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Object missing parts in the viewport using eevee
I was working on a model inside blender 2.83 and suddenly it turned into like broken object. The problem remains in rendered mode in (eevee)

but disappeared in cycles rendered mode.

Please attach your simplified  blend . It can be a part of model just with issue still visible. Use https://blend-exchange.giantcowfilms.com BTW your screen is from Solid mode.

You may try adjusting the viewport clipping, or press , on the nupad with the object selected


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Why are some faces darker than others in edit mode?
Everything else is fine, it's not ngon or something, it's a quad, so why does this happens?

Hello :). Does this answer your question? Inaccurate shading on object

it would really help if you get the screenshots from another angle

Used this: https://docs.blender.org/manual/en/2.79/modeling/meshes/editing/subdividing/vertex_connect.html On these  and it helped!

source: Stack Exchange

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

sort: votes


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How to fill base for 3d printing a topographic map
I would like to 3d print a topographic map of the world. I’m starting from the following grayscale PNG.

I have previously played with Blender to render this shape using a grid mesh and the displace modifier. However just exporting the resulting mesh to obj/stl hasn’t worked with my slicing software.
I suspect the main problem is that the grid isn’t “filled” underneath -- how would I go about fixing that?

@susu Sure, I've edited to leave only one question

For similar questions already on this site, use the search box at the top. https://blender.stackexchange.com/questions/62384/how-can-i-make-a-closed-flat-base-for-an-object and https://blender.stackexchange.com/questions/32688/stl-files-and-adding-bases and https://blender.stackexchange.com/questions/192625/how-to-create-a-flat-base-to-a-photogrammetry-model-in-blender and https://blender.stackexchange.com/questions/170655/adding-thickness-to-3d-printed-topographic-map and https://blender.stackexchange.com/questions/41045/how-to-solidify-a-complex-2d-render-from-pix4d-for-3d-printing

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


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Can't solve my camera
I was tryng to track my scene. I made and image sequence then exported all the jpg pictures. To get tracing points I used the "Detect Features" option to create keyframes. When I was ready I pushed the button "Solve Camera Motion" And it displayed that:
Atleast 8 trackers...

Can someone help me find out why it says that and could help me fix it?
Video: https://youtu.be/xEaocgkWAVM

You won't be able to solve a shot like that with the default solver. The camera is stationary and is rotating only, in those cases you need to solve as tripod. Be aware that this will only reconstruct the rotation of the camera, but will not yield any 3D information.
Read: How can I get better results when doing camera motion tracking?

Yeah, but I didnt shoot it on a tripod. It was shot handheld

It doesn't matter, there is no parallax information on the shot, It can only be solved as tripod.


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Help to reduce size of .obj file?
I am new to Blender and 3D modeling.  We purchased some 3D models of some beverage packaging containers we use but they seem to have too many polygons.  I downloaded Blender and followed the advice of a few tutorials and videos to reduce them but am really struggling.  I simply need to make one file less than 200,000 polygons for a online application we are trying to use.  Would anyone be willing to help with this?
It is a simple ask, but trying to learn Blender for this one small project feels unecessary.
Any help would be greatly appreciated.

Maybe try using a Decimate Modifier? If your object is round(ish), try "collapse", if your object is flat(ish), try "planar".

Hello, is your object photoscanned ? You can use the decimate modifier, or use the remesh modifier and play with the settings

Hello and welcome. This site goal is to build a high quality database of questions and answers. If your goal is not learning and you just want to have someone do it for you, then it is best to ask elsewhere

Can you post the model somewhere?
If you can import the model successfully, Select it, go to the Modifiers Tab and add the Decimate modifier.  Under the Decimate modifier, there are three "modes" for it to work: Collapse, Un-Subdivide, and Planar.  If you are going to be using the model in a game engine, you might want to skip the Planar setting because it will give you n-gons.  You might also want to check the "Triangulate" box - then play with the "Ratio" slider until you get the polycount and visual quality you want.  \
Poly reduction is more forgiving on organic shapes (you can get away with more "generic" reduction).  If the shapes are very clean/defined, generic reduction might not work very well and you would have to consider hand-reduction or retopologizing.
If/When you are happy with your result, you can go to the drop-down arrow in the Decimate modifier panel and select "Apply" and export your model (or, you can export your model straight-up - but you want to make sure the "Apply Modifiers" option is active under the export options).


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Does anyone know why OS X has problems with Image Editor?
I am trying to use the UV/Image Editor to texture paint and this is all I am able to see. The first image is when I opened the file and the second is when I zoomed in. I have done a render on a different program and while it was rendering the same visual problems arose, but the image rendered and saved fine. Any ideas what causes this?

My system information:
Blender 2.79
Model Name: Mac Pro
  Model Identifier: MacPro1,1
  Processor Name:   Dual-Core Intel Xeon
  Processor Speed:  2.66 GHz
  Number Of Processors: 2
  Total Number Of Cores:    4
  L2 Cache (per processor): 4 MB
  Memory:   18 GB
  Bus Speed:    1.33 GHz
  Boot ROM Version: MP11.005C.B08
  SMC Version (system): 1.7f10
Graphics Card: NVIDIA GeForce 7300 GT 256MB VRAM

I have no issues on a similar system here - can you double check the nvidia driver first and then also check if there is an OS update?

I could not find a nVidia update, and there are no updates for my current OS
System Version: Mac OS X 10.6.8 (10K549)
Kernel Version: Darwin 10.8.0

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


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How does BLAM work?
so I installed Blender a few days ago, and after playing around and getting used to the basic controls and shapes, I decided that it would help to use references pictures of houses and stuff like that, but it was really hard for me to match my camera with the image and my cubes ended anywhere but where they were supposed to be, and that's how I discovered BLAM. I thought it would be really helpful so I installed it, but after an hour I still cannot decipher how does it works. The original tutorial video is really old, and I don't get how to use it, can any of you help me a little bit with this?

Blam has been updated a bit since those tutorials.
Use the MCE (Movie Clip Editor) or Stabilizer, to load the clip. The Blam addon should appear in the Tools panel in a tab called Miscellaneous. Turn on the Grease Pencil in the Properties panel and add 2 layers. Set the color if you want to tell them apart.

To draw a straight line with GP press Ctrl + D key, then click and drag, while dragging release the Ctrl key but KEEP pressing the D key until you finish.
I find that zooming the image up is useful. It allows you to trace the line in the image better.
Remember to have your camera selected and preferable have the image active as a background in the 3D view. Then press the Calibrate Active Camera button in Blam.

The background image is only meant for modelling and placement assistance, you will still have to composite the model onto the shot. You can either use a texture projection (from the camera) onto a plane or model, or use the compositor.
Also I made a tutorial on my YT channel about this a little while ago.https://www.youtube.com/watch?v=km7ko2yddx8

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


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How you denoise renderered images in Blender?
I am wanting to use Blender as a denoiser as well as a renderer, but I can't find how to bring an image in and denoise it in the compositor. I have tried using the despeckle node but I still can't seem to find the right way to do it.

Denoiser is only present in the latest versions of Blender. Enable it at the bottom of renderlayer settings tab.

**added comment as answer

https://blender.stackexchange.com/questions/121118/is-there-a-way-to-make-denoising-work-in-the-cycles-viewport/121120#121120

Possible duplicate of How to avoid noisy renders in Cycles?

The Denoising Feature is only available for rendered images as it takes information from the unrendered scene as well as the pixel data of the rendered image to "guess" the right values of each pixel.
So unfortunately the denoiser isn't available for external images. There are a few compositing solutions available though. Here are some node groups you can use.

Your link seems broken


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Render taking extremely long for only 250 frames
Hi I'm new to blender and have been making car animations. My first render which was only 2 seconds took over 2 hours to render. I thought that might be normal but today my render of only 250 frames has taken over 10 hours and is still not done. I have an i5 processor and a gtx 2060 gpu. Any advice is welcome!

Which render engine are you using?

May there is no space in the RAM to render it. Render tooks a lot of RAM space.

I am using Eevee

Could be anything, look up scene optimization for rendering. Maybe you have too much geometry, or you didn't bake your physics, or it could be a volume which is set to low voxel-wise, or several other things.

How long is a single frame been rendered? In animation rendering, you should minimize the time to 1~10 minute if you are using EEVEE. If the single frame render over 10 min, you should probably check is there any undesired complicated thing blocking your rendering time.


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How to separate all faces
I have a default torus
In edit mode i have duplicate 2 times and select all and Press P key i get 3 option by loose parts and when i click get 3 torus separate in outliner.
But when i select the single torus in edit mode select all the faces and hit P key and select loose parts and nothing happens. Here im not getting all the faces separate like the torus separated above.
How can i get separate loose faces. Is there any addon or how can i get all 576 faces separate.

your single torus faces are not separated but connected. Thus they are not "loose parts". It seems you wish a way to get separate faces from an object made of connected faces... right? Your multi torus example doesn't help me to understand... tried selecting all faces then ctrl-e > edge split?

@m.ardito how to separate all the faces attach to the torus. Like we separate if we have multiple cube array and then if we need to loose we separate how to separate the torus face. I need all the 576 faces to be separate in outliner. so that i link and add mesh and then join

Add an edge split modifier, set the angle to 0 and apply the modifier. Then you can select all the faces in edit mode and P separate by loose parts.

You can avoid the modifier step: as said above in comments,

in edit mode, select all faces
then use CTRLE to split all edges

now all faces are unconnected (note the vertices/edges count increased)
then select all and press P to split by "loose parts"

now you have an indipendent object for each face

Thats cool both the answer much satisfied but i have to give any 1 answer tick mark. Thanks for the reply.


