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How would i wrap a 3d object around another 3d object which is beveled and round and a little bit square shaped?

I want to wrap the white and black mesh around the wood mesh(the blade), I have tried every way possible and it just does not work/it twists in weird ways or just does not twist/rotate at all. (things i have tried: path/curve/shrink-wrap/object deform/lattice), please help!

https://blender.stackexchange.com/questions/21167/twist-rope-around-an-object/ https://blender.stackexchange.com/questions/235744/how-to-properly-shrink-wrap-a-torus-looking-thing/ https://blender.stackexchange.com/questions/235074/creating-diagonal-loop-cuts-in-a-cylinder https://blender.stackexchange.com/questions/120946/how-to-make-straps-of-leather-wrapped-around-sword-handle/120950#120950

A lazy way to fake it would be to create one bandage that goes 360°, subdivide it and sculpt it a bit to create the folds:

Duplicate X times, rotate 180°, tilt it a bit with the Shear tool, move the UVs so that it doesn't show the same pattern:


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How do I use image textures to "mask" metallic elements?
First time poster here.
I'm using Blender to create 3D renders of products which my company is manufacturing.
With regards to the labels that I am applying to the products, the labels will have layered elements to them, such as a matte label with metallic/glossy elements.
Up until now I have merely duplicated the "label" and hovered it extremely close to the layer under it to give the impression that the multiple labels are seen as one, for example:
Base layer - Scale: 1
Metallic Layer - Scale: 1.00001
Glossy layer - Scale: 1.0002
I know there is a way to create this same effect within one "label" using the node editor, whereby I can plug in an image texture to the metallic/clearcoat to "mask" the label so that the image plugged into those sections will appear as either metallic or glossy, but I can't for the life of me figure it out.
Any assistance would be much appreciated - I've attached a screenshot of the metallic element I'm using but if I could combine all metallic/glossy/matte elements into one that would be a million times better for us.
Thank you in advance!

Hello it's hard to understand, do you have an image of the kind of thing you want to achieve and the kind of logo image you have?

https://blender.stackexchange.com/questions/5069/id-like-to-have-portions-of-a-texture-not-glossy https://blender.stackexchange.com/questions/46424/add-a-transparent-image-on-top-of-a-material https://blender.stackexchange.com/questions/199473/how-to-overlay-one-texture-on-another-one https://blender.stackexchange.com/questions/208639/how-to-mix-three-different-shaders-on-the-same-material https://blender.stackexchange.com/questions/90064/using-an-rgb-map-to-assign-various-shaders-in-a-material/

source: Stack Exchange

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

sort: votes


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ocean animation not working
i watched a few tutorials for this and i can't understand what i'm missing out. they just type "#frame/50" or any number and then just press play and their ocean is oceaning, but nothing happens to mine

Did you bake the actions?

thanks, had no idea about that, i just tried and it's still not working, i'll just leave it motionless:)

Did you keyframe it?

Could you give a little more detail in your above post about your problem? I've done the ocean simulation before and didn't have a problem, but I don't remember all the steps. Check out this tutorial: https://youtu.be/p03fspwMY64

To fix the ocean, open the Driver Editor by right-clicking on the Time input and selecting Driver Editor from the drop down. Remove the hashtag (#) from the script. Also, you can remove Input Variables if you don't need them.

worked fine for me.  here's driver with "#frame/50":

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


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Adding thickness to image
I need help on adding thickness to the below PNG. Image I am trying to follow tutorials online but somehow they are not working for me . Would appreciate your help on this.
Eventually, we will use the boolean function to engrave this logo on another (shell) object that we need to 3D print.
Thank you in Advance
Mansi

Please show us what you are able to achieve, where your problem lies, what you want to achieve. If things "don't work for you", chances are you are doing something wrong.

Hello and welcome. If instead of using a PNG, you make an svg out the PNG, could import that to Blender and use it  in 3D space

There's also an auto-trace route within Blender, but easier to do outside..

You can import an svg and convert to mesh, if you do so ignore the first steps.
If you don't have any svg you can save your image as jpg or png with a white background and import it as Image > Reference, then Object > Convert > Trace Image to Grease Pencil:

Then RMB > Convert to > Bezier Curve:

The bezier object will overlap so move the original:

Select the bezier object and RMB > Convert to > Mesh:

Switch to Edit mode, select all and X > Limited Dissolve in order to simplify:

Also press M > Merge by Distance to merge all the overlapping vertices:

Fill the faces with AltF:

Then again do a Limited Dissolve in order to simplify the topology, now you can extrude:

If you plan to round the edges with bevels you'll need to work the topology of the faces a bit...


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BlenderGIS: Basemap is not rendering along with the object
I create an animation of camera around my object which is referenced on the basemap. When I try to render the animation or just the image, I only see the Blender object. What do I need to do make the basemap also part of it?
In this screenshot you can see how my Rendered results don't match the camera view

You have imported the image as a reference, which is basically an empty object displaying the image in the viewport. Empties will not be rendered. You have to put the image on a regular plane object.


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How To Align Verticles in Straight Line
I have this image with uneven ground. I'm struggling to even out these vertices, it should form an even ground and should look in a straight line because if I try to align it on a base plane, it looks very wrong and I see gaps etc.
I"ve tried using G option and then tried to move vertices but it distorts other part of the model. What are my options here?

The easiest way to align vertices I can think of is to select all those you want to flatten, then scale them by 0. For example s > z > 0 key combination will flatten all your vertices along the global z to their centre of mass, and you can move things after that.

However it looks like what you have there is a point cloud, and in doing any editing of the vertices you'll get texture stretching (which may or may not be okay).
You could try using Sculpt Mode and the Smooth brush, but I'm not sure if that's the result you're looking for.
Note: If G to move vertices is moving other parts of the model make sure proportional editing is off (Shortcut for that is the letter o)


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Making a scratch with parameters to tune on my image texture background
Sorry for the stupid question.
I am a new user in Blender.
I am trying to make a plane with only one scratch on it, and I want to set some parameters such as width, length and depth for later tuning. I have my own image texture for the plane's background. However, I can't generate the scratch on it properly. Honestly, I even can't generate scratch on it with procedurally way. I want to make it all with script so that I could make it automatically later. Please give me a hand, I have try it two weeks without any progress. Thanks a lot.
This is what I want.


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Blender 4 Python Scripting issue: Pyodbc module not found error
I am a Python noob, trying to make a small script to facilitate the application of materials to a large number of small models making up machines for the company I work for. The script in general works and loads a dictionary from a .txt file containing key, value pairs which reference model names, material names. The higher ups want this to be changed to reading from an sql server table.
While writing said server integration of the blender script I ran into the error:
Python: Traceback (most recent call last):
File "", line 1027, in _find_and_load
File "", line 1004, in _find_and_load_unlocked
ModuleNotFoundError: No module named 'pyodbc'
I have looked around and not found a solution to this issue, I have seen this module be recommended for sql server integration on a few site with other libraries referenced for other server types.
I have only one non default setting applied: Material Library VX which is integral to the function of this script.
Anyone have any idea why Blender scripting would be having this error?

You have to install pip and then install the module pyodbc using pip. https://blender.stackexchange.com/a/283142/142292

would that be somehow inside of the blender console? I tried it in the cmd like it recommends to do online but no change, then tried updating pyodbc but same result.


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Render and preview give different results
That is, it turns out that when rendering shows one picture and when working another.
At the same time it will be saved as in rendering, the element will be stretched along one of the axes for some reason.... Any guesses about what causes this and how I can get rid of it
Render result. -
Viewport

Hello please showyour whole Blender interface, maybe even share your file, maybe you have enabled some option for render that are not enabled for preview?

Update.
@moonboots

Sizing - All good
I make Subdivision Surface + Subdivide mesh in Edit mode - All good
Make hole with Loop Tool - All good
Ctrl + A - All broken

Why Ctrl + A crash all?
And I don't know how I can share file here

Too hard to tell, please share your file, use https://blend-exchange.com/ (read the instructions) or use another platform like workupload

@moonboots
First before Ctrl + A (All transforms)
Second After

You are now showing another problem, the problem in the object you share is that you've keyframed it with a Scale of 1:0.175:1, if you apply the scale it will consider this dimension as the new 1:1:1 but as the keyframe is still here it will squeeze again on Y

Thank you very much

The problem in the object you share is that you've keyframed it with a Scale of 1:0.175:1, if you apply the scale it will consider this dimension as the new 1:1:1 but as the keyframe is still here it will squeeze again on Y, so if you don't need this keyframe, just delete it:

Merci beaucoup!


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When having two array modifiers on an object, is it possible to two modifiers ignore each other?

I am a beginner to blender and want to have two array modifiers on one object, with the goal of creating a square outline (out of cubes). My issue is that two array modifiers on one object recognize the other modifier, and it leaves me with this filled in grid instead of two solid lines. Is there a workaround around this or should I simply just duplicate a singular array

Hi Sofie, would you please add an example image of what result you want? I am not sure exactly what you want to accomplish yet, but I think you want to create a frame out of cubes?

No but you can probably do it with geonodes

@CobyRandal it probably refers to this question. It contains a picture of the desired result: https://blender.stackexchange.com/q/314522/107598

Update:
easier with this:

it's as easy as this with geometry nodes:

first we create a grid, with 4 vertices. Then we delete the inner face of that grid. We split the edges so that we get 4 curves by mesh to curves. These curves we can give an exact amount of vertices by resample curve. Then we just instance points on that curves.
the curve to mesh and merge by distance is necessary, so that we don't get double points/cubes on the edge points.

If the two lines surrounded in red have same length, you can mirror:

Use an empty as mirror object and rotate it 45°.
Weld after that as two cubes are overlapping.

In order to have all the surrounding edges, you can place the empty (rotated 45°) at the center of the square and mirror on X and Y.

