org.eclipse.swt.graphics.Path Maven / Gradle / Ivy

Go to download
Show more of this group Show more artifacts with this name
Show all versions of org.eclipse.swt.gtk.linux.ppc64le Show documentation
Standard Widget Toolkit for GTK on ppc64le
The newest version!
/*******************************************************************************
 * Copyright (c) 2000, 2021 IBM Corporation and others.
 *
 * This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License 2.0
 * which accompanies this distribution, and is available at
 * https://www.eclipse.org/legal/epl-2.0/
 *
 * SPDX-License-Identifier: EPL-2.0
 *
 * Contributors:
 *     IBM Corporation - initial API and implementation
 *******************************************************************************/
package org.eclipse.swt.graphics;

import org.eclipse.swt.*;
import org.eclipse.swt.internal.*;
import org.eclipse.swt.internal.cairo.*;

/**
 * Instances of this class represent paths through the two-dimensional
 * coordinate system. Paths do not have to be continuous, and can be
 * described using lines, rectangles, arcs, cubic or quadratic bezier curves,
 * glyphs, or other paths.
 * 
 * Application code must explicitly invoke the Path.dispose()
 * method to release the operating system resources managed by each instance
 * when those instances are no longer required.
 * 
 * 
 * This class requires the operating system's advanced graphics subsystem
 * which may not be available on some platforms.
 * 
 *
 * @see Path, Pattern snippets
 * @see SWT Example: GraphicsExample
 * @see Sample code and further information
 *
 * @since 3.1
 */
public class Path extends Resource {

	/**
	 * the OS resource for the Path
	 * (Warning: This field is platform dependent)
	 * 
	 * IMPORTANT: This field is not part of the SWT
	 * public API. It is marked public only so that it can be shared
	 * within the packages provided by SWT. It is not available on all
	 * platforms and should never be accessed from application code.
	 * 
	 *
	 * @noreference This field is not intended to be referenced by clients.
	 */
	public long handle;

	boolean moved, closed = true;

/**
 * Constructs a new empty Path.
 * 
 * This operation requires the operating system's advanced
 * graphics subsystem which may not be available on some
 * platforms.
 * 
 * 
 * You must dispose the path when it is no longer required.
 * 
 *
 * @param device the device on which to allocate the path
 *
 * @exception IllegalArgumentException 
 *    ERROR_NULL_ARGUMENT - if the device is null and there is no current device
 * 
 * @exception SWTException 
 *    ERROR_NO_GRAPHICS_LIBRARY - if advanced graphics are not available
 * 
 * @exception SWTError 
 *    ERROR_NO_HANDLES if a handle for the path could not be obtained
 * 
 *
 * @see #dispose()
 */
public Path (Device device) {
	super(device);
	long surface = Cairo.cairo_image_surface_create(Cairo.CAIRO_FORMAT_ARGB32, 1, 1);
	if (surface == 0) SWT.error(SWT.ERROR_NO_HANDLES);
	handle = Cairo.cairo_create(surface);
	Cairo.cairo_surface_destroy(surface);
	if (handle == 0) SWT.error(SWT.ERROR_NO_HANDLES);
	init();
}

