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  • Optimal communication pattern to update subscribers

    - by hpc
    What is the optimal way to update the subscriber's local model on changes C on a central model M? ( M + C - M_c) The update can be done by the following methods: Publish the updated model M_c to all subscribers. Drawback: if the model is big in contrast to the change it results in much more data to be communicated. Publish change C to all subscribes. The subscribers will then update their local model in the same way as the server does. Drawback: The client needs to know the business logic to update the model in the same way as the server. It must be assured that the subscribed model stays equal to the central model. Calculate the delta (or patch) of the change (M_c - M = D_c) and transfer the delta. Drawback: This requires that calculating and applying the delta (M + D_c = M_c) is an cheap/easy operation. If a client newly subscribes it must be initialized. This involves sending the current model M. So method 1 is always required. Think of playing chess as a concrete example: Subscribers send moves and want to see the latest chess board state. The server checks validity of the move and applies it to the chess board. The server can then send the updated chessboard (method 1) or just send the move (method 2) or send the delta (method 3): remove piece on field D4, put tower on field D8.

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  • Validation and Error Generation when using the Data Mapper Pattern

    - by AndyPerlitch
    I am working on saving state of an object to a database using the data mapper pattern, but I am looking for suggestions/guidance on the validation and error message generation step (step 4 below). Here are the general steps as I see them for doing this: (1) The data mapper is used to get current info (assoc array) about the object in db: +=====================================================+ | person_id | name | favorite_color | age | +=====================================================+ | 1 | Andy | Green | 24 | +-----------------------------------------------------+ mapper returns associative array, eg. Person_Mapper::getPersonById($id) : $person_row = array( 'person_id' => 1, 'name' => 'Andy', 'favorite_color' => 'Green', 'age' => '24', ); (2) the Person object constructor takes this array as an argument, populating its fields. class Person { protected $person_id; protected $name; protected $favorite_color; protected $age; function __construct(array $person_row) { $this->person_id = $person_row['person_id']; $this->name = $person_row['name']; $this->favorite_color = $person_row['favorite_color']; $this->age = $person_row['age']; } // getters and setters... public function toArray() { return array( 'person_id' => $this->person_id, 'name' => $this->name, 'favorite_color' => $this->favorite_color, 'age' => $this->age, ); } } (3a) (GET request) Inputs of an HTML form that is used to change info about the person is populated using Person::getters <form> <input type="text" name="name" value="<?=$person->getName()?>" /> <input type="text" name="favorite_color" value="<?=$person->getFavColor()?>" /> <input type="text" name="age" value="<?=$person->getAge()?>" /> </form> (3b) (POST request) Person object is altered with the POST data using Person::setters $person->setName($_POST['name']); $person->setFavColor($_POST['favorite_color']); $person->setAge($_POST['age']); *(4) Validation and error message generation on a per-field basis - Should this take place in the person object or the person mapper object? - Should data be validated BEFORE being placed into fields of the person object? (5) Data mapper saves the person object (updates row in the database): $person_mapper->savePerson($person); // the savePerson method uses $person->toArray() // to get data in a more digestible format for the // db gateway used by person_mapper Any guidance, suggestions, criticism, or name-calling would be greatly appreciated.

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  • Implementing a "state-machine" logic for methods required by an object in C++

    - by user827992
    What I have: 1 hypothetical object/class + other classes and related methods that gives me functionality. What I want: linking this object to 0 to N methods in realtime on request when an event is triggered Each event is related to a single method or a class, so a single event does not necessarily mean "connect this 1 method only" but can also mean "connect all the methods from that class or a group of methods" Avoiding linked lists because I have to browse the entire list to know what methods are linked, because this does not ensure me that the linked methods are kept in a particular order (let's say an alphabetic order by their names or classes), and also because this involve a massive amount of pointers usage. Example: I have an object Employee Jon, Jon acquires knowledge and forgets things pretty easily, so his skills may vary during a period of time, I'm responsible for what Jon can add or remove from his CV, how can I implement this logic?

