Search Results

Search found 14182 results on 568 pages for 'andrew answer'.

Page 496/568 | < Previous Page | 492 493 494 495 496 497 498 499 500 501 502 503  | Next Page >

  • Using std::ifstream to load in an array of struct data type into a std::vector

    - by Sent1nel
    I am working on a bitmap loader in C++ and when moving from the C style array to the std::vector I have run into an usual problem of which Google does not seem to have the answer. 8 Bit and 4 bit, bitmaps contain a colour palette. The colour palette has blue, green, red and reserved components each 1 byte in size. // Colour palette struct BGRQuad { UInt8 blue; UInt8 green; UInt8 red; UInt8 reserved; }; The problem I am having is when I create a vector of the BGRQuad structure I can no longer use the ifstream read function to load data from the file directly into the BGRQuad vector. // This code throws an assert failure! std::vecotr quads; if (coloursUsed) // colour table available { // read in the colours quads.reserve(coloursUsed); inFile.read( reinterpret_cast(&quads[0]), coloursUsed * sizeof(BGRQuad) ); } Does anyone know how to read directly into the vector without having to create a C array and copy data into the BGRQuad vector?

    Read the article

  • If attacker has original data, and encrypted data, can they determine the passphrase?

    - by Brad Cupit
    If an attacker has several distinct items (for example: e-mail addresses) and knows the encrypted value of each item, can the attacker more easily determine the secret passphrase used to encrypt those items? Meaning, can they determine the passphrase without resorting to brute force? This question may sound strange, so let me provide a use-case: User signs up to a site with their e-mail address Server sends that e-mail address a confirmation URL (for example: https://my.app.com/confirmEmailAddress/bill%40yahoo.com) Attacker can guess the confirmation URL and therefore can sign up with someone else's e-mail address, and 'confirm' it without ever having to sign in to that person's e-mail account and see the confirmation URL. This is a problem. Instead of sending the e-mail address plain text in the URL, we'll send it encrypted by a secret passphrase. (I know the attacker could still intercept the e-mail sent by the server, since e-mail are plain text, but bear with me here.) If an attacker then signs up with multiple free e-mail accounts and sees multiple URLs, each with the corresponding encrypted e-mail address, could the attacker more easily determine the passphrase used for encryption? Alternative Solution I could instead send a random number or one-way hash of their e-mail address (plus random salt). This eliminates storing the secret passphrase, but it means I need to store that random number/hash in the database. The original approach above does not require this extra table. I'm leaning towards the the one-way hash + extra table solution, but I still would like to know the answer: does having multiple unencrypted e-mail addresses and their encrypted counterparts make it easier to determine the passphrase used?

    Read the article

  • Give the mount point of a path

    - by Charles Stewart
    The following, very non-robust shell code will give the mount point of $path: (for i in $(df|cut -c 63-99); do case $path in $i*) echo $i;; esac; done) | tail -n 1 Is there a better way to do this? Postscript This script is really awful, but has the redeeming quality that it Works On My Systems. Note that several mount points may be prefixes of $path. Examples On a Linux system: cas@txtproof:~$ path=/sys/block/hda1 cas@txtproof:~$ for i in $(df -a|cut -c 57-99); do case $path in $i*) echo $i;; esac; done| tail -1 /sys On a Mac osx system cas local$ path=/dev/fd/0 cas local$ for i in $(df -a|cut -c 63-99); do case $path in $i*) echo $i;; esac; done| tail -1 /dev Note the need to vary cut's parameters, because of the way df's output differs: indeed, awk is better. Answer It looks like munging tabular output is the only way within the shell, but df /dev/fd/impossible | tail -1 | awk '{ print $NF}' is a big improvement on what I had. Note two differences in semantics: firstly, df $path insists that $path names an existing file, the script I had above doesn't care; secondly, there are no worries about dereferncing symlinks. It's not difficult to write Python code to do the job.

