Building envelope determination

摘要

Methods, systems, and apparatus, including computer programs encoded on a computer storage medium, for determining a building envelope. In one aspect, a method includes generating two-dimensional analytical faces; generating a three-dimensional shell bounding box that encompasses the analytical faces; determining, for each analytical face, one or more sample points; performing a flood-fill algorithm from a reference grid cell through other grid cells in the shell bounding box; casting one or more primary rays from each grid cell encountered by the flood-fill algorithm that does not contain any of the sample points but that directly neighbors a grid cell that does contain a sample point; for each ray, identifying as an exterior face the first analytical face within a vicinity of the grid cell from which the ray is cast that is intersected by the ray; and generating a building envelope based on the identified exterior faces.

主权项

1. A method performed by data processing apparatus, the method comprising:
generating a respective two-dimensional analytical face to represent each bounding element of a plurality of bounding elements that form at least a part of an analytical model; generating a three-dimensional shell bounding box that encompasses the analytical faces, the shell bounding box further comprising a plurality of three-dimensional grid cells arranged within the shell bounding box; determining, for each analytical face, one or more sample points on the analytical face; performing a flood-fill algorithm from a reference one of the grid cells through other ones of the grid cells in the shell bounding box; casting one or more primary rays from each one of the grid cells encountered by the flood-fill algorithm that does not contain any of the sample points but that directly neighbors one or more other ones of the grid cells that do contain one or more of the sample points; for each casted primary ray, identifying as an exterior face the first analytical face within a vicinity of the grid cell from which the primary ray is cast that is intersected by the casted primary ray; and generating a building envelope based on the identified exterior faces.