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Particle system not linking particles at the object origin
I'm attempting to make a cherry tree in blender, but the particle system displays all of the cherry blossoms inside the branch despite their object origin being on the very tip of the stem. How do I get the particle system to start rendering it from the stem instead of the middle of the flower?

It sounds like you're doing it correctly. Could you post your blend file?

Sure! https://drive.google.com/file/d/1SJNyxfsKA-wbMGBmGN37Am9u1w_MdbDe/view?usp=sharing

Okay it looks like the main problem is actually pretty simple. The particle system is set to render from the collection FlowerBunch1, but it looks like Bunch1 is the collection you've been working on. So changing that fixed the worst of the problem. (You can also check Pick Random so it randomly selects a blossom in the collection instead of cycling sequentially)

As an aside, the collections listed with an F (including FlowerBunch1) have a fake user (see also: term in 2.79 manual) keeping them in the blend file, even though they aren't in the scene anymore. If you want to remove these entirely (and you're sure they aren't needed or referenced elsewhere), you can switch the outliner to show the blend file, then right click the collection to delete it from the file.

Or alternatively the fake user can be set/removed in the ID Data sub-menu and the collection added back in with Link to Scene.

At this point the blossoms should be mostly connected correctly. Just make sure to check that all the objects in the collection have their origin where you want it to connect to the branch. The bent blossom Circle.006 is a touch off, and the large bunch object Circle.004 is a little disconnected. It may need to be modified to have the stems come together closer to its origin, so they all appear connected to the branch.

And this goes a bit beyond the scope of your question, but the rotation of the blossoms is also making it hard to tell sometimes where it's connecting. Here's a couple suggestions as a starting point, but do whatever will get the results you're looking for:

Rotating the blossoms to be aligned with the X axis allows the particle system to know which way the blossom is facing

Orienting the particles to the branch's normal so it points outward. Using a bit less random rotation, but with more random phase (spin).

Note: To keep it simple, I removed the bunch (and the empty) from the collection Bunch1 for these examples, so that only the single blossoms would be added to the tree.

Perfect! That makes a ton more sense. Thanks much


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How can make objects invisible in only certain areas?

I started to study blender recently, and I was just making some experiments with fluid simulation but I was stuck with this problem.

You can use the boolean modifier to achieve this. Put it after the fluid simulation modifier for the domain object, set its operation to difference and the target object to the region you want to hide.

source: Stack Exchange

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

sort: votes


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Objects Rendering Black in Blender Render
Now, I just got blender yesterday, and every time I render an animation, the objects always render black.
I have looked up stuff about it, but most of them are UV Maps, and I don't know what that is.

Hi, Jayson. Add lights to your scene.

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


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FBX file to video conversion
I have all my action files in .fbx format. Usually i import to Powerpoint and Export as Video with Green background so that i can remove the ChromaKey in my video editor to have the animation.
Please let me know if there is a way to import the FBX file and then take an output video or any workflow in BLENDER that will let me take my character do animation in my videos.

The fact that he imports an .fbx into PPT should already give you shivers down your spine...

Lol... Friend, very new to 3d world.  This is my work flow

Create a character in MakeHuman software.
Export as .obj file after modelling. It gives you 1 .obj, 1.mtl and a texture folder. Zip them all.
import that zip file in to mixamo.com. You can animate the characters in minutes
Download any animation as .fbx file with skin
Import that .fbx file to Office 365 PowerPoint
File export as video from Powerpoint
https://www.youtube.com/channel/UCNT7WQMdlgFnevMERzSrt_Q

With step 5 got broken, I am seeking help from Blender to continue this workflow.


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how to place video inside of an image
Very new to blender so be gentle. I am more looking for a direction to follow then an exact how to but obviously that would be useful as well.
Problem:
I am creating a YouTube intro sequence for my gaming community and one of the idea I have is to make the camera pull back from our clan logo.
While its doing this I'd like to have small sequences of recorded gameplay appearing within or almost reflecting off logo until the entire logo is revealed, something like this GoW clip (3:46-3:51)
Is this possible, and if so what area should I be researching to make it happen?
Thank you in advance for your time

what render engine are you using?

I have swaped between Blender Render and Cycles render testing each of them out

You can use video or image sequence exactly the same way like texture.
In Node editor:
"Shift + A" -> "Texture" -> "Image sequence" (select all images "image.000" - "image.xxx").
Or you can choose "Texture" and open video file exactly like image.
Now you can setup video texture offset and start frame.
Start frame: when video start playing (timeline frames)
Offset: set first frame where video start play (video texture frames)
Example:
You need start playing video texture on frame 1250 of your animation and you want to jump on 10th second in your video texture. (remove first 10 second from video texture)
Set Start frame to 1250
Set offset to 240 (for 24FPS: 24 x 10 second)
There are also "Frames" - you can use it for stop play video texture. Frames = video texture frames, not your animation frames on timeline.
Second option is using Material ID for creating mask and add video to object using this mask in Video Sequence Editor or in Compositor.
Personally I thing the 1st option is easiest way how to do it, just play with setup to achieve what you need. :-)

It took me awhile but I believe i have made it work using your first option. thank you.
The only problem I am having now is scaling down the video to appear correctly in the available space. I corrected this for now by enlarging the area but I am curious if there is a better way.  Here is a link of what I have so far  using trial footage. I would like to either place different footage in each of the 3 workable areas or simply keep it as is.
(I'm sorry for the formatting, I have re-posted this comment 15 times with no change)

As a first you need to unwrap object (as you know :-) ) In this case I recommend use "Project from view" while you look at object through camera (zero on numpad) This make rights coordinates for you. Now in material you can add: "Shift +A" -> "Vector" -> "Mapping" and "Shift +A" -> "Input" -> Texture coordinate.   For better Imaginations: https://postimg.org/image/pdv93dss1/

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


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Subdivision modifier working on part of mesh in Cycles, but not the rest
In this Blend file of a fire extinguisher I am making, the subdivision modifier is working like expected on the tank, and the top of the tank, but when I tried to add the handle, in Cycles it seems like the handle is not being rendered correctly and looks blocky, not sure whats going on. Any help greatly appreciated.
Strange thing is, if I go into wire-frame mode, in the viewport it is showing all of the added geometry and in solid mode it looks how it should, but when rendered it is blocky.

what do you mean by "blocky"  ?

If I do a render with the current camera view, it looks ok, could you please show a screenshot of the problem?

Hey thanks for the quick responses. I actually seem to have fixed it. I got frustrated and removed the subdivision modifier and then added it again and now its rendering just fine. Anyone know why that would happen? Also, is removing a subdivision modifier and adding another one bad in any way for my mesh?

Iagree with @moonboots, maybe right click > shade smooth will bring satisfaction.

I'll try that next time I run into that problem. Thanks a lot guys.

edit: yes it might be what Edmond says, when you shade smooth an object but join another one to it (ctrl J), the new mesh won't be smoothed and you need to redo a shade smooth, I don't why it's necessary though

I'm voting to close this question as a bug, since (1) your file doesn't show any problems and (2) readding the subdivision surface modifier with the same settings has a different (correct) result. Keep in mind that Blender 2.8 isn't released yet. If it would be possible to reproduce the error, please report it to the bugtracker.

Can be closed. I can't reliably recreate the problem even though it does still happen infrequently. Reapplying subdivision seems to fix it.


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Question about workflow
I have been fiddling around with blender on and off for a while now (I'm still a complete noob.)
My question is about workflow, more specifically what should be done in which order. Obviously you have to model your object first then texture it. But what about stuff like baking? Do I need to do seperate bakes for each thing? Like AO, high poly mesh bake onto low poly mesh? Any help would be appreciated I find most tutorials have little to no explanation about why you are doing things in a certain order and the order is different between tutorials.
Thanks in advance, everyone.

I would say that it is based on experiences. The workflow may be similar in overall structure. But in those detail, depend on artist behavior. Some might need a cup of coffee for doing something tiring, e.g. weight painting. So he might do other thing first in order to adjust when to do the specified job. And of course, based on what is the goal of your work, it will lead to different workflow.


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Animate ejecting bullet brass
Ok so what I'm trying to do is animate what the title says. I've got my shell casing modeled but I cannot get the fine tuning of the ejection animation proper. I've toyed with rigid body simulation just allowing the casing to drop and collide with a plane so well as particle system emitting casings from a plane not visible in the camera frame. Issue is either way I'm not getting the realism. With particle system I don't get the collision on the plane right seemingly no matter how I tweak things and with rigid body im getting no vertical propulsion of the casings but a decent enough collision with the plane. Has anyone else ever animated this simulation and has advice to offer for methods and tweaking?

I think you need to upload a gif or something to show what the problem is with the simulation. Try do describe what you are referring to when you say Not realistic. Rigid Body simulations should be the way to go but they might need some tweaking.

I'll screen record when I get home and upload a short video. My problem with the rigid body method is I get no vertical projection as the casing is in air. Just a straight down drop


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Strange shading after OBJ import
I have strange shading after importing an obj file:

When I zoom in, the face seem perfectly flat. I checked normals, they are ok. I also tried the "clear sharp" function, nothing changed. Also tried "remove by distance" but no vertecies were deleted.
I searched a bit around here for an answer that already exists, but shading issues are dime-a-dozen with very specific issues, non of them helped me.
Does anyone know what's the problem here and how to fix?
Thanks in advance!

You cleared custom normals?

@scurest sorry, I don't know what that is about... can you point me towards a resource where I can learn about that?

This.

@scurest Beautiful! That did it. Very simple.

I fixed this by clearing custom normals.

I had something similar. In object mode under the object menu I changed the setting from "shade smooth" to "shade flat."


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Separation into different objects fails
For practice I am trying to model an object and need to duplicate and move a face (similar to the way it's done in blender guru's doughnut tutorial for the icing).
So I marked the faces I want to duplicate:

...used shift + D and then moved the duplicated face:

...and then used P and "selection" to make its own object out of it:

However, as you can see in the last image, the separation somehow fails. Its marked in red and I cannot do any transformation or so to the new object.
Does anybody know what's wrong here?
Thanks in advance!

did you release the object after shift D or right clik?

