Python/Pygame.. Trouble w/ classes

Question

Hey guys I have some issues while I was making my game.... I want to move my character while the image changes every "step" that it looks like an animation...

I haven been working on this for hours but the only thing I have done so far is to move the char but all images are drawn at once while moving

keys = pygame.key.get_pressed()
if keys[pygame.K_LEFT]:
    currentimageleft = 1
    gamedisplay.blit(background, (0,0))
    if currentimageleft == 1:
        gamedisplay.blit(temp1, (template_x, template_y), (g1x, g1y, box, box))
        template_x -= moveit
        currentimageleft += 1
    if currentimageleft == 2:
        gamedisplay.blit(temp1, (template_x, template_y), (g2x, g2y, box, box))
        template_x -= moveit
        currentimageleft += 1
    if currentimageleft == 3:
        gamedisplay.blit(temp1, (template_x, template_y), (g3x, g3y, box, box))
        template_x -= moveit
        currentimageleft += 1
    if currentimageleft == 4:
        gamedisplay.blit(temp1, (template_x, template_y), (g4x, g4y, box, box))
        template_x -= moveit
        currentimageleft = 1
    pygame.display.update()

here is a link to see what it looks like: https://www.flickr.com/photos/130707619@N05/ — Fur-gan, Feb 22 '15 at 20:51
Is it possible, that you just add the change split to your screen without refreshing background? — frlan, Feb 22 '15 at 20:53
Could you please describe a bit more what you mean by adding the change split.. — Fur-gan, Feb 22 '15 at 20:55

score 1 · Answer 1 · answered Feb 22 '15 at 20:53

1

Use elif for the subsequent comparisons, so that only one is done per iteration.

answered Feb 22 '15 at 20:53

Daniel Roseman

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now he moves forward but only with one of the images :( – Fur-gan Feb 22 '15 at 20:57

score 0 · Accepted Answer · edited May 23 '17 at 12:20

Since you are incrementing currentimgeleft in each of your if blocks, it then triggers the next if block down the line. You only want one to trigger each frame, so switch the if to elif for all but the first one and then you'll have only one triggering each time the K_LEFT button is pressed on the keyboard. Like so

if currentimageleft == 1:
    # code
elif currentimageleft == 2:
    # code
...

However, notice that you are setting currentimageleft each time you enter the bigger if statement for the keypress. This will ensure that you always end up using the very first sprite of your animation. You may want to associate currentimageleft with a class variable by declaring it in __init__ to be something like

def __init__(self, ...):
    # other code, including possible parent constructors
    self.currentleftimage = 1
    # more code

You would then access your variable with self.currentimageleft instead of currentimageleft. This would then allow you to use else or elif clauses on your button press detection (the outer if in your code snippet) to reset the self.currentleftimage variable back to 1 allowing you to track motion that way instead.

You may also find this other answer on the equivalent form of switch in Python interesting, though several calls to elif clauses is also perfectly normal and may lead to more legible code in many cases.

Thx a lot bro! It worked fine!!! :D Didn´t notice that because of the "while-loop" it always gets back to 1 T_T — Fur-gan, Feb 22 '15 at 21:10
@TofuDaydreamer You are quite welcome. Glad to be of service. :) — BobChao87, Feb 22 '15 at 21:52

Python/Pygame.. Trouble w/ classes

2 Answers2