    Read the article

  • jQuery: AJAX call isn't updating page

    - by Cortopasta
    Thought I had a simple AJAX call using $.POST(), but apparently my function isn't firing, and nothing is updating :-/ Here is the call: $(".answerVerse ul li").click(function(){ var rank = $(this).removeClass("star_empty star_full star_highlight").attr("class"); var verse_id = $(this).parent().parent().find(".verseId").html(); var answer_id = $(this).parent().parent().find(".answerId").html(); var place = this; $.post("rank.php", { rank: rank, verse_id: verse_id, answer_id: answer_id },function(data){ $(place).parent().removeClass().addClass(data.newVerseRank); for (i=0;i<=5;i++) { $(".answerVerse ul."+i).each(function(){ $(".answerVerse ul."+i+" li."+i).prevAll().andSelf().removeClass("star_empty").addClass("star_full"); }); } }, "json"); }); And here is the PHP (rank.php) that it calls: require_once("dbcon.php"); $user = new user(); $user->updateVerseRank($_POST['verse_id'], $_POST['rank']); $user->getVerse($_POST['verse_id']); $user->getAnswer($_POST['answer_id']; $arr = array ('newVerseRank'=>htmlspecialchars(round($user->verse[3])),'newVerseVotes'=>htmlspecialchars(round($user->verse[4])),'newAnswerRank'=>htmlspecialchars($user->answer[3])); echo json_encode($arr); Why am I not updating the page? I know it's something dumb I'm doing seeing as how this is my first attempt at AJAX and JSON :-/ Just trying to learn

    Read the article

  • How to catch unintentional function interpositioning?

    - by SiegeX
    Reading through my book Expert C Programming, I came across the chapter on function interpositioning and how it can lead to some serious hard to find bugs if done unintentionally. The example given in the book is the following: my_source.c mktemp() { ... } main() { mktemp(); getwd(); } libc mktemp(){ ... } getwd(){ ...; mktemp(); ... } According to the book, what happens in main() is that mktemp() (a standard C library function) is interposed by the implementation in my_source.c. Although having main() call my implementation of mktemp() is intended behavior, having getwd() (another C library function) also call my implementation of mktemp() is not. Apparently, this example was a real life bug that existed in SunOS 4.0.3's version of lpr. The book goes on to explain the fix was to add the keyword static to the definition of mktemp() in my_source.c; although changing the name altogether should have fixed this problem as well. This chapter leaves me with some unresolved questions that I hope you guys could answer: Does GCC have a way to warn about function interposition? We certainly don't ever intend on this happening and I'd like to know about it if it does. Should our software group adopt the practice of putting the keyword static in front of all functions that we don't want to be exposed? Can interposition happen with functions introduced by static libraries? Thanks for the help. EDIT I should note that my question is not just aimed at interposing over standard C library functions, but also functions contained in other libraries, perhaps 3rd party, perhaps ones created in-house. Essentially, I want to catch any instance of interpositioning regardless of where the interposed function resides.

    Read the article

  • Accessing program information that gdb sees in C++

    - by anon
    I have a program written in C++, on Linux, compiled with -g. When I run it under gdb, I can 1) set breakpoints 2) at those breakpoints, print out variables 3) see the stackframe 4) given a variable that's a structure, print out parts of the structure (i.e. how ddd displays information). Now, given that my program is compiled with "-g" -- is there anyway that I can access this power within my program itself? I.e. given that my program is compiled with "-g", is there some std::vector<string> getStackFrame(); function I can call to get the current stackframe at the current point of execution? Given a pointer to an object and it's type ... can I do std::vector getClassMember(class_name); ? I realize the default answer is "no, C++ doesn't support that level of introspection" -- however, recall I'm on linux, my program is compiled with "-g", and gdb can do it, so clearly the inforamtion is there. Question is: is there some API for accessing it? EDIT: PS Naysers, I'd love to see a reason for closing this question.

    Read the article

  • Are C++ exceptions sufficient to implement thread-local storage?

