Search Results

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

facebook twitter digg google delicious technorati stumbleupon myspace wordpress linkedin gmail igoogle windows live tumblr viadeo yahoo buzz yahoo mail yahoo bookmarks favorites email print

Page 596/1075 | < Previous Page | 592 593 594 595 596 597 598 599 600 601 602 603  | Next Page >

  • How to call functions inside a C dll which take pointers as arguments from C#

    - by AndrejaKo
    Hi people, this is my first post here! I'm trying to make a windows forms program using C# which will use a precompiled C library. It will access a smart card and provide output from it. For the library, I have a .dll, .lib and .h and no source. In the .h file there are several structs defined. Most interesting functions of the .dll expect pointers to allocated structs as arguments. I've been calling functions inside the .dll like this: For example function EID_API int WINAPI EidStartup(int nApiVersion); would be called like this [DllImport("CelikApi.dll")]//the name of the .dll public static extern int EidStartup(int nApiVersion); Now my problem is that I can't find equivalent of C's pointers which point to dynamically allocated structures in memory in C#, so I don't know what to pass as argument to functions which take C pointers. I don't have much experience in C#, but to me its use looked as the easiest way of making the program I need. I tried with C++, but Visual Studio 2010 doesn't have IntelliSense for C++/CLR. If you can point me to something better, feel free to do so.

    Read the article

  • C++ Virtual Constructor, without clone()

    - by Julien L.
    I want to perform "deep copies" of an STL container of pointers to polymorphic classes. I know about the Prototype design pattern, implemented by means of the Virtual Ctor Idiom, as explained in the C++ FAQ Lite, Item 20.8. It is simple and straightforward: struct ABC // Abstract Base Class { virtual ~ABC() {} virtual ABC * clone() = 0; }; struct D1 : public ABC { virtual D1 * clone() { return new D1( *this ); } // Covariant Return Type }; A deep copy is then: for( i = 0; i < oldVector.size(); ++i ) newVector.push_back( oldVector[i]->clone() ); Drawbacks As Andrei Alexandrescu states it: The clone() implementation must follow the same pattern in all derived classes; in spite of its repetitive structure, there is no reasonable way to automate defining the clone() member function (beyond macros, that is). Moreover, clients of ABC can possibly do something bad. (I mean, nothing prevents clients to do something bad, so, it will happen.) Better design? My question is: is there another way to make an abstract base class clonable without requiring derived classes to write clone-related code? (Helper class? Templates?) Following is my context. Hopefully, it will help understanding my question. I am designing a class hierarchy to perform operations on a class Image: struct ImgOp { virtual ~ImgOp() {} bool run( Image & ) = 0; }; Image operations are user-defined: clients of the class hierarchy will implement their own classes derived from ImgOp: struct CheckImageSize : public ImgOp { std::size_t w, h; bool run( Image &i ) { return w==i.width() && h==i.height(); } }; struct CheckImageResolution; struct RotateImage; ... Multiple operations can be performed sequentially on an image: bool do_operations( std::vector< ImgOp* > v, Image &i ) { std::for_each( v.begin(), v.end(), /* bind2nd(mem_fun(&ImgOp::run), i ...) don't remember syntax */ ); } int main( ... ) { std::vector< ImgOp* > v; v.push_back( new CheckImageSize ); v.push_back( new CheckImageResolution ); v.push_back( new RotateImage ); Image i; do_operations( v, i ); } If there are multiple images, the set can be split and shared over several threads. To ensure "thread-safety", each thread must have its own copy of all operation objects contained in v -- v becomes a prototype to be deep copied in each thread.

    Read the article

  • What is the best approach to 2D collision detection on the iPhone?

    - by Magic Bullet Dave
    Been working on this problem of collision detection and there appears to be 3 main approaches I could take: Sprite and mask approach. (AND the overlap of the sprites and check for a non-zero number in the resulting sprite pixel data). Bounding circles, rectangles or polygons. (Create one or more shapes that enclose the sprites and do the basic maths to check for overlaps). Use an existing sprite library. The first approach, even though it would have been the way I would have done it in the old days of 16x16 sprite blocks, it appears that there just isn’t an easy way of getting at the individual image pixel data and/or alpha channel within Quartz (or OPENGL for that matter). Detecting the overlap of the bounding box is easy, but then creating a 3rd image from the overlap and then testing it for pixels is complicated and my gut feel is that even if we could get it to work would be slow. Am I missing something neat here? The second approach involves dividing up our sprites into several polygons and testing them for overlaps. The more polygons the more accurate the collision detection. The benefit is that it is fast, and can be accurate. The downside is it makes the sprite creation more complicated. i.e., we have to create the polygons for each sprite. For speed the best approach is to create a tree of polygons. The 3rd approach I’m not sure about as it involves buying code (or using an open source licence). I am not sure what the best library to use is or whether this would make life easier or give us a problem integrating this into our app. So in short I am favouring the polygon and tree approach and would appreciate you views on this before I go and write lots of code. Best regards Dave

