/*
* $Id$
* 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.ai;
import org.arakhne.afc.math.MathConstants;
import org.arakhne.afc.math.geometry.PathElementType;
import org.arakhne.afc.math.geometry.PathWindingRule;
import org.arakhne.afc.math.geometry.d2.ai.Segment2ai;
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 BasicPathShadow3ai {
private final PathIterator3ai<?> pathIterator;
private final int boundingMinX;
private final int boundingMinY;
private final int boundingMinZ;
private final int boundingMaxX;
private final int boundingMaxY;
private final int boundingMaxZ;
private boolean started;
private int crossings;
private boolean hasX4ymin;
private boolean hasX4ymax;
private int x4ymin;
private int x4ymax;
/** Construct new path shadow.
* @param path the path that is constituting the shadow.
*/
BasicPathShadow3ai(Path3ai<?, ?, ?, ?, ?, ?> path) {
assert path != null : AssertMessages.notNullParameter();
this.pathIterator = path.getPathIterator();
final RectangularPrism3ai<?, ?, ?, ?, ?, ?> box = path.toBoundingBox();
this.boundingMinX = box.getMinX();
this.boundingMinY = box.getMinY();
this.boundingMinZ = box.getMinZ();
this.boundingMaxX = box.getMaxX();
this.boundingMaxY = box.getMaxY();
this.boundingMaxZ = box.getMaxZ();
}
/** Construct new path shadow.
* @param pathIterator the iterator on the path that is constituting the shadow.
* @param bounds the bounding box enclosing the primitives of the path iterator.
*/
BasicPathShadow3ai(PathIterator3ai<?> pathIterator, RectangularPrism3ai<?, ?, ?, ?, ?, ?> 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.boundingMinZ = bounds.getMinZ();
this.boundingMaxX = bounds.getMaxX();
this.boundingMaxY = bounds.getMaxY();
this.boundingMaxZ = bounds.getMaxZ();
}
/** Construct new path shadow.
* @param pathIterator the iterator on the path that is constituting the shadow.
* @param minX minimum x coordinate of the bounding box enclosing the primitives of the path iterator.
* @param minY minimum y coordinate of the bounding box enclosing the primitives of the path iterator.
* @param minZ minimum z coordinate of the bounding box enclosing the primitives of the path iterator.
* @param maxX maximum x coordinate of the bounding box enclosing the primitives of the path iterator.
* @param maxY maximum y coordinate of the bounding box enclosing the primitives of the path iterator.
* @param maxZ maximum z coordinate of the bounding box enclosing the primitives of the path iterator.
*/
@SuppressWarnings("checkstyle:magicnumber")
BasicPathShadow3ai(PathIterator3ai<?> pathIterator, int minX, int minY, int minZ, int maxX, int maxY, int maxZ) {
assert pathIterator != null : AssertMessages.notNullParameter(0);
assert minX <= maxX : AssertMessages.lowerEqualParameters(1, minX, 4, maxX);
assert minY <= maxY : AssertMessages.lowerEqualParameters(2, minY, 5, maxY);
assert minZ <= maxZ : AssertMessages.lowerEqualParameters(3, minY, 6, maxY);
this.pathIterator = pathIterator;
this.boundingMinX = minX;
this.boundingMinY = minY;
this.boundingMinZ = minZ;
this.boundingMaxX = maxX;
this.boundingMaxY = maxY;
this.boundingMaxZ = maxZ;
}
/** 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}.
*/
public int computeCrossings(
int crossings,
int x0, int y0, int z0,
int x1, int y1, int z1) {
int numCrosses =
Segment3ai.computeCrossingsFromRect(crossings,
this.boundingMinX,
this.boundingMinY,
this.boundingMinZ,
this.boundingMaxX,
this.boundingMaxY,
this.boundingMaxZ,
x0, y0, z0,
x1, y1, z1);
if (numCrosses == MathConstants.SHAPE_INTERSECTS) {
// The segment is intersecting the bounds of the shadow path.
// We must consider the shape of shadow path now.
this.crossings = 0;
this.hasX4ymin = false;
this.hasX4ymax = false;
this.x4ymin = this.boundingMinX;
this.x4ymax = this.boundingMinX;
final PathIterator3ai<?> 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.
final int mask = iterator.getWindingRule() == PathWindingRule.NON_ZERO ? -1 : 2;
if (this.crossings == MathConstants.SHAPE_INTERSECTS
|| (this.crossings & mask) != 0) {
// The given line is intersecting the path shape
return MathConstants.SHAPE_INTERSECTS;
}
// There is no intersection with the shadow path's shape.
