fix rendering: clear boot logo on first update, stack text vertically

crates/client-esp32/src/tasks/render.rs

@@ -2,36 +2,55 @@ use std::sync::mpsc;
 use client_domain::{BoundingBox, DisplayPort};
 use client_application::ClientApp;
 use protocol::ServerMessage;
-use crate::config::RENDER_POLL_INTERVAL;
+use crate::config::{RENDER_POLL_INTERVAL, SCREEN};
 use crate::adapters::display::Esp32DisplayAdapter;
 use log::*;
 
+const LINE_HEIGHT: u16 = 12;
+const TEXT_PADDING: u16 = 4;
+
 pub fn run(
     screen: BoundingBox,
     mut display: Esp32DisplayAdapter,
     rx: mpsc::Receiver<ServerMessage>,
 ) {
     let mut app = ClientApp::new(screen);
+    let mut first_update = true;
     info!("Render loop started");
 
     loop {
         match rx.recv_timeout(RENDER_POLL_INTERVAL) {
             Ok(msg) => {
                 let repaints = app.handle_message(msg);
+
+                if !repaints.is_empty() && first_update {
+                    display.fill_background(SCREEN).unwrap();
+                    first_update = false;
+                }
+
                 for cmd in &repaints {
                     display.clear_region(cmd.bounds).unwrap();
 
+                    let mut y_offset = TEXT_PADDING;
                     for kv in &cmd.state.data {
                         if let protocol::WireValue::String(s) = &kv.value {
+                            let text_bounds = BoundingBox::new(
+                                cmd.bounds.x + TEXT_PADDING,
+                                cmd.bounds.y + y_offset,
+                                cmd.bounds.width.saturating_sub(TEXT_PADDING * 2),
+                                LINE_HEIGHT,
+                            );
                             display.draw_text(
                                 &format!("{}: {s}", kv.key),
-                                cmd.bounds.x,
+                                text_bounds.x,
-                                cmd.bounds.y,
+                                text_bounds.y,
-                                cmd.bounds,
+                                text_bounds,
                             ).unwrap();
+                            y_offset += LINE_HEIGHT + 2;
                         }
                     }
                 }
+
                 if !repaints.is_empty() {
                     display.flush().unwrap();
                 }