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  • Identity Map Pattern and the Entity Framework

    - by nikolaosk
    This is going to be the seventh post of a series of posts regarding ASP.Net and the Entity Framework and how we can use Entity Framework to access our datastore. You can find the first one here , the second one here and the third one here , the fourth one here , the fifth one here and the sixth one here . I have a post regarding ASP.Net and EntityDataSource. You can read it here .I have 3 more posts on Profiling Entity Framework applications. You can have a look at them here , here and here . In...(read more)

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  • Can an object oriented program be seen as a Finite State Machine?

    - by Peretz
    This might be a philosophical/fundamental question, but I just want to clarify it. In my understanding a Finite State Machine is a way of modeling a system in which the system's output will not only depend on the current inputs, but also the current state of the system. Additionally, as the name suggests it, a finite state machine can be segmented in a finite N number of states with its respective state and behavior. If this is correct, shouldn't every single object with data and function members be a state in our object oriented model, making any object oriented design a finite state machine? If that is not the interpretation of a FSM in object design, what exactly people mean when they implement a FSM in software? am I missing something? Thanks

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  • Deferred contexts and inheriting state from the immediate context

    - by dreijer
    I took my first stab at using deferred contexts in DirectX 11 today. Basically, I created my deferred context using CreateDeferredContext() and then drew a simple triangle strip with it. Early on in my test application, I call OMSetRenderTargets() on the immediate context in order to render to the swap chain's back buffer. Now, after having read the documentation on MSDN about deferred contexts, I assumed that calling ExecuteCommandList() on the immediate context would execute all of the deferred commands as "an extension" to the commands that had already been executed on the immediate context, i.e. the triangle strip I rendered in the deferred context would be rendered to the swap chain's back buffer. That didn't seem to be the case, however. Instead, I had to manually pull out the immediate context's render target (using OMGetRenderTargets()) and then set it on the deferred context with OMSetRenderTargets(). Am I doing something wrong or is that the way deferred contexts work?

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  • Resolving a Forward Declaration Issue Involving a State Machine in C++

    - by hypersonicninja
    I've recently returned to C++ development after a hiatus, and have a question regarding implementation of the State Design Pattern. I'm using the vanilla pattern, exactly as per the GoF book. My problem is that the state machine itself is based on some hardware used as part of an embedded system - so the design is fixed and can't be changed. This results in a circular dependency between two of the states (in particular), and I'm trying to resolve this. Here's the simplified code (note that I tried to resolve this by using headers as usual but still had problems - I've omitted them in this code snippet): #include <iostream> #include <memory> using namespace std; class Context { public: friend class State; Context() { } private: State* m_state; }; class State { public: State() { } virtual void Trigger1() = 0; virtual void Trigger2() = 0; }; class LLT : public State { public: LLT() { } void Trigger1() { new DH(); } void Trigger2() { new DL(); } }; class ALL : public State { public: ALL() { } void Trigger1() { new LLT(); } void Trigger2() { new DH(); } }; // DL needs to 'know' about DH. class DL : public State { public: DL() { } void Trigger1() { new ALL(); } void Trigger2() { new DH(); } }; class HLT : public State { public: HLT() { } void Trigger1() { new DH(); } void Trigger2() { new DL(); } }; class AHL : public State { public: AHL() { } void Trigger1() { new DH(); } void Trigger2() { new HLT(); } }; // DH needs to 'know' about DL. class DH : public State { public: DH () { } void Trigger1() { new AHL(); } void Trigger2() { new DL(); } }; int main() { auto_ptr<LLT> llt (new LLT); auto_ptr<ALL> all (new ALL); auto_ptr<DL> dl (new DL); auto_ptr<HLT> hlt (new HLT); auto_ptr<AHL> ahl (new AHL); auto_ptr<DH> dh (new DH); return 0; } The problem is basically that in the State Pattern, state transitions are made by invoking the the ChangeState method in the Context class, which invokes the constructor of the next state. Because of the circular dependency, I can't invoke the constructor because it's not possible to pre-define both of the constructors of the 'problem' states. I had a look at this article, and the template method which seemed to be the ideal solution - but it doesn't compile and my knowledge of templates is a rather limited... The other idea I had is to try and introduce a Helper class to the subclassed states, via multiple inheritance, to see if it's possible to specify the base class's constructor and have a reference to the state subclasse's constructor. But I think that was rather ambitious... Finally, would a direct implmentation of the Factory Method Design Pattern be the best way to resolve the entire problem?

