Configurable 2 fingers pinch gesture

README.md

@@ -55,8 +55,17 @@ right_down = ""
 down = ""
 left = ""
 right = ""
+
+[commands.pinch]
+in = ""
+out = ""
+distance=""
 ```
 
+* `distance` variable in `commands.pinch` sets the distance between fingers where it shold trigger.
+  Defaults to `0.5` which means fingers should travel exactly half way from their initial position.
+
+
 ### Repository versions
 
 ![](https://img.shields.io/aur/version/gebaar.svg?style=flat)  
@@ -77,6 +86,7 @@ down = "bspc node -f south"
 left = "bspc node -f west"
 right = "bspc node -f east"
 
+
 [commands.swipe.four]
 left_up = ""
 right_up = ""
@@ -86,16 +96,24 @@ right_down = ""
 down = ""
 left = "bspc desktop -f prev"
 right = "bspc desktop -f next"
+
+[commands.pinch]
+in = "xdotool key Control_L+equal"
+out = "xdotool key Control_L+minus"
+ditance="0.1"
 ```
 
 Add `gebaard -b` to `~/.config/bspwm/bspwmrc`
 
 ### State of the project
 
 - [x] Receiving swipe events from libinput
-- [ ] Receiving pinch/zoom events from libinput
+- [x] Receiving pinch/zoom events from libinput
+  - [ ] Support continous pinch
+  - [ ] Support pinch-and-rotate gestures
 - [ ] Receiving rotation events from libinput
 - [x] Converting libinput events to motions
 - [x] Running commands based on motions
 - [x] Refactor code to be up to Release standards, instead of testing-hell
 
+

src/config/config.cpp

@@ -1,17 +1,17 @@
 /*
     gebaar
     Copyright (C) 2019   coffee2code
-    
+
     This program is free software: you can redistribute it and/or modify
     it under the terms of the GNU General Public License as published by
     the Free Software Foundation, either version 3 of the License, or
     (at your option) any later version.
-    
+
     This program is distributed in the hope that it will be useful,
     but WITHOUT ANY WARRANTY; without even the implied warranty of
     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
     GNU General Public License for more details.
-    
+
     You should have received a copy of the GNU General Public License
     along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */
@@ -61,6 +61,10 @@ void gebaar::config::Config::load_config()
             swipe_four_commands[8] = *config->get_qualified_as<std::string>("commands.swipe.four.down");
             swipe_four_commands[9] = *config->get_qualified_as<std::string>("commands.swipe.four.right_down");
 
+            pinch_commands[PINCH_IN] = *config->get_qualified_as<std::string>("commands.pinch.out");
+            pinch_commands[PINCH_OUT] = *config->get_qualified_as<std::string>("commands.pinch.in");
+            pinch_commands[DISTANCE] = *config->get_qualified_as<std::string>("commands.pinch.distance");
+
             loaded = true;
         }
     }

src/config/config.h

@@ -1,17 +1,17 @@
 /*
     gebaar
     Copyright (C) 2019   coffee2code
-    
+
     This program is free software: you can redistribute it and/or modify
     it under the terms of the GNU General Public License as published by
     the Free Software Foundation, either version 3 of the License, or
     (at your option) any later version.
-    
+
     This program is distributed in the hope that it will be useful,
     but WITHOUT ANY WARRANTY; without even the implied warranty of
     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
     GNU General Public License for more details.
-    
+
     You should have received a copy of the GNU General Public License
     along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */
@@ -33,8 +33,12 @@ namespace gebaar::config {
 
         void load_config();
 
+
+        enum pinches {PINCH_IN, PINCH_OUT, DISTANCE};
+
         std::string swipe_three_commands[10];
         std::string swipe_four_commands[10];
+        std::string pinch_commands[10];
 
     private:
         bool config_file_exists();

src/io/input.cpp

@@ -1,17 +1,17 @@
 /*
     gebaar
     Copyright (C) 2019   coffee2code
-    
+
     This program is free software: you can redistribute it and/or modify
     it under the terms of the GNU General Public License as published by
     the Free Software Foundation, either version 3 of the License, or
     (at your option) any later version.
-    
+
     This program is distributed in the hope that it will be useful,
     but WITHOUT ANY WARRANTY; without even the implied warranty of
     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
     GNU General Public License for more details.
-    
+
     You should have received a copy of the GNU General Public License
     along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */
@@ -28,6 +28,7 @@ gebaar::io::Input::Input(std::shared_ptr<gebaar::config::Config> const& config_p
 {
     config = config_ptr;
     gesture_swipe_event = {};
+    gesture_pinch_event = {};
 }
 
 /**
@@ -42,6 +43,54 @@ bool gebaar::io::Input::initialize_context()
     return libinput_udev_assign_seat(libinput, "seat0")==0;
 }
 
