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How to straight loop cut? How to slide vertices straight align with target vertex?
i have 2 questions that really bothering me all the time. First is, how do I make straight loop cut based on the image below in red line. 2 lines which is not straight and not in same angle each other. The second question is i want to move slide along the edge, just want to make my orange line straight align with my blue dot vertex. Again, 2 lines which is not straight and not in same angle for each other. Actually I can do it easily in max but I want to improve my blender skill so I can leave this expensive software. Humble thank you for your help.

As I understand from your description, you use loop cut tool from toolbar:

So then you press to make a cut, not release mouse button, instead move cursor to the sides, and you will see that you are able to slide loop cut to the sides. Release button only then you like the position of the cut.
If you press E while holding the mouse button, you will see that the loop cut is parallel to one side. If that side is wrong, press  F to flip the side.

Also, you can use knife tool which give more freedom in making cuts.

If you press A after adding the first point, you will be able to make perfect horizontal or vertical cuts.

Information about available keys you can see in the toolbar:

hi thank you for you quick reply but from your image, you have both top and bottom face in straight each other. but in my case both face top and bottom part has different angle. i already tried this press e and f button before but still cant get what i want which is straight. thank you.

It can be parallel to one side, if both sides tilted, you will not get perfect angle. In this case, you can use knife tool (see updated answer)


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Importing a CATIA 3D Model file (*.model) into Blender
I'm hitting a brick wall trying to import a *.model file into Blender.
The kind of model I tried to import is a file with the .model file extension. It's a kind of CAD model, CATIA 3D according to the fileinfo.com site. Blender's import feature doesn't cover this model type. I don't have access to any CAD software myself. Otherwise, I'd save it as a .stl file and move on. Haven't been able to find a reliable way of converting a .model file either. I'm at a loss.
Is there an easy way to do this?

Hello and welcome! If you want a satisfactory answer, you need to give us more details. What kind of model did you try to import? What have you tried? What went wrong? The normal way to import a file is to use the menu File > Import > ...

The kind of model I tried to import is a .model file. It's a kind of CAD model. Blender's import feature doesn't cover this model type. I don't have access to any CAD software myself. Otherwise I'd save it as an .stl file and move on. Haven't been able to find a reliable way of converting a .model file either. I'm at a loss.

That doesn’t sound like a standard format. What program created it?

@TheLabCat https://fileinfo.com/extension/model

yes, looks like Catia v4 (https://www.okino.com/conv/imp_catia5.htm) and (https://youtu.be/ra9bdt1uEFI). Have you tried this Okino PolyTrans demo?

I did. My antivirus kept flagging it during the installation. Spooked me a bit so I gave up and kept looking. Maybe I'll have to go back and try it?

uh. If you're worried you can install it in a VirtualBox or VM. It's officially recommended for Mac users (because it requires Windows). Windows requires a license to activate it. But you can use it for 30 days without activation.

source: Stack Exchange

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

sort: votes


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Need help setting up lighting for a render like this
If anybody can help me with lighting and settings to get something like this image

Thanks

Welcome to Blender.SE, Could you specify what render engine you are using? Looks like it could works with a single light source (maybe two...) rightly placed over the subject. What's going wrong? Could you show a picture of your best result? It would be easier to guide you from there.

Basic setup
First, make the world background black, then add a single light because in your image there is no light whatsoever in the shadows.
Position/Orientation
The position of the light will depend on the type you will use, e.g., for a sun lamp the position doesn't matter. Approximate orientation can be determined by examining the shadows and highlights on the chin and hair regions. See in this picture how the shadow around the chin (relatively smoothly curving surface) is left of the center of his chin and the highlights in his hair extend to the right of the midline through his face.

Example 1
In this case, I used a single area lamp with a size of 1. You can see that with the more finely detailed model due to texturing, the lighting looks better than in the next example because of the finer shadows.

Example 2
In this case, I used a sun lamp, but of course, you could also use a spot, point, area, or even a mesh light.

Extras

You can adjust the lamp size to change the how blurred or scattered the shadows are.
If you want any ambient light to show on your object (which is not in your picture), you can change the strength of the world background based on if a ray is coming from the camera.

If you want more photorealistic light behavior, get Filmic.

The models that I showed in the demos are available on Blend Swap here and here. You can download the rendering setup for the skull project that I edited here:

Keeping in mind that light travels in a straight line. If you study the shadows there are clues as to how to recreate the lighting.
In the reference image the shadows are black = One light source. The angle of the shadows reveal the light is slightly up and to the back of the subject. The shadow edges are hard which means the light source is either a spot light or small.
EDIT: A little more on light source relative to shadows.There are two major factors in the light source that effect the resulting shadow. It's size and distance from the subject. Light sources that are smaller and/or further away yield a shadow with a "harder" edge. Conversely, light sources that are larger and/or closer to the subject yield "softer" shadow edges.

If you feel Its solved please mark my early answer as solved... smiles

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

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


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How would you do this cloth sim? I'm having trouble with the cloth not wiggling around after landing on the floor/cube base
Here's what I've done:
https://drive.google.com/file/d/19vFh_NQxiJjMe6FzXpE3i3mPnR-lzdJO/view?usp=sharing

How can I get it to fall with more natural weight and speed but also not move once hitting the ground?

I believe cloth objects are not meant to be solidified like that, so you may want to turn all the parameters down by half or something. Other than that, I think you should set the change endpoint  to have the simulation stop once it’s all fallen onto the ground.

if you want the cloth animation to be quicker/slower, just use the speed multiplier to get this effect.

Here as an example speed multiplier of 2:

If you don't want it move at the ground, just stop your animation earlier ;)
Here is your "old" cloth sim on the right, mine is on the left.

The big problem with your "more natural" is, that this word is very subjective. Everybody has another opinion about what is "natural".
Here are my cloth settings, if you are interested:

The main values i changed, were:

speed multiplier (to speed the simulation up)
friction (to have another look and make it stop earlier)
stiffness and damping to make if more stiff ;)


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I need some help in making this cloth simulation more realistic
I'm doing a cloth sim, where I have a plane acting as a backdrop, then falling like a curtain and revealing the true back plate. How could I make the curtain drop more realistic?

https://drive.google.com/file/d/19vFh_NQxiJjMe6FzXpE3i3mPnR-lzdJO/view?usp=sharing

Hello and welcome. While files, images, and external videos or links may be helpful additions they should not be the only way to obtain information about your issue. Don't make understanding your question rely on downloading a file, watching a video or visiting an external site. Use the builtin tools to upload images or gifs, along with thoroughly explaining the problem in written form so it can be indexed and searched for thus helping future visitors with similar issues.

Your curtains look a bit stiff and sluggish. With a few tweaks, it could look like this: https://i.sstatic.net/an5K1.gif  Is this "more realistic"?

@Blunder yes in terms of speed and correct looking fold, but it seems to move around a bit longer than a curtain would after falling. any idea how to control that?

Hello and welcome. Please don't post the same question more than once. If your previous question was put on hold, address raised the issues by editing it so it can be reopened rather than post a new one, otherwise see What should I do if no one answers my question?

One thing to check is the scale of your curtain. The physics engine takes size into account so it may look a little 'off' if your curtain isn't the size you're imagining it to be.
If all else fails (including changing the cloth properties as mentioned in the comments), you could try a neat little hack with Blender's time remapping feature: https://youtu.be/lxUBsZEfJNs?t=25
The same physics sim sped up makes it look heavier, slowed down makes it look lighter.
In the comments I see you mention that you're worried about how much the curtain moves around after it finishes its fall.
In the cache settings, you can choose the frame range for the simulation. The last frame you set is the last frame it'll calculate the simulation for. Basically, you can tell it when to stop physics'ing! Play your animation and find a point where it basically stops moving, and make that your last frame in the cache. When you bake the physics, it'll stop at that frame. This may look jarring if there was too much movement at the time, but depending on the animation and the camera angles, the viewer may not be able to see the curtain very much.


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Make an "auto switch" input?
Here is my problem:
I have a simulation system that creates a flow of points with the help of a Distribute Points on Faces node and the points are moving up with a Set Position Z offset.
By default, the Distribute Points on Faces node spawns points every frame making a constant stream of points going up.
What I'm trying to achieve is to have a switch linked to the input so the user could check the switch to ON and then have the system uncheck the switch back to OFF state exactly one frame later.
I know the user could keyframe the checkbox of the switch from OFF to ON and OFF again but I'm trying to make something automatic that would be triggered by the user and one frame later automatically switch it back again, so the user could easily spawn a single point multiple times with a single keyframe.
How could I achieve this?
Image 1: My current system
Image 2: Result if the switch is checked ON
Image 3: Intended result made artificially by keyframing the switch OFF-ON-OFF

i think this should be possible by a python script driver for the switch.

This would not be optimal in my situation. but yes it would be possible.
but i think it would also be possible if i manage to find a way to change the state of the "true" and "false" of the switch, if the switch toggle between a 0 and a 1 and each of theses are flickering from 0-1 each frame the toggle would have a similar effect, but i can't figure out how to do it...

i cannot think of another way toggle an input switch...


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Rigify tail can only moves in up and down direction
So I made a human meta rig, then adding a tail by using Rigify samples section. I made sure that I connect the tail to the spine to keep offset, and then made sure the rig type as spines.basic_tail as shown here. However, by using the IK control of the tail, I can only move it in up and down direction, and won't respond to sideways direction. How do I fix this?

In the Rigify Type panel, shift click on all three axis, then re-generate the rig.

Thanks for the answer!