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Blender 2.91.0 Broken Material in Material Mode and Render Mode?
thanks for checking in.
So I was making this in Blender 2.91.0
But when I go to Material Mode, it becomes like this:
If I rotate the camera while in Material Mode, it becomes this, the background leak into the model or something:
The material is the default material. I made a new one but it's still the same. Changing the properties don't do anything. And this is how it looks like in Render Mode:
And the render result:
I'm using AMD Radeon RX 570 for VGA with driver version 20.12.1, does that mean anything?
I haven't use Blender for texturing since I got this computer, so I don't know when was the last time it worked. Before I changed computer though, it work just fine.
I've tried reinstalling Blender, redownloading, repairing, nothing fix it.
Anyone know what's wrong?
Thank you.
u.u

The latest AMD drivers are not working properly with blender, rolling back to the previous version seems to work.

Oke, I'll try. Any specific version that is sure to work?

The problem versions are Adrenalin 2020 Edition 20.11.2 and 20.11.3 - presumably anything other than those should be fine.

Okay, I'm downloading 20.11.1 now.

Rolling back to Version 20.11.1 works!
Thanks, guys!
n0n/

The problem is the VGA driver.
I rolled back to version 20.11.1 and it worked.
I downloaded here:
https://www.amd.com/en/support/previous-drivers/graphics/radeon-500-series/radeon-rx-500-series/radeon-rx-570


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Blocky smoke simulation doesn't change shape or makes a dark flash
I've been trying to make several smokes simuations.
I'always end up with 2 types of results :

1st one  is this strange compact & blocky  smoke that never change it's shape even if going upward....

what my smoke look's like

I've tried a few things to stop but nothing's working, changing resolution division or particle emmiter scale etc, standing still...

Or, but still rare, that my smoke do not form anything, but when my frames are re-looping, make a strange kind of "dark" flash and disappear the next 5 frames....

PS : i'm using Blender 2.9.1 & Cycles render engine.

Problem solved by turning Node Wrangler off, relaunching and baking again... idk why .....


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convert animation nodes data to editable objects?
How to to convert animation nodes result into an object?
For example, I have a project in which I use animation nodes to get final result, but the baked result is only in my computer.
When i try to to render this on network the result would change, so I want to convert it into mesh and render it on a system where animation node is not installed.


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Origin point moves every time I try to select an object
I must have messed up either the 3D cursor or the origin point, as every time I try to click and select, to move the object or rescale, the origin point moves along with my mouse wherever I click?

in the top right of your 3D view > Options > disable Affect Only > Origins

Here's how to take screenshots https://www.take-a-screenshot.org/mac.html since the ptoto isn't quite readable. For your question, maybe try to change pivot point by pressing dot on the keyboard > choose Median Point there. If it doesn't help [edit] the question with more screenshots of the problem

I am pretty sure you're using the Cursor tool (red) instead of the Select Box tool (green). Switch to that one and let me know if everything works.

Note that the 3D cursor and the Origin of an object are different things.
The 3D cursor determines the point in which objects are created in the 3D environment. Read:
https://docs.blender.org/manual/en/latest/editors/3dview/3d_cursor.html?highlight=cursor
The Origin of an object is the pivot point where the object rotates.
Read: https://docs.blender.org/manual/en/latest/scene_layout/object/origin.html?highlight=origin


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How can I navigate the viewport using Python?
Normally, with most actions that you want to script with Python there is a pop-up tooltip that shows you the function that you want to use.  However, for viewport navigation there are no pop-ups, you use the mouse directly for everything (scrolling to zoom, middle-click-and-drag to pan).  How can I navigate the viewport with Python?

Why would you want to do this?

@iKlsR, I am working on developing a small addon that allows you to use basic Blender functions through a gamepad or joystick.  Plus, this could be useful to others in the future, as the method of accessing the viewport through Python is not readily apparent.

I would suggest not to call operators at all, these are rather cumbersome way to interact with the view, Instead manipulate the view directly.
If you write an operator you can access the viewport like this...
v3d = context.space_data
rv3d = v3d.region_3d
rv3d.view_location.x += 1.0

You may also want to treat the view as a 4x4 matrix since in some cases this is more convenient since you can multiply it with other matrices to combine transformations, accessible from the view_matrix.
See RegionView3D API docs
To get started you may want to try things out in the python console...
For this you need to specify the absolute path to the 3D region.
In the Scripting screen layout you can run this from the console or editor...
rv3d = bpy.context.screen.areas[2].spaces[0].region_3d
rv3d.view_rotation.rotate(Euler((0, 0, 0.1)))
rv3d.view_location.x += 1.0
rv3d.view_distance -= 1.0

We have a template of an operator that edits the view in the text editor Operator Modal View3D

Could you show how to bring this into newer versions of blender?

Hover over the menu items, the options/commands are there, Go to the 3d view header then View → Navigation. You can hover over a menu item and use Ctrl + C to copy the command to your clipboard.

For example, to pan to the right, you can use bpy.ops.view3d.view_pan(type='PANRIGHT') and to zoom out you can use bpy.ops.view3d.zoom(delta=-1).
I don't think you will be able to move very naturally however, not quite in the way you want to at least.


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How can I pause a render in progress and then resume it at a later time?
I would like to pause a render that I have started, with the intention of resuming it at a later time (but during the same Blender session).  How can I do this?

Are you talking about an animation, or a single picture?

@KyleWilley, mostly a single picture, although if I could get a method for an animation as well that would be nice.

Animations can be paused just by clicking the X on the render, then setting the start frame to the last completed frame. CharlesL wrote an answer that covers this.

Blender Internal and Cycles lack such functionality (but we'd love to have that for Renderfarm.fi)

I'm not tech guy but if is used tile rendering there could be chance to resuming rendering from last finished tile theroretically

Yes, theoretically. But the functionality itself doesn't exist (as in pause and resume buttons, without further need for user interaction).

This could be implemented, hypothetically, by saving the data of the scene, then continuing with samples. AFAIK this could happen easily between samples by saving the image and the random seed parameters the raytracer uses.

@jesterKing, just a small note, avoid excessive self-promotion (not coming down on you, and I appreciate your work, but on SE self-promotion can be frowned upon).

Doesn't Renderfarm.fi render at lower sample counts with various seeds? If so, could you stop after rendering the current seed, and then resume later? You would still have to wait for that seed to finish.

On Mac OS it is not necessary to have started Blender from the command line.  You may use the "kill" command to send a stop and continue signal...
$ ps -ax | grep Blender
3554 ??       750:42.18 /.../.../Contents/MacOS/Blender
$ kill -s SIGSTOP 3554
$ kill -s SIGCONT 3554

There is a way to 'pause' Blender (or any software for that matter), but it relies on the operating system rather than Blender itself.
Mac OS X and Linux:

You must start Blender from the command line or terminal.
At any time, you can completely suspend Blender by pressing Ctrl+Z from the terminal window.
The terminal should say something like:
^Z
[1]+  Stopped                 /Applications/blender.app/Contents/MacOS/blender

You cannot interact with it until you you type fg in the terminal. Which will bring Blender back to the foreground.

Windows:

Have the console window open (Window > Toggle System Console)
Use the cursor to highlight any of the text in this window will freeze the console and pause Blender. This is a super hacky way to actually pause Blender, but it works in a pinch. See https://stackoverflow.com/questions/30418886/how-and-why-does-quickedit-mode-in-command-prompt-freeze-applications for detailed explanation of why this happens.

Great tip! I always used this to simply kill the application, can't believe this was there all along.

Ah, if we go the OS way, then you can get the Process Explorer from http://technet.microsoft.com/en-us/sysinternals and suspend your Blender process using that.

There's no need to start Blender from the terminal. You can simply send the signals to the process. kill -s SIGSTOP $(pidof blender) to stop it and use -s SIGCONT to resume it. On KDE you can do this using the system activities(Ctrl+Esc).

Linux option works like a charm. Windows version does not work anymore.

This does work.  Just tried it with v2.91.  It doesn't pause immediately.  But it will pause at the end of the currently rendered frame.

Pausing from the Operating System:
Linux
If you are on Linux
you can send signals with these commands:
# To pause Blender:
killall -s STOP blender

# To start it again:
killall -s CONT blender

Some advantages to this are that it will work
for any task, not just rendering, and that you
do not have to start blender from a terminal.
For Mac, omit -s and use Blender, not blender.
Windows
You can use process explorer for this. See this question on StackOverflow.
Pausing from Blender:
Pausing F12 renders from Blender is not implemented yet,
however it is on the Cycles Todo List.

I tested this on OS X and it seems that -s does something else, like simulates what would be done or something (see man killall). And omitting -s just causes Blender to be killed. I did have success with the method Mike Pan suggested though.

On Windows, you can use built-in functionality instead, with Resource Monitor > RMB menu > Suspend Process (from the same SO thread).

On mac, you can use killall -STOP blender and killall -CONT blender

On Linux (Ubuntu) you can also stop and resume a process:

On Linux (Ubuntu) you can also stop and resume a process using System Monitor: Tap Super (windows) key once, and type "process" or "system", and choose the "System Monitor" icon. Then in the "Processes" tab right-click the blender entry and choose "Stop". When you want it to resume do the same thing, but choose "Continue". The command line is easier of course... but only if you can remember what to type. :) Sorry for double post. Can't edit a comment after 5 mins? What rubbish is that? ;P

Mixing Smaller Renders
For a still image, a possible solution is to render
less samples multiple times with the seed changed each time, and mix
the images according to the samples. For example:
You have a scene which you would like to render at 3000 samples.

First night you render 1000 samples with seed 0.
Second night you render 1000 samples with seed 1.
Third night you render 500 samples with seed 2.
Fourth night you render 500 samples with seed 3.

