[Pygame] Math Vector 파이게임 수학 벡터

파이게임 수학 벡터 함수 중 유용한 내용.

 

import pygame
import math
 
pygame.init()
pygame.display.set_caption("Super fun game development")
screen = pygame.display.set_mode((640, 480))
clock = pygame.time.Clock()
 
# pygame.math.Vector2.rotate
# rotates a vector by a given angle in degrees.
 
# pygame.math.Vector2.rotate_rad
# rotates a vector by a given angle in radians.
 
vec = pygame.math.Vector2(math.sqrt(2), 0)
print(vec.rotate(45))
# (sqrt(2), 0) 벡터를 반시계방향으로 45도 회전한 벡터.
# 벡터의 길이는 그대로 유지된다.
 
v1 = pygame.math.Vector2(300, 400)
 
# project(Vector2) -> Vector2
# Returns the projected vector. This is useful for collision
# detection in finding the components in a certain direction.
# (e.g. in direction of the wall).
v2 = v1.project(pygame.math.Vector2(1, 0))
print(v2)
# (3, 4) 벡터가 X축(1, 0)에 투영되었을 때의 벡터.
 
v3 = v1.project(pygame.math.Vector2(0, 1))
print(v3)
# (3, 4) 벡터가 Y축(0, 1)에 투영되었을 때의 벡터.
 
running = True
 
while running:
    for event in pygame.event.get():
        if event.type == pygame.QUIT:
            running = False
        elif event.type == pygame.KEYDOWN and event.key == pygame.K_ESCAPE:
            running = False
 
    screen.fill("black")
 
    pygame.draw.line(screen, "red", (0, 0), v1, 20)
    pygame.draw.line(screen, "green", (0, 0), v2, 20)
    pygame.draw.line(screen, "blue", (0, 0), v3, 20)
 
    pygame.display.flip()
 
    clock.tick(60)
 
pygame.quit()

 

 

벡터의 회전(rotate)과 투영(project)

 

 

Project

 

Projection of a on b (a1), and rejection of a from b (a2).

 

When 90&deg; < &theta; &le; 180&deg;, a1 has an opposite direction with respect to b.