Visual Languages (VLs) play an important role in software system development. Especially when looking at well-defined domains, a broad variety of domain specific visual languages are used for the development of new applications. These languages are typically developed specifically for a certain domain in a way that domain concepts occur as primitives in the language alphabet. Visual modeling environments are needed to support rapid development of domain-specific solutions. In this contribution we present a general approach for defining visual languages and for generating language-specific tool environments. The visual language definition is again given in a visual manner and precise enough to completely generate the visual environment. The underlying technology is Eclipse with its plug-in capabilities on the one hand, and formal graph transformation techniques on the other hand. More precisely, we present an Eclipse plug-in generating Java code for visual modeling plug-ins whic...