1 files changed, 99 insertions, 0 deletions
diff --git a/src/headless.rs b/src/headless.rs
new file mode 100644
index 0000000..9d9cd8d
--- /dev/null
+++ b/src/headless.rs
@@ -0,0 +1,99 @@
+use Api;
+use BuilderAttribs;
+use CreationError;
+
+use gl_common;
+use libc;
+
+use winimpl;
+
+/// Object that allows you to build headless contexts.
+pub struct HeadlessRendererBuilder {
+    attribs: BuilderAttribs<'static>,
+}
+
+impl HeadlessRendererBuilder {
+    /// Initializes a new `HeadlessRendererBuilder` with default values.
+    pub fn new(width: u32, height: u32) -> HeadlessRendererBuilder {
+        HeadlessRendererBuilder {
+            attribs: BuilderAttribs {
+                headless: true,
+                dimensions: Some((width, height)),
+                .. BuilderAttribs::new()
+            },
+        }
+    }
+
+    /// Requests to use a specific OpenGL version.
+    ///
+    /// Version is a (major, minor) pair. For example to request OpenGL 3.3
+    ///  you would pass `(3, 3)`.
+    pub fn with_gl_version(mut self, version: (u32, u32)) -> HeadlessRendererBuilder {
+        self.attribs.gl_version = Some(version);
+        self
+    }
+
+    /// Sets the *debug* flag for the OpenGL context.
+    ///
+    /// The default value for this flag is `cfg!(ndebug)`, which means that it's enabled
+    /// when you run `cargo build` and disabled when you run `cargo build --release`.
+    pub fn with_gl_debug_flag(mut self, flag: bool) -> HeadlessRendererBuilder {
+        self.attribs.gl_debug = flag;
+        self
+    }
+
+    /// Builds the headless context.
+    ///
+    /// Error should be very rare and only occur in case of permission denied, incompatible system,
+    ///  out of memory, etc.
+    pub fn build(self) -> Result<HeadlessContext, CreationError> {
+        winimpl::HeadlessContext::new(self.attribs).map(|w| HeadlessContext { context: w })
+    }
+
+    /// Builds the headless context.
+    ///
+    /// The context is build in a *strict* way. That means that if the backend couldn't give
+    /// you what you requested, an `Err` will be returned.
+    pub fn build_strict(mut self) -> Result<HeadlessContext, CreationError> {
+        self.attribs.strict = true;
+        self.build()
+    }
+}
+
+/// Represents a headless OpenGL context.
+pub struct HeadlessContext {
+    context: winimpl::HeadlessContext,
+}
+
+impl HeadlessContext {
+    /// Creates a new OpenGL context
+    /// Sets the context as the current context.
+    #[inline]
+    pub unsafe fn make_current(&self) {
+        self.context.make_current()
+    }
+
+    /// Returns the address of an OpenGL function.
+    ///
+    /// Contrary to `wglGetProcAddress`, all available OpenGL functions return an address.
+    #[inline]
+    pub fn get_proc_address(&self, addr: &str) -> *const libc::c_void {
+        self.context.get_proc_address(addr) as *const libc::c_void
+    }
+
+    /// Returns the API that is currently provided by this window.
+    ///
+    /// See `Window::get_api` for more infos.
+    pub fn get_api(&self) -> Api {
+        self.context.get_api()
+    }
+
+    pub fn set_window_resize_callback(&mut self, _: Option<fn(u32, u32)>) {
+    }
+}
+
+impl gl_common::GlFunctionsSource for HeadlessContext {
+    fn get_proc_addr(&self, addr: &str) -> *const libc::c_void {
+        self.get_proc_address(addr)
+    }
+}