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Export materials / texture from unreal 5.2 to Blender 3.6
I've exported some characters from Twinmotion, then into Unreal. I now need to export them into Blender.
I need help understanding how to apply the textures in Blender. They export in PNG format, and I've added the Basecolour and Normal which seems OK. My question is how to apply the other files.
Thanks for any help suggestions

https://blender.stackexchange.com/a/174461/19307

I think the overall setup in Blender would look like this :
 RMB > Open image in new tab to see it enlarged

I will go through each element using the names in your first screenshots for clarity
ColorMap

As you understood already, this one it plugged in the Base Color socket. This is the only node whose color management is "sRGB". All the other nodes must use "Non-Color".
MaskMap

Considering the name, and it being followed by different "tint"  colors, I assume this one is three color masks in each RGB channel, meant to tint the base color at your wish.
In my setup, I featured only using the G channel's mask. Use the Separate RGB node to pick any mask you want, add a Mix Color map, put the base color in socket A, the mask in socket Factor, and the tint color you want in socket B. I set it up only for the G mask, but you can add the other masks with two other Mix nodes as well ; all you have to do is add two more mix nodes, plug the mask in the factor and plug the previous mix node's output to A.
TangentMap

Uses the "F" map. It looks like it covers a different part of the mesh (either via a different material assignation or more likely a different UV map?) and is plugged as TangentMap in the hair material settings, and it has nothing in its B channel, so perhaps its R and G channels are used for hair's anisotropy.
Hence, I used a UV Map node to select a different UV made for the hair that you probably already have, used a Separate Color to plug the two R and G channels in the anisotropic weight and rotation.
MetalRoughnessOccMap

As its name indicates, it's three maps in one, each in a different RGB channel: Metallic, Roughness, and Occlusion (aka Ambient Occlusion or AO).
Use a Separate Color to isolate the channels, and plug R and G in Metallic and Roughness, respectively. AO needs to be Multiplied to the BaseColor data stream using a Mix Color node.
Normal

As you guessed, it's the normal map. Plug it in a Normal Map node and then in the Principled BSDF's Normal.

thanks for taking the time, I'll work through it and post the end results.

Hi L0Lock, I added a mix color map like you said for the other masks so i now have RGB separated and mixed with the Basecolor connected to A on the MIX node. Im just struggling on where to put the result from each mix into the Multiply Node as it only excepts one connection. (you can probably tell Im new to this) I could send you a screenshot if thats easier- I cant work out how to do that either :-(  thanks again for your help

If you want to add all the tint masks, all you have to do is add two more mix nodes, plug the mask in the factor and plug the previous mix node's output to A.

This worked - thanks again :-)


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Animating judo throws and working with two animations at the same time?
I'm trying to make a shared animation between two characters, and I am not sure about how to do it correctly. When I mean shared I mean that both characters interact in the animation, not that the animation is used by various characters.
I wanna make a Judo throw, in which case I figured after reading some tutorials that the best approach would be to make two animations, Throw01Caster (the player throwing people off) and Throw01Target (and the target being thrown off).
This is the gif of the throw I wanna make (not with the follow up to the ground, just the throw)

I tried to put an animation with two sets of skeletons to animate, but when I try to animate one the other just stays in rest pose all the time.
Considering the nature of the movement I'm gonna need to work with two bodies being visible all the time in order to avoid constant clipping.
What would be the most efficient way to do this? or is there any way to make both animations at the same time and then separate them? I'm open to suggestions.

This doesn't seem normal. Make sure both your armature are set in Pose Position.

That way, you should be able to animate one armature while the other play it's own animation.
If it doesn't, maybe provide your .blend file so we can dig deeper and faster.


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Find Bmesh face, given mesh polygon
Blender's OBJ exporter has a main loop that iterates over object mesh polygons, rather than using Bmesh.
I have added a customer integer data layer to an object's Bmesh and now want to access it during OBJ export, at the point where I have a mesh polygon. Can I use some index of the polygon to look up the Bmesh face?
This would also work if the face ordering within mesh and Bmesh are identical. But I've not read anything indicating this.
From what I've read, you can't access custom data layers via the old mesh API but if this is possible, that would be a satisfactory alternative.

Based on my experience, bpy_types.mesh.polygons and BMesh.faces have the same ordering. I wouldn't expect this to be noted anywhere in the docs, because the docs aren't perfect and often an attribute's description is something that could be (maybe actually was?) derived automatically from its name…
As for the data layer in bmesh… You probably can access it within the Mesh, as the data between the two is converted when switching between Object and Edit modes. If you reproduced your problem in a simple example, I could try to show some code how to do it specifically.

I'll test out based on direct array index access to confirm same ordering, as this will be efficient, given OBJ exporter already generates a Bmesh in order to triangulate. I'll post back on results and accept answer if it works. Cheers


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How to keep the 3D view consistent between Layout and Sculpt tabs?
How to stop Blender refocusing the view after switching tabs?
There are some tabs at the top of the window: Layout, Modeling, Sculpting, UV Editing etc. When I'm in Layout tab and click Sculpting tab, the 3D view window viewing angle changes. This is how the default behavior looks right now:

I would like it to look like this - stop changing the viewing angle and stay consistent between tab changes:


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Boolean Operator does not work correctly for animation
I want to do a boolean operation (Intersect) between a disk and a plane, to get the profile of the disk.
My disk is turning slowly by animation. For each frame I need the profile, to do some stuff with a python script.
The problem is, that there are some frames where the boolean doesnt work as espected. But in many frames it works. For example:

Frame 149 works (Profile is cut)
Frame 150/151 doesnt work (Profile is cut, but the cutting plane is still there - like merge)
Frame 152-154 doesnt work (No profile or plane is visible)
Frame 155 works

My animation only controls the rotation of the disk. I cannot see any system of working-not-working frames.
To solve the problem I read the following post: The Boolean modifier is not working
and do this

remesh the disk (from large triangles to the fine mesh you see in the file)
check normals (all were correct)
remove doubles (14 were removed)

Sadly these "Bugfixes" doesnt work. What can I do to get a proper profile in each frame? What am I missing?
This is a simplified .blend File (EDIT: Now with Camera):

Thanks for your reply!
CeDoMain
EDIT:

I'm using Blender 2.93.8.
I added a Camera to the file to show the profile.
I can see the wrong frames in Cycles, Luxcore and also in the Viewport directly. I provide some pictures how some of the described frames look to me:
Frame 149 with disk shown
Frame 149 with disk hidden
Frame 150 with disk hidden
Frame 152 with disk hidden

This seems to produced a valid animation for me in 3.1.2 with Cycles, so you may either be facing a bug in the version of Blender you're using, or a Luxcore problem.  But you didn't include a camera, so I may have guess a camera position that doesn't show the problem.  Maybe place a camera and check if it is a Luxcore problem by rendering just those frames with Cycles?

@MartyFouts: Please see my edit. I also uploaded a new .blend file with a camera.


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Mirror Modifier and spacing
This is my first stab at using the mirror mod and I am have a weird issue. The eye in this case is mirrored but it's not in the correct place according to my ref image. I have done the red loop and it worked perfectly and made sure to take off the ability to select the ref material totally to avoid movement.Now the question is.
How do I move the mirror object to be in place or how do I correct my mistake otherwise?

By default the Mirror modifier mirrors with the 3D cursor as the centre. Your cursor is to the right of the centre line in your image which is causing the eye to be offset. You'll either need to reset the 3D cursor or move your reference image over so that it's centred relative to the 3D cursor. If you upload your blend file (https://pasteall.org/blend/ ) and paste the link here we can see what's going on. Since you have a reference image you'll need to pack your image into the Blend file via File > External Data > Pack resources and save it before uploading.

Thanks
http://sendanywhe.re/W366CPLM
Here is the link

Small follow up. To the attached.
I have not applied transforms and after I did the positioning is much better but still off

You can see the mirror axis (thin blue line) is not aligned with the center of your reference image. Move it slightly to the right

@Gorgious please see updated image. I re did this a few times to try and resolve my issue.

@JohnEason forgot to tag you

No problem. Are you sorted now?

@JohnEason
No. I kind of gave up.
I recreated this 5 times today with the same result.
I figure I will try once more>

One thing I noticed with the file you uploaded (once I'd finally managed to download it...) is that you have the origin of the eye mesh near the centre of the eye. For the mirror modifier to work the origin must be at the 3D cursor, so select the eye mesh in Object mode and use the Object > Set Origin > Origin to 3D cursor menu option.

Still not aligned https://i.sstatic.net/sYYkj.png

Thank you all.
It's resolved. Inches matter @Gorgious and thanks John

@JohnEason I'm a bit late to this party but since when does the Mirror modifier by default use the 3D cursor as the center? By default it uses the object's origin and is set to  mirror on the X axis (which in this case would also be the local X axis, not global). So whatever was wrong with this model (cannot check since it wasn't uploaded on blend-exchange), the fact that the 3D cursor was a bit offset is not necessarily a problem for the Mirror modifier... the origin is unfortunately not visible in the screenshot.

@GordonBrinkmann Only 6 months late! :^) I'm not sure what I was thinking when I said that! The object was actually off-centre from the origin as Gorgious showed in his comment so correcting that should have sorted the problem.

Yeah, I just stumbled across this because I answered another of the OP's question and just looked if there were more unanswered questions.


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Volumetrics and why mine is not working so well
So I have a light that is shining through some Gobos behind my sword.
Now the problem is the cubes are not really blocking the light enough to provide nice effect. Why would this be ?
I am new to volumetric so I might be missing a key step

After correction suggestions

It’s not because the cubes aren’t blocking the light enough, they’re completely opaque. It’s either because this is EEVEE and the volumetric resolution is too low, or because the light parameters are off (maybe the radius is too large) so the shadows are fuzzy.

I agree with @The LabCat and since this is a problem with shadows thrown by light in volumetrics, it would have been nice if you had included screenshots of Eevee's Volumetrics and Shadows settings as well as the light's properties.

