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  • Can this navigation be done completely in CSS [migrated]

    - by atrljoe
    I am a little stuck. I have created almost everything in the picture below. What I am stuck on is I am trying to figure out how I would set it up so that when a user clicks one of the links it makes the line below become red (after the next page loads). Obviously I would need to use Jquery to detect the page then add inline css, but what I am struggling with is I want this to be as easy as possible so that I can give this template to others and then they can add or remove items as necessary. I was trying to figure out if I could somehow use a li element to do this but I have not found a way yet. Does anyone have any ideas to help me?

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  • Exposing warnings\errors from data objects (that are also list returned)

    - by Oren Schwartz
    I'm exposing Data objects via service oriented assembly (which on future usages might become a WCF service). The data object is tree designed, as well as formed from allot of properties.Moreover, some services return one objects, others retrieve a list of them (thus disables throwing exceptions). I now want to expose data flow warnings and wondering what's the best way to do it having to things to consider: (1) seperation (2) ease of access. On the one hand, i want the UI team to be able to access a fields warnings (or errors) without having them mapping the field names to an external source but on the other hand, i don't want the warnings "hanged" on the object itself (as i don't see it a correct design). I tought of creating a new type of wrapper for each field, that'll expose events and they'll have to register the one's they care about (but totally not sure) I'll be happy to hear your thoughts. Could you please direct me to a respectful design pattern ? what dp will do best here ? Thank you very much!

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  • How do I export customized Libreoffice config files?

    - by carestad
    Is this possible? I want to make my own config file for my customizations that I can apply whenever I reinstall my system. For example, Ubuntu's default font color is just stupid. I want it to be BLACK and not dark grey. And I want to turn on autosave every 3rd minute and backup files. Is there a config file that I can change? The .libreoffice/* folders and XML files doesn't make sense, and they don't seem to change when I change stuff in LibreOffice. Could someone please help me out with this? Thanks.

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  • Please help ubuntu or any other linux os is not booting from cd or usb

    - by Amith
    I will tell you the whole story,one night when i was using KDE on Ubuntu 10.10 Kwin crashed then i shut down the os next day when i booted it the display came completely garbled and i went to safe graphics mode ,it worked and in reinstalled the Nvidia drivers and then restarted .Then immediatly, It said No init found Busybox XX.XX then I thought ill do a fresh install I inserted the ubuntu cd provided to me by Canonical.When i pressed 'try ubuntu without installing' instead of the graphic boot screen i saw.Ubuntu 10.10 in regular text and a progress bar few seconds after that the screen was flooded with error messages first alot of white then red.I then went to my win7 installation and saw a website which told me to find a Ext3 reader and format the ubuntu partition and the swap.I did that and when i restarted. GRUB configuration not found grub> Then it took my win 7 ERD and restored 7's bootloder Xp and 7 were working i put in the livecd again,Same error,Now usin my seven,Please help geeks,Ive even tried Knoppix,Fedora,Debiane.t.c they wont boot and i want to retain my win 7 and winxp partitions,I really miss linux.

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  • For Programmers familiar with ACM API? Drawing Initials [closed]

