Unity 之 生成二维码 & 融合图片

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Unity 生成二维码，并将二维码和已有背景图片融合，保存到本地。

1、场景的搭建

2、代码的编写（参考链接）

using System.IO;
using UnityEngine;
using UnityEngine.UI;
using ZXing;
using ZXing.Common;

public class CreateCode_2 : MonoBehaviour
{
    //生成二维码指定RawImage
    public RawImage Raw_QRCode; 
    //要和二维码融合的背景图
    public RawImage Raw_Bg;
    //和融合后的结果图 （保存到本地的图）
    public RawImage Raw_Result;

    void Start()
    {
        //生成二维码
        Raw_QRCode.texture = GenerateQRImageConstantSize("https://blog.csdn.net/czhenya", 256, 256);
   
        //融合
        Raw_Result.texture = MixImagAndQRCode(TextureToTexture2D(Raw_Bg.texture), GenerateQRImageConstantSize("http://www.baidu.com", 256, 256));

        //保存知道本地 ... 在本地的路径 C:\Users\Administrator\AppData\LocalLow\DefaultCompany\DefaultCompany  
        //Application.persistentDataPath + "/ShotShare.png" 直接设置此路径为分享图片路径
        Debug.Log(saveMainTextureToPng((Application.persistentDataPath + "/ShotShare.png"), Raw_Result.texture));
    }


    /// <summary>
    /// 生成固定大小的二维码(256,256)...
    /// </summary>
    /// <param name="content">要显示的内容</param>
    /// <param name="width">宽</param>
    /// <param name="height">高</param>
    /// <returns></returns>
    public static Texture2D GenerateQRImageConstantSize(string content, int width, int height)
    {
        // 编码成color32
        EncodingOptions options = null;
        BarcodeWriter writer = new BarcodeWriter();
        options = new EncodingOptions
        {
            Width = width,
            Height = height,
            Margin = 1,
        };
        options.Hints.Add(EncodeHintType.CHARACTER_SET, "UTF-8");
        writer.Format = BarcodeFormat.QR_CODE;
        writer.Options = options;
        Color32[] colors = writer.Write(content);
        // 转成texture2d
        Texture2D texture = new Texture2D(width, height);
        texture.SetPixels32(colors);
        texture.Apply();
        return texture;
    }


    /// <summary>
    /// 融合图片和二维码,得到新Texture2D ...
    /// 根据背景图的大小比例
    /// </summary>
    /// <param name="tex_base">底图</param>
    /// <param name="tex_code">二维码</param>
    public static Texture2D MixImagAndQRCode(Texture2D tex_base, Texture2D tex_code)
    {
        Texture2D newTexture = Instantiate(tex_base) as Texture2D; ;
        Vector2 uv = new Vector2((tex_base.width - tex_code.width) / tex_base.width, (tex_base.height - tex_code.height) / tex_base.height);
        for (int i = 0; i < tex_code.width; i++)
        {
            for (int j = 0; j < tex_code.height; j++)
            {
                float w = uv.x * tex_base.width - tex_code.width + i;
                float h = uv.y * tex_base.height - tex_code.height + j;
                //从底图图片中获取到（w，h）位置的像素
                Color baseColor = newTexture.GetPixel((int)w, (int)h);
                //从二维码图片中获取到（i，j）位置的像素
                Color codeColor = tex_code.GetPixel(i, j);
                //融合
                newTexture.SetPixel((int)w, (int)h, codeColor);
            }
        }
        newTexture.Apply();
        return newTexture;
    }
     
    /// <summary>
    /// Texture转换成Texture2D...
    /// </summary>
    /// <param name="texture"></param>
    /// <returns></returns>
    Texture2D TextureToTexture2D(Texture texture)
    {
        Texture2D texture2D = new Texture2D(texture.width, texture.height, TextureFormat.RGBA32, false);

        RenderTexture currentRT = RenderTexture.active;

        RenderTexture renderTexture = RenderTexture.GetTemporary(texture.width, texture.height, 32);
        Graphics.Blit(texture, renderTexture);

        RenderTexture.active = renderTexture;
        texture2D.ReadPixels(new Rect(0, 0, renderTexture.width, renderTexture.height), 0, 0);
        texture2D.Apply();

        RenderTexture.active = currentRT;
        RenderTexture.ReleaseTemporary(renderTexture);

        return texture2D;
    }

    /// <summary>
    /// 将Texture转为本地PNG ...
    /// </summary>
    /// <param name="filePath">保存路径，（分享时直接使用）</param>
    /// <param name="teture">要保存的Texture</param>
    /// <returns></returns>
    public static bool saveMainTextureToPng(string filePath, Texture teture)
    {
        if (teture.GetType() != typeof(Texture2D))
        {
            return false;
        }
        Texture2D savedTexture = (Texture2D)teture;
        try
        {
            Texture2D newTexture = new Texture2D(savedTexture.width, savedTexture.height, TextureFormat.RGBA32, false);
            newTexture.SetPixels(0, 0, savedTexture.width, savedTexture.height, savedTexture.GetPixels());
            newTexture.Apply();
            byte[] bytes = newTexture.EncodeToPNG();
            if (bytes != null && bytes.Length > 0)
            {
                if (File.Exists(filePath))
                {
                    File.Delete(filePath);
                }
                System.IO.File.WriteAllBytes(filePath, bytes);
            }
        }
        catch (IOException ex)
        {
            return false;
        }
        return true;
    }
}