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Source/Engine/Render2D/SpriteAtlas.cs

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+// Copyright (c) 2012-2020 Wojciech Figat. All rights reserved.
+
+using System;
+
+namespace FlaxEngine
+{
+    partial struct SpriteHandle
+    {
+        /// <summary>
+        /// Invalid sprite handle.
+        /// </summary>
+        public static SpriteHandle Invalid;
+
+        /// <summary>
+        /// Initializes a new instance of the <see cref="Sprite"/> struct.
+        /// </summary>
+        /// <param name="atlas">The atlas.</param>
+        /// <param name="index">The index.</param>
+        public SpriteHandle(SpriteAtlas atlas, int index)
+        {
+            Atlas = atlas;
+            Index = index;
+        }
+
+        /// <summary>
+        /// Returns true if sprite is valid.
+        /// </summary>
+        public bool IsValid => Atlas != null && Index != -1;
+
+        /// <summary>
+        /// Gets or sets the sprite name.
+        /// </summary>
+        [NoSerialize]
+        public string Name
+        {
+            get
+            {
+                if (Atlas == null)
+                    throw new InvalidOperationException("Cannot use invalid sprite.");
+                return Atlas.GetSprite(Index).Name;
+            }
+            set
+            {
+                if (Atlas == null)
+                    throw new InvalidOperationException("Cannot use invalid sprite.");
+                var sprite = Atlas.GetSprite(Index);
+                sprite.Name = value;
+                Atlas.SetSprite(Index, ref sprite);
+            }
+        }
+
+        /// <summary>
+        /// Gets or sets the sprite location (in pixels).
+        /// </summary>
+        [NoSerialize]
+        public Vector2 Location
+        {
+            get => Area.Location * Atlas.Size;
+            set
+            {
+                var area = Area;
+                area.Location = value / Atlas.Size;
+                Area = area;
+            }
+        }
+
+        /// <summary>
+        /// Gets or sets the sprite size (in pixels).
+        /// </summary>
+        [NoSerialize]
+        public Vector2 Size
+        {
+            get => Area.Size * Atlas.Size;
+            set
+            {
+                var area = Area;
+                area.Size = value / Atlas.Size;
+                Area = area;
+            }
+        }
+
+        /// <summary>
+        /// Gets or sets the sprite area in atlas (in normalized atlas coordinates [0;1]).
+        /// </summary>
+        [NoSerialize]
+        public Rectangle Area
+        {
+            get
+            {
+                if (Atlas == null)
+                    throw new InvalidOperationException("Cannot use invalid sprite.");
+                return Atlas.GetSprite(Index).Area;
+            }
+            set
+            {
+                if (Atlas == null)
+                    throw new InvalidOperationException("Cannot use invalid sprite.");
+                var sprite = Atlas.GetSprite(Index);
+                sprite.Area = value;
+                Atlas.SetSprite(Index, ref sprite);
+            }
+        }
+    }
+}