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Source/Engine/UI/GUI/Brushes/GPUTextureBrush.cs

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+// Copyright (c) 2012-2020 Wojciech Figat. All rights reserved.
+
+namespace FlaxEngine.GUI
+{
+    /// <summary>
+    /// Implementation of <see cref="IBrush"/> for <see cref="FlaxEngine.GPUTexture"/>.
+    /// </summary>
+    /// <seealso cref="IBrush" />
+    public sealed class GPUTextureBrush : IBrush
+    {
+        /// <summary>
+        /// The GPU texture.
+        /// </summary>
+        [HideInEditor]
+        public GPUTexture Texture;
+
+        /// <summary>
+        /// Initializes a new instance of the <see cref="GPUTextureBrush"/> class.
+        /// </summary>
+        public GPUTextureBrush()
+        {
+        }
+
+        /// <summary>
+        /// Initializes a new instance of the <see cref="GPUTextureBrush"/> struct.
+        /// </summary>
+        /// <param name="texture">The GPU texture.</param>
+        public GPUTextureBrush(GPUTexture texture)
+        {
+            Texture = texture;
+        }
+
+        /// <inheritdoc />
+        public Vector2 Size => Texture?.Size ?? Vector2.Zero;
+
+        /// <inheritdoc />
+        public void Draw(Rectangle rect, Color color)
+        {
+            Render2D.DrawTexture(Texture, rect, color);
+        }
+    }
+}

Source/Engine/UI/GUI/Brushes/IBrush.cs

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+// Copyright (c) 2012-2020 Wojciech Figat. All rights reserved.
+
+namespace FlaxEngine.GUI
+{
+    /// <summary>
+    /// Interface that unifies input source textures, sprites, render targets, and any other brushes to be used in a more generic way.
+    /// </summary>
+    public interface IBrush
+    {
+        /// <summary>
+        /// Gets the size of the image brush in pixels (if relevant).
+        /// </summary>
+        Vector2 Size { get; }
+
+        /// <summary>
+        /// Draws the specified image using <see cref="Render2D"/> graphics backend.
+        /// </summary>
+        /// <param name="rect">The draw area rectangle.</param>
+        /// <param name="color">The color.</param>
+        void Draw(Rectangle rect, Color color);
+    }
+}

Source/Engine/UI/GUI/Brushes/LinearGradientBrush.cs

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+// Copyright (c) 2012-2020 Wojciech Figat. All rights reserved.
+
+namespace FlaxEngine.GUI
+{
+    /// <summary>
+    /// Implementation of <see cref="IBrush"/> for linear color gradient (made of 2 color).
+    /// </summary>
+    /// <seealso cref="IBrush" />
+    public sealed class LinearGradientBrush : IBrush
+    {
+        /// <summary>
+        /// The brush start color.
+        /// </summary>
+        [EditorOrder(0), ExpandGroups, Tooltip("The brush start color.")]
+        public Color StartColor;
+
+        /// <summary>
+        /// The brush end color.
+        /// </summary>
+        [EditorOrder(1), Tooltip("The brush end color.")]
+        public Color EndColor;
+
+        /// <summary>
+        /// Initializes a new instance of the <see cref="LinearGradientBrush"/> class.
+        /// </summary>
+        public LinearGradientBrush()
+        {
+            StartColor = Color.White;
+            EndColor = Color.Black;
+        }
+
+        /// <summary>
+        /// Initializes a new instance of the <see cref="LinearGradientBrush"/> struct.
+        /// </summary>
+        /// <param name="startColor">The start color.</param>
+        /// <param name="endColor">The end color.</param>
+        public LinearGradientBrush(Color startColor, Color endColor)
+        {
+            StartColor = startColor;
+            EndColor = endColor;
+        }
+
+        /// <inheritdoc />
+        public Vector2 Size => Vector2.One;
+
+        /// <inheritdoc />
+        public void Draw(Rectangle rect, Color color)
+        {
+            var startColor = StartColor * color;
+            var endColor = EndColor * color;
+            Render2D.FillRectangle(rect, startColor, startColor, endColor, endColor);
+        }
+    }
+}

Source/Engine/UI/GUI/Brushes/MaterialBrush.cs

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+// Copyright (c) 2012-2020 Wojciech Figat. All rights reserved.
+
+namespace FlaxEngine.GUI
+{
+    /// <summary>
+    /// Implementation of <see cref="IBrush"/> for <see cref="FlaxEngine.MaterialBase"/> rendering.
+    /// </summary>
+    /// <seealso cref="IBrush" />
+    public sealed class MaterialBrush : IBrush
+    {
+        /// <summary>
+        /// The material.
+        /// </summary>
+        [ExpandGroups, Tooltip("The material to use for GUI control area rendering. It must be GUI domain.")]
+        public MaterialBase Material;
+
+        /// <summary>
+        /// Initializes a new instance of the <see cref="MaterialBrush"/> class.
+        /// </summary>
+        public MaterialBrush()
+        {
+        }
+
+        /// <summary>
+        /// Initializes a new instance of the <see cref="MaterialBrush"/> struct.
+        /// </summary>
+        /// <param name="material">The material.</param>
+        public MaterialBrush(Material material)
+        {
+            Material = material;
+        }
+
+        /// <inheritdoc />
+        public Vector2 Size => Vector2.One;
+
+        /// <inheritdoc />
+        public void Draw(Rectangle rect, Color color)
+        {
+            Render2D.DrawMaterial(Material, rect, color);
+        }
+    }
+}

