Weird shadow in rendered image Here's the rendered image. The problem is with the shadows on the green object's right side. It's like a weird wave shaped shadow. And I get this result in all my renders where I use subsurf and smooth shading. I don't know if it has anything to do with them. Help if you can, please.  Many thanks  I've tried a few changes based on the two links, but it's still the same. So gandalf3, it's not the same question, the problem is different, as it seems.
Cycles : shadows on smooth shaded mesh, strange behavior I wonder if this is a bug, or if I missed something... When a light hits tangentially convex surfaces with "smooth shading", the shadow on this surface seems to "partially ignore" the smoothness of the surface. Here is an example with a simple cylinder :    On the left, a cylinder with "flat shading". Everything's ok. On the right, the same with "smooth". We can see an edge, bad shadowed.  With or without the "Edge split" modifier, no matters, the edge is still there. The shader is a simple white diffuse shader with no texture nor displace.  I have to add a subsurf modifier with at least 2 levels, which will insanely increase the vertex count... And I can't do that for my project.  I hope someone already saw it, and have a little tip to share. Or if someone already know it's a bug, or a limit of the current Cycles renderer ?
Is there BitTorrent software that runs in a terminal? I want to deploy it on my VPS server to download resources quickly.  This could save me a lot of time since some resources are in a foreign country, How to replace an old version of Ubuntu with a newer one from USB/DVD? I dual booted ubuntu 11.04/11.10 a while ago with a USB stick and i want to uninstall it.   I would like to completely uninstall the old version and get 12.04.  I have a 64 bit laptop. Please help! Is there any way of modifying the preamble, so instead of typing   $\mathtt{x}$ ... \begin{eqnarray}     \mathtt{y} &amp; \mathtt{=} &amp; \mathtt{z^\pi} \end{eqnarray}   I can omit the \mathtt{...} commands? Why only light nuclei are able to undergo nuclear fusion not heavy nuclei? Is it because of the binding energy or the binding energy per nuclei .  I am having trouble with this whole binding energy and nuclear fusion concept. (Up to / until / by) 50% off I wonder if someone could tell me which choice works in the following sentence and why the others do not work: (From my point of view, all of these choices work in this context.)  They have great promotion till January 5th......50% off. a) up to; b) until; c) by How do you prove a number is prime? I am a software engineer but try to keep up with maths as I really enjoyed the subject at school. I just saw a great TED talk:   The talk states that the current largest known prime is $2^{57885161}-1$  This got me thinking - how does one actually prove whether a number this large is prime or not?  Is it just done by brute force via a computer algorithm or are there any well known mathematical techniques for doing so?  I would be really grateful for any pointers as I am eager to learn about these techniques (if they exist). I have a text box that will have a currency string in it that I then need to convert that string to a double to perform some operations on it.   "$1,100.00" → 1100.00  This needs to occur all client side. I have no choice but to leave the currency string as a currency string as input but need to cast/convert it to a double to allow some mathematical operations. Inverse of $f(x)=\sin(x)+x$ What is the inverse of   $$f(x)=\sin(x)+x.$$  I thought about it for a while but I couldn't figure it out and I couldn't find the answer on the internet.  What about  $$f(x)=\sin(a \cdot x)+x$$  where $a$ is a known real constant.  Thank you for taking the time to read this question! Sorry if this has been asked before... I receive the error 'grub-install /dev/sda failed' while attempting to install Ubuntu as the computer's only OS. I am attempting to install Ubuntu on a box which was previously running Windows 7.  I have also experienced the dreaded "Unable to install GRUB" error.  I am not attempting to dual boot. I have previously run a Windows boot disk and removed all existing partitions.  If I run the Ubuntu 12.04 install CD and click install after the config screens, I get the error   Executing 'grub-install /dev/sda' failed. This is a fatal error. (It is the same error as this question: )  All the questions I've read while looking for a solution are related to dual boot.  I'm not interested in dual boot, I'm after a clean out the box Ubuntu install. How can I achieve this?  (For my sanity, please use very simple instructions when responding. I don't claim to have any talent either for linux or as a sysadmin)    Additional details copied from comments dated: 2012-05-29 ~15:19Z  After booting from the CD, clicking Try Ubuntu, and then sudo fdisk /dev/sda I get fdisk: unable to seek on /dev/sda: Invalid argument  sudo fdisk /dev/sdb gives   Device contains neither a valid DOS partiion table, nor Sun, SGI or OSF disklabel.  Building a new DOS disklabel with disk identifier 0x15228d1d.  Changes will remain in memory only until you decide to write them.  After that of course, the previous content won't be recoverable.  Warning: invalid flag 0x0000 of partition table 4 will be corrected by w(rite).  Command (m for help):   I should add the Live CD desktop is graphically bad. I've got missing parts of programs and the terminal occasionally reflects to the bottom of the screen. But I can't imagine this is related. How to find a function in $ L_{2}(0,\infty)$ but not $L_{q}(0,\infty)$, $q\neq 2 $ I have had no problems exporting .fbx files for Unity except recently some of my .fbx started to rotate the mesh. The asset is correctly oriented, but the mesh is rotated 90 degrees. Is there an explanation and fix for why this happens sometimes, and works properly otherwise? How to shift EXIF date/time created by time in days, hours, minutes? I have two camera bodies, I was shooting while on vacation, when I downloaded the photos to lightroom, one body was set to the correct date/time, the other was off by 722 days, 4 hours, 32 minutes.  Is there a tool available that can help me fix the date/time so that they appear in sequence while browsing my lightroom library?  I'd like for them to be as close to the right time.     I was able to adjust created year, month, date, but it doesn't appear lightroom will allow me to adjust increments (only hour increments).  Many thanks if you can help me in this task! Selecting attribute values with html Agility Pack I'm trying to retrieve a specific image from a html document, using html agility pack and this xpath:  //div[@id='topslot']/a/img/@src   As far as I can see, it finds the src-attribute, but it returns the img-tag. Why is that?  I would expect the InnerHtml/InnerText or something to be set, but both are empty strings. OuterHtml is set to the complete img-tag.  Are there any documentation for Html Agility Pack? PHP class: Global variable as property in class Deleting polygon defined area from raster layer in ArcGIS Desktop? Which tool do I use in ArcGIS 10.1 for Desktop to exclude areas covered by vector polygon layers from a raster layer?   I want to keep portions of the raster layers that exclude the portions covered by the vector layer. Trying to find a TV show about an event that leaves everyone dead apart from people who died at the moment of the event? This was a TV show aired in the UK probably sometime between 1990 and 1993, if memory serves it was only a one-off. The plot starts with the protagonist waking up in bed and being disappointed. He eventually goes outside and everyone is dead, whatever they were doing at the time they died doing it (driving, working, etc.) The protagonist is in a state of panic running around town (I seem to remember it being set in the UK) and he discovers that he's is 'alive' because he'd attempted suicide and died at the exact moment this mysterious event happened. I think he encounters others that 'died' at the time of the event and that's when he realises. I think the protagonist was a bald, white man, probably mid-thirties. Sorry for any vagaries, I was VERY young when it was on. Until recently I assumed it was The Quiet Earth but I've checked and it definitely isn't. It was in colour and was contemporary at the time so it would have been made around 1990. What to do when visa admission expires during lockdown? How can I suppress all output from a command using Bash? I have a Bash script that runs a program with parameters.  That program outputs some status (doing this, doing that...). There isn't any option for this program to be quiet. How can I prevent the script from displaying anything?  I am looking for something like Windows' . With no good reason I had a look at my computer's storage going on the apple and About this Mac. Here is the display:    The pink bar doesn't make much sense. It obviously does not represent the 80.67GB of free storage. Two sections correspond to pink; "Photos" and "Backups". I obviously don't have 140.76TB of backups. And probably not on this computer that has only 320GB of storage.  What is going on here? Kernel requires an x86-64 CPU, but only detected an i686 CPU. How can I install Lubuntu/Ubuntu?