Search Results

Search found 26869 results on 1075 pages for 'library design'.

Page 156/1075 | < Previous Page | 152 153 154 155 156 157 158 159 160 161 162 163  | Next Page >

  • null values vs "empty" singleton for optional fields

    - by Uko
    First of all I'm developing a parser for an XML-based format for 3D graphics called XGL. But this question can be applied to any situation when you have fields in your class that are optional i.e. the value of this field can be missing. As I was taking a Scala course on coursera there was an interesting pattern when you create an abstract class with all the methods you need and then create a normal fully functional subclass and an "empty" singleton subclass that always returns false for isEmpty method and throws exceptions for the other ones. So my question is: is it better to just assign null if the optional field's value is missing or make a hierarchy described above and assign it an empty singleton implementation?

    Read the article

  • Are there any examples of a temporal field/object updater?

    - by Bryan Agee
    The system in question has numerous examples of temporal objects and fields--ones which are a certain variable at a certain point in time. An example of this would be someone's rate of pay--there are different answers depending on when you ask and what the constraints might be; eg, can there ever be more than one of a certain temporal object concurrently, etc. Ideally, there would be an object that handles those constraints when a new state/stateful object is introduced; when a new value is set, it would prevent creating negative ranges and overlaps. Martin Fowler has written some great material on this (such as this description of Temporal Objects) , but what I've found of it tends to be entirely theoretic, with no concrete implementations. PHP is the target language, but examples in any language would be most helpful.

    Read the article

  • Are there specific legal issues for web developers working on sex dating sites?

    - by YumYumYum
    Say I have created many ordinary websites which are not related to any dating/sexual content. Are the rules and regulations for a developer the same when making a sex-related dating site? I'm talking about a site where people meet together and get to know each other, with the intent of having a sexual relationship (you know what I mean), also featuring webcam sex, but not explicitly a porno site. Do such sites have any special legal issues for developers compared with non-sexual/dating sites?

    Read the article

  • Which Game Engine to Use for an Angry Bird style game? [JAVA] [on hold]

    - by Arch1tect
    Our team is building an Angry Bird Style game, and we have only about ten days. The game is a little more complex than Angry Bird because there are two players, they each have a castle with pigs to protect(not destroy:)). And the goal is to destroy the other player's pigs. I wonder what Game Engine would help us finish this game most efficiently. We at least need a physics engine but I guess game engine is more helpful since it usually includes physics engine. Correct me if I'm wrong. (So I'm wondering which game engine I should use, if it's just physics engine, I'll use box2d) Networking may or may not be added later depend on time we have. Thanks in advance for any advice! EDIT: image looks small, I'll add one:

    Read the article

  • Is it possible to calculate or mathematically prove if a game is balanced / fair?

    - by Lurca
    This question is not focussed on video games but games in general. I went to a boardgame trade fair yesterday and asked myself if there is a way to calculate the fairness of a game. Sure, some of them require a good portion of luck, but it might be possible to calculate if some character is overpowered. Especially in role-playing games and trading card games. How, for example, can the creators of "Magic: The Gathering" make sure that there isn't the "one card that beats them all", given the impressive number of available cards?

    Read the article

  • What are examples of games with "minimalist" models/art assets

    - by Ken
    When teaching game development, my student's obsess about building realistic or complex art/models/animation. And spending wayyy to much time trying to get accurate collision detection between two 3D models [despite my best efforts] However I would like them to spend more time thinking about developing the game mechanics, interaction and game play. I'm looking for some games where the visuals are simple but have good game play. Things I am thinking about are Cubes' vs Spheres or Impossible Game. What are more examples of visually simple (preferably 3D) games to help inspire my students?

    Read the article

  • Is ORM an Anti-Pattern?

