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  • Background problem on UITableView

    - by f0rz
    Hi ! I have come to a problem, wich I have no idea how to solve. Can anyone think outside the box and point me to right directions? I would be very thankfull ! The problem. I have a UITableView containing a first row wich is always the same (a empty row with repeating background) Next rows are bounch of dynamic data rows. I have set the yellow background on my UITableView in IBuilder, My cells (except first row) have white background with code: UIView* backgroundView = [ [ [ UIView alloc ] initWithFrame:CGRectZero ] autorelease ]; backgroundView.backgroundColor = [UIColor colorWithRed: 0.96078431372549 green: 0.96078431372549 blue: 0.96078431372549 alpha: 1.0]; cell.backgroundView = backgroundView; for ( UIView* view in cell.contentView.subviews ) { view.backgroundColor = [ UIColor clearColor ]; } The example yellow background, I only want to be showed at the top. As u see img example below. The thing is I dont want to have yellow background under the last datarow, I want to contain same white color I have on the cells. This should be white as the cells. Not yellow. Thank u for your time. Regards

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  • iPhone: Use a view as a transparent overlay with closing button

    - by axooh
    I've got a map with three bar buttons for different markers to show up in the map. If I click on a bar button, the specific markers are shown in the map, which already works great. Now I would like to show a transparent overlay (popup window) with the description of the markers after I clicked on a bar button with a button to close the overlay again and show the markers (which are set in the background). The function of the bar button: - (IBAction)routeTwo:(id)sender { // The code for the overlay // ... // remove any annotations that exist [map removeAnnotations:map.annotations]; // Add any annotations which belongs to route 2 [map addAnnotation:[self.mapAnnotations objectAtIndex:2]]; [map addAnnotation:[self.mapAnnotations objectAtIndex:3]]; [map addAnnotation:[self.mapAnnotations objectAtIndex:4]]; [map addAnnotation:[self.mapAnnotations objectAtIndex:5]]; } I tried the following possibilities: 1. Using a modal view controller RouteDescriptionViewController *routeDescriptionView = [[RouteDescriptionViewController alloc] init]; [self presentModalViewController:routeDescriptionView animated:YES]; [routeDescriptionView release]; Works great, but the problem is: The map view in the background is not visible anymore (configuring alpha values of the modal view doesn't change anything). 2. Add RouteDescriptionView as a subview RouteDescriptionViewController *routeDescriptionView = [[RouteDescriptionViewController alloc] init]; [self.view addSubview:routeDescriptionView.view]; [routeDescriptionView release]; Works great as well, but the problem here is: I can't configure a close button on the subview to close/remove the subview (RouteDescriptionView). 3. Using UIAlertView Would work as expected, but the UIAlert is not really customizable and therefore not suitable for my needs. Any ideas how to achieve this?

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  • OpenGL pixels drawn with each horizontal pair swapped

    - by Tim Kane
    I'm somewhat new to OpenGL though I'm fairly sure my problem lies in the pixel format being used, or how my texture is being generated... I'm drawing a texture onto a flat 2D quad using a 16bit RGB5_A1 pixel format, though I don't make use of any alpha at this stage. The problem I'm having is that each pair of horizontal pixel values have been swapped. That is... if the pixels positions should be in this order (assume 8x2 image) 0 1 2 3 4 5 6 7 they are instead drawn as 1 0 3 2 5 4 7 6 Or, more clearly from this image (below). Left is what I get... Right is what I should get. . The question is... How have I ended up with this? Is there something wrong with the pixel format? Unlikely since the colours all appear correct, and I would expect all kinds of nasty if it were down to endian-ness. Suggestions greatly appreciated. Update: Turns out the problem was in my source renderer. Interestingly, I've avoided the problem entirely by using 32-bit textures (haven't tried 24-bit at this point).

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  • Div on top of Div using z-index.

    - by Iacks
    I have the following divs in my HTML: <div class="main"> <div class="bgimage"></div> <div class="content">Text</div> which is directly inside my body. With the following CSS: .content{filter:alpha(opacity=50);-moz-opacity: 0.5;opacity: 0.5;} .content{position:relative;z-index:1;border:#000 thin solid;width:960px;margin-left:auto;margin-right:auto;background-color:#000;} .bgimage{position:absolute;z-index:-1;width:1024px;height:768px;margin-left:auto;margin-right:auto;background-image:url(bg1.jpg);} Basically, I have a Div that with a display of a background image, and I will have another Div on top of this with transparency. This current code works, but my problem is when I am trying to take the content div down from the top. When I add margin-top:100px, for example, is also brings the image down. I thought it would not touch it if it is not on the same z-index? Why does adding a margin also force the bgimage div down? I have also tried making the div with class of content a position of absolute and a zindex, but then this won't centre. How should I solve this?

