我收到 UnityException 纹理不可读。何，我应该处理它吗？

Question

我不明白这个异常以及如何修复它。

例外情况在第 38 行：

pixels = origTex.GetPixels();

完整的异常消息：

UnityException：纹理“screen_1920x1080_2021-07-09_14-08-00”不可读，无法从脚本访问纹理内存。您可以在纹理导入设置中使纹理可读。

我不知道如何处理。在此之前，这是我第一次遇到此异常。

using System.Collections;
using System.Collections.Generic;
using UnityEngine;
using UnityEngine.UI;

public class RawImagePixelsChange : MonoBehaviour
{
    // Create a blank RawImage and drag this script onto it

    // NOTE: Unless you create a new texture from the image (instead of using it directly),
    // changes will alter the asset itself!
    // Textures must be type 2D/UI and have Read/Write enabled

    // Unity docs say GetPixels32 etc. is faster, but I wasn't able to get the modifyPixels() to work...
    // colors kept wrapping around 255, even with clamps (?)

    RawImage myImage; // texture will be assigned in code, but can assign in Inspector to see in Editor

    public Texture2D origTex; // drag texture to slot in Inspector
    public Texture2D newTex; // leave blank, will be created in code

    public float lightenAmount = 0.1f;

    Color[] pixels;

    void Start()
    {
        var texture = GetComponent<RawImage>().texture;
        origTex = texture as Texture2D;

        myImage = GetComponent<RawImage>();

        // Prints the float equivalent color at pixel (50,50). Note the texture origin is lower left!
        //print("pixel 50, 50 = " + origTex.GetPixel(50, 50));

        if (texture != null && origTex != null)
        {
            pixels = origTex.GetPixels();

            newTex = new Texture2D(origTex.width, origTex.height);

            newTex.SetPixels(pixels);
            newTex.Apply();
            myImage.texture = newTex;
        }
    }

    public void modifyPixels(float lightenAmount) // Press "P" to change pixel colors by lightenAmount
    {
        for (int i = 0; i < pixels.Length; i++)
        {
            pixels[i].r += lightenAmount;
            if (pixels[i].r > 1) pixels[i].r = 1;
            if (pixels[i].r < 0) pixels[i].r = 0;
            pixels[i].g += lightenAmount;
            if (pixels[i].g > 1) pixels[i].g = 1;
            if (pixels[i].g < 0) pixels[i].g = 0;
            pixels[i].b += lightenAmount;
            if (pixels[i].b > 1) pixels[i].b = 1;
            if (pixels[i].b < 0) pixels[i].b = 0;
        }
        newTex.SetPixels(pixels);
        newTex.Apply();
    }
    public void restorePixels() // Press "O" (letter O) to restore original texture/image
    {
        pixels = origTex.GetPixels();
        newTex.SetPixels(pixels);
        newTex.Apply();
    }

    void Update()
    {
        if (Input.GetKeyDown(KeyCode.P))
        {
            modifyPixels(lightenAmount);
        }
        if (Input.GetKeyDown(KeyCode.O))
        {
            restorePixels();
        }
    }

    public float Amount()
    {
        return lightenAmount;
    }
}

Answer 1

单击您的图像，然后在该图像的检查器中选中“高级”上的“读/写启用”框，然后单击“应用”。

Answer 2

通过检查器中的导入设置使其启用读/写。

读/写启用
启用此属性可使用Texture2D.SetPixels、Texture2D.GetPixels 和其他Texture2D 方法从脚本访问纹理数据。在内部，Unity 使用纹理数据的副本进行脚本访问，这使得纹理所需的内存量增加了一倍。因此，默认情况下此属性处于禁用状态，并且仅当您需要脚本访问时才应启用它。有关详细信息，请参阅纹理 2D。