source: stable/HeuristicLab.ExtLibs/HeuristicLab.AvalonEdit/5.0.1/AvalonEdit-5.0.1/Rendering/TextViewCachedElements.cs @ 14706

// Copyright (c) 2014 AlphaSierraPapa for the SharpDevelop Team
// 
// Permission is hereby granted, free of charge, to any person obtaining a copy of this
// software and associated documentation files (the "Software"), to deal in the Software
// without restriction, including without limitation the rights to use, copy, modify, merge,
// publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons
// to whom the Software is furnished to do so, subject to the following conditions:
// 
// The above copyright notice and this permission notice shall be included in all copies or
// substantial portions of the Software.
// 
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED,
// INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR
// PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE
// FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
// OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
// DEALINGS IN THE SOFTWARE.

using System;
using System.Collections.Generic;
using System.Windows.Media;
using System.Windows.Media.TextFormatting;
using ICSharpCode.AvalonEdit.Utils;

namespace ICSharpCode.AvalonEdit.Rendering
{
  sealed class TextViewCachedElements : IDisposable
  {
    TextFormatter formatter;
    Dictionary<string, TextLine> nonPrintableCharacterTexts;
    
    public TextLine GetTextForNonPrintableCharacter(string text, ITextRunConstructionContext context)
    {
      if (nonPrintableCharacterTexts == null)
        nonPrintableCharacterTexts = new Dictionary<string, TextLine>();
      TextLine textLine;
      if (!nonPrintableCharacterTexts.TryGetValue(text, out textLine)) {
        var p = new VisualLineElementTextRunProperties(context.GlobalTextRunProperties);
        p.SetForegroundBrush(context.TextView.NonPrintableCharacterBrush);
        if (formatter == null)
          formatter = TextFormatterFactory.Create(context.TextView);
        textLine = FormattedTextElement.PrepareText(formatter, text, p);
        nonPrintableCharacterTexts[text] = textLine;
      }
      return textLine;
    }
    
    public void Dispose()
    {
      if (nonPrintableCharacterTexts != null) {
        foreach (TextLine line in nonPrintableCharacterTexts.Values)
          line.Dispose();
      }
      if (formatter != null)
        formatter.Dispose();
    }
  }
}