Axis.java

/*******************************************************************************
 * Copyright (c) 2010 Oak Ridge National Laboratory.
 * All rights reserved. This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License v1.0
 * which accompanies this distribution, and is available at
 * http://www.eclipse.org/legal/epl-v10.html
 ******************************************************************************/
package org.eclipse.nebula.visualization.xygraph.figures;

import java.util.ArrayList;
import java.util.List;

import org.eclipse.draw2d.FigureUtilities;
import org.eclipse.draw2d.Graphics;
import org.eclipse.draw2d.MouseEvent;
import org.eclipse.draw2d.MouseListener;
import org.eclipse.draw2d.MouseMotionListener;
import org.eclipse.draw2d.geometry.Dimension;
import org.eclipse.draw2d.geometry.Point;
import org.eclipse.nebula.visualization.internal.xygraph.undo.AxisPanOrZoomCommand;
import org.eclipse.nebula.visualization.internal.xygraph.undo.SaveStateCommand;
import org.eclipse.nebula.visualization.xygraph.dataprovider.IDataProvider;
import org.eclipse.nebula.visualization.xygraph.linearscale.LinearScale;
import org.eclipse.nebula.visualization.xygraph.linearscale.Range;
import org.eclipse.nebula.visualization.xygraph.util.GraphicsUtil;
import org.eclipse.nebula.visualization.xygraph.util.Log10;
import org.eclipse.nebula.visualization.xygraph.util.SWTConstants;
import org.eclipse.nebula.visualization.xygraph.util.XYGraphMediaFactory;
import org.eclipse.swt.SWT;
import org.eclipse.swt.graphics.Color;
import org.eclipse.swt.graphics.Cursor;
import org.eclipse.swt.graphics.Font;
import org.eclipse.swt.graphics.FontData;
import org.eclipse.swt.graphics.RGB;
import org.eclipse.swt.widgets.Display;

/**
 * The axis figure.
 *
 * @author Xihui Chen
 * @author Kay Kasemir - Axis zoom/pan tweaks
 */
public class Axis extends LinearScale {
	/** The ratio of the shrink/expand area for one zoom. */
	final static double ZOOM_RATIO = 0.1;

	/** The auto zoom interval in ms. */
	final static int ZOOM_SPEED = 200;

	// private static final Color GRAY_COLOR =
	// XYGraphMediaFactory.getInstance().getColor(
	// XYGraphMediaFactory.COLOR_GRAY);

	private String title;

	@Override
	public void setFont(Font font) {
		super.setFont(font);
		this.scaleFontData = getFont().getFontData()[0];
	}

	private final List<Trace> traceList = new ArrayList<Trace>();

	private IXYGraph xyGraph;
	private Grid grid;

	private Font titleFont;
	// title FontData : Add because of SWT illegal thread access
	private FontData titleFontData;

	// title FontData : Add because of SWT illegal thread access
	private FontData scaleFontData;

	private boolean autoScale = false;

	private boolean showMajorGrid = false;

	private boolean showMinorGrid = false;

	private boolean isInverted = false;

	private Color majorGridColor;

	private Color minorGridColor;

	private boolean dashGridLine = true;

	private double autoScaleThreshold = 0.01;

	protected final List<IAxisListener> listeners = new ArrayList<IAxisListener>();

	private ZoomType zoomType = ZoomType.NONE;

	private Point start;
	private Point end;
	private boolean armed;
	private Range startRange;
	private final Cursor grabbing;
	private Color revertBackColor;

	private RGB colorRGB;
	private RGB majorGridColorRGB;

	public FontData getTitleFontData() {
		return titleFontData;
	}

	public FontData getScaleFontData() {
		return scaleFontData;
	}

	/**
	 * Constructor
	 * 
	 * @param title
	 *            title of the axis
	 * @param yAxis
	 *            true if this is the Y-Axis, false if this is the X-Axis.
	 */
	public Axis(final String title, final boolean yAxis) {
		super();
		this.title = title;
		if (yAxis)
			setOrientation(Orientation.VERTICAL);
		// Save drawing line operation in RAP.
		if (GraphicsUtil.isRAP())
			setMinorTicksVisible(false);

