Hands-on Rust: B4.0 changing initialization code to use graphics (page 140)

On page 140 we change the initialization code of the dungeon crawler to be able to use graphics

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As with other code examples before the relevant lines are annotated and explained afterwards. What I’ve noticed (and briefly struggled with) is that the first line also changed from:

let context = BTermBuilder::simple80x50()

to:

let context = BTermBuilder::new()

The change is small and easy to miss while the consequences are quite grave. If one misses the change and leaves the first line as BTermBuilder::simple80x50() the program will crash on startup with the following error:

thread 'main' panicked at 'Failed to load texture: IoError(Os { code: 2, kind: NotFound, message: "No such file or directory" })', /Users/swolf/.cargo/registry/src/github.com-1ecc6299db9ec823/bracket-terminal-0.8.1/src/hal/gl_common/font.rs:41:18
note: run with `RUST_BACKTRACE=1` environment variable to display a backtrace

I suggest to also highlight the change from BTermBuilder::simple80x50() to BTermBuilder::new() with an additional explanation on why this is necessary.

On another note: I’m very much enjoying the book.