    - by user71992
    Possible Duplicate: For Programmers familiar with ACM API? Drawing Initials I came across an exercise (in the book "The Art and Science of Java" by Eric Roberts) that requires using only GArc and GLine classes to create a lettering library which draws your initials on the canvas. This should be made independent of the GLabel class. I'd like to know the correct approach to use in solving this problem. I'm not sure what I have so far is good enough (I'm thinking it's too long). The questions requires that I use a good Top-Down approach. Here's my code so far: //Passes letters to GLetter objects and draws them on the canvas package artScienceJavaExercises.chapter8; import acm.program.*; //import acm.graphics.*; public class DrawInitials extends GraphicsProgram{ public void init(){ resize(400,400); } public void run(){ //String let = readLine("Letter?: "); letter = new GLetter("l"); add(letter, (getWidth()-letter.getWidth()*2)/2, (getHeight()-letter.getHeight())/2); add(new GLetter("o"), (letter.getX()+letter.getWidth()), letter.getY()); } private GLetter letter; } //GLetter Class package artScienceJavaExercises.chapter8; import acm.graphics.*; import java.awt.*; public class GLetter extends GCompound{ private static final int ONE_THIRD = 30; private static final int ROW_2_HEIGHT = 40; private GArc[] arc = new GArc[4]; private GLine[] line = new GLine[24]; public GLetter(String s){ line[0] = new GLine(0,0, ONE_THIRD, 0); line[1] = new GLine(ONE_THIRD,0, ONE_THIRD*2, 0); line[2] = new GLine(ONE_THIRD*2,0, ONE_THIRD*3, 0); line[3] = new GLine(0,0, 0,ONE_THIRD); line[4] = new GLine(ONE_THIRD,0, ONE_THIRD, ONE_THIRD); line[5] = new GLine(ONE_THIRD*2,0, ONE_THIRD*2, ONE_THIRD); line[6] = new GLine(ONE_THIRD*3,0, ONE_THIRD*3, ONE_THIRD); line[7] = new GLine(0,ONE_THIRD, ONE_THIRD*2, ONE_THIRD); line[8] = new GLine(ONE_THIRD,ONE_THIRD, ONE_THIRD*2, ONE_THIRD); line[9] = new GLine(ONE_THIRD*2,ONE_THIRD, ONE_THIRD*3, ONE_THIRD); line[10] = new GLine(0,ONE_THIRD, 0, ONE_THIRD+ROW_2_HEIGHT); line[11] = new GLine(ONE_THIRD, ONE_THIRD, ONE_THIRD, ONE_THIRD+ROW_2_HEIGHT); line[12] = new GLine(ONE_THIRD*2,ONE_THIRD, ONE_THIRD*2, ONE_THIRD+ROW_2_HEIGHT); line[13] = new GLine(ONE_THIRD*3,ONE_THIRD, ONE_THIRD*3, ONE_THIRD+ROW_2_HEIGHT); line[14] = new GLine(0, ONE_THIRD+ROW_2_HEIGHT, ONE_THIRD, ONE_THIRD+ROW_2_HEIGHT); line[15] = new GLine(ONE_THIRD, ONE_THIRD+ROW_2_HEIGHT, ONE_THIRD*2, ONE_THIRD+ROW_2_HEIGHT); line[16] = new GLine(ONE_THIRD*2, ONE_THIRD+ROW_2_HEIGHT, ONE_THIRD*3, ONE_THIRD+ROW_2_HEIGHT); line[17] = new GLine(0, ONE_THIRD+ROW_2_HEIGHT, 0, ONE_THIRD*2+ROW_2_HEIGHT); line[18] = new GLine(ONE_THIRD, ONE_THIRD+ROW_2_HEIGHT, ONE_THIRD, ONE_THIRD*2+ROW_2_HEIGHT); line[19] = new GLine(ONE_THIRD*2, ONE_THIRD+ROW_2_HEIGHT, ONE_THIRD*2, ONE_THIRD*2+ROW_2_HEIGHT); line[20] = new GLine(ONE_THIRD*3, ONE_THIRD+ROW_2_HEIGHT, ONE_THIRD*3, ONE_THIRD*2+ROW_2_HEIGHT); line[21] = new GLine(0,ONE_THIRD*2+ROW_2_HEIGHT, ONE_THIRD, ONE_THIRD*2+ROW_2_HEIGHT); line[22] = new GLine(ONE_THIRD, ONE_THIRD*2+ROW_2_HEIGHT, ONE_THIRD*2, ONE_THIRD*2+ROW_2_HEIGHT); line[23] = new GLine(ONE_THIRD*2,ONE_THIRD*2+ROW_2_HEIGHT, ONE_THIRD*3, ONE_THIRD*2+ROW_2_HEIGHT); for(int i = 0; i<line.length; i++){ add(line[i]); line[i].setColor(Color.BLACK); line[i].setVisible(false); } arc[0] = new GArc(getWidth(), getHeight(), 106.699, 49.341); arc[1] = new GArc(getWidth(), getHeight(), 23.96, 49.341); arc[2] = new GArc(getWidth(), getHeight(), -23.96, -49.341); arc[3] = new GArc(0,0,getWidth(), getHeight(), -106.699, -49.341); for(int i = 0; i<arc.length; i++){ add(arc[i],0,0); arc[i].setColor(Color.BLACK); arc[i].setVisible(false); } paintLetter(s); } private void paintLetter(String s){ if (s.equalsIgnoreCase("l")){ turnOn(line[3]); turnOn(line[10]); turnOn(line[17]); turnOn(line[21]); turnOn(line[22]); turnOn(line[23]); } else if(s.equalsIgnoreCase("o")){ for(int i = 0; i<4; ++i){ turnOn(arc[i]); } turnOn(line[1]); turnOn(line[10]); turnOn(line[13]); turnOn(line[22]); } } private void turnOn(GObject g){ g.setVisible(true); } } I created a class (GLetter.java) with arrays for GArc and GLine objects. They are positioned in certain ways thereby turning certain Glines and/or GArcs on or off (changing visiblity) would create a pattern for a letter. This Gletter uses the if/else statements to determine which pattern to create - this makes me feel my code is too long. There is another class (DrawInitials.java) that simulates a GraphicsProgram and allows the user to pass certain letters as arguments to the GLetter object. I've used 'L' and 'O' as examples. However, I posted this because I'm not sure I'm using the right approach. That's why I need your help. I feel MY CODE IS TOO LONG! The code above is not the complete project...it only draws letters 'L' and 'O' for now.