		final AxisMouseListener panner = new AxisMouseListener();
		addMouseListener(panner);
		addMouseMotionListener(panner);
		grabbing = XYGraphMediaFactory.getInstance().getCursor(XYGraphMediaFactory.CURSOR_GRABBING_ON_AXIS_PATH);
		Font sysFont = Display.getCurrent().getSystemFont();
		titleFont = XYGraphMediaFactory.getInstance()
				.getFont(new FontData(sysFont.getFontData()[0].getName(), 12, SWT.BOLD)); // $NON-NLS-1$
		if (getBackgroundColor() != null) {
			RGB backRGB = getBackgroundColor().getRGB();
			revertBackColor = XYGraphMediaFactory.getInstance().getColor(255 - backRGB.red, 255 - backRGB.green,
					255 - backRGB.blue);
		} else
			revertBackColor = XYGraphMediaFactory.getInstance().getColor(100, 100, 100);

	}

	public void addListener(final IAxisListener listener) {
		if (listeners.contains(listener))
			return;
		listeners.add(listener);
	}

	public boolean removeListener(final IAxisListener listener) {
		return listeners.remove(listener);
	}

	protected void fireRevalidated() {
		for (IAxisListener listener : listeners)
			listener.axisRevalidated(this);
	}

	protected void fireAxisRangeChanged(final Range old_range, final Range new_range) {
		for (IAxisListener listener : listeners)
			listener.axisRangeChanged(this, old_range, new_range);
	}

	@Override
	public void setRange(final double lower, final double upper) {
		Range old_range = getRange();
		super.setRange(lower, upper);
		fireAxisRangeChanged(old_range, getRange());
	}

	/**
	 * Inverts the axis if set to True
	 * 
	 * @param isInverted
	 */
	public void setInverted(boolean isInverted) {
		if (this.isInverted == isInverted)
			return;

		this.isInverted = isInverted;
		double min = getRange().getLower();
		double max = getRange().getUpper();
		if ((isInverted && (min < max)) || (!isInverted && (min > max))) {
			setRange(new Range(max, min));
		}
		xyGraph.repaint();
	}

	/**
	 * Returns True if axis is inverted, False otherwise
	 * 
	 * @return
	 */
	public boolean isInverted() {
		return isInverted;
	}

	@Override
	protected void layout() {
		super.layout();
		fireRevalidated();
	}

	@Override
	public void setVisible(boolean visible) {
		super.setVisible(visible);
		revalidate();
	}

	@Override
	public void setForegroundColor(final Color color) {
		Color oldColor = getForegroundColor();
		super.setForegroundColor(color);
		colorRGB = color.getRGB();
		if (xyGraph != null)
			xyGraph.repaint();
		fireAxisForegroundColorChanged(oldColor, color);
	}

	@Override
	public void setMinorTicksVisible(boolean minorTicksVisible) {
		// Save line operation in RAP.
		if (GraphicsUtil.isRAP())
			super.setMinorTicksVisible(false);
		else
			super.setMinorTicksVisible(minorTicksVisible);
	}

	public RGB getForegroundColorRGB() {
		return colorRGB;
	}

	private void fireAxisForegroundColorChanged(Color oldColor, Color newColor) {
		for (IAxisListener listener : listeners)
			listener.axisForegroundColorChanged(this, oldColor, newColor);
	}

	@Override
	public void setBackgroundColor(Color bg) {
		RGB backRGB = bg.getRGB();
		revertBackColor = XYGraphMediaFactory.getInstance().getColor(255 - backRGB.red, 255 - backRGB.green,
				255 - backRGB.blue);
		super.setBackgroundColor(bg);
	}

	@Override
	public Dimension getPreferredSize(final int wHint, final int hHint) {
		final Dimension d = super.getPreferredSize(wHint, hHint);
		if (isVisible()) {
			if (isHorizontal())
				d.height += FigureUtilities.getTextExtents(title, titleFont).height;
			else
				d.width += FigureUtilities.getTextExtents(title, titleFont).height;
		} else { // Not visible, flatten it to use zero height resp. width
			if (isHorizontal())
				d.height = 0;
			else
				d.width = 0;
		}
		return d;
	}

	@Override
	protected void paintClientArea(final Graphics graphics) {
		// Don't do anything when hidden
		if (!isVisible())
			return;

		super.paintClientArea(graphics);

