/*
* $Id$
* This file is a part of the Arakhne Foundation Classes, http://www.arakhne.org/afc
*
* Copyright (c) 2000-2012 Stephane GALLAND.
* Copyright (c) 2005-10, Multiagent Team, Laboratoire Systemes et Transports,
* Universite de Technologie de Belfort-Montbeliard.
* Copyright (c) 2013-2016 The original authors, and other authors.
*
* Licensed 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.
*/
package org.arakhne.afc.math.geometry.d3.afp;
import org.arakhne.afc.math.MathConstants;
import org.arakhne.afc.math.MathUtil;
import org.arakhne.afc.math.geometry.PathElementType;
import org.arakhne.afc.math.geometry.d3.Point3D;
import org.arakhne.afc.vmutil.asserts.AssertMessages;
import org.arakhne.afc.vmutil.locale.Locale;
/** Shadow of a path that is used for computing the crossing values
* between a shape and the shadow.
*
* @author $Author: sgalland$
* @version $FullVersion$
* @mavengroupid $GroupId$
* @mavenartifactid $ArtifactId$
* @since 13.0
*/
class ClosestPointPathShadow3afp {
private final PathIterator3afp<?> pathIterator;
private final Point3D<?, ?> otherShapeClosestPoint = new InnerComputationPoint3afp();
private final Point3D<?, ?> shadowShapeClosestPoint = new InnerComputationPoint3afp();
private final Point3D<?, ?> temporaryPoint1 = new InnerComputationPoint3afp();
private final Point3D<?, ?> temporaryPoint2 = new InnerComputationPoint3afp();
private double minDistance = Double.POSITIVE_INFINITY;
private final double boundingMinX;
private final double boundingMinY;
//TODO private final double boundingMinZ;
//TODO private final double boundingMaxX;
private final double boundingMaxY;
//TODO private final double boundingMaxZ;
private boolean started;
private int crossings;
private boolean hasX4ymin;
private boolean hasX4ymax;
private double x4ymin;
private double x4ymax;
/** Construct new path shadow.
* @param pathIterator the iterator on the path that is constituting the shadow.
* @param bounds the bounds of the shadow.
*/
ClosestPointPathShadow3afp(PathIterator3afp<?> pathIterator, RectangularPrism3afp<?, ?, ?, ?, ?, ?> bounds) {
assert pathIterator != null : AssertMessages.notNullParameter(0);
assert bounds != null : AssertMessages.notNullParameter(1);
this.pathIterator = pathIterator;
this.boundingMinX = bounds.getMinX();
this.boundingMinY = bounds.getMinY();
this.boundingMaxY = bounds.getMaxY();
//TODO this.boundingMinZ = bounds.getMinZ();
//TODO this.boundingMaxX = bounds.getMaxX();
//TODO this.boundingMaxZ = bounds.getMaxZ();
}
/** Compute the crossings between this shadow and
* the given segment.
*
* @param crossings is the initial value of the crossings.
* @param x0 is the first point of the segment.
* @param y0 is the first point of the segment.
* @param z0 is the first point of the segment.
* @param x1 is the second point of the segment.
* @param y1 is the second point of the segment.
* @param z1 is the second point of the segment.
* @return the crossings or {@link MathConstants#SHAPE_INTERSECTS}.
*/
@SuppressWarnings("checkstyle:npathcomplexity")
public int computeCrossings(
int crossings,
double x0, double y0, double z0,
double x1, double y1, double z1) {
// The segment is intersecting the bounds of the shadow path.
// We must consider the shape of shadow path now.
this.x4ymin = this.boundingMinX;
this.x4ymax = this.boundingMinX;
this.crossings = 0;
this.hasX4ymin = false;
this.hasX4ymax = false;
final PathIterator3afp<?> iterator;
if (this.started) {
iterator = this.pathIterator.restartIterations();
} else {
this.started = true;
iterator = this.pathIterator;
}
discretizePathIterator(
iterator,
x0, y0, z0, x1, y1, z1);
// Test if the shape is intesecting the shadow shape.
if (this.crossings == MathConstants.SHAPE_INTERSECTS) {
// The given line is intersecting the path shape
return MathConstants.SHAPE_INTERSECTS;
}
// There is no intersection with the shadow path's shape.
