Interacting with Virtual Plants: a Client-Server Approach

In Functional–Structural Plant Modeling, a main objective is to understand the interaction between plant morphology and the environment. This requires the development of tools that allow users to validate mathematical models on the basis of their graphical output: the Virtual Plant (VP).

In this study, a client–server approach was used to separate the VP simulation engine from VP rendering and facilitate its use over the Internet. The system’s components can be developed independently by specialists with different areas of expertise—such as engine developers, parameter estimators, and testers—and can use different computing resources.

The client and server applications communicate using the SOAP protocol to exchange XML documents. An XML dialect called the Virtual Plant Modeling Language (VPML) was devised to encode a plant grown within a given environment (climate) over a specified time interval. VPML can encode anything from a single plantlet to a complete plant history consisting of several snapshots taken during the growing period. VPML maps only the plant’s structure—that is, how plant modules (internodes, buds, petioles, and blades) are connected—together with the values of their graphical and physiological parameters.

The graphical features of the plant modules are obtained from separate VRML files and used by the client to construct the VP’s graphical appearance. The client also allows users to interact with the virtual plant by taking advantage of Java3D’s native features: users can select, query, and prune individual modules, and then submit the modified plant to the server to simulate its growth until another date.