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What version of blender approves 441000hz for audio
Im experiencing issues with blender. When i startup the 2.79 version, a black box opens with the Cannot use 441000hz, use 48000hz, so i changed my audio settings and all. Yet, it still doesn't seem to work. im in dire need of using blender for a project im doing. My laptop is an lenovo Ideapad 320. Please help

I don't thi k it's the sound frequency that is meant by that.

whats the problem then? cos its impossible for me to figure out

I would like to know too. I know I had this issue too. I did something that fixed it but I'm sorry, I really cannot remember

What doesn't work?

blender itself. when i start it up, it shows a console black box saying that i cannot use 41000hz and must use 48000hz, which i adjusted but didn't fix anything.

Ok, let me guess... are you trying to use the Steam version of Blender?

Hey, look! I found you on Steam. See my answer to your question there.


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How can I make this Dodecahedron shaped product?
I'm trying to recreate this product for a client in Blender.

I really thought it would be a simple project, but I cannot figure it out!
I'm including the blend file here if it helps:

Here's how I got to this point.

I didn't see an easy way to create the Dodecahedron shape so I started with a circle and changed the number of vertices to 5.  I fill that shape in, duplicated it and tried my best to recreate the shape, merging vertices as I went.  I then used the Cast modifier to straighten out my shape and then at each vertices, I created an ico sphere.
I did try a regular sphere and also a sub-d cube, but after those attempts failed I tried an ico sphere.  I then attempted to delete the faces where the bars would connect each sphere, and would try bridge loops to connect the two spheres together.  But the angles I could never get right.  I've also tried mirror modifiers, but it's actually kind of a difficult shape that's hard to mirror and get right.
I then thought I could use the wireframe modifier on the shape and use a boolean modifer to merge with the ico spheres, it just didn't work, or at least isn't professional enough for this project.
I need to make this look as close to the product as possible, including the seams.
Any help is greatly appreciated!
Thank you!

The shipped add-on: Add Mesh: Extra Objects  gives you Math Function > Regular Solids > Dodecahedron :D

https://blend-exchange.giantcowfilms.com

https://blender.stackexchange.com/questions/28789

@DuarteFarrajotaRamos This addon looks very interesting and maybe just what I needed but I've just finished the model without it.  If it's not good enough, I'll try using this.  Thank you!

@DuarteFarrajotaRamos The blend exchange is exactly what I was looking for.  Didn't want to keep using my onedrive.  Thanks for the link!

As @Robin Betts said, Use the addon Add Mesh: Extra Objects to create the Dodecahedron.

Then in edit mode select the rouge edges that you can't use and dissolve them.

The select everything and delete only faces.
Back in object mode and convert to curve.
Now it is a curve object you can easily add roundness to the segments by increasing the bevel size, this is nice because you can come back later to change the size if you need to.

Now it's a simple matter of adding your favorite sphere shape and snapping its centre to every vertex of the dodecahedron. I recommend using ALT-D to duplicate so that if you want to change their size you can do them all at the same time.

For the seams, you could add a plane along where it needs to be, then use the knife tool to cut it up with some randomness and give it some slight thickness with a Solidify modifier and maybe a subsurf if it needs it.

Thank you for your answer.  This really helped me get the shape down, the only tricky part for me was making it look connected between the sphere and the cylinders and using the boolean union was difficult to make it look right.  However, I think it might be close enough.  I didn't understand your method about the seams, however, you're little trick to convert the mesh into a curve and changing the depth of the bevel worked really well to create the seams.  I just selected an edge from the mesh and converted that to a curve.  It turned out quit nice!  Thank you for your help!

source: Stack Exchange

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

sort: votes


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Fill grid with instances for puzzles
Is there a way to fill grid with instances like on picture. Different colors are different plane instances.

Does the green rectangle correspond to 4 instances?

Yes, they are the same but scale is different.

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


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Render cutting off
I've re-started (3.0) and I've never had this problem before, the render will not show the full 1920x1080 image that I'm expecting to see. There appears to be small orange "crop" marks at the corner of this image but its cutting it off?

Ssounds as if you've inadvertantly selected a render region with CTRL-B. Try CTRL-ALT-B and see if you see the full image.

Look at the status bar and you can see it's doing tiled rendering just with two very large tiles.  Once that segment of your image finishes it will move on to the other.

provide blend file so we can check it out instead of guessing...

As we can see in the informations above your render, it is mentioned that you are rendering tiles.
Tile rendering is most likely not preferable to use since v3.0. So unless you have a specific setup that you know requires it, I suggest you turn it off.
Properties Editor > Render tab > Performance panel > Memory subpanel > uncheck Use Tiling:

L0Lock......awesome! Thank you so much. I was going insane trying to figure this out and I have no idea how that checkbox got selected/ticked. Cheers!

AFAIK it is checked by default, but the default tile size is 2048, which is big enough to fill a 1920x1080 render at once. If you have an addon that impacts that or opened a .blend from a previous Blender version, that could be why.

This file was opened from 2.9 and I wanted to render it (for Client) using 3.0 so perhaps that helps to explain as you suggest.

Absolutely! Cycles got a big rewrite for v3.0, so previous versions of Blender had a very different way of handling render and particularly the tiles system is very different. (In a way, Blender doesn't use one render device per tile anymore, so the previous principle of "divide and conquer" we used to have isn't valid as of 3.0. But Any scene created with an older version still used tiles settings that are made around that old principle. So be aware of that.


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Need help sculping wand! Using brushes seemed to be stretched horizontally
Here is the blender project file: Download Here
My daughter really wants this particular Harry Potter Wand she saw from some Pottermore website.  It's basically some quiz she took that finds the right wand for her.  I tried to search online to purchase one like it but couldn't find a 12 1/2 inch Unicorn Hair Core wand.  LOL.  So being new to blender, and thinking it would be a fun first project, I'd try to sculpt it from an image and get a 3D print of it.
I was actually off to a really good start and have the basic shape of the wand down almost perfectly, but when I try to start sculpting and adding details, the brushes all seem to be stretched horizontally.
This is how I started.  I imported the image of the wand and created a cylinder to match its length. I then used Ctrl+R to create the different sections, scaled them and moved them to match the wand's shape.  This was all done under the Modeling tab.  I press Ctrl+5 as I've seen in some tutorials before you start sculping to smooth it and applied the subdivisions.
I head over to the Sculpting tab and with any brush, I use it's all distorted and stretched.  I should also note that some of the brushes are move very slowly. I need to make it faster somehow, as my computer starts to freeze up a little.  I have an i7 processor and a GTX 660, I think it should be fast enough to handle this, other graphics programs work just fine, so maybe there's a setting somewhere to make it flow better?
Please see the photos and maybe my issue will make more sense.  Any help is greatly appreciated.  Also, I should note, I've only been using Blender for 3 weeks, I think I'm doing pretty good, just need a little help.
Thank you!!

I think it's better to upload your project using blend-exchange so someone can take a look at it. https://blend-exchange.giantcowfilms.com/

If I understand correctly with Ctrl+5 in Object mode you added Subsurf modifier (you can check that in Modifiers tab) and then started sculpting. Sculpt should be done with Multires modifier instead as it's supporting all the tools of Sculpt mode. Stretched result of brushes means either unapplied scale of the object (Object mode > Ctrl+A) or uneven loopcuts on the mesh surface. Sculpt is acting as expected when topology consists of relatively same sized tris or quads so make sure to check mesh topology before sculpting

@Abel - Thank you!  I've added the download to my post.

@MrZak - Thanks for the reply.  I'll research this and see if it helps.  Under the Modifiers tab it says "Subdivision" but I applied it before sculpt.  Not sure if that makes a difference.

@MrZak - Using the Multires modifier seems to be more responsive, but I can't seem to edit any of the settings for it.  Also, the brushes are still stretched.... so maybe this is more to do with uneven loopcuts?  That part is new to me.  I'm thinking these are when I added the cuts using Ctrl+R?  Still experimenting to figure it out.  Any other tips are appreciated.  Thank you much!

Without looking at the file - this is most likely a duplicate of this: https://blender.stackexchange.com/questions/120697/what-is-this-anomaly-when-im-trying-to-sculpt-and-how-do-i-fix-it

@MrZak It took some time to figure out, but Ctrl+A > Scale in object mode fixed the issue and once I enabled the Dyntopo I got the look I was looking for.  Thank you, everyone, for your help!

This is a common mistake on newer users.
you have to apply the  scale of the object.
to do so press "Ctrl A" and then apply scale
If you look at the side bar you can see
"Location"
"Rotation"
"Scale"
"Dimensions"
The difference between scale and dimensions is that dimensions is in real world values such as cm, m, inch, foot... While the scale is the stretching of the object.
If you press "S" in object mode you will scale using the scale values and distort the object. It can be useful sometimes but usually you should apply the scale.


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can`t remove selected face
I was trying to remove selected face.
So I entered edit mode and selected designated faces

pressed delete (face) and got below result

I don`t know why vertexes and edges still exist
How to remove this completely?

I have uploaded my project file.it is from the C-130 model made by manilov.ap in https://skfb.ly/6OR7z. (CC BY 4.0)

do I missed something?

Try to select the vértices of the circle and delet them

after face delete? no I can`t select any edges or vertices in edit mode(in edges, vertices mode)

probably because you had a duplicate of the wire frame. Try to first remove doubles.

@IgorSvara removed doubles but nothing is changed...

please share your file: https://blend-exchange.giantcowfilms.com/

@moonboots it is from https://skfb.ly/6OR7z I was trying to customize this model

ok but please share the part with the problem so that we can check

@moonboots have added project file sir

there are several windows, you should tell which one you tried, it looks like it works, maybe you've chosen X > Faces Only instead of X > Faces?

so I just checked the model and didn't have any problem deleting every single window, so be sure to select the part of the mesh you want to delete and press delete face not face only. Also, select all the mesh with A and merge by distance, because on the model you shared there are 600 double vertices.

@moonboots I uploaded gif and I have selected Faces not only Faces only. and was trying to remove all windows

@IgorSvara did I missed something? I have uploaded gif which contains whole process

These are different objects.

You can edit them all together by selecting them and switching to edit mode.

By the way, Blender has .WRL importer:

but it seems to be broken for the recent versions.

