问题
Since character movement is grid based, characters look a bit odd when going from square to square as they just appear from one square onto another. To make the movement feel more natural, I wanted to add "afterimages" so that there would be a simulation of smooth movement.
Demonstrational image: Since my code has characters moving directly onto the next square, I don't know how to blit sprites in between.
if IDO.get_key(pygame.K_RIGHT):
if PhaseFocus == 0 or PhaseFocus == 2:
Reticlex +=1
if Currently_Selected != 0 and Currently_Selected.Phase == 2:
if Currently_Selected.x != Reticlex:
Currently_Selected.x = Reticlex
if Currently_Selected.x != Reticley:
Currently_Selected.y = Reticley
if IDO.get_key(pygame.K_LEFT):
if PhaseFocus == 0 or PhaseFocus == 2:
Reticlex -=1
if Currently_Selected != 0 and Currently_Selected.Phase == 2:
if Currently_Selected.x != Reticlex:
Currently_Selected.x = Reticlex
if Currently_Selected.x != Reticley:
Currently_Selected.y = Reticley
When the currently selected character is in Phase 2 (carried around) they should have these afterimages.
回答1:
Let's see how we can do this.
Step 1: Basic setup
We start with an "empty" pygame game, like this:
import pygame
def main():
screen = pygame.display.set_mode((640, 480))
clock = pygame.time.Clock()
while True:
events = pygame.event.get()
for e in events:
if e.type == pygame.QUIT:
return
screen.fill((30, 30, 30))
pygame.display.flip()
clock.tick(60)
if __name__ == '__main__':
main()
We have a Clock, a single game loop and handle the QUIT event. I always store the events from event.get() in a variable in case I want to iterate over them again, e.g. when a Sprite wants to listen for an event. Always call event.get() only once per frame!
Step 2: A grid
We want a grid based game, so let's draw a grid. Also, we store a bunch of Rects in a list so it will be easy for us to lookup the screen coordinates of an object. We want to center objects in their tile, so using the Rect class will do the dirty work for us.
import pygame
TILESIZE = 32
GRID_W, GRID_H = (20, 15)
def create_grid():
surf = pygame.Surface((TILESIZE * GRID_W, TILESIZE * GRID_H))
surf.set_colorkey((2, 2, 2))
surf.fill((2, 2, 2))
grid = []
for y in range(GRID_H):
line = []
for x in range(GRID_W):
r = pygame.Rect(x * TILESIZE, y * TILESIZE, TILESIZE, TILESIZE)
line.append(r)
pygame.draw.rect(surf, pygame.Color('grey'), r, 1)
grid.append(line)
return grid, surf
def main():
screen = pygame.display.set_mode((TILESIZE * GRID_W, TILESIZE * GRID_H))
clock = pygame.time.Clock()
grid, grid_surf = create_grid()
while True:
events = pygame.event.get()
for e in events:
if e.type == pygame.QUIT:
return
screen.fill((30, 30, 30))
screen.blit(grid_surf, (0, 0))
pygame.display.flip()
clock.tick(60)
Step 3: Something's moving on the grid
We now create an actor that travels on this grid. In this case it's a simple Sprite that moves every second.
