使用unity项目开发过程中需要用到系统截图功能时，其实主要的做法是将RenderTexture转换为Texture2D，然后再转为byte数组，最后创建图片文件，写入内存。下面是代码演示：

public static bool SaveRenderTextureToPNG(RenderTexture rt, string contents, string pngName)

{

Debug.Log("正在保存PNG图片...." + contents + "....." + pngName);

RenderTexture prev = RenderTexture.active;

RenderTexture.active = rt;

Texture2D png = new Texture2D(rt.width, rt.height, TextureFormat.ARGB32, false);

png.ReadPixels(new Rect(0, 0, rt.width, rt.height), 0, 0);

byte[] bytes = png.EncodeToPNG();

// if (!Directory.Exists(contents))

// Directory.CreateDirectory(contents);

string path = Path.Combine(Application.dataPath, pngName + ".jpeg");

FileStream file = File.Open(path, FileMode.Create);

BinaryWriter writer = new BinaryWriter(file);

writer.Write(bytes);

file.Close();

Texture2D.DestroyImmediate(png);

png = null;

RenderTexture.active = prev;

return true;

}

}