The you take an image editor and put these images as layers:

First render: alpha 0.33
Second render: alpha 0.5
Third render: alpha 0.5
Fourth render: alpha 1.0

Each layer's alpha is: current samples /
(all layers samples below + current samples)
5 samples:

15 samples:

Mixed image:

Added Note
As mentioned in the comments: The resulted image may have a slight light-loss compared to the full sampled image, however will also have less noise. You get (almost, very near, way below significance) the same result as using Clamp Direct and Clamp Indirect with the number of samples of the individual renders. So this light-loss will be the same as if you were to set Clamping to 100 for example, which is usually very small. When the Clamp values are already set and lower than the samples, then no additional light-loss should occur.
We discussed this topic in the comment section of some old blog posts, it might be worth reading them:
https://sinmantyx.wordpress.com/2015/02/21/grave-of-the-blender-fireflies/
https://sinmantyx.wordpress.com/2015/03/18/perfect-clamp-1/
https://sinmantyx.wordpress.com/2015/03/18/perfect-clamp-2/

Does this give you exactly the same result as if you had used higher samples in the first place or just an approximation?

Short answere: Only an approximation. Longer one: You get (almost, very near, way below significance) the same result as using "clamp direct" and "clamp idirect" with the number of samples of the individual renders (if these values are already set and lower, then no difference). So the light loss will be the same as if you would set claming to 100 for example.

If you are more interested, look at the end of my edit.

For one frame you could try to use border select then render. You could render parts of your image you need and mix the layers later in GIMP. I use it whenever I add details to a model and don't want to render the whole scene again.

You certainly can break up a render into parts this way (on Renderfarm.fi we use this to split workload between nodes), but it is quite a labour intensive way to do things if you don't have a good automation behind it (Renderfarm.fi has a Tomcat7 servlet running doing all this delegation and stitching).
You can add that for Cycles you could render in batches of ie. 10 or 50 samples, and then average the results all into one (which I implemented on Renderfarm.fi as well ;) Just take care that each batch is rendered with a different seeds

A python script to do stuff like this would be awesome. (I think i'm going to try and learn python now) but to able to define different numbers of samples for different parts of the render... :D

You can pause viewport rendering in Cycles (but not 'Render' menu rendering) by pressing the pause button in the bottom right-hand corner of the 3D view.

If you're rendering an animation, render out the frames individually as PNGs first. If do so, you can stop rendering a frame and come back to render the rest later without any corruption. Once you want the animation as a video file, load the PNGs as an image strip in Blender's video editor and render the video out(it will be really fast because it's just sticking the images together).

Will this just stick the PNGs together into a movie without doing any compression, or will it compress them using the methods of whatever format you are using (Theora, MPEG, etc)?

It'll be compressed using whichever format you decide to use.

For animations that output to a sequence of individual image files an important checkbox is the Overwrite checkbox in the Output subtab of the Render tab of the Properties window.  It defaults to checked.  If you uncheck that box you can interrupt a render, shut down your laptop, turn it back on, and click the render animation button and it will not overwrite the frames that have already been stored to the directory, instead starting calculations at the first missing frame.
A drawback is that if you change the scene and want to discard the rendered frames containing stale data, you have to delete them from the directory some other way (using windows explorer, or linux rm)
Another drawback is that blender's default output directory is /tmp, which some flavors of linux wipe clean every time you reboot the computer.  I use /var/tmp/blender/projectname/ instead.

you can also manually set the start frame to the frame after the last one which was rendered in the previous session when you resume the render, then you don't need to uncheck the overwrite button

Here is how I learned how to do it. In the properties go to  render tab, scroll down to output; in the file format,(default is ffmpegvideo) select png. After selecting png, create new folder, name it and select accept at the top right. Now render the image or animation.
  Now to the pause. If you open the new folder on your computer you can see each image being rendered one at a time.
  If for example you have an animation 240 frames and around the twenty fourth frame you want to stop or pause. Just let the twenty fourth frame finish rendering and click the escape tab on the keyboard twice.  All rendering has stopped.
  You can now close blender, and continue render later.
When you are ready to continue rendering, open the folder animation is saved in, you should be able to see the last frame that was rendered.
So if the last frame rendered was twenty four, go the the timeline in blender and set start frame to twenty five, and then render.
 It should continue rendering from frame twenty five. Here is a tutorial that helped me.  https://www.youtube.com/watch?v=GviUB3irccI

I have been working on a solution, it's a workaround that uses Windows suspend thread function in c++ to pause/unpause blender, but it also minimizes blender in the taskbar in a tray icon, because windows will throw out "Blender has stopped working" if you suspend it and the window still maxmized, it supports Windows 64bit and blender 2.79 https://gum.co/bpupp , support for other platforms coming soon

there is a very fast and easier way , Just set the start frame, then the end frame , and when you want to pause it , just change the end frame to the one currently rendering and then set the start frame to the last frame you render , and repeat.


text:
How may I create a continuously looping animation?
I would like to create a continuously looping animation that repeats itself constantly and without my help (I do not want to create one animation and then copy and paste it over and over again).  A good example would be the rotational movement of a helicopter's blades.  I am not repulsed by a scripting solution, and would indeed welcome it.  How may I accomplish this?

To do this, you'll want to add a Cyclic F-modifier. Go into the Graph Editor and select the keyframes that you wish to loop over (over their respective time period), press Shift + E, and select "Make Cyclic (F-modifier)".

Is it possible to limit the number of loops? For example, what if I want it to be repeated only three times?

You can do this by adding a Cycle F-modifier to the desired F-Curve. After adding the modifier, if you want it to have continuous motion, and not simply start over each time, you'll need to set Repeat with offset.

You can use the NLA editor to make a repeating animation.
Changing the repeat value will change how many times the animation will repeat. Just make sure your animation was converted to an NLA strip otherwise you won't be able to repeat the track.

So how to you " Just make sure your animation was converted to an NLA"

This is by far the best and easiest answer. Messing around with the graph editor is a pain.

Upvoted because the NLA is far more powerful and flexible for this purpose. The Cyclic Modifier is only really useful if the object repeats the animation throughout the scene.


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How to easily identify which nodes have logic bricks attached to them in the outliner
I downloaded an .blend file that has a lot of objects listed in the outliner, I wonder how can I find which nodes have logic bricks attached, because in the logic editor there seems to be no way to do that.

You can run the following in the Text Editor to select all objects in the scene with a logicbrick.
import bpy

bpy.ops.object.select_all(action="DESELECT")
logicbricks = ("controllers", "sensors", "actuators")
for obj in bpy.context.scene.objects:
    if any(len(getattr(obj.game, brick_type)) for brick_type in logicbricks):
        obj.select = True
bpy.context.scene.objects.active = obj

Cool! using your script and showing only the selected objects in the outliner is that I wanted


text:
Subdivide loop at custom position without stretching the texture
How can one subdivide at an arbitrary position, say the cylinder side faces, using CTRL+R (subdivide loop tool), so that the texture is not stretched like this:
Before

After

If this is not possible with this tool, is there another way, like for instance recalculating a group of UV coordinates by means of their vertex position and their surrounding vertices.

The loop cut operator has an option to correct UVs. Enable it in the redo panel, below the tool shelf or with F6:

You could also use the knife tool (K), with angle constrain (C) and cut through (Z):

Wow man! that was fast!, and that GIF video screen capture is awesome.

It's called LICEcap if you want to try it out.

It's only partially related but I want to note for the record that "Inset Faces" also works without distorting the texture mapping - great if you're adding more detail to an already-textured mesh.


text:
How to access/edit information about included audio files?
I have a blend file that is supposed to be packed with a few wav audio files, but it seems the author forgot to pack them, and I don't have the files, if I try the option File>External Data>Pack into blend file blender shows the error:
Unable to pack file, source path '//long path/something.wav' not found
I've found the library where those files were originally downloaded, and downloaded the required files, now I want to edit the information in the blend file so that blender can find those files.

have you tried recreating the directory structure that Blender is looking for?  You have one of them listed in your question.  I'm guessing that the folder "long path" should be next to the .blend

Yes, I ended up re-creating all the directory structure, it seems there is no way to edit those paths directly in blender.

Once you have re-created the directories and blender finds the files you could pack external data so you won't need the external copies any more?

@sambler ok, I did that too, also used the option to convert all paths to relative paths, to remove any sensitive data , but I don't know what that option really does.

Paths are either relative or absolute - relative is directions from the blendfile to the data file. Absolute is an exact location on disk. A new question can expand that.

You can edit the file path of the Sound Datablock (and any external file) using the Outliner:

From the header, make sure the outliner is set to display 'Datablocks'.
Browser to the Sounds section and find the sound datablock you want to edit.
Expand the RNA and modify the File Path string as required.
You might have to restart Blender to force a reload.


text:
How to export the unfolded image I'm seeing in the UV Image Editor as an SVG?
I'm wanting to convert a 3D concave cylinder into a 2D image. I've brought it into Blender as an STL, generated a UV Image, and added a material. Looks good. I'm just learning Blender. So search results seemed to indicate that Paper Model add-in was the way to go to get 3D > 2D > SVG export.
But I can't keep it from unwrapping mesh triangles into a thousand tiny, separate packed islands. When I use Export Paper Model, I don't get what I see in the UV/Image editor: the mesh flattened. Instead, each triangle has been separated out and packed with like kind, each with their own little numbered tabs. This would be really cool for creating paper models. I get that.
But I need bigger islands: I need exactly what I'm seeing in the UV Image Editor screen. Any way I can just export that to SVG?

You can export the UV-Layout as .svg file. In the UV-Editor, go to UV > Export UV Layout. Then select the file format as .svg.

Thanks for this. But I'm not seeing the UV Image menu item. I've updated my question to include a screenshot of my menus. I have an "Image" menu item, but on selecting that, the resulting dialog box does not give an option for SVG. How do I get all the menu items you have?

@theship Right. You have to switch to edit mode in the 3D view and select all vertices. Then the options should appear in the UV Editor.

