charco

charco

Hands-on Rust: flappy_player y position. (Page 59)

In the flappy bird example in the book, the example code uses i32 as the type for the player’s y position. This has a possible unintended effect in the gravity_and_move function: The player position will not be modified until the speed is greater than 1.0. This is because the line:

self.y += self.velocity as i32;

will convert the velocity to an i32 (rounding towards 0) before updating the player’s y position.

This has a big effect in playability, as every time you go press the spacebar, your velocity changes to -2.0, and then when it gets from -1 to 1, your y position will not change at all.

A better solution would be to set the y position as an f32, and cast it to int only when you want to draw it on the terminal.

Where Next?

Popular Pragmatic Bookshelf topics Top

telemachus
Python Testing With Pytest - Chapter 2, warnings for “unregistered custom marks” While running the smoke tests in Chapter 2, I get these...
New
jeffmcompsci
Title: Design and Build Great Web APIs - typo “https://company-atk.herokuapp.com/2258ie4t68jv” (page 19, third bullet in URL list) Typo:...
New
simonpeter
When I try the command to create a pair of migration files I get an error. user=> (create-migration "guestbook") Execution error (Ill...
New
jdufour
Hello! On page xix of the preface, it says there is a community forum "… for help if your’re stuck on one of the exercises in this book… ...
New
JohnS
I can’t setup the Rails source code. This happens in a working directory containing multiple (postgres) Rails apps. With: ruby-3.0.0 s...
New
jskubick
I think I might have found a problem involving SwitchCompat, thumbTint, and trackTint. As entered, the SwitchCompat changes color to hol...
New
jgchristopher
“The ProductLive.Index template calls a helper function, live_component/3, that in turn calls on the modal component. ” Excerpt From: Br...
New
brunogirin
When installing Cards as an editable package, I get the following error: ERROR: File “setup.py” not found. Directory cannot be installe...
New
tkhobbes
After some hassle, I was able to finally run bin/setup, now I have started the rails server but I get this error message right when I vis...
New
bjnord
Hello @herbert ! Trying to get the very first “Hello, Bracket Terminal!" example to run (p. 53). I develop on an Amazon EC2 instance runn...
New

Other popular topics Top

Devtalk
Hello Devtalk World! Please let us know a little about who you are and where you’re from :nerd_face:
New
PragmaticBookshelf
Brace yourself for a fun challenge: build a photorealistic 3D renderer from scratch! In just a couple of weeks, build a ray tracer that r...
New
PragmaticBookshelf
Learn from the award-winning programming series that inspired the Elixir language, and go on a step-by-step journey through the most impo...
New
PragmaticBookshelf
Write Elixir tests that you can be proud of. Dive into Elixir’s test philosophy and gain mastery over the terminology and concepts that u...
New
Exadra37
Please tell us what is your preferred monitor setup for programming(not gaming) and why you have chosen it. Does your monitor have eye p...
New
PragmaticBookshelf
Build highly interactive applications without ever leaving Elixir, the way the experts do. Let LiveView take care of performance, scalabi...
New
sir.laksmana_wenk
I’m able to do the “artistic” part of game-development; character designing/modeling, music, environment modeling, etc. However, I don’t...
New
PragmaticBookshelf
Fight complexity and reclaim the original spirit of agility by learning to simplify how you develop software. The result: a more humane a...
New
PragmaticBookshelf
A concise guide to MySQL 9 database administration, covering fundamental concepts, techniques, and best practices. Neil Smyth MySQL...
New
PragmaticBookshelf
Use advanced functional programming principles, practical Domain-Driven Design techniques, and production-ready Elixir code to build scal...
New

Sub Categories: