Bug 363281

Description Andreas Mayer 2011-11-09 05:51:06 EST

Build Identifier: M20110909-1335

CopyToImageAction (File > Save As Image File ...) fails with an IllegalArgumentException("negative width") from java.awt.BasicStroke, if any figure in the diagram has a negative line width (see also bug #243187). 

java.lang.IllegalArgumentException: negative width
    at java.awt.BasicStroke.<init>(BasicStroke.java:192)
    at org.eclipse.gmf.runtime.draw2d.ui.render.awt.internal.graphics.GraphicsToGraphics2DAdaptor.createStroke(GraphicsToGraphics2DAdaptor.java:1543)
    at org.eclipse.gmf.runtime.draw2d.ui.render.awt.internal.graphics.GraphicsToGraphics2DAdaptor.drawPolygon(GraphicsToGraphics2DAdaptor.java:633)
    at org.eclipse.draw2d.Graphics.drawPolygon(Graphics.java:293)
    at org.eclipse.gmf.runtime.draw2d.ui.internal.graphics.ScaledGraphics.drawPolygon(ScaledGraphics.java:356)
    at org.eclipse.draw2d.Polygon.outlineShape(Polygon.java:64)
    at org.eclipse.draw2d.Shape.paintOutline(Shape.java:175)
    at org.eclipse.draw2d.Shape.paintFigure(Shape.java:147)
    at org.eclipse.draw2d.Figure.paint(Figure.java:1115)
    at org.eclipse.draw2d.Figure.paintChildren(Figure.java:1167)
    at org.eclipse.draw2d.Figure.paintClientArea(Figure.java:1202)
    at org.eclipse.draw2d.Figure.paint(Figure.java:1117)
    at org.eclipse.gmf.runtime.diagram.ui.render.clipboard.DiagramGenerator.paintFigure(DiagramGenerator.java:373)
    at org.eclipse.gmf.runtime.diagram.ui.render.clipboard.DiagramGenerator.renderToGraphics(DiagramGenerator.java:237)
    at org.eclipse.gmf.runtime.diagram.ui.render.clipboard.DiagramGenerator.createSWTImageDescriptorForParts(DiagramGenerator.java:721)
    at org.eclipse.gmf.runtime.diagram.ui.render.util.CopyToImageUtil.copyToImage(CopyToImageUtil.java:376)
    at org.eclipse.gmf.runtime.diagram.ui.render.util.CopyToImageUtil.copyToImage(CopyToImageUtil.java:305)
    at org.eclipse.gmf.runtime.diagram.ui.render.actions.CopyToImageAction$1.run(CopyToImageAction.java:260)
    at org.eclipse.jface.operation.ModalContext.runInCurrentThread(ModalContext.java:464)
    at org.eclipse.jface.operation.ModalContext.run(ModalContext.java:372)
    at org.eclipse.jface.dialogs.ProgressMonitorDialog.run(ProgressMonitorDialog.java:507)
    at org.eclipse.gmf.runtime.diagram.ui.render.actions.CopyToImageAction.runCopyToImageUI(CopyToImageAction.java:170)
    [...]

Troubleshooting is difficult here, because the operation fails completely and the exception provides no hint at the offending figure. The Javadocs of Graphics don't specify a behaviour for negative line widths, but under Windows, lines with a negative width are drawn with a line width of 1. If GraphicsToGraphics2DAdaptor would do the same, then CopyToImageAction could succeed and you would be able to spot the error in the resulting image. Therefore, GraphicsToGraphics2DAdator.createStroke() should be changed as follows:

  /*
-  * SWT paints line width == 0 as if it is == 1, so AWT is synced up with that below.
+  * SWT paints line width <= 0 as if it is == 1, so AWT is synced up with that below.
   */
  stroke =
      new BasicStroke(
-         currentState.lineAttributes.width != 0 ? currentState.lineAttributes.width : 1,
+         currentState.lineAttributes.width > 0 ? currentState.lineAttributes.width : 1,
          awt_cap,
          awt_join,
          currentState.lineAttributes.miterLimit,
          awt_dash,
          currentState.lineAttributes.dashOffset);


Reproducible: Always