That'll do it! Thanks much.


text:
Anyone know how to preview Dynamic Paint weight properly in 2.8?
Does anyone know how to 'see' Dynamic Paint in 'weight' mode in Blender 2.8?
I've trawled this link- https://developer.blender.org/T56349
And this looks like how you're supposed to do it-
We have workarounds for displaying previews:
Vertex Paint:

Configure Output Paintmap Layer and or Wetmap Layer
Switch to Mesh Object Data properties tab
Activate Vertex Color
Switch back to Physics properties tab
Activate workbench vertex color type

Weight Paint:

Add material
Configure material to display weights
Switch viewport to Lookdev or rendered mode in EEVEE/Cycles.

I'm interested in the Weight Paint bit- how do you 'Configure material to display weights'?
I've tried an attribute node colour & factor outputs, either direct into a principled BSDF, or via a colour ramp, but see nothing after baking the Dynamic paint.
The DP Weight map seems to bake out, and seems to influence smoke sort of correctly, it doesn't do such a good job with particles (used for density), but that could be my setup, or the fact that I can't 'see' the weight map.
Here's a quick test I tried- https://www.dropbox.com/s/54oht3nvnnxljaa/DP_Weight_2.8_Test01.blend?dl=0
Any help- greatly appreciated...
Edit: It does work for particles if you use Monseiur Merle's method of masking out the DP Weight painted part of the canvas (https://www.youtube.com/watch?v=J313g2N5hZc), then emitting particles from that.
It does not seem to work using the DP Weight map for particle density, like a hand painted weight map will work for particle emission.
Here's a second file showing that- https://www.dropbox.com/s/4cyvqcqgand9ukl/DP_Weight_2.8_Test02.blend?dl=0
Should the DP Weight map work for particle density or do you have to use the mask+weight edit modifier method to get the effect of particles emitting from the weight painted areas only?
Once again, any help greatly appreciated.

On the question: how do you 'Configure material to display weights'? I believe it's coming up in a future build. In the mean time, there's a deeply cunning solution here


text:
How to render a world position pass that includes volumetrics?
I've found the 'how to render a world position pass' Q&A on here, but I'm stuck at how to render one that includes volumetric objects (smoke in a domain object), it does not show in the render layer I setup as per the above answer.
Obviously, as there would need to be a separate shader feeding into the 'volume' input of the material output node, my question is how do you create a WPP shader for volumes? Or more to the point can you create one?
Edit- It looks like you can almost do it, but the smoke gets incorrect / different XYZ-RGB data compared to the meshes. If you look at this video, you can see that in Fusion you can pick 3D/XYZ position from the 2D render, but the smoke isn't in the same 'world' position wise.
https://youtu.be/Ne9J2vyGOS4
The shaders are as follows-

Any ideas? How to get the smoke WPP shader to match the mesh WPP shader position wise?

It looks like it can almost be done-

Looks like (with the help of @iponoo @zeauro & @ kologe from blender artists & blenderchat), it is possible.
Here's the smoke shader, that works with the mesh shader to produce a WPP for both smoke and meshes-

It works well enough for me to do a bit of 'deep' type comping-
https://youtu.be/xgCA-D4ukJk
In the video the smoke seems to be respecting the same XYZ-RGB space as the meshes.
So divide the vectors by 100 in the smoke shader seems to make things all work together.
And certainly work well enough with the 'volume mask' tool in Fusion for me.
Cheers!


text:
Problem using transformation constraints to rotate gears
So, I'm working on a clock and to help me animating it I am using transformation constraints, but when I put it in the third gear it started reversing the rotation after rotating some degrees, going back and forth.

This is what is happening.
I already used transformation constraints before but I never had this problem.
I tried changing the values, activating Extrapolate, reseting the rotations but nothing worked.

https://youtu.be/FSYiDLv2fjw and https://youtu.be/h37WgwkkTFg are the two videos I refer to when doing gears.  O.T. Vinta has several other useful ones as well. In a nutshell you use a hinge Rigid Body Constraint which allows the gear to rotate around the Z axis of the constraint object (an empty).  The gear and the axle are Rigid Bodies; the gear is active, the axle is passive.

i tried using rigid bodies, but for this clock model its not worth it, too heavy for processing and not accurate. thx anyway.

The best way to do these kind of thing is using a combination of armature and Animation Nodes. download this addOn from here.
Do the following:

Add an armatures in the location of each gear and set its rotation
Combine all armatures (so you will have a clean armature for all of
your gears)
Create nodes in animation nodes as explained in the gif file
Link each gear to the corresponding bone.
Done!

I think its more simple using constrains or drivers, but I'll give it a try. thx.

in this way you can have all of your gears in a single node tree. it gives you a cleaner access to all of your gears.

First I think that you were wrong with the settings, and also it looks like you need to apply the rotation of the big wheel (don't ask me why, it must have to see with its local axis of course), then it works:

well, the thing is that I don't want to apply the rotation. I tried to use 'from Local Space to Local Space but it was not working.

yes it's hard to understand, maybe there's a bug in this constraint


text:
Rigging an Umbrella and Weight Paint
I have been trying to weight paint an umbrella to rig bones. However, I haven't been able to resolve the edges furthest away from the bones. They overlap when the umbrella is near closing. I have looked at this post for rigging an umbrella including the weight paint and I have tried to replicate it but I have not been successful. Would be really happy to hear suggestions of how to properly rig an umbrella and/or assign vertex weight paint colors.
link to my rig file: rig file link

Here are screenshots of my current weight painting vertex weights as they are in the screenshots above.

and here are working vertex colors from the link. Although, the umbrella I am working is upside down in normal open position, I don't understand why it doesn't work

I figured it out. The initial mesh cannot be subdivided more than the number of bone ribs. Each vertex should be mapped to a bone. Watching this tutorial on rigging an umbrella in 3ds Max gave me the answer.
I had basically overcomplicated the problem by subdivisions assigned with weights in between the two ribs.
In other words, I have 6 ribs for the umbrella, with 4 bones along the umbrella mesh. Each bone gets mapped to a vertex.


text:
Is it possible to build blender scripts in external editor like Atom
I have little experience scripting thus far but want to develop my skills further. I am particularly interested in autocomplete features and looking to script geometry within one context for Rhino, Blender, and Processing. Atom handles Rhino and processing, but not sure how to make it work with Blender.
Edit: Is it possible to create an atom package for a bpy/bmesh autocomplete library and send scripts directly to blender?
Here is how Atom can be used with Rhino Python:

Scripts can be executed within Atom.

Just to be sure, you're looking for an atom package for a bpy/bmesh autocomplete library?

In theory, one can build blender as a python module, but last I heard it wasn't very good or easy to do. I'm not sure if this can plug into atom just by dropping it into the python module directory or if you'll have to build an autocomplete "dictionary" of sorts. (This is me just thinking out loud, for later research.)

There is a package for sublime: https://github.com/svenfraeys/SublimeBlender

related: http://blender.stackexchange.com/questions/31126/workflow-for-developing-add-on-script

When I was doing this with sublime, I added a "build system" to sublime, essentialy "run this shell code on save", that would run a new headless (or not if directed to) blender instance that ran my script. It was slow but it did allow me to leverage an ide for writing my scripts. It's a bit like setting up a testing framework, and I would recommend additionally setting up a testing framework too so you can know if your script is working and still working without manually, visually inspecting your script results, if possible.

Notably this is just one way you can approach this; Main comments have useful links as well to other setups^


text:
Why can't I create a new face connecting the selected vertices?
As shown in the picture, I've switched on X-ray，selected all vertices and pressed F, but no new face is created.
After that, I switch off X-ray ,selected the vertices again and pressed F, it works.
what is going on?
（Blender Version 2.91.0）

Most likely there are overlapping duplicated vertices. The first image indicates a selection of 48 vertices, the second one 12.
So you should select all A then M to merge and "by distance".

Thanks very much.


text:
How to update my blender without losing all my settings on mac
How do i update to blender 2.91 on Mac
i currently have version 2.83. How do I update to version 2.91 useing Homebrew?
without overwriting

Just copy the startup.blend and the userpref.blend to a different folder, update blender,  and copy the preferences back to the original folder. See How would I import/export Blender's preferences?


text:
Align Grease Pencil with Camera Angle
I placed the camera on a certain position and want to start drawing with the grease pencil, but the lines appears somewhere else. Sure I can move them in front of the camera but I want it to be aligned correctly.
Someone asked here a similar question but it doesn't work for Blender 2.9. anymore.
Attach the grease pencil to the camera
Edit
What I've tried:

I position a new camera and and set it as active camera

set it as active camera and added a blank grease pencil object.

started drawing. looking good for the first impression but

its seems that it's aligned to the first camera

The grease pencil strokes are aligned to the window in which you draw. Strokes will appear in a plane that is perpendicluar to the Z axis of the camera (or to whatever other view you want to draw in).
Here is an example that shows how to draw in camera view (press Numpad 0).

The distance to the camera, in which the grease pencil layer appears, is determined by the placement of the 3D cursor.

Note that the link posted on the question refers to the annotation tool, which is a different tool than the Grease Pencil

well this happens so smoothly because adding a grease pencil automaticly snaps to your camera view. It doesn't happen in my case. Camera is placed and set to active camera. Grease pencil appears in a strange position I cant relate on.

Please show what you get, it is hard to guess what you get, edit your question and show images that illustrate the problem.


text:
Grease Pencil: render is darker than what is displayed in the viewport
2D Animators question:
I have a material with a certain color, but in the rendering it appears a bit darker. See here:

Maybe there is an light or shadow source.
What I've tryed:

deleted  all light objects (see layers)

unchecked "use lights" in the layers properties (see grease pencil properties)

deleted the backround in the world properties

Here are also my render settings (opened up light and shadow settings. is anything else needed?) and

material settings

Please use the [edit] link at the bottom of your post
(https://i.sstatic.net/lXFuK.png) and upload images that show your
current setup and illustrate the problem.
See [How to upload an image to a post?]
(https://meta.stackexchange.com/questions/75491)

Done :) Hope this is more clear now?

my goodness! THANK YOU :D

world properties - viewport display, set it to white, it doesn't make sense, but it works.

