Approaches for generating virtual representations of smart objects in a 3D visual programming interface. The interface displays a 3D virtual environment containing virtual objects that represents a real-world environment containing smart objects. The 3D virtual environment displays virtual objects in a manner that is spatially accurate relative to the physical objects in the real-world environment. For each virtual object representing a physical object, a logic node (port node) is displayed, the port node representing the set of functions associated with the physical object. The interface enables users to create, delete, or modify different types of logic nodes (representing functions) and create, delete, or modify links (representing data connections) between logic nodes within the 3D virtual environment. The authoring of the logic nodes and links produces an executable program. Upon executing the program, data flows between the logic nodes are visually represented as particles moving between the logic nodes.