Detect diagonals better on controllers

src/controller.rs

@@ -1,4 +1,7 @@
-use std::sync::{Arc, RwLock};
+use std::{
+    collections::HashMap,
+    sync::{Arc, RwLock},
+};
 
 use gilrs::{Event as GamepadEvent, EventType, GamepadId, ev::Code};
 use winit::{
@@ -8,12 +11,13 @@ use winit::{
 
 use crate::{
     emulator::{EmulatorClient, EmulatorCommand, SimId, VBKey},
-    input::{InputMapping, MappingProvider},
+    input::{AxisMapping, InputMapping, MappingProvider},
 };
 
 pub struct Controller {
     pub sim_id: SimId,
     state: VBKey,
+    axis_values: HashMap<(GamepadId, Code), f32>,
     mapping: Arc<RwLock<InputMapping>>,
 }
 
@@ -22,6 +26,7 @@ impl Controller {
         Self {
             sim_id,
             state: VBKey::SGN,
+            axis_values: HashMap::new(),
             mapping: mappings.for_sim(sim_id).clone(),
         }
     }
@@ -45,22 +50,18 @@ impl Controller {
                 (VBKey::empty(), mappings)
             }
             EventType::AxisChanged(_, value, code) => {
-                let (neg, pos) = self.map_axis(&event.id, &code)?;
+                let mapping = self.map_axis(&event.id, &code)?;
-                let mut pressed = VBKey::empty();
+                self.axis_values.insert((event.id, code), value);
-                let mut released = VBKey::empty();
+
-                if value < -0.75 {
+                let pair_value = mapping
-                    pressed = pressed.union(neg);
+                    .pair
-                }
+                    .and_then(|p| self.axis_values.get(&(event.id, p)))
-                if value > 0.75 {
+                    .copied()
-                    pressed = pressed.union(pos);
+                    .unwrap_or_default();
-                }
+                let neg = mapping.neg;
-                if value > -0.65 {
+                let pos = mapping.pos;
-                    released = released.union(neg);
+
-                }
+                axis_presses(value, pair_value, neg, pos)
-                if value < 0.65 {
-                    released = released.union(pos);
-                }
-                (pressed, released)
             }
             _ => {
                 return None;
@@ -87,7 +88,7 @@ impl Controller {
         self.mapping.read().unwrap().map_button(id, code)
     }
 
-    fn map_axis(&self, id: &GamepadId, code: &Code) -> Option<(VBKey, VBKey)> {
+    fn map_axis(&self, id: &GamepadId, code: &Code) -> Option<AxisMapping> {
         self.mapping.read().unwrap().map_axis(id, code)
     }
 }
@@ -126,3 +127,81 @@ impl ControllerManager {
         }
     }
 }
+
+fn axis_presses(value: f32, pair_value: f32, neg: VBKey, pos: VBKey) -> (VBKey, VBKey) {
+    use std::f32::consts::FRAC_PI_3;
+
+    let mut pressed = VBKey::empty();
+    let mut released = VBKey::empty();
+
+    let magnitude = value.hypot(pair_value);
+    let abs_angle = pair_value.atan2(value);
+
+    if magnitude < 0.65 {
+        released = released.union(neg).union(pos);
+    } else if abs_angle <= FRAC_PI_3 {
+        // stick tilted towards positive
+        released = released.union(neg);
+
+        if magnitude >= 0.75 {
+            pressed = pressed.union(pos);
+        }
+    } else if abs_angle >= 2.0 * FRAC_PI_3 {
+        // stick tilted towards negative
+        released = released.union(pos);
+
+        if magnitude >= 0.75 {
+            pressed = pressed.union(neg);
+        }
+    } else {
+        released = released.union(neg).union(pos);
+    }
+
+    (pressed, released)
+}
+
+#[cfg(test)]
+mod tests {
+    use super::{VBKey, axis_presses};
+
+    const NEG: VBKey = VBKey::LL;
+    const POS: VBKey = VBKey::LR;
+
+    const NONE: VBKey = VBKey::empty();
+    const BOTH: VBKey = NEG.union(POS);
+
+    #[test]
+    fn detects_no_input() {
+        let (pressed, released) = axis_presses(0.0, 0.0, NEG, POS);
+        assert_eq!(pressed, NONE);
+        assert_eq!(released, BOTH);
+    }
+
+    #[test]
+    fn detects_pos_input() {
+        let (pressed, released) = axis_presses(1.0, 0.0, NEG, POS);
+        assert_eq!(pressed, POS);
+        assert_eq!(released, NEG);
+    }
+
+    #[test]
+    fn detects_neg_input() {
+        let (pressed, released) = axis_presses(-1.0, 0.0, NEG, POS);
+        assert_eq!(pressed, NEG);
+        assert_eq!(released, POS);
+    }
+
+    #[test]
+    fn respects_dead_zone() {
+        let (pressed, released) = axis_presses(0.70, 0.0, NEG, POS);
+        assert_eq!(pressed, NONE);
+        assert_eq!(released, NEG);
+    }
+
+    #[test]
+    fn handles_diagonals_ok() {
+        let (pressed, released) = axis_presses(0.6, 0.6, NEG, POS);
+        assert_eq!(pressed, POS);
+        assert_eq!(released, NEG);
+    }
+}

src/input.rs

@@ -52,12 +52,28 @@ pub trait Mappings {
     fn use_default_mappings(&mut self);
 }
 
