public void AddArc(XPoint point1, XPoint point2, XSize size, double rotationAngle, bool isLargeArg, XSweepDirection sweepDirection)
{
List <XPoint> points = GeometryHelper.BezierCurveFromArc(point1, point2, size, rotationAngle, isLargeArg,
sweepDirection == XSweepDirection.Clockwise, PathStart.MoveTo1st);
int count = points.Count;
Debug.Assert((count + 2) % 3 == 0);
MoveOrLineTo(points[0].X, points[0].Y);
for (int idx = 1; idx < count; idx += 3)
{
BezierTo(points[idx].X, points[idx].Y, points[idx + 1].X, points[idx + 1].Y, points[idx + 2].X, points[idx + 2].Y, false);
}
}
/// <summary>
/// Initializes a new instance of the XRect class.
/// </summary>
public XRect(XPoint location, XSize size)
{
if (size.IsEmpty)
{
this = s_empty;
}
else
{
_x = location.X;
_y = location.Y;
_width = size.Width;
_height = size.Height;
}
}
/// <summary>
/// Measure string directly from font data.
/// </summary>
public static XSize MeasureString(string text, XFont font, XStringFormat stringFormat)
{
XSize size = new XSize();
OpenTypeDescriptor descriptor = FontDescriptorCache.GetOrCreateDescriptorFor(font) as OpenTypeDescriptor;
if (descriptor != null)
{
// Height is the sum of ascender and descender.
size.Height = (descriptor.Ascender + descriptor.Descender) * font.Size / font.UnitsPerEm;
Debug.Assert(descriptor.Ascender > 0);
bool symbol = descriptor.FontFace.cmap.symbol;
int length = text.Length;
int width = 0;
for (int idx = 0; idx < length; idx++)
{
char ch = text[idx];
// HACK: Unclear what to do here.
if (ch < 32)
{
continue;
}
if (symbol)
{
// Remap ch for symbol fonts.
ch = (char)(ch | (descriptor.FontFace.os2.usFirstCharIndex & 0xFF00)); // @@@ refactor
// Used | instead of + because of: http://PdfSharpCore.codeplex.com/workitem/15954
}
int glyphIndex = descriptor.CharCodeToGlyphIndex(ch);
width += descriptor.GlyphIndexToWidth(glyphIndex);
}
// What? size.Width = width * font.Size * (font.Italic ? 1 : 1) / descriptor.UnitsPerEm;
size.Width = width * font.Size / descriptor.UnitsPerEm;
// Adjust bold simulation.
if ((font.GlyphTypeface.StyleSimulations & XStyleSimulations.BoldSimulation) == XStyleSimulations.BoldSimulation)
{
// Add 2% of the em-size for each character.
// Unsure how to deal with white space. Currently count as regular character.
size.Width += length * font.Size * Const.BoldEmphasis;
}
}
Debug.Assert(descriptor != null, "No OpenTypeDescriptor.");
return(size);
}
/// <summary>
/// Initializes a new instance of the <see cref="XForm"/> class that represents a page of a PDF document.
/// </summary>
/// <param name="document">The PDF document.</param>
/// <param name="size">The size of the page.</param>
public XForm(PdfDocument document, XSize size)
: this(document, new XRect(0, 0, size.Width, size.Height))
{
////if (size.width < 1 || size.height < 1)
//// throw new ArgumentNullException("size", "The size of the XPdfForm is to small.");
////// I must tie the XPdfForm to a document immediately, because otherwise I would have no place where
////// to store the resources.
////if (document == null)
//// throw new ArgumentNullException("document", "An XPdfForm template must be associated with a document.");
////_formState = FormState.Created;
////_document = document;
////pdfForm = new PdfFormXObject(document, this);
////templateSize = size;
////PdfRectangle rect = new PdfRectangle(new XPoint(), size);
////pdfForm.Elements.SetRectangle(PdfFormXObject.Keys.BBox, rect);
}
/// <summary>
/// Parses the size from a string.
