Canvas widget getting very slow
[email protected] Wed, 14 Jan 2009 15:46:01 +0100 (CET)
| Newsgroups | gmane.comp.lang.perl.tk |
|---|---|
| Message-ID | <1588373156.243713.1231944361586.JavaMail.webmailer@webmail.1and1.com> |
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Hi all,
I'm using a Canvas widget to emulate a raster graphics display.
I'm setting pixels by drawing lines of length 1.
Unfortunately the Canvas gets slow exponentially when
a lot of such line items are added. If there are more than
about 8000 it's getting very slow, and above 12000 it's getting
extremely slow...
If I wait until everything's drawn and then delete everything and
draw again, it is a bit faster. Maybe this points to an influence of
some cache.
Does somebody know of a solution to this. Or is there a better
widget to emulate a raster graphics display?
Thanks & kind regards,
Gerhard
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<P><BR><SPAN id=3Deditor_signature><FONT face=3DVerdana color=3D#000000 siz=
e=3D2>Hi all,</FONT></SPAN></P><SPAN><FONT face=3DVerdana color=3D#000000 s=
ize=3D2>
<P><BR>I'm using a Canvas widget to emulate a raster graphics display.<BR>I=
'm setting pixels by drawing lines of length 1.</P>
<P><BR>Unfortunately the Canvas gets slow exponentially when<BR>a lot of su=
ch line items are added. If there are more than<BR>about 8000 it's getting =
very slow, and above 12000 it's getting<BR>extremely slow...</P>
<P><BR>If I wait until everything's drawn and then delete everything and<BR=
>draw again, it is a bit faster. Maybe this points to an influence of<BR>so=
me cache.</P>
<P><BR>Does somebody know of a solution to this. Or is there a better<BR>wi=
dget to emulate a raster graphics display?</P>
<P><BR>Thanks & kind regards,<BR>Gerhard</FONT></SPAN></P></body></html=
>
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