Class mxCurve

java.lang.Object
com.mxgraph.util.mxCurve

public class mxCurve extends Object
  • Field Details

    • points

      protected Map<String,mxPoint[]> points
      A collection of arrays of curve points
    • minXBounds

      protected double minXBounds
    • maxXBounds

      protected double maxXBounds
    • minYBounds

      protected double minYBounds
    • maxYBounds

      protected double maxYBounds
    • intervals

      protected Map<String,double[]> intervals
      An array of arrays of intervals. These intervals define the distance along the edge (0 to 1) that each point lies
    • curveLengths

      protected Map<String,Double> curveLengths
      The curve lengths of the curves
    • CORE_CURVE

      public static String CORE_CURVE
      Defines the key for the central curve index
    • LABEL_CURVE

      public static String LABEL_CURVE
      Defines the key for the label curve index
    • INVALID_POSITION

      public static mxLine INVALID_POSITION
      Indicates that an invalid position on a curve was requested
    • labelBuffer

      protected double labelBuffer
      Offset of the label curve from the curve the label curve is based on. If you wish to set this value, do so directly after creation of the curve. The first time the curve is used the label curve will be created with whatever value is contained in this variable. Changes to it after that point will have no effect.
    • guidePoints

      public List<mxPoint> guidePoints
      The points this curve is drawn through. These are typically control points and are at distances from each other that straight lines between them do not describe a smooth curve. This class takes these guiding points and creates a finer set of internal points that visually appears to be a curve when linked by straight lines
    • valid

      protected boolean valid
      Whether or not the curve currently holds valid values
  • Constructor Details

    • mxCurve

      public mxCurve()
    • mxCurve

      public mxCurve(List<mxPoint> points)
  • Method Details

    • setLabelBuffer

      public void setLabelBuffer(double buffer)
    • getBounds

      public mxRectangle getBounds()
    • getLowerIndexOfSegment

      protected int getLowerIndexOfSegment(String index, double distance)
      Calculates the index of the lower point on the segment that contains the point distance along the
    • getCurveParallel

      public mxLine getCurveParallel(String index, double distance)
      Returns a unit vector parallel to the curve at the specified distance along the curve. To obtain the angle the vector makes with (1,0) perform Math.atan(segVectorY/segVectorX).
      Parameters:
      index - the curve index specifying the curve to analyse
      distance - the distance from start to end of curve (0.0...1.0)
      Returns:
      a unit vector at the specified point on the curve represented as a line, parallel with the curve. If the distance or curve is invalid, mxCurve.INVALID_POSITION is returned
    • getCurveSection

      public mxPoint[] getCurveSection(String index, double start, double end)
      Returns a section of the curve as an array of points
      Parameters:
      index - the curve index specifying the curve to analyse
      start - the start position of the curve segment (0.0...1.0)
      end - the end position of the curve segment (0.0...1.0)
      Returns:
      a sequence of point representing the curve section or null if it cannot be calculated
    • intersectsRect

      public boolean intersectsRect(Rectangle rect)
      Returns whether or not the rectangle passed in hits any part of this curve.
      Parameters:
      rect - the rectangle to detect for a hit
      Returns:
      whether or not the rectangle hits this curve
    • intersectsRectPerimeter

      public mxPoint intersectsRectPerimeter(String index, mxRectangle rect)
      Returns the point at which this curve intersects the boundary of the given rectangle, if it does so. If it does not intersect, null is returned. If it intersects multiple times, the first intersection from the start end of the curve is returned.
      Parameters:
      index - the curve index specifying the curve to analyse
      rect - the whose boundary is to be tested for intersection with this curve
      Returns:
      the point at which this curve intersects the boundary of the given rectangle, if it does so. If it does not intersect, null is returned.
    • intersectsRectPerimeterDist

      public double intersectsRectPerimeterDist(String index, mxRectangle rect)
      Returns the distance from the start of the curve at which this curve intersects the boundary of the given rectangle, if it does so. If it does not intersect, -1 is returned. If it intersects multiple times, the first intersection from the start end of the curve is returned.
      Parameters:
      index - the curve index specifying the curve to analyse
      rect - the whose boundary is to be tested for intersection with this curve
      Returns:
      the distance along the curve from the start at which the intersection occurs
    • collisionMove