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  • Is there such a thing as IMAP for podcasts?

    - by Gerrit
    Is there such a thing as IMAP for podcasts? I own a desktop, laptop, iPod, smartphone and a web-client all downloading StackOverflow Podcasts. (among others) They all tell me which episodes are available and which are already played. Everything is a horrible mess, ofcourse. My iPod is somewhat in sync with my desktop, but everything else is a random jungle. The same problem with e-mail is solved by IMAP. Every device gets content and meta-information from one server, and stays in sync with it. Per device, I can set preferences (do or do not download the complete archive including junkmail). Can we implement the IMAP approach for podcasts? Or is there a better metaphore/standard to solve this problem? How will the adoption-strategy look like? (by the way: except for the Windows smartphone, I own a full Apple-stack of products. Even then, I run into this problem) UPDATE The RSS-to-Imap link to sourceforge looks promesting, but very alpha/experimental. UPDATE 2 The one thing RSS is missing is the command/method/parameter/attribute to delete/unread items. RSS can only add, not remove. If RSS(N+1) (3?) could add a value for unread="true|false", it would be solved. If I cache all my RSS-feeds on my own server, and add the attribute myself, I only would have to convince iTunes and every other client to respect that.

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  • Cocoa Touch: Creating and Adding Custom View

    - by Jason
    I create a custom view in cocoa touch that is superclassed by UIView and in my main controller I initialize it and then add it as a subview to the main view, but when I add it to the main view it calls my initializer method again and causes an infinite loop. Am I going about creating my custom view wrong? Here is the mainView (void)loadView { UIImage *tempImage = [UIImage imageNamed: @"image1.jpg"]; CustomImageContainer *testImage = [[CustomImageContainer alloc] initWithImage: tempImage andLabel: @"test image" onTop: true atX: 10 atY: 10]; [self.view addSubview: testImage]; } and the CustomImageContainer -(CustomImageContainer *) initWithImage: (UIImage *)imageToAdd andLabel: (NSString *)text onTop: (BOOL) top atX: (int) x_cord atY: (int) y_cord{ UIImageView *imageview_to_add = [[UIImageView alloc] initWithImage: imageToAdd]; imageview_to_add.frame = CGRectMake(0, 0, imageToAdd.size.width, imageToAdd.size.height); UILabel *label_to_add = [[UILabel alloc] init]; label_to_add.text = text; label_to_add.alpha = 50; label_to_add.backgroundColor = [UIColor blackColor]; label_to_add.textColor = [UIColor whiteColor]; [self addSubview: imageview_to_add]; self.frame = CGRectMake(x_cord, y_cord, imageToAdd.size.width, imageToAdd.size.height); if (top) { label_to_add.frame = CGRectMake(0, 0, imageview_to_add.frame.size.width, imageview_to_add.frame.size.height); //[self addSubview: label_to_add]; } else { label_to_add.frame = CGRectMake(0,.2 * imageview_to_add.frame.size.height, imageview_to_add.frame.size.width, imageview_to_add.frame.size.height); } [self addSubview: label_to_add]; [super init]; return self; }

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  • TFS query mixing Tasks and Bugs, sorted by Priority

    - by Val
    We're using TFS with MSF for Agile 4.2 on a project, and I have a bunch of work to do, both Tasks and Bugs. Both are prioritized by our managers, and assigned due dates and target releases. I use a Work Item query as my main TODO list, and I want to list all the Work Items assigned to me, in order by due date and priority. Problem: I can't seem to find a way to write a unified query that will list both Tasks and Bugs sorted by date and then priority. The problem is that Tasks and Bugs use different fields for Priority. So, my query currently lists the tasks by Due Date, then by Task Priority, then it lists Bugs by Due Date, then by Priority. So, I see tasks that are due later than bugs: Title Due Date Priority Task Priority task1 4/23/2010 Medium task2 4/23/2010 High task3 4/30/2010 Low task4 4/30/2010 Medium bug1 4/23/2010 1 bug2 4/23/2010 2 What I want: Title Due Date Priority Task Priority task1 4/23/2010 Medium task2 4/23/2010 High bug1 4/23/2010 1 bug2 4/23/2010 2 task3 4/30/2010 Low task4 4/30/2010 Medium I don't care if the bugs come before or after the tasks on the same due date; I just want all the work items grouped together by due date, so I never see Tasks for a later due date before Bugs for an earlier one. Another problem is the sorting on Task Priority -- alpha sort means I can't get them to sort by the meaning of the priority. But that's a minor problem I can live with if I can get the Tasks and Bugs intermingled. Any way to do this in a single query?

