public Template(string tName, Location initial, List<Location> locs, List<Transition> transits, string localDecls)
{
name = tName;
InitialLocation = initial;
Locations = locs;
Transitions = transits;
localDeclarations = localDecls;
}
public Location(Location caller)
{
id = caller.id + "a";
y = caller.y + Constants.LabelOffsetY * 2;
x = Constants.LabelOffsetX * 10;
Label = new Label{
content = "1",
kind = "exponentialrate",
y = y,
x = caller.x + Constants.LabelOffsetX * 10 - 70
};
}
public Transition (Location from, Location to, List<Label> labl, int xOffset = 0)
{
source = from;
target = to;
for (int i = 0; i < labl.Count; i++)
{
var tmp = labl[i];
tmp.SetCords(from, i * Constants.LabelOffsetY);
labels.Add(tmp);
}
if (xOffset != 0)
{
nails.Add(new Nail(){x = xOffset, y = (from.y + to.y) / 2});
}
}
public void addErrorLocation()
{
// add extra error location for each template
foreach (var t in templates)
{
// make location
Location errorLoc = new Location();
errorLoc.x = -400;
errorLoc.y = 200;
errorLoc.name = "error";
errorLoc.id = Constants.errorLocId; // arbitrary id set high so as to not interfere with "regular" locs
t.Locations.Add(errorLoc);
}
}
public Template getTemplate(XElement xel)
{
Template t = new Template(xel);
t.InitialLocation.id = xel.Element("init").Attribute("ref").Value;
// store name object from XML
t.name = (string)xel.Element("name");
// store information about locations from UPPAAL model in objects from XML
foreach (var locs in xel.Descendants("location"))
{
Location l = new Location();
l.id = (string)locs.Attribute("id");
l.name = (string)locs.Element("name");
l.Guid = idCount.ToString();
var tr = locs.Element("urgent");
l.Urgent = tr != null;
idCount++;
XElement xele = locs.Element("label");
if (xele != null)
{
int xCoord = Convert.ToInt32(xele.Attribute("x").Value);
int yCoord = Convert.ToInt32(xele.Attribute("y").Value);
Label invariant = new Label { kind = xele.Attribute("kind").Value, content = (string)xele.Value, x = xCoord, y = yCoord };
l.Label = invariant;
}
try
{
// load pc number
Regex regex = new Regex(@"pc(\d+)");
Match match = regex.Match(l.name);
if (match.Success)
{
l.pc = match.Value.Replace("pc", "");
}
}
catch (Exception ex)
{
// yeah.. this should probably be handled more eloquently..
l.pc = "None";
} //TODO fix fault template
l.x = Convert.ToInt32(locs.Attribute("x").Value);
l.y = Convert.ToInt32(locs.Attribute("y").Value);
t.Locations.Add(l);
}
// store information about transitions from UPPAAL model in objects from XML
List<Transition> transitions = new List<Transition>();
foreach (var trans in xel.Descendants("transition"))
{
Transition srcDstPair = new Transition();
srcDstPair.source.id = (string)trans.Element("source").Attribute("ref");
srcDstPair.target.id = (string)trans.Element("target").Attribute("ref");
// add guards
srcDstPair.grds = getGuards(trans);
// add selections
srcDstPair.sels = getSelections(trans);
// add updates
srcDstPair.asms = getAssignments(trans);
// add synchronizations
srcDstPair.syncs = getSyncs(trans);
// add nails
srcDstPair.nails = getNails(trans);
transitions.Add(srcDstPair);
}
t.Transitions = transitions;
return t;
}
public Transition (Location from, Location to)
{
source = from;
target = to;
}
public Transition ()
{
source = new Location();
target = new Location();
}
public Location NextLocation(Location current)
{
var orderedLocs = Locations.OrderBy(x => x.inst.pc).ToList();
foreach (var loc in orderedLocs)
{
if (loc.inst.pc > current.inst.pc)
{
return loc;
}
}
throw new KeyNotFoundException();
}
private Location addExceptionLoc(Location waiter, int catchIndex, List<string> instArg){
string methodName = instArg[2].Split('.').Last();
string methodClassName = instArg[2].Split('.').First();
