下面列出了java.awt.geom.Line2D#getY2 ( ) 实例代码，或者点击链接到github查看源代码，也可以在右侧发表评论。
/**
* Creates a new line by extending an existing line.
*
* @param line the line (<code>null</code> not permitted).
* @param startPercent the amount to extend the line at the start point
* end.
* @param endPercent the amount to extend the line at the end point end.
*
* @return A new line.
*/
private Line2D extendLine(Line2D line, double startPercent,
double endPercent) {
if (line == null) {
throw new IllegalArgumentException("Null 'line' argument.");
}
double x1 = line.getX1();
double x2 = line.getX2();
double deltaX = x2 - x1;
double y1 = line.getY1();
double y2 = line.getY2();
double deltaY = y2 - y1;
x1 = x1 - (startPercent * deltaX);
y1 = y1 - (startPercent * deltaY);
x2 = x2 + (endPercent * deltaX);
y2 = y2 + (endPercent * deltaY);
return new Line2D.Double(x1, y1, x2, y2);
}
/**
* Creates a new line by extending an existing line.
*
* @param line the line (<code>null</code> not permitted).
* @param startPercent the amount to extend the line at the start point
* end.
* @param endPercent the amount to extend the line at the end point end.
*
* @return A new line.
*
* @since 1.0.18
*/
public static Line2D extendLine(Line2D line, double startPercent,
double endPercent) {
ParamChecks.nullNotPermitted(line, "line");
double x1 = line.getX1();
double x2 = line.getX2();
double deltaX = x2 - x1;
double y1 = line.getY1();
double y2 = line.getY2();
double deltaY = y2 - y1;
x1 = x1 - (startPercent * deltaX);
y1 = y1 - (startPercent * deltaY);
x2 = x2 + (endPercent * deltaX);
y2 = y2 + (endPercent * deltaY);
return new Line2D.Double(x1, y1, x2, y2);
}
/**
* Return the bisector (french: médiatrice) of the provided segment
*
* @param segment the provided segment
* @return (a segment on) the bisector
*/
public static Line2D bisector (Line2D segment)
{
double x1 = segment.getX1();
double y1 = segment.getY1();
double hdx = (segment.getX2() - x1) / 2;
double hdy = (segment.getY2() - y1) / 2;
// Use middle as reference point
double mx = x1 + hdx;
double my = y1 + hdy;
double x3 = mx + hdy;
double y3 = my - hdx;
double x4 = mx - hdy;
double y4 = my + hdx;
return new Line2D.Double(x3, y3, x4, y4);
}
/**
* Create a thin (1 mm wide) rectangle path representing a line.
*
* @param line the line.
* @return rectangle path for the line.
*/
private static Path2D createLinePath(Line2D line) {
// Make rectangle width 1mm.
double width = .001D;
double length = line.getP1().distance(line.getP2());
double centerX = (line.getX1() + line.getX2()) / 2D;
double centerY = (line.getY1() + line.getY2()) / 2D;
double x1 = centerX - (width / 2D);
double y1 = centerY - (length / 2D);
Rectangle2D lineRect = new Rectangle2D.Double(x1, y1, width, length);
double facing = getDirection(line.getP1(), line.getP2());
Path2D rectPath = getPathFromRectangleRotation(lineRect, facing);
return rectPath;
}
/**
* This method calculates intersections of two lines.
