Search Results

Search found 39440 results on 1578 pages for 'possible homework'.

Page 388/1578 | < Previous Page | 384 385 386 387 388 389 390 391 392 393 394 395  | Next Page >

• Get More From Your Service Request

  - by Get Proactive Customer Adoption Team

  Leveraging Service Request Best Practices Use best practices to get there faster. In the daily conversations I have with customers, they sometimes express frustration over their Service Requests. They often feel powerless to make needed changes, so their sense of frustration grows. To help you avoid some of the frustration you might feel in dealing with your Service Requests (SR), here are a few pointers that come from our best practice discussions. Be proactive. If you can anticipate some of the questions that Support will ask, or the information they may need, try to provide this up front, when you log the SR. This could be output from the Remote Diagnostic Agent (RDA), if this is a database issue, or the output from another diagnostic tool, if you’re an EBS customer. Any information you can supply that helps us understand the situation better, helps us resolve the issue sooner. As you use some of these tools proactively, you might even find the solution to the problem before you log an SR! Be right. Make sure you have the correct severity level. Since you select the initial severity level, it’s easy to accept the default without considering how significant this may be. Business impact is the driving factor, so make sure you take a moment to select the severity level that is appropriate to the situation. Also, make sure you ask us to change the severity level, should the situation dictate. Be responsive! If this is an important issue to you, quickly follow up on any action plan submitted to you by Oracle Support. The support engineer assigned to your Service Request will be able to move the issue forward more aggressively when they have the needed information. This is crucial in resolving your issues in a timely manner. Be thorough. If there are five questions in the action plan, make sure you provide an answer for all five questions in one response, rather than trickling them in one at a time. This will allow the engineer to look at all of the information as a whole and to avoid multiple trips to your SR, saving valuable time and getting you a resolution sooner. Be your own advocate! You know your situation best; make sure Oracle Support understands both how and why this issue is important to you and your company. Use the escalation process if you're concerned that your SR isn't going the right direction, the right pace, or through the right person. Don't wait until you're frustrated and angry. An escalation is as simple as a quick conversation on the phone and can be amazingly effective in getting your issues back on track. The support manager you speak with is empowered to make any needed changes. Be our partner. You can make your support experience better. When your SR has been resolved, you may receive a survey request. This is intended to get your feedback about how your SR went and what we can do to improve your overall support experience. Oracle Support is here to help you. Our goal with any Service Request is to provide the best possible solution as quickly as possible. With your help, we’ll be able to do this with your Service Request too.  

  Read the article

• Software Center seems to freeze system when installing, syslog has "blocked for more than 120 seconds" errors

  - by nbm

  12.04 (precise) 64-bit Kernel Linux 3.2.0-39 3.6GB memory Intel Core 2 Duo CPU @ 2.40GHz x2 WUBI-installed Ubuntu running on a MacBook Pro 7.1 with OSX running Vista via Boot Camp (hey, I like lots of OS's m'kay?) When installing from Ubuntu software center my system very frequently freezes. This has happened 4 of the last 5 installs. Most recently I was installing the Google Earth .deb from Google's website: clicking the .deb file automatically opens Software Center (otherwise I would have used Synaptic, as I've grown to expect Software Center to freeze my system and I'm rather tired of it.) By "freeze" I mean nothing works: no dash, no launcher, no mouse movement, no alt-tab, can't open terminal (keyboard does not work). Software center does show the "installing" icon but after that it greys out and I can't click anything. REISUB has no effect but a cold power-down and restart is possible. Occasionally, after 5-10 minutes, I'll be able to move the mouse / use the keyboard and run a launcher command or two, although other open apps (Chrome and Software Center) will still be greyed-out/frozen. (I've never waited longer than that - if still unresponsive after 15 minutes I just power down and restart.) Most recently, which is why I am finally posting a question, I waited about 15 minutes and was finally able to open System Monitor while this was going on. Processes tells me that System Monitor is using about 20% of CPU, and nothing else is using much (zeros mostly). In fact I didn't even see Software Center listed? However at this point the system finally partially unfroze, the installation completed, and while I wasn't about to close Software Center I was able to do a system shutdown and fresh restart and I went and took a look at the syslog. In /var/log/syslog I see a lot of ":blocked for more than 120 seconds" messages. Similar to ubuntu hang out with this message :blocked for more than 120 seconds Which has not been answered, and I'm not running a virtual machine. My full syslog with stack traces looks very, very similar to this: Why do tasks on Amazon Xen instance block for over 120 seconds causing server to hang? Note that that question was solved, but that's because the problem was being caused by Amazon and Amazon fixed the bug. I'm not running anything Amazon-related. My syslog does look very similar, however. My question is also similar to this: Troubleshooting server hang But the referenced "duplicate" in that question is about how to kill processes/restart when the system freezes. I know how to kill processes and restart. I want to figure out what is causing the problem so I can try to fix it. I realize that I could just use Synaptic instead of Ubuntu Software Center, but I'd like to try to solve the problem if possible. I'm thinking I should perhaps submit a bug report, but I wanted to first see if anyone else was having any similar problems, and if so what you all did to fix it. I see a number of questions about Software Center freezing and others, including those I linked, about the "blocked for more than 120 seconds" log error, but I didn't see any question that links the two. I did save a copy of the syslog report if anyone wants to see it, but as mentioned it's quite similar to the one posted in the Amazon-related question...and I didn't want to take up even more space unnecessarily as, my apologies - this question has already become extremely verbose!

