diff options
Diffstat (limited to 'src')
| -rw-r--r-- | src/Fl_Window.cxx | 18 |
1 files changed, 18 insertions, 0 deletions
diff --git a/src/Fl_Window.cxx b/src/Fl_Window.cxx index a999511d2..f489fe89a 100644 --- a/src/Fl_Window.cxx +++ b/src/Fl_Window.cxx @@ -642,6 +642,24 @@ int Fl_Window::screen_num() { return pWindowDriver->screen_num(); } +/** Set the number of the screen where to map the window. + Call this and set also the window's desired position before show()'ing the window. + This can be necessary when a system has several screens with + distinct scaling factor values because the window's x() and y() may not suffice to + uniquely identify one screen. + To see that, consider a system with two screens where the screen at left is A pixel-wide + and has a scale factor of 1 whereas the screen at right has a scale factor of 2. + For the sake of simplicity, consider only + the X coordinates of windows. FLTK coordinates translate directly to pixel coordinates on the + left screen, whereas FLTK coordinates multiplied by 2 correspond to pixel coordinates + on the right screen. Consequently, FLTK coordinates between A/2 + 1 and A-1 can map to both + screens. Both window coordinates and screen number are necessary to uniquely identify + where a window is to be mapped. + */ +void Fl_Window::screen_num(int screen_num) { + if (!shown() && screen_num >= 0 && screen_num < Fl::screen_count()) pWindowDriver->screen_num(screen_num); +} + /** Assigns a non-rectangular shape to the window. This function gives an arbitrary shape (not just a rectangular region) to an Fl_Window. An Fl_Image of any dimension can be used as mask; it is rescaled to the window's dimension as needed. |