Request OpenGL 3.2 rather than 3.3.

Not all 3.x drivers have the latest version, even if it is five years
old.

src/Contexts/GlxContextHandler.cpp

@@ -67,7 +67,7 @@ void GlxContextHandler::createContext(Window nativeWindow) {
     GLint attributes[] = {
         #ifndef MAGNUM_TARGET_GLES
         GLX_CONTEXT_MAJOR_VERSION_ARB, 3,
-        GLX_CONTEXT_MINOR_VERSION_ARB, 3,
+        GLX_CONTEXT_MINOR_VERSION_ARB, 2,
         GLX_CONTEXT_PROFILE_MASK_ARB, GLX_CONTEXT_CORE_PROFILE_BIT_ARB,
         #else
         GLX_CONTEXT_MAJOR_VERSION_ARB, 2,

src/Contexts/GlxContextHandler.h

@@ -32,7 +32,7 @@ namespace Magnum { namespace Contexts {
 /**
 @brief GLX interface
 
-Creates OpenGL 3.3 core context or OpenGL ES 2.0 context, if targetting
+Creates OpenGL 3.2 core context or OpenGL ES 2.0 context, if targetting
 OpenGL ES.
 
 Used in GlxWindowContext.

src/Contexts/GlxWindowContext.h

@@ -38,7 +38,7 @@ class GlxWindowContext: public AbstractXWindowContext {
          * @param title     Window title
          * @param size      Window size
          *
-         * Creates window with double-buffered OpenGL 3.3 core context or
+         * Creates window with double-buffered OpenGL 3.2 core context or
          * OpenGL ES 2.0 context, if targetting OpenGL ES.
          */
         inline GlxWindowContext(int& argc, char** argv, const std::string& title = "Magnum GLX window context", const Math::Vector2<GLsizei>& size = Math::Vector2<GLsizei>(800, 600)): AbstractXWindowContext(new GlxContextHandler, argc, argv, title, size) {}

src/Contexts/Sdl2WindowContext.cpp

@@ -26,9 +26,9 @@ Sdl2WindowContext::Sdl2WindowContext(int, char**, const std::string& name, const
         exit(1);
     }
 
-    /* Request OpenGL 3.3 */
+    /* Request OpenGL 3.2 */
     SDL_GL_SetAttribute(SDL_GL_CONTEXT_MAJOR_VERSION, 3);
-    SDL_GL_SetAttribute(SDL_GL_CONTEXT_MINOR_VERSION, 3);
+    SDL_GL_SetAttribute(SDL_GL_CONTEXT_MINOR_VERSION, 2);
 
     /* Enable double buffering and 24bt depth buffer */
     SDL_GL_SetAttribute(SDL_GL_DOUBLEBUFFER, 1);

src/Contexts/Sdl2WindowContext.h

@@ -52,7 +52,7 @@ class Sdl2WindowContext: public AbstractWindowContext {
          * @param size      Window size
          *
          * Creates centered non-resizable window with double-buffered
-         * OpenGL 3.3 context with 24bit depth buffer.
+         * OpenGL 3.2 context with 24bit depth buffer.
          */
         Sdl2WindowContext(int argc, char** argv, const std::string& title = "Magnum SDL2 window context", const Math::Vector2<GLsizei>& size = Math::Vector2<GLsizei>(800, 600));