//--------------------------------------------------------
//    [Author]:           第二世界
//    [  Date ]:           Wednesday, August 23, 2017
//--------------------------------------------------------
using UnityEngine;
using System.Collections;
using UnityEngine.UI;
using System;
using System.Collections.Generic;


public class OffsetImage:BaseMeshEffect {

    [SerializeField]
    Vector2 m_Offset;
    public Vector2 offset {
        get {
            return m_Offset;
        }
        set {
            m_Offset = value;

        }
    }

    public override void ModifyMesh(VertexHelper vh) {
        List<UIVertex> vertexs = new List<UIVertex>();
        vh.GetUIVertexStream(vertexs);

        if(vertexs == null || vertexs.Count == 0) {
            return;
        }
        vh.Clear();

        var positions = new Vector3[3];
        var uv0s = new Vector2[3];

        var firstQuard = new UIVertex[6] {
            vertexs[0],
            vertexs[1],
            vertexs[2],
            vertexs[3],
            vertexs[4],
            vertexs[5]
        };

        for(var i = 0;i < firstQuard.Length;i++) {
            var vertex = firstQuard[i];
            var position = vertex.position + new Vector3(offset.x,offset.y,0);
            vertex.position = position;
            firstQuard[i] = vertex;

            if((i % 3) == 2) {
                positions[0] = firstQuard[i - 2].position;
                uv0s[0] = firstQuard[i - 2].uv0;
                positions[1] = firstQuard[i - 1].position;
                uv0s[1] = firstQuard[i - 1].uv0;
                positions[2] = firstQuard[i].position;
                uv0s[2] = firstQuard[i].uv0;

                UIUtility.AddTriangle(vh,positions,Color.white,uv0s);
            }
        }



        var index = 5 * 6;
        for(int i = 0;i < vertexs.Count;i++) {

            if(i > index) {

            }

            if((i % 3) == 2) {
                positions[0] = vertexs[i - 2].position;
                uv0s[0] = vertexs[i - 2].uv0;
                positions[1] = vertexs[i - 1].position;
                uv0s[1] = vertexs[i - 1].uv0;
                positions[2] = vertexs[i].position;
                uv0s[2] = vertexs[i].uv0;

                UIUtility.AddTriangle(vh,positions,Color.white,uv0s);
            }
        }




    }

}