There are very likely better/ easier ways of doing this, but this works.
Make your array on the X axis and apply the modifier after you're satisfied with the way it appears. I used the settings as shown for the X axis in the image in your question.
Press Shift->D to duplicate the object and before pressing any other key press R -90 (that's minus 90) to rotate the duplicate to align with the Y axis:

Select both objects and press Ctrl->J to join them. In Edit mode select everything and then select Merge By Distance to remove overlapping geometry:

In Object mode press Shift->D to duplicate your new object. This time before pressing any other key, press R 180:

I'm using version 4.0.2 of Blender and it has a new snapping feature. With vertex snapping turned on and your mouse near the bottom end vertex of the new object, press G and then press B and drag the corner to the end of the Y axis so that it snaps like this:

Then join the two objects together with Ctrl->J. In Edit mode select everything and Merge By Distance. You end up with this:


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How to fix my cloth behaving wierdly?
I use cloth simulations for a short time and now I have second issue with them (in the same project). This time when I made a test animation of my character lowering its arm and the cloth started to break in various ways: it accumulates on both sides, it rips apart (I use sewing) and so on...

Please help! Here's the file:

Is this a dummy or the actual model to animate? I wonder because it has a rather messy topology. Blender's sewing does not merge the mesh parts automatically, but you can collapse the sewing edges manually.

This is a model, that I want to animate. Yeah, the typology is not great, but it's because I'm not experienced enough. Anyways, thanks for an answer. I'll try to make the edges manually.


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How to Export JSON from Blender with Split Normals using Geometry Nodes
I am trying to export a JSON file from Blender and need split normals as data on vertices. I have exported a custom attribute named "norm" using geometry nodes. However, I am struggling to evaluate the graph while looping over the primitives of the geometry and appending that in normal list.
Here is my for loop block:
    h_index_to_out = {}

indices = []
positions = []
normals = []
colors = []

index = 0
for prim in bmesh_car.faces:
    for vert in prim.verts:
        h_index = vert.index
        if h_index not in h_index_to_out:
            h_index_to_out[h_index] = index
            index = index + 1
            pos = vert.co
            positions.append(pos.x)
            positions.append(pos.y)
            positions.append(pos.z)
            **#At this point I need to write that custom exported attribute on vertices**
            normal = vert.normal
            normals.append(normal.x)
            normals.append(normal.y)
            normals.append(normal.z)

            colors.append(1.0)
            colors.append(1.0)
            colors.append(1.0)

        out_index = h_index_to_out[h_index]
        indices.append(out_index)

How can I properly evaluate the geometry nodes graph to access the custom attribute "norm" and correctly export the split normals along with the vertices?
Any guidance or examples would be greatly appreciated!

Welcome to BSE! I'm sure someone will help, but first I suggest you prepare some minimal working example: How to upload a blend file on BSE - good practices and advice, also put a screenshot of your geometry nodes in the question. Possibly a duplicate of How to get the mapping of face(vertex) index after applying geometry modifier? except there I'm reading face attribute, not vertex/corner.


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Scaling different parts of a model differently
recently I have been trying to print models of steel buildings using just I beams. I start by downloading a file of one and then scale them way down to fit the print bed. But when I scale them down to a printable size (anywhere from 1 to.1 percent of the original model) a lot of the walls are too skinny to show up after slicing. I want to be able to thicken the web and flanges without changing the length of the beam. What is a good way to accomplish this? I thought I could scale the beams along the axis that thicken the web(center) and the axis to make the top and bottom I thicker but I couldn't find a way to do this efficiently after googling for some time. Is there a good way to be able to select multiple parts and scale them on 2 axes, then select other beams to use different axes? Or am I going about it the wrong way? I am using bamboo studio as a slicer and trying to print on the x1 carbon.

What you can't can't be done by scaling the object itself. You need to go into edit mode and manipulate the faces themselves to achieve that. If you select one or more faces in edit mode, and press alt+S, you can move them along the normal, i.e. it would thicken the part.
Can you show a picture of the beam? Depending on what detail they have you might be better off creating an actual object that can adjusted quickly from scratch than manipulating an existing one


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Arrowhead line animation
I want to make an arrow-marked path animation. I made an arrow, and I know the path animation method, but I have a problem. I want the arrow to follow a visible path to the target after leaving the starting point. I couldn't find a way to do this.
I did it with Grease Pencil, but I didn't like this method. I also tried the object-following-path method. But I wasn't satisfied with these. How can I make an arrow movement on a plane/map in 3D as seen in the image?

Create a segment (1), and its start and end tips (2 and 3):

Give it an Array modifier with object 2 and 3 as Cap Start and Cap End:

Give it a Curve modifier:

Animate the Offset value of the Array to make the arrow get longer:

I am doing all of them but the tip of the arrow and the cover part (2 and 3) do not fit into the front and back of cube number 1. They fit sideways. How can I place pieces number 2 and 3 neatly in front and back of cube number 1?

Select the front object, switch to Edit mode, move the mesh so that it sticks to the segment

''Fixed Count'' didn't respond. So i tired ''fit curve'' and this time it goes straight. It doesn't follow the road.

could you please share your file?


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Baking makes repetitive patterns
I am struggling to bake a material that I can then export into software for game creation. Whenever I bake my texture, the baked texture is completely uniform - baking removes the randomness of the pattern created by the normals texture. The color of the material bakes perfectly fine, just not the normals.
I assume this is because my UV map looks like only one rectangle in the photo below. I don't know anything about UV maps, could someone tell me where I could look to make my UV map encompass the whole object or is there something else I should be doing to prevent this uniformness?
Thanks!

Bake settings and textures

Hello probably your unwrap is incorrect, check the UV Editor

It looks like you have one box object somehow instances to form a row of boxes (or duplicates but sharing the exact same UV space), and your material maps the texture across instances?
If so, what you see is normal. Your instances all share the exact same UV space. Hence once the textures are baked as per the UV, all differences across instances go away.
If you want to avoid that in baking, you need to turn these instances into real objects and edit their UVs to not overlap.
The way to do so dependa on how you made it in the first place, so please [edit] your question to explain it if you need further help.


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How to make a mosaic path and question about names of textures
I am new to blender and I was wondering how I would go about making a Stone mosaic pathway that looks something like this . I am not sure if I can get away with using a bunch of arrays or if I would have to hand-place a bunch of the blocks seeming as there are a variety of shapes that may be hard to repeat.
Also is there a term for materials that are not super detailed? I wanted to create materials for a cartoon game I am coding in Java but I feel as though I can only find super detailed procedural textures.
Thanks!

This particular mosaic isn't very exact-- there's a lot of randomness.  For the geometric stuff, I would start with geometric solutions (like an array but maybe other things) and then randomize it.  For the rocks, I would boolean to make the cutout of the circle, then use cell fracture addon to randomly divide it, and then further randomize it.

about the "bonus question": I guess you are looking for baked textures or texture baking. The baked images are not procedural & are used in games and to speed up render time at the expense of detail when you zoom in very close.


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What rigify bones should I map a mocap .bvh armature onto for retargeting?
I am trying to write a script that retargets a mocap .bvh file onto my rigify armature. Ideally I would just rename the bones in the .bvh armature to match my rig and change the action in the action editor. I'm not sure which bone names to use though. It doesn't seem to work if I just map every bone onto its ORG- counterpart bone.
If I apply constraints to the joints and bake the animation, it only works if I clear the rigify constraints first. I'd like to keep those in tact for animating later scenes. Here's a portion of my code:
    bone_mapping = create_bone_mapping() # This is a dict of the .bvh bone names and their corresponding rigify ORG- bone names. e.g. "Spine": "ORG-spine.001"
    original_constraints = store_constraints(rigify_armature) # Goes through each bone in the armature and stores the constraint in an object that is returned
    set_constraints(bvh_armature, rigify_armature, bone_mapping) # Set rotation constraints to my rigify rig to follow the bvh rig
    bpy.ops.nla.bake(
        frame_start=bpy.context.scene.frame_start,
        frame_end=bpy.context.scene.frame_end,
        only_selected=False,
        visual_keying=True,
        clear_constraints=True,
        use_current_action=True,
        clean_curves=True,
        bake_types={'POSE'}
    )
    remove_constraints(rigify_armature, bone_mapping) # Deletes the bvh constraint I added above
    re_add_original_constraints(rigify_armature, original_constraints) # Re-attaches the original rigify constraints. Everything works fine if I comment this line out

I either need to know how to rename the .bvh bone names better so I can just change the action, or know how to update the script to bake the animation and keep the constraints.

I think I found a solution. The mapping is a bit messy. Mostly mapping to the fk bones and a few original bones. https://bitbucket.org/Diffeomorphic/retarget_bvh/src/407a1ab5758dd9a05de3badc250781a65141ac77/known_rigs/rigify4.json#lines-6


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MTREE Export to Unreal Engine 5
I am using MTREE for creating trees for a game and I wanna export these tree to unreal engine 5. But I can only export the tree itself without the leaves because it is not part of the Mesh. How can I fix this or how can I add them to the Mesh, because there is also no layer for the leaves in my collection.

Did you try joining the tree and the leaves with Ctrl+J ?

Thats not possible because there is no layer for the leaves. It is just one layer/mesh (the original mesh (cube)) with the three and the leaves but the leaves are somehow not part of the mesh

I'm not sure what you mean by layers. Please add to your original post screenshots and your blend file with https://blend-exchange.com/.


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The load factory settings isn't working
Recently, i have modified my startup layout like the change in measurements of unit and grid etc. Then i saved it as startup file.
now when i reset it to factory settings it changes to factory layout, but when i open a new file it again becomes the customized one.

i came across a solution just now.
What if i load it to factory settings and then save it to startup file.
it worked out, My issue is solved.