Try switching the color management to standard.
As far as I know the grease pencil is hopelessly coded in sRGB, so it will look dark if the color transform is set to filmic.

Related: blender output is greyish and not white

The Grease Pencil Object is reacting to World lighting which is making it darker than normal.
World Lighting can be swithed off by disabling 'Scene World'.

Go to World Properties > Viewport Display, set it to white.
I don't know the technical side, but it seems like 2D render in display mode/space

To fix that, in the Object Data properties tab, uncheck the option Use Lights, and everything should look exactly like it does in the preview.


text:
BGE: Writing text letter by letter
I've seen the new text functions for the BGE and they are wonderful, I wanted so to try to make some zelda like text, writing, letter by letter (and with different speeds, but that's another step).
I just got stuck with the delay in the for cycle for "printing" the letters into the variable.
the classic time.sleep(0.5) freezes the game, so I went back and tried with the pulse of an always sensor. Now I don`t know how to use it.
here is my poor code:
import bge

cont = bge.logic.getCurrentController()
own = cont.owner

time = cont.sensors["Timer"]

def delay_print(s):
    w = ""
    for c in s:
        if time == True:
            w += str(c)
        own.text = w

delay_print("hello world1223456789af2f2rvetbdfb")

own.size = 0.2

This might be interesting, he uses the frame no to simulate a typewriter  http://urchn.org/post/typewriter-blender-addon

Instead of using an always sensor, try a delay sensor to trigger the script. Slow it down by increasing the delay value and check 'repeat'. The text object needs an integer Game Property named 'counter' to work with the script.
import bge
cont = bge.logic.getCurrentController()
own = cont.owner

message = "Don't wish it were easier, wish you were better!"
mlen = len(message) # length of the string

if own['counter'] < mlen :
    own['counter'] += 1
    own.text = message[0 : own['counter']] # slice indices


text:
How to: 2 Bvh files, 1 model
I have a model. I would like it to have 2 different animations standing upright, and both facing forward in the animation library. How do I do that?
I am using makehuman, blender 2.78, makewalk and fragmotion and bvh hacker. And some x , y , Z things keep getting mixed up when importing to and from the diffrent programs and it also screws with animations.
Can someone please send me this model back all set up and tell me how they did that?
I know it sounds quite simple, but it turned out to be difficult. I would like someone to send the file back so i know it can be done.
Blender seems to be incapable of doing what I am attempting to do. Which is sad I Like this program.
Model
bvh file 1
bvh file 2


text:
Cannot Apply Vertex Groups To Bones
im Francisco and i have a problem with vertex Groups. Recently i modeled a star wars spaceship witch is called millenium falcon and after i model everything i started rigging , while i was rigging i was watching a couple of tutorials and non of them worked for me. My problem is the following one, in the spaceship i modeled every part separated from each other and i dont know how toenter image description here rig them all together, i tried to do ctrl+j to join everything but my mesh is a bit confusing in terms of faces... pls if you can help i desperately call for help , i always stay stuck in here.

Here is the file for download
https://drive.google.com/file/d/1VphWxqtiQcmYKdl-guGSfWPxOohqTp8L/view?usp=sharing

My guess would be that you have not applied Location and Scale on the parts that you are trying to rig. Try that with Ctrl + A when you have the parts selected. Your transform Values should read all zeroes for position and ones for scale.

Also, upload the .blend file, it might be helpful to properly diagnose your troubles.

ive maded the upload just now

Ok, your problem is simple.

The reason your vertex groups do not take is, that you applied them all on the main hull of the ship. If your ship pieces are still separate objects, the vertex groups for the bone influences need to be on THAT object.
For your ship, you won't need to create them by hand. Parenting to Bones will do it for you.
Clear up your parenting structure, so one object does not move the other. Just hit Alt + P to clear Parents with "Clear and keep Transformation"
You need to apply the transformations to the objects, that you made in Object Mode. Your Location Values should be zeroed out, the scales should be at one.

Select Bone in Pose Mode

Click on Geometry you want the Bone to be the Parent of

Shift-Select the Armature again

Ctrl + P to Parent the Geometry to the Selected Bone
Selecting one bone of the armature (in Pose Mode), like for example the one that controls the landing gear, you select the mesh you want to attach to it to, Shift Select the Armature again and then hit Ctrl + P and Parent to Bone.
I have done this for you in the blend file. I would also advise you to roll your bones over, so that all hatches close by rotating the x-axis, just to give an example. That will allow you to lock the other transform channels. Otherwise, you will go nuts animating.
I have also set your rotation to ZYX Euler. Since the hatches only rotate around a single axis, that will make everything easier, transforming, reading and changing the animation curves, locking the right channels. Try it, you will see it right away.


text:
Transform (Rotate) with 4x4 matrix via python
I have imported geometry that I am rigging for showing assembly of a product. The driving curves have been imported from rhino, from which I have built up the model further in Blender.
As part of the animation, I would like to show how all the parts fit in a box, when they are flat. However, rotating each part by eye is proving difficult as each part is quite 3 dimensional. Thus, via Rhino, I have calculated the transform matrix needed for each part in order for it to be flat on the ground.
I would like to use the data from this matrix to transform objects via python.

Update: Here is a simplified version:
, where the orange is the target.
Here is the output that I get from Rhnio python going from A to A':
R0=(-0.470458022353494,-0.807963312121372,0.354773921630525,-6631.4567921258), R1=(0.645229984870226,-0.589232780440685,-0.486295174846007,3943.31281557432), R2=(0.601953084407421,0.000129305847915359,0.798531444247745,2890.46728702281), R3=(0,0,0,1)
I make the following output into a python list and then set it to the updated matrix from above
import bpy
from mathutils import Matrix, Vector

obj = bpy.data.objects['Untitled'].pose.bones["topfrontleft"]

m =  (0.879972675860339,-0.0926548147745,0.465900391755896,-1329.45963312555), (0.443132751289856,-0.193193761313235,-0.875391075647866,1124.19004435354),(0.171118247050034,0.976775949687925,-0.128946848111055,3977.30420903923),(0,0,0,1)

m_new = Matrix(m)

obj.matrix = m_new

Here is a ling to the Blend file: http://1drv.ms/1X8vHXO

I see you using Grasshopper?, you may be interested in Blender's equivalent Sverchok

Yes, I have dabbled with it, however in this case, I need to transform bones. To my knowledge, sverchok seems to be only for meshes. I also work with curve tools within animation Nodes. However Animation nodes is limited to a 3x3 matrix and I am not sure how to input the 4x4 data from gh into Animation Nodes

I found out how to perform matrix operations via pythoon with a 4x4 matrix, with the values I got from Rhino/Python. However in the blender console, it says that results may not be what is expected if the matrix is not unitized. However, I am not sure how to unitize it, in either Rhino/Python or Blender/Python

What line of code produces the warning message?

Why do you think that Animation Nodes is limited to 3x3 matrices? In fact every time you use the matrix socket you will have a 4x4 matrix.

@JacquesLucke I would love to see how it would be possible to achieve this with a sample information in the linked blend file above.

@batFINGER, I have updated the question with the python code that I am using at the moment and the blend file with the geometry

I took your blend file and modified the code a little bit. At first I inserted the R0, R1, R2 and R3 values into the matrix. Then to transform a given matrix with another one you have to multiply them. The order is important.
import bpy
from mathutils import Matrix

bone = bpy.data.objects['Untitled'].pose.bones["topfrontleft"]

m = [ (-0.470458022353494, -0.807963312121372,     0.354773921630525, -6631.4567921258),
      ( 0.645229984870226, -0.589232780440685,    -0.486295174846007,  3943.31281557432),
      ( 0.601953084407421,  0.000129305847915359,  0.798531444247745,  2890.46728702281),
      ( 0,                  0,                     0,                  1) ]

matrix = Matrix(m)
bone.matrix = matrix * bone.matrix

After executing the code in your file the bone is 'flat', but instead of being parallel to the x axis (so that it matches the other edge) it is parallel to the y axis.. Are you sure that the matrix is correct? If yes you will need some other matrices to rotate it in the correct direction, but at least it's already flat :D

Amazing. Thank you, Jacques! I did some plane rotation in Rhino, which is why i have the feeling that it is aligned to a different position. As this has been the first occassion working with matrices, I am still trying to wrap my head around the concept. Could you explain why the new matrix has to be multiplied with the old in order for it to work?

FYI: here is the correct matrix. m = (0.645229984870226,-0.589232780440685,-0.486295174846007,187.679183422907), (0.470458022353494,0.807963312121372,-0.354773921630525,2875.82315997439), (0.601953084407421,0.000129305847915359,0.798531444247745,2890.46728702281), (0,0,0,1). Also, wondering if this kind of transform orientation can be achieved solely in blender?

Hm explaining that in detail is a bit complicated and to be honest I also don't know too much about them.. Some time ago I created this video: https://www.youtube.com/watch?v=EWkK11PQG_Y&list=PLFSQhJg6cGLIZwDpScK1v1m1NSZnrCTQN&index=8
Maybe it helps you to understand how matrices work. Note: The combine matrices node in the Animation Nodes just multiplys the matrices. (But in reverse order so that it is easier to work with them as an artist.)


text:
How to orient objects to face towards another object in geometry nodes
I have set up a particle system based on a group of people that I would like to face towards a target.
I know I can play with the rotation of the whole system and randomize, but global rotation doesn't quite work if the target were to be in the center of the particle system.
Also, I know that I can bake the particles and add a track-to-constraint, but baking thousands of high poly meshes would make the file unusable. So, looking to see if there is a way to keep the particle system and orient towards a target.
Edit: With geometry nodes this has become significantly easier. See  answer below

"I know that I can bake the particles and add a track-to-constraint, but baking thousands of high poly meshes would make the file unusable" What do you mean "bake" the particles? You can make duplicates real, keeping instances, and it shouldn't be much heavier than the current setup, while allowing adding the necessary constraint. That sounds like the way to go

I mean converting the particle system to real geometry. They share mesh data, but in my experience Blender doesn't handle thousands of objects well. Once I do bake, I have thousands of objects and blender slows down significantly. It's not usable for the number of particles I am working with - 7000-15,000.