Source/Engine/UI/GUI/Brushes/SolidColorBrush.cs

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+// Copyright (c) 2012-2020 Wojciech Figat. All rights reserved.
+
+namespace FlaxEngine.GUI
+{
+    /// <summary>
+    /// Implementation of <see cref="IBrush"/> for single color fill.
+    /// </summary>
+    /// <seealso cref="IBrush" />
+    public sealed class SolidColorBrush : IBrush
+    {
+        /// <summary>
+        /// The brush color.
+        /// </summary>
+        [ExpandGroups, Tooltip("The brush color.")]
+        public Color Color;
+
+        /// <summary>
+        /// Initializes a new instance of the <see cref="SolidColorBrush"/> class.
+        /// </summary>
+        public SolidColorBrush()
+        {
+            Color = Color.Black;
+        }
+
+        /// <summary>
+        /// Initializes a new instance of the <see cref="SolidColorBrush"/> struct.
+        /// </summary>
+        /// <param name="color">The color.</param>
+        public SolidColorBrush(Color color)
+        {
+            Color = color;
+        }
+
+        /// <inheritdoc />
+        public Vector2 Size => Vector2.One;
+
+        /// <inheritdoc />
+        public void Draw(Rectangle rect, Color color)
+        {
+            Render2D.FillRectangle(rect, Color * color);
+        }
+    }
+}

Source/Engine/UI/GUI/Brushes/SpriteBrush.cs

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+// Copyright (c) 2012-2020 Wojciech Figat. All rights reserved.
+
+namespace FlaxEngine.GUI
+{
+    /// <summary>
+    /// Implementation of <see cref="IBrush"/> for <see cref="FlaxEngine.Sprite"/>.
+    /// </summary>
+    /// <seealso cref="IBrush" />
+    public sealed class SpriteBrush : IBrush
+    {
+        /// <summary>
+        /// The sprite.
+        /// </summary>
+        [ExpandGroups]
+        public SpriteHandle Sprite;
+
+        /// <summary>
+        /// Initializes a new instance of the <see cref="SpriteBrush"/> class.
+        /// </summary>
+        public SpriteBrush()
+        {
+        }
+
+        /// <summary>
+        /// Initializes a new instance of the <see cref="SpriteBrush"/> struct.
+        /// </summary>
+        /// <param name="sprite">The sprite.</param>
+        public SpriteBrush(SpriteHandle sprite)
+        {
+            Sprite = sprite;
+        }
+
+        /// <inheritdoc />
+        public Vector2 Size => Sprite.IsValid ? Sprite.Size : Vector2.Zero;
+
+        /// <inheritdoc />
+        public void Draw(Rectangle rect, Color color)
+        {
+            Render2D.DrawSprite(Sprite, rect, color);
+        }
+    }
+}

Source/Engine/UI/GUI/Brushes/TextureBrush.cs

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+// Copyright (c) 2012-2020 Wojciech Figat. All rights reserved.
+
+namespace FlaxEngine.GUI
+{
+    /// <summary>
+    /// Implementation of <see cref="IBrush"/> for <see cref="FlaxEngine.Texture"/>.
+    /// </summary>
+    /// <seealso cref="IBrush" />
+    public sealed class TextureBrush : IBrush
+    {
+        /// <summary>
+        /// The texture.
+        /// </summary>
+        [ExpandGroups, Tooltip("The texture asset.")]
+        public Texture Texture;
+
+        /// <summary>
+        /// Initializes a new instance of the <see cref="TextureBrush"/> class.
+        /// </summary>
+        public TextureBrush()
+        {
+        }
+
+        /// <summary>
+        /// Initializes a new instance of the <see cref="TextureBrush"/> struct.
+        /// </summary>
+        /// <param name="texture">The texture.</param>
+        public TextureBrush(Texture texture)
+        {
+            Texture = texture;
+        }
+
+        /// <inheritdoc />
+        public Vector2 Size => Texture?.Size ?? Vector2.Zero;
+
+        /// <inheritdoc />
+        public void Draw(Rectangle rect, Color color)
+        {
+            Render2D.DrawTexture(Texture, rect, color);
+        }
+    }
+}