		// graphics.pushState();
		graphics.setFont(titleFont);
		final Dimension titleSize = FigureUtilities.getTextExtents(title, titleFont);
		if (isHorizontal()) {
			if (getTickLabelSide() == LabelSide.Primary)
				graphics.drawText(title, bounds.x + bounds.width / 2 - titleSize.width / 2,
						bounds.y + bounds.height - titleSize.height);
			else
				graphics.drawText(title, bounds.x + bounds.width / 2 - titleSize.width / 2, bounds.y);
		} else {
			final int w = titleSize.height;
			final int h = titleSize.width + 1;

			if (getTickLabelSide() == LabelSide.Primary) {
				GraphicsUtil.drawVerticalText(graphics, title, bounds.x, bounds.y + bounds.height / 2 - h / 2, false);
			} else {
				GraphicsUtil.drawVerticalText(graphics, title, bounds.x + bounds.width - w,
						bounds.y + bounds.height / 2 - h / 2, true);
			}
		}

		// graphics.popState();

		// Show the start/end cursor or the 'rubberband' of a zoom operation?
		if (armed && end != null && start != null) {
			switch (zoomType) {
			case RUBBERBAND_ZOOM:
			case HORIZONTAL_ZOOM:
			case VERTICAL_ZOOM:
			case DYNAMIC_ZOOM:
				graphics.setLineStyle(SWTConstants.LINE_DOT);
				graphics.setLineWidth(1);
				graphics.setForegroundColor(revertBackColor);
				graphics.drawRectangle(start.x, start.y, end.x - start.x - 1, end.y - start.y - 1);
				break;

			default:
				break;
			}
		}
	}

	/**
	 * @return Range that reflects the minimum and maximum value of all traces
	 *         on this axis. Returns <code>null</code> if there is no trace
	 *         data.
	 */
	public Range getTraceDataRange() {
		double low = Double.POSITIVE_INFINITY;
		double high = Double.NEGATIVE_INFINITY;
		for (Trace trace : traceList) {
			if (trace.getDataProvider() == null || !trace.isVisible())
				continue;
			final Range range;
			if (isHorizontal())
				range = trace.getDataProvider().getXDataMinMax();
			else
				range = trace.getDataProvider().getYDataMinMax();
			if (range == null)
				continue;
			if (Double.isInfinite(range.getLower()) || Double.isInfinite(range.getUpper())
					|| Double.isNaN(range.getLower()) || Double.isNaN(range.getUpper()))
				continue;
			if (low > range.getLower())
				low = range.getLower();
			if (high < range.getUpper())
				high = range.getUpper();
		}
		if (Double.isInfinite(low) || Double.isInfinite(high))
			return null;
		return new Range(low, high);
	}

	/**
	 * Perform an auto-scale: Axis limits are set to the value range of the
	 * traces on this axis. Includes some optimization: Axis range is set a
	 * little wider than exact trace data range. When auto-scale would only
	 * perform a minor axis adjustment, axis is left unchanged.
	 *
	 * @param force
	 *            If true, the axis will be auto-scaled by force regardless the
	 *            autoScale field. Otherwise, it will use the autoScale field to
	 *            judge whether an auto-scale will be performed.
	 * @return true if the axis is repainted due to range change.
	 *
	 * @see #autoScaleThreshold
	 */
	public boolean performAutoScale(final boolean force) {
		// Anything to do? Autoscale not enabled nor forced?
		if (traceList.size() <= 0 || !(force || autoScale))
			return false;

		// Idea: Stop Autoscale on XYGraph whenever one of the Zoom buttons is
		// toggled!
		// Seems reasonable, but doesn't work:
		// User may have selected HORIZONTAL_ZOOM to configure a time range,
		// but still expects the vertical value axes to auto-zoom.
		// Or user selected a VERTICAL_ZOOM to adjust _one_ axis,
		// but still expects _other_ vertical axes to auto-zoom
		// -> Since the zoom type is not specific to a certain axis,
		// it is impossible to determine if maybe _this_ axis
		// should suspend auto-zoom.
		// -> Just to the auto-zoom, don't second-guess.
		// Above sounds correct, but it is not a good user experience.
		if (!force && xyGraph.getZoomType() != ZoomType.NONE)
			return false;

