With high probability, the shop_materialpath attribute on points no longer works.

When creating attributes of type string in python, they are not initialized with default values. Therefore, you must first create an attribute, and then set the value to it:

node = hou.pwd()
geo = node.geometry()

geo.addAttrib(hou.attribType.Global, 'newAttribName', '')
geo.setGlobalAttribValue ('newAttribName', 'newAttribValue')

When using volume procedural (for example, for gridless advection), the resolution of the container becomes equal to 100 voxels along each axis. Therefore, volume quality must be increased:

volume quality =  (size along a larger dimension) / 100

This value is best set on the object.
If the rendering takes too long, you can create a multiplier for volume quality and reduce its value by a couple of times.

In volume procedural, you can use VDB, but you need to do vector split. The results of working with VDB and volume are almost the same.

Also in volume procedural, you can increase octree divisions. This eliminates the need to calculate empty areas. A value of 64 is sufficient; large values will take a long time to prepare before rendering.

The effect of the Z-Importance value on render time and on the image quality of the ocean with displacement:

Decreasing the Roughness parameter decreases the maximum amplitude that anti-aliased noise can generate.

When loading an animated SOP Scalar Field in the dynamics, you need to switch Set Always for:

1. Use SOP Dimensions
2. SOP Path
3. Time

Attributes must be of the same bit depth. If 16-bit float is used to save disk space, then you need to cast them back to 32-bit float after loading the caches. Otherwise, problems may arise. For example, object merge branches with 16- and 32-bit attributes in some cases can break all attributes on the geometry.

The pcfilter function sometimes may not understand the point.distance argument. Perhaps this is due to cases where there are no primitives.
Use the filter by the position of the point cloud.

The name and path attributes are not used by packeds. All necessary information is stored in intrinsic attributes.

Channel ranges are specified in seconds by default in CHOP nodes. If we are used to working with frames, then we must not forget to change Units from Seconds to Frames in the Common tab.