【参考情報】 Reading pixel data from material.mainTexture returns grey color - Unity Answers http://answers.unity3d.com/questions/1271693/reading-pixel-data-from-materialmaintexture-return.html Texture を RenderTexture を経由して、 Texture2D に変換。 Texture mainTexture = mat.GetTexture("_MainTex"); // Material のメインテクスチャを取得 Texture2D texture2D = new Texture2D(mainTexture.width, mainTexture.height, TextureFormat.RG