© Disney/ Pixar

In partnership with Pixar's Studio, we are delivering a way for the renderer to automatically switch from a bump map to a roughness value depending on the size of a feature in the camera.  This, in turn, will also improve your render times due to the lower sampling rates needed to render such details.

One such example is Louise Nash (shaded by Yeon Kang) from Cars 3.  Here you can see extensive wear of the clear coat on the paint job, which creates micro-scratches and breaks up the specular in interesting ways.

A Bump Roughness map helps keep those micro details in the wide and medium shots as shown in this closeup example below.

This is not only is this an improvement in technology, but this technique allows you to enhance your storytelling with wear and aging. 

Photorealism is all in the details !

There are many other types of materials that benefit from the added detail that Bump Roughness maps bring, such as carbon fibre, metals, plastics and fabrics.

© Disney/ Pixar

PxrBumpRoughness

b2r Texture

This expects the first derivative map, let H be a height field, then each channel are defined as r=dH/du, g=dH/dv, b=dontcare

Texture Type

Map type to be used as your Bump Roughness Map

TxMake Icon

Show settings in Texture Manager

Manifold

Connect a manifold node here to control the position, rotation and tiling of your Bump Roughness map

Multi Manifold

Connect a PxrHexTileManifold or PxrRoundCube Manifold here.

Bump Roughness

Base Roughness

This is the roughness of the base surface when fully zoomed into the detail

Texture Roughness

Set the texture roughness to be provided by the input textures when fully zoomed out from the detail. It is combined with the base roughness. The default of -1.0 lets the texture provide its natural roughness.

Gain

This is a multiplier to the aggregate roughness

Bump Normal Gain

multiplier to the normal map magnitude

Anisotropy Gain

This is a multiplier to the aggregate anisotropy

Advanced

Adjust Amount

Amount to adjust the normals when they are facing away from the camera

Surface Mix

The amount to mix the resulting normals with the surface normals

Blur

Amount of blur to apply to texture lookup.

Filter

Which filter to use. (unfiltered/closest not advisable for displacement.)

Filter Scale

Multiplies the size of the texture filter, less than one for sharper textures.