Added Clear() method to all classes that contain caches.

Implemented IDisposable interface on the TextPrinter and all relevant classes.

Source/Utilities/Graphics/ITextPrinter.cs

@@ -15,7 +15,7 @@ namespace OpenTK.Graphics
     /// <summary>
     /// Defines the interface for a TextPrinter.
     /// </summary>
-    public interface ITextPrinter
+    public interface ITextPrinter : IDisposable
     {
         void Begin();
         void End();

Source/Utilities/Graphics/Text/GL1TextOutputProvider.cs

@@ -39,8 +39,8 @@ namespace OpenTK.Graphics.Text
         // Triangle lists, sorted by texture.
         Dictionary<Texture2D, List<Vector2>> active_lists = new Dictionary<Texture2D, List<Vector2>>();
         Queue<List<Vector2>> inactive_lists = new Queue<List<Vector2>>();
-        float[] viewport = new float[4];
+
-        bool legacy_mode = false;
+        bool disposed;
 
         #endregion
 
@@ -118,10 +118,12 @@ namespace OpenTK.Graphics.Text
                 
                 key.Bind();
 
-                if (!legacy_mode)
+                //if (!legacy_mode)
-                {
+                //{
-                    GL.Scale(2.0 / (viewport[2] - viewport[0]), -2.0 / (viewport[3] - viewport[1]), 1);
+                //    GL.PushMatrix();
-                }
+                //    GL.GetFloat(GetPName.Viewport, viewport);
+                //    GL.Scale(2.0 / (viewport[2] - viewport[0]), -2.0 / (viewport[3] - viewport[1]), 1);
+                //}
 
                 SetColor(color);
 
@@ -134,6 +136,9 @@ namespace OpenTK.Graphics.Text
                 }
 
                 GL.End();
+
+                //if (!legacy_mode)
+                //    GL.PopMatrix();
             }
 
             // Clean layout
@@ -150,47 +155,11 @@ namespace OpenTK.Graphics.Text
 
         #endregion
 
-        #region Begin
+        #region Clear
 
-        [Obsolete]
+        public void Clear()
-        public void Begin()
         {
-            GraphicsContext.Assert();
+            Cache.Clear();
-
-            legacy_mode = true;
-
-            GL.GetFloat(GetPName.Viewport, viewport);
-
-            // Prepare to draw text. We want pixel perfect precision, so we setup a 2D mode,
-            // with size equal to the window (in pixels). 
-            // While we could also render text in 3D mode, it would be very hard to get
-            // pixel-perfect precision.
-            GL.MatrixMode(MatrixMode.Projection);
-            GL.PushMatrix();
-            GL.LoadIdentity();
-            GL.Ortho(viewport[0], viewport[2], viewport[3], viewport[1], -1.0, 1.0);
-
-            GL.MatrixMode(MatrixMode.Modelview);
-            GL.PushMatrix();
-            GL.LoadIdentity();
-        }
-
-        #endregion
-
-        #region End
-
-        [Obsolete]
-        public void End()
-        {
-            GraphicsContext.Assert();
-
-            legacy_mode = false;
-
-            GL.MatrixMode(MatrixMode.Modelview);
-            GL.PopMatrix();
-
-            GL.MatrixMode(MatrixMode.Projection);
-            GL.PopMatrix();
         }
 
         #endregion
@@ -220,5 +189,18 @@ namespace OpenTK.Graphics.Text
         }
 
         #endregion
+
+        #region IDisposable Members
+
+        public void Dispose()
+        {
+            if (!disposed)
+            {
+                Cache.Dispose();
+                disposed = true;
+            }
+        }
+
+        #endregion
     }
 }

Source/Utilities/Graphics/Text/GdiPlusGlyphRasterizer .cs

@@ -35,7 +35,7 @@ using OpenTK.Platform;
 
 namespace OpenTK.Graphics.Text
 {
-    class GdiPlusGlyphRasterizer : IGlyphRasterizer
+    sealed class GdiPlusGlyphRasterizer : IGlyphRasterizer
     {
         #region Fields
 
@@ -129,6 +129,11 @@ namespace OpenTK.Graphics.Text
 
         #endregion
 
+        public void Clear()
+        {
+            block_cache.Clear();
+        }
+
         #endregion
 