Maybe have a look at crowdmaster or animation nodes

Thanks @sambler for the suggestion. I've looked into crowdmaster, but it looks quite complicated, and it doesn't rely on a particle system, meaning that if there are thousands of objects, Blender significantly slows down

With Geometry Nodes, having instances that face a particular object like an empty has become significantly easier. Here is the setup

Use a Force Field:
Hair particles, even without using dynamics, follow the force fields:

In the Viewport do Add > Force Field (type "Force"). Place it where you need it to be. From the Physics properties panel, set the force to a negative value and leave the rest as it is.
The internal rotation of the base hair particle (humans) must be adjusted to make sure that the correct side points to the Force Field. In my case this is the mesh used:

Note that the "face" is looking towards negative Z, while the "head" is "up" in the direction of positive Y. The correct rotation must either be achieved in edit mode or obtained in object mode and then applied (CtrlA > Rotation)
You need neither the "Advanced" setting on Emission, nor the "Rotation" extra settings.


text:
Mask not matching the image
I made a video and created a mask around my mouth. The problem I have is that in the output of the compositor the mask is not matching the mouth like it is in the movie clip editor of the Masking tab.
Here is the Mask editor view

And here is the output of the compositing (pointed by red arrow). The mask is bigger than the source video used to create the mask.

Is the video clip the same size as the output dimensions for the project? Is the resolution set to 100%?

@susu yes, you are right. I fixed the issue by adding a scale node on the movie clip set on render size and it solve the problem. The reason is that the mask created in the Masking tab is done in the context of render size and not the input movie dimensions. Thanks again for your advise

Does this answer your question? Irregular mask size compositor vs movie clip editor and why is the mask size mismatched in the compositor?

how can I resize the canvas of an image in the compositor?


text:
Dope sheet editor. What does the orange line between keyframes mean?
I start to use the dope sheet view to see my key frames. But I don't understand why for some I have an orange line and not for others like below. What is the meaning of the orange line between keyframe?

See: make a keyframe last longer than one frame

Those orange lines represent a hold: the selected keyframes at each end have the same value, so there is no transformation in between them.
For example:

For unselected keyframes the line connecting equal keyframes will be displayed in gray.


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How can I fix this "relpath" error
I'm trying to use node wrangler for image textures and when I tried to use it I got this error. I have the textures on my main drive and the save file of the project on a different file if that helps explain anything. How can I fix this error?
I tried moving everything to the same drive and that didn't fix it.

It looks like you are using relative paths but the files are in different drives. Move all the files to a common directory, where the project file is, or use absolute paths, so that the files are in a fixed location

That fixed it! Just had to click off relative paths so it was unchecked..

It looks like you are using relative paths but the files are in different drives and not in the folder where the project file is. Move all the files to a common directory, along with the project file, or disable relative paths, so that the files are in a fixed location.
From the blender manual:

Relative Paths
Many blend-files reference external images or other linked blend-files. A path tells Blender where to look for these files. If the external files are moved, the blend-file that references them will not look right.
When you specify one of these external files, the default option is to make the path relative. Blender stores a partial path evaluated relative to the directory location of the referencing blend-file. This choice helps when you need to reorganize folders or move your files.
With a relative path, you can move the blend-file to a new location provided the externally linked files are moved along with it. For example, you could send someone a folder that contains a blend-file and a sub-folder of external images that it references.
When relative paths are supported, the File Browser provides a Relative Path checkbox, when entering the path into a text field, use a double slash prefix (//) to make it so.


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Shadow catcher plane transparency problem in compositing
I'm new to blender and need some help with compositing. I tracked a video footage to camera solve and placed a 3d car in compositing. Shadow catcher plane showing world background on my footage floor under the car instead of showing shadow on floor. Shadow catcher plane is casting shadows but cropping my footage floor where shadow catcher plane is placed.

I'm sorry I can't follow... could you show some screenshots to clarify? What means the shadow catcher plane shows the world background on the footage floor? With footage floor you mean the floor which is seen in the footage? And the shadow catcher plane casts shadows onto what? Just a quick guess from me: in the Visibility > Mask settings of the shadow catcher plane, where Shadow Catcher is enabled, is there also Holdout checked? It sounds a bit like that if I understand it correctly.

yes you got it right. Footage floor where I am trying to place 3d car is suppose to have shadow under the car, but the shadow catcher plane is showing world HDR through that plane shape also casting shadow on that. and no holdout is unchecked.

So your scene consists of the car and the shadow catcher plane. And how do you get your footage into the scene?

by movie clip editor and then camera tracked. I tried so many things but nothing worked.

No, I mean in the compositing. How do you get your movie clip to be rendered under the car and shadow plane? With an Image Texture node and Alpha Over node, or do you have an object in your scene with the movie clip as texture? Maybe it would be best to upload a file with your setup or at least show screenshots. To upload a file take this link: https://blend-exchange.giantcowfilms.com/

its a movie clip node to undistortion node and then scale node to 2 alpha over nodes. Don't know much about nodes, still learning. project is uploading.

With the screenshot it's a lot easier. Do you render your scene with a visible background? Then I might have an answer.

Please don't delete the images and links on the question, without them the question is not clear. Think that other users that have the same issue can use your question to solve their problem too.

To alpha over your rendered car and shadow above your footage, the background needs to be transparent. Go to Render Settings > Film > Transparent and enable it.

By the way, to ensure that the plane catches the complete shadow and it's not cut off somewhere giving a sharp border, I would suggest you make the plane a lot bigger. Since it's invisible it won't make a difference for the result (as long as the shadow is projected onto the floor, not the other car or anything else that's not lying flat under it).

God bless you..Problem solved. :) Thank you so so much


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Object not showing correctly on camera or view but it renders
Suddenly, after trying some weird effects, shadings and deleting them, my object started displaying in the viewport as only mesh, disappearing in the camera but still renders completely fine.
I can't do further work without previewing.
Any guess on this?

Edit: For clarification, this is the normal Animation view,  I didn't change anything from the default windows organization.
Also I'll include another screenshot for you to see that it's not about the object position or anything.

Is the left side of the screen the rendered view seen through the camera? Just a guess because it's hard to tell if there are any settings wrong, but in the 3D viewport on the right side it looks like the camera is behind the objects and therefore needs to be either  looking in the opposite direction or move backwards to have the text in front again. //EDIT: Forget that, I guess than they wouldn't render in front of the camera. But on the other hand, the rendered frame is #173, the current view is at frame #1 and the text object is animated. Maybe the camera can't "see" the text on frame #1?

It's not that, and the windows are the default ones, I'm pretty noob at this so I didn't change any window organization, it's the default animation tab window config.
I added another screenshot so you can tell it's not the keyframe position
Thanks in advance

Maybe you have accidentally deactivated something in the Object Types Visibility settings in the left 3D Viewport, for example Mesh or Text or anything else which applies to your text object. In this case it won't be displayed in the viewport but renders normal.


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Subdivision surface modifier creating lines and stretches on imported SVG
I am having a lot of trouble with just smoothing out a mesh.
I created an organic outline through Adobe Illustrator and imported it as an SVG to blender.
I converted it to a mesh, extruded it, and I basically just want to smooth it out (It's supposed to be a duck foot).
Once the modifier is added, it looks like this

and has all these lines and stretches which obviously also affects the texture.
I have also used 'limited dissolve' to get rid of a lot of the vertices, but this still make much of a difference.

Hello Catherine :). The weird shading might be caused by n-gons created during import and dissolving. Please add a wireframe view and perhaps share the file: https://pasteall.org/blend/

basically for subsurf to work good on that object you'd need to make retopology. Geometry of the mesh isn't visible on screenshots but if vertices aren't too tight you can try to inset top and bottom faces and call it a day, though it's a dirty workaround. Other than that maybe try this addon for generating better geometry

Your outline is jagged itself, And why subdiv? And another idea is to set the outline's edges Edge Mean Crease = 1.

The subsurface modifier can be a tricky modifier to learn.
Basically, all it does is apply a "blend" between 3 consecutive edges. Sounds simple but getting a grip on how this works can be challenging at first.
We uses "control" loops to control the blending. Take a basic cube for example. Adding a SubD modifier to it blends the edges from one, across the faces, through the next edge and around to another, and it does this 3 dimensionally, effectively making a sphere.

If we add a "control loop" it gives another set of edges for the algorithm to use which tightens up the smoothing. The closer the control loop gets to other edges, the tighter the blending becomes as the 3 edges it is blending between become closer together. As this control loop moves it gives us control over the blending.

Then a second control loop adds more complexity tightening up the corners.

The more complex the surface the more complex this becomes.
Then there is the "crease edge" part to SubD. Adding a crease to an edge tells Blender to ignore this edge in the SubD modifier.

This is a very simple example, but you need to understand the basics of how it works before you can use it in more complex situations.
Your particular mesh looks like it's lacking controlling edges, it's a mess of edges so as Blender tries to blend between 3 edges there is other edges telling it to try and blend in a different direction creating a mess. Your best bet is to use a remesh modifier on it. As it's fairly simple, try the QuadriFlow remesh tool. This tool is very CPU intensive, so use it with low settings at first, then bump it up until you're happy.