if (!JParser.ClassNames.Contains(methodClassName))
{
return null;
}
var excepLoc = new Location(waiter);
excepLoc.Urgent = true;
if (methodName == "<init>")
{
methodName = methodClassName;
}
int classId = classSelf.catchPCs[catchIndex];
Transitions.Add(new Transition(waiter, excepLoc,
makeLabels("guy",
"exceptionOccurred == true",
classId != -1 ? "osp_inc(), t = 0" : "osp = 0, t = 0",
String.Format("c{0}?", methodClassName + "_" + methodName))));
Transitions.Add(new Transition(excepLoc, PCToLocation(classId),
makeLabels("y", String.Format("c{0}!", name))));
return excepLoc;
}
private List<Transition>InvokeStatic(Location caller, Location waiter, Location next)
{
bool ret = caller.inst.instArgs[1] != "void";
var objRef = caller.name.Contains("invokespecial") ? 1 : 0;
string methodName = caller.inst.instArgs[2].Split('.').Last();
string methodClassName = caller.inst.instArgs[2].Split('.').First();
if (methodName == "<init>")
{
methodName = methodClassName;
}
var param = caller.inst.instArgs.Skip(3).Where(p => p != "()" && p != "(" && p != ")").ToList();
bool included = JParser.ClassNames.Contains(methodClassName);
var res = new List<Transition>();
var call = new List<Label>()
{
new Label
{
content = "t == 1", kind = "guard"
}
};
var wait = new List<Label>();
if (included)
{
call.Add(new Label
{
content = String.Format("osp_dec({0}), t = 0, par0 = os[osp]", param.Count + objRef),
kind = "assignment"
});
call.Add(new Label
{
content = String.Format("c{0}!", methodClassName + "_" + methodName),
kind = "synchronisation"
});
wait.Add(new Label
{
content = String.Format("c{0}?", methodClassName + "_" + methodName),
kind = "synchronisation"
});
wait.Add(new Label
{
content = "!exceptionOccurred", kind = "guard"
});
}
else
{
call.Add(new Label
{
content = String.Format("osp_dec({0}), t = 0", param.Count + objRef),
kind = "assignment"
});
// remove exponential label from non-implemented method call locations
waiter.Label = new Label() { kind = "invariant", content = "t <= 5"};
wait.Add(new Label
{
content = "t == 5", kind = "guard"
});
}
if (ret)
{
wait.Add(new Label
{
content = "t = 0, os[osp] = par0, osp_inc()", kind = "assignment"
});
}
else
{
wait.Add(new Label
{
content = "t = 0", kind = "assignment"
});
}
res.Add(new Transition(caller, waiter, call));
res.Add(new Transition(waiter, next, wait));
return res;
}
public Template(List<string> method, JClass self, int catchIndex)
{
classSelf = self;
name = self.Name + "_" + JClass.FirstNonKeyword(method.First());
Locations = ResolveLocations(method);
// instruction switch case
ResolveCode(catchIndex);
localDeclarations = @"const int os_size = 10;
const int locs_size = 10;
int os[os_size];
int osp = 0;
int locs[locs_size];
void osp_inc(){
if (osp >= os_size - 1){
opstack_fault = true;
return;
}
osp++;
return;
}
void osp_dec(int i){
if (osp < i){
opstack_fault = true;
return;
}
osp -= i;
return;
}
bool ifcmpme(){
if (osp > 1){
return os[osp-2] >= os[osp - 1];
}
return false;
}
bool ifcmpeq(){
if (osp > 1){
return os[osp-2] == os[osp - 1];
}
return false;
}
bool ifcmpge(){
if (osp > 1){
return os[osp - 2] >= os[osp - 1] ;
}
return false;
}
bool ifcmpne(){
if (osp > 1){
return os[osp - 2] != os[osp - 1] ;
}
return false;
}
bool ifeq(){
if (osp > 0){
return os[osp - 1] == 0;
}
return false;
}";
InitialLocation = Locations.First();
}
//Magic happens here!
private void ResolveCode(int catchIndex)
{
var timeGuard = "t == 1";
var newLocs = new List<Location>();
List<Label> labels = new List<Label>();
foreach (var loc in Locations)
{
//TODO maybe move to switch with instArg
if (loc.inst.pc == -1)
{
// special case for main
if (loc.name == "main")
{
loc.Urgent = true;
labels = new List<Label>()
{
new Label
{
// TODO this should probably be fixed..
