org.geotoolkit.display.shape.TransformedShape Maven / Gradle / Ivy
/*
* Geotoolkit.org - An Open Source Java GIS Toolkit
* http://www.geotoolkit.org
*
* (C) 2003-2012, Open Source Geospatial Foundation (OSGeo)
* (C) 2009-2012, Geomatys
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation;
* version 2.1 of the License.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*/
package org.geotoolkit.display.shape;
import java.awt.Shape;
import java.awt.Rectangle;
import java.awt.geom.Point2D;
import java.awt.geom.Rectangle2D;
import java.awt.geom.PathIterator;
import java.awt.geom.AffineTransform;
import java.awt.geom.NoninvertibleTransformException;
import java.io.IOException;
import java.io.ObjectInputStream;
import net.jcip.annotations.NotThreadSafe;
import org.geotoolkit.util.Utilities;
import org.geotoolkit.util.logging.Logging;
import org.geotoolkit.referencing.operation.matrix.XAffineTransform;
import static org.geotoolkit.util.ArgumentChecks.ensureNonNull;
/**
* Applies an arbitrary {@link AffineTransform} on a {@link Shape}. A {@code TransformedShape}
* instance is a view over a shape, i.e. the shape coordinates are transformed on the
* fly, never copied.
*
* The shape to be transformed is specified by {@link #setOriginalShape(Shape)}. The transform
* to apply is specified by the inherited {@code AffineTransform}, which can be modified at any
* time using all its usual methods. Every changes to the original shape or to the inherited
* transform take immediate effect since this class is only a view.
*
* {@note This class is final because extending directly AffineTransform is not a
* good example of object-oriented programming, since a transformed shape is not a special
* kind of affine transform. We did that as a convenience for allowing frequent modifications
* of the transform by direct access to the AffineTransform methods, but this is
* not an example that shoud be replicated.}
*
* {@section Performance cost}
* When {@linkplain #getPathIterator(AffineTransform) iterating over the shape boundary}, the only
* performance cost is a {@linkplain #concatenate(AffineTransform) matrix multiplication} applied
* before the iterator is created - the cost of the iteration itself usually stay
* unchanged.
*
* {@section Example}
* The {@link Arrow2D} class is unconditionally oriented toward 0° arithmetic.
* In order to draw a field of arrows in arbitrary directions, the code below can be used:
*
* {@preformat java
* protected void paint(Graphics2D graphics) {
* Arrow2D arrow = new Arrow2D(...);
* TransformedShape orientedArrow = new TransformedShape(arrow);
* for (int i=0; ireal world" units.
*
* @author Martin Desruisseaux (IRD, Geomatys)
* @version 3.20
*
* @see ProjectedShape
*
* @since 2.0
* @module
*/
@NotThreadSafe
public final class TransformedShape extends AffineTransform implements Shape {
/**
* For cross-version compatibility.
*/
private static final long serialVersionUID = 3541606381365714951L;
/**
* The original shape for which this {@code TransformedShape} is a view.
*/
private Shape shape;
/**
* A temporary point.
*/
private transient Point2D.Double point;
/**
* A temporary rectangle.
*/
private transient Rectangle2D.Double rectangle;
/**
* Constructs a {@code TransformedShape} initialized to the identity transform
* with no original shape. The {@link #setOriginalShape(Shape)} method must be
* invoked at least once before this object can be used.
*/
public TransformedShape() {
initTransientFields();
}
/**
* Constructs a {@code TransformedShape} initialized to the given transform with no
* original shape. The {@link #setOriginalShape(Shape)} method must be invoked at
* least once before this object can be used.
*
* @param transform The initial affine transform.
*/
public TransformedShape(final AffineTransform transform) {
super(transform);
initTransientFields();
}
/**
* Constructs a view of the given shape initialized to the identity transform.
*
* @param shape The shape to wrap in the new {@code TransformedShape} instance.
*/
public TransformedShape(final Shape shape) {
ensureNonNull("shape", shape);
this.shape = shape;
initTransientFields();
}
/**
* Constructs a {@code TransformedShape} initialized to the given transform and shape.
*
* @param shape The shape to wrap in the new {@code TransformedShape} instance.