    - by Potatoswatter
    I was commenting on an answer that thread-local storage is nice and recalled another informative discussion about exceptions where I supposed The only special thing about the execution environment within the throw block is that the exception object is referenced by rethrow. Putting two and two together, wouldn't executing an entire thread inside a function-catch-block of its main function imbue it with thread-local storage? It seems to work fine: #include <iostream> #include <pthread.h> using namespace std; struct thlocal { string name; thlocal( string const &n ) : name(n) {} }; thlocal &get_thread() { try { throw; } catch( thlocal &local ) { return local; } } void print_thread() { cerr << get_thread().name << endl; } void *kid( void *local_v ) try { thlocal &local = * static_cast< thlocal * >( local_v ); throw local; } catch( thlocal & ) { print_thread(); return NULL; } int main() try { thlocal local( "main" ); throw local; } catch( thlocal & ) { print_thread(); pthread_t th; thlocal kid_local( "kid" ); pthread_create( &th, NULL, &kid, &kid_local ); pthread_join( th, NULL ); print_thread(); return 0; } Is this novel or well-characterized? Was my initial premise correct? What kind of overhead does get_thread incur in, say, GCC and VC++? It would require throwing only exceptions derived from struct thlocal, but altogether this doesn't feel like an unproductive insomnia-ridden Sunday morning…

    Read the article

  • OpenGL fast texture drawing with vertex buffer objects. Is this the way to do it?

    - by Matthew Mitchell
    Hello. I am making a 2D game with OpenGL. I would like to speed up my texture drawing by using VBOs. Currently I am using the immediate mode. I am generating my own coordinates when I rotate and scale a texture. I also have the functionality of rounding the corners of a texture, using the polygon primitive to draw those. I was thinking, would it be fastest to make a VBO with vertices for the sides of the texture with no offset included so I can then use glViewport, glScale (Or glTranslate? What is the difference and most suitable here?) and glRotate to move the drawing position for my texture. Then I can use the same VBO with no changes to draw the texture each time. I could only change the VBO when I need to add coordinates for the rounded corners. Is that the best way to do this? What things should I look out for while doing it? Is it really fastest to use GL_TRIANGLES instead of GL_QUADS in modern graphics cards? Thank you for any answer.

    Read the article

  • .Net Inherited Control Property Default

    - by Yisman
    Hello fellows Im trying to make a simple "ButtonPlus" control. the main idea is to inherit from the button control and add some default property values (such as font,color,padding...) No matter how i try, the WinForm always generates (or "serializes") the property value in the client forms the whole point is to have minimal and clean code, not that every instance of the buttonPlus should have 5 lines of init code. I want that the form designer should not generate any code for theses properties and be able to control them from the ButtonPlus code. In other words, if I change the ForeColor from red to blue only 1 single bingle line of code in the app should change. heres my code so far. as you can see, ive tried using defaultvalue, reset , shouldserialize.... anything i was able to find on the web! Public Class ButtonPlus Inherits Button Sub New() 'AutoSize = True AutoSizeMode = Windows.Forms.AutoSizeMode.GrowAndShrink Font = New System.Drawing.Font("Arial", 11.0!, System.Drawing.FontStyle.Bold, System.Drawing.GraphicsUnit.Point, CType(177, Byte)) Padding = New System.Windows.Forms.Padding(3) Anchor = AnchorStyles.Left + AnchorStyles.Right + AnchorStyles.Top ForeColor = Color.Aqua End Sub ' _ 'Public Overrides Property AutoSize() As Boolean ' Get ' Return MyBase.AutoSize ' End Get ' Set(ByVal value As Boolean) ' MyBase.AutoSize = value ' End Set 'End Property Public Function ShouldSerializeAutoSize() As Boolean Return False ' Not AutoSize = True End Function Public Function ShouldSerializeForeColor() As Boolean Return False 'Not ForeColor = Color.Aqua End Function Public Overrides Sub ResetForeColor() ForeColor = Color.Aqua End Sub End Class Thank you very much for taking the time to look this over and answer all the best

    Read the article

  • Modify columns in a data frame in R more cleanly - maybe using with() or apply()?

