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How do I edge split after I duplicated a face?
I was creating a hand from a tutorial but when it came to the part where you needed to duplicate the face of the hand and edge split it by pressing space, it didn't work. keeps saying "error cannot split selected faces" Am I clicking the wrong key? or did I messed up my key binds?     YouTube tutorial TIME(5:04)(https://www.youtube.com/watch?v=z-SNS_98FkM)

Can you add your blend file to your question?  You're not clicking the wrong key.  The message mentions 'split' so it's trying to do what you want.  If you get that message when you try split with that screen shot, it's failing because it wants to split all four of the selected faces from something, but there's nothing to split them from.

or just make a small video with the last 3 steps you do before your error happens. but with full window please.

Try with ALT + M > Faces by Edges

tysm for helping me, the alt + m worked and i have completed making my hand


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Accesing individual values in PropertyGroup via .prop in the menu
I need some help with properties. I have a property class, pretty straight forward stuff
class My_Settings(bpy.types.PropertyGroup):
    prop_1: bpy.props.IntProperty(name="Some prop", default=0)
    prop_2: bpy.props.IntProperty(name="Another prop", default=0)

I register the class and assign it to scene as
bpy.types.Scene.my_props = bpy.props.CollectionProperty(type=My_Settings)

I use another class to add instances of those properties:
class My_add_property(bpy.types.Operator):
    bl_idname = "add_fields"
    bl_label = "Add input fields"

    def execute(self, context):
        inst_prop = bpy.context.scene.my_props.add()
        inst_prop.prop_1 = 0
        inst_prop.prop_2 = 1
        return {'FINISHED'}

I draw a menu, use My_add_prop as a button to add instances
class My_menu(bpy.types.Panel):
    bl_idname = "my_menu"
    bl_label = "Menu"

    def draw(self, context):
        self.layout = lay
        lay.operator('add_fields', text="Add prop")

        '''But I have no idea how to access individual properties do draw them into menu.
         I assume it's going to be something like that, but how can I actually get to
         individual values?'''

        for i in bpy.context.scene.my_props:
            lay.prop(context.scene, "my_props")
            lay.prop(context.scene, "my_props")

Also, ts there a method to remove last property set? I'd like to make class/button that removes the last set.
Thanks for help!

Well, I finally figured it out. the last block in the menu should look like that
 for i in bpy.context.scene.my_props:
        lay.prop(i, "prop_1")
        lay.prop(i, "prop_2")

Now i feel kind of stupid...
Also if you want to go on removing last set of properties, you can go with
bpy.context.scene.inset_props.remove(1)

This appears to be removing sets of properties one by one until it hits the (1) one.
Hope it helps someone in the future!

source: Stack Exchange

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

sort: votes


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How to make texture white in the locations that objects hit it?
I have a cylinder with various glass objects sticking out of the sides:

This cylinder has a texture:

I would like the texture to have white spots in all the places that are intersected by glass objects. How do I do that?
It would be very nice if it could be done with just nodes, but, if not, thats also fine.

Could you include a picture with the result you would like to obtain?

@FacebFaceb  I'm not quite sure how I would go about doing that... without the glass things, it would look kinda like a mushroom from all the white circles in it.

An option could be the 'dynamic paint' in the physics tab, where the textured mesh is a canvas and each sphere is a brush

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


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What are the differences between preview render hair and rendered hair?
Preview render is showing the hair like so:

But, the rendered hair just completely destroys the beauty lower formation and instead smooths it out so it looks ugly like this

I've noticed numerous quirks with this as well. It would be great to get a definitive answer on how to match preview and render settings for hair.

@Sazerac I think I figured it out.

The only differences as far as I can tell is the confusing steps variable in the render subcategory and the steps variable in the display category.
Once I make both of them two, the renders turn out exactly the same.

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


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How can I create a silhouette using HDR in cycles?
In real life, when taking pictures with a bright background the object you are looking at becomes mostly black. How can I get this effect in Blender?

I would like the monkey to become a silhouette without using any compositor or material hacks.

I'm not sure if my HDR image has a high-enough dynamic range to actually do this, so feel free to user your own HDR instead of mine.
The HDR was too big to pack into the Blend file. Here it is:
https://drive.google.com/file/d/0Bxf7lERLL3TlQkM2a2FKSkRRMk0/view?usp=sharing

Ah, sorry. I had turned on auto-packing and assumed that it would automatically pack itself.