Added a screen shot from eevee @GordonBrinkmann

Your quality settings for Volumetrics and Volumetric Shadows are quite low. Especially Tile Size and Samples. Here is a comparison of your settings on the left and higher quality settings on the right:

This is only for a higher quality of the shadows. One of the reasons the cubes are not blocking enough light is not the fault of the cubes, but the brightness of the environment. Your world background is not very dark, and of course this lightens the volume and the shadowy parts of the scene as well. Here is a comparison between a brighter background and a darker background:

Of course the volume inside the spotlight cone will never look completely dark where it's shadowed by the cubes, because you are looking at the shadows through the surrounding volume that gets light. But one thing that can help increasing the contrast between light and shadow in the volume is the Anisotropy setting in the Volume Scatter which is kind of giving scattered light a preferred direction (simply spoken). Here a comparison between the default 0.0 value and 0.7 (but never use the maximum/minimum 1 and -1):

Last but not least - which doesn't matter in your scene since you have Soft Shadows disabled - what can make a difference is the Radius you set in the Light Properties. Your spotlight looks like it has a large radius (the circle around your light), maybe 1 m or 1.5 m, which can mean objects are not getting so much shadow because either the shadow is very soft or the object is even inside the light radius. So if you would have enabled Soft Shadows, here is a comparison of the shadows thrown by your light with e.g. 1.5 m radius on the left, and a smaller light with a radius of 0.01 m (like a small light bulb maybe) on the right:

Thank you, Make changes as suggested. My light is / was 5m in diameter


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Beveled cylinder cutout
Despite being more proficient in Blender than last time, I'm still struggling with round shapes. Currently I'm working on a small part of a model - a fluid intake. However, I can't seem to create a beveled cutout without breaking the round shape of the base cylinder.
Leaving the edges (see picture) unbeveled isn't an option either, as it will leave the hole as an deformed blob.
How can I solve this?

It seems hard to do it with a 16 vertices cylinder and with Bevel modifier. But here is a hand-made topology on a 32 vertices cylinder that seems to works:

[Blender 2.80]  I made an object similar to yours and discovered that applying a bevel to the edges "did" distort the walls of the cylinder when "all" surrounding edges were selected at once.  So I tried to apply the bevel to the edges in stages.
First I beveled the 2 bottom edges (.05 amount), then just the sides and lastly the top edges and it worked... with just one division bevel.  I tried it again with a second window (same staged process).  This time I applied 2 bevel divisions and found that the corners were not well done.  But, with some manual refacing it worked.  It wasn't elegant, but it worked.
This may or may not work for your needs.  And, I hope this is what you were referring to?


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Rigging complex mechanical shapes
I want to rig a small mechanical interaction between two pieces of metal.
In theory it's simple: the upper lever should get pushed up by the lower one (which is already driven) and then drop down - while always keeping contact.

However, due to the large contact area and odd shape of the elements I cant make this work using the regular constraints. What is the right way to rig such an interaction?

Do you want to get the reasonably convincing appearance as in  the video above  ...  or something more complicated to simulate any two shaped levers?  Physics simulation?

you could completely fake the rotation of the right one with some shapekeys, but as atomicbezier says, it all depends on what you're trying to achieve, are you trying to simulate physics?

The whole thing is part of a single mechanism which will be re-used in 8 different places. The speed of the bottom lever isn't constant, and the upper one needs to stay in place if the lower one points down and amplify its motion at the tip if it gets pushed up.
Since its always the same interaction im trying to avoid physics, but the important part is that it looks good and the lever is in the right position.

Can I make the following assumptions about the surface where two levers meet?
The lower lever has a convex plane and the upper lever does a flat one.

A rigging method without physics

To simplify this report, consider only two-dimensional space.
It is also assumed that the lower lever has a smooth convex curve and the upper lever is a straight line on the side where the two levers touch. With this assumption, rigging with Armature was able to solve the problem.

First, for simplicity, coincides the coordinate system of the lower lever object with the Armature space. In other words, only the upper lever slides on the fixed lower lever in the Armature space. This behavior could be realized by using Follow Path and IK constraints. Then, the behavior of bones was transferred to the both lever objects. Finally, the rotating shaft of the upper lever was fixed by using a Copy Rotation constraint.

Armature

Mesh Objects

Pro Riggers don't want you to know this one trick to rig anything!

Sometimes it's nice to spend time on a good rigging problem.  For those of us whose minds work that way.  Tetii's solution is fantastic, amazing.
Other times, you just want to get it done. Curved upper lever, concave lower lever.  And it took about as long to rig it as it took to make those lovely meshes.  What's the trick that pro riggers don't want you to know? [*]
I made keyframes:

Sometimes, the solution to a hard rigging problem is, don't rig it.
Okay, but you can't hand it to your client like that, right?  You can't say, "Okay, whenever you rotate the arm 70 degrees, make sure that you put these keyframes in."
But that's what an action constraint is for:

Now that I've made that animation, I can build it into the rig as a response.  Since I made that action by matching a rotation from 0 to -70 degrees, with linear interpolation, over 70 frames, I can just match the action to the rotation.
Is there any other way to do it?  Sure, there's a reason that those driver f-curves look just like animation f-curves:

You can just copy-paste them in.  I'll need to remap a little bit from degrees to radians by scaling about a cursor at 0,0, with snapping disabled, but that's all.
You mentioned that you don't want to use physics.  Maybe that's a principled stance against a domineering reality.  I think it's more likely that you just don't want to have to send your client this crazy scene full of empties and caches and tell them, "You have to hit play before you start animating, and I'm sorry it runs so slow."
Because there's a way to use physics without all of those problems, and that's to use physics to create those keyframes, rather than making them by hand.  All you have to do is cache your physics, 70 frames of it, and bake to keyframes:

Now, here, making hand keyframes is easy.  It takes five minutes.  Setting up physics to work right takes longer than that to get right.  (You don't want it bouncing all over, you don't want too much inertia, etc.)  So it's not the right solution here.  But for other problems, it may be.  It's worth remembering that you can use physics, without using live physics.
Plus, using physics to generate your keyframes scratches that slightly-irrational itch that many of us have that it's somehow wrong to do it to eye.  It's not wrong, but it feels better to let Blender's (not real anyways) physics tell us how to keyframe it.
[*] Pro riggers actually want you to know this trick.


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How to instance objects including particle system?
I've searched high and low and couldn't find any answer to a seemingly simple problem. I have a sphere with a particle hair modifier applied and I'd like to instance this multiple times using geometry nodes. The particle hair somehow gets ignored on the instanced objects when rendered with Cycles. How do I do this? Thanks!

I can't tell you the reason that your particle system doesn't show up in rendered mode (but does in solid mode). Your approach also seems to work in Evee.
However, it does work if you do it the other way around; rather than adding a Geometry node modifier to the instanced object (PomPom), instead create the mesh (Cylinder) you want to use for distributing the objects and add the Geometry node set-up to that:


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Slow Workflow with RTX 3060
I am quite desperate, because I just bought a new laptop (XMG CORE 17 - E21qzj FHD i7
16GB 1TBSSD RTX3060 W10H) and I tried to adjust all the settings, but it is just so slow.
Right now I am trying to model a body-suit, but it just takes ages to even move one plane in edit mode, both in EEVE and Cycles and both without even showing the rendered view.
I really fell in love with blender, but right now its complicated.

Here is the file (565 MB): https://drive.google.com/file/d/1ryDi1LNruFc7doZIzxrzS-Lhhz7EQN3f/view?usp=sharing

Hello! That is weird, I have a 3070 and it works perfect. A 3060 should be more than enough. How large is your file and how many vertices does your model have? Your settings look fine to me. Can you also explain how and when it is going slow?

The RTX3060 will speed up rendering (when using eevee and cycles) but won't help the viewport significantly (eg. for modeling). Seems like you added several particle systems on top of the character which is most likely your issue. Try to disable them and see whether that helps to add your plane.

Thank you already for your answers, great how fast this works. @DarkSoul: So my file size is 565MB. ,

@brockmann  When you say "disable" do you mean hide? I already hid all the other things, and also disabled it for rendering. Is there any chance, to make my workflow faster? I dont know, but I just have the feeling that my computer is so slow with a lot of things :(

I guess there is something wrong with your scene, suggest save a new version of your file and try to delete all extra tiny bits (like particle systems) until you figured out the issue or provide the file so we can have a look. By judging the specifications your machine isn't that slow but not incredibly fast either. If you'd like to proof the performance (for rendering), run a benchmark: https://opendata.blender.org/ or just use cinebench.

500mb isnt that huge. Your computer seems fine to me, but I think there is something with that scene. But as brockmann suggested. Make a backup and remove all your hair/particles and see if that helps.

I think 565MB for a single character with ~250k verts IS huge. I have a char with 1million verts (multires) and file is 44MB + 10MB textures. Maybe it's the shapekeys? Blender's Rain char has ~250 MB - Anyway, findings: there is a mirror modifier on the char, it doubles all vertices. Remove it. The node setup for the bodysuit (normal map + bump node) is wrong. But even w/o it there is a strange shading and sculpting doesn't work?! I removed custom normal data, disabled Autosmooth. Still looks blocky. The Rigify armature has all control bones doubled?! What is the weird "plane" on the left?

@Blunder I think it could be because I imported it from character creator and then I also subdivided it. I started Blender only a month ago, so I am still very unknowledgeable about the consquences of certain moves. Thank you so much for all your help, I will try everything out tomorrow :) I feel a lot more optimistic than today morning :)


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How to add 2 Textures without a seam
How to get this kind of seamless transition between two textures?
I have tried adding two textures to one object but can see a seam. Any solution for that seamless transition?

create a black and white image that you'll use as mask between your 2 shaders?

