ATLAS是一種將多個PNG文件合并到一個大紋理集中的技術。JSON文件用于描述紋理集中每個圖片在哪里、大小、位置和旋轉因素等等。PNG文件則是紋理集的實際圖像。這種技術常用于游戲開發中，可以減少內存占用，提高游戲的啟動速度。

{
"frames": {
"image0.png":
{
"frame": {"x":0, "y":0, "w":139, "h":135},
"rotated": false,
"trimmed": false,
"spriteSourceSize": {"x":0,"y":0,"w":139,"h":135},
"sourceSize": {"w":139,"h":135}
},
"image1.png":
{
"frame": {"x":0, "y":135, "w":40, "h":38},
"rotated": false,
"trimmed": true,
"spriteSourceSize": {"x":0,"y":0,"w":40,"h":38},
"sourceSize": {"w":40,"h":38}
},
"image2.png":
{
"frame": {"x":139, "y":0, "w":114, "h":142},
"rotated": false,
"trimmed": false,
"spriteSourceSize": {"x":0,"y":0,"w":114,"h":142},
"sourceSize": {"w":114,"h":142}
},
},
"meta": {
"app": "myAppName",
"version": "1.0",
"image": "myAtlas.png",
"format": "RGBA8888",
"size": {"w":253,"h":177},
"scale": "1",
"smartupdate": "$TexturePacker:SmartUpdate:36d3d2e2c3aeeabf3806ab8782ee91d3:fdfa04c4bc3c21cfb727d9a7af3ce097:5f61a401e28aa61654b5a82b82a1cf81$"
}
}

上面的JSON文件是一個ATLAS格式的描述文件。里面包含了幾個圖片的描述信息，包括位置、大小、旋轉等。如果要使用這個ATLAS，我們需要使用ATLAS的解析庫，將指定的JSON文件和PNG文件一起加載，解析成一個個獨立的Sprite對象。這個過程通常由游戲引擎的資源管理器完成。