fix multi monitors even more

When a monitor is created or removed, the geometries of the old ones
must be updated. This is also more efficient than before since we
calculate the monitor geometries only when creating and destroying
monitors. arrangelayers() is needed to recalculate m->w. arrange() is so
clients don't move to the left monitor when plugging or unplugging
monitors (clients keep the same coordinates but the field below them
changes).

1 files changed, 15 insertions, 6 deletions

diff --git a/dwl.c b/dwl.c
index 7bf8e5b..0d92d35 100644
--- a/dwl.c
+++ b/dwl.c
@@ -472,7 +472,7 @@ void
 arrangelayer(Monitor *m, struct wl_list *list, struct wlr_box *usable_area, bool exclusive)
 {
 	LayerSurface *layersurface;
-	struct wlr_box full_area = *wlr_output_layout_get_box(output_layout, m->wlr_output);
+	struct wlr_box full_area = m->m;
 
 	wl_list_for_each(layersurface, list, link) {
 		struct wlr_layer_surface_v1 *wlr_layer_surface = layersurface->layer_surface;
@@ -547,7 +547,7 @@ arrangelayer(Monitor *m, struct wl_list *list, struct wlr_box *usable_area, bool
 void
 arrangelayers(Monitor *m)
 {
-	struct wlr_box usable_area = *wlr_output_layout_get_box(output_layout, m->wlr_output);
+	struct wlr_box usable_area = m->m;
 	uint32_t layers_above_shell[] = {
 		ZWLR_LAYER_SHELL_V1_LAYER_OVERLAY,
 		ZWLR_LAYER_SHELL_V1_LAYER_TOP,
@@ -690,6 +690,12 @@ cleanupmon(struct wl_listener *listener, void *data)
 
 	wl_list_remove(&m->destroy.link);
 	free(m);
+
+	wl_list_for_each(m, &mons, link) {
+		m->m = m->w = *wlr_output_layout_get_box(output_layout, m->wlr_output);
+		arrangelayers(m);
+		arrange(m);
+	}
 }
 
 void
@@ -813,13 +819,16 @@ createmon(struct wl_listener *listener, void *data)
 	wlr_output_layout_add_auto(output_layout, wlr_output);
 	sgeom = *wlr_output_layout_get_box(output_layout, NULL);
 
-	/* Get effective monitor geometry to use for window area */
-	m->m = *wlr_output_layout_get_box(output_layout, m->wlr_output);
-	m->w = m->m;
-
 	for (size_t i = 0; i < nlayers; ++i) {
 		wl_list_init(&m->layers[i]);
 	}
+
+	/* Get effective monitor geometry to use for window area */
+	wl_list_for_each(m, &mons, link) {
+		m->m = m->w = *wlr_output_layout_get_box(output_layout, m->wlr_output);
+		arrangelayers(m);
+		arrange(m);
+	}
 }
 
 void