In addition to the dynamic range of the light coming from the surrounding environment, also consider the dynamic range and exposure level of the camera.
If your HDRi is significantly brighter on one side, then it should be as simple as pointing the camera into the sunset (or whatever the source of bright light is) and adjusting the exposure so that the background is properly exposed (not too blown out).
With my own HDR (yours doesn't seem to have been packed into the .blend):

Also note that I've increased the focal length of the camera, to match the aesthetic of your reference image more closely.
While on the subject of handling the "camera side" of rendering, I'd highly recommend taking a look at Render with a wider dynamic range in cycles to produce photorealistic looking images.

Another great answer :)


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How to model a tinfoil hat? (aluminium foil texture as a mesh)

I want to model a tinfoil hat. What techniques should I use for modeling with tinfoil? I actually want the hat to be made of mesh (I don't want a texturing solution).

You may achieve it randomizing the mesh a bit using simple modeling tools, but it demands some experimenting to make it look good.

Model the hat starting from a cube subdivided with a subsurf modifier (4-5 subdivisions). Apply the modifier. Subdivide the hat (with W-->Subdivide) to create a dense geometry. With the all vertices selected press Ctrl+T to trangulate faces. Unselect everything with A, go to Select-->Random (set it's value to about 30-50%), then press Ctrl+E-->Rotate Edge CW. It'll give a bit randomness to the mesh's vertices positions.

Grab selected vertices upwards (G,Z), then scale them outwards a bit (S). Crease the selected vertices with Shift+E. Add a subsurf modifier and smooth the mesh (T-->Edit-->Shading-->Smooth).

Finally to randomize the look of the hat even more, select some vertices and press Ctrl+V-->Smooth Vertex.

That's what they WANT you to think...

Another great modeling answer! I am always surprised by the way you can take a complex modeling job and break it down in to something so simple. In my mind modeling all those random creases, was too something too complex. Very well done.

Nice, quick to the point and includes gifs, images, and Screencast keys, good job.

Here is a solution with more realistic render results (but be careful with the number of polygons, keep in mind how performant your computer is). Also with a mesh by applying the displacement.

Add a Subsurf (of 4 or more if possible), Displace (Midlevel:0, Strength:0.04 depending on the texture), Solidify (Keep that order in the modifier stack from top to bottom)
The displace should have an aluminium texture
Unwrap your hat - In edit mode A (select all) then U (Unwrap) then Minimize Stretch option
Apply the Subsurf then the Displace modifier
No need to apply the Solidify modifier
Decide if you Smooth the shading or keep it Flat
Done

TIP: try to have a texture that does not have too many dark (reflection) areas, as this would result in a weird displacement. Mine comes from here https://www.shutterstock.com/pic-48906235.html

The only problem with this method is that if you zoom in, you can see the pixels

It depends on the size of your texture, on your level of subdivision, and in order to break the regularity you can use Triangulate modifier. If you use Smooth shading there are normally no "pixels" anyway.


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How to convert to Mesh from Curve with Python
I'm making a bunch of abstract objects that are shaped programmatically. I use a Bezier curve, you get nice molds with few points. Then I need to convert it into a mesh object. Blender version is 2.80.
It's easy to get a mesh object from a curve manually:

Keep the original curve object so it can be reused:

In edit mode the vertices are there so it really is a mesh object:

Now how you do the same with a Python script? I've tried this that and the other but only got various error messages. I'm sure there must be a simple way to do that. Let's not go through all my trials but I attach some error messages just to show you I've been working on this:

RuntimeError: Operator bpy.ops.object.convert.poll() failed, context is incorrect
RuntimeError: Error: Can not create object in main database with an evaluated data data-block
ReferenceError: StructRNA of type Mesh has been removed

Turned out that I don't need to do that because I found Screw Modifier that does everything (that I didn't even describe here), and this step became a misstep. The problem has vanished.

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


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Change default size for exporting uv maps as an image?
Is there a way to set the default exported uv map size to 2048 instead of 1024 so it would show up as 2048 instead?

I am also looking for the same.


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How To Carve a Design
I'm trying to model this sword, and I'm having trouble making the base of the sword (the grip). How would I go about doing this?

What will you use it for? Rendering, 3d printing, game asset?