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Any way to save object properties to the asset?
I am trying to make myself an asset library system which includes a lot of technical objects like collision boxes, triggers e.t.c. (basically I am using blender as a level editor for an educational project).
I have picked a nice blueish semi-transparent color for collision boxes, which, if set as an Object->Viewport Display->Color allows for a pretty semi-transparent box preview in the viewport mode (if color is set to "Object" in the Viewport Shading tab, of course).
But the problem is that when I save the asset and use it (making sure I save and refresh everything and set the correct color mode before testing) all object properties are getting flushed, which leaves copied instances of the box with default ligh-grey opaque object color.
Is there any way to save the object color to the asset in order to get the preview I want?
I have already tried using color attributes, but their transparency gets ignored. At least they transition to other instances of the asset, which is good, I guess.
I can assume that the reason behind this is that only the data of the object is getting saved to the asset, which makes sense, but could there be a way around this limitation?
Thanks in advance to anyone willing to answer to this question.

As it turns out, blender saves object properties only if the object itself is an asset. If the object is a part of a collection that is marked as asset, object properties inside the collection get ignored.


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How can I get the light direction vector without the roll values?
From watching videos and looking at other posts, it seems like the common way is to just straight up copy the sun's rotation values for the light direction vector. However, this also copies the roll (local z rotation) value, which it shouldn't, considering directional lights are spherical. As a result, N Dot L will change if you rotate the sun on its local z axis, which doesn't make sense. The regular diffuse shading models that the BSDF nodes use don't take the sun's roll into account, so what are they doing differently?

I may not have understand properly, but you could use the rotation vector you are talking about (which include z rot) to rotate à vector (I think (0,0,-1) In your case). You would get a direction vector instead of rotation vector, without any local z rotation.

@Lutzi That actually works perfectly, thank you. Now I'm surprised I couldn't figure that out sooner


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What's the significance of the number ~158.9942 in this scenario?
I was trying to create texture coordinates for a cubemap and in order to get the right masking factor for each of the faces I needed to use the geometry's normal. Dividing the absolute value of the normal by the sum of its components gets me close, but the result is basically rotated 45 degrees from what I'm expecting. I tried a lot of ways to rotate it and settled on exponentiating it until it was close enough.

The weird thing is that, at the corners of the result, the value 158.9942 gives a near-perfect point, where any value above or below 158.9942 seems to "clip" off the corner

...so what's up with this number? I was thinking maybe the decimal is related to sqrt(2) = 1.414 but I can't zoom in any further to verify if 158.99414 is any closer. But that also doesn't explain the 158.99, so is there something I'm missing?


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Can't Find My Entire Project
I spent a lot of time making a project & can't find it today. I've tried searching for it in the finder with .blend
I remember saving it & see something like looks like the project but it's a document file and I get the warning when I try to open it: There is no application set to open the document “title.blend1”.
My other question is - there was a point when my MacBook shutdown unexpectedly - if so does it recover blender files. Trying to connect the dots and hopefully find my beloved project. Thanks in advance!

.Blend1 files are backup Blender files. If you go to File > Open... in Blender the File View dialog has a filter icon top-right. Click the down arrow beside it and and you can check the Backup .blend Files option on the list of file types. You should then see the .blend1 file that you found and it should open in Blender just like a normal Blend file. However, it will only have the contents from the last time you successfully saved your file.

You could also try File > Recover > Auto Save.. but that will depend on your settings under Preferences.


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export stl file doesn't show image plane shrinkwrap
I'm new to blender. I wanted to put different pictures on my object. So what I did was import image as plane. Then shrinkwrap it to 1 surface of the square.

Then I export it as an stl file. The problem is when I view the stl file, the image isn't on it. And yes, I've check all 6 surfaces of the cube.

Am I doing something wrong? Thanks!

Of course there is no image. STL files have no materials, no modifiers, no multiple objects...


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Tissue rotation wrong
I'm new to blender, and I'm trying to use the Tissue add-on to create a pattern on a surface. The command Tessellate itself is pretty straightforward to use, but I get a strange rotation of the pattern in some points of my mesh, and I don't get why. Can you help? Here is a picture of the problem:

I just want the tiles to be all in the same direction, upwards.

Please share your Blend file so that we can 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.

No need to share the blend file, of course there are ways to change the rotation of the tessellated tiles.

I guess you have extruded the object downwards or something like that? When you do that, it could be that the orientation of the new faces is different from the existing faces. And I do not mean backfaces pointing outwards, but the way the vertex indices are distributed (well but honestly I do not know which information is responsible for the rotation).
When you are adding tessellation, the new "Tessellation" object that is created has some more settings in the Object Data Properties tab. One of them is Rotation:

There are different options, the Default is naturally chosen. You could now for example choose Active UV and in case in the original object all faces had their UVs oriented in the same direction, so will the pattern be:

In my mesh this leads to all "arrows" pointing to the right though. To correct this, I can change the Shift value until all point upwards:

The important thing for this to work is: the UVs have to be correct on the original object before tessellation. Changes afterwards will not be incorporated. Also you cannot change the UV map on the tessellation object, this will have no effect either.
And here is an example how to use the Weight Gradient option:
When you paint a gradient on the original object like this, it automatically creates a vertex group called "Group" to store the weights.

Now you use the Tissue tool again, and in the Rotation settings of the "Tessellation" object you can now choose Weight Gradient and the Vertex Group called "Group" which was created in the original object. The arrows are pointing to the side but I can change this by Shift of course.

Or I could have painted the weight in a different direction right away:

But again, this has to be done on the original object before tessellation. Later changes will not be taken into account. Of course this can also vary from the orientation of the pattern which you are placing on the object.
That's just a "quick" overview, I'm not about to post a complete tutorial on the Tessellate tool. There are a lot more settings, but to get the pattern somehow aligned this should be helpful information.
//EDIT: Okay, one more short example how you can use weight painting for creating patterns. Here I selected every second horizontal edge loop, then added a vertex group and assigned those edges with a weight of 1. Then I used the weight paint group in the Tessellation with Weight Gradient and got this resulting pattern where the arrows are alternatingly changing directions:

Thank you, this seems to work!


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When converting simulation to mesh, is there any way to use less particles?
I am wondering if there is a feature in blender that allows you to control the number of particles you use to bake mesh.
The thing is, I'm making very thin stream of water pouring down using fluid simulation but there are always tiny splashes happening around the stream (even though it's not hitting anything) and I don't want to convert those extra bits to mesh.
Cranking up the resolution division in Physics tab and making inflow object smaller might be a solution but I can't set more resolution due to machine spec limitation, so I was wondering if there is other way.

Say for example, a feature that lets you ignore particles groups that are less dense.


text:
Unintended lines appeared during retopology work
I was working on a retopology of a character in Blender. After applying multires and shrinkwrap, I noticed that I had an unintended surface connecting my thumb and index finger. It is not visible in Edit mode, but only in Object mode. It seems trivial from afar, so I ignored it for now, but I would like to know why this problem occurs because I think it may affect future texture work or animation.

Looks like a glitch in the Multires modifier data. Have you tried "painting over" the area with the Multires Displacement Eraser brush? Related questions: https://blender.stackexchange.com/q/278332/107598, https://blender.stackexchange.com/q/214280/107598 and https://blender.stackexchange.com/q/242710/107598


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Random Value GeoNode on Mesh Line Node parameters
Im trying to instance a mesh line on each vert of a grid.
But id like to randomize the length or count(resolution?) attribute of each individual mesh line (because ill instance a stack of objects on each mesh line point). The randomize node works with scale/position on a transform node in the tree. But Id really like to use it on the count, end point vector, or resolution of the specific mesh line node. I kinda got a noise node to work but its randomizing the end point of all mesh lines instances by the same amount. anything else with a random value node will create a red line inbetween the sockets. So is this possible?

this is not possible with instancing because instances cannot be changed as you want it (that's what's the diamonds and (filled)circles are for, you cannot connect those). But i am convinced it is possible with GN with clever math and some realize instances and lots of thinking ;) or short: you cannot change instances per instance. Just afterwards ...(after the instance on points)

@Chris just stomped on another one of my answers ;) .. As he says, the key is: use Curve Lines instead of Mesh Lines, because they can be resampled.

ok, i figured it out how you can do it:

result:

The main idea was: just move the upper vertices of the curves randomly by noise, then subdivide the curves depending on their height. That's it.

thanks! im not sure if ive got it working though. still trying to wrap my head around it. The curve node on the right, which i think youve renamed?, is that Resample Curve? if it is, mine doesnt have a selection socket. maybe a different blender version?
also, im working in smaller units, mm, so if i wanted to scale this down, which nodes should i and should i not touch to avoid breaking it. I tried a bit and at a certain size it seems a lot of it gets clamped or something.

yes, i am working on 3.1. And yes, it is a resample curve node. Did you set it to length? that's important. And yes, you should have written that in your question if you use a specific blender version, so i was assuming you used the newest.

sorry, i am using 3.0, sometimes i forget how many more features are in alpha versions. i did set it to length. Switching to alpha and fixing another node make the version you made work great. Now im just trying to figure out a way to shrink it to a smaller scale. Im essentially trying to have a true-to-scale stack of poker chips. changing some of the nodes past a certain point seems to break it. While the smallest i can make it without breaking, each column height will jump in segments of what look like whole grid units, instead of smaller increments. https://i.imgur.com/bCh0fdy.jpg


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Why does this happen when I try to add a uv sphere?
When I try to add a UV Sphere it adds 2 different spheres:

The outer weird-looking sphere is somehow linked with my icing and when I select the icing the outer sphere gets selected too (when i delete the sphere the icing gets deleted too):

Can you post screenshots with the Outliner? I think you have an instance of collection.

I'm not sure why you get two spheres when adding one, but the weird sphere "linked" with your icing sounds like you've added the sphere while you were in Edit Mode on the icing. Adding meshes with Shift+A doesn't necessarily create complete new objects, if you add something in Edit Mode it becomes part of the object you were editing at the time.