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Restore last windows arrangement in single/multi-monitor setup
I would like to get the windows that I left open the last time I worked in Blender, either in single or multi-monitor settings.
How can it be done?

The panel layout saves automatically when you save the file. Do you mean for new files?

@CharlesL For instance I use the user preferences window for the properties or the outliner too, and both windows are in separate monitors, I woul like to see the same arragment when I open Blender, either in a new file or in a pre-existing one

Hmm... I'm not sure about multiple windows. I know it works on layouts. As for the user preferences, there's an add-on called QuickPrefs that allows you to change many options in the properties panel.

As CharlesL pointed out, the UI layout is saved in the .blend file.

Setup your windows as desired.
File > Save Startup File (shortcut Ctrl + U).

When loading files uncheck the Load UI option to prevent the layout changing. This can be made the default by disabling said setting under the User Preferences > File tab (shortcut Ctrl + Alt + U).

do you know if this is platform dependent? it kind of works but all the windows open in the main monitor instead of keeping the last arrangement

I can't currently test this behaviour (single monitor). Sounds like you should submit a bug report.

On linux and windows-xp it restores windows correctly on 2-3 monitor setups, we have a bug in the tracker that reports troubles with windows-7 http://projects.blender.org/tracker/index.php?func=detail&aid=34962&group_id=9&atid=498


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Export bullet physics with the Y and Z axis swapped
I'm using the script example used in Blender's physics documentation:
import PhysicsConstraints
PhysicsConstraints.exportBulletFile("Physics.bullet")

The problem is that the Y and Z axis appear to be swapped when the data is loaded at runtime by a third party game engine. Is there a way to swap the coordinates before exporting to the .bullet file?
Can this swapping be automated in the script?
A video showing how the script is used
As a side note, the bullet exporter is not an add-on exporter, but rather a feature of the physics engine module.

Is this a Blender library? Would you mind linking to it?

@CharlesL http://wiki.blender.org/index.php/Doc:2.6/Manual/Game_Engine/Physics

according this post Is it possible to make Blender a Y-up world?
not really, though most exporters have an option to flip it.

Bullet exporter is not an add-on exporter, but rather a feature of the physics engine module

@rraallvv it would be more useful for you to add this information to your question.


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How to close/open a view panel
I can't find a way to close a view panel, in particular the horizontal at the bottom, is pretty useless to me at this moment.

Why would you ever want to close the logic editor? I overwrote the start up file to have that in it!

@X-27 that was almost two years ago when I started using blender, at that moment I was using it only as a 3d modelling tool

That is the Logic Editor at the bottom, (you probably opened it accidentally as it's not normally in the Default scene as you have it). In your case here, look in the corner of the panel where the little lines are.. (these are called the viewport handles and are always in the upper top-right or lower bottom-left).

Left click the handle and drag down, an arrow will overlay the view as a sort of confirmation, just drag it down and it will 'close' that view.
Likewise, the process to open one is the same. You can also create new windows with these, Just Shift click on the handles in either corner and drag it to 'tear' it out that view into its own window. (this just makes a copy of that view in its own window, the original stays the same)
NB: A good point to further note is that to expand or collapse a view into another. They must be of the same width or height. Meaning, if the top has two views and the bottom has one wide one, you wouldn't be able to expand the bottom one.

Also if you happened to take the one in the very bottom left hand corner and drag up it would give you a arrow to prompt and see if you wanted to close your 3d view (in this case) but if you don't want to close your 3d view, you can drag it back into the (in this case) game logic panel it would close the game logic panel instead

@gandalf3 actually no. Dragging up from the bottom left creates a duplicate of that view. I think you mean upper right?

@iKlsR I think he meant "upper right hand corner" of the bottom window.

I should update this answer so it's a bit more general.

In the above example, I've dragged the corner of the Properties pane up to make the Outliner pane go away but I don't see any trivial (single step) way to make the Properties pane go away so that I'm left with just the 3d View and (in my case) the Timeline pane below it. I was able to get what I want by dragging down the 3d View to make the Timeline pane go away and then dragging it right to make the Properties pane go away, then I added back the Timeline pane below it. (I have a 2nd monitor so the things I "got rid of" are on it.)

@lumpynose Shift + Space is a quick shortcut to get only the 3d view. If you get rid of the outliner the properties pane should now align with the 3d view so you should be able to join those.

This doesn't work, the handle cannot be dragged down. This answer is wrong or unclearly phrased.

What don't you understand about it or what's not working for you? Does another answer on this post have a better explanation? Share a picture / gif is possible @TomášZato

This must have been the first UI ever created and then no one else followed its conventions. Sorry, I'm just trying to account for its backasswardness.

An alternative to iKlsR's answer:
You can close a panel by right clicking on the line between the two pannels (i.e. the shadowed area. Your mouse will turn into a double-sided arrow when you hover) and clicking join area:

Also known as the pre-2.5 method. Which I use, cause I'm old and i never figured out the corners stuff. I set up screen sets and use them for ages anyway.


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Turntable rotation with Y-axis up add-on
Blender is hardwired to work with the Z-axis pointing upward, which is pretty inconvenient if one wants to import the game engine's physic simulation to a third party framework which happens to have the Y-axis pointing upwards.
While the vertices data can be exported to most 3d modeling formats swapping two axis with no problem, the game physics exporter doesn't allow to swap the axis.
One solution is to rotate the view to place the Y-axis up, whis is my approach, but it has the inconvenient to mess the turntable mode rotation, which main axis of rotation is aligned parallel to the Z-axis.
So it would be very handy to have a turntable rotation mode with the main axis of rotation aligned parallel to the Y-axis.

Update:
Most third party game engines, would need two files to be exported, the vertices data (.obj in my case), and the physics simulation data (.bullet)
Objects can be modeled independently of the axis pointing upwards, as long as the exported data have the right axis up, there wouldn't be any problem.
The built-in physics simulation can't be exported with the axes swapped, let's say it is Y up hardwired.
Then there is the third party game engine, which happens to use OpenGL's Y-axis up convention.
So my approach is to leave the third party game engine, and the Blender's physics exporter untouched, then export the vertices data as is, without any axis swapping.
The only problem (sort of) is that it would require to use blender with Y-axis up, which at this point means to be able to navigate "naturally" with Y up.

space_view3d_turntable_y_up.py
Enable turntable rotation with Y axis up.
space_view3d_turntable_z_up.py
Enable turntable rotation with Z axis up.
space_view3d_turntable_any_up.py
Enable turntable rotation with any axis up, the axis that is the most vertically aligned is the up axis for the turntable rotation until a new mouse gesture, i.e. until either the mouse button or the keyboard key modiffier is released.

All addons have the keyboard combination by default to
Ctrl+Left Mouse Drag because there is no need to install them all.
Neither disables the built-in view rotation, so that one can have both the trackball (built-in) and the turntable (addon) at the same time mapping them to diferent keys.

We will probably get a few questions about alternate up-axis,
In general I'd suggest that importers and exports have the ability to switch axis (many bundled formats already support this - obj, fbx, x3d, ply).
Then these tools can default to using the up axis most common with the format they are dealing with.
You could make a Blender scene with an alternative up axis - but I think this would become annoying to work with since various view options assume z-up (turn-table, numpad-keys, fly-mode-roll-correction...)

Yes, probably I would have to write more add ons, it depends on the trade off, either working with two models or rotating the entire scene before exporting the physics simulation, or in the other hand, adding addons as they are needed to support more navigation options with Y up.

@rraallvv, my point is that the exporter should be able to handle the rotation. Writing addons to handle this can work to a point, but I think its not going to give a very good workflow, though perhaps it could be made good-enough :)

I agree, I've edited the question to clarify the motivation. It appears to me that changing Blenders navigation to support Y up, brings a bit more of flexibility.


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Car model does not render after using motion tracking, but its visible in viewport
I am fairly new to Blender.(I am an experienced Maya 3D artist) I'm using version 2.83 on an iMac. I have rendered simple 3D models before using blender and the Eevee engine. But I need to test motion tracking and photo realistic 3D car rendering for work. I have followed a good motion tracking and rendering tutorial on youtube, but since I have the motion tracking figured out and scaled correctly with my car model, it will not render. If I add a sphere to the scene it will not render. The only thing that shows up in my renders is the image sequence background that I used for the motion tracking. I have checked my render layers, the car is render enabled. The Cycles render engine is selected. I can see the car in the viewports, but it never renders! Can someone please help? I am attaching a screenshot.

Did you press f12 to render? Also read: https://blender.stackexchange.com/a/108876/92768

When you press "setup tracking scene" after solving the camera movement, blender creates two collections: a foreground (with a cube as reference) and a background (a plane to catch shadows).
You can safely delete the background one if you don't need a shadow catcher.
See: https://blender.stackexchange.com/a/108876/92768

Thanks for the reply, but I think I figured out the problem. It seems that I started my motion tracking project having already had a car model in my scene. When I followed the motion tracking tutorial it disabled the render abilities for the car model somehow. So I started the tutorial again with an empty scene, and then appended my car model into the scene after the tracking and camera solving. This worked! I can now render my car and its shadows.

@LemonHat all that you need to do is incorporate the collection where the car is to the rendered collections, or add a node in the compositor to have the contents of the collection where the car is so that the information can be available for compositing. No need to do things over.


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Slow motion video like TWIXTOR for vse
How could I achieve the Twixtor effect with the VSE (Twixtor in After Effects).

Hi, could you please describe what "effect" you actually want? Questions should be complete in themselves without needing to watch external videos.

