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iText, a free Java-PDF library
/*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You under the Apache License, Version 2.0
* (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*
* This code was originally part of the Apache Harmony project.
* The Apache Harmony project has been discontinued.
* That's why we imported the code into iText.
*/
/**
* @author Denis M. Kishenko
*/
package com.itextpdf.awt.geom.gl;
import com.itextpdf.awt.geom.PathIterator;
import com.itextpdf.awt.geom.Shape;
public class Crossing {
/**
* Allowable tolerance for bounds comparison
*/
static final double DELTA = 1E-5;
/**
* If roots have distance less then ROOT_DELTA
they are double
*/
static final double ROOT_DELTA = 1E-10;
/**
* Rectangle cross segment
*/
public static final int CROSSING = 255;
/**
* Unknown crossing result
*/
static final int UNKNOWN = 254;
/**
* Solves quadratic equation
* @param eqn - the coefficients of the equation
* @param res - the roots of the equation
* @return a number of roots
*/
public static int solveQuad(double eqn[], double res[]) {
double a = eqn[2];
double b = eqn[1];
double c = eqn[0];
int rc = 0;
if (a == 0.0) {
if (b == 0.0) {
return -1;
}
res[rc++] = -c / b;
} else {
double d = b * b - 4.0 * a * c;
// d < 0.0
if (d < 0.0) {
return 0;
}
d = Math.sqrt(d);
res[rc++] = (- b + d) / (a * 2.0);
// d != 0.0
if (d != 0.0) {
res[rc++] = (- b - d) / (a * 2.0);
}
}
return fixRoots(res, rc);
}
/**
* Solves cubic equation
* @param eqn - the coefficients of the equation
* @param res - the roots of the equation
* @return a number of roots
*/
public static int solveCubic(double eqn[], double res[]) {
double d = eqn[3];
if (d == 0) {
return solveQuad(eqn, res);
}
double a = eqn[2] / d;
double b = eqn[1] / d;
double c = eqn[0] / d;
int rc = 0;
double Q = (a * a - 3.0 * b) / 9.0;
double R = (2.0 * a * a * a - 9.0 * a * b + 27.0 * c) / 54.0;
double Q3 = Q * Q * Q;
double R2 = R * R;
double n = - a / 3.0;
if (R2 < Q3) {
double t = Math.acos(R / Math.sqrt(Q3)) / 3.0;
double p = 2.0 * Math.PI / 3.0;
double m = -2.0 * Math.sqrt(Q);
res[rc++] = m * Math.cos(t) + n;
res[rc++] = m * Math.cos(t + p) + n;
res[rc++] = m * Math.cos(t - p) + n;
} else {
// Debug.println("R2 >= Q3 (" + R2 + "/" + Q3 + ")");
double A = Math.pow(Math.abs(R) + Math.sqrt(R2 - Q3), 1.0 / 3.0);
if (R > 0.0) {
A = -A;
}
// if (A == 0.0) {
if (-ROOT_DELTA < A && A < ROOT_DELTA) {
res[rc++] = n;
} else {
double B = Q / A;
res[rc++] = A + B + n;
// if (R2 == Q3) {
double delta = R2 - Q3;
if (-ROOT_DELTA < delta && delta < ROOT_DELTA) {
res[rc++] = - (A + B) / 2.0 + n;
}
}
}
return fixRoots(res, rc);
}
/**
* Excludes double roots. Roots are double if they lies enough close with each other.