content = String.Format("t = 0", 0),
kind = "assignment"
}
};
Transitions.Add(new Transition(loc, PCToLocation(0), labels));
continue; //clean up later
}
labels = new List<Label>()
{
new Label
{
content = timeGuard, kind = "guard"
},
new Label
{
content = String.Format("c{0}?", name),
kind = "synchronisation"
},
new Label
{
// TODO this should probably be fixed..
content = String.Format("locs[{0}] = par{0}, t = 0", 0),
kind = "assignment"
}
};
Transitions.Add(new Transition(loc, PCToLocation(0), labels));
continue;
}
var instArg = loc.inst.instArgs;
switch (instArg[0])
{
case "aload":
/* aload load a refernce from locals into the opstack
* the opstack counter osp is incremented as the opstack grows.
* Opstack: .. -> .. , locals[n]
*/
labels = new List<Label>()
{
new Label
{
content = timeGuard, kind = "guard"
},
new Label
{
content = String.Format(" osp_inc(), os[osp - 1] = locs[{0}], t = 0", instArg[1]),
kind = "assignment"
}
};
Transitions.Add(new Transition(loc, NextLocation(loc), labels)); //TODO is +1 allways true?
break;
case "arraylength":
/* arrays are represented as an object on the heap
* the first field (index 0) is used for the lenght
* making it identical to getfield 0
* Opstack: .. , ref -> .. , lenght
*/
labels = new List<Label>()
{
new Label
{
content = timeGuard, kind = "guard"
},
new Label
{
content = "os[osp] = H(os[osp]), t = 0", kind = "assignment"
}
};
Transitions.Add(new Transition(loc, NextLocation(loc), labels));
break;
case "getstatic":
/* get a static field value of a class,
* where the field is identified by field reference in the constant pool index
* Opstack: .. -> .. , CP[n]
*/
labels = new List<Label>()
{
new Label
{
content = timeGuard, kind = "guard"
},
new Label
{
content = String.Format("osp_inc(), os[osp-1] = H(cp{0}), t = 0",
CP.Add(String.Join(" ", instArg.Skip(1)))),
kind = "assignment"
}
};
Transitions.Add(new Transition(loc, NextLocation(loc), labels));
break;
case "putfield":
Transitions.Add(new Transition(loc, NextLocation(loc), makeLabels("gu",
timeGuard,
String.Format("osp_dec(2), setH(os[osp] + {0}, os[osp + 1])",
classSelf.Fields.FindIndex(x => x.Split(' ').Last() == instArg[1].Split('.').Last()) + 1))));
break;
case "getfield":
Transitions.Add(new Transition(loc, NextLocation(loc), makeLabels("gu",
timeGuard,
String.Format("os[osp - 1] = H(os[osp - 1] + {0})",
classSelf.Fields.FindIndex(x => x.Split(' ').Last() == instArg[1].Split('.').Last()) + 1))));
//lamda compares the name of: public int <name>; with class.<name>
break;
case "bipush":
case "iconst":
/* Pushes a constant value to the opstack
* Opstack: .. -> .. , n
*/
labels = new List<Label>()
{
new Label
{
content = timeGuard, kind = "guard"
},
new Label
{
content = String.Format("osp_inc(), os[osp - 1] = {0}, t = 0", instArg[1]),
kind = "assignment"
}
};
Transitions.Add(new Transition(loc, NextLocation(loc), labels));
break;
case "ifcmpeq":
labels = new List<Label>()
{
new Label
{
content = timeGuard + " && ifcmpeq()", kind = "guard"
},
new Label
{
content = "osp_dec(2), t = 0", kind = "assignment"
}
};
Transitions.Add(new Transition(loc, PCToLocation(loc.inst.pc + Convert.ToInt32(instArg[1])), labels, -50));
labels = new List<Label>()
{
new Label
{
content = timeGuard + " && !ifcmpeq()", kind = "guard"
},
new Label
{
content = "opstack_fault = osp < 2 ? true : opstack_fault, osp_dec(2), t = 0", kind = "assignment"
}
};
Transitions.Add(new Transition(loc, NextLocation(loc), labels));
break;
case "ifcmpme":
/* if greather or eq
* Opstack: .. ,value1, value2 -> ..