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  • State Changes in a Component Based Architecture [closed]

    - by Maxem
    I'm currently working on a game and using the naive component based architecture thingie (Entities are a bag of components, entity.Update() calls Update on each updateable component), while the addition of new features is really simple, it makes a few things really difficult: a) multithreading / currency b) networking c) unit testing. Multithreading / Concurrency is difficult because I basically have to do poor mans concurrency (running the entity updates in separate threads while locking only stuff that crashes (like lists) and ignoring the staleness of read state (some states are already updated, others aren't)) Networking: There are no explicit state changes that I could efficiently push over the net. Unit testing: All updates may or may not conflict, so automated testing is at least awkward. I was thinking about these issues a bit and would like your input on these changes / idea: Switch from the naive cba to a cba with sub systems that work on lists of components Make all state changes explicit Combine 1 and 2 :p Example world update: statePostProcessing.Wait() // ensure that post processing has finished Apply(postProcessedState) state = new StateBag() Concurrently( () => LifeCycleSubSystem.Update(state), // populates the state bag () => MovementSubSystem.Update(state), // populates the state bag .... }) statePostProcessing = Future(() => PostProcess(state)) statePostProcessing.Start() // Tick is finished, the post processing happens in the background So basically the changes are (consistently) based on the data for the last tick; the post processing can a) generate network packages and b) fix conflicts / remove useless changes (example: entity has been destroyed - ignore movement etc.). EDIT: To clarify the granularity of the state changes: If I save these post processed state bags and apply them to an empty world, I see exactly what has happened in the game these state bags originated from - "Free" replay capability. EDIT2: I guess I should have used the term Event instead of State Change and point out that I kind of want to use the Event Sourcing pattern

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  • Is MVC a Design Pattern or Architectural pattern

    - by JCasso
    According to Sun and Msdn it is a design pattern. According to Wikipedia it is an architectural pattern In comparison to design patterns, architectural patterns are larger in scale. (Wikipedia - Architectural pattern) Or it is an architectural pattern that also has a design pattern ? Which one is true ?

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  • Is a finite state machine an appropriate solution for this situation?

    - by user1936
    I was writing some test code as an example where I had a washing machine class. It has a door state that should be open or closed, and also a running state, either on or off. I want to prevent the running state from changing from 'off' to 'on' when the door is 'open', and also prevent the door from being set to 'open' while the machine is 'on'. I have this functionality rigged up with a bunch of if statements. It feels inelegant and it could quickly turn into spaghetti code if I want to add another state that puts additional conditions on the changes of other states. I wonder, is a finite state machine a solution for this situation? Would it simplify adding states and defining valid transitions?

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  • Validation with State Pattern for Multi-Page Forms in ASP.NET