    - by Mittenchops
    I understand the answer in R to repetitive things is usually "apply()" rather than loop. Is there a better R-design pattern for a nasty bit of code I create frequently? So, pulling tabular data from HTML, I usually need to change the data type, and end up running something like this, to convert the first column to date format (from decimal), and columns 2-4 from character strings with comma thousand separators like "2,400,000" to numeric "2400000." X[,1] <- decYY2YY(as.numeric(X[,1])) X[,2] <- as.numeric(gsub(",", "", X[,2])) X[,3] <- as.numeric(gsub(",", "", X[,3])) X[,4] <- as.numeric(gsub(",", "", X[,4])) I don't like that I have X[,number] repeated on both the left and ride sides here, or that I have basically the same statement repeated for 2-4. Is there a very R-style way of making X[,2] less repetitive but still loop-free? Something that sort of says "apply this to columns 2,3,4---a function that reassigns the current column to a modified version in place?" I don't want to create a whole, repeatable cleaning function, really, just a quick anonymous function that does this with less repetition.

    Read the article

  • Does new JUnit 4.8 @Category render test suites almost obsolete?

    - by grigory
    Given question 'How to run all tests belonging to a certain Category?' and the answer would the following approach be better for test organization? define master test suite that contains all tests (e.g. using ClasspathSuite) design sufficient set of JUnit categories (sufficient means that every desirable collection of sets is identifiable using one or more categories) define targeted test suites based on master test suite and set of categories For example: identify categories for speed (slow, fast), dependencies (mock, database, integration), function (), domain ( demand that each test is properly qualified (tagged) with relevant set of categories. create master test suite using ClasspathSuite (all tests found in classpath) create targeted suites by qualifying master test suite with categories, e.g. mock test suite, fast database test suite, slow integration for domain X test suite, etc. My question is more like soliciting approval rate for such approach vs. classic test suite approach. One unbeatable benefit is that every new test is immediately contained by relevant suites with no suite maintenance. One concern is proper categorization of each test.

    Read the article

  • Use SQL to clone a tree structure represented in a database

    - by AmoebaMan17
    Given a table that represents a hierarchical tree structure and has three columns ID (Primary Key, not-autoincrementing) ParentGroupID SomeValue I know the lowest most node of that branch, and I want to copy that to a new branch with the same number of parents that also need to be cloned. I am trying to write a single SQL INSERT INTO statement that will make a copy of every row that is of the same main has is part one GroupID into a new GroupID. Example beginning table: ID | ParentGroupID | SomeValue ------------------------ 1 | -1 | a 2 | 1 | b 3 | 2 | c Goal after I run a simple INSERT INTO statement: ID | ParentGroupID | SomeValue ------------------------ 1 | -1 | a 2 | 1 | b 3 | 2 | c 4 | -1 | a-cloned 5 | 4 | b-cloned 6 | 5 | c-cloned Final tree structure +--a (1) | +--b (2) | +--c (3) | +--a-cloned (4) | +--b-cloned (5) | +--c-cloned (6) The IDs aren't always nicely spaced out as this demo data is showing, so I can't always assume that the Parent's ID is 1 less than the current ID for rows that have parents. Also, I am trying to do this in T-SQL (for Microsoft SQL Server 2005 and greater). This feels like a classic exercise that should have a pure-SQL answer, but I'm too used to programming that my mind doesn't think in relational SQL.

    Read the article

  • Get the src part of a string [duplicate]

    - by Kay Lakeman
    This question already has an answer here: Grabbing the href attribute of an A element 7 answers First post ever here, and i really hope you can help. I use a database where a large piece of html is stored, now i just need the src part of the image tag. I already found a thread, but i just doesn't do the trick. My code: Original string: <p><img alt=\"\" src=\"http://domain.nl/cms/ckeditor/filemanager/userfiles/background.png\" style=\"width: 80px; height: 160px;\" /></p> How i start: $image = strip_tags($row['information'], '<img>'); echo stripslashes($image); This returns: <img alt="" src="http://domain.nl/cms/ckeditor/filemanager/userfiles/background.png" style="width: 80px; height: 160px;" /> Next step: extract the src part: preg_match('/< *img[^>]*src *= *["\']?([^"\']*)/i', $image, $matches); echo $matches ; This last echo returns: Array What is going wrong? Thanks in advance for your anwser.