  Read the article

• How to place rooms proceduraly (rule based) on in a game word

  - by gardian06

  I am trying to design the algorithm for my level generation which is a rule driven system. I have created all the rules for the system. I have taken care to insure that all rooms make sense in a grid type setup. for example: these rooms could make this configuration The logic flow code that I have so far Door{ Vector3 position; POD orient; // 5 possible values (up is not an option) bool Open; } Room{ String roomRule; Vector3 roomPos; Vector3 dimensions; POD roomOrient; // 4 possible values List doors<Door>; } LevelManager{ float scale = 18f; List usedRooms<Room>; List openDoors<Door> bool Grid[][][]; Room CreateRoom(String rule, Vector3 position, POD Orient){ place recieved values based on rule fill in other data } Vector3 getDimenstions(String rule){ return dimensions of the room } RotateRoom(POD rotateAmount){ rotate all items in the room } MoveRoom(Room toBeMoved, POD orientataion, float distance){ move the position of the room based on inputs } GenerateMap(Vector3 size, Vector3 start, Vector3 end){ Grid = array[size.y][size.x][size.z]; Room floatingRoom; floatingRoom = Room.CreateRoom(S01, start, rand(4)); usedRooms.Add(floatingRoom); for each Door in floatingRoom.doors{ openDoors.Add(door); } // fill used grid spaces floatingRoom = Room.CreateRoom(S02, end, rand(4); usedRooms.Add(floatingRoom); for each Door in floatingRoom.doors{ openDoors.Add(door); } Vector3 nRoomLocation; Door workingDoor; string workingRoom; // fill used grid spaces // pick random door on the openDoors list workingDoor = /*randomDoor*/ // get a random rule nRoomLocation = workingDoor.position; // then I'm lost } } I know that I have to make sure for convergence (namely the end is reachable), and to do this until there are no more doors on the openDoors list. right now I am simply trying to get this to work in 2D (there are rules that introduce 3D), but I am working on a presumption that a rigorous algorithm can be trivially extended to 3D. EDIT: my thought pattern so far is to take an existing open door and then pick a random room (restrictions can be put in later) place that room's center at the doors location move the room in the direction of the doors orientation half the rooms dimension w/respect to that axis then test against the 3D array to see if all the grid points are open, or have been used, or if there is even space to put the room (caseEdge) if caseEdge (which can also occur in between rooms) then put the door on a toBeClosed list, and remove it from the open list (placing a wall or something there). then to do some kind of test that both the start, and the goal are connected, and reachable from each other (each room has nodes for AI, but I don't want to "have" to pull those out to accomplish this). but this logic has the problem for say the U, or L shaped rooms in my example, and then I also have a problem conceptually if the room needs to be rotated.

  Read the article

• Come up with a real-world problem in which only the best solution will do (a problem from Introduction to algorithms) [closed]

  - by Mike

  EDITED (I realized that the question certainly needs a context) The problem 1.1-5 in the book of Thomas Cormen et al Introduction to algorithms is: "Come up with a real-world problem in which only the best solution will do. Then come up with one in which a solution that is “approximately” the best is good enough." I'm interested in its first statement. And (from my understanding) it is asked to name a real-world problem where only the exact solution will work as opposed to a real-world problem where good-enough solution will be ok. So what is the difference between the exact and good enough solution. Consider some physics problem for example the simulation of the fulid flow in the permeable medium. To make this simulation happen some simplyfing assumptions have to be made when deriving a mathematical model. Otherwise the model becomes at least complex and unsolvable. Virtually any particle in the universe has its influence on the fluid flow. But not all particles are equal. Those that form the permeable medium are much more influental than the ones located light years away. Then when the mathematical model needs to be solved an exact solution can rarely be found unless the mathematical model is simple enough (wich probably means the model isn't close to reality). We take an approximate numerical method and after hours of coding and days of verification come up with the program or algorithm which is a solution. And if the model and an algorithm give results close to a real problem by some degree that is good enough soultion. Its worth noting the difference between exact solution algorithm and exact computation result. When considering real-world problems and real-world computation machines I believe all physical problems solutions where any calculations are taken can not be exact because universal physical constants are represented approximately in the computer. Any numbers are represented with the limited precision, at least limited by amount of memory available to computing machine. I can imagine plenty of problems where good-enough, good to some degree solution will work, like train scheduling, automated trading, satellite orbit calculation, health care expert systems. In that cases exact solutions can't be derived due to constraints on computation time, limitations in computer memory or due to the nature of problems. I googled this question and like what this guy suggests: there're kinds of mathematical problems that need exact solutions (little note here: because the question is taken from the book "Introduction to algorithms" the term "solution" means an algorithm or a program, which in this case gives exact answer on each input). But that's probably more of theoretical interest. So I would like to narrow down the question to: What are the real-world practical problems where only the best (exact) solution algorithm or program will do (but not the good-enough solution)? There are problems like breaking of cryptographic ciphers where only exact solution matters in practice and again in practice the process of deciphering without knowing a secret should take reasonable amount of time. Returning to the original question this is the problem where good-enough (fast-enough) solution will do there's no practical need in instant crack though it's desired. So the quality of "best" can be understood in any sense: exact, fastest, requiring least memory, having minimal possible network traffic etc. And still I want this question to be theoretical if possible. In a sense that there may be example of computer X that has limited resource R of amount Y where the best solution to problem P is the one that takes not more than available Y for inputs of size N*Y. But that's the problem of finding solution for P on computer X which is... well, good enough. My final thought that we live in a world where it is required from programming solutions to practical purposes to be good enough. In rare cases really very very good but still not the best ones. Isn't it? :) If it's not can you provide an example? Or can you name any such unsolved problem of practical interest?

