geometry

Documentation

Index

• func CalcAngleBetweenPoints(x1, y1, x2, y2 float64) float64
• func CalcDistance(x1, y1, x2, y2 float64) float64
• func CalcWeaponFireAngle(curX, curY, bulletSpeed, enemyX, enemyY, enemySpeed, enemyRotation float64) (angle float64, targetX float64, targetY float64)
• func IsPointInRotatedRectangle(x, y, cx, cy, length, width, angle float64) bool

Functions

func CalcAngleBetweenPoints

func CalcAngleBetweenPoints(x1, y1, x2, y2 float64) float64

ebiten 游戏引擎坐标体系： | ^ y | -3 | | -2 | | -1 | 1 2 3 x ------------+------------> | -3 -2 -1 | 1 | | 2 | | 3

CalcAngleBetweenPoints 计算两个点之间的夹角（+90 转换成顺时针角度, +360 确保非负数）

func CalcDistance

func CalcDistance(x1, y1, x2, y2 float64) float64

CalcDistance 计算两个点之间的距离

func CalcWeaponFireAngle

func CalcWeaponFireAngle(
	curX, curY, bulletSpeed, enemyX, enemyY, enemySpeed, enemyRotation float64,
) (angle float64, targetX float64, targetY float64)

CalcWeaponFireAngle 计算武器发射角度

func IsPointInRotatedRectangle

func IsPointInRotatedRectangle(x, y, cx, cy, length, width, angle float64) bool

示例：length 4, width 1, angle 0

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| | | | 3 | |

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1

示例：length 4, width 1, angle 90

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| | 1

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  3

IsPointInRotatedRect 判断点 (x, y) 是否在由中心点 (cx, cy)，旋转角度 angle，长度 length 和宽度 width 的长方形内