    - by philrabin
    I'm trying to implement the state pattern for a multi-page registration form. The data on each page will be accumulated and stored in a session object. Should validation (including service layer calls to the DB) occur on the page level or inside each state class? In other words, should the concrete implementation of IState be concerned with the validation or should it be given a fully populated and valid object? See "EmptyFormState" class below: namespace Example { public class Registrar { private readonly IState formEmptyState; private readonly IState baseInformationComplete; public RegistrarSessionData RegistrarSessionData { get; set;} public Registrar() { RegistrarSessionData = new RegistrarSessionData(); formEmptyState = new EmptyFormState(this); baseInformationComplete = new BasicInfoCompleteState(this); State = formEmptyState; } public IState State { get; set; } public void SubmitData(RegistrarSessionData data) { State.SubmitData(data); } public void ProceedToNextStep() { State.ProceedToNextStep(); } } //actual data stored in the session //to be populated by page public class RegistrarSessionData { public string FirstName { get; set; } public string LastName { get; set; } //will include values of all 4 forms } //State Interface public interface IState { void SubmitData(RegistrarSessionData data); void ProceedToNextStep(); } //Concrete implementation of IState //Beginning state - no data public class EmptyFormState : IState { private readonly Registrar registrar; public EmptyFormState(Registrar registrar) { this.registrar = registrar; } public void SubmitData(RegistrarSessionData data) { //Should Validation occur here? //Should each state object contain a validation class? (IValidator ?) //Should this throw an exception? } public void ProceedToNextStep() { registrar.State = new BasicInfoCompleteState(registrar); } } //Next step, will have 4 in total public class BasicInfoCompleteState : IState { private readonly Registrar registrar; public BasicInfoCompleteState(Registrar registrar) { this.registrar = registrar; } public void SubmitData(RegistrarSessionData data) { //etc } public void ProceedToNextStep() { //etc } } }

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  • Do Ruby/Rails state machines exist that execute event transitions when a state change occurs?

    - by Bryan
    Hello All, Hopefully this isn't a silly question and I'm just not overlooking something in Ruby/Rails state machines (AASM, Transitions, AlterEgo, etc). From what I can tell, these state machine implementations operate on the preface that an event will get fired and the appropriate transition for that event will be triggered based on the old and new state. However, they don't seem to work the other way; say a user wants to change state from 'created' to 'assigned' and have the correct transition occur (rather than firing the event that causes the current state to be transitioned to the new state). Essentially, I want the user to be able to select a new state from a select box of available states and have the appropriate transition, guards, success callbacks, etc executed. Does anyone know if the existing state machine implementations support this?

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  • System State Backups using NTbackup fail with error 0x800423f4 (relating to volume shadow copy)

    - by Paul Zimmerman
    We have a Windows Server 2003 R2 running Service Pack 2. It is a domain controller (Global Catalog) and our main internal DNS server. We run a System State backup of the machine to back up Active Directory information and save the backup to a different server. This server has a single drive (C:), and we do have Shadow Copies enabled for the volume (which are completing successfully). The System State Backup is now failing with the following listed in the backup logs: Volume shadow copy creation: Attempt 1. "Event Log Writer" has reported an error 0x800423f4. This is part of System State. The backup cannot continue. Error returned while creating the volume shadow copy:800423f4 Aborting Backup. The operation did not successfully complete. When doing a vssadmin list writers, we sometimes get the following reported for the Event Log Writer (other times it says that it is in the state of "[1] Stable" with "No error"): Writer name: 'Event Log Writer' Writer Id: {eee8c692-67ed-4250-8d86-390603070d00} Writer Instance Id: {c7194e96-868a-49e5-ba99-89b61977753c} State: [8] Failed Last error: Retryable error We have tried disabling the event log service via the registry, rebooting, deleting the event log files from the drive, then re-enabling the service via the registry and rebooting, but this didn't seem to solve the issue. We also get an error message when in the event viewer when trying to open the log for the "File Replication Service" of "Unable to complete the operation on 'File Replication Service'. The security descriptor structure is invalid." I have searched the error via Google and tried a number of different things, but nothing has seemed to help. Any suggestions on what we might try to get the Event Log Writer to behave would be greatly appreciated!

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  • Alternative to Game State System?

