kc3-lang/SDL

diff --git a/VisualC/tests/testgles2/testgles2.vcxproj b/VisualC/tests/testgles2/testgles2.vcxproj
index 186f6af..f1c633a 100644
--- a/VisualC/tests/testgles2/testgles2.vcxproj
+++ b/VisualC/tests/testgles2/testgles2.vcxproj
@@ -189,6 +189,12 @@
       <CopyLocalSatelliteAssemblies>false</CopyLocalSatelliteAssemblies>
       <ReferenceOutputAssembly>true</ReferenceOutputAssembly>
     </ProjectReference>
+    <ProjectReference Include="..\..\SDLtest\SDLtest.vcxproj">
+      <Project>{da956fd3-e143-46f2-9fe5-c77bebc56b1a}</Project>
+      <Private>false</Private>
+      <CopyLocalSatelliteAssemblies>false</CopyLocalSatelliteAssemblies>
+      <ReferenceOutputAssembly>true</ReferenceOutputAssembly>
+    </ProjectReference>
   </ItemGroup>
   <ItemGroup>
     <ClCompile Include="..\..\..\test\testgles2.c" />
@@ -196,4 +202,4 @@
   <Import Project="$(VCTargetsPath)\Microsoft.Cpp.targets" />
   <ImportGroup Label="ExtensionTargets">
   </ImportGroup>
-</Project>
\ No newline at end of file
+</Project>
diff --git a/VisualC/tests/testgles2/testgles2_VS2008.vcproj b/VisualC/tests/testgles2/testgles2_VS2008.vcproj
index b70a137..efe5355 100644
--- a/VisualC/tests/testgles2/testgles2_VS2008.vcproj
+++ b/VisualC/tests/testgles2/testgles2_VS2008.vcproj
@@ -336,6 +336,10 @@
 			CopyLocalSatelliteAssemblies="false"
 			RelativePathToProject=".\SDLmain\SDLmain_VS2008.vcproj"
 		/>
+		<ProjectReference
+			ReferencedProjectIdentifier="{DA956FD3-E143-46F2-9FE5-C77BEBC56B1A}"
+			RelativePathToProject=".\SDLtest\SDLtest_VS2008.vcproj"
+		/>
 	</References>
 	<Files>
 		<File
diff --git a/include/SDL_hints.h b/include/SDL_hints.h
index 63e507b..928aaaf 100644
--- a/include/SDL_hints.h
+++ b/include/SDL_hints.h
@@ -745,6 +745,37 @@ extern "C" {
 #define SDL_HINT_RPI_VIDEO_LAYER           "SDL_RPI_VIDEO_LAYER"
 
 /**
+ *  \brief  A variable controlling what driver to use for OpenGL ES contexts.
+ *
+ *  On some platforms, currently Windows and X11, OpenGL drivers may support
+ *  creating contexts with an OpenGL ES profile. By default SDL uses these
+ *  profiles, when available, otherwise it attempts to load an OpenGL ES
+ *  library, e.g. that provided by the ANGLE project. This variable controls
+ *  whether SDL follows this default behaviour or will always load an
+ *  OpenGL ES library.
+ *
+ *  Circumstances where this is useful include
+ *  - Testing an app with a particular OpenGL ES implementation, e.g ANGLE,
+ *    or emulator, e.g. those from ARM, Imagination or Qualcomm.
+ *  - Resolving OpenGL ES function addresses at link time by linking with
+ *    the OpenGL ES library instead of querying them at run time with
+ *    SDL_GL_GetProcAddress.
+ *
+ *  Caution: for an application to work with the default behaviour across
+ *  different OpenGL drivers it \i must query the OpenGL ES function
+ *  addresses at run time using SDL_GL_GetProcAddress.
+ *
+ *  This variable is ignored on most platforms because OpenGL ES is native
+ *  or not supported.
+ *
+ *  This variable can be set to the following values:
+ *    "0"       - Use ES profile of OpenGL, if available. (Default when not set.)
+ *    "1"       - Load OpenGL ES library using the default library names.
+ *
+ */
+#define SDL_HINT_OPENGL_ES_DRIVER   "SDL_OPENGL_ES_DRIVER"
+
+/**
  *  \brief  An enumeration of hint priorities
  */
 typedef enum
diff --git a/src/video/SDL_sysvideo.h b/src/video/SDL_sysvideo.h
index 7dc44c2..2778490 100644
--- a/src/video/SDL_sysvideo.h
+++ b/src/video/SDL_sysvideo.h
@@ -426,6 +426,8 @@ extern SDL_bool SDL_AddDisplayMode(SDL_VideoDisplay *display, const SDL_DisplayM
 extern SDL_VideoDisplay *SDL_GetDisplayForWindow(SDL_Window *window);
 extern void *SDL_GetDisplayDriverData( int displayIndex );
 
