Why is Arnold 5 rendering soft edges hard?

[batouyukinawa]

smooth-ishard.jpg Does anyone know why Arnold is rendering soft edges hard? I don't want to use a blinn either, I need to use a PBR shader.

[kyanetemadi]

Press "3" for a smooth mesh preview before rendering, or smooth it in Maya with Mesh -> Smooth.

But another very good way is to set the subdivision in the shape node of your objects you want to smooth. So you have everything lowpoly in the viewport and smoothed when its rendering in Arnold.

Go to the Arnold attributes in the shape node, down to Subdivision, and set the type to catclark and set your iterations (e.g. 2). When you hit render now, the lowres should be smooth in the final render.

[batouyukinawa]

Thanks but I'm trying to render a low poly model, there are no supporting edges to work with. Smooth preview would deform the asset. I need Arnold to render out edges as they are. IE: Hard edges are hard & and soft edges are soft. Right now, it's not doing this. It's rendering soft edges hard which is causing issues with my maps. However if I render the standard surface shader without maps I get the same thing. It hardens my softened edge.

[kyanetemadi]

Aahh, I see.. I'm not much of a low poly guy, so I don't have much experience with that 🙂 I don't know if what you are trying is possible. You have a low res model and want to make it look smoothed like a high res model?

[Reithierion]

I have the same problem and increasing the polycount by smoothing does not work and is not a good solution either way as there may be a limit on the polygons, say for example, a student doing a student project. I have had to go back to a previous saved scene and start again with exact same rig and material minus hard edges on specular/roughness. It's definitely not normal map issue as I broke connection and tested each individually. There is no answer online for this. It's most likely another bug.

[nwoolridge]

It looks to me like Arnold is accurately rendering a low poly model. Using Arnold render time subdivision is not an issue, and is a standard part of the workflow (poly limitations or not).

You may also be looking for the Round Corners shader, which adds a "virtual" bevel/chamfer on sharp corners. It is described here: https://docs.arnoldrenderer.com/display/A5AFMUG/Round+Corners