Search Results

Search found 10366 results on 415 pages for 'const char pointer'.

Page 265/415 | < Previous Page | 261 262 263 264 265 266 267 268 269 270 271 272  | Next Page >

  • Ubuntu 13.10 Unity doesn't load after upgrade

    - by William
    Just upgraded to Ubuntu 13.10 only to find that Unity won't load (login freezes, after doing ctrl+alt+F1, logging in and then doing startx, I get a blank desktop and the mouse pointer, and nothing else). I can right click, but the only operations that work are "create new file" and "create new folder". For example, "change desktop background" doesn't work. Also, after doing a few right clicks and choosing "change desktop background", I get a warning message box: "compiz closed unexpectedly." Guest login works fine. Tried creating a new user, but I experience the same thing with the new user. Tried removing all configuration files from my home directory... same thing. Doing dconf reset -f /org/compiz/ gives an error "error spawning command line..." Doing unity --reset also gives errors. Tried uninstalling unity (and compiz) and reinstalling, but that doesn't help. Tried reconfiguring lightdm, didn't help. I don't have any proprietary drivers installed. Once again, the funny thing is that the guest session works fine.

    Read the article

  • Test-Driven Development with plain C: manage multiple modules

    - by Angelo
    I am new to test-driven development, but I'm loving it. There is, however, a main problem that prevents me from using it effectively. I work for embedded medical applications, plain C, with safety issues. Suppose you have module A that has a function A_function() that I want to test. This function call a function B_function, implemented in module B. I want to decouple the module so, as James Grenning teaches, I create a Mock module B that implements a mock version of B_function. However the day comes when I have to implement module B with the real version of B_function. Of course the two B_function can not live in the same executable, so I don't know how to have a unique "launcher" to test both modules. James Grenning way out is to replace, in module A, the call to B_function with a function pointer that can have the value of the mock or the real function according to the need. However I work in a team, and I can not justify this decision that would make no sense if it were not for the test, and no one asked me explicitly to use test-driven approach. Maybe the only way out is to generate different a executable for each module. Any smarter solution? Thank you

    Read the article

  • Debugger for file I/O development?

    - by datenwolf
    Okay, the question title may be a bit cryptic. But it aptly describes what I'm looking for: I think every experienced coder went through this numerous times: You get a binary file format specification, you implement the reader for it, and… nothing works like expected. So you run your code in the debugger, go execute through the code line by line, every header field is read in seemingly correct, but when it comes to the bulk data, offset and indices no longer match up. What would really help in this situation was a binary file viewer, that shows you the progress of your file pointer, as you step through the code, and ideally would also highlight all memory maps. Then you could see the context of the current I/O operations, most notably those darn "off-by-one" mistakes, which are even more annoying when reading a file. Implementing such a debugger should not be too hard. traces on the process' file descriptors/handles and triggers on the I/O functions, to update the display. Only: I don't know of such a kind of debugger to exist. Do I just lack knowledge about the existance of such a tool, or is there really no such thing?

    Read the article

  • Dynamic Jump spot

    - by Pasquale Sada
    I have an initial velocity V(Vx,Vy,VZ) and a spot where he stands still at S(Sx,Sy,Sz). What I'm trying to achieve is a jump on a spot E(Ex,Ey,Ez) where you have clicked on(only lower or higher spot, because I've in place a simple steering behavior for even terrains). There are no obstacle around. I've implemented a formula that can make him jump in a precise way on a spot but you need to declare an angle: the problem arise when the selected spot is straight above your head. It' pretty lame that the char hang there and can reach a thing that is 1cm above is head. I'll share the code I'm using: Vector3 dir = target - transform.position; // get target direction float h = dir.y; // get height difference dir.y = 0; // retain only the horizontal direction float dist = dir.magnitude ; // get horizontal distance float a = angle * Mathf.Deg2Rad; // convert angle to radians dir.y = dist * Mathf.Tan(a); // set dir to the elevation angle dist += h / Mathf.Tan(a); // correct for small height differences // calculate the velocity magnitude float vel = Mathf.Sqrt(dist * Physics.gravity.magnitude / Mathf.Sin(2 *a)); return vel * dir.normalized;

    Read the article

  • Which Ubuntu linux kernel tree matches my installed kernel?

