diff options
| -rw-r--r-- | clients/window.c | 32 |
1 files changed, 32 insertions, 0 deletions
diff --git a/clients/window.c b/clients/window.c index b12c21c..ab9a36e 100644 --- a/clients/window.c +++ b/clients/window.c @@ -3363,6 +3363,36 @@ surface_resize(struct surface *surface) } static void +hack_prevent_EGL_sub_surface_deadlock(struct window *window) +{ + /* + * This hack should be removed, when EGL respects + * eglSwapInterval(0). + * + * If this window has sub-surfaces, especially a free-running + * EGL-widget, we need to post the parent surface once with + * all the old state to guarantee, that the EGL-widget will + * receive its frame callback soon. Otherwise, a forced call + * to eglSwapBuffers may end up blocking, waiting for a frame + * event that will never come, because we will commit the parent + * surface with all new state only after eglSwapBuffers returns. + * + * This assumes, that: + * 1. When the EGL widget's resize hook is called, it pauses. + * 2. When the EGL widget's redraw hook is called, it forces a + * repaint and a call to eglSwapBuffers(), and maybe resumes. + * In a single threaded application condition 1 is a no-op. + * + * XXX: This should actually be after the surface_resize() calls, + * but cannot, because then it would commit the incomplete state + * accumulated from the widget resize hooks. + */ + if (window->subsurface_list.next != &window->main_surface->link || + window->subsurface_list.prev != &window->main_surface->link) + wl_surface_commit(window->main_surface->surface); +} + +static void idle_resize(struct window *window) { struct surface *surface; @@ -3370,6 +3400,8 @@ idle_resize(struct window *window) window->resize_needed = 0; window->redraw_needed = 1; + hack_prevent_EGL_sub_surface_deadlock(window); + widget_set_allocation(window->main_surface->widget, window->pending_allocation.x, window->pending_allocation.y, |