Rendering of dashed lines is very slow

[Bug Importer]

If display mode is set to 'Normal' then rendering of dashed lines is
extremely slow. I have created SVG file with about 60 lines. If I zoom in
or zoom out then repainting of whole window takes about 5 seconds.

I'm using version 0.45 pre1 on Windows XP.

[Mercury (mercury13)]

It becomes slow in a leap. 50 lines OK, 55 - too bad.
Maybe, connected with 167525?

[prkos (prkos)]

Confirmed on WinXP build from 6th Jan

I tested using only 6 lines and I could see the difference in rendering speed between solid stroke and dashed. It gets slower as more lines are added.

[prkos (prkos)]

It also matters which dashes you choose. The slowest seem to be those with most dashes/gaps - short dashes with short gaps (the bottom 3 for example).

Also if you choose the bottom one there are problems when you zoom in a lot, it takes a lot of time for everything and the dashes and gaps are blurred.

[jazzynico (jazzynico)]

Reproduced on Ubuntu 10.10, Inkscape 0.48.0-1ubuntu1.2.
Not reproduced (now very fast) with trunk revision 10444 (new Cairo renderer).