private void ensureNoDefault()
{
if (_nonZero.Equals(default(NonZero)))
{
_nonZero = NonZero.One;
}
}
public static Crossings FindCrossings(PathIterator pi,
double xlo, double ylo,
double xhi, double yhi)
{
Crossings cross;
if (pi.GetWindingRule() == PathIterator.WIND_EVEN_ODD)
{
cross = new EvenOdd(xlo, ylo, xhi, yhi);
}
else
{
cross = new NonZero(xlo, ylo, xhi, yhi);
}
// coords array is big enough for holding:
// coordinates returned from currentSegment (6)
// OR
// two subdivided quadratic curves (2+4+4=10)
// AND
// 0-1 horizontal splitting parameters
// OR
// 2 parametric equation derivative coefficients
// OR
// three subdivided cubic curves (2+6+6+6=20)
// AND
// 0-2 horizontal splitting parameters
// OR
// 3 parametric equation derivative coefficients
var coords = new int[23];
double movx = 0;
double movy = 0;
double curx = 0;
double cury = 0;
while (!pi.IsDone())
{
int type = pi.CurrentSegment(coords);
double newx;
double newy;
switch (type)
{
case PathIterator.SEG_MOVETO:
if (movy != cury &&
cross.AccumulateLine(curx, cury, movx, movy))
{
return(null);
}
movx = curx = coords[0];
movy = cury = coords[1];
break;
case PathIterator.SEG_LINETO:
newx = coords[0];
newy = coords[1];
if (cross.AccumulateLine(curx, cury, newx, newy))
{
return(null);
}
curx = newx;
cury = newy;
break;
case PathIterator.SEG_QUADTO:
{
newx = coords[2];
newy = coords[3];
var dblCoords = new double[coords.Length];
for (int i = 0; i < coords.Length; i++)
{
dblCoords[i] = coords[i];
}
if (cross.AccumulateQuad(curx, cury, dblCoords))
{
return(null);
}
curx = newx;
cury = newy;
}
break;
case PathIterator.SEG_CUBICTO:
{
newx = coords[4];
newy = coords[5];
var dblCoords = new double[coords.Length];
for (int i = 0; i < coords.Length; i++)
{
dblCoords[i] = coords[i];
}
if (cross.AccumulateCubic(curx, cury, dblCoords))
{
return(null);
}
curx = newx;
cury = newy;
break;
}
case PathIterator.SEG_CLOSE:
if (movy != cury &&
cross.AccumulateLine(curx, cury, movx, movy))
{
return(null);
}
curx = movx;
cury = movy;
break;
}
pi.Next();
}
if (movy != cury)
{
if (cross.AccumulateLine(curx, cury, movx, movy))
{
return(null);
}
}
return(cross);
}
public NonZero(NonZero nz)
{
this.i = nz.i; this.Mij = nz.Mij;
}
public WithNullable(decimal number, NonZero nonZero)
: this()
{
Number = number;
NonZero = nonZero;
}
public WithEnsure(decimal number, NonZero nonZero)
: this()
{
Number = number;
NonZero = nonZero;
}
public static Crossings FindCrossings(PathIterator pi,
double xlo, double ylo,
double xhi, double yhi)
{
Crossings cross;
if (pi.GetWindingRule() == PathIterator.WIND_EVEN_ODD)
{
cross = new EvenOdd(xlo, ylo, xhi, yhi);
}
else
{
cross = new NonZero(xlo, ylo, xhi, yhi);
}
// coords array is big enough for holding:
// coordinates returned from currentSegment (6)
// OR
// two subdivided quadratic curves (2+4+4=10)
// AND
// 0-1 horizontal splitting parameters
// OR
// 2 parametric equation derivative coefficients
// OR
// three subdivided cubic curves (2+6+6+6=20)
// AND
// 0-2 horizontal splitting parameters
// OR
// 3 parametric equation derivative coefficients
var coords = new int[23];
double movx = 0;
double movy = 0;
double curx = 0;
double cury = 0;
while (!pi.IsDone())
{
int type = pi.CurrentSegment(coords);
double newx;
double newy;
switch (type)
{
case PathIterator.SEG_MOVETO:
if (movy != cury &&
cross.AccumulateLine(curx, cury, movx, movy))
{
return null;
}
movx = curx = coords[0];
movy = cury = coords[1];
break;
case PathIterator.SEG_LINETO:
newx = coords[0];
newy = coords[1];
if (cross.AccumulateLine(curx, cury, newx, newy))
{
return null;
}
curx = newx;
cury = newy;
break;
case PathIterator.SEG_QUADTO:
{
newx = coords[2];
newy = coords[3];
var dblCoords = new double[coords.Length];
for (int i = 0; i < coords.Length; i++)
{
dblCoords[i] = coords[i];
}
if (cross.AccumulateQuad(curx, cury, dblCoords))
{
return null;
}
curx = newx;
cury = newy;
}
break;
case PathIterator.SEG_CUBICTO:
{
newx = coords[4];
newy = coords[5];
var dblCoords = new double[coords.Length];
for (int i = 0; i < coords.Length; i++)
{
dblCoords[i] = coords[i];
}
if (cross.AccumulateCubic(curx, cury, dblCoords))
{
return null;
}
curx = newx;
cury = newy;
break;
}
case PathIterator.SEG_CLOSE:
if (movy != cury &&
cross.AccumulateLine(curx, cury, movx, movy))
{
return null;
}
curx = movx;
cury = movy;
break;
}
pi.Next();
}
if (movy != cury)
{
if (cross.AccumulateLine(curx, cury, movx, movy))
{
return null;
}
}
return cross;
}
Test_NonZero()
{
RType t = new NonZero();
RType u = new NonZero();
Print( ".Equals() and GetHashCode()" );
Assert( t.Equals( t ) );
Assert( t.Equals( u ) );
Assert( t.GetHashCode() == u.GetHashCode() );
Print( "Null passes" );
NonZero.Check( null );
Print( "Negative passes" );
NonZero.Check( Real.Create( -5m ) );
Print( "Positive passes" );
NonZero.Check( Real.Create( 5m ) );
Print( "Zero fails" );
Expect(
e => RTypeException.Match( e,
(vr,f) => vr.Equals( f.Down().Parameter( "item" ) ),
rt => rt.Equals( new NonZero() ) ),
() => NonZero.Check( Real.Create( 0m ) ) );
Print( "CheckParameter()" );
Expect(
e => RTypeException.Match( e,
(vr,f) => vr.Equals( f.Parameter( "param" ) ),
rt => rt.Equals( new NonZero() ) ),
() => NonZero.CheckParameter( Real.Create( 0m ), "param" ) );
}
