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  • Blank screen when "boot from USB"

    - by Nathan
    OK so, here is what I have done: I downloaded the iso "ubuntu-12.04-desktop-amd64" I used "Universal-USB-Installer-1.9.0.0" to make a bootable USB I restart PC and change the boot option to USB HDD I get the menu to: Boot from USB Install to Hard drive Help etc When I click Boot from USB or Install to hard drive, loads of text flies past and then I get a blank screen and I cant see anything? What can I do so I can see the installation screen? Im using a dual monitor setup from my GFX card and my main display is on my HDMI port to my TV.

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  • Blank desktop after login

    - by Alex
    Today my 14.04 updated itself not requiring a reboot. After a while I rebooted because of other reasons and then I was pleasantly surprised by a blank screen. I have tried everything I could think about including Reinstalled compiz, unity, ubuntu-desktop, xorg Reinstalled and then removed the nvidia driver So far nothing has worked. Except for one little thing: my cairo-dock is showing. And that's all. I tried with Unity doesn't load, no Launcher, no Dash appears, but none of the answers there helped me. I also tried removing my ~/.Xauthority file and it still doesn't work. Does anybody know what else I could try? UPDATE: sudo dpkg-reconfigure xserver-xorg sudo service lightdm stop sudo service lightdm start When I run that code and then login again the icons on the desktop are displayed but the menu and the launcher are still not there. Also, when I try to run an application from CTRL + ALT + F1 such as dconf reset -f /org/compiz/ it says Cannot autolaunch D-Bus without X11 $DISPLAY I can only run applications with export DISPLAY=:0

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  • Dell Inspiron 1210 mini Blank Screen on boot 12.04

    - by jrod
    Dell Inspiron 1210 mini Blank Screen on boot 12.04 If I mash buttons I get to a gray screen then the login screen and into the desktop but normally I turn on the laptop and I see a black screen with a cursor then a purple screen then it just goes black. I can hit ctrl alt F1 or F2 and get a prompt. I've tried using the poulsbo ppa driver script fix but that doesn't work. I don't knwo what to do now. I have the OS installed and when I did get into the OS by mashing buttons I installed updates and wireless adapter drivers. It works but if I reboot I jsut get to the black screen and have no idea what to do. What needs to be done so that I can just boot up and see the login screen!?

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  • laptop screen goes blank after waking from sleep

    - by Tojo Chacko
    I have been facing this issue from the last week after some update. Whenever my laptop wakes up from suspend state it just shows me a blank screen. Regardless of whatever I do(move my mouse, press keyboard buttons) it just refuses to wake up. I am forced to do a restart and lose all my unsaved files. Has this issue been reported for Ubuntu 12.04? I am using a Lenovo X200 with Intel Mobile 4 Series Graphics Chipset. Please let me know if any body has found a fix for this.

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  • Blank Screen on 12.04

    - by stupidwhiteguy
    Can hit Ctrl-Alt-F1 and login but no fixes work. Tried nomodeset and everything else appears to have upgraded but can't see anything. I really need this computer to work. It is an old Dell with 1.6 processor with old school monitor. I don't know why people are giving my question negative votes. If you know how to fix this, then please help me, as I have read and tried all the solutions that I've found. Just for the record reformatting is not fixing it, and I can't get a boot CD to load either. If you know how to use the blank screen fix tutorial, please explain cos I'm lost. Most people don't understand this stuff and an easy "how-to" fix would be nice.

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  • Blank lines between sourcecode [closed]

    - by manix
    I'm so confused with a strange behaviour. Actually I have edited some php files remotely with my PhpDesigner8 (a php editor). Everything goes right, but when my teammates reopen the files that I have edited the source code have blank lines like below: class AdminController extends Controller { function __construct() { parent::__construct(); if (!$this->session->can_admin()) { show_error('Solo para administradores.'); } $this->load->library('backend'); } } Instead of class AdminController extends Controller { function __construct() { parent::__construct(); if (!$this->session->can_admin()) { show_error('Solo para administradores.'); } $this->load->library('backend'); } } Did you have experience these kinds of problems?

