TheSwamp
CAD Forums => Vertically Challenged => Topic started by: nobody on July 31, 2015, 04:36:27 AM
-
To my hearts discontent, I am unable to resurrect nostalgia, and build that loop-d-loop I dreamed so much about. I pontificate, is Civil 3d really 3d, or just an illusion of 3d. Should we have all taken the other pill?
-
Civil 3D is often not even Civil, much less true 3D
-
it appears possible -tedious to setup - but likely possible to trick C3D into it
-
Civil 3D is often not even Civil, much less true 3D
This.
-
but.... Dirt 2.25D just didn't have the marketing cachet to be a product name :whistling:
-
Haha
The concept of having a 2D Alignment and 2D Profile designed within the confines of a 2D Profile View, which combined, represent a 3D Vertical Alignment, leaves a lot to be desired.
Especially, as compared to that of a single 3D entity (NURBS? I 'spose Feature Line will do) which can provide both horizontal, vertical, and station information and be 'extruded' upon by a given typical section to produce a corridor.
-
as long as civil surfaces are defined under the constraints of a TIN model, 2D+(some Z's only) is about it.
" a set of contiguous, non-overlapping triangles" doesn't allow for overhangs or verticals
-
Haha
The concept of having a 2D Alignment and 2D Profile designed within the confines of a 2D Profile View, which combined, represent a 3D Vertical Alignment, leaves a lot to be desired.
Especially, as compared to that of a single 3D entity (NURBS? I 'spose Feature Line will do) which can provide both horizontal, vertical, and station information and be 'extruded' upon by a given typical section to produce a corridor.
It can be done using standard autocad 3d primitives...the disillusionment is when the stock c3D tools fail miserably.
However after seeing why and deconstructing how it failed, the trick was derived from the failure.
-
as long as civil surfaces are defined under the constraints of a TIN model, 2D+(some Z's only) is about it.
" a set of contiguous, non-overlapping triangles" doesn't allow for overhangs or verticals
Oh yes it does,...I can show you both tunnel and overpass models made from those pesky limiting triangles.
-
cool, post an example. My (limited) understanding of the triangulation model used tells me that a single TIN surface can't overlap or overhang. Would love to find out i'm wrong.
-
cool, post an example. My (limited) understanding of the triangulation model used tells me that a single TIN surface can't overlap or overhang. Would love to find out i'm wrong.
see here http://www.theswamp.org/index.php?topic=49902.msg550863#msg550863 (http://www.theswamp.org/index.php?topic=49902.msg550863#msg550863)
-
I'm not seeing any overlap or overhang in that drawing.....
-
It would be more apparent in a tunnel instance.
However part of the 'trick' is to not create surfaces that overlap....
even with the loop the loop there is a trick to create surfaces with no overhangs or overlaps
and to compensate for alignments not wanting to double back on themselves stationing-wise
Oh and creating the points along a 10X vertical scaled circular profile...
-
Not looking for anything specific to Civil3D, but the concept of TIN or similar procedural triangulation in general being applied.
-
Not looking for anything specific to Civil3D, but the concept of TIN or similar procedural triangulation in general being applied.
What is it you are interested in knowing?
-
well, how about a klein bottle...
-
well, how about a klein bottle...
autocad...or 3d max, or even blender
-
Given a generic set of point data describing an arbitrary surface including an overhang or dead-end tunnel, how would we go about constructing a triangulated surface? Further, how would we go about it with a through-tunnel? We can do so with a more limited arbitrary set of data which doesn't include any overhangs, tunnels, or similar features.
-
...
-
Given a generic set of point data describing an arbitrary surface including an overhang or dead-end tunnel, how would we go about constructing a triangulated surface? Further, how would we go about it with a through-tunnel? We can do so with a more limited arbitrary set of data which doesn't include any overhangs, tunnels, or similar features.
you might have to push that rough RECAP first...and then bring in the point cloud and then make surface from that.
a sample of this random point data would help explore methods / against desired outcomes
-
...
now, show me that in a C3D TIN instead of Acad surface mesh
-
...
now, show me that in a C3D TIN instead of Acad surface mesh
not sure IF I can... there might be some way to force it....might be,,,,
only I don't know who would ever approve building such a roadway...except maybe Werner Heisenberg
-
...
now, show me that in a C3D TIN instead of Acad surface mesh
Without the Civil3D, at least. There was a point up-thread about triangulating something; I'd be satisfied with a much simpler sample set. I'm interested in the procedure if somebody was thinking about one, not where Civil3D would fail in the task. Or was there just spit-balling about how it "should" be possible?