Add new behavior for a button that sends separate keypresses on press and release. This required a refactor of the button abstraction as well.

Joystick.cpp

@@ -1,5 +1,8 @@
 #include "Joystick.h"
 #include <Arduino.h>
+#include <list>
+
+using std::list;
 
 bool operator ==(JoyReport a, JoyReport b){
   for (uint8_t i=0; i < JOYSTICK_NUM_AXES; i++) {
@@ -17,16 +20,13 @@ bool operator !=(JoyReport a, JoyReport b){
 
 Joystick::Joystick(bool debug) {
   _debug = debug;
-  _num_buttons = 0;
+  _last_button_index = 0;
   _num_axes = 0;
   _have_pulsed_button = false;
   
   for (uint8_t i=0; i < JOYSTICK_NUM_AXES; i++) {
     _joyReport.axis[i] = 0;
   }
-  for (uint8_t i=0; i < JOYSTICK_NUM_BYTES; i++) {
-    _joyReport.button[i] = 0;
-  }
 }
 
 void Joystick::Init() {
@@ -42,9 +42,21 @@ void Joystick::AddButton(uint8_t pin, ButtonType type, bool pullup) {
   Button button;
   button.type = type;
   button.bouncer.attach(pin, mode);
+  uint8_t index = _last_button_index + 1;
+  uint8_t increment = 1;
+  button.index0 = index;
 
-  _buttons[_num_buttons] = button;
-  _num_buttons++;
+  if (type == BUTTON_PULSED_DOUBLE_ACTION_SPLIT) {
+    increment = 2;
+    button.index1 = index + 1;
+  }
+  
+  if (_last_button_index + increment > JOYSTICK_NUM_BUTTONS) {
+      // todo: fail here
+  }
+
+  _buttons.push_back(button);
+  last_button_index += increment;
 
   if (type & _BUTTON_PULSED_TYPES) _have_pulsed_button = true;
 }
@@ -57,8 +69,8 @@ void Joystick::AddAxis(uint8_t pin) {
 void Joystick::Update() {
   JoyReport oldReport = _joyReport;
   
-  for (int i = 0; i < _num_buttons; i++) {
-    _UpdateButton(i);
+  for (list<Button>::iterator cursor = _buttons.begin(); cursor != _buttons.end(); cursor++) {
+    _UpdateButton(*cursor);
   }
 
   for (int i = 0; i < _num_axes; i++) {
@@ -100,8 +112,9 @@ void Joystick::ReleaseAllButtons() {
 }
 
 void Joystick::_ReleasePulsedButtons() {
-  for (uint8_t i = 0; i < _num_buttons; i++) {
-    if (_buttons[i].type & _BUTTON_PULSED_TYPES) ReleaseButton(i);
+  for (list<Button>::iterator i = _buttons.begin(); i != buttons.end(); i++) {
+    if (i->type & _BUTTON_PULSED_TYPES) ReleaseButton(i->index0);
+    if (i->type & BUTTON_PULSED_DOUBLE_ACTION_SPLIT) ReleaseButton(i->index1);
   }
 }
 
@@ -124,20 +137,23 @@ void Joystick::Write() {
   delay(250);
 }
 
-void Joystick::_UpdateButton(uint8_t index) {
-  Button* button = &_buttons[index];
+void Joystick::_UpdateButton(Button* button) {
   bool changed = button->bouncer.update();
 
   switch (button->type) {
-    case BUTTON_LATCHED:
-      if (button->bouncer.rose()) PressButton(index);
-      else if (button->bouncer.fell()) ReleaseButton(index);
+    case BUTTON_PASSTHRU:
+      if (button->bouncer.rose()) PressButton(button->index0);
+      else if (button->bouncer.fell()) ReleaseButton(button->index0);
       break;
     case BUTTON_PULSED:
-      if (button->bouncer.rose()) PressButton(index);
+      if (button->bouncer.rose()) PressButton(button->index0);
       break;
     case BUTTON_PULSED_DOUBLE_ACTION:
-      if (changed) PressButton(index);
+      if (changed) PressButton(button->index0);
+      break;
+    case BUTTON_PULSED_DOUBLE_ACTION_SPLIT:
+      if (button->bouncer.rose()) PressButton(button->index0);
+      else if (button->bouncer.fell()) PressButton(button->index1);
       break;
     default:
       if (_debug) {