*/
labels = new List<Label>()
{
new Label
{
content = timeGuard + " && ifcmpme()", kind = "guard"
},
new Label
{
content = "osp_dec(2), t = 0", kind = "assignment"
}
};
Transitions.Add(new Transition(loc, PCToLocation(loc.inst.pc + Convert.ToInt32(instArg[1])), labels, -50));
labels = new List<Label>()
{
new Label
{
content = timeGuard + " && !ifcmpme()", kind = "guard"
},
new Label
{
content = "opstack_fault = osp < 2 ? true : opstack_fault, osp_dec(2), t = 0", kind = "assignment"
},
new Label
{
content = timeGuard, kind = "guard"
}
};
Transitions.Add(new Transition(loc, NextLocation(loc), labels));
break;
case "ifeq":
/* if top element equal to 0
* Opstack: .. , value1 -> ..
*/
labels = new List<Label>()
{
new Label
{
content = timeGuard + " && ifeq()", kind = "guard"
},
new Label
{
content = "osp_dec(1), t = 0", kind = "assignment"
}
};
Transitions.Add(new Transition(loc, PCToLocation(loc.inst.pc + Convert.ToInt32(instArg[1])), labels, -50));
labels = new List<Label>()
{
new Label
{
content = timeGuard + " && !ifeq()", kind = "guard"
},
new Label
{
content = "opstack_fault = osp < 1 ? true : opstack_fault, osp_dec(1), t = 0", kind = "assignment"
}
};
Transitions.Add(new Transition(loc, NextLocation(loc), labels));
break;
case "new":
labels = new List<Label>()
{
new Label
{
content = timeGuard, kind = "guard"
},
new Label
{
content = String.Format("osp_inc(), os[osp-1] = alocNew({0}), t = 0",
JParser.getClassID(instArg[1])),
kind = "assignment"
}
};
Transitions.Add(new Transition(loc, NextLocation(loc), labels));
break;
case "invokevirtual":
var waiterV = new Location(loc);
var param = loc.inst.instArgs.Skip(3).Where(p => p != "()" && p != "(" && p != ")").ToList();
labels = makeLabels("gyu",
timeGuard,
"cVirtual!",
String.Format("osp_dec({0}), par0 = os[osp], meID = {1}",
param.Count + 1,
JParser.GetMethodIndex(instArg[2].Replace(".", "_")))
);
newLocs.Add(waiterV);
Transitions.Add(new Transition(loc, waiterV, labels));
var virReturn = "t = 0";
if (loc.inst.instArgs[1] != "void")
{
virReturn += ", os[osp] = par0, osp_inc()";
}
labels = makeLabels("yu", "cVirtual?", virReturn);
Transitions.Add(new Transition(waiterV, NextLocation(loc), labels));
newLocs.Add(addExceptionLoc(waiterV, catchIndex, instArg));
break;
case "invokespecial":
case "invokestatic":
var waiterS = new Location(loc);
Transitions.AddRange(InvokeStatic(loc, waiterS, NextLocation(loc)));
newLocs.Add(waiterS);
newLocs.Add(addExceptionLoc(waiterS, catchIndex, instArg));
break;
case "ldc":
labels = new List<Label>()
{
new Label
{
content = timeGuard, kind = "guard"
},
new Label
{
content = String.Format("osp_inc(), os[osp-1] = cp{0}, t = 0",
CP.Add(String.Join(" ", instArg.Skip(1)))),
kind = "assignment"
},
new Label
{
content = timeGuard, kind = "guard"
}
};
Transitions.Add(new Transition(loc, NextLocation(loc), labels));
break;
case "ireturn":
case "return":
labels = new List<Label>()
{
new Label
{
content = timeGuard, kind = "guard"
},
new Label
{
content = String.Format("c{0}!", name),
kind = "synchronisation"
},
new Label
{
content = timeGuard, kind = "guard"
}
};
if (instArg[0] == "ireturn")
{
labels.Add(new Label
{
content = String.Format("osp_dec(1), par0 = os[osp], osp = 0, t = 0"),
kind = "assignment"
});
}
else
{
labels.Add(new Label
{
content = String.Format("osp = 0, t = 0"),
kind = "assignment"
});
}
if (name.Split('_').Last() == "main")
{
var endLoc = new Location(loc);
endLoc.name = "Done";
endLoc.Label = new Label
{
content = "1",
kind = "exponentialrate"
};
newLocs.Add(endLoc);
labels.RemoveAll(l => l.kind == "assignment");
Transitions.Add(new Transition(loc, endLoc, labels));
break;
}
Transitions.Add(new Transition(loc, PCToLocation(-1), labels, -100));
break;
case "dup":
labels = new List<Label>()
{
new Label
{
content = "osp_dec(1), osp_inc(), osp_inc(), os[osp - 1] = os[osp - 2]",
kind = "assignment"
},
new Label
{
content = timeGuard, kind = "guard"
}
};