* @param res - the roots
* @param rc - the roots count
* @return new roots count
*/
static int fixRoots(double res[], int rc) {
int tc = 0;
for(int i = 0; i < rc; i++) {
out: {
for(int j = i + 1; j < rc; j++) {
if (isZero(res[i] - res[j])) {
break out;
}
}
res[tc++] = res[i];
}
}
return tc;
}
/**
* QuadCurve class provides basic functionality to find curve crossing and calculating bounds
*/
public static class QuadCurve {
double ax, ay, bx, by;
double Ax, Ay, Bx, By;
public QuadCurve(double x1, double y1, double cx, double cy, double x2, double y2) {
ax = x2 - x1;
ay = y2 - y1;
bx = cx - x1;
by = cy - y1;
Bx = bx + bx; // Bx = 2.0 * bx
Ax = ax - Bx; // Ax = ax - 2.0 * bx
By = by + by; // By = 2.0 * by
Ay = ay - By; // Ay = ay - 2.0 * by
}
int cross(double res[], int rc, double py1, double py2) {
int cross = 0;
for (int i = 0; i < rc; i++) {
double t = res[i];
// CURVE-OUTSIDE
if (t < -DELTA || t > 1 + DELTA) {
continue;
}
// CURVE-START
if (t < DELTA) {
if (py1 < 0.0 && (bx != 0.0 ? bx : ax - bx) < 0.0) {
cross--;
}
continue;
}
// CURVE-END
if (t > 1 - DELTA) {
if (py1 < ay && (ax != bx ? ax - bx : bx) > 0.0) {
cross++;
}
continue;
}
// CURVE-INSIDE
double ry = t * (t * Ay + By);
// ry = t * t * Ay + t * By
if (ry > py2) {
double rxt = t * Ax + bx;
// rxt = 2.0 * t * Ax + Bx = 2.0 * t * Ax + 2.0 * bx
if (rxt > -DELTA && rxt < DELTA) {
continue;
}
cross += rxt > 0.0 ? 1 : -1;
}
} // for
return cross;
}
int solvePoint(double res[], double px) {
double eqn[] = {-px, Bx, Ax};
return solveQuad(eqn, res);
}
int solveExtrem(double res[]) {
int rc = 0;
if (Ax != 0.0) {
res[rc++] = - Bx / (Ax + Ax);
}
if (Ay != 0.0) {
res[rc++] = - By / (Ay + Ay);
}
return rc;
}
int addBound(double bound[], int bc, double res[], int rc, double minX, double maxX, boolean changeId, int id) {
for(int i = 0; i < rc; i++) {
double t = res[i];
if (t > -DELTA && t < 1 + DELTA) {
double rx = t * (t * Ax + Bx);
if (minX <= rx && rx <= maxX) {
bound[bc++] = t;
bound[bc++] = rx;
bound[bc++] = t * (t * Ay + By);
bound[bc++] = id;
if (changeId) {
id++;
}
}
}
}
return bc;
}
}
/**
* CubicCurve class provides basic functionality to find curve crossing and calculating bounds
*/
public static class CubicCurve {
double ax, ay, bx, by, cx, cy;
double Ax, Ay, Bx, By, Cx, Cy;
double Ax3, Bx2;
public CubicCurve(double x1, double y1, double cx1, double cy1, double cx2, double cy2, double x2, double y2) {
ax = x2 - x1;
ay = y2 - y1;
bx = cx1 - x1;
by = cy1 - y1;
cx = cx2 - x1;
cy = cy2 - y1;
Cx = bx + bx + bx; // Cx = 3.0 * bx
Bx = cx + cx + cx - Cx - Cx; // Bx = 3.0 * cx - 6.0 * bx
Ax = ax - Bx - Cx; // Ax = ax - 3.0 * cx + 3.0 * bx
Cy = by + by + by; // Cy = 3.0 * by
By = cy + cy + cy - Cy - Cy; // By = 3.0 * cy - 6.0 * by
Ay = ay - By - Cy; // Ay = ay - 3.0 * cy + 3.0 * by
Ax3 = Ax + Ax + Ax;
Bx2 = Bx + Bx;
}
int cross(double res[], int rc, double py1, double py2) {
int cross = 0;
for (int i = 0; i < rc; i++) {
double t = res[i];
// CURVE-OUTSIDE
if (t < -DELTA || t > 1 + DELTA) {
continue;
}
// CURVE-START
if (t < DELTA) {
if (py1 < 0.0 && (bx != 0.0 ? bx : (cx != bx ? cx - bx : ax - cx)) < 0.0) {
cross--;
}
continue;
}
// CURVE-END
if (t > 1 - DELTA) {
if (py1 < ay && (ax != cx ? ax - cx : (cx != bx ? cx - bx : bx)) > 0.0) {