    - by Ricket
    As far as I can tell, most games have some sort of "game state system" which switches between the different game states; these might be things like "Intro", "MainMenu", "CharacterSelect", "Loading", and "Game". On the one hand, it totally makes sense to separate these into a state system. After all, they are disparate and would otherwise need to be in a large switch statement, which is obviously messy; and they certainly are well represented by a state system. But at the same time, I look at the "Game" state and wonder if there's something wrong about this state system approach. Because it's like the elephant in the room; it's HUGE and obvious but nobody questions the game state system approach. It seems silly to me that "Game" is put on the same level as "Main Menu". Yet there isn't a way to break up the "Game" state. Is a game state system the best way to go? Is there some different, better technique to managing, well, the "game state"? Is it okay to have an intro state which draws a movie and listens for enter, and then a loading state which loops on the resource manager, and then the game state which does practically everything? Doesn't this seem sort of unbalanced to you, too? Am I missing something?

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  • C# - Coding a nested stateflow diagram

    - by weberc2
    I have the following state diagram. I know how to make a simple state machine that transitions between non-nested states; however, I don't know how to transition between nested states. Could someone explain how to do this at an appropriately high level (i.e., you don't need to write the code for me--unless you're feeling particularly generous :P). State Diagram [EDIT: The bottom "A", "C", and "E" should be "B", "D", and "F" respectively; sorry!] What I know how to do public class MyState : State // State enumeration { public static MyState A = new MyState("State A"); public static MyState B = new MyState("State B"); public static MyState C = new MyState("State C"); public static MyState D = new MyState("State D"); public static MyState E = new MyState("State E"); public static MyState F = new MyState("State F"); public static MyState NEUT = new MyState("Neutral"); public static MyState P = new MyState("P"); protected MyState(string name) : base(name) { } } public class MyEvent : Event // Event enumeration { public static MyEvent X_POS = new MyEvent("X+"); public static MyEvent X_NEG = new MyEvent("X-"); public static MyEvent Y_POS = new MyEvent("Y+"); public static MyEvent Y_NEG = new MyEvent("Y-"); protected MyEvent(string name) : base(name) { } } public class MyStateMachine : StateMachine<MyState, MyEvent> // State Machine implementation { public MyStateMachine() : base(MyState.P) // MyState.P = initial state { // Set up the transition table // P this.addTransition(MYState.P, MyState.NEUT, MyEvent.Y_NEG); // NEUTRAL this.addTransition(MyState.NEUT, MyState.P, MyEvent.Y_POS); this.addTransition(MyState.NEUT, MyState.A, MyEvent.Y_NEG); this.addTransition(MyState.NEUT, MyState.B, MyEvent.Y_POS); this.addTransition(MyState.NEUT, MyState.C, MyEvent.Y_NEG); this.addTransition(MyState.NEUT, MyState.D, MyEvent.Y_POS); this.addTransition(MyState.NEUT, MyState.E, MyEvent.Y_NEG); this.addTransition(MyState.NEUT, MyState.F, MyEvent.Y_POS); // A this.addTransition(MyState.A, MyState.NEUT, MyEvent.Y_POS); // B this.addTransition(MyState.B, MyState.NEUT, MyEvent.Y_NEG); // C this.addTransition(MyState.C, MyState.NEUT, MyEvent.Y_POS); // D this.addTransition(MyState.D, MyState.NEUT, MyEvent.Y_NEG); // E this.addTransition(MyState.E, MyState.NEUT, MyEvent.Y_POS); // F this.addTransition(MyState.F, MyState.NEUT, MyEvent.Y_NEG); } public void move(MyEvent eevent) { try { this.moveNext(eevent); } catch (Exception e) { } } }

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  • Unable to change the value of the variable