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  • 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

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  • How to Add Attribute in a XML CDATA? XSLT

    - by iCeR
    Xml: <Frames> <bannerFrame1> <![CDATA[ <iframe src="https://image.domain.com/promobanner1.html" height="320" width="629" scrolling="no" frameborder="0" marginwidth="0" marginheight="0"></iframe> ]]> </bannerFrame1> <bannerFrame2> <![CDATA[ <iframe src="https://image.domain.com/promobanner2.html" height="320" width="629" scrolling="no" frameborder="0" marginwidth="0" marginheight="0"></iframe> ]]> </bannerFrame2> </Frames> XML: bannerFrame1/iframe CDATA source Value may look like something like this <html xmlns="http://www.w3.org/1999/xhtml" lang="en" xml:lang="en"> <body> <div> <img src="banners/banner1.gif" border="0" alt="Banner"/> </div> </body> </html> XSLT: Im getting the CDATA value of the bannerFrame1 <xsl:template match="/"> <xsl:value-of select="Frames/bannerFrame1" disable-output-escaping="yes" /> </xsl:template> Im trying to add a google analytic event tracking code on the image from CDATA "bannerFrame1". How can I add an onclick attribute on <img src="banners/banner1.gif" border="0" alt="Banner"> while getting the CDATA value of <bannerFrame1>? Is it really possible? Thanks in advance. Expected output: <iframe> <html xmlns="http://www.w3.org/1999/xhtml" lang="en" xml:lang="en"> <body> <div> <img src="banners/banner1.gif" border="0" alt="Banner" onclick ="GoogleEventTracker();"/> </div> </body> </html> </iframe> Iframe source: <html xmlns="http://www.w3.org/1999/xhtml" lang="en" xml:lang="en"><head> <meta http-equiv="Content-Type" content="text/html; charset=utf-8"> <meta http-equiv="Pragma" content="no-cache"> <link rel="stylesheet" type="text/css" href="css/style.css"> <link rel="stylesheet" type="text/css" href="css/ui-lightness/jquery-ui-1.7.2.custom.css"> <script type="text/javascript" src="js/jquery-1.3.2.min.js"></script> <script type="text/javascript" src="custombanner/jquery.min.js"> </script> <script type="text/javascript" src="custombanner/jquery.cycle.all.2.74.js"></script> <script type="text/javascript" src="js/jquery-ui-1.7.2.custom.min.js"></script> <!--<script type="text/javascript" src="js/custom.js"></script>--> <title>domain - It's time everyone flies</title> <meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1"> <meta name="script" http-equiv="Content-Script-Type" content="text/javascript"> <meta name="script" http-equiv="Content-Style-Type" content="text/css"> <!--<script type="text/javascript" src="js/soapclient.js"></script>--> <style type="text/css"> img, div, a, input { behavior: url(iepngfix.htc); } #nav { float: left; left: 8px; margin: 15px; position: absolute; top: 235px; padding-left: 242px; /* for 4 frames */ /*padding-left: 278px; /* for 3 frames */ /*padding-left: 312px; /* for 2 frames */ /*padding-left: 242px; /* for 4 frames */ margin-left: 1px; margin-right: 1px; margin-bottom: 1px; height: 40px; /*background :url("banners/gradient.gif") repeat-x scroll 0 0 transparent;*/ } #nav li { display: block; float: left; list-style: none outside none; margin: 2px; padding: 2px; padding-right: 4px; margin-top: 8px; width: 25px; } #nav a { border: 1px solid #ffffff; display: block; padding: 0; width: 25px; } #nav img { border: medium none; display: block; height: 20px; width: 25px; opacity: 0.5; filter: alpha(opacity=50); } #nav li.activeLI { background: #ff0000; } #nav li.activeLI img { opacity: 1; filter: alpha(opacity=100); } </style> </head> <body marginwidth="0" marginheight="0"> <div class="hero"> <div class="slideshow mainpromo" id="slideshow" style="margin-bottom: 50px;"> <!-- <a href="http://www.domain.com/Pages/SeatSalePromo.aspx" target="_top"> <img src="banners/banner1.gif" border="0" alt="Banner" /></a>--> <img src="banners/banner1.gif" border="0" alt="Banner"> </div> <ul id="nav"> </ul> <div class="rightpane"> <!--<a href="http://www.domain.com" target="_top"><img src="banners/promo-fares.jpg" width="206" height="214" border="0" alt="Thumbnail" /></a>--> <img src="banners/lite-fares.jpg" width="206" height="214" border="0" alt="Thumbnail"> <a href="https://book.domain.com/Register.aspx" target="_top"><img src="images/registernow.gif" width="203" height="20" border="0" alt="See all Low Fares"></a> <!--<center><a href="http://www.domain.com/Pages/WebCheck-in.aspx" target="_top"><font size="2" color="#ff6600">Web Check-In</font></a></center>--> <!--<a href="http://domain.com" target="_blank"><img src="images/topdestinatios_btn.gif" alt="" width="149" height="26" border="0" /></a>--> </div> <div id="alerts"> <p> <strong>Seat Sale Alert! </strong>Be the first to know thePromos. <a target="_top" href="http://www.domain.com/pages/emms-signup.aspx">SUBSCRIBE NOW »</a> </p> <p> <!-- <strong>Seat Sale Availability</strong> Find the best time to travel. <a target="_top" href="http://www.domain.com/documents/seat_map.pdf">DOWNLOAD PDF &raquo;</a>--> </p> <div class="clear"> </div> </div> <div style="clear: both;"> </div> <div id="mascot"> <img src="images/mascot.png" alt=""> </div> <div style="clear: both;"> </div> </div> </body></html>

