On-line Guides
All Guides
eBook Store
iOS / Android
Linux for Beginners
Office Productivity
Linux Installation
Linux Security
Linux Utilities
Linux Virtualization
Linux Kernel
Programming
Scripting Languages
Development Tools
Web Development
GUI Toolkits/Desktop
Databases
Mail Systems
openSolaris
Eclipse Documentation
Techotopia.com
Virtuatopia.com

How To Guides
Virtualization
Linux Security
Linux Filesystems
Web Servers
Graphics & Desktop
PC Hardware
Windows
Problem Solutions

Runtime

org.eclipse.gmf.runtime.draw2d.ui.geometry Class PointListUtilities

```java.lang.Object

org.eclipse.gmf.runtime.draw2d.ui.geometry.PointListUtilities
```

```public class PointListUtilities
extends java.lang.Object```

A set of utility methods around manipulating PointList objects

Field Summary
`static int` ``` DEFAULT_BEZIERLINES ```
Constant that is the default number of lines that a bezier is approximated by as a polyline point list.
`static int` ``` DEFAULT_CORNER_APPROXIMATION_PTS ```

Constructor Summary
``` PointListUtilities ()```

Method Summary
```static  PointList ``` ``` calcRoundedCornersPolyline ( PointList points, int r, java.util.Hashtable<java.lang.Integer,java.lang.Integer> rForBendpoint, boolean calculateAppoxPoints)```
Replaces bendpoints (all points except the first and last) in points list by points defining corresponding arcs.
```static  PointList ``` ``` calcSmoothPolyline ( PointList points, int nSmoothFactor, int nBezierSteps)```
Method calcSmoothPolyline.
```static  PointList ``` ``` calcSmoothPolyline ( PointList points, int nSmoothFactor, int nBezierSteps, int nStartIndex, int nEndIndex)```
Calculates the smooth polyline equivalent of the given points list.
```static  Point ``` ``` calculatePointRelativeToLine ( PointList pointList, int fromLine, int fromEnd, boolean isPercentage)```
Finds a point relative to the pointList passed in based on the parameters passed in.
`static boolean` ``` containsPoint ( PointList points, Point point)```
Utility method used to check if a point is contained inside a polygon
```static  PointList ``` ``` copyPoints ( PointList pointsFrom)```
copyPoints This method is necessary because of an apparrent defect in the getCopy() routine of PointList class.
```static  PointList ``` ``` createPointsFromRect ( Rectangle rBox)```
createPointsFromRect
`protected static double` ``` distanceAlong (java.util.List mySegments, Point aPoint)```
Method distanceAlong.
`static boolean` ``` findIntersections ( PointList points, PointList poly, PointList intersections, PointList distances)```
Method findIntersections.
`static int` ``` findNearestLineSegIndexOfPoint ( PointList points, Point ptCoord)```
Method findNearestLineSegIndexOfPoint.
`static java.util.List` ``` getLineSegments ( PointList points)```
Method getLineSegments.
```static  LineSeg ``` ``` getNearestSegment (java.util.List mySegments, int xCoord, int yCoord)```
Static utility method to get the nearest segment in the polyline from the given coordinates.
```static  Point ``` ``` getPointsInfimum ( PointList points)```
Method getPointsSupremum.
`static long` ``` getPointsLength ( PointList points)```
Method getPointsLength.
```static  Point ``` ``` getPointsSupremum ( PointList points)```
Method getPointsSupremum.
`protected static long` ``` length (java.util.List mySegments)```
Method length.
`static boolean` ``` normalizeSegments ( PointList points)```
Normalizes the line segments in the polyline.
`static boolean` ``` normalizeSegments ( PointList points, int straightLineTolerance)```
Normalizes the line segments in the polyline.
```static  Point ``` ``` pickClosestPoint ( PointList points, Point p)```
Assumption: Points in the `PointList` and `Point` p lie on the same line.
```static  Point ``` ``` pickFarestPoint ( PointList points, Point p)```
Assumption: Points in the `PointList` and `Point` p lie on the same line.
```protected static  Point ``` ``` pointOn (java.util.List mySegments, long theDistance, LineSeg.KeyPoint fromKeyPoint, Point ptResult)```
Method pointOn.
```static  Point ``` ``` pointOn ( PointList points, long theDistance, LineSeg.KeyPoint fromKeyPoint, Point ptResult)```
Calculate the point on the polyline given a distance from a key point.
```static  PointList ``` ``` routeAroundPoint ( PointList points, Point ptCenter, int nHeight, int nWidth, int nSmoothFactor, int nInclineOffset, boolean bTop)```
Method routeAroundPoint.
```static  PointList ``` ``` routeAroundPoly ( PointList points, PointList poly, int nSmoothFactor, boolean bShortestDistance, boolean bIncludeIntersectionPoints, int nBuffer)```
Routes this polyline around another polyline that is presumably intersecting with it.
```static  PointList ``` ``` routeAroundRect ( PointList points, Rectangle rBox, int nSmoothFactor, boolean bIncludeIntersectionPoints, int nBuffer)```
Method routeAroundRect.
`protected static double` ``` segmentDistance (java.util.List mySegments, LineSeg theSegment, LineSeg.KeyPoint uptoKeyPoint)```
Method segmentDistance.

