add get_keys_released method to Window (#151)

.gitignore

@@ -1,2 +1,4 @@
 target
 Cargo.lock
+*.idea
+*.iml

examples/noise.rs

@@ -58,6 +58,16 @@ fn main() {
             }
         });
 
+        window.get_keys_released().map(|keys| {
+            for t in keys {
+                match t {
+                    Key::W => println!("released w!"),
+                    Key::T => println!("released t!"),
+                    _ => (),
+                }
+            }
+        });
+
         window
             .update_with_buffer(&buffer, new_size.0, new_size.1)
             .unwrap();

src/key_handler.rs

@@ -91,6 +91,20 @@ impl KeyHandler {
         Some(keys)
     }
 
+    pub fn get_keys_released(&self) -> Option<Vec<Key>> {
+        let mut keys: Vec<Key> = Vec::new();
+
+        for (idx, is_down) in self.keys.iter().enumerate() {
+            if !(*is_down) && self.is_key_index_released(idx) {
+                unsafe {
+                    keys.push(mem::transmute(idx as u8));
+                }
+            }
+        }
+
+        Some(keys)
+    }
+
     #[inline]
     pub fn is_key_down(&self, key: Key) -> bool {
         return self.keys[key as usize];
@@ -134,6 +148,11 @@ impl KeyHandler {
     #[inline]
     pub fn is_key_released(&self, key: Key) -> bool {
         let idx = key as usize;
+        return self.is_key_index_released(idx);
+    }
+
+    #[inline]
+    fn is_key_index_released(&self, idx: usize) -> bool {
         return self.keys_prev[idx] && !self.keys[idx];
     }
 }

src/lib.rs

@@ -561,6 +561,29 @@ impl Window {
         self.0.get_keys_pressed(repeat)
     }
 
+    ///
+    /// Get the current released keys.
+    ///
+    /// # Examples
+    ///
+    /// ```no_run
+    /// # use minifb::*;
+    /// # let mut window = Window::new("Test", 640, 400, WindowOptions::default()).unwrap();
+    /// window.get_keys_released().map(|keys| {
+    ///     for t in keys {
+    ///         match t {
+    ///             Key::W => println!("released w"),
+    ///             Key::T => println!("released t"),
+    ///             _ => (),
+    ///         }
+    ///     }
+    /// });
+    /// ```
+    #[inline]
+    pub fn get_keys_released(&self) -> Option<Vec<Key>> {
+        self.0.get_keys_released()
+    }
+
     ///
     /// Check if a single key is down.
     ///

src/os/macos/mod.rs

@@ -468,6 +468,11 @@ impl Window {
         self.key_handler.get_keys_pressed(repeat)
     }
 
+    #[inline]
+    pub fn get_keys_released(&self) -> Option<Vec<Key>> {
+        self.key_handler.get_keys_released()
+    }
+
     #[inline]
     pub fn is_key_down(&self, key: Key) -> bool {
         self.key_handler.is_key_down(key)

src/os/redox/mod.rs

@@ -189,6 +189,10 @@ impl Window {
         self.key_handler.get_keys_pressed(repeat)
     }
 
+    pub fn get_keys_released(&self) -> Option<Vec<Key>> {
+        self.key_handler.get_keys_released()
+    }
+
     pub fn is_key_down(&self, key: Key) -> bool {
         self.key_handler.is_key_down(key)
     }

src/os/unix/mod.rs

@@ -155,6 +155,13 @@ impl Window {
         }
     }
 
+    pub fn get_keys_released(&self) -> Option<Vec<Key>> {
+        match *self {
+            Window::X11(ref w) => w.get_keys_released(),
+            Window::Wayland(ref _w) => unimplemented!(),
+        }
+    }
+
     pub fn is_key_down(&self, key: Key) -> bool {
         match *self {
             Window::X11(ref w) => w.is_key_down(key),

src/os/unix/x11.rs

@@ -590,6 +590,11 @@ impl Window {
         self.key_handler.get_keys_pressed(repeat)
     }
 
+    #[inline]
+    pub fn get_keys_released(&self) -> Option<Vec<Key>> {
+        self.key_handler.get_keys_released()
+    }
+
     #[inline]
     pub fn is_key_down(&self, key: Key) -> bool {
         self.key_handler.is_key_down(key)

src/os/windows/mod.rs

@@ -700,6 +700,11 @@ impl Window {
         self.key_handler.get_keys_pressed(repeat)
     }
 
+    #[inline]
+    pub fn get_keys_released(&self) -> Option<Vec<Key>> {
+        self.key_handler.get_keys_released()
+    }
+
     #[inline]
     pub fn is_key_down(&self, key: Key) -> bool {
         self.key_handler.is_key_down(key)