    Read the article

  • Sproutcore: Changing css properties on mouse events

    - by greg
    In sproutcore I'm trying to change the border thickness of a div when a user mouses over it. All the other code is working but I can't find how to either access the css properties directly or attach a new classname to the div. borderDiv: SC.View.design({ layout:{top:60, left:60, width: 400, height: 525}, classNames:"panel", mouseEntered: function(evt) { alert("this is working"); // // No idea what to put here to change css properties // return YES } })

    Read the article

  • What is the best way to create a wizard for web?

    - by Yan
    I want to create a wizard that includes a few steps, that in the final steps we need to include all the steps and save to the data base. What is the best design to do this ? Is there an implementation for jquery ? Do I need to save the steps in session till the final save ?

    Read the article

  • Creating futures using Apple's GCD

    - by jer
    I'm working on a library which implements the actor model on top of Grand Central Dispatch (specifically the C level API libdispatch). Basically a brief overview of my system is as such: Communication happens between actors using messages Multicast communication only (one actor to many actors) Senders and receivers are decoupled from one another using a blackboard where messages are pushed to. Messages are sent in the default queue asynchronously using dispatch_group_async() once a message gets pushed onto the blackboard. I'm trying to implement futures in the language right now, so I've created a new type which holds some information: A group of its own The value being 'returned' However, I have a problem since dispatch_block_t is of type void (^)(void) so it doesn't return anything. So my idea of in my future_new() function of setting up another group which can be used to execute a block returning a result, which I can store in my "value" member in my future_t structure, isn't going to work. The rest of the futures implementation is very clear, except it all depends on being able to get the value into the future back from the actor, acting on the message. When using the library, it would greatly reduce its usefulness if I had to ask users (and myself) to be aware when futures were going to be used by other parts of the system—It just isn't practical. I'm wondering if anyone can think of a way around this?

    Read the article

  • How do I define and standardize units in my 3D app?

    - by Omega
    I'm starting to design my object graph for an OpenGL ES 1.1 on Android. What's advisable when it comes to actually drawing my triangles when it comes to controlling their size? Should I store all the vertices in units relative to each other and then multiply them by a value I pass during a draw(GL10 gl)? Would this approach have any impact when it comes time to do frustum culling?

    Read the article

  • How to implement an interface class using the non-virtual interface idiom in C++?

    - by andreas buykx
    Hi all, In C++ an interface can be implemented by a class with all its methods pure virtual. Such a class could be part of a library to describe what methods an object should implement to be able to work with other classes in the library: class Lib::IFoo { public: virtual void method() = 0; }; : class Lib::Bar { public: void stuff( Lib::IFoo & ); }; Now I want to to use class Lib::Bar, so I have to implement the IFoo interface. For my purposes I need a whole of related classes so I would like to work with a base class that guarantees common behavior using the NVI idiom: class FooBase : public IFoo // implement interface IFoo { public: void method(); // calls methodImpl; private: virtual void methodImpl(); }; The non-virtual interface (NVI) idiom ought to deny derived classes the possibility of overriding the common behavior implemented in FooBase::method(), but since IFoo made it virtual it seems that all derived classes have the opportunity to override the FooBase::method(). If I want to use the NVI idiom, what are my options other than the pImpl idiom already suggested (thanks space-c0wb0y).

    Read the article

  • How to get all usages/references of control in DotNetNuke?

    - by macias
    Sorry for lame question but I am literally starting with DNN. When you are in admin/design mode you can list all modules used, and when you click on module at the end you will see the list of controls used in this module with info about filename of the source. The problem I have is in reverse -- I already know the filename with source, I would like to list all modules which use this control. How to do it?

