c# - 屏幕截图后图像上的 Unity 水印

Question

我想在我的图片上添加水印，这是我用来截图的代码。有人可以教我如何在图像中添加水印吗？我想在图片的右上角有一个小 Logo 。

我正在尝试研究是否可以实现我在 Canvas 中保留的内容，以便在截取屏幕截图时保留(现实生活)。但没有运气。如果有人能在这里帮助我，我将不胜感激!

public string MakePhoto(bool openIt)
{          
    int resWidth = Screen.width;
    int resHeight = Screen.height;

    Texture2D screenShot = new Texture2D(resWidth, resHeight, TextureFormat.RGB24, false); //Create new texture
    RenderTexture rt = new RenderTexture(resWidth, resHeight, 24);        

    // hide the info-text, if any
    if (infoText) 
    {
        infoText.text = string.Empty;
    }
    // render background and foreground cameras
    if (backroundCamera && backroundCamera.enabled) 
    {
        backroundCamera.targetTexture = rt;
        backroundCamera.Render();
        backroundCamera.targetTexture = null;
    }

    if (backroundCamera2 && backroundCamera2.enabled) 
    {
        backroundCamera2.targetTexture = rt;
        backroundCamera2.Render();
        backroundCamera2.targetTexture = null;
    }

    if (foreroundCamera && foreroundCamera.enabled) 
    {
        foreroundCamera.targetTexture = rt;
        foreroundCamera.Render();
        foreroundCamera.targetTexture = null;
    }

    // get the screenshot
    RenderTexture prevActiveTex = RenderTexture.active;
    RenderTexture.active = rt;

    screenShot.ReadPixels(new Rect(0, 0, resWidth, resHeight), 0, 0);

    // clean-up
    RenderTexture.active = prevActiveTex;
    Destroy(rt);

    byte[] btScreenShot = screenShot.EncodeToJPG();
    Destroy(screenShot);

    #if !UNITY_WSA
    // save the screenshot as jpeg file
    string sDirName = Application.persistentDataPath + "/Screenshots";
    if (!Directory.Exists(sDirName))
        Directory.CreateDirectory (sDirName);

    string sFileName = sDirName + "/" + string.Format ("{0:F0}", Time.realtimeSinceStartup * 10f) + ".jpg";
    File.WriteAllBytes(sFileName, btScreenShot);

    Debug.Log("Photo saved to: " + sFileName);
    if (infoText) 
    {
        infoText.text = "Saved to: " + sFileName;
    }

    // open file
    if(openIt)
    {
        System.Diagnostics.Process.Start(sFileName);
    }

    return sFileName;

PS:我发现这个可能有用吗？

public Texture2D AddWatermark(Texture2D background, Texture2D watermark)
{

    int startX = 0;
    int startY = background.height - watermark.height;

    for (int x = startX; x < background.width; x++)
    {

        for (int y = startY; y < background.height; y++)
        {
            Color bgColor = background.GetPixel(x, y);
            Color wmColor = watermark.GetPixel(x - startX, y - startY);

            Color final_color = Color.Lerp(bgColor, wmColor, wmColor.a / 1.0f);

            background.SetPixel(x, y, final_color);
        }
    }

    background.Apply();
    return background;
}

Answer 1

1. 在 ProjectsView 中选择导入的图像，并在检查器中将 TextureType 设置为 Sprite(2D 和 UI)(参见 Sprites Manual ) 并点击应用

2. 为它添加一个 Sprite 字段到您的类中

   public Texture2D watermark;
   

3. 在检查器中引用水印

4. 您可以通过为每个像素添加两个纹理的 Color 值来简单地将水印添加为叠加层(这里假设它们具有相同的大小!)

   如果您只想在纹理的某个矩形中添加水印，则必须相应地缩放它并使用 Texture2D.SetPixels(int x, int y, int blockWidth, int blockHeight, Color[] colors)(这假设水印图像的像素小于屏幕截图!)，例如

   private static void AddWaterMark(Texture2D texture, Texture2D watermarkTexture)
   {
       int watermarkWidth = watermarkTexture.width;
       int watermarkHeight = watermarkTexture.height;
   
       // In Unity differrent to most expectations the pixel corrdinate
       // 0,0 is not the top-left corner but instead the bottom-left
       // so since you want the whatermark in the top-right corner do
       int startx = texture.width - watermarkWidth;  
       // optionally you could also still leave a border of e.g. 10 pixels by using
       // int startx = texture.width - watermarkWidth - 10;
   
       // same for the y axis
       int starty = texture.height - watermarkHeight;
   
       Color[] watermarkPixels = watermarkTexture.GetPixels();
       // get the texture pixels for the given rect
       Color[] originalPixels = texture.GetPixels(startx, starty, watermarkWidth, watermarkHeight);
   
       for(int i = 0; i < watermarkPixels.Length; i++)
       {
           var pixel = watermarkPixels[i];
           // adjust the alpha value of the whatermark
           pixel.a *= 0.5f;
           // add watermark pixel to original pixel
           originalPixels[i] += pixel;
       }
   
       // write back the changed texture data
       texture.SetPixels(startx, starty, watermarkWidth, watermarkHeight, originalPixels);
       texture.Apply();
   }
   

   这样称呼

   screenShot.ReadPixels(new Rect(0, 0, resWidth, resHeight), 0, 0);
   AddWaterMark(screenShot, watermark);