Implement access of raw context handles

src/api/android/mod.rs

@@ -23,9 +23,6 @@ pub struct Context {
     egl_context: EglContext,
 }
 
-#[derive(Clone, Default)]
-pub struct PlatformSpecificHeadlessBuilderAttributes;
-
 impl Context {
     pub fn new(
         window_builder: winit::WindowBuilder,
@@ -81,8 +78,16 @@ impl Context {
     pub fn get_pixel_format(&self) -> PixelFormat {
         self.egl_context.get_pixel_format()
     }
+
+    #[inline]
+    pub unsafe fn raw_handle(&self) -> egl::ffi::EGLContext {
+        self.egl_context.raw_handle()
+    }
 }
 
+#[derive(Clone, Default)]
+pub struct PlatformSpecificHeadlessBuilderAttributes;
+
 pub struct HeadlessContext(EglContext);
 
 unsafe impl Send for HeadlessContext {}
@@ -135,4 +140,9 @@ impl HeadlessContext {
     pub fn get_pixel_format(&self) -> PixelFormat {
         self.0.get_pixel_format()
     }
+
+    #[inline]
+    pub unsafe fn raw_handle(&self) -> egl::ffi::EGLContext {
+        self.0.raw_handle()
+    }
 }

src/api/caca/mod.rs

@@ -111,7 +111,6 @@ impl Context {
     pub fn get_pixel_format(&self) -> PixelFormat {
         self.opengl.get_pixel_format()
     }
-
 }
 
 impl Drop for Context {

src/api/egl/ffi.rs

@@ -1,10 +1,12 @@
 #![allow(non_camel_case_types)]
 
-use libc;
-
 #[cfg(target_os = "windows")]
 extern crate winapi;
 
+pub use self::egl::types::EGLContext;
+
+use libc;
+
 pub mod egl {
     pub type khronos_utime_nanoseconds_t = super::khronos_utime_nanoseconds_t;
     pub type khronos_uint64_t = super::khronos_uint64_t;

src/api/egl/mod.rs

@@ -320,6 +320,11 @@ impl Context {
     pub fn get_pixel_format(&self) -> PixelFormat {
         self.pixel_format.clone()
     }
+
+    #[inline]
+    pub unsafe fn raw_handle(&self) -> ffi::egl::types::EGLContext {
+        self.context
+    }
 }
 
 unsafe impl Send for Context {}

src/api/glx/mod.rs

@@ -143,6 +143,11 @@ impl Context {
     pub fn get_pixel_format(&self) -> PixelFormat {
         self.pixel_format.clone()
     }
+
+    #[inline]
+    pub unsafe fn raw_handle(&self) -> ffi::GLXContext {
+        self.context
+    }
 }
 
 unsafe impl Send for Context {}

src/api/ios/mod.rs

@@ -343,12 +343,10 @@ impl Window {
     }
 
     #[inline]
-    pub fn set_window_resize_callback(&mut self, _: Option<fn(u32, u32)>) {
-    }
+    pub fn set_window_resize_callback(&mut self, _: Option<fn(u32, u32)>) {}
 
     #[inline]
-    pub fn set_cursor(&self, _: MouseCursor) {
-    }
+    pub fn set_cursor(&self, _: MouseCursor) {}
 
     #[inline]
     pub fn set_cursor_state(&self, _: CursorState) -> Result<(), String> {
@@ -369,7 +367,6 @@ impl Window {
     pub fn create_window_proxy(&self) -> WindowProxy {
         WindowProxy
     }
-
 }
 
 impl GlContext for Window {
@@ -427,7 +424,6 @@ impl WindowProxy {
     }
 }
 
-
 impl<'a> Iterator for WaitEventsIterator<'a> {
     type Item = Event;
 

src/api/osmesa/mod.rs

@@ -2,11 +2,6 @@
 
 extern crate osmesa_sys;
 
-use std::error::Error;
-use std::ffi::CString;
-use std::fmt::{Debug, Display, Error as FormatError, Formatter};
-use std::{mem, ptr};
-
 use Api;
 use ContextError;
 use CreationError;
@@ -18,6 +13,16 @@ use PixelFormatRequirements;
 use Robustness;
 use libc;
 
+use std::error::Error;
+use std::ffi::CString;
+use std::fmt::{Debug, Display, Error as FormatError, Formatter};
+use std::{mem, ptr};
+use std::os::raw::c_void;
+
+pub mod ffi {
+    pub use super::osmesa_sys::OSMesaContext;
+}
+
 pub struct OsMesaContext {
     context: osmesa_sys::OSMesaContext,
     buffer: Vec<u32>,
@@ -186,6 +191,11 @@ impl OsMesaContext {
     pub fn get_pixel_format(&self) -> PixelFormat {
         unimplemented!();
     }
+
+    #[inline]
+    pub unsafe fn raw_handle(&self) -> *mut c_void {
+        self.context as *mut _
+    }
 }
 
 impl Drop for OsMesaContext {

src/api/wgl/mod.rs

@@ -16,8 +16,7 @@ use self::make_current_guard::CurrentContextGuard;
 use std::ffi::{CStr, CString, OsStr};
 use std::os::raw::{c_void, c_int};
 use std::os::windows::ffi::OsStrExt;
-use std::{mem, ptr};
-use std::io;
+use std::{io, mem, ptr};
 
 use winapi;
 use kernel32;

src/headless.rs

@@ -93,7 +93,7 @@ impl<'a> HeadlessRendererBuilder<'a> {
 
 /// Represents a headless OpenGL context.
 pub struct HeadlessContext {
-    context: platform::HeadlessContext,
+    pub(crate) context: platform::HeadlessContext,
 }
 