  Read the article

• Building Enterprise Smartphone App &ndash; Part 1: Why Build Smart Phone Apps

  - by Tim Murphy

  This is part 1 in a series of post based on a talk I gave recently at the Chicago Information Technology Architects Group.  Feel free to leave feedback. Intro Most of us already carry smartphones. We play games on them. We keep up with what is going on with our friends and our favorite teams. We take pictures of our kids at their events. But the question is if that is all they are good for. Many companies have aspects of their business that lend themselves to being performed by mobile devices. Some of them lean toward larger device such as tablets, but many can be executed on smartphones. This and the following articles will discuss some of the possible applications of smartphone technology for businesses, the platforms that are available and the considerations you need to make when building them. I'll take a look at some specific scenarios and wrap up with a couple of capabilities that are just emerging that can be used in the future. Why Build Enterprise Smartphone Applications So what are some of the ways that you can leverage smartphone technology to gain efficiency in your business or a clients business. There are a few major areas that I have seen mobile platforms being an advantage to. Your mobile sales force is a key candidate for leveraging smartphone apps.  They can visit clients in their retail location and place orders on site. It is a more personal approach which can gain you customer loyalty.  A sales person may also gather information about the way a client does business or who their target market is. This allows them you to focus marketing information or build customized support for your customer. You may also have need to track physical inventory in a store. This is something that has historically been done with laser scanners, but with the camera capabilities in today's phones and tablets it is possible to use more general multi-purpose devices.  This can save costs on both hardware and telecommunication contracts. Delivery verification is another area that historically has been the domain of specialized devices but can now be accomplished with smartphones.  This also reduces costs because it is also used for communicating with the driver and other operations.  Add to that the navigation capability of smartphones and you can see how the return on investment increases. Executives are always on the go. They spend most of their time in meetings and yet they need access to decision making information at their finger tips. With a smartphone app they can get alerts when major sales are closed or critical accounting process are completed that may need their attention. They can also answer questions by instantly pulling up BI reports. I have often heard operations support people say that they need things like VPN and RDP from their phones. If they can also have notifications of outages or critical support requests they can be react to situations without needing to be tied to their desks. These are all valid reasons to need smartphone applications.  In the next installment I will discuss platforms and features. del.icio.us Tags: Smartphones,Enterprise Smartphone Apps,Architecture

  Read the article

• Rethinking Oracle Optimizer Statistics for P6 Part 2

  - by Brian Diehl

  In the previous post (Part 1), I tried to draw some key insights about the relationship between P6 and Oracle Optimizer Statistics.  The first is that average cardinality has the greatest impact on query optimization and that the particular queries generated by P6 are more likely to use this average during calculations. The second is that these are statistics that are unlikely to change greatly over the life of the application. Ultimately, our goal is to get the best query optimization possible.  Or is it? Stability No application administrator wants to get the call at 9am that their application users cannot get there work done because everything is running slow. This is a possibility with a regularly scheduled nightly collection of statistics. It may not just be slow performance, but a complete loss of service because one or more queries are optimized poorly. Ideally, this should not be the case. The database optimizer should make better decisions with more up-to-date data. Better statistics may give incremental performance benefit. However, this benefit must be balanced against the potential cost of system down time.  It is stability that we ultimately desire and not absolute optimal performance. We do want the benefit from more accurate statistics and better query plans, but not at the risk of an unusable system. As a result, I've developed the following methodology around managing database statistics for the P6 database.  1. No Automatic Re-Gathering - The daily, weekly, or other interval of statistic gathering is unlikely to be beneficial. Quite the opposite. It is more likely to cause problems. 2. Smart Re-Gathering - The time to collect statistics is when things have changed significantly. For a new installation of P6, this is happening more often because the data is growing from a few rows to thousands and more. But for a mature system, the data is not changing significantly from week-to-week. There are times to collect statistics: New releases of the application Changes in the underlying hardware or software versions (ex. new Oracle RDBMS version) When additional user groups are added. The new groups may use the software in significantly different ways. After significant changes in the data. This may be monthly, quarterly or yearly.  3. Always Test - If you take away one thing from this post, it would be to always have a plan to test after changing statistics. In reality, statistics can be collected as often as you desire provided there are tests in place to verify that performance is the same or better. These might be automated tests or simply a manual script of application functions. 4. Have a Way Out - Never change the statistics without a way to return to the previous set. Think of the statistics as one part of the overall application code that also includes the source code--both application and RDBMS. It would be foolish to change to the new code without a way to get back to the previous version. In the final post, I will talk about the actual script I created for P6 PMDB and possible future direction for managing query performance. 

  Read the article

• Multiple Zend application code organisation

  - by user966936

  For the past year I have been working on a series of applications all based on the Zend framework and centered on a complex business logic that all applications must have access to even if they don't use all (easier than having multiple library folders for each application as they are all linked together with a common center). Without going into much detail about what the project is specifically about, I am looking for some input (as I am working on the project alone) on how I have "grouped" my code. I have tried to split it all up in such a way that it removes dependencies as much as possible. I'm trying to keep it as decoupled as I logically can, so in 12 months time when my time is up anyone else coming in can have no problem extending on what I have produced. Example structure: applicationStorage\ (contains all applications and associated data) applicationStorage\Applications\ (contains the applications themselves) applicationStorage\Applications\external\ (application grouping folder) (contains all external customer access applications) applicationStorage\Applications\external\site\ (main external customer access application) applicationStorage\Applications\external\site\Modules\ applicationStorage\Applications\external\site\Config\ applicationStorage\Applications\external\site\Layouts\ applicationStorage\Applications\external\site\ZendExtended\ (contains extended Zend classes specific to this application example: ZendExtended_Controller_Action extends zend_controller_Action ) applicationStorage\Applications\external\mobile\ (mobile external customer access application different workflow limited capabilities compared to full site version) applicationStorage\Applications\internal\ (application grouping folder) (contains all internal company applications) applicationStorage\Applications\internal\site\ (main internal application) applicationStorage\Applications\internal\mobile\ (mobile access has different flow and limited abilities compared to main site version) applicationStorage\Tests\ (contains PHP unit tests) applicationStorage\Library\ applicationStorage\Library\Service\ (contains all business logic, services and servicelocator; these are completely decoupled from Zend framework and rely on models' interfaces) applicationStorage\Library\Zend\ (Zend framework) applicationStorage\Library\Models\ (doesn't know services but is linked to Zend framework for DB operations; contains model interfaces and model datamappers for all business objects; examples include Iorder/IorderMapper, Iworksheet/IWorksheetMapper, Icustomer/IcustomerMapper) (Note: the Modules, Config, Layouts and ZendExtended folders are duplicated in each application folder; but i have omitted them as they are not required for my purposes.) For the library this contains all "universal" code. The Zend framework is at the heart of all applications, but I wanted my business logic to be Zend-framework-independent. All model and mapper interfaces have no public references to Zend_Db but actually wrap around it in private. So my hope is that in the future I will be able to rewrite the mappers and dbtables (containing a Models_DbTable_Abstract that extends Zend_Db_Table_Abstract) in order to decouple my business logic from the Zend framework if I want to move my business logic (services) to a non-Zend framework environment (maybe some other PHP framework). Using a serviceLocator and registering the required services within the bootstrap of each application, I can use different versions of the same service depending on the request and which application is being accessed. Example: all external applications will have a service_auth_External implementing service_auth_Interface registered. Same with internal aplications with Service_Auth_Internal implementing service_auth_Interface Service_Locator::getService('Auth'). I'm concerned I may be missing some possible problems with this. One I'm half-thinking about is a config.ini file for all externals, then a separate application config.ini overriding or adding to the global external config.ini. If anyone has any suggestions I would be greatly appreciative. I have used contextswitching for AJAX functions within the individual applications, but there is a big chance both external and internal will get web services created for them. Again, these will be separated due to authorization and different available services. \applicationstorage\Applications\internal\webservice \applicationstorage\Applications\external\webservice

