Posted by David A. Smith-3 on Nov 17, 2006; 3:39pm
URL: https://forum.world.st/Hedgehog-rendering-tp129460p129461.html

David Faught wrote:
> Here is yet another naive question (or three) from my vast arsenal.
> Does rendering code run within the island?  Maybe on behalf of each
> avatar replica?  Even though it will never actually be viewed
> directly?
Rendering actually runs outside of an Island. It is not a replicated
process, hence you only render what shows up on the screen - basically
as little as possible.
>
> So that if I am running an island, router, and harness/avatar camera
> all on one PC that rendering code has to run twice, once for the
> island and once for the avatar?  And if someone else joins my island
> then twice for the island and once for my avatar for a total of three
> times on my PC?
No. Only one rendered view. There is some code in there that renders the
scene for each avatar once a second or so, but this has very little
overhead and will be going away soon. It will be replaced by a more
general mechanism.
> The real problem that I am trying to get at with these questions may
> not be related at all.  I have noticed that scenes with many rendered
> objects are dramatically slower in Hedgehog than in Jasmine.  While
> trying to update my DualMaze project, I noticed that it was very slow,
> so I reduced the number of rendered surfaces by a factor of 3 by
> changing the maze walls from TCubes to a dual-faced TRectangle
> subclass.  This gave adequate performance, but still a bit slower than
> Jasmine was with the TCubes.  I have also noticed that the fps of more
> complex figures done with MockTurtle goes down dramatically.
The rendering speed should be about the same, if not a bit faster in
Hedgehog. There is a lot more going on in Hedgehog now, though. There is
additional overhead in the replication. Also Jasmine would update
certain things like particle systems at render time, - hence you would
only compute updates to an object when it was visible. With Hedgehog,
you can't do this anymore, so particle systems are always computing -
not rendering, though computation is not free. We have worked out a
number of patterns for managing this kind of situation, and it should
show up in a later release.
>
> Any idea what is really going on here?
>
>
>