Generally it is better to download original files from SketchFab because glTF messes them up.


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How to get reference clip to start in middle of timeline?
Cycles Render Vers- 2.79
I need to use a reference clip for the final action of my animation, but that action starts at frame 720, and the reference clip ends at frame 300. How do i get the reference clip to start at a desired key frame on the timeline?
Thank you.

If I understand the question, you've got a set of animation keyframes for the model in the dopesheet already at frame 1?  If so is there any reason you can't simply slide them as a whole, up to frame 720?

I dont know if that would solve my issue, if im understanding you. I would have to figure out how to get my reference animation to start at frame 1440, then. The reference clip  and animations would start at frame 720 instead of frame 1.

Er - frame 1440? Like 720 x 2?

Tell me, is the ref clip in the Action Editor or NLA by any chance?

Im sorry im still very new at this. What is NLA?
The reference clip is in the background images

I know how you feel! (lol)  Are the keyframes actually in the Dopesheet and at frame 1?

Oh yes, the keyframes are in the dope sheet and at frame 1. I need the reference clip im using in background images to start at frame 720.

I see there are highlited keyframes and non-highlited.  Are the highlited ones the ref clip you want to move?

hmmmm... i dont know, to be honest. Give me a second to mess with stuff and find out, thank you.

Dang... No the unhighlighted key frames were not the clip. Just unhighlighted.

Basically, all that's needed (fingers crossed) is to press 'A' to clear the highlites, then  'B'  (for box select) and drag the box to ONLY include the keyframes you want.  Once the mouse button is released, Press key G (for grab) and move the mouse without buttons pressed to the right.  The highlited keyframes will move also.  Take the leftmost keyframe(s) up to the frame number you wish to start at.

A useful hint - at the bottom of the Dopesheet, you'll see a ghost icon, click on that and the arrow icon next to it to declutter the DopeSheet.  Only the object(s) selected will appear in the Dopesheet.

Does the reference clip located in the background images show up in the dope sheet? I thought the dope sheet shows animation key frames? i dont need to move the animation i already have made, i need to start the externally sourced reference clip located in the background images at frame 720. the only keyframes in the dope sheet i can find are movements i made to the model and not the reference clip im using to make the animation.

Apologies - I was seeing the ref clip as animation clips.  For an image that's a lot easier.  I'm using vers 2.77a here so 2.79 might be a little different.  Here goes - Go to the texture properties for your background plane and open the image tab. Down at the bottom of that section are boxes that - hang on a sec...

...to continue - a box called "Auto refresh"  Tick that to make the anim move.  At the left of that is another pair - "start & offset."   The "START" slot is the frame number you want the clip to start from in Blender's timeline.  The Offset moves the starting frame IN the CLIP itself to somewhere after the beginning of the clip.  Sorry for the confusion. You showed all those keyframes and I took it to mean you needed to shift those.  (I call keyframes ref clips that can be imported into other projects)

ohhh i see. Sorry about the confusion. I should have used the term "movie clip" as thats how its titled in blender.
Thank you so much

Your welcome - have you tried it yet?

I am working on finding everything. Maybe .77 is a little more different than .79. Im trying to find the texture properties for the background plane.

Not a problem.  I'll head off for a bite to eat (Australian time) and look in in a half hour...  If anyone's watching and familiar with 2.79 we could use some help. :)   BTW you have to select your model, then at the extreme right are the properties panels.   You click on the Material tab first, then the texture, a coloured checkerboard of sorts.

Back again - After no less than 20 comments/exchanges, I think an answer post would be in order if only to clearly set out the process.  I'll place one up now and if it's not the answer for you, drop another comment at the answer itself and I'll delete it.  Happy Blending...

Texturing a plane with a video/image- For a Background Image see Edit below...
I'm using vers 2.77a here so 2.79 might be a little different. Here goes -
Select your model first in the 3D window.
At the extreme right are the 'Properties panels'.  The one with a small brown sphere is the "Material properties panel"  Click on that.
Go to the Texture properties next.  That's shown as a tiny coloured checkerboard of
sorts.  Click on that.
Go down to the "Image" tab and open that.
Down near the bottom is a tick-box called "Auto Refresh".  Make sure that's ticked to
make the video play.
At the left of that is a pair of slots - "Start & Offset".
Click in the "Start slot and enter the Blender timeline frame-number that you want the video to commence playing from.
The Offset slot points to the frame number within the video-clip itself that it's to treat as it's first frame.  (like pulling a tape or film strip through a player and starting from there)

EDIT 27th April 2019 - re Movie clip as a Background Image -
The same applies in the bkd image's panel.
Press N to open up the Viewport's properties. Scroll down to the "Background Image" tab and open that.  Click on the image folder icon to open your movie.
In there you'll see the same tick-boxes and entry slots as mentioned above.
You'll notice the "Opacity" slider is set at half by default.  Wind it up to 100% for full opacity.

Thank you. I was able to finish my animation, thanks to your help.

That's good news.  In the interim and away from the computer it dawned on me that you were using a background image, not texturing a plane as I guessed when looking at your pics. (appearing to be subdivided planes and actors texturing those.  Fortunately the same tick boxes would be in the Bkd Image panel so I guess you would have found those ok.  You got there, that's the main thing.  I was wondering, do you think we should delete all 'dem comments above?  They'd sure make a good comedy script!  lol  Exercise in communication!

Thanks @Leander, you're quick!  I can see that in your link, trying to figure out how to bring it up.  Will go back into Edit mode and see what I can find. -- Back again but cannot see anything re 'Side by side'.

@Leander , Found what you referring to.  I'm a little puzzled. The two texts need a divider line for sure.  I'll read up a Stack Exchange link I saved yonks ago, re formatting. Can't see anything like that in the shortcuts at the top of the edit box.

Sorted it out @Leander.  My eyes are nowhere near what they used to be and I use the Windows' black screen with yellow text, high contrast so I can read what's there.  Your edit even with side by side didn't show.  I've added a ruler line but it's so faint when viewed with the normal Windows setup, it's all but invisible, to my peepers at least.   A short divider as I've been using draws attention to the division and doesn't go right across so it doesn't appear to be a separate answer.  So, I can't use that style anymore?

I just though you didn't know about the thin line divider. I can see it fine in different setups. If you think it is too faint, use whatever divider you want.

Thanks @Leander.  The quarter line is visible in all setups and emphasizes the division.  This is often necessary to direct a reader's attention to the (sub)division and separate the context of what's between them and the main body that surrounds it.  Thanks for your interest though.


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No sound from sequencer in certain scene
I have a blend with two scenes, and the same audio strip is in both sequence editors. One scene has sound and the other one doesn’t, even though both strips are unmuted and have volume at 1. I vaguely remember having done this on purpose a long time ago (with this file), but I don’t remember where. Any thoughts on things to check?
The blend file, on OneDrive.

In the Playback settings of the Sequencer you have enabled Mute in the scene without sound.

Thank you, and God bless!


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Looking for a “Convex hull” like algorithm, 2D at a time, for modeling clothes
I am trying to put realistic clothes on characters created with MB lab, and I have decided that if I could have a version of the convex hull algorithm that worked on two dimensions at a time instead of all three, it would create decent clothes that wouldn’t look like the character was in shrinkwrap. Does anyone know of such an algorithm that exists?
What I mean is probably best explained by going through the mesh along one or two axes (probably Z and Y), cross sections at a time, and creating a convex hull for the results of each cross-section.

Does it have to be Blender?  https://doc.cgal.org/latest/Convex_hull_2/index.html

Well, this is the Blender Stackexchange but I guess not. Will try to check out, though I prefer Blender strongly: it’s what I know.


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Using quick smoke cannot change from smoke to fire
When I use quick effects -> quick smoke to create my domain and stuff for me, I have had trouble if I made a mistake as to wether I wanted smoke or fire, and then tried to change it later. Once it is created, there seems to be no way to visually change it from smoke to fire. Even if I get all the physics working right for fire, all that renders is the small amount of smoke emitted by the flames. Setting up the solid viewport color for flames demonstrates the physics side is working because the flames do fade upward like they should.
How can I make a quick effect smoke domain have fire in it after it has already been initiated for smoke?

Good question. I once noticed the same exactly issue, and could never figure out what the problem was. This feature worked as expected in 2.79, and seems not to have worked ever since.

Probably the material cause this problem. Try to append it from a working blend file.

The material set up is one principled volume node in either case, but I will go ahead and try.

I think I might have it! I redid the effect, and I see that in the material, black body intensity is turned all the way up. I’m pretty sure it was zero before…

After changing the emitter type from smoke to fire, in the domain material’s principled volume node, turn the black body intensity value all the way up to one.


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How to make Named Attribute affect Volume material, and not just Surface?
I am trying to hack together a way to make glowing neon brighter near the center of a tube. My current GN setup generates a layered tube from an input curve (unbeveled, spline only), and sets a named attribute called "neon_glow" from 0 at the outermost layer to the number of layers minus 1 for the innermost (so, an integer range).
Node tree (in two pieces so the text is ledgible):

In case you can’t tell from the tightly packed wires, the named attribute is applied to each layer of the geometry after it has been converted to mesh with a radius, and since even volumetric materials are also only assigned to a surface, I figured that would be enough.
With the attribute fed to the shader's Surface output directly, it looks as expected:

But when the attribute gets multiplied and fed to an Emission shader's Strength input, which is then fed to the Volume output of the shader, I see nothing:

I am using the Cycles render engine.
Why is this, and is there a workaround?

Just seeing the incomplete Geometry Nodes setup makes it guess work, but first of all I assume the object has no inner geometry/points? The values are stored on points, so only the surface of the object contains attribute data - there are no values inside the volume. For the reason why there is absolutely nothing to see we maybe need even more information, like what values are stored there, how did you get them and also which render engine are you using? Best would be to upload the file so that we do not have to rebuild everything (especially the part we do not see in the screenshot).

I’m sorry, I was on StackExchange late last night and I didn’t do a very good job at anything. Will upload my file when I get a chance. No, the curve doesn’t start off with any internal geometry, it’s just a spline.

For “what values are stored there,” I did say that it was “from 0 at the outermost layer to the number of layers minus 1 for the innermost.” They are all integers.