		// Get range of data in all traces
		final Range range = getTraceDataRange();
		if (range == null)
			return false;
		double tempMin = range.getLower();
		double tempMax = range.getUpper();

		// Get current axis range, determine how 'different' they are
		double max = getRange().getUpper();
		double min = getRange().getLower();

		if (isLogScaleEnabled()) {
			if (tempMax <= 0) {
				tempMax = 1;
			}
			if (tempMin <= 0) {
				tempMin = 0.1;
			}
			// Transition into log space
			tempMin = Log10.log10(tempMin);
			tempMax = Log10.log10(tempMax);
			max = Log10.log10(max);
			min = Log10.log10(min);
		}

		double thr = (tempMax - tempMin) * autoScaleThreshold;

		if (tempMax == tempMin) {
			if (tempMax == 0) {
				thr = autoScaleThreshold;
			} else {
				thr = Math.abs(tempMax) * autoScaleThreshold;
			}
		}

		// if both the changes are lower than threshold, return
		if (((tempMin - min) >= thr / 2 && (tempMin - min) <= thr)
				&& ((max - tempMax) >= thr / 2 && (max - tempMax) <= thr)) {
			return false;
		} else { // expand more space than needed
			if ((tempMin - min) <= thr / 2 || (tempMin - min) > thr)
				tempMin -= thr;
			else
				tempMin = min;
			if ((max - tempMax) <= thr / 2 || (max - tempMax) > thr)
				tempMax += thr;
			else
				tempMax = max;
		}

		// Any change at all?
		if ((Double.doubleToLongBits(tempMin) == Double.doubleToLongBits(min)
				&& Double.doubleToLongBits(tempMax) == Double.doubleToLongBits(max)) || Double.isInfinite(tempMin)
				|| Double.isInfinite(tempMax) || Double.isNaN(tempMin) || Double.isNaN(tempMax))
			return false;

		if (isLogScaleEnabled()) { // Revert from log space
			tempMin = Log10.pow10(tempMin);
			tempMax = Log10.pow10(tempMax);
		}

		// Update axis
		setRange(tempMin, tempMax, true);
		repaint();
		return true;
	}

	/**
	 * Add a trace to the axis.
	 * 
	 * @param trace
	 *            the trace to be added.
	 */
	public void addTrace(final Trace trace) {
		if (traceList.contains(trace))
			return;
		traceList.add(trace);
		addListener(trace);
		performAutoScale(false);
	}

	/**
	 * Remove a trace from the axis.
	 * 
	 * @param trace
	 * @return true if this axis contained the specified trace
	 */
	public boolean removeTrace(final Trace trace) {
		final boolean r = traceList.remove(trace);
		removeListener(trace);
		performAutoScale(false);
		return r;
	}

	/**
	 * @param title
	 *            the title to set
	 */
	public void setTitle(final String title) {

		String oldTitle = this.title;
		this.title = title;
		if (xyGraph != null)
			xyGraph.repaint();
		fireAxisTitleChanged(oldTitle, title);
	}

	private void fireAxisTitleChanged(String oldTitle, String newTitle) {
		for (IAxisListener listener : listeners)
			listener.axisTitleChanged(this, oldTitle, newTitle);
	}

	/**
	 * @return the title
	 */
	public String getTitle() {
		return title;
	}

	/**
	 * @return the autoScale
	 */
	public boolean isAutoScale() {
		return autoScale;
	}

	/**
	 * @param autoScale
	 *            the autoScale to set
	 */
	public void setAutoScale(final boolean autoScale) {

		boolean oldAutoScale = this.autoScale;
		this.autoScale = autoScale;
		performAutoScale(false);
		fireAxisAutoScaleChanged(oldAutoScale, this.autoScale);
	}

	private void fireAxisAutoScaleChanged(boolean oldAutoScale, boolean newAutoScale) {
		for (IAxisListener listener : listeners)
			listener.axisAutoScaleChanged(this, oldAutoScale, newAutoScale);

	}

	/**
	 * @return the showMajorGrid
	 */
	public boolean isShowMajorGrid() {
		return showMajorGrid;
	}