I don't understand, I added a UV sphere in object mode and it still happens @GordonBrinkmann

This happens because the new UV Sphere you are creating is put inside the collection you created for different types of sprinkles.
So the donut is a tutorial by BlenderGuru and for the making the sprinkles randomly spread out on the Icing, Geometry Nodes were used. Now the objects to be used for the sprinkles are selected using Collection Info so putting the Sphere inside the Sprinkles collection makes it subject to the geometry nodes as well.

Just move the sphere out of the Sprinkles collection and you should be fine. And the next time you are adding a new mesh, make sure you select the collection where you want the mesh to be put in.


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Remove certain lines of stroke/line art modifier
I want to make a 3D model look more like an anime picture, so I added a grease pencil stroke and added it to the collection with the modifier. Now it almost looks good, but some lines I dont want, like the lines on the nose and neck. How can I get rid of those? I tried looking for an editor for the stroke but there isnt one to my knowledge.
Attached is an image of the model and render.

Don't know the specifics, but it looks similar to when you have the auto smooth turned on in the Normals tab within the Object Data Properties while using the line art modifier. To keep the good line art mixed with the good shading, just bake the line art , and then turn on the auto smooth


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Blender doesn't work on a server
I have a server with Linux installed on it. I also installed Blender with apt install blender and I want to start a render on it with blender -b <file.blend> -a but it returns those errors :

Do you know how to fix that ?
Thank you very much.

I found a solution. Those errors are related to the sound card and my server doesn't ahve one. So the solution is to disable sound with :
blender -noaudio -b


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Cannot import nested Python module when writing an add-on
I am working on my first add-on, though I am pretty experienced with Python having written multiple apps using Django. My project structure looks like this:
lib/
  application/
  blender/
    models/
    operators/
      test_local_simulation_operator.py
      ...
    ui/
      panels/
        test_simulation_panel.py
        ...
  domain/
  ...
__init__.py
...

My init file contains the following code after the bl_info.
from bpy.utils import register_classes_factory

from lib.blender.operators.test_local_simulation_operator import (
    TestLocalSimulationOperator,
)
from lib.blender.ui.panels.test_simulation_panel import TestSimulationPanel

classes = (TestLocalSimulationOperator, TestSimulationPanel)

register, unregister = register_classes_factory(classes)

I am using VS Code on Windows with the Blender Development extension. When I launch the add-on using the Blender: Start command, I get the following import error:
Traceback (most recent call last):
  File "c:\Users\[user]\Blender Foundation\Blender 2.91\2.91\scripts\modules\addon_utils.py", line 351, in enable
    mod = __import__(module_name)
  File "C:\Users\[user]\AppData\Roaming\Blender Foundation\Blender\2.91\scripts\addons\[project_folder]\__init__.py", line 22, in <module>
    from lib.blender.operators.test_local_simulation_operator import (
ModuleNotFoundError: No module named 'lib.blender'

I have tried adding an init file to all of my sub-modules to no avail. The only way I can get it to work is by adding this import style to each init file chained throughout my project.
# lib/__init__.py
from . import blender, ...

This seems like a lot of unnecessary overhead not required in conventional Python projects, so my conclusion is that I am doing something wrong here.
What should I do to get my modules to import properly?

See this. Everyone just writes from . import though. You can always check how the default addons do things.

(Not using VS) but suggest looking at answers here https://blender.stackexchange.com/questions/158775/having-trouble-creating-an-addon-with-multiple-modules and similarly here https://blender.stackexchange.com/questions/183773/trying-to-make-a-menu-using-multiple-modules/183817#183817   Rather than some horrible long import chain to get a blender class to register,  can propagate the register down the hierarchy by calling the register method of immediate child modules.

Thank you for the comments! I was able to solve it by diving down the rabbit hole provided by @scurest. I created a function to register my add-on path with Blender's paths, moved my class imports to a getter function, and called these from my own register/unregister functions instead of using Blender's factory utility.


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Animation glitching in Eevee render
I'm having this weird glitch in the animation when it's rendered by Eevee.
Here's the render:
https://www.youtube.com/watch?v=UQp_8KcGCjo
Notice how the animation of the model glitches and rotates randomly at certain frames.
I've picked frame 3 to better visualize the issue.
Here's an Eevee render of frame 3:

And a Cycles render of the same frame (issue is not presenting):

I've tried to set the sampling number to a higher value without success.
After many renders and tweaks, I believe it's related to the motion blur, however, I can't figure what's causing it. Tried to add more steps to motion blur but the issue remains.
Any idea of how I can solve this?
Thanks

Hello, how is your object position keyframed ? These glitches can come from objects that move quite far from one frame to the other, throwing off the motion blur algorithm

The model itself doesn't move in a axis, it remains on place while the running animation is played - the fast moving part is actualy the scenario, which is an array of a cube.There are no objects that move very far from one frame to the other.

Got an idea... maybe it's related to the cyclic motion I made using nonlinear animation? Even though it doesn't show the bug in the viewport (model motion plays without random rotation issues).

Hard to tell without the settings in front of me ^^ But it seems smart to dig in this direction. There might be optimisations in the viewport that prevent the glitch to appear


text:
How to render 3 different scenes in one shot?
I have 3 scenes in my file, one with the background in 24fps rendering and the camera moving, another with the animated characters rendered in 12 fps, another with just the shadow of my character. I would like to render my 3 scenes separately, in 3 different folders to recomposition the whole in the video editing but I need to render my scene one by one. How can I render 3 different scenes by only throwing the rendering once?

Add another scene, switch to the compositor workspace - add 3 different render layer nodes to the compositor and use one or multiple file output node(s) depending on how the output should be.

Does this answer your question? How do I batch render multiple scenes with animation settings?

Yes and no because the problem is that the rendering continues after the end of the 12fps animation rendering because the 24fps is longer. Do you know if there’s an alternative to that?

Either render the 12fps shot(s) seperatly, save a new blend file containing equal frame rates and render it on another machine or just use the command line: https://blender.stackexchange.com/questions/313/is-there-a-way-to-batch-render-multiple-scenes ... hundreds of possibilities depending on your setup.

The answer corresponds to my expectations thank you!


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Eevee, lighting, Volumetric lighting crosses a mesh
I created two light spots with volumetric to get a beam of light with eevee in a real-scale scene. My light passes through my luster mesh despite having turned the shadow mode to none for the various shaders. If I activate the volumetric shadow I get a kind of sphere that hides my light in relation to the emission distance. If I mount the volumetric shadow samples, I end up completely losing my light beam. I have already tried to lower my light below the mesh but I always get the same result (for example in top view my light passes through my meshs to the rendering. How can I get this lighting visually, without my light passing through my mesh at rendering?


text:
How do I move an object using the script editor?
I have looked for a while and cannot find an answer to this simple question: What code do I write to make a cube go from anywhere to anywhere? I have a spaceship that I want a player to be able to move and rotate using keys. How would I do this? Is there a simple way to make the ship move to anywhere I have not found yet?

That's not possible anymore since the game engine has been removed. You would have to use a game engine like godot, unity or unreal with dedicated player controls for that.

that explains a few things

How to set the location (without player control): https://blender.stackexchange.com/questions/39451/cant-set-the-location-of-the-object-by-program


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Cannot sculpt on a mesh after cloth simulation
I have an issue with this mesh where I made a cloth sim on a character that I want to smooth and tweak a bit but for some reason I cannot sculpt anything on it. I have shape keys, I tried with and without the subsurf modifier. I tried with the multires. I tried without any modifier after the cloth sim. Nothing. It's like it's stuck.
I am certainly missing something. I did cloth sims in the past and was able to sculpt afterwards with no problem.
I have the blend file here for who has a bit of time to help me.
Thank you!

Have you applied the cloth modifier after the simulation?

No, but I just tried and weirdly enough it messes up all the cloth when I apply it.

Got it...it was the armature (I binded the cloth to the armature of the character and it gave an armature modifier to it as well and it was messing the mesh up when applying the cloth modifier). Now I can sculpt on it!

The cloth modifier needs to be applied in order to sculpt the simulated mesh. If there is an armature modifier before it in the stack, it needs to be applied as well!


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Human mesh with complex hair particles posing
I have a human mesh with lots of hair particles that I would like to pose and use the posing animation to set a cloth simulation so the clothing sits realistically1 in the pose position.
When I pose with all the hair connected Blender slows a lot and the clothing animation is kind of out of the question. So I disconnected all the hair particles to do the pose, than the clothing, than the animation (cloth simulation included). But when I reconnect the hair they obviously go haywire because all coordinates changed.(ctr A all transforms didn't help) Any ideas, solutions, better process to obtain the desired result?

Are the particles hair modifiers after (under) the armature modifier in the modifiers stack?

Yes, the order is 1. Autorigpro created rig 2. Collision modifier(for the cloth) 3 to 12 particle systems

Did you try not to disconnect particles, but turn off their visibility (screen icon) only?

I discovered one of the main problems in the meantime. When using Autorigpro, for some reason I don’t understand, the vertex groups are deleted and replaced with new ones generated by Autorig. I suppose it has to do with the parenting of the bones. So I’ll try to save two instances of the same file. One before rigging and one after; then copy the vertex groups from the unrigged one to the rigged one and see how that goes.

ok so copying the vertex groups breaks the pose and cancels the rig parenting somehow, so not an option.


text:
remesh or retoplogy, maybe specific tool?
Still a beginner here. I have this cloth pattern and I cannot seem to find a good way to automatically obtain a good topology on it. Anyone knows of a good method for this case?(screenshot attached) I tried remesh but it only gives me very weird shapes. I used knife tool and proportional editing to get to this stage of deformations. I would really appreciate any advice!

