Lunatic: add example toggling forcefield wall to test.lua.

git-svn-id: https://svn.eduke32.com/eduke32@4224 1a8010ca-5511-0410-912e-c29ae57300e0

polymer/eduke32/source/lunatic/doc/lunatic.txt

@@ -566,10 +566,12 @@ spr.cstat = CS.TRANS1 + CS.BLOCK
 ----------
 one could proceed as follows for the sake of example:
 
-* `spr.cstatbits:set(CS.TRANS2)`, make the sprite 66% translucent now
-* `spr.cstatbits:flip(CS.BLOCK + CS.HITSCAN)`, make it hitscan-sensitive but
-  not blocking
-* `spr.cstatbits:test(CS.FLIP_BITMASK)`, check whether it is flipped (no)
+[source]
+----------
+spr.cstatbits:set(CS.TRANS2)  -- make the sprite 66% translucent now
+spr.cstatbits:flip(CS.BLOCK + CS.HITSCAN)  -- make it hitscan-sensitive and non-blocking
+local isflipped = spr.cstatbits:test(CS.FLIP_BITMASK)  -- is it x- or y-flipped? (no)
+----------
 ==========
 
 Engine-side composites

polymer/eduke32/source/lunatic/test.lua

@@ -18,6 +18,8 @@ local hitscan = hitscan
 
 local assert, error, print, tostring = assert, error, print, tostring
 
+local D = require("CON.DEFS")
+
 print('---=== ELua Test script ===---')
 
 local function printf(fmt, ...)
@@ -108,6 +110,24 @@ gameevent
     end
 }
 
+gameevent
+{
+    "JUMP",
+
+    function()
+        print("tweaking forcefield with lotag 34 (E2L1)")
+
+        for w=0,gv.numwalls-1 do
+            local wal = wall[w]
+            if (wal.overpicnum == D.W_FORCEFIELD or wal.overpicnum == D.W_FORCEFIELD+1) then
+                if (wal.lotag==34) then
+                    wal.cstat = wal.cstatbits:test(85) and 0 or 85
+                end
+            end
+        end
+    end
+}
+
 local unsafe = pcall(function() string.UNSAFE=true; end)
 
 checkfail("tostring = nil", "attempt to write into the global environment")
@@ -252,7 +272,6 @@ gameevent
 }
 --]]
 
-local D = require("CON.DEFS")
 local WEAPON = gv.WEAPON
 
 -- Bad hack to test out pitch/roll: EVENT_GAME is discouraged from Lunatic.