Use a mask to help blend your bump map details into the texture, I don't think you'll need two separate shaders since it's all the same plastic.

I don't know how to do that can you add a screenshot or something?


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Rice meme simulation
I am trying to simulate the "rice challenge" that is the latest meme with them kids, see this youtube video for a fun example.
This is my best result so far:
  (Video: https://i.imgur.com/KxlzB84.mp4)
which isn't quite there yet.
Any general advice on how to approach this? A particle system is the obvious solution but I'm struggling to make it work.

Please do not use external links in the question if at all possible. Describe the rice challenge, screen shoot your results, or maybe use blend-exchange.com to share your blend file.

@ZargulTheWizard I tried to embed the gif/video but I don't have enough rep, so perhaps someone else could edit it in for me. (If .mp4 cannot be embedded, here is a .gif). Y'know, a gif is worth a thousand pictures...

Try converting the particle system, and parenting it to the object. Then delete the particle system.

here the "long story short" - so i assume you have some experience with BLender.

make a text

convert to mesh

remesh modifier

add particles, tweak some settings

add plane with collision, tweak some settings

rotate text mesh so that is lies horizontal on the plane

animate the plane with location movement to positive z axis and some rotation on x axis

enjoy your rice challenge animation

Result: https://youtu.be/wAtmM0UhLQo
Video tutorial: https://youtu.be/sz-6LapA_yk

This is great, thanks! I really don't understand the downvotes, could someone please explain what's going on here?

thank you, you are welcome. Well....you will learn that some people just want the official rules to be kept...they are not really interested in people helping people, but their main focus is playing sheriff. Give people power...and they will misuse it ;)


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How to change proportions of a model after it's rigged?
I have a mesh and rig of a human made with Makehuman.  I want to shorten the neck on the model, but can't figure out how to do it without having the rig stick out from the body.  My naive approach was simple.  I selected the vertices in the neck, scaled them in Z, moved them down to the shoulder, and moved the head down to the neck. That worked, but the rig now sticks out of the top of the head.  I tried scaling the neck bit of the rigging, but that just changed the size of that segment, and nothing else.
I could simply make another human model in Makehuman with a shorter neck, but it seems there should be a way to do this.
Is it possible to deform the mesh and the rigging at the same time?

When you edit the mesh of a rigged model, you also need to edit the armature (if you don't want to have any bones sticking out). Depending on how serious the changes are, you may have to adjust the weighting of the bones (keyword: weight painting). That is, select the armature, go to Edit mode, and select all head bones and only the head of the neck bone to shorten it. Then move them down as much as needed.

Generally speaking, the procedure could be: use the rig to get the new proportions and pose (maybe scaling neck bone on Local Y axis, and adjusting Head bones if necessary).
When the new pose is ok, apply the armature modifier, so that the mesh is permanently changed in its Rest Pose.
Then select the rig, go to pose mode, select all bones (even hidden ones, turn on all bone layers) and press Ctrl A > Apply pose as rest pose.
Then add to the mesh a new armature modifier targeting the rig.
Some rigs can break after this procedure (if they use Stretch to constraints or other mechanism which rely on fixed values), but generally it works.
Weights will not be affected by this procedure.

Thanks.  This worked for me.


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Shadow only showing on playback
Any idea way i am getting a different shadow on playback ?.
When i click the play head, scrub or play. i get a shadow,
on stop and render i get a totally different result

Hi! Can you please share your .blend file so we could better dissect the problem? Upload it to https://blend-exchange.com or something similar, please.

Hello and welcome, Ziv.  Instead of posting an answer with additional info, please [edit] your original post.  L0Lock took care of this one for you, just info for the future and I didn't want you to feel bad when your answer on this page is deleted.

This is due to how shadows are calculated in Eevee when "Soft Shadows" is enabled:

When this is enabled, it first calculates hard shadows and soften them afterwards. But when in playback or moving our viewport around, it doesn't have the time to soften the shadow before a new frame is display, hence you see the hard shadow instead.
It's not a big deal on itself, the final render will be fine, it's just the render preview that is a bit biased for performance’s sake.
In fact, this isn't the only effect that can be significantly impacted during viewport playback or movement, it can also impact the ambient occlusion, volumetric shaders, bloom, reflections, ... Pretty much everything.


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My render is looking transparent
My render is looking transparent. This is how it's looking in the layout:

And when I render it, it's like transparent or something

Please help me. I started to learn Blender yesterday with a YouTube video tutorial, and I'm getting these problems.

Hello and welcome. Can you attach your blend file? https://blend-exchange.com

Hello, maybe check the Object panel > Visibility > Holdout option?

i tried to turn off hold out but it didnt work

Check if Holdout option is enabled, disable it:


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IK leg flips Upwards
I'm currently advancing my rig with IK, and ran into the problem of the leg flipping full 180 when positioning it upwards.
The First picture is showing how it wrongly flips. I of course want the leg to be positioned correctly when being posed upwards.

possibly a wrong chain length.  check the IK constraint and make sure the chain length is set to 2.  Otherwise, please add a blend file showing the problem to your question. (How to add a blend file)

@MartyFouts The chain length is set to 2. I honestly don't want to upload the Blend file as it feels uncomfortable to do so.

You can strip the file down to just the armature and upload that.  Otherwise you haven't given enough information to help diagnose your problem.

@MartyFouts "There was an internal error attempting to complete your request"

sounds like you are using 3.x and have compression enabled.  Can you save it as a 3.0.1 or earlier file without compression?

@MartyFouts compression is deactivated and it's a 3.0.1.

I guess you've hit a bug.  Do have a Google Drive account you can put the file in and post a URL for?

You can also try adding the file to https://pasteall.org/blend/

did you check to see if your test rig reproduces the problem, because when I open it with 2.93.6 or 3.0.1 it seems to pose just fine.

@MartyFouts Try dragging the LeftFootControl or RightFootControl in pose mode far up.

That works, but it does remind me, in edit mode you should bend the knee a bit forward to help the IK solver know which way you want it to bend, even with a pole target.

@MartyFouts I meant really, really far up, as far as possible, like a ballerina doing that well known pose. When I drag the foot controllers that up the foot and leg 2 rotates into the wrong direction.
I made sure the knee is 0.001 forward which helps the IK solver, it's not a problem.

First, in Edit mode, always bend the knees a bit forward.
The Pole Target bone is here to make the knee bend in the right direction. If your knee is high and go further the pole target, and if you don't change the pole target position, your knee will simply rotate 180° to keep pointing towards the pole target.
So you either need to parent the pole target to the IK controller so that it will move up as well, or you need to keyframe it, so that it will always be in front of the knee:

Thank you for the idea, I also thought of something like that. But this only helps to a certain degree, if I move the foot control too much up it flips again, even with the LeftLegPole set as child of the IK controller. It does follow and stuff, but it just flips again.

it is still the same problem, it's because at a certain point, even if you've parented, it may not help enough, and you'll need to keyframe the pole target, I don't think there's any way around, the IK needs to know in what direction it is supposed to bend

thank you for your help anyway.
In what way do Animators then animate really flexible acrobatic characters? Without IK or do they switch around when it's needed ? IK is meant to automate and optimize working steps. If I have to animate without them, this will get tedious very quickly.
Is there maybe another way of automatically positioning bones without IK ?

There must be a way like disable the IK and use the default settings, or keep it, but also create an IK for the thigh, and create a controller at the knee position, etc... it needs some tests

I figured it out myself on the Answer. Thank you for your support anyway :)

So what solution have you found that works for you?

Is an Answer to this question at the Top.

oh ok, fine then  ;)

"IK is meant to automate and optimize working steps" Not really. The only case where IK automates anything is when you have a chain link from point A to point B. IK will handle the inbetween chainlinks. That's it. A leg is nothing but a 2-links chain between a hip and a foot. Good rigs give animators many options to control limbs, and one of the bare minimum is to be able to switch between IK and FK and key that change though time. Ideally they also offer a way to snap between each other, as well as different location and rotation spaces for the ik controller, auto shoulder, elbow IK, ...

I found a solution myself.
IK without pole target, setting the knees a bit wider than needed forward. This way I can rotate with the IK controller as many spins as I want without having to rely on any poles at all.
Still, thank you all for your ideas and support, It was still very informative :)


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Rigid Body: Object sinks into another, compound parent
I'm very new to Blender, so maybe there is a simple solution. I just learned the Rigid Body animation. My aim is to let a somewhat simple object (a carrot by wojtekgr from here) fall onto a plane. However, it always fells through the plane. Directly setting the carrot to a rigid body (with convex hull) has led to other errors, therefore I remodeled the carrot with a cone and a cylinder. I read that the compound parent setting can help
I have used the following settings:

plane → passive, convex hull
carrot → active, compound parent

cone → active, convex hull
cylinder → active, convex hull

This led to the following obviously bogus animation:

So the carrot (and the underlying cone) somehow "sinks" into the plane. Is there a way to fix this?

pro tip 1: you can't embed videos here but you can ember GIFs. pro tip 2: videos on Imgur are also available as GIFs, just manually change the extension in the link.