Attributes to shading through Instances
The issue
You can't read geometry (mesh) attributes to use for volume shading. The issue is, your attribute has a different value on each point of its domain. How do you choose how interpolate this attribute for a volume ? Non-trivial question, and currently impossible. On top of that, attributes aren't implemented yet for volume : https://projects.blender.org/blender/blender/pulls/115270.
Here are 3 edge-cases when trying to pass mesh attributes to volume. These are the two cylinders, with some vertices highlighted and some arbitrary values representing the attribute. Note that orange is on the mesh domain, where blue is on the volume domain.

Issue 1 : Point between two meshes. This is the least complicated issue, you could just ask Blender to choose the cylinder we are inside. But still, 0.5 seems to be the logical choice if equal distance to 0 and 1.
Issue 2 : Point inside both meshes. How do you choose which cylinder gives the attribute ? Technically this point is inside both meshes.
Issue 3 : Point at equal distance to multiple values. How do you choose which value to use ? What about the surrounding values, do you take them into account ? Is this like a gradient where neighbours affect the attributes ? How do you compute the distances for this part, euclidean distance, taxicab distance, something else ?

As you can see the current implementation of attributes doesn't manage this kind of case.
Solution with instances
I found a solution that works if you are okay with your cylinders being Instances.
By forcing your cylinders to be Instances, you can read the instance attribute in shading. This is only one value per instance, which you can use for volumes. As I see it, it bypass the issue of interpolating the attribute values, it's just one value as any other value of your shading nodes.
Here is the geometry nodes :

And then in shading editor, just use your attribute on the instance domain :

"How do you choose how interpolate this attribute for a volume?" Each layer of the cylinder is expected to be filled with a constant volume. I was not expecting to be able to interpolate between them. I added further details to the question body.

What about the volume that is inside both cylinders ? And how do you interpolate corners (euler distance VS taxicab) ? Yes you set the attribute to one value per mesh, but that doesn't change the fact that you have one value per vertex, and Blender needs to interpolate that. So really not possible with how attributes works for now.

"And how do you interpolate corners (euler distance VS taxicab)?" I do not understand this, but for a brief moment I DID understand why an attribute being different throughout layered cylinders with the same material would need interpolation of some kind, so I know you're correct. I'll try to apply the instance system to my full node setup, sorry it was late.

I'll update with a sketch to explain the issue.


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Simulating neon: Find angle between two vectors with shader nodes
I am attempting to simulate neon inside a glass tube (a real neon light and not those florescent ones), and am having difficulty making the innermost portion of gas look brighter than the outermost portion. This is real neon. You can see that near the sides of the tube, the light is dimmer. That is not an illusion caused by glare, although the glare amplifies it. I have seen it up close, though, and inside the tube it does fade toward the edge.

…and this is what I have (yes it’s too dim, but I want it on low power for now). The neon is just plain Jane emission volumetric, and it of course does not fade near the side of the tube like real neon does: the edge is hard, as if I stuffed the tube with glowing paint instead of gas. There is a bit of fading, but that’s done with compositing via glare, and isn’t realistic enough for me.

The structure of this is two identical curves, both beveled, one larger than the other, and that larger one has a solidify modifier on it: A properly walled glass pipe is around a solid tube of neon, with some margin in between (that vacuum margin is not there in real life, but the neon probably won’t glow there anyway).
I have decided that if I can compare the incoming camera ray to the normal of the neon "gas" tube (not the glass), I can use that to control the emission strength: The greater the difference/angle between them, the dimmer the neon should be. This may not work on the flipside of the neon as the ray exits...
This solution probably comes down to a dot product, but there may be other solutions. Leave your suggestions in the comments! :-)

Hi :). Could you please add an image to illustrate the problem and your current node setup? For those of us with bad imagination. Thanks :).

@JachymMichal I don’t think you have a bad imagination, but I will add screenshots and such.

Cheers for that ;)

@JachymMichal I tried to clarify, but the neon sign I saw in real life was in the daytime, and of course not many people on the Internet photograph neon in the daytime.

I think the angle you want is given by arccos( (a \dot b) / (||a|| ||b||) ), based on solving the geometric defn of the dot product (https://en.wikipedia.org/wiki/Dot_product#Geometric_definition) for the angle between the two vectors?

Try using a Fresnel node and skip the math?

@NeverConvex I’m not entirely sure what you just said, but I’ll look into if the other guy’s idea doesn’t work. Thx

@RonJensen yes! I knew I had done it before somehow. That will probably give me what I need. :-)

A Fresnel node does seem simpler and likely to work, but just to clarify, @TheLabCat: in the expression I wrote, a would be the camera vector, b the normal vector, arccos is the inverse of the usual cosine function (math node has an arccos implementation, I think), || || is the Euclidean norm (or just Length in shader node terms, I believe) and so you could in principle just plug together a few nodes to compute this angle. May need to multiply the camera or normal vectors by -1, depending on how you're imagining the geometry's orientation, but that was the idea behind the math

Much the same method as yours.. A geometry-bevelled curve for the glass, with a Solidify modifier to make it a tube. A duplicate of the curve, with a smaller bevel, for the gas.
The glass is just a standard, colourless,  almost 0-Roughness, almost 1-Transmission principled BSDF.
The gas uses a the 'Facing' output of a Layer Weight node to make the mask shown on the left, below,  to mix between a Transparent and Emission shaders as shown on the right.

..but it still takes a fair bit of tweaking to make it feel 'gaseous'..

Although I think the Fresnel and Layer Weight solutions are probably the natural way to achieve this in Blender, I thought @TheLabCat's original intuition was interesting enough to want to try to produce directly in shader nodes:

I have decided that if I can compare the incoming camera ray to the normal of the neon "gas" tube (not the glass), I can use that to control the emission strength: The greater the difference/angle between them, the dimmer the neon should be. This may not work on the flipside of the neon as the ray exits...

First, here's an example of how this turned out in my quick test:

And, second, here's the primary node system for computing the inner tube's shading, based on direct calculation of the angle between the incoming camera ray and the normal as arccos( [c \dot n] / [ ||c|| ||n|| ] ), where c is the camera ray, n the normal, arccos the usual inverse of the usual trigonometric cos function, and || || is the Euclidean norm (corresponding to Blender's Length operation in Vector Math nodes):

The Frame labels explain what each of the major operations here is doing. The arccos expression used is just the result of solving the "geometric definition" (which is the equation a \dot b = ||a|| ||b|| cos(theta), for theta the angle formed between the vectors a, b) of the usual vector dot product for the angle between the two vectors. The definition can be found on wikipedia, for example, here, as of the time of this answer: https://en.wikipedia.org/wiki/Dot_product#Geometric_definition
Maybe I should also add that the Map Range in the right-most Frame is used to convert from the range of arccos (which is [0, pi], in Blender's implementation) to [0,1] (which is more useful for using as a mix factor), and that the Vector Transform from Camera to World coordinates in the left-most Frame is really, really important (took me about thirty minutes to realize not having it is was why nothing was making sense visually!).
I'll note that I didn't put any real effort into the outer tube's "glass" material; I've just used a mix of a Glass BSDF and Transparent BSDF here. Improving it might improve the result. Also, neither of these cylinders is beveled; I concentrated on just the materials.

Nice. +1. I do wonder though, whether the expensive arccos is worth it, since the result goes through a fairly arbitrary Color Ramp anyway, and the whole remapping from dot-product could be done in there? Maybe I'm missing something..

I think that's a good point; arccos is only really needed if you want to think in rads or in degrees. It also ensures you know the range of inputs to pass into the Map Range node, but I think (c \dot n) / (||c|| ||n||) should already live in [-1,1], so you could probably optimize it a bit by deleting the middle Frame and entirely and connecting the first Frame output directly to the Color Ramp, like you're saying, I think

Also.. the View Vector is in Camera space, where the Geometry > Normal is in World space, so you would expect the effect to be view-dependent..

Yeah, definitely view-dependent; the View Vector is converted into World space so it isn't expressed in the basis used in Camera space, but the effect will still vary as the view is moved around, of course. I think that's a property it shares with Fresnel (just from playing around with the Fresnel node a bit in Blender), and with Facing too (the 'light' regions seem to turn towards me as I rotate around a target object)? If imposing the effect from a fixed angle were desired, it would be easy enough to replace the View Vector with some user-specified vector of choice, though

Ahhh.. so sorry, missed your conversion! (I've just slapped my own wrist.)  For both of us, since the object is to keep the illusion of a brightness in the middle of a volume, it's lucky that neon tubes are cylindrical :D

A Fresnel node like this maybe:

I am not sure the index of refraction is quite right, but it’s a good starting point for me :-) thank you.

As I look at it more an emission shader might be better than a principled bsdf for the gas

This is the solution I’m working with for now. In the future, I may just use two volumetric tubes, but I’m not sure.


text:
Problem with ProRender making things transparent (2.82a)
I installed the AMD's ProRender render engine for Blender, but all the renders using the GPU come off as a faulty render.
I updated my drivers, restarted the PC, and run a test on my hardware, and everything was fine. My hardware is an AMD FX8350 and a R9 270.
This is how the images look when rendering
Render with only CPU

Render with CPU + GPU

Any help with the problem would be apreciated
Edit: Here's a gif if it helps


text:
Scale and Rotate Stopped Working
I am using Blender 2.80 beta. In Object Mode Scaling and Rotating objects stopped working.
How do I enable rotating and scaling again?
The button that is referenced in Blender 2.7x does not exist in Blender 2.80.
The odd thing is if I create a new model everything works fine...it just stopped working on my original model and still isnt working.
???

Possible duplicate of How come I can't rotate?

In the latest release the tool options header is hidden by default. However, the same options can be accessed from the Property panel.
From the panel, go to the Active Tool and Workspace settings tab > Options header > Transform > Affect Only and then uncheck all (Origins; Locations; Parents).

If you can't scale/ rotate in Blender 2.8a you can solve this problem by clicking on the right top header "Options" field and unchecking all

Probably you have activated the Only Origins option. You can find it in the end of pivot point menu.


text:
Armature object disappears when rendering
Everything is visible in the render viewport, but when I render the image my model disappears. I saw that this can happen when an armature is parented to it, but I dont know how to fix it. Feels like Ive tried everything.
Heres the blend file.
https://www.dropbox.com/s/mj9044td6viq7z6/RoyalSkiesLLC-RoyalRig-Female2.9.blend1?dl=0
Thank you in advanced!

please show us what you have (viewport) and your rendered result as screenshots. Thank you.