	/**
	 * @param showMajorGrid
	 *            the showMajorGrid to set
	 */
	public void setShowMajorGrid(final boolean showMajorGrid) {
		this.showMajorGrid = showMajorGrid;
		if (xyGraph != null)
			xyGraph.repaint();
	}

	/**
	 * @return the showMinorGrid
	 */
	public boolean isShowMinorGrid() {
		return showMinorGrid;
	}

	/**
	 * @param showMinorGrid
	 *            the showMinorGrid to set
	 */
	public void setShowMinorGrid(final boolean showMinorGrid) {
		this.showMinorGrid = showMinorGrid;
		if (xyGraph != null)
			xyGraph.repaint();
	}

	/**
	 * @return the majorGridColor
	 */
	public Color getMajorGridColor() {
		if (majorGridColor == null)
			majorGridColor = XYGraphMediaFactory.getInstance().getColor(XYGraphMediaFactory.COLOR_GRAY);
		return majorGridColor;
	}

	/**
	 * @param majorGridColor
	 *            the majorGridColor to set
	 */
	public void setMajorGridColor(final Color majorGridColor) {
		this.majorGridColor = majorGridColor;
		this.majorGridColorRGB = majorGridColor.getRGB();
		if (xyGraph != null)
			xyGraph.repaint();
	}

	public RGB getMajorGridColorRGB() {
		return majorGridColorRGB;
	}

	/**
	 * @return the minorGridColor
	 */
	public Color getMinorGridColor() {
		if (minorGridColor == null)
			minorGridColor = XYGraphMediaFactory.getInstance().getColor(XYGraphMediaFactory.COLOR_GRAY);
		return minorGridColor;
	}

	/**
	 * @param minorGridColor
	 *            the minorGridColor to set
	 */
	public void setMinorGridColor(final Color minorGridColor) {
		this.minorGridColor = minorGridColor;
		if (xyGraph != null)
			xyGraph.repaint();
	}

	/**
	 * @param titleFont
	 *            the titleFont to set
	 */
	public void setTitleFont(final Font titleFont) {
		this.titleFont = titleFont;
		this.titleFontData = titleFont.getFontData()[0];
		repaint();
	}

	/**
	 * @return the dashGridLine
	 */
	public boolean isDashGridLine() {
		return dashGridLine;
	}

	/**
	 * @param dashGridLine
	 *            the dashGridLine to set
	 */
	public void setDashGridLine(final boolean dashGridLine) {
		this.dashGridLine = dashGridLine;
		if (xyGraph != null)
			xyGraph.repaint();
	}

	/**
	 * @param xyGraph
	 *            the xyGraph to set
	 */
	public void setXyGraph(final IXYGraph xyGraph) {
		this.xyGraph = xyGraph;
	}

	/**
	 * @return xyGraph
	 */
	public IXYGraph getXyGraph() {
		return xyGraph;
	}

	/**
	 * Use {@link #setXyGraph(IXYGraph)} instead
	 * 
	 * @param xyGraph
	 *            the xyGraph to set
	 */
	@Deprecated
	public void setXyGraph(final XYGraph xyGraph) {
		this.xyGraph = xyGraph;
	}

	/**
	 * @return traceList
	 */
	protected List<Trace> getTraceList() {
		return traceList;
	}

	@Override
	public String toString() {
		return title;
	}

	public void dataChanged(final IDataProvider dataProvider) {
		if (autoScale)
			performAutoScale(false);
	}

	/**
	 * The autoScaleThreshold must be a value in range [0,1], which represents a
	 * percentage of the plot area for the threshold when autoScale is
	 * performed.The autoScale will performed only if the spare space exceeds
	 * this threshold. So it can reduce the CPU usage by increasing the
	 * threshold.
	 * 
	 * @param autoScaleThreshold
	 *            the autoScaleThreshold to set
	 */
	public void setAutoScaleThreshold(final double autoScaleThreshold) {
		if (autoScaleThreshold > 1 || autoScaleThreshold < 0)
			throw new RuntimeException("The autoScaleThreshold must be a value in range [0,1]!"); //$NON-NLS-1$
		this.autoScaleThreshold = autoScaleThreshold;
	}

