0.1.0-0-pre.11-fix.3

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

@@ -1,5 +1,5 @@
 // file: crates/engines/engine-v1-sdl/src/runtime.rs
-// version: 8
+// version: 9
 
 /// Minimal SDL3 runtime used by Desktop and Android POC runners.
 pub struct SdlRuntime {
@@ -39,6 +39,7 @@ impl SdlRuntime {
             std::result::Result::Err(error) => return std::result::Result::Err(error.to_string()),
         };
         let mut runner = engine_v1_common::FixedStepRunner::new(self.frame_duration);
+        let mut gesture_start: Option<engine_v1_common::PointerState> = None;
         let mut pointer = engine_v1_common::PointerState::inactive();
         tracing::info!(title = %self.title, width = self.width, height = self.height, "SDL3 runtime started");
         'running: loop {
@@ -61,11 +62,14 @@ impl SdlRuntime {
                     },
                     sdl3::event::Event::MouseButtonDown { mouse_btn: sdl3::mouse::MouseButton::Left, x, y, .. } => {
                         pointer = normalize_mouse_pointer(&canvas, true, x, y);
+                        gesture_start = Some(pointer);
                         input = input.with_pointer(pointer).with_action(engine_v1_common::GameAction::Primary, true);
-                        input = apply_pointer_direction(input, pointer);
                     },
                     sdl3::event::Event::MouseButtonUp { mouse_btn: sdl3::mouse::MouseButton::Left, x, y, .. } => {
-                        pointer = normalize_mouse_pointer(&canvas, false, x, y);
+                        let released = normalize_mouse_pointer(&canvas, false, x, y);
+                        input = apply_swipe_direction(input, gesture_start, released);
+                        gesture_start = None;
+                        pointer = released;
                         input = input.with_pointer(pointer);
                     },
                     sdl3::event::Event::MouseMotion { x, y, .. } if pointer.active() => {
@@ -74,14 +78,22 @@ impl SdlRuntime {
                     },
                     sdl3::event::Event::FingerDown { x, y, .. } => {
                         pointer = engine_v1_common::PointerState::normalized(true, x, y);
+                        gesture_start = Some(pointer);
                         input = input.with_pointer(pointer).with_action(engine_v1_common::GameAction::Primary, true);
-                        input = apply_pointer_direction(input, pointer);
                     },
                     sdl3::event::Event::FingerMotion { x, y, .. } => {
                         pointer = engine_v1_common::PointerState::normalized(true, x, y);
                         input = input.with_pointer(pointer);
                     },
-                    sdl3::event::Event::FingerUp { x, y, .. } | sdl3::event::Event::FingerCanceled { x, y, .. } => {
+                    sdl3::event::Event::FingerUp { x, y, .. } => {
+                        let released = engine_v1_common::PointerState::normalized(false, x, y);
+                        input = apply_swipe_direction(input, gesture_start, released);
+                        gesture_start = None;
+                        pointer = released;
+                        input = input.with_pointer(pointer);
+                    },
+                    sdl3::event::Event::FingerCanceled { x, y, .. } => {
+                        gesture_start = None;
                         pointer = engine_v1_common::PointerState::normalized(false, x, y);
                         input = input.with_pointer(pointer);
                     },
@@ -134,9 +146,23 @@ fn render_scene(canvas: &mut sdl3::render::WindowCanvas, scene: engine_v1_common
     return std::result::Result::Ok(());
 }
 
-fn apply_pointer_direction(mut input: engine_v1_common::InputState, pointer: engine_v1_common::PointerState) -> engine_v1_common::InputState {
-    let horizontal = pointer.x() - 0.5;
-    let vertical = pointer.y() - 0.5;
+const SWIPE_DIRECTION_THRESHOLD: f32 = 0.04;
+
+fn apply_swipe_direction(
+    mut input: engine_v1_common::InputState,
+    start: Option<engine_v1_common::PointerState>,
+    end: engine_v1_common::PointerState,
+) -> engine_v1_common::InputState {
+    let start = match start {
+        Some(value) => value,
+        None => return input,
+    };
+    let horizontal = end.x() - start.x();
+    let vertical = end.y() - start.y();
+    let dominant = horizontal.abs().max(vertical.abs());
+    if dominant < SWIPE_DIRECTION_THRESHOLD {
+        return input;
+    }
     if horizontal.abs() >= vertical.abs() {
         if horizontal < 0.0 {
             input = input.with_action(engine_v1_common::GameAction::Left, true);
@@ -150,3 +176,7 @@ fn apply_pointer_direction(mut input: engine_v1_common::InputState, pointer: eng
     }
     return input;
 }
+
+#[cfg(test)]
+#[path = "../unit_tests/swipe.rs"]
+mod swipe_tests;

crates/engines/engine-v1-sdl/unit_tests/swipe.rs

@@ -0,0 +1,27 @@
+// file: crates/engines/engine-v1-sdl/unit_tests/swipe.rs
+// version: 1
+
+fn pointer(x: f32, y: f32) -> engine_v1_common::PointerState {
+    return engine_v1_common::PointerState::normalized(true, x, y);
+}
+
+#[test]
+fn short_gesture_does_not_emit_direction() {
+    let input = super::apply_swipe_direction(engine_v1_common::InputState::none(), Some(pointer(0.5, 0.5)), pointer(0.52, 0.51));
+    assert!(!input.is_active(engine_v1_common::GameAction::Left));
+    assert!(!input.is_active(engine_v1_common::GameAction::Right));
+    assert!(!input.is_active(engine_v1_common::GameAction::Up));
+    assert!(!input.is_active(engine_v1_common::GameAction::Down));
+}
+
+#[test]
+fn horizontal_swipe_uses_dominant_axis() {
+    let input = super::apply_swipe_direction(engine_v1_common::InputState::none(), Some(pointer(0.7, 0.5)), pointer(0.2, 0.55));
+    assert!(input.is_active(engine_v1_common::GameAction::Left));
+}
+
+#[test]
+fn vertical_swipe_uses_dominant_axis() {
+    let input = super::apply_swipe_direction(engine_v1_common::InputState::none(), Some(pointer(0.5, 0.8)), pointer(0.55, 0.2));
+    assert!(input.is_active(engine_v1_common::GameAction::Up));
+}