How to generate a gloss map

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Optimus vertex
hi, is there a way to generate a gloss map, if thats what you call it? this is what i am talking about:



how can i easily generate this type of map and use it in a texture?

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  • Eric Chadwick
    Yes there is. Look up PBR on our wiki, and start checking out the links.
  • Optimus
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    Optimus vertex
    nope, couldn't find it.
  • pior
  • Optimus
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    Optimus vertex
    pior said:
    "easily generate"

    What does that mean ?



    what i meant to say was, i need a generator, to generate a gloss map, preferably something  i can use easily.
  • pior
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    pior quad damage
    Yeah, but that still doesn't answer the question - because we have no clue what you already can or cannot do.

    The texture above is *extremely* simple - it's basically a medium grey fill, with some slight variations for each element (probably planks ?) and a very light texture overlay. This takes about 15 seconds to create in Photoshop with just a very basic understanding of the program, which is obviously a requirement before diving into texturing.

    Therefore there is a very strong disconnect between what you ask (some kind of automatic way to "generate" ... something ?) and the example that you show, which is trivially simple.

    I'll reformulate. Generating it ... from what , exactly ?

    Also : if you are currently not comfortable with photoshop or image editors in general, focus on that for a while first.

    Lastly, a very important thing to consider :

    • User wants to do X.
    • User doesn't know how to do X, but thinks they can fumble their way to a solution if they can just manage to do Y.
    • User doesn't know how to do Y either.
    • User asks for help with Y.
    • Others try to help user with Y, but are confused because Y seems like a strange problem to want to solve.
    • After much interaction and wasted time, it finally becomes clear that the user really wants help with X, and that Y wasn't even a suitable solution for X.

    This is referred to as "the XY problem" and this is probably what you are running into at the moment. http://xyproblem.info/
  • Eric Chadwick
    Pior you're awesome. OP lost me at their 2nd post. Yet you returned here with a very solid reply.

    I want to be your student.
  • Optimus
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    Optimus vertex
    pior said:
    Yeah, but that still doesn't answer the question - because we have no clue what you already can or cannot do.

    The texture above is *extremely* simple - it's basically a medium grey fill, with some slight variations for each element (probably planks ?) and a very light texture overlay. This takes about 15 seconds to create in Photoshop with just a very basic understanding of the program, which is obviously a requirement before diving into texturing.

    Therefore there is a very strong disconnect between what you ask (some kind of automatic way to "generate" ... something ?) and the example that you show, which is trivially simple.

    I'll reformulate. Generating it ... from what , exactly ?

    Also : if you are currently not comfortable with photoshop or image editors in general, focus on that for a while first.

    Lastly, a very important thing to consider :

    • User wants to do X.
    • User doesn't know how to do X, but thinks they can fumble their way to a solution if they can just manage to do Y.
    • User doesn't know how to do Y either.
    • User asks for help with Y.
    • Others try to help user with Y, but are confused because Y seems like a strange problem to want to solve.
    • After much interaction and wasted time, it finally becomes clear that the user really wants help with X, and that Y wasn't even a suitable solution for X.

    This is referred to as "the XY problem" and this is probably what you are running into at the moment. http://xyproblem.info/



    like i do for my normal maps generator, i put in the photo i want to add bump to, and then i generate it. same thing goes for the gloss map, i want to take my normal photo, and generate a gloss map, no image editors..
  • pior
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    pior quad damage
    How could such an "generator" detect what is supposed to be glossy and what is supposed to be rough ?
  • Optimus
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    Optimus vertex
    thats entirely up to the devoloper, as far as i know, i just "generate" it.
  • SnowInChina
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    SnowInChina polycounter lvl 8
    by "generating" it, you define this stuff
  • pior
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    pior quad damage
    Textbook XY problem indeed :) I'll try one more time.

    Basically, it seems like you've noticed that many roughness/glossiness maps tend to have the kind of pattern shown in the example picture (slight variations in value, faint streaks, and so on).

    Therefore you are asking "how can I generate a glossmap ?" (that's Y).

    But when you mention the topic of gloss/roughness to people experienced in texturing, they take your word at face value. Therefore we are telling you : you can't generate data representing roughness and glossiness out of thin air. A generator needs input. Accurate gloss/roughness is based on what is dry and rough, and what is glossy and shiny. It is simply not possible to guess accurately from a single photo. It's not "up to the developper" - it's physics/optics.

