Emscripten (#357)

* impl modifiers state for emscripten

* impl mouse events emscripten

* impl mousemotion for emscripten

it is useful when cursor is grabbed

* changelog

CHANGELOG.md

@@ -18,6 +18,7 @@
 - `WindowEvent`s `MouseMoved`, `MouseEntered`, and `MouseLeft` have been renamed to
 `CursorMoved`, `CursorEntered`, and `CursorLeft`.
 - New `DeviceEvent`s added, `MouseMotion` and `MouseWheel`.
+- Impl `ModifiersState`, `MouseMove`, `MouseInput`, `MouseMotion` for emscripten backend.
 
 # Version 0.8.3 (2017-10-11)
 

src/platform/emscripten/ffi.rs

@@ -2,7 +2,7 @@
 #![allow(non_snake_case)]
 #![allow(non_camel_case_types)]
 
-use std::os::raw::{c_int, c_char, c_void, c_ulong, c_double};
+use std::os::raw::{c_int, c_char, c_void, c_ulong, c_double, c_long, c_ushort};
 
 pub type EM_BOOL = c_int;
 pub type EM_UTF8 = c_char;
@@ -76,6 +76,11 @@ pub type em_key_callback_func = Option<unsafe extern "C" fn(
     keyEvent: *const EmscriptenKeyboardEvent,
     userData: *mut c_void) -> EM_BOOL>;
 
+pub type em_mouse_callback_func = Option<unsafe extern "C" fn(
+    eventType: c_int,
+    mouseEvent: *const EmscriptenMouseEvent,
+    userData: *mut c_void) -> EM_BOOL>;
+
 pub type em_pointerlockchange_callback_func = Option<unsafe extern "C" fn(
     eventType: c_int,
     pointerlockChangeEvent: *const EmscriptenPointerlockChangeEvent,
@@ -129,6 +134,34 @@ impl Clone for EmscriptenKeyboardEvent {
     fn clone(&self) -> Self { *self }
 }
 
+#[repr(C)]
+#[derive(Debug, Copy, Clone)]
+pub struct EmscriptenMouseEvent {
+    pub timestamp: f64,
+    pub screenX: c_long,
+    pub screenY: c_long,
+    pub clientX: c_long,
+    pub clientY: c_long,
+    pub ctrlKey: c_int,
+    pub shiftKey: c_int,
+    pub altKey: c_int,
+    pub metaKey: c_int,
+    pub button: c_ushort,
+    pub buttons: c_ushort,
+    pub movementX: c_long,
+    pub movementY: c_long,
+    pub targetX: c_long,
+    pub targetY: c_long,
+    pub canvasX: c_long,
+    pub canvasY: c_long,
+    pub padding: c_long,
+}
+#[test]
+fn bindgen_test_layout_EmscriptenMouseEvent() {
+    assert_eq!(mem::size_of::<EmscriptenMouseEvent>(), 120usize);
+    assert_eq!(mem::align_of::<EmscriptenMouseEvent>(), 8usize);
+}
+
 #[repr(C)]
 pub struct EmscriptenPointerlockChangeEvent {
     pub isActive: c_int,
@@ -172,6 +205,21 @@ extern "C" {
         useCapture: EM_BOOL, callback: em_key_callback_func)
         -> EMSCRIPTEN_RESULT;
 
+    pub fn emscripten_set_mousemove_callback(
+        target: *const c_char, user_data: *mut c_void,
+        use_capture: EM_BOOL, callback: em_mouse_callback_func)
+        -> EMSCRIPTEN_RESULT;
+
+    pub fn emscripten_set_mousedown_callback(
+        target: *const c_char, user_data: *mut c_void,
+        use_capture: EM_BOOL, callback: em_mouse_callback_func)
+        -> EMSCRIPTEN_RESULT;
+
+    pub fn emscripten_set_mouseup_callback(
+        target: *const c_char, user_data: *mut c_void,
+        use_capture: EM_BOOL, callback: em_mouse_callback_func)
+        -> EMSCRIPTEN_RESULT;
+
     pub fn emscripten_hide_mouse();
 
     pub fn emscripten_get_device_pixel_ratio() -> f64;