+extern void SDL_GL_DeduceMaxSupportedESProfile(int* major, int* minor);
+
 extern int SDL_RecreateWindow(SDL_Window * window, Uint32 flags);
 
 extern void SDL_OnWindowShown(SDL_Window * window);
diff --git a/src/video/SDL_video.c b/src/video/SDL_video.c
index 4738543..59d8e18 100644
--- a/src/video/SDL_video.c
+++ b/src/video/SDL_video.c
@@ -2886,6 +2886,37 @@ SDL_GL_ExtensionSupported(const char *extension)
 #endif
 }
 
+/* Deduce supported ES profile versions from the supported
+   ARB_ES*_compatibility extensions. There is no direct query.
+   
+   This is normally only called when the OpenGL driver supports
+   {GLX,WGL}_EXT_create_context_es2_profile.
+ */
+void
+SDL_GL_DeduceMaxSupportedESProfile(int* major, int* minor)
+{
+#if SDL_VIDEO_OPENGL || SDL_VIDEO_OPENGL_ES || SDL_VIDEO_OPENGL_ES2
+	/* XXX This is fragile; it will break in the event of release of
+	 * new versions of OpenGL ES.
+     */
+    if (SDL_GL_ExtensionSupported("GL_ARB_ES3_2_compatibility")) {
+        *major = 3;
+        *minor = 2;
+    } else if (SDL_GL_ExtensionSupported("GL_ARB_ES3_1_compatibility")) {
+        *major = 3;
+        *minor = 1;
+    } else if (SDL_GL_ExtensionSupported("GL_ARB_ES3_compatibility")) {
+        *major = 3;
+        *minor = 0;
+    } else {
+        *major = 2;
+        *minor = 0;
+    }
+#else
+    return SDL_FALSE;
+#endif
+}
+
 void
 SDL_GL_ResetAttributes()
 {
diff --git a/src/video/windows/SDL_windowsopengl.c b/src/video/windows/SDL_windowsopengl.c
index 3df2fe3..ffa6c2b 100644
--- a/src/video/windows/SDL_windowsopengl.c
+++ b/src/video/windows/SDL_windowsopengl.c
@@ -26,6 +26,7 @@
 #include "SDL_loadso.h"
 #include "SDL_windowsvideo.h"
 #include "SDL_windowsopengles.h"
+#include "SDL_hints.h"
 
 /* WGL implementation of SDL OpenGL support */
 
@@ -131,6 +132,44 @@ WIN_GL_LoadLibrary(_THIS, const char *path)
         return SDL_SetError("Could not retrieve OpenGL functions");
     }
 