    - by derphil
    I had a very stimulating and interessting discussion with a colleague about ORM and it's Pros and Cons. In my opinion, an ORM is useful only in the rarest cases. At least in my experience. But I don't want to list my own arguments at this time. So I ask you, what do you think about ORM? What are the Pros and the Cons? P.S. I've posted this "question" yesterday on Stackoverflow, but some of the user think, that this should better posted here.

    Read the article

  • Is Paypal the best solution for payment gateway for a website?

    - by Pennf0lio
    I have a realty website that needs a payment gateway for their property reservation. The reservation fee range from $500-$600 and about 5-6 people per month. I was wondering if Paypal is the best solution for accepting Payment. What will be the Pros and Cons using Paypal. Paypal was my first choice because It's easy to integrate on my existing website and I wouldn't be minding so much on the security. P.S. It's not a part of the question, But If you can site some realty website that accept payment and would be a good inspiration. It would be highly appreciated. Thanks!

    Read the article

  • Method for spawning enemies according to player score and game time

    - by Sun
    I'm making a top-down shooter and want to scale the difficulty of the game according to what the score is and how much time has Passed. Along with this, I want to spawn enemies in different patterns and increase the intervals at which these enemies are shown. I'm going for a similar effect to Geometry wars. However, I can think of a to do this other than have multiple if-else statments, e.g. : if (score > 1000) { //spawn x amount if enemies } else if (score > 10000) { //spawn x amount of enemy type 1 & 2 } else if (score > 15000) { //spawn x amount of enemy type 1 & 2 & 3 } else if (score > 25000) { //spawn x amount of enemy type 1 & 2 & 3 //create patterns with enemies } ...etc What would be a better method of spawning enemies as I have described?

    Read the article

  • Relationships in a Chen ERD

    - by Nibroc A Rehpotsirhc
    I am working on a Chen ERD to model our organizations merchandise. Our central entity is a Style. We have supplemental entities of Color and Season. I am defining our assortment as the relationship between these three entities, and this relationship itself will have attributes and is defined by the three entities which participate in the mandatory relationship. The rules are; Many Styles can be offered in a Season, and a Style can be offered in many Seasons. Within a Season, a Style can be offered in Many Colors. I then have 2 other entities, one of which I believe is a weak entity, Climate, and the other may be weak, but I am not sure, this being Transaction Channel. I am thinking of these as relationships off of a relationship? Meaning, for a given Style/Color combination offered in a Season, it can be available through 1 or more Transaction Channels. Additionally, within a season, a given Style/Color combination can be intended for 1 or more Climates. Is it valid to have relationships off of relationships? Or does this requirement dictate that I should think of this Style/Color/Season relationship as an entity itself, and define the relationships to Climate and Transaction Channel off of this entity?

    Read the article

  • Can someone recommend an appriopriate drawing tablet that fits my needs?

    - by Syg
    I'm looking for something that can help me to easily create small hand drawn graphics and mock-ups digitalize technical drawings I would normally draw on a whiteboard. I'm a developer, not a designer, so it doesn't have to be high-end I guess. Just something to help make it easier, more fun and more productive to quickly draw mockups etc. After a quick search I landed on the wacom site, but it's hard for me to tell the difference between the offerings never having used something like this. Is small too small? is it annoying? Other suggestion are also welcome ofcourse. Thanx for any help you can give me

    Read the article

  • Best practices for using namespaces in C++.

    - by Dima
    I have read Uncle Bob's Clean Code a few months ago, and it has had a profound impact on the way I write code. Even if it seemed like he was repeating things that every programmer should know, putting them all together and putting them into practice does result in much cleaner code. In particular, I found breaking up large functions into many tiny functions, and breaking up large classes into many tiny classes to be incredibly useful. Now for the question. The book's examples are all in Java, while I have been working in C++ for the past several years. How would the ideas in Clean Code extend to the use of namespaces, which do not exist in Java? (Yes, I know about the Java packages, but it is not really the same.) Does it make sense to apply the idea of creating many tiny entities, each with a clearly define responsibility, to namespaces? Should a small group of related classes always be wrapped in a namespace? Is this the way to manage the complexity of having lots of tiny classes, or would the cost of managing lots of namespaces be prohibitive?

