Calculate a bumped normal based on a floating point scalar displacement map. @parameters
scale: An object-space scale applied to the bump.
disable: Use the geometric normal (ignore the modified bump).
inputBump: If 'Input Bump' is connected (and 'Filename' is not specified), the pattern executes the upstream shader graph connected to 'Input Bump' 3 times, once at the shading point and once at P+du and P+dv. Then it crosses the results to get the bump normal. Note that if you have a fixed texture and UV, it is highly recommended to use 'Filename' method below because it is 3 times faster! If 'Filename' is specified below, 'Input Bump' is ignored.
filename: Filename could be a color or monochrome file. The shader reads only one channel of the file from Channel specified below. If 'Filename' is specified, the pattern has no upstream graph connected. Instead it reads the bump value from the texture file. The bump pattern gets the derivatives from the texture AS it filters it, so it doesn’t have to read texture values 3 times. As a result, however, it can only take the derivatives of a single channel, which is specificed by 'First Channel'. The shader currently does not allow modifying the manifold of the texture. If 'Input Bump' is connected and Filename is also specified, Filename is used while the connection of 'Input Bump' is ignored.
firstChannel: First channel offset to be looked up for Filename.
atlasStyle: Specify which atlas style.
invertT: Inverts the t texture coordinate for texture lookup.
blur: Specifies how much to blur the result from the texture.
lerp: Selects whether to interpolate between adjacent resolutions in the multi-resolution texture, resulting in smoother transitions between levels.
manifold: You can connect a PxrBumpManifold2D here. Any other manifold type will be ignored.
inputN: An additional normal to be added to the bump normal.
reverse: Reverse the resulting normal.
adjustAmount: Amount to adjust the normals when they are facing away from the camera.
surfaceNormalMix: The amount to mix the resulting normals with the surface normals.