    - by Rmano
    Answering a recent question, and before that, trying to see if a patch which is fundamental for my machine had been included in a kernel release, I have found the following problem: How can I match the kernel version I have for my kernel, which is [:~] % uname -a Linux samsung-romano 3.13.0-29-generic #53-Ubuntu SMP Wed Jun 4 21:00:20 UTC 2014 x86_64 x86_64 x86_64 GNU/Linux with the exact kernel source, which I suppose should be stored in http://kernel.ubuntu.com/git?p=ubuntu/linux.git;a=summary? In that page there are quite a lot of tags, for example: But none of them correspond to 3.13.0-29 which is my running kernel right now. The mapping should be in https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable, where it is said that the 3.13 Ubuntu kernel is based on 3.13.11 --- I think. But from there to finding the tree I have installed is not straightforward. Notice: I know I can install the kernel source corresponding with my installed kernel. But I do not want to install them; I would like ti have a pointer to the git tree to be able to browse it online (and check for commits, patches, etc.). The best options seems to go to linux3.13-y.review or linux3.13-y.queue, but I am unable to find where this tree are marked for the release - if I understand well the policy, in -review the patches are accumulated for testing, and in -queue accumulated for the next minor release/update --- but I am unable to find the exact release tree. I mean, a tag equivalent to 3.13.0-29 was cut here.

    Read the article

  • The most efficent ways for drawing lines all day long with OpenGL

    - by nkint
    I'd like to put a computer screen that is running an OpenGL programs in a room. It has to run all day long (not in the night). I'd like to draw lines that are slowly fading in the background. The setting is simple: a uniform color background (say, black) and colored lines (say, white) that are slowly fading out. With slowly I mean.. hours. Say that the first line I draw is with alpha 255 (fully visible), after one hours is 240. After 10 hours is 105. One line could have 250 points and there will be like 300 line in one day. For now I have done a prototype with very rudimentary method like: glBegin( GL_LINE_STRIP ); iterator = point_list.begin(); for (++iterator, end = point_list.end(); iterator != end; ++iterator) { const Vec3D &v = *iterator; glVertex2f(v.x(), v.y()); } glEnd(); More efficient method?

    Read the article

  • Select Data From XML in MS SQL Server (T-SQL)

    - by Doug Lampe
    So you have used XML to give you some schema flexibility in your database, but now you need to get some data out.  What do you do?  The solution is relatively  simple:   DECLARE @iDoc INT /* Stores a pointer to the XML document */ DECLARE @XML VARCHAR(MAX) /* Stores the content of the XML */   set @XML = (SELECT top 1 Xml_Column_Name FROM My_Table where Primary_Key_Column = 'Some Value')   EXEC sp_xml_preparedocument @iDoc OUTPUT, @XML   SELECT * FROM OPENXML(@iDoc,'/some/valid/xpath',2)                      WITH (output_column1_name varchar(50)  'xml_node_name1',                                                     output_column2_name varchar(50)  'xml_node_name2')   EXEC sp_xml_removedocument @iDoc   In this example, the XML data would look something like this:   <some>   <valid>     <xpath>       <xml_node_name1>Value1</xml_node_name1>       <xml_node_name2>Value2</cml_node_name2>     </xpath>   </valid> </some>   The resulting query should give you this:   output_column1_name    output_column2_name ------------------------------------------ Value1                 Value2   Note that in this example we are only looking at a single record at a time.  You could use a cursor to iterate through multiple records and insert the XML data into a temporary table.

    Read the article

  • Serializing network messages

    - by mtsvetkov
    I am writing a network wrapper around boost::asio and was wondering what is a good and simple way to serialize my messages. I have a message factory which can take care of dispatching the data to the correct builder, but I want to know if there are any established solutions for getting the binary data on the sender side and consequently passing the data for deserialization on the receiver end. Some options I've explored are: passing a pointer to a char[] to the serialize/deserialize functions (for serialize to write to, and deserialize to read from), but it's difficult to enforce buffer size this way; building on that, I decided to have the serialize function return a boost::asio::mutable_buffer, however ownership of the memory gets blurred between multiple classes, as the network wrapper needs to clean up the memory allocated by the message builder. I have also seen solutions involving streambuf's and stringstream's, but manipulating binary data in terms of its string representation is something I want to avoid. Is there some sort of binary stream I can use instead? What I am looking for is a solution (preferrably using boost libs) that lets the message builder dictate the amount of memory allocated during serialization and what that would look like in terms of passing the data around between the wrapper and message factory/message builders. PS. Messages contain almost exclusively built-in types and PODs and form a shallow but wide hierarchy for the sake of going through a factory. Note: a link to examples of using boost::serialization for something like this would be appreciated as I'm having difficulties figuring out the relation between it and buffers.

