Fix: default lregion exclusion area occupied real space on the map

The intuitive behavior of des.levregion or des.teleport_region when
"exclude" is left unspecified is that there is no exclusion area.
However, this wasn't actually the case: since l_get_lregion defaulted
the exclusion area to (0,0,0,0) and exclude_islev to 0, this meant that
the 0,0 space on the map would always be excluded from regions. In cases
where a region was specified with its inclusion area constrained to the
0,0 space of the map, this would create a "Couldn't place lregion"
impossible message.

This fixes that issue by defaulting the exclusion area to (-1,-1,-1,-1),
and if the exclusion area is left unspecified, forces exclude_islev=1.
This means that the exclusion zone will be outside the walkable space of
the level where it can't cause any problems.

If a level designer puts negative coordinates in their inclusion or
exclusion parameters, this might not work correctly, but negative region
coordinates aren't currently used anywhere and probably shouldn't be
supported anyway.

diff --git a/doc/lua.adoc b/doc/lua.adoc
index 1e5628bb6d697c3cae3c5ad48c5a6de6a5d6d7aa..7fc5ea4677ccbaa9338b76c44d05cb24617c319b 100644 (file)
--- a/doc/lua.adoc
+++ b/doc/lua.adoc
@@ -896,7 +896,7 @@ Example:
 Example:
 
  des.teleport_region({ region = { x1,y1, x2,y2} });
- des.teleport_region({ region = { x1,y1, x2,y2}, region_islev = 1, exclude = { x1,y1, x2,y2}, exclude_islen = 1, dir = "up" });
+ des.teleport_region({ region = { x1,y1, x2,y2}, region_islev = 1, exclude = { x1,y1, x2,y2}, exclude_islev = 1, dir = "up" });
 
 
 === terrain

diff --git a/src/sp_lev.c b/src/sp_lev.c
index e067f34e4dc2c24bda8acf4866512e1626076452..916e713a444c24672bc37d8638f23a55f8aa1354 100644 (file)
--- a/src/sp_lev.c
+++ b/src/sp_lev.c
@@ -5887,7 +5887,8 @@ levregion_add(lev_region* lregion)
 /* get params from topmost lua hash:
    - region = {x1,y1,x2,y2}
    - exclude = {x1,y1,x2,y2} (optional)
-   - region_islev=true, exclude_idlev=true (optional) */
+   - region_islev=true, exclude_islev=true (optional)
+   - negative x and y are invalid */
 static void
 l_get_lregion(lua_State *L, lev_region *tmplregion)
 {
@@ -5899,7 +5900,7 @@ l_get_lregion(lua_State *L, lev_region *tmplregion)
     tmplregion->inarea.x2 = x2;
     tmplregion->inarea.y2 = y2;
 
-    x1 = y1 = x2 = y2 = 0;
+    x1 = y1 = x2 = y2 = -1;
     get_table_region(L, "exclude", &x1, &y1, &x2, &y2, TRUE);
     tmplregion->delarea.x1 = x1;
     tmplregion->delarea.y1 = y1;
@@ -5908,6 +5909,13 @@ l_get_lregion(lua_State *L, lev_region *tmplregion)
 
     tmplregion->in_islev = get_table_boolean_opt(L, "region_islev", 0);
     tmplregion->del_islev = get_table_boolean_opt(L, "exclude_islev", 0);
+
+    /* if x1 is still negative, exclude wasn't specified, so we should treat it
+     * as if there is no exclude region at all. Force exclude_islev to true so
+     * the -1,-1,-1,-1 region is safely off the map and won't interfere with
+     * branch or portal placement. */
+    if (x1 < 0)
+        tmplregion->del_islev = TRUE;
 }
 
 /* teleport_region({ region = { x1,y1, x2,y2} }); */