Artifacts on imported MDD animation

edited December 1969 in Carrara Discussion

Hello,

I've been experimenting with creating cloth animations with Marvelous Designer and importing them into Carrara using Fenric's MDD plugin, but I am seeing some artifacts on the imported MDD figure that are not present when I only import the obj file normally. See attached image for artifacts (MDD figure on the left, obj file on the right). Has anyone seen anything like this before?

Comments

  • FenricFenric Posts: 351
    edited December 1969

    No, I haven't seen anything quite like that.

    Do the marks persist throughout the animation, or do they go away after the first frame?
    If you apply one step of smoothing to the object, do they go away then?

  • mjc1016mjc1016 Posts: 15,001
    edited December 1969

    Looks like flipped normals to me...

  • edited December 1969

    They remain throughout the animation, and are fixed in relation to the mesh (i.e. they don't move around). And yes, I thought too that it looked like flipped normals.

    Tried loading the same file into Blender 2.49b; was kind of hard to tell because I couldn't get the smoothing working too well, but it didn't seem like the artifacts were present there.

  • mjc1016mjc1016 Posts: 15,001
    edited January 2013

    They remain throughout the animation, and are fixed in relation to the mesh (i.e. they don't move around). And yes, I thought too that it looked like flipped normals.

    Tried loading the same file into Blender 2.49b; was kind of hard to tell because I couldn't get the smoothing working too well, but it didn't seem like the artifacts were present there.

    Try Blender 2.6x...it seems to handle smoothing and triangles much better....since it looks like the mesh is mostly triangles. Also duplicate/unwelded vertices can, at least, contribute to the problem.

    I'm guessing that the actual export to obj both welds and orients the normals...

    Also, one of the clues that it may be normals...look closely at some of the displacement in the affected areas...it's reversed.

    Post edited by mjc1016 on
  • FenricFenric Posts: 351
    edited December 1969

    They remain throughout the animation, and are fixed in relation to the mesh (i.e. they don't move around). And yes, I thought too that it looked like flipped normals.

    Tried loading the same file into Blender 2.49b; was kind of hard to tell because I couldn't get the smoothing working too well, but it didn't seem like the artifacts were present there.

    I meant in Carrara: double-click the object, select all faces, and turn smoothing on.

  • edited January 2013

    Fenric said:

    I meant in Carrara: double-click the object, select all faces, and turn smoothing on.

    I tried that first, but the moment I double-click the MDD object (or try entering the model room), Carrara grinds to a halt...

    Post edited by benchrs_e1289c756c on
  • FenricFenric Posts: 351
    edited December 1969

    Fenric said:

    I meant in Carrara: double-click the object, select all faces, and turn smoothing on.

    I tried that first, but the moment I double-click the MDD object (or try entering the model room), Carrara grinds to a halt...

    How big is that mesh? Even Carrara doesn't like individual objects to be much over 100,000 polygons (and even that is way too dense for a dress).

    If it's not that big, it sounds like you might have mesh errors - isolated points, "T" shaped connections, or lines that aren't part of a polygon at all.

  • edited December 1969

    Fenric said:

    How big is that mesh? Even Carrara doesn't like individual objects to be much over 100,000 polygons (and even that is way too dense for a dress).

    If it's not that big, it sounds like you might have mesh errors - isolated points, "T" shaped connections, or lines that aren't part of a polygon at all.

    The obj file itself is about 24,000 polygons. It might have been the number of frames in the animation that it struggled with - managed to load a shorter mdd sequence. Subdividing didn't do much either (see attached).

    However, I tried exporting the same animation from Marvelous Designer as an obj sequence as well, then imported it into Carrara using the DCG importer, and everything looked fine.

    subdivided.jpg
    1280 x 480 - 45K
  • FenricFenric Posts: 351
    edited December 1969

    Fenric said:

    How big is that mesh? Even Carrara doesn't like individual objects to be much over 100,000 polygons (and even that is way too dense for a dress).

    If it's not that big, it sounds like you might have mesh errors - isolated points, "T" shaped connections, or lines that aren't part of a polygon at all.

    The obj file itself is about 24,000 polygons. It might have been the number of frames in the animation that it struggled with - managed to load a shorter mdd sequence. Subdividing didn't do much either (see attached).

    However, I tried exporting the same animation from Marvelous Designer as an obj sequence as well, then imported it into Carrara using the DCG importer, and everything looked fine.


    If you can send a copy of the mesh to fenric (at) fenric (dot) com, I'll look into what the problem is.

  • edited December 1969

    Fenric said:

    If you can send a copy of the mesh to fenric (at) fenric (dot) com, I'll look into what the problem is.

    Mdd and obj file sent.

  • FenricFenric Posts: 351
    edited December 1969

    Fenric said:

    If you can send a copy of the mesh to fenric (at) fenric (dot) com, I'll look into what the problem is.

    Mdd and obj file sent.

    There are significant areas of reversed normals in the OBJ file. Carrara's OBJ importer is injecting creases (the dark blue lines) into the figure, which my importer does not do. If you remove the creases, then you get the same artifacts from an imported OBJ as the MDD importer does.

    objfile.jpg
    640 x 480 - 24K
    objfile0.jpg
    600 x 472 - 130K
  • FenricFenric Posts: 351
    edited January 2013

    The UV map is also out of bounds, extending far beyond the allowed range.

    I tried to do "align" with UVMapper pro, but it just flipped back and forth with different areas pointing the wrong way.

    You might be able to fix the artifacts by putting creases into the MDD imported object after the import. Your model did eventually open in the vertex modeller for me, though it took a few minutes.

    EDIT: If you select all, crease edges: all, then smooth edges: less than 50 degrees, then it won't have the weird artifacts anymore.

    Post edited by Fenric on
  • FenricFenric Posts: 351
    edited December 1969

    I apologize for the inconvenience, but if you wish to continue discussing this issue with me, you must go to http://carraracafe.com

  • 3DLust3DLust Posts: 230
    edited December 1969

    Hi Blackadder_no - if you send me the MD2 file I can try it out on my system for you and see if I get the same results. I've tried everything but I can't replicate the problem you are seeing.

Sign In or Register to comment.