/**
 * Constructs a new Path that is a copy of path. If
 * flatness is less than or equal to zero, an unflatten
 * copy of the path is created. Otherwise, it specifies the maximum
 * error between the path and its flatten copy. Smaller numbers give
 * better approximation.
 * 
 * This operation requires the operating system's advanced
 * graphics subsystem which may not be available on some
 * platforms.
 * 
 * 
 * You must dispose the path when it is no longer required.
 * 
 *
 * @param device the device on which to allocate the path
 * @param path the path to make a copy
 * @param flatness the flatness value
 *
 * @exception IllegalArgumentException 
 *    ERROR_NULL_ARGUMENT - if the device is null and there is no current device
 *    ERROR_NULL_ARGUMENT - if the path is null
 *    ERROR_INVALID_ARGUMENT - if the path has been disposed
 * 
 * @exception SWTException 
 *    ERROR_NO_GRAPHICS_LIBRARY - if advanced graphics are not available
 * 
 * @exception SWTError 
 *    ERROR_NO_HANDLES if a handle for the path could not be obtained
 * 
 *
 * @see #dispose()
 * @since 3.4
 */
public Path (Device device, Path path, float flatness) {
	super(device);
	if (path == null) SWT.error(SWT.ERROR_NULL_ARGUMENT);
	if (path.isDisposed()) SWT.error(SWT.ERROR_INVALID_ARGUMENT);
	long surface = Cairo.cairo_image_surface_create(Cairo.CAIRO_FORMAT_ARGB32, 1, 1);
	if (surface == 0) SWT.error(SWT.ERROR_NO_HANDLES);
	handle = Cairo.cairo_create(surface);
	Cairo.cairo_surface_destroy(surface);
	if (handle == 0) SWT.error(SWT.ERROR_NO_HANDLES);
	long copy;
	flatness = Math.max(0, flatness);
	if (flatness == 0) {
		copy = Cairo.cairo_copy_path(path.handle);
	} else {
		double tolerance = Cairo.cairo_get_tolerance(path.handle);
		Cairo.cairo_set_tolerance(path.handle, flatness);
		copy = Cairo.cairo_copy_path_flat(path.handle);
		Cairo.cairo_set_tolerance(path.handle, tolerance);
	}
	if (copy == 0) {
		Cairo.cairo_destroy(handle);
		SWT.error(SWT.ERROR_NO_HANDLES);
	}
	Cairo.cairo_append_path(handle, copy);
	Cairo.cairo_path_destroy(copy);
	init();
}

/**
 * Constructs a new Path with the specified PathData.
 * 
 * This operation requires the operating system's advanced
 * graphics subsystem which may not be available on some
 * platforms.
 * 
 * 
 * You must dispose the path when it is no longer required.
 * 
 *
 * @param device the device on which to allocate the path
 * @param data the data for the path
 *
 * @exception IllegalArgumentException 
 *    ERROR_NULL_ARGUMENT - if the device is null and there is no current device
 *    ERROR_NULL_ARGUMENT - if the data is null
 * 
 * @exception SWTException 
 *    ERROR_NO_GRAPHICS_LIBRARY - if advanced graphics are not available
 * 
 * @exception SWTError 
 *    ERROR_NO_HANDLES if a handle for the path could not be obtained
 * 
 *
 * @see #dispose()
 * @since 3.4
 */
public Path (Device device, PathData data) {
	this(device);
	if (data == null) SWT.error(SWT.ERROR_NULL_ARGUMENT);
	init(data);
}

/**
 * Adds to the receiver a circular or elliptical arc that lies within
 * the specified rectangular area.
 * 
 * The resulting arc begins at startAngle and extends
 * for arcAngle degrees.
 * Angles are interpreted such that 0 degrees is at the 3 o'clock
 * position. A positive value indicates a counter-clockwise rotation
 * while a negative value indicates a clockwise rotation.
 * 

 * The center of the arc is the center of the rectangle whose origin
 * is (x, y) and whose size is specified by the
 * width and height arguments.
 * 

 * The resulting arc covers an area width + 1 points wide
 * by height + 1 points tall.
 * 
 *
 * @param x the x coordinate of the upper-left corner of the arc
 * @param y the y coordinate of the upper-left corner of the arc
 * @param width the width of the arc
 * @param height the height of the arc
 * @param startAngle the beginning angle
 * @param arcAngle the angular extent of the arc, relative to the start angle
 *
 * @exception SWTException 
 *    ERROR_GRAPHIC_DISPOSED - if the receiver has been disposed
 * 
 */
public void addArc(float x, float y, float width, float height, float startAngle, float arcAngle) {
	if (isDisposed()) SWT.error(SWT.ERROR_GRAPHIC_DISPOSED);
	if (width == 0 || height == 0 || arcAngle == 0) return;
	x = DPIUtil.autoScaleUp(x);
	y = DPIUtil.autoScaleUp(y);
	width = DPIUtil.autoScaleUp(width);
	height = DPIUtil.autoScaleUp(height);
	addArcInPixels(x, y, width, height, startAngle, arcAngle);
}