Joystick.h

@@ -3,6 +3,9 @@
 
 #include <Arduino.h>
 #include <Bounce2.h>
+#include <list>
+
+using std::list;
 
 // If you're using the arduino-big-joystick firmware, these numbers can't be
 // changed. If you're writing your own Report Descriptor, tune these to match by
@@ -16,9 +19,10 @@
 #define JOYSTICK_NUM_BYTES (JOYSTICK_NUM_BUTTONS+7)/8
 
 enum ButtonType {
-  BUTTON_LATCHED = 0x1,
-  BUTTON_PULSED = 0x2,
-  BUTTON_PULSED_DOUBLE_ACTION = 0x4
+  BUTTON_PASSTHRU = 0x1, // always use the (debounced) absolute state of the input
+  BUTTON_PULSED = 0x2, // on button press, send an on signal followed immediately by an off signal.
+  BUTTON_PULSED_DOUBLE_ACTION = 0x4, // Send a button press twice - once for press and once for release.
+  BUTTON_PULSED_DOUBLE_ACTION_SPLIT = 0x8 // Send two separate button presses - one button on press, another on release.
 };
 
 struct JoyReport {
@@ -29,6 +33,9 @@ struct JoyReport {
 struct Button {
   ButtonType type;
   Bounce bouncer;
+  uint8_t index0;
+  uint8_t index1;
+  bool inverted = false; // if true, send button press on release and vice versa.
 };
 
 bool operator ==(JoyReport a, JoyReport b);
@@ -40,10 +47,10 @@ class Joystick {
     void Init();
     void Update();
     
-    void AddButton(uint8_t pin, ButtonType type, bool pullup=false);
+    void AddButton(uint8_t pin, ButtonType type, bool pullup=true);
     void AddAxis(uint8_t pin); // Axes don't actually work yet!
     
-    // These functions are deprecated and may become private in a future
+    // Public access to these functions is deprecated and they may become private in a future
     // version. Prefer the above API instead.
     void SetAxis(uint8_t axis, int16_t value);
     void PressButton(uint8_t button);
@@ -56,8 +63,8 @@ class Joystick {
     void _UpdateButton(uint8_t index);
     void _UpdateAxis(uint8_t index);
     
-    Button _buttons[JOYSTICK_NUM_BUTTONS];
-    uint8_t _num_buttons;
+    list<Button> _buttons;
+    uint8_t _last_button_index;
     bool _have_pulsed_button;
 
     uint8_t _axes[JOYSTICK_NUM_AXES];
@@ -68,6 +75,6 @@ class Joystick {
 };
 
 // Internal use only.
-#define _BUTTON_PULSED_TYPES (BUTTON_PULSED | BUTTON_PULSED_DOUBLE_ACTION)
+#define _BUTTON_PULSED_TYPES (BUTTON_PULSED | BUTTON_PULSED_DOUBLE_ACTION | BUTTON_PULSED_DOUBLE_ACTION_SPLIT)
 
 #endif

Readme.md

@@ -2,7 +2,7 @@
 This is a library that builds and sends USB HID Joystick reports, making it easy to build USB Joysticks with Arduino.
 
 ## Dependencies
-* Your Arduino's USB communication chip be programmed with the arduino-big-joystick firmware (or similar). See <https://github.com/harlequin-tech/arduino-usb> for more info.
+* Your Arduino's USB communication chip must be programmed with the arduino-big-joystick firmware (or similar). See <https://github.com/harlequin-tech/arduino-usb> for more info.
 * The Bounce2 library, available at <https://github.com/thomasfredericks/Bounce2>.
 
 ## Installation