unity合并贴图,并读取合并贴图中任意位置贴图_unity 合并贴图

1.合并图片

using System;
using System.IO;
using UnityEditor;
using UnityEngine;
 
public class TextureCombine
{
    [MenuItem("Tools/TextureCombine")]
    static void Combine()
    {
        Texture2D pic1 = AssetDatabase.LoadAssetAtPath<Texture2D>("Assets/Images/pic1.jpg");
        Texture2D pic2 = AssetDatabase.LoadAssetAtPath<Texture2D>("Assets/Images/pic2.jpg");
        Texture2D pic3 = AssetDatabase.LoadAssetAtPath<Texture2D>("Assets/Images/pic3.jpg");
        Texture2D pic4 = AssetDatabase.LoadAssetAtPath<Texture2D>("Assets/Images/pic4.jpg");
        Texture2D exportImg = Combine(new[] { pic1, pic2,pic3,pic4 }, new[] { (0, 0), (0, 484),(512,0),(512,512) } , 1024);
        File.WriteAllBytes("Assets/CombineImages/out.jpg", exportImg.EncodeToJPG());
        AssetDatabase.Refresh();
    }
 
    /// <summary>
    /// 合并贴图
    /// </summary>
    /// <param name="texs">贴图</param>
    /// <param name="offsets">贴图位置,左下角(0,0)</param>
    /// <param name="size">自己贴图的大小</param>
    /// <returns></returns>
    static Texture2D Combine(Texture2D[] texs, ValueTuple<int, int>[] offsets, int size)
    {
        Texture2D @out = new Texture2D(size, size, TextureFormat.RGBA32, true);
        for (int i = 0; i < texs.Length; i++)
        {
            var tex = texs[i];
            var offest = offsets[i];
            var width = tex.width;
            var height = tex.height;
            RenderTexture tmp = RenderTexture.GetTemporary(width, height, 0, RenderTextureFormat.Default, RenderTextureReadWrite.Linear);
            Graphics.Blit(tex, tmp);
            RenderTexture previous = RenderTexture.active;
            RenderTexture.active = tmp;
            Texture2D @new = new Texture2D(width, height);
            @new.ReadPixels(new Rect(0, 0, width, height), 0, 0);
            @new.Apply();
            @out.SetPixels(offest.Item1, offest.Item2, width, height, @new.GetPixels());
            RenderTexture.active = previous;
            RenderTexture.ReleaseTemporary(tmp);
        }
        return @out;
    }
}

我自己4个贴图合成的一个贴图

2.读取合并图片中任意位置的图片(示例读取右上角)

using UnityEngine;
using UnityEngine.UI;
using System.IO;
 
public class Test1 : MonoBehaviour
{
    private string path;
    private Texture2D combineTex;
    public RawImage completImg;
    public Image singleImg;
  
    // Start is called before the first frame update
    void Start()
    {
        path = Application.dataPath + "/CombineImages/out.jpg";      
        if (!File.Exists(path))
        {
            print("路径不存在");
            return;
        }
        byte[] combineImgData=  File.ReadAllBytes(path);
        combineTex= ByteToTex2d(combineImgData, 1024, 1024); 
        CombineImg();
        SingleImg();
    }
 
    //合并之后的贴图
    private void CombineImg()
    {
        if(combineTex!=null)
        {
            completImg.texture = combineTex;
        }
        else
        {
            print("combineTex=null");
        }    
    }
    //合并之后贴图中的单个贴图
    private void SingleImg()
    {
        //读取右上角的位置
        Sprite sp = Sprite.Create(combineTex, new Rect(512, 512, 512, 512), new Vector2(0.5f, 0.5f));
        singleImg.sprite = sp;
        //设置图片宽、高
        //singleImg.transform.GetComponent<RectTransform>().sizeDelta = new Vector2(256, 256);       
    }
    public static Texture2D ByteToTex2d(byte[] bytes, int w , int h )
    {
        Texture2D tex = new Texture2D(w, h);
        tex.LoadImage(bytes);
        return tex;
    }
}