In OpenGL context creation add support for compatability context.

7 files changed, 60 insertions, 27 deletions

diff --git a/src/render/modernopenglgraphics.cpp b/src/render/modernopenglgraphics.cpp
index e8d0756cf..fc5e40062 100644
--- a/src/render/modernopenglgraphics.cpp
+++ b/src/render/modernopenglgraphics.cpp
@@ -1260,7 +1260,7 @@ void ModernOpenGLGraphics::createGLContext()
     if (mGLContext)
         SDL::makeCurrentContext(mGLContext);
     else
-        mGLContext = SDL::createGLContext(mWindow, 3, 3);
+        mGLContext = SDL::createGLContext(mWindow, 3, 3, 0x01);
 }
 
 void ModernOpenGLGraphics::finalize(ImageCollection *const col)
diff --git a/src/utils/glxhelper.cpp b/src/utils/glxhelper.cpp
index bd50d8c61..e27124325 100644
--- a/src/utils/glxhelper.cpp
+++ b/src/utils/glxhelper.cpp
@@ -39,7 +39,8 @@ static int ErrorHandler(Display *d A_UNUSED, XErrorEvent *e A_UNUSED)
 void *GlxHelper::createContext(const unsigned long window,
                                void *const display0,
                                const int major,
-                               const int minor)
+                               const int minor,
+                               const int profile)
 {
     Display *const display = static_cast<Display*>(display0);
     XSync(display, false);
@@ -88,7 +89,7 @@ void *GlxHelper::createContext(const unsigned long window,
     {
         GLX_CONTEXT_MAJOR_VERSION_ARB, major,
         GLX_CONTEXT_MINOR_VERSION_ARB, minor,
-        GLX_CONTEXT_PROFILE_MASK_ARB, 0x01,   // core profile
+        GLX_CONTEXT_PROFILE_MASK_ARB, profile,
         0, 0
     };
 
diff --git a/src/utils/glxhelper.h b/src/utils/glxhelper.h
index 528e3f7fb..e76da1005 100644
--- a/src/utils/glxhelper.h
+++ b/src/utils/glxhelper.h
@@ -32,7 +32,8 @@ namespace GlxHelper
     void *createContext(const unsigned long window,
                         void *const display,
                         const int major,
-                        const int minor);
+                        const int minor,
+                        const int profile);
 
     bool makeCurrent(const unsigned long window,
                      void *const display,
diff --git a/src/utils/sdl2helper.cpp b/src/utils/sdl2helper.cpp
index 07f8d965c..6de5ef357 100644
--- a/src/utils/sdl2helper.cpp
+++ b/src/utils/sdl2helper.cpp
@@ -96,33 +96,48 @@ SDL_Thread *SDL::createThread(SDL_ThreadFunction fn,
 
 void *SDL::createGLContext(SDL_Window *const window,
                            const int major,
-                           const int minor)
+                           const int minor,
+                           const int profile)
 {
     SDL_GL_SetAttribute(SDL_GL_CONTEXT_MAJOR_VERSION, major);
     SDL_GL_SetAttribute(SDL_GL_CONTEXT_MINOR_VERSION, minor);
-    SDL_GL_SetAttribute(SDL_GL_CONTEXT_PROFILE_MASK,
-        SDL_GL_CONTEXT_PROFILE_CORE);
+    SDL_GL_SetAttribute(SDL_GL_CONTEXT_PROFILE_MASK, profile);
 //    SDL_GL_SetAttribute(SDL_GL_CONTEXT_FLAGS, SDL_GL_CONTEXT_DEBUG_FLAG);
     SDL_ClearError();
     void *context = SDL_GL_CreateContext(window);
-    if (SDL_GetError())
+    if (SDL_GetError() && (major > 3 || (major == 3 && minor > 3)))
     {
-        if (!context && (major > 3 || (major == 3 && minor > 3)))
+        logger->log("Try fallback to OpenGL 3.3 core context");
+        SDL_GL_SetAttribute(SDL_GL_CONTEXT_MAJOR_VERSION, 3);
+        SDL_GL_SetAttribute(SDL_GL_CONTEXT_MINOR_VERSION, 3);
+        SDL_ClearError();
+        context = SDL_GL_CreateContext(window);
+        if (SDL_GetError() && profile == 0x01)
         {
-            logger->log("Try fallback to OpenGL 3.3 context");
+            logger->log("Try fallback to OpenGL 3.3 compatibility context");
             SDL_GL_SetAttribute(SDL_GL_CONTEXT_MAJOR_VERSION, 3);
             SDL_GL_SetAttribute(SDL_GL_CONTEXT_MINOR_VERSION, 3);
+            SDL_GL_SetAttribute(SDL_GL_CONTEXT_PROFILE_MASK, 0x02);
             SDL_ClearError();
             context = SDL_GL_CreateContext(window);
-            if (SDL_GetError())
-            {
-                logger->log("Try fallback to OpenGL 3.0 context");
-                SDL_GL_SetAttribute(SDL_GL_CONTEXT_MAJOR_VERSION, 3);
-                SDL_GL_SetAttribute(SDL_GL_CONTEXT_MINOR_VERSION, 0);
-                context = SDL_GL_CreateContext(window);
-            }
         }
     }
+    if (SDL_GetError() && (major > 3 || (major == 3 && minor > 0)))
+    {
+        logger->log("Try fallback to OpenGL 3.0 core context");
+        SDL_GL_SetAttribute(SDL_GL_CONTEXT_MAJOR_VERSION, 3);
+        SDL_GL_SetAttribute(SDL_GL_CONTEXT_MINOR_VERSION, 0);
+        SDL_GL_SetAttribute(SDL_GL_CONTEXT_PROFILE_MASK, profile);
+        context = SDL_GL_CreateContext(window);
+    }
+    if (SDL_GetError() && (major > 2 || (major == 2 && minor > 1)))
+    {
+        logger->log("Try fallback to OpenGL 2.1 compatibility context");
+        SDL_GL_SetAttribute(SDL_GL_CONTEXT_MAJOR_VERSION, 2);
+        SDL_GL_SetAttribute(SDL_GL_CONTEXT_MINOR_VERSION, 1);
+        SDL_GL_SetAttribute(SDL_GL_CONTEXT_PROFILE_MASK, 0x02);
+        context = SDL_GL_CreateContext(window);
+    }
     return context;
 }
 
diff --git a/src/utils/sdl2helper.h b/src/utils/sdl2helper.h
index b7ab35d84..0f8f7c6ff 100644
--- a/src/utils/sdl2helper.h
+++ b/src/utils/sdl2helper.h
@@ -54,7 +54,8 @@ namespace SDL
 
     void *createGLContext(SDL_Window *const window,
                           const int major,
-                          const int minor);
+                          const int minor,
+                          const int profile);
 
     void makeCurrentContext(void *const context);
 }  // namespace SDL
diff --git a/src/utils/sdlhelper.cpp b/src/utils/sdlhelper.cpp
index b809fd76b..7604334c9 100644
--- a/src/utils/sdlhelper.cpp
+++ b/src/utils/sdlhelper.cpp
@@ -119,25 +119,38 @@ SDL_Thread *SDL::createThread(int (SDLCALL *fn)(void *),
 #if defined(USE_X11) && defined(USE_OPENGL)
 void *SDL::createGLContext(SDL_Surface *const window A_UNUSED,
                            const int major,
-                           const int minor)
+                           const int minor,
+                           const int profile)
 {
     SDL_SysWMinfo info;
     SDL_VERSION(&info.version);
     SDL_GetWMInfo(&info);
     void *context = GlxHelper::createContext(info.info.x11.window,
-        info.info.x11.display, major, minor);
+        info.info.x11.display, major, minor, profile);
     if (!context && (major > 3 || (major == 3 && minor > 3)))
     {
-        logger->log("Try fallback to OpenGL 3.3 context");
+        logger->log("Try fallback to OpenGL 3.3 core context");
         context = GlxHelper::createContext(info.info.x11.window,
-            info.info.x11.display, 3, 3);
-        if (!context)
+            info.info.x11.display, 3, 3, profile);
+        if (!context && profile == 0x01)
         {
-            logger->log("Try fallback to OpenGL 3.0 context");
+            logger->log("Try fallback to OpenGL 3.3 compatibility context");
             context = GlxHelper::createContext(info.info.x11.window,
-                info.info.x11.display, 3, 0);
+                info.info.x11.display, 3, 3, 0x02);
         }
     }
+    if (!context && (major > 3 || (major == 3 && minor > 0)))
+    {
+        logger->log("Try fallback to OpenGL 3.0 core context");
+        context = GlxHelper::createContext(info.info.x11.window,
+            info.info.x11.display, 3, 0, profile);
+    }
+    if (!context && (major > 2 || (major == 2 && minor > 1)))
+    {
+        logger->log("Try fallback to OpenGL 2.1 compatibility context");
+        context = GlxHelper::createContext(info.info.x11.window,
+            info.info.x11.display, 2, 1, 0x02);
+    }
     return context;
 }
 
@@ -153,7 +166,8 @@ void SDL::makeCurrentContext(void *const context)
 #else
 void *SDL::createGLContext(SDL_Surface *const window A_UNUSED,
                            const int major A_UNUSED,
-                           const int minor A_UNUSED)
+                           const int minor A_UNUSED,
+                           const int profile A_UNUSED)
 {
     return nullptr;
 }
diff --git a/src/utils/sdlhelper.h b/src/utils/sdlhelper.h
index 92fcaba65..36616797e 100644
--- a/src/utils/sdlhelper.h
+++ b/src/utils/sdlhelper.h
@@ -59,7 +59,8 @@ namespace SDL
 
     void *createGLContext(SDL_Surface *const window A_UNUSED,
                           const int major,
-                          const int minor);
+                          const int minor,
+                          const int profile);
 
     void makeCurrentContext(void *const context);
 }  // namespace SDL