Checkpoint

Cross.toml

@@ -0,0 +1,8 @@
+[build]
+default-target = "aarch64-unknown-linux-gnu"   # use this target if none is explicitly provided
+pre-build = [                                  # additional commands to run prior to building the package
+    "dpkg --add-architecture $CROSS_DEB_ARCH", 
+    "apt update",
+    "apt --assume-yes install apt-utils:$CROSS_DEB_ARCH",
+    "apt --assume-yes install libsdl3-dev:$CROSS_DEB_ARCH"
+]                 

src/gtfs/mod.rs

@@ -15,7 +15,7 @@ use crate::gtfs::{loader::load_gtfs, structs::{Arrival, Gtfs, Preferences}};
 
 impl Gtfs {
 
-    pub fn get_next_arrivals_for(&self, target_datetime: &DateTime<Local>) -> Box<Vec<Arrival<'_>>> {
+    pub fn get_next_arrivals_for(&self, target_datetime: &DateTime<Local>) -> Vec<Arrival<'_>> {
         let naive_target = target_datetime.naive_local();
         let target_date = naive_target.date();
         
@@ -80,7 +80,7 @@ impl Gtfs {
         }
         debug!("Found {} arrivals", arrivals.len());
 
-        return Box::from(arrivals);
+        return arrivals;
     }
         
 

src/main.rs

@@ -1,10 +1,10 @@
 mod gtfs;
 mod renderer;
-use std::{collections::HashSet, ops::Add, process, thread::Builder, time::SystemTime};
+use std::{collections::{HashSet, btree_map::Entry}, ops::Add, process, thread::Builder, time::SystemTime};
 use chrono::{DateTime, Duration, Local, NaiveTime};
 use log::{Metadata, Record, debug, error, info};
 use sdl3::event::Event;
-use crate::{gtfs::structs::{Arrival, Gtfs}, renderer::structs::Screen};
+use crate::{gtfs::structs::{Arrival, Gtfs}, renderer::structs::{DisplayData, DisplayEntry, Screen}};
 
 const SRC_FILE: &str = "/home/nahuel/Downloads/GTFS_Realtime.zip";
 const NUM_ARRIVALS: usize = 4;
@@ -15,10 +15,10 @@ struct RefreshDataEvent {
 }
 
 
-fn refresh_schedule(gtfs: &Gtfs) -> Box<Vec<Arrival<'_>>>  {
+fn refresh_schedule<'a>(gtfs: &'a Gtfs, screen: &'a Screen<'a>) -> Vec<Arrival<'a>>  {
     let current_timestamp = SystemTime::now();
     let datetime: DateTime<Local> = current_timestamp.clone().into(); 
-    let mut next_arrivals: Box<Vec<Arrival<'_>>> = gtfs.get_next_arrivals_for(&datetime);
+    let mut next_arrivals: Vec<Arrival<'_>> = gtfs.get_next_arrivals_for(&datetime);
 
     if next_arrivals.len() < NUM_ARRIVALS {
         // If we don't have enough entries today, look for arrivals tomorrow.
@@ -29,6 +29,21 @@ fn refresh_schedule(gtfs: &Gtfs) -> Box<Vec<Arrival<'_>>>  {
     }
 
     next_arrivals.sort();
+
+    // Create the DisplayData structure to render the information to screen
+    let current_time =  Local::now().time();
+    let display_data: DisplayData = DisplayData {
+        lines: Vec::<DisplayEntry<'_>>::from(next_arrivals.iter().map(|arrival| {
+            DisplayEntry {
+                destination: &String::from("Foo"),
+                route: &arrival.route.short_name.or(arrival.route.long_name).unwrap(),
+                due_in: (arrival.departure_time - current_time).num_minutes().try_into().unwrap()
+            }
+        }).collect()),
+        status: None
+    };
+
+    screen.update_information(&display_data);
     return next_arrivals;
 }
 
