Re: st: New version of -spmap- available from SSC

[Maurizio Pisati <maurizio.pisati@unimib.it>]

Dear Volodymyr,
computing power apart, the speed basically 
depends on the number and complexity of spatial 
objects you ask -spmap- to draw. In your specific 
case, drawing 670 polygons is a relatively 
time-consuming task, especially if each polygon 
is represented in a very detailed manner, i.e., 
is made up of a lot of nodes. In such cases, 
speed can be substantially increased if you use a 
"simplified" version of your map, namely one in 
which the constituent polygons are - so to speak 
- "smoothed" (for instance, by applying the 
Douglas-Peucker line simplification algorithm or one of its variants).
Best,
Maurizio



Reference
Douglas, D.H. and T.K. Peucker. 1973. "Algorithms 
for the reduction of the number of 
points-required to represent a line or its caricature", The Canadian
Cartographer 10: 112�122.





At 01.07 15/03/2008, you wrote:

> Thank you for a great program!
>
> I have used it since last Summer to map 670 regions in Ukraine. It was
> my impression that it works a bit slow. What does the speed depend on?
>
> Volodymyr.

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