Sketchup is a great resource for all kinds of shapes and fast modelling!
But i some serious problems deailing and converting them the geometry
Can Blender repair these kind of 'not watertight' surfaces? @yorik
testing this Watchtower designed by Santiago Calatrava
https://3dwarehouse.sketchup.com/model/72ff57bddc1513a480c90c65da5eb57d/Bilbao-airport-ATC-tower
One other practical question: How to set the zoomfactor less big of the scrollwheel in Blender?
I use Collada (DAE) format to transfer between Sketchup and Blender. Then in edit mode (hit tab) merge vertices by distance (setting the distance to some low value), then you can see where the holes are by selecting all the 'non-manifold' edges. You may have to build some faces to fill holes and/or correct the normals.
Can I ask a question? Sketchup geometric modeling paradigm is based on NURBS (B-Splines)? Or something hybrid? If not why do you think it's "a great resource for all kinds of shapes and fast modelling!" :)
Sketchup is simple mesh. I teach it to my students (less and less because they are making the free version lees and less capable) because it is relatively easy for them to get started with. Use the pencil tool draw some lines as soon as the lines create a planar surface it creates a plane. As soon as you have a plane push/pull it to make a 3d object. Group the object to move it as a unit. No primitives no splines, no curves. Stupid and limited but easy to start.
@magicalcloud_75 I have found to get the scroll wheel/orbit to work you need to select something that you want to orbit/scroll relative to and press the . (period) key on your number pad to zoom/focus on that element.
Yes easy to start and flexible! Focussed primarily on Geometry. Like CAD. But in a other way .. (.. thats why @ReD_CoDE ),.. so it NEEDS good conversion techniques, both to and from CAD. Not doing that thing called bim here. For my sample file: I spotted some trouble spots in the definition. However, i don't know how 'fill holes' or 'merge by distance' can help. I would think this also need extra modelliing techniques to fix the planes and get rid of these . I am learning along the way. Found out the use of SHIFT and CTRL :)
And this is repairing 3Dfaces in CAD that i would like to avoid..
I'm not sure, however, it seems that there's a commercial addon on Blender that maybe solve this obstacle, called MESHmachine
Sketchup also has an extensive asset library. Here is a video on how to get them into Belnder. https://www.youtube.com/watch?v=OqWn12IudfA&t=193s
I don't know what has happened to this plugin- https://www.youtube.com/watch?v=1YZdrBp2dJE
Yes yes probably all possible and fixing wise commercial intressting .
But I was exploring the route what Blender out of the box can do to fix my none watertight trousers :P
MY goal is to get SOLIDS at the end of the day.
https://forum.bricsys.com/uploads/editor/hj/79d7rnwue3ic.jpg
@magicalcloud_75 yes, Blender out of the box can fix non-watertight meshes. There can be many reasons why a mesh isn't watertight - from unwelded vertices, to non-manifold edges, to regular holes. Unwelded vertices can be fixed with selecting all in edit mode, and merging by distance. Non-manifold edges have been explained. Regular holes can be spotted with backfacing enabled. There is also a 3D print panel you can enable in the settings->addons menu (it is out of the box, no need to download anything) which does watertight analysis.
If you'd like, we can organise a screensharing session where I can guide you through the cleaning process. All the features are in Blender, just takes a little time to learn where they are :) You can catch me online on IRC ##architect channel on Freenode.
Thank you for the offer @Moult ! That is most kind. The DWG CAD software i use doesn't give me the flexibility to work out these flaws in surfaces. I repaired the top in this and attached it as ifc4 export. The software still tells me it isn't watertight but i cannot see any spots left. So i need more advanced techniques. Also, the rouding is not really that pretty yet. I bet Blender can make this much better. At the end it would be awsome it it can be made a solid form shape to transfer it back. For construction documentation use (DWG).
https://drive.google.com/open?id=1PknkrcC1LuvlP8PWm2-DR9pF3xoPKz9j
@magicalcloud_75 try this attempt. The shape was incredibly messy, as it was created by a solid modeling program with no regard to proper topology. I strongly believe that if more people in the BIM industry used meshes instead of thinking everything needs to be modeled with solid extrusions, we'd have much better geometry, like other industries. Ah well.