    Read the article

  • Inline function v. Macro in C -- What's the Overhead (Memory/Speed)?

    - by Jason R. Mick
    I searched Stack Overflow for the pros/cons of function-like macros v. inline functions. I found the following discussion: Pros and Cons of Different macro function / inline methods in C ...but it didn't answer my primary burning question. Namely, what is the overhead in c of using a macro function (with variables, possibly other function calls) v. an inline function, in terms of memory usage and execution speed? Are there any compiler-dependent differences in overhead? I have both icc and gcc at my disposal. My code snippet I'm modularizing is: double AttractiveTerm = pow(SigmaSquared/RadialDistanceSquared,3); double RepulsiveTerm = AttractiveTerm * AttractiveTerm; EnergyContribution += 4 * Epsilon * (RepulsiveTerm - AttractiveTerm); My reason for turning it into an inline function/macro is so I can drop it into a c file and then conditionally compile other similar, but slightly different functions/macros. e.g.: double AttractiveTerm = pow(SigmaSquared/RadialDistanceSquared,3); double RepulsiveTerm = pow(SigmaSquared/RadialDistanceSquared,9); EnergyContribution += 4 * Epsilon * (RepulsiveTerm - AttractiveTerm); (note the difference in the second line...) This function is a central one to my code and gets called thousands of times per step in my program and my program performs millions of steps. Thus I want to have the LEAST overhead possible, hence why I'm wasting time worrying about the overhead of inlining v. transforming the code into a macro. Based on the prior discussion I already realize other pros/cons (type independence and resulting errors from that) of macros... but what I want to know most, and don't currently know is the PERFORMANCE. I know some of you C veterans will have some great insight for me!!

    Read the article

  • Project Euler, Problem 10 java solution now working

    - by Dennis S
    Hi, I'm trying to find the sum of the prime numbers < 2'000'000. This is my solution in java but I can't seem get the correct answer. Please give some input on what could be wrong and general advice on the code is appreciated. Printing 'sum' gives: 1308111344, which is incorrect. /* The sum of the primes below 10 is 2 + 3 + 5 + 7 = 17. Find the sum of all the primes below two million. */ class Helper{ public void run(){ Integer sum = 0; for(int i = 2; i < 2000000; i++){ if(isPrime(i)) sum += i; } System.out.println(sum); } private boolean isPrime(int nr){ if(nr == 2) return true; else if(nr == 1) return false; if(nr % 2 == 0) return false; for(int i = 3; i < Math.sqrt(nr); i += 2){ if(nr % i == 0) return false; } return true; } } class Problem{ public static void main(String[] args){ Helper p = new Helper(); p.run(); } }

    Read the article

  • What's so bad about building XML with string concatenation?

    - by wsanville
    In the thread What’s your favorite “programmer ignorance” pet peeve?, the following answer appears, with a large amount of upvotes: Programmers who build XML using string concatenation. My question is, why is building XML via string concatenation (such as a StringBuilder in C#) bad? I've done this several times in the past, as it's sometimes the quickest way for me to get from point A to point B when to comes to the data structures/objects I'm working with. So far, I have come up with a few reasons why this isn't the greatest approach, but is there something I'm overlooking? Why should this be avoided? Probably the biggest reason I can think of is you need to escape your strings manually, and most programmers will forget this. It will work great for them when they test it, but then "randomly" their apps will fail when someone throws an & symbol in their input somewhere. Ok, I'll buy this, but it's really easy to prevent the problem (SecurityElement.Escape to name one). When I do this, I usually omit the XML declaration (i.e. <?xml version="1.0"?>). Is this harmful? Performance penalties? If you stick with proper string concatenation (i.e. StringBuilder), is this anything to be concerned about? Presumably, a class like XmlWriter will also need to do a bit of string manipulation... There are more elegant ways of generating XML, such as using XmlSerializer to automatically serialize/deserialize your classes. Ok sure, I agree. C# has a ton of useful classes for this, but sometimes I don't want to make a class for something really quick, like writing out a log file or something. Is this just me being lazy? If I am doing something "real" this is my preferred approach for dealing w/ XML.

