Only warp pointer once during x_push_changes()

- Introduce warp_to static variable in x.c that stores the coordinates
  to warp to as a Rect.

- Add x_set_warp_to function to set this variable.  Use in _tree_next,
  workspace_show, and con_move_to_workspace.

- In x_push_chanages, if warp_to is set, then call xcb_warp_pointer_rect
  and then reset it to NULL.

This fixes all know bugs for pointer warping for me.

include/x.h

@@ -104,4 +104,11 @@ void x_set_name(Con *con, const char *name);
  */
 void x_set_i3_atoms();
 
+/**
+ * Set warp_to coordinates.  This will trigger on the next call to
+ * x_push_changes().
+ *
+ */
+void x_set_warp_to(Rect *rect);
+
 #endif

src/con.c

@@ -591,6 +591,13 @@ void con_move_to_workspace(Con *con, Con *workspace) {
     if (source_output != dest_output &&
         workspace_is_visible(workspace)) {
         workspace_show(workspace->name);
+
+        /* Unset warp_to if target con is floating.  Otherwise, set warp_to to
+         * current target container. */
+        if (con->type == CT_FLOATING_CON)
+            x_set_warp_to(NULL);
+        else
+            x_set_warp_to(&(con->rect));
     }
 
     DLOG("Re-attaching container to %p / %s\n", next, next->name);

src/tree.c

@@ -414,8 +414,10 @@ static bool _tree_next(Con *con, char way, orientation_t orientation, bool wrap)
 
         workspace_show(workspace->name);
         Con *focus = con_descend_direction(workspace, direction);
-        if (focus)
+        if (focus) {
             con_focus(focus);
+            x_set_warp_to(&(focus->rect));
+        }
         return true;
     }
 

src/workspace.c

@@ -227,7 +227,7 @@ void workspace_show(const char *num) {
     /* Set mouse pointer */
     Con *new_output = con_get_output(focused);
     if (old_output != new_output) {
-       xcb_warp_pointer_rect(conn, &next->rect);
+        x_set_warp_to(&next->rect);
     }
 
     /* Update the EWMH hints */

src/x.c

@@ -12,6 +12,9 @@ xcb_window_t focused_id = XCB_NONE;
 static xcb_window_t *btt_stack;
 static int btt_stack_num;
 
+/* Stores coordinates to warp mouse pointer to if set */
+static Rect *warp_to;
+
 /*
  * Describes the X11 state we may modify (map state, position, window stack).
  * There is one entry per container. The state represents the current situation
@@ -862,6 +865,11 @@ void x_push_changes(Con *con) {
         focused_id = root;
     }
 
+    if (warp_to) {
+        xcb_warp_pointer_rect(conn, warp_to);
+        warp_to = NULL;
+    }
+
     xcb_flush(conn);
     DLOG("\n\n ENDING CHANGES\n\n");
 
@@ -937,3 +945,13 @@ void x_set_i3_atoms() {
     xcb_change_property(conn, XCB_PROP_MODE_REPLACE, root, A_I3_CONFIG_PATH, A_UTF8_STRING, 8,
                         strlen(current_configpath), current_configpath);
 }
+
+/*
+ * Set warp_to coordinates.  This will trigger on the next call to
+ * x_push_changes().
+ *
+ */
+void x_set_warp_to(Rect *rect)
+{
+    warp_to = rect;
+}

src/xcb.c

@@ -367,7 +367,9 @@ bool xcb_reply_contains_atom(xcb_get_property_reply_t *prop, xcb_atom_t atom) {
  *
  */
 void xcb_warp_pointer_rect(xcb_connection_t *conn, Rect *rect) {
-    xcb_warp_pointer(conn, XCB_NONE, root, 0, 0, 0, 0,
-        rect->x + (rect->width / 2),
-        rect->y + (rect->height / 2));
+    int mid_x = rect->x + (rect->width / 2);
+    int mid_y = rect->y + (rect->height / 2);
+
+    LOG("warp pointer to: %d %d\n", mid_x, mid_y);
+    xcb_warp_pointer(conn, XCB_NONE, root, 0, 0, 0, 0, mid_x, mid_y);
 }