Displacement problems

[Bosseye]

I seem to be having nothing but problems lately, and all on stuff I used to have no issue with! Grrrr.

Ok, so I'm trying to add a small displacement to a texture. Normally I would simply add the texture, tick the displacement checkbox in SKIndigo, set the map to texture, load the bump map of my choice to use, set a displacement value and render, job done.

But for some reason, when I follow the above, displacement is simply moving the texture up rather than displacing it in line with the chosen bump mapped texture.

I've never had any issues with this before, what the funk am I doing wrong now?

Thanks,

DisplacementR.jpg[/attachment [attachment=0]DisplacementR1.jpg

[vasco]

Have you done any subdivision settings?

[bubs]

Hey Bosseye, I'd the exact same problem. With me it was that subdivision was set to zero. This used to be within the material editor dialogue box within Skindigo, but is now controlled on a mesh by mesh basis, using the 'edit active mesh' dialogue box. (right click on a face and scroll down to Skindigo items).

Whaat covers this pretty well in his YouTube tutorial on displacement.

Hope this helps, it was wrecking my heads for days!

Bubs

[CTZn]

This is also what would happen when the Offset value alone was to be changed. It is indeed to modify the overall elevation of the displacement wich is defined with the Gain. edit: just checked your settings, vasco and bubs probably came closer to your concern.

If not for albedo and coloured effects (like the absorbtion layer of the glossy and specular), the texture gamma should be 1.0 (for bump, disp, transparency, exponent etc). A different value would "stretch" the data; still, this is an option.

[Pibuz]

..I'd go with bubs tip: check your subdivision parameter for the mesh you want to displace!

[Bosseye]

Hey Bosseye, I'd the exact same problem. With me it was that subdivision was set to zero. This used to be within the material editor dialogue box within Skindigo, but is now controlled on a mesh by mesh basis, using the 'edit active mesh' dialogue box. (right click on a face and scroll down to Skindigo items).

Whaat covers this pretty well in his YouTube tutorial on displacement.

Hope this helps, it was wrecking my heads for days!

Bubs

Winner thanks. Yeah, when I change subdivisions to 10 then it suddenly renders more like I was expecting.

I'm afraid I can't check Youtube from work (most of my rendering is on my work PC - I'll watch the video later at home) so can someone give me some brief indication as to what the subdivision is actually doing - theres no visual change on the face in Sketchup. Whats changed from previous SKIndigo versions, was subdivision of the face not required before, or was it just inherent? If so, why the change, does being able to manually adjust the subdivisions give more power over the behaviour of a texture?

Anyway, thanks all for your input.

[Pibuz]

The manual adjustment gives you the way to control the amount of RAM used. The higher the value, the higher the memory drainage. Sometimes you can stick to non-excessive values, so you can save some GB. But in my experience this is rare.

[cotty]

Winner thanks. Yeah, when I change subdivisions to 10 then it suddenly renders more like I was expecting.

10 is a high value for subdivision and not needed in most cases (and would freeze my laptop )
Here is a little example of the influence of this parameter: http://www.indigorenderer.com/forum/vie ... 21#p114121

(The used 'random triangle colors' are described by Whaat some posts earlier there)

[Bosseye]

That's interesting, thanks Cotty. I can see that 10 is a huge value now, especially on more complex geometry! Not quite so bad on my flat plane perhaps.

[CTZn]

One subdivision level higher will double the polycount.

I estimate my needs based on a small face of the object: I split it's width in two mentally and count one level. Adding another level would mean to create a face as small as the half of this half etc.

Learning to harness view-dependent subdivisions is a must for detailed objects. I see that it is on by default in SkIndigo.