Re: [pygame] newbie

Love, tullarisc.

2010/3/26 <snet-1@xxxxxxx>

These are gems Kris, thanks, if I had to figure all this out by trial &
error, i'd still be here till next millenium not have a beta churned out!

some one mentioned to look at the mvc on another mailing list which is what
i'm trying to follow, it kinda makes sense but my learning resources are
limited to the internet at the minute. I have been reading through the codes of the games on pygame to get an idea of how it works thought they can be quite difficult to follow & find how they have structured it, if anyone feels the need to write a really simplified game & put it up on pygame........... :.P

The variables have no specific meaning bar easy reference as the numpad on
my keyboard has arrows on it.

I haven't had a chance to read through your sudjestions yet (on the books 2nite) but I will get back with more Q's (if that's cool.

If anyone's interested, Py Em Up has a really interesting way of levelmakeing using bmp images

--------------------------------------------------
From: "Kris Schnee" <kschnee@xxxxxxxxxx>
Sent: Thursday, March 25, 2010 11:20 PM

To: <pygame-users@xxxxxxxx>
Subject: Re: [pygame] newbie

On 3/25/2010 6:03 PM, snet-1@xxxxxxx wrote:

Ah, yes I see what's happening, the last time I was doing it I was using:
...........KEYDOWN:
if event.key == K_LEFT:
foreward = True
...........KEYUP:
if event.key == K_LEFT:
foreward = False
meaning it was staying true, until key up but now it's not keeping the
output next time round & waiting for it again.
could you elaborate on this bit 'You could make the character move every
frame (eg. setting a speed and
moving by that speed per frame) until a KEYUP event happens', or is that
pretty much what I 'was' doing?

If you said, "On a KEYDOWN event, set speed to N and set direction to
whatever; and on a KEYUP event, stop," then the result should be that the
character keeps moving until you let go of the key. If you said, "On a
KEYDOWN event, move," then you should get one frame of movement each time
you press (not hold) the key.

My advice is to figure out what the player's trying to do first, like
"move right", and then actually execute the movement in a separate bit of
code ("if moving right..."). That's useful for things like replacing what
keys do what, or having some non-interactive event steer the character.

Could I use "keys_down = pygame.key.get_pressed" then
"if keys_down[K_RIGHT] ## move right",

in this way:
class character():
................
def update(self, d, sp):
if d == 6:
self.x += sp
elif d == 4:
self.x -= sp
elif d == 8:
self.y -= sp
elif d == 2:
self.y += sp

Why use this odd numeric-keypad code for the direction? Other than the
variable names and that code, this looks usable. But think about what'd
happen if I pressed RIGHT and UP at the same time: the code would see the
RIGHT, set the direction to right, then probably see the UP (depending on
which was mentioned last in the code) and change the direction to up.

A different way to handle the movement would be something like:
player.coords = [42,100] ## some starting value
## In a loop:
movement = [0,0]
if keys_down[K_RIGHT]:
movement[0] = speed
...
if keys_down[K_UP]:
movement[1] = speed
...
player.move(movement)

def Move(movement):
self.coords[0] += movement[0]
self.coords[1] += movement[1]

You'd then get diagonal movement, and not have to specify the direction,
and could apply effects like muddy ground multiplying the X and Y movement
by .5 or something. The actual diagonal speed would be sqrt(2) * speed
though, which might matter.

def controls():

output = 0
keysDown = pygame.key.get_pressed():

Why is there a colon after the function call? That's only for defining it.

Are you familiar with the "Model/View/Controller" style of organizing a
game, by the way? It's similar to what you're doing, and pretty useful.