I don't really think this is a case for sculpting, as this is hard surface modeling when you want to model forms of the mesh, smoothen them with Subsurf and refine the mesh to keep sharp edges where needed. There are quite a few of techniques for that all falling under term "hard surface modeling". This question is a bit too broad though for this site as of now

I'd suggest modelling the basic shape and then sculpting, then you can retopo a low poly and bake the detail from the sculpted piece to the low poly, if you are planning on it being a game ready asset.
If you aren't, just stopping after the sculpting phase is OK.

is there a video you could link me cause i barely know sculpting

take a look at these,
https://www.youtube.com/watch?v=uVpwivEl_6o
https://www.youtube.com/watch?v=tZnUgt659oI Sculpting is very different from traditional modelling, so it might take some time to get used to it.

You can also paint a bump map manually if you are already going to be using image textures in your material.

sculpting and retopo is the best approach


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Removing automaticly generated (automatic weights) weight paint
I'm very new to the topic of weight painting, and have just parented several meshes to a rig.
It all works well, except for one issue at the shoes (the bone of one leg not only drags that leg, but also the other one).
I selected the bone, and then the object that I was having trouble with (opposite shoe), and, sure enough, there was some weight painting on the shoe. I changed the brush to subtract, and dragged all of the levels (weight, radius and strength) up to their maximum. I then tried to remove the weight paint, but it was not subtracted.
Strangely, adding my own weight paint and then trying to remove it works; it is only the auto-generated weight paint that will not go away.
Here's my file:
http://www.mediafire.com/?s30kckfkhqx8ga4

What causes the problem is the Mirror modifier in the shoes. The Vertex Groups option of Mirror modifier is on by default, and it's unchanged here. That option mirrors weight in vertex groups with symmetrical names. That is, for every pair of vertex groups suffixed with .L and .R, Blender will just match vertex weights in both, even if you only assign weights to one of them.
The problem is, Blender assumes the object's symmetry coincides with armature name symmetry, while your objects are not. Instead of mirroring the left shoe for the right shoe, thereby matches the armature's shoe.L and shoe.R and works as expected, you're mirroring each half of each shoe.
The solution is easy: For each foot, either delete the (unused) vertex group for the other foot, uncheck Vertex Groups in the Mirror modifier's setting, or apply the Mirror modifier.

Well, the first thing you might want to do is to give your bones descriptive names. Then it's much easier to know which vertex groups are relevant for a given mesh. Since the bone names and vertex groups in your case are connected, you just need to rename one or the other and both will have the new name.

The safest way to keep the left foot bone from affecting the right foot mesh is to remove the entire vertex group from that mesh. It'll never need it anyway. This is possible since your character's feet are separate objects.
In case you use just one mesh and removing the vertex group is not an option, instead of setting the weight to 0, remove the verts of the left shoe from the shoe.R group.
So I would suggest:
Name your Bones, so the connection between vertex groups and bones becomes more transparent. Keep them symmetrical with .R and .L suffixes. One way to do it is in the outliner by selecting a bone and Ctrl-LMB on the name. Or use the text button in the Bones section of the armature data.
Then select your right shoe object, select the shoe.L or foot.L vertex group and click the little - sign to throw out all the unnecessary vertex groups.


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Image not spreading on the whole face
I am learning UV mapping, trying to map an image on one side of a cube but it does not spread properly on the whole face.. Here is what I get:

I know this can be done simply by applying materials to the specified sides but I want to apply different images in future. Can anyone tell me what is going on? I want to color the central part only, not the boundary.
Thanks

I have a feeling that you have a bevel modifier which is messing this up. If you do have a bevel modifier, make sure the limit method is set to Angle.

bevel and subsurface division. I wanted to give this curved look around the edges.

Make sure the limit method on the bevel modifier is set to angle, so that only the edges between faces with very different normals are beveled:

If you have the limit method set to none, the edges on the flat parts of the cube will be beveled (which creates extra geometry without changing the shape), and the UVs are not interpolated correctly:


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Black lines while painting
I've seen similar questions being answered, but none of the solutions helped me.
Basically, there are black lines along the edges on my texture.

What I already tried:

Increase bleed on brush - I increased it to a max of 8px, but it removed only a part of these lines
Recalculate normals - didn't help
Remove doubles - there was no doubles, so it didn't help
Manual unwrapping - didn't help either

Btw I use Cycles render if it's important.
What else can I do? The only way I can get rid of these lines in to paint right on the uv map but it's really uncomfortable.
Help, please...
Also, with bleed maxed out, uv map looks odd:

Is you object scaled very high or very small? If so, it could be due to rounding imprecision. Try selecting the object and choosing Apply Scale and see if that helps.