  Read the article

• Making user input/math on data fast, unlike excel type programs

  - by proGrammar

  I'm creating a research platform solely for myself to do some research on data. Programs like excel are terribly slow for me so I'm trying to come up with another solution. Originally I used excel. A1 was the cell that contained the data and all other cells in use calculated something on A1, or on other cells, that all could be in the end traced to A1. A1 was like an element of an array, I then I incremented it to go through all my data. This was way too slow. So the only other option I found originally was to hand code in c# the calculations inside a loop. Then I simply recompiled each time I changed my math. This was terribly slow to do and I had to order everything correctly so things would update correctly (dependencies). I could have also used events, but hand coding events for each cell like calculation would also be very slow. Next I created an application to read Excel and to perfectly imitate it. Which is what I now use. Basically I write formulas onto a fraction of my data to get live results inside excel. Then my program reads excel, writes another c# program, compiles it, and runs that program which runs my excel created formulas through a lot more data a whole lot faster. The advantage being my application dependency sorts everything (or I could use events) so I don't have to (like excel does) And of course the speed. But now its not a single application anymore. Instead its 2 applications, one which only reads my formulas and writes another program. The other one being the result which only lives for a short while before I do other runs through my data with different formulas / settings. So I can't see multiple results at one time without introducing even more programs like a database or at least having the 2 applications talking to each other. My idea was to have a dll that would be written, compiled, loaded, and unloaded again and again. So a self-updating program, sort of. But apparently that's not possible without another appdomain which means data has to be marshaled to be moved between the appdomains. Which would slow things down, not for summaries, but for other stuff I need to do with all my data. I'm also forgetting to mention a huge problem with restarting an application again and again which is having to reload ALL my data into memory again and again. But its still a whole lot faster than excel. I'm really super puzzled as to what people do when they want to research data fast. I'm completely unable to have a program accept user input and having it fast. My understanding is that it would have to do things like excel which is to evaluate strings again and again. So my only option is to repeatedly compile applications. Do I have a correct understanding on computer science? I've only just began programming, and didn't think I would have to learn much to do some simple math on data. My understanding is its either compiling my user defined stuff to a program or evaluating them from a string or something stupid again and again. And my only option is to probably switch operating systems or something to be able to have a program compile and run itself without stopping (writing/compiling dll, loading dll to program, unloading, and repeating). Can someone give me some idea on how computers work? Is anything better possible? Like a running program, that can accept user input and compile it and then unload it later? I mean heck operating systems dont need to be RESTARTED with every change to user input. What is this the cave man days? Sorry, it's just so super frustrating not knowing what one can do, and can't do. If only I could understand and learn this stuff fast enough.

  Read the article

• Is there any kind of established architecture for browser based games?

  - by black_puppydog

  I am beginning the development of a broser based game in which players take certain actions at any point in time. Big parts of gameplay will be happening in real life and just have to be entered into the system. I believe a good kind of comparison might be a platform for managing fantasy football, although I have virtually no experience playing that, so please correct me if I am mistaken here. The point is that some events happen in the program (i.e. on the server, out of reach for the players) like pulling new results from some datasource, starting of a new round by a game master and such. Other events happen in real life (two players closing a deal on the transfer of some team member or whatnot - again: have never played fantasy football) and have to be entered into the system. The first part is pretty easy since the game masters will be "staff" and thus can be trusted to a certain degree to not mess with the system. But the second part bothers me quite a lot, especially since the actions may involve multiple steps and interactions with different players, like registering a deal with the system that then has to be approved by the other party or denied and passed on to a game master to decide. I would of course like to separate the game logic as far as possible from the presentation and basic form validation but am unsure how to do this in a clean fashion. Of course I could (and will) put some effort into making my own architectural decisions and prototype different ideas. But I am bound to make some stupid mistakes at some point, so I would like to avoid some of that by getting a little "book smart" beforehand. So the question is: Is there any kind of architectural works that I can read up on? Papers, blogs, maybe design documents or even source code? Writing this down this seems more like a business application with business rules, workflows and such... Any good entry points for that? EDIT: After reading the first answers I am under the impression of having made a mistake when including the "MMO" part into the title. The game will not be all fancy (i.e. 3D or such) on the client side and the logic will completely exist on the server. That is, apart from basic form validation for the user which will also be mirrored on the server side. So the target toolset will be HTML5, JavaScript, probably JQuery(UI). My question is more related to the software architecture/design of a system that enforces certain rules. Separation of ruleset and presentation One problem I am having is that I want to separate the game rules from the presentation. The first step would be to make an own module for the game "engine" that only exposes an interface that allows all actions to be taken in a clean way. If an action fails with regard to some pre/post condition, the engine throws an exception which is then presented to the user like "you cannot sell something you do not own" or "after that you would end up in a situation which is not a valid game state." The problem here is that I would like to be able to not even present invalid action in the first place or grey out the corresponding UI elements. Changing and tweaking the ruleset Another big thing is the ruleset. It will probably evolve over time and most definitely must be tweaked. What's more, it should be possible (to a certain extent) to build a ruleset that fits a specific game round, i.e. choosing different kinds of behaviours in different aspects of the game. This would do something like "we play it with extension A today but we throw out extension B." For me, this screams "Architectural/Design pattern" but I have no idea on who might have published on something like this, not even what to google for.

