Make corpses and skeletons stationary items (minmay)

Moving corpses and skeletons to other levels or to other locations
within a level is tedious but may be optimal for corpse rot and god
abilities like Kiku's corpse prayer. This commit prevents the player
from picking up or apporting carrion. It generalizes the code used for
nets being stationary, and cleans up and documents various bits of
related item pickup code.

1 files changed, 66 insertions, 26 deletions

diff --git a/crawl-ref/source/items.cc b/crawl-ref/source/items.cc
index 28cff29545..b5fb810b56 100644
--- a/crawl-ref/source/items.cc
+++ b/crawl-ref/source/items.cc
@@ -615,21 +615,39 @@ void lose_item_stack(const coord_def& where)
     igrd(where) = NON_ITEM;
 }
 
-static int _count_items(int obj)
+/*
+ * How many movable items are there at a location?
+ *
+ * @param obj The item link for the location.
+ * @returns The number of movable items at the location.
+*/
+int count_movable_items(int obj)
 {
     int result = 0;
 
     for (stack_iterator si(obj); si; ++si)
-        ++result;
-
+    {
+        if (!item_is_stationary(*si))
+            ++result;
+    }
     return result;
 }
 
-// Fill items with the items on a square.
-void item_list_on_square(vector<const item_def*>& items, int obj)
+/*
+ * Fill the given vector with the items on the given location link.
+ *
+ * @param[out] items A vector to hold the item_defs of the item.
+ * @param[in] obj The location link; an index in mitm.
+ * @param exclude_stationary If true, don't include stationary items.
+*/
+void item_list_on_square(vector<const item_def*>& items, int obj, bool exclude_stationary)
 {
     for (stack_iterator si(obj); si; ++si)
+    {
+        if (exclude_stationary && item_is_stationary(*si))
+            continue;
         items.push_back(& (*si));
+    }
 }
 
 bool need_to_autopickup()
@@ -819,7 +837,8 @@ void pickup_menu(int item_link)
     int n_tried_pickup = 0;
 
     vector<const item_def*> items;
-    item_list_on_square(items, item_link);
+    item_list_on_square(items, item_link, true);
+    ASSERT(items.size());
 
 #ifdef TOUCH_UI
     string prompt = "Pick up what? (<Enter> or tap header to pick up)";
@@ -1121,9 +1140,24 @@ string origin_desc(const item_def &item)
     return desc;
 }
 
+/*
+ * Pickup a single item stack at the given location link
+ *
+ * @param link The location link
+ * @param qty If 0, prompt for quantity of that item to pick up, if < 0,
+ *            pick up the entire stack, otherwise pick up qty of the item.
+ * @returns True if any item was picked up, false otherwise.
+*/
 bool pickup_single_item(int link, int qty)
 {
+    ASSERT(link != NON_ITEM);
+
     item_def* item = &mitm[link];
+    if (item_is_stationary(mitm[link]))
+    {
+        mpr("You can't pick that up.");
+        return false;
+    }
     if (item->base_type == OBJ_GOLD && !qty && !i_feel_safe()
         && !yesno("Are you sure you want to pick up this pile of gold now?",
                   true, 'n'))
@@ -1169,13 +1203,6 @@ bool pickup_single_item(int link, int qty)
         learned_something_new(HINT_FULL_INVENTORY);
         return false;
     }
-    else if (num == 0)
-    {
-        mpr("You can't carry that much weight.");
-        learned_something_new(HINT_FULL_INVENTORY);
-        return false;
-    }
-
     return true;
 }
 
@@ -1188,12 +1215,18 @@ bool player_on_single_stack()
         return mitm[o].link == NON_ITEM && mitm[o].quantity > 1;
 }
 
+/*
+ * Do the pickup command.
+ *
+ * @param partial_quantity If true, prompt for a quantity to pick up when
+ *                         picking up a single stack.
+*/
 void pickup(bool partial_quantity)
 {
     int keyin = 'x';
 
     int o = you.visible_igrd(you.pos());
-    const int num_items = _count_items(o);
+    const int num_items = count_movable_items(o);
 
     // Store last_pickup in case we need to restore it.
     // Then clear it to fill with items picked up.
@@ -1202,15 +1235,23 @@ void pickup(bool partial_quantity)
 
     if (o == NON_ITEM)
         mpr("There are no items here.");
+    else if (num_items == 0)
+        mpr("There are no items here that you can pick up.");
     else if (you.form == TRAN_ICE_BEAST && grd(you.pos()) == DNGN_DEEP_WATER)
         mpr("You can't reach the bottom while floating on water.");
-    else if (mitm[o].link == NON_ITEM)      // just one item?
+    // just one movable item?
+    else if (num_items == 1)
+    {
+        // Get the link to the movable item in the pile.
+        while (item_is_stationary(mitm[o]))
+            o = mitm[o].link;
         pickup_single_item(o, partial_quantity ? 0 : mitm[o].quantity);
+    }
     else if (Options.pickup_menu
              || Options.pickup_menu_limit
-                && num_items >= (Options.pickup_menu_limit < 0
-                                 ? Options.item_stack_summary_minimum
-                                 : Options.pickup_menu_limit))
+             && num_items >= (Options.pickup_menu_limit < 0
+                              ? Options.item_stack_summary_minimum
+                              : Options.pickup_menu_limit))
     {
         pickup_menu(o);
     }
@@ -1256,13 +1297,9 @@ void pickup(bool partial_quantity)
                 clear_item_pickup_flags(mitm[o]);
                 int result = move_item_to_player(o, num_to_take);
 
-                if (result == 0 || result == -1)
+                if (result == -1)
                 {
-                    if (result == 0)
-                        pickup_warning = "You can't carry that much weight.";
-                    else
-                        pickup_warning = "You can't carry that many items.";
-
+                    pickup_warning = "You can't carry that many items.";
                     mitm[o].flags = old_flags;
                 }
             }
@@ -1531,7 +1568,10 @@ void note_inscribe_item(item_def &item)
 }
 
 /*
- * Move the given item and quantity to the player's inventory
+ * Move the given item and quantity to the player's inventory.
+ *
+ * Returns 1 so pickup can continue if the pickup fails due to the item being
+ * stationary or not having enough runes to pick up the orb in zotdef.
  * @param obj The item index in mitm.
  * @param quant_got The quantity of this item to move.
  * @param quiet If true, most messages notifying the player of item pickup (or
@@ -1545,7 +1585,7 @@ int move_item_to_player(int obj, int quant_got, bool quiet)
 
     if (item_is_stationary(it))
     {
-        mpr("You cannot pick up the net that holds you!");
+        mpr("You can't pick that up.");
         // Fake a successful pickup (return 1), so we can continue to
         // pick up anything else that might be on this square.
         return 1;