void addArcInPixels(float x, float y, float width, float height, float startAngle, float arcAngle) {
	moved = true;
	if (width == height) {
		float angle = -startAngle * (float)Math.PI / 180;
		if (closed) Cairo.cairo_move_to(handle, (x + width / 2f) + width / 2f * Math.cos(angle), (y + height / 2f) + height / 2f * Math.sin(angle));
		if (arcAngle >= 0) {
			Cairo.cairo_arc_negative(handle, x + width / 2f, y + height / 2f, width / 2f, angle, -(startAngle + arcAngle) * (float)Math.PI / 180);
		} else {
			Cairo.cairo_arc(handle, x + width / 2f, y + height / 2f, width / 2f, angle, -(startAngle + arcAngle) * (float)Math.PI / 180);
		}
	} else {
		Cairo.cairo_save(handle);
		Cairo.cairo_translate(handle, x + width / 2f, y + height / 2f);
		Cairo.cairo_scale(handle, width / 2f, height / 2f);
		float angle = -startAngle * (float)Math.PI / 180;
		if (closed) Cairo.cairo_move_to(handle, Math.cos(angle), Math.sin(angle));
		if (arcAngle >= 0) {
			Cairo.cairo_arc_negative(handle, 0, 0, 1, angle, -(startAngle + arcAngle) * (float)Math.PI / 180);
		} else {
			Cairo.cairo_arc(handle, 0, 0, 1, angle, -(startAngle + arcAngle) * (float)Math.PI / 180);
		}
		Cairo.cairo_restore(handle);
	}
	closed = false;
	if (Math.abs(arcAngle) >= 360) close();
}

/**
 * Adds to the receiver the path described by the parameter.
 *
 * @param path the path to add to the receiver
 *
 * @exception IllegalArgumentException 
 *    ERROR_NULL_ARGUMENT - if the parameter is null
 *    ERROR_INVALID_ARGUMENT - if the parameter has been disposed
 * 
 * @exception SWTException 
 *    ERROR_GRAPHIC_DISPOSED - if the receiver has been disposed
 * 
 */
public void addPath(Path path) {
	if (isDisposed()) SWT.error(SWT.ERROR_GRAPHIC_DISPOSED);
	if (path == null) SWT.error(SWT.ERROR_NULL_ARGUMENT);
	if (path.isDisposed()) SWT.error(SWT.ERROR_INVALID_ARGUMENT);
	moved = false;
	long copy = Cairo.cairo_copy_path(path.handle);
	if (copy == 0) SWT.error(SWT.ERROR_NO_HANDLES);
	Cairo.cairo_append_path(handle, copy);
	Cairo.cairo_path_destroy(copy);
	closed = path.closed;
}

/**
 * Adds to the receiver the rectangle specified by x, y, width and height.
 *
 * @param x the x coordinate of the rectangle to add
 * @param y the y coordinate of the rectangle to add
 * @param width the width of the rectangle to add
 * @param height the height of the rectangle to add
 *
 * @exception SWTException 
 *    ERROR_GRAPHIC_DISPOSED - if the receiver has been disposed
 * 
 */
public void addRectangle(float x, float y, float width, float height) {
	if (isDisposed()) SWT.error(SWT.ERROR_GRAPHIC_DISPOSED);
	x = DPIUtil.autoScaleUp(x);
	y = DPIUtil.autoScaleUp(y);
	width = DPIUtil.autoScaleUp(width);
	height = DPIUtil.autoScaleUp(height);
	addRectangleInPixels(x, y, width, height);
}

void addRectangleInPixels(float x, float y, float width, float height) {
	moved = false;
	Cairo.cairo_rectangle(handle, x, y, width, height);
	closed = true;
}

