diff --git a/config/menus_edit.cfg b/config/menus_edit.cfg
index 23b289ef..c4f5cd50 100644
--- a/config/menus_edit.cfg
+++ b/config/menus_edit.cfg
@@ -104,10 +104,12 @@ menuitem "Edit arches..." [ showmenu "Edit arches" ]
 menuitem "" -1
 menuitemslider "Slope axis: " 0 1 "$__slopeaxis"  1 ["West to East (X)" "North to South (Y)"] [ __slopeaxis = $arg1 ]
 menuitemslider "Slope increment: " 0 5 "$__slopeinc"  1 ["downwards 3" "downwards 2" "downwards 1" "upwards 1" "upwards 2" "upwards 3"] [ __slopeinc = $arg1 ]
-menuitem "\t[ Place slope ]" [ __setundoarch ; heightfield 0; push i (at "-3 -2 -1 1 2 3" $__slopeinc) ; slope (if $__slopeaxis 0 $i) (if $__slopeaxis $i 0) ; pop i ; 0]
+menuitem "\t[ Place slope ]" [ __setundoarch ; heightfield 0; push i (at "3 2 1 -1 -2 -3" $__slopeinc) ; slope (if $__slopeaxis 0 $i) (if $__slopeaxis $i 0) ; pop i ; 0]
 menuitem "" -1
 menuitem "Clear heightfielding" [ solid 0; slope 0 0 ]
 menuitem "Undo last placed arch or slope" [ __undoarch ; -1 ]
+menuitemcheckbox  "Automatically enlarge selections after placing arches and slopes" "$enlargearchslopeselections" [ enlargearchslopeselections $arg1 ]
+menuitem "Enlarge selections now" enlargevdeltaselections
 menuitem "" -1
 menuitemslider "Stairs axis: " 0 1 "$__stairaxis"  1 ["West to East (X)" "North to South (Y)"] [ __stairaxis = $arg1 ]
 menuitemslider "Step width: " 0 5 "$__stairwidth"  1 ["downwards 3" "downwards 2" "downwards 1" "upwards 1" "upwards 2" "upwards 3"] [ __stairwidth = $arg1 ]
diff --git a/config/scripts.cfg b/config/scripts.cfg
index 358af16a..86870c47 100644
--- a/config/scripts.cfg
+++ b/config/scripts.cfg
@@ -349,6 +349,32 @@ const selectall [
     select 2 2 (- (powf 2 (mapsize)) 4) (- (powf 2 (mapsize)) 4)
 ]
 
+// push and pop selection sets
+const pushselections [
+    if (listlen (selx)) [
+        push selsets ""
+        selectionwalk [ ] [ selsets = (concat $selsets "; addselection" $sw_cursel) ]
+        push popselections (concat "resetselections" (pop selsets) "; pop popselections")
+    ][
+        echo no selction
+    ]
+]
+tempalias popselections [ echo no selections stored ]
+
+// enlarge selections after slope or arch placement to change all vdelta values (when enlargearchslopeselections is 0)
+const enlargevdeltaselections [
+    if (listlen (selx)) [
+        push selsets ""
+        push i (if $numargs $arg1 1)
+        selectionwalk [ ] [ selsets = (concat $selsets $sw_cursel) ]
+        resetselections
+        looplist (pop selsets) [x y xs ys] [ addselection $x $y (+ $xs $i) (+ $ys $i) ]
+        pop i
+    ][
+        echo no selction
+    ]
+]
+
 //    /expandselection 1    // makes the current selection bigger by 1 cube on all sides
 const expandselection [
   if $numargs [
diff --git a/source/src/editing.cpp b/source/src/editing.cpp
index 5cecd829..53d4e361 100644
--- a/source/src/editing.cpp
+++ b/source/src/editing.cpp
@@ -944,6 +944,8 @@ void setvdelta(int *delta)
 }
 COMMANDN(vdelta, setvdelta, "i");
 
+VARP(enlargearchslopeselections, 0, 0, 1); // "1" is classic behaviour
+
 const int MAXARCHVERT = 50;
 int archverts[MAXARCHVERT][MAXARCHVERT];
 bool archvinit = false;
@@ -982,7 +984,8 @@ void arch(int *sidedelta)
         if(sel.ys>MAXARCHVERT) sel.ys = MAXARCHVERT;
         int *averts = sel.xs > sel.ys ? &archverts[sel.xs-1][0] : &archverts[sel.ys-1][0];
         addmsg(SV_EDITARCH, "ri5v", sel.x, sel.y, sel.xs, sel.ys, *sidedelta, MAXARCHVERT, averts);
-        archxy(*sidedelta, averts, sel); // (changes xs and ys)
+        archxy(*sidedelta, averts, sel);
+        if(!enlargearchslopeselections) { sel.xs--; sel.ys--; }
     }
 }
 COMMAND(arch, "i");
@@ -1006,6 +1009,7 @@ void slope(int *xd, int *yd)
         block &sel = sels[i];
         addmsg(SV_EDITXY, "ri7", EDITXY_SLOPE, sel.x, sel.y, sel.xs, sel.ys, *xd, *yd);
         slopexy(*xd, *yd, sel); // (changes xs and ys)
+        if(!enlargearchslopeselections) { sel.xs--; sel.ys--; }
     }
 }
 COMMAND(slope, "ii");
@@ -1044,6 +1048,7 @@ void perlin(int *scale, int *seed, int *psize)
         sel.xs++;
         sel.ys++;
         remipmore(sel);
+        if(!enlargearchslopeselections) { sel.xs--; sel.ys--; }
     }
 }
 COMMAND(perlin, "iii");