Jump to content
3DCoat Forums

Import tool to create greebles (new version of Import tool)


Daniel
 Share

Recommended Posts

  • Moderator

Tutorial is made by Tinker.

(translated from Russian into English)

This short tutorial demonstrates features of the new version of Import tool.

As far as we'll work with Import tool we'll need greebles (small details that helps models to look more 'technical'.) It can be created in any application for 3D modeling, usually with a series of arbitrary extrusions. You can download greebles using link at the bottom of this tutorial.

To make your models look more interesting and unique you would probably want to create your own greebles. Details with angled surface look better than with parallel to horizon:

post-896-1250503696_thumb.png

For easier placing of details on a model create a contour for the detail (that's an object with a name “_negative” which excludes from the model automatically and leaves a slot for the detail.)

post-896-1250503726_thumb.png

It's important to turn on 'respect negative volume' in the Import Params tab to permit contour exclusion.

post-896-1250503770_thumb.png

Because of “negative volume” width is bigger than detail's width we have an interesting effect:

post-896-1250503836_thumb.png

There is a joint between the body and the object. The detail looks as if it stands right on its place, and the body looks as if it has a special slot for the detail. Such joints look good with ambient occlusion.

Here is an example of how would it look without that effect. Looks not so interesting, and also there is a problem that was caused by different curvatures of the body and the detail – the detail looks tumbled down (it wouldn't happen with negative volume).

post-896-1250503897_thumb.png

Negative volume shouldn't have the exact form as the body. You may change its form to get various effects.

post-896-1250503972_thumb.png

For this tutorial I've made a small set of details, they all have “negative volume” (it can't be seen on a screenshot).

post-896-1250503983_thumb.png

We'll also need a base to which we will attach all the details, of course if you don't want to attach it to a default sphere :-). The Import tool will also help us here.

With such a concave surface you can make facets on objects.

post-896-1250503992_thumb.png

Load an object using Import tool.

post-896-1250504006_thumb.png

In transform regime cut any shape from a primitive.

post-896-1250504020_thumb.png

You can also use frame for cutting but cuts made with Import tool looks more interesting than those made with a frame.

post-896-1250504031_thumb.png

It's time to detail the object. Load the greebles using Import tool. Use 'on pen' mode. Use '9' and '0' keys to rotate the brush.

post-896-1250504044_thumb.png

Well, that's all :-)

post-896-1250504058_thumb.png

Thanks for watching and good luck!

Greebles: objects.zip

  • Like 1
Link to comment
Share on other sites

  • Contributor
I don't understand. None of the obj files in the folder have a _negative extension. I would like to know how to make my own...

Euh....yeah,actually they have a _negative extension but inside the .obi file.

When I open turbine1.obj in max for example and choose multiple object option I get two objects

named: objCylinder and obj_negative.

Its easy in 3dsMax just name your subobjects like that and save as .obj with group as object option on.

Link to comment
Share on other sites

  • Advanced Member
Euh....yeah,actually they have a _negative extension but inside the .obi file.

When I open turbine1.obj in max for example and choose multiple object option I get two objects

named: objCylinder and obj_negative.

Its easy in 3dsMax just name your subobjects like that and save as .obj with group as object option on.

Thanks, that works. This is a great feature :D

Link to comment
Share on other sites

  • Moderator
Thanks. How do I make my own 'negative volume'? That's unclear.

M

I'll try to make it clear :)

Steps:

1) Open your 3D app (I used Wings3D).

2) Make a detail (greeble). I got this:

post-896-1250586357_thumb.png

3) Create another object in the same scene (that oblect will be 'negative volume'). I got this:

post-896-1250586370_thumb.png

As you can see the detail locates inside the capsule ('cause I'm gonna use capsule as 'negative volume'):

4) Rename the second object (capsule in my case) as you like BUT (!!!) add "_negative" in the end. I had this:

post-896-1250586688_thumb.png

5) Export in Wavefront (.obj) format.

6) Do everything as Tinker explained. And... enjoy the results:

post-896-1250586390_thumb.png

Hope that helps :)

Link to comment
Share on other sites

  • Advanced Member

Ok I misunderstood the negative function. I thought we can create negative voxel layers inside 3dc and they would be negative booleans in the scene and we can toggle them on or off incase we change our mind about boolean details like grooves, etc.