If painting directly on the map, outside of the borders of your UV, fixes it, then it is a filtering/mipmapping issue that can be solved by increasing the bleed.
Don't worry about what your texture looks like out of the borders-- don't worry that it looks weird.  It's supposed to look like that.  That's not an odd image, an odd image is an image without any painted margins.
How much bleed should you use?  About half of the smallest distance between UV islands.  Ideally, your UV map is so well arranged that all verts of all islands are equally spaced and your entire image gets painted with bleed.
Increasing the bleed alone is not enough; it only paints bleed when you actually paint.  So in addition to increasing bleed, you need to actually paint over those edges again.  From the looks of your image, you painted, then increased bleed, then painted some more, but did not necessarily overpaint areas you already painted.  Which could easily explain your edges appearing only in some places....


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Objects Not Showing in Other Workspace Viewports, Only Default
I'm having this issue where my objects only show up in default view. When I switch to the other workspaces; UV editing, compositing, Nothing shows up at all; not even the cameras, lighting, either. The names show up in the outliner, but in the viewport of the other workspaces. Nothing.

Tried changing Clipping Distance: Didn't work
Tried to switch the interface windows around: Didn't Work
I am Using Blender 2.79b
I am in Cycles Mode, I don't care about Blender Internal Render
I tried changing some of the windows to 3D view in the other workspaces: Didn't work
I am using the Pie Menu add-on, idk if that could be a problem

You are in Local View, check your viewport label on the top left.
Local view is stored per viewport, so switching layouts or windows doesn't carry it over, though switching scenes in the viewport does.
Exit Local View mode to view your scene, either using Numpad / or in the 3D view header choose the menu option View > View Global/Local to toggle.

another problem, I'm using a keyboard w/o a numpad. is there an alternative hotkey?

Omg thank you so much. I was scared that I might lose my model. Much much thanks!

Check above, answer updated

I know there should be a solution inside blender properties, but none of the above worked for me, so I deleted and added back the background images, and it is viewable now.


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Sphere photos for Facebook
I'm trying to make a 360-degree panoramic photo for Facebook. Example shown below

However, when I upload a photo made with blender it does not seem to detect that it is a photo made to do this. I set my camera up so it would render images based off the docs and this question.
How can I achieve what I want to do?
If it makes a difference I have Blender 2.78a and I am using the Cycles Render

Most likely you need to include the relevant exif tag to indicate the correct image type for facebook to interpret as a 360 image. See https://www.facebook.com/notes/eric-cheng/editing-360-photos-injecting-metadata/10156930564975277/. In particular, you could try using exiftool to add the projection type with "exiftool -ProjectionType="equirectangular" photo.jpg".

@RichSedman That sounds right thank you. I'll look into it

Hi @Dan. You'll need to ensure to use JPG file format for this - Facebook seems to ignore the ProjectionType for PNGs. I've added an answer including the 'exiftool' command line to use.

For Facebook to interpret an image as a 360-degree panorama, it needs to have the following properties :

It must be in 2:1 aspect ratio. eg, 4000x2000 pixels
It should be in JPG format (it seems that the panorama settings are ignored for PNGs!)
It needs the EXIF tag 'ProjectionType' set to 'equirectangular'.

For more information see this Facebook link about Editing 360 Photos & Injecting Metadata.
To achieve this, once you have rendered your image (using an Equirectangular camera - which should be oriented level with the horizon rather than tilted) and saved it in JPG format, use a tool such as 'exiftool' (or another tool that allows you to manually specify EXIF tags) to set ProjectionType - eg, with the following command line :
    exiftool -ProjectionType="equirectangular" <filename>.jpg

This will add the relevant EXIF tag to the image (saving the original as an '_old' file). The resultant file should now be successfully interpreted by Facebook as a panoramic image.

