From f48bcb1a1781c898f7d3f4d667b9745b560f6712 Mon Sep 17 00:00:00 2001
From: Kovid Goyal <kovid@kovidgoyal.net>
Date: Thu, 26 Sep 2024 00:49:04 +0530
Subject: [PATCH] Wayland GNOME: Fix a crash when using multiple monitors with
 different scales and starting on or moving to the monitor with lower scale

Fucking GNOME and its fucking lack of support for SSD. How much of my
life I have wasted on these nincompoops.

Fixes #7894
---
 docs/changelog.rst                |  5 +++++
 glfw/wl_client_side_decorations.c | 11 +++++------
 2 files changed, 10 insertions(+), 6 deletions(-)

diff --git a/docs/changelog.rst b/docs/changelog.rst
index 8ffe6de36..aab0d9c33 100644
--- a/docs/changelog.rst
+++ b/docs/changelog.rst
@@ -74,6 +74,11 @@ consumption to do the same tasks.
 Detailed list of changes
 -------------------------------------
 
+0.36.4 [future]
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+- Wayland GNOME: Fix a crash when using multiple monitors with different scales and starting on or moving to the monitor with lower scale (:iss:`7894`)
+
 0.36.3 [2024-09-25]
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 
diff --git a/glfw/wl_client_side_decorations.c b/glfw/wl_client_side_decorations.c
index d2fb2710a..bef02b2b6 100644
--- a/glfw/wl_client_side_decorations.c
+++ b/glfw/wl_client_side_decorations.c
@@ -468,10 +468,8 @@ render_shadows(_GLFWwindow *window) {
 
 static bool
 create_shm_buffers(_GLFWwindow* window) {
-    const double scale = _glfwWaylandWindowScale(window);
-
     decs.mapping.size = 0;
-#define bp(which, width, height) decs.mapping.size += init_buffer_pair(&decs.which.buffer, width, height, scale);
+#define bp(which, width, height) decs.mapping.size += init_buffer_pair(&decs.which.buffer, width, height, decs.for_window_state.fscale);
     bp(titlebar, window->wl.width, decs.metrics.visible_titlebar_height);
     bp(shadow_top, window->wl.width, decs.metrics.width);
     bp(shadow_bottom, window->wl.width, decs.metrics.width);
@@ -504,7 +502,7 @@ create_shm_buffers(_GLFWwindow* window) {
     wl_shm_pool_destroy(pool);
     render_title_bar(window, true);
     render_shadows(window);
-    debug("Created decoration buffers at scale: %f\n", scale);
+    debug("Created decoration buffers at scale: %f\n", decs.for_window_state.fscale);
     return true;
 }
 
@@ -577,10 +575,11 @@ ensure_csd_resources(_GLFWwindow *window) {
     if (!window_is_csd_capable(window)) return false;
     const bool is_focused = window->id == _glfw.focusedWindowId;
     const bool focus_changed = is_focused != decs.for_window_state.focused;
+    const double current_scale = _glfwWaylandWindowScale(window);
     const bool size_changed = (
         decs.for_window_state.width != window->wl.width ||
         decs.for_window_state.height != window->wl.height ||
-        decs.for_window_state.fscale != _glfwWaylandWindowScale(window) ||
+        decs.for_window_state.fscale != current_scale ||
         !decs.mapping.data
     );
     const bool state_changed = decs.for_window_state.toplevel_states != window->wl.current.toplevel_states;
@@ -589,6 +588,7 @@ ensure_csd_resources(_GLFWwindow *window) {
             decs.for_window_state.width, decs.for_window_state.height, window->wl.width, window->wl.height, needs_update,
             size_changed, state_changed, decs.buffer_destroyed);
     if (!needs_update) return false;
+    decs.for_window_state.fscale = current_scale;  // used in create_shm_buffers
     if (size_changed || decs.buffer_destroyed) {
         free_csd_buffers(window);
         if (!create_shm_buffers(window)) return false;
@@ -618,7 +618,6 @@ ensure_csd_resources(_GLFWwindow *window) {
 
     decs.for_window_state.width = window->wl.width;
     decs.for_window_state.height = window->wl.height;
-    decs.for_window_state.fscale = _glfwWaylandWindowScale(window);
     decs.for_window_state.focused = is_focused;
     decs.for_window_state.toplevel_states = window->wl.current.toplevel_states;
     return true;