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  • VB6 Game Development

    - by CVS-2600Hertz-wordpress-com
    Hi All, I am developing a game in VB6 (plz don't ask me why :) ). The storyboard is ready and a rough implementation is underway. I am following a "pure-software-rendering" approach. (i.e. no DirectX, no openGL etc.) Amongst many others, the following "serious" problems exist: 2D alpha transparency reqd. to implement overlays. Parallax implementation to give depth-of-field illusion. Capturing mouse-scroll events globally (as in FPS-es; mapping them to changing weapon). Async sound play with absolute "near-zero-lag". Any ideas anyone. Please suggest any well documented library/ocx or sample-code. Plz do suggest solutions with good performance and as little overhead as possible. Also, anyone who has developed any games, and would be open to sharing her/his code would be highly appreciated. (any well-acknowledged VB games whose source-code i can study??) UPDATE: Here is a screen shot of GearHead Garage. This picture ought to describe what i was attempting in words above... :) Thank You

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  • Loading an FLV in Facebox with jQuery for IE7 and IE8

    - by Trip
    It goes almost without saying, this works perfectly in Chrome, Firefox, and Safari. IE (any version) being the problem. Objective: I am trying to load JWplayer which loads an FLV from S3 in a Facebox popup. jQuery(document).ready(function($) { $('a[rel*=facebox]').facebox() }) HTML (haml): %li#videoGirl = link_to 'What is HQchannel?', '#player', :rel => 'facebox' .grid_8.omega.alpha#player{:style => 'display: none;'} :javascript var so = new SWFObject('/flash/playerTrans.swf','mpl','640px','360px','0'); so.addParam('allowscriptaccess','always'); so.addParam('allowfullscreen','true'); so.addParam('wmode','transparent'); so.addVariable('file', 'http://hometownquarterlyvideos.s3.amazonaws.com/whatishqchannel.flv&autostart=true&controlbar=none&repeat=always&image=/flash/video_girl/whatishqchannel.jpg&icons=false&screencolor=none&backcolor=FFFFFF&screenalpha=0&overstretch'); so.addVariable('overstretch', 'true') so.write('player'); Problem: Despite the video being set to display: none;. It begins playing anyway. When clicking on the activation div, IE7 pops up a wrong sized blank div with a nav (params are set to not show nav and scrubber), and no buttons on the nav and srubber work. IE8 shows the right size but same behavior with nav and scrubber not working, and blank screen. My guess: I'm thinking that the problem is with the javascript not being called at the right times. It seems it's loading the facebox without the jwplayer. At least I assume. Hence the reason why the nav is there. I thinking that it did not read the javascript for that.

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  • AS3 trouble instantiating Document Class of loaded SWF

    - by Marcy Sutton
    I am loading one swf into another using the Loader class, but when the child swf finishes loading and is added to the display list, its Document Class is not instantiated. I have a few trace statements should execute when the object is created. When I compile the child SWF on its own, the Document Class runs as expected. So I'm wondering... how do I associate a child SWF's Document Class with Loader.content? // code in parent SWF's Document Class (Preloader) public function Preloader(){ swfLoader = new Loader(); swfLoader.contentLoaderInfo.addEventListener(Event.COMPLETE, loaderDone); swfLoader.load(new URLRequest("mainmovie.swf")); } private function loaderDone(e:Event):void { // Add Loader.content to new Sprite mainMovie = Sprite(e.target.content); mainMovie.alpha = 0; swfLoader = null; addChildAt(mainMovie, 0); mainMovie.addEventListener(Event.ADDED_TO_STAGE, mainMovieAddedListener); } // functions in MainMovie.as not ever running, // even though it is listed as the child SWF's Document Class Cheers!

