New feature: adjust gaps with floating_mod+scroll

I made this configurable but I didn't make the command for it. That's
left as an exercise to an eager contributor.

    mod_scroll_behavior [gaps inner|gaps outer]

Would merge implementions of more behaviors for mod+scroll, if anyone
has some neato ideas.

3 files changed, 34 insertions, 0 deletions

diff --git a/include/config.h b/include/config.h
index fb84423c..0ef8c5bf 100644
--- a/include/config.h
+++ b/include/config.h
@@ -163,6 +163,13 @@ enum edge_border_types {
         E_BOTH          /**< hide vertical and horizontal edge borders */
 };
 
+enum floating_scroll_behavior {
+    FSB_GAPS_OUTER,     /**< Adjust outer gaps */
+    FSB_GAPS_INNER      /**< Adjust inner gaps */
+    // Note: in the future I expect to see more things you can do with the scroll
+    // wheel than maniuplating gaps
+};
+
 /**
  * The configuration struct. The result of loading a config file.
  */
@@ -181,6 +188,7 @@ struct sway_config {
         uint32_t floating_mod;
         uint32_t dragging_key;
         uint32_t resizing_key;
+    enum floating_scroll_behavior floating_scroll; // TODO: command to set this
         enum swayc_layouts default_orientation;
         enum swayc_layouts default_layout;
         char *font;
diff --git a/sway/config.c b/sway/config.c
index 5501ab31..f6241a3d 100644
--- a/sway/config.c
+++ b/sway/config.c
@@ -159,6 +159,7 @@ static void config_defaults(struct sway_config *config) {
         config->floating_mod = 0;
         config->dragging_key = M_LEFT_CLICK;
         config->resizing_key = M_RIGHT_CLICK;
+        config->floating_scroll = FSB_GAPS_INNER;
         config->default_layout = L_NONE;
         config->default_orientation = L_NONE;
         config->font = strdup("monospace 10");
diff --git a/sway/handlers.c b/sway/handlers.c
index 54326dd0..9648e729 100644
--- a/sway/handlers.c
+++ b/sway/handlers.c
@@ -647,6 +647,31 @@ static bool handle_pointer_button(wlc_handle view, uint32_t time, const struct w
         case M_SCROLL_DOWN:
                 break;
         }
+        if (!(modifiers->mods ^ config->floating_mod) &&
+                        (button == M_SCROLL_UP || button == M_SCROLL_DOWN)) {
+                switch (config->floating_scroll) {
+                case FSB_GAPS_INNER:
+                case FSB_GAPS_OUTER:
+                        {
+                                int amount = button == M_SCROLL_UP ? -1 : 1;
+                                int i,j;
+                                for (i = 0; i < root_container.children->length; ++i) {
+                                        swayc_t *op = root_container.children->items[i];
+                                        for (j = 0; j < op->children->length; ++j) {
+                                                swayc_t *ws = op->children->items[j];
+                                                // TODO: adjust outer gaps ws->gaps = 0;
+                                                if (config->floating_scroll == FSB_GAPS_INNER) {
+                                                        container_map(ws, add_gaps, &amount);
+                                                } else {
+                                                        ws->gaps += amount;
+                                                }
+                                        }
+                                }
+                                arrange_windows(&root_container, -1, -1);
+                                break;
+                        }
+                }
+        }
 
         // get focused window and check if to change focus on mouse click
         swayc_t *focused = get_focused_container(&root_container);