Implement faster display of structures and isodose data in the 2D View

[GoogleCodeExporter]

Currently the structure display in the 2D View is rather slow. This can be 
improved by caching of the structure data.

One way to improve this would be to cache the data after the user clicks on the 
structure checkbox but before each structure is displayed. The existing 
progress bar function in guiutil.py can be reused for this.

Another way could be to silently load the data in another thread without the 
progress bar function.

Original issue reported on code.google.com by bastula on 18 Jun 2010 at 2:37

[GoogleCodeExporter]

This could also be applied to isodose data as well, since it is static just 
like structure data.

The only thing that shouldn't be cached is the image data, since it can change 
dynamically with window/level control.

Original comment by bastula on 21 Jun 2010 at 1:02

• Changed title: Implement faster display of structures and isodose data in the 2D View

[GoogleCodeExporter]

Original comment by bastula on 12 Nov 2010 at 4:25

• Added labels: Milestone-Release1.0