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  • iPhone OpenGL ES Texture2D Masking

    - by Robert Neagu
    What's the best choice when trying to mask a texture like ColorSplash or other apps like iSteam, etc? I started learning OPENGL ES like... 4 days ago (I'm a total rookie) and tried the following approach: 1) I created a colored texture2D, a grayscale version of the first texture and a third texture2D called mask 2) I also created a texture2D for the brush... which is grayscale and it's opaque (brush = black = 0,0,0,1 and surroundings = white = 1,1,1,1). My intention was to create an antialiased brush with smooth edges but i'm fine with a normal one right now 3) I searched for masking techniques on the internet and found this tutorial ZeusCMD - Design and Development Tutorials : OpenGL ES Programming Tutorials - Masking about masking. The tutorial tells me to use blending to achieve masking... first draw colored, then mask with glBlendFunc(GL_DST_COLOR, GL_ZERO) and then grayscale with glBlendFunc(GL_ONE, GL_ONE) ... and this gives me something close to what i want... but not exactly what i want. The result is masked but it's somehow overbright-ed 4) For drawing to the mask texture i used an extra frame buffer object (FBO) I'm not really happy with the resulting image (overbright-ed picture) nor with the speed achieved with this method. I think the normal way was to draw directly to the grayscale (overlay) texture2D affecting only it's alpha channel in the places where the brush hits. Is there a fast way to achieve this? I have searched a lot and never got an answer that's clear and understandable. Then, in the main draw loop I could only draw the colored texture and then blend the grayscale ontop with glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA). I just want to learn to use OPENGL ES and it's driving me nuts because i can't get it to work properly. An advice, a link to a tutorial would be much appreciated.

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  • Error in Ordinary Differential Equation representation

    - by Priya M
    UPDATE I am trying to find the Lyapunov Exponents given in link LE. I am trying to figure it out and understand it by taking the following eqs for my case. These are a set of ordinary differential equations (these are just for testing how to work with cos and sin as ODE) f(1)=ALPHA*(y-x); f(2)=x*(R-z)-y; f(3) = 10*cos(x); and x=X(1); y=X(2); cos(y)=X(3); f1 means dx/dt;f2 dy/dt and f3 in this case would be -10sinx. However,when expressing as x=X(1);y=X(2);i am unsure how to express for cos.This is just a trial example i was doing so as to know how to work with equations where we have a cos,sin etc terms as a function of another variable. When using ode45 to solve these Eqs [T,Res]=sol(3,@test_eq,@ode45,0,0.01,20,[7 2 100 ],10); it throws the following error ??? Attempted to access (2); index must be a positive integer or logical. Error in ==> Eq at 19 x=X(1); y=X(2); cos(x)=X(3); Is my representation x=X(1); y=X(2); cos(y)=X(3); alright? How to resolve the error? Thank you

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  • How to get the second sub element of every element in a list in R

    - by PaulHurleyuk
    I know I've come across this problem before, but I'm having a bit of a mental block at the moment. and as I can't find it on SO, I'll post it here so I can find it next time. I have a dataframe that contains a field representing an ID label. This label has two parts, an alpha prefix and a numeric suffix. I want to split it apart and create two new fields with these values in. structure(list(lab = c("N00", "N01", "N02", "B00", "B01", "B02", "Z21", "BA01", "NA03")), .Names = "lab", row.names = c(NA, -9L ), class = "data.frame") df$pre<-strsplit(df$lab, "[0-9]+") df$suf<-strsplit(df$lab, "[A-Z]+") Which gives lab pre suf 1 N00 N , 00 2 N01 N , 01 3 N02 N , 02 4 B00 B , 00 5 B01 B , 01 6 B02 B , 02 7 Z21 Z , 21 8 BA01 BA , 01 9 NA03 NA , 03 So, the first strsplit works fine, but the second gives a list, each having two elements, an empty string and the result I want, and stuffs them both into the dataframe column. How can I select the second sub-element from each element of the list ? (or, is there a better way to do this) Thanks Paul.

