text:
How do I adjust for overexposure using physically based lighting?
I am trying to get my head around physically based lighting in Blender.
I read somewhere the Cycles Sun Lamp is measured in W/m² so
assuming that bright sunlight is measured at 120000 lux (https://en.wikipedia.org/wiki/Daylight) my intensitiy for the blender sun will be (given that 1lux = 0.0079 W/m2 for sunlight) around 980 W/m². This matches more or less with the readings from wikipedia, that states that the max sun intensity depending on its distance from the earth is 1050 W/m² (https://en.wikipedia.org/wiki/Sunlight).
Using the filmic Blender add-on I am now way overexposed.
Here comes my first question: where do I compensate for that? I found two exposure sliders within Blender. One directly in the color management tab, which I assume doesn't affect the final rendering, but only the viewport lut. Or do I use the exposure slider under the render tab/film?
Second: How does cycles handle the light contribution from environment maps? In what relation do they stand to the sun intensity as they have a seperate intensity slider. Is there a rule of thumb to get them in the right ballpark?

Please only ask one question per post. You are welcome to ask as many separate questions as you need as separate posts.


text:
Game Engine - Actions dependent on an integer
I'm attempting to put together a turn based combat system that requires the game engine to look at an integer titled Speed to dictate which character goes first. The problem I'm having is how do I have it send a message to specific actor based on speed?
So far I have it set up in my head as:
Empty Object copies Speed integer from both characters
After Confirmation of action, message sent to Empty Object
Empty Object compares Player 1 speed and Player 2 speed
This is part I have trouble with. How do I have it send the attack message to the one with the higher speed then AFTER the first one attacks, send a second message to the remaining player?

Empty Object Receives Speed integer from Objects named P1 and P2
1.[Set to Tap]Message"Confirmed Attack"~P1S>P2S~Message sent "P1S Attack"/Property Integer "P1S" set to 0
2.[Set to Tap]Message"Confirmed Attack"~P2S>P1S~Message sent "P2S Attack"/Property Integer "P2S" set to 0
3.[Set to Tap]Message"Confirmed Attack"~P1S=0 AND P2S=0~Property Copy "P1S Speed" from P1 Object/Property Copy"P2S Speed" from P2 Object
4.[Set to Tap]Message"P1S Attack"/Message"Delay P1S Attack"~AND ~Delay 50 Logic Ticks
5.[Set to Tap]Message"P2S Attack"/Message"Delay P2S Attack"~AND ~Delay 50 Logic Ticks

It took a lot of characters to make that and I had to delete spaces so I apologize for how tight nit it is. You can see where it says 1. and 2. and 3. and so on. Those are basically to dictate each logic brick. it's just it got smashed together like that and not spaced paragraph like I had it. Essentially the player objects will send the delay message so that a delay happens to allow time for actions to complete before the logic bricks continue.

So now comes the question. Will this work essentially for my original problem?

source: Stack Exchange

license: Creative Commons - Attribution Share-Alike - https://creativecommons.org/licenses/by-sa/4.0/

sort: votes


text:
Blender for Chromebook
How would I be able to run Blender on a Chromebook? The Rollapp is a farce that demands money for free software, and the whole reason I didn't buy a windows laptop is because I hate Windows 10, so is there another option?

I hear Chromebooks will soon support regular Linux apps, if they don't already, which might help there. But I think this question is off topic here.

https://www.androidpolice.com/2018/08/19/install-linux-applications-chrome-os/ ... all You need to know buddy.

has anyone actually done this successfully?

@pluke yes.  I replied with an answer below.  Works for me just fine.

great! I'll give it a go

First off, don't use a chromebook; most are too underpowered for blender. get a laptop that's actually capable. system76 should fit your needs right off the bat : https://system76.com/laptops | but I recommend finding a cheaper alternative and install a Linux distro to it (Manjaro,Pop_OS!,Solus,Debian,Ubuntu,ect.).

If you hate Windows 10, there are other options. I know you asked about Blender on Chromebook, but you can find non-Windows 10 computers for very cheap or free. I got a desktop with Linux from my local library, and my tech teacher gave me a Windows 7 laptop for free. Try asking around.

IMO Chromebook is a good alternative to a linux laptop (even though it's still in beta).  ChromeOS does a lot of the heavy lifting for you and you get the benefit of linux apps and terminal.  I've posted an alternative answer if you want to critique the steps I used to install blender on my chromebook.

I just bought a chromebook and was interested in this very topic.  I've compiled the correct steps from this link as well as some basic exploration.

Hit the Launch button (key with a small circle on the left side of the keyboard where caps-lock is on other keyboards) and type "terminal".  I was prompted to accept the linux install and I did.
Update packages (this had a couple of errors when I ran it that I ignored.. I think the failures are updated by chrome OS in the background in its distro that it maintains for you).

$ sudo apt-get update && sudo apt-get upgrade

Install gnome and update it with these commands

$ sudo apt-get install gnome-software gnome-packagekit -y
$ sudo apt-get upgrade -y

Restart your Chromebook
Hit the Launch button again, and search for "Software" and open it.
Search for blender, then install it.

It should now appear in your Launch menu alongside your other apps.  Gnome also gives you a launch button when it's finished installing.

What version of blender is this?

The .79 release for me. Not sure when the linked apt-get source will update to use the .8* versions

The repos seem very slow at keeping up to date. It's be interesting to see which chrome books can handle the higher spec requirements

I am pretty sure you can get Linux on chromebooks, but to install Blender I think you can check how to install it on Linux
https://support.google.com/chromebook/answer/9145439?hl=en

If you're going MAC, make sure you get a newer model. Several years ago, my Dad got an all in one iMac with a decent Nvidia Card, which he recently learned is nearly useless. How? Apple dropped Cuda Support. Just wanted to warn you guys.
I recommend checking out Concierge Render by Coreweave. It's a large render farm for Blender projects, available to the public. It can run images and animations in 2.79, 2.8 and 2.81 Cycles and Eevee in 2.81. Using it costs as low as 30 cents per gpu per hour, and you get $5 credit just for signing up.

instead of using windows or Chromebook you could use Mac especially because they are built to be able to render the product.

Mac platform is often regarded as over priced, and it is a particularly poor choice for 3D modelling and rendering especially with Blender

all_licenses: Creative Commons - Attribution Share-Alike - https://creativecommons.org/licenses/by-sa/4.0/


text:
Union acts like difference
I stuck on this problem for a while and I have tried some solutions like remove doubles, check normal and i'm sure all the normals are facing outside... but after I done these, it still cannot union.
here is the file:https://www.dropbox.com/s/pu5zmob86w4rzwb/retopo.blend?dl=0
this is what I have:

and after I hit the union button from "Blender-Sculpt-Tools", it becomes this:

also I have tried to add the boolean modifier directly, but it shows like this, lots of dots and the head just gone. btw, i use join on head and body before, will this be the problem? but how do I separate them and use union instead of join?

Hi, be sure to check also possible negative scaling. This happens sometimes, and make reversed normals look correct. I would check your example file, but over 110MB is too much for me, just to check.

@m.ardito I checked the scaling, they are all good, but I found one of the rotation is set to -0, after I changing that, it still cannot union, so I think that's not a problem... i have already check the normals, I hit ctrl n on all the faces...

The hair mesh is a non-manifold geometry, that always causing boolean operations, make sure that the hair mesh is solid, or at least move all the non manifold geometry of the hair inside the head mesh, so that there are no holes.

@Denis Thank you so much!! I found the broken face on the hair mesh, after re-sculpting that, the problem is fixed


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Character physics "jump limit" in bge....!
So, I'm trying to make a flappy bird -like game and I'm using the "character physics" to make the bird fly/jump but the limit is 225 jumps...
Any solution to exceed this limit?
I'm relatively new to bge

Can you provide a screenshot of your character logic?

There is no easy way to do this. Even though there is a jumpCount property you can not edit it via script as it's readable only. However, after some tests I found a hacky workaround that might do it for you, because resetting the gravity seems to reset the jumpCounter. It can by achieved by this procedure:
Paste this script into the text editor.
import bge

def main():
    cont = bge.logic.getCurrentController()
    own = cont.owner
    hero = bge.constraints.getCharacter(own)
    hero.jump()

    # Reset the gravity:
    hero.gravity = 0
    hero.gravity = 30 #default value. You might change this :)
main()

Then use the following setup on your player to trigger the script. Notice that the jumping is also done via the script.


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Is it bad to stretch/rotate your quads?
I am currently learning how to model (fresh noobie here). To do this I am undergoing a project that is way over my head: Modelling a female body (I removed all nudity from images in this post).
I making progress; however, I have noticed one major difference between my model and an incomplete model from an cancelled tutorial. (Unfortunately I only learned it was cancelled several hours into it XD).
If we look at the most up to date version of the model from the tutorial, you can a lot of squares that seem to avoid rotating or stretching. They are, for the most part, all in similar size and aligned rather straightly on the various axises. There are exception of course for the more unique areas, like the shoulders.

Now if we look at my model...
I ended using a lot more curving and rotated my quads. I don't really have similar sized quads throughout the entire model and a lot of them rotate a fair ways which dis-aligns them with the various axises. While my model is still incomplete, I felt like that area was pretty close to completion.
I ended doing this because I felt like it followed a better flow with the female body. In the particular area of my screenshot I thought it goes better to define the bones at the top of the waists. See the screenshot at the bottom for a visual reference.

Is there a particular reason why the modeler from the tutorial might want to emphasize on the similar sized quads and not rotating the quads as much? Or is it just an individual modeler's preference?
Is there any "bad practice" views on how I've been making my model?
I am NOT looking for opinion/preference based views. I am looking for answers that are backed up by generally accepted "good practices" and "bad practices".

Faces are generally shaded better if the quads are less distorted. They are also better for subsurf and animation. Best practise would be avoiding distortion (parallelogram shape) but not rotation.
Take a look at "face topology". I find it very helpful to get an idea how to approximate a surface with quads best as possible.