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  • Bitmap to Texture2D problem with colors

    - by xnaNewbie89
    I have a small problem with converting a bitmap to a Texture2D. The resulted image of the conversion has the red channel switched with the blue channel :/ I don't know why, because the pixel formats are the same. If someone can help me I will be very happy :) System.Drawing.Image image = System.Drawing.Bitmap.FromFile(ImageFileLoader.filename); System.Drawing.Bitmap bitmap = new System.Drawing.Bitmap(image); Texture2D mapTexture = new Texture2D(Screen.Game.GraphicsDevice, bitmap.Width, bitmap.Height,false,SurfaceFormat.Color); System.Drawing.Imaging.BitmapData data = bitmap.LockBits(new System.Drawing.Rectangle( 0, 0, bitmap.Width, bitmap.Height), System.Drawing.Imaging.ImageLockMode.ReadOnly,System.Drawing.Imaging.PixelFormat.Format32bppArgb); byte[] bytes = new byte[data.Height * data.Width*4]; System.Runtime.InteropServices.Marshal.Copy(data.Scan0, bytes, 0, bytes.Length); mapTexture.SetData<byte>(bytes, 0, data.Height * data.Width * 4); bitmap.UnlockBits(data); bitmap.Dispose(); image.Dispose();

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  • Why google is not crawling my website

    - by Aman Virk
    I am running a design and development blog http://www.thetutlage.com/ . From last couple of days my search traffic have been reduced from 70% to 10%. I myself is against black hat seo and all it do is write my own unique content almost everyday. Last week my search traffic was really good but now is dropping like heck. I have checked my webmasters dashboard and no message there from google. When i checked server logs i came to know last time google crawled my website was on 27 september 2012. Really i have no idea what i am doing wrong. I follow all google guidelines like bible, please help me

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  • Strange GTK3 issue with Audacious and Evince (Document Viewer)

    - by Sman789
    I find that, in some GTK3 apps such as Audacious and Evince (Document Viewer), parts of the UI are pure black, which looks ugly and out-of-place. It is not intentional, as the screenshots on both websites show the app looking different. I only have this issue with the Adwaita GTK theme, but since it comes with Gnome 3 and is the main theme these apps are designed for, I'm guessing the problem is not simply the theme having some bug (though the Ubuntu package might). I have had this issue on two laptops now, running both Ubuntu 12.04 and Xubunu 12.10 with Gnome Shell and Adwaita. The screenshots below show the problem: Audcious's is visible in the search area around the text box, and behind the playlist tabs, and Evince's is visible in more or less the same position and around the document itself. Compare this from the Audacious homepage: With this image from my system: And Evince too:

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  • Fedora login gone after Ubuntu updates on a dual boot

    - by andrew
    After a software update for Ubuntu, my dual boot with Fedora will not show Fedora in the start menu. It just boots into Ubuntu and when I hold Shift and boot, it only has Ubuntu in the list. I have tried the post about installing grub-customizer but when I run that, I get Reading package lists... Done Building dependency tree Reading state information... Done E: Unable to locate package grub-customizer I cannot find any other way to fix this problem. I am a complete newbie to Linux.

