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, 92 insertions, 0 deletions

diff --git a/sway/input/seatop_resize_tiling.c b/sway/input/seatop_resize_tiling.c
new file mode 100644
index 00000000..30431f04
--- /dev/null
+++ b/sway/input/seatop_resize_tiling.c
@@ -0,0 +1,92 @@
+#define _POSIX_C_SOURCE 200809L
+#include <wlr/types/wlr_cursor.h>
+#include "sway/commands.h"
+#include "sway/input/cursor.h"
+#include "sway/input/seat.h"
+
+struct seatop_resize_tiling_event {
+        struct sway_container *con;
+        enum wlr_edges edge;
+        double ref_lx, ref_ly;         // cursor's x/y at start of op
+        double ref_width, ref_height;  // container's size at start of op
+        double ref_con_lx, ref_con_ly; // container's x/y at start of op
+};
+
+static void handle_motion(struct sway_seat *seat, uint32_t time_msec) {
+        struct seatop_resize_tiling_event *e = seat->seatop_data;
+        int amount_x = 0;
+        int amount_y = 0;
+        int moved_x = seat->cursor->cursor->x - e->ref_lx;
+        int moved_y = seat->cursor->cursor->y - e->ref_ly;
+        enum wlr_edges edge_x = WLR_EDGE_NONE;
+        enum wlr_edges edge_y = WLR_EDGE_NONE;
+        struct sway_container *con = e->con;
+
+        if (e->edge & WLR_EDGE_TOP) {
+                amount_y = (e->ref_height - moved_y) - con->height;
+                edge_y = WLR_EDGE_TOP;
+        } else if (e->edge & WLR_EDGE_BOTTOM) {
+                amount_y = (e->ref_height + moved_y) - con->height;
+                edge_y = WLR_EDGE_BOTTOM;
+        }
+        if (e->edge & WLR_EDGE_LEFT) {
+                amount_x = (e->ref_width - moved_x) - con->width;
+                edge_x = WLR_EDGE_LEFT;
+        } else if (e->edge & WLR_EDGE_RIGHT) {
+                amount_x = (e->ref_width + moved_x) - con->width;
+                edge_x = WLR_EDGE_RIGHT;
+        }
+
+        if (amount_x != 0) {
+                container_resize_tiled(e->con, edge_x, amount_x);
+        }
+        if (amount_y != 0) {
+                container_resize_tiled(e->con, edge_y, amount_y);
+        }
+}
+
+static void handle_finish(struct sway_seat *seat) {
+        cursor_set_image(seat->cursor, "left_ptr", NULL);
+}
+
+static void handle_abort(struct sway_seat *seat) {
+        cursor_set_image(seat->cursor, "left_ptr", NULL);
+}
+
+static void handle_unref(struct sway_seat *seat, struct sway_container *con) {
+        struct seatop_resize_tiling_event *e = seat->seatop_data;
+        if (e->con == con) {
+                seatop_abort(seat);
+        }
+}
+
+static const struct sway_seatop_impl seatop_impl = {
+        .motion = handle_motion,
+        .finish = handle_finish,
+        .abort = handle_abort,
+        .unref = handle_unref,
+};
+
+void seatop_begin_resize_tiling(struct sway_seat *seat,
+                struct sway_container *con, uint32_t button, enum wlr_edges edge) {
+        seatop_abort(seat);
+
+        struct seatop_resize_tiling_event *e =
+                calloc(1, sizeof(struct seatop_resize_tiling_event));
+        if (!e) {
+                return;
+        }
+        e->con = con;
+        e->edge = edge;
+
+        e->ref_lx = seat->cursor->cursor->x;
+        e->ref_ly = seat->cursor->cursor->y;
+        e->ref_con_lx = con->x;
+        e->ref_con_ly = con->y;
+        e->ref_width = con->width;
+        e->ref_height = con->height;
+
+        seat->seatop_impl = &seatop_impl;
+        seat->seatop_data = e;
+        seat->seatop_button = button;
+}