Lunatic: move code in test/shadexfog.lua to engine.savePaletteDat() and complete it.

The function now writes out a full PALETTE.DAT: base balette, shade table and
translucency table.

git-svn-id: https://svn.eduke32.com/eduke32@4311 1a8010ca-5511-0410-912e-c29ae57300e0

polymer/eduke32/source/lunatic/engine.lua

@@ -226,5 +226,43 @@ function engine.nearcolor(r, g, b, lastokcol)
 end
 
 
+---------- Mapster32-only functions ----------
+
+if (ismapster32) then
+    local io = require("io")
+
+    ffi.cdef[[size_t fwrite(const void * restrict ptr, size_t size, size_t nmemb, void * restrict stream);]]
+
+    -- [ok, errmsg] = engine.savePaletteDat(filename [, palnum [, blendnum]])
+    function engine.savePaletteDat(filename, palnum, blendnum)
+        local sht = engine.getshadetab(palnum or 0)
+        local tab = engine.getblendtab(blendnum or 0)
+
+        if (sht == nil) then
+            return nil, "no shade table with number "..palnum
+        elseif (tab == nil) then
+            return nil, "no blending table with number "..blendnum
+        end
+
+        local f, errmsg = io.open(filename, "w+")
+        if (f == nil) then
+            return nil, errmsg
+        end
+
+        local n1 = ffi.C.fwrite(C.palette, 3, 256, f)
+        f:write("\032\000")  -- int16_t numshades
+        local n3 = ffi.C.fwrite(sht, 256, 32, f)
+        local n4 = ffi.C.fwrite(tab, 256, 256, f)
+
+        f:close()
+        if (n1 ~= 256 or n3 ~= 32 or n4 ~= 256) then
+            return nil, "failed writing enough data"
+        end
+
+        return true
+    end
+end
+
+
 -- Done!
 return engine

polymer/eduke32/source/lunatic/test/shadexfog.lua

@@ -196,40 +196,13 @@ local function create_base_shtab_2(basesht)
 end
 
 if (gv.LUNATIC_CLIENT == gv.LUNATIC_CLIENT_MAPSTER32) then
-    -- NOTE: It shouldn't be assumed that these will stay loadable in the future:
-    local ffi = require("ffi")
-    local io = require("io")
-
-    ffi.cdef[[size_t fwrite(const void * restrict ptr, size_t size, size_t nmemb, void * restrict stream);]]
-
-    function shadexfog.save(filename, palnum_or_sht)
-        local sht = type(palnum_or_sht)~="number" and palnum_or_sht
-            or engine.getshadetab(palnum_or_sht)
-        if (sht == nil) then
-            error("No such shade table")
+    -- Wrapper around engine.savePaletteDat() that errors on unexpected events.
+    function shadexfog.save(filename, palnum, blendnum)
+        local ok, errmsg = engine.savePaletteDat(filename, palnum, blendnum)
+        if (not ok) then
+            error(errmsg)
         end
-
-        local f, errmsg = io.open(filename, "w+")
-        if (f == nil) then
-            error(errmsg, 2)
-        end
-
-        -- XXX: ought to be in engine.lua
-        local basepal = ffi.new("uint8_t [256][3]")
-        for i=0,255 do
-            local r, g, b = engine.getrgb(i)
-            basepal[i][0], basepal[i][1], basepal[i][2] = r, g, b
-        end
-
-        local n1 = ffi.C.fwrite(basepal, 3, 256, f)
-        f:write("\032\000")
-        local n3 = ffi.C.fwrite(sht, 256, 32, f)
-
-        f:close()
-        if (n1 ~= 256 or n3 ~= 32) then
-            error("didn't fully write out palette file")
-        end
-        printf("Wrote base palette + shade table (but NOT transluc table) to '%s'", filename)
+        printf('Wrote base palette, shade and translucency tables to "%s"', filename)
     end
 end