  Read the article

• I need help with 2D collision response (of stacking rotating polygons, with friction and gravity, for a game)

  - by Register Sole

  Hi I am looking for suggestions on how to write a collision response for game programming purpose (so not a scientific simulation). I am dealing with 2D polygons that are rotating, and I want them to be able to stack. I also want friction and gravity. I have a detection mechanism that returns the separating axis, how long the polygons are overlapping, and up to 2 points of contact. For the response, I am currently using an impulse-based response, which main idea is: find the separating axis, length of overlap, and the point of contact (if there are two, pick a random point between to simulate averaged force. i believe there are better ways than this) separate the object (modifying their positions, taking into account of their masses. i do not separate them completely though, to keep track that they are colliding to reduce jitter) calculate normal force based on the coefficient of restitution as if there is no friction. calculate friction, as if there is no normal force. I also assume that the direction of the friction is the same throughout the collision. apply the two forces (which result in a rather inaccurate result, since each force is calculated as if the other is not present. for non-rotating bodies though, this method is exact) I am aware that this method requires the coefficient of friction to be sufficiently small due to the assumption that the direction of friction stays the same in a collision. Also, the result is visually satisfying if gravity is not present. However, when there is gravity, objects on ground jitter and drift (even with zero coefficient of restitution)! It also happens for stacking objects. Larger coefficient of restitution and gravity increase the jittering. I hope you can help me with this. Some things i would like to know more about is how to handle collision with two point of contacts (how to end up having an object sitting still on the ground?), how to reduce, and prevent if possible, jitter and drift (do people use the most accurate method possible, or is there a trick to overcome this?), and how to handle multiple objects collision (for example, in the case of stacking objects, how do I check collisions between all of them and keep them all stable at every frame so they don't jitter?). A total reformulation of my algorithm is also welcomed, as long as it works. Another thing to note is that I am not making a Physics game, so I only need a visually satisfying response (though a realistic response is preferable, if it is not performance-heavy). But surely jittering and drifting objects on flat ground are not at all acceptable. In addition, I am a Physics student, so feel free to talk about impulse and whatever needed. Finally, I'm sorry for the long post. I tried to be as concise as I can. Thank you for reading it! EDIT It seems what I didn't manage to come up all this time is to separate resting contact as a class of its own and how to solve them. Currently reading the paper suggested by Jedediah. More suggestions on the topic are welcome :) CASE CLOSED After reading various papers referenced in the paper, successfully implemented simultaneous impulse method (referring to the original paper by Erin Catto, [Catt05]). Thanks maaaan!! The paper is wonderful. The current system is visibly much better than the previous. Still haven't separated resting contact as a class of its own though, which brings me to my next question. Love you all! Haha (sorry, I'm just so happy thanks to you).

  Read the article

• UnauthorizedAccessException on MemoryMappedFile in C# 4.

  - by Kevin Nisbet

  Hey, I wanted to play around with using a MemoryMappedFile to access an existing binary file. If this even at all possible or am I a crazy person? The idea would be to map the existing binary file directly to memory for some preferably higher-speed operations. Or to atleast see how these things worked. using System.IO.MemoryMappedFiles; System.IO.FileInfo fi = new System.IO.FileInfo(@"C:\testparsercap.pcap"); MemoryMappedFileSecurity sec = new MemoryMappedFileSecurity(); System.IO.FileStream file = fi.Open(System.IO.FileMode.Open, System.IO.FileAccess.ReadWrite, System.IO.FileShare.ReadWrite); MemoryMappedFile mf = MemoryMappedFile.CreateFromFile(file, "testpcap", fi.Length, MemoryMappedFileAccess.Read, sec, System.IO.HandleInheritability.Inheritable, true); MemoryMappedViewAccessor FileMapView = mf.CreateViewAccessor(); PcapHeader head = new PcapHeader(); FileMapView.Read<PcapHeader>(0, out head); I get System.UnauthorizedAccessException was unhandled (Message=Access to the path is denied.) on the mf.CreateViewAccessor() line. I don't think it's file-permissions, since I'm running as a nice insecure administrator user, and there aren't any other programs open that might have a read-lock on the file. This is on Vista with UAC disabled. If it's simply not possible and I missed something in the documentation, please let me know. I could barely find anything at all referencing this feature of .net 4.0 Thanks!

  Read the article

• How can I get a Silverlight application to check for an update and ask user to upgrade?

  - by Edward Tanguay

  I have made an out-of-browser silverlight application which I want to automatically update every time there is a new .xap file uploaded to the server. When the user right-clicks the application and clicks on Updates, the default is set to "Check for updates, but let me choose whether to download and install them": This leads me to believe that it is possible to make my Silverlight application automatically detect if there is a new .xap file present on the server, and if there is, the Silverlight client will automatically ask the user if he would like to install it. This however is not the case. I upload a new .xap file and the Silverlight application does nothing. Even if I add this to my App.xaml.cs: -- private void Application_Startup(object sender, StartupEventArgs e) { this.RootVisual = new BaseApp(); if (Application.Current.IsRunningOutOfBrowser) { Application.Current.CheckAndDownloadUpdateAsync(); } } and update the .xap file, the Silverlight application does nothing. This information enabled me to check if there is an update and if so, tell the user to restart the application, but when he restarts the application, nothing happens: -- private void Application_Startup(object sender, StartupEventArgs e) { this.RootVisual = new BaseApp(); if (Application.Current.IsRunningOutOfBrowser) { Application.Current.CheckAndDownloadUpdateAsync(); Application.Current.CheckAndDownloadUpdateCompleted += new CheckAndDownloadUpdateCompletedEventHandler(Current_CheckAndDownloadUpdateCompleted); } } void Current_CheckAndDownloadUpdateCompleted(object sender, CheckAndDownloadUpdateCompletedEventArgs e) { if (e.UpdateAvailable) { MessageBox.Show("An application update has been downloaded. " + "Restart the application to run the new version."); } else if (e.Error != null && e.Error is PlatformNotSupportedException) { MessageBox.Show("An application update is available, " + "but it requires a new version of Silverlight. " + "Visit the application home page to upgrade."); } else { //no new version available } } How do I make my Silverlight application check, each time it starts, if there is a new .xap file, and if there is, pass control to the Silverlight client to ask the user if he wants to download it, as the above dialogue implies is possible?