The proper solution would be to remodel it with proper topology, but I wanted to see how far I could get with a mostly automated clean-up process (Blender's 3D print panel has a variety of clean-up functions). If this doesn't work, I'll show you an attempt with proper topology.
There was no solid to mesh translation in the ifc4 involved. It is a direct result of poor mesh resolution from Sketchup. Exact the same result as you import the DAE into Blender. The reason for wanting solids is that many functions depend on this as input. It can been seen as one step higher in the hierarchy of CAD definitions. I can't make properly drawings, determinate volume or prepare for cnc using meshed objects..
The annoying thing, when modeling in sketchup, is that you don't see your mesh topology. This usually helps to create poor geometry without the user knowing. It's something I like much in blender, you see the mesh subdivisions, and it's much easier to model well.
But there is basically always these problems with meshes, 1) there can be holes and 2) curves are faceted. I think closing holes is not too complicated, even freecad does it ;) but i'd like to try to find algorithms that can approximate curves from facets (and from there recreate cleaner solids).. They must exist somewhere...
@yorik they exist and are part of "implicit modeling" techniques, however, personally I think NURBS (B-Splines) are better than meshes, and for sure a hybrid approach that combines all advantages together is much more advanced than current solutions
Combination of B-Splines (T-Splines, unfortunately under the control of Autodesk) and Meshes and Solids
You can see the topology in sketchup if you have show hidden geometry on. (if I am getting the terminology right). @yorik let me make sure I understand what you are proposing.
When you bring a curved object into a mesh environment it approximates that curve by segmenting it. You are looking for an algorithm that reverses that. Takes a faceted shape, finds the curve that best fits it, and converts it to a curve?
Dion and Yorik and many think about this approach, which is good enough when "the majority" think about, however, ...
I mentioned this here: https://community.osarch.org/discussion/15/geometry-modeling#latest
Known workflow: Brep (NURBS) --> Mesh ((sometimes optimized) triangular or quads)
Mesh --> Brep is an opened issue
When some people talk about FreeCAD's disadvantages, one of them is "It always ends up as B-Rep"
@ReD_CoDE you can't just say "implicit" modeling is the solution, because meshes and subdivision modeling allows modeling of certain shapes that implicit modeling will never be able to model. Try sculpting a face, or any frieze of a heritage building, with NURBs or implicit modeling. Any claim that one particular geometry type is more advanced or powerful than another is a false claim.
Your claim that FreeCAD has a disadvantage because "it always ends up as a B-Rep" is false. FreeCAD is perfectly capable of producing solids.
I do a lot of elaborate curved structures, but I typically don't use nurbs because I'm always thinking about how I'm actually going to build the thing. So I resolve surfaces to meshes as soon as possible, and similarly I always resolve curves to sequences of fixed radius arcs.
Each software SHOULD find that who are their main users? So, FreeCAD is popular in which industries? If you ask me I say in PLM area than BIM area, and those who are work on fabrication, etc, so people compare FreeCAD with some software like Inventor, or Solidworks, etc NOT Revit, so for them, FreeCAD always generates B-Rep and less advanced "Solids"
Geometric Modeling field is a messy area, which anyone has her/his own view about things, and most of the time the views are "general and incomplete"
As we know "ALL KERNELS" are "HYBRID" but its "VITALLY" important to find their bases, the base matters more
So, implicit modeling is a term that refers to almost all paradigms that are using implicit features
This is a chart from 20 years ago, and I think it'd a good start to expand it and add all new techniques and paradigms, and classify software based on it to find which software is in which category?
https://drive.google.com/file/d/1-UU3AjZUpzFtuaqPAcN0Z_Tdjt7N7KiW/view
I don't remember who shared an image from an urban sculpture that had a simple shape that was better to use NURBS instead of Mesh in Blender to generate them
NURBS, B-Splines, has some disadvantages like it's computationally expensive to operate on NURBS models.
However, things change so fast!!!!!!
I can share tons of articles like this, and you can find too, however, I don't know it'd useful or not
Implicit Progressive-Iterative Approximation for Curve and Surface Reconstruction: https://arxiv.org/pdf/1909.00551.pdf
Some months ago I shared this video from BCon19, so how many of you realized what they were talking about? Nebulae? particles? point clouds? ...
This is why when you work on GIS and talk about some old-school things about point clouds or raster/vector data, are not interesting to me
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