So I have an animated scene where the camera goes through a window into a house. The only issue is that the ceiling of the house is white (EDIT: it's actually not the ceiling, but the area lamp that's inside — see edit log at the bottom) while the camera looks into it from outside and I have no idea why. On top of that, a character's head is partially cut off, too - only when rendered through the glass.  PROBLEM:    [Rendered looking THROUGH the window]      [Rendered from INSIDE]    SCENE:    [This is what the scene looks like with the window plane hidden via "H"]      [These are the material properties of the glass. It's also been extruded.]      [And these are the materials of the house. Regular image textures UV unwrapped and assigned to the necessary faces.]    RENDER SETTINGS:  GPU rendering Cycles 1080*1920/25 Clamp direct: 1.11 Clamp indirect: 1.17 100 samples Bounces: between 5 and 0; Diffuse: 2; Glossy: 2; Transmission: 12 1/50 motion blur 256*256 spiral  The rest is set to default.    If you have any idea on how to solve this, please share it with me.  EDIT: So I just realised that the whiteness might not be the house itself, but the AREA LAMP that's inside!! And the guy's head is cut off, since that part is in the physical area of the lamp object! Now the only thing I don't know is what to change. If I simply rised the lamp, it would cure the problem with the guy's head, but the whiteness would still be there.  The lamp is - as I already said - an aerial light, its size is 3.433 , max bounces: 1024 , streght: 30
I did setup an easy scene with an area light behind a window. In the glass (simple plane) which is in front the area light is visible - how can I turn this off so that the background is shining throgh?
When speaking precisely or technically, one would say that "Homo erectus and homo sapiens are two species of hominid" rather than "Homo erectus and homo sapiens are two species of hominids." The hominid here should be singular because we are speaking about instances of a single class ("class" being used here in its broader sense, not in the sense of taxonomic grouping).  Now let's consider more common parallel constructions replacing the word species with other words.      Tide and Wisk are two brands of detergent.       Tide and Wisk are two brands of detergents.      Cats and dogs are two types of pet you can buy at Pets-R-Us.       Cats and dogs are two types of pets you can buy at Pets-R-Us.   I feel that using the singular noun to specify the class is more grammatically correct, but sounds stilted in conversation. Almost everyone I hear making these constructions uses the plural form. What are your thoughts about singular vs. plural here?  Edit  Here's a more extreme example that may help clarify the issue. Consider the following sentence:     It was my first attempt at calming an angry crowd, and I just        stood there while people were hurling all kinds of insults at me.   Here I think the singular insult sounds strange, if not downright wrong.  Further Edit  I just noticed in A Treasury for Word Lovers (Morton S. Freeman, 1983) a section entitled "Types of Errors." This is a book about (American) English usage by an English professor and editor, which purports to be a "practical guide for serious writers and readers." I wish I could say this discovery satisfies the question, but in fact I now feel somewhat farther from the truth, if there is any single "truth" in this matter. But at least I don't have to worry about being wrong when using the plural form of the class in these constructions. How can I switch between starting a coroutine vs running the routine all at once? I'm generating a level, and I have an optional delay to show the steps level generation one by one.  If my generationDelay boolean is true, I want to use StartCoroutine to spread the generation out over time. If it's false, I want to call the same method but without StartCoroutine.  The problem is that the method is type IEnumerator.  I can make two methods one type of IEnumerator and one not. But I wonder if there is a way to use one method.  In the first script top i did:  public bool generationDelay = false;   Then in a method:  private void BeginGame()     {         mazeInstance = Instantiate(mazePrefab) as Maze;          if (generationDelay == true)         {             StartCoroutine(mazeInstance.Generate(generationDelay));         }         else         {             mazeInstance.Generate(generationDelay);         }     }   Then the other script where the method Generate is: In the top:  public float generationStepDelay = 0.01f;   Then the method Generate:  public IEnumerator Generate (bool generationDelay) {          if (generationDelay == true)             WaitForSeconds delay = new WaitForSeconds(generationStepDelay);         cells = new MazeCell[size.x, size.z];         List&lt;MazeCell&gt; activeCells = new List&lt;MazeCell&gt;();         DoFirstGenerationStep(activeCells);         while (activeCells.Count &gt; 0) {             yield return delay;             DoNextGenerationStep(activeCells);         }     }   I'm getting an error on the line:   WaitForSeconds delay = new WaitForSeconds(generationStepDelay);      "Embedded statement cannot be a declaration or labeled statement"   And an error on the line:  yield return delay;      "The name 'delay' does not exist in the current context"   The reason I want to use a bool variable is that when i'm using StartCoroutine it's kind of slow, even if I change the value of generationStepDelay to 0 it's kind of slow. And if I'm not using StartCoroutine and not using the Generate method as IEnumerator it will work fast.  