Re: [udig-devel] ApplicationGIS drawMap example

[Jody Garnett <jody.garnett@xxxxxxxxx>]

Okay in discussion on IRC the actual request turned out a bit different.

The idea is to delay a layer refresh; until the entire image is ready. The idea is to update a style; and not watch the screen draw the new features in. Since the rendering system is listening to the renderer turn over and issue events; perhaps we could configure the renderer to only issue an event when it is "done" ?

Jesse you are a bit more familiar with the rendering system at this level; could we, place something on the style blackboard and then modify the BasicFeatureRenderer to issue less events in this case?

Jody

On 19/01/2011, at 2:21 PM, Jody Garnett wrote:

Here is a cut&paste of calling AppplicationGIS.drawMap (it comes from the box preview code used in printing):

    BufferedImage preview;

    State current;

    public void createPreview( Graphics2D graphics, final IProgressMonitor monitor ) {

Dimension size = getBox().getSize();

        try {

            if (map != null) {

                preview = new BufferedImage(size.width, size.height, BufferedImage.TYPE_INT_ARGB);

                Graphics2D g = preview.createGraphics();

                try {

                    ApplicationGIS.drawMap(new DrawMapParameter(g, new java.awt.Dimension(

                            size.width, size.height), this.map, monitor));

                } finally {

                    g.dispose();

                }

                current = new State(map.getViewportModel(), getBox().getSize());

                graphics.drawImage(preview, 0, 0, size.width, size.height, 0, 0,

                        preview.getWidth(), preview.getHeight(), null);

            }

        } catch (Exception e) {

            PrintingModelPlugin.log("", e); //$NON-NLS-1$

            String message = "Error rendering Map:  " + e.getMessage(); //$NON-NLS-1$

            drawErrorMessage(graphics, message);

        }

        setDirty(false);

    }

You could do something similar to get an image; for use in a View.

To make a single threaded renderer we could use this code as an example; MapEditor uses the "widget" MapViewer to get the job done; perhaps we can teach it to be single threaded using something similar to ApplicationGIS.drawMap.

Out of curiosity why are you interested in a single threaded renderer?

Jody