Starting simple with color but failing

Discussion in 'General Discussion' started by CristobalGordo, Sep 17, 2011.


  1. I just wanted to upload a test color model- nothing complicated, no textures or anything. I imported an x3d model into meshlab, sprayed some color on it with zbrush then saved it as an x3d model. I got the rescaling problem that they warned us about so I shrunk it down by a thousand and it uploaded fine. Problem is, the color doesn't show up in the preview window. So is it colored or not? I tried other things- zipping it before uploading, making sure the faces were colored not just the vertices in meshlab. I'm probably missing something in meshlab.

    All I want to do is import a nice mesh into meshlab, throw a little color on it, upload it as a colored model, and see it with my own two eyeballs colored on my "my designs" page. I have to go this route because my CAD program doesn't export x3d or vrml2. Any insights? Thanks.
     
  2. stop4stuff
    stop4stuff Well-Known Member
    aeron203 created a tutorial specifically for sketchup & meshlab, but the meshlab portion & file editing section should work out ok for you.
    see; https://www.shapeways.com/tutorials/textured_models_with_sket chup_and_meshlab

    A lot of issues with colour upload are in the colour image path name in the model file.

    If you are on a windows machine, Accutrans3D is pretty good at file conversions. It includes the functionality to be able to truncate the image filename as well as performing scaling upon saving.

    Hope this helps.
    Paul
     
  3. Specifically on the "Exporting to VRML and X3D for color printing" page it says,

    "'Per face' materials are easier to work with, but will give you less detail.
    UV texture maps can be very detailed, but require the careful mapping of the texture map to your object.

    To use 'per face' materials, simply apply material colors in your 3D application and export to VRML2. Then, jump to step 4 below to read how to upload your model. "

    That's what I would like to do- paint some surfaces in my model a solid color (no need for textures) and it would seem from the above that that is fairly straightforward to do. I'd love to hear from someone who has done this- uploaded a "per face" colored model successfully.

    On a possibly related sidenote, in scanning the first few hundred recent uploads I noticed that only three people had used color at all. Seems like if you could upload a vrml file with per face color info just like any other file there'd be a lot more almost by accident. Often I use color in the development process even though I know I'm just getting it in WSF in the end.
     
  4. stop4stuff
    stop4stuff Well-Known Member
    As long as you are using a Widnows machine, get yourself a copy of Accutrans3D from https://www.micromouse.ca/

    I already had the file save with coloured faces, checking my workflow for the below two methods only took 25-30 minutes total.

    Method 1: Converting face colours to UV map

    With Accutrans3D
    Load model
    Align normals on all layers
    Depending how many colours you have will be the number of layers, you may need to go through the list of layers one by one to flip normals
    Under the tools tab, click 'Convert layer colours to UV and texture' save the image file as a jpg
    Go file, save with options
    Selesct Save File Type as VRML 2.0 (97)
    Check UV, Texture Path and Partial
    Click use units, make import unit as millimeters and export units as meters (SW treats native VRML units as meters so the model needs scaling down to 1/1000 of it's original size).
    Click save
    Find the model and image file
    Create an archive zip file containing the image and model file
    Upload zip and wait for a bit for confirmation.

    Example of the above technique
    https://www.shapeways.com/model/335986/13900f0e77821287248c52 e08e29a88b/colour_police_phone_box.html

    Method 2: Saving model with face colours.

    Again with Accutrans3D
    Load model and align normals as above
    Save with options as VRML2.0
    Check Vertex colours and Vertex Normals, scale as above
    Click save
    Upload wrl file and wait for confirmations

    Example of this technique
    https://www.shapeways.com/model/335991/5e65eaedfe3a0d7faf588c 0043ad250d/colour_police_phone_box_vertex_face_colour.html

    Paul

     
  5. stop4stuff
    stop4stuff Well-Known Member
  6. OK I did "Normalize Vertex Normals" in meshlab and then again with the scaling- make sure your model is in meters and you choose meters when you upload and IT WORKED.

    Thanks you lead me in the right direction talking about the normals.

    Cool.
     
  7. Yes that was it. "Normalize Vertex Normals" in meshlab did the trick.

    Thanks again
     
  8. lensman
    lensman Well-Known Member
  9. Must've happened during the riots this summer in the UK.