    Read the article

  • Random Movement in a Fixed Container

    - by James Barracca
    I'm looking to create something that can move randomly inside of a fixed div container. I love the way the object moves in this example that I found searching this website... http://jsfiddle.net/Xw29r/15/ The code on the jsfiddle contains the following: $(document).ready(function(){ animateDiv(); }); function makeNewPosition(){ // Get viewport dimensions (remove the dimension of the div) var h = $(window).height() - 50; var w = $(window).width() - 50; var nh = Math.floor(Math.random() * h); var nw = Math.floor(Math.random() * w); return [nh,nw]; } function animateDiv(){ var newq = makeNewPosition(); var oldq = $('.a').offset(); var speed = calcSpeed([oldq.top, oldq.left], newq); $('.a').animate({ top: newq[0], left: newq[1] }, speed, function(){ animateDiv(); }); }; function calcSpeed(prev, next) { var x = Math.abs(prev[1] - next[1]); var y = Math.abs(prev[0] - next[0]); var greatest = x > y ? x : y; var speedModifier = 0.1; var speed = Math.ceil(greatest/speedModifier); return speed; }? CSS: div.a { width: 50px; height:50px; background-color:red; position:fixed; }? However, I don't believe the code above constricts that object at all. I need my object to move randomly inside of a container that is let's say for now... 1200px in width and 500px in height. Can someone steer me in the right direction? I'm super new to coding so I'm having a hard time finding an answer on my own. Thanks so much! James

    Read the article

  • java.lang.ClassNotFoundException in Netbeans. 5 hours to fix

    - by user1304281
    Hi I've got to submit an interpreter assignment tonight and all of a sudden it stopped working! It was working yesterday but now when I try to create a class instance at runtime I get classnotfoundexception. My project has no libraries or dependencies, I've written everything myself. I've googled around and it seems to be an issue with classpath but I've had no luck fooling with the project properties on netbeans. Here's some code: package interpreter; import interpreter.bytecode.ByteCode; import java.io.*; import java.lang.reflect.*; class ByteCodeLoader { //.... String codeClass = CodeTable.CodeTable.get(args[0]); ByteCode bytecode = (ByteCode)(Class.forName("interpreter.bytecode."+codeClass).newInstance()); //this throws exception } all of my ByteCodes are contained within a subpackage of interpreter called interpreter.bytecode. I'll be watching this thread so I can answer/clarify any questions immediately. Thanks for your time!

    Read the article

  • Selectively search and replace certain lines using a regular expression

    - by eneveu
    I have a file containing a lot of SQL statements, such as: CREATE TABLE "USER" ( "ID" INTEGER PRIMARY KEY, "NAME" CHARACTER VARYING(50) NOT NULL, "AGE" INTEGER NOT NULL ); COPY "USER" (id, name, age) FROM stdin; 1 Skywalker 19 2 Kenobi 57 I want the column names in the COPY statements to be uppercased and quoted: COPY "USER" ("ID", "NAME", "AGE") FROM stdin; Using sed, I found the following regexp: sed -r 's/([( ])(\w+)([,)])/\1"\U\2\E"\3/g' It does replace the column names, but it is not selective enough, and replaces other words in the file: ~/test]$sed -r 's/([( ])(\w+)([,)])/\1"\U\2\E"\3/g' star_wars_example CREATE TABLE "USER" ( "ID" INTEGER PRIMARY "KEY", "NAME" CHARACTER VARYING("50")NOT "NULL", "AGE" INTEGER NOT NULL ); COPY "USER" ("ID", "NAME", "AGE") FROM stdin; 1 Skywalker 19 2 Kenobi 57 To avoid this problem, I want sed to only apply my regexp to the lines starting with COPY and ending with FROM stdin;. I have looked into lookahead / lookbehind, but they are not supported in sed. They seem to be supported in super-sed, but I am currently using Cygwin (Windows is mandatory here...) and it does not seem available in the package list. Is there a way to force sed to only consider specific line? I've considered piping my file through grep before applying sed, but other lines will then disappear from the output. Am I missing something obvious? It would be great if the answer was easily applicable on a default Cygwin install. I guess I could try installing super-sed on cygwin, but I'd like to know if there are more obvious ideas

    Read the article

  • How can you change the font color of a theme-enabled control?