I can't explain it in too much detail, it's basically a transition effect that kinda looks like slow motion but really smooth and a bit more warped, I tried my best but it's easier to see the video and without it the question is really difficult to answer

You can't.
Twixtor, and other apps that do slow motion, use a technology called Optical Flow that estimates motion vectors to create interpolation.
There is no way, that I'm aware of, to do optical flow in blender.
Blender has no temporal interpolation for video other than repeat or drop frames, or cross-fade (frame-blend) between two frames.
None of those will give you the smoothness of extreme slow motion.
For an open source alternative to do optical flow re-timing try
http://slowmovideo.granjow.net/
or
https://linuxhint.com/slowmovideo-slow-motion-video-marker/

another free alternative is Davinci Resolve free.

@brockmann you are right. Optical flow and Speed warp are for paying customers only...  still a bit cheaper than twixtor, and a much better editor than the VSE.

That's for sure @susu

Blender 2.90 has an option to use frame-blend interpolation. You'll find it in the speed strip settings:

Yeah, but the question is about optical flow right?


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Compositor: Uncontrollable glare and noise artifacts
In the compositor, I often have an uncontrollable glare I don't know how to get rid of. Usually, tweaking the threshold fixes the problem, but not with those noisy artifacts. Here is my basic setting:

And here is my artifacts:

I have noticed that the material provoking this is often (maybe always?) some kind of metal. How do you use metal and glare without have this kind of glitch?
Thanks for your time!

You're using a multiply node, which can get crazy.  Remember light values can go far above 1.

It helps if you understand how the threshold control works.  https://blender.stackexchange.com/questions/54168/any-way-to-control-light-halos-in-the-compositor-based-on-emission-level/54173#54173. As for the noise, it is hard to tell without more information. It looks like could be artifacts caused by the denoiser,or some kind of incompatibility in the GPU. Please [edit] your post and add more information and a link to your project.

I just ran into this on a file I was setting up involving some sparklers outputting very intense light to also illuminate the scene they were in.
It's something the scene denoiser was causing in combination with the glare node. I specifically was using the default scene denoiser of NLM, haven't played around with other denoisers to see if one is less susceptible to this.
If I sourced the "noisy image" socket and then used the compositor's denoising node after the glare (with the appropriate data passes output and hooked up), it fixed the problem.
Hope that helps, especially if anyone else runs into the same thing and stumbles across this article like I did.

Well, I spent this morning investigating (another time) this issue and finally found out!
To make glass more interesting I need base color > 1, with some color. I know this is not physically correct, but it looks nice. However it also produces this artifact.
A lot of time wasted on this... but now I know. Thanks Allen and susu for your input!


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Slow edit when using subdivision modifier
When i create a Suzanne monkey in a new file
i put subdiv modifier at 3 and try to grab a vertex, it's slow a bit.
But when subdivided by 4 in the modifier it's very slow. The viewport is slow in rotation and moving even slower in 5 the subdivision modifirer.
My machine can't work with more than 30 thousands verts without slowing down
All of that just in edit mode, completely unusable.
I tried windows 10 and 8.1 with different drivers and tried blender 2.8 and 2.79 all has the same problem.

Dude, breathe! Try to use punctuation.marks and make use of paragraphs when asking questions.

"my machine can't work with more than 30 thousands verts without slowing down" that is not correct given the written above (if I understood it correctly of course). If you add 5 levels of subdivision you're dealing with half of million polygons or 1mln tris which is computed each time you move something in Edit mode. That's resources-hungry task though it should run quickly with more or less decent cpu

Your machine slowing down is completely normal, since that isn't a very new processor, and when it has to deal with a subdivision modifier with a value of 5, it would be surprising if it didn't slow down. I have a much beefier CPU, and my computer still slows down with that many subdivisions.

Sorry for my bad English, i am not native

I was making a model of big gun but when i subdivided it to 2 it had a 30 thousands verts and it was slow, i am not over using of subdiv modifier....... And it that true i think it should not slow down at that while a much weaker laptop of my friends don't slow with the same file of the gun With subdiv 3

You could also use the viewport to just preview the model without moving and then make it 2 again, that works quite well. I do it with a Pentium N4200 and 4GB Ram, and a built-in Intel Graphics 505 without good cooling and it works well. I do have lower poly models tho.

Why do you need 5 subdivision levels while you are editing an object?
With each level, your geometry is getting subdivided, creating more vertices: out of every quad at least 4 virtual quads will be created per level of subdivision. A single quad, subdivided to level 5, will result in 1089 vertices, 2112 edges and 1024 faces.
Blender will of course be slow when you have that many vertices, but you shouldn't need that big of a subdivision surface. First of all, if the object has Shade Smooth on, you probably won't even see a difference between 4 and 5 subdivision levels.
Also, you will notice that there is both a View and a Render number of subdivisions:

So, as in the image above, I have only 2 subdivision levels while I am working one the model, so it is fast, but when I render the image with my model, it changes to be 5 subdivision levels so it looks good but isn't slow while I am working.
So, the solution is that you don't need to make your machine faster, you can just use less subdivision levels while working.

I was making a model of big gun but when i subdivided it to 2 it had a 30 thousands verts and it was slow, i am not over using of subdiv modifier....... And it that true i think it should not slow down at that while a much weaker laptop of my friends don't slow with the same file of the gun With subdiv 3


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How to achieve a retroreflector material in Blender Internal
As the title says how can I achieve a retroreflector (like you would see on bikes and street signs) material in Blender Internal? I haven't been able to figure it out, is something impossible to do in Blender?
I'd like to pull off something like this:

Or this:

It is possible.
Retroreflectors reflect the light back in the direction it came from without regard of their surface normal.
In principle you can do it like this with a node material:

The material only uses Specular light and the surface normals are overwritten wih the View Vector of the active camera. This ensures that a specular reflection is only seen when the light comes from the direction of the View Vector.
The Multiply node is optional. It can be used in combination with the compositor to simulate the glow you can see in the photos.
I used these Specular properties:

These are the test results from this material setup:
Same direction of light and camera:

Light has a bit different direction:

Light outside reflective angle:

Of course real retroreflective materials have some ambient reflections too. For brevity I left them out. It is easy to add some ambient components in the node material.


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How do I get lit textured materials in Multitexture BGE?
As the title says, how can I get Materials that contain textures to work and not be shadeless in BGE that is set to Multitexture mode? I cannot use GLSL.
I need to use materials so I can control the specularity of my objects. If I set the Blend mode for my textures to Mix the object becomes shadeless, if I set it to multiply the object becomes black.
Here are some pics to demonstrate my predicament...
Normal viewport:

BGE running, texture set to mix:

BGE running, texture set to multiply:

BGE running, no material assigned (using UV image texture):

It seems you are in 'Shaded able

Unwrap the UV texture
Add a material
Check "Face Textures" under Options in the materials panel.

You may now adjust the spec.  Make sure the textures panel is empty.

I could have searched my whole life before knowing the texture stack has to be empty....Thanks. Also is it possible to use normal maps in Multitexture mode ?


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How to transfer a shape key between different meshes?
As the title says how would I go about transferring a shape key between two different meshes? The meshes I am using have a similar shape and topology (esp. with area that is affected by the shape key) but different vertex count.
I am aware of the "Transfer Shape Key" function but that requires a mesh with an exact number of vertices and I don't think simply matching the vertex count will work out right (like random verts flying off to oblivion when using that shape key).

This explains matching geometry


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How to get Blender Internal-like specularity in Cycles?
As the title says how can I achieve the kind of specularity you see in Blender Internal like Phong, CookTorr, etc. in Cycles. I've gotten close with a diffuse and glossy shader put together with an add shader but no dice.
Is there a certain Cycles node layout that can achieve the kind of specularity (again like phong and etc.) like in Blender Internal? Also we can't use different scenes it must be in one scene and rendered only with cycles.

The best way i found is to create an additional light source which affects only to glossy. http://youtu.be/fvt01QRMbng

The new Principled BSDF shader found in Blender 2.79+ can give similar looking specularity seen in the Blender Internal Renderer.

A specular highlight in real life is in fact a reflection of a light source, so to get a physically accurate highlight, the glossy shader is what you want.
However, another way to get such a highlight is the Toon shader:

This shader gives you more control over the exact size and smoothness of the highlight.

Does the Toon shader mimic a traditional specular highlight model like Phong?

@Justin no, it can't be, because Cycles is physically based and behaves differently. The bigger the 'specular' is, the dimmer it gets for example. Traditional specular highlight ignores this. There are other differences too.

I think I may have gotten the specularity down. What I did was use the diffuse and glossy shader with the add shader. Next I added a MixRGB node that's set to multiply with white (or whatever color you want) and pure black and connected the color output to the glossy node. The factor for the MixRGB node controls the intensity of glossy node (and thus the specularity).
Here's a pic that demonstrates the effect:

I'm not sure if there are any caveats to this trick but it does give me an effect similar to Blender Internal's specularity.
EDIT: This method is physically incorrect, the glossy shader will end up brightening the scene, esp. if the glossy color is set too bright. Should only really be used for special cases.

This answer is wrong and leads to incorrect results - leaving this comment here for anyone stumbling upon this and not knowing how nodes work. Pls feel free to disregard the "Best answer" check-mark.

Yeah, using the add shader like that will result in physically inaccurate results. I was using add method because mixing was giving me ugly, unsatisfactory looking results. Fortunately the newfangled Principled BSDF shader in 2.79+ is giving me satisfactory specularity.

You could use the Glossy BSDF  and a plane that emits light (Emission set to 2.9, Sun at default).

With roughness set to 0 the shape of the plane is recognizable:

Setting the roughness to .1 a highlight similiar to phong will be rendered.

You're on the right track, and @stacker 's answer is good, but using a Mix Shader to mix glossy and diffuse shaders will give you the best of both worlds. You can control the blurriness of the reflections with the roughness on the glossy shader, and you can control how bright the highlights are by mixing in more or less diffuse (using the factor value on the mix shader).
It's still not quite the same as phong/blinn/lambert/cook-torr but it'll get close.