Removed implicit glfwMakeCurrentContext.

Implicitly making the context current makes sense in a
single-window API but less sense in a multi-window one.

examples/boing.c

@@ -589,11 +589,13 @@ int main( void )
        exit( EXIT_FAILURE );
    }
 
+   glfwMakeContextCurrent(window);
+   glfwSwapInterval( 1 );
+
    glfwGetWindowSize(window, &width, &height);
    reshape(window, width, height);
 
    glfwSetInputMode( window, GLFW_STICKY_KEYS, GL_TRUE );
-   glfwSwapInterval( 1 );
    glfwSetTime( 0.0 );
 
    init();

examples/gears.c

@@ -353,11 +353,13 @@ int main(int argc, char *argv[])
         exit( EXIT_FAILURE );
     }
 
+    glfwMakeContextCurrent(window);
+    glfwSwapInterval( 1 );
+
     glfwGetWindowSize(window, &width, &height);
     reshape(window, width, height);
 
     glfwSetInputMode( window, GLFW_KEY_REPEAT, GL_TRUE );
-    glfwSwapInterval( 1 );
 
     // Parse command-line options
     init(argc, argv);

examples/heightmap.c

@@ -597,10 +597,12 @@ int main(int argc, char** argv)
         free(fragment_shader_src);
         exit(EXIT_FAILURE);
     }
+
+    /* Register events callback */
     glfwSetWindowCloseCallback(window_close_callback);
     glfwSetKeyCallback(key_callback);
-    /* Register events callback */
 
+    glfwMakeContextCurrent(window);
     if (GL_TRUE != init_opengl())
     {
         fprintf(stderr, "ERROR: unable to resolve OpenGL function pointers\n");

examples/splitview.c

@@ -467,12 +467,13 @@ int main(void)
         exit(EXIT_FAILURE);
     }
 
+    // Enable vsync
+    glfwMakeContextCurrent(window);
+    glfwSwapInterval(1);
+
     glfwGetWindowSize(window, &width, &height);
     windowSizeFun(window, width, height);
 
-    // Enable vsync
-    glfwSwapInterval(1);
-
     // Enable sticky keys
     glfwSetInputMode(window, GLFW_STICKY_KEYS, GL_TRUE);
 

examples/triangle.c

@@ -30,12 +30,13 @@ int main(void)
         exit(EXIT_FAILURE);
     }
 
+    // Enable vertical sync (on cards that support it)
+    glfwMakeContextCurrent(window);
+    glfwSwapInterval(1);
+
     // Ensure we can capture the escape key being pressed below
     glfwSetInputMode(window, GLFW_STICKY_KEYS, GL_TRUE);
 
-    // Enable vertical sync (on cards that support it)
-    glfwSwapInterval(1);
-
     for (;;)
     {
         double t = glfwGetTime();

examples/wave.c

@@ -413,11 +413,12 @@ int main(int argc, char* argv[])
         exit(EXIT_FAILURE);
     }
 
+    glfwMakeContextCurrent(window);
+    glfwSwapInterval(1);
+
     glfwGetWindowSize(window, &width, &height);
     window_size_callback(window, width, height);
 
-    glfwSwapInterval(1);
-
     glfwSetInputMode(window, GLFW_KEY_REPEAT, GL_TRUE);
 
     // Initialize OpenGL