Object tesselation...

[ErikE]

Hi everyone!!

Im an architect using AutoCad2002 for modeling in my work. I using extruded polylines and circles(for colums)in most cases.
I use 3D Studio Max for rendering and heres where my problems starts. I cant find any options in AutoCad where I can adjust the tesselation of an object. Especialy when Im exporting extruded circles.
Is there a command in AutoCad where I can set the tesselation before Im extruding...

Any hint would be appriciated!!!


Erik

 

[CADaver]

Clarify what you mean by "tesselation". In ACAD it refers to how the solids are viewed (not built).

 

[borgunit]

Try the SURFTAB1 variable.

"Whether you think that you can, or that you can't, you are usually right "
.. Henry Ford

 

[borgunit]

I think this can help. It has a little description of the controlling variables on page 4 ...

http://www.accustudio.com/forum/tutorials/course-2.pdf

"Whether you think that you can, or that you can't, you are usually right "
.. Henry Ford

 

[ErikE]

Hello again....And thank you for your response!!

I better clarify what I mean about tesselation. I know that tesselation refers to how an object is wieved in Acad, but I mean how a solid is buildt, and how many polygons it consist of - (Im sorry for the confusion)...Its a matter of how smooth a round shape is when its exported to Max, etc..

to Borgunit:

Thanks for the vey fine tutorial - it cleared up a few things for me. But the SURFTAB variable is for surfaces not solids...I could not find any variables related to this function...
In my work I use the boolean commands(union,subtract, etc.) to cut out holes and other things..

So I hope you can give a little more help on this one...

And thanks again



Erik

 

[ErikE]

Ok...Folks..

I found out how it works!!!! just 1 min after I placed this reply - how typical!!!!

It the FACETRES command you have to use!!!

What a learnfull day..


Erik

 

[CADaver]

Commands that effect display: FACETRES, VIEWRES, ISOLINES, DISPSILH, and FACETRATIO

However, even FACETRES only controls the "display" of a curved SOLID, and can be changed after the solid is constructed.

From AutoCAD's Help for FACETRES:
You can control the display accuracy of curved objects by using theVIEWRES command and the FACETRES system variable.

Control Display of Circles, Arcs, and Ellipses
The value you set with VIEWRES controls the display accuracy of circles, arcs, and ellipses. AutoCAD draws these objects on the screen using many short straight line segments. The higher the value set in VIEWRES, the smoother the arc or circle looks but the longer it takes to regenerate. If the circles look like polygons in the drawing, they'll look like polygons when rendered. To increase performance while you're drawing, set a low value with VIEWRES. However, to make sure you get a good-quality rendering, raise the value before rendering drawings containing arcs or circles.

Control Display of Curved Solids
FACETRES controls the smoothness of shaded and rendered curved solids. It is linked to the value set by VIEWRES: when FACETRES is set to 1, there is a one-to-one correspondence between the viewing resolution of circles, arcs, and ellipses and the tessellation of solid objects. For example, when FACETRES is set to 2, the tessellation will be twice the tessellation set by VIEWRES. The default value of FACETRES is 0.5. The range of possible values is 0.01 to 10.

When you raise and lower the value of VIEWRES, objects controlled by both VIEWRES and FACETRES are affected. When you raise and lower the value of FACETRES, only solid objects are affected.

Note: VIEWRES only controls display smoothness in the drawing window. Hidden and rendered views are controlled by the system variables, FACETRES and FACETRATIO, both of which can also be controlled or adjusted by VIEWRES.

You may also wish to look at ISOLINES and DISPSILH for other display controls

 

[ErikE]

Thank you both!!

You been very helpfull...


Erik