C++ Allegro 5 Made Easy Tutorial 36 - Loading Tile Maps [Advanced] Video Lecture | Allegro: A Complete Guide - Game Development

hello everybody and welcome to your 36 a
letter 5 tutorial and this is the
financial Tory alone loading maps and
this is going to be the advanced method
on how to do so so let us get started so
this is a CO from the last tutorial so
we learned about vectors and sand and
why not so in this tutorial we're going
to be introducing towels and textures
and stuff but we're going to be learning
an additional way and how to load them
it's always good to load things
externally because well you don't have
to become pollinating so I'm going to be
showing you how to load two different
things from one file externally okay now
if we look at if we look into my project
folder I have two images together sorry
and I named it i named the fondant tiles
right so this is the zeros are going to
represent this towel and the ones are
going to represent this tile over here
okay so uh and now if you watch my leg
room for two tours or a lego HD or
whatever as familiar XNA I had these in
separate files and I loaded them and
separately but when it comes to
programming is always good to have a
towel sheet or sprite sheet because in
loading in one image is better than
loading in two images it's faster it
doesn't require that much from the
hardware it's easier to work with a
slight weight etc etc so I I got them
both into one image so if we go to we
need to open up our map file and what
we're going to do is we're going to have
to identify her so i will name this tile
or towel set and the top so we're going
to be loading it's gonna be tiles PNG
and matt okay so and before what i used
to do was that I used to load each
individual tile and say I just how was
the ground tile or whatever and the next
how was another towel the zeros will
represent the first time the ones
represent a second towel this one we're
in this tutorial only
towel sets we're loading one image and
from these numbers that we specify we're
going to take we're going to crop out
whatever image it is from that file so
so we vote oh so we got our identifies
and we identify it by doing this the
square bracket surrounded by the word
right there okay so what we need to do
is go to our code and we need to need to
create an enum and we can get rid of
this stuff apparel you'll need it so we
have an email I mean um sorry and load
state and I'll have towel set and Matt
and I'll have a state equal to no okay
so uh what we need to do is first we
need to get the get the line so we have
our get line function so if so what we
need to do is you need to say that if
line dots find so if you find this value
in here so towel set so if it locates
this right here not equals STD and no se
D string and position therefore that
means is found its over found this line
then we set state equal to our state is
going to be equal to some tile set and
we see elsif line defined and we find
map oh okay not equals to STD string and
position then state is going to be equal
to map okay so now we're going to have
us uh oh and we have to after we do that
we're just going to put continue
ok so then what the continuing keyword
does is that when it reaches it it will
it's kind of like it will skip the rest
of the program and go right back to the
top of the top of the loop again ok so
it'll skip the rest of the loop and
that's what we want because if we change
if you set the state equal to map and
then we do the map functionality it's
not going to have the contents and needs
to do the Maya functionality only has a
map keyword so you want to continue so
we get the new information so we're
going to do is we're going to do a
switch I'm going to take in the we're
going to take in the state I want to say
case our towel set ok so if it's if the
case is so if the state is equal to
towel set then basically you want to
load in that towel set so are right
above here we'll just make a bitmap
which make it global for now and we'll
just set it to town set so what we're
going to do is we're going to load an
hour we're going to load in the town
side that is specified so we'll say
tileset equals L load bitmap and we'll
load in the line Oh line c string so the
thing the thing about this is that uh
one problem that you can run into is
that if you say have spaces behind or
before I don't know if that will affect
to the loading in oh I'm not going to
get into in that but you can remove
these spaces just like I specify the
last tutorial by saying fine last night
of and find first of two move those
spaces before and after the file name
just to just so there's no errors so
after we do that you know we loaded in
the towel set and I'm going to have a
next case so we want to break that so
we'll have a next case and if the if
it's if the state is equal to map then
we want to load in the map so we already
have our load map function right here so
which have to copy this
I checked the pasted them right in there
and I'll end then the code so after that
we just set break okay so once you do
that so we got our town set loaded and
we got our map loaded okay so now let's
go down to our our draw function in here
ok so our drawings wouldn't be different
without drawing a rectangular brute
drawings it based on the tile sheet
right so uh what we were what we're
going to do is we're going to say i'll
draw bitmap and uh okay what would not
actually we should say draw a bitmap
region sorry so we're drawing the towel
set okay the source excellent source y
is going to be equals to map I the
source X is going to be equal to map IJ
0 times and what's the block size the
block size is 40 i believe ya block size
right so and then for the why it's going
to start at zero the source width is
going to be there both 40 yeah it's a
block size and for the height is going
to be equal to 32 I know the I I said
the block sizes for both x and y but in
this case the images are 40 x 32 so the
height of it is 32 from my image
depending on the height of your image
you can specify it and for the x and y
we're just going to say j x block size
and we'll have I tons of block size and
there's no flags so if we run this
program let's see what we get
gotta wait for it to compile hopefully
there's no errors if there's any errors
and I'll just pause the video and then
all I'll fix it I'll tell you out what I
did wrong okay so there was an error so
let me check what I did wrong okay I
think I found the problem and the
problem is that if we look at our map
file it takes the towels again the loads
it's in but then it takes it says that
we're trying to load in a file name
right here right so what we want to do
is if we go to a program will say we
cook we could do another thing we can
say if a towel set not equals to null or
we could say that if the line dot length
is greater than zero let me do that
either either method should work so if
we run this program right here run it
one last time hopefully it works this
time ooh still doesn't work so let me
pause it again to figure it out okay
yeah I got it so we have two are also
sorry for all the mistakes in this video
but we also have to include the image
and add the image add on to our programs
so where's the ale in it image ad on now
I don't know if this we might still get
an error because we created a bitmap and
stuff like that above here so what I'm
going to do is I'm going to copy this
right here I'm going to cut this and
paste at the bottom of our code right
here and just take the beginning
statement of here and paste it at the
top okay so hopefully it run smoothly
this time okay so there we have it
so we got everything drawn according to
the way it's drawn on a map so these
represent the cereals and these
represent the ones so i hope you enjoyed
this tutorial thanks for watching and
bye