Re: [Visualpython-users] vpython as a visualization window

[Bruce S. <Bru...@nc...>]

Don't count on transparent faces very soon. There are serious issues 
with transparency in general. The current implementation of transparent 
object works well enough for some purposes, but it is easy to construct 
examples where the rendering is incorrect. The problems are exacerbated 
with objects that aren't convex, and an object built using the faces 
object is likely not to be convex.

It is conceivable that a different scheme for handling transparency 
might be implemented in such a way that transparency for faces would 
come along as a welcome side effect.

I should say that the highest priorities for those of us currently 
working on Visual is to create a production-quality Visual 4, and to 
create a native-mode version for the Mac that is easy to install, uses 
native-mode graphics instead of X11, and does not require installing 
fink. Improving or extending transparency has lower priority.

Bruce Sherwood

Grześ Furga wrote:
> Hi,
>
>
> I'm writing an experimental brain atlasing tool and I'm looking for
> visualization options. As I need to (or rather: want to) process my
> geometry at a triangle level by hand, VTK seems to complicated.
> I'm fairly proficient with opengl programming, so I feel comfortable
> with pygtk / pygtkglext / and a custom widget handling simple mouse
> interaction.
> It's all pretty straight forward and seems the easiest way to
> implement custom camera interactions or whatever fancy interface i can
> imagine.
>
> Of course using "raw" pyopengl has serious performance issues, and I
> might be forced to code variable level of detail schemes for data
> sizes I could otherwise throw at a c implementation without
> hesitation.
>
> So I'm basically looking at options to separate opengl drawing calls
> and mouse interaction to a c implementation, while still being able to
> modify my data from python, visual python looks really promising to
> me, but I think I would only use the frame and faces primitives.
> What I really need though is transparency options.
>
> I know that the beta version doesn't support transparency for the faces shape.
> I'm very curious what is the estimated time for this feature to
> arrive? Are there any problems with adding transparency handling to
> the faces renderer, compared with the other primitives?
>
> I would also like to hear from anyone using visual python as a simple
> polygon pusher / viewer. Maybe You can suggest something simpler?
>
>