         #region Private Members

Source/Utilities/Graphics/Text/GlyphCache.cs

@@ -41,10 +41,14 @@ namespace OpenTK.Graphics.Text
 
         public abstract CachedGlyphInfo this[Glyph glyph] { get; }
 
+        public abstract void Clear();
+
+        public abstract void Dispose();
+
         #endregion
     }
 
-    class GlyphCache<T> : GlyphCache where T : Texture2D
+    sealed class GlyphCache<T> : GlyphCache where T : Texture2D
     {
         #region Fields
 
@@ -53,6 +57,8 @@ namespace OpenTK.Graphics.Text
 
         Dictionary<Glyph, CachedGlyphInfo> cached_glyphs = new Dictionary<Glyph, CachedGlyphInfo>();
 
+        bool disposed;
+
         const int SheetWidth = 512, SheetHeight = 512;
 
         #endregion
@@ -106,6 +112,13 @@ namespace OpenTK.Graphics.Text
                 return cached_glyphs[glyph];
             }
         }
+        public override void Clear()
+        {
+            for (int i = 0; i < sheets.Count; i++)
+                sheets[i].Dispose();
+
+            sheets.Clear();
+        }
 
         #endregion
 
@@ -125,5 +138,18 @@ namespace OpenTK.Graphics.Text
         }
 
         #endregion
+
+        #region IDisposable Members
+
+        public override void Dispose()
+        {
+             if (!disposed)
+            {
+                Clear();
+                disposed = true;
+             }
+        }
+
+        #endregion
     }
 }

Source/Utilities/Graphics/Text/GlyphSheet.cs

@@ -32,13 +32,15 @@ using System.Drawing;
 
 namespace OpenTK.Graphics.Text
 {
-    class GlyphSheet<T> where T : Texture2D
+    class GlyphSheet<T> : IDisposable where T : Texture2D
     {
         #region Fields
 
         readonly T texture;
         readonly GlyphPacker packer;
 
+        bool disposed;
+
         #endregion
 
         #region Constructors
@@ -46,7 +48,9 @@ namespace OpenTK.Graphics.Text
         public GlyphSheet(int width, int height)
         {
             texture = (T)typeof(T).GetConstructor(new Type[] { typeof(int), typeof(int) }).Invoke(new object[] { width, height });
-             packer = new GlyphPacker(width, height);
+            //texture.MagnificationFilter = TextureMagFilter.Nearest;
+            //texture.MinificationFilter = TextureMinFilter.Nearest;
+            packer = new GlyphPacker(width, height);
         }
 
         #endregion
@@ -64,5 +68,18 @@ namespace OpenTK.Graphics.Text
         }
 
         #endregion
+
+        #region IDisposable Members
+
+        public void Dispose()
+        {
+            if (!disposed)
+            {
+                texture.Dispose();
+                disposed = true;
+            }
+        }
+
+        #endregion
     }
 }

Source/Utilities/Graphics/Text/IGlyphCache.cs

@@ -25,12 +25,15 @@
 //
 #endregion
 
+using System;
+
 namespace OpenTK.Graphics.Text
 {
-    interface IGlyphCache
+    interface IGlyphCache : IDisposable
     {
         void Add(Glyph glyph, IGlyphRasterizer rasterizer, TextQuality quality);
         bool Contains(Glyph glyph);
         CachedGlyphInfo this[Glyph glyph] { get; }
+        void Clear();
     }
 }

Source/Utilities/Graphics/Text/IGlyphRasterizer.cs

@@ -40,5 +40,6 @@ namespace OpenTK.Graphics.Text
         Bitmap Rasterize(Glyph glyph, TextQuality quality);
         TextExtents MeasureText(TextBlock block);
         TextExtents MeasureText(TextBlock block, TextQuality quality);
+        void Clear();
     }
 }

Source/Utilities/Graphics/Text/ITextOutputProvider.cs

@@ -32,10 +32,9 @@ using System.Drawing;
 
 namespace OpenTK.Graphics.Text
 {
-    interface ITextOutputProvider
+    interface ITextOutputProvider : IDisposable
     {
         void Print(TextBlock block, Color color, IGlyphRasterizer rasterizer);
-        void Begin();
+        void Clear();
-        void End();
     }
 }

