static public bool IsCrop(this Stroq stroke)
{
if (stroke.Cusps().Length == 3 && stroke.Cusps().Straightness(0, 1) < 0.15 & stroke.Cusps().Straightness(1, 2) < 0.15 &&
Math.Abs(stroke.Cusps().inSeg(1).Direction.UnsignedAngle(stroke.Cusps().outSeg(1).Direction) - Math.PI / 2) < Math.PI / 4)
{
return(true);
}
return(false);
}
static public bool BalancedCrops(this Stroq crop1, Stroq crop2)
{
if (crop2 != null &&
(Math.Sign(crop1.Cusps()[1].curvature) == Math.Sign(crop2.Cusps()[1].curvature) ||
((crop1.Cusps().outSeg(1).Direction.Normal().Dot(crop2.Cusps().inSeg(1).Direction.Normal()) < -0.5) &&
(crop1.Cusps().inSeg(1).Direction.Normal().Dot(crop2.Cusps().outSeg(1).Direction.Normal()) < -0.5))))
{
return(false);
}
return(true);
}
static bool insertionCaret(Stroq caret)
{
double dist = (caret.Cusps()[1].dist / caret.Cusps().Distance - 0.5);
bool isCaret = caret.Cusps().Length == 3 &&
Math.Abs(caret.Cusps()[1].dist / caret.Cusps().Distance - 0.5) < .1 &&
caret.Cusps().Straightness(0, 1) < 0.15 && caret.Cusps().Straightness(1, 2) < 0.15 &&
caret.Cusps().inSeg(1).Direction.UnsignedAngle(new Vec(0, -1)) < Math.PI / 4 &&
caret.Cusps().inSeg(1).Direction.UnsignedAngle(-caret.Cusps().outSeg(1).Direction) < Math.PI / 4;
return(isCaret);
}
static public bool IsFlick(this Stroq stroke)
{
if (!stroke.Property.Exists(IS_FLICK))
{
bool flick = stroke.Cusps().Length == 2 && stroke.Cusps().Straightness(0, 1) < 0.15 &&
stroke.Cusps().Distance > 20 &&
stroke.Count * 16 < 353 &&
(stroke.Cusps()[1].pt - stroke.Cusps()[0].pt).Normal().Dot(new Vec(1, -1).Normal()) > 0.65;
stroke.Property[IS_FLICK] = flick;
}
return((bool)stroke.Property[IS_FLICK]);
}
static int leftRightHook(Stroq caret)
{
Pt endpt = Pt.Avg(caret[0], caret[-1]);
int dir = (caret.Cusps().Length == 3 &&
Math.Abs(caret.Cusps()[1].dist / caret.Cusps().Distance - 0.5) < .1 &&
caret.Cusps().Straightness(0, 1) < 0.15 && caret.Cusps().Straightness(1, 2) < 0.15 &&
caret.Cusps().inSeg(1).Direction.UnsignedAngle(-caret.Cusps().outSeg(1).Direction) < Math.PI / 8) ?
(caret.Cusps()[1].pt - endpt).UnsignedAngle(new Vec(1, 0)) < Math.PI / 6 ? 1 :
((caret.Cusps()[1].pt - endpt).UnsignedAngle(new Vec(-1, 0)) < Math.PI / 6 ? -1 : 0) : 0;
return(dir);
}
static public bool IsCircle(this Stroq stroke)
{
if (!stroke.Property.Exists(IS_CIRCLE))
{
bool circle = (stroke[0] - stroke[-1]).Length / stroke.GetBounds().MaxDim < .2;
for (int i = 1; i < stroke.Cusps().Length - 1 && circle; i++)
{
if (Math.Abs(stroke.Cusps()[i].curvature) > 0.6)
{
circle = false;
}
if (Math.Sign(stroke.Cusps()[i].curvature) != Math.Sign(stroke.Cusps()[i - 1].curvature))
{
circle = false;
}
}
stroke.Property[IS_CIRCLE] = circle;
}
return((bool)stroke.Property[IS_CIRCLE]);
}
static Dir doubleHitch(Stroq s)
{
if (s.Cusps().Length == 4 && s.Cusps().Straightness() < zStraightnessTolerance)
{
Vec dir = (s[-1] - s[0]).Normal();
double dx = dir.SignedAngle(Vec.Xaxis);
double ndx = dir.SignedAngle(-Vec.Xaxis);
if (dir.X > 0.3)
{
if (dx > .3)
{
return(Dir.NE);
}
else if (dx < -.3)
{
return(Dir.SE);
}
else
{
return(Dir.E);
}
}
else if (dir.X < 0.3)
{
if (ndx < -.3)
{
return(Dir.NW);
}
else if (ndx > .3)
{
return(Dir.SW);
}
else
{
return(Dir.W);
}
}
}
return(Dir.None);
}
static public object Lassoed(this Stroq stroke, LassoTest test)
{
object sel = null;
DictLookup dict = null;
if (!stroke.Property.Exists(LASSO))
{
dict = new DictLookup();
stroke.Property[LASSO] = dict;
}
else
{
dict = (DictLookup)stroke.Property[LASSO];
}
if (dict.ContainsKey(test))
{
sel = dict[test];
}
else
{
double threshold = stroke.GetBounds().MaxDim * .2;
Stroq lasso = stroke;
// truncate the lasso where it retraces closest to its starting point.
for (int i = stroke.Count - 1; i > Math.Max(stroke.Count / 2, stroke.Cusps()[-2].index); i--)
{
if ((stroke[i] - stroke[0]).Length < threshold)
{
List <Pt> lassoPts = new List <Pt>();
for (int j = 0; j < i; j++)
{
lassoPts.Add(stroke[j]);
}
lasso = new Stroq(lassoPts.ToArray());
}
}
sel = test(lasso);
dict.Add(test, sel);
}
return(sel);
}
static bool isCircular(Pt[] clippepts)
{
Stroq tempStroke = new Stroq(clippepts);
Cusps set = tempStroke.Cusps();
if (set.SelfIntersects.Count > 4)
{
return(false);
}
if (set.Distance > 1.25 * (tempStroke.GetBounds().Width *2 + tempStroke.GetBounds().Height *2))
{
return(false);
}
for (int i = 1; i < set.Length; i++)
{
if (Math.Abs(set[i].curvature) > .75)
{
return(false);
}
}
double d = (tempStroke[-1] - tempStroke[0]).Length / tempStroke.GetBounds().MaxDim;
return(d < 0.75);
}
static public bool IsLasso(this Stroq stroke)
{
double threshold = stroke.GetBounds().MaxDim * .2;
bool canBeLasso = false;
for (int i = stroke.Count - 1; !canBeLasso && i > Math.Max(stroke.Count / 2, stroke.Cusps()[-2].index); i--)
{
if ((stroke[i] - stroke[0]).Length < threshold)
{
canBeLasso = true; // the lasso has returned close enough to the starting point to make it a lasso
}
}
return(canBeLasso);
}