	/**
	 * @param zoom
	 *            Zoom Type
	 * @return <code>true</code> if the zoom type is applicable to this axis
	 */
	private boolean isValidZoomType(final ZoomType zoom) {
		return zoom == ZoomType.PANNING || zoom == ZoomType.RUBBERBAND_ZOOM || zoom == ZoomType.DYNAMIC_ZOOM
				|| zoom == ZoomType.ZOOM_IN || zoom == ZoomType.ZOOM_OUT
				|| (isHorizontal() && (zoom == ZoomType.HORIZONTAL_ZOOM || zoom == ZoomType.ZOOM_IN_HORIZONTALLY
						|| zoom == ZoomType.ZOOM_OUT_HORIZONTALLY))
				|| (!isHorizontal() && (zoom == ZoomType.VERTICAL_ZOOM || zoom == ZoomType.ZOOM_OUT_VERTICALLY
						|| zoom == ZoomType.ZOOM_IN_VERTICALLY));
	}

	/**
	 * @param zoomType
	 *            the zoomType to set
	 */
	public void setZoomType(final ZoomType zoomType) {
		this.zoomType = zoomType;
		// Set zoom's cursor if axis allows that type of zoom
		if (isValidZoomType(zoomType))
			setCursor(zoomType.getCursorOnAxis(isHorizontal()));
		else
			setCursor(ZoomType.NONE.getCursor());
	}

	/**
	 * @return the titleFont
	 */
	public Font getTitleFont() {
		return titleFont;
	}

	/**
	 * @return the autoScaleThreshold
	 */
	public double getAutoScaleThreshold() {
		return autoScaleThreshold;
	}

	/**
	 * @return autoScale
	 */
	public boolean getAutoScale() {
		return autoScale;
	}

	/**
	 * Set this axis as Y-Axis or X-Axis.
	 * 
	 * @param isYAxis
	 *            set true if the axis is Y-Axis; false if it is X-Axis.
	 */
	public void setYAxis(boolean isYAxis) {
		if (xyGraph != null)
			xyGraph.removeAxis(this);
		setOrientation(isYAxis ? Orientation.VERTICAL : Orientation.HORIZONTAL);
		if (xyGraph != null)
			xyGraph.addAxis(this);
	}

	/**
	 * Set the axis on primary side (Bottom/Left) or secondary side (Top/Right).
	 * 
	 * @param onPrimarySide
	 *            set true if the axis on primary side(Bottom/Left); false if it
	 *            is not on the primary side of xy graph(Top/Right).
	 */
	public void setPrimarySide(boolean onPrimarySide) {
		setTickLabelSide(onPrimarySide ? LabelSide.Primary : LabelSide.Secondary);
	}

	/**
	 * @return true if the axis is Y-Axis; false if it is X-Axis;
	 */
	public boolean isYAxis() {
		return !isHorizontal();
	}

	/**
	 * @return true if the axis is on the primary side of xy graph(Bottom/Left);
	 *         false if it is on the secondary side(Top/Right).
	 */
	public boolean isOnPrimarySide() {
		return getTickLabelSide() == LabelSide.Primary;
	}

	/** Pan axis according to start/end from mouse listener */
	private void pan() {
		if (isHorizontal())
			pan(startRange, getPositionValue(start.x, false), getPositionValue(end.x, false));
		else
			pan(startRange, getPositionValue(start.y, false), getPositionValue(end.y, false));
	}

	/**
	 * Pan the axis
	 * 
	 * @param temp
	 *            Original axis range before the panning started
	 * @param t1
	 *            Start of the panning move
	 * @param t2
	 *            End of the panning move
	 */
	protected void pan(final Range temp, double t1, double t2) {
		if (isLogScaleEnabled()) {
			final double m = Math.log10(t2) - Math.log10(t1);
			t1 = Math.pow(10, Math.log10(temp.getLower()) - m);
			t2 = Math.pow(10, Math.log10(temp.getUpper()) - m);
		} else {
			final double m = t2 - t1;
			t1 = temp.getLower() - m;
			t2 = temp.getUpper() - m;
		}
		setRange(t1, t2);
	}

