Changes related to ray-collision, and luprex global variable stuff

luprex/cpp/core/world-accessor.cpp

@@ -1,6 +1,7 @@
 
 #include "world.hpp"
 #include "pprint.hpp"
+#include "serializelua.hpp"
 #include <cmath>
 
 static void tangible_getall(LuaCoreStack &LS0, LuaSlot list, const util::IdVector &idv) {
@@ -949,14 +950,7 @@ LuaDefine(global_set, "varname, value",
     "|lua identifier."
     "|"
     "|You can store global data using global.set, then you can"
-    "|retrieve it using global.get.  You can also retrieve data using"
-    "|gv.varname, which is just shorthand for global.get.  You may not"
-    "|store data using gv.varname=value, this yields the error 'Use "
-    "|global.set to store data in the global data table.'"
-    "|"
-    "|Values stored using global.set are transmitted to all"
-    "|connected clients immediately.  When a new client connects,"
-    "|he will receive all the global data."
+    "|retrieve it using global.get."
     "|"
     "|The global data table is not the same thing as the lua "
     "|environment table.  Trying to store data in the lua environment"
@@ -966,18 +960,16 @@ LuaDefine(global_set, "varname, value",
     "|global data table (using global.set) instead of in the lua"
     "|environment table."
     "|"
-    "|There are certain restrictions on the values that you store."
-    "|Only data that can be serialized according to doc(table.serialize)"
-    "|can be stored."
+    "|Data is stored in a serialized form.  The data is serialized"
+    "|at the moment you call global.set.  It is deserialized when you"
+    "|call global.get.  Therefore, each time you call global.get, you"
+    "|construct another copy of the value."
     "|"
-    "|When you store the value, it is immediately serialized and then"
-    "|deserialized again, and the deserialized copy is stored in the"
-    "|variable."
-    "|"
-//    "|When you call global.get, you obtain the copy.  Any attempt to"
-//    "|mutate the copy will fail with this lua error message: 'Tables"
-//    "|returned by global.get are immutable.'  This rule prevents'"
-//    "|aliasing between global data and other data structures."
+    "|The serialization routine can only serialize certain kinds of"
+    "|values.  For example, closures cannot be serialized at all."
+    "|Serializing a tangible serializes the tangible's ID, but"
+    "|none of the contents of the tangible.  See doc(table.serialize)"
+    "|for more information about what can and can't be serialized."
     "|") {
     LuaArg varname;
     LuaArg value;
@@ -990,8 +982,16 @@ LuaDefine(global_set, "varname, value",
         return LS.result();
     }
 
+    // Serialize the data.
+    StreamBuffer sb;
+    eng::string error = serialize_lua(LS, value, &sb);
+    if (!error.empty()) {
+        luaL_error(L, "%s", error.c_str());
+        return LS.result();
+    }
+
     World *w = World::fetch_global_pointer(L);
-    w->set_global(LS, gvar, value);
+    w->set_global(gvar, sb.view());
     return LS.result();
 }
 
@@ -1000,16 +1000,33 @@ LuaDefine(global_get, "varname",
     "|"
     "|See doc(global.set) for information on how to store global data."
     "|"
-    "|Do not mutate data returned by global.get: doing so will produce"
-    "|unpredictable results.  Instead, using global.set to mutate global"
-    "|variables."
+    "|Performance note: each time you call global.get, you deserialize the"
+    "|stored serialized version, constructing another copy of the data."
     "|") {
     LuaArg varname;
     LuaRet value;
-    LuaVar globaldb;
-    LuaDefStack LS(L, varname, value, globaldb);
-    LS.rawget(globaldb, LuaRegistry, "globaldb");
-    LS.rawget(value, globaldb, varname);
+    LuaDefStack LS(L, varname, value);
+    LS.set(value, LuaNil);
+
+    // Check the varname argument.
+    eng::string gvar = LS.ckstring(varname);
+    if (!sv::is_lua_id(gvar)) {
+        luaL_error(L, "variable name must be a valid lua identifier: %s", gvar.c_str());
+        return LS.result();
+    }
+
+    // Fetch the serialized blob.
+    World *w = World::fetch_global_pointer(L);
+    std::string_view data = w->get_global(gvar);
+    if (data.empty()) return LS.result();
+
+    // Deserialize the blob.
+    StreamBuffer sb(data);
+    eng::string error = deserialize_lua(LS, value, &sb);
+    if (!error.empty()) {
+        luaL_error(L, "%s", error.c_str());
+        return LS.result();
+    }
     return LS.result();
 }
 
@@ -1022,8 +1039,8 @@ LuaDefine(global_once, "varname",
     "|") {
     LuaArg varname;
     LuaRet result;
-    LuaVar globaldb, flag;
-    LuaDefStack LS(L, varname, flag, result, globaldb);
+    LuaDefStack LS(L, varname, result);
+    LS.set(result, false);
 
     // Check the varname argument.
     eng::string gvar = LS.ckstring(varname);
@@ -1033,17 +1050,12 @@ LuaDefine(global_once, "varname",
     }
     gvar += ":once";
 
-    LS.rawget(globaldb, LuaRegistry, "globaldb");
-    LS.rawget(flag, globaldb, gvar);
-
-    if (!LS.isnil(flag)) {
-        LS.set(result, false);
-        return LS.result();
-    }
-
-    LS.set(result, true);
     World *w = World::fetch_global_pointer(L);
-    w->set_global(LS, gvar, result);
+    LS.set(result, false);
+    if (w->get_global(gvar).empty()) {
+        LS.set(result, true);
+        w->set_global(gvar, "x");
+    }
     return LS.result();
 }
 
@@ -1055,8 +1067,7 @@ LuaDefine(global_clearonce, "varname",
     "|uses global.set under the covers."
     "|") {
     LuaArg varname;
-    LuaVar null;
-    LuaDefStack LS(L, varname, null);
+    LuaDefStack LS(L, varname);
 
     // Check the varname argument.
     eng::string gvar = LS.ckstring(varname);
@@ -1066,8 +1077,7 @@ LuaDefine(global_clearonce, "varname",
     }
     gvar += ":once";
 
-    LS.set(null, LuaNil);
     World *w = World::fetch_global_pointer(L);
-    w->set_global(LS, gvar, null);
+    w->set_global(gvar, "");
     return LS.result();
 }