That makes a lot of sense. :) Essentially if I made my quads were more similar size it would be better... Might be hard to fill in the space on the outer waist due to the smaller space in the inner waist/thighs though... Thanks for the input. Going to wait and see for some other answers before I mark yours as the accepted answer.

license: Creative Commons - Attribution Share-Alike - https://creativecommons.org/licenses/by-sa/3.0/


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Car python script stopped working when I edited part of the moldel
I recently used a car python script and tweaked it to work, but as soon as I edited the front part of the car, it stopped working. there is a working car in the blend file attached.
https://drive.google.com/file/d/0B8TTcNitjst6dVV1LWllU1drZmM/view?usp=sharing

Please use https://blend-exchange.giantcowfilms.com/ for future blend uploads for more permanent hosting.

I assume you are using the blender game engine?

yes I am using the BGE

Nvm I figured out the problem. I checked the other car and realized I didn't connect a logic circuit to the visibility blocks of the wheels.

all_licenses: Creative Commons - Attribution Share-Alike - https://creativecommons.org/licenses/by-sa/3.0/


text:
Switch from Multitexture to GLSL BGE
I would like to switch from Multitexture to GLSL mode in the Blender Game engine (unless shadows work in Multitexture), but I do not know the process. simply switching the button causes a full white screen. Help?

You can press N to show the side panel an change from multi texture to gls.

If the image still white change the viewport shading shortcut Z to material or texture.

it render the objects, however all textures are solid white

when i turn on the matcap option I get a similar effect but in the 3d editor (solid mode)

you have to set gls as first img and material as second img. i tested with your blend and it works... what are you asking??

thx it works great


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How do I link Particle data between objects?
Normally if I have a material and want to put that material on say, 50 different objects, then I would select one object with that material, and then select the rest of the objects, hit Ctrl + L, and the material data would be copied to all the objects.
I have the exact situation I described above, except that I want to copy an object constraint from one object to all the other objects. Unfortunately the Ctrl + L menu doesn't have a "Particle" button.
How do I copy this Part to all the other objects?

select all the objects you want the particle system to be linked to
select the object with particle system as last (so it is the active object)
from particle system list select the system to be linked (the active one or all the particle systems)

It basically is just linking the modifier.
Here is the steps in Blender 2.79b:

Select object that you want the particle to be linked to.
Select the object with particle.
Hit Ctrl + L on your keyboard.
Select Modifier.


text:
Moving a bone moves only the first level of child, not all levels of children
I have a cylinder, with a child piston coming off it. I made the piston by following this tutorial. The piston is stuck to the cylinder by making one of the "bearings" at the end of the cylinder into a child.
When I move the cylinder around in edit mode, the piston moves with it, which is what I want to happen.
I am trying to rig some bones up for this, and I have put a bone and set the cylinders parent to be the bone. When I move the bone in pose mode, the cylinder moves, but the piston does not. I rigged the cylinder to the bone by selecting "Armiture Deform -> With automatic weights". I tried to set it as a bone, but it teleports the cylinder somewhere else. No idea what is up with that.
Why does the piston not move with the cylinder when I am moving the bone? How can I make the piston move with the bone in pose mode?

You used automatic weights?  Click the cylinder and go to weight paint mode.
On the right side under Vertex Groups click on the bone in question. You will probably see that the cylinder is red and (depending on how many bones it has) green. But the piston is probably blue. There are two ways to fix this. You can extrude your current bone(s) so that you have a bone for the piston and then re-parent it with automatic weights. Or you could select the piston, in edit mode select all of the faces of the piston. Then find Vertex Groups on the right side of the screen. Click on the bone that you want the piston to move with. Make sure you are using a weight of 1.000 and then click assign.
Hope that this helps!

Your Welcome!!!


text:
Can you change the sampling settings per object?
I am wondering if it's possible to change the sampling or otherwise the render quality per object in a scene.
The use case is if I know an object will appear essentially the same with lower sampling quality, but other parts of the scene will take higher sampling to look good.
Example:
I have a cloud object on the left side of the scene, requiring volumetric calculation, greatly increasing the amount of render time for the whole scene. On the right side of the scene, there is a simple box with a diffuse shader, requiring no volumetric calculations. So because of the cloud, the whole scene takes much longer even though it's the only thing requiring extra calculations.
I supposed the current solution would be to render the parts separately (left, then right), then stitch them together in PS, but I'm hoping there's a better way to do it more selectively and precisely and within Blender.

I think the answer is no. It doesn't really make sense to set the sampling amount per object, since light paths need to be calculated using your entire scene for reflections, etc.

@person132 I can understand how it would not be used too often, but I think it would still be useful in some edge cases. If you have a mirror-like shader and a simple diffuse shader, you might want like 4 or 5 (or more) glossy samples for the first to look good, whereas the other just needs diffuse samples, no glossy. It would save a lot of time I think. Maybe by shader instead of by object?

I agree there might be situations in which it would be useful, but I don't think it is a feature blender supports.


text:
Rising Buildings Animation
I need some help. I am looking for the easiest way to create the animation of a few rising buildings. The idea is to start the animation with a natural landscape and then to make appear from nowhere 5 simple high rising buildings that grow till hiding the beautiful natural landscape.
My problems are essentially two:

how to make the first basement appear from the nowhere, as it seems to me that I can't add a keyframe when there is no object, a part from the landscape;
how to make the buildings grow one after the other but, at the same time, separately; I try to explain: I have tried to copy and paste upwards the first floor to create the top floors of the first building and then do the same in other positions of the plane for the other buildings. But when I animate, the floors of the other buildings seem to shift from the first one, as if the animation recorded not just the new rising buildings, but also the movement of the copied floor, from the original building to the others.

I don't know if I have been clear enough. I have looked for a video tutorial for days, but without any result.
I am really a first-time blender user and I am doing this project for a university examination, so I hope somebody could help me.
Thank you a million for any advice.
Enrico

did you try to animate the build modifier...? or if building blocks are each a different object you could animate renderability (camera icon in outliner)... even animating the array modifier could turn useful..

Thank you very much for your answer! I will try and see what happens!

As to the first question: I think toggling the "restrict rendering" button using keyframes should allow you to make the object appear seemingly from nowhere.  The object is there in all frames, but it is not rendered until the frame where you turn rendering on.
I am assuming you know how to insert keyframes (hover over the control on the frame you want, set to the value you want, and type "I")


text:
Error when Adding a Python Script to a Driver
I seem to have a bit of a problem that I was wondering if someone could help me with.  As the title says, for some reason I keep getting an error when I try to add my script to the driver, and I can’t seem to figure out why at all. Here is the screenshot of how I’m applying it to the driver:

and here is the code:
import bpy
import math

def ShiftMoonMonth(objectName):
    obj = bpy.data.objects[objectName]
    sourceRotation = obj.rotation_euler.z
    finalRotation = (math.floor(sourceRotation/389.10)*29.10564039280042)
    return finalRotation

bpy.app.driver_namespace['ShiftMoonMonth'] = ShiftMoonMonth

I have auto-run python scripts turned on, and when I look through the available namespaces in the blender console, ShiftMoonMonth is one of the options I can use.  So I’m pretty sure that the code is linked to the driver, but for some reason it’s still giving this error.
The place I got the code template from was this tutorial here: https://youtu.be/rfEFU0Mdq3Q?t=21m50s at 21:50, where he is trying to solve a very similar problem to what I’m solving.  As far as I can tell, it seems to be the same as what I have, although it is quite old, so there may be something else you have to do. I also don’t understand the language, so I may have missed something.
Anyway, any help would be very appreciated!

For a single property type driver variable you need also to set the path value.  For example

import bpy

def x(name):
    print(name)
    return 0

bpy.app.driver_namespace["x"] = x

for example shown prints "Lamp", the name of the lamp object, to the console.  Ok, string properties can be passed via driver variables.  (personally don't recommend it) (note also for this case, the expression could simply be x("Lamp") with no need for a driver variable)
Not setting path for the single property driver variable will result in "None" being printed to console.
Ok, now that we know a name can be passed, it's best to check for errors with something like,
if name is None:
    print("problem with name variable")
    return 0

obj = bpy.context.scene.objects.get(name)

if obj is None:
    print("no object named:", name)
    return 0

as errors will mark the driver as "bad" which can result it in being turned off.
A more usual way would be, where the x Euler rotation of the Lamp object, is passed as a float variable, "var", to the expression floor(2 * var / pi).

PS also of note is that rotation in blender is in radians.

You're using an object reference, but your code expects a name.
You may want to use rotation_euler as data path setting, and use that as parameter value. It'll make your code easier (and probably solves this problem).
It also avoids accessing objects by name; name based access is usually a bad idea, since names are not unique. Objects linked from other blend files may have the same name.

(I had to put this here to have enough characters to reply)
Ah, I see now.  bpy.data.objects[ ] is looking for the name of an object, and if I had gone the next step and set the Driver’s Data Path to rotation_euler, I would have been trying to pass the rotation into it when it was looking for the name.  The reason it was giving the error was that it didn’t have any name being passed into it.
To help out anyone in the future, here is the way it’s set up so that it works:

and how the working code looks with the object reference omitted:
import bpy
import math

def ShiftMoonMonth(valueToGet):
    #obj = bpy.data.objects[objectName]
    #sourceRotation = obj.rotation_euler.z
    finalRotation = (math.floor(valueToGet/389.10)*29.10564039280042)
    return finalRotation

bpy.app.driver_namespace['ShiftMoonMonth'] = ShiftMoonMonth

That’s great to know that just adding floor to the expression area works as well, batFINGER.  I had thought I would need to import the math library to get it to work, which is why I went the script route in the first place.
Thanks for the tip of using radians, too.  That would have been very difficult trying to figure out why the calculations weren’t working with degrees.  Everything is working perfectly now. :)
Thanks so much to you both for taking the time to answer it!
Is there a way to mark both of your answers as correct, or do I need to choose just one?


text:
How to unwrap a 1:1 Ratio UV Map?
I am trying to unwrap my model (simple cube) but I don't want the
traditional "Smart UV Project" unwrap.

