Advanced Game Engine Wizardry for Visual Programming Environments

Visual programming environments empower end-users with interactive input and feedback mechanisms that support live and exploratory programming. For creating these environments, language engineers require enabling technology. Language workbenches and meta-programming languages support rapid construction of interpreter back-ends. Game engines are specifically created for rich interactive user experiences and have the potential to augment this technology even further with maintainable front-ends. However, these technologies presently live in separate technological spaces. We aim to automate the creation of visual programming environments by integrating the two. We propose Raven, a meta-framework for rapidly prototyping visual editors that exposes key 2D features of Godot in a programmable user interface. Using Raven's declarative notation, language engineers can concisely express the structure and styling of tree-based editors. We demonstrate our approach by: 1) integrating Raven into the Rascal language workbench; and 2) creating two editors for the live state machine language.