Some comments.

common/gal/opengl/opengl_compositor.cpp

@@ -167,8 +167,9 @@ unsigned int OPENGL_COMPOSITOR::CreateBuffer()
         }
     }
 
-
     ClearBuffer();
+
+    // Return to direct rendering (we were asked only to create a buffer, not switch to one)
     glBindFramebuffer( GL_FRAMEBUFFER, DIRECT_RENDERING );
     m_currentFbo = DIRECT_RENDERING;
 

common/tool/tool_manager.cpp

@@ -207,9 +207,9 @@ void TOOL_MANAGER::dispatchInternal( TOOL_EVENT& aEvent )
 				st->wakeupEvent = aEvent;
 				st->pendingWait = false;
 				st->waitEvents.clear();
-				st->cofunc->Resume();
-				if( !st->cofunc->Running() )
+				if( !st->cofunc->Resume() )
 				{
+				    // The couroutine has finished
 				    finishTool( st );
 				}
 
@@ -258,6 +258,7 @@ void TOOL_MANAGER::finishTool( TOOL_STATE* aState )
 {
     wxASSERT( m_activeTools.front() == aState->theTool->GetId() );
 
+    // Deactivate the most recent tool and remove it from the active tools queue
     aState->idle = true;
     m_activeTools.erase( m_activeTools.begin() );
 

include/tool/tool_manager.h

@@ -154,7 +154,7 @@ public:
                               CONTEXT_MENU_TRIGGER aTrigger );
 
     /**
-     * Allows a tool pass the already handled event to be passed to the next tool on the stack.
+     * Allows a tool to pass the already handled event to the next tool on the stack.
      */
     void PassEvent()
     {