Once separated. Go back to object mode, unselect everything (click in a large empty space) then re-select the object you want to modify.

"However, as you can see in the last image, the separation somehow fails." The last image shows two cylinder objects in the outliner, which specifically indicates the opposite

After you separate (P), be sure to exit Edit mode on Cylinder.  Otherwise you won't be able to select anything in Cylinder.001.   So 1) Separate; 2) exit Edit mode; 3) select Cylinder.001; 4) enter Edit mode on that selected object; 5) make sub-object edits.   Forgetting to exit Edit mode is the bane of my existence!

James and Christopher, thanks! That solved it!!

@ChristopherBennett, since your answer was first, I'll click accept if you post answer. Thanks to james, too, though!

It's ok. You posted an answer to the question - that's all that matters. Don't forget, you can "accept" your own answer by clicking the checkmark. That way others know it's the correct solution.

As @james-t and @Christopher-Bannett wrote in the comments, edit mode needs to be exited first and then re-entered under the new object.
Thanks guys!!


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move vertex on plane / face
I'm being frustrated by this simple task: I want to move the marked vertex, but it's supposed to only move on its surface. Reason being, I want to subdivide the surface into a specific shape. ...Tried for hours, searched online for hours, just couldn't find it out. I assume its more simple than I think it is, but I just can't get it to work. Can you help me?

Thanks in advance!

Change your transform orientation from Global to Normal then grab the vertex with G and restrict it from the local normal Z-axis by holding Shift and pressing Z

Thanks a lot, that did it!

No problem. Don't forget to switch your transform orientation back to global afterwards or at some point, you'll wonder what the heck is happening later on.

The vertex is part of the overall plane?  Select both faces.  "Create orientation" operation (ctrl alt space for me.)  Select the vertex and translate it constrained to XY (g shift-z move mouse confirm for me.)


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Showing the object xyz axis lines via python when moving an object
In Python selecting an object does not display the axis lines, bpy.data.objects['Cube'].x = 5 simply moves the object.
I've tried injecting keystrokes like  G  + X after object is selected but didn't succeed. Is there a way to display these axis guidelines via Python ?

It sounds like you’re talking about the move gizmo? Everything stated seems to be expected behavior.

If you want to permanently show an object's axis, you can use bpy.context.object.show_axis = True. It's in Properties Editor > Object tab > Viewport Display > Axis.


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Blender 2.81 render not using all GPUs
I have 2 Nvidia GTX Titan Black graphics cards in my machine, but Blender keeps using only one of them.
I have them both checked in the Preferences > System > CUDA tab but when I render and take a look at the Windows performance screen only one of them is in use.
I´m using Windows 10 and blender 2.81, my graphics drivers are all updated. Anybody have any idea what the problem might be?

If you're using Eevee, multiple GPU rendering is not supported.

I had a similar problem a while back with cycles. I used a script for rendering on remote ubuntu systems with titans xps. Try running the following script IF you too have Titan xps, otherwise try to find the right blender-name for your GPU  first. This may or may not work, I thought you may want to give it a shot.
import os, bpy

os.environ['CUDA_VISIBLE_DEVICES'] = '0,1'

bpy.context.scene.render.engine = 'CYCLES'
bpy.data.scenes["Scene"].cycles.device = 'GPU'
bpy.data.scenes["Scene"].cycles.feature_set = 'SUPPORTED'
bpy.context.preferences.addons['cycles'].preferences.compute_device_type = 'CUDA'

cprefs = bpy.context.preferences.addons['cycles'].preferences

# Enable all CPU and GPU devices
for device in cprefs.devices:
    if device.name == 'TITAN Xp':
        device.use = True
    else:
        device.use = False

# Tests
print('Compute_device_type: ', cprefs.compute_device_type)
for device in cprefs.devices:
    if device.use == True:
        print('USED: ', device.name)
    else:
        print('NOT_USED: ', device.name)
print('Will be used: ' + bpy.data.scenes["Scene"].cycles.device)
print('Feature set: ' + bpy.data.scenes["Scene"].cycles.feature_set)
print('Render engine: ' + bpy.context.scene.render.engine)


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How to flatten a curved object
I have a complex mesh of a piece of clothing that I want to flatten out so that it looks like it has been taken off.
How can I do this while keeping the detail of the mesh? I have tried with a Curve Deform modifier but it won't flatten a curve, only curve a flat shape.

I don't think there is an easy way to unwrap or flatten a crumpled or wrinkled mesh object. Maybe look into Laplacian Smooth or Smooth modifiers, but I do't think that will be enough.

If you're looking for a way to make cloth which is flattened because it lays on the surface then Cloth modifier is best solution.

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


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Gradient multi color each face?
Basically I want to make gradient color like this in cycles, is that possible ?

Here the link for the lowpoly apple model I made:
https://drive.google.com/file/d/0BzM1zdTMJ5ombC1BNmN5VmJyemM/view?usp=sharing
Thanks you

You can use faces normals to obtain the colors of the faces (more or less randomly) and use UV input to give them a little gradient effect (or some lamps also).
For the color :

Use "texture coordinate" and "normal" as input
Add a vector mapping (this is usefull after to tune the faces orientation by rotating x, y or z and change the colors)
Separate the coordinates
Add a color ramp to each so that you can modulate each intensity
Combine them and use it as a color input for the shader

For the little gradient effect :

Use "UV" input of the texture coordinate input
Separate and use X or Y (U or V)
Add a color ramp to tune the value

Use both by mixing them and link to the shader.

This is not the exact same colors as your picture, but the same kind of effect. You'll probably have to tune : color ramps, orientations, eventually inverting X, Y, Z...


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How do I Inset a face equally?
How can I inset/extrude a face, so that the outer faces have the same width?

Any kind of help is appreciated

You have to Apply Scale to your mesh first in Object Mode.
Ctrl+A > Scale.
Now try I to Inset Faces again.

Thank you so much, still worked for me in 3.0, 6 years later FROM THE FUTURE!

You can use the Inset Faces tool, which you can activate by pressing I. Do note that this won't work if the object was scaled in Object Mode.

You scaled your object in object mode. If you want to have the inset work properly, you will have to scale the plane or what ever you are starting with in edit mode, or apply the scale if done in object mode. When you scale in object mode you are making it “look” correct, but it won’t be correct unless your editing of shapes are done in edit mode or applied in object mode.
The top rectangle was scaled in the X direction in object mode without applying the transformation then the inset was added. The one on the bottom was scaled in the X direction in edit mode and then the inset was added. If you apply the scale in object mode to the top rectangle in object mode then do the inset, you will have the same result as the bottom one.
Remember, transformations in object mode are what you want it to look like, but transformations in edit mode (or that are applied using Ctrl-A menu in object mode) are what it is like.


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Blank image when I render
I went to animate a project, Blender was returning a blank screen.
I have attempted to restart both Blender and my laptop, as well as re-downloading the program.
With each attempt, Blender exported a black movie, which I attempted to watch multiple times.
I even attempted to reanimate one of my older Blender files, and even that reexported as a black movie.

Old File

Newer File

@cegaton Aha! You've made me an inch smarter, thanks. Strange i didn't notice when comparing it to a working .blend. Also i'm going to bed now so you can fill in a answer if you wish, if not i can do it tomorrow.


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How to use a custom property of an object as input for a driver?
I would like to be able to control the power/energy of multiple lamps using a driver.
My idea is to have an empty that I would move on the Z axis between 0 and 1 to multiply the energy of each lamp.
On the lamp power attribute, I have Use Self enabled and this driver expression:
self.energy * var

Edit
It seems to provoke a kind of expression loop, and the value is increasing exponentially.
So I guess my original "power" value should be defined elsewhere, maybe as a custom property of my lamp object ?

How could I link one to my driver expression?

IMO at issue here is self.energy is the power field you are driving. I don't get an error for this, but do get a constantly growing result.. which may lead to an error.  See https://blender.stackexchange.com/questions/46903/how-to-view-python-error-messages re seeing the error message given, and post into question.

"This question already has an answer here" - nope, does not work with autorun python scripts.

Please post the error message printed into system console into question & will re-open.  Please also take other note of my comment above in that you are driving the property with itself.

@batFINGER you were right. I edited the question.

whoops voted .. meant to give it a python tag first. Will need to wait on other re-open votes. Was an error message being printed to the system console. Don't get that ... end up with Inf or Nan (Infinity, or not a number as result) .. Re custom prop. Add one to lamp (data) called "prop"  replace self.energy with self["prop"] in expression above.

it says "key 'power" not found. I do have a "power" custom property set.

Make sure it is a lamp custom property, not a lamp object custom property, or scene or viewlayer.  Select the lamp object, in python console type in C.object.data["foogle"] = 1   There will now be a custom property on lamp named foogle.  Your screen shot above suggests you are in object tab of properties, not in data tab. C.object["foogle"] instead of C.object.data["foogle"].   The self in driver for this case is C.object.data  Or in UI terms First screen shot above (where driver is), is in data tab. Put the custom prop in the that ones "Custom Properties|".

this time I got it working ! thanks a LOT for your help here.

@Timaroberts please re-open, Have added an explanation via answer in linked dupe as to why.


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Normal map seams SFM import to Blender
Just to preface I'm new to blender and all 3d software. I have an object I imported into blender from SFM. I notice on some objects that there are seams when the normal map is used. Even if I just load a blank image, there are noticeable seam issues when a normal map node is connected.
I'll share several images to show what the issue is. I've tried converting to quads, removing doubles, recalculating normals and nothing seems to work. I've tried texture painting them but it doesn't work for these seams. I've manually selected faces and flipped normals and it still has a seam.
All normals are facing the right way. The normal map itself doesn't have seams (if I view it in texture painting). I imagine it's an issue with the UV mapping but I'm not sure I can fix it without a deeper understanding of UV mapping.
The first image is the normal map and texture applied showing the seam:

The second image I removed the normal map texture but there's still a seam and shadow issue:

In this image I disconnected the normal map node and it has no seam.

Here's the mesh polygons, no messed up edges or anything:

No normal map or texture, mesh looks fine:

In the final image I have no texture and no normal map texture, but the blank normal map causes these messed up seams.

