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-rw-r--r--turtle2d/src/jogamp/graph/math/plane/Crossing.java897
1 files changed, 897 insertions, 0 deletions
diff --git a/turtle2d/src/jogamp/graph/math/plane/Crossing.java b/turtle2d/src/jogamp/graph/math/plane/Crossing.java
new file mode 100644
index 000000000..8f8638632
--- /dev/null
+++ b/turtle2d/src/jogamp/graph/math/plane/Crossing.java
@@ -0,0 +1,897 @@
+/*
+ * 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.
+ */
+/**
+ * @author Denis M. Kishenko
+ */
+package jogamp.graph.math.plane;
+
+import jogamp.graph.geom.plane.Path2D;
+import jogamp.graph.geom.plane.PathIterator;
+import jogamp.graph.math.MathFloat;
+
+
+public class Crossing {
+
+ /**
+ * Allowable tolerance for bounds comparison
+ */
+ static final float DELTA = (float) 1E-5;
+
+ /**
+ * If roots have distance less then <code>ROOT_DELTA</code> they are double
+ */
+ static final float ROOT_DELTA = (float) 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(float eqn[], float res[]) {
+ float a = eqn[2];
+ float b = eqn[1];
+ float c = eqn[0];
+ int rc = 0;
+ if (a == 0.0) {
+ if (b == 0.0) {
+ return -1;
+ }
+ res[rc++] = -c / b;
+ } else {
+ float d = b * b - 4.0f * a * c;
+ // d < 0.0
+ if (d < 0.0) {
+ return 0;
+ }
+ d = MathFloat.sqrt(d);
+ res[rc++] = (- b + d) / (a * 2.0f);
+ // d != 0.0
+ if (d != 0.0) {
+ res[rc++] = (- b - d) / (a * 2.0f);
+ }
+ }
+ 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(float eqn[], float res[]) {
+ float d = eqn[3];
+ if (d == 0) {
+ return solveQuad(eqn, res);
+ }
+ float a = eqn[2] / d;
+ float b = eqn[1] / d;
+ float c = eqn[0] / d;
+ int rc = 0;
+
+ float Q = (a * a - 3.0f * b) / 9.0f;
+ float R = (2.0f * a * a * a - 9.0f * a * b + 27.0f * c) / 54.0f;
+ float Q3 = Q * Q * Q;
+ float R2 = R * R;
+ float n = - a / 3.0f;
+
+ if (R2 < Q3) {
+ float t = MathFloat.acos(R / MathFloat.sqrt(Q3)) / 3.0f;
+ float p = 2.0f * MathFloat.PI / 3.0f;
+ float m = -2.0f * MathFloat.sqrt(Q);
+ res[rc++] = m * MathFloat.cos(t) + n;
+ res[rc++] = m * MathFloat.cos(t + p) + n;
+ res[rc++] = m * MathFloat.cos(t - p) + n;
+ } else {
+// Debug.println("R2 >= Q3 (" + R2 + "/" + Q3 + ")");
+ float A = MathFloat.pow(MathFloat.abs(R) + MathFloat.sqrt(R2 - Q3), 1.0f / 3.0f);
+ if (R > 0.0) {
+ A = -A;
+ }
+// if (A == 0.0) {
+ if (-ROOT_DELTA < A && A < ROOT_DELTA) {
+ res[rc++] = n;
+ } else {
+ float B = Q / A;
+ res[rc++] = A + B + n;
+// if (R2 == Q3) {
+ float delta = R2 - Q3;
+ if (-ROOT_DELTA < delta && delta < ROOT_DELTA) {
+ res[rc++] = - (A + B) / 2.0f + n;
+ }
+ }
+
+ }
+ return fixRoots(res, rc);
+ }
+
+ /**
+ * Excludes float roots. Roots are float if they lies enough close with each other.