+    /* XXX Too sleazy? WIN_GL_InitExtensions looks for certain OpenGL
+       extensions via SDL_GL_DeduceMaxSupportedESProfile. This uses
+       SDL_GL_ExtensionSupported which in turn calls SDL_GL_GetProcAddress.
+       However SDL_GL_GetProcAddress will fail if the library is not
+       loaded; it checks for gl_config.driver_loaded > 0. To avoid this
+       test failing, increment driver_loaded around the call to
+       WIN_GLInitExtensions.
+
+       Successful loading of the library is normally indicated by
+       SDL_GL_LoadLibrary incrementing driver_loaded immediately after
+       this function returns 0 to it.
+
+       Alternatives to this are:
+       - moving SDL_GL_DeduceMaxSupportedESProfile to both the WIN and
+         X11 platforms while adding a function equivalent to
+         SDL_GL_ExtensionSupported but which directly calls
+         glGetProcAddress(). Having 3 copies of the
+         SDL_GL_ExtensionSupported makes this alternative unattractive.
+       - moving SDL_GL_DeduceMaxSupportedESProfile to a new file shared
+         by the WIN and X11 platforms while adding a function equivalent
+         to SDL_GL_ExtensionSupported. This is unattractive due to the
+         number of project files that will need updating, plus there
+         will be 2 copies of the SDL_GL_ExtensionSupported code.
+       - Add a private equivalent of SDL_GL_ExtensionSupported to
+         SDL_video.c.
+       - Move the call to WIN_GL_InitExtensions back to WIN_CreateWindow
+         and add a flag to gl_data to avoid multiple calls to this
+         expensive function. This is probably the least objectionable
+         alternative if this increment/decrement trick is unacceptable.
+
+       Note that the driver_loaded > 0 check needs to remain in
+       SDL_GL_ExtensionSupported and SDL_GL_GetProcAddress as they are
+       public API functions.
+    */
+    ++_this->gl_config.driver_loaded;
+    WIN_GL_InitExtensions(_this);
+    --_this->gl_config.driver_loaded;
+
     return 0;
 }
 
@@ -407,9 +446,11 @@ WIN_GL_InitExtensions(_THIS)
     }
 
     /* Check for WGL_EXT_create_context_es2_profile */
-    _this->gl_data->HAS_WGL_EXT_create_context_es2_profile = SDL_FALSE;
     if (HasExtension("WGL_EXT_create_context_es2_profile", extensions)) {
-        _this->gl_data->HAS_WGL_EXT_create_context_es2_profile = SDL_TRUE;
+        SDL_GL_DeduceMaxSupportedESProfile(
+            &_this->gl_data->es_profile_max_supported_version.major,
+            &_this->gl_data->es_profile_max_supported_version.minor
+        );
     }
 
     /* Check for GLX_ARB_context_flush_control */
@@ -593,14 +634,26 @@ WIN_GL_SetupWindow(_THIS, SDL_Window * window)
     return retval;
 }
 
+SDL_bool
+WIN_GL_UseEGL(_THIS)
+{
+    SDL_assert(_this->gl_data != NULL);
+    SDL_assert(_this->gl_config.profile_mask == SDL_GL_CONTEXT_PROFILE_ES);
+
+    return (SDL_GetHintBoolean(SDL_HINT_OPENGL_ES_DRIVER, SDL_FALSE)
+            || _this->gl_config.major_version == 1 /* No WGL extension for OpenGL ES 1.x profiles. */
+            || _this->gl_config.major_version > _this->gl_data->es_profile_max_supported_version.major
+            || (_this->gl_config.major_version == _this->gl_data->es_profile_max_supported_version.major
+                && _this->gl_config.minor_version > _this->gl_data->es_profile_max_supported_version.minor));
+}
+
 SDL_GLContext
 WIN_GL_CreateContext(_THIS, SDL_Window * window)
 {
     HDC hdc = ((SDL_WindowData *) window->driverdata)->hdc;
     HGLRC context, share_context;
 
-    if (_this->gl_config.profile_mask == SDL_GL_CONTEXT_PROFILE_ES &&
-        !_this->gl_data->HAS_WGL_EXT_create_context_es2_profile) {
+    if (_this->gl_config.profile_mask == SDL_GL_CONTEXT_PROFILE_ES && WIN_GL_UseEGL(_this)) {
 #if SDL_VIDEO_OPENGL_EGL        
         /* Switch to EGL based functions */
         WIN_GL_UnloadLibrary(_this);
diff --git a/src/video/windows/SDL_windowsopengl.h b/src/video/windows/SDL_windowsopengl.h
index b01f96b..de0a1c7 100644
--- a/src/video/windows/SDL_windowsopengl.h
+++ b/src/video/windows/SDL_windowsopengl.h
@@ -29,10 +29,18 @@ struct SDL_GLDriverData
 {
     SDL_bool HAS_WGL_ARB_pixel_format;
     SDL_bool HAS_WGL_EXT_swap_control_tear;
-    SDL_bool HAS_WGL_EXT_create_context_es2_profile;
     SDL_bool HAS_WGL_ARB_context_flush_control;
 