Link to comment
Share on other sites

  • Contributor
Ok I misunderstood the negative function. I thought we can create negative voxel layers inside 3dc and they would be negative booleans in the scene and we can toggle them on or off incase we change our mind about boolean details like grooves, etc.

This 'boolean' operation can be performed by subtracting one volumes content from another volumes content.

Link to comment
Share on other sites

  • Contributor
Hmmm, but as taros said, how do you retopologize something like your example?

I don't know the Taros reference but the example above would probably be best done by retoping seperate objects and merging them together where necessary after retopo.

Link to comment
Share on other sites

  • Advanced Member

Hi All,

I have just tried this new merge-option. While it worked nicely I wondered - why is the second object necessary when only a shadow-catching cavity is desired?

I believe - at some point there could even be an even simpler and quicker workflow:

  • The user takes an arbitrary mesh and places is in the scene while still in preview state
  • next we would determine the desired Offset distance with a spinner or a on screen widget (3DCoat would draw a wireframe preview)
  • and when we press Apply 3DC creates an on the Fly Mesh Offset/boolean operation

This of course would only work if the user wants a cavity which equals an exact offset "negative copy" of the merged object.

But in all these cases one could take whatever mesh without first having to define a Cutter object in the same file. To me this seems so obvious

that I wonder if I must have missed something...

Link to comment
Share on other sites

  • Advanced Member
Far not every mesh allow such operation on the fly. Manual way better anyway - no lags, full control.

Why so? Self-Intersections? The meshes you posted at least should do.

Well - I personally won't see not much of a need for this special merge mode for my work anyway

but I thought I should post this comment :)

Link to comment
Share on other sites

  • Contributor

Several reasons. Self intersections, yes. Then just mesh structure. Auto offset could be used only on very regular mesh without naked seams, lots of triangles (such drowbacks could be on mesh exported from nurbs, etc). Then caverns in the model, you dont want to fill. And dont forget the speed.

This detail for example couldnt be offseted on the fly bcos of every of this reasons

post-1407-1251117911_thumb.jpg

As for instrument itself. Well... only tool you actually need to make 3d is a notepad to enter vertex coords in .obj file. All other software invented just only for speed, usability and quality improvement.

Link to comment
Share on other sites

  • Advanced Member
Several reasons. Self intersections, yes. Then just mesh structure. Auto offset could be used only on very regular mesh without naked seams, lots of triangles (such drowbacks could be on mesh exported from nurbs, etc). Then caverns in the model, you dont want to fill. And dont forget the speed.

This detail for example couldnt be offseted on the fly bcos of every of this reasons

post-1407-1251117911_thumb.jpg

As for instrument itself. Well... only tool you actually need to make 3d is a notepad to enter vertex coords in .obj file. All other software invented just only for speed, usability and quality improvement.

Hmm.

I believe naked seams are generally problematic as 3DC can not merge open objects.

Triangles: Offsetting these should generally work. The question is also if objects are still treated as a mesh when

being offset or already as Voxels. If the latter is the case even Self-Intersections might not be necessarily be a problem.

I see your point with the cavities however.

As for instrument itself. Well... only tool you actually need to make 3d is a notepad to enter vertex coords in .obj file. All other software invented just only for speed, usability and quality improvement.

Weird statement. All I wanted to say that I personally don't use 3DC in a way which needs complex looking Details in the way you describe in your tutorial.

I did not say that the tool itself is useless for other people.

Link to comment
Share on other sites

  • Contributor

Ok, i see your point. Anyway, dont forget about speed. 3DC use only mesh, not phong shading, so all rounded detail rather heavy, so offset will take some time, slow down work speed. It contradict greebling concept as fast tool. When modeling greeble you could make offset for it with several clicks and never spend time on calculations.

Link to comment
Share on other sites

  • Carlosan changed the title to Import tool to create greebles (new version of Merge tool)
  • Carlosan pinned this topic
  • 3 weeks later...
  • Carlosan changed the title to Import tool to create greebles (new version of Import tool)

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

 Share

×
×
  • Create New...