New Build (291)

[Roy Hirshkowitz]

This one introduces two new engines.  Both of these are very experimental at the moment. I may not retain either of them if they don't prove useful.  Although they appear very stable, there may be some hidden bugs.  Be careful using these for production until we have some confidence in their stability and characteristics.  The engines are only accessible via the nXtEngine AutoLisp command use (nXtEngine 2) -OR- (nXtEngine 3).

Both engines include more light pathways than the current product does and can therefore potentially provide more accurate solutions.  Two "tricks" which are used in the first two engines, transparent shadow rays and daylight portals, are not used in these new engines.  This gets rid of two big sources of inaccuracy.  Caustics pathways are automatically included.

Engine 2 can be much less noisy than the Path Tracer for most interiors.  It's convergence, on the other hand,  is not as graceful and will include some discrete artifacts.  It's usually a lot faster than the Path Tracer for interiors.

Engine 3 is a little more accurate than Engine 2, particularly when window coverings are involved.  It converges more gracefully, but slower for some interiors.  It is considerably faster on some exteriors.

Some things to keep in mind with these engines:

• Light leaks in the corners are possible when doing interiors.  Make sure walls, floors and ceilings are modeled as slabs with thickness.
• Both engines start slowly and accelerate.  Pixels/sec should increase as they proceed.
• Using accurate IORs is very important.  IORs of 1.00 should not be used for glass.
• Designating glass as Thick/Thin is more important with these engines.
• Translucency is not implemented.  Allow Surface Roughness is.
• These engines use more memory than the previous two.  64 bit is recommended.  Start your testing and low resolutions.

Let me know what you think-- I'm looking for feedback here.

[Jorge Javier Lara Domínguez]

Use el motor nxtengine 2. En  cuanto al tiempo no note gran diferencia, sin embargo el contraste qeu se genera los rebotes y la definicion de losmapas parecen mejores qeu las versiones anteriores. Para que esenas es recomendable? interiores? Que sucede con los HDRi?. Aun  no realizo ninguna prueba con el nxtengine 3. Espero poder realizarla en estos dias y compartir expeiencias. Saludos

[Roy Hirshkowitz]

All of these tests are valid-- I'm certainly curious how well it performs for various scenes.  The difference between your two images is likely due to a subtle change I made to the tone operator (which I may implement for all engines.)  

You'll probably notice more qualitative difference on interiors, but it's hard to say.  I'm actually liking engine 2 better than 3 at the moment.

[George Ioannidis]

@ Jorge's example of the entrances: The second image (I suppose the new engine) has by far more vivid colours and more "real" contrast (such as we can see in real external space photos)

[Jorge Javier Lara Domínguez]

Aqui tenemos una imagen realizada con ntxengine 3. El mismo tiempo de proceso (165 minutos), misma configuracion de iluminacion, tuvimos 155 pases.

[Marc Chaumier]

Here are 3 pictures, with Engine 1, 2 & 3, 30mn render in 3000x2000.

[Marc Chaumier]

For those who want to try with my dwg, here is the file

[Miguel Tano Adanes]

Hi all. I'm still doing some experiments, but this is what I get till now.

This is e2, 1000 passes, 2:20 hrs.

This is e3, 1000 passes, 1:26 hrs.

I personally prefer e2, even though I don't like too much the dark shadow on the floor close to the piano on the left. But maybe with more passes it gets smoother.

[Roy Hirshkowitz]

e2 is generally looking like a valid approach-- thinking about dropping e3.  The light at the skylight is being severely underestimated in the e2 case-- not sure why.  I don't actually have this full model-- any chance you could upload it again?  When you have time, of course.

[Alejandro Testa]

Here is what I get.  220 passes  E2.

[Roy Hirshkowitz]

How do you think it compares to e1 (path tracer)?  I may not be able to get rid of the junk that's in the foreground.

[Miguel Tano Adanes]

Files uploaded!

[Miguel Tano Adanes]

I have to say that I prefer the luminosity of e3. Even if in this case it should be more balanced. I haven't retouched the nxtimages files. This is just as it is! Model files uploade, Roy.