Don't know how to solve (I think it's a bug), but I can tell you that the problem is not about rendering, it's about animation: The mesh gets rendered, but in a weird loc and deformation. I think this is due to a wrong evaluation of its path constraint, which is ok in viewport, but it's not ok in render. I've found this problem before, in constraints and modifiers applied to Grease Pencil objects. To pratically solve you should try to get rid of that path constraint, or use the simple viewport render. Hope it helps.

Thank you guys for the advice, for some reason I just moved the rigged model into a collection unrelated to the armature and it seemed to have worked. No idea why. I appreciate the support!!


text:
How to animate UV mask position in Blender Render?
I'm trying to create an animation of a rising sun. I know it's easier to just make a whole object moving, but for a specific reasons I can't take this approach.
What I'm trying to achieve is to change UV mask Y position in time using keyframes. So I tried pressing i  button with mouse hovering a proper value, but what I get is a warning:
Button doesn't appear to have any property information attached (ptr.data = 000000000000, prop = 00000000000)
I think this printscreen might be a better explaination:

You can't keyframe the UV island's location, but you can add keyframes to node parameters. Try the "Mapping" node in the node editor. https://docs.blender.org/manual/en/2.79/render/cycles/nodes/types/vector/mapping.html

@FFeller, you can animate the islands location with the addon that's included with blender, called the AnimAll addon.

Thanks, I will check it out.

After a little more research and thanks to @FFeller comment to my question I figured out that animating UV island's location is not possible. Besides of using a mapping node, I've found a simpler solution.
When all you need is animating UV island's location, you can animate UV Map offset instead. The property can be found in texture tab of the texture that should be animated.

actually, like I replied to FFeller, you can animate the uv island position. :)

Thats not an island, it's the whole UV.

Summarizing, You have minimum three ways to transform UM map:

"Mapping" node in the node editor.
"Mapping" texture.
Use UVProject or UVWarp modifiers.


text:
How can I make a ponytail?
I am trying to make a ponytail, particularly one that is fastened high up on the back of the head. I want it to look realistic, but attempting to animate a "hairbob" sliding over it and moving into position has only worked until it was getting close to the right size, when half the hair popped through it. Is there any particular way to fix this besides jacking up the basic particle settings? Some kind of hair particle constraint?
Edit: This is what I want it to be shaped like, though I want movable hair. I would prefer something that looks realistic (why do women in space wear shiny leotards?):

Please add a reference image of what you want to get.

@susu Sigh. I’m still stuck on this, and I like that style a lot.

Does this help you? https://blender.stackexchange.com/questions/209220/how-do-i-distribute-hair-particles-evenly-using-guiding-curves-ponytail-with-h

That looks like exactly what I need! I may want to mark this question as a duplicate…


text:
HowTo make fish fins without hard-modeling (IE: one vertex at a time making RAT mesh)
I am wanting to make a sea serpent, and he needs a top fin. Thing is I am stumped as to how to make such a fin without doing about 30 RAT (right about there) operations, let alone produce geometrically "nice" results with realistic looking curves. I am perceiving a Subdivision Surface modifier, but is there a quicker way to create the base mesh?
I want something with obvious spines, and pulled down, thinner membranes between them. In real life this would look so much like a cloth draped over posts in a row I've considered doing that, but is there another way?
This is the serpent with SS modifier on it, the fin prototype as a separate object in edit mode. The main trouble here has been making skin between the spines but also making the spines end up thicker.

hello, what have you tried? where are you now, currently in the process? What reference images are you working with that could be added to the question via [edit]? Please add more information to narrow the question scope, and clarity. Thanks

A few things with "Skin" modifier. Maybe I'm just being lazy... 2) I have a "digiplastic" grey worm with little strings of vertices coming out of his back, barely resembling a fin in my opinion. 3) The drawing I made 3 days before I started the model :D

I feel like I've been getting not as good at asking questions. Help me, God.

Please add new information in the body of your question, there are many users that do not read comments, and it helps keep the site more organized if all information is contained the same way. Plus comments are not searchable by search engines, so their information is not very useful over time...

Again. Please add a reference image, or sketch of what you want to get. Also what do you mean by RAT?

RAT means "Right about there."

@RBlong2us and what is that supposed to mean?

I believe it's editing vertex by vertex to get a certain look.

Correct. In origami, it means basically making irreproduceable results. In blender, technically any result is reproduceable, but in this case I mean doing one vertex at a time, because the tools cannot do it, in turn because there is no guideline or main logic to use. RAT folds are because of the same reason, although the process logic admittedly works slightly different.

I've got something, though a bit tedious, that worked :D
Did not screenshoot the process, but it's fairly straightforward.

Make each membrane area into a face (necessarily creating an edge between the tips of the spines.

Wireframe the resulting mesh, deleting the original (can use modifier, but must apply after setting up).

Delete all top and bottom bars of the resulted wireframe (meaning deleting horizontal edges, basically). What is left will be spines with edge-only ends.

Create edges and faces as needed to manifold-ize the spines.

For every pair of spines (1-2, 2-3, 3-4, etc):
-- Select the faces on the sides of the two spines that face eachother.
-- Use "Inset Faces" to create the area where the membrane will join onto the spine.
-- Switch to vertex selection mode, and select less.
-- Delete the selected vertices. The area for membrane joining is now open.
-- Select both spines entirely, and then "Select Boundary Loop." The ring around the membrane joining place should be selected.
-- "Bridge Edge Loops," bumping up the number of cuts to that of a low-poly mesh, setting the Interpolation to "Linear," and the profile shape to "Sphere," turning down the profile factor to create the pulled in effect. The pair of spines are now connected and re-manifold-ed.
-- Select "Boundary Loop" again and "Mark Sharp" for shading purposes.

Continue for each spine pair.

Select the bottom of the mesh, and scale it along the Z axis to zero. Potentially make additional adjustments to the membrane, working to make it smooth, between any spines that did not have the same number of vertices as the ones they are connected to.

Mark the edges surrounding the bottom as sharp.

Shade the mesh as smooth.

Add a subdivision surface modifier to the mesh.

Use vertex painting to mark the spines as white, and the membranes as black.

Use that vertex coloring to control the shaders as neccesary.

PTL :)


text:
Geometry Nodes: Normals incorrect on extruded curve. How to fix/workaround?
I have this railing (mounted on some posts, with a floor, and a tree trunk not relevant)
, generated with these nodes:
As you can see, the outer half of the railing is getting its normals flipped the wrong way. How should I avoid this flipping?

your specific solution:

you can flip faces like this:

This worked! Thank you. I will accept the answer in 6 minutes LW.

you are welcome

How about this: first scale the radius to the inner ring, and extrude from that value to the outer ring.

I had considered that, but I would rather avoid it because of the extra maths amongst the nodes.

extra math, but less vertices ;-)

(Arc Radius + Rail Width / 2) / Arc Radius = Scale of the inner Ring, and then extrude from there.

Maybe I should do that, though. Would still have to flip the normals of the original curve so it looks right, but maybe this might help later on. I guess it depends on which requires more computing power: the extra nodes, or the extra vertices.

As you can see, you not only have a clean mesh here, but also one less extrude mesh node. In sum, this is less computational overhead.


text:
How to make instances twist about a curve
I am wanting this ring to appear as a twisted chain, hopefully with a variable number of 180 turns it makes as an integer input to the Geometry Nodes group. I want the chain to be twisted as a whole. I.e. if you were to cut the loop and suspend the chain so it hung from an end, it would untwist, like a twisted rope swing.
This is the ring I have with the geometry notes. This is currently incorrect:

These are the nodes I have:

How best to make instances twist about a curve in Geometry Nodes?
Edit: Here is a demo of what I'd like to achieve. Apologies that the rings are intersecting each other. This is not desired: They are meant to realistically link together.

Note that I would like to be able to adjust the starting angle, to achieve a rolling effect, like this:

can u pls show a picture how it should look like?

do you mean like this? [1]: https://i.sstatic.net/npoGM.png

@Chris I have added a demo of what I would like it to look like.

last try....do you want this? [1]: https://i.sstatic.net/Y70SJ.gif

@Chris Not quite. You got the rolling effect, but I also want the chain to be twisted as a whole. I.e., if you were to cut this loop and let the chain hang straight from an end, it would untwist.

Do you mean something like this?

Each link's points are rotated about its local Y by a function of its local X, before being instanced on a circle, and then converted to a mesh.

... which can be animated by key-framing the tilt angle of the Set Tilt node in the Main Ring cluster:

You can introduce an initial twist to the chain, of, say, pi * the main ring's (0-1) Spline Parameter, and animate a delta: an additional angle to that....

.. with this sort of 'rolling' result:

Not quite, but thank you for pointing out the curve to points node as a source of some orientation. I bet that’ll help in the final solution.

You’ve got the roll, but I also want the chain to be twisted as a whole. I.e. if you were to cut it and hang it vertically, it would untwist like a twisted rope swing. I have clarified in the original question.

@TheLabCat 3rd time lucky? :)

YES! PTL that’s it.


text:
How to get same hair particles from collection in second particle system/ or how to delete instanced particles without converting them to real meshes?
I made a relatively huge landscape which has rocks scattered on it with a particle (hair) system. Then as I wanted to simulate some objects falling down a mountain I wanted to give the scattered stones (particles) also an rigidbody(passive) so the falling objects would collide more reallisticly with them and not only pass through them.
The problem is that the landscape is to big and the scattered rocks are to countless for efficiently running a rigidbody simulation. Therefore I simplified the landscape (unsubdivided) as a second mesh and used only the necessary part (boolean after particles in modifier stack) as a passive rigidbody.
I couldn’t delete the original faces because that would change the distribution of particles in relation of the collider-mesh to the rendering-mesh.
I discovered the particle-edit-mode which first appeared as the solution. The new problem here is with particle systems in general, that if you instance from collection, and give the second mesh (collider-mesh) a single user particle system, the seeds are different even if “pick random” is unchecked. That means I cant get the same rocks at the same position.