Methods inherited from class java.lang.Object
`clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait`

Field Detail

DEFAULT_BEZIERLINES

```public static final int DEFAULT_BEZIERLINES
```
Constant that is the default number of lines that a bezier is approximated by as a polyline point list.

Constant Field Values

DEFAULT_CORNER_APPROXIMATION_PTS

```public static final int DEFAULT_CORNER_APPROXIMATION_PTS
```
Since:
1.2
Constant Field Values
Constructor Detail

PointListUtilities

`public PointListUtilities()`
Method Detail

normalizeSegments

```public static boolean normalizeSegments(
PointList points)```
Normalizes the line segments in the polyline. Checks for lines that are with-in a threshold for length and removes them. Additionally, it will remove points that that adjacent segments that are both horizontal, or both vertical.

Parameters:
`points` - `PointList` to be normalized
Returns:
`boolean` `true` if segments were changed, `false` otherwise

normalizeSegments

```public static boolean normalizeSegments(
PointList points,
int straightLineTolerance)```
Normalizes the line segments in the polyline. Checks for lines that are with-in a threshold for length and removes them. Additionally, it will remove points that that adjacent segments that are both horizontal, or both vertical. Will utilize a tolerance value to determine if segments needs to flattened or not.

Parameters:
`points` - `PointList` to normalize
`straightLineTolerance` - the tolerance value within which indicates the line is straight in relative coordinates.
Returns:
`boolean` `true` if segments were changed, `false` otherwise

getPointsSupremum

```public static
Point getPointsSupremum(
PointList points)```
Method getPointsSupremum. Get points representing the extrema for this poly line.

Parameters:
`points` - PointList to calculate the highest point from.
Returns:
Point value of the highest point in the bounding box of the polyline.

getPointsInfimum

```public static
Point getPointsInfimum(
PointList points)```
Method getPointsSupremum. Get points representing the minimum for this poly line.

Parameters:
`points` - PointList to calculate the minimum point from.
Returns:
Point value of the lowest point in the bounding box of the polyline.

createPointsFromRect

```public static
PointList createPointsFromRect(
Rectangle rBox)```
createPointsFromRect

Parameters:
`rBox` - Rectangle to base the PointList from
Returns:
PointList that is equivalent to the Rectangle

routeAroundRect

```public static
PointList routeAroundRect(
PointList points,

Rectangle rBox,
int nSmoothFactor,
boolean bIncludeIntersectionPoints,
int nBuffer)```
Method routeAroundRect. Route this polyline around a rectangle that is presumably intersecting with it.

Parameters:
`points` - PointList that will be modified to route around the given rectangle
`rBox` - the `Rectangle` around which the routing will occur.
`nSmoothFactor` - the `int` smooth factor to route the line with 0 - None, 15 - some, 30 - lots
`bIncludeIntersectionPoints` - the `boolean` determining whether to include the points that intersect with the rectangle in the newly routed polyline.
`nBuffer` - the `int` buffer around the rectangle.
Returns:
`PointList` that is the newly routed version of `points` of `null` if operation was not successful or if the calculation is not possible.

getLineSegments

```public static java.util.List getLineSegments(
PointList points)```
Method getLineSegments. Converts the points of this polyline into a list of `LineSeg` objects

Parameters:
`points` - PointList to get LineSeg equivalents of.
Returns:
List of LineSeg objects.

routeAroundPoly

```public static
PointList routeAroundPoly(
PointList points,

PointList poly,
int nSmoothFactor,
boolean bShortestDistance,
boolean bIncludeIntersectionPoints,
int nBuffer)```
Routes this polyline around another polyline that is presumably intersecting with it.