Transitions.Add(new Transition(loc, NextLocation(loc), labels));
break;
case "sipush":
labels = new List<Label>()
{
new Label
{
content = string.Format("osp_inc(), os[osp] = {0}", instArg[1]),
kind = "assignment"
},
new Label
{
content = timeGuard, kind = "guard"
}
};
Transitions.Add(new Transition(loc, NextLocation(loc), labels));
break;
case "iload":
labels = new List<Label>()
{
new Label
{
content = string.Format("osp_inc(), os[osp - 1] = locs[{0}]", instArg[1]),
kind = "assignment"
},
new Label
{
content = timeGuard, kind = "guard"
}
};
Transitions.Add(new Transition(loc, NextLocation(loc), labels));
break;
case "istore":
// fall through to astore because Kristian wanted to save space..
// lol, it does the same as astore from our perspetive anyway
case "astore":
labels = new List<Label>()
{
new Label
{
content = string.Format("osp_dec(1), locs[{0}] = os[osp]", instArg[1]),
kind = "assignment"
},
new Label
{
content = timeGuard, kind = "guard"
}
};
Transitions.Add(new Transition(loc, NextLocation(loc), labels));
break;
case "ifcmpge":
var labelsNoJump = new List<Label>()
{
new Label
{
content = string.Format("{0} && !ifcmpge()", timeGuard),
kind = "guard"
},
new Label
{
content = "osp_dec(2)",
kind = "assignment"
}
};
var labelsJump = new List<Label>()
{
new Label
{
content = string.Format("{0} && ifcmpge()", timeGuard),
kind = "guard"
},
new Label
{
content = "osp_dec(2)",
kind = "assignment"
}
};
// edge to next location
Transitions.Add(new Transition(loc, NextLocation(loc), labelsNoJump));
// edge to jump destination
int absoluteAddress = loc.inst.pc + Convert.ToInt32(instArg[1]);
Location jumpLoc = PCToLocation(absoluteAddress);
Transitions.Add(new Transition(loc, jumpLoc, labelsJump, -50));
break;
case "athrow":
var throwLoc = new Location(loc);
throwLoc.Urgent = true;
newLocs.Add(throwLoc);
labels = Template.makeLabels("gu",
timeGuard,
"exceptionOccurred = true"
);
Transitions.Add(new Transition(loc, throwLoc, labels));
labels = Template.makeLabels("y",
String.Format("c{0}!", name));
Transitions.Add(new Transition(throwLoc, PCToLocation(-1), labels));
break;
case "goto":
labels = new List<Label>()
{
new Label
{
content = timeGuard, kind = "guard"
}
};
Transitions.Add(new Transition(loc, PCToLocation(loc.inst.pc + Convert.ToInt32(instArg[1])), labels, -50));
break;
case "ifcmpne":
List<Label> labJump = makeLabels("gu",
timeGuard + " && ifcmpne()",
"osp_dec(2)");
List<Label> labNoJump = makeLabels("gu",
timeGuard + " && !ifcmpne",
"osp_dec(2)");
Transitions.Add(new Transition(loc, PCToLocation(loc.inst.pc + Convert.ToInt32(instArg[1])), labJump, -50));
Transitions.Add(new Transition(loc, NextLocation(loc), labNoJump, -50));
break;
case "putstatic":
labels = new List<Label>()
{
new Label
{
content = timeGuard, kind = "guard"
},
new Label
{
content = String.Format("osp_dec(1), setH(cp{0}, os[osp]), t = 0",
CP.Add(String.Join(" ", instArg.Skip(1)))),
kind = "assignment"
}
};
Transitions.Add(new Transition(loc, NextLocation(loc), labels));
break;
case "iadd":
labels = new List<Label>()
{
new Label
{
content = timeGuard, kind = "guard"
},
new Label
{
content = "osp_dec(2), osp_inc(), os[osp - 1] = os[osp - 1] + os[osp], t = 0",
kind = "assignment"
}
};
Transitions.Add(new Transition(loc, NextLocation(loc), labels));
break;
case "pop":
labels = new List<Label>()
{
new Label
{
content = timeGuard, kind = "guard"
},
new Label
{
content = "osp_dec(1), t = 0",
kind = "assignment"
}
};
Transitions.Add(new Transition(loc, NextLocation(loc), labels));
break;
default:
labels = new List<Label>()
{
new Label
{
content = timeGuard, kind = "guard"
}
};
Transitions.Add(new Transition(loc, NextLocation(loc), labels));
loc.name += "___NOT_IMPLEMENTED___NOT_IMPLEMENTED___NOT_IMPLEMENTED";
//throw new System.NotImplementedException(instArg[0]);
break;
}
}
newLocs.RemoveAll(x => x == null);
Locations.AddRange(newLocs);
}
//The CTOR for the Virtual template.