src/platform/emscripten/mod.rs

@@ -170,6 +170,59 @@ fn show_mouse() {
     }
 }
 
+extern "C" fn mouse_callback(
+    event_type: c_int,
+    event: *const ffi::EmscriptenMouseEvent,
+    event_queue: *mut c_void) -> ffi::EM_BOOL
+{
+    unsafe {
+        let queue: &RefCell<VecDeque<::Event>> = mem::transmute(event_queue);
+
+        match event_type {
+            ffi::EMSCRIPTEN_EVENT_MOUSEMOVE => {
+                queue.borrow_mut().push_back(::Event::WindowEvent {
+                    window_id: ::WindowId(WindowId(0)),
+                    event: ::WindowEvent::CursorMoved {
+                        device_id: ::DeviceId(DeviceId),
+                        position: ((*event).canvasX as f64, (*event).canvasY as f64),
+                    }
+                });
+                queue.borrow_mut().push_back(::Event::DeviceEvent {
+                    device_id: ::DeviceId(DeviceId),
+                    event: ::DeviceEvent::MouseMotion {
+                        delta: ((*event).movementX as f64, (*event).movementY as f64),
+                    }
+                });
+            },
+            mouse_input @ ffi::EMSCRIPTEN_EVENT_MOUSEDOWN |
+            mouse_input @ ffi::EMSCRIPTEN_EVENT_MOUSEUP => {
+                let button = match (*event).button {
+                    0 => ::MouseButton::Left,
+                    1 => ::MouseButton::Middle,
+                    2 => ::MouseButton::Right,
+                    other => ::MouseButton::Other(other as u8),
+                };
+                let state = match mouse_input {
+                    ffi::EMSCRIPTEN_EVENT_MOUSEDOWN => ::ElementState::Pressed,
+                    ffi::EMSCRIPTEN_EVENT_MOUSEUP => ::ElementState::Released,
+                    _ => unreachable!(),
+                };
+                queue.borrow_mut().push_back(::Event::WindowEvent {
+                    window_id: ::WindowId(WindowId(0)),
+                    event: ::WindowEvent::MouseInput {
+                        device_id: ::DeviceId(DeviceId),
+                        state,
+                        button,
+                    }
+                })
+            },
+            _ => {
+            }
+        }
+    }
+    ffi::EM_FALSE
+}
+
 extern "C" fn keyboard_callback(
     event_type: c_int,
     event: *const ffi::EmscriptenKeyboardEvent,
@@ -177,6 +230,14 @@ extern "C" fn keyboard_callback(
 {
     unsafe {
         let queue: &RefCell<VecDeque<::Event>> = mem::transmute(event_queue);
+
+        let modifiers = ::ModifiersState {
+            shift: (*event).shiftKey == ffi::EM_TRUE,
+            ctrl: (*event).ctrlKey == ffi::EM_TRUE,
+            alt: (*event).altKey == ffi::EM_TRUE,
+            logo: (*event).metaKey == ffi::EM_TRUE,
+        };
+
         match event_type {
             ffi::EMSCRIPTEN_EVENT_KEYDOWN => {
                 queue.borrow_mut().push_back(::Event::WindowEvent {
@@ -187,8 +248,8 @@ extern "C" fn keyboard_callback(
                             scancode: key_translate((*event).key) as u32,
                             state: ::ElementState::Pressed,
                             virtual_keycode: key_translate_virt((*event).key, (*event).location),
-                            modifiers: ::ModifiersState::default()        // TODO:
+                            modifiers,
-                        },   
+                        },
                     },
                 });
             },
@@ -201,7 +262,7 @@ extern "C" fn keyboard_callback(
                             scancode: key_translate((*event).key) as u32,
                             state: ::ElementState::Released,
                             virtual_keycode: key_translate_virt((*event).key, (*event).location),
-                            modifiers: ::ModifiersState::default()        // TODO:
+                            modifiers,
                         },
                     },
                 });
@@ -264,6 +325,12 @@ impl Window {
 
         // TODO: set up more event callbacks
         unsafe {
+            em_try(ffi::emscripten_set_mousemove_callback(DOCUMENT_NAME.as_ptr() as *const c_char, mem::transmute(&*window.window.events), ffi::EM_FALSE, Some(mouse_callback)))
+                .map_err(|e| ::CreationError::OsError(format!("emscripten error: {}", e)))?;
+            em_try(ffi::emscripten_set_mousedown_callback(DOCUMENT_NAME.as_ptr() as *const c_char, mem::transmute(&*window.window.events), ffi::EM_FALSE, Some(mouse_callback)))
+                .map_err(|e| ::CreationError::OsError(format!("emscripten error: {}", e)))?;
+            em_try(ffi::emscripten_set_mouseup_callback(DOCUMENT_NAME.as_ptr() as *const c_char, mem::transmute(&*window.window.events), ffi::EM_FALSE, Some(mouse_callback)))
+                .map_err(|e| ::CreationError::OsError(format!("emscripten error: {}", e)))?;
             em_try(ffi::emscripten_set_keydown_callback(DOCUMENT_NAME.as_ptr() as *const c_char, mem::transmute(&*window.window.events), ffi::EM_FALSE, Some(keyboard_callback)))
                 .map_err(|e| ::CreationError::OsError(format!("emscripten error: {}", e)))?;
             em_try(ffi::emscripten_set_keyup_callback(DOCUMENT_NAME.as_ptr() as *const c_char, mem::transmute(&*window.window.events), ffi::EM_FALSE, Some(keyboard_callback)))