Deleted Particles in Partice-Edit-Mode to reduce the particles to the area needed for rigidbody-simulation:

Seeds are diffrent in single-user particle systems:

Has anyone an idea to fix that problem with the particle system or knows an alternative workflow that would accomplish my goal? Even on a reduced scale, the small rocks are to countless to do anything by hand or convert them to real meshes (facecount would rise in the 10-100 millions).
A question that came up with one possible solution is found here:   How to get instanced object from particle system at location?

Found a makeshift solution via Python: Get transform of Instances and the corresponding instanced mesh and create a new mesh in a separate collection with the transform and mesh data of the instance.
Converting all Particles to a real mesh wouldn’t be possible because of face-count but creating new meshes for only those particles in the area of the rb simulation is doable.
import bpy

context = bpy.context

dg = context.evaluated_depsgraph_get()

    # objects that are spawned from particle system via collection as source
obj_cube = bpy.data.objects['Cube']
obj_colum = bpy.data.objects['Colum']
obj_ico = bpy.data.objects['Icosphere']
    # empty collection to spawn the new meshes to
new_collection = bpy.data.collections['SecondInstances']

counter = 0
for i in dg.object_instances:
    obj = i.object
    print(obj.name)
        #filter all objects that are not instances by is_instence
    if not i.is_instance:
        print("not an instance")
    else:
        print(f"Instance of {obj.name} at {i.matrix_world}")
        counter += 1

        if obj.name == 'Cube':
                #create new object and keep data (also modifiers) from right source object
            new_obj = obj_cube.copy()
            new_obj.data = obj_cube.data.copy()
            new_obj.animation_data_clear()
                #set new_object transform from instance transform
            new_obj.matrix_world = i.matrix_world
                #move to seperate collection
            new_collection.objects.link(new_obj)

        elif obj.name == 'Colum':
            new_obj = obj_colum.copy()
            new_obj.data = obj_colum.data.copy()
            new_obj.animation_data_clear()
            new_obj.matrix_world = i.matrix_world
            new_collection.objects.link(new_obj)

        elif obj.name == 'Icosphere':
            new_obj = obj_ico.copy()
            new_obj.data = obj_ico.data.copy()
            new_obj.animation_data_clear()
            new_obj.matrix_world = i.matrix_world
            new_collection.objects.link(new_obj)

I will keep the question open for now, because maybe there is a better way and having real meshes is not ideal either and could be optimized?


text:
Animation Nodes Flow Controll?
In comparrison with Unreal Blueprints i felt the need of Flow Controll in Animation Nodes, like gate. Is there another way then routing - for example - the transformation to an empty like in my example?
To compare Blueprints and AN is a bit off but i need the functionality to work with huge numbers of categorised objects. expl.: all chairs to height 1, all shelfes to height 2.

Can you elaborate on what you are trying to do? We are not all familiar with UE4 blueprints.

It works as in the example, but i dont like it aesthetically, so I though maby there is a better way I don’t know about. Im still learning AN.

Specifically I want nodes/node-branches only to be activated under certain conditions. Expl.: there is a list 500 objects with 3 categories: chair, desk, bed. They have random sizes, but I already have a list in wich category they are in (0 = chair, 1 = desk, 2 = bed). Now I want to scale all chairs to z-height 1, all desks to z-height 1,5 and all beds to z-height 0,5.

At the moment in my example all branches are executed but when the category-list entry doesn’t match the case-function then the transformation is applied to the empty and not the object. This works but I would like to only activate necessary branches and not all.

Please don't add answers as edits. You may add an answer to your own question and accept it after couple of days if you wish to.

Given the list of objects, their classes (0, 1, 2), and sizes of each class. We can evaluate the sizes list at the classes list and use the output as the scale as follows:

Omar Ahmad's answer is good for my specific problem and i learned something from it, thx! But i found another solution with a simple pythonscript to shorten the nodetree from the first example and solve the aesthetic problem, because the empty was redundant in the first place. now the functionality is more like a switch/case as in coding and not binary anymore.


text:
Own AddOn Python: poll function by type kills AddOn-undo-menue because of former type conversion
My AddOn converts the selected curve to a mesh. With the poll def() I want to grey out the AddOn-button for other object types then curves. the problem is that the undo-menue that should apear in the bottom left after execution with all the props vanishes/doesnt show up because of this, because the object type isnt curve anymore, i think.
excerpt poll:
@classmethod
        def poll(cls, context):
            return context.object.select_get() and context.object.type == 'CURVE'

excerpt undo-menue-activation:
bl_options = {'REGISTER', 'UNDO'}

For better comprehension of the problem here the full script:
(its used for a very specific svg to mesh for 3d-printing workflow. It works only on imported and selected svg-object)
bl_info = {
    "name": "SVG_Center&Extrude",
    "author": "AM",
    "version": (1, 0),
    "blender": (2, 80, 0),
    "location": "View3D > Object",
    "description": "specific workflow for svg to extruded printable form",
    "warning": "",
    "wiki_url": "",
    "category": "Object",
}

import bpy
from bpy.types import(
    AddonPreferences,
    Operator,
    Panel,
    PropertyGroup,
)
from bpy.props import(FloatVectorProperty)
from bpy.props import(FloatProperty)

class OBJECT_OT_SVG_CnE(Operator):
    bl_label = "[SVG] CnE"
    bl_idname = "object.svg_cne"
    bl_description = "specific workflow for svg to extruded printable form"
    bl_space_type = "VIEW_3D"
    bl_region_type = "UI"
    bl_options = {'REGISTER', 'UNDO'}

    height = bpy.props.FloatProperty(
        name = "Extrude Height",
        default = 1,
        description = "height",
    )

    scale: bpy.props.FloatProperty(
        name = "XY Scale",
        default = 100.0,
        description = "Scale",
    )

    resolution = bpy.props.FloatProperty(
        name = "Preview Resolution",
        default = 12,
        description = "Preview Resolution",
    )

    #@classmethod
    #def poll(cls, context):
    #    return context.object.select_get() and context.object.type in ['CURVE']

    def invoke(self, context, event):
        return context.window_manager.invoke_props_dialog(self)

    def execute(self, context):
        #   prerequisites:
        #   1: import SVG-File
        #   2: select imported object!
        #   3: run this script

        #check if curve
        if context.object.type != 'CURVE':
            return {'CANCELLED'}

        extrudeHeight = 0.0, 0.0, self.height
        scale = self.scale, self.scale, self.scale

        bpy.ops.object.origin_set(type='ORIGIN_GEOMETRY', center='MEDIAN')

        bpy.context.object.location[1] = 0

        bpy.context.object.location[2] = 0

        bpy.context.object.location[0] = 0

        bpy.ops.transform.resize(value=scale, orient_type='GLOBAL', orient_matrix=((1, 0, 0), (0, 1, 0), (0, 0, 1)), orient_matrix_type='GLOBAL', mirror=True, use_proportional_edit=False, proportional_edit_falloff='SMOOTH', proportional_size=1, use_proportional_connected=False, use_proportional_projected=False)

        bpy.ops.object.transform_apply(location=False, rotation=False, scale=True)

        bpy.context.object.data.fill_mode = 'NONE'

        bpy.context.object.data.resolution_u = self.resolution

        bpy.ops.object.convert(target='MESH')

        bpy.ops.object.editmode_toggle()

        bpy.ops.mesh.select_all(action='SELECT')

        bpy.ops.mesh.edge_face_add()

        bpy.ops.mesh.extrude_region_move(MESH_OT_extrude_region={"use_normal_flip":False, "mirror":False}, TRANSFORM_OT_translate={"value":extrudeHeight, "orient_type":'NORMAL', "orient_matrix":((-0.163277, -0.98658, 0), (0.98658, -0.163277, 0), (0, 0, 1)), "orient_matrix_type":'NORMAL', "constraint_axis":(False, False, True), "mirror":False, "use_proportional_edit":False, "proportional_edit_falloff":'SMOOTH', "proportional_size":1, "use_proportional_connected":False, "use_proportional_projected":False, "snap":False, "snap_target":'CLOSEST', "snap_point":(0, 0, 0), "snap_align":False, "snap_normal":(0, 0, 0), "gpencil_strokes":False, "cursor_transform":False, "texture_space":False, "remove_on_cancel":False, "release_confirm":False, "use_accurate":False})

        bpy.ops.object.editmode_toggle()

        bpy.context.object.active_material.diffuse_color = (1, 1, 1, 1)
        return {'FINISHED'}

def menu_func(self, context):
    self.layout.operator(OBJECT_OT_SVG_CnE.bl_idname)

def register():
    bpy.utils.register_class(OBJECT_OT_SVG_CnE)
    bpy.types.VIEW3D_MT_object.append(menu_func)

def unregister():
    bpy.utils.unregister_class(OBJECT_OT_SVG_CnE)
    bpy.types.VIEW3D_MT_object.remove(menu_func)

if __name__ == "__main__":
    register()

Possible thoughts in witch direction a solution could work, without the knowledge how to do it:

check if mesh was a curve type one step before (don’t know if that’s possible and reliable with the undo menue)

store that the object has been converted with the execute function in the last step and therefore make an exception in the poll function to return true. (don’t know how to do that, because im not shure how the poll def with @classmethod works executionwise, because its “async-like” every  tick, so im not shure how to give it a boolean variable for example)

give the object itself some kind of variable – expl. custom property - of being converted that one could check with bpy.context.object etc. (but has to be deleted/changed after further steps)

Maybe the divide between a bpy.ops.curve... and a bpy.ops.mesh... operator is too "big". Consider making it two operators.

Have you tried experimenting with bpy.ops.ed.undo_push ?  It's says internal only but others have used successfully

@batFINGER sry i dont understand, do you mean in the poll function return?

@Merlin thx for the tipp! were would you put that, cant find any ressource how to use bpy.ops.ed.undo_push()

https://blenderartists.org/t/best-practice-for-allowing-undo-to-work-in-custom-operators/1137780


text:
When rendering, Cycles and Eevee only renders some materials
I was following along with a tutorial and finally finished my first model, when I try to render however it only renders some of the materials.
The render I get.

Screenshot of the materials that go missing.

