Pygame (Python Game Development) Tutorial - 4 - Quit Event Handling Video Lecture | Pygame (Python Game Development): Create Awesome Games - Front-End Programming

what's going on everybody welcome to the
fourth packing tutorial from centex and
for Bucky at the new Boston where we
left off we've got our PI game it's
shown up on the screen
we've titled it slither we know it's
going to be epic we've got a simple game
loop it's a while loop needs to be
improved a little bit but it works and
we're printing out basically all the
events that a user puts in just so we
can get an idea now actually here what
most people use are key press events but
there's actually a huge multitude of
events and for that I'm going to show
you guys the source of the hugging
documents here and where's this tape ok
it's down here and just as a quick aside
I know a lot of people don't like to
read the documents to the modules or
really basically read the instructions
to anything one of those people but I
must admit that at least with PI game
and quite a few of the other Python
modules the documents are really good
and really useful so I highly suggest it
with that this we're going to head to PI
game org slash Doc's /r f / event HTML
you don't have to actually go there if
you don't want I'm just going to show
you guys though these are all of the
events that can possibly happen so we
have a quit event we have active event
basically our is the screen active is it
unactive and then also you see gain and
state the gain is like the transition
between active and inactive and then
you've got state which is is it active
or is inactive so you might have an
active state that just became active so
that's a state you might have an active
state that's been active you might have
an inactive state you might have an
inactive state that just became inactive
so what do we want to do so then we have
keydown and keyup and basically this is
just going to return the key in any mods
and all that Mouse motion it's going to
give you the position all that you've
got mouse button up mouse button down
you also have joystick support I have
not seen any money supporting joysticks
in their PI game
there's probably someone someone
somewhere that did it but I have not
seen it and then you have video resize
video expose let's see video expose
would be I think just drawing to the
screen the video resize is basically
when there it's an event where the user
themselves resizes the window so what
you can do is you can have support for
say the users resizing the window you
can resize everything in exactitude
compared to how did the user resize the
window so if they resize the width by
80% you can resize the width of
everything by 80% height same thing and
that's pretty much it you can have user
event as well but let's not touch that
for now so those are all of the events
that can be handled via PI game so I'm
not exit out of this from hospital up
here actually just in case we wanted
again those are all the events now
here's how you can handle a very simple
event um like an exit so we don't have
any way to exit our game yet and this
will be pretty much non I said before we
showed you the skeleton this is the true
skeleton because you're pretty much
going to see this but you won't see the
exact same code right a lot of people
aren't going to maybe a lot of people
prior not using a while loop but this is
probably more so the skeleton that
you'll see on almost every game so for
vamp I gained out event I get you can
print the event I'm gonna stop doing
that now um and now we're going to say
um if event dot type an event dot type
is these events here so is that event
dot type a quit active event keydown
keyup mass motion all that those are all
the events that could possibly be if the
event dot type equals and then to
reference these right quit for example
to reference that it's a it's a PI game
event so how would you reference that
you can't just say quit you'd have to
say PI game quit because we've imported
PI game so for example if event dot type
equals PI game dot quit what do we want
to do well here oops I forgot my colon
colon
um and actually this is an object so no
parameters there so if the event type is
a PI game quit uh uh type and this needs
to be all caps I'm all over the place
mmm there we go
so if it's a quit event what do we want
to do well we need to quit and just to
be in in with our code here we're going
to say it's that we're going to just
call game exit equals trip true and it's
get rid of this and so when game exit
equals true that invalidates this while
loop it will stop running and then we'll
run this PI game quit and then quit so
let's go ahead and save and run that
pops up we got slither we can do
whatever the heck we want and I see a
dead pixel on my screen anyway you can
exit out and that's it so now the
exiting actually is hand-tooled and we
don't have to exit out with the script
itself now like I was saying before
watch the first let's talk real briefly
we aren't change this for sure because
for example you've got game exit and
then you've actually got like a quick
game right so a lot of times when you
quit a game they send you to the main
main menu so so you can either play
again or whatnot or like when you die
you leave the game so to speak but you
don't necessarily want to like make the
user quit the game entirely how annoying
would that be so you want to let the
user continue playing if they want so
you'd have like two different handlings
right you've got a a game loss and then
you've got a game exit so you this is a
game exit so if they quit we definitely
want to do plug in a quit but if they
like I don't know crash into the wall or
something that's a different exit
entirely so eventually like I say we
will have a main loop but for now we'll
just leave it leave it like this
so what you'll tend to see as as time
goes on we'll be adding more events but
basically you'll have stuff like this
like event type equals plug and equip
blah you have some other event types and
it won't be probably gonna quit but
it'll be like key up key down that kind
of stuff you have a bunch of these
asking questions basically
was this was that was it something else
all that and then if that's the case we
run a function and then usually down
below you got some sort of logic for
updating the actual graphics themselves
and then you run an actual update
function which right now is going to do
pretty much nothing because we don't
have um any sort of frames per second
set up but we will get to that
so anyway your first event handling that
was very easy it's very nice that PI
game has this built in for us actually
acquiring events from the users keyboard
or from the users Mouse position all
that it requires quite a bit of coding
and that kind of coding is not really
that fun it's not enjoyable and it has
almost nothing to do with your game so
that's what makes Pi game really nice is
that it kind of handles the stuff that
we really just don't want to do so
hopefully you guys enjoyed and stay
tuned to the next video