 impl GlContext for HeadlessContext {
@@ -142,4 +142,3 @@ impl GlContext for HeadlessContext {
         unimplemented!()
     }
 }
-

src/os/android.rs

@@ -1,3 +1,26 @@
 #![cfg(any(target_os = "android"))]
 
 pub use winit::os::android::{WindowBuilderExt, WindowExt};
+
+pub use api::egl::ffi::EGLContext;
+
+use {Context, HeadlessContext};
+use os::GlContextExt;
+
+impl GlContextExt for Context {
+    type Handle = EGLContext;
+
+    #[inline]
+    unsafe fn raw_handle(&self) -> Self::Handle {
+        self.context.raw_handle()
+    }
+}
+
+impl GlContextExt for HeadlessContext {
+    type Handle = EGLContext;
+
+    #[inline]
+    unsafe fn raw_handle(&self) -> Self::Handle {
+        self.context.raw_handle()
+    }
+}

src/os/macos.rs

@@ -4,3 +4,26 @@ pub use winit::os::macos::ActivationPolicy;
 pub use winit::os::macos::MonitorIdExt;
 pub use winit::os::macos::WindowBuilderExt;
 pub use winit::os::macos::WindowExt;
+
+use {Context, HeadlessContext};
+use os::GlContextExt;
+
+use std::os::raw::c_void;
+
+impl GlContextExt for Context {
+    type Handle = *mut c_void;
+
+    #[inline]
+    unsafe fn raw_handle(&self) -> Self::Handle {
+        self.context.raw_handle()
+    }
+}
+
+impl GlContextExt for HeadlessContext {
+    type Handle = *mut c_void;
+
+    #[inline]
+    unsafe fn raw_handle(&self) -> Self::Handle {
+        self.context.raw_handle()
+    }
+}

src/os/mod.rs

@@ -1,12 +1,23 @@
 //! Contains traits with platform-specific methods in them.
 //!
-//! Contains the follow modules:
+//! Contains the following modules:
 //!
+//!  - `android`
 //!  - `macos`
 //!  - `unix`
 //!  - `windows`
 //!
+
 pub mod android;
 pub mod macos;
 pub mod unix;
 pub mod windows;
+
+/// Platform-specific extensions for OpenGL contexts.
+pub trait GlContextExt {
+    /// Raw context handle.
+    type Handle;
+
+    /// Returns the raw context handle.
+    unsafe fn raw_handle(&self) -> Self::Handle;
+}

src/os/unix.rs

@@ -1,7 +1,34 @@
 #![cfg(any(target_os = "linux", target_os = "dragonfly", target_os = "freebsd", target_os = "openbsd"))]
 
+pub use api::egl::ffi::EGLContext;
+pub use api::glx::ffi::GLXContext;
+pub use platform::RawHandle;
+
 pub use winit::os::unix::XNotSupported;
 pub use winit::os::unix::EventsLoopExt;
 pub use winit::os::unix::MonitorIdExt;
 pub use winit::os::unix::WindowBuilderExt;
 pub use winit::os::unix::WindowExt;
+
+use {Context, HeadlessContext};
+use os::GlContextExt;
+
+use std::os::raw::c_void;
+
+impl GlContextExt for Context {
+    type Handle = RawHandle;
+
+    #[inline]
+    unsafe fn raw_handle(&self) -> Self::Handle {
+        self.context.raw_handle()
+    }
+}
+
+impl GlContextExt for HeadlessContext {
+    type Handle = *mut c_void;
+
+    #[inline]
+    unsafe fn raw_handle(&self) -> Self::Handle {
+        self.context.raw_handle()
+    }
+}

src/os/windows.rs

@@ -1,3 +1,28 @@
 #![cfg(target_os = "windows")]
 
+pub use winapi::HGLRC;
 pub use winit::os::windows::{WindowBuilderExt, WindowExt, MonitorIdExt};
+
+pub use api::egl::ffi::EGLContext;
+pub use platform::RawHandle;
+
+use {Context, HeadlessContext};
+use os::GlContextExt;
+
+impl GlContextExt for Context {
+    type Handle = RawHandle;
+
+    #[inline]
+    unsafe fn raw_handle(&self) -> Self::Handle {
+        self.context.raw_handle()
+    }
+}
+
+impl GlContextExt for HeadlessContext {
+    type Handle = RawHandle;
+
+    #[inline]
+    unsafe fn raw_handle(&self) -> Self::Handle {
+        self.context.raw_handle()
+    }
+}

src/platform/emscripten/mod.rs

@@ -1,8 +1,10 @@
 #![cfg(target_os = "emscripten")]
 
+use std::ffi::CString;
+
 use {Api, ContextError, CreationError, GlAttributes, PixelFormat, PixelFormatRequirements};
+
 use winit;
-use std::ffi::CString;
 
 mod ffi;
 
@@ -114,6 +116,11 @@ impl Context {
             srgb: true,
         }
     }
+
+    #[inline]
+    pub unsafe fn raw_handle(&self) -> ffi::EMSCRIPTEN_WEBGL_CONTEXT_HANDLE {
+        self.context
+    }
 }
 
 impl Drop for Context {
@@ -178,6 +185,11 @@ impl HeadlessContext {
     pub fn get_pixel_format(&self) -> PixelFormat {
         unimplemented!()
     }
+
+    #[inline]
+    pub unsafe fn raw_handle(&self) -> ffi::EMSCRIPTEN_WEBGL_CONTEXT_HANDLE {
+        self.context
+    }
 }
 
 fn error_to_str(code: ffi::EMSCRIPTEN_RESULT) -> &'static str {