public static ShxArc FromArcCommand(ShxGlyphCommandArc a, ref ShxPoint lastPoint)
{
var offset = new ShxPoint(a.XDisplacement, a.YDisplacement);
var chordLength = offset.Length;
var perpendicularHeight = Math.Abs(a.Bulge) * chordLength / 254.0;
var isCounterClockwise = a.Bulge >= 0.0;
var perpendicularVector = offset.Perpendicular.Normalized * perpendicularHeight;
var startPoint = lastPoint;
var midPoint = startPoint + offset.MidPoint + perpendicularVector;
var endPoint = startPoint + offset;
lastPoint = endPoint;
var radius = (perpendicularHeight / 2.0) + (chordLength * chordLength / (8.0 * perpendicularHeight));
var center = midPoint - (perpendicularVector.Normalized * radius);
var arcAngle = 2.0 * Math.Asin(chordLength / (2.0 * radius));
if (!isCounterClockwise)
{
var temp = startPoint;
startPoint = endPoint;
endPoint = temp;
}
var startPointVector = startPoint - center;
var startAngle = Math.Atan2(startPointVector.Y, startPointVector.X);
var endPointVector = endPoint - center;
var endAngle = Math.Atan2(endPointVector.Y, endPointVector.X);
var arc = new ShxArc(center, radius, startAngle, endAngle);
return(arc);
}
public void PopPoint()
{
if (_pointStack.Count > 0)
{
// TODO: some fonts contain a single pop instruction for the character '\r'
_lastPoint = _pointStack.Pop();
}
}
public void ProcessNewPosition(ShxPoint delta)
{
var nextPoint = _lastPoint + (delta * _vectorScale);
if (_isDrawing)
{
Paths.Add(new ShxLine(_lastPoint, nextPoint));
}
_lastPoint = nextPoint;
}
public static ShxArc FromArcCommand(ShxGlyphCommandOctantArc a, ref ShxPoint lastPoint)
{
var octantCount = a.OctantCount;
if (octantCount == 0)
{
// 0 means full circle
octantCount = 8;
}
var endingOctant = a.IsCounterClockwise
? a.StartingOctant + octantCount
: a.StartingOctant - octantCount;
while (endingOctant < 0)
{
endingOctant += 8;
}
var startVector = OctantArcVectors[a.StartingOctant % 8] * a.Radius;
var endVector = OctantArcVectors[endingOctant % 8] * a.Radius;
if (a.OctantCount < 0)
{
var temp = startVector;
startVector = endVector;
endVector = temp;
}
var center = lastPoint - startVector;
lastPoint = center + endVector;
var startAngle = Math.Atan2(startVector.Y, startVector.X);
var endAngle = Math.Atan2(endVector.Y, endVector.X);
if (!a.IsCounterClockwise)
{
var temp = startAngle;
startAngle = endAngle;
endAngle = temp;
}
while (endAngle <= startAngle)
{
endAngle += Math.PI * 2.0;
}
return(new ShxArc(center, a.Radius, startAngle, endAngle));
}
public static ShxArc FromArcCommand(ShxGlyphCommandFractionalArc a, ref ShxPoint lastPoint)
{
var radius = a.HighRadius * 256.0 + a.Radius;
var startOctantAngle = a.StartingOctant * 45.0;
var endOctantAngle = (a.StartingOctant + a.OctantCount - 1) * 45.0;
var startAngleDegrees = (45.0 * a.StartOffset / 256.0) + startOctantAngle;
var startAngleRadians = startAngleDegrees * Math.PI / 180.0;
var endAngleDegrees = (45.0 * a.EndOffset / 256.0) + endOctantAngle;
var endAngleRadians = endAngleDegrees * Math.PI / 180.0;
var startVector = ShxPoint.FromAngleRadians(startAngleRadians) * radius;
var endVector = ShxPoint.FromAngleRadians(endAngleRadians) * radius;
var center = lastPoint - startVector;
lastPoint = center + endVector;
var arc = new ShxArc(center, radius, startAngleRadians, endAngleRadians);
return(arc);
}