*
* @param a
* Line 1
* @param b
* Line 2
* @return Intersection point
*/
private static Point getLinesIntersection(Line2D a, Line2D b) {
double d = (a.getX1() - a.getX2()) * (b.getY2() - b.getY1()) - (a.getY1() - a.getY2()) * (b.getX2() - b.getX1());
double da = (a.getX1() - b.getX1()) * (b.getY2() - b.getY1()) - (a.getY1() - b.getY1()) * (b.getX2() - b.getX1());
// double db = (a.getX1()-a.getX2())*(a.getY1()-b.getY1()) - (a.getY1()-a.getY2())*(a.getX1()-b.getX1());
double ta = da / d;
// double tb = db/d;
Point p = new Point();
p.setLocation(a.getX1() + ta * (a.getX2() - a.getX1()), a.getY1() + ta * (a.getY2() - a.getY1()));
return p;
}
@Override
public Point2D getEndVector (boolean reverse)
{
int dir = reverse ? (-1) : 1;
Line2D l = line.toDouble();
double length = l.getP1().distance(l.getP2());
return new Point2D.Double(
(dir * (l.getX2() - l.getX1())) / length,
(dir * (l.getY2() - l.getY1())) / length);
}
@Override
public void visit (HeadInter head)
{
final Line2D midLine = head.getMidLine();
if (midLine != null) {
if (splitMirrors()) {
// Draw head proper half
int width = head.getBounds().width;
int xDir = midLine.getY2() > midLine.getY1() ? -1 : +1;
Path2D p = new Path2D.Double();
p.append(midLine, false);
p.lineTo(midLine.getX2() + xDir * width, midLine.getY2());
p.lineTo(midLine.getX1() + xDir * width, midLine.getY1());
p.closePath();
java.awt.Shape oldClip = g.getClip();
g.clip(p);
visit((Inter) head);
g.setClip(oldClip);
} else {
visit((Inter) head);
}
// Draw midLine using complementary color of head
Color compColor = UIUtil.complementaryColor(g.getColor());
Stroke oldStroke = UIUtil.setAbsoluteStroke(g, 1f);
g.setColor(compColor);
g.draw(midLine);
g.setStroke(oldStroke);
} else {
visit((Inter) head);
}
}
/**
* Report the middle point of a Line2D.
*
* @param line provided line2D
* @return the middle point between p1 and p2
*/
public static Point2D middle (Line2D line)
{
return new Point2D.Double(
(line.getX1() + line.getX2()) / 2.0,
(line.getY1() + line.getY2()) / 2.0);
}
/**
* Computation of rotation from first to last point, with middle as approximate
* middle point of the curve.
*
* @param line straight line from curve start to curve stop
* @param middle middle point of curve
* @return central rotation angle (in radians) from curve start to curve stop.
*/
public static double rotation (Line2D line,
Point2D middle)
{
double dx = line.getX2() - line.getX1();
double dy = line.getY2() - line.getY1();
double halfChordLengthSq = ((dx * dx) + (dy * dy)) / 4;
double sagittaSq = line.ptLineDistSq(middle);
return 4 * Math.atan(Math.sqrt(sagittaSq / halfChordLengthSq));
}
/**
* Creates a region surrounding a line segment by 'widening' the line
* segment. A typical use for this method is the creation of a
* 'clickable' region for a line that is displayed on-screen.
*
* @param line the line (<code>null</code> not permitted).
* @param width the width of the region.
*
* @return A region that surrounds the line.
*/
public static Shape createLineRegion(Line2D line, float width) {
GeneralPath result = new GeneralPath();
float x1 = (float) line.getX1();
float x2 = (float) line.getX2();
float y1 = (float) line.getY1();
float y2 = (float) line.getY2();
if ((x2 - x1) != 0.0) {
double theta = Math.atan((y2 - y1) / (x2 - x1));
float dx = (float) Math.sin(theta) * width;
float dy = (float) Math.cos(theta) * width;
result.moveTo(x1 - dx, y1 + dy);
result.lineTo(x1 + dx, y1 - dy);
result.lineTo(x2 + dx, y2 - dy);
result.lineTo(x2 - dx, y2 + dy);
result.closePath();
}
else {
// special case, vertical line
result.moveTo(x1 - width / 2.0f, y1);
result.lineTo(x1 + width / 2.0f, y1);
result.lineTo(x2 + width / 2.0f, y2);
result.lineTo(x2 - width / 2.0f, y2);
result.closePath();
}
return result;
}
/**
* Clips the specified line to the given rectangle.
*
* @param line the line (<code>null</code> not permitted).
* @param rect the clipping rectangle (<code>null</code> not permitted).
*
* @return <code>true</code> if the clipped line is visible, and
* <code>false</code> otherwise.
