public RamachandranPlot(Canvas parent) {

		m_parent = parent;

		// configure the plot
		Range axisRange = new Range(MIN_RANGE, MAX_RANGE);
		m_plot = new XYGraph();
		//		m_plot.setTitle(DEFAULT_TITLE);
		m_plot.setShowLegend(false);
		m_plot.setTransparent(true);
		m_plot.primaryXAxis.setTitle(PHI);
		m_plot.primaryYAxis.setTitle(PSI);
		m_plot.primaryXAxis.setMinorTicksVisible(false);
		m_plot.primaryYAxis.setMinorTicksVisible(false);
		m_plot.primaryXAxis.setRange(axisRange);
		m_plot.primaryYAxis.setRange(axisRange);

		// configure the heat map
		int dataLength = MAX_RANGE - MIN_RANGE;
		m_heatmap = new IntensityGraphFigure(false);
		m_heatmap.setMax(INTENSITY_MAX);
		m_heatmap.getXAxis().setTitle("");
		m_heatmap.getYAxis().setTitle("");
		m_heatmap.getXAxis().setMinorTicksVisible(false);
		m_heatmap.getYAxis().setMinorTicksVisible(false);
		m_heatmap.getXAxis().setRange(axisRange);
		m_heatmap.getYAxis().setRange(axisRange);
		m_heatmap.setColorMap(new ColorMap( PredefinedColorMap.Cool, true,
				true ));
		m_heatmap.setShowRamp(false);
		m_heatmap.setDataHeight(dataLength);
		m_heatmap.setDataWidth(dataLength);

		// load data... (not shown)

		// overlay the graphs
		org.eclipse.swt.graphics.Rectangle client = m_parent.getClientArea();
		Rectangle constraint = new Rectangle(0, 0, client.width, 
				client.height);
		m_container = new Figure();
		m_container.setLayoutManager(new XYLayout());
		m_container.add(m_heatmap, constraint);
		m_container.add(m_plot, constraint);

		// put graph in canvas
		m_lws = new LightweightSystem(m_parent);
		m_lws.setContents(m_container);
	}