I'm hitting what I assume is a pretty basic misunderstanding of how to draw things using the Rust Piston library. Here is the main function I'm working with, mostly copied from beginner tutorials.
extern crate piston_window;
use piston_window::*;
fn main() {
let dims = (640.0, 480.0);
let mut window: PistonWindow =
WindowSettings::new("Hello, Piston!", (dims.0 as u32, dims.1 as u32))
.exit_on_esc(true)
.build()
.unwrap();
while let Some(e) = window.next() {
match e {
Event::Loop(Loop::Render(_)) => {
window.draw_2d(&e, |c, g| {
clear([1.0; 4], g);
rectangle(
[1.0, 0.0, 0.0, 1.0],
[0.0, 0.0, dims.0, dims.1],
c.transform,
g,
);
});
}
_ => {}
}
}
}
I'm trying to draw a red rectangle the size of the window, but when I run this function, I get a red box drawn on the lower-left corner of the frame, not occupying the whole window as I might expect.
Oddly enough, if I change the dimensions to (480.0, 480.0) so that the window is a square, the box fills up the window like I would expect. I imagine this is simply me misunderstanding how Piston treats coordinates. What exactly am I missing here, and why does it seem like the position (0, 0) is halfway down the window on the left?
