Tarsier

This library's primary purpose is to add the point cloud functionality already apparent in Rhinoceros 5 to Grasshopper, with the ambition of treating point clouds as another useful data type, rather than an exotic type.

It is available on food4rhino and the source code is available on bitbucket. It is free for use under the GPL license. Contributions and suggestions are welcome.

It's secondary purpose is to provide tools for creation and streaming of point clouds with common scanning techniques (Kinect V1, V2 and OpenNI2). This is made possible due to the speed increases afforded by the use of the point cloud class. For example, a full point cloud from a Kinect V2 is released in approximately 10-20ms on standard machines, which is more than enough for most purposes. A multi-threaded KD-Tree is also implemented to allow very fast spatial searching.

Alternatives

• Firefly offers an extensive suite of tools dealing with vision and image processing, including Kinect streaming. However, in some cases interpreting the stream as a point cloud is more useful (and often faster!).
• Volvox offers an extensive suite of tools dealing with Point Clouds, and if conventional use is your ambition it is very fully featured and highly recommended. 

There are some notes about interoprability on the Wiki: https://bitbucket.org/camnewnham/tarsier/wiki/Interoperability

If you have suggestions about how the overlap and interoperability may be improved between these plugins please post below.