/**
 * Adds to the receiver the pattern of glyphs generated by drawing
 * the given string using the given font starting at the point (x, y).
 *
 * @param string the text to use
 * @param x the x coordinate of the starting point
 * @param y the y coordinate of the starting point
 * @param font the font to use
 *
 * @exception IllegalArgumentException 
 *    ERROR_NULL_ARGUMENT - if the font is null
 *    ERROR_INVALID_ARGUMENT - if the font has been disposed
 * 
 * @exception SWTException 
 *    ERROR_GRAPHIC_DISPOSED - if the receiver has been disposed
 * 
 */
public void addString(String string, float x, float y, Font font) {
	if (isDisposed()) SWT.error(SWT.ERROR_GRAPHIC_DISPOSED);
	if (font == null) SWT.error(SWT.ERROR_NULL_ARGUMENT);
	if (font.isDisposed()) SWT.error(SWT.ERROR_INVALID_ARGUMENT);
	x = DPIUtil.autoScaleUp(x);
	y = DPIUtil.autoScaleUp(y);
	// Scale up the font
	FontData fd = font.getFontData()[0];
	fd.setHeight(DPIUtil.autoScaleUp(fd.getHeight()));
	Font scaledFont = new Font(font.getDevice(), fd);
	addStringInPixels(string, x, y, scaledFont);
	scaledFont.dispose(); // Dispose the scaled up font
}
void addStringInPixels(String string, float x, float y, Font font) {
	moved = false;
	GC.addCairoString(handle, string, x, y, font);
	closed = true;
}

/**
 * Closes the current sub path by adding to the receiver a line
 * from the current point of the path back to the starting point
 * of the sub path.
 *
 * @exception SWTException 
 *    ERROR_GRAPHIC_DISPOSED - if the receiver has been disposed
 * 
 */
public void close() {
	if (isDisposed()) SWT.error(SWT.ERROR_GRAPHIC_DISPOSED);
	Cairo.cairo_close_path(handle);
	moved = false;
	closed = true;
}

/**
 * Returns true if the specified point is contained by
 * the receiver and false otherwise.
 * 
 * If outline is true, the point (x, y) checked for containment in
 * the receiver's outline. If outline is false, the point is
 * checked to see if it is contained within the bounds of the (closed) area
 * covered by the receiver.
 *
 * @param x the x coordinate of the point to test for containment
 * @param y the y coordinate of the point to test for containment
 * @param gc the GC to use when testing for containment
 * @param outline controls whether to check the outline or contained area of the path
 * @return true if the path contains the point and false otherwise
 *
 * @exception IllegalArgumentException 

 *    ERROR_NULL_ARGUMENT - if the gc is null
 *    ERROR_INVALID_ARGUMENT - if the gc has been disposed
 * 
 * @exception SWTException 
 *    ERROR_GRAPHIC_DISPOSED - if the receiver has been disposed
 * 
 */
public boolean contains(float x, float y, GC gc, boolean outline) {
	if (isDisposed()) SWT.error(SWT.ERROR_GRAPHIC_DISPOSED);
	if (gc == null) SWT.error(SWT.ERROR_NULL_ARGUMENT);
	if (gc.isDisposed()) SWT.error(SWT.ERROR_INVALID_ARGUMENT);
	x = DPIUtil.autoScaleUp(x);
	y = DPIUtil.autoScaleUp(y);
	return containsInPixels(x, y, gc, outline);
}
boolean containsInPixels(float x, float y, GC gc, boolean outline) {
	//TODO - see Windows
	gc.initCairo();
	gc.checkGC(GC.LINE_CAP | GC.LINE_JOIN | GC.LINE_STYLE | GC.LINE_WIDTH);
	boolean result = false;
	long cairo = gc.data.cairo;
	long copy = Cairo.cairo_copy_path(handle);
	if (copy == 0) SWT.error(SWT.ERROR_NO_HANDLES);
	Cairo.cairo_append_path(cairo, copy);
	Cairo.cairo_path_destroy(copy);
	if (outline) {
		result = Cairo.cairo_in_stroke(cairo, x, y) != 0;
	} else {
		result = Cairo.cairo_in_fill(cairo, x, y) != 0;
	}
	Cairo.cairo_new_path(cairo);
	return result;
}

