KeyShot Forum

Technical discussions => Textures => Topic started by: fario on August 29, 2017, 08:03:19 AM

Title: continuous reflections
Post by: fario on August 29, 2017, 08:03:19 AM
Hello,

How to obtain continuous reflections on a smooth surface without textures?

Thank you for your reply  :)

plz, look my demo:

https://www.screencast.com/t/a3mQjLKE

https://www.screencast.com/t/GoTsWCSS

Antoine
Title: Re: continuous reflections
Post by: DriesV on August 29, 2017, 08:17:58 AM
Hi Antoine,

You will want to have curvature continuity, often denoted as "G2" in (surface) modeling software.
Here (https://docs.mcneel.com/rhino/5/help/en-us/popup_moreinformation/continuity_descriptions.htm) is some useful info from Rhino on this topic.

If the radius of curvature is the same where the two surfaces meet, then the transition is curvature continuous. This will get you smoothly flowing reflections/refractions in KeyShot.

I hope that helps.
How do you build your surfaces?

Dries
Title: Re: continuous reflections
Post by: fario on August 29, 2017, 08:36:37 AM
Thanks Dries  ;)

But i am surprised...

This would mean that Keyshot can not reproduce reality (reflection) on most industrial objects, without having to retouch the fillets  before export ..?

Do not see any critics in my post, but I now only understand the limitations for working with simple reflections on shiny surfaces.

Is this impossible in future developments?
Title: Re: continuous reflections
Post by: INNEO_MWo on August 29, 2017, 09:17:11 AM
I created G2 Radii with creo parametric and imported the geometry to KeyShot - working fine!
Title: Re: continuous reflections
Post by: DriesV on August 29, 2017, 09:38:04 AM
Quote from: fario on August 29, 2017, 08:36:37 AM
... This would mean that Keyshot can not reproduce reality (reflection) on most industrial objects, without having to retouch the fillets  before export ..?

Well, in reality most manufactured and machined products will have "curvature continuity" due to the manufacturing processes involved.
So even when a blend would be defined with tangent continuity (G1) in CAD, it could end up being G2 in the finished product, because of e.g. sanding and polishing.
One area where it can be important to model with curvature continuity is A-sides (outside surfaces) of injection molded consumer goods. If you model with G1 blends, then you risk getting sharp transitions in the mold and thus noncontinuous reflections in the final molded part.

You have to realize that CAD is not reality. It is an approximation and idealization of reality. :)

Also, the blends on the Apple "trash can" are probably quite complex on the original CAD model. I imagine it is much more involved than a simple blend.

Dries