  Read the article

• Upload file in Android webview

  - by Sunny

  I have a html form like this <form data-ajax="false" action='UserPhoto.php' class="settings" method='POST' enctype='multipart/form-data' > <input type='file' style="height:25px" name='photo' /> <input type='hidden' name='task' value='upload'> <input type='hidden' name='file_size' value='5000000'> and I want to upload it by using webView posturl function, is it possible? as I know posturl can send String data by this way String value1 = "persistent=1"; String value2 = "&email="+ 2nd_value; String value3 = "&password="+ 3rd_value; String postData = value1+value2+value3; webView.postUrl("http://www.abc.php",EncodingUtils.getBytes(postData, "BASE64")); but is it possible for me to post .png together with some string values? and I know another method using this way to upload photo conn.setRequestProperty("Connection", "Keep-Alive"); conn.setRequestProperty("ENCTYPE", "multipart/form-data"); conn.setRequestProperty("Content-Type", "multipart/form-data;boundary=" + boundary); conn.setRequestProperty("photo", fileName); but this way doesn't communicate with webview, I need to post the photo using webview as user session is kept with it. Thanks for helping.

  Read the article

• Unable to determine the provider name for connection of type 'System.Data.SqlServerCe.SqlCeConnectio

  - by Hobbes1312

  Hi, i am using the Ado.Net Entity Framework with Code Only (Tutorial at: ADO.NET team blog) and i want to be as much database independent as possible. In my first approach i just want to go for Sql Express and Sql Compact databases. With Sql Express everthing works fine but with Sql Compact i get the exception mentioned in my question. Does anybody knows if it is possible to connect to Sql Compact with the Code Only approach? (with a generated .edmx file for a Sql Compact database everthing works fine, but i want to use code only!) Here is some code: My Class which is building the DataContext: public class DataContextBuilder : IDataContextBuilder { private readonly DbProviderFactory _factory; public DataContextBuilder(DbProviderFactory factory) { _factory = factory; } #region Implementation of IDataContextBuilder public IDataContext CreateDataContext(string connectionString) { var builder = new ContextBuilder<DataContext>(); RegisterConfiguration(builder); var connection = _factory.CreateConnection(); connection.ConnectionString = connectionString; var ctx = builder.Create(connection); return ctx; } #endregion private void RegisterConfiguration(ContextBuilder<DataContext> builder) { builder.Configurations.Add(new PersonConfiguration()); } } The line var ctx = builder.Create(connection); is throwing the exception. The IDataContext is just a simple Interface for the ObjectContext: public interface IDataContext { int SaveChanges(); IObjectSet<Person> PersonSet { get; } } My connection string is configured in the app.config: <connectionStrings> <add name="CompactConnection" connectionString="|DataDirectory|\Test.sdf" providerName="System.Data.SqlServerCe.3.5" /> </connectionStrings> And the build action is started with var cn = ConfigurationManager.ConnectionStrings["CompactConnection"]; var factory = DbProviderFactories.GetFactory(cn.ProviderName); var builder = new DataContextBuilder(factory); var context = builder.CreateDataContext(cn.ConnectionString);

  Read the article

• IIS7 Mixed Mode Authentication

  - by drachenstern

  We're getting ready to start migrating some of our IIS6 sites to IIS7, and the application currently uses Forms Authentication. We have started getting some requests from various sites to use the Windows Authentication for the users. While this is easy enough to implement (and I've shown internally that there is no issue with the app, as expected) the question then is how to continue to keep Forms authentication for when Integrated Windows doesn't work. I've seen several walkthroughs on how to have it configured on IIS6, and I could do the same thing on IIS7, but then I have to turn on Classic Mode processing. Any solution should also be back portable to IIS6, if possible, to keep the build tree simple. So what are my options on this? Do I setup the app with Integrated Windows Authentication in IIS7, Forms Auth in the web.config, and redirect 401 errors to an "error page" allowing them to login using forms, then back to the regular app? The case when Forms is likely to be needed is going to be reserved for Contract workers, our support staff, and if someone needs to access it on their site from their Extranet. So primarily it's for our staff to login to check functionality and confirm bug reports. I suggested we just maintain that for our support staff to work, we need a Windows login that will always be live, and then we'll just enforce local responsibility on who can login to the site, but I'm told that we would do better to have Forms Authentication. Any thoughts? I can post some of the links of the articles I've already read through if that would help the forum better narrow my needs. Many thanks. tl;dr: How to do mixed mode authentication (forms, windows) in IIS7 without changing to classic pipeline and still be able to use the build in IIS6 if possible.

  Read the article

• Haskell: 'No instance for' arising from a trivial usage of Regex library

  - by artemave

  Following the (accepted) answer from this question, I am expecting the following to work: Prelude Text.Regex.Posix Text.Regex.Base.RegexLike Text.Regex.Posix.String> makeRegex ".*" (makeRegex is a shortcut for makeRegexOpts with predefined options) However, it doesn't: <interactive>:1:0: No instance for (RegexMaker regex compOpt execOpt [Char]) arising from a use of `makeRegex' at <interactive>:1:0-13 Possible fix: add an instance declaration for (RegexMaker regex compOpt execOpt [Char]) In the expression: makeRegex ".*" In the definition of `it': it = makeRegex ".*" Prelude Text.Regex.Posix Text.Regex.Base.RegexLike Text.Regex.Posix.String> make Regex ".*"::Regex <interactive>:1:0: No instance for (RegexMaker Regex compOpt execOpt [Char]) arising from a use of `makeRegex' at <interactive>:1:0-13 Possible fix: add an instance declaration for (RegexMaker Regex compOpt execOpt [Char]) In the expression: makeRegex ".*" :: Regex In the definition of `it': it = makeRegex ".*" :: Regex And I really don't understand why. EDIT Haskell Platform 2009.02.02 (GHC 6.10.4) on Windows EDIT2 Prelude Text.Regex.Base.RegexLike Text.Regex.Posix.String> :i RegexMaker class (RegexOptions regex compOpt execOpt) => RegexMaker regex compOpt execOpt source | regex -> compOpt execOpt, compOpt -> regex execOpt, execOpt -> regex compOpt where makeRegex :: source -> regex makeRegexOpts :: compOpt -> execOpt -> source -> regex makeRegexM :: (Monad m) => source -> m regex makeRegexOptsM :: (Monad m) => compOpt -> execOpt -> source -> m regex -- Defined in Text.Regex.Base.RegexLike