// Compute the crossings with the minimum/maximum y borders.
int inc = 0;
if (this.hasX4ymin) {
++inc;
}
if (this.hasX4ymax) {
++inc;
}
final int numCrosses;
if (y0 < y1) {
numCrosses = inc;
} else {
numCrosses = -inc;
}
// Apply the previously computed crossings
return crossings + numCrosses;
}
@SuppressWarnings({"checkstyle:parameternumber", "checkstyle:cyclomaticcomplexity",
"checkstyle:npathcomplexity", "checkstyle:returncount"})
private void discretizePathIterator(
PathIterator3afp<?> pi,
double x1, double y1, double z1, double x2, double y2, double z2) {
if (!pi.hasNext() || this.crossings == MathConstants.SHAPE_INTERSECTS) {
return;
}
PathElement3afp element;
element = pi.next();
if (element.getType() != PathElementType.MOVE_TO) {
throw new IllegalArgumentException(Locale.getString(Path3afp.class, "E1")); //$NON-NLS-1$
}
Path3afp<?, ?, ?, ?, ?, ?> localPath;
double movx = element.getToX();
double movy = element.getToY();
double movz = element.getToZ();
double curx = movx;
double cury = movy;
double curz = movz;
double endx;
double endy;
double endz;
double distance;
while (pi.hasNext()) {
element = pi.next();
switch (element.getType()) {
case MOVE_TO:
movx = element.getToX();
curx = movx;
movy = element.getToY();
cury = movy;
movz = element.getToZ();
curz = movz;
break;
case LINE_TO:
endx = element.getToX();
endy = element.getToY();
endz = element.getToZ();
distance = Segment3afp.computeClosestPointToSegment(x1, y1, z1, x2, y2, z2, curx, cury, curz, endx, endy, endz,
this.temporaryPoint1, this.temporaryPoint2);
if (distance <= 0.) {
this.otherShapeClosestPoint.set(this.temporaryPoint1);
this.shadowShapeClosestPoint.set(this.temporaryPoint2);
this.crossings = MathConstants.SHAPE_INTERSECTS;
return;
} else if (distance < this.minDistance) {
this.minDistance = distance;
this.otherShapeClosestPoint.set(this.temporaryPoint1);
this.shadowShapeClosestPoint.set(this.temporaryPoint2);
}
crossSegmentTwoShadowLines(
curx, cury, curz,
endx, endy, endz,
x1, y1, z1, x2, y2, z2);
if (this.crossings == MathConstants.SHAPE_INTERSECTS) {
return;
}
curx = endx;
cury = endy;
curz = endz;
break;
case QUAD_TO:
endx = element.getToX();
endy = element.getToY();
endz = element.getToZ();
// only for local use.
localPath = pi.getGeomFactory().newPath(pi.getWindingRule());
localPath.moveTo(curx, cury, curz);
localPath.quadTo(
element.getCtrlX1(), element.getCtrlY1(), element.getCtrlZ1(),
endx, endy, endz);
discretizePathIterator(
localPath.getPathIterator(MathConstants.SPLINE_APPROXIMATION_RATIO),
x1, y1, z1, x2, y2, z2);
if (this.crossings == MathConstants.SHAPE_INTERSECTS) {
return;
}
curx = endx;
cury = endy;
curz = endz;
break;
case CURVE_TO:
endx = element.getToX();
endy = element.getToY();
endz = element.getToZ();
// only for local use.
localPath = pi.getGeomFactory().newPath(pi.getWindingRule());
localPath.moveTo(curx, cury, curz);
localPath.curveTo(
element.getCtrlX1(), element.getCtrlY1(), element.getCtrlZ1(),
element.getCtrlX2(), element.getCtrlY2(), element.getCtrlZ2(),
endx, endy, endz);
discretizePathIterator(
localPath.getPathIterator(MathConstants.SPLINE_APPROXIMATION_RATIO),
x1, y1, z1, x2, y2, z2);
if (this.crossings == MathConstants.SHAPE_INTERSECTS) {
return;
}
curx = endx;
cury = endy;
curz = endz;
break;
case ARC_TO:
endx = element.getToX();
endy = element.getToY();
endz = element.getToZ();
// only for local use.