import pygame
import random
TILESIZE = 32
GRID_W, GRID_H = (20, 15)
LOOKUP = None
class Actor(pygame.sprite.Sprite):
def __init__(self, grid_pos):
super().__init__()
self.image = pygame.Surface((TILESIZE // 2, TILESIZE // 2))
self.rect = self.image.get_rect()
self.pos = pygame.Vector2()
self.update_pos(grid_pos)
self.image.fill(pygame.Color('dodgerblue'))
self.timeout = 1000
def update_pos(self, grid_pos):
self.grid_pos = grid_pos
self.rect.center = get_grid_rect(grid_pos).center
self.pos = pygame.Vector2(self.rect.topleft)
def move_random(self):
d = random.choice([-1, 1])
x, y = self.grid_pos
if random.randint(0, 2):
x += d
else:
y += d
self.update_pos((x, y))
def update(self, events, dt):
self.timeout -= dt
if self.timeout <= 0:
self.timeout = 1000
self.move_random()
def get_grid_rect(pos):
x, y = pos
return LOOKUP[y][x]
def create_grid():
surf = pygame.Surface((TILESIZE * GRID_W, TILESIZE * GRID_H))
surf.set_colorkey((2, 2, 2))
surf.fill((2, 2, 2))
grid = []
for y in range(GRID_H):
line = []
for x in range(GRID_W):
r = pygame.Rect(x * TILESIZE, y * TILESIZE, TILESIZE, TILESIZE)
line.append(r)
pygame.draw.rect(surf, pygame.Color('grey'), r, 1)
grid.append(line)
return grid, surf
def main():
screen = pygame.display.set_mode((TILESIZE * GRID_W, TILESIZE * GRID_H))
dt, clock = 0, pygame.time.Clock()
grid, grid_surf = create_grid()
global LOOKUP
LOOKUP = grid
sprites = pygame.sprite.Group(Actor((9, 6)))
while True:
events = pygame.event.get()
for e in events:
if e.type == pygame.QUIT:
return
sprites.update(events, dt)
screen.fill((30, 30, 30))
screen.blit(grid_surf, (0, 0))
sprites.draw(screen)
pygame.display.flip()
dt = clock.tick(60)
if __name__ == '__main__':
main()
Step 4: Smooth movement
Instead of always drawing the Actor that the center of the tiles, we set a target_grid_pos when we want to move. Each frame, we move the Actor a little bit until we reached our target tile. We use pygame's Vector2 class and it's lerp and distance_to methods.
import pygame
import random
TILESIZE = 32
GRID_W, GRID_H = (20, 15)
LOOKUP = None
class Actor(pygame.sprite.Sprite):
def __init__(self, grid_pos):
super().__init__()
self.image = pygame.Surface((TILESIZE // 2, TILESIZE // 2))
self.rect = self.image.get_rect()
self.pos = pygame.Vector2()
self.update_pos(grid_pos)
self.image.fill(pygame.Color('dodgerblue'))
self.timeout = 1000
def update_pos(self, grid_pos):#
self.target_pos = None
self.target_grid_pos = None
self.grid_pos = grid_pos
self.rect.center = get_grid_rect(grid_pos).center
self.pos = pygame.Vector2(self.rect.center)
def move_random(self):
d = random.choice([-1, 1])
x, y = self.grid_pos
if random.randint(0, 2):
x += d
else:
y += d
self.target_pos = pygame.Vector2(get_grid_rect((x, y)).center)
self.target_grid_pos = (x, y)
def update(self, events, dt):
self.timeout -= dt
if self.timeout <= 0:
self.timeout = 1000
self.move_random()
if self.target_grid_pos:
self.pos = self.pos.lerp(self.target_pos, 0.1)
if self.pos.distance_to(self.target_pos) < 1:
self.update_pos(self.target_grid_pos)
self.rect.center = self.pos
def get_grid_rect(pos):
x, y = pos
return LOOKUP[y][x]
def create_grid():
surf = pygame.Surface((TILESIZE * GRID_W, TILESIZE * GRID_H))
surf.set_colorkey((2, 2, 2))
surf.fill((2, 2, 2))
grid = []
for y in range(GRID_H):
line = []
for x in range(GRID_W):
r = pygame.Rect(x * TILESIZE, y * TILESIZE, TILESIZE, TILESIZE)
line.append(r)
pygame.draw.rect(surf, pygame.Color('grey'), r, 1)
grid.append(line)
return grid, surf
def main():
screen = pygame.display.set_mode((TILESIZE * GRID_W, TILESIZE * GRID_H))
dt, clock = 0, pygame.time.Clock()
grid, grid_surf = create_grid()
global LOOKUP
LOOKUP = grid
sprites = pygame.sprite.Group(Actor((9, 6)))
while True:
events = pygame.event.get()
for e in events:
if e.type == pygame.QUIT:
return
sprites.update(events, dt)
screen.fill((30, 30, 30))
screen.blit(grid_surf, (0, 0))
sprites.draw(screen)
pygame.display.flip()
dt = clock.tick(60)
if __name__ == '__main__':
main()
Step 5: Adding the effect
Every 300 ms, we create a copy of the Actor's image, blit it at the Actor's position, and make sure to delete it after 200ms. In a real game, you probably want to cache the images or use pre-rendered ones.