/**
 * Adds to the receiver a cubic bezier curve based on the parameters.
 *
 * @param cx1 the x coordinate of the first control point of the spline
 * @param cy1 the y coordinate of the first control of the spline
 * @param cx2 the x coordinate of the second control of the spline
 * @param cy2 the y coordinate of the second control of the spline
 * @param x the x coordinate of the end point of the spline
 * @param y the y coordinate of the end point of the spline
 *
 * @exception SWTException 
 *    ERROR_GRAPHIC_DISPOSED - if the receiver has been disposed
 * 
 */
public void cubicTo(float cx1, float cy1, float cx2, float cy2, float x, float y) {
	if (isDisposed()) SWT.error(SWT.ERROR_GRAPHIC_DISPOSED);
	cx1 = DPIUtil.autoScaleUp(cx1);
	cy1 = DPIUtil.autoScaleUp(cy1);
	cx2 = DPIUtil.autoScaleUp(cx2);
	cy2 = DPIUtil.autoScaleUp(cy2);
	x = DPIUtil.autoScaleUp(x);
	y = DPIUtil.autoScaleUp(y);
	cubicToInPixels(cx1, cy1, cx2, cy2, x, y);
}
void cubicToInPixels(float cx1, float cy1, float cx2, float cy2, float x, float y) {
	if (!moved) {
		double[] currentX = new double[1], currentY = new double[1];
		Cairo.cairo_get_current_point(handle, currentX, currentY);
		Cairo.cairo_move_to(handle, currentX[0], currentY[0]);
		moved = true;
	}
	Cairo.cairo_curve_to(handle, cx1, cy1, cx2, cy2, x, y);
	closed = false;
}

