Add support for the OpenGL debug flag

4 files changed, 39 insertions, 6 deletions

diff --git a/src/lib.rs b/src/lib.rs
index 3c8b939..d65b415 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -91,6 +91,7 @@ pub struct WindowBuilder {
     title: String,
     monitor: Option<winimpl::MonitorID>,
     gl_version: Option<(uint, uint)>,
+    gl_debug: bool,
     vsync: bool,
     visible: bool,
 }
@@ -104,6 +105,7 @@ impl WindowBuilder {
             title: "glutin window".to_string(),
             monitor: None,
             gl_version: None,
+            gl_debug: cfg!(ndebug),
             vsync: false,
             visible: true,
         }
@@ -141,6 +143,15 @@ impl WindowBuilder {
         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) -> WindowBuilder {
+        self.gl_debug = flag;
+        self
+    }
+
     /// Requests that the window has vsync enabled.
     pub fn with_vsync(mut self) -> WindowBuilder {
         self.vsync = true;
@@ -178,6 +189,7 @@ impl WindowBuilder {
 pub struct HeadlessRendererBuilder {
     dimensions: (uint, uint),
     gl_version: Option<(uint, uint)>,
+    gl_debug: bool,
 }
 
 #[cfg(feature = "headless")]
@@ -187,6 +199,7 @@ impl HeadlessRendererBuilder {
         HeadlessRendererBuilder {
             dimensions: (width, height),
             gl_version: None,
+            gl_debug: cfg!(ndebug),
         }
     }
 
@@ -199,6 +212,15 @@ impl HeadlessRendererBuilder {
         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.gl_debug = flag;
+        self
+    }
+
     /// Builds the headless context.
     ///
     /// Error should be very rare and only occur in case of permission denied, incompatible system,
diff --git a/src/win32/init.rs b/src/win32/init.rs
index 88ff069..90d6184 100644
--- a/src/win32/init.rs
+++ b/src/win32/init.rs
@@ -16,8 +16,8 @@ local_data_key!(WINDOW: (ffi::HWND, Sender<Event>))
 
 pub fn new_window(builder_dimensions: Option<(uint, uint)>, builder_title: String,
                   builder_monitor: Option<super::MonitorID>,
-                  builder_gl_version: Option<(uint, uint)>, builder_vsync: bool,
-                  builder_hidden: bool) -> Result<Window, CreationError>
+                  builder_gl_version: Option<(uint, uint)>, builder_debug: bool,
+                  builder_vsync: bool, builder_hidden: bool) -> Result<Window, CreationError>
 {
     use std::mem;
     use std::os;
@@ -298,6 +298,11 @@ pub fn new_window(builder_dimensions: Option<(uint, uint)>, builder_title: Strin
                 attributes.push(version.val1() as libc::c_int);
             }
 
+            if builder_debug {
+                attributes.push(ffi::wgl_extra::CONTEXT_FLAGS_ARB as libc::c_int);
+                attributes.push(ffi::wgl_extra::CONTEXT_DEBUG_BIT_ARB as libc::c_int);
+            }
+
             attributes.push(0);
 
             let ctxt = unsafe {
diff --git a/src/win32/mod.rs b/src/win32/mod.rs
index 282b0bb..b282385 100644
--- a/src/win32/mod.rs
+++ b/src/win32/mod.rs
@@ -24,8 +24,8 @@ pub struct HeadlessContext(Window);
 impl HeadlessContext {
     /// See the docs in the crate root file.
     pub fn new(builder: HeadlessRendererBuilder) -> Result<HeadlessContext, CreationError> {
-        let HeadlessRendererBuilder { dimensions, gl_version } = builder;
-        init::new_window(Some(dimensions), "".to_string(), None, gl_version, false, true)
+        let HeadlessRendererBuilder { dimensions, gl_version, gl_debug } = builder;
+        init::new_window(Some(dimensions), "".to_string(), None, gl_version, gl_debug, false, true)
             .map(|w| HeadlessContext(w))
     }
 
@@ -68,8 +68,9 @@ pub struct Window {
 impl Window {
     /// See the docs in the crate root file.
     pub fn new(builder: WindowBuilder) -> Result<Window, CreationError> {
-        let WindowBuilder { dimensions, title, monitor, gl_version, vsync, visible } = builder;
-        init::new_window(dimensions, title, monitor, gl_version, vsync, !visible)
+        let WindowBuilder { dimensions, title, monitor, gl_version,
+                            gl_debug, vsync, visible } = builder;
+        init::new_window(dimensions, title, monitor, gl_version, gl_debug, vsync, !visible)
     }
 }
 
diff --git a/src/x11/window/mod.rs b/src/x11/window/mod.rs
index 34d0d3b..38b4559 100644
--- a/src/x11/window/mod.rs
+++ b/src/x11/window/mod.rs
@@ -225,6 +225,11 @@ impl Window {
                 attributes.push(version.val1() as libc::c_int);
             }
 
+            if builder.gl_debug {
+                attributes.push(ffi::glx_extra::CONTEXT_FLAGS_ARB as libc::c_int);
+                attributes.push(ffi::glx_extra::CONTEXT_DEBUG_BIT_ARB as libc::c_int);
+            }
+
             attributes.push(0);
 
             // loading the extra GLX functions