using System.Collections;
using System.Collections.Generic;
using UnityEngine;
using UnityEngine.Assertions;
using UnityEngine.UI;

[RequireComponent (typeof(Renderer))]
public class GetSpriteInfo : MonoBehaviour
{
	[SerializeField] Sprite sprite;

	void Start ()
	{
		// UVが取得できるか確認
		Assert.IsTrue (sprite.packed);
		Assert.IsTrue (sprite.packingRotation == SpritePackingRotation.None);
		Assert.IsTrue (sprite.packingMode == SpritePackingMode.Rectangle);

		// SpriteからTextureを取得してUVを取得する
		var tex = sprite.texture;
		var rect = sprite.textureRect;

		MaterialPropertyBlock block = new MaterialPropertyBlock ();
		block.SetVector ("_MainTex_ST", new Vector4 (
			rect.width / tex.width, rect.height / tex.height,
			rect.xMin / tex.width, rect.yMin / tex.height));
		block.SetTexture ("_MainTex", tex);
		GetComponent<Renderer> ().SetPropertyBlock (block);
	}
}