TPointArray

TPointArray related methods

TPointArray.Mean

function TPointArray.Mean(): TPoint; constref;

Wraps Simba’s TPAMiddle

TPointArray.MeanEx

function TPointArray.MeanEx(): Vector2; constref;

Middle as a Vector.

TPointArray.Sort

procedure TPointArray.Sort(From:TPoint=[0,0]);

Wraps Simba’s SortTPAFrom

TPointArray.Sorted

function TPointArray.Sorted(From:TPoint=[0,0]): TPointArray;

Wraps Simba’s SortTPAFrom, produces a sorted copy.

TPointArray.SortByX

procedure TPointArray.SortByX(LowToHi:Boolean=True);

Wraps Simba’s SortTPAByX

TPointArray.SortByY

procedure TPointArray.SortByY(LowToHi:Boolean=True);

Wraps Simba’s SortTPAByY

TPointArray.SortByRow

procedure TPointArray.SortByRow(reverse:Boolean=False);

Sorts a given TPointArray TPA row-by-row, starting from the smallest Y coordinate to the largest Y coordinate, and for every row from the smallest X coordinate to the largest X coordinate.

TPointArray.SortByColumn

procedure TPointArray.SortByColumn(reverse:Boolean=False);

much like SortByRow, but the order of the column comes first

TPointArray.SortFromLine

procedure TPointArray.SortFromLine(p,q:TPoint; reverse:Boolean=False);

The name tells the story

TPointArray.Bounds

function TPointArray.Bounds(): TBox; constref;

Wraps Simba’s GetTPABounds

TPointArray.Edges

function TPointArray.Edges(): TPointArray; constref;

Filters all points out of the given TPointArray which aren’t edge-points. Edge-points are points that are on the edge of the TPA, not completely surrounded by other points. Same as Simba’s FindTPAEdges

TPointArray.Cluster

function TPointArray.Cluster(dist:Int32): T2DPointArray; constref;
function TPointArray.Cluster(distX,distY:Int32): T2DPointArray; constref; overload;

Smart wrapper of Simba’s ClusterTPA and ClusterTPAEx (fall backs to SplitTPA when it’s better suited)

TPointArray.Split

function TPointArray.Split(dist:Int32): T2DPointArray; constref;
function TPointArray.Split(distX,distY:Int32): T2DPointArray; constref; overload;

Wraps Simba’s SplitTPA and SplitTPAEx

TPointArray.ToATPA

function TPointArray.ToATPA(WH:Int32): T2DPointArray; constref;
function TPointArray.ToATPA(W,H:Int32): T2DPointArray; constref; overload;

Wraps Simba’s TPAToATPA and TPAToATPAEx

TPointArray.Offset

function TPointArray.Offset(off: TPoint): TPointArray;

Wraps Simba’s OffsetTPA

TPointArray.Invert

function TPointArray.Invert(Area:TBox=[0,0,-1,-1]): TPointArray; constref;

Inverts the shape based on the area covered, alternatively the given area. Same as ReturnPointsNotInTPA in Simba.

TPointArray.FilterBox

function TPointArray.FilterDist(MinDist,MaxDist: Double; Mx,My: Int32): TPointArray; constref;

Returns a filtered version of the TPA. Same as Simba’s FilterPointsDist

TPointArray.FilterDuplicates

function TPointArray.FilterDuplicates(): TPointArray;

Returns a copy where all duplicate points are removed.

TPointArray.ClearDuplicates

procedure TPointArray.ClearDuplicates();

Removes all the duplicate points from self.

TPointArray.Rotate

function TPointArray.Rotate(AngleRad, MidX, MidY: Double): TPointArray;

Returns a copy where all points are rotated around MidX, MidY. Same as Simba’s RotatePoints.

TPointArray.SplitRows

function TPointArray.SplitRows(dist:Int32): T2DPointArray; constref;

Splits a TPA Arr into TPAs of each row, it then proceeds to further split the rows in to separate TPAs when the given distance dist is less than the distance between the points Same output as SplitTPAEx(TPA,dist,0), but generally faster.

Note

by slacky

Example:

ATPA := TPA.SplitRows(5);

TPointArray.Connect

function TPointArray.Connect(): TPointArray; constref;

Fills a line between all the points (by their order), can be used to get the edges around a polygon

Note

by slacky

Example:

edges := TPA.ConvexHull().Connect();

TPointArray.ConvexHull

function TPointArray.ConvexHull(): TPointArray; constref;

Computes the convex hull around the given TPA. Imagine placing a rubber band around the points, the points which strech the band are the points returned by this function.

See: http://en.wikipedia.org/wiki/Convex_hull for more information.

Note

by slacky

Example:

Smart.Image.DrawTPA(TPA.ConvexHull());

TPointArray.MinAreaRect

function TPointArray.MinAreaRect(): TRectangle;

Computes the minimum bounding box (defined by area) around the given shape. Four points (which are in order) are always returned.

See: http://en.wikipedia.org/wiki/Minimum_bounding_box for more information.

Note

by slacky

Example:

WriteLn('The four box corners are: ', TPA.MinAreaRect());

TPointArray.MinAreaCircle

function TPointArray.MinAreaCircle(): TCircle;

Computes the minimum bounding circle around the given shape.

See: https://en.wikipedia.org/wiki/Smallest-circle_problem for more information.

Implementation is a mixture of a few implementations I’ve seen.

TPointArray.Density

function TPointArray.Density(): Double; constref;

Returns the TPA’s density (Length(TPA)/(width*height))

ExpandPolygon

function ExpandPolygon(Poly:TPointArray; inc:Int32): TPointArray;

A method for increasing the size of any convex polygon.

Note

by slacky

TPointArray.PointsInRangeOf

function TPointArray.PointsInRangeOf(constref Other: TPointArray; MinDist, MaxDist: Double): TPointArray; constref;

Returns all the points from self that are within range of any point in other. The parameters mindist and maxdist determine what “within range” means.

TPointArray.PointsInRangeOf

function TPointArray.PointsInRangeOf(constref Other: TPointArray; MinDistX, MinDistY, MaxDistX, MaxDistY: Double): TPointArray; constref; overload;

Same as the above but lets you specify X- and Y-wise min & max distance separately.