cross++;
}
continue;
}
// CURVE-INSIDE
double ry = t * (t * (t * Ay + By) + Cy);
// ry = t * t * t * Ay + t * t * By + t * Cy
if (ry > py2) {
double rxt = t * (t * Ax3 + Bx2) + Cx;
// rxt = 3.0 * t * t * Ax + 2.0 * t * Bx + Cx
if (rxt > -DELTA && rxt < DELTA) {
rxt = t * (Ax3 + Ax3) + Bx2;
// rxt = 6.0 * t * Ax + 2.0 * Bx
if (rxt < -DELTA || rxt > DELTA) {
// Inflection point
continue;
}
rxt = ax;
}
cross += rxt > 0.0 ? 1 : -1;
}
} //for
return cross;
}
int solvePoint(double res[], double px) {
double eqn[] = {-px, Cx, Bx, Ax};
return solveCubic(eqn, res);
}
int solveExtremX(double res[]) {
double eqn[] = {Cx, Bx2, Ax3};
return solveQuad(eqn, res);
}
int solveExtremY(double res[]) {
double eqn[] = {Cy, By + By, Ay + Ay + Ay};
return solveQuad(eqn, res);
}
int addBound(double bound[], int bc, double res[], int rc, double minX, double maxX, boolean changeId, int id) {
for(int i = 0; i < rc; i++) {
double t = res[i];
if (t > -DELTA && t < 1 + DELTA) {
double rx = t * (t * (t * Ax + Bx) + Cx);
if (minX <= rx && rx <= maxX) {
bound[bc++] = t;
bound[bc++] = rx;
bound[bc++] = t * (t * (t * Ay + By) + Cy);
bound[bc++] = id;
if (changeId) {
id++;
}
}
}
}
return bc;
}
}
/**
* Returns how many times ray from point (x,y) cross line.
*/
public static int crossLine(double x1, double y1, double x2, double y2, double x, double y) {
// LEFT/RIGHT/UP/EMPTY
if ((x < x1 && x < x2) ||
(x > x1 && x > x2) ||
(y > y1 && y > y2) ||
(x1 == x2))
{
return 0;
}
// DOWN
if (y < y1 && y < y2) {
} else {
// INSIDE
if ((y2 - y1) * (x - x1) / (x2 - x1) <= y - y1) {
// INSIDE-UP
return 0;
}
}
// START
if (x == x1) {
return x1 < x2 ? 0 : -1;
}
// END
if (x == x2) {
return x1 < x2 ? 1 : 0;
}
// INSIDE-DOWN
return x1 < x2 ? 1 : -1;
}
/**
* Returns how many times ray from point (x,y) cross quard curve
*/
public static int crossQuad(double x1, double y1, double cx, double cy, double x2, double y2, double x, double y) {
// LEFT/RIGHT/UP/EMPTY
if ((x < x1 && x < cx && x < x2) ||
(x > x1 && x > cx && x > x2) ||
(y > y1 && y > cy && y > y2) ||
(x1 == cx && cx == x2))
{
return 0;
}
// DOWN
if (y < y1 && y < cy && y < y2 && x != x1 && x != x2) {
if (x1 < x2) {
return x1 < x && x < x2 ? 1 : 0;
}
return x2 < x && x < x1 ? -1 : 0;
}
// INSIDE
QuadCurve c = new QuadCurve(x1, y1, cx, cy, x2, y2);
double px = x - x1;
double py = y - y1;
double res[] = new double[3];
int rc = c.solvePoint(res, px);
return c.cross(res, rc, py, py);
}
/**
* Returns how many times ray from point (x,y) cross cubic curve
*/
public static int crossCubic(double x1, double y1, double cx1, double cy1, double cx2, double cy2, double x2, double y2, double x, double y) {
// LEFT/RIGHT/UP/EMPTY
if ((x < x1 && x < cx1 && x < cx2 && x < x2) ||
(x > x1 && x > cx1 && x > cx2 && x > x2) ||
(y > y1 && y > cy1 && y > cy2 && y > y2) ||
(x1 == cx1 && cx1 == cx2 && cx2 == x2))
{
return 0;
}
// DOWN
if (y < y1 && y < cy1 && y < cy2 && y < y2 && x != x1 && x != x2) {
if (x1 < x2) {
return x1 < x && x < x2 ? 1 : 0;
}
return x2 < x && x < x1 ? -1 : 0;
}
// INSIDE
CubicCurve c = new CubicCurve(x1, y1, cx1, cy1, cx2, cy2, x2, y2);
double px = x - x1;
double py = y - y1;
double res[] = new double[3];
int rc = c.solvePoint(res, px);
