Create reorganization

src/api/win32/init.rs

@@ -0,0 +1,586 @@
+use std::sync::atomic::AtomicBool;
+use std::sync::{Arc, Mutex};
+use std::io;
+use std::ptr;
+use std::mem;
+use std::thread;
+
+use super::callback;
+use super::Window;
+use super::MonitorID;
+use super::ContextWrapper;
+use super::WindowWrapper;
+use super::make_current_guard::CurrentContextGuard;
+
+use Api;
+use BuilderAttribs;
+use CreationError;
+use CreationError::OsError;
+use CursorState;
+use GlRequest;
+use PixelFormat;
+
+use std::ffi::{CStr, CString, OsStr};
+use std::os::windows::ffi::OsStrExt;
+use std::sync::mpsc::channel;
+
+use libc;
+use super::gl;
+use winapi;
+use kernel32;
+use user32;
+use gdi32;
+
+/// Work-around the fact that HGLRC doesn't implement Send
+pub struct ContextHack(pub winapi::HGLRC);
+unsafe impl Send for ContextHack {}
+
+pub fn new_window(builder: BuilderAttribs<'static>, builder_sharelists: Option<ContextHack>)
+                  -> Result<Window, CreationError>
+{
+    // initializing variables to be sent to the task
+
+    let title = OsStr::new(&builder.title).encode_wide().chain(Some(0).into_iter())
+                                          .collect::<Vec<_>>();
+
+    let (tx, rx) = channel();
+
+    // `GetMessage` must be called in the same thread as CreateWindow, so we create a new thread
+    // dedicated to this window.
+    thread::spawn(move || {
+        unsafe {
+            // creating and sending the `Window`
+            match init(title, builder, builder_sharelists) {
+                Ok(w) => tx.send(Ok(w)).ok(),
+                Err(e) => {
+                    tx.send(Err(e)).ok();
+                    return;
+                }
+            };
+
+            // now that the `Window` struct is initialized, the main `Window::new()` function will
+            //  return and this events loop will run in parallel
+            loop {
+                let mut msg = mem::uninitialized();
+
+                if user32::GetMessageW(&mut msg, ptr::null_mut(), 0, 0) == 0 {
+                    break;
+                }
+
+                user32::TranslateMessage(&msg);
+                user32::DispatchMessageW(&msg);   // calls `callback` (see the callback module)
+            }
+        }
+    });
+
+    rx.recv().unwrap()
+}
+
+unsafe fn init(title: Vec<u16>, builder: BuilderAttribs<'static>,
+               builder_sharelists: Option<ContextHack>) -> Result<Window, CreationError>
+{
+    let builder_sharelists = builder_sharelists.map(|s| s.0);
+
+    // registering the window class
+    let class_name = register_window_class();
+
+    // building a RECT object with coordinates
+    let mut rect = winapi::RECT {
+        left: 0, right: builder.dimensions.unwrap_or((1024, 768)).0 as winapi::LONG,
+        top: 0, bottom: builder.dimensions.unwrap_or((1024, 768)).1 as winapi::LONG,
+    };
+
+    // switching to fullscreen if necessary
+    // this means adjusting the window's position so that it overlaps the right monitor,
+    //  and change the monitor's resolution if necessary
+    if builder.monitor.is_some() {
+        let monitor = builder.monitor.as_ref().unwrap();
+        try!(switch_to_fullscreen(&mut rect, monitor));
+    }
+
+    // computing the style and extended style of the window
+    let (ex_style, style) = if builder.monitor.is_some() {
+        (winapi::WS_EX_APPWINDOW, winapi::WS_POPUP | winapi::WS_CLIPSIBLINGS | winapi::WS_CLIPCHILDREN)
+    } else {
+        (winapi::WS_EX_APPWINDOW | winapi::WS_EX_WINDOWEDGE,
+            winapi::WS_OVERLAPPEDWINDOW | winapi::WS_CLIPSIBLINGS | winapi::WS_CLIPCHILDREN)
+    };
+
+    // adjusting the window coordinates using the style
+    user32::AdjustWindowRectEx(&mut rect, style, 0, ex_style);
+
+    // the first step is to create a dummy window and a dummy context which we will use
+    // to load the pointers to some functions in the OpenGL driver in `extra_functions`
+    let extra_functions = {
