diff options
Diffstat (limited to 'documentation')
| -rw-r--r-- | documentation/src/wayland.dox | 18 |
1 files changed, 14 insertions, 4 deletions
diff --git a/documentation/src/wayland.dox b/documentation/src/wayland.dox index f0decf1b0..7a3e11296 100644 --- a/documentation/src/wayland.dox +++ b/documentation/src/wayland.dox @@ -44,8 +44,16 @@ app as parameters of these calls. Each listener is first associated to its corre Wayland object by a call to a specific Wayland function of the form \c wl_XXX_add_listener(). Wayland differs noticeably from X11 in that the position of a window in the display is -completely hidden to the client app. Besides toplevel and sub-windows, Wayland -allows to create popup windows positioned relatively to a previously mapped other window. +completely hidden to the client app. This prevents function \c Fl_Window::position() from having +any effect on a top-level window. Wayland also prevents a client app from knowing whether +a window is minimized: \c Fl_Window::show() has no effect on an already mapped window. +Subwindows can be positionned as usual relatively to their +parent window. FLTK uses that for the small, yellow windows that display +the new scale factor value when it's changed: these are created as short-lived subwindows +centered above \c Fl::first_window(). +Wayland allows to create popup windows positioned relatively to a previously mapped other +window, with the sole restriction that any popup must intersect or at least touch that other +window. This allows FLTK to create menus and tooltips, but it seriously complicates the algorithm to pilot menus, because the previous algorithm conceived for other platforms assumes the position of a window in the display to be known to the client app, which is wrong @@ -280,7 +288,8 @@ above unfold. \section wayland-graphics-driver Fl_Wayland_Graphics_Driver and Fl_Cairo_Graphics_Driver -Wayland uses an \c Fl_Wayland_Graphics_Driver object for all its on-screen drawing operations. +The Wayland platform of FLTK uses an \c Fl_Wayland_Graphics_Driver object for all its on-screen +drawing operations. This object is created by function \c Fl_Graphics_Driver::newMainGraphicsDriver() called by \c Fl_Display_Device::display_device() when the library opens the display. New \c Fl_Wayland_Graphics_Driver objects are also created for each \c Fl_Image_Surface and @@ -389,7 +398,8 @@ That's done by member function \c Fl_Wayland_Graphics_Driver::create_shm_buffer( which follows this 3-step procedure to create a "buffer factory" for FLTK and construct Wayland buffers from it: - Libdecor function <tt>os_create_anonymous_file(off_t size)</tt> creates an adequate file and mmap's -it. FLTK initially sets this file size to \c pool_size = 10 MB. This size will be increased when and +it. This file lives in RAM because it is created by function \c memfd_create(). +FLTK initially sets this file size to \c pool_size = 10 MB. This size will be increased when and if necessary. FLTK stores in variable \c pool_memory the address of the beginning of the mmap'ed memory structure. - Wayland function \c wl_shm_create_pool() has this mmap'ed memory shared with the |