      public mxPoint collisionMove(String index, mxRectangle rect, double buffer)
      Returns a point to move the input rectangle to, in order to attempt to place the rectangle away from the curve. NOTE: Curves are scaled, the input rectangle should be also.
      Parameters:
      index - the curve index specifying the curve to analyse
      rect - the rectangle that is to be moved
      buffer - the amount by which the rectangle is to be moved, beyond the dimensions of the rect
      Returns:
      the point to move the top left of the input rect to , otherwise null if no point can be determined
    • intersectRectPerimeterSeg

      protected int intersectRectPerimeterSeg(String index, mxRectangle rect)
      Utility method to determine within which segment the specified rectangle intersects the specified curve
      Parameters:
      index - the curve index specifying the curve to analyse
      rect - the whose boundary is to be tested for intersection with this curve
      Returns:
      the point at which this curve intersects the boundary of the given rectangle, if it does so. If it does not intersect, -1 is returned
    • intersectRectPerimeterSeg

      protected int intersectRectPerimeterSeg(String index, mxRectangle rect, int startSegment)
      Utility method to determine within which segment the specified rectangle intersects the specified curve. This method specifies which segment to start searching at.
      Parameters:
      index - the curve index specifying the curve to analyse
      rect - the whose boundary is to be tested for intersection with this curve
      startSegment - the segment to start searching at. To start at the beginning of the curve, use 1, not 0.
      Returns:
      the point at which this curve intersects the boundary of the given rectangle, if it does so. If it does not intersect, -1 is returned
    • intersectRectPerimeterPoint

      protected mxPoint intersectRectPerimeterPoint(String curveIndex, mxRectangle rect, int indexSeg)
      Returns the point at which this curve segment intersects the boundary of the given rectangle, if it does so. If it does not intersect, null is returned.
      Parameters:
      curveIndex - the curve index specifying the curve to analyse
      rect - the whose boundary is to be tested for intersection with this curve
      indexSeg - the segments on this curve being checked
      Returns:
      the point at which this curve segment intersects the boundary of the given rectangle, if it does so. If it does not intersect, null is returned.
    • getRelativeFromAbsPoint

      public mxRectangle getRelativeFromAbsPoint(mxPoint absPoint, String index)
      Calculates the position of an absolute in terms relative to this curve.
      Parameters:
      absPoint - the point whose relative point is to calculated
      index - the index of the curve whom the relative position is to be calculated from
      Returns:
      an mxRectangle where the x is the distance along the curve (0 to 1), y is the orthogonal offset from the closest segment on the curve and (width, height) is an additional Cartesian offset applied after the other calculations
    • createCoreCurve

      protected void createCoreCurve()
      Creates the core curve that is based on the guide points passed into this class instance
    • isLabelReversed

      public boolean isLabelReversed()
      Whether or not the label curve starts from the end target and traces to the start of the branch
      Returns:
      whether the label curve is reversed
    • createLabelCurve

      protected void createLabelCurve()
    • getBaseLabelCurve

      protected mxPoint[] getBaseLabelCurve()
      Returns the curve the label curve is too be based on
    • populateIntervals

      protected void populateIntervals(String index)
    • updateCurve

      public void updateCurve(List<mxPoint> newPoints)
      Updates the existing curve using the points passed in.
      Parameters:
      newPoints - the new guide points
    • getCurvePoints

      public mxPoint[] getCurvePoints(String index)
      Obtains the points that make up the curve for the specified curve index. If that curve, or the core curve that other curves are based on have not yet been created, then they are lazily created. If creation is impossible, null is returned
      Parameters:
      index - the key specifying the curve
      Returns:
      the points making up that curve, or null
    • getIntervals

      public double[] getIntervals(String index)
    • getCurveLength

      public double getCurveLength(String index)
    • validateCurve

      protected boolean validateCurve()
      Method must be called before any attempt to access curve information
      Returns:
      whether or not the curve may be used
    • updateBounds

      protected void updateBounds(double pointX, double pointY)
      Updates the total bounds of this curve, increasing any dimensions, if necessary, to fit in the specified point
    • getGuidePoints

      public List<mxPoint> getGuidePoints()
      Returns:
      the guidePoints