Thanks for correcting my typos. However, the Imgur GIF seems not to move (vs the mp4) and you edited it to be a picture, didn't you? I even tried to convert the mp4 to a GIF with ffmpeg but it gave me a 221 MB file (without further encoding settings applied).

hm nope my bad i mistakenly used BSE's picture insertion tool instead of manually inserting the gif link, and it automatically converts into jpegs. But the gif link doesn't seem to work anyway, so i made a new one with fewer fps

Units and measurements
You simulate physics, so scale and dimensions matter. Your carrot is scaled down to 0.1, yet it measures over 8 meters long, and its rigid body mass is 1 kg.
First, set your carrot dimension to a more reasonable dimension, like 15-20cm long. Scaling it to 0.002 gives you a 16cm carrot.
Then, Apply the scale using ⎈ CtrlA > Apply Scale so that the current dimension of the carrot is the normal "1" scale.
Then in the rigid body settings, set the carrot's mass to something more like a carrot, like 200g.
Don't forget to do this on your carrot model, and also on your other collision objects.
Then move your carrot closer to the ground because it is otherwise three stories high, and the simulation should work just fine.
Collision objects
Just a personal preference but I am not a big fan of the compound parent system in Blender, I find it way more reliable to either use the other options or use one parent object modeled specifically for the physics simulation.
The only reasons you would want to use a different object for controlling the physics is for performance and customization: using a different mesh allows you to go lower in mesh density and avoid convex shapes, which is easier to calculate, and also abstract some aspects of the simulation like artificially inflating/deflating the collision mesh in some areas to make other objects meet at the right point.
Here I made one using a duplicate of your carrot, removed everything but one edge loop, and extruded a few times. Set it as parent, removed the physics settings from the carrot and put it on the collision object instead:

Thank you very much! It worked fine and explains my error.

BTW, I was asking myself: Even if a baloon of 8m height and a mass of 1kg falls onto a plane (like my setup was before), it shouln't sink into it. Is this an error/property of the solver? So it works only for "real world setups" since it (only) approximates the physics?

i don't know what you did, but "normally" if you wanna do a rigid body simulation with compound parent, you won't use convex hull but the given "easy" geometric shapes which Blender provides: cone, cube, ...

If you choose one of these predefined shapes (except parent compound and mesh) you will "see" the collision object.
Make sure the collision object matches with the mesh. You can do this either in edit mode and change the mesh and/or by using the delta transform panel.
So i did that and result looks like this:

Remove the cone and cylinder objects, select the carrot, apply the scale & rotation, in the Physics panel choose Collisions > Shape > Mesh and it should work.


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3D Render Completely Dark Even With Lights (Cycles) - Blender Version 3.3
Whenever I go to the 3D viewport Render tab or go to render an Image, my model looks completely dark. The outline of the model next to the floor of Blender is there, it's sort of like there is no light, however, I have multiple light sources. I don't know what to do to fix it.

I don't know what all you need, so if there is anything else you need me to show you please tell me and I will try my best to provide them.

Please share outliner also

Could you share you blend file? (use blendexchange)

How do I share he outliner?
And here is the .blend:

Hi. Please don't post essential information like links, file downloads or additional details in the comments section where it can be easily missed. Instead edit them into your original post with the [Edit] button above. Comments are transitory by nature, are hard to index or search for, and may be erased at any moment.

Okay. Thank you. Will do.

My exposure in the film tab was set to 0. Which is why everything was dark. I changed the exposure and I could see my model again. I must have accidentally changed it when I was optimizing and trying to understand what all of the settings were.


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Create Hair angel-Ring with blender nodes
Hi I want to know if possible to achieve this effect with nodes in blender.
I have a texture .dds (i will upload the model and the texture at the end) that needs to act as a cubemap to create the hair angel ring. it should looks like the white part of the hair in the image. I also upload the video on how it behaves in respect to the camera
https://www.youtube.com/watch?v=yLiQIvfKALQ
the problem I have is that when I tried using it as a cubemap it uses the mesh geometry and looks broken not as a smooth curve. I would like to know if there is a way to use that .dss texture and make it behave like the video. thanks in advance.
Texture is called AngelRing.dds and model Model.fbx
This is how mine looks https://youtu.be/0bcRBQdqdis?si=eZ33p1tLduORoHhw
https://www.mediafire.com/file/rcfde2k3po33h4f/Hana_Susuki_%2528Casual%2529.rar/file

It might be helpful to people trying to help you if you uploaded an example blend file to the site https://blend-exchange.com and add that link in the question.

What do you mean by "white" part of the hair? There are two different things that can be considered "white part" of the hair.

@DanielMöller hi the .dds cube map creates both rings the upper one and the lower one. Imagine it like just one part. I uploaded the model and the cube map too.

Could you provide a proper Blender file, instead of a collection of fbx, png and dds files ?

@StefLAncien yes i will do that right now

I think you’ll need to use the camera as a reference point, but how to get the ring to be the right shape with that… you could possibly also map the ring onto a smooth otherwise transparent sphere very close to the hair, and thus fake it. You would want to make sure it could only be seen over the hair though so it didn’t peek past the edges of her head to the sides.

@TheLabCat the problem with that solution is that besides the cubemap texture my model have a noise map texture to create those peaks on the halo ring and that uses the UV of the hair mesh for that noise texture. if I just project from the sphere I wouldn't be able to properly use that noise texture

I did not understand what you meant by peak:, but I meant for the sphere to be how you see the ring, sort of like if she was wearing an atom punk space helmet or goldfish bowl on her head, but the only part that was visible was the ring. In other words, fake the look of a shine on the hair by putting it above the hair.

You need to "pack" the resources in the blender file, otherwise no texture will appear.

@DanielMöller oh really sorry i just uploaded it


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How to make different curves to move at constant speed?
in my complete scene i have 3 curves and 4 empties:
the curves starts and ends at same point.
the first 3 empties have: 1 follow path constraint with the target being one of the curves for each empty.
the last empty have 3 drivers that take the z location of all the 3 empties mentioned before one control each axis (x, y, z) shown with the last image.
what im having problems with is that i wanted them 3 to move from start point and last point in parallel but since each curve have different lenght each one (even do they start and end at same points and time) i dont know how to achieve this and still obtain the location values of the empties to work with the main empty drivers. thank you in advance
here it is the blend file in case someone can help: https://www.mediafire.com/file/hk8fhwfhes2kvzp/2.blend/file
)

as you can see in the tremendous amount of answers and comments....your question might lack of interest/informations. So pls provide blend file so we can check it out since we have no idea how you animated it and why the speed should be the same. thx. and maybe adding an animation/link to your question how you want it look like would be great. Just one picture doesn't make clear how the animation should look like.

and just fyi if you don't know: if you click on "animate path" in follow path constraint and the length of the paths are different, of course (!) the animated objects will have different speed because Blender uses 100 frames to animate them from beginning to start if you didn't change it manually

Animation along curves is evaluated based on curve factor.
When curves are of different length, the objects traslate at different speeds as long as they have to arrive at the same time traveling different distances.
I assume that you want your objects to travel in parallel (first picture) while still on the curve trajectory.
This is a common case when animating data graphics. As an example, in animating stock values a vertical line displaces in x representing a date and different cursors translate along evolution curves to point the stock value at that given date.
There is an approximation to the problem through geometry nodes.
Applied to every curve:
With Raycasting, project the position of an empty (Object info node - Relative) into an extruded version of the curve (Curve to Mesh) to obtain the position of the "cursor" object (Object info node - Original).

Raycast traces down the ribbons, so the curves can have different lengths, shapes and number of vertices. The cursor objects will traslate parallel to the empty.
Be careful with self crossing curves and not traslating the empty beyond the ribbons (nothing to trace below). The empty can be position constrained with Limit Location to avoid that.
If you want the cursor objects to also rotate along the trajectories, use the Hit Normal data in the Raycast node.

hi thank you so much for the reply this is what i wanted to do but this approach doesnt work with my setup, i updated the question to be more specific and also uploaded my blend file sorry. because i need to retrieve each z location of the values of the empties because i have a main empty that have drivers in it that use the z location of the other 3 empties moving along the curves.

@souleater, why don't you edit the question and tell us more about the situation. What is the purpose of this main empty? What are you trying to do? This seems like it sort of is an XY problem already and it seems you are heading in the direction of making it "XYZ" problem and we are running out of alphabet...

@Martynas Žiemys sorry, the main empty needs to move x,y,z using the 3 curves i shown above, i use 3 empties and the main empty use the z location on the others 3 values to obtain this, what i want is that they move in paralel like the answer above but still obtaining the location values so the drivers works, i now its a weird and specific question but its because i notice this game use bezier curves like this to make camera works https://youtu.be/CfVY8rzUJu8 and im trying to do a python code for that but im stuck here because each empty move at different speed

@Martynas Žiemys the best result could be moving one empty to x axis and the other 3 empties move at parallel with that  axis but moving up and down using the curves, thats what i want.

All you wrote sounds like a huge XY problem and huge waste of time for anyone who might attempt to help to be honest. What do any empties have to do with the linked video?

@Martynas Žiemys i understand i think i can figure something out with the answer here thanks for try to help


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Bpy: Traversing the side of a 2d connected edge set
Background: Keping an even thickness on a 3d curve is tricky, so i want to throw together a python script that solidifies a 2d edge set, giving it an outline with a even thickness.
To create a foundation for that, we first need to be able traverse the left (or right) side of connected edges.
On itself this would require identifying connected edges, but there are some edge cases i don't know how to deal with.

Intersections: a vertex may be connected to multiple edges, and we need to traverse the one with the smallest opening angle (?)
Two sides: if an edge ends, we need to continue on the other side of it in the same direction

A set of lines and the found points (red or green depend whether we start outside or inside). These are offset along the normal, but that is not necessary.
Efficiency is not important, any help is appreciated!


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How to join two objects
At first, they were the same object, but after saving it they got separated

before it looks like this
How to combine both objects

Select the 2 objects and Ctrl J?

Ctrl J was Combining two objects, but the object did not look like before.

OK but nobody can tell how it happened, if you want one unique object you need to join with Ctrl J, then in Edit mode select the icing with L and move it as you want

As @moonboots says, we cannot tell how it happened, we cannot go back in time and see how the objects looked and were set up before. I can only imagine there were some modifiers or whatever or changes in scaling etc. that somehow caused this. I can only highly recommend (because I'm quite sure this does not happen in the donut tutorial) to pay close attention when watching tutorials as a beginner, because you might have done something accidentally wrong.