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  • Paragraph with normal opacity within greyed-out div

    - by dmr
    I am greying out a web page when a user doesn't have permission to access it. In order to do that, I am placing a div with background-color white and a lowered opacity on top of the web page. I want to write some words in that div with the words having a normal opacity. As of now, the greyed out background is showing correctly. However, I can't seem to get the words to be a regular opacity. The derived styles on Firebug show the opacity on the words as normal, but it clearly isn't. What am I doing wrong? The HTML: <div class="noPermission"> <p>I'm sorry. You do not have permission to access this page.</p> </div> The CSS: div.noPermission { background-color: white; filter:alpha(opacity=50); /* IE */ opacity: 0.5; /* Safari, Opera */ -moz-opacity:0.50; /* FireFox */ z-index: 20; height: 100%; width: 100%; background-repeat:no-repeat; background-position:center; position:absolute; top: 0px; left: 0px; } div.noPermission p{ color: black; margin: 300px auto auto 50px; text-align: left; font-weight: bold; font-size: 18px; display: block; width: 250px; }

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  • OpenGLES - Rendering a background image only once and not wiping it

    - by chaosbeaker
    Hello, first time asking a question here but been watching others answers for a while. My own question is one for improving the performance of my program. Currently I'm wiping the viewFrameBuffer on each pass through my program and then rendering the background image first followed by the rest of my scene. I was wondering how I go about rendering the background image once, and only wiping the rest of the scene for updating/re-rendering. I tried using a seperate buffer but I'm not sure how to present this new buffer to the render buffer. // Set the current EAGLContext and bind to the framebuffer. This will direct all OGL commands to the // framebuffer and the associated renderbuffer attachment which is where our scene will be rendered [EAGLContext setCurrentContext:context]; glBindFramebufferOES(GL_FRAMEBUFFER_OES, viewFramebuffer); // Define the viewport. Changing the settings for the viewport can allow you to scale the viewport // as well as the dimensions etc and so I'm setting it for each frame in case we want to change i glViewport(0, 0, screenBounds.size.width , screenBounds.size.height); // Clear the screen. If we are going to draw a background image then this clear is not necessary // as drawing the background image will destroy the previous image glClearColor(0.0f, 1.0f, 0.0f, 1.0f); glClear(GL_COLOR_BUFFER_BIT); // Setup how the images are to be blended when rendered. This could be changed at different points during your // render process if you wanted to apply different effects glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA); switch (currentViewInt) { case 1: { [background render:CGPointMake(240, 0) fromTopLeftBottomRightCenter:@"Bottom"]; // Other Rendering Code }} // Bind to the renderbuffer and then present this image to the current context glBindRenderbufferOES(GL_RENDERBUFFER_OES, viewRenderbuffer); [context presentRenderbuffer:GL_RENDERBUFFER_OES]; Hopefully by solving this I'll also be able to implement another buffer just for rendering particles as I can set them to always use a black background as their alpha source. Any help is greatly appreciated

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  • Auto increment with a Unit Of Work

    - by Derick
    Context I'm building a persistence layer to abstract different types of databases that I'll be needing. On the relational part I have mySQL, Oracle and PostgreSQL. Let's take the following simplified MySQL tables: CREATE TABLE Contact ( ID varchar(15), NAME varchar(30) ); CREATE TABLE Address ( ID varchar(15), CONTACT_ID varchar(15), NAME varchar(50) ); I use code to generate system specific alpha numeric unique ID's fitting 15 chars in this case. Thus, if I insert a Contact record with it's Addresses I have my generated Contact.ID and Address.CONTACT_IDs before committing. I've created a Unit of Work (amongst others) as per Martin Fowler's patterns to add transaction support. I'm using a key based Identity Map in the UoW to track the changed records in memory. It works like a charm for the scenario above, all pretty standard stuff so far. The question scenario comes in when I have a database that is not under my control and the ID fields are auto-increment (or in Oracle sequences). In this case I do not have the db generated Contact.ID beforehand, so when I create my Address I do not have a value for Address.CONTACT_ID. The transaction has not been started on the DB session since all is kept in the Identity Map in memory. Question: What is a good approach to address this? (Avoiding unnecessary db round trips) Some ideas: Retrieve the last ID: I can do a call to the database to retrieve the last Id like: SELECT Auto_increment FROM information_schema.tables WHERE table_name='Contact'; But this is MySQL specific and probably something similar can be done for the other databases. If do this then would need to do the 1st insert, get the ID and then update the children (Address.CONTACT_IDs) – all in the current transaction context.