EDIT : Here's an additional source of useful information - http://atterer.org/tech/android-exif-tags-xmp-pano-panorama-exiftool, including additional tags that should allow you to tweak the panoramic view as desired (NOTE : I don't know which of these are actually honored by Facebook, but worth a try) - replace the settings with your own image dimensions, etc. :
    exiftool -UsePanoramaViewer=True -ProjectionType=equirectangular  PoseHeadingDegrees=180.0 -CroppedAreaLeftPixels=0 -FullPanoWidthPixels=8000 -CroppedAreaImageHeightPixels=4000 -FullPanoHeightPixels=4000 -CroppedAreaImageWidthPixels=8000 -CroppedAreaTopPixels=0 -LargestValidInteriorRectLeft=0 -LargestValidInteriorRectTop=0 -LargestValidInteriorRectWidth=8000 -LargestValidInteriorRectHeight=4000 filename.jpeg

Thank you. I will try this in a few hours when I get home

Where you have the numbers 4000 and 8000 should I change them to 3000 and 6000 as the page you linked said 6000 x 3000 was the max resolution

I've only actually tried it up to 4000x2000 and that sample command-line needs the relevant image dimensions in place of the 4000 and 8000, but, yes, you're right - the page does mention those maximum sizes. I got it working with just ProjectionType=equirectangular and didn't need to specify the rest. I mentioned those others just in case they are helpful for tweaking the result (such as specifying the initial direction or different cropping) but I don't know if Facebook even takes note of those others if you specify them (but they might be useful!). Best to leave them out if unsure.

Ah okay. Thank you for your help with this :)


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2.81: Align objects by specified point
I have several arbitrary objects. I need to align them along a line by specified points. I have tried to do it with Origin point, but no success.
Any suggestions?

EDIT 1
"Oscurart Tools" solves the problem but partly. It distributes objects along the straight line only. See the image below :|

One way would be to use the Oscurart Tools addon.
It can align origin points between multiple objects.

Enable the addon ✓ in Preferences > Add-ons

Select your objects (order matters) and RMB > Oscurart Tools > Distribute

Each cone has origin point in it's tip. After aligning, all the origin points are in line.
(The blue line is just for illustration)

@JACHYM Thank you. But there are 2 points about Oscurart Tools: 1 - using this tool I need to align the first and the last object nevertheless, 2 - it doesn't work for curves (see my Edit 1 in the question).

Hello again :). Aligning along curve is a completely different thing. But these threads could help https://blender.stackexchange.com/q/161169/78972, https://blender.stackexchange.com/a/65571/78972


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How can I fix this uv unwrapping issue?
So I tried making this human model from a tutorial, but when I try to texture it, the uv mapping is acting all weird. The chest area is really disproportionate from the rest of the body:

When I tell blender to unwrap everything, it makes the upper body tiles really small for some reason:

I probably just need to add some seams here an there, but I can't quite put my finger around it. How do I fix this?
Here's the blend:
http://pasteall.org/blend/index.php?id=50207

There are not enough seam cuts, you really have to think like you're cutting the shirt with scissors, otherwise Blender can't properly unfold the mesh. If you add some additional seams on the shoulder and on the sides it will map properly.

Short, precise, well illustrated - good answer!


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emission shader casting shadows - problem not solved
There is already a post about it in here, but the problem is not solved, in fact it is not a solution to the problem. What can we do to avoid shadows from emission shaders?
There's a similar post about it in here, and still the problem is not solved, and it seems: LIGHT PATHS CANNOT BE USED FOR MESH LIGHTS.
Here is a blend file that contains a simple experiment that demonstrates that the aforementioned solution in the first link does not work:

So, how do we avoid mesh lights to cast shadows?

Is this what you want?
https://snapr.pw/i/4ce8554edd.png

@Ezra, yes, how did you obtain it?

I used the diffuse factor of a light path node to mix the diffuse shader of the cube with a transparent  shader. Using the reflection output of the light path node gives the same result, so you might need to use both for more complex scenes.

@Ezra, do you mean the 'Is Shadow Ray' factor of light path - it won't work with 'Is Diffuse Ray'. Also, this would have to be applied to all materials and would have the effect of removing shadows from all light sources rather than individually. One of the linked wuestions indicates disabling the shadows from all but one of the sources.

Try this:
https://snapr.pw/i/1446ab92dd.png

@Ezra, it doesn't really work

@BumbleBee it's weird, because it works when I try it. If you want a solid solution, I would go for using multiple layers.

@Ezra, yes, I've found using multiple render layers is the only solution and then we must composite them together.

Cycles doesn't have a light group solution, do you happen to know an addon as such?

