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Diffstat (limited to 'java/awt/Polygon.java')
-rw-r--r-- | java/awt/Polygon.java | 954 |
1 files changed, 704 insertions, 250 deletions
diff --git a/java/awt/Polygon.java b/java/awt/Polygon.java index 09cbf2b6c..52952700f 100644 --- a/java/awt/Polygon.java +++ b/java/awt/Polygon.java @@ -1,5 +1,5 @@ -/* Polygon.java -- Class representing a polygon - Copyright (C) 1999 Free Software Foundation, Inc. +/* Polygon.java -- class representing a polygon + Copyright (C) 1999, 2002 Free Software Foundation, Inc. This file is part of GNU Classpath. @@ -38,256 +38,710 @@ exception statement from your version. */ package java.awt; -/** - * This class represents a polygon - * - * @author Aaron M. Renn (arenn@urbanophile.com) - */ -public class Polygon implements Shape, java.io.Serializable -{ - -/* - * Instance Variables - */ - -/** - * This total number of endpoints - */ -public int npoints; - -/** - * The array of X coordinates of endpoints. - */ -public int xpoints[]; - -/** - * The array of Y coordinates of endpoints. - */ -public int ypoints[]; +import java.awt.geom.AffineTransform; +import java.awt.geom.PathIterator; +import java.awt.geom.Point2D; +import java.awt.geom.Rectangle2D; +import java.io.Serializable; /** - * The bounding box of this polygon - */ -protected Rectangle bounds; - -/*************************************************************************/ - -/* - * Constructors + * This class represents a polygon, a closed, two-dimensional region in a + * coordinate space. The region is bounded by an arbitrary number of line + * segments, between (x,y) coordinate vertices. The polygon has even-odd + * winding, meaning that a point is inside the shape if it crosses the + * boundary an odd number of times on the way to infinity. + * + * <p>There are some public fields; if you mess with them in an inconsistent + * manner, it is your own fault when you get NullPointerException, + * ArrayIndexOutOfBoundsException, or invalid results. Also, this class is + * not threadsafe. + * + * @author Aaron M. Renn <arenn@urbanophile.com> + * @author Eric Blake <ebb9@email.byu.edu> + * @since 1.0 + * @status updated to 1.4 */ - -/** - * Initializes a new instance of <code>Polygon</code> that is empty. - */ -public -Polygon() -{ - xpoints = new int[0]; - ypoints = new int[0]; - - bounds = new Rectangle(0,0,0,0); -} - -/*************************************************************************/ - -/** - * Initializes a new instance of <code>Polygon</code> that has the - * specified endpoints. - * - * @param xpoints The array of X coordinates for this polygon. - * @param ypoints The array of Y coordinates for this polygon. - * @param npoints The total number of endpoints in this polygon. - * - * @exception NegativeArraySizeException If <code>npoints</code> is negative. - */ -public -Polygon(int[] xpoints, int[] ypoints, int npoints) -{ - if (npoints < 0) - throw new NegativeArraySizeException(); - - this.xpoints = xpoints; - this.ypoints = ypoints; - this.npoints = npoints; - - calculateBounds(); -} - -/*************************************************************************/ - -/* - * Instance Methods - */ - -/** - * Calculates the bounding rectangle of this polygon. - */ -public void -calculateBounds() -{ - int minx = xpoints[0], maxx = xpoints[0]; - int miny = ypoints[0], maxy = ypoints[0]; - - for (int i = 0; i < npoints; i++) - { - if (xpoints[i] < minx) - minx = xpoints[i]; - - if (xpoints[i] > maxx) - maxx = xpoints[i]; - - if (ypoints[i] < miny) - miny = ypoints[i]; - - if (ypoints[i] > maxy) - maxy = ypoints[i]; - } - - bounds = new Rectangle(minx, maxy, maxx-minx, maxy-miny); -} - -/*************************************************************************/ - -/** - * Translates the polygon by adding the specified values to all X and Y - * coordinates. - * - * @param dx The amount to add to all X coordinates. - * @param dy The amount to add to all Y coordinates. - */ -public void -translate(int dx, int dy) +public class Polygon implements Shape, Serializable { - for (int i = 0; i < npoints; i++) + /** + * Compatible with JDK 1.0+. + */ + private static final long serialVersionUID = -6460061437900069969L; + + /** + * This total number of endpoints. + * + * @serial the number of endpoints, possibly less than the array sizes + */ + public int