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help with low poly mechanical modeling & texturing

polycounter lvl 18
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Justin Meisse polycounter lvl 18
I recently worked on a fairly complex low poly hard surface model and it was really difficult finishing it in a timely manner. Does anyone have any tips & techniques for "old school" low poly hard surface stuff, like robots & guns?

I'm looking into some xnormal map types (thanks Jason Young) to try and speed up the texturing process, a lot of the texturing time is eaten up with highlighting edges which can be a pain on a really greebley asset.

It should be mentioned that these are 1500 tris and less with no normal maps or high poly sculpts.

Here's one shortcut I discovered
I typically always bake my AO in 3DCoat, I found that a large number of lights with a fairly low blur bakes out a good AO for low poly mech stuff. I recently did 128 lights with 8 blur steps and it gives a bit of a subtle bevel look on hard, unbeveled corners

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  • Jason Young
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    Jason Young polycounter lvl 14
    Already told you, but thought someone else might find it useful. Sometimes I like to block things out using the brush setting "paint single polygons". That way it adheres to your poly edges and works well to block out the lighting values on planar faces.

    brush.jpg

    Also is nice if you've got something like a belt and you want to texture just the polys extruded out for the belt with a nice crisp edge.
  • nyx702
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    I'm not super experienced with this type of work but TexTools has a pretty nice render "worn edge" map as well as a hard edge map derived from smoothing group splits. Might be worth checking out.

    A super (sl)easy way I make worn edges in PS is using the hard round brush just quick and dirty paint the edges then run the "Splatter" filter on it. Ruffs up the strokes.

    Not sure if that is what you are looking for but maybe it helps.
  • InProgress
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    InProgress polycounter lvl 14
    I recently tried kitbashing my high poly mesh by using beveled primitives. The downside is that the high poly mesh will have terrible topo.

    A different way would be to properly make the high using sub-Ds, and the just remove most hard edge loops to drastically reduce tri count. As far as time saving goes, it depends on the model. It's sometimes easier to just build the low poly mesh from scratch. Hope it helps.
  • Justin Meisse
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    Justin Meisse polycounter lvl 18
    thanks for the tips, I just want to mention this is a no high poly workflow: no subdivision modeling or sculpting with textures painted in 3Dcoat + Photoshop. Ideally with a 4 day turn around or faster.
  • Michael Knubben
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    Even without a highpoly, bake those edges! Bake a curvature map with Xnormal/Substance Designer/Max/whatever. subdivbide the model temporarily if the edges don't come out right, but don't waste time painting that stuff yourself.
    edit: If speed is a concern, I'd suggest Substance Designer anyway, even if only to bake and process (blurring, contrast, overlaying some grime to break it up...) the curvature maps. Just get your Substance set up and you can just throw it onto every new mesh you make.
  • katana
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    katana polycounter lvl 14
    It doesn't sound like "fairly complex low poly" are words that should go together and as you are an accomplished modeller, I would be curious as to what method you used to break down the forms first?
  • Justin Meisse
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    Justin Meisse polycounter lvl 18
    MightyPea: yeah, I'm trying out xNormal, I just need to learn how to use it :P. Luckily there's no real need to add grunge to the edge highlights, it wouldn't match the art style. I'll mess with substance designer at home with the 30 day trial but I don't think I can convince the office to buy me a license.

    katana: As far as how I break down the forms, I model it out with primitives and then optimize things down. Cylinders may have to be dropped down to 3 sided or alpha cards and plenty of details will have to be painted in rather than modeled. I try to avoid too much intersecting geo because I have limited texture space, it can be a balancing act between what saves on triangles and what saves on UV space.
  • Psyk0
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    Psyk0 polycounter lvl 18
    Dunno if that'll help but...

    I've done a few batch of ships/assets that required the illusion of metal highlights, all started from a simple AO bake in max. I then used a greeble panel texture, that i manually detailed once in photoshop, adding highlights to get a metal effect. Once the greeble sheet was done it was simply overlayed on top of the bake, that took care of small details. Getting an interesting design was just a matter of rotating the greeble sheet around for each part of the ship.

    I also did a quick pass to "punch" the baked edges, just by holding down shift and tracing on top of the AO and blurring to fade highlights where needed. Last step was to create broad highlights for stuff like cylinders, oval shapes etc.

    That worked so well that i spent more time finding new silhouette designs than texturing the assets. That being said, it all depends on the style you're working with, if you need details that have to make sense up close, you'll need more time obviously.

    Can you show an example?
  • Justin Meisse
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    Justin Meisse polycounter lvl 18
    Psyk0: thanks, the greeble sheet is a good idea, alot of the large surfaces are very smooth and clean but I do have a lot of greebly machinery under the panels, a sheet of pistons and random greebly machinery will help out.

    I don't have an example I can show, I might work something up to test at home I just have to overcome the PTSD these last few assets caused! Luckily I'm doing a bunch of human clothing for the next few weeks so I don't have to worry about stressing out about it right now.
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