Three-dimensional city model rendering method and device

Abstract

The present invention provides a three-dimensional city model rendering method and device. The method includes the following steps that: a preset range model is set, and a preset range model-based quadtree index is constructed according to the bounding boxes and rendering levels of each three-dimensional city model included in the preset range model; a model subset is obtained according to the position of a current point of sight and the quadtree index, the model subset is processed and updated into a scene tree, and a corresponding visible distance is set for each model loading type of each model according to the rendering level of each model; and each node of the scene tree is traversed, and a model loading type satisfying a loading condition is selected according to the distance of the current point of sight so as to load and render a model corresponding to a current node. With the advantage of high query efficiency of the quadtree utilized, and the complexity of the models considered, important three-dimensional city models can be loaded preferentially, and minor models can be loaded later, and therefore, the model loading order better accords with visual habits of human, and model rendering efficiency and rendering fluency are high.

Description

technical field [0001] The present invention relates to the technical field of three-dimensional models, in particular to a method and device for rendering a three-dimensional city model. Background technique [0002] With the rapid development of traditional surveying and mapping industry technology, the application fields of 3D digital city models are becoming wider and wider, and have developed from the roaming browsing of a single community or small scene to the 3D application of the entire city. With the continuous improvement of technology, the accuracy of the model and the simulation degree of the model have been greatly improved. However, the improvement of the accuracy and the degree of simulation has also brought about a problem: the dramatic increase in the amount of data. The number of urban building models in the 3D digital city scene is huge and the structure is complex. In real-time scene rendering, it is unrealistic to load all the city models into the comput...

AI Technical Summary

Problems solved by technology

With the continuous improvement of technology, the model accuracy and model simulation degree have been greatly improved. However, the improvement of accuracy and simulation degree has also brought about a problem: the dramatic increase in the amount of data

[0004] However, the existing quadtree construction method is only based on the visual distance for rendering and loading, without considering the complexity of the city model, the loading method is not flexible enough, some important city models cannot be loaded first, and the waiting time for loading is longer

Moreover, some models cannot even be loaded and rendered due to poor viewing distance

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