+        // creating a dummy invisible window
+        let dummy_window = {
+            let handle = user32::CreateWindowExW(ex_style, class_name.as_ptr(),
+                title.as_ptr() as winapi::LPCWSTR,
+                style | winapi::WS_CLIPSIBLINGS | winapi::WS_CLIPCHILDREN,
+                winapi::CW_USEDEFAULT, winapi::CW_USEDEFAULT,
+                rect.right - rect.left, rect.bottom - rect.top,
+                ptr::null_mut(), ptr::null_mut(), kernel32::GetModuleHandleW(ptr::null()),
+                ptr::null_mut());
+
+            if handle.is_null() {
+                return Err(OsError(format!("CreateWindowEx function failed: {}",
+                                           format!("{}", io::Error::last_os_error()))));
+            }
+
+            let hdc = user32::GetDC(handle);
+            if hdc.is_null() {
+                let err = Err(OsError(format!("GetDC function failed: {}",
+                                              format!("{}", io::Error::last_os_error()))));
+                return err;
+            }
+
+            WindowWrapper(handle, hdc)
+        };
+
+        // getting the pixel format that we will use and setting it
+        {
+            let formats = enumerate_native_pixel_formats(&dummy_window);
+            let id = try!(choose_dummy_pixel_format(formats.into_iter()));
+            try!(set_pixel_format(&dummy_window, id));
+        }
+
+        // creating the dummy OpenGL context and making it current
+        let dummy_context = try!(create_context(None, &dummy_window, None));
+        let current_context = try!(CurrentContextGuard::make_current(&dummy_window,
+                                                                     &dummy_context));
+
+        // loading the extra WGL functions
+        gl::wgl_extra::Wgl::load_with(|addr| {
+            use libc;
+
+            let addr = CString::new(addr.as_bytes()).unwrap();
+            let addr = addr.as_ptr();
+
+            gl::wgl::GetProcAddress(addr) as *const libc::c_void
+        })
+    };
+
+    // creating the real window this time, by using the functions in `extra_functions`
+    let real_window = {
+        let (width, height) = if builder.monitor.is_some() || builder.dimensions.is_some() {
+            (Some(rect.right - rect.left), Some(rect.bottom - rect.top))
+        } else {
+            (None, None)
+        };
+
+        let (x, y) = if builder.monitor.is_some() {
+            (Some(rect.left), Some(rect.top))
+        } else {
+            (None, None)
+        };
+
+        let style = if !builder.visible || builder.headless {
+            style
+        } else {
+            style | winapi::WS_VISIBLE
+        };
+
+        let handle = user32::CreateWindowExW(ex_style, class_name.as_ptr(),
+            title.as_ptr() as winapi::LPCWSTR,
+            style | winapi::WS_CLIPSIBLINGS | winapi::WS_CLIPCHILDREN,
+            x.unwrap_or(winapi::CW_USEDEFAULT), y.unwrap_or(winapi::CW_USEDEFAULT),
+            width.unwrap_or(winapi::CW_USEDEFAULT), height.unwrap_or(winapi::CW_USEDEFAULT),
+            ptr::null_mut(), ptr::null_mut(), kernel32::GetModuleHandleW(ptr::null()),
+            ptr::null_mut());
+
+        if handle.is_null() {
+            return Err(OsError(format!("CreateWindowEx function failed: {}",
+                                       format!("{}", io::Error::last_os_error()))));
+        }
+
+        let hdc = user32::GetDC(handle);
+        if hdc.is_null() {
+            return Err(OsError(format!("GetDC function failed: {}",
+                                       format!("{}", io::Error::last_os_error()))));
+        }
+
+        WindowWrapper(handle, hdc)
+    };
+
+    // calling SetPixelFormat
+    let pixel_format = {
+        let formats = if extra_functions.GetPixelFormatAttribivARB.is_loaded() {
+            enumerate_arb_pixel_formats(&extra_functions, &real_window)
+        } else {
+            enumerate_native_pixel_formats(&real_window)