So i wonder what should I do and how? Return vs. Enter? I noticed that my MacBook's keyboard has the word enter above the return key. I also noticed that on Mac OS X, there's a special symbol for return ↩, and another for enter ⌤. How would I send the enter key if my MacBook has no numpad?  Is there any difference between these two keys? I tried this:  find . -type f -size 128 -exec mv {} new_dir/  \;   Which didn't work, and it didn't give me an error. Here is an example of what the file looks like, when using stat -x  $ stat -x ./testfile | grep Size    Size: 128          FileType: Regular File I have a vf page that is a custom button. That's it.  this VF page is on a STD Page Layout. When the user clicks on the VF page, the parent window needs to be redirected to the new URL.  The way this is working, is that the new page is opening in the vf section of the page layout.   &lt;apex:page standardController="Opportunity"  standardStylesheets="true" extensions="OpportunityController" &gt; &lt;base target="_parent" /&gt; &lt;body style="background:#f3f3ec" &gt; &lt;apex:form &gt; &lt;center&gt;  &lt;apex:commandButton action="{!redirect}"  value="Change Record Type" rendered="{!render}"/&gt; &lt;/center&gt;   &lt;/apex:form&gt;    &lt;/body&gt; &lt;/apex:page&gt; Is there canon info on shelf life of various potions in Harry Potter? Do we know how long potions (in general, or at least specific ones) are potent (no pun intended) in Harry Potter canon?  E.g. do they last a couple of hours? Minutes? Years?   I seem to vaguely remember some comments of Snape's about Wolfesbane potion therfore I think at least some information exists. What is the best way to store fresh herbs like parsley or cilantro?  I find I have about the same luck with them whether they are left in a plastic bag or I put them in a cup of water. Is it possible to search for punctuation/special characters? I tried to find a related question here, but was unsuccessful.  Someone on SO asked ... I tried searching SO and was presented with the search options page. Even Google fails at this search.  So my question is, is there some way to search for an exact word (in quotes) that won't cause it to fail? What color can lightsabers be? I just saw the fan film  and the Force-sensitive bounty-hunter, Korbain Thor, wielded an ochre lightsaber (or at least that's what  described it as).   I'm just wondering if ochre is a canon color for a lightsaber? What does this box icon represent? Since I started playing, I have seen this icon in the bottom right of my screen. Clicking it does nothing.  What does this icon represent?  I'll add a PC tag, as I'm playing on PC, and it could be related to that. How to properly write multiple authors in bibtex file? I'm reading An Introduction to Manifolds (Tu) and got confused on p.123 Theorem 11.13. Let me briefly explain what was done before that.  The author defines an embedding between two manifolds $f: N\rightarrow M$ as an injective immersion (differential is injective everywhere) with the additional property that $f(N)$ as a subspace of $M$ is homeomorphic via $f$ to $N$. Then a canonical form theorem is proven, namely, that for any point $p \in N$, there are charts $(U,\phi = x^1, \ldots, x^n) \ni p$ and $(V,\psi = y^1, \ldots, y^m) \ni f(p)$, such that the transition map takes the following form:  $$\psi \circ f \circ \phi^{-1} : (r^1,\ldots,r^n) \mapsto (r^1,\ldots,r^n,0,\ldots,0).$$  (I guess it is implicitly assumed that $f(U) \subset V$).  Now in the process of proving that $f(N) \subset M$ is an , he states that $f(U) \subset V$ is defined by the vanishing of the coordinates $y^{n+1},\ldots,y^m$. I can prove that $$ f(U) \subset \{q \in V: y^{n+1}(q) = \cdots = y^m(q)\} $$ but not the reverse inclusion. Can anyone explain why this should be true? Types of circular acceleration? To my knowledge there are three types of acceleration when a body (e.g. a rod) is moving in a circle about an axis. These are:   Angular acceleration : this is the rate of change of angular velocity. Tangential acceleration : this is the linear acceleration of the system in a tangential direction to the circle and equals the radius times the angular acceleration. Radial/centripetal acceleration : this is the linear acceleration of the system that is directed inwards towards the center of the circle.   I also think there are two types of velocity:   Linear velocity: this is its velocity in the tangential direction and is constantly changing Angular velocity or angular frequency: this is the rate of change of angle.   Is the above correct? And have I missed anything? Let's say I have 1m of 2,5mm² copper wire, insulated with H07V-K. The wire carries 40A and environment temperature is 25°C. The wire is suspended in free air. How hot will the wire get? And how can I calculate it for other values?  The use case is a 12V-230V AC converter I want to hook up to my car and determine the minimum wire thickness required. Because it's only used from time to time and not buried in a wall I suspect I can use thinner wires. This is a temporary thing and doesn't need to be up to code. Can I disown my heir? Everything was perfect. I have a good and young ruler, who has passed on some good genes to his sons. I also had a lot of spare lands, so I could make my heir a duke and doubly count when he came of age.  