Studying the regeneration and revitalisation of urban tissues involves addressing transitional changes as processes occurring over time. Traditional methods in the Italian morphological theory aim to develop a qualitative and conjectural approach to uncover transitional laws within the city. In these methods, maps play a fundamental role in studying the process providing a first interpretation of what changes and what remains fixed inside the city. However, a gap exists between traditional studies and emerging quantitative methodologies. This research investigates maps developing their diagrammatic components to bridge traditional approaches with new perspectives in the field. The starting point is the analysis of maps of the cities of Venice (Saverio Muratori), Como (Gianfranco Caniggia), and Turin (Augusto Cavallari-Murat). By decomposing these three maps, it becomes possible to define the temporal, symbolic and diagrammatic components that make these maps a tool for studying urban change with a forward-looking perspective. The research enhances map components that can help visualise the qualitative method, working on diagrammatic elements of the tool. This approach is a starting point for developing a methodology and a tool to read morphological transitional events. The final output is a diagram that bridges the gap between traditional methods and innovative AI tools.