1 files changed, 126 insertions, 0 deletions
diff --git a/Assets/uGUI-2017.1/UnityEngine.UI/UI/Core/VertexModifiers/Shadow.cs b/Assets/uGUI-2017.1/UnityEngine.UI/UI/Core/VertexModifiers/Shadow.cs
new file mode 100644
index 0000000..e0a813c
--- /dev/null
+++ b/Assets/uGUI-2017.1/UnityEngine.UI/UI/Core/VertexModifiers/Shadow.cs
@@ -0,0 +1,126 @@
+using System.Collections.Generic;
+using UnityEngine;
+
+namespace UnityEngine.UI
+{
+    [AddComponentMenu("UI/Effects/Shadow", 14)]
+    public class Shadow : BaseMeshEffect
+    {
+        [SerializeField]
+        private Color m_EffectColor = new Color(0f, 0f, 0f, 0.5f);
+
+        [SerializeField]
+        private Vector2 m_EffectDistance = new Vector2(1f, -1f);
+
+        [SerializeField]
+        private bool m_UseGraphicAlpha = true;
+
+        private const float kMaxEffectDistance = 600f;
+
+        protected Shadow()
+        {}
+
+#if UNITY_EDITOR
+        protected override void OnValidate()
+        {
+            effectDistance = m_EffectDistance;
+            base.OnValidate();
+        }
+
+#endif
+
+        public Color effectColor
+        {
+            get { return m_EffectColor; }
+            set
+            {
+                m_EffectColor = value;
+                if (graphic != null)
+                    graphic.SetVerticesDirty();
+            }
+        }
+
+        public Vector2 effectDistance
+        {
+            get { return m_EffectDistance; }
+            set
+            {
+                if (value.x > kMaxEffectDistance)
+                    value.x = kMaxEffectDistance;
+                if (value.x < -kMaxEffectDistance)
+                    value.x = -kMaxEffectDistance;
+
+                if (value.y > kMaxEffectDistance)
+                    value.y = kMaxEffectDistance;
+                if (value.y < -kMaxEffectDistance)
+                    value.y = -kMaxEffectDistance;
+
+                if (m_EffectDistance == value)
+                    return;
+
+                m_EffectDistance = value;
+
+                if (graphic != null)
+                    graphic.SetVerticesDirty();
+            }
+        }
+
+        public bool useGraphicAlpha
+        {
+            get { return m_UseGraphicAlpha; }
+            set
+            {
+                m_UseGraphicAlpha = value;
+                if (graphic != null)
+                    graphic.SetVerticesDirty();
+            }
+        }
+
+		//x,y是偏移量
+        protected void ApplyShadowZeroAlloc(List<UIVertex> verts, Color32 color, int start, int end, float x, float y)
+        {
+            UIVertex vt;
+
+            var neededCapacity = verts.Count + end - start;
+            if (verts.Capacity < neededCapacity)
+                verts.Capacity = neededCapacity;
+
+            for (int i = start; i < end; ++i)
+            {
+                vt = verts[i];
+                verts.Add(vt);
+
+                Vector3 v = vt.position;
+                v.x += x;
+                v.y += y;
+                vt.position = v;
+
+                var newColor = color;
+                if (m_UseGraphicAlpha)
+                    newColor.a = (byte)((newColor.a * verts[i].color.a) / 255);
+
+                vt.color = newColor;
+                verts[i] = vt;
+            }
+        }
+
+        protected void ApplyShadow(List<UIVertex> verts, Color32 color, int start, int end, float x, float y)
+        {
+            ApplyShadowZeroAlloc(verts, color, start, end, x, y);
+        }
+
+        public override void ModifyMesh(VertexHelper vh)
+        {
+            if (!IsActive())
+                return;
+
+            var output = ListPool<UIVertex>.Get();
+            vh.GetUIVertexStream(output);
+
+            ApplyShadow(output, effectColor, 0, output.Count, effectDistance.x, effectDistance.y);
+            vh.Clear();
+            vh.AddUIVertexTriangleStream(output);
+            ListPool<UIVertex>.Release(output);
+        }
+    }
+}