So I just saw in your file you have put animation keyframes on the icing and the donut which will keep them in the location where they are. I guess then you have probably moved them in a different place without fixing this with a new keyframe. Then saved the file and since there is no keyframe for the new position, Blender reads the existing keyframes and puts the objects there. Or simply changing from one frame to another will reset the location as well.

Move the first one down by selecting it, pressing control G, then Y and move your mouse down until it's at your desired location. Once you've done that, hit ctrl-J to join them together.

I think you can get them combined by selecting them both and Cmd + J to join them or Cmd + P to parent the top layer to the bottom layer.


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UV Mapping, XZY coordinates to UV coordinates
I'm kind of new to this and found myself having issues wrapping my head around UV-mapping. (also not 100% sure if this is the correct forum for my question)
I am working on a small rendering engine (perspective software rasterizer) and I can't figure out the correlation between UV coordinates and XYZ coordinates. I'm using blender for modelling and exporting the vertices of the triangles via a python script, writing those as CSV and letting my engine read them in.
So far so good, I then tackled texturing those objects. Created UV maps in blender, worked, but I'm not sure how those are supposed to come into play. When rendering my models I'm solely accessing the vertices of the triangles of the object (XYZ). How does one get the corresponding UV coordinates?
I'm sorry if this is a stupid question, but I didn't find any literature about this. Or am I approaching this incorrectly?

uv data is in the face loops, either in bmesh or object data uv points are between 0.0 and 1.0 and place the vertex on the source image, 0.0 being one side and 1.0 being the other.

@sambler aren't UV coordinates actually floats? They are desirably most often between 0 and 1 but can actually take any value like for tileable textures, right?

@DuarteFarrajotaRamos yes uv's are float values. 0.0 is one edge of the image and 1.0 is the other, and 0.5 is the centre of the image. Values outside that are wrapped around, so 0.5 and 1.5 correspond to the same location on the image.

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


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Stop Blender trying to connect online
I have discovered that when my internet connection is disabled, Blender loads up much faster. I would like to find a way to make blender think that my internet connection is disabled, when it isn't. This way it wouldn't matter why it's trying to connect online (e.g. some addon checking for updates or any other reason).
After hours of trying to figure out how to make blender load quickly, this is what I've found:

Blocking outbound blender connections via firewall works, but it is still much slower to load vs when the internet connection is disabled.

Removing addons that might try to connect online helps to speed up blender loading, but blender always loads faster when the internet connection is disabled.

Any help would be greatly appreciated.
Note: running a VPN connection stops blender trying to connect online for some reason (so possibly this is related to some proxy setting). However, I would like to find a solution to make Blender not even try to connect in the first place, which is what happens if the internet connection is disabled.

Aren't you just using a third party addon that connects to the internet for some data, typically an online asset manager like Blenderkit or something? Because AFAIK Blender is designed to not use anything online out of the box.

Blender, as a principle, does not have any modules that check or need internet connection to work. It is very unlikely that this slowdown you're talking about is due to Blender itself; probably a rogue addon--find out which one and disable it. If you're right and internet connection slows down Blender, it'd be a bug (report it); if it's not a bug, then it's a general question about software-internet relations on Windows, neither of which is something we can answer here.

Yes some addons must be causing this online checkup since after removing all addons Blender loads normally/quickly. I though that because those scripts run within Blender, there must be a blender setting/python line that blocks this call, since it doesnt try to do this when internet is disabled. In other words, instead of constantly trying to keep track of which addon/python file has one line that checks fonts or updates or whatever it is, Id like Blender just to not check anything online for any reason. Is this not possible?

@Downat3D I guess not that it's possible, since Blender itself is build to work without any network connection - at least, my resource monitor shows no network traffic when starting up Blender. So why should they implement a general network blocking function if there are only some (third party) addons that would use the connection? And I guess it's a functionality of the addon that the developers supposed to be a good/necessary feature, why should they want it to be restricted...?

i agree with L0Lock and had also some issues with BlenderKit (which not only was buggy and has thrown errors) but also displays annoying popups...so i just disabled it

Thanks everyone for contributing. I was hoping there was some hidden way to disable any internet connections within Blender as a way to customise the user experience and prevent some random stuff and libraries downloading. I guess that kind of thing is something left to the OS itself. I just feel like Blender must first listen to some code that tells it to check online, and therefore there should be something that controls whether it listens or not. Even if this exists, it's probably not in some python settings file.


text:
My Principled BSDF is not fully showing up
When I go in the Shader Editor, my Principled BSDF is much shorter than all the ones I see in tutorials.
This is what it looks like when I do it

This is what it looks like in every tutorial I see

Since version 4.0, the Principled BSDF have seen quite significant changes, both in therms of user interface and functionality:

The main "global" properties are exposed as is, while other "layers" are in individual panels that you can open, toggle ON/OFF with the Weight property, and the settings inside are a bit different from the old Principled BSDF.

The base layer is a mix between metal, diffuse, subsurface, and transmission components. Most materials will use one of these components, though it is possible to smoothly mix between them.

The metal component is opaque and only reflect lights. Diffuse is fully opaque, while subsurface also involves light scattering just below the surface. Both diffuse and subsurface sit below a specular layer. The transmission component includes both specular reflection and refraction.
On top of all base layers there is an optional glossy coat. And finally the sheen layer sits on top of all other layers, to add fuzz or dust.
Light emission can also be added. Light emits from below the coat and sheen layers, to model for example emissive displays with a coat or dust.

Source: Principled BSDF — Blender Manual

Christopher 3D did quite a few videos going in detail about the shorcomings of the previous Principled BSDF, how the new one solves them, and how to use it.
See his playlist: Blender 4.0 Feature Videos

I want to make it see-through with the transmission feature.
In the video when he changes the transmission it looks see through when for me it looks like a slimy blob

That's a different topic. First, if you are using Eevee, there are additional settings to change in order to get transmission to work properly, there are many topics talking about this so please search for that first if you use Eevee. Otherwise, please make a new question, and include screenshots of what you want to achieve, the result you get, and your shader so that we can see what you did.

This is how the Principled BSDF looks in the latest versions, they made it shorter but everything is about the same, you need to click on the small arrows to unfold the part you want.

I have done that but it doesn't seem to work. I want to use the translucent feature but it doesn't change anything.

translucent is not part of the Principled BSDF, you need to press Shift A > Shader > Translucent BSDF to get this shader


text:
EXR Output Overexposed
Saving a render as openEXR (single layer) is very overexposed compared to saving to PNG. I've viewed the .exr file in Resolve as well as other video/image editors. Everything appears brighter and with excessive contrast.

It's because of the different Color Management: when you render a scene in Blender, all light informations that get created for every pixel lay in a range that can go from 0 to nearly infinite, this realm is called "scene referred".
In order to be able to view the render on an ordinary monitor (that can handle only a 0.0 to 1.0 value, or 0 to 255 if you count in 8-bit format) the scene referred values are projected to the 0 - 1 zone, via some kind of "View transform": generally Filmic or AgX, with different "flavours" (medium contrast or high contrast) choosen by the artist. This transformed color management is called "View referred".
PNG saves the view referred scene, which applies also some kind of Gamma correction, in order to follow our eyes' sensibility.
EXR saves the scene referred data, in a linear fashion, without any Gamma correction and without any View transform (no Filmic, nor AgX).
PNG is better if you want to publish the image "as it is" (even if it cannot handle some transparency situations, search for glows disappearing problems related to the PNG format itself).
EXR is far better if you want to post produce the image, because it retains much more informations about the scene, and the linear format handles better all math operations which are tipically performed during Color grading and compositing.
In order to see the correct colors in DaVinci or others softwares, you have to apply to EXR a minimum of two color transforms (depending on the Color Management workflow you follow): a simple example would be a DaVinci standard LUT that you can find under VFX LUT menu, called "Linear to rec709", followed by the view transform you used in Blender (filmic or AgX).
In order to mantain the advantages of Scene referred linear EXR data, you have to apply thoose transformations at the very end of the process (and during monitoring the composite).
The setup for having automatically DaVinci recognize EXR and applying correct color transforms can be a little tricky, but it brings much more powerful and professional looking composite and Color Graded results.
In my picture I'm showing that it's possible to install all flimic and AgX View transform on Resolve (with a simple copy and paste operation in the correct folders, from Blender Color management files to DaVinci's ones), while the standard VFX - Linear to rec 709 comes with DaVinci by default.
Search for Color Management tutorials, with keywords "EXR, filmic and AgX" for more infos.

Thank you so much for this complete and very informative answer! This was very helpful.

I have just faced the same issue. What helped for me was to link driver for compositing Exposure Node to the Color Management Exposure value. Exported EXR renders now get "correctly" exposed - depending on your Color Management setting. This will make your image appear underexposed in the rendering view, but exported image will look correctly.


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When scripting in python, can you parent and later reparent?
Is "parenting" something you only use when the parenting relationship will never change?
The reason I'm asking is because I successfully make animations with keyframes involving parenting objects. But whenever I try to clear parenting and reparent different objects, the animations never work.
If you clear parenting, are there multiple layers that need clearing, for example, before I can parent an object that was formerly parented? I was just doing clear parent, but it wasn't enough and the animation always fails.

Thank you so much! The child of constraint is what I needed.

Parent relationships are indeed meant to be permanent.
If you need dynamic relationships, you should use object or bone constraints. They all have a factor which can be animated among other things.
The most common way to make dynamic relationships is with the Child Of constraint, because it can store an offset from its parent object. But there are plenty other interesting constraints: ones that copy all transforms or just the location/rotation/scale, ones that limit transforms, damped tracks, distance constraints, ...