* @param transform The initial affine transform.
*
* @since 3.20
*/
public TransformedShape(final Shape shape, final AffineTransform transform) {
super(transform);
ensureNonNull("shape", shape);
this.shape = shape;
initTransientFields();
}
/**
* Initializes the transient fields. Invoked on construction and on deserialization.
*/
private void initTransientFields() {
point = new Point2D.Double();
rectangle = new Rectangle2D.Double();
}
/**
* Returns the original shape for which this {@code TransformedShape} is a view.
*
* @return The shape wrapped by this {@code TransformedShape} instance.
*/
public Shape getOriginalShape() {
return shape;
}
/**
* Sets the shape for which this {@code TransformedShape} will be a view.
*
* @param shape The shape to wrap in this {@code TransformedShape} instance.
*/
public void setOriginalShape(final Shape shape) {
ensureNonNull("shape", shape);
this.shape = shape;
}
/**
* Returns the 6 coefficients values as {@code float} numbers. The coefficients are stored
* in the same order than {@link #getMatrix(double[])}, with the first coefficient stored
* in {@code matrix[offset]} and the last coefficient stored in {@code matrix[offset+5]}
*
* @param matrix The matrix where to store the coefficient values.
* @param offset Index of the first element where to write in the {@code matrix} array.
*/
public void getMatrix(final float[] matrix, int offset) {
matrix[ offset] = (float) getScaleX(); // m00
matrix[++offset] = (float) getShearY(); // m10
matrix[++offset] = (float) getShearX(); // m01
matrix[++offset] = (float) getScaleY(); // m11
matrix[++offset] = (float) getTranslateX(); // m02
matrix[++offset] = (float) getTranslateY(); // m12
}
/**
* Sets the transform from a flat matrix. The coefficients are read in the same order
* than they were stored by {@link #getMatrix}.
*
* @param matrix The flat matrix.
* @param offset Index of the first element to use in {@code matrix} array.
*/
public void setTransform(final float[] matrix, int offset) {
setTransform(matrix[ offset], matrix[++offset], matrix[++offset],
matrix[++offset], matrix[++offset], matrix[++offset]);
}
/**
* Tests if the specified coordinate is inside the boundary of this shape.
* This method might conservatively return {@code false} if the transform is not invertible.
*
* The default implementation delegates to {@link #contains(Point2D)}.
*
* @param x The x ordinate of the point to be tested.
* @param y The y ordinate of the point to be tested.
* @return {@code true} if this shape contains the given point.
*/
@Override
public boolean contains(final double x, final double y) {
final Point2D.Double p = point;
p.x = x;
p.y = y;
return contains(p);
}
/**
* Tests if a specified {@link Point2D} is inside the boundary of this shape.
* This method might conservatively return {@code false} if the transform is not invertible.
*
* @param p The point to be tested.
* @return {@code true} if this shape contains the given point.
*/
@Override
public boolean contains(final Point2D p) {
try {
return shape.contains(inverseTransform(p, point));
} catch (NoninvertibleTransformException exception) {
Logging.recoverableException(TransformedShape.class, "contains", exception);
return false;
}
}
/**
* Tests if the interior of this shape entirely contains the specified rectangular area.
* This method might conservatively return {@code false} if the transform is not invertible
* or if the calculation of {@code originalShape.contains(...)} is too expensive.
*
* The default implementation delegates to {@link #contains(Rectangle2D)}.
*
* @param x The minimal x ordinate of the rectangle to be tested.
* @param y The minimal y ordinate of the rectangle to be tested.
* @param width The width of the rectangle to be tested.
* @param height The height of the rectangle to be tested.
* @return {@code true} if this shape contains the given rectangle.
*/
@Override
public boolean contains(final double x, final double y, final double width, final double height) {
final Rectangle2D.Double r = rectangle;
r.x = x;
r.y = y;
r.width = width;
r.height = height;
return contains(r);
}
/**
* Tests if the interior of this shape entirely contains the specified rectangle.
* This method might conservatively return {@code false} if the transform is not
* invertible or if the calculation of {@code originalShape.contains(...)} is too
* expensive.
*
* @param r The rectangle to be tested.