-    void *(WINAPI * wglGetProcAddress) (const char *proc);
+	/* Max version of OpenGL ES context that can be created if the
+	   implementation supports WGL_EXT_create_context_es2_profile.
+	   major = minor = 0 when unsupported.
+	 */
+	struct {
+		int major;
+		int minor;
+	} es_profile_max_supported_version;
+
+	void *(WINAPI * wglGetProcAddress) (const char *proc);
       HGLRC(WINAPI * wglCreateContext) (HDC hdc);
       BOOL(WINAPI * wglDeleteContext) (HGLRC hglrc);
       BOOL(WINAPI * wglMakeCurrent) (HDC hdc, HGLRC hglrc);
@@ -56,6 +64,7 @@ struct SDL_GLDriverData
 extern int WIN_GL_LoadLibrary(_THIS, const char *path);
 extern void *WIN_GL_GetProcAddress(_THIS, const char *proc);
 extern void WIN_GL_UnloadLibrary(_THIS);
+extern SDL_bool WIN_GL_UseEGL(_THIS);
 extern int WIN_GL_SetupWindow(_THIS, SDL_Window * window);
 extern SDL_GLContext WIN_GL_CreateContext(_THIS, SDL_Window * window);
 extern int WIN_GL_MakeCurrent(_THIS, SDL_Window * window,
diff --git a/src/video/windows/SDL_windowswindow.c b/src/video/windows/SDL_windowswindow.c
index f1eeb28..531010e 100644
--- a/src/video/windows/SDL_windowswindow.c
+++ b/src/video/windows/SDL_windowswindow.c
@@ -263,6 +263,8 @@ SetupWindowData(_THIS, SDL_Window * window, HWND hwnd, SDL_bool created)
     return 0;
 }
 
+
+
 int
 WIN_CreateWindow(_THIS, SDL_Window * window)
 {
@@ -299,38 +301,36 @@ WIN_CreateWindow(_THIS, SDL_Window * window)
         return -1;
     }
 
-#if SDL_VIDEO_OPENGL_WGL
-    /* We need to initialize the extensions before deciding how to create ES profiles */
-    if (window->flags & SDL_WINDOW_OPENGL) {
-        WIN_GL_InitExtensions(_this);
+    if (!(window->flags & SDL_WINDOW_OPENGL)) {
+        return 0;
     }
-#endif
 
+    /* The rest of this macro mess is for OpenGL or OpenGL ES windows */
 #if SDL_VIDEO_OPENGL_ES2
-    if ((window->flags & SDL_WINDOW_OPENGL) &&
-        _this->gl_config.profile_mask == SDL_GL_CONTEXT_PROFILE_ES
-#if SDL_VIDEO_OPENGL_WGL           
-        && (!_this->gl_data || !_this->gl_data->HAS_WGL_EXT_create_context_es2_profile)
-#endif  
-        ) {
-#if SDL_VIDEO_OPENGL_EGL  
+    if (_this->gl_config.profile_mask == SDL_GL_CONTEXT_PROFILE_ES
+#if SDL_VIDEO_OPENGL_WGL
+        && (!_this->gl_data || WIN_GL_UseEGL(_this))
+#endif /* SDL_VIDEO_OPENGL_WGL */
+    ) {
+#if SDL_VIDEO_OPENGL_EGL
         if (WIN_GLES_SetupWindow(_this, window) < 0) {
             WIN_DestroyWindow(_this, window);
             return -1;
         }
+        return 0;
 #else
-        return SDL_SetError("Could not create GLES window surface (no EGL support available)");
-#endif /* SDL_VIDEO_OPENGL_EGL */
-    } else 
+        return SDL_SetError("Could not create GLES window surface (EGL support not configured)");
+#endif /* SDL_VIDEO_OPENGL_EGL */ 
+    }
 #endif /* SDL_VIDEO_OPENGL_ES2 */
 
