+/*
+ * Copyright 2006 the original author or authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.wamblee.gpx;
+
+import java.awt.Graphics2D;
+import java.awt.Image;
+import java.awt.geom.Rectangle2D;
+
+import org.jfree.chart.axis.ValueAxis;
+import org.jfree.chart.plot.XYPlot;
+import org.jfree.chart.renderer.xy.XYItemRenderer;
+import org.jfree.data.xy.XYDataset;
+
+/**
+ *
+ */
+public class ZoomableBackgroundXYPlot extends XYPlot {
+
+ /*
+ * Initial domain axis.
+ */
+ private double _x1 = 1.0;
+ private double _x2 = -1.0; // _x2 < _x1 initially to make signify uninitialized values.
+
+ /*
+ * Initial range axis.
+ */
+ private double _y1 = 1.0;
+ private double _y2 = -1.0; // _y2 < _y1 initially to make signify uninitialized values.
+
+ public ZoomableBackgroundXYPlot(XYDataset aDataset,
+ ValueAxis aDomainAxis, ValueAxis aRangeAxis, XYItemRenderer aRenderer) {
+ super(aDataset, aDomainAxis, aRangeAxis, aRenderer);
+ }
+
+ /* (non-Javadoc)
+ * @see org.jfree.chart.plot.Plot#drawBackgroundImage(java.awt.Graphics2D, java.awt.geom.Rectangle2D)
+ */
+ @Override
+ protected void drawBackgroundImage(Graphics2D g2, Rectangle2D area) {
+ //System.out.println("--------");
+ //System.out.println("Area: " + area);
+ //System.out.println("Graphics clip: " + g2.getClipBounds());
+ //System.out.println("Domain axis: " + getDomainAxis().getLowerBound() + " " +
+ // getDomainAxis().getUpperBound());
+
+ // Get the current domain axis bounds
+ double y1 = getDomainAxis().getLowerBound();
+ double y2 = getDomainAxis().getUpperBound();
+ double x1 = getRangeAxis().getLowerBound();
+ double x2 = getRangeAxis().getUpperBound();
+
+ if ( _x2 < _x1 ) {
+ // initial domain axis bounds
+ _y1 = y1;
+ _y2 = y2;
+ _x1 = x1;
+ _x2 = x2;
+ }
+
+ Image background = getBackgroundImage();
+ int width = background.getWidth(null);
+ int height = background.getHeight(null);
+
+ // Determine the part of the image to be drawn on the screen based on the scaling
+ // of the domain axes.
+ int imageX1 = (int)Math.round(1 + (x1 - _x1)*(width-1)/(_x2 - _x1));
+ int imageX2 = (int)Math.round(1 + (x2 - _x1)*(width-1)/(_x2 - _x1));
+ // Note: y-axis of image goes from bottom to top.
+ int imageY2 = (int)Math.round(height + (y1 - _y1)*(1-height)/(_y2 - _y1));
+ int imageY1 = (int)Math.round(height + (y2 - _y1)*(1-height)/(_y2 - _y1));
+
+ // Draw the correct part of the image on the screen.
+ g2.drawImage(background, (int)area.getMinX(), (int)area.getMinY(), (int)area.getMaxX(), (int)area.getMaxY(),
+ imageX1, imageY1, imageX2, imageY2, null);
+
+ // System.out.println("========");
+ }
+
+}