What constitutes "good" topology changes from one end-use to the next, and can be sufficiently opinion-based for this to be an inappropriate question here.  My fave topology links are over here: https://blenderartists.org/t/topology-understanding-and-poles/1248035/3 .  For this ask, editing it to add more details on what you intend to do with that could be helpful.  Also, it's often a good idea to post your blend file, or a truncated version of it that includes the issue.  The Blender StackExchange has its own service to share blend files:  https://blend-exchange.com/help

This is one example of a “good” (all-quads, no poles less than 3 or greater than 5, no poles on creased or tightly curved areas, even polygon distribution, loops [shown in blue and orange] follow real-world function) for a garment similiar to what your screenshot shows:

With its included add-ons F2, Loop Tools, and Bsurfaces GPL Edition enabled Blender is sufficient for general (but not automatic) topology and retopology needs.  Recommendations for external or commercial add-ons can run afoul of BSE's rule against opinion-based questions and answers, but this topic at BlenderArtists may be helpful.

Thank you everyone for your answers! Very much appreciated !

Hope it was helpful!  If I've answered your question then please click the checkmark next to my answer.


text:
Downloaded rigged blender mesh, oversized bones
I downloaded a blender file which was supposed to include rig, animation, textures etc.
But when opening it I got the rig oversized and it seems that if I scale it, it scales the mesh too. Anyone knows a process to make this rig useable? I only need it to pose, I'm not doing animation.
Thank you!

Scale  rig in edit mode?

From the screenshot, it looks like the bones' heads (roots) are at the right place, but only their tails (tips) are somehow far away.
This looks like a rig from an external program that has been badly imported to Blender. Some programs don't have notions of start points and end points for bones, they are just unique points. That's why sometimes you have "leaf bones", to serve as visual endpoint for bones.
But when you import such rig with no tail to Blender, you need to recreate these tails somehow, and one solution for that is to just create each bone's tail at an arbitrary fixed distance from the head.
Theoretically, as long as the bones heads are in the right place, the tails locations doesn't impact how the rig functions, it's just visually unpleasing.
To fix that:
In edit mode, select all bones. Set your Transformation Orientation to Local, and your Transform Pivot Point to Individual.
Then scale your bones on their local Y axes by pressing SY.

There are also scripts that can snap the parent bone tail to the child head, but that can break your rig if you don't know what you are doing. (and the one in my link is outdated.)

Where is that .blend from? I know some websites sometimes offer files that are generated by a conversion program rather by the artist who made the asset, be careful it's not that.

Thank you @LoLock for the detailed answer. It worked partially. What I mean by that is the selection on all the bones didn't affect the transformation of all of them in the same time so I had to do it one by one, but it's still a good solution. On the other hand scaling by Y was only moving the bones on the Y direction(same with any other axes) so I found in the Item proprieties (N shortcut) a bunch of transform options for the Head (X, Y,Z, Radius) and for the Tail ( X, Y, Z, Radius, Roll, Length, Envelope). The length was 100 for all of them and I input 2 for each bone.

I downloaded many assets a few days ago from multiple sites so I don't remember exactly the site where it was this one but I check each file for malware before opening and I only use them for my learning process so even if the sources are a bit obscure there shouldn't be any issue besides these details that I encounter and help me understand blender's functionality better.


text:
join head to body
I have this situation here where I want to join this Face Builder created head to a Human Generator body.
I deleted the HG head and joined the head mesh to the body mesh but now I want to fill the remaining gap with good topology. I managed to do this in the past with ALT F and it worked quite well. After that I used some smoothing and sculpting, dissolved some vertices and it was quite all right for what I needed.
But in this case when I use Alt F it only fills half the gap and I was wondering if there is a better workflow here than counting vertices and match them manually.
I added the blend file for reference if needed.
Thank you !

The best would be to have a consistent topology, between the body and head. But from what you have you could activate the LoopTools addon, remove the 2 first edge loops of the head, select the edges of the body and head and right click > LoopTools > Bridge:

Add some segments in the Operator box:

Result:

Thank you @moonboots! I forgot about looptools.


text:
Render objects without lights
Is it possible to bypass lights with a custom material/shader so that the material/shader is rendered directly to pixels? What I'm looking to do would have the renderer simply evaluate the scene and then have the material implicitly sent to pixels.
Cheers,

You can directly connect a color value to the shader output (without any node from the shader category). You may need to change the Color Managment to Standard, to get the exact color value. Not sure.

https://blender.stackexchange.com/questions/8108/node-for-setting-render-colour-regardless-of-lighting/ https://blender.stackexchange.com/questions/21533/totally-white-shadeless-material-in-cycles/ https://blender.stackexchange.com/questions/5099/how-to-create-a-visible-material-that-does-not-emit-or-reflect-light/ https://blender.stackexchange.com/questions/131015/where-is-shadeless-material-option-for-blender-2-8/


text:
Solidify not working properly
i am trying to create a chair, i followed a tutorial for the modeling part, clicked a and then solidify, the problem is that it doesn't follow the chair shape correctly. As you can see, under the chair it remains flat. I'm a newbie on blender and don't know how to solve this problem.

Apply the scale in Object mode (Ctrl A)

Thank you sm it worked

https://blender.stackexchange.com/questions/253469/solidify-modifier-applies-uneven-thickness-why https://blender.stackexchange.com/questions/7298/why-is-it-important-to-apply-transformation-to-an-objects-data/

Your scale is not 1:1:1, you need to apply the scale in Object mode (CtrlA)


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Channels tab is missing in video sequencer
I am on Ubuntu LTS 20.04, and here is my blender version which i think is latest.

for some reason I am not able to get channels tab at the top left of video sequencer (there(mouse arrow) is not that tiny arrow to toggle the channels tab)

I don't know the Linux versions of Blender, but Blender 3.0.1 is a very old version! The current LTS (Long Term Support) version of Blender is 3.6.10 and the latest version is 4.0.2! This is the download page with links to Linux and LTS versions.

The manual from v3.0 doesn't seem different from here, so i reckon that an update would already be a big step forward. https://docs.blender.org/manual/en/3.0/editors/sequencer.html

Thanks to all I just updated it and it is working.


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How can I make an object with rigid body physics not return to the first keyframe when I try to animate it?
Does anyone know how I can make an object with rigid body physics not return to its point of origin keyframe when I want to disable its animation?
What happens is that I'm trying to animate a ball going to a soccer goal, I have no problems to fit the keyframes for the movement of the ball trajectory to the goal net, but at the time of applying their respective rigid body physics, begins to experience failures, since at the time of having to apply its inertia for gravity to take effect and lower it, after hitting the net, the ball returns to the position of the first keyframe.
I have tried with CTRL + A to see if it is a problem of transformations, I have also tried to place the origin to the geometry of the ball before starting to animate, but it does not work, the net of the soccer goal is with physics in passive mode, in mesh form and in deform. The ball is the active one, with sphere shape. With the animate and dynamics button activated. The rigid body world is activated for both objects, gravity is also activated. I would be very grateful if you could help me. Greetings.
Translated with DeepL.com (free version)

So you made your rigid body animation until a certain point, and if i understood you right, you then want to animate your rigid body "manually" again.
For that you just can bake your rigid body animation to keyframes.
Example: you have a rigid body animation until frame 100.
You want to animate it manually from frame 101.
Select your rigid body object. Object -> rigid body -> bake to keyframes (use 100 as end keyframe).
Note: the rigid body will be deleted from your object. Just add a new one to it afterwards, if you need it again.

First of all thank you because it worked and my object does not return to the point of origin by doing what you recommended!


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How do I make the corner puff up/round like the reference pic

how do i make the edges rounded?

.

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


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Issue with exporting Blender 4.0 file with texture for printing on J750
I am in desperate need of help for exporting my Blender file.
I have a design with texture, which I'm trying to export so that I can print it using Stratasys J750.
Ideally, I should be exporting it to a VRML file but that no longer seems to be an option for Blender 4.0.
Are there any suggestions on how to overcome this issue?

See .fbx export why there are no materials or textures!

It's pretty old now, but it might be worth reading https://blender.stackexchange.com/questions/74060/vrml-2-export-not-visible

@JohnEason Thank you so much!


text:
How to correct weird geometry after boolean?
I have created a mesh with boolean operations (bool tool) and I need to have it ready for 3d print. Now I've noticed some weird geometry happening but I cannot determine what it is. You can see in the screenshots that there are weird shadows in object mode but in edit mode it seems fine. I checked the normals...they appear to be on the outside. I tried remeshing and decimating but the result wasn't nice at all and I admit I probably don't master these tools very well. I attached the blend file here for reference.
I would appreciate any help or suggestion to be able to have this ready for print.
Thank you!
in edit mode

there's one face (white outline) that is overlapping 2 edges (in red). delete that face and fill it in with 3 new faces (in green outline). the third face though will become an N-gon. better if you split it up into more faces.

Thank you @Harry McKenzie!

you're welcome, glad i was able to help :)


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Black Lines connected with doors
I do not know how to get rid of these strange black lines in Blender. I tried several solutions but nothing solved the problem. These lines are connected with the doors. I got those doors from Archimesh. Can anyone please help me? Thank you a lot

it looks like children lines, are your object parented to an object?

How can I check it out?

select one of the objects, check in the Properties panel > Object > Relations, or check the Outliner, see if they are under another object. Maybe share your file: https://pasteall.org/blend/

Hello and welcome. Rather than take photos of your monitor post actual screenshots instead, see How to take a screenshot. Photos are harder to read, because we have to guess if we are looking at a external interference like reflections or smudges or Moiré patterns, hardware issues such as a malfunctioning display or connection, a software level bug or driver malfunction, or an or actual artifact or issue with the model itself.

Thank you very much. I’m new here so I really appreciate your advice.

