Bugfix: Fix coordinates when the rect of an output changes (Thanks Paul)

Fixes #623

include/floating.h

@@ -146,4 +146,11 @@ void drag_pointer(Con *con, const xcb_button_press_event_t *event,
  */
 void floating_reposition(Con *con, Rect newrect);
 
+/**
+ * Fixes the coordinates of the floating window whenever the window gets
+ * reassigned to a different output (or when the output’s rect changes).
+ *
+ */
+void floating_fix_coordinates(Con *con, Rect *old_rect, Rect *new_rect);
+
 #endif

src/con.c

@@ -613,20 +613,7 @@ void con_move_to_workspace(Con *con, Con *workspace, bool fix_coordinates, bool
         /* Take the relative coordinates of the current output, then add them
          * to the coordinate space of the correct output */
         if (fix_coordinates && con->type == CT_FLOATING_CON) {
-            DLOG("Floating window, fixing coordinates\n");
-            /* First we get the x/y coordinates relative to the x/y coordinates
-             * of the output on which the window is on */
-            uint32_t rel_x = (con->rect.x - source_output->rect.x);
-            uint32_t rel_y = (con->rect.y - source_output->rect.y);
-            /* Then we calculate a fraction, for example 0.63 for a window
-             * which is at y = 1212 of a 1920 px high output */
-            double fraction_x = ((double)rel_x / source_output->rect.width);
-            double fraction_y = ((double)rel_y / source_output->rect.height);
-            DLOG("rel_x = %d, rel_y = %d, fraction_x = %f, fraction_y = %f, output->w = %d, output->h = %d\n",
-                 rel_x, rel_y, fraction_x, fraction_y, source_output->rect.width, source_output->rect.height);
-            con->rect.x = dest_output->rect.x + (fraction_x * dest_output->rect.width);
-            con->rect.y = dest_output->rect.y + (fraction_y * dest_output->rect.height);
-            DLOG("Resulting coordinates: x = %d, y = %d\n", con->rect.x, con->rect.y);
+            floating_fix_coordinates(con, &(source_output->rect), &(dest_output->rect));
         } else DLOG("Not fixing coordinates, fix_coordinates flag = %d\n", fix_coordinates);
 
         /* If moving to a visible workspace, call show so it can be considered

src/floating.c

@@ -551,6 +551,28 @@ void floating_reposition(Con *con, Rect newrect) {
     tree_render();
 }
 
+/*
+ * Fixes the coordinates of the floating window whenever the window gets
+ * reassigned to a different output (or when the output’s rect changes).
+ *
+ */
+void floating_fix_coordinates(Con *con, Rect *old_rect, Rect *new_rect) {
+    DLOG("Fixing coordinates of floating window %p\n", con);
+    /* First we get the x/y coordinates relative to the x/y coordinates
+     * of the output on which the window is on */
+    uint32_t rel_x = (con->rect.x - old_rect->x);
+    uint32_t rel_y = (con->rect.y - old_rect->y);
+    /* Then we calculate a fraction, for example 0.63 for a window
+     * which is at y = 1212 of a 1920 px high output */
+    double fraction_x = ((double)rel_x / old_rect->width);
+    double fraction_y = ((double)rel_y / old_rect->height);
+    DLOG("rel_x = %d, rel_y = %d, fraction_x = %f, fraction_y = %f, output->w = %d, output->h = %d\n",
+         rel_x, rel_y, fraction_x, fraction_y, old_rect->width, old_rect->height);
+    con->rect.x = new_rect->x + (fraction_x * new_rect->width);
+    con->rect.y = new_rect->y + (fraction_y * new_rect->height);
+    DLOG("Resulting coordinates: x = %d, y = %d\n", con->rect.x, con->rect.y);
+}
+
 #if 0
 /*
  * Moves the client 10px to the specified direction.

src/randr.c

@@ -2,7 +2,7 @@
  * vim:ts=4:sw=4:expandtab
  *
  * i3 - an improved dynamic tiling window manager
- * © 2009-2011 Michael Stapelberg and contributors (see also: LICENSE)
+ * © 2009-2012 Michael Stapelberg and contributors (see also: LICENSE)
  *
  * For more information on RandR, please see the X.org RandR specification at
  * http://cgit.freedesktop.org/xorg/proto/randrproto/tree/randrproto.txt
@@ -511,8 +511,6 @@ void init_ws_for_output(Output *output, Con *content) {
  *
  */
 static void output_change_mode(xcb_connection_t *conn, Output *output) {
-    //i3Font *font = load_font(conn, config.font);
-
     DLOG("Output mode changed, updating rect\n");
     assert(output->con != NULL);
     output->con->rect = output->rect;
@@ -522,6 +520,14 @@ static void output_change_mode(xcb_connection_t *conn, Output *output) {
     /* Point content to the container of the workspaces */
     content = output_get_content(output->con);
 
+    /* Fix the position of all floating windows on this output.
+     * The 'rect' of each workspace will be updated in src/render.c. */
+    TAILQ_FOREACH(workspace, &(content->nodes_head), nodes) {
+        TAILQ_FOREACH(child, &(workspace->floating_head), floating_windows) {
+            floating_fix_coordinates(child, &(workspace->rect), &(output->con->rect));
+        }
+    }
+
     /* If default_orientation is NO_ORIENTATION, we change the orientation of
      * the workspaces and their childs depending on output resolution. This is
      * only done for workspaces with maximum one child. */