This diagram displays a monitored floor plan with several nodes (representing kittens) to view in real-time. Every two seconds the Part.location of the kittens is updated. The location has a linear AnimationTrigger so that the motion appears smooth.
The Tooltip for each kitten shows its name and photo.
When you zoom in or out the effective size of each Node is kept constant by changing its GraphObject.scale.
See monitoring samples for more samples like this.
A tooltip is an Adornment that is shown when the mouse hovers over an object that has its GraphObject.toolTip set. The tooltip part is bound to the same data as the part itself.
It is typical to implement a tooltip as a "ToolTip" Panel holding a TextBlock or a Panel of TextBlocks and other objects. Each "ToolTip" is just an "Auto" Panel Adornment that is shadowed, and where the border is a rectangular Shape with a light gray fill. However you can implement the tooltip as any arbitrarily complicated Adornment.
More information can be found in the GoJS Intro.