/**
 * Replaces the first four elements in the parameter with values that
 * describe the smallest rectangle that will completely contain the
 * receiver (i.e. the bounding box).
 *
 * @param bounds the array to hold the result
 *
 * @exception IllegalArgumentException 
 *    ERROR_NULL_ARGUMENT - if the parameter is null
 *    ERROR_INVALID_ARGUMENT - if the parameter is too small to hold the bounding box
 * 
 * @exception SWTException 
 *    ERROR_GRAPHIC_DISPOSED - if the receiver has been disposed
 * 
 */
public void getBounds(float[] bounds) {
	if (isDisposed()) SWT.error(SWT.ERROR_GRAPHIC_DISPOSED);
	if (bounds == null) SWT.error(SWT.ERROR_NULL_ARGUMENT);
	if (bounds.length < 4) SWT.error(SWT.ERROR_INVALID_ARGUMENT);
	getBoundsInPixels(bounds);
	for (int i = 0; i < bounds.length; i++) {
		bounds [i] = DPIUtil.autoScaleDown(bounds[i]);
	}
}
void getBoundsInPixels(float[] bounds) {
	long copy = Cairo.cairo_copy_path(handle);
	if (copy == 0) SWT.error(SWT.ERROR_NO_HANDLES);
	cairo_path_t path = new cairo_path_t();
	Cairo.memmove(path, copy, cairo_path_t.sizeof);
	double minX = 0, minY = 0, maxX = 0, maxY = 0;
	if (path.num_data > 0) {
		minX = minY = Double.POSITIVE_INFINITY;
		maxX = maxY = Double.NEGATIVE_INFINITY;
		int i = 0;
		double[] points = new double[6];
		cairo_path_data_t data = new cairo_path_data_t();
		while (i < path.num_data) {
			long offset = path.data + i * cairo_path_data_t.sizeof;
			Cairo.memmove(data, offset, cairo_path_data_t.sizeof);
			switch (data.type) {
				case Cairo.CAIRO_PATH_MOVE_TO:
					Cairo.memmove(points, offset + cairo_path_data_t.sizeof, cairo_path_data_t.sizeof);
					minX = Math.min(minX, points[0]);
					minY = Math.min(minY, points[1]);
					maxX = Math.max(maxX, points[0]);
					maxY = Math.max(maxY, points[1]);
					break;
				case Cairo.CAIRO_PATH_LINE_TO:
					Cairo.memmove(points, offset + cairo_path_data_t.sizeof, cairo_path_data_t.sizeof);
					minX = Math.min(minX, points[0]);
					minY = Math.min(minY, points[1]);
					maxX = Math.max(maxX, points[0]);
					maxY = Math.max(maxY, points[1]);
					break;
				case Cairo.CAIRO_PATH_CURVE_TO:
					Cairo.memmove(points, offset + cairo_path_data_t.sizeof, cairo_path_data_t.sizeof * 3);
					minX = Math.min(minX, points[0]);
					minY = Math.min(minY, points[1]);
					maxX = Math.max(maxX, points[0]);
					maxY = Math.max(maxY, points[1]);
					minX = Math.min(minX, points[2]);
					minY = Math.min(minY, points[3]);
					maxX = Math.max(maxX, points[2]);
					maxY = Math.max(maxY, points[3]);
					minX = Math.min(minX, points[4]);
					minY = Math.min(minY, points[5]);
					maxX = Math.max(maxX, points[4]);
					maxY = Math.max(maxY, points[5]);
					break;
				case Cairo.CAIRO_PATH_CLOSE_PATH: break;
			}
			i += data.length;
		}
	}
	bounds[0] = (float)minX;
	bounds[1] = (float)minY;
	bounds[2] = (float)(maxX - minX);
	bounds[3] = (float)(maxY - minY);
	Cairo.cairo_path_destroy(copy);
}

/**
 * Replaces the first two elements in the parameter with values that
 * describe the current point of the path.
 *
 * @param point the array to hold the result
 *
 * @exception IllegalArgumentException 
 *    ERROR_NULL_ARGUMENT - if the parameter is null
 *    ERROR_INVALID_ARGUMENT - if the parameter is too small to hold the end point
 * 
 * @exception SWTException 
 *    ERROR_GRAPHIC_DISPOSED - if the receiver has been disposed
 * 
 */
public void getCurrentPoint(float[] point) {
	if (isDisposed()) SWT.error(SWT.ERROR_GRAPHIC_DISPOSED);
	getCurrentPointInPixels(point);
	for (int i = 0; i < point.length; i++) {
		point [i] = DPIUtil.autoScaleDown(point[i]);
	}
}

void getCurrentPointInPixels(float[] point) {
	if (point == null) SWT.error(SWT.ERROR_NULL_ARGUMENT);
	if (point.length < 2) SWT.error(SWT.ERROR_INVALID_ARGUMENT);
	double[] x = new double[1], y = new double[1];
	Cairo.cairo_get_current_point(handle, x, y);
	point[0] = (float)x[0];
	point[1] = (float)y[0];
}

/**
 * Returns a device independent representation of the receiver.
 *
 * @return the PathData for the receiver
 *
 * @exception SWTException 
 *    ERROR_GRAPHIC_DISPOSED - if the receiver has been disposed
 * 
 *
 * @see PathData
 */
public PathData getPathData() {
	if (isDisposed()) SWT.error(SWT.ERROR_GRAPHIC_DISPOSED);
	PathData result = getPathDataInPixels();
	result.points = DPIUtil.autoScaleDown(result.points);
	return result;
}