+ * @param res - the roots
+ * @param rc - the roots count
+ * @return new roots count
+ */
+ static int fixRoots(float 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 {
+
+ float ax, ay, bx, by;
+ float Ax, Ay, Bx, By;
+
+ public QuadCurve(float x1, float y1, float cx, float cy, float x2, float 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(float res[], int rc, float py1, float py2) {
+ int cross = 0;
+
+ for (int i = 0; i < rc; i++) {
+ float 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
+ float ry = t * (t * Ay + By);
+ // ry = t * t * Ay + t * By
+ if (ry > py2) {
+ float 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(float res[], float px) {
+ float eqn[] = {-px, Bx, Ax};
+ return solveQuad(eqn, res);
+ }
+
+ int solveExtrem(float 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(float bound[], int bc, float res[], int rc, float minX, float maxX, boolean changeId, int id) {
+ for(int i = 0; i < rc; i++) {
+ float t = res[i];
+ if (t > -DELTA && t < 1 + DELTA) {
+ float 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 {
+
+ float ax, ay, bx, by, cx, cy;
+ float Ax, Ay, Bx, By, Cx, Cy;
+ float Ax3, Bx2;
+
+ public CubicCurve(float x1, float y1, float cx1, float cy1, float cx2, float cy2, float x2, float 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(float res[], int rc, float py1, float py2) {
+ int cross = 0;
+ for (int i = 0; i < rc; i++) {
+ float 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
+ float ry = t * (t * (t * Ay + By) + Cy);
+ // ry = t * t * t * Ay + t * t * By + t * Cy
+ if (ry > py2) {
+ float 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(float res[], float px) {
+ float eqn[] = {-px, Cx, Bx, Ax};
+ return solveCubic(eqn, res);
+ }
+
+ int solveExtremX(float res[]) {
+ float eqn[] = {Cx, Bx2, Ax3};
+ return solveQuad(eqn, res);
+ }
+
+ int solveExtremY(float res[]) {
+ float eqn[] = {Cy, By + By, Ay + Ay + Ay};
+ return solveQuad(eqn, res);
+ }
+
+ int addBound(float bound[], int bc, float res[], int rc, float minX, float maxX, boolean changeId, int id) {
+ for(int i = 0; i < rc; i++) {
+ float t = res[i];
+ if (t > -DELTA && t < 1 + DELTA) {
+ float 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(float x1, float y1, float x2, float y2, float x, float 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(float x1, float y1, float cx, float cy, float x2, float y2, float x, float 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);
+ float px = x - x1;
+ float py = y - y1;
+ float res[] = new float[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(float x1, float y1, float cx1, float cy1, float cx2, float cy2, float x2, float y2, float x, float 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);
+ float px = x - x1;
+ float py = y - y1;
+ float res[] = new float[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, float x, float y) {
+ int cross = 0;
+ float mx, my, cx, cy;
+ mx = my = cx = cy = 0.0f;
+ float coords[] = new float[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(Path2D s, float x, float y) {
+ if (!s.getBounds2D().contains(x, y)) {
+ return 0;
+ }
+ return crossPath(s.iterator(null), x, y);
+ }
+
+ /**
+ * Returns true if value enough small
+ */
+ public static boolean isZero(float val) {
+ return -DELTA < val && val < DELTA;
+ }
+
+ /**
+ * Sort bound array
+ */
+ static void sortBound(float 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) {
+ float 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(float bound[], int bc, float py1, float 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(float x1, float y1, float x2, float y2, float rx1, float ry1, float rx2, float 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
+ float 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;
+ }
+ float k = (y2 - y1) / (x2 - x1);
+ float by1 = k * (bx1 - x1) + y1;
+ float 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(float x1, float y1, float cx, float cy, float x2, float y2, float rx1, float ry1, float rx2, float 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);
+ float px1 = rx1 - x1;
+ float py1 = ry1 - y1;
+ float px2 = rx2 - x1;
+ float py2 = ry2 - y1;
+
+ float res1[] = new float[3];
+ float res2[] = new float[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 --------------------------------------------------------
+ float minX = px1 - DELTA;
+ float maxX = px2 + DELTA;
+ float bound[] = new float[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++] = 0.0f;
+ bound[bc++] = 0.0f;
+ bound[bc++] = 0.0f;
+ bound[bc++] = 4;
+ }
+ if (rx1 < x2 && x2 < rx2) {
+ bound[bc++] = 1.0f;
+ 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(float x1, float y1, float cx1, float cy1, float cx2, float cy2, float x2, float y2, float rx1, float ry1, float rx2, float 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);
+ float px1 = rx1 - x1;
+ float py1 = ry1 - y1;
+ float px2 = rx2 - x1;
+ float py2 = ry2 - y1;
+
+ float res1[] = new float[3];
+ float res2[] = new float[3];
+ int rc1 = c.solvePoint(res1, px1);
+ int rc2 = c.solvePoint(res2, px2);
+
+ // LEFT/RIGHT
+ if (rc1 == 0 && rc2 == 0) {
+ return 0;
+ }
+
+ float minX = px1 - DELTA;
+ float maxX = px2 + DELTA;
+
+ // Build bound --------------------------------------------------------
+ float bound[] = new float[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++] = 0.0f;
+ bound[bc++] = 0.0f;
+ bound[bc++] = 0.0f;
+ bound[bc++] = 6;
+ }
+ if (rx1 < x2 && x2 < rx2) {
+ bound[bc++] = 1.0f;
+ 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, float x, float y, float w, float h) {
+
+ int cross = 0;
+ int count;
+ float mx, my, cx, cy;
+ mx = my = cx = cy = 0.0f;
+ float coords[] = new float[6];
+
+ float rx1 = x;
+ float ry1 = y;
+ float rx2 = x + w;
+ float 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(Path2D s, float x, float y, float w, float h) {
+ if (!s.getBounds2D().intersects(x, y, w, h)) {
+ return 0;
+ }
+ return intersectPath(s.iterator(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;
+ }
+}
generated by cgit v1.2.3 (git 2.39.1) at 2024-12-29 23:37:10 +0000