npoints; + + /** + * The array of X coordinates of endpoints. This should not be null. + * + * @see #addPoint(int, int) + * @serial the x coordinates + */ + public int[] xpoints; + + /** + * The array of Y coordinates of endpoints. This should not be null. + * + * @see #addPoint(int, int) + * @serial the y coordinates + */ + public int[] ypoints; + + /** + * The bounding box of this polygon. This is lazily created and cached, so + * it must be invalidated after changing points. + * + * @see #getBounds() + * @serial the bounding box, or null + */ + protected Rectangle bounds; + + /** + * Cached flattened version - condense points and parallel lines, so the + * result has area if there are >= 3 condensed vertices. flat[0] is the + * number of condensed points, and (flat[odd], flat[odd+1]) form the + * condensed points. + * + * @see #condense() + * @see #contains(double, double) + * @see #contains(double, double, double, double) + */ + private transient int[] condensed; + + /** + * Initializes an empty polygon. + */ + public Polygon() + { + // Leave room for growth. + xpoints = new int[4]; + ypoints = new int[4]; + } + + /** + * Create a new polygon with the specified endpoints. + * + * @param xpoints the array of X coordinates for this polygon + * @param ypoints the array of Y coordinates for this polygon + * @param npoints the total number of endpoints in this polygon + * @throws NegativeArraySizeException if npoints is negative + * @throws IndexOutOfBoundsException if npoints exceeds either array + * @throws NullPointerException if xpoints or ypoints is null + */ + public Polygon(int[] xpoints, int[] ypoints, int npoints) + { + if (npoints < 0) + throw new NegativeArraySizeException(); + if (npoints > xpoints.length || npoints > ypoints.length) + throw new IndexOutOfBoundsException(); + this.xpoints = xpoints; + this.ypoints = ypoints; + this.npoints = npoints; + } + + /** + * Reset the polygon to be empty. The arrays are left alone, to avoid object + * allocation, but the number of points is set to 0, and all cached data + * is discarded. If you are discarding a huge number of points, it may be + * more efficient to just create a new Polygon. + * + * @see #invalidate() + * @since 1.4 + */ + public void reset() + { + npoints = 0; + invalidate(); + } + + /** + * Invalidate or flush all cached data. After direct manipulation of the + * public member fields, this is necessary to avoid inconsistent results + * in methods like <code>contains</code>. + * + * @see #getBounds() + * @since 1.4 + */ + public void invalidate() + { + bounds = null; + condensed = null; + } + + /** + * Translates the polygon by adding the specified values to all X and Y + * coordinates. This updates the bounding box, if it has been calculated. + * + * @param dx the amount to add to all X coordinates + * @param dy the amount to add to all Y coordinates + * @since 1.1 + */ + public void translate(int dx, int dy) + { + int i = npoints; + while (--i >= 0) + { + xpoints[i] += dx; + xpoints[i] += dy; + } + if (bounds != null) + { + bounds.x += dx; + bounds.y += dy; + } + condensed = null; + } + + /** + * Adds the specified endpoint to the polygon. This updates the bounding + * box, if it has been created. + * + * @param x the X coordinate of the point to add + * @param y the Y coordiante of the point to add + */ + public void addPoint(int x, int y) + { + if (npoints + 1 > xpoints.length) + { + int[] newx = new int[npoints + 1]; + System.arraycopy(xpoints, 0, newx, 0, npoints); + xpoints = newx; + } + if (npoints + 1 > ypoints.length) + { + int[] newy = new int[npoints + 1]; + System.arraycopy(ypoints, 0, newy, 0, npoints); + ypoints = newy; + } + xpoints[npoints] = x; + ypoints[npoints] = y; + npoints++; + if (bounds != null) + { + if (npoints == 1) + { + bounds.x = x; + bounds.y = y; + } + else + { + if (x < bounds.x) + { + bounds.width += bounds.x - x; + bounds.x = x; + } + else if (x > bounds.x + bounds.width) + bounds.width = x - bounds.x; + if (y < bounds.y) + { + bounds.height += bounds.y - y; + bounds.y = y; + } + else if (y > bounds.y + bounds.height) + bounds.height = y - bounds.y; + } + } + condensed = null; + } + + /** + * Returns the bounding box of this polygon. This is the smallest + * rectangle with sides parallel to the X axis that will contain this + * polygon. + * + * @return the bounding box for this polygon + * @see #getBounds2D() + * @since 1.1 + */ + public Rectangle getBounds() + { + if (bounds == null) + { + if (npoints == 0) + return bounds = new Rectangle(); + int i = npoints - 1; + int minx = xpoints[i]; + int maxx = minx; + int miny = ypoints[i]; + int maxy = miny; + while (--i >= 0) + { + int x = xpoints[i]; + int y = ypoints[i]; + if (x < minx) + minx = x; + else if (x > maxx) + maxx = x; + if (y < miny) + miny = y; + else if (y > maxy) + maxy = y; + } + bounds = new Rectangle(minx, maxy, maxx - minx, maxy - miny); + } + return bounds; + } + + /** + * Returns the bounding box of this polygon. This is the smallest + * rectangle with sides parallel to the X axis that will contain this + * polygon. + * + * @return the bounding box for this polygon + * @see #getBounds2D() + * @deprecated use {@link #getBounds()} instead + */ + public Rectangle getBoundingBox() + { + return getBounds(); + } + + /** + * Tests whether or not the specified point is inside this polygon. + * + * @param p the point to test + * @return true if the point is inside this polygon + * @throws NullPointerException if p is null + * @see #contains(double, double) + */ + public boolean contains(Point p) + { + return contains(p.getX(), p.getY()); + } + + /** + * Tests whether or not the specified point is inside this polygon. + * + * @param x the X coordinate of the point to test + * @param y the Y coordinate of the point to test + * @return true if the point is inside this polygon + * @see #contains(double, double) + * @since 1.1 + */ + public boolean contains(int x, int y) + { + return contains((double) x, (double) y); + } + + /** + * Tests whether or not the specified point is inside this polygon. + * + * @param x the X coordinate of the point to test + * @param y the Y coordinate of the point to test + * @return true if the point is inside this polygon + * @see #contains(double, double) + * @deprecated use {@link #contains(int, int)} instead + */ + public boolean inside(int x, int y) + { + return contains((double) x, (double) y); + } + + /** + * Returns a high-precision bounding box of this polygon. This is the + * smallest rectangle with sides parallel to the X axis that will contain + * this polygon. + * + * @return the bounding box for this polygon + * @see #getBounds() + * @since 1.2 + */ + public Rectangle2D getBounds2D() + { + // For polygons, the integer version is exact! + return getBounds(); + } + + /** + * Tests whether or not the specified point is inside this polygon. + * + * @param x the X coordinate of the point to test + * @param y the Y coordinate of the point to test + * @return true if the point is inside this polygon + * @since 1.2 + */ + public boolean contains(double x, double y) + { + // First, the obvious bounds checks. + if (! condense() || ! getBounds().contains(x, y)) + return false; + // A point is contained if a ray to (-inf, y) crosses an odd number + // of segments. This must obey the semantics of Shape when the point is + // exactly on a segment or vertex. Note that we are guaranteed that the + // condensed polygon has area, and no two segments with identical slope. + int intersections = 0; + int limit = condensed[0]; + int curx = condensed[(limit << 1) - 1]; + int cury = condensed[limit << 1]; + for (int i = 1; i <= limit; i++) + { + int priorx = curx; + int priory = cury; + curx = condensed[(i << 1) - 1]; + cury = condensed[i << 1]; + if ((priorx > x && curx > x) // Left of segment, or NaN. + || (priory > y && cury > y) // Below segment, or NaN. + || (priory < y && cury < y)) // Above segment. + continue; + if (priory == cury) // Horizontal segment, y == cury == priory + { + if (priorx < x && curx < x) // Right of segment. + { + intersections++; + continue; + } + // Did we approach this segment from above or below? + // This mess is necessary to obey rules of Shape. + priory = condensed[((limit + i - 2) % limit) << 1]; + boolean above = priory > cury; + if ((curx == x && (curx > priorx || above)) + || (priorx == x && (curx < priorx || ! above)) + || (curx > priorx && ! above) || above) + intersections++; + continue; + } + if (priorx == x && priory == y) // On prior vertex. + continue; + if (priorx == curx // Vertical segment. + || (priorx < x && curx < x)) // Right of segment. + { + intersections++; + continue; + } + // The point is inside the segment's bounding box, compare