For this particular model it's not really a big deal, but I have some human models that the same thing happens on. Is this just an issue of the original source or is there any options I can change to fix the issue?

The last pic with the empty image texture connected to the normal node is always going to look wrong, the colour used for a missing image is not the same as the 'neutral' normal map colour so it will always distort normals.


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Texture painting issue in 2.9+
I've been using blender a while but I don't texture paint often. I'm unsure if there is some new options in 2.9+ or if this is a bug, but my texture painting is all jittery and weird. Also sometimes it just paints big squares instead of the brush. When I open the exact same file in 2.83 it works fine. I've included a video of the issue. Are there any fixes?
Thanks!
https://www.youtube.com/watch?v=grwG99gzmuE

I found the issue. It was the texture size viewport limit setting that wasn't active on my 2.83 version.


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Animation doesn't update when switching action strip in 2.91
I'm not sure if this is a bug in newer blender versions, or some option that needs to be enabled. In the past when I would move up or down in animation layer, the rig/animation would change immediately. Now I have to either select bones or move the action strip to force it to change to the new animation. The issue affects any scenes I've been making since 2.91.


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Render slows down in the last couple minutes
Beginner here. I started a few days ago and began using blender 2.8 yesterday. I'm not sure if it's normal but I notice my renders slow down in 2.8 when they're almost done. It didn't happen in 2.79. It's so much that the last 1 minute of time remaining takes 10 minutes. The image is also almost completely rendered, with almost no tiles showing any noise.
I have GPU and CPU rendering set up, my GPU is a gtx1080 and CPU is in i5-4670k at 4.5ghz. Not sure if that's relevant but thought I would add it.

Everything is just simple.
i5-4670k heve 8 logical cores wich one by one render slower that one GPU.

Can see, how GPU overtaking CPU cores. And then they remain, but the GPU is not involved in process. There is also an inaccuracy in the calculation of time.
It would be better if the CPU represented only one tile. I have posted about it on developer.blender.org.
You need to render only by GPU and it will become faster then with CPU.

Thanks man! I had tested it earlier and you're for sure right. My render was 18 minutes with just GPU vs 27 mins with both.

@nnostad23 Don't post thanks as a comment, if the answer helped you upvote it, and if it completely solved your problem consider marking it as accepted


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Can Blender in sculpt mode apply a stroke 360° around an axis?
Can Blender somehow make a ring around the sculpt in the axis i want when i tap a brush on it?

Sculpt brushes have Radial setting, see https://blender.stackexchange.com/questions/107635/symmetry-in-sculpting

Radial symmetry will allow you to do exactly that, just increase or decrease the number of steps and change the axis to suit your need.


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Why mirror modifier does not merge?
Goodmorning, I am working to imitate the tutorial at this link:
https://www.youtube.com/watch?v=QbSmoZCrP8I
At minute 5:15-5:30 he creates a circle with 8 vertices, deletes 3/4 of the figure and then use the mirror modifier to complete the operation.
I'm trying to imitate him, but after deleting the 3/4 of the circle I apply the mirror modifier but the circle does not close.
My result is:

Instead in the original tutorial the circle is:

I don't understand where is the problem.

Note that he rotates the circle in edit mode. You have rotated your circle in object mode as you can from the transform values in the top right of the 3d view. You will have to apply the rotation now (Ctrl A).

Thank you, now it works!

First he added a circle consisting of eight vertices that was rotated by 22.5° on z-axis in object mode. The quarter circle was made by inserting a vertex on each side to align with the axis and then deleting the rest. You can use CTRL+R then point and click at the space between the circle vertices with your mouse to create one vertex in the middle.

It's the same operation I've just done, I followed his path but I don't understand why the result is different.


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why blender motion track didn't render the movie?
I build a motion tracking animation, but the render result didn't shows my video. I make sure my nodes are linked right. what's wrong with my animation? please help me!

Make sure that you have Transparent enabled in Render Settings > Film.

ohhhhh thanks! you helped me a lot !


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Viewport gizmo buttons not visible on Macbook pro (Blender 2.80)
I downloaded the latest Blender (2.80) today for my Windows computer aswel as for my Macbook Pro. On the Macbook the Gizmo to rotate the viewport is visible but not the 4 buttons left to it (perspective, camera, move and zoom). If I toggle the "Navigate" checkbox in the viewport gizmos options from the menu above on my windows machine then all 5 buttons appear/disappear, but on the Macbook only the rotate button appears/disappears. Is there perhaps another setting iI have to check somewhere?

Strange, activating navigate should also bring all the other options as well. I don't have a mac so I can't test this unfortunately.


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Is there any way to get single pixel wide aliased lines?
I'm trying to get clean, one pixel wide lines on my renders like the pic below, but nothing I try seems to work.

I've tried freestyle with one sample, but I get extra pixels at some parts of the strokes and the low sampling makes the rest of the render look really bad.

I also tried this compositor nodegroup and this script, but I can't make the nodegroup's lines thin enough and the script just doesn't work at all.
These were the thinnest lines I could get with the nodegroup.

So is there any way to render lines like the first pic, or am I out of luck?
I'm fine with using either engine.

Have you set the pixel filter to box (Render Tab > Film) when you're using Cycles?

Just tried it, this is what I got

Was just an idea, because that disable anti-aliasing.

I can get similar results to my second pic by using the other two filter types on the smallest width, but they still aren't as clean as I'd like.

If you're ok with using the Workbench engine, you can simply go to User Preferences → Viewport → Smooth Wires and disable Overlay.

You can choose the Workbench engine just like Cycles or Eevee in the Render Properties tab, and since frames can still be rendered with transparency you could easily composite them into frames rendered with any other engine.

Result

I totally forgot about this, so I apologize for the late reply, but thank you! That's exactly the look I've been looking for.


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Blender Hair Simulation is making a Wall
In Blender 2.8, I made a grassy area and used hair simulation to create the grass. The only problem is that it seems to have created a wall on the edge of the plane. I have also noticed that as I increase the number of hair strands, the wall grows taller. Does anyone know how to fix this?


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Why do I have a strange kink at the edges of the tiles?
I'm using Blender Render, a 90° FOV Camera. My Tiles are 512x512.
But when rendering, there is something strange happening at the edges of the tiles. Does anybody know something about it?

Ah, i found the problem myself!
I set the camera to Panoramic instead of Perspective
Now I changed it to Perspektive and the edges are gone.


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How to make an object "move towards" another object
I have my camera tracking an empty and copying its movements. i want the empty to move to a button when it is clicked on, but i dont want the empty to turn at all while moving. just move straight at the other object. I had some basic java "training" with Alice and there it would have been as easy as saying move towards object for some duration or move to an object, but looking up the right command in python is something im still struggling in. i can make the empty move in coordinates or face the object and then move, but thats not what im looking for. This is in the Game Engine and i was looking in game logic. (bge.logic)

I'll admit it has been years since I've done any coding with the bge. But I would suggest looking up vectors. Get the vector from your empty to the object Then set the magnitude of that vector. Something like this:
vectTo = empty.getVectTo(object)

vectTo.magnitude = 2.0

empty.position += vectTo`

Like I said its been years and I don't have blender convinent to test (im really not sure that will compile) but something to that effect should work.

oh and just to be clear. Setting the magnitude gives it its speed. Skipping that step would make it teleport right onto the button. you might what to have a variable speed. setting the magnitute to empty.getDistanceTo(object) might be helpful. Whatever you want to do


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Problem with Scaling
I am learning to make an alarm clock but the problem is my scaling is not happening like the one in the youtube video am learning from. My scaling was supposed to be like this  , but it's coming out like this, all selected lines r scaling together it seems

You have Proportional editing mode enabled !
In this particular case you probably don't want that when scaling.

Just to add: the keyboard short key for toggling Proportional editing on and off is the O key.

Worked. Problem solved


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New to UV maps and unwrapping in general, need help
I'm trying to unwrap a simple model so I could texture paint it. However I really don't understand the process of how to unwrap a model, especially the whole marking seams thing. I only use Project From View, which I think is not optimal when unwrapping certain models (especially complex ones). I've watched tutorials and can't seem to get the gist of UV unwrapping. I'm trying to unwrap the inside of the model, but it gives me weird shapes and sizes. Can anyone tell me how can I unwrap the inside of a model? or better yet, unwrap in general? Thank you!
Here is the picture for reference:

Here is also the .blend file in case anyone wants to show pictures of properly unwrapping this model:
House WIP.blend

UV unwrapping can be an art in and of itself. If all you are doing is texture painting in the 3D view, I would recommend just using the Smart UV Project. The advantage is that this will unwrap your model sufficiently so you can paint in the 3D view. The disadvantage is that the 2D layout of the UVs won't be very intelligible, so you won't be able to paint in the 2D view. If you only plan to paint in the 3D view, this will work fine for you.

Well, I was planning to have my textures painted in Photoshop since I'm more comfortable than in Blender's built in painting stuff.

Ah right. Well yes, then you do need an ineligible 2D result. Looking at your model though (lots of sharp angles) you might get a fairly good result from the Smart UV Unwrap option. Give it a go, see what it looks like (save first, as it will erase you existing UV map).

If you are more comfortable with the Project from View, then select all the faces on a side and then project them at the same time, and then place them off to a side of the uv editor away from the center of the view. Repeat until you have all your projections, adn then when you select all your faces you will see all the uv islands there in the editor - you can then arrange them and scale them so that you might better understand in Photoshop.


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Is there any way to fill the whole back of this mesh?
I'm modeling a shield and got stuck with a problem. I want to fill the whole back of the shield mesh, but can't figure out a solution on doing so. I can't just press F to fill since all of them are individually modeled, but all of the vertices are aligned. I've attached a screenshot bellow

Since they all are individually modelled the only solution you are left with if preserving this model is to fill them individually. So select piece by piece and fill the back side preferably with quads. Or you could remodel this and have another way

Hoo boy.
Ok so before I suggest something to solve this at this stage, id like to really reconsider your workflow in modeling: Fill first, extrude later. Also: do not intersect geometry (non-manifold meshes)
For this case i would say that maybe if you used the "Grid Fill" feature you could fill the faces to make sense on automatic (space -> search: "grid fill").
Otherwise theres always the soul-crushing way of doing it by hand: quad by quad (have fun)
At this stage id just trash what you did here, and restart the whole model with the elements already filled and then extrude them. It doesnt look like too much work.