  Read the article

• converting 2D mouse coordinates to 3D space in OpenGL ES

  - by Jayesh

  I want to convert mouse's current X and Y coordinates into the 3D space I have drawn in the viewport. I need to do this on the OpenGL ES platform. I found following possible solutions implemented in OpenGL, but none fits what I am looking for. I found NeHe's tutorial on doing exactly this, but in traditional OpenGL way. It uses gluUnProject. http://nehe.gamedev.net/data/articles/article.asp?article=13 Although gluUnProject is not available in OpenGL ES, its implementation seems simple enough to port back. But before calling it, we need to call glReadPixels with GL_DEPTH_COMPONENT and that is not possible in OpenGL ES. (The reason I found in this thread: http://www.khronos.org/message_boards/viewtopic.php?f=4&t=771) What I want to do is similar to picking, except that I don't want to select the object but I want exact coordinates so that I can recognize particular portion of the object that is currently under mouse cursor. I went through the Picking tutorials in this answer. http://stackoverflow.com/posts/2211312/revisions But they need glRenderMode, which I believe is absent in OpenGL ES. If you know how to solve this problem in OpenGL ES, please let me know. Thanks.

  Read the article

• Linking to MSVC DLL from MinGW

  - by IndigoFire

  I'm trying to link the LizardTech GeoExpress DSDK into my own application. I use gcc so that we can compile on for platforms. On Linux and Mac this works easily: they provide a static library (libltidsdk.a) and headers and all that we have to do is use them. Compiling for windows isn't so easy. They've built the library using Microsoft Visual Studio, and we use MinGW. I've read the MinGW FAQ, and I'm running into the problems below. The library is all C++, so my first question: is this even possible? Just linking against the dll as provided yields "undefined reference" errors for all of the C++ calls (constructors, desctructors, methods, etc). Based on the MinGW Wiki: http://www.mingw.org/wiki/MSVC%5Fand%5FMinGW%5FDLLs I should be able to use the utility reimp to convert a .lib into something useable. I've tried all of the .lib files provided by LizardTech, and they all give "invalid or corrupt import library". I've tried both version 0.4 and 0.3 of the reimp utility. Using the second method described in the wiki, I've run pexport and dlltool over the dll to get a .a archive, but that produces the same undefined references. BTW: I have read the discussion below. It left some ambiguity as to whether this is possible, and given the MinGW Wiki page it seems like this should be doable. If it is impossible, that's all I need to know. If it can be done, I'd like to know how I can get this to happen. stackoverflow.com/questions/1796209/how-to-link-to-vs2008-generated-libs-from-g Thanks!

  Read the article

• Common vulnerabilities for WinForms applications

  - by David Stratton

  I'm not sure if this is on-topic or not here, but it's so specific to .NET WinForms that I believe it makes more sense here than at the Security stackexchange site. (Also, it's related strictly to secure coding, and I think it's as on-topic as any question asking about common website vulnerabiitles that I see all over the site.) For years, our team has been doing threat modeling on Website projects. Part of our template includes the OWASP Top 10 plus other well-known vulnerabilities, so that when we're doing threat modeling, we always make sure that we have a documented process to addressing each of those common vulnerabilities. Example: SQL Injection (Owasp A-1) Standard Practice Use Stored Parameterized Procedures where feasible for access to data where possible Use Parameterized Queries if Stored Procedures are not feasible. (Using a 3rd party DB that we can't modify) Escape single quotes only when the above options are not feasible Database permissions must be designed with least-privilege principle By default, users/groups have no access While developing, document the access needed to each object (Table/View/Stored Procedure) and the business need for access. [snip] At any rate, we used the OWASP Top 10 as the starting point for commonly known vulnerabilities specific to websites. (Finally to the question) On rare occasions, we develop WinForms or Windows Service applications when a web app doesn't meet the needs. I'm wondering if there is an equivalent list of commonly known security vulnerabilities for WinForms apps. Off the top of my head, I can think of a few.... SQL Injection is still a concern Buffer Overflow is normally prevented by the CLR, but is more possible if using non-managed code mixed in with managed code .NET code can be decompiled, so storing sensitive info in code, as opposed to encrypted in the app.config... Is there such a list, or even several versions of such a list, from which we can borrow to create our own? If so, where can I find it? I haven't been able to find it, but if there is one, it would be a great help to us, and also other WinForms developers.

  Read the article

• Home automation using Arduino / XMPP client for Arduino

  - by Ashish

  I am trying to setup a system for automating certain tasks in my home. I am thinking of a solution wherein a server side application would be able to send/receive commands/data to Arduino (attached with Arduino Ethernet Shield) via the web. Here the Arduino may both act as a sensor interface to the server application or command executor interface for the server app. E.g. (user story): The overhead water tank in my house has a water level sensor attached with Arduino (attached with Arduino Ethernet Shield). Another Arduino (attached with Arduino Ethernet Shield) is attached with a relay/latch. This relay/latch is then connected to a water pump. Now the server side application on the web is able to get/receive water level information from the Arduino on the water tank. Depending on the water level information received, the web application should send suitable signals/commands to Arduino on water pump to switch 'ON' or switch 'OFF' the water pump. Now for such a system to work across the web, I am thinking of using one of the type of solutions in order of my priority: Using XMPP for communication between server application and Arduino. Using HTTP polling. Using HTTP hanging GET. For solution number 1, I need to implement a XMPP client that would reside on Arduino. Is it possible to write a XMPP client small enough to reside on an Arduino? If yes what are the minimum possible XMPP client functionality that I need to write for Arduino, so that it would be able to contact XMPP servers solutions like GTalk, etc.? For solution number 2 and 3 I need guidance in implementation. Also which solution would be cost effective and easily extendable?