+
+
+/**
+ * Pinch Gesture
+ * Currently supporting only "one shot" pinch-in and pinch-out gestures.
+ * @param gev Gesture Event
+ * @param begin Boolean to denote begin or continuation of gesture.
+ **/
+void gebaar::io::Input::handle_pinch_event(libinput_event_gesture* gev, bool begin)
+{
+    if (begin) {
+        gesture_pinch_event.fingers = libinput_event_gesture_get_finger_count(gev);
+        // Get pinch distance
+        try {
+          gesture_pinch_event.distance = std::stod(config->pinch_commands[config->DISTANCE]);
+        }
+        catch (const std::invalid_argument &ia) {
+          // Set default distance
+          gesture_pinch_event.distance = DEFAULT_DISTANCE;
+        }
+        // Reset pinch data
+        gesture_pinch_event.scale = DEFAULT_SCALE;
+        gesture_pinch_event.executed = false;
+    }
+    else {
+        // Ignore input after command execution
+        if (gesture_pinch_event.executed) return;
+        double new_scale = libinput_event_gesture_get_scale(gev);
+        if (new_scale > gesture_pinch_event.scale) {
+            // Scale up
+            // Add 1 to required distance to get 2 > x > 1
+            if (new_scale > 1 + gesture_pinch_event.distance) {
+                std::system(config->pinch_commands[config->PINCH_IN].c_str());
+                gesture_pinch_event.executed = true;
+            }
+        }
+        else {
+            // Scale Down
+            // Substract from 1 to have inverted value for pinch in gesture
+            if (gesture_pinch_event.scale < 1 - gesture_pinch_event.distance) {
+                std::system(config->pinch_commands[config->PINCH_OUT].c_str());
+                gesture_pinch_event.executed = true;
+            }
+        }
+        gesture_pinch_event.scale = new_scale;
+    }
+}
+
 /**
  * This event has no coordinates, so it's an event that gives us a begin or end signal.
  * If it begins, we get the amount of fingers used.
@@ -169,6 +218,15 @@ void gebaar::io::Input::handle_event()
         case LIBINPUT_EVENT_GESTURE_SWIPE_END:
             handle_swipe_event_without_coords(libinput_event_get_gesture_event(libinput_event), false);
             break;
+        case LIBINPUT_EVENT_GESTURE_PINCH_BEGIN:
+            handle_pinch_event(libinput_event_get_gesture_event(libinput_event), true);
+            break;
+        case LIBINPUT_EVENT_GESTURE_PINCH_UPDATE:
+            handle_pinch_event(libinput_event_get_gesture_event(libinput_event), false);
+            break;
+        case LIBINPUT_EVENT_GESTURE_PINCH_END:
+            handle_pinch_event(libinput_event_get_gesture_event(libinput_event), false);
+            break;
         case LIBINPUT_EVENT_NONE:
             break;
         case LIBINPUT_EVENT_DEVICE_ADDED:
@@ -209,12 +267,6 @@ void gebaar::io::Input::handle_event()
             break;
         case LIBINPUT_EVENT_TABLET_PAD_STRIP:
             break;
-        case LIBINPUT_EVENT_GESTURE_PINCH_BEGIN:
-            break;
-        case LIBINPUT_EVENT_GESTURE_PINCH_UPDATE:
-            break;
-        case LIBINPUT_EVENT_GESTURE_PINCH_END:
-            break;
         case LIBINPUT_EVENT_SWITCH_TOGGLE:
             break;
         }

src/io/input.h

@@ -1,17 +1,17 @@
 /*
     gebaar
     Copyright (C) 2019   coffee2code
-    
+
     This program is free software: you can redistribute it and/or modify
     it under the terms of the GNU General Public License as published by
     the Free Software Foundation, either version 3 of the License, or
     (at your option) any later version.
-    
+
     This program is distributed in the hope that it will be useful,
     but WITHOUT ANY WARRANTY; without even the implied warranty of
     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
     GNU General Public License for more details.
-    
+
     You should have received a copy of the GNU General Public License
     along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */
@@ -24,13 +24,26 @@
 #include <zconf.h>
 #include "../config/config.h"
 
+#define DEFAULT_SCALE    1.0
+#define DEFAULT_DISTANCE 0.5
+
+
 namespace gebaar::io {
     struct gesture_swipe_event {
         int fingers;
         double x;
         double y;
     };
 
+    struct gesture_pinch_event {
+        int fingers;
+        double scale;
+        double angle;
+
+        double distance;
+        bool executed;
+    };
+
     class Input {
     public:
         Input(std::shared_ptr<gebaar::config::Config> const& config_ptr);
@@ -48,6 +61,7 @@ namespace gebaar::io {
         struct libinput_event* libinput_event;
         struct udev* udev;
         struct gesture_swipe_event gesture_swipe_event;
+        struct gesture_pinch_event gesture_pinch_event;
 
         bool initialize_context();
 
@@ -74,6 +88,9 @@ namespace gebaar::io {
         void handle_swipe_event_without_coords(libinput_event_gesture* gev, bool begin);
 
         void handle_swipe_event_with_coords(libinput_event_gesture* gev);
+
+        void handle_pinch_event(libinput_event_gesture* gev, bool begin);
+
     };
 }