@moonboots How can I share my file? Thank you very much

use https://pasteall.org/blend/ ... upload your file, copy the URL it will generate and paste it here

In the Viewport Overlays panel, turn off Relationship Lines


text:
Liquid simulation in small scale
I need to create water simulation in the scale of a Glass cup (domain = 10 cm)
When I run simulation in the Blenders default domain size (1m) it all goes nice, but when preparing the same simulation much smaller, the color spheres are too large, and simulation goes wrong.
Do you know where is the magic parameter to change the scale?

When you simulate a fluid, the Domain has a Particle System for the fluid particles. The Size of these particles you can change in the Particle System Properties under Viewport Display. The Size there is always in absolute dimensions, independent from the Domain's scale.

However I have to disappoint you: this is just the size they are displayed with, changing it will not change anything in your simulation.
The only thing that will make the simulation better is probably the Resolution Divisions of the Domain, because this is the "real" size of the fluid particles or voxels. The higher the resolution, the smaller the particles. The smaller they are, the less errors Blender makes in calculating if something is inside or outside of an Effector object.

But even then it might still not work, because the glass is probably too thin for quickly moving particles to "catch" them in the right moment before they went where they should not go. To help with that, you could increase the Sampling Substeps on either the Flow object, the Effector or both. I build a similar scene like you, but with 50 substeps it still was not perfect.

Or you could make the glass ridiculously thick, then there is less to no chance that fluid particles will make it to the outside. This thick glass you would use only for simulating, for rendering you would place a normal glass in the scene. But this would make problems if you want the liquid to flow over the brim of the glass of course.
And be aware, all of these settings can drastically increase the simulation baking time. In general you could say, the simulation works better with larger objects, so unfortunately simulating in (small) real-life sizes can be very frustrating.

Could you bake first and scale later?

@DanielMöller Yes, this would actually work. Although theoretically the simulations take dimensions into acount, i.e. a body of water filling up a tank with a volume of a cubic meter would be different then filling up a can with a volume of 1 liter. But since the simulation's behaviour is also dependent on the domain's Resolution Divisions you might get away with it. Just like in Hollywood a flood might be made with a smaller scale model - but there comes a point where you can see that the waves and splashes have a different size than they should actually have and it looks unrealistic.

@DanielMöller Oh, and not to forget, the dimensions taken into account are also gravity settings. If you scale something to a size of 1 m for simulation and scale it down to 10 cm later, a drop of water falling down 10 cm will take the time it needs to fall down 1 m. Sure you can compensate things like that with speed settings or changing the gravity, but it will not be the same as the real-life dimensions.


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Batch Add to Asset Browser
Is there a way to batch add objects/materials to the asset browser? I have a fair number of various assets that I'd love to add to take advantage of the new browser, but they're all individual blend files. At the moment, I'm having to open each one individually, mark as asset, close, repeat. It's very tedious and would appreciate a way to speed up this process. Any tips or workarounds?

Goody it just so happens that I have just finished coding such tool yesterday :)
How to use :
How to run a script
OR
How to install an add-on
Then,
Go to File > Import > Batch generate asset previews

Navigate to a folder containing your blend files. Validate. It will automatically scan all the child folders recursively and mark all the objects as assets, and generate custom previews for them. Be warned that it will take something like 2 seconds per file to generate the assets and previews. It is because the previews are not instantly generated, and the thread generating them must finish before closing the file.
Here's the code that you can run as a script or install as an add-on :
bl_info = {
    "name": "Batch Generate Asset Browser Previews ",
    "author": "Gorgious",
    "description": "Batch generate default previews for the Asset Browser from selected folder",
    "blender": (3, 0, 0),
    "version": (0, 0, 2),
    "location": "",
    "warning": "",
    "category": "Import-Export",
}

from pathlib import Path
import bpy
import functools
from bpy_extras.io_utils import ImportHelper
from bpy.props import StringProperty
from bpy.types import Operator

INTERVAL = 1.0

class ASSET_OT_batch_generate_previews(Operator, ImportHelper):
    bl_idname = "asset.batch_generate_previews"
    bl_label = "Batch Generate Asset Previews"

    filter_glob: StringProperty(
        default="",
        options={"HIDDEN"},
        maxlen=255,  # Max internal buffer length, longer would be clamped.
    )

    recursive: bpy.props.BoolProperty(
        default=True,
        name="Recursive",
        description="Operate on blend files located in sub folders recursively\nIf unchecked it will only treat files in this folder",
    )

    def execute(self, context):
        folder = Path(self.filepath)
        if not folder.is_dir():
            folder = folder.parent
        if self.recursive:
            blends = [fp for fp in folder.glob("**/*.blend") if fp.is_file()]
        else:
            blends = [fp for fp in folder.glob("*.blend") if fp.is_file()]
        do_blends(blends)

        return {"FINISHED"}

def do_blends(blends, save=None):
    if save is not None:
        bpy.ops.wm.save_as_mainfile(filepath=str(save))

    if not blends:
        print("Batch conversion completed")
        return
    print(f"{len(blends)} files left")

    blend = blends.pop(0)
    bpy.ops.wm.open_mainfile(filepath=str(blend))

    bpy.app.timers.register(functools.partial(do_objs, blends, blend, [o for o in bpy.data.objects]))

def do_objs(blends, blend, objs):
    if objs:
        obj = objs.pop(0)
        obj.asset_mark()
        bpy.ops.ed.lib_id_generate_preview({"id": obj})
        return INTERVAL
    do_blends(blends, blend)
    return None

def menu_func_import(self, context):
    self.layout.operator(ASSET_OT_batch_generate_previews.bl_idname, text=ASSET_OT_batch_generate_previews.bl_label)

def register():
    bpy.utils.register_class(ASSET_OT_batch_generate_previews)
    bpy.types.TOPBAR_MT_file_import.append(menu_func_import)

def unregister():
    bpy.types.TOPBAR_MT_file_import.remove(menu_func_import)
    bpy.utils.unregister_class(ASSET_OT_batch_generate_previews)

if __name__ == "__main__":
    register()

If you want to know how it works, when you validate it scans the selected folder and all subfolders recursively, then iterates over them and marks all objects as assets and generates their previews.
I suggest opening the console beforehand with Window > Toggle System Console because the script will print out the current state and how many files have been treated in the console but Blender will be unresponsive for the time being.
You can find the script and a readme on my github page.

I don't think you need import os.

You could do it differently. make a Path from self.filepath and then use Path's parent method to get the dirname: p = Path(self.filepath).parent

This is great! Thank you so much for this!

@MartyFouts thanks, updated the script. It actually wasn't working for files with multiple objects so I changed it up a bit. Cheers


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Cycles render error
When I try to preview my animation on Concierge Render it gives me this error:
Error: Segmentation fault
I use cycles and picked GPU Compute on render settings.
I contacted the support line they sent me this: Array iterator out of range: Mesh_polygons_lookup_int (index 1099668583) and told me to check out my mesh polygons.
I'm very new to Blender and I couldn't find any information online to solve this issue. Any help is very much appreciated.
If there is any other information I should provide for better assistance please let me know.


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Copy attribute menu doesn't work on Blender 4.1.1
anyone experiences the copy attribute menu doesn't pop up at all even activating the addon? I've tried to disable other addons to see if something conflicted, no luck. It drives me crazy cause I use the menu very often. I'm using Blender 4.1.1 on Windows 11

Works fine here with Ctrl-C even popping up if you just have one object in the scene.

Can confirm, I took the init.py file from the addon and run it in the script editor a couple of times and it started working globally even after restarting blender


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Voxel Remesh for imported FBX
newbie question here. I imported a FBX model and want to remesh with the Voxel remesh. However it comes with a really strange result.
Any idea why? Thanks.

It can happen that faces imported from another format are not connected to each other. Go into edit mode, vertex select mode, right click , merge , by distance

Thanks! It makes perfect sense!


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Subdivision surface doesn't show vertex
I'm learning the sculpting course from CG boost and I had a weird issue. I saw in the tutorial Zach created a cube and merged it into a point, then he extruded the point to make a line. After that he added a subdivision surface modifier to add more points. The weird thing is, when I did the same thing, my spline didn't show the subdivided points like in the tutorial. Do you know why it's different? Thanks

Are you talking about right click > Subdivide? Make sure that you've selected the 2 vertices of your edge, and not only one vertex, it may be your problem here. If you're talking about a Subdivision Surface modifier, you need to apply it to create the additional vertices.

Thanks, I'm using the subdivision surface modifier. It works for sure after I apply the modifier. The thing is in the tutorial when you change the levels viewport, you can see the points increasing in the viewport. I can't see the realtime changing while tweaking the numbers. But yes subdivide might be a better way, thanks!

you need to apply the modifier to generate the new vertices. The number of Levels on the modifier will determine the number of 'cuts' or vertices in this case.

Switch back to Object mode and Apply the modifier and then you will see your new vertices if you return to Edit mode.

A slightly better way to do this is to create your line with two points. In Edit mode select both vertices then right click the line and choose Subdivide from the right click menu. A small menu will appear in the lower left of your viewport. Expand this and set the number of cuts you want.

@moonboots answered  in the comments while I was typing up my answer, but it is the same.

I've answered @moonboots thanks for you guys' input. I might just use subdivide


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Hair particles don't work properly
trying to do hair particles but it always starts at the 3D cursor and just goes a random direction

<-what it should look like
can anyone help?
emitter works fine

make a copy of the object and with that one apply all modifiers before you add hair, does it work? if it does check order of modifiers, maybe a subdiv is causing havoc

i have no modifiers active. i just shade smooth

is it possible you add the blend file so i can have look

https://drive.google.com/file/d/1Bmh67NW7LRbujjeLnM08DxHG5zF8ScZs/view?usp=sharing

You have it set to emitter not hair


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Blender UV bake looks different from nodes result
As the title said, I originally created the texture using nodes and when I UV unwrap it using bake it looks really different. Here's some image for details
Here's the node result:

The nodes:

And below is the bake result and settings:

Help really appreciated ! Thanks


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Voxel remesh in 2.9 has random broken ‘pores’ (pics), is there a fix?

