Add CreationError::OpenGlVersionNotSupported

src/api/cocoa/mod.rs

@@ -512,11 +512,11 @@ impl Window {
             },
             (_, Some((1 ... 2, _)), Some(GlProfile::Core)) |
             (_, Some((3 ... 4, _)), Some(GlProfile::Compatibility)) =>
-                return Err(CreationError::NotSupported),
+                return Err(CreationError::OpenGlVersionNotSupported),
             (_, Some((1 ... 2, _)), _) => NSOpenGLProfileVersionLegacy as u32,
             (_, Some((3, 0 ... 2)), _) => NSOpenGLProfileVersion3_2Core as u32,
             (_, Some((3 ... 4, _)), _) => NSOpenGLProfileVersion4_1Core as u32,
-            _ => return Err(CreationError::NotSupported),
+            _ => return Err(CreationError::OpenGlVersionNotSupported),
         };
 
         // NOTE: OS X no longer has the concept of setting individual

src/api/egl/mod.rs

@@ -68,7 +68,7 @@ impl Context {
                         } else if egl.BindAPI(ffi::egl::OPENGL_ES_API) != 0 {
                             (None, Api::OpenGlEs)
                         } else {
-                            return Err(CreationError::NotSupported);
+                            return Err(CreationError::OpenGlVersionNotSupported);
                         }
                     } else {
                         (None, Api::OpenGlEs)
@@ -77,21 +77,21 @@ impl Context {
                 GlRequest::Specific(Api::OpenGlEs, version) => {
                     if egl_version >= (1, 2) {
                         if egl.BindAPI(ffi::egl::OPENGL_ES_API) == 0 {
-                            return Err(CreationError::NotSupported);
+                            return Err(CreationError::OpenGlVersionNotSupported);
                         }
                     }
                     (Some(version), Api::OpenGlEs)
                 },
                 GlRequest::Specific(Api::OpenGl, version) => {
                     if egl_version < (1, 4) {
-                        return Err(CreationError::NotSupported);
+                        return Err(CreationError::OpenGlVersionNotSupported);
                     }
                     if egl.BindAPI(ffi::egl::OPENGL_API) == 0 {
-                        return Err(CreationError::NotSupported);
+                        return Err(CreationError::OpenGlVersionNotSupported);
                     }
                     (Some(version), Api::OpenGl)
                 },
-                GlRequest::Specific(_, _) => return Err(CreationError::NotSupported),
+                GlRequest::Specific(_, _) => return Err(CreationError::OpenGlVersionNotSupported),
                 GlRequest::GlThenGles { opengles_version, opengl_version } => {
                     if egl_version >= (1, 4) {
                         if egl.BindAPI(ffi::egl::OPENGL_API) != 0 {
@@ -99,7 +99,7 @@ impl Context {
                         } else if egl.BindAPI(ffi::egl::OPENGL_ES_API) != 0 {
                             (Some(opengles_version), Api::OpenGlEs)
                         } else {
-                            return Err(CreationError::NotSupported);
+                            return Err(CreationError::OpenGlVersionNotSupported);
                         }
                     } else {
                         (Some(opengles_version), Api::OpenGlEs)
@@ -245,7 +245,7 @@ impl<'a> ContextPrototype<'a> {
                 {
                     ctxt
                 } else {
-                    return Err(CreationError::NotSupported);
+                    return Err(CreationError::OpenGlVersionNotSupported);
                 }
 
             } else {
@@ -267,7 +267,7 @@ impl<'a> ContextPrototype<'a> {
                 {
                     ctxt
                 } else {
-                    return Err(CreationError::NotSupported);
+                    return Err(CreationError::OpenGlVersionNotSupported);
                 }
             }
         };
@@ -504,7 +504,7 @@ unsafe fn create_context(egl: &ffi::egl::Egl, display: ffi::egl::types::EGLDispl
 
     if context.is_null() {
         match egl.GetError() as u32 {
-            ffi::egl::BAD_ATTRIBUTE => return Err(CreationError::NotSupported),
+            ffi::egl::BAD_ATTRIBUTE => return Err(CreationError::OpenGlVersionNotSupported),
             e => panic!("eglCreateContext failed: 0x{:x}", e),
         }
     }

src/api/glx/mod.rs

@@ -328,6 +328,7 @@ fn create_context(glx: &ffi::glx::Glx, extra_functions: &ffi::glx_extra::Glx, ex
         };
 
         if context.is_null() {
+            // TODO: check for errors and return `OpenGlVersionNotSupported`
             return Err(CreationError::OsError(format!("GL context creation failed")));
         }
 

src/api/osmesa/mod.rs

@@ -46,6 +46,8 @@ impl OsMesaContext {
             _ => ()
         }
 
+        // TODO: check OpenGL version and return `OpenGlVersionNotSupported` if necessary
+
         Ok(OsMesaContext {
             width: dimensions.0,
             height: dimensions.1,

src/api/wgl/mod.rs

@@ -235,7 +235,7 @@ unsafe fn create_context(extra: Option<(&gl::wgl_extra::Wgl, &BuilderAttribs<'st
                         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);
+                        return Err(CreationError::OpenGlVersionNotSupported);
                     }
 
                     attributes.push(gl::wgl_extra::CONTEXT_MAJOR_VERSION_ARB as libc::c_int);
@@ -243,7 +243,7 @@ unsafe fn create_context(extra: Option<(&gl::wgl_extra::Wgl, &BuilderAttribs<'st
                     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::Specific(_, _) => return Err(CreationError::OpenGlVersionNotSupported),
                 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);

src/lib.rs

@@ -110,6 +110,7 @@ pub enum CreationError {
     OsError(String),
     NotSupported,
     RobustnessNotSupported,
+    OpenGlVersionNotSupported,
 }
 
 impl CreationError {
@@ -119,6 +120,8 @@ impl CreationError {
             CreationError::NotSupported => "Some of the requested attributes are not supported",
             CreationError::RobustnessNotSupported => "Your requested robustness, but it is \
                                                       not supported.",
+            CreationError::OpenGlVersionNotSupported => "The requested OpenGL version is not \
+                                                         supported.",
         }
     }
 }