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The 3D photo-realistic model is characterized by high accuracy and large data volume. When visualizing these data in GIS applications, the whole model will be tiled and pyramid for efficient network transferring and loading. Then the tile loading strategy based on the distance from the viewpoint (hereinafter referred to as “the distance-based strategy”) will lead to the tiles appearing at the edge of the screen own better visual quality and large volume compared with those in the center of the screen, which mostly been the primary area that attracts human attention. To address this data redundancy problem, this paper proposes a novel tile loading strategy method based on the human eye's area of interest which provides better visualization quality on the central area of the screen while keeping the overall data volume loading on the web. Compared to the distance-based methods, the proposed method considering the angular deflection of the direction from the camera position to the center of the tile and the LOS (light of sight) direction, and recalculating the screen space error (SSE) determines which tiles in the pyramid will be selected. This method can choose higher-resolution tiles for the center region and choose lower-resolution tiles for the marginal region simultaneously. The experimental results show it increases the screen resolution of the center area while keeping the memory occupation steady. This research can facilitate the applications of 3D photo-realistic models in digital cities.
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