* @return {@code true} if this shape contains the given rectangle.
*/
@Override
public boolean contains(final Rectangle2D r) {
try {
return shape.contains(XAffineTransform.inverseTransform(this, r, rectangle));
} catch (NoninvertibleTransformException exception) {
Logging.recoverableException(TransformedShape.class, "contains", exception);
return false; // Consistent with the Shape interface contract.
}
}
/**
* Tests if the interior of this shape intersects the interior of a specified rectangular area.
* This method might conservatively return {@code true} if the transform is not invertible or
* if the calculation of {@code originalShape.intersects(...)} is too expensive.
*
* The default implementation delegates to {@link #intersects(Rectangle2D)}.
*
* @param x The minimal x ordinate of the rectangle to be tested.
* @param y The minimal y ordinate of the rectangle to be tested.
* @param width The width of the rectangle to be tested.
* @param height The height of the rectangle to be tested.
* @return {@code true} if this shape intersects the given rectangle.
*/
@Override
public boolean intersects(double x, double y, double width, double height) {
final Rectangle2D.Double r = rectangle;
r.x = x;
r.y = y;
r.width = width;
r.height = height;
return intersects(r);
}
/**
* Tests if the interior of this shape intersects the interior of a specified rectangle.
* This method might conservatively return {@code true} if the transform is not invertible
* or if the calculation of {@code originalShape.intersects(...)} is too expensive.
*
* @param r The rectangle to be tested.
* @return {@code true} if this shape intersects the given rectangle.
*/
@Override
public boolean intersects(final Rectangle2D r) {
try {
return shape.intersects(XAffineTransform.inverseTransform(this, r, rectangle));
} catch (NoninvertibleTransformException exception) {
Logging.recoverableException(TransformedShape.class, "intersects", exception);
return true; // Consistent with the Shape interface contract.
}
}
/**
* Returns an integer rectangle that completely encloses this shape.
*/
@Override
public Rectangle getBounds() {
// Delegates to getBounds2D(), not getBounds(), because a scale greater than 1
// will use the fraction digits of a number that would be otherwise rounded.
return (Rectangle) XAffineTransform.transform(this, shape.getBounds2D(), new Rectangle());
}
/**
* Returns a high precision and more accurate bounding box of the
* shape than the {@link #getBounds} method.
*/
@Override
public Rectangle2D getBounds2D() {
return XAffineTransform.transform(this, shape.getBounds2D(), null);
}
/**
* Returns an iterator object that iterates along the shape boundary
* and provides access to the geometry of the shape outline.
*/
@Override
public PathIterator getPathIterator(AffineTransform at) {
if (!isIdentity()) {
if (at == null || at.isIdentity()) {
return shape.getPathIterator(this);
}
at = new AffineTransform(at);
at.concatenate(this);
}
return shape.getPathIterator(at);
}
/**
* Returns an iterator object that iterates along the shape boundary and provides
* access to a flattened view of the shape outline geometry.
*/
@Override
public PathIterator getPathIterator(AffineTransform at, final double flatness) {
if (!isIdentity()) {
if (at == null || at.isIdentity()) {
return shape.getPathIterator(this, flatness);
}
at = new AffineTransform(at);
at.concatenate(this);
}
return shape.getPathIterator(at, flatness);
}
/**
* Returns a hash code value for this shape.
*
* @since 3.20
*/
@Override
public int hashCode() {
int code = super.hashCode() ^ (int) serialVersionUID;
if (shape != null) {
code ^= shape.hashCode();
}
return code;
}
/**
* Compares this shape with the given object for equality. Do not compare
* {@code TransformedShape} instances with plain {@link AffineTransform} instances,
* because the "be symmetric" part of the {@link Object#equals(Object)} contract
* can not be enforced.
*
* @param object The object to compare with this shape.
*
* @since 3.20
*/
@Override
public boolean equals(final Object object) {
if (object instanceof TransformedShape && super.equals(object)) {
return Utilities.equals(shape, ((TransformedShape) object).shape);
}
return false;
}
/**
* Invoked on deserialization.
*/
private void readObject(final ObjectInputStream in) throws IOException, ClassNotFoundException {
in.readObject();
initTransientFields();
}
}