[udig-devel] Re: performance when creating polygons

[Jesse Eichar <jeichar@xxxxxxxxxxxxxxx>]

There are a few things here:

1.  Each time you move the mouse the entire viewport is redrawn to a background buffer then draw to the screen.  This takes a lot of CPU.  I've had plans on allowing just parts of the viewport to be updated but it is a complicated procedure to calculate what needs to be updated.  Each Draw command is supposed to have a area that needs to be refreshed for them.  I'm not sure all of them are there.  

That is probably the biggest issue right now.  I have never had time to finish work on the Edit tools performance tuning is one of the things I really want to get at.  Hopefully I'll find some time soon.

Jesse

On Sep 6, 2007, at 1:17 AM, tony.roth@xxxxxx wrote:

Hi Jesse,

a second mail not via the list due to file attachement.

 

The screenshot shows the performance of my computer (pentium 4 HT with 3.4GHz and 2GB RAM) while creating a polygon.

 

I added red and yellow rectangles to the cpu statistics.

 

The red one contains the time I draw the last polygon (the one with 9 vertices) on the map. I did it quite slowly and it lasts about 18 seconds.

The yellow ones contain time where I just moved the mouse over the map. The background noise (all other running processes where more or less sleeping) is not more than 2% load, so all this load is just produced by udig.

 

I won't nudge about that but I think it's quite a lot load which is produced. The pentium 4 is not the newest one but it's a quite fast computer.

 

When creating a new polygon each vertex creation is symbolized with a little animation where a circle shrinks to the square which symbolizes the vertex. This animation is sometimes stuttering and not fluid due to the load.

 

tony roth

<performance_rc11.png>