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  • Unity-Animation parameters are not being set

    - by user1814893
    I have the following animation controller: with two parameters of walkingSpeed and Jump. I have the following code which should change the values: animator.SetFloat("walkingSpeed",0.9f); animator.SetBool("Jump",true); and animator is the correctly referenced animator object. However the values that the parameters are set to do not appear to change in the animator window, nor do they appear to impact what is happening on the screen. However they do seem to impact the values obtained when doing the following: animator.GetFloat("walkingSpeed"); The animator consists of the shown blend tree, which works correctly and is always active, however due to the values not being changed it does not blends, and always acts as if the value with which it blends (walkingSpeed is 0). What is going on?

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  • 2D SAT How to find collision center or point or area?

    - by Felipe Cypriano
    I've just implemented collision detection using SAT and this article as reference to my implementation. The detection is working as expected but I need to know where both rectangles are colliding. I need to find the center of the intersection, the black point on the image above. I've found some articles about this but they all involve avoiding the overlap or some kind of velocity, I don't need this. I just need to put a image on top of it. Like two cars crashed so I put an image on top of the collision. Any ideas? ## Update The information I've about the rectangles are the four points that represents them, the upper right, upper left, lower right and lower left coordinates. I'm trying to find an algorithm that can give me the intersection of these points.

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  • Flash doesn't work any more on 10.04

    - by Béné
    I have a very strange problem with flash on my 10.04 system. (An update to 12.04 is not an option, because the system is just too old and slow.) After a recent update flash has just stopped working altogether. Youtube just shows a white square, vimeo a black one. After a 10.04 reinstall the problem stays the same. Not even chrome displays flash content, just a message that shockwave flash could not be loaded. 'ubuntu-restricted-extras' 'flashplugin-nonfree' and 'flashplugin-installer' are all installed in version 11.2.202.238ubuntu0.10.04.1.

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  • Coherence Warnings in WLS

    - by john.graves(at)oracle.com
    With 11g (10.3.4 WLS), coherence is now built into many applications.  I’ve been noticing errors in my OSB logs like these:####<10/03/2011 10:45:40 AM EST> <Warning> <Coherence> <osb-jeos> <osb_server1> <Logger@324239121 3.6.0.4> <<anonymous>> <> <583c1 0bfdbd326ba:-8c38159:12e9d02c829:-8000-0000000000000003> <1299714340643> <BEA-000000> <Oracle Coherence 3.6.0.4 (member=n/a): Unic astUdpSocket failed to set receive buffer size to 714 packets (1023KB); actual size is 12%, 89 packets (127KB). Consult your OS do cumentation regarding increasing the maximum socket buffer size. Proceeding with the actual value may cause sub-optimal performanc e.> ####<10/03/2011 10:45:40 AM EST> <Warning> <Coherence> <osb-jeos> <osb_server1> <Logger@324239121 3.6.0.4> <<anonymous>> <> <583c1 0bfdbd326ba:-8c38159:12e9d02c829:-8000-0000000000000003> <1299714340650> <BEA-000000> <Oracle Coherence 3.6.0.4 (member=n/a): Pref erredUnicastUdpSocket failed to set receive buffer size to 1428 packets (1.99MB); actual size is 6%, 89 packets (127KB). Consult y our OS documentation regarding increasing the maximum socket buffer size. Proceeding with the actual value may cause sub-optimal p erformance.> ####<10/03/2011 10:45:40 AM EST> <Warning> <Coherence> <osb-jeos> <osb_server1> <Logger@324239121 3.6.0.4> <<anonymous>> <> <583c1 0bfdbd326ba:-8c38159:12e9d02c829:-8000-0000000000000003> <1299714340659> <BEA-000000> <Oracle Coherence 3.6.0.4 (member=n/a): Mult icastUdpSocket failed to set receive buffer size to 714 packets (1023KB); actual size is 12%, 89 packets (127KB). Consult your OS documentation regarding increasing the maximum socket buffer size. Proceeding with the actual value may cause sub-optimal performa nce.> I was able to “fix” this on my ubuntu system by adding the following lines to the /etc/sysctl.conf file:# Setup networking for coherence # maximum receive socket buffer size, default 131071 net.core.rmem_max = 2000000 # maximum send socket buffer size, default 131071 net.core.wmem_max = 1000000 # default receive socket buffer size, default 65535 net.core.rmem_default = 2524287 # default send socket buffer size, default 65535 net.core.wmem_default = 2524287 .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; }   .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; }

