Author Topic: Prep. iSense 3D-scan via Meshmixer for "Shapeways" -> NoLuck  (Read 3556 times)

Persverre

  • Newbie
  • *
  • Posts: 6
    • View Profile
Prep. iSense 3D-scan via Meshmixer for "Shapeways" -> NoLuck
« on: September 29, 2015, 08:39:03 PM »
I've 3D-scanned "Grete and Carl Fredrik" (se pic) with my iSense (/iPad) and now want to print. The model is UV textured.
 
Process: iSense (*.obj) scan data -> Import to Cinema 4D -> Sculpt and Body Paint retouch. Save *.c4d -> Import to "Polytrans" for conversion of *.c4d -> Export from Polytrans to *.obj -> Import to Meshmixer for thickness/"escape hole"/etc.
 
I've been at it for a couple of weeks in Meshmixer. I feel I know it (somewhat) well now -> However - No luck...
 
When boolean for hole I f.ex. get problems with the UV texure. I do not seem to be able to get a thickness either?
 
Anyone care to take a look? The *.obj model - the *.mtl and the *.jpg texture is here (7MB ZIP):
https://secure.logmein.com/f?00_.K2-OTXBFbUEJO5LX49NTlKN6uBNvnmTxK1aYkDb
- or via link here in the post.
 
If you manage to get this to work please tell me/us HOW...!
 
Persverre


MagWeb

  • Administrator
  • Hero Member
  • *****
  • Posts: 1123
    • View Profile
Re: Prep. iSense 3D-scan via Meshmixer for "Shapeways" -> NoLuck
« Reply #1 on: September 30, 2015, 03:57:23 AM »
The Hollow issue most likely is due to the small size of your model. It's only about 6.8 x 6.8 x 7.8
If you'd set the unit "mm" (default) Hollow tries to create a thickness of walls of 2mm in its first run. This can't give some wall for this value creates a solid.

Several options to fix:
- Scale up your model using EDIT/UnitsDimension
or
- Change the unit (e.g. from mm to cm)keeping the values the same. On cm Hollow creates a thickness of 0.2cm by default.
or
- still using mm: reduce OffsetDistance after the first run in the Hollow tool (e.g 0.2) and run UpdateHollow.

Doing it some way as explained also GenerateHoles works fine here.

Can you provide some image about your problems with UVs doing some boolean?
I'm just a user as you are. Being no Autodesk employee: I do not know where this road will lead to, nor do I claim to've all stuff got right.

Persverre

  • Newbie
  • *
  • Posts: 6
    • View Profile
Re: Prep. iSense 3D-scan via Meshmixer for "Shapeways" -> NoLuck
« Reply #2 on: September 30, 2015, 06:45:27 AM »
Thank you very much - Simple as that! - Fixed by rescaling model to 10x dimensions. Hollow works.
 
However - Tried to order print at Shapeways via Meshmixer -> "Print" - The model is presented on screens without the texture? Please refer enclosed screengrab. What gives?
Has something to do with separate shells/surfaces, or/etc?
 
Persverre
 
(PS - As for mentioned UV-texture problem: My bad. Texture changed while trying "Solid" - And while trying boolean on the tiny, solid model: Underside.)

MagWeb

  • Administrator
  • Hero Member
  • *****
  • Posts: 1123
    • View Profile
Re: Prep. iSense 3D-scan via Meshmixer for "Shapeways" -> NoLuck
« Reply #3 on: September 30, 2015, 07:29:01 AM »
You've to transfer texture to per-vertex-color:
(Make sure to have surface color rendering on > the blue sphere in the Hotbox should be dark)

Run EDIT/MakeSolid. After its first default calculation set Type to accurate, ColorTransfer to Automatic. The better, higher SolidAccuracy and MeshDensity the better the transfer's result will be. Click Update and finally Accept.

Make the solid result the active object and pass it over to PRINT.
As soon as you select the full color material in Shapeways your model should turn colored...
I'm just a user as you are. Being no Autodesk employee: I do not know where this road will lead to, nor do I claim to've all stuff got right.

Persverre

  • Newbie
  • *
  • Posts: 6
    • View Profile
Re: Prep. iSense 3D-scan via Meshmixer for "Shapeways" -> NoLuck
« Reply #4 on: September 30, 2015, 09:08:13 AM »
> the blue sphere in the Hotbox should be dark - Oh...? Sorry - I lost you there. "Hotbox"?
 
I still tried to perform the rest of your suggestion - hoping that the setting is right.
 
And then -> WHAT? - Is that the resolution I get? That is terrible! And the texture/vertex-coloring is darkened? And shiny? Please check the screengrab showing "before" - and a copy model "after".
 
I shall try to increase the poly-count (which is already at 200,000) and try again - The + and - polygons is an impressive feature in Meshmixer BTW.

But "Hotbox"?

