allow graph lines to have a line size of zero to be able to hide them

uk/ac/sanger/artemis/components/BasePlot.java

@@ -767,6 +767,8 @@ public class BasePlot extends Plot
       if(i < lines.length)
       {
         g.setColor(lines[i].getLineColour());
+        if(lines[i].getStroke() == null)
+          continue;
         ((Graphics2D)g).setStroke(lines[i].getStroke());
       }
       else

uk/ac/sanger/artemis/plot/LineAttributes.java

@@ -67,7 +67,7 @@ public class LineAttributes
   private BasicStroke stroke;
   
   private static float dotDash[] = {10.f, 5.f, 3.f, 5.f};
-  private static float dash[] = {10.f};
+  private static float dash[] = {5.f};
   
   private static BasicStroke style1 = 
       new BasicStroke(1.f);
@@ -131,6 +131,8 @@ public class LineAttributes
    */
   private static int getStyleIndex(BasicStroke stroke)
   {
+    if(stroke == null)
+      stroke = style1;
     float myDash[] = stroke.getDashArray();
     if(myDash != null && 
        myDash.length == dotDash.length)
@@ -304,8 +306,13 @@ public class LineAttributes
       panel.add(butt, c);
       
       // line style
-      final JSlider slider = new JSlider(1, 10, 
-          (int)lines[colourNumber].getStroke().getLineWidth());
+      final int lineWidth;
+      if(lines[colourNumber].getStroke() == null)
+        lineWidth = 0;
+      else
+        lineWidth = (int)lines[colourNumber].getStroke().getLineWidth();
+      
+      final JSlider slider = new JSlider(0, 10, lineWidth);
       Integer index[] = new Integer[STROKES.length];
       for(int j=0; j<index.length; j++)
         index[j] = j;
@@ -331,6 +338,8 @@ public class LineAttributes
       {
         public void stateChanged(ChangeEvent e)
         {
+          thislines[colourNumber].setStroke(
+              STROKES[lineStyle.getSelectedIndex()]);
           setLineSize(plot, slider, thislines, colourNumber);
         }
       });
@@ -368,12 +377,17 @@ public class LineAttributes
   
   private static void setLineSize(Plot plot, JSlider slider,
                            LineAttributes[] thislines, int number)
+  {
+    if(slider.getValue() == 0.f)
+      thislines[number].setStroke(null);
+    else
     {
       BasicStroke oldStroke = thislines[number].getStroke();
       BasicStroke newStroke = new BasicStroke(slider.getValue(),
         BasicStroke.CAP_SQUARE, BasicStroke.JOIN_MITER, 
         1.f, oldStroke.getDashArray(), 0.f);
       thislines[number].setStroke(newStroke);
+    }
     plot.repaint();
   }
 }