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  • Can't untar Testdisk 6.14 using live CD

    - by Orestes
    I'm using an Ubuntu LiveCD right now and need to recover files from a (Windows 7) partition. I've read about TestDisk and tried downloading it and untaring it but: testdisk-6.14-WIP.linux26.tar.bz2: Cannot open: No such file or directory tar (child): Error is not recoverable: exiting now tar: Child returned status 2 tar: Error is not recoverable: exiting now I don't know why it doesn't work (noob). I tried using sudo apt-get install testdisk but: Reading package lists... Done Building dependency tree Reading state information... Done E: Unable to locate package testdisk so.... HELP :D

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  • Blurry vertical sections using fglrx with Radeon hd 6970

    - by Jesus Ramos
    So I managed to get fglrx working by downloading the drivers from ATI because the ones from additional drivers boot to a black screen and the open source dont let me change resolution. My one issue is that half of my monitor is fine and the other half is blurry almost as if there's a blurry vertical stripe on the right side. I tried disabling Compiz and have the same issue in both gnome and kde, I was wondering if theres an xorg.conf change that could be made to fix this as I have already set the resolution and refresh rates to the correct values.

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  • subprocess installed post-installation script returned error exit code 1

    - by Laura quintero
    I had installed snort on ubuntu 11.04 and uninstall it because I had problems, to reinstall it leaves a problem: Reading package lists ... done Building dependency tree Reading state information ... done Calculating upgrade ... ready 0 upgraded, 0 newly installed, 0 to remove and 0 not upgraded. 1 not fully installed or removed. 0 B will be used for additional disk space after this operation. Do you want to continue [S / n]? s Configuring snort (2.8.5.2-9.1) ... * Stopping Network Intrusion Detection System snort * - No running snort instance found * Starting Network Intrusion Detection System snort [fail] invoke-rc.d: initscript snort, action "start" failed. dpkg: error processing snort (- configure): subprocess installed post-installation script returned error exit code 1 Errors were encountered while processing: snort E: Sub-process / usr / bin / dpkg Returned an error code (1) any solution? Commands allready used apt-get clean apt-get remove snort sudo apt-get dist-upgrade dpkg - remove - force-remove-reinstreq snort and nothing.

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  • jWIN JC-AM100 not working

    - by Tony Kilgore
    jWIN JC-AM100 not working in skype, i just see black and the little light that comes on the webcam showing its in use does not come on ether, but it works with cheese but its upside down. =[ lsusb: Bus 002 Device 012: ID 093a:2620 Pixart Imaging, Inc. Bus 002 Device 002: ID 04d9:1702 Holtek Semiconductor, Inc. Bus 002 Device 005: ID 046d:c05a Logitech, Inc. Optical Mouse M90 Bus 002 Device 004: ID 058f:9360 Alcor Micro Corp. 8-in-1 Media Card Reader Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub Bus 002 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub<

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  • Downgrade to LTS version, preserving /home partition: Should I expect this to work?

    - by Archelon
    Specifically, I'm installing Kubuntu 12.04 over 13.04. And in fact I've already done it, and it seems to have at least mostly worked, but I'm wondering whether this one anomaly is likely to be attributable to the downgrade; to wit: I have no window borders|decorations, but only wide, featureless, white---or sometimes black---margins around all my windows. None of the settings in System Settings (the window border and decorations options are in Workspace Appearance) seem to have any effect. Is this likely to be fixable, or should I cut my losses and reinstall (formatting the /home partition and restoring any data with rsync)?

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  • What's a good data structure solution for a scene manager in XNA?

    - by tunnuz
    Hello, I'm playing with XNA for a game project of myself, I had previous exposure to OpenGL and worked a bit with Ogre, so I'm trying to get the same concepts working on XNA. Specifically I'm trying to add to XNA a scene manager to handle hierarchical transforms, frustum (maybe even occlusion) culling and transparency object sorting. My plan was to build a tree scene manager to handle hierarchical transforms and lighting, and then use an Octree for frustum culling and object sorting. The problem is how to do geometry sorting to support transparencies correctly. I know that sorting is very expensive if done on a per-polygon basis, so expensive that it is not even managed by Ogre. But still images from Ogre look right. Any ideas on how to do it and which data structures to use and their capabilities? I know people around is using: Octrees Kd-trees (someone on GameDev forum said that these are far better than Octrees) BSP (which should handle per-polygon ordering but are very expensive) BVH (but just for frustum and occlusion culling) Thank you Tunnuz

