rst option is the type of Point Grasshopper will display in the Rhino Viewport.
Dot
Point
Cross
Dot is a small dot of single colour.
Point is a slightly larger dot with a white center.
Cross an X-shaped cross. (Default)
Preview Plane Size
The option to change the size of the Plane appears as a fly out menu where an input box allows you to enter a value in Rhino Document Units to set the size of the Plane. (You must press Enter to accept the change)
Preview Mesh Edges
The option to hide/show mesh edges catches a few users out, thinking that the Meshing of the Object has failed.
And without...
There is a handy Shortcut of Ctrl+M to toggle between the two options.
Gumballs
As of version 0.9.0064, Grasshopper allows the user to move individual points that are Persistent[3a] by means of a Gumball in the Rhino Document. Volatile[3b] points can be made persistent by way of the Internalising feature found on the Context Menu of Components and Parameters
[3] Glossary:
Volatile - "liable to change rapidly and unpredictably". Referenced objects in Rhino are considered volatile.
Persistent - "continuing to exist or endure over a prolonged period". Internalised objects are considered persistent.
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