I'd rather much want it to unwrap like so. (Done manually)

(Reason why is because I use a single texture for my model, for simplicity
and I want it to be a 1:1 ratio in the scale of things, I also Mark all the seams for each "flat surface", so a wall with a hole in it, would be one surface, if there's a slope, that slope becomes it's own "surface")
Thanks in advance

Had you solve it?

try this:
mark those edges as "seams":

then  a simple UV unwrap gives:

You must've misunderstood, problably didn't ask properly. I want the Unwrap to scale accordingly to what the size of the model itself is. So if a wall on my model is 8 "units" long, I want the Unwrap to be 8 units long, OUTSIDE the initial area https://i.imgur.com/bXmBorV.png

This is after I did everything manually. https://i.imgur.com/Zw1eyY4.png  The square bottom left is the 0 to 1 UV "area", I want the UV "squares" to scale from 0 to 1 according to how large they really are, if possible even without doing it manually.

You can do it with "Magic UV" add-on.
The functionality can be found under "Manual Word Scale UV"

You have to set scale equal to size of the texture.


text:
Scaling bone multiplies texture
I followed this tutorial:
https://youtu.be/kB9cJ3wOoPk?t=1039
When I try to scale the bone to make the eye smaller the texture multiplies as shown here:

your mesh: https://blend-exchange.giantcowfilms.com/b/A8nlzxEe/ there's a UVWarp on the eye mesh, I don't know how you can avoid the image to be repeated, I don't know enough

It's all good my guy

you could simply rework your image so that you have a large margin of white, it would be another way around, not sure you can fix your problem otherwise  ;)

I would just add regular UV map to the eye mesh for eye rest pose. Then create en empty object controller to it. Add UVTransform modifier with an empty controlling it. Animate empty to scale/move the eye.

@moonboots You legend thanks to your idea I got it working! :) The other one from D. Skarn was a bit too confusing for me

Your eye mesh has a UVWarp modifier. I don't know how to fix your problem with the current image, but another way around is to rework this image so that you have enough margin of white.

It didn't work, the first picture is the bottom two extended and the 2nd one is all extended https://imgur.com/a/xDw42sO

please share your file (only the eyes, make sure that you've packed its image): https://blend-exchange.giantcowfilms.com/

Sorry, I didn't realize you said just eyes.


text:
What are good free PBR material libraries for a beginner?
I'm in the process of figuring out blender (on what could be considered my 3rd project I guess), and while browsing tutorials and youtube videos about blender, I've come across the topic of PBR materials, and have found it intriguing. I've found that using these materials makes my renders look a whole lot better than if I just slap a flat texture on the objects, but I'm a student and don't want to be spending money on this hobby just yet, which has run me into the issue that there aren't a whole lot of these materials out there that aren't reserved for some payed service. Do any of you know of any material libraries out there with PBR materials for free? So far I've been using the free materials on poliigon, and came across freepbr.com, but I can't figure out how to download any of the textures/maps from the latter of those two.
Any help is appreciated!
Thanks,
Ethan


text:
Uploading to Sketchfab loses texture
I am trying to upload a model to Sketchfab and I always lose the texture.  I have tried uploading a .blend file directly, as well as exporting to .OBJ and uploading to that.  In both cases, the model is not maintaining the texture / coloring.
Any idea what I might be doing wrong?
Thanks in advance.
Edward

I believe that's how Sketchfab works -- the model comes in without the texture and you have to add it back in manually within Sketchfab's interface. Of course, if you're using a Cycles procedural material, that will be lost as well and you'll have to try and replicate it within Sketchfab.

My mistake.  When exporting from Blender I should have set it to copy the texture file instead of using the default setting "Auto".  I thought I had done this, but when I restarted from scratch I saw that everything now worked - when I did things correctly.

where can i set this setting?


text:
How Can I Control The Normal Pass In The Compositor
I am trying to change the bump value inside the Compositor just like the other pass,like Direct indirect color glossy diffuse.
i search on the manual i did not find how u combine  all pass with the Normal pass
can some one help understand how i can use the Normal pass and what is it for ?

If you want to modify the bump or normal map you would do that for the material and not in the compositor. The normal pass is part of the data passes, not lighting passes and therefore it's not part of the image construction as depicted in the manual (https://docs.blender.org/manual/en/latest/render/layers/passes.html?highlight=pass#combining).

thank you so much for clearing  this up


text:
Why are my preview renders good and my actual renders totally black
I'm using Blender 2.79 and Cycles renderer.
Can't figure out why my pre view renders look like this

and my "rendered" images look like this.

Only a total noob to blender.  Have been using Modo, Max and Lightwave for about 15 years.
I've seen Render Layers as a common problem.  i don't think that is my issue

Thanks for the help

Add screenshot of outliner, or post blend-file

Bit of a noob myself but do you have a camera in the scene and more importantly is it checked to render?

Thanks for the responses.  None of those things seem to the be the issue.  If anyone has the time to check out the blend file that would be awesome.         https://wetransfer.com/downloads/db3c95b4b577be2f51d4013ee47d523a20180202053201/79c70146860f04f987218daf3d9cd57c20180202053201/6fa110

Sorry... I'm an idiot.  In case there is anybody else out there who might benefit from this.  I decided not to render the window panes and so i didn't make them transparent and I clicked the little eye icon to hide it in the 3D view.  So when you do a preview render in cycles it gives you a preview of what is visible in the 3D view.  However hiding something in 3D view doesn't mean that it won't render.  So my non transparent windows that were hidden in the 3D view were blocking the sunlight from coming into the room.  Lesson of the story is hit the little camera icon next to an object in the Outliner to make it invisible to the rendering engine.
Thanks again for the responses.


text:
Cross section using Camera Clipping Distance results in very dark model interior
New to BSE; new to Blender.
I've imported a fairly complicated .stp model into Blender and successfully produced some renders using Cycles.
Now I want to produce a cross section of the model to show the detail inside. In the viewport I'm achieving what I want using the Camera Clipping Distance.
Viewport:

When I render the scene, using Cycles, the interior parts which are exposed by the clipping distance are extremely dark, i.e. black.
Render:

I have a sun and couple of hemi lights outside the model. I tried moving a light inside the model but it didn't seem to change anything.
Can anyone help me how to avoid this or how to light the scene correctly.
Thanks!

There is no light inside your objects so they are naturally dark, clipping doesn't change that. Sunlight is always calculated as if at an infinite distance, putting it inside an object is indifferent.

What Duarte said, you'll need to cut that pipe in half so light can reach the inside, clipping doesn't affect light rays. I guess you could put a spotlight or an emitter of sorts inside the pipe but that will get messy fast.

If you need to render an effect like this, it is recommended to use a boolean as that will actually affect the final rendered mesh, not just visibility to the camera.

Make sure light can reach the interior. Use boolean modifier(s) to effectively cut away portions of your model, thus giving a true cross-section.
Example:

Create a new mesh (e.g. cube).
Add a boolean modifier to object which you want to cut away. Set
mode "Difference". Don't hit apply.
Make the new mesh (1.) the target for the modifier.
Move the mesh into desired position. Where the mesh overlaps the
object will be cut away.


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X and Y axis off
I create an object, from other object face. When moving it, I noticed that the movement is not correct on X and Y. I turned on axis, and I see that they are completely off. How did that happened and how can it be fixed?

I suppose the object has been rotated in edit mode.
A possibility to fix it is to use a new feature in 2.8: manipulating the object origin only.
To enable this option, use:

Then to fix the axis alignment, set snapping on to edge for move and rotate:

So you can move and rotate the axis to realign it to your mesh:

You can now desactivate the option that afects only the origin.
And use AltR to realign the entire object to the global axis.

Maybe you're looking for "local" orientations, instead of global.
If this does not resolve the problem, probably you have rotated the vertices in edit mode, so you have to create your own custom coordinate system: in edit mode select a face, then press the plus icon near the list of the transform orientations. Give it a name and use it for your transforms.

I did that, it does not change, stays the same.

I updated my answer.


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Fluid is not generated
Following few videos on youtube, I try to create a very simple fluid animation:

Creating a cube for domain
Creating a circle and change Fill Type to Triangle fan.
Placing circle inside the cube
In physics tab while circle selected creating Inflow fluid
In physics tab while cube is selected creating Domain fluid

Clicking on Bake button and as result nothing happens. I see progress bar working up to 100% without giving any error but there is no fluid simulation.
If I change circle to other type of geometry - it work. I want to use the circle to generate a water flow as it is coming from pipe.
I am using 2.78c version

Thanks for reply. When I add thickness the container is generating fluid in shape and volume of inflow object and this is not what I want to achieve. I want to generate effect as water streaming from a pipe.

I have had a similar problem. My fix was to make the pipe after I simulated the fluid. This works pretty realistically. Hope this works for you!


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Breaking object into parts
I have a model of piano that I would like to 3D print.
The model comes as one part like in a picture below:
I would like to print it in different parts like this:

Is there a way in Blender (plugin maybe) to create sort of joints (in a parts marked as red) so I can easily attach them after printing or this is something that needs to be done manually?

I don't think there are plugins... there are way too many joins that it would have to cover. You'll probably have to do it yourself. I can write an answer showing how if you would like.

Thanks, I know how. Just wondered if it can be done automatically

What format is the model in? What about quads or mesh?
Quick answer is you could boolean a big box to cut the pieces off.


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Weird shapes and lines on solid shapes and low light on cycles
I'm new to blender and I have been using blender cycles the lighting is weird and low in my render and another issue is that my shaped are glitching out and showing random lines and shapes on solid objects. I thought It was connecting all vertices but I tested it by remaking the object but no luck.

Please clarify what you mean, it is not clear what the issue is, and please keep only one question per post, if you have multiple problems post them separately.

From your picture, the shape glitching looks like Z-fighting. This happens when you have two objects (or faces of the same object) that occupy the same space. If it is Z-fighting, it will probably flicker when you move around in the viewport.
To fix it, try moving the object around. You can also try going into Edit mode, selecting all the vertices, and pressing W > Remove Doubles. (This is also good to do just on general principle—even just canceling a Shift+D will create duplicate vertices in the same spot.)
I don't know about the lighting issue; can you post a picture of the rendered view so I can see what it looks like?

The lines are coming because of the scene clipping value maybe.You can change it here:
Generally it should be 10cm and 100km then it should work fine and for the low lighting maybe you can change it in world settings.