    But what you are REALLY trying to ask is : how to generate this kind of pattern (that's X). This has no relation whatsoever with it being used as a gloss/roughness map. All you need to do is to search for Photoshop tutorials on how to create, say, concrete textures. Or look for grunge generators/filters. Or anything of the like.

    https://www.google.com/search?q=how+to+create+a+grunge+texture&oq=how+to+create+a+grunge+texture&aqs=chrome..69i57.4167j0j4&sourceid=chrome&ie=UTF-8

    Now of course, programs like Substance Painter/DDO can generate such patterns, as long as they are told what material they are supposed to generate. Even these advanced tools cannot automagically guess materials from photos. They need input.

    Overall, my advice would be for you to not touch any "generator" or any advanced tool like SP or DDO until you develop a better understanding of the topic as whole. This also requires a willingness to do things manually before looking for "generators."

    Good luck.
  • gnoop
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    gnoop polycounter lvl 7
      Nobody "generate"  normal maps  from a photo for pretty a while already   except for  a kind of  very hi frequency noise , 1 mm  of height amplitude.    And only  for the subjects where a photo is kind of similar to depth /height image (darker  pixels is deeper than brighter ones).       In fact any  crazybumped  normal maps are instantly recognisable  as  faked one , especially at tangent lighting,  and hardly seen in current games.

      A depth/height image  is a base of any texture nowadays.   Sculpted,  photogrammetry scanned, procedurally generated. You could  try  to turn a photo into the depth too manually masking/selecting certain areas.     Once you have a depth/height image you can "generate" both normal map and roughness/gloss map  considering an idea that prominent parts are usually slightly more polished than deeper ones and pixels in crevices  are never shiny.   it's a kind of oversimplification.  Still  may be working just fine for a texture representing mostly same material.

    To do so you don't need any "generator"  . Just high pass filter and a gradient map in Photoshop or similar things in Substance Designer.    
    Hi pass  over depth image to  make an accent  on crevices.  Gradient map to recolor certain depth values to certain roughness/gloss values.  

     You could save the gradient in Photoshop presets and it could be your quick "generator" 

    ps. Work in 16 bit colors . Depth manipulations go not very well with 8 bit.  Set Photoshop to "sGray" for  grayscale  values   if you going to save roughness as a channel inside RGBA texture
  • JordanN
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    JordanN greentooth
    Apologies for hijacking the thread but it's a relevant question.

    Is there a difference between a gradient and a non-gradient roughness map? Since a gradient implies a gradual transition or fade, how does that translate into PBR science? 

  • gnoop
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    gnoop polycounter lvl 7
    JordanN said:
    Apologies for hijacking the thread but it's a relevant question.

    Is there a difference between a gradient and a non-gradient roughness map? Since a gradient implies a gradual transition or fade, how does that translate into PBR science? 

    not sure if you asked me but with "gradient" I meant only gradient map adjustment in Photoshop. A tool to remap certain pixels of height image to whatever color or gray values you want.    No science.     just a way for doing things quickly  using Photoshop presets.   
  • Brian "Panda" Choi
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    Brian "Panda" Choi sublime tool
    @Optimus

    Dyou try using the search bar?



    Regarding applying the method for generating gloss maps as you do for normal maps, I would encourage you to remove yourself from such a process soon.  I think we used to do it back in the early 2000s, but we have alternatives now that make creating accurate gloss maps more quickly and efficiently instead of just pulls from a bitmap image.  There's far too many issues that arise from just a simple generation.
  • RN
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    RN polycounter lvl 4
    @JordanN I think the gradients or soft edges in a PBR map can represent what a surface should look like to the naked eye, rather than what it is logically.
    For the metallic parameter for example, a material can't be both metallic and non-metallic, but the only way to make a PBR dusty metal material (metal covered with a non-metallic dust) would be to use a map that has soft in-between values for that parameter. Despite going against reason, it would look more realistic that way.
  • Thanez
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    Thanez polycounter lvl 3
    Bitmap2material can do what I think you're asking if the image you're working from is suitable and only has one material in it.
    https://www.allegorithmic.com/products/bitmap2material
    If the image has multiple materials in it, it usually doesn't end well.
    Generators such as these are very limiting tho, so it can be a hassle to pull off a specific effect.
    I suggest you wean off generators and start to make your own materials.


  • Andy_3d
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    Andy_3d vertex
    You can use CrazyBump for generating function maps basing on the diffuse and then correct it manually if there is such need. In general you need to observe how the glossiness looks on the original material and use the diffuse map as a base for painting other maps. sometimes it is easy tasks because often glossiness features cover the diffuse features.
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