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Can't figure out how to export transparency (Glass, Ice) to a gltf binary file
I need help to understand how I can export this item with same transparency, colors and reflection style in glTF binary for a GSAP website!
I'm pretty noob in blender, can someone explain me step by step what to do?

https://blender.stackexchange.com/questions/57531/fbx-export-why-there-are-no-materials-or-textures

While glTF supports basic materials that use the Principled BSDF node with bare values or UV mapped image textures as inputs, the final render is always up to the render engine.
So to answer your question here, the best you can do on Blender's side is to make sure your material is set up as mentioned above.
As for how the render is done in your target software, that would be out of topic on this website. But GSAP seems to use Three.js to handle 3D models, so I would refer you to that manual page that mentions alpha handling and whatnot:
Materials – three.js docs


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apply all shape keys to selected objects except certain shape keys
I want to apply all shape keys to selected objects, except the shape keys that have the word face in the name. How can I do that? I have this script that applies all shape keys to selected objects, but it does not leave the shape keys that have the word face in the name.
import bpy
scene = bpy.context.scene

for o in bpy.context.selected_objects:
    if o.type == "MESH":
        if o.data.shape_keys:
            for k in o.data.shape_keys.key_blocks:
                ojs = bpy.data.objects
                bpy.context.view_layer.objects.active = o #set context.object

                o.shape_key_add(name='CombinedKeys', from_mix=True)
                if o.data.shape_keys:
                    for shapeKey in o.data.shape_keys.key_blocks:
                        o.shape_key_remove(shapeKey)

Formatting note: I advise using triple marks to format code instead of indenting the whole code, because almost every wrongly indented code that I have encountered on this website were formatted with indentation instead of  triple marks. Hence my edit of your question.

Your current method first creates a new shapekey of all the combined shapes. 1) Does that mean you want to preserve the deleted shapekeys as a new shape? 2) Does this new combined shape needs to also include the shape key you want to keep? 3) Does this combinedkeys need to be preserved as well? It would be quite a different procedure depending on your answers here.

Starting from this code:
import bpy
scene = bpy.context.scene

for o in bpy.context.selected_objects:
    if o.type == "MESH":
        if o.data.shape_keys:
            for k in o.data.shape_keys.key_blocks:
                ojs = bpy.data.objects
                bpy.context.view_layer.objects.active = o #set context.object

                o.shape_key_add(name='CombinedKeys', from_mix=True)
                if o.data.shape_keys:
                    for shapeKey in o.data.shape_keys.key_blocks:
                        o.shape_key_remove(shapeKey)

A few things could be tweaked:
Setting the active object
It isn't even needed for your script to work. But if you did something else that required it, it should definitely happen in the object loop, not in the keys loop. Otherwise, you would set the same object active multiple times for nothing.
For and If statement
Anytime you have a For followed by IF, you could simplify it. I.E:
for o in bpy.context.selected_objects:
    if o.type == "MESH":
        if o.data.shape_keys:

Can be simplified into:
for o in (o for o in bpy.context.selected_objects if o.type == 'MESH' and o.data.shape_keys):

Making a combined shapekey
For some reason, you make a new shape from mix. But your current code have this happen as many times as there are shape in your object. This sounds quite tedious. Plus, this function works with the "current visual state" of the mesh. Meaning, if you have all your shape keys influences at zero, the shape from mix will be exactly as your base shape.
This needs better thinking, what is your goal with that? To preserve all the additional shape keys as one shape? Does it need to include the shapes named as "face"? Does the script have to turn all shape keys influence to 1 first?
In addition, your current script deletes that shape key anyway, so it's effectively useless.
In my revision, I will assume you want to create a new mixed shapekey to combine all the ones we delete.
Since we will need to make operations on either filtered in or filtered out object alternatively, I will make a list of them instead of always making for loops with extra filters all the time. It will make the code more readable, easier to manage by having only one place to handle filtering, allows you to easily do more operation on either lists of objects, and also I think it would be more performant (I think, I'm no expert).
shapes_to_delete, shapes_to_preserve = [], []
for shape in o.data.shape_keys.key_blocks:(
    shapes_to_delete if 'face' not in shape.name.lower() and 'basis' not in shape.name.lower()
    else shapes_to_preserve
    ).append(shape)

Note that I included the "basis" shape in the list of shapes to preserve. Since this is essentially your "original" mesh on which any shapekey is usually based on, you really need to keep it to not break your object.
Also note that I matched the names with name.lower() instead of just name. The former allows to not worry about capitalization. If you want to have a case-sensitive matching, use name instead.
Final procedures:
All we need to do is:

set all to-preserve keys' values to zero
set all to-preserve keys' values to 1
create new shape from mix
add the new shape to list of to preserve (if you want to do more operation on them later on)
delete all to-delete shapes

These can be done quite simply with a few For loops.
Final result:
import bpy

for o in (o for o in bpy.context.selected_objects if o.type == 'MESH' and o.data.shape_keys):
    print(f"Found mesh object with shapekey data: {o.name}")
#    bpy.context.view_layer.objects.active = o # not needed here, but just in case, that's where you'd put it.

    shapes_to_delete, shapes_to_preserve = [], []
    for shape in o.data.shape_keys.key_blocks:(
        shapes_to_delete if 'face' not in shape.name.lower() and 'basis' not in shape.name.lower()
        else shapes_to_preserve
        ).append(shape)

    print("  Keys to preserve:")
    for shape in shapes_to_preserve:
        print(f"    {shape.name} of value: {shape.value}")
        shape.value = 0

    print("  Keys to delete:")
    for shape in shapes_to_delete:
        print(f"    {shape.name}")
        shape.value = 1

    new_shape = o.shape_key_add(name='CombinedKeys', from_mix=True)
    shapes_to_preserve.append(new_shape)

    for k in shapes_to_delete:
        o.shape_key_remove(k)


text:
Cross section in cycles in blender 2.7
I'd like to take a simple cross section in Blender 2.7 using the Cycles renderer. I would think this would be easy, and there is even a tutorial about how to do it, but that tutorial is for Blender 2.4, and does not work with 2.7. Can someone post a simple tutorial about how to create a cross section in the latest version of blender. Here is that I have come up with so far, but the edge is not sharp and I cannot figure out how to adjust it:

Also related: http://blender.stackexchange.com/q/5113/599

You could get the effect you want with your existing node setup if you add a Math node set to Greater than between the gradient texture node and the mix factor. For more control, you could instead use a color ramp node set to constant interpolation in the same place.

If I would be trying to achieve a cross section like effect, I wouldn't use the compositor but a mesh with a boolean modifier. In my opinion it's much more flexible.
To accomplish this add a cube to our scene and position it to intersect with your object in the place you want gone. Then add a boolean modifier to  the object, select diffrence for the mode, and chose your masking cube. Be sure to disable renderability/hide the cube you masked the object with.
I have created an example in which the object being cross-sectioned is suzane in a box. You can download it here. Here's the example render and viewport screenshot.

While this method works with almost any render system, the blender internal and cycles have trouble with multimaterial objects. In that case just split it into separate objects with one material each.


text:
How to change color along a curve?
I have a curve, which has been made visible by using a circle as a bevel object. I would like the color to change along the length of the curve. In other words, the curve will start red, and then change to blue towards the end.
I have figured out how to make the color change as a function of a coordinate (in this case the x-coordinate), but I cannot figure out how to get the coordinate along the length of the curve so that I can pass it to the ColorRamp.

Any ideas?

The trick is to enable UV mapping on the curve and then use UV as the input texture coordinate. Then use can use the mapping node to rotate the default UV positioning to get the gradient to run along the length of the curve. Please note I had to adjust the X/Y scale factor to get the whole gradient to show on the curve.

Yes, this seems to work! Thank you! (and nice animation!). To be specific, UV mapping is enabled via clicking the "Use UV Mapping" in the "Texture Space" section of the "Curve/Data" tab.  In the Mapping node, I found that I could leave the "Rotation" at zero for x,y,z. Also, I just used the "X-scale" and left the others at zero. Using the y-scale caused the colors to look strange. Thanks again for your help!

Thanks, I was so long looking for this :-D how did you come to those degree values? Sometimes it´s hard to figure out the right ones especially on tiny geometry ...

Material - plug UV Texture Coordinate socket into Separate XYZ node
and use X socket as Fac input of ColorRamp

Note: Add thickness to a curve (make a tube) you don't need another object for circle profile - just go to Properties editor > Object Data > Geometry >  Bevel > Depth


text:
Unable to move a mirrored part of an object
Can anyone assist me in getting a part of a mirrored object to move without overlapping into itself?
In 3DSMax it consisted of changing the view from global to local and then the whole thing moved instead of overlapping. In Blender I've tried all the local views and they aren't working.
Below is what is happening -

Take a look at this question: http://blender.stackexchange.com/questions/353/how-can-i-make-the-mirror-modifier-work-right

If I read it right, Ian wants to move vertices from both sides of mirror axis together, which is doable through modifier with a few limitation. I don't think the question is a duplicate.