int inc = 0;
if (this.hasX4ymin) {
++inc;
}
if (this.hasX4ymax) {
++inc;
}
if (y0 < y1) {
numCrosses = inc;
} else {
numCrosses = -inc;
}
// Apply the previously computed crossings
numCrosses += crossings;
}
return numCrosses;
}
@SuppressWarnings({"checkstyle:parameternumber", "checkstyle:cyclomaticcomplexity",
"checkstyle:npathcomplexity"})
private void discretizePathIterator(
PathIterator3ai<?> pi,
int x1, int y1, int z1, int x2, int y2, int z2) {
if (!pi.hasNext() || this.crossings == MathConstants.SHAPE_INTERSECTS) {
return;
}
PathElement3ai element;
element = pi.next();
if (element.getType() != PathElementType.MOVE_TO) {
throw new IllegalArgumentException(Locale.getString(Path3ai.class, "E1")); //$NON-NLS-1$
}
Path3ai<?, ?, ?, ?, ?, ?> localPath;
int movx = element.getToX();
int movy = element.getToY();
int movz = element.getToZ();
int curx = movx;
int cury = movy;
int curz = movz;
int endx;
int endy;
int endz;
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();
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) {
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;
final boolean isOpen = (curx != movx) || (cury != movy) || (curz != movz);
if (isOpen) {
// Assume that when is the path is open, only
// SHAPE_INTERSECTS may be return
this.crossings = 0;
}
}
private void setCrossingCoordinateForYMax(int x, int y) {
if (y >= this.boundingMaxY && x > this.x4ymax) {
this.x4ymax = x;
this.hasX4ymax = true;
}
}
private void setCrossingCoordinateForYMin(int x, int y) {
if (y <= this.boundingMinY && 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 shadowZ0 z 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 shadowZ1 z 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 sz0 z 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.
* @param sz1 z coordinate of the second point of the segment.
*/
@SuppressWarnings({"checkstyle:parameternumber", "checkstyle:cyclomaticcomplexity",
"checkstyle:npathcomplexity"})
private void crossSegmentTwoShadowLines(
int shadowX0, int shadowY0, int shadowZ0,
int shadowX1, int shadowY1, int shadowZ1,
int sx0, int sy0, int sz0,
int sx1, int sy1, int sz1) {
// Update the global bounds of the shadow.
final int shadowXmin = Math.min(shadowX0, shadowX1);
final int shadowXmax = Math.max(shadowX0, shadowX1);
final int shadowYmin = Math.min(shadowY0, shadowY1);
final int 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
if (sy1 != sy0) {
final double alpha = (sx1 - sx0) / (sy1 - sy0);
if (sy0 < sy1) {
if (sy0 <= shadowYmin) {
final int xintercept = (int) Math.round(sx0 + (shadowYmin - sy0) * alpha);
setCrossingCoordinateForYMin(xintercept, shadowYmin);
++this.crossings;
}
if (sy1 >= shadowYmax) {
final int xintercept = (int) Math.round(sx0 + (shadowYmax - sy0) * alpha);
setCrossingCoordinateForYMax(xintercept, shadowYmax);
++this.crossings;
}
} else {
if (sy1 <= shadowYmin) {
final int xintercept = (int) Math.round(sx0 + (shadowYmin - sy0) * alpha);
setCrossingCoordinateForYMin(xintercept, shadowYmin);
--this.crossings;
}
if (sy0 >= shadowYmax) {
final int xintercept = (int) Math.round(sx0 + (shadowYmax - sy0) * alpha);
setCrossingCoordinateForYMax(xintercept, shadowYmax);
--this.crossings;
}
}
}
} else if (Segment2ai.intersectsSegmentSegment(
shadowX0, shadowY0, shadowX1, shadowY1,
sx0, sy0, sx1, sy1)) {
// The segment is intersecting the shadowed segment.
this.crossings = MathConstants.SHAPE_INTERSECTS;
} else {
final int side1;
final int side2;
final boolean isUp = shadowY0 <= shadowY1;
if (isUp) {
side1 = Segment2ai.findsSideLinePoint(
shadowX0, shadowY0,
shadowX1, shadowY1,
sx0, sy0);
side2 = Segment2ai.findsSideLinePoint(
shadowX0, shadowY0,
shadowX1, shadowY1,
sx1, sy1);
} else {
side1 = Segment2ai.findsSideLinePoint(
shadowX1, shadowY1,
shadowX0, shadowY0,
sx0, sy0);
side2 = Segment2ai.findsSideLinePoint(
shadowX1, shadowY1,
shadowX0, shadowY0,
sx1, sy1);
}
if (side1 > 0 || side2 > 0) {
final int x0;
final int x1;
if (shadowY0 <= shadowY1) {
x0 = shadowX0;
x1 = shadowX1;
} else {
x0 = shadowX1;
x1 = shadowX0;
}
crossSegmentShadowLine(
x1, shadowYmax,
sx0, sy0, sx1, sy1,
isUp);
crossSegmentShadowLine(
x0, shadowYmin,
sx0, sy0, sx1, sy1,
!isUp);
}
}
}
/** 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.
* @param isMax <code>true</code> if the shadow line is for ymax; <code>false</code> if it is for
* ymin.
* @param data the data to update.
*/
private void crossSegmentShadowLine(
int shadowx, int shadowy,
int sx0, int sy0,
int sx1, int sy1,
boolean isMax) {
if (shadowy < sy0 && shadowy < sy1) {
// Segment is entirely at the top of the 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 int xintercept = (int) Math.round((double) sx0 + (shadowy - sy0) * (sx1 - sx0) / (sy1 - sy0));
if (shadowx > xintercept) {
// The intersection point is on the left of the shadow line.
return;
}
if (isMax) {
setCrossingCoordinateForYMax(xintercept, shadowy);
} else {
setCrossingCoordinateForYMin(xintercept, shadowy);
}
if (sy0 < sy1) {
++this.crossings;
} else {
--this.crossings;
}
}
}