponent<Renderer>().material.color = new Color(distance/50f, 0, 0); 而改变，我不希望它在我接近时发生残酷但温和的变化

【解决方案2】：

Color的第四个参数是Alpha值（透明度）

0 表示不可见
1 完全可见

并且您输入的值必须是范围从 0 到 1 的浮点值。

float startDistance = 100f;
float blackAtDistance = 5f;

distance -= blackAtDistance;
percentage = distance / maxDistance;
percentage = Mathf.Clamp(percentage, 0, 1);
checkpoint.GetComponent<Renderer>().material.color = new Color(percentage, 0, 0, 1);

我没有测试它，但它应该可以工作。

【讨论】：

【解决方案3】：

我没有包括你所做的一切，只包括与答案有关的部分。我已经评论了它，希望让你遵循推理。

public class DistanceToCheckpoint : MonoBehaviour
{
    // Reference to UI text that shows the distance value
    [SerializeField]
    private Text distanceText;

    // Reference to checkpoint position
    [SerializeField]
    private Transform checkpoint;
    private Material checkpointMaterial;

    [Tooltip ( "This is the color your object starts with." )]
    public Color StartColor;
    [Tooltip ( "This is the distance your object is the Start Color." )]
    public float ColorDistanceFar;
    [Tooltip ( "This is the distance your object becomes full black." )]
    public float ColorDistanceNear;
    private float colourDistanceRange;

    // Calculated distance value
    private float distance;

    private void Start ( )
    {
        colourDistanceRange = ColorDistanceFar - ColorDistanceNear;
        checkpointMaterial = checkpoint.GetComponent<Renderer> ( ).material;
    }

    private void Update ( )
    {
        // Calculate distance value between character and checkpoint
        distance = ( checkpoint.transform.position - transform.position ).magnitude;
        distanceText.text = $"Distance: {distance.ToString ( "F1" )} meters";

        // Start with full color amount.
        float colourAmount = 1;
        // Check to see if the distance is closer than the ColorDistanceNear distance. In which case the colour should be black.
        if ( distance <= ColorDistanceNear ) colourAmount = 0;
        // Else, check to see if the distance is closer than the ColorDistanceFar distance. We need to "normalize" this value.
        else if ( distance < ColorDistanceFar ) colourAmount = ( distance - ColorDistanceNear ) / colourDistanceRange;

        // Now we "multiply" the colour with the colourAmount to get something between the full colour and black.
        checkpointMaterial.color = StartColor * colourAmount;
    }
}

【讨论】：

【解决方案4】：

我只是成功了：

using UnityEngine;
using UnityEngine.UI;     

public class DistanceToCheckpoint : MonoBehaviour {

    // Reference to checkpoint position
    [SerializeField]
    private Transform checkpoint;

    // Calculated distance value
    private float distance;

    // Update is called once per frame
    private void Update()
    {
        // Calculate distance value between character and checkpoint
        distance = (checkpoint.transform.position - transform.position).magnitude;

        checkpoint.GetComponent<Renderer>().material.color = new Color(-(100 - distance), 0, 0);
    }

}

现在我想把它应用到不同的元素上，你认为有办法做一个 foreach 吗？

【讨论】：