+#[derive(Clone, Copy, Serialize, Deserialize)]
+pub struct AxisMapping {
+    pub neg: VBKey,
+    pub pos: VBKey,
+    pub pair: Option<Code>,
+}
+impl Default for AxisMapping {
+    fn default() -> Self {
+        Self {
+            neg: VBKey::empty(),
+            pos: VBKey::empty(),
+            pair: None,
+        }
+    }
+}
+
 #[derive(Serialize, Deserialize)]
 pub struct GamepadMapping {
     buttons: HashMap<Code, VBKey>,
-    axes: HashMap<Code, (VBKey, VBKey)>,
+    axes: HashMap<Code, AxisMapping>,
     default_buttons: HashMap<Code, VBKey>,
-    default_axes: HashMap<Code, (VBKey, VBKey)>,
+    default_axes: HashMap<Code, AxisMapping>,
 }
 
 impl GamepadMapping {
@@ -78,7 +94,8 @@ impl GamepadMapping {
         let mut default_axes = HashMap::new();
         let mut default_axis = |axis: Axis, neg: VBKey, pos: VBKey| {
             if let Some(code) = gamepad.axis_code(axis) {
-                default_axes.insert(code, (neg, pos));
+                let pair = axis.second_axis().and_then(|a| gamepad.axis_code(a));
+                default_axes.insert(code, AxisMapping { neg, pos, pair });
             }
         };
         default_axis(Axis::LeftStickX, VBKey::LL, VBKey::LR);
@@ -102,19 +119,13 @@ impl GamepadMapping {
     }
 
     pub fn add_axis_neg_mapping(&mut self, key: VBKey, code: Code) {
-        let entry = self
+        let entry = self.axes.entry(code).or_default();
-            .axes
+        entry.neg = entry.neg.union(key);
-            .entry(code)
-            .or_insert((VBKey::empty(), VBKey::empty()));
-        entry.0 = entry.0.union(key);
     }
 
     pub fn add_axis_pos_mapping(&mut self, key: VBKey, code: Code) {
-        let entry = self
+        let entry = self.axes.entry(code).or_default();
-            .axes
+        entry.pos = entry.pos.union(key);
-            .entry(code)
-            .or_insert((VBKey::empty(), VBKey::empty()));
-        entry.1 = entry.1.union(key);
     }
 
     fn save_mappings(&self) -> PersistedGamepadMapping {
@@ -145,11 +156,11 @@ impl GamepadMapping {
 impl Mappings for GamepadMapping {
     fn mapping_names(&self) -> HashMap<VBKey, Vec<String>> {
         let mut results: HashMap<VBKey, Vec<String>> = HashMap::new();
-        for (axis, (left_keys, right_keys)) in &self.axes {
+        for (axis, mapping) in &self.axes {
-            for key in left_keys.iter() {
+            for key in mapping.neg.iter() {
                 results.entry(key).or_default().push(format!("-{axis}"));
             }
-            for key in right_keys.iter() {
+            for key in mapping.pos.iter() {
                 results.entry(key).or_default().push(format!("+{axis}"));
             }
         }
@@ -162,10 +173,10 @@ impl Mappings for GamepadMapping {
     }
 
     fn clear_mappings(&mut self, key: VBKey) {
-        self.axes.retain(|_, (left, right)| {
+        self.axes.retain(|_, mapping| {
-            *left = left.difference(key);
+            mapping.neg = mapping.neg.difference(key);
-            *right = right.difference(key);
+            mapping.pos = mapping.pos.difference(key);
-            !(left.is_empty() && right.is_empty())
+            !(mapping.neg.is_empty() && mapping.pos.is_empty())
         });
         self.buttons.retain(|_, keys| {
             *keys = keys.difference(key);
@@ -200,7 +211,7 @@ impl InputMapping {
         mappings.buttons.get(code).copied()
     }
 
-    pub fn map_axis(&self, id: &GamepadId, code: &Code) -> Option<(VBKey, VBKey)> {
+    pub fn map_axis(&self, id: &GamepadId, code: &Code) -> Option<AxisMapping> {
         let mappings = self.gamepads.get(id)?.read().unwrap();
         mappings.axes.get(code).copied()
     }
@@ -459,9 +470,9 @@ struct PersistedKeyboardMapping {
 #[derive(Serialize, Deserialize)]
 struct PersistedGamepadMapping {
     buttons: Vec<(Code, VBKey)>,
-    axes: Vec<(Code, (VBKey, VBKey))>,
+    axes: Vec<(Code, AxisMapping)>,
     default_buttons: Vec<(Code, VBKey)>,
-    default_axes: Vec<(Code, (VBKey, VBKey))>,
+    default_axes: Vec<(Code, AxisMapping)>,
 }
 
 #[derive(Clone, Copy, Serialize, Deserialize, PartialEq, Eq, Hash)]