Persverre

MagWeb

  • Administrator
  • Hero Member
  • *****
  • Posts: 1123
    • View Profile
Re: Prep. iSense 3D-scan via Meshmixer for "Shapeways" -> NoLuck
« Reply #5 on: September 30, 2015, 10:08:08 AM »
You can access some dialog called the Hotbox if you press Space at your keyboard. While Space is pressed you can set some options.
The darker buttons are the active ones... for further information see my paper "UI Basics II"

Per-Vertex-Color means each triangle vertex "carries" a single color information. the color between, on the faces are blended only between. Against that using a Texture each triangle "carries" a snippet of the texture image. Meaning that in case of a texture also a low poly model looks nicer. You've to transfer this texture  to per vertex color for your Shapeways Z-printer (which you choose selecting that material) can only handle that kind of information.

The denser your mesh on the MakeSolid object is the more vertices you have to describe your former texture by vertices (in case of per vertex color vertices act as some kind of 3D pixels). A MakeSolid SolidAccuracy of 128 creates 3D grid of 128x128x128 cells. Each cell intersecting the surface will result in a vertex. So if you look onto your model from a certain point of view you've got a image resolution of max 128x128 which is pretty poor.
Raise SolidAccuracy and MeshDensity to the sliders' max (you can even get higher values by dragging over their limits WHILE moving the mouse slightly up or down) and you'll get better transformation of texture to per vertex color.

Don't worry about the dark or glossy shading- that's due to the default phong shader material. Once you've transferred texture to per vertex color you may try any shader material and drag it onto your model to visualize the actual color.

I attach an image of a result at 512 using the attached shader material (you may download it, click on the Plus icon in SHADERS and browse to the downloaded file. Now this is copied to your material library and you can drag it onto whenever you like)

« Last Edit: September 30, 2015, 11:44:31 AM by MagWeb »
I'm just a user as you are. Being no Autodesk employee: I do not know where this road will lead to, nor do I claim to've all stuff got right.

Persverre

  • Newbie
  • *
  • Posts: 6
    • View Profile
Re: Prep. iSense 3D-scan via Meshmixer for "Shapeways" -> NoLuck
« Reply #6 on: September 30, 2015, 10:41:13 AM »
WOW -- What an eye-opener! I'm sure there are others out there who also needed this. How can I thank you? - I was about to give it up.--
 
I'm not quite sure about the last parts you write about the download - There is a file "whitefluff.png" and the "result.jpg" - The last one I guess is showing a higher res result of the solid-procedure I'm now going to try.  The whitefluff.png escapes me.

Thanks again (a million) for your time!

Persverre

(PS - On my machine the Hotbox appears with "Spacebar" - Not "Enter")


MagWeb

  • Administrator
  • Hero Member
  • *****
  • Posts: 1123
    • View Profile
Re: Prep. iSense 3D-scan via Meshmixer for "Shapeways" -> NoLuck
« Reply #7 on: September 30, 2015, 11:43:05 AM »
Oups... sorry about the Enter.... of course it's Space - I'll edit the post above for other readers.

Yes, result.jpg shows a result with higher MakeSolid settings.

Whitefluff.png is a shader material you might try to add to your shader library to see vertex color on a white base.
I'm just a user as you are. Being no Autodesk employee: I do not know where this road will lead to, nor do I claim to've all stuff got right.

Persverre

  • Newbie
  • *
  • Posts: 6
    • View Profile
Re: Prep. iSense 3D-scan via Meshmixer for "Shapeways" -> NoLuck
« Reply #8 on: October 01, 2015, 04:49:11 AM »
Thanks for your help, and here is a final question:
 
 Do you know the DPI you get on f.ex. at Shapeways when printing Multicolor?

Knowing that  - and thanks to the "lecture" you gave us above - I could match my vertex value with the DPI to
get an optimal output - Depending on the size of the 3D print.

Persverre

MagWeb

  • Administrator
  • Hero Member
  • *****
  • Posts: 1123
    • View Profile
Re: Prep. iSense 3D-scan via Meshmixer for "Shapeways" -> NoLuck
« Reply #9 on: October 01, 2015, 05:57:56 AM »
Hmm, an optimized resolution (besides the printer's abilities) also depends on the layer height Shapeways uses.
Searching for that I found this helpful page:http://www.shapeways.com/materials/full-color-sandstone < seems they print at 0.4mm in Z?

BTW I found that they also support true texture if you use VRML97 or X3D format. PRINT instead sends STL format (therefor you need per vertex color) but if you'd export your model without being in PRINT you also have the option to export as a VRML with texture (Also Meshmixer isn't able to import that format back).
See:http://www.shapeways.com/tutorials/exporting_to_vrml_and_x3d_for_color_printing

Stagwolf already reported success that way:http://meshmixer.com/forum/index.php?topic=1874.msg4400#msg4400 maybe you contact him.
I'm just a user as you are. Being no Autodesk employee: I do not know where this road will lead to, nor do I claim to've all stuff got right.

Persverre

  • Newbie
  • *
  • Posts: 6
    • View Profile
Re: Prep. iSense 3D-scan via Meshmixer for "Shapeways" -> NoLuck
« Reply #10 on: October 01, 2015, 06:26:53 AM »
You are a real GEM, MagWeb. Thanks alot!