Add has border and border thickness options.

Source/Engine/UI/GUI/Common/Button.cs

@@ -84,17 +84,23 @@ namespace FlaxEngine.GUI
         /// </summary>
         [EditorDisplay("Border Style"), EditorOrder(2010), ExpandGroups]
         public bool HasBorder { get; set; } = true;
+        
+        /// <summary>
+        /// Gets or sets the border thickness.
+        /// </summary>
+        [EditorDisplay("Border Style"), EditorOrder(2011), Limit(0)]
+        public float BorderThickness { get; set; } = 1.0f;
 
         /// <summary>
         /// Gets or sets the color of the border.
         /// </summary>
-        [EditorDisplay("Border Style"), EditorOrder(2011), ExpandGroups]
+        [EditorDisplay("Border Style"), EditorOrder(2012)]
         public Color BorderColor { get; set; }
 
         /// <summary>
         /// Gets or sets the border color when button is highlighted.
         /// </summary>
-        [EditorDisplay("Border Style"), EditorOrder(2012)]
+        [EditorDisplay("Border Style"), EditorOrder(2013)]
         public Color BorderColorHighlighted { get; set; }
 
         /// <summary>
@@ -252,7 +258,7 @@ namespace FlaxEngine.GUI
             else
                 Render2D.FillRectangle(clientRect, backgroundColor);
             if (HasBorder)
-                Render2D.DrawRectangle(clientRect, borderColor);
+                Render2D.DrawRectangle(clientRect, borderColor, BorderThickness);
 
             // Draw text
             Render2D.DrawText(_font?.GetFont(), TextMaterial, _text, clientRect, textColor, TextAlignment.Center, TextAlignment.Center);

Source/Engine/UI/GUI/Common/CheckBox.cs

@@ -107,17 +107,29 @@ namespace FlaxEngine.GUI
                 CacheBox();
             }
         }
+        
+        /// <summary>
+        /// Gets or sets whether to have a border.
+        /// </summary>
+        [EditorDisplay("Border Style"), EditorOrder(2010), Tooltip("Whether to have a border."), ExpandGroups]
+        public bool HasBorder { get; set; } = true;
+        
+        /// <summary>
+        /// Gets or sets the border thickness.
+        /// </summary>
+        [EditorDisplay("Border Style"), EditorOrder(2011), Tooltip("The thickness of the border."), Limit(0)]
+        public float BorderThickness { get; set; } = 1.0f;
 
         /// <summary>
         /// Gets or sets the color of the border.
         /// </summary>
-        [EditorDisplay("Border Style"), EditorOrder(2010), ExpandGroups]
+        [EditorDisplay("Border Style"), EditorOrder(2012)]
         public Color BorderColor { get; set; }
 
         /// <summary>
         /// Gets or sets the border color when checkbox is hovered.
         /// </summary>
-        [EditorDisplay("Border Style"), EditorOrder(2011)]
+        [EditorDisplay("Border Style"), EditorOrder(2013)]
         public Color BorderColorHighlighted { get; set; }
 
         /// <summary>
@@ -221,12 +233,15 @@ namespace FlaxEngine.GUI
             bool enabled = EnabledInHierarchy;
 
             // Border
-            Color borderColor = BorderColor;
+            if (HasBorder)
-            if (!enabled)
+            {
-                borderColor *= 0.5f;
+                Color borderColor = BorderColor;
-            else if (_isPressed || _mouseOverBox || IsNavFocused)
+                if (!enabled)
-                borderColor = BorderColorHighlighted;
+                    borderColor *= 0.5f;
-            Render2D.DrawRectangle(_box.MakeExpanded(-2.0f), borderColor);
+                else if (_isPressed || _mouseOverBox || IsNavFocused)
+                    borderColor = BorderColorHighlighted;
+                Render2D.DrawRectangle(_box.MakeExpanded(-2.0f), borderColor, BorderThickness);
+            }
 
             // Icon
             if (_state != CheckBoxState.Default)

Source/Engine/UI/GUI/Common/TextBox.cs

@@ -155,7 +155,8 @@ namespace FlaxEngine.GUI
             if (IsMouseOver || IsNavFocused)
                 backColor = BackgroundSelectedColor;
             Render2D.FillRectangle(rect, backColor);
-            Render2D.DrawRectangle(rect, IsFocused ? BorderSelectedColor : BorderColor);
+            if (HasBorder)
+                Render2D.DrawRectangle(rect, IsFocused ? BorderSelectedColor : BorderColor, BorderThickness);
 
             // Apply view offset and clip mask
             if (ClipText)

Source/Engine/UI/GUI/Common/TextBoxBase.cs

@@ -270,16 +270,28 @@ namespace FlaxEngine.GUI
         [EditorDisplay("Background Style"), EditorOrder(2002), Tooltip("The speed of the selection background flashing animation.")]
         public float BackgroundSelectedFlashSpeed { get; set; } = 6.0f;
 
+        /// <summary>
+        /// Gets or sets whether to have a border.
+        /// </summary>
+        [EditorDisplay("Border Style"), EditorOrder(2010), Tooltip("Whether to have a border."), ExpandGroups]
+        public bool HasBorder { get; set; } = true;
+        
+        /// <summary>
+        /// Gets or sets the border thickness.
+        /// </summary>
+        [EditorDisplay("Border Style"), EditorOrder(2011), Tooltip("The thickness of the border."), Limit(0)]
+        public float BorderThickness { get; set; } = 1.0f;
+        
         /// <summary>
         /// Gets or sets the color of the border (Transparent if not used).
         /// </summary>
-        [EditorDisplay("Border Style"), EditorOrder(2010), Tooltip("The color of the border (Transparent if not used)."), ExpandGroups]
+        [EditorDisplay("Border Style"), EditorOrder(2012), Tooltip("The color of the border (Transparent if not used).")]
         public Color BorderColor { get; set; }
 
         /// <summary>
         /// Gets or sets the color of the border when control is focused (Transparent if not used).
         /// </summary>
-        [EditorDisplay("Border Style"), EditorOrder(2011), Tooltip("The color of the border when control is focused (Transparent if not used)")]
+        [EditorDisplay("Border Style"), EditorOrder(2013), Tooltip("The color of the border when control is focused (Transparent if not used)")]
         public Color BorderSelectedColor { get; set; }
 
         /// <summary>