I’ve searched on this topic and haven’t seen it addressed anywhere. I've also posted to blender devtalk on this but haven't heard from anyone yet.
When I voxel remesh a somewhat complex shape, I always get several (sometimes a lot) random weird holes (I’m calling them pores) in the result. I don’t think they are ‘poles’ because they occur even with pole correction on.
Below are a couple pictures of before remeshing and after, also showing a larger pore ‘blowout’.
I really need the voxel remesher (it is critical to my workflow) but I can’t fix this problem. I’ve tried everything from subdividing or decimating the original mesh and smoothing, relaxing, etc. with no luck. The ‘pores’ just move to different locations. If I increase the voxel density the pores just get smaller and often (but not always) different locations.
I’m really hoping somebody can help with this because I’m at a dead stop in my project until I can fix this.
Anybody else have this problem? Is it a known problem that I’ve missed in my searches?
Thanks any help is super-appreciated.
Original triangular (fully manifold, no intersections) mesh and description of ‘pores’ and ‘blowouts’:


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rigging separate objects to one skeleton
So recently ive decided to try to make a full model from sculpting,texturing and rigging it, though im a little stumped. i dont know much about rigging and was curious about how you rig separate object to the same rig. all the parts in green are separate and im not sure if theres a good way to use the same rig to for all of it withougt having to merge it all and keep the spikes from bending and looking floppy. also i cant seem to get rigify to to recognize the bottom jaw, i have control over the whole head but cant close the mouth and was wondering if theres a special thing you have to do for that

You can keep separate objects and parent them all to one unique armature, but in your case I'm not it has an interest. And you can always correct the weights in Weight Paint mode, so even if the Automatic Weight doesn't work fine with the jaw you'll be able to correct that.

ah i see i see, thank you


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How do i reduce density of retopo?
So im retopologizing a sculpt i did and part of the mesh gets very dense but im not really sure how to reduce this without ruining the flow of it. i tired a method shown in the bottom pic but kind of guessed and im not sure if thats the best way to go about it.

Tris can be a solution if it doesn't cause any problem when you bend the object, you need to test it, here is another solution to go from 3 faces to 1:

sorry for such a late reply but i havent been able to implement this until recently and it helps a lot thank you!


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is there anyway to bake displacement detail to a mesh so you dont have to use the map
So I recently sculpted a model in blender and was wondering if there's any way to bake the detail from the sculpt into a displacement map, pose the low poly model then add the detail back to the mesh using the map. I wanna try 3D printing it but it currently only uses a normal map which wouldn't show in a print. unless the only way is to rig and pose the high poly sculpt

Hello :). You can use the Displacement modifier, and simply apply it. That will turn displacement into real geometry. But why would you do that, when you already have the hi-res model?

the high res model lags my computer to move it and makes it impossible to do anything practical with it so I was looking for a way to be a little less hard on my pc


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Is there any way to apply a pose to a mesh and be able to remove the armature and keep the pose?
Im trying to import a model into the oculus home but when i do the character isnt posed but is in blender. idk if theres a way to fix this so oculus can read the armature pose or that i can fully apply all of the pose to the mesh

Yes: apply the mesh's armature modifier, then you can delete the armature. :)
Note: save backups as this is permanent

thank you! i didnt think the solution would be that easy


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Blender 3.4 OBJ 100X scale issue while export/import to/from other applications
I am trying to exporting models from blender to import in Marvelous Designer 12. Both application's unit setup is set at Centimeter. But still object appears 100X smaller in MD then Blender.
Tested in 3DSMax also and same issue in both applications. It seems like Blender unit is 100X smaller/larger then others.
Is this known issue? Has anyone have solution for this?
Please help. Thanks.

Hello and welcome. If this is indeed a bug, we won't be able to help and you will need to report the bug here https://wiki.blender.org/wiki/Process/Bug_Reports

@HarryMcKenzie I cannot confirm that this is a bug (I may also be mistaken). I have just tested this with Blender 3.4 and Marvelous Designer 12. Note: You also have the possibility to set the scaling when exporting in Blender, and also to influence the scaling in Marvelous Designer when importing.

The solution is simple (although it may be a bug in Blender):
Just use a different scaling (m instead of cm (DAZ Studio)) when importing into Marvelous Designer:

Or use other scaling settings when exporting from Blender:

By the way, the problem does not exist if you use FBX format instead of OBJ (more recommended in this case).

thanks for sharing! :)


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Painted color different to selected color
I'm just learning Blender and I've hit a wall with painting at the moment. The color which I select with the color picker isn't what shows up when used. Both with the fill tool as well as the brush. I've created a completely new scene and this still happens so can't be the scene. I've also tried deleting the brush and creating a new brush. Any help would be appreciated!
As you can see in the image I had an orange color selected but it painted yellow.

In what preview are you? What shading is used?

This is just the image painting window, there wouldn't be different shading modes would there? I'd assume it should be more like photoshop.
But if I view the object in viewport shading it has the same issue.

my bad. Sorry didn't notice you are in image editor

So it turns out since I had an aces colour space config on my PC which I used for Maya, Blender was picking this up and set it as my default colour space but the colour wheels don't change.
I just removed that and all is now as I would expect!


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How can I convert a mesh to a heightmap image using a scripting solution?
I have got about 20000 DEM tiles in form of .glb meshes.
What I want to do is converting those meshes to 16bit grayscale height maps (of course using a scripting solution since 20000 files are too many for manual work).
If you know another tool that can do this easier, please also let me know.
Thanks

I would use a Material node set up to make higher parts of the mesh lighter (with the geometry node, not geometry nodes), and then render with an orthographic camera. To make things quicker, you might try importing the mesh as shape keys or a point cache somehow, and animating between them, then rendering as an image sequence.

You probably want a tool like landserf that will read a dem and output a hgt file.  I suspect the tools that will do that automatically are expensive though.

Highly recommend GDAL.  Question may be more applicable on https://gis.stackexchange.com


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My projects are turning into my background
For some reason my project in material and render views are trying to copy my background, literally. I've tried installing reinstalling (My blender version was 2.83 now is 2.91) google, updating drivers, restarting my computer, starting a new project( it affects even my default cube), resetting my default settings, opening another project and I'm lost...
My computer has 15.9 gb for ram and it's a 2019 CyberPowerPC

https://blender.stackexchange.com/questions/linked/204297?sort=newest


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questions about viewport overlays

I didn't check center but it's showing me face's center
Is this supposed to be... or?

it looks like you see the face center if you enable Edges and choose face select mode, not sure why though

Hello :). Blender only shows face center when in Face select mode. Switch to edge/vertex select mode and it'll disappear. It has nothing to do with overlays.


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how project onto itself works?(snap)
I cant think of projections that how it works own my own I don't know why projection needed in snapping I want to know how projection works in snapping.

...Why 'Projection'? Because sometimes that's what it is.. (actually, internally, it always is). Here, the move is ShiftZ constrained to XY, so the snap is in X and Y only, projected down Z.

When Project onto Self is disabled, you can only snap to geometry of other objects.
It's useful when you go to Edit mode with multiple objects at once.
Notice I can only snap to the other object's vertices unless I enable Project onto Self.


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I dont fully understand about Recalculate normals
I dont really get this functions without explanations or images,
"These tools will recalculate the normals of selected faces so that they point outside (respectively inside) the volume that the face belongs to. The volume does not need to be closed; inside and outside are determined by the angles with adjacent faces."
what does the volume means? and I dont get respectively inside which mentioned above.
somebody please explain the upper italic section please.

The normal of a face is the blue line, starting from the center of the face and pointing as much orthogonal as possible away from a face: it can point in two directions: one side of the face or the other.
Two connected faces, if they stay onto two different planes, can be considered as part of a "sphere". Normals are calculated  outside or inside the volume of that ipothetical sphere.
In the case of more than two faces the calculation is repeated, guessing wich is the part to be considered "inside" and which one "outside", even when the "Volume" is not closed (as with the two faces example).


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Create texture image from mesh location
I'm stuck on an issue, that I hope some of you can help me with.
I'm trying to create 4 texture images, that hold XYZ values (+more) for a mesh. The problem is that I'm not 100% how it should be saved, nor how I'd go about it.
https://www.dropbox.com/s/838emnytm3dbow1/shader%2Bdds.zip?dl=0
Link to shader + dds texture.
It's basically a crawler track belt. It consists of joints, and it's the position and rotation of those joints I need to save. It's for the game Farming Simulator. I've included the shader that interprets the texture, and an original .dds file from the game. The array texture consists of 4 textures. The first one I know is the Y and Z locations, saved as blue and green. That can be seen in the bottom here:

This belt has 90 joints, so it's 90 pixels wide.
The second image I believe to be the rotation, saved as quaternions. Red and Alpha channel go between 0-1.
My second problem is what the 3rd and 4th picture actually do, and how they should be created. 3rd is very similar to the 1st, and 4th is very similar to the 2nd. I believe all the info is within the shader, but I have very limited knowledge and understading of such, to really know what it should do.
The whole idea is for the belt, that can be seen below, is just a flat mesh, but it is then curved by the trackArray texture using the shader. And in the game the mesh will scroll in the new shape, to create a nice belt for your tractor.

I saw this video on youtube, and he does sorta what I need to do through a script. So I'm fairly confident it can be done through a script in Blender. Can anyone take a look at the shader, and hopefully give me some pointers as to how it should be saved, and maybe how to go about the script?
It would be much appreciated.
Thank you.


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Cannot see keyframes for objects
I'm pretty new in Blender when it comes to the features, so I hope this is just a button I accidentally clicked.
I was animating as per usual, but then the keyframes for my non-greasepencil objects disappeared, they still move around as if the keyframes were still there. I can make new keyframes for the objects, but I can't see them either. I can see the keyframes for my greasepencil objects..