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  • TicTacToe strategic reduction

    - by NickLarsen
    I decided to write a small program that solves TicTacToe in order to try out the effect of some pruning techniques on a trivial game. The full game tree using minimax to solve it only ends up with 549,946 possible games. With alpha-beta pruning, the number of states required to evaluate was reduced to 18,297. Then I applied a transposition table that brings the number down to 2,592. Now I want to see how low that number can go. The next enhancement I want to apply is a strategic reduction. The basic idea is to combine states that have equivalent strategic value. For instance, on the first move, if X plays first, there is nothing strategically different (assuming your opponent plays optimally) about choosing one corner instead of another. In the same situation, the same is true of the center of the walls of the board, and the center is also significant. By reducing to significant states only, you end up with only 3 states for evaluation on the first move instead of 9. This technique should be very useful since it prunes states near the top of the game tree. This idea came from the GameShrink method created by a group at CMU, only I am trying to avoid writing the general form, and just doing what is needed to apply the technique to TicTacToe. In order to achieve this, I modified my hash function (for the transposition table) to enumerate all strategically equivalent positions (using rotation and flipping functions), and to only return the lowest of the values for each board. Unfortunately now my program thinks X can force a win in 5 moves from an empty board when going first. After a long debugging session, it became apparent to me the program was always returning the move for the lowest strategically significant move (I store the last move in the transposition table as part of my state). Is there a better way I can go about adding this feature, or a simple method for determining the correct move applicable to the current situation with what I have already done?

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  • How can I correctly calculate the direction for a moving object?

    - by Jakub Hampl
    I'm solving the following problem: I have an object and I know its position now and its position 300ms ago. I assume the object is moving. I have a point to which I want the object to get. What I need is to get the angle from my current object to the destination point in such a format that I know whether to turn left or right. The idea is to assume the current angle from the last known position and the current position. I'm trying to solve this in MATLAB. I've tried using several variations with atan2 but either I get the wrong angle in some situations (like when my object is going in circles) or I get the wrong angle in all situations. Examples of code that screws up: a = new - old; b = dest - new; alpha = atan2(a(2) - b(2), a(1) - b(1); where new is the current position (eg. x = 40; y = 60; new = [x y];), old is the 300ms old position and dest is the destination point. Edit Here's a picture to demonstrate the problem with a few examples: In the above image there are a few points plotted and annotated. The black line indicates our estimated current facing of the object. If the destination point is dest1 I would expect an angle of about 88°. If the destination point is dest2 I would expect an angle of about 110°. If the destination point is dest3 I would expect an angle of about -80°.

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  • R plotting multiple histograms on single plot to .pdf as a part of R batch script

    - by Bryce Thomas
    I am writing R scripts which play just a small role in a chain of commands I am executing from a terminal. Basically, I do much of my data manipulation in a Python script and then pipe the output to my R script for plotting. So, from the terminal I execute commands which look something like $python whatever.py | R CMD BATCH do_some_plotting.R. This workflow has been working well for me so far, though I have now reached a point where I want to overlay multiple histograms on the same plot, inspired by this answer to another user's question on Stackoverflow. Inside my R script, my plotting code looks like this: pdf("my_output.pdf") plot(hist(d$original,breaks="FD",prob=TRUE), col=rgb(0,0,1,1/4),xlim=c(0,4000),main="original - This plot is in beta") plot(hist(d$minus_thirty_minutes,breaks="FD",prob=TRUE), col=rgb(1,0,0,1/4),add=T,xlim=c(0,4000),main="minus_thirty_minutes - This plot is in beta") Notably, I am using add=T, which is presumably meant to specify that the second plot should be overlaid on top of the first. When my script has finished, the result I am getting is not two histograms overlaid on top of each other, but rather a 3-page PDF whose 3 individual plots contain the titles: i) Histogram of d$original ii) original - This plot is in beta iii) Histogram of d$minus_thirty_minutes So there's two points here I'm looking to clarify. Firstly, even if the plots weren't overlaid, I would expect just a 2-page PDF, not a 3-page PDF. Can someone explain why I am getting a 3-page PDF? Secondly, is there a correction I can make here somewhere to get just the two histograms plotted, and both of them on the same plot (i.e. 1-page PDF)? The other Stackoverflow question/answer I linked to in the first paragraph did mention that alpha-blending isn't supported on all devices, and so I'm curious whether this has anything to do with it. Either way, it would be good to know if there is a R-based solution to my problem or whether I'm going to have to pipe my data into a different language/plotting engine.