/// </summary>
public static XSize Parse(string source)
{
XSize empty;
CultureInfo cultureInfo = CultureInfo.InvariantCulture;
TokenizerHelper helper = new TokenizerHelper(source, cultureInfo);
string str = helper.NextTokenRequired();
if (str == "Empty")
{
empty = Empty;
}
else
{
empty = new XSize(Convert.ToDouble(str, cultureInfo), Convert.ToDouble(helper.NextTokenRequired(), cultureInfo));
}
helper.LastTokenRequired();
return(empty);
}
/// <summary>
/// Returns the rectangle that results from expanding the specified rectangle by the specified Size, in all directions.
/// </summary>
public static XRect Inflate(XRect rect, XSize size)
{
rect.Inflate(size.Width, size.Height);
return(rect);
}
/// <summary>
/// Expands the rectangle by using the specified Size, in all directions.
/// </summary>
public void Inflate(XSize size)
{
Inflate(size.Width, size.Height);
}
/// <summary>
/// Creates between 1 and 5 Béziers curves from parameters specified like in WPF.
/// </summary>
public static List <XPoint> BezierCurveFromArc(XPoint point1, XPoint point2, XSize size,
double rotationAngle, bool isLargeArc, bool clockwise, PathStart pathStart)
{
// See also http://www.charlespetzold.com/blog/blog.xml from January 2, 2008:
// http://www.charlespetzold.com/blog/2008/01/Mathematics-of-ArcSegment.html
double δx = size.Width;
double δy = size.Height;
Debug.Assert(δx * δy > 0);
double factor = δy / δx;
bool isCounterclockwise = !clockwise;
// Adjust for different radii and rotation angle.
XMatrix matrix = new XMatrix();
matrix.RotateAppend(-rotationAngle);
matrix.ScaleAppend(δy / δx, 1);
XPoint pt1 = matrix.Transform(point1);
XPoint pt2 = matrix.Transform(point2);
// Get info about chord that connects both points.
XPoint midPoint = new XPoint((pt1.X + pt2.X) / 2, (pt1.Y + pt2.Y) / 2);
XVector vect = pt2 - pt1;
double halfChord = vect.Length / 2;
// Get vector from chord to center.
XVector vectRotated;
// (comparing two Booleans here!)
if (isLargeArc == isCounterclockwise)
{
vectRotated = new XVector(-vect.Y, vect.X);
}
else
{
vectRotated = new XVector(vect.Y, -vect.X);
}
vectRotated.Normalize();
// Distance from chord to center.
double centerDistance = Math.Sqrt(δy * δy - halfChord * halfChord);
if (double.IsNaN(centerDistance))
{
centerDistance = 0;
}
// Calculate center point.
XPoint center = midPoint + centerDistance * vectRotated;
// Get angles from center to the two points.
double α = Math.Atan2(pt1.Y - center.Y, pt1.X - center.X);
double β = Math.Atan2(pt2.Y - center.Y, pt2.X - center.X);
// (another comparison of two Booleans!)
if (isLargeArc == (Math.Abs(β - α) < Math.PI))
{
if (α < β)
{
α += 2 * Math.PI;
}
else
{
β += 2 * Math.PI;
}
}
// Invert matrix for final point calculation.
matrix.Invert();
double sweepAngle = β - α;
// Let the algorithm of GDI+ DrawArc to Bézier curves do the rest of the job
return(BezierCurveFromArc(center.X - δx * factor, center.Y - δy, 2 * δx * factor, 2 * δy,
α / Calc.Deg2Rad, sweepAngle / Calc.Deg2Rad, pathStart, ref matrix));
}
static XSize()
{
s_empty = CreateEmptySize();
}
/// <summary>
/// Indicates whether this instance and a specified size are equal.
/// </summary>
public bool Equals(XSize value)
{
return(Equals(this, value));
}
