0.1.0-0-pre.5

crates/engines/engine-v1-sdl/src/runtime.rs

@@ -1,14 +1,84 @@
 // file: crates/engines/engine-v1-sdl/src/runtime.rs
 // version: 1
 
-/// Marker representing the future SDL3 runtime boundary for engine V1.
-#[derive(Clone, Copy, Debug, Default, Eq, PartialEq)]
-pub struct SdlRuntimeBoundary;
+use sdl3::event::Event;
+use sdl3::keyboard::Keycode;
+use sdl3::pixels::Color;
 
-impl SdlRuntimeBoundary {
-    /// Returns the engine generation served by this boundary.
+use engine_v1_common::{Action, EngineGame, FixedStepRunner, InputState};
+
+/// Minimal SDL3 runtime used by Desktop POC runners.
+pub struct SdlRuntime {
+    title: String,
+    width: u32,
+    height: u32,
+    frame_duration_ms: u64,
+}
+
+impl SdlRuntime {
+    /// Creates a minimal SDL3 runtime configuration.
     #[must_use]
-    pub const fn engine_generation() -> u16 {
-        return 1;
+    pub fn new(title: impl Into<String>, width: u32, height: u32, frame_duration_ms: u64) -> Self {
+        return Self {
+            title: title.into(),
+            width,
+            height,
+            frame_duration_ms,
+        };
+    }
+
+    /// Runs a game until the user closes the window or presses Escape.
+    pub fn run<G: EngineGame>(&self, game: &mut G) -> Result<(), String> {
+        let sdl = sdl3::init().map_err(|error| error.to_string())?;
+        let video = sdl.video().map_err(|error| error.to_string())?;
+        let window = video
+            .window(&self.title, self.width, self.height)
+            .position_centered()
+            .build()
+            .map_err(|error| error.to_string())?;
+        let mut canvas = window.into_canvas();
+        let mut events = sdl.event_pump().map_err(|error| error.to_string())?;
+        let mut runner = FixedStepRunner::new(self.frame_duration_ms);
+
+        tracing::info!(
+            title = %self.title,
+            width = self.width,
+            height = self.height,
+            "SDL3 runtime started"
+        );
+
+        'running: loop {
+            let mut input = InputState::default();
+
+            for event in events.poll_iter() {
+                match event {
+                    Event::Quit { .. } => {
+                        break 'running;
+                    }
+                    Event::KeyDown {
+                        keycode: Some(Keycode::Escape),
+                        ..
+                    } => {
+                        break 'running;
+                    }
+                    Event::KeyDown {
+                        keycode: Some(Keycode::Space),
+                        ..
+                    } => {
+                        input.set(Action::Primary, true);
+                    }
+                    _ => {}
+                }
+            }
+
+            runner.tick(game, &input);
+
+            canvas.set_draw_color(Color::RGB(18, 18, 24));
+            canvas.clear();
+            canvas.present();
+        }
+
+        tracing::info!("SDL3 runtime stopped");
+        return Ok(());
     }
 }