Interesting,
Considering that your triangle caching system only works when objects
haven't moved in relationship to the viewport, this benefit would only
be apparent during those situations, right ?
PV3D is currently memory stable, and wouldn't consume more then
needed. The clipping system we have uses triangle caching, and overall
no difference is noticeable, in that case. That is based on my
comparison tests, though, so that might be biased.
This would also explain the speed difference zincuntrin is seeing.
Most likely his view is entirely dynamic, in which case PV3D's
optimizations stand out. Of course, this can change on a per case
basis, since if you would do no specific optimizing per engine,
different features stand out.
Regards,
Ralph.
On Mar 9, 2009, at 7:20 PM, Rob Bateman wrote:
Hey Zincuntrin
here's an inconvenient truths about the flash 10 drawTriangles
method - it is, in almost all use cases, slower than using standard
flash 9 drawing commands. the reason we use them at all is so that
perspective correct textures are possible - which can achieve speed
increases in other ways (such as not having to use the subdividing
algorithm in f9 for perspective correction). But if you do a
straight comparison, you will rarely see any benefit.
The one case where this is not true is when you use indices to draw
your triangles, which reuse vertex coordinates for neighbouring
triangles. But this is not the whole story, because there are a
couple of problems with this approach:
a) not only is the vertex coordinate reused, but the uvt coordinate
is reused as well. It is baffling why this should be the case, as
almost all modeling programs export a format that allows uv
coordinates to be polygon-dependent, and vertex-independant. In draw
triangles it is the other way around - so using indices restricts
your uv mapping to a non-standard form that will break most imported
models.
b) there is a common problem with all new methods in f10 that use a
long string of vectors values, and it is called marshalling.
basically this the name given to the process required to 'marshall'
your values into a single vector for processing in the method. In
tests carried out on the drawtriangles class, the marshalling
process for using drawtriangles with indices neatly removes any
speed benefit that would be gained. In fact, the marshalling process
is still a problem even if you don't use indices, because you have
to concat all your screenvertex values every frame. However, this is
at least a process that can be improved, and will hopefully see some
speed increases as the Flash10 branch matures.
@Ralph - you're absolutely right, the sorting process is no
different in Away3d and PV3D. Although one area where we do differ
quite a lot is in object pooling, which in Away3d is tied into our
triangle caching system. Afaik there is currently no equivalent
system in PV3D, which should mean that Away3d is better performing
when it comes to memory consumption and GC calls over time.
@Zincuntrin - if you compare the f9 version of Away3d with the f9
version of pv3d, there should be less of a difference in speed. I'd
also be interested to see what difference there is between the
Flash10 branch of Away3d and the cs4 branch of pv3d, using the same
drawtriangles methods...
atb
Rob
On Mon, Mar 9, 2009 at 5:33 PM, Ralph Hauwert <[email protected]>
wrote:
Actually, right now Papervision3D and Away3D have exactly the same
sorting options.
As far as I know, by default both PV3D and Away3D exhibit the same
sorting behaviour.
Ralph.
On Mar 9, 2009, at 4:18 PM, Peter Kapelyan wrote:
Can you also try this on your model
mymodel.ownCanvas=true;
I think the reason pv3d is faster is mainly because of it's poor/
simple Z sorting.
If you enable ownCanvas on your model, it should be faster a bit.
Let me know if it is any faster.
Also I hear enhancements to f10 are still underway, but I am sure
Rob can speak more about that.
-Pete
On Mon, Mar 9, 2009 at 8:02 AM, Zincuntrin <[email protected]> wrote:
I have compared Away3D "flash 10" branch with papervision "flash 9"
branch.
Using a model with aprox 2000 tris, I get 40 FPS with Away3D and 60
FPS with papervision.
I have digged into the code and I have seen that you are not using
the
"render batch triangles" feature of flash 10
(graphics.drawTriangles?), but instead, you are still using the
"triangle by triangle" approach, though using the
graphics.drawGraphicsData in flash 10.
Am I correct?
It would be nice, if possible, to know the future plan for flash 10
usage, for example: What are the expected performance gains? When
will
it be ready? etc...
Many many thanks
--
___________________
Actionscript 3.0 Flash 3D Graphics Engine
HTTP://AWAY3D.COM
--
Rob Bateman
Flash Development & Consultancy
[email protected]
www.infiniteturtles.co.uk
www.away3d.com