  Read the article

• VS2010 - How to automatically stop compile on first compile error

  - by Ben Robbins

  {rant}First I'd like to say that this IS NOT A DUPLICATE. I've asked this question previously but it got closed as a duplicate when it isn't. This question is SPECIFIC to VS 2010 and the answers to the so-called duplicate work in VS 2008 but not in VS 2010 (at least not for me or anyone I know). So before you go closing something as a duplicate how about you read the question carefully and try the answer for yourself and see if it actually works. Apologies for the rant but there is no obvious way to contact the SO police that closed the issue or get it reopened. {/rant} At work we have a C# solution with over 80 projects. In VS 2008 we use a macro to stop the compile as soon as a project in the solution fails to build (see this question for several options for VS 2005 & VS 2008: http://stackoverflow.com/questions/134796/how-to-automatically-stop-visual-c-build-at-first-compile-error). Is it possible to do the same in VS 2010? What we have found is that in VS 2010 the macros don't work (at least I couldn't get them to work) as it appears that the environment events don't fire in VS 2010. The default behaviour is to continue as far as possible and display a list of errors in the error window. I'm happy for it to stop either as soon as an error is encountered (file-level) or as soon as a project fails to build (project-level). Answers for VS 2010 only please. If the macros do work then a detailed explanation of how to configure them for VS 2010 would be appreciated. Thanks.

  Read the article

• Silverlight 4 - MVC 2 ASP.NET Membership integration "single sign on"

  - by Scrappydog

  Scenario: I have an ASP.NET MVC 2 site using ASP.NET Forms Authentication. The site includes a Silverlight 4 application that needs to securely call internal web services. The web services also need to be publically exposed for third party authenticated access. Challenges: Securely accessing webservices from Silverlight using the current users identity without requiring the user to re-login in in the Silverlight application. Providing a secure way for third party applications to access the same webservices the same users credentials, ideally with out using ASP.NET Forms Authentication. Additional details and limitations: This application is hosted in Azure. We would rather NOT use RIA Services if at all possible. Solutions Under Consideration: I think that if the webservices are part of the same MVC site that hosts the Silverlight application then forms authentication should probably "just work" from Silverlight based on the users forms auth cookies. But this seems to rule out the possibility of hosting the webservices seperately (which is desirable in our scenario). For third-party access to the web services I'm guessing that seperate endpoints with a different authenication solution is probably the right answer, but I would rather only support one version of the services if possible... Questions: Can anybody point me towards any sample applications that implements something like this? How would you recommend implementing this solution?

  Read the article

• TreeGrid in GXT

  - by aTory

  Problem I'm trying to create an asynchronously updating TreeGrid in GXT but encountering issues. The first issue is that I believe the documentation is 'piss poor', at best.. therefore any chance of learning without using 'word of mouth' seems ridiculous. Instead of moaning any further, I shall inform you what I'd LIKE to do and then hopefully you can tell me if what i want is possible. Example knowledge of Football is recommended here I have a few Async services where: getLeagues() getTeams(League) getPlayers(League,Team) getPosition(League,Team,Player) I'd like to have a grid where once it renders, it makes a call to 'getLeagues', where by the server will respond with a bunch of leagues that are currently active on the server... these will be the 'root node' of the TreeGrid. Then, from here you can expand each league to show the teams, right down to the players and then their positions. I'd like to Create a TreeGrid which has a 'listener' on each node, waiting to asynchronously call the server on request and propogate the tree from here, however I'm not sure if this is possible. Can anybody advise? I'm finding all these Models, BaseTreeModels, TreeStores nauseating.

  Read the article

• MVC2 Apps (and others) sharing WCF services and authentication

  - by stupid-phil

  Hi, I've seen several similar scenarios explained here but not my particular one. I wonder if someone could tell me which direction to go in? I am developing two (and more later) MVC2 apps. There will also be another (thicker) client later on (WPF or Silverlight, TBD). These all need to share the same authentication. For the MVC2 apps they (preferably) need to be single log on - ie if a user logs in to one MVC2 app, they should be authorised on the other, as long as the cookie hasn't timed out. Forms authentication is to be used. All the apps need to use common business functionality and perform db access via a common WCF Service App. It would be nice (I think) if the WCF is not publicly accessible (ie blocked behind FW). The thicker client could use an additional service layer to access the Common WCF App. What this should look like is: MVCApp1 - WCFAppCommon MVCApp2 - WCFAppCommon ThickClient - WCFApp2 - WCFAppCommon Is it possible to carry out all the authentication/authorization in the WCFAppCommon? Otherwise I think I'll have to repeat all the security logic in the MVCApps and WCFApp2, whereas, to me, it seems to sit naturally in WCFAppCommon. On the otherhand, it seems if I authenticate/authorize in WCFAppCommon, I wouldn't be able to use Forms Authentication. Where I've seen possible solutions (that I haven't tried yet) they seem much more complex than Forms Authentication and a single DB. Any help appreciated, Phil

  Read the article

• How to do proper Unicode and ANSI output redirection on cmd.exe?

  - by Sorin Sbarnea

  If you are doing automation on windows and you are redirecting the output of different commands (internal cmd.exe or external, you'll discover that your log files contains combined Unicode and ANSI output (meaning that they are invalid and will not load well in viewers/editors). Is it is possible to make cmd.exe work with UTF-8? This question is not about display, s about stdin/stdout/stderr redirection and Unicode. I am looking for a solution that would allow you to: redirect the output of the internal commands to a file using UTF-8 redirect output of external commands supporting Unicode to the files but encoded as UTF-8. If it is impossible to obtain this kind of consistence using batch files, is there another way of solving this problem, like using python scripting for this? In this case, I would like to know if it is possible to do the Unicode detection alone (user using the scripting should not remember if the called tools will output Unicode or not, it will just expect to convert the output to UTF-8. For simplicity we'll assume that if the tool output is not-Unicode it will be considered as UTF-8 (no codepage conversion).

  Read the article

< Previous Page | 384 385 386 387 388 389 390 391 392 393 394 395  | Next Page >