岳 程式與鍵盤間的故事

　
using UnityEngine;
using UnityEngine.UI;


/// <summary>
/// 該效果為 UGUI Text 文字顏色漸層效果. 
/// </summary>
[AddComponentMenu( "UI/Effects/Gradient" )]
public class TextGradient : BaseMeshEffect
{
    public Color32 topColor = Color.white;
    public Color32 bottomColor = Color.black;


    public override void ModifyMesh( VertexHelper vh )
    {
        float bottomY = -1;
        float topY = -1;

        for ( int i = 0; i < vh.currentVertCount; i++ )
        {
            UIVertex v = new UIVertex();
            vh.PopulateUIVertex( ref v, i );

            if ( bottomY == -1 ) 
                bottomY = v.position.y;
            if ( topY == -1 ) 
                topY = v.position.y;

            if ( v.position.y > topY ) 
                topY = v.position.y;
            else if ( v.position.y < bottomY ) 
                bottomY = v.position.y;
        }


        float uiElementHeight = topY - bottomY;

        for ( int i = 0; i < vh.currentVertCount; i++ )
        {
            UIVertex v = new UIVertex();
            vh.PopulateUIVertex( ref v, i );

            v.color = Color32.Lerp( bottomColor, topColor, (v.position.y - bottomY) / uiElementHeight );
            vh.SetUIVertex( v, i );
        }
    }

}