    Read the article

  • Desktop goes un-usable after upgrade to 12.04

    - by Tom Nail
    I have multiple Ubuntu systems connected to a KVM, one of which I recently upgraded from Ubuntu 10 to 12.04. After the upgrade, this system desktop does fine until it is allowed to go to idle (i.e., I've switched to another system on the KVM and it locks it's desktop). When I come back to it, the screen is garbled and paging across at a rate seemingly determined by the mouse. Although no pointer is visible, I can get the screen to stop paging (and just be garbled) by moving the mouse left and right. The paging will slow down and come to a stop, if I can align things carefully enough. This condition persists even when I try to go to a CLI-based login (e.g., CTRL+Alt+F1) and will continue until I reboot the machine. Unfortunately, I'm not very familiar with the Unity desktop, so I don't know where to find things to troubleshoot. A restart of lightdm doesn't change anything, so I'm wondering if this might be more hardware based( although this machine hasn't given me any trouble previously in the same setup). The .xsession-errors file has some issues with compiz, nautilus and GConf listed, but I'm not sure those are actually germane to the issue. Thanks for any help, -=Tom

    Read the article

  • What's wrong with circular references?

    - by dash-tom-bang
    I was involved in a programming discussion today where I made some statements that basically assumed axiomatically that circular references (between modules, classes, whatever) are generally bad. Once I got through with my pitch, my coworker asked, "what's wrong with circular references?" I've got strong feelings on this, but it's hard for me to verbalize concisely and concretely. Any explanation that I may come up with tends to rely on other items that I too consider axioms ("can't use in isolation, so can't test", "unknown/undefined behavior as state mutates in the participating objects", etc.), but I'd love to hear a concise reason for why circular references are bad that don't take the kinds of leaps of faith that my own brain does, having spent many hours over the years untangling them to understand, fix, and extend various bits of code. Edit: I am not asking about homogenous circular references, like those in a doubly-linked list or pointer-to-parent. This question is really asking about "larger scope" circular references, like libA calling libB which calls back to libA. Substitute 'module' for 'lib' if you like. Thanks for all of the answers so far!

    Read the article

  • How to highlight non-rectengular hotspots?

    - by HuseyinUslu
    So my question is highly related to Creating non-rectangular hotspots and detecting clicks. Yet again, I've irregular hot-spots (think the game Risk). So basically, we can detect clicks on these hot-spots easily using color key mapping as discussed in above question which I don't have any problems implementing (which is also covered here in details). The problem is about highlighting these irreguar hotspots. So let me explain the question a bit more - the above color key mapping guide uses this as a world map; then the author color-maps the imaginary countries; which we can now detect the country the pointer is over. In the same article author mentions outlining countries on mouse-over; though to get the effect, he creates unique border assets for each country - like; So for the game I'm working on I'm using the same color-key mapping idea to detect hot-spots, but I didn't like the way of highlighting hot-spots. Coloring all the hot-spots is already a great work for me - as I've 25+ hot-spots for each map - further more the need to have 25 unique border/highlight asset per hot-spot doesn't sound right. Anyone have a better idea/suggestion on highlighting these hot-spots?

    Read the article

  • 10.04 Window manager not working

    - by jackg
    Using an old mx200 128Mb AGP card. Log in ok. Sometimes the top and bottom bars do not appear, sometimes one sometimes both sometimes none. The menus on firefox/thunderbird and others disappear when I move the pointer from the menu heading to the menu itself. I can't play you tube videos, nor pacman, so the world has ended as I know it. If I type sudo metacity --replace in a terminal the window manager seems to work fine. But I don't know how to make this permanent. One option was: System menupreferencessessions In the sessions tab make sure that "automatically save changes to session" is checked. I don't have a sessions option in the preferences menu. So...? Must be a line of code in a terminal I can use to get round this. I have not upgraded to Ubuntu 11... because the graphics card is so old that I cannot get any decent screen resolutions when I do. On 10.04 I disable the Nvidia driver for the same reason and use 1024x768. Ta

