Java Game Development - 9 - Changing Scenes Video Lecture | How to create Games in Java - Gaming Development - Software Development

what is going on guys welcome to your
ninth drop a game development tutorial
and in this tutorial we're going to be
learning how to build some more method
that are going to be useful in our
animation so in the les story we built a
method to add a scene and we also bear a
constructor and inside our constructor
we call this start method but we never
actually build it so let's go ahead and
add a comment too and we'll build it
right now what this is going to do is
start and mission from beginning good
enough make sure beginning looks like
Beijing or out your code or not work so
let's go ahead and make our start method
right here
and we'll go public and synchronize void
start so now we can only run this method
before we can run any of a KA
synchronized so what star is going to do
is remember we made two variables called
movie time and total time right here
it's cutting pretty much you're going to
call this whenever you restart your
animation or start it for the first time
so we're going to set that movie time or
your animation time equal to zero right
there so aside from this whenever you
restart your animation you want to make
sure that your scene
index is at zero as well and this means
that pretty much you start at the
beginning of your animation and whenever
you call this method and make sure that
everything is pretty much reset to zero
so that's all that method does start
simple enough and now we need to make a
method to change from seeing the scene
or when one image is up go to the next
scene so let's go ahead and go ahead and
put change scenes good enough and now
we'll name this method update so public
synchronized void and we will name it
update now what this is going to do is
take one parameter long time passed and
what time pass is going to be and don't
worry about the
exactly what it means right now we'll be
creating it later it's pretty much going
to be the time that passes from the last
update since we're going to call this
update many many times and we're going
to keep track of the time that passed
from when I called it this time from the
time I called it last time so let's go
ahead and write a simple if if scenes
dot size in sizes built-in methods so
you don't got to worry about that is
greater than one and if we're saying all
right why do you need to check this well
if you only have one scene that's then
your scene is equal to one then you
don't even have an animation you just
have a picture it is chilling there on
your screen so we only run to run this
code if there's more than one pictures
pretty much um so let's go ahead and do
this the first thing we want to do is
take that movie time in set it equal to
the sum of time tests and what does this
mean in plain terms well the movie time
is pretty much the sum of all the time
that passed from last update so this
time passed is how long does it take to
call these updates from the last update
and store that time and add it to this
movie time right here so it's pretty
much a sum of all the time passed so
pretty much what you're going to get in
the movie time is the total time your
animation has run so now what we can do
that is check for something if movie
time is greater or equal to total time
like that and why do we need to check
for this because we want to make sure
the time of the animation itself does
not exceed the limit that should go and
if it does exceed it if this animation
gets done sooner than this we want to
restart the animation and if we don't
restart it then it's just going to stay
still on that last picture and we don't
want that or else it would be a really
boring movie
so let's just go ahead and what do we
want to restart our animation let's go
ahead and put movie time equal to zero
and also scene index equal to zero and
if you look up here this is pretty much
doing the same thing this this is going
to happen when you start your animation
for the very first time and when it's
running and you need to restart it this
is how you do it so and that is needs to
be capitalized like that so pretty much
when the movie gets done or when the
animation gets done running one loop
restart the animation again and do it
until it gets to the total time then
your movies going to be over so now we
need to make a little thing if the movie
time surpasses well pretty much is
saying when do I go when do I get done
with one picture and go to the other
picture and let's let make a little
while loop for this it will be the
easier if the movie time and remember
this is your animation time is greater
than and this might be kind of confusing
we're going to be building a method
later called get seen and it's pretty
much going to get the picture or the
scene you're on so get seen and I know
we didn't build this yet but stick with
me seen index and this all this is going
to do is get whatever animation you're
on right now and get the end time for it
so well let me think
all right here we're going to do scene
index plus plus what this is saying and
I know it's confusing because we didn't
build this method yet and we're going to
be building in the next tutorial when
you get to the end of one scene go to
the next one so whenever you call a
picture it's going to run for a certain
amount of time whenever you're done and
running that go to the next picture and
do the exact same thing before so that's
what this little while loop checks for
and now our update method is complete
all we have to do is pass in the time
that passed and we'll be checking this
in our other one right here arm
I mean that's that's all we really need
for this tutorial so I know this looks
really confusing but if you just look at
it for like one second and think about
it all it does is pretty much exchange
scenes when it needs to be changed or
change pictures change images they're
all the same thing so thank you for
watching this tutorial in the next story
we're going to be building probably well
a couple more methods that are going to
be necessary and soon enough we'll have
this animation up and running in no time
but again like I said thank you guys for
watching don't forget subscribe and I'll
see you next time