slopes. + double slopeseg = (double) (cury - priory) / (curx - priorx); + double slopepoint = (double) (y - priory) / (x - priorx); + if ((slopeseg > 0 && slopeseg > slopepoint) + || slopeseg < slopepoint) + intersections++; + } + return (intersections & 1) != 0; + } + + /** + * Tests whether or not the specified point is inside this polygon. + * + * @param p the point to test + * @return true if the point is inside this polygon + * @throws NullPointerException if p is null + * @see #contains(double, double) + * @since 1.2 + */ + public boolean contains(Point2D p) + { + return contains(p.getX(), p.getY()); + } + + /** + * Test if a high-precision rectangle intersects the shape. This is true + * if any point in the rectangle is in the shape. This implementation is + * precise. + * + * @param x the x coordinate of the rectangle + * @param y the y coordinate of the rectangle + * @param w the width of the rectangle, treated as point if negative + * @param h the height of the rectangle, treated as point if negative + * @return true if the rectangle intersects this shape + * @since 1.2 + */ + public boolean intersects(double x, double y, double w, double h) + { + // First, the obvious bounds checks. + if (w <= 0 || h <= 0 || npoints == 0 || + ! getBounds().intersects(x, y, w, h)) + return false; // Disjoint bounds. + if ((x <= bounds.x && x + w >= bounds.x + bounds.width + && y <= bounds.y && y + h >= bounds.y + bounds.height) + || contains(x, y)) + return true; // Rectangle contains the polygon, or one point matches. + // If any vertex is in the rectangle, the two might intersect. + int curx = 0; + int cury = 0; + for (int i = 0; i < npoints; i++) + { + curx = xpoints[i]; + cury = ypoints[i]; + if (curx >= x && curx < x + w && cury >= y && cury < y + h + && contains(curx, cury)) // Boundary check necessary. + return true; + } + // Finally, if at least one of the four bounding lines intersect any + // segment of the polygon, return true. Be careful of the semantics of + // Shape; coinciding lines do not necessarily return true. + for (int i = 0; i < npoints; i++) + { + int priorx = curx; + int priory = cury; + curx = xpoints[i]; + cury = ypoints[i]; + if (priorx == curx) // Vertical segment. + { + if (curx < x || curx >= x + w) // Outside rectangle. + continue; + if ((cury >= y + h && priory <= y) + || (cury <= y && priory >= y + h)) + return true; // Bisects rectangle. + continue; + } + if (priory == cury) // Horizontal segment. + { + if (cury < y || cury >= y + h) // Outside rectangle. + continue; + if ((curx >= x + w && priorx <= x) + || (curx <= x && priorx >= x + w)) + return true; // Bisects rectangle. + continue; + } + // Slanted segment. + double slope = (double) (cury - priory) / (curx - priorx); + double intersect = slope * (x - curx) + cury; + if (intersect > y && intersect < y + h) // Intersects left edge. + return true; + intersect = slope * (x + w - curx) + cury; + if (intersect > y && intersect < y + h) // Intersects right edge. + return true; + intersect = (y - cury) / slope + curx; + if (intersect > x && intersect < x + w) // Intersects bottom edge. + return true; + intersect = (y + h - cury) / slope + cury; + if (intersect > x && intersect < x + w) // Intersects top edge. + return true; + } + return false; + } + + /** + * Test if a high-precision rectangle intersects the shape. This is true + * if any point in the rectangle is in the shape. This implementation is + * precise. + * + * @param r the rectangle + * @return true if the rectangle intersects this shape + * @throws NullPointerException if r is null + * @see #intersects(double, double, double, double) + * @since 1.2 + */ + public boolean intersects(Rectangle2D r) + { + return intersects(r.getX(), r.getY(), r.getWidth(), r.getHeight()); + } + + /** + * Test if a high-precision rectangle lies completely in the shape. This is + * true if all points in the rectangle are in the shape. This implementation + * is precise. + * + * @param x the x coordinate of the rectangle + * @param y the y coordinate of the rectangle + * @param w the width of the rectangle, treated as point if negative + * @param h the height of the rectangle, treated as point if negative + * @return true if the rectangle is contained in this shape + * @since 1.2 + */ + public boolean contains(double x, double y, double w, double h) + { + // First, the obvious