A mesh data is fed through the modifier stack from top to bottom, and what's accessible through Edit mode is only the original data, not the result of the modifier stack. Modification of a modifier's output is only possible by applying it first, or through another modifier lower down the stack.
In your example, vertices generated on-the-fly by Mirror modifier can't be moved past the modifier's mirror axis, even if Clipping is disabled and the modifier is applied to editing cage. That's because it's not in the original mesh data, and its position is not stored independently but calculated by the modifier:

Modifying those vertices manually is possible after applying it, because those new vertices are now available in the original mesh data. Other modifier can also modify them if placed below the Mirror modifier, for example an Armature modifier (note the modifier stack):

or a Lattice modifier:

Just move it in Object Mode (Tab to toggle)
The Mirror modifier works according to the Origin (aka pivot) of the object - that is the orange dot that shows on selected objects - unless you specifically tell it to use a different location (by selecting something for the Mirror Object)

In Edit mode, you are manipulating the vertices/edges/faces of the mesh itself, not the object as a whole, so when you select everything in edit mode and move it about, the origin stays where it was and thus the mirrored mesh goes out of alignment:

So instead, Tab out of edit mode and move the entire object.
If you wish to reposition the origin of the object without moving the mesh, you can use Shift+S to place the 3D Cursor at some position, and then Ctrl+Shift+Alt+C in object mode to move the origin to the 3D cursor.

You may notice the Origin to Selected button in that screenshot, this is not a built-in function of blender but rather a function in my own addon that simply performs these two functions in one go since I do this frequently. If anyone is interested, I could upload this addon.

I'm not quite familiar with 3DSMax, but I guess you may be looking for the result when toggling Clipping in the Mirror modifier panel, suppose you got one.

Otherwise, it's not possible to do "un-mirror" transformation while working with Mirror modifier. You can either apply the mirror modifier before moving, or add additional modifiers below it in the Modifier stack to make further modifications, such as Lattice.

If I understand the question correctly, the OP wants to move the whole selection, not make the mesh thinner (as is the result with clipping).

That's because you're moving that piece through the mirror plane (the YZ Plane, or X axis, in your case).
The mirror plane is defined relative to your object coordinates. You can change the plane by using the Mirror Object setting of the Mirror modifier.
If you're trying to have two different mirror axes in a single mesh, or to selectively mirror only certain vertices, I don't believe that's possible at this time.


text:
How to set up cloth simulation for belt
So I have a coat and I wanted to put a belt on it. The problem is, cloth simulation goes weird especially on the belt slot part (Probably because the belt slot is too close to the edge of the belt but if I make the belt smaller it still occurs. Question is, how do I set up a cloth simulation for my belt so it doesn't glitch out?

Can you provide any geometry to test?

Ok, I've added it.

Is there a reason why you don't pin the upper part of the belt which wraps around the belly? The belt slot part has no collision. That's the reason why the belt slips through it.

I thought the belt slot has collision because it is merged with the coat. Also If I pin the belt then there won't be a some sort of "tightening" effect that the belt produces. I tried to fake it as a temporary solution by making the coat's mesh looks like it has been tightened by the belt around the belly and then pin that part for the coat and the belt.


text:
Is there a way to fill a cube up with fluid?
I am trying to make a fluid simulation render like this:

I don't want it to look like that, I just want a tank filled with water. It needs to be a FLIP/APIC simulation so I can use Effectors and more collision objects.
I know I can just do something like this:

And wait for the simulation to fill up the bowl, but that takes a long time to bake as it takes like 300 frames to fill up the bowl, so is there a way to do it quickly? If there is, I need it to be an actual simulation.
Please don't suggest doing something like this: making a cube look like water by sculpting it or adding a noise-displacement modifier and then adding a water/glass material on it as it needs to be a FLIP/APIC simulation:
Dummy model (Sorry, I'm really bad at sculpting and the lighting sucks too lol)

You can increase the flow so that the space fills faster.

Does it need to flow in? or will flow in more later?

Why the downvote?

@Blunder downvote wasn’t me, but I would like to create something like this: https://bit.ly/3yoLIhC      That’s why I need it to be a simulation.

Ah, I see. I think the mix of air and water will be challenging

Create a cube that is slightly bigger that your domain and give it a Flow Behavior > Geometry. If you want to drop an object into the water, give your object a Fluid > Effector.

You also can have additional Inflows to let more water in. (Just tested it because I wasn't sure)

sure, but doesn't he want still water?

I mentioned in one of the comments above that I would like to make something like this: https://bit.ly/3yoLIhC     So no still water wouldn’t work. And the link to the image is just a photo render, I would like an animation render

so you just need to drop objects that are Effector, not sure it will be very accurate though, the water won't be still, it will be animated by the effectors, but it is still at the beginning

@moonboots I've just mentioned it for people who didn't know (like me) so they can do a bathtub simulation ;-)

@Blunder, I don't know a lot either but from what I understand he's looking for Geometry, I guess he will have to tweak some parameters to have something realistic


text:
Mesh deforming while moving bones
I'm trying to do a simple character to try mesh rigging but when I move the bones, my mesh is deforming/changing scale.
The weight paint seems good so I don't understand the problem.

Here is a video that shows the issues:
https://i.sstatic.net/aIRY9.jpg

The weight painting is definitely not good from what I am seeing, parts of the arm mesh may still be weighted to other bones that are contributing to the weird skewing and distortion.

It's hard to tell from the images only. Can you share the file? Otherwise, check the face orientation, the weights, the vertex groups, and that there is only 1 armature modifier on the mesh. Also, the mesh and the armature must have the same rest pose when you bind them (Parent To ...). And the Scale, Rotation, and Location of the armature should be applied before the bind.

The problem was that my main body bone weight was applied to all the body...


text:
Procedural Animated Winx Glitter (Confused With This Tutorial)
I am following this tutorial on how to apply this animated glitter effect on my models, but sadly I am having a hard time understanding what the speaker in the video is saying. So I have been able to follow enough to build the actual UV Sphere but I am unsure of how to apply it to the Model.
I think he starts explaining how he does it at the 7:12 mark of this video but have a really hard time understanding what he says. I was hoping someone who knows what he is doing could help clarify things for me
Link to Video Tutorial

It looks like he's just showing 2 different versions of the same shader. The second one (after 7:12) has an image texture with an alpha connected to the Principled BSDF, but the first shader does not. He's just showing you that you still have the option to connect an image texture, should you so choose.

I'm pretty new to this still. So Does this mean that both are able to apply to the model? What I want is to have an effect similar to how he shows in the first few seconds of the video when he gives his demonstration.

Yeah, if you look close at the "demo", you can see the model's skirt has a pattern on it - I think all the image texture does (that he shows connected after 7:12) is provide that pattern, the rest of the effect (stars and whatnot) is shown in the shader before the 7:12 mark

Ok, thank you but one last question. So Does he apply the shader to the model, or does it become visible on the model simply by having the UV Sphere over the model?

I'm pretty sure they're separate - one for the sphere (no image), and one for the model (with image).


text:
Blender cloth collision not working

I have been trying to make this effect with my design. But it doesn't work. My object underneath is keep on showing thru the cloth (below image).

I tried joining both of the objects (the heart and the cylinder) and applied collision + applying collision to them separately, but it didn't work.

here is the link to the tutorial that I followed
Update:
Thanks for the reply, but it still doesn't work. Here is the model.

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

"...and applied collision + applying collision to them separately..." <-- Have you enabled Collision in the physics properties tab and then apply the Collision modifier in the modifiers tab which was added by the physics? And it's gone? You don't need to apply the Collision modifier, just add it. But Blender does this automatically when you enable Collision in the physics tab.

Have you checked the normals/face orientation of the heart and the foil to be sure it's not inside out?


text:
Blender selects two armatures together. what to do?
When I press A to select an armature, it selects both! How to solve?

I think we'll need to see your Blend file to see what's going on. You can share it via https://blend-exchange.com/ following the instructions there to copy the full link on that page. Then edit your question here and paste the link into it.

You probably have 2 armatures selected, go back to Object mode, select one armature only, then switch to Pose mode

I managed to solve it, thank you very much

Hi, welcome to BSE! This site is a bit special, in being a Q&A where we need clear questions and answers both of good quality. Please do not use the question field to insert comments or "thanks i solved it". Instead, comments should remain in the comments section, and answers should be posted, nicely elaborated, in the comments section. See the FAQ articles for more: Can I answer my own question and How do I write a good answer?.

A is the shortcut to select everything visible in the context. If you are in object mode, it selects all objects. If you are in edit mode, it selects everything in that context. The key here is "everything", not "a specific thing".
In your first screenshot, we can see that you are in pose mode on two objects. It's visible in the viewport by the fact that both your armatures' bones are displayed as being posable. Though that could also be that you actually have your two characters armatures into one, but the outliner make it obvious those are indeed two separated armatures currently in Pose Mode:

To fix this, Tab into object mode, select only one of the objects, and Tab back into Pose Mode. Or, while in pose mode, go in the outliner and click the white armature icon on the left side of the armature to make it the only one being in pose mode.


text:
Book for Blender
Kindly suggest book title and author name by which I able to learn blender completely and make animations if you have share the link of this book it is helpful for me.

Please edit the question to limit it to a specific problem with enough detail to identify an adequate answer.

It would be easier to learn through youtube tutorials (there are a lot of good ones, check Grant Abbit for example). For books make sure that they are recent, at least from 2.8 and beyond.

The software is just a tool, animation is learned independently. The first two classic books are:

The Animator's Survival Kit by Richard Williams
Disney Animation: The Illusion of Life by Frank Thomas and Ollie Johnston

Both considered as the Bible of animators. They are the two giants pretty much every western animator has to read or even consult on a daily basis.
Then you can go to some more precise domains, such as The Artist's Complete Guide to Facial Expression by Gary Faigin. It's not about animation itself, but facial expressions, which are essential for any acting shot. Or why not Game Anim: Video Game Animation Explained by Jonathan Cooper that's more specific for animation in the video game industry.


text:
How to remove object constraint from parent bone?
I am trying to use an object constraint to make a bone tip follow a path. However, when I try to assign the constraint in pose mode the parent bones also get the constraint. Is there a way to remove a constraint from a parent bone but not the child?

maybe you've confused object constraint with bone contraint, make sure that you have selected a bone in Pose mode and opened the good panel (Bone Constraints, not Object Constraints)