Thank you. It seems my workflow is not the ideal one. Also can you elaborate more on fill first then extrude later? So if I were to remodel it again, I shouldn't extrude first but rather fill it first. How about when I individually model a part? Let's say the upper part is bigger than the lower, how can I fill it both with only one face? I hope I made sense.

Just start working with a plane and then subdivide/loop cut as needed to create the shapes, then extrude. If you always start with just the outline, you will get problems with filling it, as the fill just makes one huge N-gon and not quads, which then cant be cut or subdivided properly. In effect you will get a messy topology thats not flexible for further edits.

I see. I've been doing ctrl+click (add vertices) to make an outline of my desired mesh then just fill and triangulate and/or knife tool to get rid of ngons but it seems its easier to just model from a plane.

The process to make this work with F (Fill with NGons) or Alt-F (Fill with Tris but this can "detect" holes) will be quite tedious.
I would say remove the extrusion loop and work your way to make it manifold. The fill an then extrude.
Or maybe start from scratch and use your current design as template to trace a new modell the right way.

You would first have to clean up the geometry to avoid all intersections. If that is done and you have the finished part of the mesh completly manifold, connected and non intersecting you would then press Alt + F to fill it with triangles

I guess I'll be starting over since I really want a clean mesh. What would be the best approach if I were to model it from scratch. I use the add vertices (ctrl+click) to make the parts. How can I avoid multiple parts for a cleaner look? Thank you.


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How can I have multiple animations with different end frames?
I'm making a simple character for a game in Blender and have 2 animations so far. One is the walk animation which only has 24 frames while the other is an idle animation that has 29 frames. How can I make the walk animation not go beyond the 24th frame? Thanks!

As you said walk animation has 24 frames so it should not go over 24th frame anyway, imho... Also you didn't say it was about exporting to Unity... !

Apparently, Unity automatically cuts the animation depending on the last frame. Why haven't I exported it sooner to check lol.


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FBX import error
I have trouble with importing fbx file created in MotionBuilder. I have file created in MotionBuilder which I can import in 3ds Max and Unity easily, but when I trying to import it into Blender I have an error
And nothing imported to scene. So, anyone know a solution?
P.S. File contains a simple model with skeleton and couple of animation takes.

I have got the same problem. I can't help much other than to say that it IS possible to import rigged and animated characters into Blender... but I just can't figure out the magic method. Some characters/ rigs import fine and other characters I am not so lucky and I get this same error. I am trying to figure out what is upsetting Blender but so far no luck. Also, sadly that link to the BOS FBX is not helpful in this situation as it does not support animation.

According to manual, import FBX with armature seems to be not fully supported.
But maybe community addon BOS FBX importer/exporter can help ? (found here)


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dynamic hair particle stretches while animating the object
i have a fur ball with a  dynamic hair particle and as soon as the object moves in animation the fur on it stretches crazily. need help to fix it.

Images and a .blend file would help others to understand your problem.

@Mentalist i tried uploading a file but it says my file is too large to upload, and how to i add images to the post?

You'll need to remove some things from your .blend and save a version that's smaller. Images can be added from a button that is visible while you are editing your post.


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Can't access some areas in blender
i don't know how i got this problem but my blender has a problem which doesn't allow me to see or use the top part (menu bar by default) and the bottom part of blender; i tried restarting my computer and also reinstalling blender but i still have the same problem. need help; below is the link of image of my blender looks now.

https://i.sstatic.net/QAx1D.jpg

Upload the image to imgur.com or something similar - and be glad people can't just access files on your computer directly! ;)

Please search before posting, this has been asked countless times before https://blender.stackexchange.com/questions/84622/blender-appears-zoomed-in-windows-10

oh sorry i didn't search it right way so never got it. i will delete this post soon; thanks everyone for reply.


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How do I fade in/out an object in Blender 2.8 Eevee?
I'm kinda new to using Blender Eevee. I used to use Cycles, but that took too long to render. I'm doing a text animation with a video in the background, and I want the text to fade in and fade out. However, I cannot do this because Eevee is different from Cycles. Is there any way I can animate the transparency of an object so I can fade it in and out?

Of course it is. The only "catch" is to change Blend Mode under Material > Settings tab to Alpha Blend and turn off Show Backface.
Then regularly you can animate Factor between your shader and Transparent shader (full white colour).

Looked for a solution to this question
Q: Image bleed when using Import Image as Plane [duplicate]
which is linked here.
My proposal:

I put a math node between image and Mix Shader, set it to multiply. Wit the second value set to 0 the image is not visible. Obviously when I set the second value to one it is fully visible.


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Remove/Add Collections per render layer with Eevee
I was able to choose which layer was rendered when using 2.79
Now that things are called collections, and layers are... layers.
I can't exclude collections from certain renders while at the same time allowing the excluded collection to render in other layers.
For example. I have a freestyle layer and a basic render layer. I want some collections to have the freestyle outline, while other collections will remain basic(without freestyle). I'm using Eevee and have not figured out how to do this in blender 2.8

You can assign Freestyle line sets to collections, this would allow you to apply the effect selectively.

For the other part of your question I believe this post should answer your question for the transition between 2.79 and 2.8. The general idea behind the scene and view layer concept is explained in this post on the Blender Developers Blog.
Let's say you have a scene with a collection called "Only once" that you would like to include in one view layer, but exclude in another. The view layer where "Only once" is visible is called "View Layer" and the one where it isn't is called "View Layer.001". You can have the collection "Only once" it both view layers and have it activated in one and deactivated in the other.

In order to exclude specific view layers from rendering in the scene, you'll have to switch to the scenes in the outliner.

If you activate the restriction toggle for rendering you can then exclude specific view layers by clicking on the camera icon behind the collections name.


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Automating a script that I am using to go through each of the indices and weights
So I have two scripts, one that goes through the name of the vertex group and prints out each of that groups weight painting influence.
Another script that goes into Edit Mode, and from the selected group it prints out its Vertex ID.
Both scripts print out the respected values to the console and I wipe the console each time I run the script.
Now I have gotten to a point where I am a bit stuck, I am wanting to automate this process because at the moment I need to do each step manually and this takes so much time.
I currently have 109 vertex groups and manually output both of these these.
Does anyone know how I can go through each of my scripts and make it so the script will go through each of the specific bits of code, go through each group and automatically print the respected values I need, then output that file to a .txt document in a specified folder?
Thank you.
This code snippet prints out the vertex ID
import bpy
import bmesh

from os import system
cls = lambda: system('cls')

cls() #this function call will clear the console

obj=bpy.context.object
if obj.mode == 'EDIT':
    bm=bmesh.from_edit_mesh(obj.data)
    for v in bm.verts:
        if v.select:
            print(v.index)

This code snippet prints out the weight influence of that selected group.
import bpy

from os import system
cls = lambda: system('cls')

cls() #this function call will clear the console

# Which group to find all verts in?
groupName = ' '

# Use the active object
obj = bpy.context.active_object

# Ensure all values updated
bpy.ops.object.mode_set(mode='OBJECT',toggle=True)

# Store the mesh
mesh = obj.data

# Get all the verts
selVerts = [v for v in mesh.vertices]

# Get the index of the required group
indexVal = obj.vertex_groups[groupName].index

# Store the vertex and its weight together.
weights = []
for v in selVerts:      #loop over all verts
    for n in v.groups:      #loop over all groups with each vert
        if n.group == indexVal:     #check if the group val is the same as the index value of the required vertex group
            weights.append([v,n.weight])        #store the vertex and its weight in a nested list
            print(weights[-1][1])      #print the vertex index and its weight

do you want this?
import bpy

from os import system
cls = lambda: system('clear')

cls() #this function call will clear the console

filepath = bpy.context.scene.render.filepath
file = bpy.path.abspath(filepath) + "weights.txt"

wheightsFile = open(file, 'w')  # use 'a' to append

print("weights")
for obj in bpy.context.scene.objects:
    if obj.type == "MESH":

#        print("*"*10, obj.name)

        for vertexGroup in obj.vertex_groups:

            # Which group to find all verts in?
            groupName = vertexGroup.name

#            print("*"*5, groupName)

            # Store the mesh
            mesh = obj.data

            # Get all the verts
            selVerts = [v for v in mesh.vertices if v.select]

            # Get the index of the required group
            indexVal = obj.vertex_groups[groupName].index

            # Store the vertex and its weight together.
            weights = []
            for v in selVerts:      #loop over all verts
                for n in v.groups:      #loop over all groups with each vert
                    if n.group == indexVal:     #check if the group val is the same as the index value of the required vertex group
                        weights.append([v,n.weight])        #store the vertex and its weight in a nested list
                        print(weights[-1][1])      #print the vertex index and its weight
                        wheightsFile.write('%.2f\n' % (weights[-1][1]))

wheightsFile.close()

file2 = bpy.path.abspath(filepath) + "indices.txt"

print("file2 is", file2)

a = open(file2, 'w')  # use 'a' to append

print("indexes")
for obj in bpy.context.scene.objects:
    if obj.type == "MESH":

#        print("*"*10, obj.name)

        for vertexGroup in obj.vertex_groups:

            # Which group to find all verts in?
            groupName = vertexGroup.name

#            print("*"*5, groupName)

            # Store the mesh
            mesh = obj.data

            # Get all the verts
            selVerts = [v for v in mesh.vertices if v.select]

            # Get the index of the required group
            indexVal = obj.vertex_groups[groupName].index

            # Store the vertex and its weight together.
            weights = []
            for v in selVerts:      #loop over all verts
                for n in v.groups:      #loop over all groups with each vert
                    if n.group == indexVal:     #check if the group val is the same as the index value of the required vertex group
                        weights.append([v,n.weight])        #store the vertex and its weight in a nested list
                        print(v.index)      #print the vertex index and its weight
                        a.write('%.2f\n' % (v.index))

a.close()

result:

