org.openimaj.math.geometry.shape

Interface Shape

All Superinterfaces:

Cloneable, GeometricObject2d

All Known Implementing Classes:

Circle, Contour, Ellipse, HoughCircles.WeightedCircle, Polygon, Rectangle, Rectangle3D, RotatedRectangle, Triangle, TriangulatedPolygon

public interface Shape
extends GeometricObject2d, Cloneable

Interface for classes that represent a shape.

Author:

Jonathon Hare (jsh2@ecs.soton.ac.uk)

Method Summary

Modifier and Type	Method and Description
Polygon	asPolygon() Convert the shape to a polygon representation
double	calculateArea() Calculate the area of the shape
double	calculatePerimeter() Calculate the perimeter of the shape
Shape	clone()
double	intersectionArea(Shape that) Calls Polygon.intersectionArea(Shape, int) with 1 step per pixel dimension.
double	intersectionArea(Shape that, int nStepsPerDimension) Return an estimate for the area of the intersection of this polygon and another polygon.
boolean	isConvex() Test if the shape is convex.
boolean	isInside(Point2d point) Test whether the point p is inside the shape.
RotatedRectangle	minimumBoundingRectangle() Compute the minimum size rotated bounding rectangle that contains this shape.
Shape	transform(Jama.Matrix transform) Apply a 3x3 transform matrix to a copy of the GeometricObject2d and return it

Methods inherited from interface org.openimaj.math.geometry.GeometricObject2d

calculateCentroid, calculateRegularBoundingBox, getHeight, getWidth, maxX, maxY, minX, minY, scale, scale, scaleCentroid, translate

Method Detail

isInside

boolean isInside(Point2d point)

Test whether the point p is inside the shape.

Parameters:

point - the point

Returns:

true if the point is inside; false otherwise

calculateArea

double calculateArea()

Calculate the area of the shape

Returns:

the area of the shape

calculatePerimeter

double calculatePerimeter()

Calculate the perimeter of the shape

Returns:

the perimeter of the shape

asPolygon

Polygon asPolygon()

Convert the shape to a polygon representation

Returns:

a polygon representation of the shape

intersectionArea

double intersectionArea(Shape that)

Calls Polygon.intersectionArea(Shape, int) with 1 step per pixel dimension. Subsequently this function returns the shared whole pixels of this polygon and that.

Parameters:

that -

Returns:

intersection area

intersectionArea

double intersectionArea(Shape that,
                        int nStepsPerDimension)

Return an estimate for the area of the intersection of this polygon and another polygon. For each pixel step 1 is added if the point is inside both polygons. The length of a step in each direction is calculated as follows: max(intersectionWidth,intersectionHeight)/ (nStepsPerDimention) The total number of points inside the intersection of the shames is divided by the number of points read and multiplied by the total area of the intersection.

Parameters:

that -

nStepsPerDimension -

Returns:

normalised intersection area

clone

Shape clone()

Returns:

a copy of the shape

minimumBoundingRectangle

RotatedRectangle minimumBoundingRectangle()

Compute the minimum size rotated bounding rectangle that contains this shape.

Returns:

the minimum bounding box

isConvex

boolean isConvex()

Test if the shape is convex.

Returns:

true if the shape is convex; false if non-convex

transform

Shape transform(Jama.Matrix transform)

Description copied from interface: GeometricObject2d

Apply a 3x3 transform matrix to a copy of the GeometricObject2d and return it

Specified by:

transform in interface GeometricObject2d

Parameters:

transform - 3x3 transform matrix

Returns:

the transformed shape