Sword.blend1

hello, could you please tell what material are you talking about? Also, if it has to do with an image texture maybe pack the images into the file before sharing (File > External Data > Pack All Into .blend)

I’m not sure the materials go missing. Are you talking about what look like reflections of the surroundings on the sword? I have repeatedly thought something was wrong with my metallic materials when that happened in material preview but disappeared in render, but it turns out that’s just because the world background in the material preview is automatically an HDR texture, and in cycles or EEVEE render it defaults to flat gray which makes no reflections.
Just change the World background to something interesting (an environment texture from blender’s own data files works great) and metallic materials should look much better .
As for the glow effect, this is likely because you enabled bloom while using EEVEE, but then switched to cycles render. The bloom will still appear in material preview. You can create a bloom like effect for cycles using the glare node in the compositor .

Thanks! This worked wonderfully


text:
Bad Topology problem
Hope you and your families are ok in that moments, and i hope de will pass that soon.
I have a topology problem, the result is a problem on subdision.
I have that object, when i apply the subsdivision surface, the circle goes to a "non circle".
I don't know where i have to cut the mesh to break the loop that distorts that circle.
Thank you.

Thank you very much batFINGER and Robin Betts,
in fact tihs is the vest topology lesseon i have never recieved, that let me understand better the workflow for a good topology.
I have one more question, dou you know why the external part is not beieng correctly subdivided?

Moltes gràcies!

The bigger up / down hole has an "outset" ring around the hole, would add similar.

Agreed. The distortion is caused by uneven sizes in the immediately surrounding faces, Catmull-Clark is pulling further into the larger faces.

I would do something like this. But depends what you want to do next

Thank you very much Fowl, batFINGER and Robin Betts,
in fact tihs is the vest topology lesseon i have never recieved, that let me understand better the workflow for a good topology.
I have one more question, dou you know why the external part is not beieng correctly subdivided?

isnt that just not-smoothed? right click on the object and ->shade smooth.


text:
Has Anyone Ever Tried Modelling a Battery Cover?
I recently inherited my late great grandmother's Sharp WQ-CD120 boombox from 1995.
Everything appears to be fine except it's missing the battery cover. I can't find anyone selling them online so I thought I'd model one in Blender myself to 3D print.
Here's what I've come up with so far:

I know for the top 2 extruding parts that I'll need to be like the part of other battery covers that have that dip in the middle. As for the bottom 4 smaller extruding parts, I think they'll need some sort of hook on the ends.
How do I go about doing this?
Also, I tried looking for tutorials online to no avail. I saw some about modelling batteries, but not battery covers.

Please show your current work.  You may also see video tutorials on the website which has the name that rhymes with NooNube.  You might consider including a reference image, more specifics, and showing more effort in your question.  It is interesting how your question might be closed soon without explanation.  Perhaps its due to all the effort in whining and wailing occuring on meta. Its spreading like a virus ☀.

Sarcastic edits to the question don't help giving good answers. It does quite the opposite, I dare to say. Overall your topic is still very specific, regarding the fact that Blender is a 3D modelling tool with quite a big variety of uses, which means that the part of the community who uses it for 3D printing is quite small compared to the people who use Blender for e.g. animation. Maybe Blender StackExchange just the wrong platform for the right question?

It seems like your asking for some help adding the 3d parts of this model.

I know for the top 2 extruding parts that I'll need to be like the part of other battery covers that have that dip in the middle. As for the bottom 4 smaller extruding parts, I think they'll need some sort of hook on the ends.

This can be done many ways. You may already be familiar with some of them. The most effective would probably be edit mode in blender. You should look into "proportional editing" and "boolean modifiers".
I would model the tabs as a 2d face side profile and extrude them. You could then use an array and boolean modifier to make the final mesh.


text:
Why i have White Texture?
I am trying to make this sphere using two different textures following a tutorial online

However when I try to add the second texture it becomes white

You add values of the second texture on top of the first texture. Color values become nearer to 1 which is white. So it's quite expected behaviour. I would suggest not to add image textures on top of each other at all, adding is often done on masks used for mixing textures.

It is unclear what you are trying to achieve. Please edit the question and explain it in more detail.

you see the first picture ? i am trying to make that sphere, its made of 2 textures of bricks ok ?  when i add the first texture to the sphere it's fine(it's clear and red),now when i add the second layer (with different brick texture) instead of giving me the original color of the texture it give me White Version of it

How do your textures look? What do you wish adding the second texture to the first one to do?


text:
How to make old nostalgic looking sky in blender?
I want to make an old nostalgic looking sky that represents the 90s or 80s or even the early 2000s,
you know the exactly like images from an old photo album,
I want to make something like this

"Nostalgic looking sky that represents the 90s or 80s" The sky hasn't really changed appearance much throughout time. Looks like you either want a low resolution image, or some sort of color or image filter to emulate old film or low dynamic range.

Just do a sky with less pollution than today and you are set.

Do you already have an image of clouds, or do you need to make the texture? What I mean is, are you looking to make the cloud texture. the "old-school" effect, or both?

i want to add both :)


text:
Polygons shifted after random clicking
I was following Blender Guru's tutorial when I accidentally went into layout mode. I didn't realise this and clicked a load of random things and this happened:

Can it be fixed or do I need to start again?

Crtl+Z... ?

maybe you've enabled the snap option?

Hello and welcome. Please use a descriptive title that reflects the content of your question

Just move the vertices back where you want them in Edit mode. Looks like they’ve been moved only in the X direction so should be simple enough to G (grab), X (in X axis only), drag them back. There aren’t many so shouldn’t take long to put them back.
It’s difficult to give more precise instructions without knowing about what it is you did to mess them up.


text:
Scale toilet paper cylinder witout affecting inner hole in preparation for unity
I am trying to make a toilet paper like object in blender.
I have cut a hole in cylinder with boolean modifier. The problem is when I scale this object in Unity the hole gets bigger as we expect. I need to set this object so that I can scale only the outside of the cylinder. Can I restrict which parts should be scaled? Even when this is possible I don't know whether Unity will do the same thing. I'm new in Blender. Thanks for help!

On a second look i'd say it can be a blender question, if edited a bit. Because unity has none such mesh editing functions as needed in this case and blender can function as a preparetion for unity. answer is coming soon :)

Unity has only simple transform tools that cant handle this case. Blender can be used to prepare the object for this.
ShapeKeys are the way to go:

Setup your object either totally "full" or "empty"
Create a basis and a key (in Object Data properties)
Select key and edit/scale your mesh with Shift + X to full/empty in Edit Mode.
Export to unity as FBX.
Import BlendShapes should be active by default
In the Skinned Mesh Render > BlendShapes play with your keys

Important: the collider of your base object is static, transformations with BlendShapes have no affect on the collider.

Thank you so so so much!!!! Finally I have achieved what I want. I was thinking so much how I could get this done but had no idea about these blendshapes. Thanks again! :))


text:
Objects with Simulation, How to merge them into one?
I have a number of objects in a simulation. I'd like to merge them into a single object on the fly, so I can apply modifiers to the collective.
Currently I'm using an Empty with a Boolean modifier which brings together the simulated objects, but I don't want it to perform the actual Boolean operation, just merge all the individual objects into a single one so Modifiers can be applied.
This will keep the simulation live whilst allowing for some useful post simulation modifier changes.
I hope that explains what I'm after. So basically I want to use a Modifier on an Empty that brings all objects in a Collection together into a single object, like Boolean, but without the Boolean operation taking place. Thanks

The native integration of Geometry Nodes is capable of copying mesh data of single objects or a collection of objects to a target object.
(Updated from @Chris Marshalls suggestion)

Alternatively you can try the AddOn Animation Nodes with the Mesh Object Input and Output node. This works also with multiple Input meshes to one target. But Geometry Nodes should be faster.

Thanks for this. rather than using the add-on, Geometry Nodes in the latest blender does the job too. So thanks for helping!

Good to know, glad it helped! Didnt go into Geometry nodes quite yet ;)

I have edited the answer accordingly to your suggestion. Please consider it as correct if so. Best regards!

So the answer above mentions the Animation Nodes plugin, but in the latest Blender, Geometry Nodes does the same thing. I don't know about the history of Blender nodes, but it looks like the plugin has been wrapped into Blender now.
The answer works by creating a base object, eg a cube, add a Geometry Node Modifier. In the Geometry Nodes window plug an Add>Input>Collection Info node into the Group Output node. So now the all the geometry from the Collection objects gets merged on the fly. The cube geometry is over ridden so is lost.
So this answers my question.


text:
How to ease the edges of a volumetric texture?
I have a volumetric texture, and I don't know how I can ease the edges of this texture, to rub the "cube shape" of the volumetric texture.
I also need this to be keyframed.

I tried to use different combinations of gradient texture nodes, transparency node too, but I was not able to rub the edges.
Can you help me ?
Here's the node setup:

Here's a blend file :
Bye guys ! :)

Hello :). Not an answer, but you could use a sphere instead of a cube. Then the edges will be softer.

Using another Shape is indeed not a bad idea. (@Jachym Michal)
But here is a node setup to give you pretty good controll of the density border.
For better visibility I haven't multiplied it with your current density setup yet, but the math node already is sitting in place as you can see.

Sweet, learned something new here, thanks :).


text:
How to animate an image sequence texture?
I'm trying to create an animated texture, in this case a lava flowing look on a static mesh.
The 'lava' only consist of 10 frames atm, the texture animation would be looped.
However I have come across several problems.

the textures doesn't update/animate when the i press play?
how to keyframe this? can't seem to keyframe the nodes?
it's suppose to loop when I tick the cyclic option? Doesn't seem to loop.

here is a screenshot of the settings i used on the image node.

You need to indicate the number of frames you want to be used for the sequence:

From the documentation here:

Frames
Sets the range of frames to use.


text:
Boolean modifier not working for simple objects
I am trying to make a floor plan which I can 3D print.
I started by using a base cuboid, and then added rooms of specific dimensions with the hope of using the Boolean difference to remove the volume from the base cuboid.
Please see attached .blend.
When I use the Boolean modifier, it seems to have trouble showing me the end result (the faces look like they are ripping, tearing or just look weird??) and when I try to look at the item in Cura, it doesn't seem to have shown the Boolean difference modifier working.
I have tried using 'remove doubles' and 'limited dissolve' but no luck.
Any help would be great please.
Note: I have tried using the bevel modifier after the booleans and no luck; also tried applying the modifiers and it still comes out being all ripped/torn.

always bevel after you booleans! (in general)
it often mitigates topology issues associated with boolean modifiers.
you could simply put a bevel modifier after the booleans, and increase the segments to 2 or 3 and set it to "angle" and see if that helps.