    Read the article

  • MiniMax not working properly(for checkers game)

    - by engineer
    I am creating a checkers game but My miniMax is not functioning properly,it is always switching between two positions for its move(index 20 and 17).Here is my code: public double MiniMax(int[] board, int depth, int turn, int red_best, int black_best) { int source; int dest; double MAX_SCORE=-INFINITY,newScore; int MAX_DEPTH=3; int[] newBoard=new int[32]; generateMoves(board,turn); System.arraycopy(board, 0, newBoard, 0, 32); if(depth==MAX_DEPTH) { return Evaluation(turn,board);} for(int z=0;z<possibleMoves.size();z+=2){ source=Integer.parseInt(possibleMoves.elementAt(z).toString()); System.out.println("SOURCE= "+source); dest=Integer.parseInt(possibleMoves.elementAt(z+1).toString());//(int[])possibleMoves.elementAt(z+1); System.out.println("DEST = "+dest); applyMove(newBoard,source,dest); newScore=MiniMax(newBoard,depth+1,opponent(turn),red_best, black_best); if(newScore>MAX_SCORE) {MAX_SCORE=newScore;maxSource=source; maxDest=dest;}//maxSource and maxDest will be used to perform the move. if (MAX_SCORE > black_best) { if (MAX_SCORE >= red_best) break; /* alpha_beta cutoff */ else black_best = (int) MAX_SCORE; //the_score } if (MAX_SCORE < red_best) { if (MAX_SCORE<= black_best) break; /* alpha_beta cutoff */ else red_best = (int) MAX_SCORE; //the_score } }//for ends return MAX_SCORE; } //end minimax I am unable to find out the logical mistake. Any idea what's going wrong?

    Read the article

  • How do I start correctly in building database classes in c#?

    - by e4rthdog
    I am new in C# programming and in OOP. I need to dive into web applications for my company, and I need to do it fast and correct. So even that I know ASP.NET MVC is the way to go, I want to start with some simple applications with ASP.NET Webforms and then advance to MVC logic. Also regarding my db classes: I plan to create common database classes in order to be able to use them either from WinForms or ASP.NET applications. I also know that the way to go is to learn about ORM and EF. BUT I also want to start from where I am feeling comfortable and that is the traditional ADO.NET way. So about my Data Access Layer classes: Should I return my results in datasets or arraylists/lists? Should my methods do their own connect/disconnect from the db, or have separate methods and let the application maintain the connection?

    Read the article

  • Avoiding the Anaemic Domain - How to decide what single responsibility a class has

    - by thecapsaicinkid
    Even after reading a bunch I'm still falling into the same trap. I have a class, usually an enity. I need to implement more than one, similar operations on this type. It feels wrong to (seemingly arbitrarily) choose one of these operations to belong inside the entity and push the others out to a separate class; I end up pushing all operations to service classes and am left with an anaemic domain. As a crude example, imagine the typical Employee class with numeric properties to hold how many paid days the employee is entitled to for both sickness and holiday and a collection of days taken for each. public class Employee { public int PaidHolidayAllowance { get; set; } public int PaidSicknessAllowance { get; set; } public IEnumerable<Holiday> Holidays { get; set; } public IEnumerable<SickDays> SickDays { get; set; } } I want two operations, one to calculate remaining holiday, another for remaining paid sick days. It seems strange to include say, CalculateRemaingHoliday() in the Employee class and bump CalculateRemainingPaidSick() to some PaidSicknessCalculator class. I would end up with a PaidSicknessCalculator and a RemainingHolidayCalculator and the anaemic Employee entity as seen above. The other alternative would be to put both operations in the Employee class and kick Single Responsibility to the curb. That doesn't make for particularly maintainable code. I suppose the Employee class should have some initialisation/validation logic (not accepting negative alowances etc.) So maybe I just stick to basic initialisation and validation in the entities themselves and be happy with my separate calculator classes. Or maybe I should be asking myself if Anaemic Domain is actually causing me some tangible problems with my code.

