git-svn-id: svn://svn.ijw.co.nz/svn/OpenRa@1213 993157c7-ee19-0410-b2c4-bb4e9862e678

OpenRa.Game/SheetBuilder.cs

@@ -0,0 +1,92 @@
+using System;
+using System.Collections.Generic;
+using System.Text;
+using System.Drawing;
+using BluntDirectX.Direct3D;
+using OpenRa.FileFormats;
+
+namespace OpenRa.Game
+{
+	delegate T Provider<T>();
+
+	static class SheetBuilder
+	{
+		public static void Initialize(GraphicsDevice device)
+		{
+			pageProvider = delegate { return new Sheet(new Size(512,512), device); };
+		}
+
+		public static Sprite Add(byte[] src, Size size)
+		{
+			Sprite rect = AddImage(size);
+			Util.CopyIntoChannel(rect, src);
+			return rect;
+		}
+
+		public static Sprite Add(Size size, byte paletteIndex)
+		{
+			byte[] data = new byte[size.Width * size.Height];
+			for (int i = 0; i < data.Length; i++)
+				data[i] = paletteIndex;
+
+			return Add(data, size);
+		}
+
+		static Provider<Sheet> pageProvider;
+		static Sheet current = null;
+		static int x = 0, y = 0, rowHeight = 0;
+		static TextureChannel? channel = null;
+
+		static TextureChannel? NextChannel(TextureChannel? t)
+		{
+			if (t == null)
+				return TextureChannel.Red;
+
+			switch (t.Value)
+			{
+				case TextureChannel.Red: return TextureChannel.Green;
+				case TextureChannel.Green: return TextureChannel.Blue;
+				case TextureChannel.Blue: return TextureChannel.Alpha;
+				case TextureChannel.Alpha: return null;
+
+				default: return null;
+			}
+		}
+
+		static Sprite AddImage(Size imageSize)
+		{
+			if (current == null)
+			{
+				current = pageProvider();
+				channel = NextChannel(null);
+			}
+
+			if (rowHeight == 0 || imageSize.Width + x > current.Size.Width)
+			{
+				y += rowHeight;
+				rowHeight = imageSize.Height;
+				x = 0;
+			}
+
+			if (imageSize.Height > rowHeight)
+				rowHeight = imageSize.Height;
+
+			if (y + imageSize.Height > current.Size.Height)
+			{
+
+				if (null == (channel = NextChannel(channel)))
+				{
+					current = pageProvider();
+					channel = NextChannel(channel);
+				}
+
+				x = y = rowHeight = 0;
+			}
+
+			Sprite rect = new Sprite(current, new Point(x, y), imageSize, channel.Value);
+			x += imageSize.Width;
+
+			return rect;
+		}
+	}
+}