Each scene may need its own values for clipping, but 10 cm for low clipping and 100 km for high are crazy values for probably any scene out there. It's also not clear how is the world lighting related to clipping in the scene.

but those clipping values might solve the problem and the world lighting is not for clipping,its for the low light in the scene which is asked to be corrected in the question.


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Multiple textures for one mesh
Okay so I am converting items for my own personal game play.The platform i use for my game requires one texture only but the items that I am converting has up to three or four different textures and come in as separate meshes. My goal is to have one item with the textures merged to fit into the merged mesh. I already know how to join the meshes I just need to know how to get the textures to align with the mesh.

It's not clear how you are using Blender here.

i have the item opened up in blender it has all the textures attached i want to merge the textures into one so i can extract the uv map

Look for texture baking. If you are using cycles: https://blender.stackexchange.com/questions/13508/how-do-i-bake-a-texture-using-cycles-bake/13509#13509

Add a new UV set in the Properties panel , and unwrap the mesh in Edit mode using that UV set. Open a new image texture in the UV Image Editor at the size you want the final to be, and in the Render tab of the Proiperties panel, open up the Bake tab. Select 'Textures' and then press 'Bake', and you should see your existing textures from the object appear in the new image. Save it, and then set it in the material's texture stack for actual use.

how do you add the new uv set? lol

see the edit above - in the properties panel, and you can add a new uv map.

i got all the other steps just didn't get what you meant by set it in the material's texture stack

"Texture Stack" is how I refer to the Texture Slots when looking at them in the material shader tab in the Properties panel. Some people will assume that the image is already in the material after baking, but you must manually add it to the material after saving the baked image.

found materials in the properties menu just need to to know how I would add the materials in manually and I am one of those that assumed the material would have been ready lol


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Python set active face/batch unwrap Follow Active Quads
TL;DR: How do I set a bmesh face as active through Python?
Long Version: I got this random pre-made complex mesh of a tree, it is well modeled, but it came with garbled UV coordinates, without properly unwrapping it, it is pretty much useless.
Manually unwrapping seems out of the question (too many hundred leaves). They are all quad based though, so I started trying to create a very basic script to loop through visible faces > select all linked > unwrap it using Follow Active Quads.
If it helps this is the average leaf appearance

It works for the most part for single selections, however I always get RuntimeError: Error: No active face is not selected, when I try to loop over all faces.
According to this answer adding it to selection history should do the trick and set a vertex (face also?) as active, but it is not working for me.
This is what I cobbled up copy pasting from here and there.
import bpy
import bmesh

# Get the active object
obj = bpy.context.object
# Get the active mesh
me = bpy.context.object.data

#get bmesh (Object needs to be in Edit mode)
bm = bmesh.from_edit_mesh(me)
faces = bm.faces[:]

for face in faces:
    #Select a face
    bm.select_history.add(face)
    #Select linked geometry
    bpy.ops.mesh.select_linked(delimit={'SEAM'})
    #Unwrap using Follow Active Quads
    bpy.ops.uv.follow_active_quads()
    #Hide when done
    bpy.ops.mesh.hide(unselected=False)

My coding skills are admittedly weak at best, so if anyone has a better suggestion with or without scripting, please shoot

I don't know why, but first thing I have think of reading this question was this: https://blender.stackexchange.com/questions/72011/how-can-i-use-a-procedural-bump-map-to-replicate-a-natural-pattern/79338#79338

That is indeed remarkably similar to what I am trying to achieve in terms of UV result, yes. It is probably a bit simpler though, because all tree leaves are basically a quad strip. consisting about 1 to 4 quads. I was trying to find a simple way of marking start and end points on all leaves, but can't seem to manage it easily.

You can change the active bmesh face with bm.faces.active = face, you can select a specific face with face.select = True but I doubt that is going to help a great deal. You can manuallly select all and unwrap following active quad, then use Pack Islands in the uv editor to spread them out.

You can set the active face in your loop with bm.faces.active = face.
With what you have so far, you are looping through every face and doing select linked, even if you may have already unwrapped and hidden the face.
The following script seems to do what you are trying to accomplish.
import bpy
import bmesh

obj = bpy.context.object
bpy.ops.object.mode_set(mode='EDIT')
bpy.ops.mesh.select_mode(type='FACE')
bpy.ops.mesh.select_all(action='DESELECT')
bm = bmesh.from_edit_mesh(obj.data)

for face in bm.faces:
    if not face.hide:
        face.select = True
        bm.faces.active = face
        bpy.ops.mesh.select_linked(delimit={'SEAM'})
        bpy.ops.uv.follow_active_quads(mode='EVEN')
        bpy.ops.mesh.hide(unselected=False)

bpy.ops.mesh.reveal()
bpy.ops.mesh.select_all(action='SELECT')
bpy.ops.uv.unwrap()
bpy.ops.object.mode_set(mode='OBJECT')
bm.free()

Ah yes excellent that is exactly what I was aiming for. That was another point I meant to fix, but my skills got in my way. As it stands mine is pretty dumb, brute-force looping over every face more than once, but I had not figured out how to filter out hidden faces. Many many thanks, will give it a try later today as soon as I'm back at the computer but looks very promising.

Alright, just tested it, takes quite a while to run on my complete mesh (which is totally expected) but works like a charm. Just made a few tweaks for my taste, like removing bpy.ops.uv.unwrap() at the end since I want all islands to totally fit the bounds so they completely cover the potential leaf texture. Again many thanks


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Correct vector input to map texture light in Cycles
What is the correct vector input for a texture connected to a Cycles lamp so that I can make a projector-like textured light?
I am trying to make an projector-like effect with a textured light in Cycles, currently trying it out with a Spot type of lamp, but I am open to any solution involving other lamp types if they work correctly.
The problem is that whatever vector input I use, the texture is always projected downwards, towards the global $-Z$ axis in scene world space, no matter where I point my spot light. I would like to have the texture always project "forward" towards the the direction the spot light is pointing, in the local $-Z$ axis.

The plan would then be to use this spot at several places in my scene, pointing at different directions, and as it currently stands I would have to have a different node setup for each spot instance, manually compensating for each unique rotation in the scene, which would quickly become unpractical.
I have searched around the internet and I am currently using a solution similar to the one on this BSE question.
Is there any better method, perhaps involving some funky Vector Math, or is this not currently supported?

What about having the light still in the scene and rotate everything around with camera? Motion is relative. You can workaround around this like that. The texture coordinates of lights does not follow the light's local transforms..that makes it very hard to do what you want - the solution won't be trivial if there is any at all.

Also what about the UV project modifier to project a texture with round alpha with emission shader onto some geometry using the UV's

Still light and rotate the scene would be quite cumbersome to manage on a large scene, and would only ever work for one spot per scene unfortunately. The UV project modifier does make the desired effect but as I understand would only work in one object at a time, so it would also be a really cumbersome solution to light up a complex scene with lots of objects/lights. Thanks for the input though

One way to accomplish this is by using drivers to rotate the coordinates according to the rotation of the lamp.

Add a mapping node between the texture coordinate node and the texture
Add drivers to the rotation values with  RMB> Add Drivers
Open the graph editor and switch from F-Curves to Drivers in the header
With the lamp object and mapping node selected, set up each driver by selecting the appropriate driver type and transform type:

Result:

This seems to be working reasonably well, best solution so far. I had never used drivers in Blender before. Is there a way to specify the driver to take the value automatically from the object its applied to (self?), so that on duplication new spot (spot 2, spot3) objects are automatically driven by their own rotation instead of the original spot's (spot 1) rotation? That would definitely ease the process.

@DuarteFarrajotaRamos Unfortunately no.. I sure wish there was such a thing, but some workarounds are possible

Ah I see, one can only dream... Thanks for those links, I'll look into those solutions tomorrow, and also thanks got the answer.

I may have found a similar solution using area lights instead, in case you are interested. Answer posted bellow

Someone 'up there' must have heard our prayers. \o/ Unless I misunderstood this commit, from henceforth self reference now seems to be supported in drivers for upcoming Blender builds.

Indeed, though im not sure it helps in this case. From a quick test it appears to be a reference to the datablock containing the driver, in this case the mapping node itself..

Hum, that's right, I'll have to give it  a test when I get an opportunity, but one would need a reference to object 'self' not object data in this case. Oh well I guess we are a bit closer at least.

Sounds like this commit may bring welcome changes to mitigate this problem https://developer.blender.org/rB1272ee455e7aeed3f6acb0b8a8366af5ad6aec99

You can do this without drivers.
You can achieve it using an area light instead of a spot light, then make use of the Geometry node's Normal and Incoming socket and subtract them using a Vector Math node.
It still suffers from tiling/mirroring artifacts at extreme angles like the solutions by @gandalf3, but those can be adjusted with the Vector Mapping node as long as multiple instances of the light are maintain within a certain angle threshold from eachother, and overall it seems like a more maintainable solution in the long term.

Blender 2.79+
As of Blender 2.79 Blender, Cycles can correctly use lamp texture coordinates directly for Spot, Area, and Point lamp types without any further contrivances.

Committed by Lukas Stockner Cycles: Implement texture coordinates for Point, Spot and Area Lamps
Cycles: Implement texture coordinates for Point, Spot and Area Lamps
When using the Normal output of the Texture Coordinate node on Point
and Spot lamps, the coordinates now depend on the rotation of the
lamp. On Area lamps, the Parametric output of the Geometry node now
returns UV coordinates on the area lamp.
Credit for the Area lamp part goes to Stefan Werner (from D1995).

Just use the Normal output on the Texture Coordinates node as vector input for a texture.

If you are using an image based texture you may need to offset the texture coordinates by $0.5$ units on $X$ and $Y$ axis using a Vector Mapping node to center the image on the projection direction.
Smaller sized area lights will produce sharper image projections.

As Duarte mentioned, 2.79 fixes light projection so textured lamps can be rotated, but to make a spotlight into a "normal" projector the image needs to be centered and warp adjusted. Added node setup for reference.


