Java Utililty Methods Geometry Polygon

List of utility methods to do Geometry Polygon

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Geometry Polygon

Description

The list of methods to do Geometry Polygon are organized into topic(s).

Method

boolean boundingTest(Polygon p, int x, int y, int w, int h)
bounding Test

rect.setBounds(x, y, w, h);
return p.intersects(rect);

boolean inside_polygon(float[] xpts, float[] ypts, double ptx, double pty)
Tests if a point is inside a polygon.

int j, inside_flag = 0;
int numverts = xpts.length;
if (numverts <= 2)
 return false;
Point2D vtx0 = new Point2D.Float(), vtx1 = new Point2D.Float();
double dv0; 
int crossings = 0;
boolean xflag0 = false, yflag0 = false, yflag1 = false;
...

Polygon makeArea(Polygon polygon, int steps, int dX, int dY)
make Area

for (int i = steps - 1; i >= 0; --i) {
 polygon.addPoint(polygon.xpoints[i] + dX, polygon.ypoints[i] + dY);
return polygon;

int polyArea(Polygon target)
poly Area

int sum = 0;
for (int i = 0; i < target.npoints; i++) {
 sum = sum + target.xpoints[i] * target.ypoints[(i + 1) % target.npoints]
 - target.ypoints[i] * target.xpoints[(i + 1) % target.npoints];
return Math.abs(sum / 2);

Shape regularPolygon(int sides, double x, double y, double width, double height)
regular Polygon

Path2D poly = new Path2D.Double(Path2D.WIND_EVEN_ODD, 12);
width = width / 2;
height = height / 2;
x = x + width;
y = y + height;
Point2D.Double points[] = new Point2D.Double[sides];
for (int i = 0; i < sides; i++) {
 double x1 = circleX(sides, i) * width + x;
...

java.awt.Polygon sparsifyPolygon(java.awt.Polygon p, double minDistance)
sparsify Polygon

int n = p.npoints;
int[] xs = p.xpoints;
ArrayList<Integer> nxs = new ArrayList<Integer>(n);
int[] ys = p.ypoints;
ArrayList<Integer> nys = new ArrayList<Integer>(n);
nxs.add(xs[0]);
nys.add(ys[0]);
int px = xs[0];
...