    Read the article

  • LINQ VB.NET variable not found when looping through grouped query

    - by Ed Sneller
    I'm trying to do the following LINQ grouping, which works in the debugger (the results are populated in the GroupedOrders object. But VS 2008 gives me the following error at design time... Name 'x' is not declared Dim GroupedOrders = (From m In thisConsultant.orders _ Group m By Key = m.commCode Into Group _ Select commCode = Key, orders = Group) For Each x In GroupedOrders Next VS 2008 gives me the following error,

    Read the article

  • jQuery cycle floats on top of other content

    - by Angie Dubis
    I tried to replace my Flash video with a jQuery cycle. The cycle works, but the images will not stay in the editable region I placed them in. Instead they are floating on top of other content. Any ideas? This is happening on the home page of massageeducator.com There are 2 cycles on the page. “Slideshow1” and “slideshow2”. “slideshow1” works perfectly. The only thing I did differently was set up “slideshow2” as a library item since it will appear on every page, but added function code manually. I tried adding code and images via the template and had the same issue. I also tried adding both the function code and slideshow to each page instead of library item - same problem. I have both slide shows pointing to the same jquery.cycle.lite.1.0.js. Should I rename this .js file and have each cycle point to a different file? I am new to jQuery so any help is appreciated. I can't seem to post my code due to the spam filters in here!

    Read the article

  • SVG Parser in Javascript

    - by jsight
    I believe that at one point, I saw a TinySVG implementation that worked in the browser, using the canvas element as the backend. I found a few sites that appeared to indicate it was at http://fuchsia-design.com/CanvaSVG/, however, that site appears to no longer exist. Is this project (or a similar one) still on the web anywhere?

    Read the article

  • Linq-to-SQL: how many datacontexts ?

    - by sh00
    I have a SQL Server 2008 database with 300 tables. The application I have to design is an Windows Forms app, .NET 3.5, C#. Which is the best way to work with Linq-to-SQL ? I intend to make a datacontext for each business entity. Is there any problem ? I need to know if this way of working with Linq-to-SQL has any disadvantage or can create performance issues ? Thanks.

    Read the article

  • Is there something like a Filestorage class to store files in?

    - by nebukadnezzar
    Is there something like a class that might be used to store Files and directories in, just like the way Zip files might be used? Since I haven't found any "real" class to write Zip files (real class as in real class), It would be nice to be able to store Files and Directories in a container-like file. A perfect API would probably look like this: int main() { ContainerFile cntf("myContainer.cnt", ContainerFile::CREATE); cntf.addFile("data/some-interesting-stuff.txt"); cntf.addDirectory("data/foo/"); cntf.addDirectory("data/bar/", ContainerFile::RECURSIVE); cntf.close(); } ... I hope you get the Idea. Important Requirements are: The Library must be crossplatform anything *GPL is not acceptable in this case (MIT and BSD License are) I already played with the thought of creating an Implentation based on SQLite (and its ability to store binary blobs). Unfortunately, it seems impossible to store Directory structures in a SQLite Database, which makes it pretty much useless in this case. Is it useless to hope for such a class library?

    Read the article

  • Stale connection with Pheanstalk

    - by token47
    I'm using beanstalkd to offload some work to other machines. The setup is a bit unusual, the server is on the internet (public ip) but the consumers are behind adsl lines on some peoples homes. So there is a linux server as client going out through a dynamic ip and connecting to the server to get a job. It's all PHP and I'm using pheanstalk library. Everything runs smoothly for some time, but then the adsl changes the IP (every 24h hours the provider forces a disconnect-reconnect) the client just hangs, never to go out of "reserve". I thought that putting a timeout on the reserve would help it, but it didn't. As it seems, the client issues a command and blocks, it never checks the timeout. It just issues a reserve-with-timeout (instead of a simple reserve) and it is the servers responsibility to return a TIME_OUT as the timeout occurs. The problem is, the connection is broken (but the TCP/IP doesn't know about that yet until any of the sides try to talk to the other side) and if the client blocked reading, it will never return. The library seems to have support for some kind of timeouts locally (for example when trying to connect to server), but it does not seem to contemplate this scenario. How could I detect the stale connection and force a reconnect? Is there some kind of keepalive on the protocol (and on the pheanstalk itself)? Thanks!

