#Hidden Line rendering
13 messages in this thread
Is it possible to do a hidden line rendering in 3DS? I always assumed that
this was a simple thing to do, but I never actually needed to do it. Now, I've
set out to try it and can't figure out a way. Wireframe doesn't cut it,
because objects are transparent and even with 2-sided Off, you see the fronts
of objects that are behind the frontmost object, which is wrong. Also, I only
want to render edges that are visible in the editor, so using a face map
material with just an outline won't cut it (although I'm quite proud of myself
for thinking of this solution <g>). Any ideas?
Aaron
The closest you can get to hidden line in 3DS is by using an outlined face map,
Aaron.
– G
> The closest you can get to hidden line in 3DS is by using an outlined > face
map, Aaron.
I was afraid that was the case. Now let me ask this question: How does the
renderer determine which faces to apply the map to? Eg., If you have a map
that is simply a square border, and you face map it on a cube, each side of the
cube will be a square. So far, so good. However, if you hide some of the
edges of the cube, it will now render ALL the lines of those faces with hidden
edges. My question: Why didn't it render the hidden diagonal line across the
square cube faces the first time?
Aaron
Aaron
What gets mapped is determined by edge visibility only, as you noticed. If you
want the diagonal to split the face of the cube, just do a Modify/Edge/Visible
and rerender. Don't forget the AutoEdge feature for
complex objects.
TedB
!^NavFont01F0007MGHHGC76088
> What gets mapped is determined by edge visibility only, as you noticed. > If
you want the diagonal to split the face of the cube, just do a >
Modify/Edge/Visible and rerender. Don't forget the AutoEdge feature for >
complex objects.
That's what I would have expected, although it does not work exactly like that.
True, if I have a cube with the diagonal hidden, that edge won't be rendered.
But this seems to only work on flat square faces, or other coplanar sets of
faces. Try this: Create an L-Sphere, not too complicated. Face Map it with a
white frame image as I described in my last message, then render. This looks
like it does in the editor, a bunch of squares. Now, do Modify/Edge/Invisible
on a group of the front edges that you'd be looking at in the render (turn
backface on to make it easier to know which ones to click on) and render it.
According to what you said, There should be a blank spot where the edges were
hidden, but there isn't. Instead, it decides to render all the lines,
including diagonals. Why?
Aaron
Aaron
Hmmm, I'll try to experiment with that this afternoon and get back to you. I
use a white frame now and then but mostly on architectural (i,e, flat) objects
and it works as expected.
TedB
!^NavFont01F0007MGHHG9ED9CF
Ted,
I've experimented with it and it looks like it only works on quadrilateral
polygons with exactly one shared edge. It doesn't matter if the faces are
coplanar or not. Just to quickly see, though, make a hemisphere, face map it,
and look at the bottom (flat) part. There are a bunch of triangles, even when
those edges are hidden in the editor.
Aaron
Geez, Aaron, haven't gotten around to looking at it yet! I'll try to try this
afternoon.<g> Thanks for the experimentation, though.
Later
TedB
!^NavFont01F0007MGHHG7945DB
Ted hit it on the nose.
– G
Aaron;
Another trick that works to render a Hidden line it create a copy of your
objects in the scene which are scale down and away from you camera maybe .1% or
so. Then define the new objects as MATT objects under Modify Objects
Attributes. Once these new objects are in place you then define your original
objects to use wireframe materials. Now all objects behind foreground objects
will not render.
Hope that does the trick.
Zac (AZ-TECH)
Berkeley
Zac,
Your solution sounds like it might work. However, it would be seriously
impractical to have to create copies of every object in my scene, and then
scale them down. The scaling would have to be done locally for each object,
which would be incredibly time consuming. I suppose a PXP or a TSE script
could be written for such a thing, though.
Aaron
Aaron;
>>Your solution sounds like it might work<<
I have used this technique many times for architectural studies, and it _does_
work quite well. Time consuming yes, but the results are just what you are
looking for so it all depends on how desperately you need the effect.
Zac (AZ-TECH)
Berkeley
Aaron:
I just went through a similar series of experiments and trials to get
hidden lines renderred on 3DS. After trying most of what has been
discussed in this thread, I found the FASTEST way to do it is to just
take the model into AutoCAD and use the hide command. Not very elegant,
but it got the job done ! (with excellant line detail)
Good wish-list item.
John