buildings: make windows masterable like other demandable furnishings

docs/changelog.txt

@@ -74,6 +74,7 @@ Template for new versions:
 - `buildingplan`: fix roller material estimate asking for one chain per tile instead of one chain total
 - `buildingplan`: fix "Unlink all" only unlinking some mechanisms (or crashing) when freeing mechanisms from the building
 - `tiletypes`: remove plants (including trees) rooted on a tile that is painted into something that cannot host them, so cleared ground no longer regrows floating trees
+- Fixed gem and glass windows being unable to be made part of a room; they are the only buildings nobles can demand that could not be, whether the window or the room is placed first
 - `timestream`: deal properly with units who have breathing difficulties
 - `stocks`: overlay now resets scroll position when collapsing categories so the item list is no longer left blank and unscrollable
 - Fixed persistent site data API (``dfhack.persistent.saveSiteData``/``getSiteData``) failing on newly reclaimed fortresses until the first save

library/modules/Buildings.cpp

@@ -33,6 +33,7 @@ distribution.
 #include "TileTypes.h"
 #include "MiscUtils.h"
 #include "DataDefs.h"
+#include "VTableInterpose.h"
 
 #include "modules/Buildings.h"
 #include "modules/Maps.h"
@@ -61,6 +62,8 @@ distribution.
 #include "df/building_water_wheelst.h"
 #include "df/building_weaponst.h"
 #include "df/building_wellst.h"
+#include "df/building_window_gemst.h"
+#include "df/building_window_glassst.h"
 #include "df/building_workshopst.h"
 #include "df/buildingitemst.h"
 #include "df/buildings_other_id.h"
@@ -134,13 +137,43 @@ static df::building_extents_type *getExtentTile(const df::building::T_room &room
  */
 bool buildings_do_onupdate = false;
 
+/*
+ * Mitigation for a DF bug: gem and glass windows are the only buildings that
+ * nobles can demand in their rooms whose masterablebuilding (canMakeRoom)
+ * vmethod returns false, so a window built inside an existing room is linked
+ * to it while a room designated over an existing window is not. Interpose the
+ * vmethod on the two concrete subclasses; the abstract building_windowst
+ * vtable cannot be hooked.
+ */
+struct window_gem_masterable_hook : df::building_window_gemst {
+    typedef df::building_window_gemst interpose_base;
+    DEFINE_VMETHOD_INTERPOSE(bool, canMakeRoom, ())
+    {
+        return true;
+    }
+};
+IMPLEMENT_VMETHOD_INTERPOSE(window_gem_masterable_hook, canMakeRoom);
+
+struct window_glass_masterable_hook : df::building_window_glassst {
+    typedef df::building_window_glassst interpose_base;
+    DEFINE_VMETHOD_INTERPOSE(bool, canMakeRoom, ())
+    {
+        return true;
+    }
+};
+IMPLEMENT_VMETHOD_INTERPOSE(window_glass_masterable_hook, canMakeRoom);
+
 void buildings_onStateChange(color_ostream &out, state_change_event event)
 {
     switch (event) {
     case SC_MAP_LOADED:
+        INTERPOSE_HOOK(window_gem_masterable_hook, canMakeRoom).apply();
+        INTERPOSE_HOOK(window_glass_masterable_hook, canMakeRoom).apply();
         buildings_do_onupdate = true;
         break;
     case SC_MAP_UNLOADED:
+        INTERPOSE_HOOK(window_gem_masterable_hook, canMakeRoom).remove();
+        INTERPOSE_HOOK(window_glass_masterable_hook, canMakeRoom).remove();
         buildings_do_onupdate = false;
         break;
     default:

test/modules/buildings_fortress.lua

@@ -0,0 +1,92 @@
+config.target = 'core'
+config.mode = 'fortress'
+
+local function contains(vec, value)
+    for _,entry in ipairs(vec) do
+        if entry == value then return true end
+    end
+    return false
+end
+
+local function construct_window_in_zone(window_type)
+    for _,zone in ipairs(df.global.world.buildings.other.ANY_ZONE) do
+        if zone.room.extents then
+            for y = zone.y1, zone.y2 do
+                for x = zone.x1, zone.x2 do
+                    local pos = xyz2pos(x, y, zone.z)
+                    if not dfhack.buildings.findAtTile(pos) then
+                        local bld = dfhack.buildings.constructBuilding{
+                            pos=pos,
+                            type=window_type,
+                            filters=dfhack.buildings.getFiltersByType(
+                                {}, window_type, -1, -1),
+                        }
+                        if bld then return bld, zone end
+                    end
+                end
+            end
+        end
+    end
+end
+
+local function expect_window_linked(window_type)
+    local bld, zone = construct_window_in_zone(window_type)
+    expect.ne(nil, bld, 'could not find a zone tile suitable for a window')
+    if not bld then return end
+    dfhack.with_finalize(
+        function() dfhack.buildings.deconstruct(bld) end,
+        function()
+            expect.true_(contains(bld.relations, zone))
+            expect.true_(contains(zone.contained_buildings, bld))
+        end)
+end
+
+function test.constructed_gem_window_is_linked_to_zone()
+    expect_window_linked(df.building_type.WindowGem)
+end
+
+function test.constructed_glass_window_is_linked_to_zone()
+    expect_window_linked(df.building_type.WindowGlass)
+end
+
+local function expect_zoned_window_linked(window_type)
+    local bld, _ = construct_window_in_zone(window_type)
+    expect.ne(nil, bld, 'could not find a tile suitable for a window')
+    if not bld then return end
+    dfhack.with_finalize(
+        function() dfhack.buildings.deconstruct(bld) end,
+        function()
+            local pos = xyz2pos(bld.centerx, bld.centery, bld.z)
+            local extents = df.reinterpret_cast(df.building_extents_type,
+                                                df.new('uint8_t', 1))
+            extents[0] = 1
+            local zone, err = dfhack.buildings.constructBuilding{
+                type=df.building_type.Civzone,
+                subtype=df.civzone_type.Bedroom,
+                abstract=true,
+                pos=pos, width=1, height=1,
+                fields={
+                    assigned_unit_id=-1,
+                    room={x=pos.x, y=pos.y, width=1, height=1,
+                          extents=extents},
+                },
+            }
+            expect.ne(nil, zone, 'could not place zone over window: ' ..
+                                 tostring(err))
+            if not zone then return end
+            dfhack.with_finalize(
+                function() dfhack.buildings.deconstruct(zone) end,
+                function()
+                    expect.true_(contains(bld.relations, zone))
+                    expect.true_(contains(zone.contained_buildings, bld))
+                end)
+        end)
+end
+
+function test.zoned_gem_window_is_linked_to_zone()
+    expect_zoned_window_linked(df.building_type.WindowGem)
+end
+
+function test.zoned_glass_window_is_linked_to_zone()
+    expect_zoned_window_linked(df.building_type.WindowGlass)
+end