My mistake was to marry him off to some scheming wench. I knew it would end like this, but her stats were just too great to resist!  Anyway, a few years down the road, and my trusty spy master lets me know that my beloved son is looking to usurp me. Not cool! I demand that he end the plot, and decide to see how this develops.  Shortly thereafter, he suddenly dies (not by my hand — likely the wife is the culprit). My second eldest son becomes my new heir and favourite, however all the titles are inherited by my clubfooted grand daughter aged two. Curses!  Now, what I really wanted, was to imprison and disown my traitorous son followed by swift justice of the axe. Not sure what my other vassals would think of that idea, but I had a just reason for imprisonment at least.  Option number two, is to start plotting for my dearly beloved grand daughters untimely demise, but I'm not sure how that would work out either.  The situation is this. I'm young (40ish) and well-liked. I have a new heir, but I'd prefer to keep my lands for myself and give him the ones of the previous heir — one duchy and two counties currently held by my grand daughter. The duchy can be revoked free of charge, as I hold a claim to it. She has no siblings. I am da King. I have limited crown authority, but can bump it up to medium if it suits me.    So my questions to you are as follows:   Is it possible to disown a son, considering I have just cause for imprisonment? An execution would of course settle the deal, but my other vassals would probably find me "cruel". Is it possible to plot against a character which is not yet of age? What would happen if she suddenly died with no heir? Would all her titles be returned to the king or duke (i.e. me)?   EPILOGUE I had savegames before and after, so I decided to test a few things.   I could imprison my quisling of a son. I could also seize all his titles and banish him from my lands, but he would remain an heir, even if he wasn't officially a prince. I guess I could have let him rot in jail, as it seems prisoners often die in custody, but it would be a risky bet. After the unfortunate death of my old heir, it seems some strange rules apply regarding the remaining titles. The dukal title I could simply revoke for free (although at a opinion penalty from the duchess). Should she die today, one of the counties would be inherited by her younger sister, and the other would be inherited by me.   I found this to be an interesting development: Turns out my new heirs wife suddenly died. Who did he marry, other than the same scheming hag who presumably killed off his brother, and made an attempt at me? By a suspicious coincidence, I died not very long after. Such is the effects of the deceitful and ambitious traits combined with a really dope intrigue stat. ;) What is the sign of the work done on the system and by the system? What is the sign of the  done on the system and by the system?  My chemistry book says when work is done on the system, it is positive. When work is done by the system, it is negative.  My physics book says the opposite. It says that when work is done on the system, it is negative. When work is done by the system, it is positive.  Why do they differ? pdflatex bash script to supress all output except error messages? I have a bash script which I use to compile a file with pdflatex twice (to make sure it sorts out references properly, etc.). This is the 'latexbuild' script I use:  module load ctan pdflatex --shell-escape --interaction=nonstopmode $1 bibtex $1 pdflatex --shell-escape --interaction=nonstopmode --interaction=batchmode $1   I would then call this script with latexbuild test.tex. It produces a lot of output which I would like to supress, except for the error messages which I'd like to see. Is there any way to only allow error messages to be displayed? How do I turn off some formats in GeoServer's WMS? I have published a couple of layers on my Geoserver.  To be complaint with the T&amp;C of my data provider, I need to block the access of some of those layers as Vector data. Hence I have already blocked the WFS services on these Layers.  I came to know that even on the WMS service, you can get Vector Data, if you use GeoRSS and some of the .   How do I block GeoRSS, SVG &amp; UTFGrid as formats in the WMS Service? What is the distinction between a professional and amateur photographer? Fingerprint GUI not installing in Ubuntu 20.04 I'm trying to install fingerprint-gui on my Lenovo Ideapad 520 having Ubuntu 20.04 on which fingerprint isn't working for now. I tried going directly to Settings → Users → Automatic login and enabled the fingerprint login, but the error is:  Could not access any fingerprint readers Please contact your system administrator for help!  I also tried to install Fingerprint GUI: sudo apt-add-repository ppa:fingerprint/fingerprint-gui &amp;&amp; sudo apt-get update  sudo apt-get install libbsapi policykit-1-fingerprint-gui fingerprint-gui  but encountered this error: E: Package 'policykit-1-fingerprint-gui' has no installation candidate E: Package 'fingerprint-gui' has no installation candidate  What could be the problem here?