Sadly not, it does to part of what I am wanting though.
I am only wanting it to list the weights and indices of the selected mesh, not everything in the scene.
I am also wanting the weights and vertex ID's printing out as two separate lists and being outputted as text files, not in the console.
It is kind of there but something I can try and test with.

i updated my answer again. Now it writes two text files in your output directory you specified in render settings

You seem to be doing excessive work for what you are trying to accomplish.
Since you didn't specify how you want the file identified, I've written a function that takes the filename as an argument.  It also allows you to specify which object to run the code on.  Here's an example using the active object and writing to a file stored in the Windows temporary folder:
import bpy

printgroups(bpy.context.active_object)

def writegroups(object, filename):
    if not object:
        return
    if object.type != 'MESH':
        return
    file = open(filename, "w")
    vertex_count = len(object.data.vertices)
    for group in object.vertex_groups:
        file.write(f"{group.name}\n")
        for index in range(vertex_count):
            try:
                w = g.weight(index)
                file.write(f"{index}, {g.weight(index)}\n")
            except RuntimeError:
                pass
    file.close()
    return

writegroups(bpy.context.active_object, r'C:\tmp\somefile.txt')

You don't need bmesh for this, as all of the information is available in the object. Simply change the arguments to writegroups to an appropriate object and file name.  You don't need the 'r' in front of the filename string on other OSes, but it makes the string "raw" so that the backslash characters aren't interpreted as string escape characters, so you can use the '\' directly in a Windows file path.
I didn't place any error handling on the open.  You may want to enclose it in a try/except block in case you pass a file name that can't be created.  Change the "w" to an "a" if you want to append to an existing file.


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Modifiers vanish during copy operation - why?
Blender 4.0.2: I follow the advice in How to add a modifier to a collection? to copy modifiers, but Blender does not behave the way I expected it to:
For one element in a collection, I create a modifier "Mod 1":

Then I try to copy it. I first select the other object, then the one with the modifier "Mod 1".

Then I press Ctrl+L and select "copy modifiers". The modifiers vanish. What am I doing wrong?

The modifier has 0 connections

The answer in the link unfortunately does not mention that the objects are selected in the 3D Viewport, not the Outliner. For an explanation see the answer below by @MartynasŽiemys. As a general rule remember the following: usually the active object is the one which taken into account when copying materials, modifiers, joining objects etc. No matter how you selected, to make sure the correct object is active you can check things like: the active object has a brighter outline than other selected ones. And the top left of the viewport shows the name of the active object.

Copy modifiers operator like many other operators in Blender works by taking data from the active object and then performing the operation to all selected objects.
If you select one object in the outliner and then another using  Shift  clicking, the active object remains the same, so it remains the first object selected, which in your case is the one that has no modifiers. If you then copy modifiers, the absence of modifiers is copied over from the active object to any selected objects. If you want to select and make the last selected object active in the outliner, you would have to  Ctrl   click it when selecting it or when it's already selected any other way. If you select your objects in 3d viewport, the last selected will become active in normal circumstances so it will act as you expect if you select your objects in the 3d viewport.
Note that active object is also not changed in 3d viewport when selecting in certain ways. For example if you select one object and then  Shift   drag select others.


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How to make a cut out on objects created by modifiers?
I have an object (cube) replicated by modifiers. Now I want to cut out a dedicated other object (cylinder) from it using a boolean modifier (inspired by https://youtu.be/1aNnERnHRZg?feature=shared&t=109). Here is my attempt which shows no effect regarding the cutout. What am I missing here?

just hide your cylinder and  if this doesn't work try clicking "fast", if this still doesn't work, pls provide blend file

.. just to illustrate  Gordon's answer   : ..  https://imgur.com/a/HbyZrCH)

Is there a reason for the Geometry to Instances node? If not, just delete it:

I do not know why inside the custom node group the Duplicate Elements node is set to Instance (EDIT: turns out, it only works with instances the way it is expected - I never use this node), but if it is necessary to convert the geometry, plug a Realize Instances node afterwards or at least as a final node before the output, because the Boolean modifier only works with "real" geometry, not instances:

Beat me to it :) (Markus did show you the contents of the Multiplikator group, in his illustration?)

@RobinBetts Sure, didn't look close enough and was already editing my answer ;)

Realize Instances solved it for me. The Geometry to Instances was something from one of the gazillion Blender "Experts" on YouTube (if only Blender had documentation that would be useful instead of this reference manual that helps nobody to approach it). As a nonnative English speaker I do not understand whether I need the G2I and RI thing or not. At least it did not work for me. Could you please clarify / show if and how?


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Simultaneously constrain object to point in tracked footage and distance to another tracked point
I have a movie clip which I have set up a camera track for, as I would like to capture the camera's movement in my 3D scene. I also added three additional trackers. In the tracked video, these tracked points are all collinear along an object and should form a line. After selecting the trackers and clicking "Link Empty to Track," I have three empties that, when viewed through the camera, track the three points in the video perfectly. However their depth from the camera is not known and Blender appears to have set it to some constant.
I would like to reconstruct the position of the object (shown as the red line below) in 3D space given knowledge of the distance between the three tracked points in real life. I believe this should be possible and that there wouldn't be any unconstrained degrees of freedom.

I have tried adding a "Limit Distance" constraint between two of the empties, hoping to be able to get closer to a solution, but just this causes it to violate the "Follow Track" constraint they were created with. The empty I apply the limit distance constraint to moves towards the other empty, and is no longer correctly aligned with the point in the video when viewed through the camera. I was hoping both empties would have moved up directly towards the camera to settle at the set distance from one another.

If the limit distance constraint is not the correct way to approach this problem, what other ways could I find the line that intersects the shown blue rays (as closely as possible, since they may not be coplanar) while maintaining a specified distance between the (closest) intersections?

Did you do a proper 3D Track in the Motion tracking Tab of blender and added these three empties afterwards with constraints? What is your end goal with this scene? do you want to composit 3D Elements into real footage?

@Marius I did a proper 3D camera track, as in the camera does move in 3D space and can produce similar framing as the original footage using a 3D scan of the environment I took. I'm not sure how to properly 3D track an object in the way I intend (I know planes are supported), so these empties are driven by point tracks. I do eventually intend to composite onto the original footage.

Have a look at this Video https://www.youtube.com/watch?v=nLj7Ef8VtuA. This will give you an accurate 3D Track of your Camera. Then you place your objects in your scene. This should work for your process. I would recommend opening a new Project and doing it in there. Should you have already created Objects, you can import them into this new file via File -> Append -> (Your Blender File) -> (What you want to import (i always import collections)). Let me know if this helped :)

I actually would recommend this video https://www.youtube.com/watch?v=vB07Bws8bmY for your specific need. The other one i mentioned above is great for understanding the motion tracking Tab but not so great for the actual tracking part. You can add your own tracking points with the add button above the detect feature button. When you want to place the objects in the viewport, open the overlay menu (Top Right, two overlapping circles) and check the Motion Tracking Checkbox. When you select your camera you will be able to see all the tracking points in 3d Space

@Marius I did follow a tutorial like that originally and my 3D camera track is working fine. The problem is that my object is moving relative to the camera and the background. I did just try adding an object track like suggested in one of those videos, but it requires 8 points to solve, and I only really have 3 to work with. I suppose I could re-shoot the video and add some giant plane with tracking points attached to the moving object, but that would be quite obtrusive and it still seems like it should be possible with the information I already have.


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UV unwrapping doesn't use full UV Space, but roughly a quarter of it
This problem occurs rather often the last weeks to me. I'm using Blender 2.83.0 (can't move to a newer version because of a few add-ons I need to use frequently). But nevertheless importing the project for testing purposes into 2.90, the problem stays the same.
If I unwrap my model, Blender barely uses the full size of the UV space. I didn't find any solution for this problem.

Even if I use the UV Packmaster 2 Add-On, the UV Space doesn't look any better:

Blender generally scales the UV relative to the longest (fully self-connected) piece. To make it take the full space, add seams to the longest piece(s), to make it roughly the same "size" as the rest of the islands:
(Note - the places I have marked for seams are only general suggestions of where to put them - you will have to find and mark the edges that make the most sense for your object - just try to keep the islands roughly the same size as your other group of islands)


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Why is my mesh transparent in viewport shading?
So i'm a newbie, just started watching Blender Guru's "donut tutorial"
and i'm on part 6 level 1, when you try to render the thing that you've made.
i made a donut, and when i pressed "Viewport Shading"
my donut is gone..
This is the mesh i've made

And this is the mesh when i clicked "Viewport Shading

i can't find anything on the internet, or i just couldn't understand...

maybe you have an AMD graphic card, switch to previous driver, or in the Properties panel > Render > Performance, enable High Quality Normals

@moonboots ah yeah i have AMD graphic card.. Okay i'll try it out and came back if it fix the issue or not.. thanks!..

@moonboots okay the Render Properties > Performance > Check High Quality Normals is Working, thanks!


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Change image "Color Space" setting from script
I`m loading some images from script and I need to be able to change their "Color Space" setting from python. Some of the images are normal maps and it took me a while to get what was going on and how to fix that. Changing the parameter manually via Image Editor works, but I need to change it automatically.
Referring to doc: https://docs.blender.org/api/current/bpy.types.Image.html it seems that the name is "colorspace_settings", but appears to be read-only.
Does anybody know how I can change it? I tried browsing Blender source, but it`ll take me some time to find and understand how to do it.
Thanks for your time. :-)


text:
How can I colour / fill up an arc surface in 2D animation
I was using arc in draw mode to create a shape

For now, I only know how to fill up a flat surface, but not for when I make an arc surface like this one:


text:
Toon Shader appear to be have gray colour coming out, for the shadow
When I tried to make toon shading, with diffuse bsdf, shader to RGB, color ramp, and material outputs nodes, it appears to be fine if there is no object covering it with shadow(with only light emit and create the shadow)

(the light is near the floor)
but when there is something blocking the object and create a shadow depend on where the light, it will appear with some gradient

(the light is behind something, causing the floor to have gradient)

(my render properties)
all object have the same nodes, only diffuse, shader, color ramp, and material output.

