- correct the mouse button iterator, it now works correctly

- correct `is_mouse_button_pressed()`, now uses mask correctly
- add examples for `mouse_state()` and `relative_mouse_state()`

examples/mouse-state.rs

@@ -0,0 +1,47 @@
+extern crate sdl2;
+
+use sdl2::event::Event;
+use sdl2::mouse::MouseButton;
+use std::collections::HashSet;
+use std::time::Duration;
+
+pub fn main() {
+    let sdl_context = sdl2::init().unwrap();
+    let video_subsystem = sdl_context.video().unwrap();
+
+    let _window = video_subsystem.window("Mouse", 800, 600)
+        .position_centered()
+        .build()
+        .unwrap();
+
+    let mut events = sdl_context.event_pump().unwrap();
+
+    let mut prev_buttons = HashSet::new();
+
+    'running: loop {
+        for event in events.poll_iter() {
+            match event {
+                Event::Quit {..} => break 'running,
+                _ => ()
+            }
+        }
+
+        // get a mouse state
+        let state = events.mouse_state();
+
+        // Create a set of pressed Keys.
+        let buttons = state.pressed_mouse_buttons().collect();
+
+        // Get the difference between the new and old sets.
+        let new_buttons = &buttons - &prev_buttons;
+        let old_buttons = &prev_buttons - &buttons;
+
+        if !new_buttons.is_empty() || !old_buttons.is_empty() {
+            println!("X = {:?}, Y = {:?} : {:?} -> {:?}", state.x(), state.y(),  new_buttons, old_buttons);
+        }
+
+        prev_buttons = buttons;
+
+        std::thread::sleep(Duration::from_millis(100));
+    }
+}

examples/relative-mouse-state.rs

@@ -0,0 +1,39 @@
+extern crate sdl2;
+
+use sdl2::event::Event;
+use sdl2::mouse::MouseButton;
+use std::time::Duration;
+
+pub fn main() {
+    let sdl_context = sdl2::init().unwrap();
+    let video_subsystem = sdl_context.video().unwrap();
+
+    let _window = video_subsystem.window("Mouse", 800, 600)
+        .position_centered()
+        .build()
+        .unwrap();
+
+    let mut events = sdl_context.event_pump().unwrap();
+
+    let mut state = events.relative_mouse_state();
+    let mut old_x = 0;
+    let mut old_y = 0;
+
+    'running: loop {
+        for event in events.poll_iter() {
+            match event {
+                Event::Quit {..} => break 'running,
+                _ => ()
+            }
+        }
+
+        // get a mouse state using mouse_state() so as not to call
+        // relative_mouse_state() twice and get a false position reading
+        if events.mouse_state().is_mouse_button_pressed(MouseButton::Left) {
+            state = events.relative_mouse_state();
+            println!("Relative - X = {:?}, Y = {:?}", state.x(), state.y());
+        }
+
+        std::thread::sleep(Duration::from_millis(100));
+    }
+}

src/sdl2/mouse/mod.rs

@@ -183,22 +183,22 @@ impl MouseButton {
 #[derive(Copy, Clone, Eq, PartialEq, Hash)]
 pub struct MouseState {
     mouse_state: u32,
-    x: u32,
-    y: u32
+    x: i32,
+    y: i32
 }
 
 impl MouseState {
     pub fn new(_e: &EventPump) -> MouseState {
         let mut x = 0;
         let mut y = 0;
-        let mouse_state = unsafe {
+        let mouse_state: u32 = unsafe {
             ll::SDL_GetMouseState(&mut x, &mut y)
         };
 
         MouseState {
             mouse_state: mouse_state,
-            x: x as u32,
-            y: y as u32
+            x: x as i32,
+            y: y as i32
         }
     }
 
@@ -233,18 +233,25 @@ impl MouseState {
     /// Tests if the X2 mouse button was pressed.
     pub fn x2(&self) -> bool { (self.mouse_state & ll::SDL_BUTTON_X2MASK) != 0 }
 
+    /// Returns the x coordinate of the state
+    pub fn x(&self) -> i32 { self.x }
+
+    /// Returns the y coordinate of the state
+    pub fn y(&self) -> i32 { self.y }
+
     /// Returns true if the mouse button is pressed.
     ///
     /// # Example
     /// ```no_run
     /// use sdl2::mouse::MouseButton;
     ///
-    /// fn is_a_pressed(e: &sdl2::EventPump) -> bool {
+    /// fn is_left_pressed(e: &sdl2::EventPump) -> bool {
     ///     e.mouse_state().is_mouse_button_pressed(MouseButton::Left)
     /// }
     /// ```
     pub fn is_mouse_button_pressed(&self, mouse_button: MouseButton) -> bool {
-        self.mouse_state<<((mouse_button as u32)-1) != 0
+        let mask = 1 << ((mouse_button as u32)-1);
+        self.mouse_state & mask != 0
     }
 
     /// Returns an iterator all mouse buttons with a boolean indicating if the scancode is pressed.
@@ -305,12 +312,13 @@ impl<'a> Iterator for MouseButtonIterator<'a> {
     type Item = (MouseButton, bool);
 
     fn next(&mut self) -> Option<(MouseButton, bool)> {
-        if self.index < MouseButton::X2 as usize {
+        if self.index < MouseButton::X2 as usize +1 {
             let index = self.index;
             self.index += 1;
 
             if let Some(mouse_button) = FromPrimitive::from_usize(index) {
-                let pressed = self.mouse_state&(MouseButton::Middle as u32) != 0;
+                let mask = 1 << ((mouse_button as u32)-1);
+                let pressed = self.mouse_state & mask != 0;
 
                 Some((mouse_button, pressed))
             } else {

src/sdl2/mouse/relative.rs

@@ -7,8 +7,8 @@ use super::{MouseButton, MouseButtonIterator, PressedMouseButtonIterator};
 #[derive(Copy, Clone, Eq, PartialEq, Hash)]
 pub struct RelativeMouseState {
     mouse_state: u32,
-    x: u32,
-    y: u32
+    x: i32,
+    y: i32
 }
 
 impl RelativeMouseState {
@@ -22,8 +22,8 @@ impl RelativeMouseState {
 
         RelativeMouseState {
             mouse_state: mouse_state,
-            x: x as u32,
-            y: y as u32
+            x: x as i32,
+            y: y as i32
         }
     }
 
@@ -58,18 +58,25 @@ impl RelativeMouseState {
     /// Tests if the X2 mouse button was pressed.
     pub fn x2(&self) -> bool { (self.mouse_state & ll::SDL_BUTTON_X2MASK) != 0 }
 
+    /// Returns the x coordinate of the state
+    pub fn x(&self) -> i32 { self.x }
+
+    /// Returns the y coordinate of the state
+    pub fn y(&self) -> i32 { self.y }
+
     /// Returns true if the mouse button is pressed.
     ///
     /// # Example
     /// ```no_run
     /// use sdl2::mouse::MouseButton;
     ///
-    /// fn is_a_pressed(e: &sdl2::EventPump) -> bool {
+    /// fn is_left_pressed(e: &sdl2::EventPump) -> bool {
     ///     e.mouse_state().is_mouse_button_pressed(MouseButton::Left)
     /// }
     /// ```
     pub fn is_mouse_button_pressed(&self, mouse_button: MouseButton) -> bool {
-        self.mouse_state<<((mouse_button as u32)-1) != 0
+        let mask = 1 << ((mouse_button as u32)-1);
+        self.mouse_state & mask != 0
     }
 
     /// Returns an iterator all mouse buttons with a boolean indicating if the scancode is pressed.