Unity3d Automatically fix texture size on import (very useful if you have big textures which has bigger size than default 1024 or 2048 value)

AtlasTexturePreprocessor.cs

// reflexion method posted by numberkruncher
// here http://forum.unity3d.com/threads/getting-original-size-of-texture-asset-in-pixels.165295/

public class AtlasTexturePostprocessor : AssetPostprocessor {
	public const int PixelsPerUnit = 100;

	void OnPreprocessTexture(){
		Texture2D tex = AssetDatabase.LoadAssetAtPath(assetPath, typeof(Texture2D )) as Texture2D;
		TextureImporter importer = assetImporter as TextureImporter;
		int textureHeight;
		FixTextureSize(tex,importer, out textureHeight);
	}

	static int[] textureSizes = new int[] {
		32,
		64,
		128,
		256,
		512,
		1024,
		2048,
		4096
	};

	void FixTextureSize (Texture2D tex, TextureImporter importer, out int textureRealHeigh)
	{
		int width, height, max;
		GetImageSize(tex,out width, out height);
		textureRealHeigh = height;
		max = Mathf.Max(width, height);
		int size = 1024; //Default size
		for (int i = 0; i < textureSizes.Length; i++) {
			if (textureSizes[i] >= max){
				size = textureSizes[i];
				break;				
			}
		}
		importer.maxTextureSize = size;

	}
}