mirrors
/
fltk
mirror of https://github.com/fltk/fltk
1
0
Fork 0
Code Issues Packages Projects Releases Wiki Activity

Wayland: document throttling redraws during interactive resizes

This commit is contained in:
ManoloFLTK 2023-10-03 08:12:13 +02:00
parent 76b16d8cef
commit 74e63d9077
1 changed files with 15 additions and 2 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

17
documentation/src/wayland.dox
View File

@ -618,14 +618,27 @@ has the effect that when the mapping operation eventually completes, Wayland run
\c draw_buffer_needs_commit member is true. The net result is that the screen
shows the most recent surface content.
This synchronization mechanism is also used when performing an interactive window resize
operation. During such operation, the compositor informs the client an interactive
resize is being performed and sends window resize commands at high rate (~60 Hz) to the
client via the socket. Libdecor turns on flag \c LIBDECOR_WINDOW_STATE_RESIZING
to inform the client, and runs function \c handle_configure() for each received resize
command. Before calling Fl_Group::resize() and later Fl_Window::draw(),
\c handle_configure() tests whether \c window->buffer->cb is NULL. When it's not
because a previous resize operation is being performed, the current resize command is
skipped. At the end of the interactive resize, flag \c LIBDECOR_WINDOW_STATE_RESIZING
is off and Wayland sends a final resize command which is not skipped. Overall, this
ensures the client program resizes its window as frequently as it can without
falling behind resize commands sent by the compositor.
<h3>Progressive window drawing</h3>
FLTK supports progressive drawing when an app calls function Fl_Window::make_current()
at any time and then calls the FLTK drawing API. This is made possible
in function \c Fl_Wayland_Window_Driver::make_current() with
\code
// to support progressive drawing
if ( (!Fl_Wayland_Window_Driver::in_flush_) && window->buffer && (!window->buffer->cb) &&
!wait_for_expose_value ) {
if ( (!Fl_Wayland_Window_Driver::in_flush_) && window->buffer && (!window->buffer->cb)
&& window->buffer->draw_buffer_needs_commit && (!wait_for_expose_value) ) {
Fl_Wayland_Graphics_Driver::buffer_commit(window);
}
\endcode