[Darius]

I have a displacement attached to this material with the following settings:




Does anyone know why i am getting these strange results? Do I have to add lots of faces to the polygon?

[Tim Ellis]

Increase the number of subdivisions on your ploygons for the brick mesh, then increase the smoothing angle to 120' and recalc the normals (if in MXST).

That should help remove the bad displacement areas and should also sort out the bad edge displacement at the top of the window frame.

Check your displacement map matches the colour map and uses the same uv mapping and channel.


Tim.

[Darius]

Thanks Tim

I tried your suggestions. I subdivided the polygons and entered the new displacement values as shown below (I tried 120 for the precision value but there where still gaps):



These are the results i got:



How do i close the edges?

The only thing i can think of that might be causing the problem is that the polygons are divided into triangles and not quads as the model was produced by other CAD software. Would this be causing the problem?

Another thing i have noticed is that the height values are not accurately represented. I have a value of 0.2 cm for the height but the image is showing grooves in the bricks which appear to be about 2 cm deep. In Maya i have the units set to centimetres and the building is scaled to the correct size. Why do the grooves appear deeper than the values i am using?

[KurtS]

Are you sure that the surface is subdivided? Looks like you still have some large triangles.

About the corners: Try to use a different (higher) offset value. try also to smooth the object using a smoothing angle larger than 90 deg.

[Bubbaloo]

Also, you can put a small chamfer on the corners where the displacement is seperating and smooth those faces.

[Tim Ellis]

Yes increase the object's smoothing angle, rather than the smoothing function in the mxm.

That will close the edges for you.


With regard to your height issue, you don't have absolute checked in the mxm, so will be 0.2 units not 0.2cm.

Keep the offset at 0.5 for this case, so the bricks displace out 1cm and the cement displaces in 1cm. (This will only be true for 2cm with absolute checked. Don't forget that the absolute height would be for a displacement map which has a white value of 255,255,255 for the bricks and 0,0,0 for the cement.)

Tim.

[Renato Lemus]

smoothing angle should be >90

[Darius]

Thanks for your suggestions.

Its getting closer, but not quite there.

I have made the following suggested changes to the displacement values:



...and got the following results:



The gap hasn't closed completely. How do i close the gap? Do i need to add more subdivisions to the geometry or do i need to increase the precision value?

I have also tried rendering without using displacement and relying only on a bump map (shown on the red brick only) to give the impression of relief on the surface, but even with the bump values at full the result is flat and not as impressive as using a displacement map.

The bump settings i used are:



The bump map i used is this:



and the result is this:



This looks very flat. I cant see a bump effect. Is there any way to make the bumping more pronounced or is this the best that can be achieved?

[Maximus3D]

Can you show what your geometry looks like ? with the subdivs you added..

I ran similar tests in the past and at first i had equally bad luck like you with visible gaps but i managed to eliminate those gaps completly by having a solid brickwall material with walls subdivided enough and aligned together at the corners. And ofcourse the correct smoothing angle set.

Here below are thumbnail links to my results, click on them to view them fullres.




/ Max

[Fernando Tella]

This will still close the gap:

smoothing angle should be >90

Geometry smoothing angle.

[Darius]

Thanks Fernando. Where can i find the smooth angle setting? Is the smooth angle setting a property of the geometry i.e. in Maya (which is what im using) it is know as soften/harden edge normals. Is this what you mean by smoothing angle? Do i have to select all the corner edges of the building and alter the edge normals?

NB I am not using Maxwell studio. I am using the Maya plug-in. Is the smooth angle setting available in the plug-in?

Maximus3D the geometry is quite messy. It was modelled using other CAD software. This is the model before subdividing it:



This is the model after subdividing it:

[-Adrian]

I think you need a much closer vertical edge right of the building's edge.

[Bubbaloo]

Your walls subdivisions need to be relatively equal with no long poly's/triangles.

[Fernando Tella]

I'm not a Maya user but I guess that could be the option. In max I select all faces, set angle and hit auto smooth; studio has an option too to do so in object properties (set angle and hit recalc). To do that and don't get too bad results you should first add some edges parallel and near the corners so the normals of the most part of the object don't get odd.
In general subdivision should be more regular if you can do it in Maya to get nice results.

[oz42]

I seem to remember someone posting about this issue recently and it turned out the gap was caused by the displacement going all the way from 1 to 0. If the displacement stopped short of 0 it was ok (I think) I'll try to find the post and put a link here.