correct terminology: shader maps? render maps? what are they called?
polycounter lvl 5
Hello Polycount!
I am a painter and illustrator, getting into 3D.
There are some concepts in 3D that are very helpful in 2D painting. One of them is the concept of "maps" like normal map, emissive map, specular map, diffuse map, etc.
What is the name of the category of these maps? There must be a more precise word than just "maps". Is it "Shader Maps"? Or "Render Maps"? Or something else? Or am I throwing different categories together here? As in normal maps being different from specular maps and those being different from texture maps again?
*confused*
hope you can help
Best,
Dorian
PS. just to not make this a text-only post, here's an image I did with ZBrush a while back:
I am a painter and illustrator, getting into 3D.
There are some concepts in 3D that are very helpful in 2D painting. One of them is the concept of "maps" like normal map, emissive map, specular map, diffuse map, etc.
What is the name of the category of these maps? There must be a more precise word than just "maps". Is it "Shader Maps"? Or "Render Maps"? Or something else? Or am I throwing different categories together here? As in normal maps being different from specular maps and those being different from texture maps again?
*confused*
hope you can help
Best,
Dorian
PS. just to not make this a text-only post, here's an image I did with ZBrush a while back:
Replies
-Color = Diffuse Map
-Shiny = Specularity Map
-Tightness of Shiny = Glossiness Map
-Glow = Emissive Map (or self illumination map)
-Transparency = Opacity Map (or opacity mask)
-Face information on a polygon = Normal Map (grey scale = bump map)
-Displacement = Height Map
Isn't a normal map just overwriting the meshes' normals (the direction they'd be facing, not the depth)
Gah, you're right, sorry.
Not necessarily. That's only true for an Object-space normalmap. A Tangent space map (which is used much more and seen as the standard), doesn't overwrite but rather bends the normals relative to the already existing mesh normals.
beyond the game industry (and even in it) the naming conventions are really haywire. nothing is really standard and unambiguous. you could easily call a gloss map a specular map and vice versa and it'd still be completely valid to a lot of people.
the wiki does an ok job at trying to categorize them.
Gloss maps, sometimes, are called Specularity Power, which kinda makes sense, but a CGI artist will always have a basic training in Gloss, as the first term.
Which raises an interesting question from what you said, why doesn't the industry homogonize the lingo in mapping?
why don't we homogonize normal maps and xyz cord directions and scale?
standardizing would be nice, but it's pretty illogical how we use it. why is a glossy reflection the opposite of a high gloss reflection? i wish people would just call them roughness maps, would be both less ambiguous, more intuitive and has a tangible meaning.
What I was getting at was that they were for the normals, not depth. 'Considering' probably would have been a better choice of words on my behalf.
.
The exponentiation of the cosine term in the phong and blinn models *is* a quick and dirty way of simulating surface roughness and more diffused scattering.
I was thinking of the cook-torrence and oren-nayar models, which use roughness in a different way than a simple exponent, though the spirit of the different approaches is the same.
shader is a material... a shader is a bit of code that takes image maps uses them to create the properties of a real life material...
properties of a shader would be
color - diffuse
spec -
gloss-
glow, emissive, self illumination
refection-
opacity, transperency
refraction
bump
displacement
It's all entirely subjective though, because it's easy to apply different meanings down to the fact the implementation itself isn't standardised. Things like normal maps are pretty standardised, which is why everyone usually knows what you're tlaing about (although there are still discrepencies between coordinate systems, which is another example of implementation differing).
Value = 1 is Self Illuminated while higher then 1 determines the Glow around the Self Illumination.
I personally would love Normals and Bi/Tangents be harmonized before anything.
Emissive maps are generally not handled as if they were a source of lighting and don't interact with the diffuse or specular in the same way, which is why they can be treated as a 'glow'. Lots of people use emissive maps to kind of do what I'm describing above though, especially in conjunction with a glowing source.
The trouble is that not everyone implements things this way
Different material properties having different names in different engines makes sense though since the complexity of "recreating nature" makes for many ways of going about it..
Looks like we have:
Texture Maps - this seems confusing to me since there are "texture maps" used as parts of materials as well, correct?
Also, if "Texture Map" is the overall category, would you guys think of a "normal map" as being a "texture map"? To me it seems they are at the same level of hierarchy. That said... all these maps are textures, right? What a mess hehe
Shader Maps - I prefer this one I think. Any arguments against using that? A shader is code describing material properties, correct? Is it correct to say "shaders contain "maps"?"
Material Maps - never heard that one but it seems it would work as well. Is it practical to use "shader" and "material" as synonyms?
Render Maps - the maps are not as much about the rendering as about controlling material properties so this one can probably be neglected.
How about Material Property Maps? That is exactly what they are, right? Anything wrong with this term other than it being a bit clunky?
Anything to add?
Or subtract?
Thanks!
And welcome!
Definitely not looking for what sounds best
Cheers!
edit: and nice & fun work on your site! Really looking forward to exploring all the talent here!