Source/Utilities/Graphics/TextPrinter.cs

@@ -34,6 +34,8 @@ namespace OpenTK.Graphics
         ITextOutputProvider text_output;
         TextQuality text_quality;
 
+        bool disposed;
+
         #endregion
 
         #region Constructors
@@ -58,32 +60,6 @@ namespace OpenTK.Graphics
 
         #region ITextPrinter Members
 
-        #region public void Begin()
-
-        /// <summary>
-        /// Sets up OpenGL state for drawing text.
-        /// </summary>
-        [Obsolete]
-        public void Begin()
-        {
-            TextOutput.Begin();
-        }
-
-        #endregion
-
-        #region public void End()
-
-        /// <summary>
-        /// Restores OpenGL state.
-        /// </summary>
-        [Obsolete]
-        public void End()
-        {
-            TextOutput.End();
-        }
-
-        #endregion
-
         #region Print
 
         public void Print(string text, Font font, Color color)
@@ -98,10 +74,13 @@ namespace OpenTK.Graphics
 
         public void Print(string text, Font font, Color color, SizeF size, TextPrinterOptions options)
         {
+            if (disposed)
+                throw new ObjectDisposedException(this.GetType().ToString());
+
             if (!ValidateParameters(text, font, size))
                 return;
 
-            text_output.Print(new TextBlock(text, font, options, size), color, Rasterizer);
+            TextOutput.Print(new TextBlock(text, font, options, size), color, Rasterizer);
         }
 
         #endregion
@@ -120,6 +99,9 @@ namespace OpenTK.Graphics
 
         public TextExtents Measure(string text, Font font, SizeF size, TextPrinterOptions options)
         {
+            if (disposed)
+                throw new ObjectDisposedException(this.GetType().ToString());
+
             if (!ValidateParameters(text, font, size))
                 return TextExtents.Empty;
 
@@ -132,14 +114,64 @@ namespace OpenTK.Graphics
 
         public void Clear()
         {
-            //glyph_cache.Clear();
+            if (disposed)
-            throw new NotImplementedException();
+                throw new ObjectDisposedException(this.GetType().ToString());
+
+            TextOutput.Clear();
+            Rasterizer.Clear();
         }
 
         #endregion
 
         #region Obsolete
 
+        /// <summary>
+        /// Sets up OpenGL state for drawing text.
+        /// </summary>
+        [Obsolete]
+        public void Begin()
+        {
+            if (disposed)
+                throw new ObjectDisposedException(this.GetType().ToString());
+
+            GraphicsContext.Assert();
+
+            float[] viewport = new float[4];
+
+            GL.GetFloat(GetPName.Viewport, viewport);
+
+            // Prepare to draw text. We want pixel perfect precision, so we setup a 2D mode,
+            // with size equal to the window (in pixels). 
+            // While we could also render text in 3D mode, it would be very hard to get
+            // pixel-perfect precision.
+            GL.MatrixMode(MatrixMode.Projection);
+            GL.PushMatrix();
+            GL.LoadIdentity();
+            GL.Ortho(viewport[0], viewport[2], viewport[3], viewport[1], -1.0, 1.0);
+
+            GL.MatrixMode(MatrixMode.Modelview);
+            GL.PushMatrix();
+            GL.LoadIdentity();
+        }
+
+        /// <summary>
+        /// Restores OpenGL state.
+        /// </summary>
+        [Obsolete]
+        public void End()
+        {
+            if (disposed)
+                throw new ObjectDisposedException(this.GetType().ToString());
+
+            GraphicsContext.Assert();
+
+            GL.MatrixMode(MatrixMode.Modelview);
+            GL.PopMatrix();
+
+            GL.MatrixMode(MatrixMode.Projection);
+            GL.PopMatrix();
+        }
+
         [Obsolete("Use TextPrinter.Print instead")]
         public void Draw(TextHandle handle)
         {
@@ -204,5 +236,18 @@ namespace OpenTK.Graphics
         }
 
         #endregion
+
+        #region IDisposable Members
+
+        public void Dispose()
+        {
+            if (!disposed)
+            {
+                TextOutput.Dispose();
+                disposed = true;
+            }
+        }
+
+        #endregion
     }
 }