    - by Legend
    I'm using a discrete event simulator called ns-2 that was built using Tcl and C++. I was trying to write some code in TCL: set ns [new Simulator] set state 0 $ns at 0.0 "puts \"At 0.0 value of state is: $state\"" $ns at 1.0 "changeVal" $ns at 2.0 "puts \"At 2.0 values of state is: $state\"" proc changeVal {} { global state global ns $ns at-now "set state [expr $state+1]" puts "Changed value of state to $state" } $ns run Here's the output: At 0.0 value of state is: 0 Changed value of state to 0 At 2.0 values of state is: 0 The value of state does not seem to change. I am not sure if I am doing something wrong in using TCL. Anyone has an idea as to what might be going wrong here? EDIT: Thanks for the help. Actually, ns-2 is something over which I do not have much control (unless I recompile the simulator itself). I tried out the suggestions and here's the output: for the code: set ns [new Simulator] set state 0 $ns at 0.0 "puts \"At 0.0 value of state is: $state\"" $ns at 1.0 "changeVal" $ns at 9.0 "puts \"At 2.0 values of state is: $state\"" proc changeVal {} { global ns set ::state [expr {$::state+1}] $ns at-now "puts \"At [$ns now] changed value of state to $::state\"" } $ns run the output is: At 0.0 value of state is: 0 At 1 changed value of state to 1 At 2.0 values of state is: 0 And for the code: set ns [new Simulator] set state 0 $ns at 0.0 "puts \"At 0.0 value of state is: $state\"" $ns at 1.0 "changeVal" $ns at 9.0 "puts \"At 2.0 values of state is: $state\"" proc changeVal {} { global ns set ::state [expr {$::state+1}] $ns at 1.0 {puts "At 1.0 values of state is: $::state"} } $ns run the output is: At 0.0 value of state is: 0 At 1.0 values of state is: 1 At 2.0 values of state is: 0 Doesn't seem to work... Not sure if its a problem with ns2 or my code...

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  • Data-driven animation states

    - by user8363
    I'm trying to handle animations in a 2D game engine hobby project, without hard-coding them. Hard coding animation states seems like a common but very strange phenomenon, to me. A little background: I'm working with an entity system where components are bags of data and subsystems act upon them. I chose to use a polling system to update animation states. With animation states I mean: "walking_left", "running_left", "walking_right", "shooting", ... My idea to handle animations was to design it as a data driven model. Data could be stored in an xml file, a rdbms, ... And could be loaded at the start of a game / level/ ... This way you can easily edit animations and transitions without having to go change the code everywhere in your game. As an example I made an xml draft of the data definitions I had in mind. One very important piece of data would simply be the description of an animation. An animation would have a unique id (a descriptive name). It would hold a reference id to an image (the sprite sheet it uses, because different animations may use different sprite sheets). The frames per second to run the animation on. The "replay" here defines if an animation should be run once or infinitely. Then I defined a list of rectangles as frames. <animation id='WIZARD_WALK_LEFT'> <image id='WIZARD_WALKING' /> <fps>50</fps> <replay>true</replay> <frames> <rectangle> <x>0</x> <y>0</y> <width>45</width> <height>45</height> </rectangle> <rectangle> <x>45</x> <y>0</y> <width>45</width> <height>45</height> </rectangle> </frames> </animation> Animation data would be loaded and held in an animation resource pool and referenced by game entities that are using it. It would be treated as a resource like an image, a sound, a texture, ... The second piece of data to define would be a state machine to handle animation states and transitions. This defines each state a game entity can be in, which states it can transition to and what triggers that state change. This state machine would differ from entity to entity. Because a bird might have states "walking" and "flying" while a human would only have the state "walking". However it could be shared by different entities because multiple humans will probably have the same states (especially when you define some common NPCs like monsters, etc). Additionally an orc might have the same states as a human. Just to demonstrate that this state definition might be shared but only by a select group of game entities. <state id='IDLE'> <event trigger='LEFT_DOWN' goto='MOVING_LEFT' /> <event trigger='RIGHT_DOWN' goto='MOVING_RIGHT' /> </state> <state id='MOVING_LEFT'> <event trigger='LEFT_UP' goto='IDLE' /> <event trigger='RIGHT_DOWN' goto='MOVING_RIGHT' /> </state> <state id='MOVING_RIGHT'> <event trigger='RIGHT_UP' goto='IDLE' /> <event trigger='LEFT_DOWN' goto='MOVING_LEFT' /> </state> These states can be handled by a polling system. Each game tick it grabs the current state of a game entity and checks all triggers. If a condition is met it changes the entity's state to the "goto" state. The last part I was struggling with was how to bind animation data and animation states to an entity. The most logical approach seemed to me to add a pointer to the state machine data an entity uses and to define for each state in that machine what animation it uses. Here is an xml example how I would define the animation behavior and graphical representation of some common entities in a game, by addressing animation state and animation data id. Note that both "wizard" and "orc" have the same animation states but a different animation. Also, a different animation could mean a different sprite sheet, or even a different sequence of animations (an animation could be longer or shorter). <entity name="wizard"> <state id="IDLE" animation="WIZARD_IDLE" /> <state id="MOVING_LEFT" animation="WIZARD_WALK_LEFT" /> </entity> <entity name="orc"> <state id="IDLE" animation="ORC_IDLE" /> <state id="MOVING_LEFT" animation="ORC_WALK_LEFT" /> </entity> When the entity is being created it would add a list of states with state machine data and an animation data reference. In the future I would use the entity system to build whole entities by defining components in a similar xml format. -- This is what I have come up with after some research. However I had some trouble getting my head around it, so I was hoping op some feedback. Is there something here what doesn't make sense, or is there a better way to handle these things? I grasped the idea of iterating through frames but I'm having trouble to take it a step further and this is my attempt to do that.

