In this article, we show a flow-based programming environment for interactive geometry software. Flow-based programming is one of the programming paradigms. All of the processes and data are represented as nodes, and we connect processes and data with edges. We call the figure with nodes and edges graph because the figure looks like a planar graph. There is a lot of software implementing flow-based programming. However, there are few mathematical software based on a flow-based programming environment. So, we develop experimental interactive geometry software to generate kaleidoscope patterns based on flow-based programming. The software shows us some advantages of flow-based programming. First, it is easy to understand the procedure of construction. Second, flow-based programming is flexible. Third, flow-based programming has high extensibility. We seek possibilities of practical use of the geometrical construction software with flow-based programming.