Implement popup_during_fullscreen

This introduces a new view_impl function: is_transient_for. Similar to
container_has_ancestor but works using the surface parents rather than
the tree.

This patch modifies view_is_visible, container_at and so on to allow
transient views to function normally when they're in front of a
fullscreen view.

2 files changed, 24 insertions, 1 deletions

diff --git a/sway/input/cursor.c b/sway/input/cursor.c
index 331c6c7e..08eeb812 100644
--- a/sway/input/cursor.c
+++ b/sway/input/cursor.c
@@ -98,6 +98,22 @@ static struct sway_node *node_at_coords(
 		return NULL;
 	}
 	if (ws->fullscreen) {
+		// Try transient containers
+		if (config->popup_during_fullscreen == POPUP_SMART &&
+				ws->fullscreen->view) {
+			for (int i = 0; i < ws->floating->length; ++i) {
+				struct sway_container *floater = ws->floating->items[i];
+				if (floater->view && view_is_transient_for(
+							floater->view, ws->fullscreen->view)) {
+					struct sway_container *con = tiling_container_at(
+							&floater->node, lx, ly, surface, sx, sy);
+					if (con) {
+						return &con->node;
+					}
+				}
+			}
+		}
+		// Try fullscreen container
 		struct sway_container *con =
 			tiling_container_at(&ws->fullscreen->node, lx, ly, surface, sx, sy);
 		if (con) {
diff --git a/sway/input/seat.c b/sway/input/seat.c
index f5cb2f9e..690b59e6 100644
--- a/sway/input/seat.c
+++ b/sway/input/seat.c
@@ -655,7 +655,14 @@ void seat_set_focus_warp(struct sway_seat *seat, struct sway_node *node,
 	// Deny setting focus to a view which is hidden by a fullscreen container
 	if (new_workspace && new_workspace->fullscreen && container &&
 			!container_is_fullscreen_or_child(container)) {
-		return;
+		// Unless it's a transient container
+		bool is_transient = new_workspace->fullscreen->view &&
+			config->popup_during_fullscreen == POPUP_SMART &&
+			container->view && view_is_transient_for(
+					container->view, new_workspace->fullscreen->view);
+		if (!is_transient) {
+			return;
+		}
 	}
 
 	struct sway_output *last_output = last_workspace ?