localPath = pi.getGeomFactory().newPath(pi.getWindingRule());
localPath.moveTo(curx, cury, curz);
//localPath.arcTo(
// endx, endy,
// element.getRadiusX(), element.getRadiusY(),
// element.getRotationX(), element.getLargeArcFlag(),
// element.getSweepFlag());
discretizePathIterator(
localPath.getPathIterator(MathConstants.SPLINE_APPROXIMATION_RATIO),
x1, y1, z1, x2, y2, z2);
if (this.crossings == MathConstants.SHAPE_INTERSECTS) {
return;
}
curx = endx;
cury = endy;
curz = endz;
break;
case CLOSE:
if (cury != movy || curx != movx || curz != movz) {
distance = Segment3afp.computeClosestPointToSegment(x1, y1, z1, x2, y2, z2, curx, cury, curz, movx, movy,
movz, this.temporaryPoint1, this.temporaryPoint2);
if (distance <= 0.) {
this.otherShapeClosestPoint.set(this.temporaryPoint1);
this.shadowShapeClosestPoint.set(this.temporaryPoint2);
this.crossings = MathConstants.SHAPE_INTERSECTS;
return;
} else if (distance < this.minDistance) {
this.minDistance = distance;
this.otherShapeClosestPoint.set(this.temporaryPoint1);
this.shadowShapeClosestPoint.set(this.temporaryPoint2);
}
crossSegmentTwoShadowLines(
curx, cury, curz,
movx, movy, movz,
x1, y1, z1, x2, y2, z2);
}
if (this.crossings != 0) {
return;
}
curx = movx;
cury = movy;
curz = movz;
break;
default:
}
}
assert this.crossings != MathConstants.SHAPE_INTERSECTS;
if (curx != movx || cury != movy) {
// Assume that when is the path is open, only
// SHAPE_INTERSECTS may be return
this.crossings = 0;
}
}
private void setCrossingCoordinateForYMax(double x, double y) {
if (MathUtil.compareEpsilon(y, this.boundingMaxY) >= 0 && x > this.x4ymax) {
this.x4ymax = x;
this.hasX4ymax = true;
}
}
private void setCrossingCoordinateForYMin(double x, double y) {
if (MathUtil.compareEpsilon(y, this.boundingMinY) <= 0 && x > this.x4ymin) {
this.x4ymin = x;
this.hasX4ymin = true;
}
}
/** Determine where the segment is crossing the two shadow lines.
*
* @param shadowX0 x coordinate of the reference point of the first shadow line.
* @param shadowY0 y coordinate of the reference point of the first shadow line.
* @param shadowX1 x coordinate of the reference point of the second shadow line.
* @param shadowY1 y coordinate of the reference point of the second shadow line.
* @param sx0 x coordinate of the first point of the segment.
* @param sy0 y coordinate of the first point of the segment.
* @param sx1 x coordinate of the second point of the segment.
* @param sy1 y coordinate of the second point of the segment.
*/
@SuppressWarnings({"checkstyle:parameternumber", "checkstyle:cyclomaticcomplexity",
"checkstyle:npathcomplexity"})
private void crossSegmentTwoShadowLines(
double shadowX0, double shadowY0, double shadowZ0,
double shadowX1, double shadowY1, double shadowZ1,
double sx0, double sy0, double sz0,
double sx1, double sy1, double sz1) {
// Update the global bounds of the shadow.
final double shadowXmin = Math.min(shadowX0, shadowX1);
final double shadowXmax = Math.max(shadowX0, shadowX1);
final double shadowYmin = Math.min(shadowY0, shadowY1);
final double shadowYmax = Math.max(shadowY0, shadowY1);
if (sy0 < shadowYmin && sy1 < shadowYmin) {
// The segment is entirely at the bottom of the shadow.
return;
}
if (sy0 > shadowYmax && sy1 > shadowYmax) {
// The segment is entirely at the top of the shadow.
return;
}
if (sx0 < shadowXmin && sx1 < shadowXmin) {
// The segment is entirely at the left of the shadow.