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  • Query Object Pattern (Design Pattern)

    - by The Elite Gentleman
    Hi Guys, I need to implement a Query Object Pattern in Java for my customizable search interface (of a webapp I'm writing). Does anybody know where I can get an example/tutorial of Query Object Pattern (Martin Fowler's QoP)? Thanks in Advance ADDITION How to add a Query Pattern to an existing DAO pattern?

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  • ASP.NET 2.0 in Virtual Trying to Use SQL State Server

    - by user251660
    We have IIS 6 running on a W2003 Server. The root web site is running a v1.1 site. Under this site we have a virtual running a v2.0 site (with a separate application pool). The web.config for the root site is using SQL as its state server and has a 1.1 SQL state server database installed. The 2.0 virtual web.config does not need state and its web.config has no reference to a state server. When we attempt to call the virtual we receive this error message. "Unable to use SQL Server because ASP.NET version 2.0 Session State is not installed on the SQL server. Please install ASP.NET Session State SQL Server version 2.0 or above. This issue is currently only occurring on one web server. The rest are able to run the 2.0 virtual application. I also notice that if we call the 2.0 virtual with the IP address it does not generate the error, however if we call it with the host header name it generates the error (this behavior is only on the 1 web server with the error, all the others can be called with either the ip or host header without error). As an additional note the root and virtual are running with SSL. My theory is that the virtual 2.0 application is inheriting the 1.1 web.config state server entry from the root and when it looks at the state server it sees it as a 1.1 version and reports the error that it needs a 2.0 state server. I however cannot understand why the other servers are not behaving in this matter. All of the servers are on the same OS service pack as well as the same version of .net framework. Any ideas? Thanks

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  • MS Dynamic CRM 4.0 serviceappointment closed state javascript event

    - by Jeroen
    Hi, I need to do the following: In Crm, you have serviceappointments (serviceactivities). 1 appointment can have a state, ( like arrived, pending, closed, ... ). When i save the form (onsave event), It should catch if the form is putted closed state and then it should do something. I can get the state easily: alert(crmForm.all.statuscode.DataValue) I hanged this onto an onsave event. But when i put a serviceappointment into closed state, it first calls the onsave event with previous state and then puts it in closed state. Is it possible to catch if it's putted in closed state?