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  • Dual Screen with 12.04 ATI randr extension is not present

    - by Trevor Pearson
    Here's my problem I have two screens. One is a 22"led monitor and the other is 42 inch led tv. In windows 7 I run xbmc on the second monitor. I'm trying to mimic the same function in setting xbmc to display on the tv only. So I installed the latest x64 linux drivers from ATI. I configured (using the catalyst control panel) using single display (multi desktop) I then got a white screen with black x so I enable xinerama. with xinerama enable I got the displays to work correctly, however I received an error when I tried to enter display settings to change the launcher location. the error message was " "randr extension not present =" So I tried to install libxandr2 using terimal but here's what I get trev@Lrig:~$ sudo get-apt install libxander2 [sudo] password for trev: sudo: get-apt: command not found I'm at a loss now because I can't find a solution for the xandr error message. I'f my specs are important amd athx2 6400+ ghz 8 gigs ram radeon hd6950

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  • 3D BSP rendering for maps made in 2d platform style

    - by Dev Joy
    I wish to render a 3D map which is always seen from top, camera is in sky and always looking at earth. Sample of a floor layout: I don't think I need complex structures like BSP trees to render them. I mean I can divide the map in grids and render them like done in 2D platform games. I just want to know if this is a good idea and what may go wrong if I don't choose a BSP tree rendering here. Please also mention is any better known rendering techniques are available for such situations.

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  • Polite busy-waiting with WRPAUSE on SPARC

    - by Dave
    Unbounded busy-waiting is an poor idea for user-space code, so we typically use spin-then-block strategies when, say, waiting for a lock to be released or some other event. If we're going to spin, even briefly, then we'd prefer to do so in a manner that minimizes performance degradation for other sibling logical processors ("strands") that share compute resources. We want to spin politely and refrain from impeding the progress and performance of other threads — ostensibly doing useful work and making progress — that run on the same core. On a SPARC T4, for instance, 8 strands will share a core, and that core has its own L1 cache and 2 pipelines. On x86 we have the PAUSE instruction, which, naively, can be thought of as a hardware "yield" operator which temporarily surrenders compute resources to threads on sibling strands. Of course this helps avoid intra-core performance interference. On the SPARC T2 our preferred busy-waiting idiom was "RD %CCR,%G0" which is a high-latency no-nop. The T4 provides a dedicated and extremely useful WRPAUSE instruction. The processor architecture manuals are the authoritative source, but briefly, WRPAUSE writes a cycle count into the the PAUSE register, which is ASR27. Barring interrupts, the processor then delays for the requested period. There's no need for the operating system to save the PAUSE register over context switches as it always resets to 0 on traps. Digressing briefly, if you use unbounded spinning then ultimately the kernel will preempt and deschedule your thread if there are other ready threads than are starving. But by using a spin-then-block strategy we can allow other ready threads to run without resorting to involuntary time-slicing, which operates on a long-ish time scale. Generally, that makes your application more responsive. In addition, by blocking voluntarily we give the operating system far more latitude regarding power management. Finally, I should note that while we have OS-level facilities like sched_yield() at our disposal, yielding almost never does what you'd want or naively expect. Returning to WRPAUSE, it's natural to ask how well it works. To help answer that question I wrote a very simple C/pthreads benchmark that launches 8 concurrent threads and binds those threads to processors 0..7. The processors are numbered geographically on the T4, so those threads will all be running on just one core. Unlike the SPARC T2, where logical CPUs 0,1,2 and 3 were assigned to the first pipeline, and CPUs 4,5,6 and 7 were assigned to the 2nd, there's no fixed mapping between CPUs and pipelines in the T4. And in some circumstances when the other 7 logical processors are idling quietly, it's possible for the remaining logical processor to leverage both pipelines. Some number T of the threads will iterate in a tight loop advancing a simple Marsaglia xor-shift pseudo-random number generator. T is a command-line argument. The main thread loops, reporting the aggregate number of PRNG steps performed collectively by those T threads in the last 10 second measurement interval. The other threads (there are 8-T of these) run in a loop busy-waiting concurrently with the T threads. We vary T between 1 and 8 threads, and report on various busy-waiting idioms. The values in the table are the aggregate number of PRNG steps completed by the set of T threads. The unit is millions of iterations per 10 seconds. For the "PRNG step" busy-waiting mode, the busy-waiting threads execute exactly the same code as the T worker threads. We can easily compute the average rate of progress for individual worker threads by dividing the aggregate score by the number of worker threads T. I should note that the PRNG steps are extremely cycle-heavy and access almost no memory, so arguably this microbenchmark is not as representative of "normal" code as it could be. And for the purposes of comparison I included a row in the table that reflects a waiting policy where the waiting threads call poll(NULL,0,1000) and block in the kernel. Obviously this isn't busy-waiting, but the data is interesting for reference. _table { border:2px black dotted; margin: auto; width: auto; } _tr { border: 2px red dashed; } _td { border: 1px green solid; } _table { border:2px black dotted; margin: auto; width: auto; } _tr { border: 2px red dashed; } td { background-color : #E0E0E0 ; text-align : right ; } th { text-align : left ; } td { background-color : #E0E0E0 ; text-align : right ; } th { text-align : left ; } Aggregate progress T = #worker threads Wait Mechanism for 8-T threadsT=1T=2T=3T=4T=5T=6T=7T=8 Park thread in poll() 32653347334833483348334833483348 no-op 415 831 124316482060249729303349 RD %ccr,%g0 "pause" 14262429269228623013316232553349 PRNG step 412 829 124616702092251029303348 WRPause(8000) 32443361333133483349334833483348 WRPause(4000) 32153308331533223347334833473348 WRPause(1000) 30853199322432513310334833483348 WRPause(500) 29173070315032223270330933483348 WRPause(250) 26942864294930773205338833483348 WRPause(100) 21552469262227902911321433303348

