Add code to render text, refactor render into OOPish

src/gtfs/mod.rs

@@ -7,7 +7,7 @@ use std::{
 };
 use crate::gtfs::{loader::load_gtfs, structs::{Arrival, Gtfs, Preferences}};
 
-pub fn _get_next_stops(_gtfs: &Gtfs) -> Vec<Arrival> {
+pub fn _get_next_stops(_gtfs: &Gtfs) -> Vec<Arrival<'_>> {
     let arrivals = Vec::<Arrival>::new();
 
     return arrivals;

src/main.rs

@@ -1,6 +1,8 @@
 mod gtfs;
 mod renderer;
-use std::{collections::HashSet};
+use std::{collections::HashSet, thread, time::Duration};
+
+use crate::renderer::Screen;
 
 
 const SRC_FILE: &str = "/home/nahuel/Downloads/GTFS_Realtime.zip";
@@ -13,16 +15,22 @@ fn main() {
     };
 
     let screen_prefs = renderer::structs::Prefs {
-        font_path: String::from("todo!()"),
+        font_path: String::from("resources/jd-lcd-rounded.ttf/jd-lcd-rounded.ttf"),
         screen_width: 1920,
         screen_height: 720,
     };
 
     // Init GTFS static info
     println!("Loading GTFS data...");
-    let _gtfs = gtfs::load(SRC_FILE, &gtfs_prefs);
+    //let _gtfs = gtfs::load(SRC_FILE, &gtfs_prefs);
 
     // Init screen
-    let _screen = renderer::init(&screen_prefs);
+    println!("Initializing screen...");
+    let mut screen = Screen::init(&screen_prefs);
+    println!("Startup done.");
+
+    screen.print(0, "foo!");
+
+    thread::sleep(Duration::new(10, 0));
 
 }

src/renderer/mod.rs

@@ -1,12 +1,36 @@
 
 pub mod structs;
-use sdl3::{pixels::Color};
-use structs::{Prefs, Screen};
 
-/// Initialize video, allocate buffers and load fonts
-/// Based on https://github.com/vhspace/sdl3-rs/blob/master/examples/ttf-demo.rs
+use sdl3::{pixels::Color, rect::Rect, render::Canvas, sys::metadata::render, ttf::Font, video::Window};
+use structs::{Prefs};
 
-pub fn init(prefs: &Prefs) -> &mut structs::Screen {
+pub struct Screen<'a> {
+    canvas: Box<Canvas<Window>>,
+    font: Box<Font<'a>>
+}
+
+impl Screen<'_> {
+
+    pub fn print(&mut self, line: u32, text: &str) {
+        let rendered_text = self.font.render(text).solid(Color::RED).unwrap();
+        let texture_creator = self.canvas.texture_creator();
+        let texture = rendered_text.as_texture(&texture_creator).unwrap();
+        let _ = self.canvas.copy(&texture, 
+            Rect::new(0, 0, rendered_text.width(), rendered_text.height()), 
+            Rect::new(0, (line * rendered_text.height()).try_into().unwrap(), rendered_text.width(), rendered_text.height()));
+        self.canvas.present();
+    }
+
+
+    pub fn clear(&mut self) {
+        self.canvas.set_draw_color(Color::BLACK);
+        self.canvas.clear();
+        self.canvas.present();
+    }
+
+    /// Initialize video, allocate buffers and load fonts
+    /// Based on https://github.com/vhspace/sdl3-rs/blob/master/examples/ttf-demo.rs
+    pub fn init(prefs: &Prefs) -> Screen {
         // Initialize the screen   
         let sdl_context = sdl3::init().unwrap();
         let video_subsys = sdl_context.video().unwrap();
@@ -20,17 +44,14 @@ pub fn init(prefs: &Prefs) -> &mut structs::Screen {
 
         // Load font
         let ttf_context = sdl3::ttf::init().unwrap();
-    let mut font = ttf_context.load_font(&prefs.font_path, 128.0).unwrap();
+        let font = ttf_context.load_font(&prefs.font_path, 128.0).unwrap();
 
-    // Clear screen
-    let mut canvas = window.into_canvas();
-    canvas.set_draw_color(Color::BLACK);
-    canvas.clear();
-    canvas.present();
-
-    let screen = Screen { 
-        canvas:  &canvas, 
-        font: &font,
+        let mut screen: Screen = Screen {
+            canvas:  Box::new(window.into_canvas()), 
+            font: Box::new(font),
         };
-    return &mut &screen;
+
+        screen.clear();
+        return screen;
+    }
 }

src/renderer/structs.rs

@@ -1,13 +1,7 @@
 use sdl3::{render::Canvas, ttf::Font, video::Window};
 
-
 pub struct Prefs {
     pub font_path: String,
     pub screen_width: u32,
     pub screen_height: u32,
 }
-
-pub struct Screen<'a> {
-    pub canvas: &'a Canvas<Window>,
-    pub font: &'a Font<'a>,
-}