NURBS surfaces should be called NURBS membranes


That was very pleasant. Thank you.




In every rumor there is a little bit of truth :wink:


Don’t quote me for these translations. I was just trying to find other words for what I’ve studied 40 years ago:


Hi @Jess,

I couldn’t resist. Here a 3D view from the olympic park of my hometown Munich:




Yeah, works great with your Rhino glasses! :slight_smile:


This topic has been raped and mutilated.:sob::face_vomiting::policeman:


You should never leave your kids alone. I’ve tried to follow your thoughts and explained why I think “membrane” is confusing. I’m still waiting for your reply but if you are not interested in a serious discourse then we cannot help. Of course you’ll need a thick skin when trying to break very old habits…


Well, cause it is still weekend: This problem is also known as the candlewick’s event horizon… :wink:

(David Rutten) #58

A flame is a volumetric entity, not a surface type shape. In the sense that you can imagine a surface there it is defined as connecting points of the volume with a specific shared property (emitted wavelength most likely). It is therefore either an iso-surface, or maybe even an interface if you can describe the surface as the boundary between two dynamic fluids.

The dusk of the term NURBS "surfaces"!?
(David Rutten) #60

What we have a volume which contains varying temperature from place to place. Air with a specific temperate emits light of a specific wave-length-distribution. Some of these look white to us, some orange, some blue, some we can’t see at all because all the wavelengths are in the infra-red. However to pick this transition from visible-to-invisible as the shape of the flame would be anthropocentric in the extreme. Vipers and insects would disagree with us as to exactly which iso-surface represents the boundary between visible and invisible, as would almost any mechanical camera.

Although it is possible under very specific conditions for different photons to interfere, when talking about interference in the messy real world it almost always relates to the wave-equation of a single photon interfering with itself.

Photons are indeed bend by the curvature of space-time (both according to Newtonian and relativistic theories, Einstein merely thought they would bend more and was proven right) but the amount in which photons attract each other is so ludicrously small that it might as well not be the case. Note that both photons and gravity waves travel at the speed of light and therefore experience total length-contraction and time-dilation. Photons travelling side-by-side don’t have time to feel the effects of their neighbour and as such do not affect each other. Photons travelling in opposite directions will be slightly deflected by the space-time-wake of the other one.

Photons are not matter. They have no rest-mass.

(Wim Dekeyser) #62

Oh, the irony - Rhino disagrees as well…

(David Rutten) #63

I didn’t realise you were using ‘interference’ in the colloquial sense, what with all this talk of photons and matter and mass. My comments were strictly about quantum-waves.

Before I get drawn into that discussion though, we first have to agree on the meaning of “is”.

I think that ship has come, gone and sunk to the bottom with the loss of all hands.


redefining the question of being for which we sincerely have not the depth for (referring to the endless boundary) will probably not help finding anything fulfilling in the context of this discussion.

i think it has not even arrived and must´ve sunken long before.


Insane in the membrane… Cypress Hill.

Scrolling down this long and ever thinning thread can seriously damage your mouse wheel finger’s tendons!


You can use Monolith for that ( or any other voxel based modeller for that…“surfacic” or solid modellers are not good at all defining the change of properties inside volumes.

BTW, wtf is this post??? :smile: