Add manual OpenGL context creation.

For SDL2 set attributes for context version.
For SDL1.2 in X11 create own context.
For SDL1.2 and other platforms not implimented for now.

Also try fallback if need to older context versions.

8 files changed, 47 insertions, 6 deletions

diff --git a/src/render/graphics.cpp b/src/render/graphics.cpp
index 5bb90e753..5cb45e8ca 100644
--- a/src/render/graphics.cpp
+++ b/src/render/graphics.cpp
@@ -71,6 +71,8 @@
 #include "graphicsmanager.h"
 #include "logger.h"
 
+#include "render/mglxinit.h"
+
 #include "resources/imagehelper.h"
 #include "resources/openglimagehelper.h"
 
@@ -99,10 +101,10 @@ Graphics::Graphics() :
     mWindow(nullptr),
 #ifdef USE_SDL2
     mRenderer(nullptr),
+#endif
 #ifdef USE_OPENGL
     mGLContext(nullptr),
 #endif
-#endif
     mBpp(0),
     mAlpha(false),
     mFullscreen(false),
@@ -252,11 +254,15 @@ bool Graphics::setOpenGLMode()
         mActualWidth, mActualHeight,
         mBpp, getOpenGLFlags())))
     {
+        logger->log("Window/context creation failed");
         mRect.w = 0;
         mRect.h = 0;
         return false;
     }
 
+#if defined(USE_OPENGL) && defined(USE_X11)
+    Glx::initFunctions();
+#endif
 #ifdef USE_SDL2
     int w1 = 0;
     int h1 = 0;
@@ -264,10 +270,10 @@ bool Graphics::setOpenGLMode()
     mRect.w = static_cast<int32_t>(w1 / mScale);
     mRect.h = static_cast<int32_t>(h1 / mScale);
 
-    mGLContext = SDL_GL_CreateContext(mWindow);
-
+    createGLContext();
 #else  // USE_SDL2
 
+    createGLContext();
     mRect.w = static_cast<uint16_t>(mWindow->w / mScale);
     mRect.h = static_cast<uint16_t>(mWindow->h / mScale);
 
@@ -353,6 +359,14 @@ int Graphics::getSoftwareFlags() const
     return displayFlags;
 }
 
+#ifdef USE_OPENGL
+void Graphics::createGLContext()
+{
+#ifdef USE_SDL2
+    mGLContext = SDL_GL_CreateContext(mWindow);
+#endif
+}
+#endif
 
 void Graphics::updateMemoryInfo()
 {
diff --git a/src/render/graphics.h b/src/render/graphics.h
index 3100971fc..2c4bc57ec 100644
--- a/src/render/graphics.h
+++ b/src/render/graphics.h
@@ -496,6 +496,9 @@ class Graphics notfinal
 
         bool videoInfo();
 
+#ifdef USE_OPENGL
+        virtual void createGLContext();
+#endif
         /**
          * Holds the clip area stack.
          */
@@ -505,10 +508,16 @@ class Graphics notfinal
 
 #ifdef USE_SDL2
         SDL_Renderer *mRenderer;
+#endif  // USE_SDL2
 #ifdef USE_OPENGL
+#ifdef USE_SDL2
         SDL_GLContext mGLContext;
-#endif
-#endif
+#else  // USE_SDL2
+
+        void *mGLContext;
+#endif  // USE_SDL2
+#endif  // USE_OPENGL
+
         int mBpp;
         bool mAlpha;
         bool mFullscreen;
diff --git a/src/render/mglx.cpp b/src/render/mglx.cpp
index 4c51cba14..73beb959c 100644
--- a/src/render/mglx.cpp
+++ b/src/render/mglx.cpp
@@ -30,5 +30,7 @@ defName(glXCreateContext);
 defName(glXGetCurrentContext);
 defName(glXCreateContextAttribs);
 defName(glXChooseFBConfig);
+defName(glXDestroyContext);
+defName(glXMakeCurrent);
 
 #endif
diff --git a/src/render/mglx.h b/src/render/mglx.h
index ceb916b8d..2e0c93364 100644
--- a/src/render/mglx.h
+++ b/src/render/mglx.h
@@ -32,6 +32,8 @@ defNameE(glXCreateContext);
 defNameE(glXGetCurrentContext);
 defNameE(glXCreateContextAttribs);
 defNameE(glXChooseFBConfig);
+defNameE(glXDestroyContext);
+defNameE(glXMakeCurrent);
 
 #undef defNameE
 
diff --git a/src/render/mglxinit.cpp b/src/render/mglxinit.cpp
index 81035a37c..bcf9eb31e 100644
--- a/src/render/mglxinit.cpp
+++ b/src/render/mglxinit.cpp
@@ -34,6 +34,8 @@ void Glx::initFunctions()
     assignFunction(glXGetCurrentContext, "glXGetCurrentContext");
     assignFunction(glXCreateContextAttribs, "glXCreateContextAttribsARB");
     assignFunction(glXChooseFBConfig, "glXChooseFBConfig");
+    assignFunction(glXDestroyContext, "glXDestroyContext");
+    assignFunction(glXMakeCurrent, "glXMakeCurrent");
 }
 
 #endif
diff --git a/src/render/mglxtypes.h b/src/render/mglxtypes.h
index 700d62287..d8d66bdab 100644
--- a/src/render/mglxtypes.h
+++ b/src/render/mglxtypes.h
@@ -37,10 +37,13 @@
 typedef void *(*glXCreateContext_t) (Display *dpy, XVisualInfo *vis,
     void *shareList, bool direct);
 typedef void *(*glXGetCurrentContext_t) (void);
-typedef void (*glXCreateContextAttribs_t) (Display *dpy, GLXFBConfig config,
+typedef void *(*glXCreateContextAttribs_t) (Display *dpy, GLXFBConfig config,
     void *share_context, bool direct, const int *attrib_list);
 typedef GLXFBConfig *(*glXChooseFBConfig_t) (Display *dpy, int screen,
     const int *attrib_list, int *nelements);
+typedef void (*glXDestroyContext_t) (Display *dpy, void *ctx);
+typedef bool (*glXMakeCurrent_t) (Display *dpy,
+    GLXDrawable drawable, void *ctx);
 
 #endif  // USE_OPENGL
 #endif  // RENDER_MGLXTYPES_H
diff --git a/src/render/modernopenglgraphics.cpp b/src/render/modernopenglgraphics.cpp
index ce7f86f56..3595d6a78 100644
--- a/src/render/modernopenglgraphics.cpp
+++ b/src/render/modernopenglgraphics.cpp
@@ -41,6 +41,7 @@
 #include "resources/openglimagehelper.h"
 
 #include "utils/sdlcheckutils.h"
+#include "utils/sdlhelper.h"
 
 #include "debug.h"
 
@@ -1260,6 +1261,11 @@ void ModernOpenGLGraphics::clearScreen() const
     glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT | GL_STENCIL_BUFFER_BIT);
 }
 
+void ModernOpenGLGraphics::createGLContext()
+{
+    mGLContext = SDL::createGLContext(mWindow, 3, 3);
+}
+
 void ModernOpenGLGraphics::finalize(ImageCollection *const col)
 {
     FOR_EACH (ImageCollectionIter, it, col->draws)
diff --git a/src/render/modernopenglgraphics.h b/src/render/modernopenglgraphics.h
index 28a7f8bbb..2b27c621e 100644
--- a/src/render/modernopenglgraphics.h
+++ b/src/render/modernopenglgraphics.h
@@ -81,6 +81,9 @@ class ModernOpenGLGraphics final : public Graphics
 
         #include "render/openglgraphicsdefadvanced.hpp"
 
+    protected:
+        virtual void createGLContext() override final;
+
     private:
         inline void drawQuad(const Image *const image,
                              const int srcX, const int srcY,