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  • Chrome start page: no "Most Visited" nor "Apps", just "Blank" wanted

    - by Robottinosino
    Google Chrome Version 22.0.1229.79 on OS X 10.8.2 How can I get just a plain blank page as my home page, not just a list of "Most Visited" sites or "Apps" installed, please? I did try using the about:blank and/or javacript:void() workaround from these sources: http://productforums.google.com/forum/#!category-topic/chrome/discuss-chrome/xTKRGDi6Rb4 How to make a blank page in Google chrome at start-up? Note the UI has changed since this and I am confused: Chrome "New Tab Page" not showing most frequently visited pages I prefer not to install extensions from unknown sources, like recommended here: Make Chrome New Tab Totally Blank

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  • Nginx - Serve blank page on "Bad Gateway" error

    - by TheLittleCheeseburger
    Hello all. I want to use Nginx as a simple reverse proxy, but if the server behind Nginx is down I just was to display a blank page. For some reason this configuration isn't displaying a blank page on error 502 and I can't figure out why. Thanks for your help! user www-data; worker_processes 1; error_log /var/log/nginx/error.log; pid /var/run/nginx.pid; events { worker_connections 1024; use epoll; # multi_accept on; } http { keepalive_timeout 65; proxy_read_timeout 200; upstream tornado { server 127.0.0.1:8001; } server { listen 80; server_name www.something.com; location / { error_page 502 = @blank; proxy_pass http://tornado; } location @blank { index index.html; root /web/blank; } } }

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  • add blank for 0 result into existing formula

    - by Tom
    is there any way to use this formula [<30,0,1)) for a group of cells in Sheet1!(A14:I100)] and if result == 0 insert blank or add [=IF(O16=0,"",] somehow so all 0 results just show a blank result. I'm just not sure how to add this to my formula so if Cell a176= 07:48:16 and formula [<30,0,1)) for a group of cells in Sheet1!(A14:I100)] changes it to 468, all is good - however if Cell a176= 00:00:16, the result is "0" - I would like the result to be "" blank "" instead of "0". any ideas??

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  • Reclaim Vertical UI Space by Adding a Toolbar to the Left or Right Side of Firefox

    - by Asian Angel
    Do you need to make the most efficient use possible of vertical UI space on your system’s screen, but have horizontal space to spare? Now you can shift the toolbar icons and their awesome functionality to a slim sidebar in Firefox using the Vertical Toolbar extension. As you can see above the sidebar even picked up on our Personas Theme to help it blend in nicely with the rest of the browser. You can access the options for the new toolbar by right clicking within the toolbar area. These are the options for the toolbar…you can choose the side of Firefox that works best for toolbar placement, adjust display, hiding, & animation settings, define how the buttons display, and add/remove additional buttons as desired. Once you open the Customize Toolbar Window make any desired additions or removals just like you would before on the top UI section and close when finished. Note: Works with Firefox 4.0b7pre – 4.0.* Vertical Toolbar [Mozilla Add-ons] Latest Features How-To Geek ETC How to Enable User-Specific Wireless Networks in Windows 7 How to Use Google Chrome as Your Default PDF Reader (the Easy Way) How To Remove People and Objects From Photographs In Photoshop Ask How-To Geek: How Can I Monitor My Bandwidth Usage? Internet Explorer 9 RC Now Available: Here’s the Most Interesting New Stuff Here’s a Super Simple Trick to Defeating Fake Anti-Virus Malware Comix is an Awesome Comics Archive Viewer for Linux Get the MakeUseOf eBook Guide to Speeding Up Windows for Free Need Tech Support? Call the Star Wars Help Desk! [Video Classic] Reclaim Vertical UI Space by Adding a Toolbar to the Left or Right Side of Firefox Androidify Turns You into an Android-style Avatar Reader for Android Updates; Now with Feed Widgets and More

