Traccia della Forma – Trace of the Form is a site-specific video mapping project that activates the façade of Piazza Castello as a space for visual experimentation. Geometries, lines, and chromatic fields redesign historical architecture, generating a perceptual stratification that connects form, light, and memory. The intervention builds a dialogue between digital languages and urban heritage, transforming the architectural surface into a dynamic field of transformation, suspended between permanence and mutation, past and contemporaneity.