I'm not sure what you mean by virtual objects. Obj is in the context of 3D
objects is usually the wavefront
<https://en.wikipedia.org/wiki/Wavefront_.obj_file> format.
If you have an object database with *.obj's in it, the probability is very
high, that you don't have pointclouds whatsoever.
You can try this, to confirm my hypothesis:
using GLVisualize, FileIO
obj = load("file.obj")
w,r = glscreen()
view(visualize(obj))
r()
Or just download any obj viewer from the interwebzz and look at that thing.
If you have nice smooth surfaces, you're getting it all wrong with the
pointclouds and ray tracing.
I could give you some hacky way of extracting depth images with
GLVisualize, if that's what you're after.
In that case, just try the example above and if that works, open an issue
at GLVisualize that you want depth images. Then we can take it from there.
If by any chance you DO have pointclouds stored in an obj file, things are
more complicated since you then need to approximate the surface of that
cloud.
Still, raytracing wouldn't be your friend ;) If you have infinitely small
points, there is no magic that lets a ray hit these points any better then
some other visualization algorithm.
Even if it's really dense, you still have infinitely small points. You can
treat the points as particles, to give them some "body" that you can
see, but then it's not really a surface anymore.
Just google for pointcloud surface approximation and see where that gets
you.
I'm guessing here, that you have some sensor that outputs depth images and
you want to recognize objects in these depth images.
To train your depth image classifier, you need depth images from a lot of
perspectives from a lot of random 3D objects, which is why you searched for
a 3D object database, which got you to the obj files of random 3D objects.
It'd have been a lot easier, if you just stated this in your problem
description, probably even with links to the obj database.
Best,
Simon
Am Freitag, 20. November 2015 16:18:46 UTC+1 schrieb kleinsplash:
>
> I was wondering if someone could help me out with a decision/offer an
> opinion:
>
> I need a ray tracer that deals with complex geometry (a fast ray tracer
> that can create 1000's of point clouds in minimal time)
> Python has methods: http://pyopengl.sourceforge.net/ that I could get to
> grips with. But I want to stick with Julia.
>
> I have found these resources:
> https://github.com/JuliaGL/ModernGL.jl - not sure if this has a ray
> tracing option
> http://www.cs.columbia.edu/~keenan/Projects/QuaternionJulia/ - looks
> crazy complicated
>
> https://github.com/JuliaLang/julia/blob/master/test/perf/kernel/raytracer.jl
> - looks like only handles simple geometry
>
> Could someone point me in the right direction?
>
>
>
