Hi everyone.

Anyone know what the "normal maps" for the Medusa and Lamia over at Sixus1 are for?

They only cost a buck, but I don't know if I need those or what.

Thanks.

D.

I think the Poser 7 Pro supports normals.  maybe, it's related to that?

I could use a Medusa.  are the snakelets posable?

They are indeed a PoserPro feature.
I believe they are like bump maps on steroids. They give a better effect than regular bump maps, but don't change the surface shape like a displacement map.

Quote - They are indeed a PoserPro feature.
I believe they are like bump maps on steroids. They give a better effect than regular bump maps, but don't change the surface shape like a displacement map.

Hi raven!

Do you have an example you could point me to showing a comparison of results with a normal map, versus an equivalent bump map? I've seen several people make the claim that normal maps are somehow more capable, but everytime I ask for a demo, I never hear a response. I don't mean "no I haven't", I mean they just don't answer.

Did you experience a situation where a normal map was better, or are you just repeating what you've heard? If the latter, repeat this:

Normal maps in Poser do not influence specular effects, rendering them nearly useless.

Normal maps in Poser cannot be scaled to create more or less of an effect, whereas bump maps can be scaled.

(EDIT) Correction: I justed tested the latest version of Poser Pro - the normal map now affects specular.

normal maps are almost always used from Zbrush or from mudbox.

they make skin details or something similar and then they export it out.

Quote - > Quote -

(EDIT) Correction: I justed tested the latest version of Poser Pro - the normal map now affects specular.

but they dont work with the alternate diffuse and specular. right.

I know that they're faster to render. We don't notice a speed difference in Poser because Poser is spending way more time on other aspects of the rendering, but for real-time games they're really useful. It's just a representational difference. With a bump map, the deviations of the surface normal have to be calculated or inferred from the virtual offset positions of the bump map, whereas on a normal map they can be read out directly. But other than the speed difference, I can't find any justification for the idea that they're better at producing the desired effect. As far as I can tell, they represent the same information and are used the same way - to alter the calculated surface normal of otherwise flat geometry.

Quote - > Quote -

(EDIT) Correction: I justed tested the latest version of Poser Pro - the normal map now affects specular.

but they dont work with the alternate diffuse and specular. right.

Oh yeah, that was it. I just verified it. You're correct, it does not affect the Blinn node or any other specular node - it only works with the built-in specular. Since the Blinn node or Glossy node or Anisotropic node are necessary for realism, I never use the built-in specular, which means normal maps are useless after all. Just use a bump map.

Ok so I don't really need to purchase the normal maps to use the figure in P6. Cool thanks for answering that question for me everyone. Now I can go and finish buying medusa and lamia and that kraken.

And boy oh boy I can't wait to play with them.

I've been wanting a medusa for years now. :lol:

Attached Link: http://developer.nvidia.com/object/photoshop_dds_plugins.html

Hi bb. I've had very little contact with normal maps compared to bump maps, so I'm basing what I believed a normal map to be on things I've read, in places such as Pixologic's ZBrush forum for example. The bump map on steroids reference was in regard to various readings that say that a normal map gives a more 3d bump effect than a regular bump map due to the fact that a bump map only affects the normal in 2 dimensions whereas a normal map can affect a normal in 3, thus giving a better effect. I had a look for normal Vs bump on Google and found the Nvidia Normal Map plugin and decided to have a play.

Also, regarding you saying the strength of the normal map effect can't be changed. I made a normal map from a bump map using the Nvidia normal map Photoshop plugin and applied it to a cylinder prop in PoserPro using the Normal Tangent option on the Gradient Map socket, and that allowed me to utilise the Gradient Bump value to increase/decrease the effect as I wished.

Hmmm.

So that plugin filter calculates a normal map from a bump map.

"The NVIDIA Normal Map filter creates normal maps from grayscale height maps"

So, in other words, it calculates the distortion of the normals based on the calculated slopes derived from a height map. This means that it can only simulate what a bump map simulates. It is another representation of the same information. Furthermore, unless someone can prove me wrong, the functionality provided by the built-in Poser support for bump maps is IDENTICAL to using that filter to create a normal map. Internally, the end result of using a bump map is a normal map. Does anybody know otherwise?

And when you use that scale thing, I agree it has an effect on the map distortion intensity, but it does so in a way that produces de-normalized vectors, resulting in a translation of the surface to something that is not exactly a linear scaling of the height map. Whereas, linearly scaling the bump map precisely translates into a new normal map that cannot be derived simply by scaling the original normal map.

Consider the parameters that go into that filter - in particular the parameter called Scale.

Try making two normal maps, one in which the scale is 3 times the other.

Load them both onto two identical props in Poser. Adjust the Gradient value on the higher (3x) scaled one to be .3333 and use a Gradient value of 1.0 on the other one. Do they look the same? I suspect they won't.

I'd do it myself, but I don't have Photoshop with me. I'm on the road.

 I think the NVIDIA process is a special case.

In contrast, normal maps exported from zBrush have 3 dimensions where RGB corresponds to vectors in XYZ space. NVIDIA's "extrapolation", it would appear, would not give you the same detail as one would normally find. I cannot comment on Poser's implementation of normal maps but in my renderer a normal map and displacement mapping are equally fast to render which is dis-advantageous for normal maps since their silouettes aren't  perturbed.  

I don't understand what you meant here:

"normal maps exported from zBrush have 3 dimensions where RGB corresponds to vectors in XYZ space"

All normal maps are 3-dimension RGB values,, not just those produced by zBrush. There are no other kinds. All normal maps have 3 XYZ values encoded as RGB values that represent a new normal to use. For ordinary normal maps, these are the actual normal to use instead of the surface normal on the object. Only games with static (not rotating) items use such maps. For moveable 3D objects, you want  tangent space normal maps. These are encoded not with absolute 3D space basis vectors (world X, Y, Z axes), but with respect to the the 3D space formed by the surface normal, tangent, and binormal orthogonal vectors of the surface. A tangent space matrix is built and then used to rotate the normal map vector into the actual 3d scene vector. The result is the effective normal of the surface. It's a pretty simple lookup and matrix mutliply, which is why it is fast.

But it's not DIFFERENT. These normal vectors are derived from the displaced surface. 

I'm no 3D math guru, but AFAIK, with a zbrush (or mudbox, or 3dcoat) workflow, you use normal maps for "trick" geometry perturbation (as in percieved but not real), and you use displacement maps to physically perturb the geometry. No bump maps.
Or in other words, you could also work with two greyscale maps, one for the bump, and another for the displacement, but they would be different maps. So in this case, normal maps are probably used so you don't get confused as to which is which.
Just my 2 cents.

Quote - Ok so I don't really need to purchase the normal maps to use the figure in P6. Cool thanks for answering that question for me everyone. Now I can go and finish buying medusa and lamia and that kraken.

And boy oh boy I can't wait to play with them.

I've been wanting a medusa for years now. :lol:

Thanks for turning me on to the Medusa figure last friday.  It was on sale for $10 bucks.  I even love her dress.

Cheers!