Fix GUI bugs in FLTK port, per Xavier Thomas's forum post:

"There was some small but annoying bugs with the FLTK port:
-cursor disappear sometimes
-not all the area of the windows (graphic and text windows) is accessible
by the mouse after a re-size
-input widget for editing constraints value are not correctly placed"

src/fltk/fltkmain.cpp

@@ -359,45 +359,6 @@ int64_t GetUnixTime(void)
     return (int64_t)ret;
 }
 
-void ShowTextEditControl(int x, int y, char *s)
-{
-    if(GraphicsEditControlIsVisible()) return;
-
-    // Note: TextEditControl->position() does NOT set (x,y) position!
-    TextEditControl->resize(x, y, TextEditControl->w(), TextEditControl->h());
-    if(s) TextEditControl->value(s);
-    TextEditControl->show();
-}
-
-void HideTextEditControl(void)
-{
-    TextEditControl->hide();
-}
-
-bool TextEditControlIsVisible(void)
-{
-    return TextEditControl->visible();
-}
-
-void ShowGraphicsEditControl(int x, int y, char *s)
-{
-    if(GraphicsEditControlIsVisible()) return;
-
-    GraphicsEditControl->position(x, y);
-    GraphicsEditControl->value(s);
-    GraphicsEditControl->show();
-}
-
-void HideGraphicsEditControl(void)
-{
-    GraphicsEditControl->hide();
-}
-
-bool GraphicsEditControlIsVisible(void)
-{
-    return GraphicsEditControl->visible();
-}
-
 class Graphics_Gl_Window : public Fl_Gl_Window_Group
 {
 public:
@@ -713,6 +674,73 @@ void Text_Gl_Window::dummy(void)
     // sop to Clang++'s -Wweak-vtables warning
 }
 
+void ShowTextEditControl(int x, int y, char *s)
+{
+    if(GraphicsEditControlIsVisible()) return;
+
+    // Note: TextEditControl->position() does NOT set (x,y) position!
+    // It changes the cursor postion in the input widget
+    // Use the :: operator to avoid confusion
+    TextEditControl->Fl_Widget::position(x, y);
+    if(s) TextEditControl->value(s);
+    TextEditControl->show();
+
+    // Grab focus and select all to ease editing
+    TextEditControl->take_focus();
+    TextEditControl->Fl_Input::position(TextEditControl->size());
+    TextEditControl->mark(0);
+
+}
+
+void HideTextEditControl(void)
+{
+    // return focus to the GL window before hiding the widget
+    // this avoid the disapparition of the mouse pointer if it was over the widget
+    TextGlWnd->take_focus();
+
+    TextEditControl->hide();
+}
+
+bool TextEditControlIsVisible(void)
+{
+    return TextEditControl->visible();
+}
+
+void ShowGraphicsEditControl(int x, int y, char *s)
+{
+    if(GraphicsEditControlIsVisible()) return;
+
+    // Convert to ij (vs. xy) style coordinates,
+    // and compensate for the input widget height due to inverse coord
+    x = x + GraphicsGlWnd->w()/2;
+    y = -y + GraphicsGlWnd->h()/2 - GraphicsEditControl->h();
+
+    // Use of the :: 0perator to avoid confusion with the Fl_input positon metod.
+    GraphicsEditControl->Fl_Widget::position(x, y);
+    GraphicsEditControl->value(s);
+    GraphicsEditControl->show();
+
+    // Grab focus and select all to ease editing
+    GraphicsEditControl->take_focus();
+    GraphicsEditControl->Fl_Input::position(GraphicsEditControl->size());
+    GraphicsEditControl->mark(0);
+
+}
+
+void HideGraphicsEditControl(void)
+{
+    // return focus to the GL window before hiding the widget
+    // this avoid the disapparition of the mouse pointer if it was over the widget
+    GraphicsGlWnd->take_focus();
+
+    GraphicsEditControl->hide();
+}
+
+bool GraphicsEditControlIsVisible(void)
+{
+    return GraphicsEditControl->visible();
+}
+
 void InvalidateText(void)
 {
     TextGlWnd->redraw();

src/fltk/xFl_Gl_Window_Group.H

@@ -82,6 +82,9 @@ public:
   */
   virtual int handle_gl(int event);
 
+  // override resize
+  virtual void resize(int x, int y,int w, int h);
+
 protected:
 
   void draw(void);

src/fltk/xFl_Gl_Window_Group.cxx

@@ -169,6 +169,12 @@ int Fl_Gl_Window_Group::handle_gl(int event) {
   return 0;
 }
 
+void Fl_Gl_Window_Group::resize(int x, int y,int w, int h)
+{
+    glstandin->resize(x,y,w,h);
+    Fl_Window::resize(x,y,w,h);
+}
+
 void Fl_Gl_Window_Group::flush(void) {
   // Fl_Window::make_current() does this, but not
   // Fl_Gl_Window::make_current(), and we can't override make_current()