using UnityEngine;

namespace General {
    [ExecuteInEditMode]
    [RequireComponent(typeof(Camera))]
    [AddComponentMenu("Image Effects/2D Sprite/Outline")]
    public class Outline : MonoBehaviour {
        [SerializeField] Color _outlineColor = Color.red;

        public Color outlineColor {
            get { return _outlineColor; }
            set { _outlineColor = value; }
        }

        [SerializeField] float _sampleDistance = 2;

        public float sampleDistance {
            get { return _sampleDistance; }
            set { _sampleDistance = value; }
        }

        [SerializeField] Shader shader;

        Material _material;

        void Setup() {
            if (_material == null) {
                _material = new Material(shader);
                _material.hideFlags = HideFlags.DontSave;
            }
        }

        void OnRenderImage(RenderTexture source, RenderTexture destination) {
            Setup();

            _material.SetFloat("_Distance", _sampleDistance);
            _material.SetColor("_Color", _outlineColor);

            Graphics.Blit(source, destination, _material);
        }
    }
}