Any way to create a bas relief?

[kac]

I make various models and often convert them to bas reliefs for belt buckles and keychains etc. I usually export the models out and bring them through 3dCoat where I create a bas relief. This often makes really bloated models and tend to lose some tiny details and require much cleanup and refinement.

 

Is there a way to create a bas relief within FZ? If not it would make an awesome plugin.

 

Thanks,

Ken

[chrisd]

If you can render out a depthmap (greyscale values based on distance from rendering camera) it could be used in the Displacement tool for instant bas-relief.

 

I'm on a much older version of FormZ so perhaps rendering out a depthmap is possible in a newer version. If there is no render to depthmap available, it can still be achieved as follows:

 

- Set rendering camera to ortho/parallel projection (should be set like this for depthmap too if its available as a render option)

- Apply black to white gradient map from the side of the objects, 90deg from rendering camera direction

- Consistent mapping for multiple objects (may need to join or group for this) so the gradient range goes from the closest object to the furthest object from the rendering camera.

- Positive/Negative bas-relief can be created by inverting gradient.

- Use ONLY ambient light for illumination.

 

 

 

 

[setz]

I use 3DCoat all the time with FZ for just this purpose.  It's actually very efficient.  My models in 3dcoat are large, usually between 10-20 million polys.  The key is in Decimating the model PRIOR to exporting from 3DCoat.  My process is as follows:

 

1. If working in voxels, convert to surface mode.

2. I like to change display to wireframe at this point to see what effect the decimation is actually having.

3. Go to the Geometry menu, and choose decimation.  Enter your reduction percent.  I usually use 95-98% which for a 10 million poly model will output a mesh of 200-500k polys, FZ handles these fine.  Verify that the wireframe and the shaded views that your details are preserved.  Undo and repeat until you have a good balance between low count and high detail, .5% can make a difference.

4. File/Export Model

5. When the Export Dialog asks for amount to reduce the file on export enter "0". This is important because for some reason the export decimation is much more destructive to detail.

 

Forgive me if you know this info already, but hopefully it will help.

[kac]

I have used depth maps and displacement maps but they don't give you good detail. What I didn't know was exporting out at 0. That is something I need to check. Voxels are handy but when I make my master models on my SLA printer you can definitely see the difference in quality of the surface between the voxelized object and one that was constructed in full nurbs. What I have done in the past but takes some work is retopo the voxel objects into quads and convert those to nurbs but it depends on the complexity of the relief.

 

My current project is an antique steam fire pump that has spoked wheels and tons of pipes and fittings. If FZ had some sort of cloth sim it might be possible to do it entirely in FZ.

 

Thanks for the tip on the export, I think that's where I have been losing a lot of detail and yes I do use surface mode and the decimate brush.

[chrisd]

I have used depth maps and displacement maps but they don't give you good detail.

 

Ken,   Are you indicating that any application using 16-bit displacement is not sufficient for your use?

[setz]

While the decimate brush is good for local areas, the Decimate Menu option under Geometry tab is a quick way of making the entire model more efficient in one click.

[setz]

I would love to see your Fire pump when it's finished or even WIP would be interesting.  Post it to share your FZ work.

[kac]

I have to head over to the museum to get some pics and sort out the tiny details I can't research on but this is what I have so far. Evenutally I hope to have some cool looking belt buckles done. Not a difficult model by any stretch, just tedius.

[setz]

That's such a cool project! With all the possible details It's quite a project. Are your uderlays from the museum as well? Will the buckles be an angled view or an elevation? Do share your process including the 3DCoat part. Thx.

[kac]

Once I have a couple more reference images I'll finish the model as a complete unit. From that I will export an obj out (supports multiple meshes where stl is single mesh). 

I will then convert that file in 3d coat and create the bas relief in the direction I want. probably a 3/4 front view then export out an stl from 3d coat and bring it into FZ with the rest of the buckles components and text.

 

From that composited model I will print out a master(s) on my sla printer.

 

Not sure if there will be a substantial number of orders or not, working on spec here so I will either use delft clay (similar to sand casting) or bust out a mold for my centrifugal caster.

 

Nice that FZ can import stl files as well as nurbs. This makes jumping between programs easier. Previously I would have to retopo the relief if possible and do a nurbs smooth object OR bring everything through 3dCoat. 3dCoat handles sculpted objects pretty nice but a little shaky on text object and lacks any real precision.