Go into the Render Properties tab, and under Shadow, turn off (un-check) "Soft Shadows". Also, consider enabling high-bitdepth, and if the shadows have jagged edges, you can get rid of them by increasing the shadow-map Cube Size.


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Colour of iris doesn't show in render (cycles)
I followed a tutorial (https://www.youtube.com/watch?v=E0JyyWeptSA) on youtube for the procedural eyes of my sculpture. I used nodes to make them. When I render my sculpture, the colour of the iris doesn't show. However, when I render the eyes in the same file but outside of the head, the colour shows. I think it has something to do with the sclera and the way the light hits the eye. Maybe someone can help me with this problem.

https://blender.stackexchange.com/questions/41603/objects-behind-glass-appear-too-dark

thanks for the link! I tried to add the glass shader but it didn't change anything. The problem that the iris is grey/too dark only appears when I put the eye into its eye socket.


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A gray 'pyramid' appeared that limited my model to what was inside that 'pyramid', but only in solid and wireframe view
I was editing in material preview, but when I switched to solid view, most of my scene did not show, just the parts that fell into a dark rectangular pyramid.  The pyramid itself is positioned and rotated arbitrarily.

can we get a screenshot?

Could it be the view clipping. Press Alt B to disable view clipping.


text:
Installing Add ons
I have been trying to install the Building tools and the MB Labs add ons.  I have followed all instructions.  When I click to install them, they show up as having been installed.  But, when I hit "N" to bring them up in properties, they are not there.
Am I missing a step?  or have others had a similar problem.  If so, what is the solution?

Have you enabled them in Edit > Preferences > Add-ons (checkbox ticked in front of the add-on's name)?

Sometimes, addon after being installed and activated require Blender to be restarted.


text:
Why do my mesh planes get deleted when I bind all objects using control + j?
When I bind all objects the mesh planes get deleted, I’m trying to export it as one piece so any solutions?

please explain more and a picture can be good

Probably they get moved, not deleted. If so, before joining, select the disappearing objects and press Alt P "Clear and keep transform", then join with Ctrl J.


text:
Blender - Substance Painter Opacity Settings
I was only able to find one other question related to this, however it did not look like it got answered.
*If this question should be for a Substance Painter forum, please let me know!
I have several screenshots - one is from Substance Painter of a sphere with a blue-tinted opacity (as well as some other dirt/dust layers). When I bring it into Blender, It is very transparent and the color doesn't seem to match up. I have several screenshots of the node setups I've tried. In one of them it is very opaque. Let me know if there is an easy solution. I am new to using substance painter to export into blender.

You'd have to make sure that you're using the pbr metal rough template to export your textures. Then just plug them into one principled shader properly and make sure you're using the same hdri if you'd like to match the appearance. However, without seeing the actual files or any accurate description of what you're trying to do it's just guessing what you might missing here.

It looks like Substance Painter's internal renderer is using a built in HDRI.

You can see an environment reflected on the object.  You'd have to set up an HDRI environment in Blender to compare against.  There are lots of sites where you can pick up free ones.
You can implement one in your scene by switching your node viewer to World and using an image node set to Equirectangular, like this.

Or as of 2.93 there is an Environment Texture node.


text:
Irridescent Subtile Glass Shader
I would like to achieve such a result in Blender cycles
My goal is to reach a glass texture with slight touches of irridescence. I figured out how to make something purely irridescent or purely glass but I didnt manage to give the impression of a slight irridescent touch. As if the irridescence was only on some little parts of my texture.
So please, if you got any hints it would be of great help. Many thanks, stay safe.


text:
Eevee bad quality shadows near another face

So I am doing an architecture design for my art class and I decided to use Eevee to speed up the render time for the animation I was planning. However, I have some issues with the lighting here because there are shadows cast at different spots where they should not and on top of that they are in a pretty low quality.
I am using IrradianceVolume to make the interior lighting more realistic, if that is important. I also take use of contact shadows but as far as I know they are not the problem here.

Alright for anyone having same issues:
It was because of the IrradianceVolume Settings.
The Probes were to close to the walls and the Falloff was too high. That caused the weird shadows aka. the points were the light wasn't calculated anymore because of the high falloff.


text:
Blender crashed computer while baking cloth animation
So I'm following this Tutorial: https://www.youtube.com/watch?v=gFOJ7ul19AE&ab_channel=Ducky3D
I'm following exactly as the video, the only difference is that I'm using an Skull instead of the ball.  The animation is supposed to only be of 20 frames n the video at 2:50 he bakes the clothing animation, when I do that, the program bakes normally, but always, the bake stops suddenly, and the % of the baking wont go up, and the computer gets incredibly slow, bordering crash, (although it always goes kind of slow and stutters a lot)

that's the only picture i could get because the program crashed after only adjusting the pressure as seen in the video. hope you guy cqan help me out.
The specs are:
Graphics: Geforce RTX 3060ti
Ram: 16Gb
motherboard: MSI x571-A pro
Processor: AMD Ryzen 5 3600TX 6-core 3.8GHz
windows 64bits

With self collision and a complex object in the center, I can almost guarantee you're running out of RAM and your PC is having to do swap-file operations.
Check your Committed Memory (RAM + Virtual Memory) in Task Manager while doing a bake.

In the short term, you can reduce the number of divisions in the mesh or lower the quality steps.
In the medium term, I can suggest buying a VERY cheap SSD (that you do not care to ruin) and running your page file off of it for bakes.
If you plan on doing this for long I'm sure you'll find plenty of reasons to upgrade your hardware, you won't need any convincing from me.

Thank you!i just bought his computer LOL, but I will have it in mind, what do you think i should upgrade first? indeed  the RAM was at full 16GB, and the program was in the ssd, i'm not sure how to run the page file but i'll serch it

It looks like a fine computer.  I just looked it up and your board supports up to 128 gb of RAM, so I'd maybe look at a 64 gb kit.  It's tough for me to recommend stuff right now, though.  The market is weird.


text:
Deform mesh along another mesh without distortion
I'm trying to create a non-destructive piece of road with a curb attached. The road and curve are both controlled with a curve that works fine.
The problem occurs when I wanted to add a SimpleDeform to the road mesh to give me the ability to easily taper its width. What I want is for the curb mesh to stick to the side of the road but not get distorted. The closest I've come is using the Surface Deform modifier on the curb however, this creates bad distortion.
Hopefully, the image helps explain. The ultimate goal is to keep everything non-destructive so I could change the taper and the curb would follow along.
Let me know if you think this is possible. Thanks!

The image is not very clear, the resolution is too low. Are you trying to repeat a single block of "road" with an array over a curve with a curve modifier? And then are you trying to do the same with a single block of curb?
Where are the origins of those two base meshes?

If you only want a color difference then perhaps you can apply a texture.  Perhaps you can join the meshes into one and use two different materials.  Please tell the reader if you think the two ideas are useful. If the basis of your animation were to show vandals peeling off the curb then that would be more difficult.

So I have a road piece that has an Array modifier then a Simple Deform (set to taper)  and then a Curve modifier and the same on the curb mesh except for the Simple deform. The curve and array allow me to use a curve to define the length and bend but I also wanted to interactively change the taper of the road mesh and have the curb go along with it. If i make them the same mesh and add a taper then the curb mesh will distort which is not what I want. I want it to maintain its shape but still follow along the edge of the road when I use the Simple deform.

Simple Deform will give you slightly different results if the objects are not exactly the same. Not very good at deforming multiple objects and keeping them together as far as I know D:
Try this instead:

Select the first or last control point of the curve.
Scale the control point with ALT+S or through the N Panel.
Select ALL curve points and Right Click to bring up the Context Menu
Select Smooth Curve Radius.

Note that this aligns the curb way better, but it's still deformed. Everything you want is certainly possible, but doing it in a way that's 100% non-destructive and easy to modify and without deforming the curb width... all of that at the same time requires a not so simple setup or a more destructive approach unfortunately (or learning Houdini).

If you don't mind being more destructive, you can Shift+D to duplicate the edges of your road (you will have to apply your modifiers to create real geometry first). Then convert those edges to curves and use these new curves as paths for your curbs to follow.


text:
How do you import an image with a transparent background?
Seems basic and straight forward right?
Import a picture from a domain where you intentionally made the backgound transparent to find it with a clear white background once opened up in Blender.
My question: How... in 2.8, do you import a picture namely of LinArt with a transparent background or with, and then remove that background the picture most likely has been stuck onto once its opened in blender 2.8 to originally be left with literally just the lineart?

https://blender.stackexchange.com/questions/46424/add-a-transparent-image-on-top-of-a-material/46447#46447 https://blender.stackexchange.com/questions/6416/transparent-image-textures-in-cycles/6423#6423 https://blender.stackexchange.com/questions/1842/how-can-i-setup-a-material-in-cycles-for-z-transparency


text:
Having trouble making an indent using the Boolean modifier
I am very new to blender, and I was wondering if there was a way to fix this issue that I have been having. For my Gameboy model that I have been trying to make I need to create an indent where the button would extrude from. I found the the Boolean modifier would probably suit this task, but I am not sure how to simplify it or get rid of all of the pinching. Thanks in advance.

You can use boolean, but as you want to end up with only quads you should use less vertices so that it will be easier to correct the topology.
Here are 2 tries, one with a circle printed with Knife Project tool then correcting the topology with some vertices merge, additional edges, the other using W > LoopTools > Circle.


text:
Subsurface Scattering on a proxy object
I have an object that has a very fine geometry.

Now I would like to apply Subsurface Scattering, but since the object is made out of a lot of individual tubes, the Subsurface Scattering is not working as wanted. I assume, that the geometry is the reason for this.

The SS that I would like looks like this. I did this on a simpler geometry without the tubes.

Is it possible to sort of tell the shader: "Use SS but with a geometry from another object"
I would like to avoid doing it with the compositor and rendering twice.

Tubes are open or filled? If you enable Face Orientation overlay -Normals are orientated, correctly (blue)? Since correct SSS appearance is based on object shape you cant get it correct with different (proxy) shape ... and I don't think you can fake it other than composite way.

