摘要 |
<p>More reality is given to weather phenomena reflected on an image displayed on a screen of a display unit and on operability of an operatable object. A global weather deciding part 901 decides weather in each global area obtained by dividing the whole map of a virtual world into a plurality of global areas. The weather in the global area in question is decided at intervals of a first time, in accordance with a preset behavior model and considering area information of each global area in advance. A local weather deciding part 902 decides weather in each local area obtained by dividing each global area into a plurality of local areas. The weather in the local area in question is decided at intervals of a second time, which is shorter than the first time, in accordance with the weather of the global area concerned decided by the global weather deciding part 901, and considering area information of each local area.</p> |