Parameters:
`points` - the `PointList` that is to be modified based on the routing calculations made around the `poly` parameter.
`poly` - the `PolylinePointList` around which the routing will occur.
`nSmoothFactor` - the `int` smooth factor to route the line with 0 - None, 15 - some, 30 - lots
`bShortestDistance` - the `boolean` determining whether to use the shortest distance possible to achieve this or else minimally modify the existing polyline.
`bIncludeIntersectionPoints` - the `boolean` determining whether to include the points that intersect with the rectangle in the newly routed polyline.
`nBuffer` - the `int` buffer around the rectangle.
Returns:
`PointList` that is the newly routed version of `points` of `null` if operation was not successful or if the calculation is not possible.

copyPoints

```public static
PointList copyPoints(
PointList pointsFrom)```
copyPoints This method is necessary because of an apparrent defect in the getCopy() routine of PointList class. It is initializing the copy based on size but then making the copy based on the array allocation which may be different causing an ArrayIndexOutOfBounds exception.

Parameters:
`pointsFrom` -
Returns:
PointList

calcSmoothPolyline

```public static final
PointList calcSmoothPolyline(
PointList points,
int nSmoothFactor,
int nBezierSteps)```
Method calcSmoothPolyline. Calculate the smooth polyline approximation of this polyline based on a smooth factor.

Parameters:
`points` - the `PointList` that is used to calculate the smooth point list from.
`nSmoothFactor` - the `int` smooth factor to smooth the line with 0 - None, 15 - some, 30 - lots
`nBezierSteps` - the `int` number of line steps used to approximate the smooth curve
Returns:
PolylinePointList List of PolylinePoint representing the smooth polyline.

calcSmoothPolyline

```public static
PointList calcSmoothPolyline(
PointList points,
int nSmoothFactor,
int nBezierSteps,
int nStartIndex,
int nEndIndex)```
Calculates the smooth polyline equivalent of the given points list. It will extrapolate a bezier approximation in polylines that resembles a curved line.

Parameters:
`points` - the `PointList` that is used to calculate the smooth bezier approximation.
`nSmoothFactor` - the `int` smooth factor to smooth the line with 0 - None, 15 - some, 30 - lots
`nBezierSteps` - the `int` number of line steps used to approximate the smooth curve
`nStartIndex` - the `int` index in the line to start from to create the smooth approximation
`nEndIndex` - the `int` index in the line to end at to create the smooth approximation
Returns:
PolylinePointList List of PolylinePoint representing the smooth polyline.

pointOn

```public static
Point pointOn(
PointList points,
long theDistance,

LineSeg.KeyPoint fromKeyPoint,

Point ptResult)```
Calculate the point on the polyline given a distance from a key point.

Parameters:
`points` - the `PointList` to calculate the point on the polyline.
`theDistance` - the `long` x coordinate of the point
`fromKeyPoint` - the `int` constant value indicating the key point Origin, Terminus, Midpoint
`ptResult` - the `Point` where the resulting point value is set.
Returns:
Point the calculated point residing on the polyline.

getPointsLength

```public static long getPointsLength(
PointList points)```
Method getPointsLength. Static utility function to calculate the length of a series of points if interpreted as line segments.

Parameters:
`points` - PointList to calculate the length of.
Returns:
length of the line segments

length

`protected static long length(java.util.List mySegments)`
Method length. Static utility function to calculate the length of a series of line segments.

Parameters:
`mySegments` - List of line segments to calculate the length of.
Returns:
long length of the line segments

getNearestSegment

```public static
LineSeg getNearestSegment(java.util.List mySegments,
int xCoord,
int yCoord)```
Static utility method to get the nearest segment in the polyline from the given coordinates.

Parameters:
`mySegments` - the `List` of `LineSeg` objects
`xCoord` - the `int` x coordinate of the point
`yCoord` - the `int` y coordinate of the point
Returns:
the `LineSeg` by reference which is closest to the given coordinates.

pointOn

```protected static
Point pointOn(java.util.List mySegments,
long theDistance,

LineSeg.KeyPoint fromKeyPoint,

Point ptResult)```
Method pointOn. Static utility function used by `pointOn`.

Parameters:
`mySegments` -
`theDistance` - the `long` x coordinate of the point
`fromKeyPoint` - the `int` constant value indicating the key point Origin, Terminus, Midpoint
`ptResult` - the `Point` where the resulting point value is set.
Returns:
Point the calculated point residing on the polyline.

distanceAlong

```protected static double distanceAlong(java.util.List mySegments,

Point aPoint)```
Method distanceAlong. Static utility function to calculate the distanceAlong a series of line segments a given point is on the line.