    Read the article

  • Implementing the transport layer for a SIP UAC

    - by Jonathan Henson
    I have a somewhat simple, but specific, question about implementing the transport layer for a SIP UAC. Do I expect the response to a request on the same socket that I sent the request on, or do I let the UDP or TCP listener pick up the response and then route it to the correct transaction from there? The RFC does not seem to say anything on the matter. It seems that especially using UDP, which is connection-less, that I should just let the listeners pick up the response, but that seems sort of counter intuitive. Particularly, I have seen plenty of UAC implementations which do not depend on having a Listener in the transport layer. Also, most implementations I have looked at do not have the UAS receiving loop responding on the socket at all. This would tend to indicate that the client should not be expecting a reply on the socket that it sent the request on. For clarification: Suppose my transport layer consists of the following elements: TCPClient (Sends Requests for a UAC via TCP) UDPClient (Sends Requests for a UAC vid UDP) TCPSever (Loop receiving Requests and dispatching to transaction layer via TCP) UDPServer (Loop receiving Requests and dispatching to transaction layer via UDP) Obviously, the *Client sends my Requests. The question is, what receives the Response? The *Client waiting on a recv or recvfrom call on the socket it used to send the request, or the *Server? Conversely, the *Server receives my requests, What sends the Response? The *Client? doesn't this break the roles of each member a bit?

    Read the article

  • What is the relationship between the business logic layer and the data access layer?

    - by Matt Fenwick
    I'm working on an MVC-ish app (I'm not very experienced with MVC, hence the "-ish"). My model and data access layer are hard to test because they're very tightly coupled, so I'm trying to uncouple them. What is the nature of the relationship between them? Should just the model know about the DAL? Should just the DAL know about the model? Or should both the model and the DAL be listeners of the other? In my specific case, it's: a web application the model is client-side (javascript) the data is accessed from the back-end using Ajax persistence/back-end is currently PHP/MySQL, but may have to switch to Python/GoogleDataStore on the GAE

    Read the article

  • How can I selectively update XNA GameComponents?

    - by Bill
    I have a small 2D game I'm working on in XNA. So far, I have a player-controlled ship that operates on vector thrust and is terribly fun to spin around in circles. I've implemented this as a DrawableGameComponent and registered it with the game using game.Components.Add(this) in the Ship object constructor. How can I implement features like pausing and a menu system with my current implementation? Is it possible to set certain GameComponents to not update? Is this something for which I should even be using a DrawableGameComponent? If not, what are more appropriate uses for this?

    Read the article

  • When do domain concepts become application constructs?

    - by Noren
    I recently posted a question regarding recovering a DDD architecture that became an anemic domain model into a multitier architecture and this question is a follow-on of sorts. My question is when do domain concepts become application constructs. My application is a local client C# 4/WPF with the following architecture: Presentation Layer Views ViewModels Business Layer ??? Domain Layer Classes that take the POCOs with primitive types and create domain concepts (e.g. image, layer, etc) Sanity checks values (e.g. image width 0) Interfaces for DTOs Interface for a repository that abstracts the filesystem Data Access Layer Classes that parse the proprietary binary files into POCOs with primitive types by explicit knowledge of the file format Implementation of domain DTOs Implementation of domain repository class Local Filesystem Proprietary binary files When does the MyImageType domain class with Int32 width, height, and Int32[] pixels become a System.Windows.Media.ImageDrawing? If I put it in the domain layer, it seems like implemenation details are being leaked (what if I didn't want to use WPF?). If I put it in the presentation layer, it seems like it's doing too much. If I create a business layer, it seems like it would be doing too little since there are few "rules" given the CRUD nature of the application. I think all of my reading has lead to analysis paralysis, so I thought fresh eyes might lend some perspective.

