feat(input): Allow movement / menu nav with dpad and joystick (#991)

This adds `movement_alt` control bindings that default to dpad on
gamepad and None on keyboard mappings.

This allows the dpad or joystick to be used to move player and navigate
menu. We may not want this if we choose to use dpad for other stuff
later, but for now I think this is nice as it avoids player having to
remap gamepad controls to use dpad. Menu navigation on joystick is rough
as have to flick the joystick repeatedly, dpad is a better experience
for me / this came up in feedback too.

Added a helper func to merge both the joystick and dpad input - the
`movement` binding (joystick) is preferred, but if no input it then
takes the `movement_alt` (dpad).

Had a rough time testing this as can't get xbox pro controller 2 to work
(probably macOS issue as it's got bad driver support), or gilrs issue.
And my PS5 controller crashes (is a gilrs issue) lol. but I tested on
steamdeck and this seems to work as intended.

@zicklag @erlend-sh let me know if any concerns with this

assets/game.yaml

@@ -44,6 +44,11 @@ default_settings:
         left: !AxisNegative LeftStickX
         down: !AxisNegative LeftStickY
         right: !AxisPositive LeftStickX
+      movement_alt:
+        up: !Button DPadUp
+        left: !Button DPadLeft
+        down: !Button DPadDown
+        right: !Button DPadRight
       jump: !Button South
       grab: !Button East
       shoot: !Button West

assets/locales/en-US/controls.ftl

@@ -2,6 +2,10 @@ move-up = Move Up
 move-down = Move Down
 move-left = Move Left
 move-right = Move Right
+move-up-alt = Move Up Alt
+move-down-alt = Move Down Alt
+move-left-alt = Move Left Alt
+move-right-alt = Move Right Alt
 jump = Jump
 grab-drop = Grab / Drop
 shoot = Shoot

src/input.rs

@@ -367,16 +367,42 @@ impl<'a>
                 }
             }
 
-            if let Some(left) = get_input_value(&mapping.movement.left, source) {
+            // helper for merging two inputs (like dpad + joystick for example) allowing multiple bindings
+            // for same control
+            let merge_inputs = |input1: &InputKind, input2: &InputKind| -> Option<f32> {
+                let mut out: Option<f32> = None;
+                if let Some(value1) = get_input_value(input1, source) {
+                    out = Some(value1.abs());
+                }
+                if let Some(value2) = get_input_value(input2, source) {
+                    match out {
+                        Some(prev) if prev == 0.0 => {
+                            // If first input is 0.0, override with second input
+                            out = Some(value2.abs());
+                        }
+                        None => {
+                            // No input from first, use second
+                            out = Some(value2.abs());
+                        }
+                        // If first input is non-zero input, use it and ignore second.
+                        Some(_) => {}
+                    }
+                }
+
+                out
+            };
+
+            if let Some(left) = merge_inputs(&mapping.movement.left, &mapping.movement_alt.left) {
                 control.left = left.abs();
             }
-            if let Some(right) = get_input_value(&mapping.movement.right, source) {
+            if let Some(right) = merge_inputs(&mapping.movement.right, &mapping.movement_alt.right)
+            {
                 control.right = right.abs();
             }
-            if let Some(up) = get_input_value(&mapping.movement.up, source) {
+            if let Some(up) = merge_inputs(&mapping.movement.up, &mapping.movement_alt.up) {
                 control.up = up.abs();
             }
-            if let Some(down) = get_input_value(&mapping.movement.down, source) {
+            if let Some(down) = merge_inputs(&mapping.movement.down, &mapping.movement_alt.down) {
                 control.down = down.abs();
             }
         };

src/settings.rs

@@ -83,6 +83,7 @@ impl PlayerControlMapping {
 #[repr(C)]
 pub struct PlayerControlSetting {
     pub movement: VirtualDPad,
+    pub movement_alt: VirtualDPad,
     pub pause: InputKind,
     pub jump: InputKind,
     pub grab: InputKind,

src/ui/main_menu/settings/controls.rs

@@ -71,6 +71,38 @@ pub(super) fn widget(
                 &mut mapping.gamepad.movement.right,
             ],
         ),
+        (
+            localization.get("move-up-alt"),
+            [
+                &mut mapping.keyboard1.movement_alt.up,
+                &mut mapping.keyboard2.movement_alt.up,
+                &mut mapping.gamepad.movement_alt.up,
+            ],
+        ),
+        (
+            localization.get("move-down-alt"),
+            [
+                &mut mapping.keyboard1.movement_alt.down,
+                &mut mapping.keyboard2.movement_alt.down,
+                &mut mapping.gamepad.movement_alt.down,
+            ],
+        ),
+        (
+            localization.get("move-left-alt"),
+            [
+                &mut mapping.keyboard1.movement_alt.left,
+                &mut mapping.keyboard2.movement_alt.left,
+                &mut mapping.gamepad.movement_alt.left,
+            ],
+        ),
+        (
+            localization.get("move-right-alt"),
+            [
+                &mut mapping.keyboard1.movement_alt.right,
+                &mut mapping.keyboard2.movement_alt.right,
+                &mut mapping.gamepad.movement_alt.right,
+            ],
+        ),
         (
             localization.get("jump"),
             [