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curvedspace

Working in true physical dimensions

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There are a few things I am trying to understand with 3DC, and I am hoping for some quick answers that can get me going without too much searching.

The trouble I have been having is with absolute numbers (mm) at preferred resolutions. I want to import an obj or stl file at .05mm (voxel) resolution and I want to know its physical size (in metric) before I commit (voxelise) the mesh. I have spend considerable time looking for a panel that gives the physical size of meshes, either before importing or after, but have not been thus far successful.

True object size is very important to me since my interest is related to 3d printing. I want to import, move, scale, calculate stl reductions, and export my models in real world units. Percentages are usually not of great use to me. Do I have this option in 3DC?
 

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Hi curvedspace,

I can so totally understand you. I decided to buy 3dc some while ago because I am using FreeForm Modeling for even longer. There I define the size of the voxel for an object with a defined dimension. So I always know if my resolution is fine enough for the size of radiae my details will have.

In 3d-coat I just again spend hours with a friend where we tried to figure out how the ratio of voxels to volume is defined.

In the Sculpt room under the menu Geometry there is Define Measurement Units. It is set to Units = mm, Voxels per Unit = 1.000000 (is that 1 voxel or 1 mio voxels?) and a Unit Scale of 1.000000. Sadly there is no explanation to that. A Primitive Cube with 1m dimensions then results in 43 mio triangles. Even if we assume that 1 triangle is 1 voxel how do we reach this number? If all the settings are metric I would not expect such an odd number. As those are the surface triangles it should be 1 or 10 or 100 or some number like that times 6.

So much for the ranting.  ;)

What I would like to have is an explanation how 3dc handles the amount of voxels in the scene or objects and if there are some clear numbers which can help us figuring out the desired resolution.

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Hi Carlosan, I already thought about asking Andrew to change the manner how voxels are defined in 3dc, but since nobody else seems to find this cumbersome I guess they all have some secret way of defining their voxel density and might be able to give us a hint how they define the correct density here.

So far my understanding would be that the whole workspace is ´filled` with voxels in a size defined by the Define Measurement Units. But when I create a primitive, then change the units from mm to m in Define Measurement Units and create a new primitive the amount of visible triangles stays the same.

If I would know for sure the original scene voxel density then I could use the Res+ to prepare my voxel layer to roughly the desired density for my object to be imported.

As for the "just scale it during import to the desired resolution". This will cause different problems when importing multiple parts that should fit together.

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Geometry > Define measurement units doesnt help ?

 

The only way i can imagine is to add a rule as background > ref image

load an object with knowed size

match rule size to object

 

post-10142-0-24479000-1424254624_thumb.j

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Hi puntoit

I am glad you understand the issue, which has to do with productivity. I will have to try out the dialogue box in carlosan’s solution. Maybe it’s what I am looking for.

But the problem of space management in real units remains. I would like to import a mesh and define on the spot its desired dimension. I don’t think poly counts are helpful in this case, and even if a formula could be worked out, it would be cumbersome and time consuming. Especially since objects are continuously moved around and scaled as a design progresses.
 

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At version 12 some Menu names was changed

 

post-10142-0-88845700-1424285380_thumb.j

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PuntioI and I are going over new features for importing voxels objects with more exposed parameters. Once we are done, I will send Andrew though support our feature requests and add them at Mantis... I will post the mantis feature request link when I have made it.

These features would solve the problems discussed here in this thread. If Andrew can add them, that would be great. Of course it would have to be put on the development schedule so when It could be done, that is up to Andrew and his team.

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Great!

If I could add my input also, during import, and prior to voxelisation, some dimensions panel should display the physical size and global position of the imported mesh, and allow for resizing, scaling, rotating and adjusting the voxel density, before the mesh is committed.

 

Settings (particularly rotations) should be inherited so that objects can be set back to zero at any time later in the project.

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Great!

If I could add my input also, during import, and prior to voxelisation, some dimensions panel should display the physical size and global position of the imported mesh, and allow for resizing, scaling, rotating and adjusting the voxel density, before the mesh is committed.

 

Settings (particularly rotations) should be inherited so that objects can be set back to zero at any time later in the project.

We discussed all those areas.... :D  

When a Mantis Report is added, you can add any input you wish to the report in the note section...

Now I have no idea of what Andrew can do and can not do or desires to do. I will say though that Andrew has listened very close to those that use his software and has added lots of features requested by the community down though the years which are too many to list here.

Edited by digman

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what about the Measure tool in paint room ?

post-10142-0-08698700-1424311010_thumb.j

 

helps ?

 

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what about the Measure tool in paint room ?

attachicon.gifMeasure.jpg

 

helps ?

This is more about our import options and exposing the user to parameters that are available to the users in software like Freeform etc... Yes a few for after importing too.

Now whether it would mean heavy re coding of deep parts of 3DC, again I do not know. I am though going to put up the user request in the next few days or so...

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How the app could recover reliable sizes for a collection of models defined using scales with unknown correspondence to physical units ?

 

There is a paper, duno if can be developed on 3DC

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NETFABB: Measure, Check and Repair

3D_netfabb_logo.gif

This is a free program (basic version) that can edit STL files. It can open an STL file and then shows basic failures on a model. The program also has basic STL file editing features such as analysing, scaling, measuring, and repairing.

 

Netfabb_screenshot_resize.png

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Yep, I downloaded Netfabb basic once before and just got it again a few days ago.

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Need the same features that this software ?

 

netfabb Private Price: €239.00

netfabb Professional Price: 1.499

 

if Andrew can develop a competitive option , I guess 3DC can open a potential market . But I do not know if development time is justified.

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if Andrew can develop a competitive option , I guess 3DC can open a potential market . But I do not know if development time is justified.

 

This is where the industry is going. If you don't tacle it now, you will have to at some point. I say, go for it now and stay on top.

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We discussed all those areas.... :D  

When a Mantis Report is added, you can add any input you wish to the report in the note section...

Now I have no idea of what Andrew can do and can not do or desires to do. I will say though that Andrew has listened very close to those that use his software and has added lots of features requested by the community down though the years which are too many to list here.

Did you create the Mantis report by any chance?

Edited by ajz3d

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