return;
}
if (sx0 >= shadowXmax && sx1 >= shadowXmax) {
// The line is entirely at the right of the shadow
final double alpha = (sx1 - sx0) / (sy1 - sy0);
if (sy0 < sy1) {
if (sy0 <= shadowYmin) {
final double xintercept = sx0 + (shadowYmin - sy0) * alpha;
setCrossingCoordinateForYMin(xintercept, shadowYmin);
++this.crossings;
}
if (sy1 >= shadowYmax) {
final double xintercept = sx0 + (shadowYmax - sy0) * alpha;
setCrossingCoordinateForYMax(xintercept, shadowYmax);
++this.crossings;
}
} else {
if (sy1 <= shadowYmin) {
final double xintercept = sx0 + (shadowYmin - sy0) * alpha;
setCrossingCoordinateForYMin(xintercept, shadowYmin);
--this.crossings;
}
if (sy0 >= shadowYmax) {
final double xintercept = sx0 + (shadowYmax - sy0) * alpha;
setCrossingCoordinateForYMax(xintercept, shadowYmax);
--this.crossings;
}
}
} else if (Segment3afp.intersectsSegmentSegmentWithoutEnds(
shadowX0, shadowY0, shadowZ0, shadowX1, shadowY1, shadowZ1,
sx0, sy0, sz0, sx1, sy1, sz1)) {
// The segment is intersecting the shadowed segment.
this.crossings = MathConstants.SHAPE_INTERSECTS;
} else {
final int side1;
final int side2;
if (shadowY0 <= shadowY1) {
side1 = Segment3afp.computeSideLinePoint(
shadowX0, shadowY0, shadowZ0,
shadowX1, shadowY1, shadowZ1,
sx0, sy0, sz0, 0.);
side2 = Segment3afp.computeSideLinePoint(
shadowX0, shadowY0, shadowZ0,
shadowX1, shadowY1, shadowZ1,
sx1, sy1, sz1, 0.);
} else {
side1 = Segment3afp.computeSideLinePoint(
shadowX1, shadowY1, shadowZ1,
shadowX0, shadowY0, shadowZ0,
sx0, sy0, sz0, 0.);
side2 = Segment3afp.computeSideLinePoint(
shadowX1, shadowY1, shadowZ1,
shadowX0, shadowY0, shadowZ0,
sx1, sy1, sz1, 0.);
}
if (side1 > 0 || side2 > 0) {
final double x0;
final double x1;
if (shadowYmin == shadowY0) {
x0 = shadowX0;
x1 = shadowX1;
} else {
x0 = shadowX1;
x1 = shadowX0;
}
crossSegmentShadowLine(
x0, shadowYmin,
sx0, sy0, sx1, sy1);
crossSegmentShadowLine(
x1, shadowYmax,
sx0, sy0, sx1, sy1);
}
}
}
/** Determine where the segment is crossing the shadow line.
*
* @param shadowx x coordinate of the reference point of the shadow line.
* @param shadowy y coordinate of the reference point of the shadow line.
* @param sx0 x coordinate of the first point of the segment.
* @param sy0 y coordinate of the first point of the segment.
* @param sx1 x coordinate of the second point of the segment.
* @param sy1 y coordinate of the second point of the segment.
*/
private void crossSegmentShadowLine(
double shadowx, double shadowy,
double sx0, double sy0,
double sx1, double sy1) {
if (shadowy < sy0 && shadowy < sy1) {
// Segment is entirely at the top of shadow line
return;
}
if (shadowy > sy0 && shadowy > sy1) {
// Segment is entirely at the bottom of the shadow line
return;
}
if (shadowx > sx0 && shadowx > sx1) {
// Segment is entirely at the left of the shadow line
return;
}
// Compute the intersection point between the segment and the shadow line
final double xintercept = sx0 + (shadowy - sy0) * (sx1 - sx0) / (sy1 - sy0);
if (shadowx > xintercept) {
// The intersection point is on the left of the shadow line.
return;
}
setCrossingCoordinateForYMax(xintercept, shadowy);
setCrossingCoordinateForYMin(xintercept, shadowy);
if (sy0 < sy1) {
++this.crossings;
} else {
--this.crossings;
}
}
/** Replies the closest point on the shape that is compared to the shadow.
*
* @return the closest point.
*/
public Point3D<?, ?> getClosestPointInOtherShape() {
return this.otherShapeClosestPoint;
}
/** Replies the closest point on the shape that is compared to the shadow.
*
* @return the closest point.
*/
public Point3D<?, ?> getClosestPointInShadowShape() {
return this.shadowShapeClosestPoint;
}
}