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  • Java RegEx Pattern not matching (works in .NET)

    - by CDSO1
    Below is an example that is producing an exception in Java (and not matching the input). Perhaps I misunderstood the JavaDoc, but it looks like it should work. Using the same pattern and input in C# will produce a match. import java.util.regex.Matcher; import java.util.regex.Pattern; public class Main { public static void main(String[] args) { String pattern = "aspx\\?uid=([^']*)"; Pattern p = Pattern.compile(pattern); Matcher m = p.matcher("id='page.aspx?uid=123'"); System.out.println(m.groupCount() > 0 ? m.group(1) : "No Matches"); } }

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  • Juju instances in aganet-state: down after turning them off (and back on) on EC2

    - by Tyler McAdams
    I turned my Juju instances off on EC2 for a while and after bringing them back online they seem to be in an odd state: [code] claude-vm@claude-vm-fusion:~/Documents/Shell Scripts$ juju status 2012-11-17 17:06:44,094 INFO Connecting to environment... 2012-11-17 17:06:45,590 INFO Connected to environment. machines: 0: agent-state: not-started dns-name: ec2-54-242-142-196.compute-1.amazonaws.com instance-id: i-b0996fcf instance-state: running 1: agent-state: down dns-name: ec2-50-19-186-245.compute-1.amazonaws.com instance-id: i-8c8375f3 instance-state: running 2: agent-state: down dns-name: ec2-54-242-255-238.compute-1.amazonaws.com instance-id: i-56807629 instance-state: running services: wordpress: charm: cs:precise/wordpress-9 exposed: true relations: db: - wordpress-db loadbalancer: - wordpress units: wordpress/0: agent-state: down machine: 2 open-ports: - 80/tcp public-address: ec2-54-242-227-57.compute-1.amazonaws.com wordpress-db: charm: cs:precise/mysql-10 relations: db: - wordpress units: wordpress-db/0: agent-state: down machine: 1 public-address: ec2-54-242-212-177.compute-1.amazonaws.com 2012-11-17 17:06:47,274 INFO 'status' command finished successfully [/code] Can I not take my instances down for a while? Or is this something else?

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  • Problem with pattern matching in ocaml

    - by Antony
    I wrote the function used to decompose a Boolean function, the problem is that the compilation I get this : "Warning 5: this function application is partial, maybe some arguments are missing." How can I solve this problem? I've set wrong the patter matching or I can not run this operation with pattern matching The code is the following: let rec decomposition state_init state prec formula = match formula with And form -> (fun () -> let f1 = List.hd form in let f2 = And(List.tl form )in let new_state = Forms (state_init,f1) in decomposition state_init new_state state f1; decomposition state_init new_state state f2; Hashtbl.add graph new_state (("",false,state :: []) , []) ; let x = Hashtbl.find graph state in let succ = state :: snd x in let (desc,last,ptrs) = fst x in Hashtbl.replace graph state ( ("And-node",last,ptrs) , succ))

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  • How do I reuse a state machine in a slightly different way?

    - by JoJo
    Problem I have a big state machine. The design requirements of the project have changed such that I need to re-use this state machine in another place. All the states remain the same in this new place, but a few states run slightly different stuff. What design pattern allows me to reuse this state machine? Motivation I am building a video player. It is modeled by a state machine with these states: stopped, loading, playing, paused, crashed, and some more... This video player needs to be used on two web pages. When the player crashes on the first page, it should show an error message below. If the player crashes on the second page, the error message should appear in the center of the video and pulsate a few times.

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  • Extract registry key from NTBackup System State backup

    - by phoenix8
    A Windows Server 2003 machine died recently but I need some information that was contained in the now-defunct server's registry. I have a "System State" backup file created by the Windows Server 2003 built-in backup program (NTBackup.exe). Is there any way to extract a key/value out of the backup file? I might be able do a Win2003 install on a similar machine then do a system-state restore but that's a lot of effort and I don't know for certain that the system-state restore will work on a different spec machine. (Would it work if I booted up in 'safe mode'?) But I'd really rather just get at the data straight out of the NTBackup file zip-file-esque styles if that's possible.

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