/**
* Draws the Legend for the scatter plot
*
* @param g {@link Graphics}
*/
private void drawLegend(Graphics g) {
// set the color of the legend rectangle
g.setColor(LEGEND_BACKGROUND);
int lineHeight = g.getFontMetrics().getHeight() + 2; // height of a legend line
// draw the legend rectangle
g.fillRect(
getWidth() - legendWidth - LENGEND_PAD - (LEGEND_INSET * 2),
LENGEND_PAD,
legendWidth + (LEGEND_INSET * 2),
((data.size() + 2) * lineHeight) + (LEGEND_INSET * 2));
g.setColor(Colors.BLACK);
g.drawRect(
getWidth() - legendWidth - LENGEND_PAD - (LEGEND_INSET * 2),
LENGEND_PAD,
legendWidth + (LEGEND_INSET * 2),
((data.size() + 2) * lineHeight) + (LEGEND_INSET * 2));
// search the position where to start the text of the legend
Point p =
new Point(
getWidth() - legendWidth - LENGEND_PAD - LEGEND_INSET,
LENGEND_PAD + LEGEND_INSET + g.getFontMetrics().getHeight());
// draw the axis names
g.drawString(X_AXIS_PREFIX + xAxis.getName(), p.x, p.y); // draw X-Axis legend
g.drawString(Y_AXIS_PREFIX + yAxis.getName(), p.x, p.y + lineHeight); // draw Y-Axis legend
// draw graph name legend
for (int i = 0; i < data.size(); i++) {
Color graphColor = data.get(i).getColor();
String graphName = data.get(i).getName();
g.setColor(graphColor);
int yLine = p.y + ((i + 2) * lineHeight); // y position of the current line
g.drawLine(p.x, yLine - 5, p.x + 25, yLine - 5); // draw a line with the color of the graph
g.setColor(Colors.BLACK);
g.drawString(graphName, p.x + 30, yLine); // draw the name of the graph
}
}
/**
* Method to plot the data points as a curve chart
*
* @param g (Graphics)
*/
private void drawCurveGraphics(Graphics g) {
for (ScatterPlotData currentScatterPlot : data) {
g.setColor(currentScatterPlot.getColor());
for (int j = 0; j < (currentScatterPlot.getData().length - 1); j++) {
Point current =
new Point(
getTranslatedPoint(
currentScatterPlot.getData()[j][0], currentScatterPlot.getData()[j][1]));
Point nexttonext =
new Point(
getTranslatedPoint(
currentScatterPlot.getData()[j + 1][0],
currentScatterPlot.getData()[j + 1][1]));
g.drawLine(current.x, current.y, nexttonext.x, nexttonext.y);
if ((currentScatterPlot.getData()[j][0] < xAxis.getMin())
|| (currentScatterPlot.getData()[j][0] > xAxis.getMax())
|| (currentScatterPlot.getData()[j + 1][1] <= yAxis.getMax())) {
// we erase the part of the line that is not in the chart area
// this means that the curve needs to be drawn before the axis and ticks and legend
g.setColor(getBackground());
g.fillRect(0, 0, getWidth(), PAD);
g.fillRect(0, getHeight() - PAD, getWidth(), PAD);
g.setColor(currentScatterPlot.getColor());
}
}
}
}
/**
* Method to translate the coordinates of the data point to the point on screen
*
* @param x x component of a data point
* @param y y component of a data point
* @return Point
*/
private Point getTranslatedPoint(double x, double y) {
Point translatedPoint = new Point();
int realWidth = getWidth() - (2 * PAD);
int realHeight = getHeight() - (2 * PAD);
Rectangle clip = new Rectangle(PAD, PAD, realWidth, realHeight);
translatedPoint.x = xAxis.dataValueToScreenPosition(x, clip);
translatedPoint.y = yAxis.dataValueToScreenPosition(y, clip);
return translatedPoint;
}
/** @return the width of the legend text in pixels */
private int computeLegendWidth() {
FontMetrics fm = getFontMetrics(getFont());
int legendWidth = fm.stringWidth(X_AXIS_PREFIX + xAxis.getName());
legendWidth = Math.max(legendWidth, fm.stringWidth(Y_AXIS_PREFIX + yAxis.getName()));
for (ScatterPlotData currentPlot : data) {
if (data != null) {
legendWidth = Math.max(legendWidth, fm.stringWidth(currentPlot.getName()) + 30);
}
}
return legendWidth;
}
/**
* Method to plot the data points as a point chart
*
* @param g (Graphics)
*/
private void drawPointGraphics(Graphics g) {
for (ScatterPlotData currentScatterPlot : data) {
g.setColor(currentScatterPlot.getColor());
for (int j = 0; j < (currentScatterPlot.getData().length - 1); j++) {
Point current =
new Point(
getTranslatedPoint(
currentScatterPlot.getData()[j][0], currentScatterPlot.getData()[j][1]));
Point next =
new Point(
getTranslatedPoint(
currentScatterPlot.getData()[j + 1][0], currentScatterPlot.getData()[j][1]));
if ((currentScatterPlot.getData()[j][0] >= xAxis.getMin())
&& (currentScatterPlot.getData()[j][0] <= xAxis.getMax())
&& (currentScatterPlot.getData()[j][1] >= yAxis.getMin())
&& (currentScatterPlot.getData()[j][1] <= yAxis.getMax())) {
g.drawLine(current.x, current.y, next.x, next.y);
}
}
}
}
/**
* @param screenPoint {@link Point} of a screen position
* @return original data Point corresponding to the specified screen position
*/
private Point2D getDataPoint(Point screenPoint) {
Point2D.Double retPoint = new Point2D.Double();
retPoint.x =
(((screenPoint.x - PAD) * (xAxis.getMax() - xAxis.getMin())) / (getWidth() - (2 * PAD)))
+ xAxis.getMin();
retPoint.y =
(-1
* ((((screenPoint.y - getHeight()) + PAD) * (yAxis.getMax() - yAxis.getMin()))
/ (getHeight() - (2 * PAD))))
+ yAxis.getMin();
return retPoint;
}
@Override
public void paint(Graphics g) {
super.paint(g);
// set where inside the dialog, the chart needs to be drawn
Rectangle clip = new Rectangle(PAD, PAD, getWidth() - (2 * PAD), getHeight() - (2 * PAD));
// draw the background of the chart
drawChartBackground(g, clip);
// set the position of the axis in case they moved
if (yAxis.isLogScale()) {
xAxis.setPosition(yAxis.dataValueToScreenPosition(1, clip));
} else {
xAxis.setPosition(yAxis.dataValueToScreenPosition(0, clip));
}
if (xAxis.isLogScale()) {
yAxis.setPosition(xAxis.dataValueToScreenPosition(1, clip));
} else {
yAxis.setPosition(xAxis.dataValueToScreenPosition(0, clip));
}
// draw the grid
xAxis.drawGrid(g, clip);
yAxis.drawGrid(g, clip);
// draw the curve
drawGraphics(g, clip, chartType);
// draw the axis
xAxis.drawAxis(g, clip);
yAxis.drawAxis(g, clip);
// draw minor units
xAxis.drawMinorUnit(g, clip);
yAxis.drawMinorUnit(g, clip);
// draw major units
xAxis.drawMajorUnit(g, clip);
yAxis.drawMajorUnit(g, clip);
// draw the chart legend
drawLegend(g);
}