In your particular example case you could replace your emitter object with an area lamp - this does support suppressing shadows as shown :
3d View :

Cast Shadow disabled :

Cast Shadow enabled :

However, I don't think it's possible to suppress shadows from mesh-based emission materials due to the nature of the physics based rendering. ie, if you're suppressing light from emission surfaces then what about light reflected from a glossy surface - that could also cast shadows - as could light from a diffuse surface (albeit much more subtle, but it would still be a shadow).

I deliberately was forming a simple scene here. To point out that the shadows do form

Though, what you said is true

I did think it was deliberately simplified. Do you have a specific practical situation in mind where the area lamp wouldn't be a suitable substitute?

I think emitters are particularly good for fill lights, but they cast shadows. Spots are better for casting sharp shadows. Emitters behave more like those metal sheets that emit in uni direction.

The area lamp appears to produce pretty much identical results when compared to a rectangular mesh emitter - with the exception that the intensity for an area lamp is for the whole lamp whereas for an emitter it's per unit area (so double the size of emitter would produce an output 4 times stronger). The only reason I can see for using a mesh emitter is where the geometry of the emitter is significant - eg, modelling the filament of a light bulb - in which case you'd be looking for realism, including casting shadows. For general illumination, the area lamp is surely the better option.


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What methods are there to level your particle hair?
How can we very sharply level particle hair? The default settings are very good for random particle hair but for actually doing the opposite thing, what are the methods?

For example like the blanket above, as you can see some of the hair is pushed inside and some are way too long. How can we level them so that their hair(or fur), become more like that of a toothbrush? Sharply leveled. The idea is to create a plane leveled hair and then added with brownian and some clumps and curls settings to create a realistic blanket(using a texture as a source of color).  Here is the blend file in case the example can be clearly shown with the file itself:

Mainly, you have a non default parameter here : the brownian (agitation) field set to a value. Set it back to 0 to have a regular aspect.
After that, as you want to have a short hair (like brush), you may lower the segments (as their are used for the hair movement, mainly for long hair).
And to have more density, simply grow the amount of emitted particles.

As some faces are not visible, you should also use a vertex group to locate the hair where you want on the visible faces : in consequence, the visible faces will have more hair on them with the same or lower overall hair amount.

I have another question though. After we shape the hair using the particle settings we cannot further fine tune it in particle edit mode. Is there a way to apply the settings so that we could fine tune it in particle edit mode?

did you remodel the mesh? I copied the settings exactly in the screenshot. Since, I'd like then  hair to be visible in all faces I assigned all a vertex group:

though the hair length of 2 was very long for me(I don't know how), and I had to set it to 0.2.

@BumbleBee, maybe I have applied scale or something (I dont remember)

really? No matter what I tweak it doesn't seem to work and do you know also about the question I have asked in the question above?

@BumbleBee, this last file contains several parameters which are different from your initial file : a/ in the render section "end time" set to 1 instead of 0.0something (if you want to keep 1, lower the hair length as 0.0something lower the lenght as they cannot grow). b/ in the children section mode set to 'none' instead of 'interpolated'. Understand that if you change all these numerous parameters it's not possible for someone else to give a full check each time, thanks...

sorry for the trouble. I'm very bad with particles

The problem was, the modifier was not applied

do you also know about the question mentioned in the comment above?


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Why can't the 32 bit version of blender 2.78 use alpha channels?
The node setup is quite simple:

and the experimental image is :

(only the red is opaque other part is transparent).
So why can't we texture images with alpha values? Is this a bug?   I've tried JPEGs and it works fine but we can't texture objects with any image textures that have alpha.
Note, this is the problem with the 32-bit version of blender 2.78, I don't know about the 64-bit version since it didn't work on my PC.
Please see the comments below before downloading the blend. The problem would not be evident unless the file is unpacked.

The magenta color on the sphere suggests that there is a problem with the loading of your texture. Can you see the image correctly in blender's image viewer?

@Gez, let me upload the blend

@Gez, I  was on my way to packing the files when the texture worked.Is it having problem following the directory then? It only works when the file is packed within blender? Should I upload the file anyway?

@cegaton, I know that's why it maps jpeg. and I uploaded the blend file, did you check it out? unpacked the folder and tried the texture on?


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How to join joints ( Armature )?
I'm new at Blender and I'm trying to make a chibi human character. As the pictures show, I'm trying to join 2 joints. Do you know how to do this?