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  • ImageViews sometimes not displaying in FrameLayout activity

    - by Ken
    The top level layout in my activity is a framelayout. I have completed, debugged and tested this app and it works exactly like it should in all respects on my g1 and on various emulators. But on 3.7-inch displays running 2.1+, some imageviews packed in a linearlayout are periodically not visible. I know that they are there because you can touch and drag them with effect in the app. So I assume somehow they have gotten under the SurfaceView that is the main component of the app. This is apparently so even though the SurfaceView is declared in the xml prior to the LinearLayout. However, the ImageViews IN the LinearLayout are added programmatically towards the end of onCreate(). Framelayout stacks everything that is added to it, one on top of the other--the only way you will see more than one child of a frame layout is if they are smaller than the screen and are placed apart from eachother. Oddly, sometimes the imageviews ARE visible--it is random. Anyway, I've been trying to combat this with framelayout.bringChildToFront(View v) on the linearlayout without success. I wonder if anyone has any insight into how the behavior could be random like that, and how I should code these imageviews to keep this from happening, and why the problem appears only to occur on 3.7 vs 3.2 inch screens (as it happens, the two 3.2-inch screens were both htc, so vendor might be factor too). [edit] Actually, I've determined that this is a 2.2 issue, not a screen size (or even vendor) issue. Can't ensure that ImageViews added to a framelayout with a SurfaceView in it will appear on top of the surfaceview. I ran some tests in the respective onDraw() methods and the imageviews are 'visible' (0), and nothing does anything to the alpha of the drawables, which are there as well at ondraw(). [/edit] Any insight would be welcomed. Ken T.

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  • Why is "origin/HEAD" shown when running "git branch -r"?

    - by Ben Hamill
    When you run git branch -r why the blazes does it list origin/HEAD? For example, there's a remote repo on GitHub, say, with two branches: master and awesome-feature. If I do git clone to grab it and then go into my new directory and list the branches, I see this: $ git branch -r origin/HEAD origin/master origin/awesome-feature Or whatever order it would be in (alpha? I'm faking this example to keep the identity of an innocent repo secret). So what's the HEAD business? Is it what the last person to push had their HEAD pointed at when they pushed? Won't that always be whatever it was they pushed? HEADs move around... why do I care what someone's HEAD pointed at on another machine? I'm just getting a handle on remote tracking and such, so this is one lingering confusion. Thanks! EDIT: I was under the impression that dedicated remote repos (like GitHub where no one will ssh in and work on that code, but only pull or push, etc) didn't and shouldn't have a HEAD because there was, basically, no working copy. Not so?

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  • In Powerpoint 2007, how can I position a Callout's Tail programatically?

    - by Rorschach
    I'm looking at the XML and this is what it has for the Callout object's coordinates and geometry: <p:spPr> <a:xfrm> <a:off x="2819400" y="5181600"/> // X,Y Position of Callout Box <a:ext cx="609600" cy="457200"/> // Width,Height of Callout Box </a:xfrm> <a:prstGeom prst="wedgeRectCallout"> <a:avLst> <a:gd name="adj1" fmla="val 257853"/> // X Position Of Tail <a:gd name="adj2" fmla="val -532360"/> // Y Position of Tail </a:avLst> </a:prstGeom> <a:solidFill> <a:schemeClr val="accent1"> <a:alpha val="50000"/> </a:schemeClr> </a:solidFill> </p:spPr> What I'm having trouble with is the formula for telling it to place the tail at a particular coordinate on the slide. I've tried this to calculate it, but it does not work correctly. //This gives me the distance between the Coordinate and the Center of the Callout. DistanceX = Coordinate.X - (Callout.X + Callout.X_Ext)/2 DistanceY = Coordinate.Y - (Callout.Y + Callout.Y_Ext)/2 But, the geometric value is not the distance between the two points. Anybody know what the formula is for calculating this?

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  • gl_FragColor and glReadPixels

    - by chun0216
    I am still trying to read pixels from fragment shader and I have some questions. I know that gl_FragColor returns with vec4 meaning RGBA, 4 channels. After that, I am using glReadPixels to read FBO and write it in data GLubyte *pixels = new GLubyte[640*480*4]; glReadPixels(0, 0, 640,480, GL_RGBA, GL_UNSIGNED_BYTE, pixels); This works fine but it really has speed issue. Instead of this, I want to just read RGB so ignore alpha channels. I tried: GLubyte *pixels = new GLubyte[640*480*3]; glReadPixels(0, 0, 640,480, GL_RGB, GL_UNSIGNED_BYTE, pixels); instead and this didn't work though. I guess it's because gl_FragColor returns 4 channels and maybe I should do something before this? Actually, since my returned image (gl_FragColor) is grayscale, I did something like float gray = 0.5 //or some other values gl_FragColor = vec4(gray,gray,gray,1.0); So is there any efficient way to use glReadPixels instead of using the first 4 channels method? Any suggestion? By the way, this is on opengl es 2.0 code.

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