Re: [simspark-devel] performance

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<span>Hi Yuan,<br>
<br>
<style type="text/css">blockquote {color: navy !important; background-color: RGB(245,245,245) !important; padding: 0 15 10 15 !important; margin: 15 0 0 0; border-left: #1010ff 2px solid;}  blockquote blockquote {color: maroon !important; background-color: RGB(235,235,235) !important; border-left-color:maroon !important}  blockquote blockquote blockquote {color: green !important; background-color: RGB(225,225,225) !important; border-left-color:teal !important}  blockquote blockquote blockquote blockquote {color: purple !important; background-color: RGB(215,215,215) !important; border-left-color: purple !important}  blockquote blockquote blockquote blockquote blockquote {color: teal !important; background-color: RGB(205,205,205) !important; border-left-color: green !important}</style><i><b>"Yuan
Xu" <a class="moz-txt-link-rfc2396E" href="mailto:xuy...@gm...">&lt;xuy...@gm...&gt;</a></b></i> wrote on 01/28/2008 07:53:01 AM:</span><br>
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  <pre wrap="">Hi all,
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    <pre wrap="">Next weekend I'll try to work more on these issues, and probably until then
will know the answer of your 4th question.

4) What's the reason for stepping in discreet steps in SimulationServer::Step()?
Will it change anything with ODE?
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Yes, dWorldStep(20ms)+dWorldStep(20ms) != dWorldStep(40ms).
Because, the collision detection is missing in dWorldStep(40ms).
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Thanks. But there is a problem (I think), it'll be OK if we are
occasionally forced to do more than one step in one cycle, but if it
happens usually which means that the server is unable to finish a
single step in the desired time (which is the current situation I
think), the number of required steps will grow exponentially. So what?!
I don't know :( <br>
Ideally, it shouldn't happen at all or at least in some rare cases, but
when it happens, the server will not be able to catch up with the time.
<br>
Things might be better if we call dWorldStep with the real elapsed time
which will at least prevent accumulation of server delays. (Considering
the current slowness of the server (at least in my system!), this may
change nothing at all, but it might be better when the server is
optimized a bit?!)<br>
<br>
Thanks a lot,<br>
Hedayat<br>
<br>
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  <pre wrap="">.....
Best wishes!

Xu Yuan

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