PathData getPathDataInPixels() {
	long copy = Cairo.cairo_copy_path(handle);
	if (copy == 0) SWT.error(SWT.ERROR_NO_HANDLES);
	cairo_path_t path = new cairo_path_t();
	Cairo.memmove(path, copy, cairo_path_t.sizeof);
	byte[] types = new byte[path.num_data];
	float[] pts = new float[path.num_data * 6];
	int typeIndex = 0, ptsIndex = 0;
	if (path.num_data > 0) {
		int i = 0;
		double[] points = new double[6];
		cairo_path_data_t data = new cairo_path_data_t();
		while (i < path.num_data) {
			long offset = path.data + i * cairo_path_data_t.sizeof;
			Cairo.memmove(data, offset, cairo_path_data_t.sizeof);
			switch (data.type) {
				case Cairo.CAIRO_PATH_MOVE_TO:
					types[typeIndex++] = SWT.PATH_MOVE_TO;
					Cairo.memmove(points, offset + cairo_path_data_t.sizeof, cairo_path_data_t.sizeof);
					pts[ptsIndex++] = (float)points[0];
					pts[ptsIndex++] = (float)points[1];
					break;
				case Cairo.CAIRO_PATH_LINE_TO:
					types[typeIndex++] = SWT.PATH_LINE_TO;
					Cairo.memmove(points, offset + cairo_path_data_t.sizeof, cairo_path_data_t.sizeof);
					pts[ptsIndex++] = (float)points[0];
					pts[ptsIndex++] = (float)points[1];
					break;
				case Cairo.CAIRO_PATH_CURVE_TO:
					types[typeIndex++] = SWT.PATH_CUBIC_TO;
					Cairo.memmove(points, offset + cairo_path_data_t.sizeof, cairo_path_data_t.sizeof * 3);
					pts[ptsIndex++] = (float)points[0];
					pts[ptsIndex++] = (float)points[1];
					pts[ptsIndex++] = (float)points[2];
					pts[ptsIndex++] = (float)points[3];
					pts[ptsIndex++] = (float)points[4];
					pts[ptsIndex++] = (float)points[5];
					break;
				case Cairo.CAIRO_PATH_CLOSE_PATH:
					types[typeIndex++] = SWT.PATH_CLOSE;
					break;
			}
			i += data.length;
		}
	}
	if (typeIndex != types.length) {
		byte[] newTypes = new byte[typeIndex];
		System.arraycopy(types, 0, newTypes, 0, typeIndex);
		types = newTypes;
	}
	if (ptsIndex != pts.length) {
		float[] newPts = new float[ptsIndex];
		System.arraycopy(pts, 0, newPts, 0, ptsIndex);
		pts = newPts;
	}
	Cairo.cairo_path_destroy(copy);
	PathData result = new PathData();
	result.types = types;
	result.points = pts;
	return result;
}

/**
 * Adds to the receiver a line from the current point to
 * the point specified by (x, y).
 *
 * @param x the x coordinate of the end of the line to add
 * @param y the y coordinate of the end of the line to add
 *
 * @exception SWTException 
 *    ERROR_GRAPHIC_DISPOSED - if the receiver has been disposed
 * 
 */
public void lineTo(float x, float y) {
	if (isDisposed()) SWT.error(SWT.ERROR_GRAPHIC_DISPOSED);
	x = DPIUtil.autoScaleUp(x);
	y = DPIUtil.autoScaleUp(y);
	lineToInPixels(x, y);
}
void lineToInPixels(float x, float y) {
	if (!moved) {
		double[] currentX = new double[1], currentY = new double[1];
		Cairo.cairo_get_current_point(handle, currentX, currentY);
		Cairo.cairo_move_to(handle, currentX[0], currentY[0]);
		moved = true;
	}
	Cairo.cairo_line_to(handle, x, y);
	closed = false;
}