	/**
	 * Zoom axis
	 * 
	 * @param center
	 *            Axis position at the 'center' of the zoom
	 * @param factor
	 *            Zoom factor. Positive to zoom 'in', negative 'out'.
	 */
	public void zoomInOut(final double center, final double factor) {
		final double t1, t2;
		if (isLogScaleEnabled()) {
			final double l = Math.log10(getRange().getUpper()) - Math.log10(getRange().getLower());
			final double r1 = (Math.log10(center) - Math.log10(getRange().getLower())) / l;
			final double r2 = (Math.log10(getRange().getUpper()) - Math.log10(center)) / l;
			t1 = Math.pow(10, Math.log10(getRange().getLower()) + r1 * factor * l);
			t2 = Math.pow(10, Math.log10(getRange().getUpper()) - r2 * factor * l);
		} else {
			final double l = getRange().getUpper() - getRange().getLower();
			final double r1 = (center - getRange().getLower()) / l;
			final double r2 = (getRange().getUpper() - center) / l;
			t1 = getRange().getLower() + r1 * factor * l;
			t2 = getRange().getUpper() - r2 * factor * l;
		}
		setRange(t1, t2, true);
	}

	/**
	 * @param grid
	 *            the grid to set
	 */
	public void setGrid(Grid grid) {
		this.grid = grid;
	}

	/**
	 * @return the grid
	 */
	public Grid getGrid() {
		return grid;
	}

	@Override
	public void setLogScale(boolean enabled) throws IllegalStateException {
		boolean old = isLogScaleEnabled();
		super.setLogScale(enabled);
		fireAxisLogScaleChanged(old, logScaleEnabled);
	}

	private void fireAxisLogScaleChanged(boolean old, boolean logScale) {

		if (old == logScale)
			return;

		for (IAxisListener listener : listeners)
			listener.axisLogScaleChanged(this, old, logScale);
	}

	/**
	 * Field used to remember the previous zoom type used
	 */
	private ZoomType previousZoomType = ZoomType.NONE;

	/**
	 * Listener to mouse events, performs panning and some zooms Is very similar
	 * to the PlotMouseListener, but unclear how easy/useful it would be to base
	 * them on the same code.
	 */
	class AxisMouseListener extends MouseMotionListener.Stub implements MouseListener {
		private SaveStateCommand command;

		@Override
		public void mousePressed(final MouseEvent me) {
			// Only react to 'main' mouse button, only react to 'real' zoom
			if ((me.button != PlotArea.BUTTON1 || !isValidZoomType(zoomType)) && me.button != PlotArea.BUTTON2)
				return;
			// Remember last used zoomtype
			previousZoomType = zoomType;
			// if mousewheel is pressed
			if (me.button == PlotArea.BUTTON2) {
				zoomType = ZoomType.PANNING;
			}
			armed = true;
			// get start position
			switch (zoomType) {
			case RUBBERBAND_ZOOM:
			case DYNAMIC_ZOOM:
				if (isHorizontal())
					start = new Point(me.getLocation().x, bounds.y);
				else
					start = new Point(bounds.x, me.getLocation().y);
				end = null;
				break;
			case HORIZONTAL_ZOOM:
				start = new Point(me.getLocation().x, bounds.y);
				end = null;
				break;
			case VERTICAL_ZOOM:
				start = new Point(bounds.x, me.getLocation().y);
				end = null;
				break;
			case PANNING:
				setCursor(grabbing);
				start = me.getLocation();
				end = null;
				startRange = getRange();
				break;
			case ZOOM_IN:
			case ZOOM_IN_HORIZONTALLY:
			case ZOOM_IN_VERTICALLY:
			case ZOOM_OUT:
			case ZOOM_OUT_HORIZONTALLY:
			case ZOOM_OUT_VERTICALLY:
				start = me.getLocation();
				end = new Point();
				// Start timer that will zoom while mouse button is pressed
				Display.getCurrent().timerExec(ZOOM_SPEED, new Runnable() {
					@Override
					public void run() {
						if (!armed)
							return;
						performInOutZoom();
						Display.getCurrent().timerExec(ZOOM_SPEED, this);
					}
				});
				break;
			default:
				break;
			}

			// add command for undo operation
			command = new AxisPanOrZoomCommand(zoomType.getDescription(), Axis.this);
			me.consume();
		}

		@Override
		public void mouseDoubleClicked(final MouseEvent me) { /* Ignored */
		}