    Read the article

  • Is this the most effect simple way to display a moving image? SDL2

    - by user36324
    I've looked around for tutorials on SDL2, but there isnt many so I am curious i was messing around and is this an effective way to move an image. One problem is that it drags along the image to where it moves. #include "SDL.h" #include "SDL_image.h" int main(int argc, char* argv[]) { bool exit = false; SDL_Init(SDL_INIT_EVERYTHING); SDL_Window *win = SDL_CreateWindow("Hello World!", 100, 100, 640, 480, SDL_WINDOW_SHOWN); SDL_Renderer *ren = SDL_CreateRenderer(win, -1, SDL_RENDERER_ACCELERATED | SDL_RENDERER_PRESENTVSYNC); SDL_Surface *png = IMG_Load("character.png"); SDL_Rect src; src.x = 0; src.y = 0; src.w = 161; src.h = 159; SDL_Rect dest; dest.x = 50; dest.y = 50; dest.w = 161; dest.h = 159; SDL_Texture *tex = SDL_CreateTextureFromSurface(ren, png); SDL_FreeSurface(png); while(exit==false){ dest.x++; SDL_RenderClear(ren); SDL_RenderCopy(ren, tex, &src, &dest); SDL_RenderPresent(ren); } SDL_Delay(5000); SDL_DestroyTexture(tex); SDL_DestroyRenderer(ren); SDL_DestroyWindow(win); SDL_Quit(); }

    Read the article

  • Handling game logic events by behavior components

    - by chehob
    My question continues on topic discussed here I have tried implementing attribute/behavior design and here is a quick example demonstrating the issue. class HealthAttribute : public ActorAttribute { public: HealthAttribute( float val ) : mValue( val ) { } float Get( void ) const { return mValue; } void Set( float val ) { mValue = val; } private: float mValue; }; class HealthBehavior : public ActorBehavior { public: HealthBehavior( shared_ptr< HealthAttribute > health ) : pHealth( health ) { // Set OnDamage() to listen for game logic event "DamageEvent" } void OnDamage( IEventDataPtr pEventData ) { // Check DamageEvent target entity // ( compare my entity ID with event's target entity ID ) // If not my entity, do nothing // Else, modify health attribute with received DamageEvent data } protected: shared_ptr< HealthAttribute > pHealth; }; My question - is it possible to get rid of this annoying check for game logic events? In the current implementation when some entity must receive damage, game logic just fires off event that contains damage value and the entity id which should receive that damage. And all HealthBehaviors are subscribed to the DamageEvent type, which leads to any entity possesing HealthBehavior call OnDamage() even if he is not the addressee.

    Read the article

  • Using a random string to authenticate HMAC?

    - by mrwooster
    I am designing a simple webservice and want to use HMAC for authentication to the service. For the purpose of this question we have: a web service at example.com a secret key shared between a user and the server [K] a consumer ID which is known to the user and the server (but is not necessarily secret) [D] a message which we wish to send to the server [M] The standard HMAC implementation would involve using the secret key [K] and the message [M] to create the hash [H], but I am running into issues with this. The message [M] can be quite long and tends to be read from a file. I have found its very difficult to produce a correct hash consistently across multiple operating systems and programming languages because of hidden characters which make it into various file formats. This is of course bad implementation on the client side (100%), but I would like this webservice to be easily accessible and not have trouble with different file formats. I was thinking of an alternative, which would allow the use a short (5-10 char) random string [R] rather than the message for autentication, e.g. H = HMAC(K,R) The user then passes the random string to the server and the server checks the HMAC server side (using random string + shared secret). As far as I can see, this produces the following issues: There is no message integrity - this is ok message integrity is not important for this service A user could re-use the hash with a different message - I can see 2 ways around this Combine the random string with a timestamp so the hash is only valid for a set period of time Only allow each random string to be used once Since the client is in control of the random string, it is easier to look for collisions I should point out that the principle reason for authentication is to implement rate limiting on the API service. There is zero need for message integrity, and its not a big deal if someone can forge a single request (but it is if they can forge a very large number very quickly). I know that the correct answer is to make sure the message [M] is the same on all platforms/languages before hashing it. But, taking that out of the equation, is the above proposal an acceptable 2nd best?

