/// Constructs an element at the specified offset.
/// May return null if no element should be constructed.
protected override InlineObjectElement ConstructMainElement(int offset)
{
Match m = FindMatch(offset);
// check whether there's a match exactly at offset
if (m.Success && m.Index == 0)
{
string scale = m.Groups[1].Value;
string laTex = m.Groups[2].Value;
BitmapImage bitmap = LaTexImageCache.Instance.LoadImage(laTex, scale);
if (bitmap != null)
{
CustomImageControl image = new CustomImageControl(offset, TextEditor);
image.Source = bitmap;
image.Width = bitmap.PixelWidth;
image.Height = bitmap.PixelHeight;
image.Cursor = Cursors.Arrow;
// Pass the length of the match to the 'documentLength' parameter
// of InlineObjectElement.
return(new InlineObjectElement(m.Length, image));
}
}
return(null);
}
private Image CreateImageControl(int offset, string scale, BitmapImage bitmap)
{
CustomImageControl image = new CustomImageControl(offset, TextEditor);
image.Source = bitmap;
double zoom = CalcZoom(bitmap, scale);
image.Width = bitmap.PixelWidth * zoom;
image.Height = bitmap.PixelHeight * zoom;
image.Cursor = Cursors.Arrow;
return(image);
}