    - by Edouard Westphal
    Yes, this is again this question: How can I change the font color of a TCheckBox (or any handled control) with Delphi7-Delphi2007 on a themes enabled application? After reading a lot on the internet and on this site, I found 4 kinds of answer: and Most populare (even from QC): You can't, it's designed like that by Microsoft. Create a component that let you draw it like you want. Buy expensive component set that draws like you want. Do not use themes. OK, but I am still unhappy with that. Giving a user colored feedback for the status of a property/data he has on a form, seems legitimate to me. Then I just installed the MSVC# 2008 Express edition, and what a surprise, they can change the color of the font (property ForeColor of the check box) Then what? It does not seem to be a "it's designed like that, by Microsoft." then now the question again: How can I change the font color of a TCheckBox (or any handled control) with Delphi 7 through Delphi 2007 on a theme-enabled application?

    Read the article

  • Which OpenGL functions are not GPU-accelerated?

    - by Xavier Ho
    I was shocked when I read this (from the OpenGL wiki): glTranslate, glRotate, glScale Are these hardware accelerated? No, there are no known GPUs that execute this. The driver computes the matrix on the CPU and uploads it to the GPU. All the other matrix operations are done on the CPU as well : glPushMatrix, glPopMatrix, glLoadIdentity, glFrustum, glOrtho. This is the reason why these functions are considered deprecated in GL 3.0. You should have your own math library, build your own matrix, upload your matrix to the shader. For a very, very long time I thought most of the OpenGL functions use the GPU to do computation. I'm not sure if this is a common misconception, but after a while of thinking, this makes sense. Old OpenGL functions (2.x and older) are really not suitable for real-world applications, due to too many state switches. This makes me realise that, possibly, many OpenGL functions do not use the GPU at all. So, the question is: Which OpenGL function calls don't use the GPU? I believe knowing the answer to the above question would help me become a better programmer with OpenGL. Please do share some of your insights.

    Read the article

  • Get active window title in X

    - by dutt
    I'm trying to get the title of the active window. The application is a background task so if the user has Eclipse open the function returns "Eclipse - blabla", so it's not getting the window title of my own window. I'm developing this in Python 2.6 using PyQt4. My current solution, borrowed and slightly modified from an old answer here at SO, looks like this: def get_active_window_title(): title = '' root_check = '' root = Popen(['xprop', '-root'], stdout=PIPE) if root.stdout != root_check: root_check = root.stdout for i in root.stdout: if '_NET_ACTIVE_WINDOW(WINDOW):' in i: id_ = i.split()[4] id_w = Popen(['xprop', '-id', id_], stdout=PIPE) for j in id_w.stdout: if 'WM_ICON_NAME(STRING)' in j: if title != j.split()[2]: return j.split("= ")[1].strip(' \n\"') It works for most windows, but not all. For example it can't find my kopete chat windows, or the name of the application i'm currently developing. My next try looks like this: def get_active_window_title(self): screen = wnck.screen_get_default() if screen == None: return "Could not get screen" window = screen.get_active_window() if window == None: return "Could not get window" title = window.get_name() return title; But for some reason window is always None. Does somebody have a better way of getting the current window title, or how to modify one of my ways, that works for all windows? Edit: In case anybody is wondering this is the way I found that seems to work for all windows. def get_active_window_title(self): root_check = '' root = Popen(['xprop', '-root'], stdout=PIPE) if root.stdout != root_check: root_check = root.stdout for i in root.stdout: if '_NET_ACTIVE_WINDOW(WINDOW):' in i: id_ = i.split()[4] id_w = Popen(['xprop', '-id', id_], stdout=PIPE) id_w.wait() buff = [] for j in id_w.stdout: buff.append(j) for line in buff: match = re.match("WM_NAME\((?P<type>.+)\) = (?P<name>.+)", line) if match != None: type = match.group("type") if type == "STRING" or type == "COMPOUND_TEXT": return match.group("name") return "Active window not found"

    Read the article

  • Why does my DIV clip its child DIV when jQuery moves it in IE?

