What do you do with cloth in extreme position of pJCM?

What do you do with cloth in extreme position of pJCM?

For example in pJCMShldrDown_40_L
in this pose, the cloth near the armpit is basically entering the body, where in dforce could result explosion.
Is it something that just need to be accepted, that in this pose, the cloth is impossible to be fixed?

 

Comments

  • crosswindcrosswind Posts: 6,961
    edited November 18

    In practice, it is acceptable ~~ Most of the vendors don't fix corrective morphs with pJCMShldrDown_40_L / R or body_cbs_upperarm_z40n_l/r because it's not really necessary.

    As for simulation, in practice, the mesh shouldn't explode as there's no abrupt intersection but just a "push-in". In case there's an explosion because of this, then fix it with other options, case by case...

    Post edited by crosswind on
  • MadaMada Posts: 1,989
    edited November 18

    I always fix mine. I'm pretty sure clothing wouldn’t pass QA at Daz if it visibly shows the body when the arms are lowered. :)

    I export the OBJ in the posed position, adjust/fix it in a modeling program, and reimport it using reverse deformation.

    Leaving it unfixed means you’ll always need to use *Start Pose from Memorized Pose* to avoid explosions. Simulating from a pose instead of zero pose can create unique effects which I often prefer to the full simulation from zero pose... the cloth often has a better drape.

    Post edited by Mada on
  • JamesJames Posts: 1,042
    edited November 18

    Okay.. mmm so how do you fix it, even the area near arm pit pushed into it's own body, causing  the cloth also to pushed in.

     

    Post edited by James on
  • crosswindcrosswind Posts: 6,961
    edited November 18

    Yea, some veteran PAs like Mada always fix them. Depending on the cases, as long as the clothing comform well to the figure and + Smoothing Modifier, there won't be "visible issue" with such a pose.

    However, I sometimes fix them in Blender, by using Smooth / Draw / Grab brushes as well as a Mask (with well-set material zones), and fixing from "inner side" is needed, e.g. the below example.

    Fixing it by using dForce is also doable but you will have to add a weight node to limit the geometry to that armpits area for simulation.

    SNAG-2024-11-18-012.png
    2016 x 1293 - 1020K
    Post edited by crosswind on
  • MadaMada Posts: 1,989

    I use the move tool in Modo to fix the mesh, grabbing the polygons and moving them into place. If I use the smoothing modifier I will set it to not collide against the figure because it can cause unexpected issues and make it even harder to fix in a modeler (when the mesh is squished between the body and the arm it can really get distorted)  and also with rolled edges/trims pushing through the outside of the cloth because its closer to the figure and pushed a different amount as the mesh further away from the figure.

    If you find it challenging to do the full morph in one go, you can do them incrementally... - bend the arm half way, fix that, import the morph, dial it up and pose the arm to the full bend, then export with the morph active. Delete the halfway morph from the clothing. Fix the morph on the full bend and import :)

  • JamesJames Posts: 1,042

    Hmm... could you give me a screen shot how an already fixed cloth near the arm pit supposed to look like...
    I don't understand.

    I already know how to use Blender with the sculpt. I just don't understand the "correct" or acceptable fix looks like.

  • MadaMada Posts: 1,989
    edited November 18

    Basically you want a sleeve to be outside the arm, and the torso part to be outside and not inside the figure.


    Image 1: View from inside the body (with smoothing turned off) the arm will be inside the body and the sleeve will be outside the arm

    Image 2: Arm bend down, no poke throughs on the torso

    Image 3: Doing it that way will avoid poke throughs when you have the arm forward and bend down - in this image the arm is bend 30 and front back 95

    SleeveFittingArm.jpg
    722 x 848 - 136K
    SleeveFittingArm2.jpg
    638 x 961 - 138K
    ArmFrontBend.jpg
    707 x 601 - 110K
    Post edited by Mada on
  • JamesJames Posts: 1,042
    edited November 18

    Ah... so it's okay for the sleeve to go through the torso.
    it's okay for the sleeve geometries around the arm pit to intersect with the cloth geometries around the torso.
    As long it still looks good from the outside.

    Mmm... what do you think  about using Marvelous Designer to perform the extreme pjcm and use the result as the correction.
    The reason why ask this, because when using MD to perform it, the geometries that get changed often not only the respectable side/area, but also the other side or other area.
    So later in daz when two arms doing extreme pJcm, I wonder would that be a problem.

    Post edited by James on
  • MadaMada Posts: 1,989

    I thought the same when MD came out but personally I prefer using a modeler to fix JCMs. The problem with MD is you have to isolate the areas to only drape where the JCM needs to be fixed. If you drape the whole garment and bring that into the JCM, and then add another JCM and another and they all drape the whole outfit you end up with a hot mess when they all activate at the same time. So to use MD to fix JCMs, pin all the polygons except the area where you need to fix :)

  • JamesJames Posts: 1,042
    edited November 18

    One more question. I've tried making multiple layers of clothing.
    When dforced, often they exploded.
    Do you have any tips to handle such cloth?
     

    Post edited by James on
  • crosswindcrosswind Posts: 6,961

    Not suggest use MD to fix such pJCM / cbs because you have to use a Morph Target... If you Pin the mesh before importing Morph Target, you'll get wrong simulation result as the pinned mesh won't drape at all when simulating with the imported Morph Target. If you Pin the mesh after loading Morph Target, you'll have to mostly rely on dragging which almost has no diffrence from fixing it in Blender... let alone you may not get good result.

    Then if you mean making double-layered garment... it's not really necessary in DS but if you do need to make one as well as with dForce ready, the inner layer better be set as a a dynamic surface add-on.

    If you mean making a couple of garments that'll be treated as multiple layers on dynamic surfaces, I rarely see explosions with such a case as long as there's no / less abrupt gemetry intersection... so better show the case.

  • JamesJames Posts: 1,042

    mmm... not double layered garment... more like for exampe, a dress and then a coat.

  • MadaMada Posts: 1,989

    For layers make sure there's enough space between the layers so they don't touch. If they intersect they will explode. Keep in mind that intersection isn't just based on physical location of the meshes. The Collision Offset setting also plays into it. If your meshes are not touching but still fall within the collision offset (0.2 is the default, which is actually pretty substantial) then you are colliding and it will have problems. There is a really cool feature in DS for detecting this.

     

    image

  • ProtozoonProtozoon Posts: 554

    Mada said:

    ... There is a really cool feature in DS for detecting this.

    Oh that is awesome!

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