I have tried using bevel and applying the modifiers (and deleting the objects used for difference) but still is not working. Please help!


text:
Boolean modifier difference not engraving correctly
I am trying to make some custom chess pieces.
I am just trying to engrave some images onto the chess piece but when I use the boolean difference modifier, the piece goes crazy and doesn't really engrave it properly.
It seems to cut out faces weirdly and I also have to align the pieces up a certain way, or it won't even apply the modifier at all.
I am trying to figure out how to attach the blend file, but I can't find the button.
Any help with this would be great please!! Complete blender newbie here :(

Thanks,think I finally got the upload working now :)

The appropriate method will depend a bit on what your final use of the model will be (to make images, to 3D print...) .. so perhaps you could edit your question to include that?

You have some problems because you need to clean up a bit your meshes:

Select your symbol object, go in Edit mode, select all and W > Remove Doubles.
Also press X > Limited Dissolve.
Select your cylinder, go in Edit mode, select all and W > Remove Doubles.
Give your cylinder a Boolean modifier, choose Operation > Difference, and select your symbol as Object.
It works (well, it will need a bit of topology work)

I should really get over my Boolean allergy :D

I've learnt how to appreciate it   ;)

you should check the amazing Speedflow addon, unfortunately it's not free but it makes hardsurface works really fun.

Thx for reminding me ..  I haven't tried it yet, your recommendation gives me more confidence.. by the look of it, Lepiller deserves every penny. I wouldn't have thought that adds up to much per hour..


text:
Hear timing reference audio from VSE while editing other scenes? (2.8 beta)
I'm making an animation using grease pencil, based on a narration track. What I'd like to do:

Import and place the master audio file (narration) as a single sound
strip in the VSE, in Scene0
Create visuals as grease pencil scenes sequenced in the VSE too, from which a final export can be made. Scene1 - Scene50.
I want to use the narration track in the VSE in Scene0 as a timing reference for all visuals in all scenes of the project. e.g. in Scene3 I want a specific action to coincide with a particular word in the narration. In general while working on the action in Scene N I want to hear the relevant part of the narration audio which has been placed in the VSE in Scene0, a different scene.

I have a good handle on 1 and 2, but I'm not sure how to realise 3. Is it possible?
Suggestions for workarounds or alternative approaches are welcome too. Though I'd like to avoid any workaround that involves having to re-render audio files if the duration of any of the grease pencil scenes has to change.
EDIT
In After effects there's a plugin called 'universal audio' that achieves something similar to what I'm looking for in Blender: It provides some buttons that allow you to designate a 'master audio' track, and then from child comps automatically copy in the appropriate section of audio from the master audio track, with in point correctly reflecting its position with regard to how the two comps are related. https://aescripts.com/universal-audio/
EDIT 2
I think that if I make sure I use the Scene name 'Master' for the one containing the VSE and name the narration sound clip 'Narration', then I'd need something like the following script (i'd run this somehow each time I opened one of the scenes to work on). But I'm not clear yet on how to have this accessible via a button or something convenient.
# Run this from a 'child' scene to add narration track with correct timing offset.
# TODO add routine for removing narration track from child scene if it already exists, before re-adding it.

    import bpy

    current_scene = bpy.context.scene
    current_se = current_scene.sequence_editor_create()

    master_se = bpy.data.scenes['Master'].sequence_editor
    narration_sequence = master_se.sequences['Narration']

    timing_ref_sequence = master_se.sequences[current_scene.name]

    if timing_ref_sequence:
      offset = timing_ref_sequence.frame_final_start * -1
      path = narration_sequence.sound.filepath
      current_se.sequences.new_sound('new',path,0,offset)

Thanks, I've reworded parts of the question and added emphasis. I hope that helps make it clearer.

Lets say master audio is in scene "MasterAudio" a master audio strip added to all other scenes with drivers on props from original would do the trick?  Be an easy enough script.  Coincidentally playing around with integrating audacity ... blendaucity

@batFINGER If i'm understanding correctly a script like that would be a big help. Are you thinking that the 'MasterAudio' scene would have a VSE in which all other scenes were placed, and the script would use the start positions of the scenes in the VSE to automatically add and adjust the start position of the audio strip in those 'child' scenes?

I commend your efforts and time invested in your research. I have modified the python script, which you have started. @ alert me in a comment, if some parts of the code are unclear.

To have the python script conveniently accessible, we have to embed it into an addon for 2.8.
To activate the addon for this file only, copy the code (at the end of the post) and save it in a file (e.g. adjustNarratorTrack.py). Open it in the script editor in Blender and check the Register checkbox in the header of the script editor. With register enabled, a saved file will be automatically executed once the blend file is loaded, even if you close the script editor.
To run the script, without reloading the blend file, click RunScript.
The script creates a python operator. The operator can be called by

opening the search menu in the 3D View F3 and typing Adjust Narrator
clicking on the menu item, which we created under 3D View ▶ Object ▶ Adjust Narrator Track

Note, that this "addon" is not quite complete yet. Further research should be done as to how scene/sound strips behave, when they are cut off in the sequencer.
In the script

a custom Operator AdjustNarratorTrackOperator is defined. This will be called by Blender when you click on the menu items. It will be also available to python through bpy.ops..
two annotations of the operator are defined: audio_strip_name, cut_scene_name. These are adjustable after the operator has been executed. This is useful if you have changed your naming conventions.

The operator annotations appear in the 3D View after the operator has been executed.
there are two methods:

execute: called by Blender
adjust_audio_reference: a modified version of your script

In adjust_audio_reference the current_scene, audio_strip_name and cut_scene_name are referenced from the operators context.
Various checks are done to ensure, that

the "Master" scene exists
the "Master" scene contains the audio track
the current scene is not the "Master" scene
the current scene is contained as a strip in the "Master" scene
the sound strip is replicated in the current scene if necessary
the offset in timing is applied

In this case we want to use the frame_start property and not the frame_start_final property, since the frame offset to the frame_start_final doesn't reflect on the audio strips position at the start of a scene strip.
import bpy

class AdjustNarratorTrackOperator(bpy.types.Operator):
    """Adjusts the narrator track"""
    bl_idname = "object.adjust_narrator_track"
    bl_label = "Adjust Narrator Track"

    audio_strip_name: bpy.props.StringProperty(default='Narration')
    cut_scene_name: bpy.props.StringProperty(default='Master')

    @classmethod
    def poll(cls, context):
        return True

    def execute(self, context):
        try:
            self.adjust_audio_reference()
        except Exception as e:
            self.report({'ERROR'}, str(e))
            return {'CANCELLED'}

        return {'FINISHED'}

    def adjust_audio_reference(self):
        current_scene = bpy.context.scene
        audio_strip_name = self.audio_strip_name
        cut_scene_name = self.cut_scene_name

        # check if the master scene exists and contains the audio_strip
        master_scn = bpy.data.scenes.get(cut_scene_name)
        if master_scn == None or master_scn.sequence_editor == None:
            raise Exception('Master scene not defined.')
        master_se = master_scn.sequence_editor
        ref_audio_strip = master_se.sequences.get(audio_strip_name)
        print(ref_audio_strip)
        if ref_audio_strip == None or ref_audio_strip.type != 'SOUND':
            raise Exception('Audio strip not found.')

        # check if the current scene is embedded in the master scene
        timing_ref_seqs = [s for s in master_se.sequences if s.type == 'SCENE' and s.scene == current_scene]
        if len(timing_ref_seqs) == 0:
            raise Exception('Current scene is not contained in the Master scene.')

        ref_scn_strip = timing_ref_seqs[0]

        current_se = current_scene.sequence_editor
        if current_se == None:
            current_se = current_scene.sequence_editor_create()
        current_audio_strip = current_se.sequences.get(ref_audio_strip.name)
        if current_audio_strip != None:
            if current_audio_strip.type != 'SOUND':
                current_audio_strip.name = current_audio_strip.name + '_notSound'
                current_audio_strip = None
        if current_audio_strip == None:
            path = ref_audio_strip.sound.filepath
            current_audio_strip = current_se.sequences.new_sound(ref_audio_strip.name,path,0,0)

        timing_difference = ref_audio_strip.frame_start - ref_scn_strip.frame_start + current_scene.frame_start

        current_audio_strip.frame_start = timing_difference
        current_audio_strip.frame_final_start = timing_difference

def menu_func(self, context):
    self.layout.operator(AdjustNarratorTrackOperator.bl_idname)

def register():
    bpy.utils.register_class(AdjustNarratorTrackOperator)
    bpy.types.VIEW3D_MT_object.append(menu_func)

def unregister():
    bpy.utils.unregister_class(AdjustNarratorTrackOperator)
    bpy.types.VIEW3D_MT_object.remove(menu_func)

if __name__ == "__main__":
    register()

Thanks. Though this doesn't get at what I'm hoping for. While I'm working on Scene1 I want to be able to hear audio that I've placed in the VSE in Scene0 (Scene1 is also placed in that same VSE).

This is fantastic! Thanks very much for your time and help.

Further to my comment above this is what I had in mind
Set up a master audio scene. All it has is audio in the sequencer, no camera nothing else. For process of example I have called this scene "MasterAudio".

MasterAudio Scene
Placing this scene as a strip in any other VSE and we can hear the audio. All that is left is to align them.
The soft trim is animatable. I have added a couple of simple drivers to trim the master audio scene strip to match the context scene.  This is a bit dodgy as it doesn't seem to update that well, and has the tendency to set the scene strips frame start.

