Ch: jiehua. Lit. boundary painting. Both a painting technique and a painting genre in China. As a technical term, kaiga refers to the use of a straight edge or compass for the precise rendering of man-made objects, such as architecture, boats, and wagons. The technique seems to have originated very early in the need of artisans and builders for accurate mechanical and architectural drawings. One of the earliest extant uses of the technique is found in the wall-paintings of the tomb of Crown Prince Yide (Jp: Itoku taishi 懿徳太子) dated 706 in Shaanxi 陜西 Province. The careful renderings of realistic architectural and mechanical detail can be seen in paintings (sometimes referred to as okubokuga 屋木画) of many Chinese artists. The term kaiga is applied as a genre, however, only to the meticulous lines and requisite skill found in the work of certain professional non-literati painters. The 12th-century handscroll Spring Festival of the River, Chingming shanghe (Jp: Seimei jōka 清明上河) by Zhang Zeduan (Jp: Chō Takutan 張択端) in the Palace Museum, Beijing, is a representative example. In Japan, a similar technique called yataibiki 屋台引 was used extensively for the depictions of architecture in picture scrolls *emaki 絵巻 of the Heian period, although paintings employing the yataibiki technique were not considered as a separate genre.