 #if SDL_VIDEO_OPENGL_WGL
-    if (window->flags & SDL_WINDOW_OPENGL) {
-        if (WIN_GL_SetupWindow(_this, window) < 0) {
-            WIN_DestroyWindow(_this, window);
-            return -1;
-        }
+    if (WIN_GL_SetupWindow(_this, window) < 0) {
+        WIN_DestroyWindow(_this, window);
+        return -1;
     }
+#else
+    return SDL_SetError("Could not create GL window (WGL support not configured)");
 #endif
 
     return 0;
diff --git a/src/video/x11/SDL_x11opengl.c b/src/video/x11/SDL_x11opengl.c
index e407c29..a16bdc2 100644
--- a/src/video/x11/SDL_x11opengl.c
+++ b/src/video/x11/SDL_x11opengl.c
@@ -24,6 +24,7 @@
 
 #include "SDL_x11video.h"
 #include "SDL_assert.h"
+#include "SDL_hints.h"
 
 /* GLX implementation of SDL OpenGL support */
 
@@ -143,7 +144,6 @@ typedef GLXContext(*PFNGLXCREATECONTEXTATTRIBSARBPROC) (Display * dpy,
 
 static void X11_GL_InitExtensions(_THIS);
 
-
 int
 X11_GL_LoadLibrary(_THIS, const char *path)
 {
@@ -222,13 +222,17 @@ X11_GL_LoadLibrary(_THIS, const char *path)
     }
 
     /* Initialize extensions */
+    /* See lengthy comment about the inc/dec in 
+       ../windows/SDL_windowsopengl.c. */
+    ++_this->gl_config.driver_loaded;
     X11_GL_InitExtensions(_this);
+    --_this->gl_config.driver_loaded;
     
     /* If we need a GL ES context and there's no  
      * GLX_EXT_create_context_es2_profile extension, switch over to X11_GLES functions  
      */
     if (_this->gl_config.profile_mask == SDL_GL_CONTEXT_PROFILE_ES && 
-        ! _this->gl_data->HAS_GLX_EXT_create_context_es2_profile ) {
+        X11_GL_UseEGL(_this) ) {
 #if SDL_VIDEO_OPENGL_EGL
         X11_GL_UnloadLibrary(_this);
         /* Better avoid conflicts! */
@@ -380,7 +384,10 @@ X11_GL_InitExtensions(_THIS)
     
     /* Check for GLX_EXT_create_context_es2_profile */
     if (HasExtension("GLX_EXT_create_context_es2_profile", extensions)) {
-        _this->gl_data->HAS_GLX_EXT_create_context_es2_profile = SDL_TRUE;
+        SDL_GL_DeduceMaxSupportedESProfile(
+            &_this->gl_data->es_profile_max_supported_version.major,
+            &_this->gl_data->es_profile_max_supported_version.minor
+        );
     }
 
     /* Check for GLX_ARB_context_flush_control */
@@ -565,6 +572,19 @@ X11_GL_ErrorHandler(Display * d, XErrorEvent * e)
     return (0);
 }
 
+SDL_bool
+X11_GL_UseEGL(_THIS)
+{
+    SDL_assert(_this->gl_data != NULL);
+    SDL_assert(_this->gl_config.profile_mask == SDL_GL_CONTEXT_PROFILE_ES);
+
+    return (SDL_GetHintBoolean(SDL_HINT_OPENGL_ES_DRIVER, SDL_FALSE)
+            || _this->gl_config.major_version == 1 /* No GLX extension for OpenGL ES 1.x profiles. */
+            || _this->gl_config.major_version > _this->gl_data->es_profile_max_supported_version.major
+            || (_this->gl_config.major_version == _this->gl_data->es_profile_max_supported_version.major
+                && _this->gl_config.minor_version > _this->gl_data->es_profile_max_supported_version.minor));
+}
+
 SDL_GLContext
 X11_GL_CreateContext(_THIS, SDL_Window * window)
 {
diff --git a/src/video/x11/SDL_x11opengl.h b/src/video/x11/SDL_x11opengl.h
index 0f81e21..5d781c3 100644
--- a/src/video/x11/SDL_x11opengl.h
+++ b/src/video/x11/SDL_x11opengl.h
@@ -34,9 +34,17 @@ struct SDL_GLDriverData
     SDL_bool HAS_GLX_EXT_visual_rating;
     SDL_bool HAS_GLX_EXT_visual_info;
     SDL_bool HAS_GLX_EXT_swap_control_tear;
-    SDL_bool HAS_GLX_EXT_create_context_es2_profile;
     SDL_bool HAS_GLX_ARB_context_flush_control;
 