    Read the article

  • Help in (re)designing my Swing application

    - by Harihar Das
    I have developed a Swing application that controls execution of several script like jobs. I need to display the interim output of the jobs concurrently. I have followed MVC while writing the application. The application is working as expected. But off late I have the following requirements in hand: A few of the script jobs need special user privileges to execute so as to access specialized resources. There seems to be now way in Java to impersonate as a different user while running an application.[examined in this question]. Also trying to run the Swing application as a scheduled task in windows is not helping. Once started the jobs should be running even if the user logs off after starting the jobs. I am thinking of separating the execution logic from the UI and run that as a service; and introduce JMS in between the two layers so as to store/retrieve the interim the output. Note: I need to run this application on windows Any ideas on meeting my requirements will be highly appreciated.

    Read the article

  • How to keep balance / Unlock items / achievement rules

    - by Mark Knol
    I'm working on an engine for a game, too learn javascript and just because its fun. I'm a flashdeveloper, I know how to build websites. Now making games is a different challenge, javascript is a challenge, but I'd love to learn how to structure code and what patterns are common. I dont mind if the game ever finish, I'm mostly interested in the programming part of it. I dont have a particular endresult in mind, so I'll see where it takes me. I currently have a system where you can buy items. The items cost a specified amount of gold, silver, diamonds etc. When you have selected and bought the item, it takes time before getting rewarded. When time is over, you are getting rewarded with other properties (gold, energy, diamonds). For example, you can buy an apple for 50gold, It takes a minute, you get rewarded with 75energy. Or if you take a run, it cost 50energy, it takes 5minutes, reward is 25gold and 25silver. These definitions is what i call actions. Currently I already have a system where this already works and I can define as much actions with as much properties as I want. The definitions I have kinda looks like this: {id:101, category:544, onInit:{gold:-75}, onComplete:{energy:75}, time:2000, name:"Apple", locked: false} {id:102, category:544, onInit:{gold:-135}, onComplete:{energy:145}, time:2000, name:"Banana", locked: false} {id:106, category:302, onInit:{energy:-50, power: -25}, onComplete:{gold:100, diamonds:2}, time:10000, name:"Run", locked: false} {id:107, category:302, onInit:{energy:-70, silver: -55}, onComplete:{gold:100}, time:10000, name:"Dance", locked: false} {id:108, category:302, onInit:{energy:-230, power: -355}, onComplete:{gold:70, silver:70}, time:10000, name:"Fitness", locked: false} Now, I would love to add a system where I can lock/unlock the actions using achievement rules. Lets say, if you buy 10 apples, you unlock a new action, like bananas which cost more, and reward more. In the future I maybe want to restrict achievements and actions to levels. I am kinda stuck how to structure this. I have 2 questions: Which patterns are used to define achievements? How/where are they defined? Should it be part of the action, or should it be a separate controller? Is it a good idea to register all completed actions to it? I think I want multiple types of achievement rules, Id love to hear some ideas how to develop it. How do you create/find a good balance, so the user does not get stuck or can cheat by repeat a pattern of actions to get too much rewards. I know there is not a simple answer and i'm lacking of a good game-concept, but I wonder if anyone created such a game and how you dealed and played with it.