I don't know why, but deleting the old dope sheet and making a new one fixed it.


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Interact with Blender from external program
Is it possible to run blender from another python program? I need to start blender and execute multiple bpy commands. However, I cannot even figure a way to check whether the startup process of blender is already complete. Is there a way to do this? Also when Blender is open, amongst others I need to import a DXF file using the AutoCAD DXF add-on. But I do not want to call a dialog to select the file, instead I want to pass the filepath automatically to the code of the add-on and then let it do the import. But I can't figure out how. Anyone got experience with that? Also excuse me, if this is a super obvious question, I am a beginner with this.

Maybe this helps? https://blender.stackexchange.com/questions/1365/how-can-i-run-blender-from-command-line-or-a-python-script-without-opening-a-gui


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Is it possible to adjust pixels per inch of a image imported as plane.?
I am trying to simulate a display screen in blender. For that I imported the image that I want to display as a plane in blender. But the dimension of all the images imported as plane are fixed as 1mx1m even though the images have difference sizes. I want to simulate the display having a common pixel per inch that way I will obtain the images size according to their pixel dimension. Is there a way to simulate so?
Is it possible to fix the pixel per inch of image imported as plane in blender?

Sorry this first part because I am sure you know this, it is mostly for people who read this and might not know this: pixels per inch (ppi) is usually used for screen resolutions, how many pixels a monitor can show per inch. Many confuse this with dots per inch (dpi) and this is used for printing images, although in reality - especially in non-professional printing - images are mostly scaled to fit the size they are needed and not the size determined by the given dpi. Which means, if you have images of 1920×1080 pixels, they have these on-screen dimensions but can still be 72 dpi or 300 dpi. As I said, you might know it, just for other users reading this answer. This becomes important if you perhaps want to import images from different sources and they all have the same pixel dimensions, but if you scale them by their dpi you might end up with different sized image planes. This can be desired if the dpi setting is intentionally different, but can be irritating if you thought they should be the same size.
Anyway, have you tried the different options when you use the import Images as Planes? If you scroll down to the bottom there you will find Plane dimensions:

Absolute : there you can set the absolute Height of the image plane, 1 m is the default setting, Orientation > Align > Face Camera is optional and can be changed.

Camera Relative: lets you change between Fill (the image plane is scaled so that its shortest dimension fits the longest of the camera window) or Fit (the longest dimension of the image plane fits the shortest of the camera window). With this option, the Face Camera alignment is mandatory and cannot be changed. While on all other options the resulting plane size can easily be calculated from the image dimensions, here the plane size is dependent on the camera settings and the camera position relative to the 3D cursor (where the plane is placed).

Dpi and Dots/BU (dots per Blender unit): here you can define how many pixels of the image should equal (dpi) how many inches in real-life dimensions of the image plane or (dots/BU) how many Blender units of the image plane, with default Blender settings set to Metric this usually means pixels per meter. Alignment can be changed as well.

Thank you for the reply and proper explanation of the terms. Dpi options resolved my issue.

@Vidya Yeah, I guess in this case dpi is the best option to convert from ppi


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Is it possible to model a lens with fixed focal length?
I am trying to simulate a hexagonal shaped plano-convex lens with a fixed focal length of 3mm. Is there any way to simulate lens with fixed focal length in blender?
Length of the longest diameter of the lens is considered as 1.5mm and glass BDSF as the material to the lens with 1.5 IOR.

It might be. What is the context? Just a model? A render? How does it have to look, what does it have to do, what's the purpose? Even with recent significant improvements Cycles is not perfect for simulating refractive caustics (light going through lenses and hitting other objects), but it will show what one would see through a lens just fine.

I am trying simulated a lenslet array which will be used in a light field camera. It is not just a model. It needs all optical character of lens. So refractive caustics is not accurate in cycles?

Absolute terms like "accurate" do not apply to any rendering process or even computer simulations. You could say "accurate enough". Cycles is very slow with Caustics. LuxCoreRender, Octane or Maxwell or Thea render engines would probably be better for this. LuxCoreRender is probably best integrated to Blender and is open source and free so that's probably what you want to try.

In LuxCoreRender, Is it possible to simulate lens with fixed focal length?

An "accurate simulation" is an oxymoron, no? :) Do you want to do is set up a camera in Blender, that works like an orthographic camera on one axis, and like a perspective camera on another? Otherwise not sure what kind of an image would be produced by a lens like that - just a 2D image in a way? With one axis blurred?

It's not clear what the goal is. "simulated lenslet array which will be used in a light field camera" doesn't say much. How do you want to simulate it? Why? What's the context? What result are you after? What's it's purpose? Do you want to render an image as if it was taken by the camera or do you want to somehow visualise how that camera looks or works, or do you want to get insight how some geometry of the lens would actually work or something like that?..

I want to render the image as it was taken by the light field camera. The main difference of this camera from a normal camera is the placement of the lenslet array. The most basic element of a lenslet array is a hexagonal shaped plano-convex lens. So I'm trying to simulate a single hexagonally shaped plano-convex lens. The only constraint is that I need a lens with a fixed focal length.

That you can do. You need dense geometry so the curvature is represented well, but if you look through the lens, it will calculate refraction.  Cycles will ignore dispersion and some other effects, but that can work. See this: https://blender.stackexchange.com/a/126669/60759


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Rigging multiple 2d layered planes for feathers
So I'm trying to rig layered planes to use as layers of feathers and cant get the armature to fully influence the mesh and end up with horrible clipping issues. even when the bone says it has 100% weight it still leaves the mesh behind a little. I've tried with them all combined then each layer separately but had the same issue. I also tried subdividing but that didn't help either.


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Can you define a mesh as the boundary between two materials?
In the donut tutorial, the glass of water doesn't work because the water object and glass object both define their own surfaces, and those surfaces aren't exactly the same, leaving a gap between them.  This is solved by making the objects overlap slightly, so there is a thin sheet of "waterglass" in the middle.

Is this really the best solution?
Does the "waterglass" sheet have the properties of the glass, the water, or some mix of the two?  Wouldn't the last two cases make the refraction unrealistic?
This seems like a kludge to me, and I wonder if there's some way to define a mesh as the boundary between two volumes rather than needing one "outside surface" mesh for each boundary.

To create such a mesh, you could first make on that overlapped both, and then use 2 boolean modifiers set to difference to subtract out the volume of the two meshes.


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Two perpendicular faces are highlighted as one (upon selection)
Two perpendicular faces are highlighted as one upon selection. Actually the upper one is not recognized as a separate face at all (it lacks the dot in the middle). How has it happened and how can I fix it?

What you might be dealing with here is called an "ngon".  It's a shape that has more than four vertices.
It looks like you made a face of all of these verts with one F command before the top edge was made, or something similar.  So blender has done its best to draw it in a way that makes sense, but that is one face, technically.
It also looks like you have a couple of rogue edges down at the bottom.
In this case it's an easy fix, just select this top edge:

And hit J which is the shortcut for Connect Vertex Path.  It creates edges or splits faces where needed.

And what should I do with "rogue edges down at the bottom"? And how did they occur? Thank you!

just box select and delete them, when you're starting out you don't have a good grasp of the different modes, you might have been trying to do something related to object mode and didn't realize you duplicated an edge, or extruded a vertex or something.  They're pretty harmless since they don't have a face, so they won't affect your render, it's easy to not notice stuff like that


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Silicone material
How to create silicone material in Blender 3.X, such as on this image? (Shape doesn't matter - can be a cube).

Did you already try to use a little bit of SSS in the principle material node?

as Carlo says, try a bit of Subsurface, also mix with a bit of Translucent, lower down the Specular and the Roughness:

Thank you! I just saw here that silicone has IOR value of 4.24 ... Is this what is called "Subsurface IOR" in your image?

I also saw this which looks good, but it is an old version of Blender. And the instructions are not fully visible...

Yes maybe tweak the IOR to see if it has any effect


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How to define dependent geometries (e.g. for a male-female connector design)
Is there a way to define dependent geometries? For instance while designing a male-female components of a connector I want that if I change something in the male component - the female component will adopt itself automatically to the change (and vice versa).

you can use the slice in the bool tool , remember you should use brush for not automatically applying the modifier , should i elaborate?

Yes, please. With an example, if possible. Thank you!

wait for few minutes :)

The plan is to use the Bool tool addon that is Default in blender and can be activated in Edit > Preferences > Addons ,then create a big cube

this will act as a female port holder , where we will create our female port
Now you can add another small cube to be used as our male adapter

Then select the small cube > then the big cube(please follow the order) and click  N
to open properties tab , go to Edit tab and expand Bool Tool to find the brushes.

now Choose the slice option .You can notice that the part of smaller cube intersecting with the mesh has sliced it to create a new block , now you can change the geometry of the original small cube to change the slicing in both big and sliced cube

This method is responsive and geometry changes in real time
for legos this can be done with a boolean brush
Model a Lego

Make sure that the bottom of the lego is a little bigger and the top a little smaller then duplicate the lego and put it a little above the first lego.

Run a boolean brush , like this (Remember select the bottom lego first )-

Thank you! Will this work also if male/female components are parts of the same object? Like a Lego brick?

the example i have shown you easily works for usb , yess you can try this for lego also

i have edited the awnsere and added for legos also


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Generate 2D engineering drafts based on 3D model
Is there a way to automatically generate such detailed 2D engineering drafts from a 3D model:

https://blender.stackexchange.com/questions/90192/making-diagrams-and-blueprints-for-engineering

https://blender.stackexchange.com/questions/766/can-i-export-a-pdf-from-blender


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Strange triangle artifacts on bevelling but no rounding
I get strange triangle artifacts on bevelling but no rounding of edges. Why and how can I overcome this?

Try to select all vertexes and press M -> by distance.

Is this "Merge by distance"? If yes - I did this. 0 vertices were merged. And I still have the same artifacts...

in this case, can you share the file?