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  • Sharing My Thoughts on Space Flight

    - by Grant Fritchey
    This went out in the DBA newsletter from Red Gate, but I enjoyed writing it so much, I thought I'd share it to a wider audience: I grew up watching the US space program. I watched men walk on the moon for the first time in 1969, when I was only six years old. From that moment on, I dreamed of going into space. I studied aeronautics and tried to get into the Air Force Academy, all in preparation for my long career as an astronaut. Clearly, that didn't quite work out for me. But it sure could for you. At Red Gate, we're running a new contest: DBA in Space. The prize is a sub-orbital flight. When I first got word of this contest, my immediate response was, "And you need me to go right away and do a test flight? Excellent!" No, no test flight needed, plus I was pretty low on the list of volunteers. "That's OK, I'll just enter." Then I was told that, as a Red Gate employee, I couldn't win. My next response was, "I quit".eventually, I was talked down off the ledge, and agreed to help make this special for some other DBA. Many (most?) of us are science fiction fans, either the soft science of Star Trek and Star Wars, or the hard science of Niven and Pournelle, or Allen Steele. We watched the Shuttles go up and land. We've been dreaming of our own trips into orbit and our vacation-home on the Moon for a long, long time. All that might not arrive on schedule, but you've got a shot at breaking clear of the atmosphere. The first stage is a video quiz, starring Brad McGehee, and it's live at www.DBAinSpace.com now. Go for it. Good luck and God speed!

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  • JavaScript 3D space ship rotation

    - by user36202
    I am working with a fairly low-level JavaScript 3D API (not Three.js) which uses euler angles for rotation. In most cases, euler angles work quite well for doing things like aligning buildings, operating a hovercraft, or looking around in the first-person. However, in space there is no up or down. I want to control the ship's roll, pitch, and yaw. To do that, some people would use a local coordinate system or a permenant matrix or quaternion or whatever to represent the ship's angle. However, since I am not most people and am using a library that deals exclusively in euler angles, I will be using relative angles to represent how to rotate the ship in space and getting the resulting non-relative euler angles. For you math nerds, that means I need to convert 3 euler angles (with Y being the vertical axis, X representing the pitch, and Z representing a roll which is unaffected by the other angles, left-handed system) into a 3x3 orientation matrix, do something fancy with the matrix, and convert it back into the 3 euler angles. Euler to matrix to euler. Somebody has posted something similar to this on SO (http://stackoverflow.com/questions/1217775/rotating-a-spaceship-model-for-a-space-simulator-game) but he ended up just working with a matrix. This will not do for me. Also, I am using JavaScript, not C++. What I want essentially are the functions do_roll, do_pitch, and do_yaw which only take in and put out euler angles. Many thanks.

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  • No space left on disk

    - by Ned
    folks. I'm trying to copy/move files to an external 1 TB hard drive with about 50 GB remaining space. I receive a "no space left on disk" when I try. I've moved files off and retried, but still get the same message. Disk Usage Analyzer, Properties, and freeware Treesize all report available hard drive space of about 50 GB. I've tried df -i (50 GB available) and df -k, with the latter reporting only 1% of inode usage. I've been able to save files from Firefox to the drive also. I can't even rename files without getting the message. Yesterday in the midst of trying to figure this out I tried to move 4 files to the drive and got the message. Today, I found them on the drive. What's up with that? (That's the only time that has happened to my knowledge.) Is this an ubuntu problem? or is my hard drive just about to fail because of something like a controller problem? Any thoughts would be appreciated.