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AMD RX 460 GPU multiple layers incorrect render
I've come across this weird issue.
I have two layers I want to render and combine. Those were set up with the "Setup Tracking Scene" button. The first layer always renders without problems. However, the layer that contains my shadow catcher renders with the top of each render tile's top missing, or artiffacted (based on what tile size I choose). But when I turn off rendering for the first layer, the second one renders fine. Also, if I render on my CPU, everything renders OK, but it takes about twice as much time (I'm using an old Athlon II).
Here's what the scene looks like:

And here's the background layer rendered:

I'm using cycles in Blender 2.78, on Arch linux. My GPU is an AMD RX 460.


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Weird shadows when using solidify modifier on hollow cylinders
I'm seeing weird shadows when using the solidify modifier on hollow cylinders. I've verified all normals are correct. I can't seem to find any way to fix this. The shadow problems carry over to Unity when imported. What can I do to fix this?

Add an Edge Split modifier to your objects or turn on Auto Smooth in the Object Data tab

@DuarteFarrajotaRamos Will the Auto Smooth export to Unity?

@cmomoney Yes AFAIK.

Not sure, never used Unity but if it doesn't, Edge Split most likely will.

Looks like it could be a smoothing problem. Try using a Edge Split modifier after the Solidify modifier.


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Cannot Move Object That is Keyframed
I have a sphere in my scene, and I keyframe its position. However, I later decide to change its position on that keyframe, so I go back to the keyframe in question, and attempt to move the object. I cannot. It seems that Blender will not let me move an object on an existing keyframe. Is there a setting I am missing? Also I cannot adjust it's position between two keyframes to add a new one in the middle. It seems as though setting a keyframe locks it in stone. Any help would be appreciated.

Select the existing keyframe you wanna remove and press 'x' -> delete keyframe

maybe share your file (or just an object/armature that doesn't work anymore): https://blend-exchange.giantcowfilms.com/

You can right click the key frames and clean them or you have to delete them and place the object in desired position and then add the key frames.

Ok well, I had a dynamic paint modifier on the object. I removed that modifier, and like magic, i could move the object and key it again on the same frame. Looks like it may have just been a bug. I was using a beta version. I switched to the latest stable and I no longer have the problem. :) thanks for your tips


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How to animate a kite tail?
I would like to animate a kite kind of character for a little animation.
Unfortunately i'm running into a couple of issues when it comes to (easily) animating the tail.
Now, i want the tail to "Straighten out" progressively in the direction of the bone that's connected to the kite itself.
While also still trailing the movements of the main body, regardless of scene wind or gravity direction.
I've gotten nowhere so far so i stripped my scene down to a skeleton so there is as little mess as possible.
I would prefer bones, as i can mess with those in the target project easily.

List item

Cloth Simulation
Simple Cloth simulation seems to work quite well with Wind effector.
.
Just play anim and move (G) the Empty arround.
It can be used as a proxy mesh for more detailed model with Surface Deform Modifier.

Spring Bone add-on
just a quick test ... it has gravity parametr, but they can't be influence by effectors like wind.
Download add-on from Github

Add-on in included in blend file too.

... and if @egg_etc really does want bones, they can always be bound to your cloth sim like this.. but it's a rather long video.

@RobinBetts I was sure I saw it somewhere :) thanks. Also there was an addon jiggle bones that would probably worked as well, but I think he wants to avoid physics, right?

We'll see. Your answer seems just right, to me.

I think jiggle bones is the thing im looking for actually!
Didnt know they involved physics though...

Nice find! That's a really useful one


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Controlled cloth rip/tear
Hello blender stack exchange.
I'm looking for a way to have a controlled tear.
Like as if i'm (tool) ripping vertices one by one or as a group in between frames.
But preferably something i can trigger or include in a key frame.
Think the seam of your butt splitting for bending over too far.
Or the star shape when a lion jumps through the covered hoop in the circus.
I've not mastered vertex groups enough to get it to work.
Neither have i head any success with seams.
Anyway, sorry for the lack of Jargon, i don't know what im looking for or what it's called.
Thanks for expanding my knowledge with yours!

Not a strong point for blender. You can find a few tutorials like this one and there is a paid addon that is meant to make it easier.


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Particle system to add boils
Hello blender stack exchange.
I'm trying to make a character look progressively more sick by having boils pop up on the skin.
They dont shrink, or grow, they just pop up.
However, i see that in the particle system i can not keyframe the number of emissions.
This leaves me stumped on how to control the amount of boils over time.
Any tips or methods that allow for the random placement of objects on a mesh to pop up?
Or am i in the right direction but the wrong settings.
It's basically the sprinkles part from the blender guru donut tutorial.
Thanks in advance!


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Wave modifier Propagate Vertically
I might just be trying the wrong tools for the job.
But im trying to get a wave modifier to propagate it's waves vertically without having to model at a 90 degree angle.(i like the assigned rotation as is)
I can get the desired motion by parenting it to an empty and moving that around.
However not along the desired axis.
Any ideas?

Undesired motion.

Desired motion after applying a 90 degree X rotation and rotating back. (having -90 degrees transformed.)

I just figured this out myself.  In object mode you have to press ctrl + a and apply your rotation so the global rotation turns to zero.  Or just rotate your mesh in edit mode, and it will keep the same global co-ordinates.


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Gravity and Teleportation in fly mode
When I press shift + f and enter fly mode, while flying around my scene, I noticed pressing tab doesn't toggle gravity, and when I press space I don't teleport either. Is there a user preference or something that I am missing?

All user preferences should be located in the User Preferences window (Ctrl+Alt+U to open).

Those shortcuts apply to Walk Mode not fly mode. Make sure you are in the correct mode.
see https://docs.blender.org/manual/es/dev/editors/3dview/navigate/walk_fly.html

The shortcut for them is the same, mode which will be turned on should be choosed from User Prefs.


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Converting .3mf to .blend
My friend sent me a .3mf file to modify for him to 3d print. Is there a way i can convert it to a file type, that I can use in blender?

Microsoft 3D Builder (included in Windows 10) can export to obj, stl, ply

Is this preserving or converting olor data?

At the time of this writing (April 2017), it appears that this might need to make use of an external platform like Spin 3d from NCH Software; there does not presently seem to be a way to do it directly. However, that said, the 3MF format specification is open source, and I would expect that there will be, sooner or later, the possibility of direct import to, and direct export from, Blender.
Implementing either of these will take programming capabilities that are outside of my skillset, so I won't have direct involvement.

Do you know any online conversion tools?

@OneStig http://swiftconverter.com/convert_3d Also, lemon suggested using Microsoft's 3D Builder if you have Windows (or a VM of it)

Is this preserving/converting color data by any chance?


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What does the "Simulation Threads" setting in the fluid simulation do?

I was just wondering what that setting below the bake button does. Anyone know? Thanks in advance.

It controls how many system processing threads are used to calculate the simulation, if you have a multithreaded CPU

allows you to set a specific number of threads...otherwise, zero means "automatic" (it should use allo threads available on your system)

How do you even get that button there? I'm on 2.79 and I don't have any Simulation Threads control.

It adjusts how many threads are used to calculate the simulation, 0 means "automatic"
If you hover over the label:

Override number of threads for the simulation, 0 is automatic


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Find flipped/mirrored UVs
I made box mapping to model. 50% of UVs became mirrored. I need to find mirrored parts of UV and scale them to -1. How i can find them?
And second question as part of my problem.
How i can fast show texture grid in viewport. I already have a lot materials with maps. I can't every time switch diffuse map to my custom UV grid texture for checking mapping.


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Deleting faces messed up
I am modeling a Bus for a cartoon project. I am looking for a model some thing like that:

In my model, I want to get rid of the area showing in White color.

Making it glass will not help me as it will take too much additional light effects and extra rendering efforts.
When I tried to delete the White faces it end up with very bad result:

Please suggest some solution, Thanks in advance.

First of all in your modifier stack Mirror should be before Subsurface, and secondly, because of Subsurface, Edges are rounding up. You will need to use combination of Creases/Proximity Loops to harden them. If you want detailed answer you will need to upload your blend file.

Simplest solution might be to just make it transparent. Don't believe it will add render time as no bounces are calculated.

Thanks, Swapping the subsurface with mirror helped a lot :)

Can you please post this solution as answer, so that I can accept it correct?


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Rigify posing library
Rigify is seems to be a popular plugin for rigging. If a person is using human rigging based on the Rigify, are there any pre-defined poses or library for posing?

As Rigify is a very flexible tool, a pose that works for a Rigify Character will not work with a different Rigify Character. To transfer poses (and animation) from a rig to a similar one you should do a "retargeting", which is an option that some softwares have (like UE4), but not Blender, unless there is some addon that I don't know.

Isn't that what the Motion Capture Tools addon is for?

if rigify were a very flexible tool as you say,a pose that works for a rigify character will work with a different rigify character ! yeah,you can use the retargeting but it takes a lot of time.


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Subtitle like text always facing to the camera
I am using the blender cycles render as png or jpg in first step and than I add these images to create a movie. It will help render in parts for me.
I want to add the text in the video that always facing to the camera, like a subtitle.
I tried to add the text and align it to the camera but result is not very good like this
Is there a way to add such text? Thanks in advance!

Just add a Text Effect strip in the VSE

Thank you that will be really helpful, is it possible to adjust the fonts?

You can use a "copy rotation" constraint on any object, target to the camera

There is a typo in your video. The color is "grey", not "gray".

@yann https://en.wikipedia.org/wiki/Grey

Oh, i didn't know that. Well, that's embarassing.

@BlenderForYou unfortunately as of 2.79 it's not possible to alter the font, only some of its properties.

@BlenderForYou now it's possible to change the font in the new 2.8 beta

Setup a new Scene for text.
Select the Camera and change it to Orthographic.
Properties > Data(Camera icon) > Lens > Orthographic

Reset Camera Location (Alt+G) and Rotation
(Alt+R).
Move Camera along Z-axis till it is above 0.
Text Object can be place on the X-Y plan as you like.

To combine the animation and text, crate another new Scene and import the 2 Scenes into VSE.

I know this is an old question but another way of achieving can be just making the text a child of the camera, so wherever the camera rotates the text will always face the camera.
Though, a 2nd step would be needed to make the text render on top of all other objects for cases where they come between the camera and the text.