    Read the article

  • How to make backlight work on Acer 5732z?

    - by Dude Random21
    I want to run 12.04 on my Acer Aspire 5732z. I know from research that these computers have issues with the backlight on Ubuntu. So I tried a couple of solutions: The sudo lightdm restart method. I get no change at all. The sudo setpci -s 00:02.0 F4.B=30 method. This so far has been the most effective. I first tried it in the F1 console, right away I get the screen back, problem is going back to the desktop it goes back to being black. So I tried it from a terminal window and it works as well but as soon as I unplug my external monitor the screen turns black again and doesn't come back. If I plug the monitor back in the screen stays black and the only thing I see is the mouse pointer. From here I go back into console (which I am able to see) and reboot from there. The sudo sed -i 's/GRUB_CMDLINE_LINUX=""/GRUB_CMDLINE_LINUX="acpi_osi=Linux"/g /etc/default/grub method. This one I got no instant change and after reboot still no change. I'm open to pretty much any suggestions you may have.

    Read the article

  • Recommended formats to store bitmaps in memory?

    - by Geotarget
    I'm working with general purpose image rendering, and high-performance image processing, and so I need to know how to store bitmaps in-memory. (24bpp/32bpp, compressed/raw, etc) I'm not working with 3D graphics or DirectX / OpenGL rendering and so I don't need to use graphics card compatible bitmap formats. My questions: What is the "usual" or "normal" way to store bitmaps in memory? (in C++ engines/projects?) How to store bitmaps for high-performance algorithms, such that read/write times are the fastest? (fixed array? with/without padding? 24-bpp or 32-bpp?) How to store bitmaps for applications handling a lot of bitmap data, to minimize memory usage? (JPEG? or a faster [de]compression algorithm?) Some possible methods: Use a fixed packed 24-bpp or 32-bpp int[] array and simply access pixels using pointer access, all pixels are allocated in one continuous memory chunk (could be 1-10 MB) Use a form of "sparse" data storage so each line of the bitmap is allocated separately, reusing more memory and requiring smaller contiguous memory segments Store bitmaps in its compressed form (PNG, JPG, GIF, etc) and unpack only when its needed, reducing the amount of memory used. Delete the unpacked data if its not used for 10 secs.

    Read the article

  • Matlab: Why is '1' + 1 == 50? [migrated]

    - by phi
    Matlab has weak dynamic typing, which is what causes this weird behaviour. What I do not understand is what exactly happens, as this result really surprises me. Edit: To clarify, what I'm describing is clearly a result of Matlab storing chars in ASCII-format, which was also mentioned in the comments. I'm more interested in the way Matlab handles its variables, and specifically, how and when it assigns a type/tag to the values. Thanks. '1' is a 1-by-1 matrix of chars in matlab and '123' is a 1-by-3 matrix of chars. As expected, 1 returns a 1-by-1 double. Now if I enter '1' + 1 I get 50 as a 1-by-1 double, and if I enter '123' + 1 I get a 1-by-3 double [ 50 51 52 ] Furthermore, if I type 'a' + 1 the result is 98 in a 1-by-1 double. I assume this has to do with how Matlab stores char-variables in ascii form, but how exactly is it handling these? Are the data actually unityped and tagged, or how does it work? Thanks.