I switched the Group for LayeredUpdates so we can make sure the original images is always drawn above the "shadows".
I also added an image (from rltiles) instead of a simple rect so it looks nicer in this demo.
import pygame
import random
import gzip
import base64
TILESIZE = 64
GRID_W, GRID_H = (10, 7)
LOOKUP = None
class Shadow(pygame.sprite.Sprite):
def __init__(self, source):
super().__init__()
self._layer = 5
self.image = source.image.copy().convert_alpha()
self.image.fill((0, 0, 200, 100), special_flags=pygame.BLEND_ADD)
self.rect = source.rect.copy()
self.timeout = 200
def update(self, events, dt):
self.timeout -= dt
if self.timeout <= 0:
self.kill()
class Actor(pygame.sprite.Sprite):
def __init__(self, grid_pos):
super().__init__()
self._layer = 10
data, size = gzip.decompress(base64.b64decode(HYDRA)), (64, 64)
self.image = pygame.image.fromstring(data, size, "RGB")
self.image.set_colorkey((71, 108, 108))
self.rect = self.image.get_rect()
self.pos = pygame.Vector2()
self.update_pos(grid_pos)
self.timeout = 1000
self.shadow_timeout = 100
def update_pos(self, grid_pos):#
self.target_pos = None
self.target_grid_pos = None
self.grid_pos = grid_pos
self.rect.center = get_grid_rect(grid_pos).center
self.pos = pygame.Vector2(self.rect.center)
def move_random(self):
d = random.choice([-1, 1])
x, y = self.grid_pos
if random.randint(0, 2):
x += d
else:
y += d
self.target_pos = pygame.Vector2(get_grid_rect((x, y)).center)
self.target_grid_pos = (x, y)
def update(self, events, dt):
self.timeout -= dt
if self.timeout <= 0:
self.timeout = 1000
self.move_random()
if self.target_grid_pos:
self.shadow_timeout -= dt
if self.shadow_timeout <= 0:
self.shadow_timeout = 100
self.groups()[0].add(Shadow(self))
self.pos = self.pos.lerp(self.target_pos, 0.1)
if self.pos.distance_to(self.target_pos) < 1:
self.update_pos(self.target_grid_pos)
self.rect.center = self.pos
def get_grid_rect(pos):
x, y = pos
return LOOKUP[y][x]
def create_grid():
surf = pygame.Surface((TILESIZE * GRID_W, TILESIZE * GRID_H))
surf.set_colorkey((2, 2, 2))
surf.fill((2, 2, 2))
grid = []
for y in range(GRID_H):
line = []
for x in range(GRID_W):
r = pygame.Rect(x * TILESIZE, y * TILESIZE, TILESIZE, TILESIZE)
line.append(r)
pygame.draw.rect(surf, pygame.Color('grey'), r, 1)
grid.append(line)
return grid, surf
def main():
screen = pygame.display.set_mode((TILESIZE * GRID_W, TILESIZE * GRID_H))
dt, clock = 0, pygame.time.Clock()
grid, grid_surf = create_grid()
global LOOKUP
LOOKUP = grid
sprites = pygame.sprite.LayeredUpdates(Actor((4, 3)))
while True:
events = pygame.event.get()
for e in events:
if e.type == pygame.QUIT:
return
sprites.update(events, dt)
screen.fill((30, 30, 30))
screen.blit(grid_surf, (0, 0))
sprites.draw(screen)
pygame.display.flip()
dt = clock.tick(60)
HYDRA = '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'
if __name__ == '__main__':
main()
来源：https://stackoverflow.com/questions/57029253/how-to-add-afterimages-in-pygame