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  • LibGDX drawing map using tiles without space

    - by Enayat Muradi
    I am making a board game. To draw the map on the board I use different tiles. On some screen the map looks good but on some other screens there is a space between the tiles. How can I do so there won't be any space between the tiles? I am designing my game with the size 480x800. To fit other screens I stretch it. My tiles looks like this: I draw the map using a for loop to draw the tile in different (x,y) position on screen. Here is what I mean with space between tiles: Screen with 240x400 Screen with 360x600, here there is no spacing between tiles. I use camera and the screen to draw I don't use stage. I have also tried to use Viewport but I get the same results. cam = new OrthographicCamera();cam.setToOrtho(true, gameWidth, gameHeight); batcher = new SpriteBatch(); batcher.setProjectionMatrix(cam.combined); shapeRenderer = new ShapeRenderer(); shapeRenderer.setProjectionMatrix(cam.combined); How can I do to solve the problem?

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  • Getting file system free space

    - by Fred Riley
    This isn't a problem as such, more a request for information based on ignorance of the Linux filesystem. The very short question is: How do I find out how much free and used space there is on the volume from which Ubuntu is running? More detail: I'm running Ubuntu 12.04 from a 64Gb USB3 stick, created from booting up a year-old Ubuntu 12.04 DVD and running Startup Disk Creator. The reason for this is that the Master Boot Record on my hard disk, holding Windoze 7, has gone belly-up, and whilst awaiting a recovery disk I'm running Ubunto off USB or DVD as a 'trial'. (And will continue to run Ubuntu after restoring Windoze, as I've rediscovered my love of the penguin :o)) After installing Ubuntu on the stick I ran the software update app, which downloaded some 450Mb of updates and took a couple of hours to install to the stick. A couple of times I got a message saying that disk space was short. So I looked in the file manager (or whatever it's called these days) and couldn't see the stick listed, just: SYSTEM hard disk (listed as 479Gb Filesystem) two other partitions that had been created by Windoze "4.3GB Filesystem" which when I try to open gives the error "Could not find /cow", and when I try to unmount it tells me I can't because it's not mounted - D'OH!! Edit: screenshot of file manager Edit: screenshot of low disk space warning What I can't see is the USB stick from which I'm running Ubuntu. Where's it gone, anybody know? This is tangentially related to a previous question of mine about system tools, in that I'm trying to get control and knowledge of the system in the newest incarnation of Ubuntu.

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  • btrfs and missing free space

    - by easteregg
    I converted my ext4 partition to btrfs and deleted the save subvolume after doing so. Then I enabled the compression (lzo) of the filessystem in the fstab file and everything is correct so far. Then I forced the compression of all files using the defragmentation command with the parameter -c that the new compression is applied to all files. While doing so, I noticed that my ssd got completly filled up - before I had 6gigs of free space. No I got nothing left. easteregg@x201s:~$ btrfs fi df / Data: total=50.00GB, used=49.17GB System: total=32.00MB, used=4.00KB Metadata: total=24.50GB, used=9.86GB and easteregg@x201s:~$ df -ha Filesystem Size Used Avail Use% Mounted on /dev/sda1 75G 60G 852M 99% / So now. How can I regain my free space. I expected to gain more space because of the lzo compression. And now! The fs is correctly mounted. easteregg@x201s:~$ mount /dev/sda1 on / type btrfs (rw,noatime,ssd,compress=lzo) Any ideas how to fix this issue?

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  • Cinnamon Settings Panel Blank After v 2.0.6

    - by Cinnamon Challenge
    After cinnamon upgrade to 2.0.6-20131026040307-precise via synaptic, the "cinnamon settings" gui or window is broken. It appears blank, only showing the configuration category icons for "Appearance", "Preferences", "Hardware", and "Administration". The icons that should be within these categories are gone. I don't know if cinnamon-control-center was removed during the last cinnamon update, but this issue began on Oct. 25. When running cinnamon-settings from terminal, several errors appear such as this: Could not load screen module; is the cinnamon-control-center package installed? /usr/lib/cinnamon-settings/modules/cs_user.py:112: Warning: g_object_unref: assertion `G_IS_OBJECT (object)' failed file_icon = Gio.FileIcon().new(file) (cinnamon-settings.py:5471): Gtk-WARNING **: Attempting to add a widget with type GtkImage to a GtkMenuItem, but as a GtkBin subclass a GtkMenuItem can only contain one widget at a time; it already contains a widget of type GtkAccelLabel Could not find network module; is the cinnamon-control-center package installed? cinnamon-control-center is not installed in synaptic, and when the module is marked for installation, unity is selected for removal. Is there any way to get this function back without removing unity? Release: Ubuntu 12.04 (precise) Kernel: 3.2.0-55-generic Desktop: Cinnamon 2.0.6-20131026040307-precise Some settings are still accessible through terminal by appending the name of the function to the command: cinnamon-settings panel cinnamon-settings calendar cinnamon-settings themes cinnamon-settings applets cinnamon-settings windows cinnamon-settings fonts cinnamon-settings hotcorner