+	/* Max version of OpenGL ES context that can be created if the
+	   implementation supports WGL_EXT_create_context_es2_profile.
+	   major = minor = 0 when unsupported.
+	 */
+	struct {
+		int major;
+		int minor;
+	} es_profile_max_supported_version;
+
     Bool (*glXQueryExtension) (Display*,int*,int*);
     void *(*glXGetProcAddress) (const GLubyte*);
     XVisualInfo *(*glXChooseVisual) (Display*,int,int*);
@@ -57,6 +65,7 @@ struct SDL_GLDriverData
 extern int X11_GL_LoadLibrary(_THIS, const char *path);
 extern void *X11_GL_GetProcAddress(_THIS, const char *proc);
 extern void X11_GL_UnloadLibrary(_THIS);
+extern SDL_bool X11_GL_UseEGL(_THIS);
 extern XVisualInfo *X11_GL_GetVisual(_THIS, Display * display, int screen);
 extern SDL_GLContext X11_GL_CreateContext(_THIS, SDL_Window * window);
 extern int X11_GL_MakeCurrent(_THIS, SDL_Window * window,
diff --git a/src/video/x11/SDL_x11window.c b/src/video/x11/SDL_x11window.c
index a6042af..9082448 100644
--- a/src/video/x11/SDL_x11window.c
+++ b/src/video/x11/SDL_x11window.c
@@ -389,7 +389,7 @@ X11_CreateWindow(_THIS, SDL_Window * window)
 #if SDL_VIDEO_OPENGL_EGL
         if (_this->gl_config.profile_mask == SDL_GL_CONTEXT_PROFILE_ES 
 #if SDL_VIDEO_OPENGL_GLX            
-            && ( !_this->gl_data || ! _this->gl_data->HAS_GLX_EXT_create_context_es2_profile )
+            && ( !_this->gl_data || X11_GL_UseEGL(_this) )
 #endif
         ) {
             vinfo = X11_GLES_GetVisual(_this, display, screen);
@@ -600,7 +600,7 @@ X11_CreateWindow(_THIS, SDL_Window * window)
     if ((window->flags & SDL_WINDOW_OPENGL) && 
         _this->gl_config.profile_mask == SDL_GL_CONTEXT_PROFILE_ES
 #if SDL_VIDEO_OPENGL_GLX            
-        && ( !_this->gl_data || ! _this->gl_data->HAS_GLX_EXT_create_context_es2_profile )
+        && ( !_this->gl_data || X11_GL_UseEGL(_this) )
 #endif  
     ) {
 #if SDL_VIDEO_OPENGL_EGL  
@@ -617,7 +617,7 @@ X11_CreateWindow(_THIS, SDL_Window * window)
             return SDL_SetError("Could not create GLES window surface");
         }
 #else
-        return SDL_SetError("Could not create GLES window surface (no EGL support available)");
+        return SDL_SetError("Could not create GLES window surface (EGL support not configured)");
 #endif /* SDL_VIDEO_OPENGL_EGL */
     }
 #endif
diff --git a/test/testgles2.c b/test/testgles2.c
index d6261cb..58a46ac 100644
--- a/test/testgles2.c
+++ b/test/testgles2.c
@@ -20,7 +20,8 @@
 
 #include "SDL_test_common.h"
 
-#if defined(__IPHONEOS__) || defined(__ANDROID__) || defined(__EMSCRIPTEN__) || defined(__NACL__)
+#if defined(__IPHONEOS__) || defined(__ANDROID__) || defined(__EMSCRIPTEN__) || defined(__NACL__) \
+    || defined(__WINDOWS__) || defined(__LINUX__)
 #define HAVE_OPENGLES2
 #endif