Modelling the Rongorongo tablets. A new transcription of the Échancrée tablet and the foundation for decipherment attempts

The Rongorongo is a system of writing, still undeciphered, from Easter Island in the Pacific. It consists of a corpus of twenty-six inscriptions, scattered around the world. This article presents the state-of-the art in the study of one of these inscriptions, Text D or the ‘Échancrée’ tablet housed in a museum in Rome, Italy. Through an integrated methodology based on photogrammetry and high-precision structured light scanning, a 3D model of the inscriptions is made available through a public 3D Viewer for the first time. The technique made use of the benefits of both methods of image acquisition: a very accurate, precise, high resolution, and metric reconstruction of the tablet geometry gained through the scanning process, and a high-quality texture achieved through photogrammetry. In addition, we present a new analysis of the text, through a close palaeographic examination of its signs, and corrections of previous hand drawings and transcriptions. The ultimate aim is to reach unbiased ‘readings’ of the signs through an integrated synergy of traditional palaeographic analysis and an advanced 3D model. These, applied to all the inscriptions, constitute the necessary stepping-stones for any decipherment attempt.