*/
public static boolean clipLine(Line2D line, Rectangle2D rect) {
double x1 = line.getX1();
double y1 = line.getY1();
double x2 = line.getX2();
double y2 = line.getY2();
double minX = rect.getMinX();
double maxX = rect.getMaxX();
double minY = rect.getMinY();
double maxY = rect.getMaxY();
int f1 = rect.outcode(x1, y1);
int f2 = rect.outcode(x2, y2);
while ((f1 | f2) != 0) {
if ((f1 & f2) != 0) {
return false;
}
double dx = (x2 - x1);
double dy = (y2 - y1);
// update (x1, y1), (x2, y2) and f1 and f2 using intersections
// then recheck
if (f1 != 0) {
// first point is outside, so we update it against one of the
// four sides then continue
if ((f1 & Rectangle2D.OUT_LEFT) == Rectangle2D.OUT_LEFT
&& dx != 0.0) {
y1 = y1 + (minX - x1) * dy / dx;
x1 = minX;
}
else if ((f1 & Rectangle2D.OUT_RIGHT) == Rectangle2D.OUT_RIGHT
&& dx != 0.0) {
y1 = y1 + (maxX - x1) * dy / dx;
x1 = maxX;
}
else if ((f1 & Rectangle2D.OUT_BOTTOM) == Rectangle2D.OUT_BOTTOM
&& dy != 0.0) {
x1 = x1 + (maxY - y1) * dx / dy;
y1 = maxY;
}
else if ((f1 & Rectangle2D.OUT_TOP) == Rectangle2D.OUT_TOP
&& dy != 0.0) {
x1 = x1 + (minY - y1) * dx / dy;
y1 = minY;
}
f1 = rect.outcode(x1, y1);
}
else if (f2 != 0) {
// second point is outside, so we update it against one of the
// four sides then continue
if ((f2 & Rectangle2D.OUT_LEFT) == Rectangle2D.OUT_LEFT
&& dx != 0.0) {
y2 = y2 + (minX - x2) * dy / dx;
x2 = minX;
}
else if ((f2 & Rectangle2D.OUT_RIGHT) == Rectangle2D.OUT_RIGHT
&& dx != 0.0) {
y2 = y2 + (maxX - x2) * dy / dx;
x2 = maxX;
}
else if ((f2 & Rectangle2D.OUT_BOTTOM) == Rectangle2D.OUT_BOTTOM
&& dy != 0.0) {
x2 = x2 + (maxY - y2) * dx / dy;
y2 = maxY;
}
else if ((f2 & Rectangle2D.OUT_TOP) == Rectangle2D.OUT_TOP
&& dy != 0.0) {
x2 = x2 + (minY - y2) * dx / dy;
y2 = minY;
}
f2 = rect.outcode(x2, y2);
}
}
line.setLine(x1, y1, x2, y2);
return true; // the line is visible - if it wasn't, we'd have
// returned false from within the while loop above
}
/**
* Calculates the anchor point for a label.
*
* @param line the line for the crosshair.
* @param anchor the anchor point.
* @param deltaX the x-offset.
* @param deltaY the y-offset.
*
* @return The anchor point.
*/
private Point2D calculateLabelPoint(Line2D line, RectangleAnchor anchor,
double deltaX, double deltaY) {
double x = 0.0;
double y = 0.0;
boolean left = (anchor == RectangleAnchor.BOTTOM_LEFT
|| anchor == RectangleAnchor.LEFT
|| anchor == RectangleAnchor.TOP_LEFT);
boolean right = (anchor == RectangleAnchor.BOTTOM_RIGHT
|| anchor == RectangleAnchor.RIGHT
|| anchor == RectangleAnchor.TOP_RIGHT);
boolean top = (anchor == RectangleAnchor.TOP_LEFT
|| anchor == RectangleAnchor.TOP
|| anchor == RectangleAnchor.TOP_RIGHT);
boolean bottom = (anchor == RectangleAnchor.BOTTOM_LEFT
|| anchor == RectangleAnchor.BOTTOM
|| anchor == RectangleAnchor.BOTTOM_RIGHT);
Rectangle rect = line.getBounds();
// we expect the line to be vertical or horizontal
if (line.getX1() == line.getX2()) { // vertical
x = line.getX1();
y = (line.getY1() + line.getY2()) / 2.0;
if (left) {
x = x - deltaX;
}
if (right) {
x = x + deltaX;
}
if (top) {
y = Math.min(line.getY1(), line.getY2()) + deltaY;
}
if (bottom) {
y = Math.max(line.getY1(), line.getY2()) - deltaY;
}
}
else { // horizontal
x = (line.getX1() + line.getX2()) / 2.0;
y = line.getY1();
if (left) {
x = Math.min(line.getX1(), line.getX2()) + deltaX;
}
if (right) {
x = Math.max(line.getX1(), line.getX2()) - deltaX;
}
if (top) {
y = y - deltaY;
}
if (bottom) {
y = y + deltaY;
}
}
return new Point2D.Double(x, y);
}
/**
* Clips the specified line to the given rectangle.
