Leonardo da Vinci’s Spatial Grammar – outline

**Leonardo’s Spatial Grammar: A CAD Reverse-Engineering Analysis Corpus** 
*(Leonardo’s CAD, Leonardo’s Rulers, Leonardo’s Score)*

**Author:** Giancarlo De Leo 
**Published:** 21 August 2026 (Version v3) 
**DOI:** [10.5281/zenodo.22045814](https://doi.org/10.5281/zenodo.22045814) 
**Zenodo record:** [https://zenodo.org/records/22045814](https://zenodo.org/records/22045814) 
**Views / Downloads (at time of check):** 63 / 13 
**Access:** Open 

### Core thesis
The work challenges the idea that Leonardo da Vinci systematically applied Alberti’s square-grid (checkerboard) perspective. Instead, it argues that Leonardo developed an evolving **metric-modular spatial grammar** grounded in measurable, falsifiable geometric evidence drawn directly from the paintings themselves.

Using **CAD reverse-engineering** and what the author calls the “Aristotelian obvious” (relying only on what is visible, measurable, and geometrically controllable), the study reconstructs the depicted spaces of three key works as architecturally coherent, human-scaled environments rather than purely symbolic or esoteric constructions.

### Works analysed
1. **Annunciation** — Prototype of “inserted geometry”: the niche is treated as a calibrated rectangular spatial box based on a module *q* (half a Florentine *braccio*), with the Virgin’s body sharing the same metric system.
2. **Adoration of the Magi** — Emergence of a generative 4:3 rectangular grid linked to the Florentine *braccio*; this replaces the traditional square grid and better explains the arcades, stairs, and integration of golden triangles / pentagonal geometries.
3. **Last Supper (*Ultima Cena*)** — Culmination in a stereometric “polyphonic” architecture governed by a single module that coordinates width, height, and depth (rhythms such as 1:4:1 and 2:1:2).

### Method
– Direct observation of painted architectural elements (tiles, coffers, arches, steps, etc.) as embedded measuring tools (“inserted rulers”).
– Inverse geometry + CAD reconstruction.
– Anthropometric, zoomorphic, and architectural consistency checks.
– Rejection of non-falsifiable esoteric or forced symbolic readings.

### Available file
A single PDF (~9 MB): 
`_00Leonardo-s-spatial_grammar_trittico_21_08_2026.pdf`

Earlier versions exist (v1: 7 June 2026; v2: 9 June 2026). The concept DOI that always resolves to the latest version is 10.5281/zenodo.20578821.