+        };
+
+        let (id, f) = try!(builder.choose_pixel_format(formats.into_iter().map(|(a, b)| (b, a))));
+        try!(set_pixel_format(&real_window, id));
+        f
+    };
+
+    // creating the OpenGL context
+    let context = try!(create_context(Some((&extra_functions, &builder)), &real_window,
+                                      builder_sharelists));
+
+    // calling SetForegroundWindow if fullscreen
+    if builder.monitor.is_some() {
+        user32::SetForegroundWindow(real_window.0);
+    }
+
+    // Creating a mutex to track the current cursor state
+    let cursor_state = Arc::new(Mutex::new(CursorState::Normal));
+
+    // filling the CONTEXT_STASH task-local storage so that we can start receiving events
+    let events_receiver = {
+        let (tx, rx) = channel();
+        let mut tx = Some(tx);
+        callback::CONTEXT_STASH.with(|context_stash| {
+            let data = callback::ThreadLocalData {
+                win: real_window.0,
+                sender: tx.take().unwrap(),
+                cursor_state: cursor_state.clone()
+            };
+            (*context_stash.borrow_mut()) = Some(data);
+        });
+        rx
+    };
+
+    // loading the opengl32 module
+    let gl_library = try!(load_opengl32_dll());
+
+    // handling vsync
+    if builder.vsync {
+        if extra_functions.SwapIntervalEXT.is_loaded() {
+            let _guard = try!(CurrentContextGuard::make_current(&real_window, &context));
+
+            if extra_functions.SwapIntervalEXT(1) == 0 {
+                return Err(OsError(format!("wglSwapIntervalEXT failed")));
+            }
+        }
+    }
+
+    // building the struct
+    Ok(Window {
+        window: real_window,
+        context: context,
+        gl_library: gl_library,
+        events_receiver: events_receiver,
+        is_closed: AtomicBool::new(false),
+        cursor_state: cursor_state,
+        pixel_format: pixel_format,
+    })
+}
+
+unsafe fn register_window_class() -> Vec<u16> {
+    let class_name = OsStr::new("Window Class").encode_wide().chain(Some(0).into_iter())
+                                               .collect::<Vec<_>>();
+    
+    let class = winapi::WNDCLASSEXW {
+        cbSize: mem::size_of::<winapi::WNDCLASSEXW>() as winapi::UINT,
+        style: winapi::CS_HREDRAW | winapi::CS_VREDRAW | winapi::CS_OWNDC,
+        lpfnWndProc: Some(callback::callback),
+        cbClsExtra: 0,
+        cbWndExtra: 0,
+        hInstance: kernel32::GetModuleHandleW(ptr::null()),
+        hIcon: ptr::null_mut(),
+        hCursor: ptr::null_mut(),       // must be null in order for cursor state to work properly
+        hbrBackground: ptr::null_mut(),
+        lpszMenuName: ptr::null(),
+        lpszClassName: class_name.as_ptr(),
+        hIconSm: ptr::null_mut(),
+    };
+
+    // We ignore errors because registering the same window class twice would trigger
+    //  an error, and because errors here are detected during CreateWindowEx anyway.
+    // Also since there is no weird element in the struct, there is no reason for this
+    //  call to fail.
+    user32::RegisterClassExW(&class);
+
+    class_name
+}
+
+unsafe fn switch_to_fullscreen(rect: &mut winapi::RECT, monitor: &MonitorID)
+                               -> Result<(), CreationError>
+{
+    // adjusting the rect
+    {
+        let pos = monitor.get_position();
+        rect.left += pos.0 as winapi::LONG;
+        rect.right += pos.0 as winapi::LONG;
+        rect.top += pos.1 as winapi::LONG;
+        rect.bottom += pos.1 as winapi::LONG;
+    }
+
+    // changing device settings
+    let mut screen_settings: winapi::DEVMODEW = mem::zeroed();
+    screen_settings.dmSize = mem::size_of::<winapi::DEVMODEW>() as winapi::WORD;
+    screen_settings.dmPelsWidth = (rect.right - rect.left) as winapi::DWORD;
+    screen_settings.dmPelsHeight = (rect.bottom - rect.top) as winapi::DWORD;
+    screen_settings.dmBitsPerPel = 32;      // TODO: ?
