// Copyright (c) AlphaSierraPapa for the SharpDevelop Team (for details please see \doc\copyright.txt)
// This code is distributed under the GNU LGPL (for details please see \doc\license.txt)
using System;
using System.Windows;
using System.Windows.Media;
using ICSharpCode.AvalonEdit.Rendering;
using ICSharpCode.AvalonEdit.Utils;
namespace ICSharpCode.AvalonEdit.Rendering
{
/// <summary>
/// Renders a ruler at a certain column.
/// </summary>
sealed class ColumnRulerRenderer : IBackgroundRenderer
{
Pen pen;
int column;
TextView textView;
public static readonly Color DefaultForeground = Colors.LightGray;
public ColumnRulerRenderer(TextView textView)
{
if (textView == null)
throw new ArgumentNullException("textView");
this.pen = new Pen(new SolidColorBrush(DefaultForeground), 1);
this.pen.Freeze();
this.textView = textView;
this.textView.BackgroundRenderers.Add(this);
}
public KnownLayer Layer {
get { return KnownLayer.Background; }
}
public void SetRuler(int column, Pen pen)
{
if (this.column != column) {
this.column = column;
textView.InvalidateLayer(this.Layer);
}
if (this.pen != pen) {
this.pen = pen;
textView.InvalidateLayer(this.Layer);
}
}
public void Draw(TextView textView, System.Windows.Media.DrawingContext drawingContext)
{
if (column < 1) return;
double offset = textView.WideSpaceWidth * column;
Size pixelSize = PixelSnapHelpers.GetPixelSize(textView);
double markerXPos = PixelSnapHelpers.PixelAlign(offset, pixelSize.Width);
markerXPos -= textView.ScrollOffset.X;
Point start = new Point(markerXPos, 0);
Point end = new Point(markerXPos, Math.Max(textView.DocumentHeight, textView.ActualHeight));
drawingContext.DrawLine(pen, start, end);
}
}
}