return c.cross(res, rc, py, py);
}
/**
* Returns how many times ray from point (x,y) cross path
*/
public static int crossPath(PathIterator p, double x, double y) {
int cross = 0;
double mx, my, cx, cy;
mx = my = cx = cy = 0.0;
double coords[] = new double[6];
while (!p.isDone()) {
switch (p.currentSegment(coords)) {
case PathIterator.SEG_MOVETO:
if (cx != mx || cy != my) {
cross += crossLine(cx, cy, mx, my, x, y);
}
mx = cx = coords[0];
my = cy = coords[1];
break;
case PathIterator.SEG_LINETO:
cross += crossLine(cx, cy, cx = coords[0], cy = coords[1], x, y);
break;
case PathIterator.SEG_QUADTO:
cross += crossQuad(cx, cy, coords[0], coords[1], cx = coords[2], cy = coords[3], x, y);
break;
case PathIterator.SEG_CUBICTO:
cross += crossCubic(cx, cy, coords[0], coords[1], coords[2], coords[3], cx = coords[4], cy = coords[5], x, y);
break;
case PathIterator.SEG_CLOSE:
if (cy != my || cx != mx) {
cross += crossLine(cx, cy, cx = mx, cy = my, x, y);
}
break;
}
// checks if the point (x,y) is the vertex of shape with PathIterator p
if (x == cx && y == cy) {
cross = 0;
cy = my;
break;
}
p.next();
}
if (cy != my) {
cross += crossLine(cx, cy, mx, my, x, y);
}
return cross;
}
/**
* Returns how many times ray from point (x,y) cross shape
*/
public static int crossShape(Shape s, double x, double y) {
if (!s.getBounds2D().contains(x, y)) {
return 0;
}
return crossPath(s.getPathIterator(null), x, y);
}
/**
* Returns true if value enough small
*/
public static boolean isZero(double val) {
return -DELTA < val && val < DELTA;
}
/**
* Sort bound array
*/
static void sortBound(double bound[], int bc) {
for(int i = 0; i < bc - 4; i += 4) {
int k = i;
for(int j = i + 4; j < bc; j += 4) {
if (bound[k] > bound[j]) {
k = j;
}
}
if (k != i) {
double tmp = bound[i];
bound[i] = bound[k];
bound[k] = tmp;
tmp = bound[i + 1];
bound[i + 1] = bound[k + 1];
bound[k + 1] = tmp;
tmp = bound[i + 2];
bound[i + 2] = bound[k + 2];
bound[k + 2] = tmp;
tmp = bound[i + 3];
bound[i + 3] = bound[k + 3];
bound[k + 3] = tmp;
}
}
}
/**
* Returns are bounds intersect or not intersect rectangle
*/
static int crossBound(double bound[], int bc, double py1, double py2) {
// LEFT/RIGHT
if (bc == 0) {
return 0;
}
// Check Y coordinate
int up = 0;
int down = 0;
for(int i = 2; i < bc; i += 4) {
if (bound[i] < py1) {
up++;
continue;
}
if (bound[i] > py2) {
down++;
continue;
}
return CROSSING;
}
// UP
if (down == 0) {
return 0;
}
if (up != 0) {
// bc >= 2
sortBound(bound, bc);
boolean sign = bound[2] > py2;
for(int i = 6; i < bc; i += 4) {
boolean sign2 = bound[i] > py2;
if (sign != sign2 && bound[i + 1] != bound[i - 3]) {
return CROSSING;
}
sign = sign2;
}
}
return UNKNOWN;
}
/**
* Returns how many times rectangle stripe cross line or the are intersect
*/
public static int intersectLine(double x1, double y1, double x2, double y2, double rx1, double ry1, double rx2, double ry2) {
// LEFT/RIGHT/UP
if ((rx2 < x1 && rx2 < x2) ||
(rx1 > x1 && rx1 > x2) ||
(ry1 > y1 && ry1 > y2))
{
return 0;
}
// DOWN
if (ry2 < y1 && ry2 < y2) {
} else {
// INSIDE
if (x1 == x2) {
return CROSSING;
}
// Build bound
double bx1, bx2;
if (x1 < x2) {
bx1 = x1 < rx1 ? rx1 : x1;
bx2 = x2 < rx2 ? x2 : rx2;
} else {