+    screen_settings.dmFields = winapi::DM_BITSPERPEL | winapi::DM_PELSWIDTH | winapi::DM_PELSHEIGHT;
+
+    let result = user32::ChangeDisplaySettingsExW(monitor.get_adapter_name().as_ptr(),
+                                                  &mut screen_settings, ptr::null_mut(),
+                                                  winapi::CDS_FULLSCREEN, ptr::null_mut());
+    
+    if result != winapi::DISP_CHANGE_SUCCESSFUL {
+        return Err(OsError(format!("ChangeDisplaySettings failed: {}", result)));
+    }
+
+    Ok(())
+}
+
+unsafe fn create_context(extra: Option<(&gl::wgl_extra::Wgl, &BuilderAttribs<'static>)>,
+                         hdc: &WindowWrapper, share: Option<winapi::HGLRC>)
+                         -> Result<ContextWrapper, CreationError>
+{
+    let share = share.unwrap_or(ptr::null_mut());
+
+    let ctxt = if let Some((extra_functions, builder)) = extra {
+        if extra_functions.CreateContextAttribsARB.is_loaded() {
+            let mut attributes = Vec::new();
+
+            match builder.gl_version {
+                GlRequest::Latest => {},
+                GlRequest::Specific(Api::OpenGl, (major, minor)) => {
+                    attributes.push(gl::wgl_extra::CONTEXT_MAJOR_VERSION_ARB as libc::c_int);
+                    attributes.push(major as libc::c_int);
+                    attributes.push(gl::wgl_extra::CONTEXT_MINOR_VERSION_ARB as libc::c_int);
+                    attributes.push(minor as libc::c_int);
+                },
+                GlRequest::Specific(Api::OpenGlEs, (major, minor)) => {
+                    if is_extension_supported(extra_functions, hdc,
+                                              "WGL_EXT_create_context_es2_profile")
+                    {
+                        attributes.push(gl::wgl_extra::CONTEXT_PROFILE_MASK_ARB as libc::c_int);
+                        attributes.push(gl::wgl_extra::CONTEXT_ES2_PROFILE_BIT_EXT as libc::c_int);
+                    } else {
+                        return Err(CreationError::NotSupported);
+                    }
+
+                    attributes.push(gl::wgl_extra::CONTEXT_MAJOR_VERSION_ARB as libc::c_int);
+                    attributes.push(major as libc::c_int);
+                    attributes.push(gl::wgl_extra::CONTEXT_MINOR_VERSION_ARB as libc::c_int);
+                    attributes.push(minor as libc::c_int);
+                },
+                GlRequest::Specific(_, _) => return Err(CreationError::NotSupported),
+                GlRequest::GlThenGles { opengl_version: (major, minor), .. } => {
+                    attributes.push(gl::wgl_extra::CONTEXT_MAJOR_VERSION_ARB as libc::c_int);
+                    attributes.push(major as libc::c_int);
+                    attributes.push(gl::wgl_extra::CONTEXT_MINOR_VERSION_ARB as libc::c_int);
+                    attributes.push(minor as libc::c_int);
+                },
+            }
+
+            if builder.gl_debug {
+                attributes.push(gl::wgl_extra::CONTEXT_FLAGS_ARB as libc::c_int);
+                attributes.push(gl::wgl_extra::CONTEXT_DEBUG_BIT_ARB as libc::c_int);
+            }
+
+            attributes.push(0);
+
+            Some(extra_functions.CreateContextAttribsARB(hdc.1 as *const libc::c_void,
+                                                         share as *const libc::c_void,
+                                                         attributes.as_ptr()))
+
+        } else {
+            None
+        }
+    } else {
+        None
+    };
+
+    let ctxt = match ctxt {
+        Some(ctxt) => ctxt,