public Template(List<string> method){
name = "Virtual";
//init Loc
var initLoc = new Location("Invoke", 0 ,0);
InitialLocation = initLoc;
Locations.Add(initLoc);
//resolve loc
var SignaChecks = new List<string>();
var resolveLoc = new Location("Resolver", 0, 100);
resolveLoc.Urgent = true;
Locations.Add(resolveLoc);
Transitions.Add(new Transition(initLoc, resolveLoc,
makeLabels("yu", "cVirtual?", "clID = H(par0)")
));
//Error loc
var errorLoc = new Location("Error", 200, 50);
Locations.Add(errorLoc);
Transitions.Add(new Transition(resolveLoc, errorLoc,
makeLabels("g","clID == 0")
));
var returnerLoc = new Location("Returner", -100, 300);
returnerLoc.Urgent = true;
Locations.Add(returnerLoc);
Transitions.Add(new Transition(returnerLoc, initLoc, makeLabels("y", "cVirtual!")));
//Method locations
for (int i = 0; i < method.Count; i++)
{
var mLoc = new Location(method[i], i*200, 200);
var sigCheck = String.Format("signature(clID, {0}, {1})",
JParser.GetMethodIndex(method[i]).ToString(),
JParser.getClassID(mLoc.name.Split('_').First()));
Locations.Add(mLoc);
Transitions.Add(new Transition(resolveLoc, mLoc, makeLabels("gy",
sigCheck,
String.Format("c{0}!", mLoc.name)
)));
Transitions.Add(new Transition(mLoc, returnerLoc,
makeLabels("y", String.Format("c{0}?", mLoc.name))));
SignaChecks.Add(sigCheck);
}
Transitions.Add(new Transition(resolveLoc, resolveLoc, makeLabels("gu",
String.Format("clID != 0 && !({0})",String.Join(" || ", SignaChecks)),
"clID = classHierarchy(clID)"
)));
}
public static bool isReachable(Location l1, Location l2)
{
// 8 bits for a single byte
for (int i = 0; i < 7; i++)
{
try
{
int n1 = Int32.Parse(l1.pc.ToString());
int n2 = Int32.Parse(l2.pc.ToString());
if (((n1) ^ Convert.ToInt32(Math.Pow(2, i))) == n2)
{
return true;
}
}
catch (Exception ex)
{
// to catch "None"s
return false;
}
}
return false;
}
public void calculateReachableLocations()
{
// calculate which states are reachable by a single bit flip
foreach (Location l in Locations)
{
foreach (Location lNext in Locations)
{
if ((l.id != lNext.id && isReachable(l, lNext)))// && !(reachableLocs.ContainsKey(l) || reachableLocs.ContainsKey(lNext)))
{
l.reachableLocs.Add(lNext);
}
}
}
// insert new errror loc
var errLoc = new Location("error", -500, Locations.OrderByDescending(l => l.y).First().y / 2);
Locations.Add(errLoc);
foreach (Location l in Locations)
{
if (l.pc == null)
{
continue;
}
for (int i = l.reachableLocs.Count; i < 8 ; i++)
{
l.reachableLocs.Add(errLoc);
}
}
}
public void SetCords(Location loc, int offset)
{
x = Constants.LabelOffsetX;
y = Convert.ToInt32(loc.y) + offset;
}