Result of running on empty scene
import bpy
context = bpy.context
master_audio_scene_name = "MasterAudio"

def add_master_audio_scene(scene):
    sed = scene.sequence_editor or scene.sequence_editor_create()
    ma_scene = bpy.data.scenes.get(master_audio_scene_name)
    mas = sed.sequences.new_scene(
            master_audio_scene_name,
            ma_scene,
            1,
            ma_scene.frame_start)
    # only use sed of mas
    mas.frame_start = scene.frame_start
    mas.frame_final_duration = scene.frame_end - scene.frame_start
    mas.use_sequence = True

    # drivers
    fcurve = mas.driver_add("frame_offset_start")
    driver = fcurve.driver
    var = driver.variables.new()
    var.name = "fs"
    #var.id_data = scene
    var.targets[0].id_type = 'SCENE'
    var.targets[0].id = scene
    var.targets[0].data_path = "frame_start"

    var = driver.variables.new()
    var.name = "mfs"
    var.targets[0].id_type = 'SCENE'
    var.targets[0].id = ma_scene
    var.targets[0].data_path = "frame_start"

    driver.expression = "max(0, fs - mfs)"
    fcurve = mas.driver_add("frame_offset_end")
    driver = fcurve.driver
    var = driver.variables.new()
    var.name = "fe"
    var.targets[0].id_type = 'SCENE'
    var.targets[0].id = scene
    var.targets[0].data_path = "frame_end"

    var = driver.variables.new()
    var.name = "mfe"
    var.targets[0].id_type = 'SCENE'
    var.targets[0].id = ma_scene
    var.targets[0].data_path = "frame_end"

    driver.expression = "max(0, mfe -fe)"

    # drivers

scene = context.scene
add_master_audio_scene(scene)

Cut your audio e.g with Audacity and , in Blender 3D view, put a Speaker object to hear your audio bit. When you go to the next frame, insert respective audio bit and so on.

This doesn't address the question.


text:
2.8. Scattered instances of animated grease pencil object, each with random time offset?
I have a grease pencil object with animation keyframes. An animation of a simple 'star' which wobbles and flickers now and then. The animation is designed to loop well.
Here's what I'd like to achieve:

Scatter many instances/copies (>100) of the GP object in my scene, without having to place each one manually. And randomly vary the scale of each instance.
Have each instance automatically face the camera at all times ('billboards').
Have each instance play back its looping animation with a random time offset, so create the illusion that these are independent objects.

So far, I've tried:
Adding a track constraint on the 'master' grease pencil object which got it to face the camera at all times. And then using a mesh as an emitter which would generate instances of the GP object as particles. This approach satisfied criteria 1 and 2, but not 3 since I found no way to add a random time offset to each particle's playback.
Any ideas very welcome!
EDIT:
I thought I'd found a way to achieve 3: by specifying start and end frame range for the particle system both below 0. But it turns out that particles' current frame always seems to match the source objects current frame. So I'm not getting the time offset variation I'm hoping for.

oh my! This is  would do an awesome tutorial! But unfortunately I´m sunk in deadlines. I want to suggest you create a time offset modifier applies to the GP (main) object. (this will act like it´s own nested timeline for your grease pencil animation timeline). Later, on the main 3D view, you´d need to create a slider parameter (this number will drive) the time offset on the grease pencil property: Time Offset. That´s the base. This is a simple setup. What you want to do on the instances now, is to drive this slider on the main 3d view with a scripted offset function using frame and timeline.

@PierreSchiller Thanks. This part loses me a bit "What you want to do on the instances now, is to drive this slider on the main 3d view with a scripted offset function using frame and timeline."

I've added an empty to my scene and set it up so that its rotation drives the time offset of the GP modifier, I hope that's approximately the direction you described going in! but I'm unclear about the next step.

@bitbutter What about duplicating your star a few times, giving each duplicate a different time offset, group them then emit the group instead of the star?


text:
Is there a way to store a workspace with a scene & auto-recall it when changing to that scene?
In my .blend file i have one scene called Master, which has a VSE containing other scenes in the file as strips.
While editing the other scenes i need to be working in a 3dview panel. While editing the Master scene i need to be in the VSE panel.
Is there a way to specify that a workspace with a big VSE panel 'belongs' with the Master scene, and a workspace with big 3d view panel belongs with all others, so that the appropriate layout is loaded when the corresponding scene is made active. I’d like to not need to manually change the workspace each time I switch between the Master scene and the others in the project.
(I don’t mind using scripting if it’s necessary, but i couldn’t find an ‘active scene changed’ callback in the API so far)
Thanks!

You can just create a new workspace and switch workspaces using Ctrl + Page Up or Ctrl + Page Down

This used to be the default in Blender 2.7x, apparently they removed the function entirely, Here is a workaround:
How to assign different scenes for workspaces in Blender 2.8?
He creates a new window and instead of switching workspaces, he switches windows (ALT - TAB)

ah, shame. thanks for the workaround


text:
Posing: only one object moving, incorrectly
Apologies if I missed something. Newbie to Blender, none of my searches have helped yet. Perhaps I just don't know the proper terms.
I finished a model, finished (I thought) rigging, and after setting parents with automatic weight only one object moves, and even then not properly.
For instance, it's the knee brace:

I try to bend the leg, and only the brace comes along for the ride. Even then the bar on the side either remains straight like pictured or just stretches to the underlying face.

Confusingly, the other side bends properly at the center. They both have separate faces for the top and bottom halves.
Edit: A friend suggested turning on Bone Constraints.
Which fixes the biggest immediate problem. Still need to figure out how to adjust just what follows which bone and how, and... apparently scrape gum off a foot.

The file:

perhaps share your file: https://blend-exchange.giantcowfilms.com/

Nothing so far?
I've been trying everything I can find, no improvement yet.

First I think that the armature is not well organized, you need to give an IK constraint to the shin, with a controller behind the heel, and also the rigging is bad, and you need to correct this in Weight Paint mode and with the Vertex Groups of the mesh. But perhaps you should follow more tutorials on rigging in Blender, there are a lot.

Alright, that's a great direction to head. Not many of the tutorials dipped into that yet, and without knowing where the problem lies, I hadn't switched gears yet. Most were 'select mesh, select armature, parent with auto weight.'
Now I know where to point my searches, and can find the tutorials that help there. Thanks.
Heck, wouldn't be opposed to going back a few saves and manually setting up vertex groups if need be.


text:
Render Layer - Blender 2.8
I try to change my workflow from Blender 2.79 to Blender 2.8, but I struggle with the new layersystem. In previous versions you could go to the 'Outliner' window an say to each object by click if it should be shown in the viewport, if it should be restricted from the viewport selection or if it should be renderd. Simular option I also discoverd in 2.8, but how this works together with the new View Layers and how to get renderlayers from different View-Layers. As far as I discoverd it, the 'View-Layers', as a kind of a group of objects, work simular to the old 'Layers' in 2.79. In the Propeties-Window in previous versions you could find the tap 'Renderlayers', an there you where able to group different Layers to one Renderlayer, and use the different Renderlayers in the Compositer, but this last steps, beginning with the creation of Renderlayers I couldn't find in 2.8 and also how to use layers as masklayers like in 2.79.
Is there anyone who had the same problem and could finaly solved it?
Thanks in advance!


text:
Timeline cursor missing
My timeline cursor in the video sequence editor is either missing or hidden. I reinstalled blender to no avail. How can I get it back?

Edit: I found my timeline cursor as here, but it won't move at all.

I found my timeline cursor as here, but it won't move at all.

In Blender you cannot do that with Left click, you have to Right click and drag the cursor around your timeline.
Hope this helps.
All the best..


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How to add "Sag" to cloth simulation?
I am trying to create the net of a soccer goal using blender's cloth simulator. Right now the net looks really rigid and unrealistic. The cloth is a plane with subdivision and a wireframe modifier. I currently am pinning it on all 4 corners of the plane so that it stays attached to the goal. How do I make the cloth not seem so tight and rigid and add a bit of natural sag due to gravity?

I’ve tried to re-create this behaviour and I get the sag as expected - so I don’t know the issue in your case. Check your pinning to ensure that only the expected vertices are in the pinning vertex group. If that doesn’t help, can you upload your blend file so someone can examine it?

@RichSedman I have included the Blend file.

Your file is sagging nicely for me @Jacob Edie

As mentioned by @Coffeehouse, your file seems to 'sag' as would be expected. I have tested this by downloading your .blend and simply running the animation from the start, using Blender 2.76. Please re-try and let us know whether this is working. One issue could have been if you were still in Edit mode when you ran the animation or baked the simulation as this would have still kept the mesh in its initial state rather than showing the simulated result.

Thanks for the help I did not know how to clear the baked simulation. It now sags for me as well!


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Alternate methods to adjust brush size/strength for sculpting?
I'm using Blender, and I'm trying to use my Ipad tablet with Astropad to do digital sculpting. I'm running into an issue trying to adjust the size/strength of a brush without having to move my left hand from the keyboard, or my right hand from the tablet.

Normally, you would press F, drag the mouse left/right to adjust the size/strength of the brush, then left-click/press Enter to confirm the change. However, with my tablet, as soon as I put my pen to the screen, it automatically "clicks" and doesn't give me the chance to adjust before confirming. This forces me to either use a mouse to adjust the size, or take my left hand off the keyboard and touch the screen to simulate a hover, which isn't convenient.
Ideally, I would like to disable confirm on click, so that I can drag the pen on the screen to adjust the size/strength without relying on "hovering". I'm having trouble figuring out how to do that though. I found the radial control settings for adjusting the settings of a brush, and I see a "confirm on release" option, but that only makes it so that it confirms when I release F, it does not disable confirm on click. Is there a setting or action to disable confirm on clicks in radial menus?
Alternatively, is there a way to adjust the size/strength of a brush using an ndof controller such as a 3d mouse, as opposed to a regular mouse? I have a 3dconnexion space mouse, and if possible, I would love to adjust the settings using the knob on the 3d mouse instead.
Thanks.

The brush settings such a radius, strength, pressure, and a few other things, can be changed by the context menu. Just right-click to open it. (I hope this helps with the pen issues):

If you can't right-click with the pen or you have chosen the "right-click to select" option, then the default key to open the context menu is W. But in Sculpt mode there is a keymap conflict (Blender 2.93), because the new Face Set Edit pie menu also has W key assigned, and wins. To be able to open the context menu you need to change one of the key bindings.
If you use "left-click to select" (default for Blender 2.8+) you don't need to change anything.
Keymap/Key bindings can be found here (or search for key-binding: W):

main menu File > Preferences, section Keymap, then 3D View > Sculpt > Sculpt (Global) - (It's a huge list)