+        None => {
+            let ctxt = gl::wgl::CreateContext(hdc.1 as *const libc::c_void);
+            if !ctxt.is_null() && !share.is_null() {
+                gl::wgl::ShareLists(share as *const libc::c_void, ctxt);
+            };
+            ctxt
+        }
+    };
+
+    if ctxt.is_null() {
+        return Err(OsError(format!("OpenGL context creation failed: {}",
+                           format!("{}", io::Error::last_os_error()))));
+    }
+
+    Ok(ContextWrapper(ctxt as winapi::HGLRC))
+}
+
+unsafe fn enumerate_native_pixel_formats(hdc: &WindowWrapper) -> Vec<(PixelFormat, libc::c_int)> {
+    let size_of_pxfmtdescr = mem::size_of::<winapi::PIXELFORMATDESCRIPTOR>() as u32;
+    let num = gdi32::DescribePixelFormat(hdc.1, 1, size_of_pxfmtdescr, ptr::null_mut());
+
+    let mut result = Vec::new();
+
+    for index in (0 .. num) {
+        let mut output: winapi::PIXELFORMATDESCRIPTOR = mem::zeroed();
+        
+        if gdi32::DescribePixelFormat(hdc.1, index, size_of_pxfmtdescr, &mut output) == 0 {
+            continue;
+        }
+
+        if (output.dwFlags & winapi::PFD_DRAW_TO_WINDOW) == 0 {
+            continue;
+        }
+
+        if (output.dwFlags & winapi::PFD_SUPPORT_OPENGL) == 0 {
+            continue;
+        }
+
+        if output.iPixelType != winapi::PFD_TYPE_RGBA {
+            continue;
+        }
+
+        result.push((PixelFormat {
+            hardware_accelerated: (output.dwFlags & winapi::PFD_GENERIC_FORMAT) == 0,
+            red_bits: output.cRedBits,
+            green_bits: output.cGreenBits,
+            blue_bits: output.cBlueBits,
+            alpha_bits: output.cAlphaBits,
+            depth_bits: output.cDepthBits,
+            stencil_bits: output.cStencilBits,
+            stereoscopy: (output.dwFlags & winapi::PFD_STEREO) != 0,
+            double_buffer: (output.dwFlags & winapi::PFD_DOUBLEBUFFER) != 0,
+            multisampling: None,
+            srgb: false,
+        }, index));
+    }
+
+    result
+}
+
+unsafe fn enumerate_arb_pixel_formats(extra: &gl::wgl_extra::Wgl, hdc: &WindowWrapper)
+                                      -> Vec<(PixelFormat, libc::c_int)>
+{
+    let get_info = |index: u32, attrib: u32| {
+        let mut value = mem::uninitialized();
+        extra.GetPixelFormatAttribivARB(hdc.1 as *const libc::c_void, index as libc::c_int,
+                                        0, 1, [attrib as libc::c_int].as_ptr(),
+                                        &mut value);
+        value as u32
+    };
+
+    // getting the number of formats
+    // the `1` is ignored
+    let num = get_info(1, gl::wgl_extra::NUMBER_PIXEL_FORMATS_ARB);
+
+    let mut result = Vec::new();
+
+    for index in (0 .. num) {
+        if get_info(index, gl::wgl_extra::DRAW_TO_WINDOW_ARB) == 0 {
+            continue;
+        }
+        if get_info(index, gl::wgl_extra::SUPPORT_OPENGL_ARB) == 0 {
+            continue;
+        }
+
+        if get_info(index, gl::wgl_extra::ACCELERATION_ARB) == gl::wgl_extra::NO_ACCELERATION_ARB {
+            continue;
+        }
+
+        if get_info(index, gl::wgl_extra::PIXEL_TYPE_ARB) != gl::wgl_extra::TYPE_RGBA_ARB {
+            continue;
+        }
+
+        result.push((PixelFormat {
+            hardware_accelerated: true,
+            red_bits: get_info(index, gl::wgl_extra::RED_BITS_ARB) as u8,
+            green_bits: get_info(index, gl::wgl_extra::GREEN_BITS_ARB) as u8,
+            blue_bits: get_info(index, gl::wgl_extra::BLUE_BITS_ARB) as u8,
+            alpha_bits: get_info(index, gl::wgl_extra::ALPHA_BITS_ARB) as u8,
