Memory, night scene light texture drawing method, system and device

The invention discloses a memory, and a night scene light texture drawing method, system and device. The method comprises the following steps: generating a plurality of bitmap self-luminous textures consistent with the resolution of diffuse reflection textures on the preset side surface of a building model; converting the bitmap self-luminous textures into directed self-luminous textures and generating a texture library; when a building model grid is constructed, allocating a position random number in a two-dimensional coordinate form to the building model, and determining a sampling positionin a preset random texture by taking the position random number as a coordinate point; taking the sampling position as a starting point, performing pixel sampling in the random texture according to the row number and the column number of the window area on the preset side surface, and obtaining a first channel pixel value and a second channel pixel value of a random pixel corresponding to each window area; determining dir