Gamepad

package com.arcrobotics.ftclib.gamepad

The FTCLib provides enhanced Gamepad features. These classes are essentially extensions of the stock FTC SDK Gamepad features but with easier implementation methods.

GamepadKeys

Provides enum representations of the buttons, D-Pad, bumpers, and triggers. Buttons, D-Pad, and bumpers are stored in GamepadKeys.Button and triggers are stored in GamepadKeys.Trigger.

Buttons

Y

X

A

B

LEFT_BUMPER

RIGHT_BUMPER

BACK

START

DPAD_UP

DPAD_DOWN

DPAD_LEFT

DPAD_RIGHT

LEFT_STICK_BUTTON

RIGHT_STICK_BUTTON

Trigger

LEFT_TRIGGER

RIGHT_TRIGGER

// these are from the GamepadButton class that is used
// for command-based frameworks
GamepadButton grabButton = new GamepadButton(
    gamepad1, GamepadKeys.Button.A
);
GamepadButton releaseButton = new GamepadButton(
    gamepad2, GamepadKeys.Button.B
);

GamepadEx gamepadEx = new GamepadEx(gamepad1);

GamepadEx

An extension of the stock FTC SDK Gamepad class. Constructed simply from a Gamepad. Provides six intuitive value-getting methods:

  • getButton(): Given a GamepadKeys.Button, this method will check if that Button is pressed, returning a boolean of whether that Button is pressed.

gamepadEx.getButton(GamepadKeys.Button.A);
  • getTrigger(): Given a GamepadKeys.Trigger, this method will return the value of the Trigger (0 if unpressed, 1 if fully depressed).

gamepadEx.getTrigger(GamepadKeys.Trigger.RIGHT_TRIGGER);
  • getLeftY(): Returns the value of the y-axis of the left joystick (note that the value returned is the opposite of what would be returned from the standard gamepad object).

gamepadEx.getLeftY();
  • getRightY(): Returns the value of the y-axis of the right joystick

gamepadEx.getRightY();
  • getLeftX(): Returns the value of the x-axis of the left joystick

gamepadEx.getLeftX();
  • getRightX(): Returns the value of the x-axis of the right joystick

gamepadEx.getRightX();

KeyReader

The KeyReader interface is the base for objects that monitor an individual button or trigger on a gamepad. All Reader classes must implement these functions:

  • readValue(): Reads the current value of the key, true or false, and updates the values used by the reader. Returns nothing. This must be called once every loop.

  • isDown() : Checks if key is currently down. Will return a boolean of whether that key is pressed.

  • wasJustPressed() : Returns boolean whether the key is pressed, but only if it was previously not pressed.

  • wasJustReleased() : Returns boolean indicating whether the key is not pressed, but only if it was previously pressed.

  • stateJustChanged : Returns boolean indicating that the key's value has switched.

TriggerReader

The TriggerReader class implements the KeyReader interface. Because GamepadEx Triggers return a double , the TriggerReader class interprets a value of greater than 0.5 as a trigger press.

The following constructs a new Trigger Reader with a GamepadEx gamepad and GamepadKeys.Trigger trigger.

TriggerReader triggerReader = new TriggerReader(
    gamepadEx, GamepadKeys.Trigger.RIGHT_TRIGGER
);

Below are the different methods you can use with the trigger reader.

triggerReader.isDown();
triggerReader.readValue();
triggerReader.stateJustChanged();
triggerReader.wasJustPressed();
triggerReader.wasJustReleased();

ButtonReader

The ButtonReaderclass implements the KeyReader interface. It checks if a button is pressed, released, or is down.

ButtonReader reader = new ButtonReader(
    gamepadEx, GamepadKeys.Button.A
);
  • ButtonReader(GamepadEx gamepad, GamepadKeys.Button button): Constructs a new Button Reader with a GamepadEx gamepad and a GamepadKeys.Button button.

  • ButtonReader(BooleanSupplier supplier): Constructs a new Button Reader using the value of a boolean supplier instead of a gamepad, which allows reading value states easily without a gamepad.

reader.readValue();
reader.wasJustPressed();
reader.stateJustChanged();
reader.isDown();
reader.wasJustReleased();

The GamepadEx objects actually contain ButtonReaders. For every GamepadKeys.Button, there is a matching ButtonReader entry in the map. It is stored internally as a Map<GamepadKeys.Button, ButtonReader>. This allows you to use these features just with the GamepadEx class.

// create the gamepad
GamepadEx myGamepad = new Gamepad(gamepad1);

/** The methods for using the ButtonReaders **/
myGamepad.wasJustPressed(GamepadKeys.Button.A);
myGamepad.stateJustChanged(GamepadKeys.Button.A);
myGamepad.isDown(GamepadKeys.Button.A);
myGamepad.wasJustReleased(GamepadKeys.Button.A);

// pass the GamepadKeys.Button that you want to read
// into the method argument

// to read all buttons at once, perform a single call
myGamepad.readButtons();
/*
this is the equivalent of calling readValue() once
for all your readers
*/

ToggleButtonReader

ToggleButtonReader toggleButtonReader = new ToggleButtonReader(
    gamepadEx, GamepadKeys.Button.A
);

The ToggleButtonReader class extends ButtonReader and adds the ability to get the status of a toggle. readValue() needs to be run in a loop to get the state of the toggle.

getState() : Gets the toggle value of a button or boolean supplier.

toggleButtonReader.getState();

Usage

GamepadEx toolOp = new GamepadEx(gamepad2);
ToggleButtonReader aReader = new ToggleButtonReader(
  toolOp, GamepadKeys.Button.A
);

while (...) {
  if (aReader.getState()) {
    // if toggle state true
  } else {
    // if toggle state false
  }
  aReader.readValue();
}

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