如何优化此代码的性能？

Question

I'm making a game in pygame, the full source code of which can be found here:

https://github.com/hailfire006/games/blob/master/strategy%20game

Unfortunately, I'm running into some frame rate issues and everything I've read about this sort of problem says it's graphical, ie it's got nothing to do with the math and everything to do with drawing the sprites.

As such, I've narrowed the problem down to the following draw function of my npc class, which is called every frame for every npc in my "objects" list. It's got a lot of sprite rotation, a set_colorkey, and a re-sizing. All of these things are probably quite costly, so is there a way I can re-write the following code to optimize it for performance?

PS: Sorry if what I'm asking or bits of the code are unclear, point it out if something is confusing and I'll edit my question.

b = pygame.sprite.Sprite()
b.image = pygame.image.load("soldier.png").convert()
b.image.set_colorkey((0,0,0))

target = get_target(self)
if target != 0:
    angle = math.degrees(math.atan2(self.x - target[0], self.y - target[1])) + 90
    b.image = pygame.transform.rotate(b.image,angle)
    self.shoot(target)

if self.moving != False:
    if abs(self.x - self.moving[0]) < 1 and abs(self.y - self.moving[1]) < 1:
        self.moving = False
    else:
        self.move(self.moving)
        if target == 0:
            angle = math.degrees(math.atan2(self.x - self.moving[0],                   self.y - self.moving[1])) + 90
            b.image = pygame.transform.rotate(b.image,angle)

b.image = pygame.transform.smoothscale(b.image,(50,50))
b.rect = b.image.get_rect()
b.rect.topleft = [self.x - 20, self.y - 20]
window.blit(b.image, b.rect)

Answer 1

Woah woah woah... are you loading and converting that .png every frame?

1. Don't do that.

Next up, instead of returning 0 from get_target, I recommend returning None. Then your next line can be:

if target is not None:

Which is slightly faster.

Next time, try and profile each segment of your code. You can use python's profiling tools to have a look at your code in detail, or just write your own simple timer controller .