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rock
09-13-2003, 06:35 AM
Hi,

New to nurbs, I have tried to do this exercise, but when I render with mental ray under production mode, I don't get the sharp edges as shown in the following attachment.

To create the object, I basically combine 3 ten-segment arc curves and a rectangular curve to form a closed curve. I then duplicate that closed curve and loft them. Then planar trim on both sides. Then render.

I have two questions:

1. Can someone tell me what steps I am missing to get the professional edge when render? Raising Mental Ray Min to 0 and max samples to 2 and checking jitter do not seem to help.

2. Can we get sharp curve edges by using polygons? If so, can you describe the steps to create the object.

Thanks.
Rock

rock
09-13-2003, 09:47 AM
Here's another render - with no settings changed. I think it's just my monitor acting up in the first case above. But I would like to know the answer to the second question: Can the polygon method produce this same object with the same nice sharp curved edges in the arcs? If so, what's the method - boolean? It may be too many tris/quads/subdivs to produce that kind of perfect curve with polygons?

galactor
09-13-2003, 09:52 AM
To increase the smoothing of a Nurbs object, you have to go to the Shape tab in the attrEditor. Go to the tesselation section and increase the UV value. You can even see the result in your viewport by activating the option box in that section.

:: Galactor ::

DeathBrain
09-13-2003, 01:13 PM
Originally posted by rock
Hi,
New to nurbs, I have tried to do this exercise, but when I render with mental ray under production mode, I don't get the sharp edges as shown in the following attachment.

Hi rocks,
Mental Ray production mode has high value of antialiasing (very soft), if you want to get the sharp, try to use standard render with :
Preset : Custom
Edge Anti-aliasing : Medium Quality

http://www.geocities.com/zigaretos/qual.txt

:)

rock
09-13-2003, 07:34 PM
Galactor - Thanks. It was actually fine all along, as in a7.jpg. What I also did was in the NURBS Surface Display section of the planarTrimmedSurfaceShape, I raise the Curve Precision, and CRV Precision Shaded to a maximum value.

DeathBrain - Thanks. The render was fine all along. On another topic, I am waiting for your site to be up. I have been very impressed looking at your "Since 1912" rendition. It's gorgeous. Did you use polygon for the arcs? If so, how would you use polygon to create something like the picture (a7.jpg) that I attached?

DeathBrain
09-13-2003, 07:57 PM
Thank you rock..i really appreciate it :)
Most of all was done by polygon, except pipes, wires, or other smooth things, on "since 1912" scene, only the clock was done by nurbs), ohh man...of course i am not going to use nurbs with 2900 objects :surprised

Btw my intents is to the lightings, texturing & global depth env setup, not to the model them self, as you know...all of my stuff was done by with simple poly models, cylinder, boxes, torus, bevel stuff, etc.
But its really hard to setup the lightings, texture, soft fogs, depth view & environment :blush:

Btw, I'll send you a Message when my site is finished & uploaded :beer:

DeathBrain
09-13-2003, 09:50 PM
Btw here's my stupid pilar on "since 1912" scene (all was done with poly)..poly..poly and poly..:blush:

http://www.geocities.com/zigaretos/pilare.txt

DeathBrain
09-14-2003, 12:30 AM
Originally posted by rock
If so, how would you use polygon to create something like the picture (a7.jpg) that I attached?
I created an arc based-spline with coreldraw, import to Maya, then bevelplus with extrude distance 5 and outerstylecurve convace-in :)

Btw check your PM Please :)

rock
09-14-2003, 12:44 AM
DeathBrain,

Thank you. Bevelplus works beautifully. It's exactly what I wanted. I am still learning. I left that "Since 1912" you did on my desktop for 2 straight days now, getting renewed energy by just looking at the picture when I get stuck.

DeathBrain
09-14-2003, 12:59 AM
Yea.. Bevel Plus is really cool stuff :)
After beveling, don't forget to adujst/increase the poly level sampling

http://www.geocities.com/zigaretos/bevel.txt

So the poly will looks zzzmootth...:cool:

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