Displacement maps and Bumpmaps and Wiki,

#1
Hi, another query from a real beginner - this time about making a realistic (within the confines of Cheetah 3D's ability) of a lumpy/bumpy object, eg the pebble box below, from PBRtist, which I made this a.m. with the usual sections upgrade, subdivision and displacement (offset 0.11) mods coated with a PBR shader using the diff. rough. AO and Bump supplied by PBRtist
Wiki however say at: https://en.wikipedia.org/wiki/Displacement_mapping

that "Displacement mapping is an alternative computer graphics technique in contrast to bump mapping, normal mapping, and parallax mapping, using a (procedural-) texture- or height map to cause an effect where the actual geometric position of points over the textured surface are displaced, often along the local surface normal, according to the value the texture function evaluates to at each point on the surface. It gives surfaces a great sense of depth and detail, permitting in particular self-occlusion, self-shadowing and silhouettes; on the other hand, it is the most costly of this class of techniques owing to the large amount of additional geometry. ".

I followed Frank's 'Basic PBR Set UP2.jpg' below, but Wiki seems to say it's wrong to mix a procedural technique with a PBR.

I can understand all the Maths with CG, but the implementation of the various 3D CG Apps leaves me a tad puzzled.
 

Attachments

frank beckmann

Well-known member
#2
I don´t see/used any mix. All is/was image based in the set up. And don´t forget to feed the Displacement-modifer which needs more geometry of course.

Cheers
Frank
 
#3
I don´t see/used any mix. All is/was image based in the set up. And don´t forget to feed the Displacement-modifer which needs more geometry of course.

Cheers
Frank
Hi Frank,

If the Basis PBR Set Up didn’t come from you, then my apologies. Who ever it was possibly used the Mix Node to utilise the AO, coz, the PBR node at that time didn’t have a AO input.

My PBR set up is below and I did use Disp Mod separately, hence my remark about mixing the PBR shader with the Disp Mod, which I assume is a procedure control. I increased the sections of the cube to around 50 all round and also Subdiv’d. I used the wonderful ‘sculpture-exhibition. Hdr’ for lighting.

As an aside, I download a lot of freebie textures, materials, Hdr’s etc and have noticed that some ‘height’ maps need to be inverted, ie inputed to the lower input of a subtract node; I am learning all the time - although I never will, nor intend to make money out of Cheetah or CG, I find it fascinating and keeps the grey cells busy and the grim reaper away :)
 

Attachments

Last edited:

frank beckmann

Well-known member
#4
Hi Frank,

If the Basis PBR Set Up didn’t come from you, then my apologies. Who ever it was possibly used the Mix Node to utilise the AO, coz, the PBR node at that time didn’t have a AO input.
Martin implemented the AO channel after I made my quick hint on PBR set up.

Cheers
Frank
 
Top