[cmd] Add deadband trigger methods to CommandGenericHID

wpilibNewCommands/src/main/java/edu/wpi/first/wpilibj2/command/button/CommandGenericHID.java

@@ -23,6 +23,7 @@ public class CommandGenericHID {
       new HashMap<>();
   private final Map<EventLoop, Map<Pair<Integer, Double>, Trigger>> m_axisGreaterThanCache =
       new HashMap<>();
+  private final Map<EventLoop, Map<Pair<Integer, Double>, Trigger>> m_axisActive = new HashMap<>();
   private final Map<EventLoop, Map<Integer, Trigger>> m_povCache = new HashMap<>();
 
   /**
@@ -260,6 +261,37 @@ public Trigger axisGreaterThan(int axis, double threshold, EventLoop loop) {
         Pair.of(axis, threshold), k -> new Trigger(loop, () -> getRawAxis(axis) > threshold));
   }
 
+  /**
+   * Constructs a Trigger instance that is true when the axis value is active (non-zero) given a
+   * {@code deadband}, attached to the given loop.
+   *
+   * @param axis The axis to read, starting at 0
+   * @param deadband The value used to deadband the axis value. The trigger returns true if the
+   *     deadbanded value is non-zero.
+   * @param loop the event loop instance to attach the trigger to.
+   * @return a Trigger instance that is true when the deadbanded axis value is active (non-zero).
+   */
+  public Trigger axisActive(int axis, double deadband, EventLoop loop) {
+    var cache = m_axisActive.computeIfAbsent(loop, k -> new HashMap<>());
+    return cache.computeIfAbsent(
+        Pair.of(axis, deadband),
+        k -> new Trigger(loop, () -> Math.abs(getRawAxis(axis)) > deadband));
+  }
+
+  /**
+   * Constructs a Trigger instance that is true when the axis value is active (non-zero) given a
+   * {@code deadband}, attached to {@link CommandScheduler#getDefaultButtonLoop() the default
+   * command scheduler button loop}.
+   *
+   * @param axis The axis to read, starting at 0
+   * @param deadband The value used to deadband the axis value. The trigger returns true if the
+   *     deadbanded value is non-zero.
+   * @return a Trigger instance that is true when the deadbanded axis value is active (non-zero).
+   */
+  public Trigger axisActive(int axis, double deadband) {
+    return axisActive(axis, deadband, CommandScheduler.getInstance().getDefaultButtonLoop());
+  }
+
   /**
    * Get the value of the axis.
    *

wpilibNewCommands/src/main/native/cpp/frc2/command/button/CommandGenericHID.cpp

@@ -75,6 +75,13 @@ Trigger CommandGenericHID::AxisGreaterThan(int axis, double threshold,
   });
 }
 
+Trigger CommandGenericHID::AxisActive(int axis, double deadband,
+                                      frc::EventLoop* loop) const {
+  return Trigger(loop, [this, axis, deadband]() {
+    return std::abs(m_hid.GetRawAxis(axis)) > deadband;
+  });
+}
+
 void CommandGenericHID::SetRumble(frc::GenericHID::RumbleType type,
                                   double value) {
   m_hid.SetRumble(type, value);

wpilibNewCommands/src/main/native/include/frc2/command/button/CommandGenericHID.h

@@ -230,6 +230,22 @@ class CommandGenericHID {
       frc::EventLoop* loop =
           CommandScheduler::GetInstance().GetDefaultButtonLoop()) const;
 
+  /**
+   * Constructs a Trigger instance that is true when the axis value is active
+   * (non-zero) given a
+   * {@code deadband}, attached to the given loop.
+   *
+   * @param axis The axis to read, starting at 0
+   * @param deadband The value used to deadband the axis value. The trigger
+   * returns true if the deadbanded value is non-zero.
+   * @param loop the event loop instance to attach the trigger to.
+   * @return a Trigger instance that is true when the deadbanded axis value is
+   * active (non-zero).
+   */
+  Trigger AxisActive(int axis, double deadband,
+                     frc::EventLoop* loop = CommandScheduler::GetInstance()
+                                                .GetDefaultButtonLoop()) const;
+
   /**
    * Set the rumble output for the HID.
    *