bounds checks. + if (w <= 0 || h <= 0 || ! contains(x, y) + || ! bounds.contains(x, y, w, h)) + return false; + // Now, if any of the four bounding lines intersects a polygon segment, + // return false. The previous check had the side effect of setting + // the condensed array, which we use. Be careful of the semantics of + // Shape; coinciding lines do not necessarily return false. + int limit = condensed[0]; + int curx = condensed[(limit << 1) - 1]; + int cury = condensed[limit << 1]; + for (int i = 1; i <= limit; i++) + { + int priorx = curx; + int priory = cury; + curx = condensed[(i << 1) - 1]; + cury = condensed[i << 1]; + if (curx > x && curx < x + w && cury > y && cury < y + h) + return false; // Vertex is in rectangle. + if (priorx == curx) // Vertical segment. + { + if (curx < x || curx > x + w) // Outside rectangle. + continue; + if ((cury >= y + h && priory <= y) + || (cury <= y && priory >= y + h)) + return false; // Bisects rectangle. + continue; + } + if (priory == cury) // Horizontal segment. + { + if (cury < y || cury > y + h) // Outside rectangle. + continue; + if ((curx >= x + w && priorx <= x) + || (curx <= x && priorx >= x + w)) + return false; // Bisects rectangle. + continue; + } + // Slanted segment. + double slope = (double) (cury - priory) / (curx - priorx); + double intersect = slope * (x - curx) + cury; + if (intersect > y && intersect < y + h) // Intersects left edge. + return false; + intersect = slope * (x + w - curx) + cury; + if (intersect > y && intersect < y + h) // Intersects right edge. + return false; + intersect = (y - cury) / slope + curx; + if (intersect > x && intersect < x + w) // Intersects bottom edge. + return false; + intersect = (y + h - cury) / slope + cury; + if (intersect > x && intersect < x + w) // Intersects top edge. + return false; + } + return true; + } + + /** + * Test if a high-precision rectangle lies completely in the shape. This is + * true if all points in the rectangle are in the shape. This implementation + * is precise. + * + * @param r the rectangle + * @return true if the rectangle is contained in this shape + * @throws NullPointerException if r is null + * @see #contains(double, double, double, double) + * @since 1.2 + */ + public boolean contains(Rectangle2D r) + { + return contains(r.getX(), r.getY(), r.getWidth(), r.getHeight()); + } + + /** + * Return an iterator along the shape boundary. If the optional transform + * is provided, the iterator is transformed accordingly. Each call returns + * a new object, independent from others in use. This class is not + * threadsafe to begin with, so the path iterator is not either. + * + * @param transform an optional transform to apply to the iterator + * @return a new iterator over the boundary + * @since 1.2 + */ + public PathIterator getPathIterator(final AffineTransform transform) + { + return new PathIterator() { - xpoints[i] += dx; - xpoints[i] += dy; - } - - calculateBounds(); -} - -/*************************************************************************/ - -/** - * Adds the specified endpoint to the polygon. - * - * @param x The X coordinate of the point to add. - * @param y The Y coordiante of the point to add. - */ -public void -addPoint(int x, int y) -{ - int newxpoints[] = new int[npoints + 1]; - int newypoints[] = new int[npoints + 1]; - - System.arraycopy(xpoints, 0, newxpoints, 0, npoints); - System.arraycopy(ypoints, 0, newypoints, 0, npoints); - - newxpoints[npoints] = x; - newypoints[npoints] = y; - - xpoints = newxpoints; - ypoints = newypoints; - ++npoints; -} - -/*************************************************************************/ - -/** - * Returns the bounding box of this polygon. This is the smallest - * rectangle with sides parallel to the X axis that will contain this - * polygon. - * - * @return The bounding box for this polygon. - */ -public Rectangle -getBounds() -{ - return(bounds); -} - -/*************************************************************************/ - -/** - * Returns the bounding box of this polygon. This is the smallest - * rectangle with sides parallel to the X axis that will contain this - * polygon. - * - * @return The bounding box for this polygon. - * - * @deprecated This method has been replaced by <code>getBounds()</code>. - */ -public Rectangle -getBoundingBox() -{ - return(bounds); -} - -/*************************************************************************/ - -/** - * Tests whether or not the specified point is inside this polygon. - * - * @param x The X coordinate of the point to test. - * @param y the Y coordinate of the point to test. - * - * @return <code>true</code> if the point is inside this polygon, - * <code>false</code> otherwise. - */ -public boolean -contains(int x, int y) -{ - // Is inside bounding box. - if (!bounds.contains(x, y)) - return(false); - - int sign = 0; - for (int i = 0; i < npoints; i ++) - { - int nx = xpoints[(i + 1) % npoints] - xpoints[i]; - int ny = ypoints[(i + 1) % npoints] - ypoints[i]; - - int dx = x - xpoints[i]; - int dy = y - ypoints[i]; - - int val = (dx*nx) + (dy*nx); - - if (sign == 0) - { - if (val < 1) - sign = -1; - else if (val > 1) - sign = 1; - } - - if ((val > 1) && (sign < 1)) - return(false); - if ((val < 1) && (sign > 1)) - return(false); - } - - return(true); -} - -/*************************************************************************/ - -/** - * Tests whether or not the specified point is inside this polygon. - * - * @param x The X coordinate of the point to test. - * @param y the Y coordinate of the point to test. - * - * @return <code>true</code> if the point is inside this polygon, - * <code>false</code> otherwise. - * - * @deprecated This method has been replaced by <code>contains()</code>. - */ -public boolean -inside(int x, int y) -{ - return(contains(x, y)); -} - -} // class Polygon - + /** The current vertex of iteration. */ + private int vertex; + + public int getWindingRule() + { + return WIND_EVEN_ODD; + } + + public boolean isDone() + { + return vertex >= npoints; + } + + public void next() + { + vertex++; + } + + public int currentSegment(float[] coords) + { + if (vertex >= npoints) + return SEG_CLOSE; + coords[0] = xpoints[vertex]; + coords[1] = ypoints[vertex]; + if (transform != null) + transform.transform(coords, 0, coords, 0, 1); + return SEG_LINETO; + } + + public int currentSegment(double[] coords) + { + if (vertex >= npoints) + return SEG_CLOSE; + coords[0] = xpoints[vertex]; + coords[1] = ypoints[vertex]; + if (transform != null) + transform.transform(coords, 0, coords, 0, 1); + return SEG_LINETO; + } + }; + } + + /** + * Return an iterator along the flattened version of the shape boundary. + * Since rectangles are already flat, the flatness parameter is ignored, and + * the resulting iterator only has SEG_LINETO and SEG_CLOSE points. If the + * optional transform is provided, the iterator is transformed accordingly. + * Each call returns a new object, independent from others in use. This + * class is not threadsafe to begin with, so the path iterator is not either. + * + * @param transform an optional transform to apply to the iterator + * @param double the maximum distance for deviation from the real boundary + * @return a new iterator over the boundary + * @since 1.2 + */ + public PathIterator getPathIterator(AffineTransform transform, + double flatness) + { + return getPathIterator(transform); + } + + /** + * Helper for contains, which caches a condensed version of the polygon. + * This condenses all colinear points, so that consecutive segments in + * the condensed version always have different slope. + * + * @return true if the condensed polygon has area + * @see #condensed + * @see #contains(double, double) + */ + private boolean condense() + { + if (npoints <= 2) + return false; + if (condensed != null) + return condensed[0] > 2; + condensed = new int[npoints * 2 + 1]; + int curx = xpoints[npoints - 1]; + int cury = ypoints[npoints - 1]; + double curslope = Double.NaN; + int count = 0; + outer: + for (int i = 0; i < npoints; i++) + { + int priorx = curx; + int priory = cury; + double priorslope = curslope; + curx = xpoints[i]; + cury = ypoints[i]; + while (curx == priorx && cury == priory) + { + if (++i == npoints) + break outer; + curx = xpoints[i]; + cury = ypoints[i]; + } + curslope = (curx == priorx ? Double.POSITIVE_INFINITY + : (double) (cury - priory) / (curx - priorx)); + if (priorslope == curslope) + { + if (count > 1 && condensed[(count << 1) - 3] == curx + && condensed[(count << 1) - 2] == cury) + { + count--; + continue; + } + } + else + count++; + condensed[(count << 1) - 1] = curx; + condensed[count << 1] = cury; + } + condensed[0] = count; + return count > 2; + } +} // class Polygon |