#Bump edge question
18 messages in this thread
Hi again fellow "sit-in-the-dark-and-make-nice-pictures" dudes.
Does anyone know what the technical term is for rendering an object with it's
EDGES disturbed by the bumpmap?
I have a model making friend who always gives me grief about bump-mapped
surfaces that have utterly smooth contours! Don't you just hate those
traditionalists! Building things by hand.. BAH! (g).
And …. er …. Is it possible/hard etc to write an IPAS that would do this or
would that be something which would have to be implimented in the code of the
3DS.exe?
Thanks in advance…
Glenn Zephyr.
It's called displacement mapping, and you can get exactly the same effect with
displacement modeling, using Displace.pxp.
– G
Hi Glenn,
Curiously enough, at least with Digital Arts we called it a "displacement map",
which (get this) "perturbed the surface normals".
As your aware the Yost has Displace and it seems that it would not be that
difficult to reproduce with the same code. It would act like an AXP based on
the contrast of the map, but the developer would need some kind of "materials"
interface so that you could assign the material and give it "surface normal
peturbation" values. Try saying that real fast 3 times. <g>
John
>>technical term is for rendering an object with it's EDGES disturbed by the
bumpmap<<
displacement mapping. There is also something called hypertextures that I
believe adjusts the geometry also but I don't know much about these.
>>And …. er …. Is it possible/hard etc to write an IPAS that would do this
or would that be something which would have to be implimented in the code of
the 3DS.exe<<
Hmmm, I don't know what info is available to an IPAS but it might be possible.
Very impracticle though, it would be much more efficient built into the
renderer. I don't know if any PC programs have displacement mapping. To do it,
it actually modifies your geometry and will make it really complex by having it
model all the bumps of the map. When I had the opportunity to work on Alias I
was told about this kind of mapping, but the person showing me about it said
that it takes a lot longer to do then simple bump mapping; and this is on a
silicon graphics machine!
It would be nice too have this but as far as I know it is too much for
a PC. Maybe some IPAS writer is working on this, I would hate to see how
complex objects got though. Maybe if it only modified the edges and where
objects intersect you could get the effect and save alot of geometry. I dabble
in 3D crap and have an idea how to produce displacement mapping without
modifying geometry but it's all theoretical.
Hopefully Yost Group will find a way to implement this, I think they
easily could.
———–Will
Glenn:
>> Does anyone know what the technical term is for rendering an object with
>> it's EDGES disturbed by the bumpmap?
I think it's technically called "rendering an object with it's EDGES disturbed
by the bumpmap". <bg>
Seriously, I'd just use DISPLACE to quickly bump out the object, right to and
including the edges.
Greg Pyros
Thanks Greg (and all others who responded!),
I am aware of the very powerful dispalce.ipas by Gary's buddies and it's a
powerful app. but I was wondering if it was possible to affect only the edge at
render time without jacking up the complexity of the mesh (the same way a bump
map does).
BTW Greg.. Long time no type! How's things? Busy?
Glenn Zephyr.
Hi Glenn,
<< but I was wondering if it was possible to affect only the edge at render
time without jacking up the complexity of the mesh >>
a silhouette data structure of faces on this edge as seen by the camera..wish..
got it. wish I had it.
jonas[adesk]
>>a silhouette data structure of faces on this edge as seen >>by the
camera..wish..
Jonas you really know how to distill a concept! What a wordsmith! <G>
Glenn Zephyr.
Glenn:
>> BTW Greg.. Long time no type! How's things? Busy?
Yes, very. Unfortunately, my wife's father died right after the New Year, and
we traveled back for the funeral in Pennsylvania.
But we are back into it now, working on a TV show, a CD-ROM game, two
architectural animations, an accident reconstruction, and the graphics which
will be displayed on TVs and computer monitors during a feature film. Whew,
I'm getting tired just looking at our production schedule for the next few
months!
How's things down under?
Greg Pyros
<<my wife's father died right after the New Year Sorry to hear. That's always
tough stuff to get through.
<<How's things down under? Well… Holly wood it 'aint. It's not hard to be a
big fish in such a small pool!(G) As we have our summer break and Christmas
simultaneously, everyone's just getting back into things so I'm quoting but not
really hard at anything in particular. Your schedule sounds like big fun!
Glenn Zephyr.
Glenn:
>> Your schedule sounds like big fun!
You are invited to come on over whenever you want to play!
Greg Pyros
>> affect only the edge <<
Take your map and black out all but 4 vertical, evenly spaced sections.
Cylindrically map w/ Displace.
>> without jacking up the complexity of the mesh <<
Yea well… better than nothing.<g>
Interesting tip Wade… I'll have a play with that!
Glenn Zephyr.
>> Seriously, I'd just use DISPLACE to quickly bump out the object… <<
Yeah, I agree Greg, but what do you do when you want to put a bumpy surface on
a SKINNED model? <g>
John
JE:
>> Yeah, I agree Greg, but what do you do when you want to put a bumpy
>> surface on a SKINNED model?
Good question! Are there any other good questions out there? :^)
Greg Pyros
Good question! Are there any other good questions out there? :^)
Everyboby's a comedian. <g> The answer is a Displacement Mapping AXP. 🙂
John
<<The answer is a Displacement Mapping AXP. :-)>>
I'll second that wish! I can just imagine the possibilities of morphing
between 2 Displacement Maps.
>>morphing between 2 Displacement Maps
Or using a flic as a source, or doing it as Lightwave does, by moving a picture
across. Either would make me happy.
John Stetzer
JWS