    Read the article

  • Making WatiN Wait for JQuery document.Ready() Functions to Complete

    - by Steve Wilkes
    WatiN's DomContainer.WaitForComplete() method pauses test execution until the DOM has finished loading, but if your page has functions registered with JQuery's ready() function, you'll probably want to wait for those to finish executing before testing it. Here's a WatiN extension method which pauses test execution until that happens. JQuery (as far as I can see) doesn't provide an event or other way of being notified of when it's finished running your ready() functions, so you have to get around it another way. Luckily, because ready() executes the functions it's given in the order they're registered, you can simply register another one to add a 'marker' div to the page, and tell WatiN to wait for that div to exist. Here's the code; I added the extension method to Browser rather than DomContainer (Browser derives from DomContainer) because it's the sort of thing you only execute once for each of the pages your test loads, so Browser seemed like a good place to put it. public static void WaitForJQueryDocumentReadyFunctionsToComplete(this Browser browser) { // Don't try this is JQuery isn't defined on the page: if (bool.Parse(browser.Eval("typeof $ == 'function'"))) { const string jqueryCompleteId = "jquery-document-ready-functions-complete"; // Register a ready() function which adds a marker div to the body: browser.Eval( @"$(document).ready(function() { " + "$('body').append('<div id=""" + jqueryCompleteId + @""" />'); " + "});"); // Wait for the marker div to exist or make the test fail: browser.Div(Find.ById(jqueryCompleteId)) .WaitUntilExistsOrFail(10, "JQuery document ready functions did not complete."); } } The code uses the Eval() method to send JavaScript to the browser to be executed; first to check that JQuery actually exists on the page, then to add the new ready() method. WaitUntilExistsOrFail() is another WatiN extension method I've written (I've ended up writing really quite a lot of them) which waits for the element on which it is invoked to exist, and uses Assert.Fail() to fail the test with the given message if it doesn't exist within the specified number of seconds. Here it is: public static void WaitUntilExistsOrFail(this Element element, int timeoutInSeconds, string failureMessage) { try { element.WaitUntilExists(timeoutInSeconds); } catch (WatinTimeoutException) { Assert.Fail(failureMessage); } }

    Read the article

  • Ubuntu 12.04 takes too long to boot

    - by msPeachy
    I've recently encountered the following error message: mount: mounting /dev/disk/by-uuid/3f7f5cd9d-6ea3-4da7-b5ec-**** on /root failed: Invalid argument mount: mounting /sys on /root/sys failed: No such file or directory mount: mounting /dev on /root/dev failed: No such file or directory mount: mounting /sys on /root/sys failed: No such file or directory mount: mounting /proc on /root/proc failed: No such file or directory Target file system doesn't have /sbin/init. No init found. Try passing init= bootarg. Busybox v1.18.5 (Ubuntu 1:1.18.5-1ubuntu4) built-in shell (ash) Enter 'help' for a list of built-in commands. (initramfs) _ I run sudo fsck /dev/sda2 which is the Ubuntu ext4 root partition via LiveCD. It checked and fixed the file system. The next time I boot, Ubuntu started to load with the Ubuntu logo and the dots underneath for several hours (with the mouse pointer active on the screen), I even let the computer on overnight but still it did not successfully boot or got to the login screen in the morning. I booted again with the LiveCD and checked the NTFS partitions with ntfsfix and again the NTFS partitions was checked and fixed successfully. I also edited my fstab and commented out the lines that auto-mounts the NTFS partitions. The next time I boot, it took almost 20 minutes for Ubuntu to get to the login screen, after typing the password it took an additional 10 minutes for Ubuntu to get to the desktop. On the desktop, it take several minutes to open any program, displaying the Dash alone takes 5 minutes! Is there a fix for this without having to reinstall Ubuntu? I don't see or get any errors, Ubuntu is just taking too long to boot and to run programs. Please help!

    Read the article

  • Game engine lib and editor

    - by luke
    I would like to know the best way/best practice to handle the following situation. Suppose the project you are working on is split in two sub-projects: game engine lib editor gui. Now, you have a method bool Method( const MethodParams &params ) that will be called during game-level initialization. So it is a method belonging to the game engine lib. Now, the parameters of this method, passed as a reference the structure MethodParams can be decided via the editor, in the level design phase. Suppose the structure is the following: enum Enum1 { E1_VAL1, E1_VAL2, }; enum Enum2 { E2_VAL1, E2_VAL2, E2_VAL3, }; struct MethodParams { float value; Enum1 e1; Enum2 e2; // some other member } The editor should present a dialog that will let the user set the MethodParams struct. A text control for the field value. Furthermore, the editor needs to let the user set the fields e1 and e2 using, for example, two combo boxes (a combo box is a window control that has a list of choices). Obviously, every enum should be mapped to a string, so the user can make an informed selection (i have used E1_VAL1 etc.., but normally the enum would be more meaningful). One could even want to map every enum to a string more informative (E1_VAL1 to "Image union algorithm", E1_VAL2 to "Image intersection algorithm" and so on...). The editor will include all the relevant game egine lib files (.h etc...), but this mapping is not automatic and i am confused on how to handle it in a way that, if in future i add E1_VAL3 and E1_VAL4, the code change will be minimal.