    Read the article

  • SharePoint: Filtering a List that has Folders

    - by Gary McGill
    I have a SharePoint document library that has a folder structure used for organizing the documents (but also for controlling access, via permissions on the folders). The documents in the library are updated every month, and we store every month's version of the document in the same folder; there's a "month" column used for filtering that will contain values like Jan 09, Feb 09, etc. It looks like this: Title Month ----- ----- SubFolder 1 SubFolder 2 [] Interesting Facts Jan 09 [] Interesting Facts Feb 09 [] Interesting Facts Mar 09 [] Fascinating Numbers Jan 09 [] Fascinating Numbers Feb 09 ... Now, because users will generally be most interested in the 'current' month, I'd like them to be able to apply a filter, and select (say) Mar 09. However, if they do this using the built-in filtering, it also filters out the folders, and they can no longer navigate the folder hierarchy. This is no good - I want them to be able to move between folders with the filter intact, so that they don't need to keep switching it off and on again. I figured I might be able to use a custom view (selecting where type=folder or month=[month]), and to an extent that does work. However, I can only get it to work for a fixed month, whereas I need the user to be able to select the month - perhaps via a drop-down control on the page (and I don't want to create 60 views for 5 years' worth of months, nor do I want to have to create a new view every month). I thought it might be possible to create a view in code (rather than via the UI), but I've not been able to figure out how to get a dynamic value (a user-specific setting) into the CAML query. Any pointers gratefully appreciated! And by the way, I am aware of the dogma that folders are bad, and that everything should just be a list. However, having considered the alternatives, I still favour using folders - if I can solve this problem. Thanks in advance.

    Read the article

  • MSBuild / PowerShell: Copy SQL Server 2012 database to SQL Azure via BACPAC (for Continuous Integration)

    - by giveme5minutes
    I'm creating a continuous integration MSBuild script which copies a database in on-premise SQL Server 2012 to SQL Azure. Easy right? Methods After a fair bit of research I've come across the following methods: Use PowerShell to access the DAC library directly, then use the MSBuild PowerShell extension to wrap the script. This would require installing PowerShell 3 and working out how to make the MSBuild PowerShell extension work with it, as apparently MS moved the DAC API to a different namespace in the latest version of the library. PowerShell would give direct access to the API, but may require quite a bit of boilerplate. Use the sample DAC Framework Client Side Tools, which requires compiling them myself, as the downloads available from Codeplex only include the Hosted version. It would also require fixing them to use DAC 3.0 classes as they appear to currently use an earlier version of DAC. I could then call these tools from an <Exec Command="" /> in the MSBuild script. Less boilerplate and if I hit any bumps in the road I can just make changes to the source. Processes Using whichever method, the process could be either: Export from on-premise SQL Server 2012 to local BACPAC Upload BACPAC to blog storage Import BACPAC to SQL Azure via Hosted DAC Or: Export from on-premise SQL Server 2012 to local BACPAC Import BACPAC to SQL Azure via Client DAC Question All of the above seems to be quite a lot of effort for something that seems to be a standard feature... so before I start reinventing the wheel and documenting the results for all to see, is there something really obvious that I've missed here? Is there pre-written script that MS has released that I have not yet uncovered? There's an command in the GUI of SQL Server Management Studio 2012 that does EXACTLY what I'm trying to do (right click on local database, click "Tasks", click "Deploy Database to SQL Azure"). Surely if it's a few clicks in the GUI it must be a single command on the command line somewhere??

    Read the article

  • Projective transformation

    - by mcwehner
    Given two image buffers (assume it's an array of ints of size width * height, with each element a color value), how can I map an area defined by a quadrilateral from one image buffer into the other (always square) image buffer? I'm led to understand this is called "projective transformation". I'm also looking for a general (not language- or library-specific) way of doing this, such that it could be reasonably applied in any language without relying on "magic function X that does all the work for me". An example: I've written a short program in Java using the Processing library (processing.org) that captures video from a camera. During an initial "calibrating" step, the captured video is output directly into a window. The user then clicks on four points to define an area of the video that will be transformed, then mapped into the square window during subsequent operation of the program. If the user were to click on the four points defining the corners of a door visible at an angle in the camera's output, then this transformation would cause the subsequent video to map the transformed image of the door to the entire area of the window, albeit somewhat distorted.

    Read the article

  • How to prefix a positive number with plus sign in PHP

    - by user318466
    I need to design a function to return negative numbers unchanged but should add a + sign at the start of the number if its already no present. Example: Input Output ---------------- +1 +1 1 +1 -1 -1 It will get only numeric input. function formatNum($num) { # something here..perhaps a regex? } This function is going to be called several times in echo/print so the quicker the better.

    Read the article

  • Dependent properties

    - by Senthilkumar
    Hi I am new to WPF.. Can anyone tell.. What exactly the depentent properties means?.. How it differ from normal properties??? and can i edit the design page in asp 3.5 while am i running the application, because the same is possible in asp 2.0.

    Read the article

facebook twitter digg google delicious technorati stumbleupon myspace wordpress linkedin gmail igoogle windows live tumblr viadeo yahoo buzz yahoo mail yahoo bookmarks favorites email print

< Previous Page | 592 593 594 595 596 597 598 599 600 601 602 603  | Next Page >