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  • Domain forwarding to a IE "trusted site" opens a blank page

    - by Michael Jasper
    My employer, a University, regularly hosts conferences and other events. While websites for these sites are hosted on our domain, they frequently request customized .com urls. We then forward these domains to the specific site. Recently, we discovered a problem, where a page will not load if the following conditions are met(using a current example): website is created on our CMS for a conference http://continue.weber.edu/nulc a domain is created http://www.nulc2012.com and forwarded to http://continue.weber.edu/nulc The user enters http://www.nulc2012.com into their address bar using IE7 or IE8 The user has *.weber.edu listed as a "trusted site" in IE security settings (the case for nearly all on-campus computers) When this happens, their browser will correctly transfer to the page http://continue.weber.edu/nulc/index.php, however the page is blank, returning only: <!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN"> <HTML><HEAD> <META content="text/html; charset=windows-1252" http-equiv=Content-Type></HEAD> <BODY></BODY></HTML> Is there any know solution to this problem? Or am I missing something completely? Note: Tested websites do load correctly in Chrome, Firefox, and Safari

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  • Blank screen after GRUB (64 bit) - cannot install Ubuntu

    - by peGGi
    My laptop's specs: Lenovo IdeaPad Z570 Intel Core i5-2410M @ 2.3Ghz 6 Gb RAM DDR3 640 Gb ATAPI Hard-disk Drive @ 5,200 RPM NVIDIA GeForce G520M with Optimus switching technology Broadcom 802.11n Network Adapter REALTEK soundcard Windows 7 Home Premium 64-bit I downloaded Ubuntu Studio 11.04 and burned the iso image onto two different DVDs, using two different programs (one DVD is RW, the other is just R). I verified the hash MD5sum thing. I get as far as GRUB with the 4 options (install, advanced install, disk verification, system rescue) but no matter which one I select, I get a blank screen and nothing happens. The DVD drive spins down after about 30 seconds. Also just before the GRUB screen I get a message saying Error: "Prefix" is not set. I'm not sure if that's relevant. I have tried all the options using both DVDs. Same thing happens. I have changed the graphics setting in BIOS to UMA or Optimus, but still happens either way. I've tried booting with the wireless switch turned off, same thing happens. I downloaded 'vanilla' Ubuntu 64-bit and burned onto a CD, and the same thing happens. I have downloaded Ubuntu 32-bit and I am able to boot from the live CD (interestingly the wireless card won't work, but that's maybe another issue). I have searched extensively through these forums and other sites but I can't see anything that will help me. Is there something I'm missing? I'd really appreciate help on this. The laptop is less than 2 weeks old. I was so looking forward to getting Ubuntu Studio up and running. I've gone about as far as my technical abilities will allow.