Instead of using the SSS from the proxy object on the highpoly object, why not bake the normals from the high poly object to the low and then render the low poly object with its own SSS?


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How to rig a Seatbelt? (Buckle passing through seatbelt)
I am having some trouble with rigging a seatbelt. I want to create a rig where the seatbelt reacts to the movement of the seatbelt buckle. As the buckle would move (Up and down for example), the seatbelt should move with it and pass through the buckle attribute accordingly.
I really couldn't find any info on especially objects/rigs sliding or passing eachother.
See blend. file which I included.
https://pasteall.org/blend/246862150d814f40b4509414c372ff1a
Thank you so much in advance!
Cheers,
Sander

You could do it with Lattice:

Bring back your belt to a flat plane:

Create a lattice,  in the Properties panel > Object Data choose its Resolution (here 2/1/5), in Object mode, scale it down, rotate it so that it frames the area that you need to tweak. Give your belt a Lattice modifier and choose the lattice as Object.

In Edit mode, move the vertices of the lattice so that it tweaks the belt the way you want. Parent the lattice to the buckle so that when you'll move the buckle, the lattice will follow and tweak the belt:


text:
Why does rotating one control point, affect the tilt of other control points of a bezier curve?
I am using a bezier curve to rig something. However when I rotate a singular or more control point by using an empty (Curve is hooked), other control point tilt (rotate, only tilt) with it . Furthermore, control points downwards the point I do want to rotate are unaffected whereas controlpoint upwards are affected.
How is this possible? And is there a way to prevent this?
I've included the blend. file here:
https://pasteall.org/blend/ac49ce2d8f13412dbe06429dfc82d465
Many thanks in advance!
Sander
-


text:
Is there a way to edit the new object menu in blender 2.83.5?
I've been enjoying the new features and stability of blender 2.83.5, however I discovered an issue. Normally when you create a new object in your scene a menu appears to offer options on the object. I am getting this menu however it is entirely grayed out and uneditable. If anyone knows something about the new version having either a bug or new way of working I'd be very appreciative of any info.

it may be because Global Undo is deactivate in the Preferences > System > Memory & Limits

I wouldn't have thought of that. Yeah that was the issue, thanks!

nobody can guess   ;)   I don't even know why Global Undo does that


text:
How to ask Blender to return an angle of a tangent in a driver?
My vehicle is driving along it’s locale Y-axis. When it encounters a hill the empty on the front lifts up and creates an angle with the empty at the rear.  How can I ask Blender to return the angle in a driver math expression for the vehicle to rotate on its X-axis. See image.
The Y is known as a fixed construction value of the verhicle (6 meter)
Z = ( z-location Empty Front) – (z-location Empty Rear)
To calculate the tangent in the driver :
Var_1 = z-location Empty Front
Var_2 = z-location Empty Rear
Expression for tangent : (Var_1 – Var_2) / 6
So I have the tangent, how do I get the angle ?
I tryed this : arctan((var_1-var_2)/6), but Blender sais ERROR : invalid Python expression

Consider a track to constraint. eg track the axis empty to the other, giving it the rotation required.

For a ‘Track to’ constraint I have to use bones, it doesn’t work that well with empties I did the test. It is a decision I have to make ; bones or empties. I just started rigging my vehicle, still have to do the tracks. Don’t know yet were I will end. It doesn’t matter fooling around, testing out ideas and learning in the process. Thank you for pointing that out to me.

The python function is atan() not arctan(), and generally its better to use atan2(y, x) instead of atan(y/x) because the former won't generate division by zero.
Also note you have the hypotense so you want asin(var_1-var_2)/6) to get $\alpha$ since you haven't actually found Y. See https://docs.blender.org/manual/en/latest/animation/drivers/drivers_panel.html#simple-expressions

atan((var_1-var_2)/6) and asin((var_1-var_2)/6) work perfectly.
I must do something wrong with atan2((var_1-var_2)/6) Blender gives the error ‘Invalid Python expression’
Thank you very much for helping me out :-))

atan2((var_1-var_2), 6) with two arguments, but again, this is incorrect because 6 is the hypotenuse not what you have labeled 'Y'.

atan((var_1-var_2)/6) and asin((var_1-var_2)/6) works perfectly.
Here is a little video, my first start to animate  my tracked lander on shore (WIP): www.dolores74.com/blender/tangent.mp4
Thank you very much for helping me out :-))

Say thank you by upvoting and accepting the answer. Nice job of the video!


text:
merge of vertices not working
When I select a couple vertices, open the context menu, and try to "Merge Vertices", it doesn't do anything.  The vertices stay exactly where they are like no action was performed.  What am I doing wrong?

are the 2 vertices inside the same object or have you selected 2 objects?

two different objects I'm trying to join together

yeah, answered my own question there I guess.  I merged them together and now the merge vertices works.  Thanks for the hint.


text:
Understanding what "dependency cycle" means, why it happens, and if it is a cause of concern [MWE provided with cloth]
I am using Blender 2.82a. My code seems to be working but creates "Dependency Cycle" messages from the command line, so I hope to understand why they are happening and if they are a cause of concern.
My particular use case is dropping a ball into a bag, where both the ball and bag (implemented as a half-sphere) have the cloth and collision modifiers, based on one of my answers here, but the use case is less important to me than understanding what causes dependency cycles. Here's what Blender looks like after running my Minimal Working Example:

Here is the Minimal Working Example script I am running:
import bpy

def clear_scene():
    """Clear existing objects in scene."""
    for block in bpy.data.meshes:
        if block.users == 0:
            bpy.data.meshes.remove(block)
    bpy.ops.object.mode_set(mode='OBJECT')
    bpy.ops.object.select_all(action='SELECT')
    bpy.ops.object.delete()

def make_plane():
    """Underlying plane. Use collision to support the fabrics."""
    bpy.ops.mesh.primitive_plane_add(location=(0, 0, 0))
    bpy.ops.transform.resize(value=(6.0, 6.0, 6.0))
    bpy.ops.object.modifier_add(type='COLLISION')

def make_object():
    """Make an object that goes inside the bag.

    We may only need the cloth modifier (collision might not be needed). Make
    sure the pressure is high to avoid the cloth 'ball' from collapsing.
    """
    bpy.ops.mesh.primitive_uv_sphere_add(radius=0.3, location=(0, 0, 2))
    bpy.ops.object.modifier_add(type='CLOTH')
    bpy.ops.object.modifier_add(type='COLLISION')
    bpy.context.object.modifiers["Cloth"].settings.quality = 10
    bpy.context.object.modifiers["Cloth"].collision_settings.collision_quality = 5
    bpy.context.object.modifiers["Cloth"].settings.use_pressure = True
    bpy.context.object.modifiers["Cloth"].settings.uniform_pressure_force = 10

def make_bag(radius=0.8, x=0.0, y=0.0, z=2.0, z_thresh=0.0):
    """We still use the cloth modifier, but the actual mesh is a UV sphere.

    Make the mesh at height z=2.0, then for any vertices with z values are
    *above* z_thresh, we delete. NOTE: it's actually local, so getting z
    coordinates of the sphere will still be 'centered' at 0. Also, adding
    collision modifier so that it can act as a 'bag' and support items.
    """
    bpy.ops.mesh.primitive_uv_sphere_add(radius=radius, location=(x, y, z))

    # Delete vertices that are ABOVE z_thresh.
    bpy.ops.object.mode_set(mode="EDIT")        # Activating Edit mode
    bpy.ops.mesh.select_all(action="DESELECT")  # Deselecting all
    bpy.ops.object.mode_set(mode="OBJECT")      # Going back to Object mode
    vert = bpy.context.object.data.vertices
    for v in vert:
        if v.co[2] >= z_thresh:
            v.select = True
    bpy.ops.object.mode_set(mode='EDIT')
    bpy.ops.mesh.delete(type='VERT')
    bpy.ops.object.mode_set(mode='OBJECT')

    # Add some cloth-related modifiers.
    bpy.ops.object.modifier_add(type='CLOTH')
    bpy.ops.object.modifier_add(type='COLLISION')
    bpy.context.object.modifiers["Cloth"].settings.quality = 10
    bpy.context.object.modifiers["Cloth"].collision_settings.collision_quality = 5
    bpy.context.object.modifiers["Cloth"].collision_settings.use_self_collision = True

if __name__ == '__main__':
    clear_scene()
    make_plane()
    # BOTH of the following lines must be un-commented to create dependency cycles.
    make_object()
    make_bag(radius=0.8, x=0.0, z=0.9, z_thresh=0.40)

If this is in a file called test-dependency.py then running blender -P test-dependency.py will produce the following:
$ blender -P test-dependency.py
Read prefs: /Users/anon/Library/Application Support/Blender/2.82/config/userpref.blend
found bundled python: /Applications/Blender.app/Contents/Resources/2.82/python
Warning: property 'release_confirm' not found in keymap item 'OperatorProperties'
Info: Deleted 3 object(s)
Dependency cycle detected:
  OBSphere.001/Geometry Component/GEOMETRY_EVAL() depends on
  OBSphere/Geometry Component/GEOMETRY_EVAL() via 'Cloth Collision'
  OBSphere.001/Geometry Component/GEOMETRY_EVAL() via 'Cloth Collision'
Dependency cycle detected:
  OBSphere.001/PointCache Component/POINT_CACHE_RESET() depends on
  OBSphere/Geometry Component/GEOMETRY_EVAL() via 'Point Cache'
  OBSphere.001/Geometry Component/GEOMETRY_EVAL() via 'Cloth Collision'
  OBSphere.001/PointCache Component/POINT_CACHE_RESET() via 'Point Cache -> Geometry'
Detected 2 dependency cycles

Both of the objects must be created for the dependency cycle to be created. Creating just the ball, or just the "sack", will not result in dependency cycles, interestingly. I am not sure why.
I am curious why these messages appear and if they are harmful. I'm having difficulty figuring this out based on various references. These are what Google shows me when I search for dependency cycles in Blender:

These questions: (question one, question two, question three) deal with dependency cycles with armatures. I am not using any armatures here and am not sure how to use insights from the answers there.
This question might be more relevant but doesn't have much information (and no answer).
This blog post looks like it might be useful for a high-level overview on dependencies, but is from 2014 (might be outdated) and again uses armatures.
There's a post from Blender Artists but looks even older (from 2009), and seems to suggest the warnings are important.
This Wiki reference perhaps provides the most comprehensive overview. It starts with saying that "The main goal of dependency graph is to make sure scene data is properly updated after any change in the most efficient way" ... so does that imply that it's an efficiency issue? If so then I'm probably fine with dependency cycles, since I have powerful machines that I can use.