Parameters:
`mySegments` -
`aPoint` - Point to calculate the distance along the polyline of.
Returns:
double value of the distance along the polyline of the given point.

segmentDistance

```protected static double segmentDistance(java.util.List mySegments,

LineSeg theSegment,

LineSeg.KeyPoint uptoKeyPoint)```
Method segmentDistance. Compute the percentage of the distance along this polyline that the given segment occurs. If the keypoint specified is Origin, then the given segment will not be included in the percentage; if the keypoint is Midpoint, then half of the length will be included; if the keypoint is Terminus, the the whole length will be included. The segment must be a segment of this polyline.

Parameters:
`mySegments` -
`theSegment` -
`uptoKeyPoint` -
Returns:
double

routeAroundPoint

```public static
PointList routeAroundPoint(
PointList points,

Point ptCenter,
int nHeight,
int nWidth,
int nSmoothFactor,
int nInclineOffset,
boolean bTop)```
Method routeAroundPoint. Calculate a new routed version of this polyline that will route itself around a given point.

Parameters:
`points` - PointList to modify
`ptCenter` - the `Point` around which the routing will occur.
`nHeight` - the `int` height to route around the point.
`nWidth` - the `int` width to route around the point.
`nSmoothFactor` - the `int` smooth factor to route the line with 0 - None, 15 - some, 30 - lots
`nInclineOffset` - the `int` amount to incline the routed points.
`bTop` - the `boolean` route above or below the point on the line.
Returns:
`PointList` that is the newly routed version of `points` of `null` if operation was not successful or if the calculation is not possible.

findNearestLineSegIndexOfPoint

```public static int findNearestLineSegIndexOfPoint(
PointList points,

Point ptCoord)```
Method findNearestLineSegIndexOfPoint. Calculate the nearest line segment index distance wise to the given point.

Parameters:
`points` - PointList to calculate the nearest line segment of.
`ptCoord` - the `Point` to test containment of.
Returns:
int Index of line segment that is nearest in the polyline to the given point. The index is 1 based where 1 represents the first segment.

findIntersections

```public static boolean findIntersections(
PointList points,

PointList poly,

PointList intersections,

PointList distances)```
Method findIntersections. Find all intersection points between this polyline and another polyline passed into the method.

Parameters:
`points` - PointList to calculate interesections with.
`poly` - the `PointList` to calculate intersections with.
`intersections` - the `PointList` containing the resulting calculated intersection points.
`distances` - the `PointList` containing point values representing the distance along the polyline the intersections occur.
Returns:
boolean true if intersections could be calculated, false otherwise.

calculatePointRelativeToLine

```public static
Point calculatePointRelativeToLine(
PointList pointList,
int fromLine,
int fromEnd,
boolean isPercentage)```
Finds a point relative to the pointList passed in based on the parameters passed in.

Parameters:
`pointList` - the `PointList`
`fromLine` - distance off the line
`fromEnd` - distance from the starting point of the line (i.e. distance from source end along the line)
`isPercentage` - is the fromEnd given as a percentage?
Returns:
Point

pickClosestPoint

```public static
Point pickClosestPoint(
PointList points,

Point p)```
Assumption: Points in the `PointList` and `Point` p lie on the same line. Returns the `Point` from the `PointList` closest to @param p

Parameters:
`points` - - the list of points to select the result from
`p` - - the point to which the closest point must be found
Returns:
the `Point` from the `PointList` closest to @param p

pickFarestPoint

```public static
Point pickFarestPoint(
PointList points,

Point p)```
Assumption: Points in the `PointList` and `Point` p lie on the same line. Returns the `Point` from the `PointList` closest to @param p

Parameters:
`points` - - the list of points to select the result from
`p` - - the point to which the closest point must be found
Returns:
the `Point` from the `PointList` closest to @param p

containsPoint

```public static boolean containsPoint(
PointList points,

Point point)```
Utility method used to check if a point is contained inside a polygon

Parameters:
`points` - the polygon
`point` - point to check
Returns:
true is the pointis inside the polygon, otherwise false

calcRoundedCornersPolyline

```public static
PointList calcRoundedCornersPolyline(
PointList points,
int r,
java.util.Hashtable<java.lang.Integer,java.lang.Integer> rForBendpoint,
boolean calculateAppoxPoints)```
Replaces bendpoints (all points except the first and last) in points list by points defining corresponding arcs. That is, each bendpoint is replaced with the start and end point of the arc, and if calculateApproxPoints is true, there will also be points in between that approximate the arc. Arc size is r. Sometimes, segment between two bendpoints is shorter than r. In that case, arc size for both bendpoints has to be reduced to be half of the segment length, so that both arcs can fit. These reduced arc sizes (if any) are kept in rForBendpoint hashtable.

Parameters:
`points` - Initial list of connection points
`r` - Size (radius) of the arc that should replace bendpoint
`rForBendpoint` - Hashtable keeping track of bendpoints whose arcs have to be smaller than r
`calculateAppoxPoints` - Indicates if arcs replacing bendpoints should be approximated
Returns:
Since:
1.2

Runtime