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  • Blank Screen after inactive time

    - by Hari K T
    I am using Ubuntu 11.04 , on a DELL Vostro 1510. If I am inactive for a certain time, the screen usually gets locked and the login prompt will be there. Yes sometimes I am able to see the login screen and logging in as normal. But sometimes after its locked and when the mouse or keyboard is moved also nothing happens. This is happening for the second time. And its not happening always . I can switch from one terminal to other from the locked screen with Alt + + Ctrl F1 etc . But when I switch to the graphical one with Alt + Ctrl + F7 ( from the locked time ) I can see only a blank screen. I tried once login in ( Alt + Ctrl + F1 ) and trying to startx, but it said something was locked and want to delete the lock and try. So I removed don't remember what exactly it was . But it too was not a success , I was forced to press the powerbutton. Is this a bug ? I saw some but all are happening for switching users. Never experienced after logging out, but this happens only when its locked automatically actually. Update : I strongly feel this is a Bug. As I upgraded to 11.10 , I didn't noticed the same issues. But at some point if any one has an answer, you can post it. I can approve.

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  • Blank pale blue screen with Live USB Kubuntu on AMD Sempron 2800+ processor

    - by WGCman
    I am trying to install Kubuntu onto a USB stick to use on my Acer Aspire 1362 laptop with an AMD Sempron 2800+ chip. Using Windows XP, I downloaded and saved to the laptop's hard drive: kubuntu-2.04.1-desktop-i386.iso from the GetKubuntu website and LinuxLive USB Creator 2.8.16.exe from the Linux live website I then installed the latter and ran it, installing the kubuntu onto the Memory stick. Leaving the Bios setup unchanged, the USB stick is ignored and Windows boots. If I change the Bios boot order so that the memory stick takes precedence, I see a dark blue screen announcing Kubukntu 12.04, and on selecting either “live Mode” or “Persistent mode”, messages flash by quickly, some of which appear to be error messages, including “trying to unpack rootfs image as initramfs”, “cannot allocate resource for mainboard”, “no plug and play device found”. Eventually I see a pale blue screen with four moving dots announcing Kubukntu 12.04, similar to the login screen of my Kubuntu desktop, but no invitation to log in or indeed any dialog. After several minutes, this changes to a black screen with more messages including “no caching mode present”, “ADDRCONF(NETDEV_UP): wlan0: link is not ready”, then degrades to a blank pale blue screen which can only be moved by switching the computer off. Finding no way to log the error messages passing by, I managed to photograph most of them, but know no way to attach the photo to this forum. As suggested by User 68186 (to whom thanks!), I have edited my original post to reflect the recent progress, so the following two comments are now superseded.

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  • Lubuntu 12.04 on Acer laptop boots to blank blue screen

    - by WGCman
    My previous question on this was closed, but I am posting it again as the solution which my son eventually found may assist other users of the forum, or someone may be able to tweak the solution to improve the performance. Having installed Kubuntu 12.04.01 from a live USB onto my desktop, I wanted to do the same on my laptop, an Acer Aspire 1362 Laptop, which has 256MB RAM (actually 512 "on the box", but a good deal can be borrowed by the graphics!). I found Kubuntu wouldn't run on so little memory but downloaded: Lubuntu-12.04-alternate-i386.iso, which I understood was light enough to go. The laptop has one internal 40GB Toshiba hard drive divided into 3 partitions: C,19GB with Windows XP, Windows program files and some data, D, 19GB mostly data, and a small 2GB partition with some Acer software, which XP can't normally “see”. I transferred most of the contents of D to a memory stick, leaving 16GB free for Lubuntu. I did not want to dump XP yet, though it is painfully slow. I installed Lubuntu from then USB stick, accepting the default answers to most of the questions. The D: partition was further partitioned into a 500MB boot partition, 10GB for Linux, 2GB Swap and 6GB for data shareable between Linux and Windows. I had no error messages during installation, rebooted, was offered the choice of Ubuntu or XP, and selected the former. After a few minutes, I get a dark blue screen announcing Lubuntu with five dots underneath which lighten in turn. Eventually the lights stopped, and whatever I try the screen remains blank apart from “Lubuntu” I tried several solutions suggested on the forum for “identical” questions but without success.