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How to get a lighthouse to shine a lightbeam
I was wondering how i can get my lighthouse to shine a clean and realistic beam.
I cant get my volume density low enough to get the desired result.
Do any of you know how to maybe get a volume emission to work like a gradient?
So that the light cone is less intense the further its away?
or can i add some invisible geometry that is in the way of the light but in all other respects transparent?
Light baking maybe?
Summin like this.
https://captainkimo.com/foggy-morning-jupiter-lighthouse-with-light-ray/
or dis.
https://twistedsifter.com/2013/07/pigeon-point-lighthouse/

It looks like this node setup works not too bad:

I've created a simple light ball for the light source, maybe you should add a bit of glow around as it's explained here: How do I make a luminescent gas cloud?
Now, for the beam, first, create a conic cylinder.
For the length gradient, mix an Emission node with a Transparent node, use a Gradient as factor, and a ColorRamp to control its intensity.
For the width gradient, mix the first Mix Shader with the Transparent node, use a Layer Weight as factor, and a ColorRamp to control its intensity.
To add a bit of noise you could mix the previous nodes with the Transparent node, with a Noise texture as a factor.


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Mirroring this object gives unwanted results

Ive been trying to follow this tutorial but i got lost...
https://www.youtube.com/watch?v=JjW6r10Mlqs
The mirror is inverted... I want it to be a closed object, not open from both sides.

The mirror is inverted... I want it to be a closed object, not open from both sides.

Make the origin of your object to be any of the edges of an open wall

Press SHIFT+S - Snap
To move the 3d cursor to the selected edge.
CTRL+SHIFT+ALT+C - Origin
To move the origin of the object to the location of the 3D cursor.

How do i make those button images for future references? :P I'm a newbie here.

huh? cant seem to find a "how to do it" just "how you SHOULD do it". Kinda confusing


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How to stop bevel modifier weight without duplicated vertices?
I'm using the bevel modifier with the weight limit method in order to have more control about which edge will have bevels, but it has an influence on the connected edges that sometimes I want a hard curve.

The technique I learned is to duplicate those vertices I want to break the bevel because it would generate a zero length edge between them, and that edge will have bevel weight zero.
The problem is if I merge vertices by distance I'd lose that configuration, it requires me to pay attention to always unselect those vertices when I'm doing the merge.
I know I could slightly shift the duplicated vertices in order to not be in the exact same position, but I don't want to corrupt my mesh with imprecisions.
I wonder if the bevel modifier doesn't have some settings at vertex level that would control which direction it's allowed to expand. Or if there is a different technique that would allow me to have fine grained control over bevels.

There is no other way. The particular result you are looking for with bevel modifier requires that particular kind of topology.
You could give the vertices some attribute and make yourself a geometry nodes tool to quickly deselect them.
Use Add Attribute and Set Attribute:

Set Attribute requires the attribute you want to set to be selected:

Geometry node tool:

Then you can access it from the menu:

You can also make a hot-key or add it to Quick Favorites menu.
You could also just make a tool that merges by distance ignoring vertices with that attribute:

Now that you mentioned it, I could also use vertex groups. But I hope blender developers could think about a better solution for that.


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Unexpected "color" transition in half transparent cylinder with Cycles
I try to represent red and blue spheres moving in a tube, and render it with Cycles. I made a part of the tube opaque and another part semi-transparent following the "color based on height" trick. I get the following result, but I am anoyed by the color transition that takes place at the third sphere (from the bottom right). It does not seem to depend on the orientation of the sun.

I built a minimal working example, with a half-transparent cylinder and got the same effect. The corresponding Blender file can be found here. The effect is not present if the cylinder is opaque.

Do you have any idea where this effect come from and how can I avoid it?

It seems that the reason of this shading 'glitch' is topology of your Cylinder. I don't know exactly why this is happening, maybe because of stretched faces (or for sure). When you scale it down on the X axis (to make it shorter) problem disappears.

You have two options:

Add Subdivision Surface modifier.

Add Loop Cut in the middle of the Cylinder (or couple of them to be sure that it doesn't happen again.

Personally I would go with second one as this is 'lighter' solution.


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how to create low poly cliff
I want to create cliff with path to make roads as low poly like in below image.

It's simple, really.
First, you create two cubes, one slightly smaller than the other.

The select the bigger one of them and in edit mode add loop cuts vertically.
Between 24-48 loops should be enough.

Then select one of the edge loops press 'O' to activate proportional editing and then select random falloff.

Switch to top view, click on the respective axis manipulator and drag forward.

Then add 2 horizontal edge loops and repeat the same process with each of the loops. (Adjust it forward and backward as you see fit)

NOTE : Switch between random falloff and smooth falloff if you feel the edges are too jagged.
Then exit edit mode and move the "rough-edged" cube such that it overlaps the smaller cube.

Next, select the smaller cube and and add the Boolean Modifier and set the operation to "Difference", also make sure the Solver is set to "Bmesh" else the poly-flow may not be even and then press "Apply".

You may delete the bigger cube if you have no further use of it. Now, in edit mode, select all the faces you want to make a ledge or road and press "E" to extrude. Extrude till where you want it.

Hope this is the answer you were looking for. :)


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texture stretched
made 1 model after duplicate remove doubles then delete the edges in center. it would make the texture stretch, i delete edges to reduce poly count but texture stretched , how to do it without texture stretch out.

For your model you want to make sure that you have properly applied the UV's for your model. Add seams to areas where it's needed and then unwrap the model each time you make changes to see the final result. verify that the UV's aren't stretching where they shouldn't. You can use the stretch tool to assist with this.

The darker the blue the cleaner the final result will be.


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unwrap cube with circle

make cube, draw circle and extrude in. while unwrap the cube, it did't unwrap perfectly. its unwrap like what in the picture.

What is your question, this is how your object unwraps. What result do you want?

The problem you're having are three N-Gons. N-Gons are faces with more than 4 verts. So you need to change the N-Gons to tris or quads. To triangulate a face, just press SPACE and type triangulate, you will then see the option "triangulate faces".
The first picture shows my unwrap with N-Gons, the second one is with triangles.

However, the right way of doing it (if you want to maybe use sub-d or something) would be like this. You the only would have to deal with the edges going over the cube.:

Go up with this, especially for last example. Some loop cuts trough the mesh would be a good idea to keep quads more square-like. But overall, OP go with this method. It's important to keep topology clean and quad.

Yes, also thought about this. However, i didn't want to do a post about topo in generell, because that#s a whole topic on it's own^^

It's really important to encourage users to use proper topology, sadly many of answers don't take this as an value creating more issues later on.

These are the users, which will never reach a higher level.

You can select all faces without N-gons and U unwrap them, then select the face with the hole in front ortographic view and press U "project from view, then adjust the size of the UV islands.


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Will Blender support design and dimensioning machine drawings?
I am starting a search for software that can support mechanical design.  The CAD programs I have looked at tend to have arcane command language interfaces that make the job of design as much a programming exercise as a creativity tool.
My question is: "Will Blender support design and dimensioning machine drawings?"
If so, where do I go to learn more?

No, hard to say without knowing more about what you are trying to achieve, but unfortunately I don't think Blender is adequate for that sort of work. In fact Blender is particularly unsuited for any CAD-like precision modelling work, and is one of its weakest points. Maybe look into LibreCAD or perhaps FreeCAD is more suited for manufacturing?

While blender is more adapted to creative modeling than technical or precision modeling you can create mechanical models and use them to create good looking blueprints.
In this youtube tutorial, the measrueit addon (included with 2.78 or can be manually installed on older versions) is used to create the measurement lines. The lines and annotations don't show in a normal render, but the addon provides a way to create a render with measurements.

Freestyle can also be used to create outlines for blueprints. This blendertuts tutorial explains how to define solid and dashed linestyles to get a hidden edge blueprint result. It is also possible to get more of a hand sketched result.

The CGCookie archives also has an old tutorial that manually creates text objects and lines to get the following blueprint.


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Warp mesh to retain shape when changing focal length of camera
Bascially, what I want to do is modify the mesh by warping it so that when the focal length of the camera changes, the mesh appears the same to the camera. I'm not sure if this feature is in blender, but if not, how would I go about doing it?

Do you need to modify the mesh, or can you just use two scenes - one for the mesh object and a non-changing camera and one for the scene that changes focal length minus the mesh object?

This sounds a lot like the Vertigo Effect, or Dolly Zoom however those are achieved through camera effects alone, not mesh warping

@CraigDJones I want the mesh object to change; it should distort and warp when the focal length of the camera changes so it appears exactly the same to the camera at a different focal length after changed.

I don't understand. When you change focal length (or FOV) the mesh does not distort, only visually scales. But moving the camera closer/further the subject changes the perspective (visually distorts the object). Can you elaborate what you want more precisely and your end goal is?


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Bad results with cloth simulation - sewing
I am trying to create various clothes in blender by using cloth simulation with sewing, but I am getting quite poor results. In the image below I tried to create a balaclava but it always comes out really wrinkled, with gaps and clips through the base mesh in places.
I tried adjusting various options such as increasing and decreasing subdivision of the balaclava mesh, or increasing the simulation quality steps, but the result never looks good for some reason.
What am I doing wrong?

the gaps are normal (not their size but their existence). You can minimize their size with tweaking the settings and mesh topology. But if you want to get rid of them completely, you need to merge the mesh parts manually or with a script. 2) The more vertices a mesh has, the more wrinkles you can get. But it also increases the chance for unwanted behavior. If it ripples and "crawls", then it is usually a problem with the collision detection. It's a good idea to start with a low-poly mesh.

It looks like you had a low-poly mesh and then applied a Subdivision Surface modifier. This is not ideal because the modifier does not add any needed "threads" (=the edges between the mesh parts) and instead subdivides the existing "threads". The missing "threads" create these large holes. 4) It also looks like your mesh is too small to fit the head. When sewing, the flat mesh needs to be much larger as it is wrapped around a 3D object. If it's too small, you will end up with large gaps because there is not enough mesh. The mesh can be stretched, but that's limited.