    - by Ben Saufley
    I have two divs, both with position:absolute;, one inside the other. The parent isn't in a place where it can be set as position:relative without an extra layer of complexity (there are a lot of other elements around it that I'd have to account for to put it where it needs to be, which is at the very top of the page, over everything). The child element is made to stick off the bottom of the parent. In Chrome, Safari, Firefox, it all works splendidly. In IE, it works until jQuery moves the parent element - at which point the parent element clips the child, so you can barely see the top of the child. I feel like I've read about this, about IE clipping child elements, but I can't seem to find an answer that applies to my case. It's pretty simple, basically: <div id="parent" style="position:absolute;top:0;left:0;"> [content] <div id="tab" style="position:absolute;bottom:-30px;left:0;width:64px;height:32px;background-image:(...);"></div> </div> <script> $(document).ready( function() { $("#tab").click(function() { $("#parent").animate({"top":"-50px"},300); }); }); </script>

    Read the article

  • Move SELECT to SQL Server side

    - by noober
    Hello all, I have an SQLCLR trigger. It contains a large and messy SELECT inside, with parts like: (CASE WHEN EXISTS(SELECT * FROM INSERTED I WHERE I.ID = R.ID) THEN '1' ELSE '0' END) AS IsUpdated -- Is selected row just added? as well as JOINs etc. I like to have the result as a single table with all included. Question 1. Can I move this SELECT to SQL Server side? If yes, how to do this? Saying "move", I mean to create a stored procedure or something else that can be executed before reading dataset in while cycle. The 2 following questions make sense only if answer is "yes". Why do I want to move SELECT? First off, I don't like mixing SQL with C# code. At second, I suppose that server-side queries run faster, since the server have more chances to cache them. Question 2. Am I right? Is it some sort of optimizing? Also, the SELECT contains constant strings, but they are localizable. For instance, WHERE R.Status = "Enabled" "Enabled" should be changed for French, German etc. So, I want to write 2 static methods -- OnCreate and OnDestroy -- then mark them as stored procedures. When registering/unregistering my assembly on server side, just call them respectively. In OnCreate format the SELECT string, replacing {0}, {1}... with required values from the assembly resources. Then I can localize resources only, not every script. Question 3. Is it good idea? Is there an existing attribute to mark methods to be executed by SQL Server automatically after (un)registartion an assembly? Regards,

    Read the article

  • PyGTK: Manually render an existing widget at a given Rectangle? (TextView in a custom CellRenderer)

    - by NicDumZ
    Hello! I am trying to draw a TextView into the cell of a TreeView. (Why? I would like to have custom tags on text, so they can be clickable and trigger different actions/popup menus depending on where user clicks). I have been trying to write a customized CellRenderer for this purpose, but so far I failed because I find it extremely difficult to find generic documentation on rendering design in gtk. More than an answer at the specific question (that might be hard/not doable, and I'm not expecting you to do everything for me), I am first looking for documentation on how a widget is rendered, to understand how one is supposed to implement a CellRenderer. Can you share any link that explains, either for gtk or for pygtk, the rendering mechanism? More specifically: size allocation mechanism (should I say protocol?). I understand that a window has a defined size, and then queries its children, saying "my size is w x h, what would be your ideal size, buddy?", and then sometimes shrinks children when all children cant fit together at their ideal sizes. Any specific documentation on that, and on particular on when this happens during rendering? How are rendered "builtin" widgets? What kind of methods do they call on Widget base class? On the parent Window? When? Do they use pango.Layout? can you manually draw a TextView onto a pango.Layout object? This link gives an interesting example showing how you can draw content in a pango.Layout object and use it in a CellRenderer. I guess that I could adapt it if only I understood how TextView widget are rendered. Or perhaps, to put it more simply: given an existing widget instance, how does one render it at a specific gdk.Rectangle? Thanks a lot.

    Read the article

< Previous Page | 492 493 494 495 496 497 498 499 500 501 502 503  | Next Page >