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  • Creating the “game space” for a 2D game

    - by alJaree
    How does one setup the game space for a game so that obstacles can be spawned? One example I am wondering about is doodle jump. Tile maps are limited in size and would need to change often if the user jumps a lot. How would this be done in another way than tile maps. How or what is used to create the notion of a game world where these spawned ledges/obstacles are placed as the user progresses through the stage? What is actually moving if the user jumps from ledge to ledge, what are the ledges based on in terms of the game world/space. What data structure or representation could the game use to reference and manage the spawning of these obstacles/ledges?

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  • Monitoring Database disk space

    - by Michael Freidgeim
    An article Data files: To Autogrow Or Not To Autogrow? recommends NOT to rely on auto-grow, because it causing delays in unplanned times.We should mtonitor database files(both data and log), and if they close to max capacity, manually increase the size. However it doesn't give references, how to monitor the free space inside databases. I've tried to look how to do it. It can be done manually using   execute sp_spaceused for the database in question or  sp_SOS (can be downloaded from http://searchsqlserver.techtarget.com/tip/Find-size-of-SQL-Server-tables-and-other-objects-with-stored-procedure)Alternatively you can run SQL commands as suggested in Http://www.sqlteam.com/forums/topic.asp?TOPIC_ID=82359 by Michael Valentine Jonesselect [FREE_SPACE_MB] = convert(decimal(12,2),round((a.size-fileproperty(a.name,'SpaceUsed'))/128.000,2)) from dbo.sysfiles aMore useful article Monitor database file sizes with SQL Server Jobs describes how to setup monitoring Finally I found the excellent articleManaging Database Data Usage With Custom Space Alerts, that can be followed even support personnel without much DBA experience.

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  • Atmospheric scattering sky from space artifacts

    - by ollipekka
    I am in the process of implementing atmospheric scattering of a planets from space. I have been using Sean O'Neil's shaders from http://http.developer.nvidia.com/GPUGems2/gpugems2_chapter16.html as a starting point. I have pretty much the same problem related to fCameraAngle except with SkyFromSpace shader as opposed to GroundFromSpace shader as here: http://www.gamedev.net/topic/621187-sean-oneils-atmospheric-scattering/ I get strange artifacts with sky from space shader when not using fCameraAngle = 1 in the inner loop. What is the cause of these artifacts? The artifacts disappear when fCameraAngle is limtied to 1. I also seem to lack the hue that is present in O'Neil's sandbox (http://sponeil.net/downloads.htm) Camera position X=0, Y=0, Z=500. GroundFromSpace on the left, SkyFromSpace on the right. Camera position X=500, Y=500, Z=500. GroundFromSpace on the left, SkyFromSpace on the right. I've found that the camera angle seems to handled very differently depending the source: In the original shaders the camera angle in SkyFromSpaceShader is calculated as: float fCameraAngle = dot(v3Ray, v3SamplePoint) / fHeight; Whereas in ground from space shader the camera angle is calculated as: float fCameraAngle = dot(-v3Ray, v3Pos) / length(v3Pos); However, various sources online tinker with negating the ray. Why is this? Here is a C# Windows.Forms project that demonstrates the problem and that I've used to generate the images: https://github.com/ollipekka/AtmosphericScatteringTest/ Update: I have found out from the ScatterCPU project found on O'Neil's site that the camera ray is negated when the camera is above the point being shaded so that the scattering is calculated from point to the camera. Changing the ray direction indeed does remove artifacts, but introduces other problems as illustrated here: Furthermore, in the ScatterCPU project, O'Neil guards against situations where optical depth for light is less than zero: float fLightDepth = Scale(fLightAngle, fScaleDepth); if (fLightDepth < float.Epsilon) { continue; } As pointed out in the comments, along with these new artifacts this still leaves the question, what is wrong with the images where camera is positioned at 500, 500, 500? It feels like the halo is focused on completely wrong part of the planet. One would expect that the light would be closer to the spot where the sun should hits the planet, rather than where it changes from day to night. The github project has been updated to reflect changes in this update.

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