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Baking normal maps

polycounter lvl 6
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MITVIZ polycounter lvl 6
Hi guys, i have an object to bake and  its very simple yet giving so much issues, its a baking test in 3ds max, when i use the project modifier to bake nothing really happens just a plain normal map btu when i select no projection i get a better result, is this kind of low poly model adequate to bake from this high poly? attached are also the results i get when baking

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  • musashidan
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    musashidan high dynamic range
    The low poly needs more geo. Add more topology where the silhouette has the most extreme changes. The normal mapping process isn't magical :smiley:  You should always ensure that the low matches as closely as is possible. The red indicates missed rays, essentially blank spots on the map where no data was captured.

    Also, read through all the stickies here. Every problem that can and will be encountered in this process is covered in great depth.


  • MITVIZ
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    MITVIZ polycounter lvl 6
    Thanks for reply musashidan, but what about the handle of the lamp? it closely matches the underlying geometry and nothing was baked in 3ds max
  • MITVIZ
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    MITVIZ polycounter lvl 6
    Here is a copy of the model if anyone wants to have a go, i know there has been many questions and answers on normals before but none specific to my issue, i guess everyone sees it their own way maybe

    https://www.dropbox.com/s/3bb43io33knwput/troy.max?dl=0
  • MITVIZ
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    MITVIZ polycounter lvl 6
    should the low poly object always be a little inside the high poly?
  • MITVIZ
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    MITVIZ polycounter lvl 6
    should there also always be some light in the scene?

  • musashidan
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    musashidan high dynamic range
    I'll try and take a look at the scene if I get a chance this evening.
  • MITVIZ
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    MITVIZ polycounter lvl 6
    Thanks, i have also now made a more matching object to fit the model but stil nothing, i have also updated the dropbox
  • MITVIZ
  • MITVIZ
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    MITVIZ polycounter lvl 6
    i find the issue mostly happens when baking with an object with many parts, i tried it with a simple tire object i downloaded and all was ok but as soon as it is baking from a high poly with many parts max doesn't render them properly
  • musashidan
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    musashidan high dynamic range
    I had a look at your file and there are a lot of basic things that you need to fix:
    1 - the Geo: first and foremost, you just simply need more of it. This isn't the '90s anymore, we can spare extra triangles! :) Especially on the top part, and the curved cutouts on the base of the handle. There just isn't enough edgeloops to capture the curves and you will get waviness(see sticky here)
    Also, the geo of the base handle needs cleanup(wet welding)
    The top part also has reversed normals. You need to flip/unify the mesh normals.

    2 - The UVs: these are not good enough. You look like you just did a default flatten mapping and left it at that. There are random seams all over the place. You need to spend time at this and go in manually and put the work in. UVs are very important for this whole thing to work. Also, your smoothing group splits need to match your UV shells wherever you require a hard edge.

    3 - Your transforms need to be reset. If you move scale or rotate a mesh at the object level, the transform will no longer be aligned to the world. Always get in the habit of resetting Xforms. Always. And collapse your stacks. You don't need it once you start baking. Save out a separate file before collapsing. This is generally good practice at every stage of a project.

    4 - Explode baking: you will need to do this for the object. It's very simple. Just save out a file named object_explode_bake.max(see last tip)>move any elements apart that will intersect one another and block raycasting(you can detach them and move them at the same time as the high-poly, and reattach when finished)>bake. Note: in Substance Painter explode baking is obsolete as it uses a naming system to achieve the same result.


  • MITVIZ
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    MITVIZ polycounter lvl 6
    aha, thanks for your help  @musashidan,
    i did a fast unwrap to just see if anything would work at all, i didnt want to spend time on it for a test, i can work on the uv mapping and put in the uv splits to match the actuall object splits. 

    i can reset all transforms that is ok and all more geometry but i hope i was aiming for a really lowpoly model but will add more

    soo, did the baking work any at all for you? i just got blue when i baked, i was expecting to see something

    seems everyone does this explode baking and just puts it back together in the end but i watched one tutorial in 3ds max called "3D Motive - Baking Normal Maps - Tips and Tricks" where the author doesn't use explode before bake, instead he assigns each object a different material ID to render out objects. Do you know about this? in the baking options of 3ds max it has an option called "hit only matching material ID"
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