Here is a quick example, where I indeed forgot a few threads. This results in a gap/hole at the nose: [1]: https://i.sstatic.net/ZfNh1.jpg - [2]: https://i.sstatic.net/wRqwX.jpg


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Hair particles look different in object mode than in particle edit more
I added a plane to the scene, then added a new particle system for hair and this is how the particles look:

They should be straight lines but aren't for some reason, but when I go into particle edit mode they look like this:

Which is the correct way I want them to look. So why do they look messed up in the object mode?
I tried opening a new empty blender scene, adding a plane with hair particle system and it looked correctly there, particles looked like the second picture in both object mode and particle edit mode. Which means this problem exists only in my current scene. What could be causing this?
Thank you

If you just added the Particle System and did not change anything of the defaults, it is strange that they look like that. In case you did change anything - would it be asked too much if you show some screenshots of the settings? Some things like settings for Children hair particles can change the look in Object Mode (like Clumping  or Kink for example) but that has no effect on the parent particles which are the only ones you can edit in Particle Edit mode so there they are still straight. Maybe upload the file here and follow the instructions there: https://blend-exchange.com

@GordonBrinkmann I didn't touch any settings, simply clicked + to add particle system and thats it. Are there maybe some global particle settings in blender that affect all particle systems? Sadly I I can't upload this particular file.

Any other file where you have similar problems which you can upload? Is there a force field in your scene like wind or anything? Otherwise I'm afraid there is not much we can do, your screenshots don't show anything relevant, no settings, not what else is in the scene that could have an influence... so without any information or the file to check what is going on there it would all be just wild guessing. Did you delete the particle system and added a new one and did it have the same problem?

@GordonBrinkmann Thats it! I have a wind force field in the scene for the smoke simulation, and I completely forgot that force fields also affect  hair particles. If you post it as an answer I will accept it.

You can actually post an answer to your own question and even accept it after a grace period. That would be best because in the answer you could show screenshots of that force field in your scene and how it affects the hair.


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how to make camera look through objects from only one side?
I have modeled a rather small room, and when trying to get the right camera angles I can't fit the camera inside the room without getting too close, so I wan't the walls and ceiling only to be visible if the camera is placed inside the room. Understand?
Make it so the camera can look through the ceiling and walls from the outside, but they still appear in the cameras view when the camera is on the inside looking out?

See the technique described here for a viewport-only effect https://blender.stackexchange.com/questions/70576/transparency-masking-see-through-an-outer-sphere-and-see-inner-sphere-in-true/70619#70619 For Blender internal use https://blender.stackexchange.com/questions/59070/striped-sphere-hide-backfaces/59073#59073

The solution I found that actually worked was, scroll down in material properties, and check Backface culling.

Final result:
This is kinda same idea as @Duarte Farrajota Ramos but it is working in Cycles (viewport/camera).

Mesh:
Your mesh normals should point to the inside of the room as in the image below.

Materials:
You will need to assign different materials for floor and walls and ceiling.

Floor material. Could be anything you want.
Wall and ceiling material. Should look like this and in the place of red Diffuse you can and anything you want. Remember to check if Transparent shader color is pure white. Hex value #FFFFFF.

this solution worked, however the see through walls and ceiling now emits light? why is that and how can one fix such an issue? i've turned off all other light sources, and the room still looks like this: https://imgur.com/a/OSnm3

@jorba it is looking pretty strange and it's hard to tell just from the image. Could you upload you file to: http://blend-exchange.giantcowfilms.com/ or just problematic part of it?

I posted a new thread about this, as it was happening all over my project. here's the link for the new one https://blender.stackexchange.com/questions/98463/why-does-objects-appear-to-be-emitting-light

Hmm, this is I guess the same as another answer.  Anyway, here goes:
Use the "Backfacing" output of the "Geometry" node as the mix factor between your shader (whatever it is) and a transparent shader.

No matter what direction you are looking from, anything with front-facing normals will be transparent.  (As you can see from the picture, suzanne and a point lamp are inside a solid sphere, but in the rendered view you can see everything inside the sphere plus the back wall of the sphere.)
Note, however, that in an enclosed space all of your illumination is going to have to come from inside, and/or windows/openings!


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why do objects appear to be emitting light?
It looks like the bed to the right, the pane beneath the window and beneath the couch are emitting light? why? all light sources except a moon outside is turned off.
All of these materials are basic Diffuse BSDFs. the wall with the window in it has a JPEG-texture wrapped on it.
i'm working in Cycles Render btw

Edit: heres the whole shebang with the layout of it all. the sun and the moon are the dots on the very right. the room where the "human" is sleeping on the couch is to the left. everything outside the room is just scenery, so that's why it looks very sloppy.

the "human guy" in pic 1 has nodes like this:

I have btw tried turning of all the light sources in the Outliner window, does that render light anyway somehow?
uploaded the .blend if anyone is interested

please post a screenshot of the nodes for the guy object.

An emission shader creates a light source, therefore the object will emit light in your scene. Use a different shader(s) if that is not the desired shading for the object.

@Timaroberts but the light is there even if i turn off the emission for the guy, so it's not coming from the object screenshoted above

sorry, didn't know that was possible. revised that and put it where the old one was in the question @cegaton

Mystery solved.  You have a lamp object called "sol kon" whose viewport visibility was turned off, but the render was left on.  That's what the light is coming from when you render.


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How to use opacity map in Blender?
I have textured my object in Quixel and have an opacity map due to a portion of this object being glass. The issue is that when I try to use the opacity map my entire object has transparency and not just the glass. Could someone please show me a node set up (using principled shader) with an opacity map included?

Related https://blender.stackexchange.com/questions/55232/how-to-properly-hook-up-various-maps-types-together-in-cycles

This is not a duplicate. The article suggested has the opacity plugged into the base color, so where do I plug in my diffuse map?


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How to connect Blender to Arduino?
I want to connect an Arduino (eg: Uno) to Blender and animate blender objects based on arduino inputs.

The way I did it was by writing serial information to the usb port from the arduino and reading it from inside blender with pyserial.
I did run this in the Blender's game engine, which may or may not be what you want. The Blender side looks something like this (code is not very clean, I just hacked this together quickly for fun, but hopefully to gives you some idea of how you could implement it):
from bge import logic
import serial
from mathutils import *
from math import *

def startup():
    ser = serial.Serial('/dev/ttyUSB0')

    scene = logic.getCurrentScene()
    object = scene.objects['Suzanne']
    print('startup')

    logic.globalDict['serial_bus'] = ser
    logic.globalDict['main_object'] = object
    logic.globalDict['light'] = scene.lights['Lamp']

def loop():
    ser = logic.globalDict['serial_bus']
    object = logic.globalDict['main_object']
    light = logic.globalDict['light']

    # this is where the data is actually read from the serial interface
    data = ser.readline().decode()
    pot, var, phot = data.partition(";")
    print("pot:", pot, "phot:", phot)

    object.localOrientation = Euler((-.31,0,radians(float(pot)))).to_matrix()
    light.energy = 10 - float(phot) * (10.0/800.0)

The Arduino side is just Serial.printing numbers separated by semicolons.
How exactly you want to animate objects in blender depends on your usecase. If it's for a real time demo, you probably want to use the BGE (or use another game engine entirely, such as godot). If you want to use it as a secondary input device in Blender's viewport (e.g. a sort of DIY 3D mouse), you'll probably want to look at writing an addon.

@Saku I've moved our conversation to chat to avoid cluttering up this page too much. Let me know if you have any issues getting access, I think you should be good.


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Everything is gray
I have a bunch of scenes and there all correct but there's 1 that is broken. When I render its just all grey. There's nothing but grey.
My preview samples: 10
My render samples: 35
My GPU isn't that great, its a 920M GeForce Nvidia
Here's an image of the grey screen when I render it (In the viewport its all fine, everything shows up):
[

It's certainly taking a while to render that gray! It looks black to me, actually. Do you have any lights? And does it have the same problem in Rendered view mode?

did you check for hidden geometry in the viewport that is rendering?


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Blender alpha/transparent texture only works when selected
I have a transparent bubble texture that I got from google and I placed it on a part. I set the alpha to 0, made sure my shading setting is on GLNL like a youtube video instructed me to, but I only get my desired result when its being selected. If anyone knows how to fix this please help as soon as possible.

The first picture is my desired result which is when its selected, the second picture is the result I get, and third picture is the texture I used.

Related: https://blender.stackexchange.com/a/1056/26640

select your object then Go to the object panel in the properties and check Transparency in Display tab for all object you want to see transparent. make sure that you have the correct object selected.

Thank you so much! it worked perfectly, Have a nice day!

@Mariah welcome and don't forgot to select my answer :D


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Mesh Body not showing up in render
Hy guys though i am not new to blender but i am posting question for first time ever.
My problem is kinda confusing, I imported a rigged model from MakeHuman using mh2 plugin and then sculpted model to my need.
Alas, when I rendered it, the body is not showing up in render. I checked restrict render, nothings there. I did change material nothings happening, tried CPU and GPU both and back and forth in Internal and Cycles, but nothing changes.
Anyone who would be willing to look into my problem I would be grateful.
Is it bug?
Please do help me because I need image by tonight. Thanks a ton!!

check the renderbility toggle for that object in Outliner.

Hard to tell from image alone. Can you upload your blend file? It's possibly a normal issue


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Snap during transform can not snap to what I want
Why can't I snap the point I chose to the target point.
I tried for a long time to do this, but no use!
Could some help me? Thanks !

unfortunately, blender doesnt work that way...(out of the box) But you can get addons. Or you can snap the origin point to the 3D cursor.

at first i use the origin and 3d cursor function,but it is too slow for this simple action.thank you friend!

But if you join the two meshes into a single mesh, it acts better in edit mode. You can select one face and press (Ctrl+L) to select just on of the objects.

Please clarify what you want to accomplish, the question is extremely unclear.

oh,it can works,thanks,join them into a single mesh is good way to do this.

@NᴏᴠɪᴄᴇIɴDɪsɢᴜɪsᴇ thanks man ,i just want to move a object to nearby another one with there vertex superposition，snap can do this perfectly，but as i post ，try a long time but still have some confuse  with the snap.

