官术网_书友最值得收藏!

Introducing vectors

What is a vector? A vector is an n-tuple of numbers. It represents a displacement measured as a magnitude and a direction. Each element of a vector is usually expressed as a subscript, such as (V0, V1, V2, … VN). In the context of games, vectors usually have two, three, or four components.

For example, a three-dimensional vector measures displacement on three unique axes: x, y, and z. Elements of vectors are often subscripted with the axis they represent, rather than an index. (VX, VY, VZ) and (V0, V1, V2) are used interchangeably.

When visualizing vectors, they are often drawn as arrows. The position of the base of an arrow does not matter because vectors measure displacement, not a position. The end of the arrow follows the displacement of the arrow on each axis.

For example, all of the arrows in the following figure represent the same vector:

Figure 2.1: Vector (2, 5) drawn in multiple locations

Figure 2.1: Vector (2, 5) drawn in multiple locations

Each arrow has the same length and points in the same direction, regardless of where it is positioned. In the next section, you will start to implement the vector structure that will be used throughout the rest of this book.

主站蜘蛛池模板: 正定县| 成武县| 宿迁市| 洪雅县| 龙州县| 淮滨县| 东平县| 壶关县| 拉萨市| 抚州市| 宜兰市| 静乐县| 内乡县| 平泉县| 遂溪县| 绥芬河市| 龙江县| 汕头市| 贡觉县| 平度市| 若羌县| 永嘉县| 广安市| 新源县| 洪洞县| 高淳县| 云梦县| 额尔古纳市| 贡觉县| 共和县| 大名县| 陵水| 登封市| 吉水县| 东山县| 建湖县| 海兴县| 兴义市| 章丘市| 洪洞县| 岗巴县|