X-Git-Url: http://gitweb.fperrin.net/?p=GpsPrune.git;a=blobdiff_plain;f=src%2Ftim%2Fprune%2Fgui%2Fmap%2FScaleBar.java;fp=src%2Ftim%2Fprune%2Fgui%2Fmap%2FScaleBar.java;h=37e12b65bfbbdebb76216869232d4f3089ee35f3;hp=0000000000000000000000000000000000000000;hb=ce6f2161b8596f7018d6a76bff79bc9e571f35fd;hpb=2d8cb72e84d5cc1089ce77baf1e34ea3ea2f8465

diff --git a/src/tim/prune/gui/map/ScaleBar.java b/src/tim/prune/gui/map/ScaleBar.java
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+++ b/src/tim/prune/gui/map/ScaleBar.java
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+package tim.prune.gui.map;
+
+import java.awt.Color;
+import java.awt.Dimension;
+import java.awt.Graphics;
+import javax.swing.JPanel;
+
+import tim.prune.I18nManager;
+import tim.prune.config.ColourScheme;
+import tim.prune.config.Config;
+import tim.prune.data.Unit;
+
+/**
+ * Class to show a scale bar on the main map of GpsPrune
+ */
+public class ScaleBar extends JPanel
+{
+	/** zoom level */
+	private int _zoomLevel = -1;
+	/** y position */
+	private double _yPos = 0.0;
+
+	// Dimensions
+	/** Offset from left side in pixels */
+	private static final int LEFT_OFFSET = 20;
+	/** Offset from top in pixels */
+	private static final int Y_OFFSET = 10;
+	/** Tick height in pixels */
+	private static final int TICK_HEIGHT = 5;
+	/** Margin between bar and end text in pixels */
+	private static final int MARGIN_WIDTH = 8;
+
+	/** scales for each zoom level */
+	private static final int[] _scales = {10000, 5000, 2000, 2000, 1000, 500, 200, 100,
+		50, 20, 10, 5, 2, 2, 1,
+		-2, -5, -10, -20, -50, -100, -200};
+	/** pixel counts for each zoom level (metric) */
+	private static final double[] _metricPixels = {64, 64, 51, 102, 102, 102, 81, 81,
+		81, 65, 65, 65, 52, 105, 105,
+		105, 83, 83, 83, 67, 67, 67};
+
+
+	/**
+	 * Constructor
+	 */
+	public ScaleBar()
+	{
+		super();
+		setOpaque(false);
+		setPreferredSize(new Dimension(100, 20));
+	}
+
+	/**
+	 * Paint method to override display
+	 * @param inG graphics object
+	 */
+	public void paint(Graphics inG)
+	{
+		super.paint(inG);
+		if (_zoomLevel > -1)
+		{
+			try {
+				final double distScaleFactor = Config.getUnitSet().getDistanceUnit().getMultFactorFromStd();
+				double drightSide = LEFT_OFFSET + _metricPixels[_zoomLevel] / 1000.0 / distScaleFactor;
+				int scale = _scales[_zoomLevel];
+
+				// work out cos(latitude) from y position, and apply to scale
+				final double angle = Math.PI * (1 - 2*_yPos);
+				final double lat = Math.atan(Math.sinh(angle));
+				final double cosLat = Math.cos(lat);
+				int rightSide = (int) (drightSide / cosLat);
+				// Adjust if scale is too large
+				while (rightSide > 300)
+				{
+					rightSide /= 2;
+					scale /= 2;
+					// Abort if scale is now less than 1 unit (shouldn't ever be)
+					if (scale < 1) {return;}
+				}
+				// Abort if scale is negative (around poles)
+				if (rightSide < 1) {return;}
+
+				// Determine colours to use
+				Color barColour = Config.getColourScheme().getColour(ColourScheme.IDX_TEXT);
+				Color blankColour = new Color(255-barColour.getRed(), 255-barColour.getGreen(), 255-barColour.getBlue());
+				// Should this blank colour be set to saturation zero?
+				// Draw blank bars behind
+				inG.setColor(blankColour);
+				inG.drawLine(LEFT_OFFSET, Y_OFFSET-1, rightSide+2, Y_OFFSET-1);
+				inG.drawLine(LEFT_OFFSET, Y_OFFSET+2, rightSide+2, Y_OFFSET+2);
+				inG.drawLine(LEFT_OFFSET-1, Y_OFFSET+2, LEFT_OFFSET-1, Y_OFFSET-TICK_HEIGHT);
+				inG.drawLine(LEFT_OFFSET+2, Y_OFFSET+2, LEFT_OFFSET+2, Y_OFFSET-TICK_HEIGHT);
+				inG.drawLine(rightSide-1, Y_OFFSET+2, rightSide-1, Y_OFFSET-TICK_HEIGHT);
+				inG.drawLine(rightSide+2, Y_OFFSET+2, rightSide+2, Y_OFFSET-TICK_HEIGHT);
+				// horizontal
+				inG.setColor(barColour);
+				inG.drawLine(LEFT_OFFSET, Y_OFFSET, rightSide, Y_OFFSET);
+				inG.drawLine(LEFT_OFFSET, Y_OFFSET+1, rightSide, Y_OFFSET+1);
+				// 0 tick
+				inG.drawLine(LEFT_OFFSET, Y_OFFSET, LEFT_OFFSET, Y_OFFSET-TICK_HEIGHT);
+				inG.drawLine(LEFT_OFFSET+1, Y_OFFSET, LEFT_OFFSET+1, Y_OFFSET-TICK_HEIGHT);
+				// end tick
+				inG.drawLine(rightSide, Y_OFFSET+1, rightSide, Y_OFFSET-TICK_HEIGHT);
+				inG.drawLine(rightSide+1, Y_OFFSET+1, rightSide+1, Y_OFFSET-TICK_HEIGHT);
+				// text
+				String text = getScaleText(scale, Config.getUnitSet().getDistanceUnit());
+				inG.setColor(blankColour);
+				inG.drawString(text, rightSide+MARGIN_WIDTH-1, Y_OFFSET);
+				inG.drawString(text, rightSide+MARGIN_WIDTH+1, Y_OFFSET);
+				inG.drawString(text, rightSide+MARGIN_WIDTH, Y_OFFSET-1);
+				inG.drawString(text, rightSide+MARGIN_WIDTH, Y_OFFSET+1);
+				inG.setColor(barColour);
+				inG.drawString(text, rightSide+MARGIN_WIDTH, Y_OFFSET);
+			}
+			catch (ArrayIndexOutOfBoundsException ai) {}
+		}
+	}
+
+	/**
+	 * Get the scale text for the given scale
+	 * @param inScale scale number
+	 * @param inDistUnit distance unit
+	 * @return scale text as string
+	 */
+	private static String getScaleText(int inScale, Unit inDistUnit)
+	{
+		if (inScale > 0) {
+			// Positive scale means km or miles
+			return "" + inScale	+ " " +
+				I18nManager.getText(inDistUnit.getShortnameKey());
+		}
+		// negative scale means a fraction
+		return "" + (-1.0 / inScale) + " " + I18nManager.getText(inDistUnit.getShortnameKey());
+		// might be nice to say 100m instead of 0.1km, 275ft instead of 0.2miles, etc - need to be done by Unit itself?
+	}
+
+	/**
+	 * Update the scale level
+	 * @param inZoom new zoom level
+	 * @param inYPos y position, where 0 is north pole, 1 is south pole
+	 */
+	public void updateScale(int inZoom, double inYPos)
+	{
+		_zoomLevel = inZoom;
+		_yPos = inYPos;
+	}
+}