bx1 = x2 < rx1 ? rx1 : x2;
bx2 = x1 < rx2 ? x1 : rx2;
}
double k = (y2 - y1) / (x2 - x1);
double by1 = k * (bx1 - x1) + y1;
double by2 = k * (bx2 - x1) + y1;
// BOUND-UP
if (by1 < ry1 && by2 < ry1) {
return 0;
}
// BOUND-DOWN
if (by1 > ry2 && by2 > ry2) {
} else {
return CROSSING;
}
}
// EMPTY
if (x1 == x2) {
return 0;
}
// CURVE-START
if (rx1 == x1) {
return x1 < x2 ? 0 : -1;
}
// CURVE-END
if (rx1 == x2) {
return x1 < x2 ? 1 : 0;
}
if (x1 < x2) {
return x1 < rx1 && rx1 < x2 ? 1 : 0;
}
return x2 < rx1 && rx1 < x1 ? -1 : 0;
}
/**
* Returns how many times rectangle stripe cross quad curve or the are intersect
*/
public static int intersectQuad(double x1, double y1, double cx, double cy, double x2, double y2, double rx1, double ry1, double rx2, double ry2) {
// LEFT/RIGHT/UP ------------------------------------------------------
if ((rx2 < x1 && rx2 < cx && rx2 < x2) ||
(rx1 > x1 && rx1 > cx && rx1 > x2) ||
(ry1 > y1 && ry1 > cy && ry1 > y2))
{
return 0;
}
// DOWN ---------------------------------------------------------------
if (ry2 < y1 && ry2 < cy && ry2 < y2 && rx1 != x1 && rx1 != x2) {
if (x1 < x2) {
return x1 < rx1 && rx1 < x2 ? 1 : 0;
}
return x2 < rx1 && rx1 < x1 ? -1 : 0;
}
// INSIDE -------------------------------------------------------------
QuadCurve c = new QuadCurve(x1, y1, cx, cy, x2, y2);
double px1 = rx1 - x1;
double py1 = ry1 - y1;
double px2 = rx2 - x1;
double py2 = ry2 - y1;
double res1[] = new double[3];
double res2[] = new double[3];
int rc1 = c.solvePoint(res1, px1);
int rc2 = c.solvePoint(res2, px2);
// INSIDE-LEFT/RIGHT
if (rc1 == 0 && rc2 == 0) {
return 0;
}
// Build bound --------------------------------------------------------
double minX = px1 - DELTA;
double maxX = px2 + DELTA;
double bound[] = new double[28];
int bc = 0;
// Add roots
bc = c.addBound(bound, bc, res1, rc1, minX, maxX, false, 0);
bc = c.addBound(bound, bc, res2, rc2, minX, maxX, false, 1);
// Add extremal points`
rc2 = c.solveExtrem(res2);
bc = c.addBound(bound, bc, res2, rc2, minX, maxX, true, 2);
// Add start and end
if (rx1 < x1 && x1 < rx2) {
bound[bc++] = 0.0;
bound[bc++] = 0.0;
bound[bc++] = 0.0;
bound[bc++] = 4;
}
if (rx1 < x2 && x2 < rx2) {
bound[bc++] = 1.0;
bound[bc++] = c.ax;
bound[bc++] = c.ay;
bound[bc++] = 5;
}
// End build bound ----------------------------------------------------
int cross = crossBound(bound, bc, py1, py2);
if (cross != UNKNOWN) {
return cross;
}
return c.cross(res1, rc1, py1, py2);
}
/**
* Returns how many times rectangle stripe cross cubic curve or the are intersect
*/
public static int intersectCubic(double x1, double y1, double cx1, double cy1, double cx2, double cy2, double x2, double y2, double rx1, double ry1, double rx2, double ry2) {
// LEFT/RIGHT/UP
if ((rx2 < x1 && rx2 < cx1 && rx2 < cx2 && rx2 < x2) ||
(rx1 > x1 && rx1 > cx1 && rx1 > cx2 && rx1 > x2) ||
(ry1 > y1 && ry1 > cy1 && ry1 > cy2 && ry1 > y2))
{
return 0;
}
// DOWN
if (ry2 < y1 && ry2 < cy1 && ry2 < cy2 && ry2 < y2 && rx1 != x1 && rx1 != x2) {
if (x1 < x2) {
return x1 < rx1 && rx1 < x2 ? 1 : 0;
}
return x2 < rx1 && rx1 < x1 ? -1 : 0;
}
// INSIDE
CubicCurve c = new CubicCurve(x1, y1, cx1, cy1, cx2, cy2, x2, y2);
double px1 = rx1 - x1;
double py1 = ry1 - y1;