/**
 * Sets the current point of the receiver to the point
 * specified by (x, y). Note that this starts a new
 * sub path.
 *
 * @param x the x coordinate of the new end point
 * @param y the y coordinate of the new end point
 *
 * @exception SWTException 
 *    ERROR_GRAPHIC_DISPOSED - if the receiver has been disposed
 * 
 */
public void moveTo(float x, float y) {
	if (isDisposed()) SWT.error(SWT.ERROR_GRAPHIC_DISPOSED);
	x = DPIUtil.autoScaleUp(x);
	y = DPIUtil.autoScaleUp(y);
	moveToInPixels(x, y);
}
void moveToInPixels(float x, float y) {
	/*
	* Bug in Cairo.  If cairo_move_to() is not called at the
	* begining of a subpath, the first cairo_line_to() or
	* cairo_curve_to() segment do not output anything.  The fix
	* is to detect that the app did not call cairo_move_to()
	* before those calls and call it explicitly.
	*/
	moved = true;
	Cairo.cairo_move_to(handle, x, y);
	closed = true;
}

/**
 * Adds to the receiver a quadratic curve based on the parameters.
 *
 * @param cx the x coordinate of the control point of the spline
 * @param cy the y coordinate of the control point of the spline
 * @param x the x coordinate of the end point of the spline
 * @param y the y coordinate of the end point of the spline
 *
 * @exception SWTException 
 *    ERROR_GRAPHIC_DISPOSED - if the receiver has been disposed
 * 
 */
public void quadTo(float cx, float cy, float x, float y) {
	if (isDisposed()) SWT.error(SWT.ERROR_GRAPHIC_DISPOSED);
	x = DPIUtil.autoScaleUp(x);
	y = DPIUtil.autoScaleUp(y);
	cx = DPIUtil.autoScaleUp(cx);
	cy = DPIUtil.autoScaleUp(cy);
	quadToInPixels(cx, cy, x, y);
}
void quadToInPixels(float cx, float cy, float x, float y) {
	double[] currentX = new double[1], currentY = new double[1];
	Cairo.cairo_get_current_point(handle, currentX, currentY);
	if (!moved) {
		Cairo.cairo_move_to(handle, currentX[0], currentY[0]);
		moved = true;
	}
	float x0 = (float)currentX[0];
	float y0 = (float)currentY[0];
	float cx1 = x0 + 2 * (cx - x0) / 3;
	float cy1 = y0 + 2 * (cy - y0) / 3;
	float cx2 = cx1 + (x - x0) / 3;
	float cy2 = cy1 + (y - y0) / 3;
	Cairo.cairo_curve_to(handle, cx1, cy1, cx2, cy2, x, y);
	closed = false;
}

@Override
void destroy() {
	Cairo.cairo_destroy(handle);
	handle = 0;
}

void init(PathData data) {
	byte[] types = data.types;
	float[] points = data.points;
	for (int i = 0, j = 0; i < types.length; i++) {
		switch (types[i]) {
			case SWT.PATH_MOVE_TO:
				moveTo(points[j++], points[j++]);
				break;
			case SWT.PATH_LINE_TO:
				lineTo(points[j++], points[j++]);
				break;
			case SWT.PATH_CUBIC_TO:
				cubicTo(points[j++], points[j++], points[j++], points[j++], points[j++], points[j++]);
				break;
			case SWT.PATH_QUAD_TO:
				quadTo(points[j++], points[j++], points[j++], points[j++]);
				break;
			case SWT.PATH_CLOSE:
				close();
				break;
			default:
				dispose();
				SWT.error(SWT.ERROR_INVALID_ARGUMENT);
		}
	}
}

/**
 * Returns true if the Path has been disposed,
 * and false otherwise.
 * 
 * This method gets the dispose state for the Path.
 * When a Path has been disposed, it is an error to
 * invoke any other method (except {@link #dispose()}) using the Path.
 *
 * @return true when the Path is disposed, and false otherwise
 */
@Override
public boolean isDisposed() {
	return handle == 0;
}

/**
 * Returns a string containing a concise, human-readable
 * description of the receiver.
 *
 * @return a string representation of the receiver
 */
@Override
public String toString() {
	if (isDisposed()) return "Path {*DISPOSED*}";
	return "Path {" + handle + "}";
}

}