fix explosions breaking old replays

src/tools/prefs.mac.mm

@@ -38,6 +38,11 @@ NSDictionary* prefsToRecord = @{
 	@"UIScale": @(kFloat),
 	@"UIScaleMap": @(kFloat)
 };
+// Some legacy preferences influenced RNG and must be
+// known by replays
+NSDictionary* prefsToReplay = @{
+	@"DrawTerrainFrills": @(kBool)
+};
 
 bool prefsLoaded = false;
 
@@ -133,11 +138,17 @@ static bool load_prefs(std::istream& istream) {
 
 		std::string key = line.substr(0, key_end + 1), val = line.substr(val_beg);
 		NSString* pref_key = [NSString stringWithUTF8String: key.c_str()];
+		NSInteger type;
 		// Skip obsolete preferences from legacy replays
 		if([prefsToRecord valueForKey: pref_key] == nil){
-			continue;
+			if([prefsToReplay valueForKey: pref_key] == nil){
+				continue;
+			}else{
+				type = [prefsToReplay[pref_key] integerValue];
+			}
+		}else{
+			type = [prefsToRecord[pref_key] integerValue];
 		}
-		NSInteger type = [prefsToRecord[pref_key] integerValue];
 		switch((int)type) {
 			case kBool:
 				if(val == "true") set_pref(key, true);