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>There are people who use bump maps instead of displacement maps
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>>576419
care to tell the difference?
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>>576422

shadow trick vs real geometry displacement.

displacement maps are always better, in every situation (bar possibly small grain detail) but the render times get hench.
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And what's up with that if you only need small height detail and you, understandably, fucking hate dealing with displacement? Just sacrificing render times and reaching straight for displacement to add detail before exploring more efficient, universal methods is bushleague.
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>>576422
Displacement map: large scale detail via geometry extrusion. It physically changes the mesh geometry, so it's good to use when you want the silhouette of the object to look believable with respect to the facing surface. Since you're actually subdividing the mesh at runtime, this is very expensive. Small-scale details need a massive amount of subdivisions, so it's best kept for large geometry changes.

Normal map: medium-scale detail via light shaping. It stores data about the angle at which light strikes the surface, giving the illusion of shape and not just height. The underlying geometry doesn't change, so trying to compact too much surface detail into just a normal map will look bad at oblique angles. It also tends to get "dirty" when loaded with very fine details, so it's best for medium-frequencies.

Bump map: small scale detail via brightness surface shading. Simply makes details stand out by shadowing or highlighting them based on the bump value, obviously this looks like shit at larger scales.

There's no reason you can't use all three map types for any given subject, for instance; displacement to define large masses on a body, normals for details that have shape but don't necessarily drop a silhouette like creases in the skin or scars, and bump for the skin texture itself. Overloading just one map type with detail or compensating with excessive resolution generally isn't a good idea.
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>>576423
I don't think you understand the question. Whats the difference between a greyscale 32bit float bumpmap and a greyscale 32bit displacement map ?
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>>576419
Bump maps are good if you don't want to fuck up silhouettes. Not realistic but more of a stylistic choice.
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>>576425
Achievement unlocked - actually contribute a knowledgeable useful post to /3/
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>>576419
Potential quick and dirty method for exploiting displacement map in max without relying on displacement at render time, particularly useful if you have a supplemental bump map you can use at the end.

1. Make duplicate of basemesh. Supply this mesh with a very high number of subdivisions.
2. Apply 'Displace' modifier. Not 'displace mesh' or anything else, just 'Displace'. Plug in displace map
And get it looking how you want
3. Collapse down to poly, export as hi-poly obj.

Repeat process with original mesh, but use far fewer subdivisions at the start, and you should have a reasonably low/mid poly mesh to bake the HP version onto. You should probably use a cage at bake time.

Combine the normal map you made from your HP version with a bump map (or even the original disp map in a pinch) and boom - youve substituted your high-cost displace element with a low cost mid-poly base mesh

Displacement sucks. Avoid it at all costs.
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>>576428
He just told you...
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>>576449

I think >>576428 was asking not what the difference between the map types is, but why using a hi res displace map in the bump slot is not a legitimate practice (in a slightly cunty way).

And it is, I guess, if all you want is a little bit of surface detail and you've got a displacement map just burning a hole in your pocket. 32 bit is probably overkill, but yeah it'll probably do the trick with some adjustments.

OPs post kind of annoys me desu because it's another one of these 'you're doing it wrong!' type whinge threads, like we're all actually playing a game here and not everyone is sticking by the rules or something.

OP - if someone puts a displace map in the bump slot and gets the result he wants, that's the end of it. Get over it.
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>>576449
He told me the techniques which is about the shaders, not about the actual 2D maps.
Displacement maps and bumpmaps are the same thing and you're all getting trolled.
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>>576456

Then the phrasing of the ruse is bad.

>l'll use a Displacement map on this
>I'll use a Bump map on this

no one would reply saying "actushualy they are the same thing"
>>
>>576425
>Overloading just one map type with detail or compensating with excessive resolution generally isn't a good idea.
I'm guilty of this, and it always looks like shit. Thanks for the post, makes a lot of sense.
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>>576458
words do have meanings
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>>576463

yes but the implication is important
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>>576464
implication comes from the word. both displacement map and bumpmap are 2D greyscale images, they are related to, but don't mean displacing geometry or modifying normals.
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>>576437
>Displacement sucks. Avoid it at all costs.
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Protip: Use a combination of both
>A displacement on broad details that affect the silhouette of a character, like folds or muscle definition
>A bump for fine and grainy details, like skin pores and small wrinkles

This allows for the maximum amount of detail and quality in a reasonable polycount
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>>576419
there are people who don't mind their own fucking business and pretend this is /v/
none of them are older than twelve




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