Line
constructor
g.Line(p1, p2)
Return a new line object with start at point p1 and end at point p2. p1 and p2 are first passed through the Point constructor so they can also be passed in string form. Examples:
var l = new g.Line(new g.Point(10, 20), new g.Point(50, 60));
var l = new g.Line('10 20', '50 60');
var l = new g.Line('10@20', '50@60');
The constructor also accepts a single Line object as an argument; it creates a new line with points cloned from the provided line.
Methods
angle()
line.angle()
Return the angle of incline of the line.
The function returns NaN if the two endpoints of the line both lie at the same coordinates (it is impossible to determine the angle of incline of a line that appears to be a point). The line.isDifferentiable() function may be used in advance to determine whether the angle of incline can be computed for a given line.
bbox()
line.bbox()
Return a rectangle that is the bounding box of the line.
bearing()
line.bearing()
Return the bearing (cardinal direction) of the line. The return value is one of the following strings: 'NE', 'E', 'SE', 'S', 'SW', 'W', 'NW' and 'N'.
The function returns 'N' if the two endpoints of the line are coincident.
clone()
line.clone()
Return another line which is a clone of the line.
closestPoint()
line.closestPoint(point)
Return the point on the line that lies closest to point.
closestPointLength()
line.closestPointLength(point)
Return the length of the line up to the point that lies closest to point.
closestPointNormalizedLength()
line.closestPointNormalizedLength(point)
Return the normalized length (distance from the start of the line / total line length) of the line up to the point that lies closest to point.
closestPointTangent()
line.closestPointTangent(point)
Return a line that is tangent to the line at the point that lies closest to point.
The tangent line starts at the identified closest point. The direction from start to end is the same as the direction of the line at the closest point.
If the two endpoints of the line both lie at the same coordinates, null is returned (it is impossible to determine the slope of a point). The line.isDifferentiable() function may be used in advance to determine whether tangents can exist for a given line.
containsPoint()
line.containsPoint(p)
Return true if the point p lies on the line. Return false otherwise.
divideAt()
line.divideAt(t)
Divide the line into two lines at the point that lies t (normalized length) away from the beginning of the line.
Returns an array with two new lines without modifying the original line. For example, if t equals 0.5, the function returns an array of two lines that subdivide the original line at its midpoint.
The function expects t to lie between 0 and 1; values outside the range are constrained to 0 and 1, respectively.
divideAtLength()
line.divideAtLength(length)
Divide the line into two lines at the point that lies length away from the beginning of the line.
Returns an array with two new lines without modifying the original line. If negative length is provided, the algorithm starts looking from the end of the curve. If length is higher than line length, the line is divided at the closest line endpoint instead.
equals()
line.equals(otherLine)
Return true if the line equals the other line.
intersect()
line.intersect(shape)
Return an array of the intersection points of the line with another geometry shape.
A single intersection point is returned, when the shape is a line.
Return null if no intersections are found.
intersection()
line.intersection(l)
Deprecated. Use the line.intersect() function instead.
Return the intersection point of the line with another line l.
A rectangle can also be passed in as the parameter. In that case, an array of intersection points with the line is returned.
Return null if no intersections are found.
intersectionWithLine()
line.intersectionWithLine(line)
Return an array of the intersection points of the line and another line line. Return null if no intersection exists.
isDifferentiable()
line.isDifferentiable()
Return true if a tangent line can be found for the line.
Tangents cannot be found if both of the line endpoints are coincident (the line appears to be a point).
length()
line.length()
Return the length of the line.
midpoint()
line.midpoint()
Return the point that is in the middle of the line.
parallel()
line.parallel(distance)
Return a new line which is parallel with this line. The new line is placed distance from this line in clockwise direction.
var line = new g.Line('0 0', '10 0');
line.parallel(10).toString(); // "0@10 10@10"
line.parallel(-5).toString(); // "0@-5 10@-5"
pointAt()
line.pointAt(t)
Return a point on the line that lies t (normalized length) away from the beginning of the line.
For example, if t equals 0.5, the function returns the midpoint of the line.
The function expects t to lie between 0 and 1; values outside the range are constrained to 0 and 1, respectively.
pointAtLength()
line.pointAtLength(length)
Return a point on the line that lies length away from the beginning of the line.
If negative length is provided, the algorithm starts looking from the end of the line. If length is higher than line length, the closest line endpoint is returned instead.
pointOffset()
line.pointOffset(point)
Return the perpendicular distance between the line and point. The distance is positive if the point lies to the right of the line, negative if the point lies to the left of the line, and 0 if the point lies on the line.
rotate()
line.scale(origin, angle)
Rotate the line by angle around origin.
round()
line.round([precision])
Round all coordinates of the line to the given precision.
Default precision is 0.
Modifies this line in-place, and returns it.
scale()
line.scale(sx, sy [, origin])
Scale the line by sx and sy about the given origin.
If origin is not specified, the line is scaled around 0,0.
serialize()
line.serialize()
Returns the line represented as an SVG points string.
new g.Line('10 10', '20 20').serialize() = "10,10 20,20"
setLength()
line.setLength(length)
Scale the line so that it has the requested length. The start point of the line is preserved.
squaredLength()
line.squaredLength()
Return the squared length of the line.
Useful for distance comparisons in which real length is not necessary (saves one Math.sqrt() operation).
tangentAt()
line.tangentAt(t)
Return a line tangent to the line at point that lies t (normalized length) away from the beginning of the line.
The function expects t to lie between 0 and 1; values outside the range are constrained to 0 and 1, respectively.
The tangent line starts at the specified point. The direction from start to end is the same as the direction of the line.
If the two endpoints of the line both lie at the same coordinates, null is returned (it is impossible to determine the slope of a point). The line.isDifferentiable() function may be used in advance to determine whether tangents can exist for a given line.
tangentAtLength()
line.tangentAtLength(length)
Return a line tangent to the line at point that lies length away from the beginning of the line.
If negative length is provided, the algorithm starts looking from the end of the line. If length is higher than line length, a line tangent to the closest line endpoint is returned instead.
The tangent line starts at the specified point. The direction from start to end is the same as the direction of the line.
If the two endpoints of the line both lie at the same coordinates, null is returned (it is impossible to determine the slope of a point). The line.isDifferentiable() function may be used in advance to determine whether tangents can exist for a given line.
toString()
line.toString()
Returns the line represented as a string.
new g.Line('10 10', '20 20').toString() = "10@10 20@20"
translate()
line.translate(tx [, ty])
Translate the line by tx on the x-axis and by ty on the y-axis.
If only tx is specified and is a number, ty is considered to be zero. If only tx is specified and is an object, it is considered to be a point or an object in the form { x: [number], y: [number] }
vector()
line.vector()
Return the vector (point) of the line with length equal to length of the line.
This function effectively translates the line so that its start lies at 0,0.