height map displacement

[dalaylama]

hi,

 

Am trying to make a steel roof,so i think the best way do do it is with an height displacement map. But the result came out sketchy and i dont know why. see picture below

 

Here'S how i made my texture

1.Choosed a mental ray shader

2.Added DSG materiel for color and diffuse map(not sure about this one btw)

3.Added a height displacement map (minimum height 0 max 50mm)

4.Added a tile map to it that i customized to be only vertical stripe

5.Adjusted my render setup in displacement setup at max 60mm

 

then i rendered and it gave me the result as seen below and theses warns

+RC 0.3 warn 082011: difference of min and max samples 4 > 3 may be inefficient

+RC 0.3 warn 082034: sample filter other than box 1.0 1.0 not supported for these sampling levels

+RC 0.3 warn 082035: sample filter switched to box 1.0 1.0

+RCFG 0.5 warn 542002: angle between normal and geometry normal > 90 degrees

 

So what did i made wrong

could it be the low quality of my render setups?

 

Thank you

 

Joel:)

[Peter M. Gruhn]

Two things I think involved here.

 

1) Displacement settings on the render dialog. Way down low on the renderer tab (under MR) are settings for edge length and subdivision. You can also chuck in more polys to the base mesh, even put them in the right place so that the initial subdivisions are smaller only where they are needed.

 

2) Doing it wrong in the first place. It looks like you are doing a "standing seam" roof. Throw some polygons at the problem. There will be far fewer of them, if larger, in the end, they will be crisp and perfect, there's won't be so many of them that your viewport gets bogged down. See the following, they were done with real geometry.

 

http://www.hwb.com/gruhn/3d/bcc/p2f/p2f-South.jpg

http://www.hwb.com/gruhn/3d/bcc/bldg2-out-test02.jpg

[dalaylama]

Thank you for your anwser peter,

 

Excuse my ignorance in 3ds modeling, but how do i add poly to my geometry. edit mesh+Tesselate?

 

Thx

 

Joel

[Justin Hunt]

For displacement with the and A&D shader, scroll down to the mentalray connection, unlock the displacement and add the height map there.

 

 

That warning is saying your AA settings are too low, Try min 1 max 16

 

jhv

[Stephen Thomas]

Thank you for your anwser peter,

 

Excuse my ignorance in 3ds modeling, but how do i add poly to my geometry. edit mesh+Tesselate?

 

Thx

 

Joel

A simple way would be to divide up your roof plane by adding an edit poly modifier then using the connect command. Now select the edges, do a chamfer on them to make them double lines then extrude the thin faces between them.

 

Alternatively if you want something more accurate you could download a cad detail from a manufacturer like http://www.kalzip.com/kalzip/uk/technical/technical.html for example. Then just extrude the profile along the line of your roof.

 

Edit: Though the link above is obviously for aluminium standing seam rather than lead as I think you're going for here. An even easier way would be to array splines along your roof surface then just make them renderable or use a sweep modifier, that would allow you to do different seam details quite easily.

Edited January 25, 2010 by stef.thomas

[Peter M. Gruhn]

Pretty sure that what I did was array splines and check them renderable and switch to rectangular. Made trimming and adjusting ends easy.

 

I agree with using the connect tool; one of my favourites. Tesselate is too often not what I need. If it is not too late, you can also create your initial geometry with the right spacing.

 

If you have already cut up the geometry to go around the windows, you may find the connect tool giving you unhappy results as you connect between a short edge and a long one. I've only got max 9 here, but am pretty sure I was using an Edge Divide tool in 2010 the other day. You could use that to chop up the long edge. Look to snaps and the magnet tool to tweak your verts even, or the [x][y][z] buttons. I really should learn what those are called.

 

And then chamfering the edges is great.

 

You will be close, so giving the stands some thickness is good. If you were further away, you could refrain from extruding them: keep the new this faces, delete the big faces, select only the left edges of each thin strip (all of them) then move it into standing position and use a 2 sided material.

 

Still, I think I like the splines best ;-)

[dalaylama]

Thank you all,

 

Gonna try a couple of them and see what's better, but i think the renderable spline a good idea

 

Joël