As one of high speeding techniques of image display in an information display control system, there is a technique of using an atlas image (also referred to as a “texture atlas”) in which a plurality of images are unified into one image. Since the plurality of images can be taken out of one texture atlas, the texture atlas is created in advance, whereby a number of readout times of image files is reduced, and a readout time of image data can be shortened.
In an event of creating the texture atlas, it is a challenge to determine how to efficiently arrange the plurality of images, which are different from one another in size, on the texture atlas. In usual, since the images for use in the information display control system are rectangular, this challenge can be handled as a “rectangle packing problem” in which rectangles are arranged on a two-dimensional surface with a fixed area without overlapping one another. A variety of approximate methods are known with regard to the rectangle packing problem. For example, the Best-fit method proposed in following Non-Patent Literature 1 is an algorithm that repeatedly packs rectangles which can use gaps to the maximum.