Add a hue selector widget.

OpenRA.Game/Widgets/SliderWidget.cs

@@ -77,7 +77,7 @@ namespace OpenRA.Widgets
 		}
 
 		float ValueFromPx(int x) { return MinimumValue + (MaximumValue - MinimumValue) * (1f * x / RenderBounds.Width); }
-		int PxFromValue(float x) { return (int)(RenderBounds.Width * (x - MinimumValue) / (MaximumValue - MinimumValue)); }
+		protected int PxFromValue(float x) { return (int)(RenderBounds.Width * (x - MinimumValue) / (MaximumValue - MinimumValue)); }
 
 		public override Widget Clone() { return new SliderWidget(this); }
 

OpenRA.Mods.RA/OpenRA.Mods.RA.csproj

@@ -433,6 +433,7 @@
     <Compile Include="Widgets\Logic\SpawnSelectorTooltipLogic.cs" />
     <Compile Include="Widgets\Logic\ClientTooltipLogic.cs" />
     <Compile Include="Widgets\ColorMixerWidget.cs" />
+    <Compile Include="Widgets\HueSliderWidget.cs" />
   </ItemGroup>
   <ItemGroup>
     <ProjectReference Include="..\OpenRA.FileFormats\OpenRA.FileFormats.csproj">

OpenRA.Mods.RA/Widgets/HueSliderWidget.cs

@@ -0,0 +1,63 @@
+#region Copyright & License Information
+/*
+ * Copyright 2007-2011 The OpenRA Developers (see AUTHORS)
+ * This file is part of OpenRA, which is free software. It is made
+ * available to you under the terms of the GNU General Public License
+ * as published by the Free Software Foundation. For more information,
+ * see COPYING.
+ */
+#endregion
+
+using System;
+using System.Drawing;
+using System.Drawing.Imaging;
+using OpenRA.FileFormats;
+using OpenRA.Graphics;
+using OpenRA.Widgets;
+
+namespace OpenRA.Mods.RA.Widgets
+{
+	public class HueSliderWidget : SliderWidget
+	{
+		Bitmap hueBitmap;
+		Sprite hueSprite;
+
+		public HueSliderWidget() : base() {}
+		public HueSliderWidget(HueSliderWidget other) : base(other) {}
+
+		public override void Initialize(WidgetArgs args)
+		{
+			base.Initialize(args);
+
+			hueBitmap = new Bitmap(256, 256);
+			hueSprite = new Sprite(new Sheet(new Size(256, 256)), new Rectangle(0, 0, 256, 1), TextureChannel.Alpha);
+
+			var bitmapData = hueBitmap.LockBits(hueBitmap.Bounds(),
+				ImageLockMode.ReadWrite, PixelFormat.Format32bppArgb);
+			unsafe
+			{
+				int* c = (int*)bitmapData.Scan0;
+				for (var h = 0; h < 256; h++)
+					*(c + h) = HSLColor.FromHSV(h/255f, 1, 1).ToColor().ToArgb();
+			}
+			hueBitmap.UnlockBits(bitmapData);
+
+			hueSprite.sheet.Texture.SetData(hueBitmap);
+		}
+
+		public override void Draw()
+		{
+			if (!IsVisible())
+				return;
+
+			var ro = RenderOrigin;
+			var rb = RenderBounds;
+			Game.Renderer.RgbaSpriteRenderer.DrawSprite(hueSprite, ro, new float2(rb.Size));
+
+			var sprite = ChromeProvider.GetImage("lobby-bits", "huepicker");
+			var pos = RenderOrigin + new int2(PxFromValue(Value).Clamp(0, rb.Width-1) - sprite.bounds.Width/2, (rb.Height-sprite.bounds.Height)/2);
+			Game.Renderer.RgbaSpriteRenderer.DrawSprite(sprite, pos);
+		}
+	}
+}
+