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Re: [udig-devel] How do I mark certain places on a map?
You can look in the tutorials for an example of adding annotations to a map, the example code does not do the world 2 screen calculations as that is left as a bonus question during the uDig training course.
Someone asks us this question every two months, if you were interested in sharing your work on the uDig community site I am sure their would be interest from others. 

Jody


Hello!
Using uDIG 1.1 RC4 I want to mark certain places on a map with a symbol, e.g. a pin. How can I do that (programmatically)?
To do so I currently use gif files (small ones showing a pin) and corresponding world files. Depending on the bounding box I calculate the size of the pin (the gif) and specify the values in the world file.
This works fine as long as no changes in the scale are done. Zooming in causes the pins to grow, zooming out the pins shrink. (While this is fine when marking areas this is not nice when you just want to mark a certain place). 

Isn't there a better way to mark one or more places on a map?
Another problem occurred when I used my solution for more than about 40 pins on one map (each pin gif has a size of less than 1 KB): I get a Java Heap Space error!
This happens when I do it from my program (plugin) and it also happens when I use uDIG SDK in Eclipse 3.2.1 without any changes and import the pins using the catalog.
This also happens with less than the 40 pins mentioned above when I add let's say 20 pins, remove them from the project, and add them once again. This results in the same heap space error (indicated in the progress monitor).
I detected that behaviour when I tried to repaint the pins with new values in the worldfile after zooming in; but this error occures also when just adding, removing, and adding again the pins from the catalog with no additional plugins. 

Any hints or help welcome. Thank you.

  Michael

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