double px2 = rx2 - x1;
double py2 = ry2 - y1;
double res1[] = new double[3];
double res2[] = new double[3];
int rc1 = c.solvePoint(res1, px1);
int rc2 = c.solvePoint(res2, px2);
// LEFT/RIGHT
if (rc1 == 0 && rc2 == 0) {
return 0;
}
double minX = px1 - DELTA;
double maxX = px2 + DELTA;
// Build bound --------------------------------------------------------
double bound[] = new double[40];
int bc = 0;
// Add roots
bc = c.addBound(bound, bc, res1, rc1, minX, maxX, false, 0);
bc = c.addBound(bound, bc, res2, rc2, minX, maxX, false, 1);
// Add extrimal points
rc2 = c.solveExtremX(res2);
bc = c.addBound(bound, bc, res2, rc2, minX, maxX, true, 2);
rc2 = c.solveExtremY(res2);
bc = c.addBound(bound, bc, res2, rc2, minX, maxX, true, 4);
// Add start and end
if (rx1 < x1 && x1 < rx2) {
bound[bc++] = 0.0;
bound[bc++] = 0.0;
bound[bc++] = 0.0;
bound[bc++] = 6;
}
if (rx1 < x2 && x2 < rx2) {
bound[bc++] = 1.0;
bound[bc++] = c.ax;
bound[bc++] = c.ay;
bound[bc++] = 7;
}
// End build bound ----------------------------------------------------
int cross = crossBound(bound, bc, py1, py2);
if (cross != UNKNOWN) {
return cross;
}
return c.cross(res1, rc1, py1, py2);
}
/**
* Returns how many times rectangle stripe cross path or the are intersect
*/
public static int intersectPath(PathIterator p, double x, double y, double w, double h) {
int cross = 0;
int count;
double mx, my, cx, cy;
mx = my = cx = cy = 0.0;
double coords[] = new double[6];
double rx1 = x;
double ry1 = y;
double rx2 = x + w;
double ry2 = y + h;
while (!p.isDone()) {
count = 0;
switch (p.currentSegment(coords)) {
case PathIterator.SEG_MOVETO:
if (cx != mx || cy != my) {
count = intersectLine(cx, cy, mx, my, rx1, ry1, rx2, ry2);
}
mx = cx = coords[0];
my = cy = coords[1];
break;
case PathIterator.SEG_LINETO:
count = intersectLine(cx, cy, cx = coords[0], cy = coords[1], rx1, ry1, rx2, ry2);
break;
case PathIterator.SEG_QUADTO:
count = intersectQuad(cx, cy, coords[0], coords[1], cx = coords[2], cy = coords[3], rx1, ry1, rx2, ry2);
break;
case PathIterator.SEG_CUBICTO:
count = intersectCubic(cx, cy, coords[0], coords[1], coords[2], coords[3], cx = coords[4], cy = coords[5], rx1, ry1, rx2, ry2);
break;
case PathIterator.SEG_CLOSE:
if (cy != my || cx != mx) {
count = intersectLine(cx, cy, mx, my, rx1, ry1, rx2, ry2);
}
cx = mx;
cy = my;
break;
}
if (count == CROSSING) {
return CROSSING;
}
cross += count;
p.next();
}
if (cy != my) {
count = intersectLine(cx, cy, mx, my, rx1, ry1, rx2, ry2);
if (count == CROSSING) {
return CROSSING;
}
cross += count;
}
return cross;
}
/**
* Returns how many times rectangle stripe cross shape or the are intersect
*/
public static int intersectShape(Shape s, double x, double y, double w, double h) {
if (!s.getBounds2D().intersects(x, y, w, h)) {
return 0;
}
return intersectPath(s.getPathIterator(null), x, y, w, h);
}
/**
* Returns true if cross count correspond inside location for non zero path rule
*/
public static boolean isInsideNonZero(int cross) {
return cross != 0;
}
/**
* Returns true if cross count correspond inside location for even-odd path rule
*/
public static boolean isInsideEvenOdd(int cross) {
return (cross & 1) != 0;
}
}
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