    Read the article

  • Improving Click and Drag with C++

    - by Josh
    I'm currently using SFML 2.0 to develop a game in C++. I have a game sprite class that has a click and drag method. The method works, but there is a slight problem. If the mouse moves too fast, the object the user selected can't keep up and is left behind in the spot where the mouse left its bounds. I will share the class definition and the given function implementation. Definition: class codePeg { protected: FloatRect bounds; CircleShape circle; int xPos, yPos, xDiff, yDiff, once; int xBase, yBase; Vector2i mousePos; Vector2f circlePos; public: void init(RenderWindow& Window); void draw(RenderWindow& Window); void drag(RenderWindow& Window); void setPegPosition(int x, int y); void setPegColor(Color pegColor); void mouseOver(RenderWindow& Window); friend int isPegSelected(void); }; Implementation of the "drag" function: void codePeg::drag(RenderWindow& Window) { mousePos = Mouse::getPosition(Window); circlePos = circle.getPosition(); if(Mouse::isButtonPressed(Mouse::Left)) { if(mousePos.x > xPos && mousePos.y > yPos && mousePos.x - bounds.width < xPos && mousePos.y - bounds.height < yPos) { if(once) { xDiff = mousePos.x - circlePos.x; yDiff = mousePos.y - circlePos.y; once = 0; } xPos = mousePos.x - xDiff; yPos = mousePos.y - yDiff; circle.setPosition(xPos, yPos); } } else { once = 1; xPos = xBase; yPos = yBase; xDiff = 0; yDiff = 0; circle.setPosition(xBase, yBase); } Window.draw(circle); } Like I said, the function works, but to me, the code is very ugly and I think it could be improved and could be more efficient. The only thing I can think of as to why the object cannot keep up with the mouse is that there are too many function calls and/or checks. The user does not really have to mouse the mouse "fast" for it to happen, I would say at an average pace the object is left behind. How can I improve the code so that the object remains with the mouse when it is selected? Any help improving this code or giving advice is greatly appreciated.

    Read the article

  • How to approach big developer companies if I have a killer game idea? (for mobile devices)

    - by Balázs Dávid
    I have an idea for a game that has a potential, but I'm not a programmer. How to tell this to development companies without being my idea stolen? All I want from the company is first to watch a 3-minute long video presentation about my idea and if they see fantasy in it then we can talk about the details. I have already sent an e-mail to several big companies that have the expertise needed to code the game, they haven't answer me. Actually the idea is nothing fancy, no 3D, but fun and unique.

    Read the article

  • What is required for a scope in an injection framework?

    - by johncarl
    Working with libraries like Seam, Guice and Spring I have become accustomed to dealing with variables within a scope. These libraries give you a handful of scopes and allow you to define your own. This is a very handy pattern for dealing with variable lifecycles and dependency injection. I have been trying to identify where scoping is the proper solution, or where another solution is more appropriate (context variable, singleton, etc). I have found that if the scope lifecycle is not well defined it is very difficult and often failure prone to manage injections in this way. I have searched on this topic but have found little discussion on the pattern. Is there some good articles discussing where to use scoping and what are required/suggested prerequisites for scoping? I interested in both reference discussion or your view on what is required or suggested for a proper scope implementation. Keep in mind that I am referring to scoping as a general idea, this includes things like globally scoped singletons, request or session scoped web variable, conversation scopes, and others. Edit: Some simple background on custom scopes: Google Guice custom scope Some definitions relevant to above: “scoping” - A set of requirements that define what objects get injected at what time. A simple example of this is Thread scope, based on a ThreadLocal. This scope would inject a variable based on what thread instantiated the class. Here's an example of this: “context variable” - A repository passed from one object to another holding relevant variables. Much like scoping this is a more brute force way of accessing variables based on the calling code. Example: methodOne(Context context){ methodTwo(context); } methodTwo(Context context){ ... //same context as method one, if called from method one } “globally scoped singleton” - Following the singleton pattern, there is one object per application instance. This applies to scopes because there is a basic lifecycle to this object: there is only one of these objects instantiated. Here's an example of a JSR330 Singleton scoped object: @Singleton public void SingletonExample{ ... } usage: public class One { @Inject SingeltonExample example1; } public class Two { @Inject SingeltonExample example2; } After instantiation: one.example1 == two.example2 //true;

    Read the article

< Previous Page | 152 153 154 155 156 157 158 159 160 161 162 163  | Next Page >