+            depth_bits: get_info(index, gl::wgl_extra::DEPTH_BITS_ARB) as u8,
+            stencil_bits: get_info(index, gl::wgl_extra::STENCIL_BITS_ARB) as u8,
+            stereoscopy: get_info(index, gl::wgl_extra::STEREO_ARB) != 0,
+            double_buffer: get_info(index, gl::wgl_extra::DOUBLE_BUFFER_ARB) != 0,
+            multisampling: {
+                if is_extension_supported(extra, hdc, "WGL_ARB_multisample") {
+                    match get_info(index, gl::wgl_extra::SAMPLES_ARB) {
+                        0 => None,
+                        a => Some(a as u16),
+                    }
+                } else {
+                    None
+                }
+            },
+            srgb: if is_extension_supported(extra, hdc, "WGL_ARB_framebuffer_sRGB") {
+                get_info(index, gl::wgl_extra::FRAMEBUFFER_SRGB_CAPABLE_ARB) != 0
+            } else if is_extension_supported(extra, hdc, "WGL_EXT_framebuffer_sRGB") {
+                get_info(index, gl::wgl_extra::FRAMEBUFFER_SRGB_CAPABLE_EXT) != 0
+            } else {
+                false
+            },
+        }, index as libc::c_int));
+    }
+
+    result
+}
+
+unsafe fn set_pixel_format(hdc: &WindowWrapper, id: libc::c_int) -> Result<(), CreationError> {
+    let mut output: winapi::PIXELFORMATDESCRIPTOR = mem::zeroed();
+
+    if gdi32::DescribePixelFormat(hdc.1, id, mem::size_of::<winapi::PIXELFORMATDESCRIPTOR>()
+                                  as winapi::UINT, &mut output) == 0
+    {
+        return Err(OsError(format!("DescribePixelFormat function failed: {}",
+                                   format!("{}", io::Error::last_os_error()))));
+    }
+
+    if gdi32::SetPixelFormat(hdc.1, id, &output) == 0 {
+        return Err(OsError(format!("SetPixelFormat function failed: {}",
+                                   format!("{}", io::Error::last_os_error()))));
+    }
+
+    Ok(())
+}
+
+unsafe fn load_opengl32_dll() -> Result<winapi::HMODULE, CreationError> {
+    let name = OsStr::new("opengl32.dll").encode_wide().chain(Some(0).into_iter())
+                                         .collect::<Vec<_>>();
+
+    let lib = kernel32::LoadLibraryW(name.as_ptr());
+
+    if lib.is_null() {
+        return Err(OsError(format!("LoadLibrary function failed: {}",
+                                    format!("{}", io::Error::last_os_error()))));
+    }
+
+    Ok(lib)
+}
+
+unsafe fn is_extension_supported(extra: &gl::wgl_extra::Wgl, hdc: &WindowWrapper,
+                                 extension: &str) -> bool
+{
+    let extensions = if extra.GetExtensionsStringARB.is_loaded() {
+        let data = extra.GetExtensionsStringARB(hdc.1 as *const _);
+        let data = CStr::from_ptr(data).to_bytes().to_vec();
+        String::from_utf8(data).unwrap()
+
+    } else if extra.GetExtensionsStringEXT.is_loaded() {
+        let data = extra.GetExtensionsStringEXT();
+        let data = CStr::from_ptr(data).to_bytes().to_vec();
+        String::from_utf8(data).unwrap()
+
+    } else {
+        return false;
+    };
+
+    extensions.split(" ").find(|&e| e == extension).is_some()
+}
+
+fn choose_dummy_pixel_format<I>(iter: I) -> Result<libc::c_int, CreationError>
+                                where I: Iterator<Item=(PixelFormat, libc::c_int)>
+{
+    let mut backup_id = None;
+
+    for (format, id) in iter {
+        if backup_id.is_none() {
+            backup_id = Some(id);
+        }
+
+        if format.hardware_accelerated {
+            return Ok(id);
+        }
+    }
+
+    backup_id.ok_or(CreationError::NotSupported)
+}