		@Override
		public void mouseDragged(final MouseEvent me) {
			if (!armed)
				return;
			switch (zoomType) {
			case RUBBERBAND_ZOOM:
			case DYNAMIC_ZOOM:
				// Treat rubberband zoom on axis like horiz/vert. zoom
				if (isHorizontal())
					end = new Point(me.getLocation().x, bounds.y + bounds.height);
				else
					end = new Point(bounds.x + bounds.width, me.getLocation().y);
				break;
			case HORIZONTAL_ZOOM:
				end = new Point(me.getLocation().x, bounds.y + bounds.height);
				break;
			case VERTICAL_ZOOM:
				end = new Point(bounds.x + bounds.width, me.getLocation().y);
				break;
			case PANNING:
				end = me.getLocation();
				pan();
				break;
			default:
				break;
			}
			Axis.this.repaint();
		}

		@Override
		public void mouseExited(final MouseEvent me) {
			// Treat like releasing the button to stop zoomIn/Out timer
			switch (zoomType) {
			case ZOOM_IN:
			case ZOOM_IN_HORIZONTALLY:
			case ZOOM_IN_VERTICALLY:
			case ZOOM_OUT:
			case ZOOM_OUT_HORIZONTALLY:
			case ZOOM_OUT_VERTICALLY:
				mouseReleased(me);
			default:
			}
		}

		@Override
		public void mouseReleased(final MouseEvent me) {
			if (!armed)
				return;
			armed = false;
			if (zoomType == ZoomType.PANNING)
				setCursor(zoomType.getCursorOnAxis(isHorizontal()));
			if (end == null || start == null || command == null)
				return;

			switch (zoomType) {
			case RUBBERBAND_ZOOM:
			case DYNAMIC_ZOOM:
			case HORIZONTAL_ZOOM:
			case VERTICAL_ZOOM:
				performStartEndZoom();
				break;
			case PANNING:
				pan();
				break;
			case ZOOM_IN:
			case ZOOM_IN_HORIZONTALLY:
			case ZOOM_IN_VERTICALLY:
			case ZOOM_OUT:
			case ZOOM_OUT_HORIZONTALLY:
			case ZOOM_OUT_VERTICALLY:
				performInOutZoom();
				break;
			default:
				break;
			}
			// mousewheel is pressed and last zoom type was not panning, we set
			// the zoomtype to the previous state.
			if (me.button == PlotArea.BUTTON2 && previousZoomType != ZoomType.PANNING) {
				setZoomType(previousZoomType);
			}
			command.saveState();
			xyGraph.getOperationsManager().addCommand(command);
			command = null;
			start = null;
			end = null;
		}

		/** Perform the zoom to mouse start/end */
		private void performStartEndZoom() {
			final double t1 = getPositionValue(isHorizontal() ? start.x : start.y, false);
			final double t2 = getPositionValue(isHorizontal() ? end.x : end.y, false);
			// Properly set the range given the values of t1 and t2: if the
			// maximum value of the range is smaller than the minimum,
			// accordingly set the min and max given the values of t1 and t2 and
			// vice versa.
			boolean isMinBigger = getRange().isMinBigger();
			if (isMinBigger == (t1 > t2)) {
				setRange(t1, t2);
			} else {
				setRange(t2, t1);
			}
		}

		/** Perform the in or out zoom according to zoomType */
		private void performInOutZoom() {
			final int pixel_pos = isHorizontal() ? start.x : start.y;
			final double center = getPositionValue(pixel_pos, false);
			switch (zoomType) {
			case ZOOM_IN:
				zoomInOut(center, ZOOM_RATIO);
				break;
			case ZOOM_IN_HORIZONTALLY:
				zoomInOut(center, ZOOM_RATIO);
				break;
			case ZOOM_IN_VERTICALLY:
				zoomInOut(center, ZOOM_RATIO);
				break;
			case ZOOM_OUT:
				zoomInOut(center, -ZOOM_RATIO);
				break;
			case ZOOM_OUT_HORIZONTALLY:
				zoomInOut(center, -ZOOM_RATIO);
				break;
			case ZOOM_OUT_VERTICALLY:
				zoomInOut(center, -ZOOM_RATIO);
				break;
			default: // NOP
			}
		}
	}
}