@NᴏᴠɪᴄᴇIɴDɪsɢᴜɪsᴇ http://i.imgur.com/O9UoX1u.jpg

Blender does work that way. Snap During transform can snap objects and you can select between modes to achieve desired result.

In case of complex objects Snap During Transform might not guess where should be the vertex you'd like to snap. If using Closest method while in Object mode, it will depend on object's bounds. If using that method in Edit mode, it will use nearest vertex to snap to.
To snap object's vertex (and whole mesh following it) to vertex of another object use Edit mode (without any joining).
Enter Edit mode for object being snapped, select all and activate Snap During Transform:

To implicitly snap desired vertex and make mesh follow it use Active mode;
To snap the closest vertex to object being snapped to and make whole mesh follow snapped vertex use Closest method.

Note that depending on further actions with the object you might want to change its origin.

Solution in object mode :

Add an empty
Set snap to vertex option
Grab your empty to the needed vertex of the mesh to be moved
Shift+RMB to select the mesh to be moved additionally to the empty
Then grab them both to the destination

Oh thanks man!Maybe I am too late,but thanks!

A bit of explanation about the reason it can't work without the empty, and the role the empty plays, would be useful.

@mins, the empty is a "one point" element which helps to aim one vertex in the target mesh.

Since @lemon's answer, in 2.8+, we have been able to drag the cursor around, opening another possible workflow, also without having to go into Edit Mode.
The 'Center' snap-from entry in the snap settings refers to the active Transform Center / Pivot Point, as set in the header dropdown. This can be the 3D Cursor. So, with the Transform Pivot Point set to 3D Cursor, snap-from set to 'Center', and snap-to set to 'Vertex', you can ShiftSpacebar - Spacebar activate the cursor tool.

Drag-snap the cursor to the desired source vertex
G Drag-snap the object, snapping where the cursor was at the beginning of the move, to the desired target vertex.

@glades Glad that helps! Funnily enough, I prefer lemon's way, maybe because I'm a bit of an old-timer in more primitive packages. In CAD-like work, I tend to have a collection of home-made jigs lying around: angles, lengths, orientations, arcs, stashed in simple objects/Empties.


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How to model braided nylon sleeve
I am trying to make a model of a braided nylon sleve which I want to use for kitbashing.
Here is what im trying to make

I know how to make the tube inside and everything, but I'm struggling with the braided nylon. I want to make the whole muscle straight and in a resting position so I can later deform it as desired.
I know that patterns like this are easy to replicate with normal map patterns in some software, but i am trying to make it as a high poly model I can use while concepting and kitbashing.
The biggest issue I am having is making a single segment that can easily be arrayed and modified so remains similar to it.
So far I have tried using a cylinder, cutting all the faces, modifying it and arraying it and twisting but it only turns out looking like a basic net.
If you could just direct me to what I could do, and you dont need to specifically say the button needed, I  know where everything is located and all the buttons, I  just need to figure out in which order/way should I go to make this.
Thanks in advance for any help.

https://blender.stackexchange.com/questions/131443/braided-hose-modeling https://blender.stackexchange.com/questions/58959/how-to-model-braided-nylon-sleeve

Add a mesh circle to your scene
Extrude it vertically
Poke its faces with Alt + P
Remove the vertical edges by selecting one of them and pressing Shift + G > Select Grouped > by Direction
Remove the triangle faces with the same operator by Polygon Sides

Add an empty object to the scene
Add a Bezier Curve object too
Now add an Array modifier to the circle
Clear the pre-defined relative offset options
Check the Object Offset option
Pick the previously added empty object
Set it to Fit Curve mode
Pick the previously added Bezier Curve
Now adjust the Position of the Empty to match the rotation and the height
Move it up half the distance extruded in point 2

Rotate it about the Z axis $360°$ divided by twice the number of edges of the circle (by default a circle has 32 edges so $360° / (32 * 2) = 5.625°$)
Rotate the whole Circle + Empty in the Y axis $90$ degrees
Add a Curve modifier and pick the same curve used in the array
Now add a Wireframe modifier
Adjust the curve's shape as necessary

Control the dilation/contraction of the nylon sleeve with the curve vertex radius

Enter edit mode in the curve, select a vertex and press Alt + S by default.

Profit!

First of all thanks a lot! :D this is exactly what i needed.The biggest issue i had is getting the squares cut with an "X" and getting it to look like a net,but with this it made it much simpler.

There's an alternative route to diagonal meshes, which is quicker than the array method already given, but more destructive: you can't change the number of mesh elements as easily, later in the process.

Starting with a subdivided cylinder
In Edit mode:further subdivide the edges you wish to make diagonal:
CtrlE Edge menu > 'Subdivide'
Unsubdivide the same selection withan odd number of iterations, (here, 1):
CtrlE Edge menu > 'Unsubdivide'
Construct your deformation curve, ( easiest with coincident origin with the mesh to be deformed, aligned along deforming axis)
Add 'Curve' and 'Wireframe' modifiers, as described fully in Duarte Farrajota Ramos' answer.


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Rendering a stereoscopic image in Blender 2.77
In am interested in setting up cameras and rendering settings to create a stereoscopic image or animated scene.
I have found easily how to export one image where the red and blue channels are slightly off (which is good for stereoscopy that involves red/green glasses).
But what I am trying to achieve is stereoscopy that can be looked at without glasses, for a short period of time, by crossing one's eyes. Such as this image, in which the left and the right views are combined in one image (courtesy of Wikipedia):

I have found stereoscopy settings in the right-hand side menu of the viewport, as well as settings in the Scene properties panel, but my various attempts didn't result in two images side-by-side being produced, but always them overlapping.
The closest I have gotten to what I'm trying to obtain are these settings in the Camera panel:

I quickly run into the limits of the two fields and the resulting images are not rendered with their own colors. The angles of the cameras are also hard to figure out.
Ideally, the two left and right views would have all their colors, and be exported as one image side-by-side. This way, only one image would be exported for each frame in case I create an animation with this technique.

I  think this will answer the image format question: http://blender.stackexchange.com/questions/42289/stereoscopic-sbs-is-anaglyphic/50263#50263    Regarding cross-eyed images. I think if you flip the left and right image you will get what you want.

There's also another way to do it here: http://blender.stackexchange.com/questions/6277/different-camera-settings-for-different-render-layers

The easiest way is probably using two different camera objects in your scene instead.

I can't seem to make use of these comments. Anyone got a screen grab of what it looks like on their end? (viewport + rendered version). Ideally both cameras should point to an object's origin, not away from it...

Still waiting for an answer with screenshots to mark this as answered, if possible please make an answer, even if the best solution out there involves making two cameras and aiming them manually towards the same point... thanks!

@DuarteFarrajotaRamos could you write an answer in which two cameras are used (I'm still confused about how to use two cameras in one same project), and maybe they would focus on the same empty? Haven't found how to do this still but your suggestion makes sense and seems like a good option!

I don't think people have been getting your comments. I have asked precisely about this before, and unfortunately Stack Exchange doesn't notify users about comments unless you ping them like you just did to me. Anyway I'll try and think of a solution and post an answer as soon as I can, but my computer is currently busy rendering a project I have limited usability, I probably wont be able to until tomorrow.

@DuarteFarrajotaRamos no worries. Thanks about the heads up regarding comments. Sometimes I forget or on the desktop version of SE it doesn't work well

OK, after some fumbling around I found a workable, if a bit hacky, solution for this.

The main issue here is that Blender's compositor  was designed assuming all frames and image are the same size, and thus wasn't really made for handling differently sized pictures or composing images of arbitrary dimensions.
Anyway it's a bit of a involved process that will rely on a three scene system Scene A, Scene B and scene Size

Create you scene Scene A regularly (set up your render objects, meshes, lights, etc)
Make sure you add all objects to a certain group with Ctrl + G (that we shall call for the sake of example Group) including lights but excluding your camera objects. (Use a purpose made collection for this goal in Blender 2.8+)
Make sure this group's center is at the scene 0,0,0 coordinate
Create your camera object wherever desired but do not add it to this group
Set up your render size and render preferences all as desired
Now add a new scene Scene B to your blend file using the option Copy Settings

In the new scene add a new group instance of the previously created Group
Make sure this group instance center is also at the scene $0,0,0$ coordinate
Make sure the new scene is using the same World shader and all other scene settings match, so that the two renders are alike.
Go back to Scene A select your camera object and link it to Scene B by pressing Ctrl + L > Make Links > Object to Scene > Scene B
Go back to Scene B and select the linked camera and make it's object unique by pressing U > Object. For Blender 2.8+ go to Object > Relations > Make Single User > Object. This will keep the camera settings linked and in sync with the previous one, but allow you to move them independently.
Now Place this camera as many units to the side as desired. If you want them both centered, you may want to consider moving one $X$ units in one direction in Scene A and the other one $-X$ units in the opposite direction in Scene B. If they are somehow rotated in global coordinates you may double press X > X to move them in local $X$ axis. If they are animated consider parenting them both to a helper empty object, and animate the parent object instead.

Your scene should now be setup, now you need to setup the rendering system to automate image assembly.
Add a third empty scene called Size using the New option from the menu. This scene will only exist as a hack to setup an image size. Disable everything in the render layers so it will render instantly. The only important thing to do here is to make sure you setup render size double the width of the previous Scene A and Scene B.

Say if scene A and B have both a rendering size of 800 x 600 (and this must be kept in sync manually) scene Size must have a rendering size of exactly 1600 x 600 so images can be correctly combined side by side.
Add a camera to the scene Size (anywhere is fine, it won't be used much anyway) and set it as active.
Now you must specifically set up compositing in scene Size and configure your compositing nodes as shown bellow, so Blender will automatically fetch the renders from the other scenes and compose them into one large stereoscopic image.
Add two additional Render Layer nodes, and for each change the Scene dropdown menu to pick both Scene A and Scene B and combine them using Alpha Over nodes after transforming them half their with in the X axis.

You must always render from scene Size from now on to obtain your stereoscopic images automatically, and you will probably have to update each scene's render manually from the little rendering buttons in the nodes themselves (instead of just pressing F12) to render from other scenes, otherwise Blender will probably render them in the incorrect size because it was never meant to render this way.