*
* @param line the line (<code>null</code> not permitted).
* @param rect the clipping rectangle (<code>null</code> not permitted).
*
* @return <code>true</code> if the clipped line is visible, and
* <code>false</code> otherwise.
*/
public static boolean clipLine(Line2D line, Rectangle2D rect) {
double x1 = line.getX1();
double y1 = line.getY1();
double x2 = line.getX2();
double y2 = line.getY2();
double minX = rect.getMinX();
double maxX = rect.getMaxX();
double minY = rect.getMinY();
double maxY = rect.getMaxY();
int f1 = rect.outcode(x1, y1);
int f2 = rect.outcode(x2, y2);
while ((f1 | f2) != 0) {
if ((f1 & f2) != 0) {
return false;
}
double dx = (x2 - x1);
double dy = (y2 - y1);
// update (x1, y1), (x2, y2) and f1 and f2 using intersections
// then recheck
if (f1 != 0) {
// first point is outside, so we update it against one of the
// four sides then continue
if ((f1 & Rectangle2D.OUT_LEFT) == Rectangle2D.OUT_LEFT
&& dx != 0.0) {
y1 = y1 + (minX - x1) * dy / dx;
x1 = minX;
}
else if ((f1 & Rectangle2D.OUT_RIGHT) == Rectangle2D.OUT_RIGHT
&& dx != 0.0) {
y1 = y1 + (maxX - x1) * dy / dx;
x1 = maxX;
}
else if ((f1 & Rectangle2D.OUT_BOTTOM) == Rectangle2D.OUT_BOTTOM
&& dy != 0.0) {
x1 = x1 + (maxY - y1) * dx / dy;
y1 = maxY;
}
else if ((f1 & Rectangle2D.OUT_TOP) == Rectangle2D.OUT_TOP
&& dy != 0.0) {
x1 = x1 + (minY - y1) * dx / dy;
y1 = minY;
}
f1 = rect.outcode(x1, y1);
}
else if (f2 != 0) {
// second point is outside, so we update it against one of the
// four sides then continue
if ((f2 & Rectangle2D.OUT_LEFT) == Rectangle2D.OUT_LEFT
&& dx != 0.0) {
y2 = y2 + (minX - x2) * dy / dx;
x2 = minX;
}
else if ((f2 & Rectangle2D.OUT_RIGHT) == Rectangle2D.OUT_RIGHT
&& dx != 0.0) {
y2 = y2 + (maxX - x2) * dy / dx;
x2 = maxX;
}
else if ((f2 & Rectangle2D.OUT_BOTTOM) == Rectangle2D.OUT_BOTTOM
&& dy != 0.0) {
x2 = x2 + (maxY - y2) * dx / dy;
y2 = maxY;
}
else if ((f2 & Rectangle2D.OUT_TOP) == Rectangle2D.OUT_TOP
&& dy != 0.0) {
x2 = x2 + (minY - y2) * dx / dy;
y2 = minY;
}
f2 = rect.outcode(x2, y2);
}
}
line.setLine(x1, y1, x2, y2);
return true; // the line is visible - if it wasn't, we'd have
// returned false from within the while loop above
}
public static double getShiftByY(Line2D aLine, double aPointDeltaY) {
return aPointDeltaY * ((aLine.getX2() - aLine.getX1()) / (aLine.getY2() - aLine.getY1()));
}
/**
* Returns the intersection point of two lines.
