alex/agb
1
0
Fork 0
mirror of https://github.com/italicsjenga/agb.git synced 2024-12-23 16:21:33 +11:00
Code Issues Packages Projects Releases Wiki Activity

Update the book and the template

Browse source
This commit is contained in:
Gwilym Kuiper 2022-01-16 21:46:53 +00:00
parent 9feab2b689
commit f3e3782699
2 changed files with 7 additions and 10 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

10
book/src/pong/02_the_gba_struct.md
View file

@ -1,15 +1,15 @@
# The Gba struct # The Gba struct
In this section, we'll cover the importance of the Gba struct and how to create it. In this section, we'll cover the importance of the Gba struct and how it gets created for you.
# The importance of the Gba struct # The importance of the Gba struct
Almost all interaction with the Game Boy Advance's hardware goes through the [Gba singleton struct](https://docs.rs/agb/latest/agb/struct.Gba.html). Almost all interaction with the Game Boy Advance's hardware goes through the [Gba singleton struct](https://docs.rs/agb/latest/agb/struct.Gba.html).
Your games using `agb` will typically create this in the `main` function and then handle the abstractions in there. You should not create the Gba struct yourself, instead having it be passed into your main function.
The Gba struct is used to take advantage of rust's borrow checker, and lean on it to ensure that access to the Game Boy Advance hardware is done 'sensibly'. The Gba struct is used to take advantage of rust's borrow checker, and lean on it to ensure that access to the Game Boy Advance hardware is done 'sensibly'.
You won't have to worry about 2 bits of your code modifying data in the wrong way! You won't have to worry about 2 bits of your code modifying data in the wrong way!
This struct is a 'singleton', so you cannot create 2 instances of it at once. This struct is a 'singleton', so you cannot create another instance of it.
Attempting to do so will result in a panic which by default crashes the game. Attempting to do so will result in a panic which by default crashes the game.
# How all agb games start # How all agb games start
@ -21,8 +21,6 @@ Replace the content of the `main` function with the following:
# #![no_main] # #![no_main]
# #[agb::entry] # #[agb::entry]
# fn main() -> ! { # fn main() -> ! {
let mut gba = agb::Gba::new();
loop {} // infinite loop for now loop {} // infinite loop for now
# } # }
``` ```
@ -36,6 +34,6 @@ Although there isn't much to see at the moment (just a black screen), you can st
# What we did # What we did
This was a very simple but incredibly important part of any game using `agb`. This was a very simple but incredibly important part of any game using `agb`.
All interactions with the hardware are gated via the Gba struct, so it must be created at the start of your `main` function and never again. All interactions with the hardware are gated via the Gba struct, which you never create yourself.
You are now ready to learn about display modes and how to start getting things onto the screen! You are now ready to learn about display modes and how to start getting things onto the screen!

7
template/src/main.rs
View file

@ -12,12 +12,11 @@
use agb::{display, syscall}; use agb::{display, syscall};
// The main function must take 0 arguments and never return. The agb::entry decorator // The main function must take 1 arguments and never return. The agb::entry decorator
// ensures that everything is in order. `agb` will call this after setting up the stack // ensures that everything is in order. `agb` will call this after setting up the stack
// and interrupt handlers correctly. // and interrupt handlers correctly. It will also handle creating the `Gba` struct for you.
#[agb::entry] #[agb::entry]
fn main() -> ! { fn main(mut gba: agb::Gba) -> ! {
let mut gba = agb::Gba::new();
let mut bitmap = gba.display.video.bitmap3(); let mut bitmap = gba.display.video.bitmap3();
for x in 0..display::WIDTH { for x in 0..display::WIDTH {