Abstract: Raising the digital sand table at a certain tilt angle according to the site environment helps to enhance the viewing experience of the physical sand table and projection content. However, the projection content is prone to offset after the sand table is tilted, resulting in the original content can not be projected to the corresponding position. In order to address this problem, this paper proposes an adaptive projection algorithm. Firstly, the original pixel matrix is established by the projected content and the environment parameters. And coordinate corrected models are established for different projected positions. Then the new coordinate positions after tilting are calculated by traversing the pixel points. Finally, the corrected pixel matrix is obtained by assigning the color value of each point to the new point, achieving adaptive projection. The experimental results show that the algorithm can ensure that the original projection content is accurately projected onto the sand table.

Key words: tilt angle, adaptive, coordinate corrected model, pixel matrix