private void Parse_MouseDown(object sender, MouseButtonEventArgs e)
{
canvasString = InputTextBox.Text;
canvasString = canvasString.Replace(" ", "");
if (canvasString == "")
{
imageCanvas.Source = null;
return;
}
if (ParseFormula())
{
imageCanvas.Source = null;
return;
}
TexFormula formula = Parse_Formula(canvasString);
if (formula == null)
{
return;
}
TexRenderer renderer = formula.GetRenderer(TexStyle.Display, 20.0, "Arial");
savePng = renderer.RenderToBitmap(0.0, 0.0);
imageCanvas.Source = savePng;
}
/// <summary>
/// Renders a formula to a bitmap.
/// </summary>
/// <param name="formulaRenderer">The formula renderer.</param>
/// <param name="x">The x offset of the formula.</param>
/// <param name="y">The y offset.
/// If y is negative, the distance of top to text does not change, and the distance from bottom to text changes by Ceiling(-y), because Ceiling(-y) pixel lines are added to the image.
/// That means, that if looked from the bottom of the image, the formula shifts upwardes, but in integer pixel steps.
/// If y is positive, the distance of top of image to text changes by y. Because Ceiling(y) pixel lines are added to the image,
/// the distance from bottom of the image to text changes by [Ceiling(y)-y], i.e. the shift is 0 for y==0, 1 for y==(0+epsilon), and 0 again for y==1.
/// That means, if measured from the bottom of the image, the formula shifts upwards, but maximal by 1 pixel.
/// </param>
/// <param name="dpiResolution">The resolution of the image in dpi. If not sure, use 96 dpi.</param>
/// <returns>The bitmap souce that represents the formula.</returns>
public static (BitmapSource bitmapSource, int width96thInch, int heigth96thInch) RenderToBitmap(TexRenderer formulaRenderer, double x, double y, double dpiResolution)
{
var visual = new DrawingVisual();
using (var drawingContext = visual.RenderOpen())
{
// Note that argument y in Render measures from the top. Thus is y is positive, this shifts the text down.
formulaRenderer.Render(drawingContext, x, Math.Max(0, y)); // if y negative, then we don't change y, because we measure relative to the upper edge of the image. Only if y is positive, we translate the formula downwards.
}
var width = (int)Math.Ceiling(formulaRenderer.RenderSize.Width);
var height = (int)Math.Ceiling(formulaRenderer.RenderSize.Height);
height += (int)Math.Ceiling(Math.Abs(y));
var relativeResolution = dpiResolution / 96.0;
var bitmap = new RenderTargetBitmap((int)(relativeResolution * width), (int)(relativeResolution * height), (int)(relativeResolution * 96), (int)(relativeResolution * 96), PixelFormats.Default);
bitmap.Render(visual);
return(bitmap, width, height);
}
private Rect ExtractAreaOfLine(float scale, TexRenderer f)
{
return(new Rect(f.X * scale, (f.Y * scale - lineDepth), f.Width * scale, lineHeight));
}