*
* @param line1 First line
* @param line2 Second line
* @return The Point object where the two lines intersect. This method
* returns null if the two lines do not intersect.
* @throws <tt>MultipleIntersectionException</tt> when the two lines
* have more than one intersection point.
*/
static public Point getIntersection(Line2D line1, Line2D line2)
throws Exception {
double dyline1, dxline1;
double dyline2, dxline2, e, f;
double x1line1, y1line1, x2line1, y2line1;
double x1line2, y1line2, x2line2, y2line2;
if (!line1.intersectsLine(line2)) {
return null;
}
/* first, check to see if the segments intersect by parameterization
on s and t; if s and t are both between [0,1], then the
segments intersect */
x1line1 = line1.getX1();
y1line1 = line1.getY1();
x2line1 = line1.getX2();
y2line1 = line1.getY2();
x1line2 = line2.getX1();
y1line2 = line2.getY1();
x2line2 = line2.getX2();
y2line2 = line2.getY2();
/* check to see if the segments have any endpoints in common. If they do,
then return the endpoints as the intersection point */
if ((x1line1 == x1line2) && (y1line1 == y1line2)) {
return (new Point((int) x1line1, (int) y1line1));
}
if ((x1line1 == x2line2) && (y1line1 == y2line2)) {
return (new Point((int) x1line1, (int) y1line1));
}
if ((x2line1 == x1line2) && (y2line1 == y1line2)) {
return (new Point((int) x2line1, (int) y2line1));
}
if ((x2line1 == x2line2) && (y2line1 == y2line2)) {
return (new Point((int) x2line1, (int) y2line1));
}
dyline1 = -(y2line1 - y1line1);
dxline1 = x2line1 - x1line1;
dyline2 = -(y2line2 - y1line2);
dxline2 = x2line2 - x1line2;
e = -(dyline1 * x1line1) - (dxline1 * y1line1);
f = -(dyline2 * x1line2) - (dxline2 * y1line2);
/* compute the intersection point using
ax+by+e = 0 and cx+dy+f = 0
If there is more than 1 intersection point between two lines,
*/
if ((dyline1 * dxline2 - dyline2 * dxline1) == 0) {
throw new Exception("ZERO!");
}
return (new Point(
(int) (-(e * dxline2 - dxline1 * f) / (dyline1 * dxline2 - dyline2 * dxline1)),
(int) (-(dyline1 * f - dyline2 * e) / (dyline1 * dxline2 - dyline2 * dxline1))));
}
/**
* Clips the specified line to the given rectangle.
*
* @param line the line (<code>null</code> not permitted).
* @param rect the clipping rectangle (<code>null</code> not permitted).
*
* @return <code>true</code> if the clipped line is visible, and
* <code>false</code> otherwise.