Thanks for any feedback you may provide.

Seems like a limitation of the cloth simulation implementation T69727 that doesn't allow cloth with cloth collisions. I'm not familiar with that particular area of code to give a definitive answer on the spot though.

That basically means : A is determined by B and B is determined by A, so the system can't be solved. For your particular use case, I don't know ; but it's a common problem with bone constraints and leads to unpredictable, "quirky" animations.

I see, thanks @RobertGützkow and thibsert. From visually inspecting my animations, I don't currently see any weird physics. But it's hard to say. Perhaps it's harmless but could lead to weird animations that I just have to watch out for?

When I see Dependency cycle detected Blender starts to behave non-deterministic. It seems that actions that I do will be executed up to the point of dependency cycle and the rest of the action is silently ignored. This results in different glitches that look like major rendering errors. I think it may also cause corrupted .blend files but I'm not sure about that.

In practice, having a dependency cycle means that Blender's internal evaluation order will matter and values may take a couple frames to converge on a valid solution, or diverge altogether.
E.G. If A=B+1 and B=A/2, then you have a dependency cycle of A—>B—>A.
If you start with A=4,B=4, then after one frame you could have either A=5,B=2.5 or B=2,A=3, depending on whether A or B gets evaluated first.
Usually it will eventually converge on a valid solution, like A=2,B=1, but some cases will diverge altogether.
Animated values will generally always lag behind by a couple of frames, because the values can only be evaluated using their results on the last frame.
For physics sims, I tentatively assume dependency cycles will be smoothed out by the solver iterations unless I can see a visible problem.

Explanation:
Having a dependency cycle means that somewhere in the Blender file is a circular sequence of values that all require each other to be calculated first, with no end, so there is a "Catch-22" in that there is no valid starting point for figuring out any of the values in the cycle.
A normal (non-circular) scene may go something like this:
Object1.location = Object2.location

Object2.location = Object3.location + 1

Object3.location = 5

In this example, because everything ultimately depends on Object3.location, there is a valid order in which the dependency graph can be traversed and the scene can be calculated. You can start with Object3.location, from that you figure out Object2.location, and from that you can figure out Object.location.
Once you step through and calculate all the steps of a non-cyclical dependency graph, all values will match their definitions.
But what happens if you have cyclical dependencies?
Object1.location = Object2.location + 1
OBject2.location = Object1.location - 3

In this example, because the two objects circularly depend on each other, there is no valid way to calculate the values in question and be sure they match how they're defined. You need to know Object2.location in order to figure out Object1.location, but you need to already know Object1.location in order to figure out Object2.location, so you're screwed, basically.
Under conditions like this, Blender will still try to figure out the required values by plugging in the last known values for their dependencies (usually from the previous frame). But it cannot guarantee that the results will be consistent with how the values are defined. In fact, in some cases like the above example, there may not be a consistent solution (or at least not one that can be found through naïve iteration).

Other MWEs:
You don't actually need to set up a physics sim for a MWE of a scene with a dependency cycle. IMO, the easiest way to create a dependency cycle is to just have two objects with constraints (or modifiers) that point towards each other. In this case, the transformation of the first object depends on the second object, but the second object depends on the first, so there is no valid starting point for calculating the scene. (Depending on the type of constraint, you may even be able to see the latency introduced by Blender's using  values from the previous frame when you move one of the objects around.)
Or for an example that's easier to play with and dissect, you could also set up two drivers that both use the evaluated values from each other.

Will Chen's answer has some detailed info that I'm not going to repeat (on why a dependency cycle happens, what it means), but I think there are some remaining questions you have that I'll do my best to answer.
I'm also going to call dependency cycles "loops", because that's what they are: loops in controls.  And because I think it makes it easier to think about them when using a plainer name, something less technical-sounding.
While it is possible to have loops-- Blender won't just error out on you-- it is almost never wise.  It will make it irritating to animate anything.  And you will probably end up with render/preview disagreement, which is maybe the worst thing in the world for a rendering engine where each frame could take hours to render.
However, that's talking about the general case of these dependency cycles, which are a lot more likely to come about via rigging or something.  You've got a very specific kind of loop: a physics-collision loop.  This is basically unavoidable when combining collision and physics (presumably, collision to affect other physical objects, which makes that loop clear: clothA depends on clothB which depends on clothA.)
Physics-collision loops have historically been okay, and have been used by a lot of Blender users to create interactions between physical objects.  Physics create render/preview disagreement all on their own, until you bake physics-- at which point the loops disappear anyways.  And if you're running physics, you're very specifically not hand animating stuff, so there's no difficulty in controlling the animation.  They may even act at a higher frame rate (the physics subframe), thus "evening out" their dependency problems.  I'm not sure; I haven't delved into the code or anything, and questions I've asked on devtalk regarding this particular problem have gone unanswered.


text:
no point, segment, face selection options in edit mode after svg import
I should preface this by admitting I'm a complete Blender noob.  I have no problem creating basic objects and extruding faces in edit mode.  However, as soon as I import an svg that I want to extrude the faces on my interface completely changes and I no long have the option to select points, segments, and faces to extrude.  (Dis)enabling overlays doesn't seem to make a difference.  What am I missing here?

SVG are not meshes, they are curves (vectorial), so you won't have the same options as for meshes. To convert a curve to a mesh, select the SVG in Object mode and go in the Object menu (horizontal menu bar) > Convert To > Mesh From Curve

don't convert to mesh to extrude, use the extrude in the geometry of the text object https://blender.stackexchange.com/questions/170441/how-do-i-scale-text-on-the-z-axis/170444#170444


text:
vertices run wild during bevel
As near as I can tell, there is only one vertex in this corner, but when I try to bevel the edge it seems to let go and run wild.  What can I do to make it stay put during the bevel?

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

You have overlapping vertices and edges in your example.
The easiest way to fix this would be to select every vertex in your mesh, press m, and then select merge by distance.

Thanks for the suggestion.  I was able to get rid of 4 vertices doing that.  I kept increasing the distance until it started messing everything up.  Unfortunately, the bevel still has this behavior.

If you upload your .blend I (or others) can definitely figure this out for you.

Here's the blend https://drive.google.com/file/d/1NsYejv7-pvo9Ek07T7C31y_vxvfm12Ag/view?usp=sharing

I used the Construction Lines add-on to create the lettering.  My attempts to import an SVG from Inkscape were too messy.  My goal here is to round/bevel the edges about 0.05m and apply a rock texture look using a rock brush and texturing technique I was watching here https://www.youtube.com/watch?v=w8dZl8uheKA&t=659s
When finished, I want to save it as a Collada and import it into Second Life.


text:
What easiest way to animate rigged 3d model of person?
folks!
I'm alone creating a fitness app for mobile devices. And I need animated examples with workout exercises.
I bought rigged 3d models. But the problem is that I can't hire professional animators.
Doing animations by hands it's too long for me as an inexperienced at 3d animation guy.
Can I do animations with motion capturing with my iPhone and markers on different parts of the body? Or any similar way.

That's a question for the game engine you're using. Transfering data from iPhone to Blender will be a pain, and not just because it's Apple.

Motion capture devices require multiple cameras because more than 75% of the markers have to be recorded to have meaningful data. After motion captures are done, it's still not functional ... you still have to do manual motion cleanup for the captured data when some data are not recorded properly. So in short you are better off buying cleaned up motion data or hiring an animator for the job. There is a lot of work after buying motion data ... you need to know how to make sure the scale of the motion data fits the model ... and fix them, you will need a technical know how.


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How to edit a shapekeys lerp?
Made a shape key to make my character get taller, it has a negative value (so they can be shorter as well). The animations look fine when the shape key causes the body to get taller but not when they get shorter.
I just need to move a couple verts on the -1 value on the shape key but If I go into edit mode it only allows me to edit the +1.
Is there a way to edit the -1 shape key's verticals? I just need my armature bone to be at the correct level for the dudes elbow when it gets shorter.
This is a dupe question cause the first time it went unanswered

Did you ask this question a few days ago and delete it?

I literally said this above: This is a dupe question cause the first time it went unanswered

Sorry, I missed that. In that case, please don't do that again. There are several things you can do when no one answers, but deleting and re-asking should not be one of them. See: https://meta.stackexchange.com/questions/289858/user-deleted-question-with-my-answer-then-asked-question-again

If you don't got rep to get a bounty and I can't figure out how to fix it the question will get re-asked. That's just how it works.

I recommend not doing that. As noted on another StackExchange site, this behaviour may eventually lead to your suspension: https://math.meta.stackexchange.com/a/23042

I am literally incapable of caring

Shape keys, Relative or Absolute, may only be edited at 1. That is their fixed point of reference. In the case of Relative shape keys, what is stored is the difference between that fixed point of reference and whatever is in the 'Relative To' field of the key.
Relative interpolations are linear. Setting a value outside 0-1 is calling for a linear extrapolation, beyond 0-1, of the imaginary straight lines in object space down which vertices travel between value 0 and value 1.

Using 'New Shape from Mix' in the menu under the little down chevron on the right of the keys list, you can take your -1 extrapolation of the 'Tall' shape key and make it into a key in its own right; say.. 'Short'.
You can now edit the Short key.
How you deal with the keys after that is up to you.. if you want to return to just 2 keys, you could, for instance, delete the Basis, and have a single relative key from 0=Tall to 1=Short, but beware, the whole journey (the new straight line) will not pass through what was 'Basis'before.
You may go for Absolute keys, perhaps re-ordering them. In that case 'Tall', 'Basis'and 'Short' will be put in a single continuum, and you will have to alter only one 'Evaluation Time' value to pass through all three reference shapes, (with a choice of interpolation methods)

Thank you! That's exactly what I needed.