[Python-Dev] [Visualpython-users] How VPython 6 differs from VPython 5

[Mark Janssen]

On Sun, Jan 13, 2013 at 12:14 PM, Bruce Sherwood
<Bruce_Sherwood at ncsu.edu> wrote:
> For the record, I do not know of any evidence whatsoever for a supposed
> "split" between the tiny VPython community and the huge Python community
> concerning floating point variables. Nor do I see anything in Python that
> needs to be "fixed".

Well it was bit enough that the python community created a brand-new
language construct called import __future__ -- something never
considered before then and which actually changes the behavior of
python unlike any other module.  And perhaps I've just felt it more
because I was a big proponent of both 3-d graphics as a way to keep
python a draw for beginning programmers and also a big fan of
scientific simulation.  No one had anything near vpython back then.
(But ultimately I need to stop mentioning this issue to this vpython
list because it's really the Python group which need to get back in
sync.)

> The new (currently experimental) version of VPython based on wxPython must,
> in order to run in a Cocoa environment on the Mac, make the interact loop be
> the primary thread, with the user's Python calculations at worst a secondary
> thread, which is the opposite of the older VPython, where the
> interval-driven rendering thread was secondary to the user's calculations.
> By the unusual stratagem of having VPython import the user's program it has
> been possible to make this work, and at the same time greatly simplify the
> C++ component of VPython by eliminating threading, with additional important
> simplification from eliminating essentially all platform-dependent code
> thanks to the multiplatform character of wxPython. The result is that nearly
> all existing VPython programs will work without change, at the very small
> cost of a few marginal cases requiring minor tweaking. I should alter the
> documentation to make this important property of the new version more
> salient.

I need to analyze this more carefully before commenting further....

mark