*
* @since 1.2.0
*/
public static boolean clipLine(Line2D line, Rectangle2D rect) {
double x1 = line.getX1();
double y1 = line.getY1();
double x2 = line.getX2();
double y2 = line.getY2();
double minX = rect.getMinX();
double maxX = rect.getMaxX();
double minY = rect.getMinY();
double maxY = rect.getMaxY();
int f1 = rect.outcode(x1, y1);
int f2 = rect.outcode(x2, y2);
while ((f1 | f2) != 0) {
if ((f1 & f2) != 0) {
return false;
}
double dx = (x2 - x1);
double dy = (y2 - y1);
// update (x1, y1), (x2, y2) and f1 and f2 using intersections
// then recheck
if (f1 != 0) {
// first point is outside, so we update it against one of the
// four sides then continue
if ((f1 & Rectangle2D.OUT_LEFT) == Rectangle2D.OUT_LEFT
&& dx != 0.0) {
y1 = y1 + (minX - x1) * dy / dx;
x1 = minX;
}
else if ((f1 & Rectangle2D.OUT_RIGHT) == Rectangle2D.OUT_RIGHT
&& dx != 0.0) {
y1 = y1 + (maxX - x1) * dy / dx;
x1 = maxX;
}
else if ((f1 & Rectangle2D.OUT_BOTTOM) == Rectangle2D.OUT_BOTTOM
&& dy != 0.0) {
x1 = x1 + (maxY - y1) * dx / dy;
y1 = maxY;
}
else if ((f1 & Rectangle2D.OUT_TOP) == Rectangle2D.OUT_TOP
&& dy != 0.0) {
x1 = x1 + (minY - y1) * dx / dy;
y1 = minY;
}
f1 = rect.outcode(x1, y1);
}
else if (f2 != 0) {
// second point is outside, so we update it against one of the
// four sides then continue
if ((f2 & Rectangle2D.OUT_LEFT) == Rectangle2D.OUT_LEFT
&& dx != 0.0) {
y2 = y2 + (minX - x2) * dy / dx;
x2 = minX;
}
else if ((f2 & Rectangle2D.OUT_RIGHT) == Rectangle2D.OUT_RIGHT
&& dx != 0.0) {
y2 = y2 + (maxX - x2) * dy / dx;
x2 = maxX;
}
else if ((f2 & Rectangle2D.OUT_BOTTOM) == Rectangle2D.OUT_BOTTOM
&& dy != 0.0) {
x2 = x2 + (maxY - y2) * dx / dy;
y2 = maxY;
}
else if ((f2 & Rectangle2D.OUT_TOP) == Rectangle2D.OUT_TOP
&& dy != 0.0) {
x2 = x2 + (minY - y2) * dx / dy;
y2 = minY;
}
f2 = rect.outcode(x2, y2);
}
}
line.setLine(x1, y1, x2, y2);
return true; // the line is visible - if it wasn't, we'd have
// returned false from within the while loop above
}
/**
* Clips the specified line to the given rectangle.
*
* @param line the line (<code>null</code> not permitted).
* @param rect the clipping rectangle (<code>null</code> not permitted).
*
* @return <code>true</code> if the clipped line is visible, and
* <code>false</code> otherwise.
*/
public static boolean clipLine(Line2D line, Rectangle2D rect) {
double x1 = line.getX1();
double y1 = line.getY1();
double x2 = line.getX2();
double y2 = line.getY2();
double minX = rect.getMinX();
double maxX = rect.getMaxX();
double minY = rect.getMinY();
double maxY = rect.getMaxY();
int f1 = rect.outcode(x1, y1);
int f2 = rect.outcode(x2, y2);
while ((f1 | f2) != 0) {
if ((f1 & f2) != 0) {
return false;
}
double dx = (x2 - x1);
double dy = (y2 - y1);
// update (x1, y1), (x2, y2) and f1 and f2 using intersections
// then recheck
if (f1 != 0) {
// first point is outside, so we update it against one of the
// four sides then continue
if ((f1 & Rectangle2D.OUT_LEFT) == Rectangle2D.OUT_LEFT
&& dx != 0.0) {
y1 = y1 + (minX - x1) * dy / dx;
x1 = minX;
}
else if ((f1 & Rectangle2D.OUT_RIGHT) == Rectangle2D.OUT_RIGHT
&& dx != 0.0) {
y1 = y1 + (maxX - x1) * dy / dx;
x1 = maxX;
}
else if ((f1 & Rectangle2D.OUT_BOTTOM) == Rectangle2D.OUT_BOTTOM
&& dy != 0.0) {
x1 = x1 + (maxY - y1) * dx / dy;
y1 = maxY;
}
else if ((f1 & Rectangle2D.OUT_TOP) == Rectangle2D.OUT_TOP
&& dy != 0.0) {
x1 = x1 + (minY - y1) * dx / dy;
y1 = minY;
}
f1 = rect.outcode(x1, y1);
}
else if (f2 != 0) {
// second point is outside, so we update it against one of the
// four sides then continue
if ((f2 & Rectangle2D.OUT_LEFT) == Rectangle2D.OUT_LEFT
&& dx != 0.0) {
y2 = y2 + (minX - x2) * dy / dx;
x2 = minX;
}
else if ((f2 & Rectangle2D.OUT_RIGHT) == Rectangle2D.OUT_RIGHT
&& dx != 0.0) {
y2 = y2 + (maxX - x2) * dy / dx;
x2 = maxX;
}
else if ((f2 & Rectangle2D.OUT_BOTTOM) == Rectangle2D.OUT_BOTTOM
&& dy != 0.0) {
x2 = x2 + (maxY - y2) * dx / dy;
y2 = maxY;
}
else if ((f2 & Rectangle2D.OUT_TOP) == Rectangle2D.OUT_TOP
&& dy != 0.0) {
x2 = x2 + (minY - y2) * dx / dy;
y2 = minY;
}
f2 = rect.outcode(x2, y2);
}
}
line.setLine(x1, y1, x2, y2);
return true; // the line is visible - if it wasn't, we'd have
// returned false from within the while loop above
}
/**
* Calculates the anchor point for a label.