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  • Cannot install nodejs and npm

    - by user809829
    I'm trying to install nodejs and npm, however, it fails. This is my terminal: sudo apt-get install nodejs npm Reading package lists... Done Building dependency tree Reading state information... Done Some packages could not be installed. This may mean that you have requested an impossible situation or if you are using the unstable distribution that some required packages have not yet been created or been moved out of Incoming. The following information may help to resolve the situation: The following packages have unmet dependencies: nodejs : Conflicts: npm E: Unable to correct problems, you have held broken packages. What to do? I'm kinda lost :(

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  • Java serait un "Roi légèrement enrhumé", un cadre de Google appelle Oracle à le remettre d'aplomb

    Java serait un "Roi légèrement enrhumé" Pour un cadre de Google qui appelle Oracle à le remettre d'aplomb Josh Blosh, "Chief Java Architect" chez Google, vient de participer au Red Hat Middleware 2020. Lors d'une intervention particulièrement remarquée, il a regretté que la plate-forme Java soit « restée sans maître à bord (rudderless) depuis plusieurs années ». D'après lui, un malaise durable se serait même emparé de la communauté. La principale explication tiendrait au fait que « les disputes techniques et liées aux licences », particulièrement préjudiciables, ont « sapé l'énergie de la communauté et provoqué beaucoup de mauvaise presse »

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    - by Asian Angel
    This week we learned how to quickly cut a clip from a video file with Avidemux, “tile windows, remote control a desktop using an iOS device, taking advantage of Windows 7 libraries”, turn a home Ubuntu PC into a LAMP web server, enable desktop notifications for Gmail in Chrome, “what image channels are and what they mean”, and more Latest Features How-To Geek ETC How to Integrate Dropbox with Pages, Keynote, and Numbers on iPad RGB? CMYK? Alpha? What Are Image Channels and What Do They Mean? How to Recover that Photo, Picture or File You Deleted Accidentally How To Colorize Black and White Vintage Photographs in Photoshop How To Get SSH Command-Line Access to Windows 7 Using Cygwin The How-To Geek Video Guide to Using Windows 7 Speech Recognition Android Notifier Pushes Android Notices to Your Desktop Dead Space 2 Theme for Chrome and Iron Carl Sagan and Halo Reach Mashup – We Humans are Capable of Greatness [Video] Battle the Necromorphs Once Again on Your Desktop with the Dead Space 2 Theme for Windows 7 HTC Home Brings HTC’s Weather Widget to Your Windows Desktop Apps Uninstall Batch Removes Android Applications

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