Refactor seat operations to use an interface

This splits each seat operation (drag/move tiling/floating etc) into a
separate file and introduces a struct sway_seatop_impl to abstract the
operation.

The move_tiling_threshold operation has been merged into move_tiling.

The main logic for each operation is untouched aside from variable
renames.

The following previously-static functions have been made public:
* node_at_coords
* container_raise_floating
* render_rect
* premultiply_alpha
* scale_box

1 files changed, 2 insertions, 0 deletions

diff --git a/include/sway/tree/container.h b/include/sway/tree/container.h
index 1d0a0ad1..9a432cb2 100644
--- a/include/sway/tree/container.h
+++ b/include/sway/tree/container.h
@@ -333,4 +333,6 @@ void container_add_mark(struct sway_container *container, char *mark);
 
 void container_update_marks_textures(struct sway_container *container);
 
+void container_raise_floating(struct sway_container *con);
+
 #endif