From 0a98d848dee7a0dc0dc6a7f6743f4cebbba9a29a Mon Sep 17 00:00:00 2001
From: Kovid Goyal <kovid@kovidgoyal.net>
Date: Sat, 29 Jun 2024 11:07:02 +0530
Subject: [PATCH] Wayland redraw OS window twice after resize

Needed on, for instance sway to get it to recognize that the framebuffer
has been resized.
---
 kitty/child-monitor.c | 9 ++++++---
 kitty/glfw.c          | 4 ++--
 kitty/state.c         | 4 ++--
 kitty/state.h         | 4 ++--
 4 files changed, 12 insertions(+), 9 deletions(-)

diff --git a/kitty/child-monitor.c b/kitty/child-monitor.c
index 6d2c343e7..e299a01f7 100644
--- a/kitty/child-monitor.c
+++ b/kitty/child-monitor.c
@@ -810,7 +810,7 @@ render_prepared_os_window(OSWindow *os_window, unsigned int active_window_id, co
     swap_window_buffers(os_window);
     os_window->last_active_tab = os_window->active_tab; os_window->last_num_tabs = os_window->num_tabs; os_window->last_active_window_id = active_window_id;
     os_window->focused_at_last_render = os_window->is_focused;
-    os_window->is_damaged = false;
+    if (os_window->redraw_count) os_window->redraw_count--;
     if (USE_RENDER_FRAMES) request_frame_render(os_window);
 #undef WD
 #undef TD
@@ -848,7 +848,7 @@ render_os_window(OSWindow *w, monotonic_t now, bool ignore_render_frames, bool s
     w->render_calls++;
     make_os_window_context_current(w);
     if (w->live_resize.in_progress) blank_os_window(w);
-    bool needs_render = w->is_damaged || w->live_resize.in_progress;
+    bool needs_render = w->redraw_count > 0 || w->live_resize.in_progress;
     if (w->viewport_size_dirty) {
         w->clear_count = 0;
         update_surface_size(w->viewport_width, w->viewport_height, 0);
@@ -1073,7 +1073,10 @@ process_pending_resizes(monotonic_t now) {
                 update_os_window_viewport(w, true);
                 change_live_resize_state(w, false);
                 zero_at_ptr(&w->live_resize);
-                w->is_damaged = true;  // because the window size should be hidden even if update_os_window_viewport does nothing
+                // because the window size should be hidden even if update_os_window_viewport does nothing
+                // On Wayland some compositors require two redraws after a
+                // resize to actually render correctly (Run kitty -1 --wait-for-os-window-close in sway to reproduce)
+                w->redraw_count = global_state.is_wayland ? 2 : 1;
             }
         }
     }
diff --git a/kitty/glfw.c b/kitty/glfw.c
index 23ed84da0..ff97d049e 100644
--- a/kitty/glfw.c
+++ b/kitty/glfw.c
@@ -362,7 +362,7 @@ dpi_change_callback(GLFWwindow *w, float x_scale UNUSED, float y_scale UNUSED) {
 static void
 refresh_callback(GLFWwindow *w) {
     if (!set_callback_window(w)) return;
-    global_state.callback_os_window->is_damaged = true;
+    if (!global_state.callback_os_window->redraw_count) global_state.callback_os_window->redraw_count++;
     global_state.callback_os_window = NULL;
     request_tick_callback();
 }
@@ -1330,7 +1330,7 @@ create_os_window(PyObject UNUSED *self, PyObject *args, PyObject *kw) {
     // macOS: Show the window after it is ready
     glfwShowWindow(glfw_window);
 #endif
-    w->is_damaged = true;
+    w->redraw_count = 1;
     debug("OS Window created\n");
     return PyLong_FromUnsignedLongLong(w->id);
 }
diff --git a/kitty/state.c b/kitty/state.c
index 2890bb3c9..d321aa004 100644
--- a/kitty/state.c
+++ b/kitty/state.c
@@ -913,7 +913,7 @@ PYWRAP1(change_background_opacity) {
     PA("Kf", &os_window_id, &opacity);
     WITH_OS_WINDOW(os_window_id)
         os_window->background_opacity = opacity;
-        os_window->is_damaged = true;
+        if (!os_window->redraw_count) os_window->redraw_count++;
         Py_RETURN_TRUE;
     END_WITH_OS_WINDOW
     Py_RETURN_FALSE;
@@ -1123,7 +1123,7 @@ PYWRAP0(apply_options_update) {
         OSWindow *os_window = global_state.os_windows + o;
         get_platform_dependent_config_values(os_window->handle);
         os_window->background_opacity = OPT(background_opacity);
-        os_window->is_damaged = true;
+        if (!os_window->redraw_count) os_window->redraw_count++;
         for (size_t t = 0; t < os_window->num_tabs; t++) {
             Tab *tab = os_window->tabs + t;
             for (size_t w = 0; w < tab->num_windows; w++) {
diff --git a/kitty/state.h b/kitty/state.h
index d8db29da3..b9b27f01d 100644
--- a/kitty/state.h
+++ b/kitty/state.h
@@ -254,8 +254,8 @@ typedef struct {
     bool viewport_size_dirty, viewport_updated_at_least_once;
     monotonic_t viewport_resized_at;
     LiveResizeInfo live_resize;
-    bool has_pending_resizes, is_semi_transparent, shown_once, is_damaged, ignore_resize_events;
-    unsigned int clear_count;
+    bool has_pending_resizes, is_semi_transparent, shown_once, ignore_resize_events;
+    unsigned int clear_count, redraw_count;
     WindowChromeState last_window_chrome;
     float background_opacity;
     FONTS_DATA_HANDLE fonts_data;