@@ -112,7 +127,7 @@ fn main() {
                 let refresh_data = event.as_user_event_type::<RefreshDataEvent>();
                 if refresh_data.is_some() {
                     debug!("Received user event: {:#?}", refresh_data.unwrap());
-                    let _data: Box<Vec<Arrival<'_>>> = refresh_schedule(&gtfs);
+                    let _data: Vec<Arrival<'_>> = refresh_schedule(&gtfs, &screen);
                     debug!("-------------------------------- Refresh done.");
                 }
             }

src/renderer/mod.rs

@@ -1,32 +1,94 @@
 
 pub mod structs;
+use std::cmp::min;
 
 use sdl3::{Sdl, pixels::Color, rect::Rect};
-use structs::{Prefs};
+use structs::{Prefs, DisplayData};
 
 use crate::renderer::structs::Screen;
 
+const LINE_COUNT: i32 = 6;
+const COLOR_LCD_AMBER   : Color = Color::RGB(0xf4, 0xcb, 0x60);
+const COLOR_LCD_GREEN   : Color = Color::RGB(0xb3, 0xff, 0x00);
+const COLOR_LCD_RED     : Color = Color::RGB(0xff, 0x3a, 0x4a);
+
+//const COLOR_BACKGROUND = pygame.Color(0, 0, 0)
+const UPDATE_INTERVAL_SECONDS: u32 = 62;
+const TEXT_SIZE: u32 = 160;  // Size of the font in pixels
+
+// Offsets of each part within a line
+const XOFFSET_ROUTE: u32 = 24;
+const XOFFSET_DESTINATION: u32 = 300;
+const XOFFSEET_TIME_LEFT: u32 = 1606;
+const INTER_LINE_SPACE: i32 = -15; 
+
+
 impl Screen<'_> {
 
     pub fn get_context(&self) -> &Sdl {
         return &self.context;
     }
 
+    fn color_for(&self, due_in: i32) -> Color {
+        if due_in > 15 { return COLOR_LCD_GREEN };
+        if due_in > 10 { return COLOR_LCD_AMBER };
+        return  COLOR_LCD_RED;
+    }
+
+
+    pub fn update_information(&mut self, display_data: &DisplayData) {
+        self.do_clear();
+        let num_arrivals: i32 = min(if display_data.status.is_some() {LINE_COUNT - 1} else {LINE_COUNT}, display_data.lines.len().try_into().unwrap());
+        for line in 0..num_arrivals {
+            // Compose a line of text with all the information 
+            let entry = display_data.lines.get(line as usize).unwrap();
+            let line: u32 = line.try_into().unwrap();
+            let due_in_mins = (entry.due_in / 60) as i32;
+            let arrival_color: Color = self.color_for(due_in_mins);
+
+            self.do_print_at(line, entry.route, XOFFSET_ROUTE);
+            self.do_print_at(line, entry.destination, XOFFSET_DESTINATION);
+            self.do_print_at(line, &due_in_mins.to_string(), XOFFSEET_TIME_LEFT);
+        };
+
+        if display_data.status.is_none() {
+            self.do_print_at(5, display_data.status.as_ref().unwrap(), 0);
+        }
+        self.do_update();
+    }
+
+
     pub fn print(&mut self, line: u32, text: &str) {
+        self.do_print_at(line, text, 0);
+        self.do_update();
+    }
+
+
+    fn do_print_at(&mut self, line: u32, text: &str, left: u32) -> u32 {
         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, 
+        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()));
+            Rect::new(left.try_into().unwrap(), (line * rendered_text.height()).try_into().unwrap(), rendered_text.width(), rendered_text.height()));
-        self.canvas.present();
+        return left + rendered_text.width();
     }
 
 
     pub fn clear(&mut self) {
+        self.do_clear();
+        self.do_update();
+    }
+
+
+    fn do_update (&mut self) {
+        self.canvas.present();
+    }
+
+
+    fn do_clear(&mut self) {
         self.canvas.set_draw_color(Color::BLACK);
         self.canvas.clear();
-        self.canvas.present();
     }
 
     /// Initialize video, allocate buffers and load fonts

src/renderer/structs.rs

@@ -12,3 +12,15 @@ pub struct Prefs {
     pub screen_width: u32,
     pub screen_height: u32,
 }
+
+
+pub struct DisplayEntry<'a> {
+    pub route: &'a String,
+    pub destination: &'a String,
+    pub due_in: i32,
+}
+
+pub struct DisplayData<'a> {
+    pub lines: Vec<DisplayEntry<'a>>,
+    pub status: Option<String>
+}