public void ProcessArc(ShxGlyphCommandOctantArc a)
{
var arc = FromArcCommand(a, ref _lastPoint);
if (_isDrawing)
{
Paths.Add(arc);
}
}
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));
}