    Read the article

  • Client-server application design issue

    - by user2547823
    I have a collection of clients on server's side. And there are some objects that need to work with that collection - adding and removing clients, sending message to them, updating connection settings and so on. They should perform these actions simultaneously, so mutex or another synchronization primitive is required. I want to share one instance of collection between these objects, but all of them require access to private fields of collection. I hope that code sample makes it more clear[C++]: class Collection { std::vector< Client* > clients; Mutex mLock; ... } class ClientNotifier { void sendMessage() { mLock.lock(); // loop over clients and send message to each of them } } class ConnectionSettingsUpdater { void changeSettings( const std::string& name ) { mLock.lock(); // if client with this name is inside collection, change its settings } } As you can see, all these classes require direct access to Collection's private fields. Can you give me an advice about how to implement such behaviour correctly, i.e. keeping Collection's interface simple without it knowing about its users?

    Read the article

  • Will the Driver Support for Intel HD Graphics be Improved in 12.10?

    - by Hiranya
    I recently installed Ubuntu 12.04 on a HP Pavilion dv4 laptop. This is a core i7 machine with Intel HD graphics and also a separate nVidia VGA card. I had a lot of issues getting Ubuntu 12.04 working on this system. First there were issues booting up the live CD for installation. I worked around that by using the 'nomodeset' option. Then I continued to have similar issues after installation has completed. So I had to permanently add the nomodeset option to my GRUB boot configuration. At the moment I have a working installation but there are many issues: Ubuntu GUI is a bit flaky at times. The mouse pointer goes on and off when hovering over certain icons. Certain things doesn't get rendered properly on the screen. I can't access any of the tty consoles. Hitting Ctrl+Alt+F[1-6] gives me a blank screen. And once that happens I can't even come back to the UI by hitting Ctrl+Alt+F7. I've realized that tty consoles are actually working. I just can't see the text. If I enter a command like 'sudo reboot' into the empty screen the machine reboots. Can't get external displays (monitors, projectors etc) working. But I think this is probably because the VGA out is wired to the nVidia card which is not being used by Linux. colord program crashes every now and then triggering a popup message. So my main question is, will the support for Intel HD graphics be improved in the next release? Or will I have to keep using the nomodeset option in the new release too? Also I appreciate if anybody can shed some light on any of the issues listed above. Thanks in advance.

    Read the article

  • Shader compile log depending on hardware

    - by dreta
    I'm done with the core of my graphics engine and I'm testing it on every platform I can get my hands on. Now, what I noticed is that different drivers return different shader and program compile log content. For example, on my friend's laptop if you successfuly compile a shader then the log is simply empty. However on my PC I get some useful information along with it. So if I compile a vertex shader, I'll get: Vertex shader was successfully compiled to run on hardware. Which isn't that impressive, but is what happens when I compile a program. On my friend's computer the log is empty, since the program compiles. However on my own computer I get: Vertex shader(s) linked, fragment shader(s) linked. Which is awesome, because I'm attaching a geometry shader with 0 (I have a geometry shader file with trash, so it doesn't compile and the pointer is set to 0), and the compiler just tells me which shaders linked. Now it got me thinking, if I was going to buy a graphics card, is there a way for me to get the information about whether or not I'll get this "extended" compile information? Maybe it's vendor specific? Now I don't expect an answer TBH, this seems a bit obscure, but maybe somebody has any experience with this and could post it.

    Read the article

  • Returning a flexible datatype from a C++ function

    - by GavinH
    I'm developing for a legacy C++ application which uses ODBC for it's data access. Coming from a C# background, I really miss the ADO style of data access. I'm writing a wrapper (because we can't actually use ADO) to make our data access less painful. This means no char arrays, no manual text blob streaming, and no declaritive column binding. I'm struggling with how to store / return data values. In C# at least, you can declare an object and cast it to whatever (as long as the type is convertable). My current C++ solution is to use boost::any to store the data value in a custom DataColumnValue object. This class has conversion and assignment operators to the various types used in our app (more than 10). There's a bit of complexity here because if you store an int in the boost::any and try to boost::any_cast<long> you get a boost::bad_any_cast. Client objects shouldn't have to know how the value is stored internally. Does anyone have any experience trying to store / return values whose types are only known at runtime? Is there a better / cleaner way?

    Read the article

< Previous Page | 261 262 263 264 265 266 267 268 269 270 271 272  | Next Page >