PDA

View Full Version : Shade Lines


Igors
07-11-2006, 09:48 PM
Hello, gentlemen

We are investigating "Shade Lines", and, be honest, we don't understand how it works. In any case we can't achieve what we need/want: shade them as thin accurate cylinders. What is your experience here ?

Jens C. Möller
07-12-2006, 07:56 AM
Hello Igors,

I guess that "shade lines" uses some hybrid technique of shading a solid object an masks it with the line renders. Lines however have no thickness, so you need to define a size in pixels rathrer than world units. Close lines have the same thickness as far away lines. It would be desirable to shade them like cylinders though...

Jens

NorthernLights
07-12-2006, 02:06 PM
What Jens said.

Could be tricky with ray-tracing math though. This is why Joe Alter uses Volumetric Rendering to do hair besides the fact that storing the data for millions of hairs isn't practical.

Igors
07-12-2006, 03:55 PM
Could be tricky with ray-tracing math though. This is why Joe Alter uses Volumetric Rendering to do hair besides the fact that storing the data for millions of hairs isn't practical.We don't relate this with hairs (yet). But just interested in good lines.

- "Shade Lines" has no effect if lines has no vertices normals (as, BTW, Ubershape creates);

- if normals are here, "Shade Lines" uses them same as for normal geometry. So, wireframe = thin flat ribbons sticked to original surface

Hmmm... we don't like that. Thinking...

NorthernLights
07-12-2006, 10:58 PM
Ah, but which way do you point the normal?
(And what is the sound of one hand clapping?)

If they are to be treated like cylinders then they have an infinite number of normals. You couldn't simply aim the normal at the camera because they'd never have any fall off.

But I'm much more concerned with memory consumption. One line consumes a minimum of 56 bytes (24 doubles and 2 longs). 1 Meg is about 17k lines roughly.

Igors
07-13-2006, 08:59 AM
Ah, but which way do you point the normal?
(And what is the sound of one hand clapping?)

If they are to be treated like cylinders then they have an infinite number of normals. You couldn't simply aim the normal at the camera because they'd never have any fall off.Theoretically lines' normals should be inherited from surface (as wireframe does). But it's just "better than nothing"

But I'm much more concerned with memory consumption. One line consumes a minimum of 56 bytes (24 doubles and 2 longs). 1 Meg is about 17k lines roughly.Alas, practically it takes in 2-3 times more bytes. But in any case hairs render is not for standard phong.

Igors
07-13-2006, 06:16 PM
Aha, clear now (2 wireframe baskets are attached :) )

Jens C. Möller
07-14-2006, 08:10 AM
Wow. Now THAT is cool! How did you do this?

Jens

Igors
07-14-2006, 12:12 PM
new shader (freebie :sad: )

halfworld
07-14-2006, 12:40 PM
new shader (freebe :D )


;)

Vizfizz
07-14-2006, 03:26 PM
Superlines will be posted on Paralumino's website soon. Keep checking in.

Hiddenman.fr
07-15-2006, 07:06 AM
Hey Igors as you seem to investigate EIAS world go to that link:
http://graphics.pixar.com/index.html

I'm sure you will find interesting informations to develop new tools for EIAS.

Glad to see you work hard for us.

Igors
07-15-2006, 10:02 AM
Hi, StephaneHey Igors as you seem to investigate EIAS world go to that link:
http://graphics.pixar.com/index.html

I'm sure you will find interesting informations to develop new tools for EIAS.Thx, but for us a good idea never comes from "a cool link", but from real practice and from relations with people. Well, same SuperLines for example. During writing a new tool (based on ideas of heretic Uwe) we've noticed that output shading is very poor. We tried to learn, investiagate etc.

So, instead of referring to pixar, tell us your understanding/viewing of things/problems, and, maybe, something interested and usable can be implemented (chances are not very high though :) )

bronco
07-15-2006, 10:36 AM
so, igors, do you care to tell us which of my heretic ideas catched your interest? :)
(i just hope the inquisition will never knock on my door)

btw, superlines looks really nice and cool. nice addition to trestle.

Igors
07-15-2006, 11:53 AM
Hi, Uwe..which of my heretic ideas catched your interest? :)You'll see yourself (we plan to send you beta next week)

Vizfizz
07-16-2006, 12:27 AM
Come one come all... Parlumino's Superlines shader has posted. Let us know what you think.

http://www.paralumino.com

richardjoly
07-16-2006, 04:36 AM
Must be a very thin line... Can't find it.
I believe waiting til tomorrow will do the trick.

Vizfizz
07-16-2006, 04:58 AM
Its on the site Richard.. check the left hand side bar.. click on Superlines.

richardjoly
07-17-2006, 12:13 AM
Got it! Guess I was too eager and tryed to get it before the site was updated.
By the way, congratulation to Eric for the new site design. I really dig it!
...I even play with that swoosh logo just to ear the wive say "what was that?"

CGTalk Moderation
07-17-2006, 12:13 AM
This thread has been automatically closed as it remained inactive for 12 months. If you wish to continue the discussion, please create a new thread in the appropriate forum.