Re: [Visualpython-users] VPuDig, V 42, Is 5, Tim Smith and *speed*

[John B. <jb...@te...>]

In general, I seem to have passed through this same points/speed bottleneck 
and am now trying to get my points-packing program C++ version to use OpenGL 
rendering.  If there's any applicability to Tim Smith's problem, there are 
VPython and C++ versions of this (source is obvious in the Python/VPython; 
source for the C++ is included) program (not yet the C++ OpenGL, which I'm 
still fighting) here :

http://tetrahedraverse.com

The C++ program with source (and other stuff, including Martin Kraus' 
live.jar and a pointfield-viewer called Graph3D by a man named Hart) package 
is behind the wee tiny line of text ("NEW! Windows..."etc.) just under the 
"Tetrahedraverse" label,
and the VPython original program that does all those points (any number, 
user-entered) and renders them is at :

http://208.131.134.190/tverse/engine/engindex.htm

(Which is behind "tetrahedraverse" :: "ball packing" :: "my own packing 
program" )

If you're going to pack (use; render; calculate about; do-something-with) a 
million or more points, you're going to need something faster than either 
VPython *or* Python.  Speed was one of the two main reasons I had to learn 
enough C++ to port my Python program into that language (I was *not* about 
to try to port it to Assembly, the only thing faster than C).
The other reason was public acessibility: I wanted to allow at least Windows 
users to download the (Windows, console) program and be able to run it right 
away, with no installation of anything otherwise necessary.  (To run a 
VPython program, the potential user has to have a Python/VPython 
installation locally on his computer.)

If anything in either of my point-packing programs is useful to you, Tim, 
you're welcome to them and their source.  I, too, have to deal in many 
thousands of points.
(The VPython original displays the point field moving/packing-itself in 
'crosseyed' stereo 3D....)

John Brawley


----- Original Message ----- 
> Message: 2  (And others in this thread...................)
> Date: Tue, 17 Nov 2009 11:20:42 +0800
> From: "Tim Smith (25121)" <tk...@mi...>
> Subject: [Visualpython-users] speed
> To: <vis...@li...>
> Message-ID:
> <277...@mu...>
> Content-Type: text/plain; charset="us-ascii"
>
> Something I've noticed with vpython is speed doesn't seem to scale up.
> In my model I found 1000 points has a render time of 17, 10,000 points
> has a render time of 170, and 50,000 point has a render time of 445.
> Once I go over the 10,000 point mark performance starts to go down
> exponentially.
> What I'm wondering, is I'll potentially have to render 1,000,000 points
> for one of my projects, is vpython unsuitable for my task and is there a
> faster python 3d library out there? I've been really impressed with how
> fast vpython has enabled me to produce from very detailed models, how
> ever working with such slow objects is going to drive me a little batty
> eventually.