*
* @param line the line for the crosshair.
* @param anchor the anchor point.
* @param deltaX the x-offset.
* @param deltaY the y-offset.
*
* @return The anchor point.
*/
private Point2D calculateLabelPoint(Line2D line, RectangleAnchor anchor,
double deltaX, double deltaY) {
double x, y;
boolean left = (anchor == RectangleAnchor.BOTTOM_LEFT
|| anchor == RectangleAnchor.LEFT
|| anchor == RectangleAnchor.TOP_LEFT);
boolean right = (anchor == RectangleAnchor.BOTTOM_RIGHT
|| anchor == RectangleAnchor.RIGHT
|| anchor == RectangleAnchor.TOP_RIGHT);
boolean top = (anchor == RectangleAnchor.TOP_LEFT
|| anchor == RectangleAnchor.TOP
|| anchor == RectangleAnchor.TOP_RIGHT);
boolean bottom = (anchor == RectangleAnchor.BOTTOM_LEFT
|| anchor == RectangleAnchor.BOTTOM
|| anchor == RectangleAnchor.BOTTOM_RIGHT);
Rectangle rect = line.getBounds();
// we expect the line to be vertical or horizontal
if (line.getX1() == line.getX2()) { // vertical
x = line.getX1();
y = (line.getY1() + line.getY2()) / 2.0;
if (left) {
x = x - deltaX;
}
if (right) {
x = x + deltaX;
}
if (top) {
y = Math.min(line.getY1(), line.getY2()) + deltaY;
}
if (bottom) {
y = Math.max(line.getY1(), line.getY2()) - deltaY;
}
}
else { // horizontal
x = (line.getX1() + line.getX2()) / 2.0;
y = line.getY1();
if (left) {
x = Math.min(line.getX1(), line.getX2()) + deltaX;
}
if (right) {
x = Math.max(line.getX1(), line.getX2()) - deltaX;
}
if (top) {
y = y - deltaY;
}
if (bottom) {
y = y + deltaY;
}
}
return new Point2D.Double(x, y);
}
public static double getShiftByX(Line2D aLine, double aPointDeltaX) {
double width = aLine.getX2() - aLine.getX1();
double height = aLine.getY2() - aLine.getY1();
return aPointDeltaX * (height / width);
}
/**
* Gets the distance and point along a Line2D at a specified y.
* If the Line2D is horizontal this returns null.
*
* Based on a simplification of algorithm described by Paul Burke
* at http://local.wasp.uwa.edu.au/~pbourke/geometry/lineline2d/ (April 1986)
*
* @param line the line
* @param y the value of y
* @return Object[] {fractional distance from line end, Point2D}
*/
private Object[] getDistanceAndPointAtY(Line2D line, double y) {
double dy = line.getY2()-line.getY1();
// if line is horizontal, return null
if (dy==0) return null;
// parametric eqn of line: P = P1 + u(P2 - P1)
double u = (y-line.getY1())/dy;
double x = line.getX1() + u*(line.getX2()-line.getX1());
return new Object[] {u, new Point2D.Double(x, y)};
}