I think your illustration could be a little clearer.. to indicate exactly what you mean by 'join joints' to people not familiar with your rig?

The image is unclear. I cannot tell what end of either bone I am looking at.
To make a child bone connect to its parent after parenting, select the child bone, then go to Properties editor -> Bone properties -> Relations panel -> Connected, and check it.
To parent one bone to another in a connected manner, select the desired child bone, then the desired parent bone (so the parent will be active), and strike Ctrl + P. In the appearing Parent menu, click “Connected.”
PS: a child bone’s tail can never truly connect to its parent’s tail.


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How can I create Meteoric Metal in blender?
so I saw this post on reddit recently but the post is 7 years old so I don't know if the OP will respond but basically I want to create meteoric metal in blender for some projects
here is the link to the reddit post for clarity on what i want to make exactly:

any advice will be appreciated https://www.reddit.com/r/blender/comments/6wxuou/meteorite_iron_material/

Hello and welcome. This sounds like a request for free work, there are many ways to combine nodes for procedural textures, combining the use of multiple Voronoi textures.

Please clarify your specific problem or provide additional details to highlight exactly what you need. As it's currently written, it's hard to tell exactly what you're asking.

The question seems OK to me. It is asking how to make something. Seems like a good question for BSE. @KISKAart, I really don't see how this may seem like request for free work - they are not asking for providing the result. I think people not familiar with what is possible with nodes may sometimes just not know where to start.

@MartynasŽiemys Sorry, my mistake, at first I thought the question was: "How do you get this result from reddit?"

Please be advised as Martynas said in their answer that you should never use a render as a reference for a real object, you should always strive to get a reference of the real thing, ideally several references from diferent angles, lighting setups. Otherwise you risk amplifying biases and defaults that should not exist. Cheers

Looks like some sort of scratches directional in 3 directions. I don't think it has anything to do with Meteoric metal though as that looks very different. Have a look at the real thing maybe instead of looking at someone's interpretation, but if you want to have a copy of this copy...
You could stretch some noise scaling it's coordinates and also rotate it 60° while repeating 3 times. Use Map Range or Math in Grater/Less Than modes to make the scratches sharp:

You could also mix more various noises on top or maybe to make more complex directional patterns that would then be repeated rotated.
The idea would probably be to create some more interesting metallic shader as well. This could possibly match your reference. However, you could consider getting a more realistic reference, because real meteoric iron patterns may look very differently:

Source: https://www.fossilera.com/meteorites/2-24-etched-iron-meteorite-slice-155-5-g-section-nwa-11289


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sculpt mode symmetry mirror mode not working
sculpt mode symmetry mirror mode not working,
i dont know what is going on so i summon help from designers here

The symmetry is calculated around the object's origin, so check if your model has its origin in a correct location (and sculpt in loc 000, rot 000 and scale 111, as a good habit).
If not, select a vertex on the center line of the model, press Shift+S > Cursor to Selected, then in Object Mode, right click and set Origin > Origin to 3D Cursor.
Now in Sculpt Mode you can use the "Symmetrize" operator, choosing if to copy from -X to + X or vice versa.

https://prnt.sc/Ml_rYXLVcMDH help, did the  * If not, select a vertex on the center line of the model, press Shift+S > Cursor to Selected, then in Object Mode, right click and set Origin > Origin to 3D Cursor. * but that is the result https://workupload.com/file/6SyVGWhVqU6 if you use simmetrize will do a horrible monster

That's because the rotation of your model is not 0,0,0. To solve select the model in obj mode, press Ctrl A > Apply Rotation, then in Edit mode Symmetrize from + X to - X. As I said in my answer, you should sculpt in Loc 000, Rot 000 and Scale 111 (use Apply operator if necessary).


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Is it possible to create a fog / smoke aura in Blender?
I don't know how to name this effect, but I want to recreate this sort of fog that circles the character. Thank you!

is this character 2d or 3d? 3d: you could try this and render or apply at the appropriate frame?  I can't think of a shaders approach.

Is a 3D character. Thank you! I'm going to take a look


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Can Blender be made to indicate directly, if auto-saving is in progress?
If Blender is unresponsive, I can only tell if that's due to auto-saving, by looking at the disk footprint in Task Manager.
This problem is giving me a headache. Is there any way to achieve an indication of auto-save status from within the application?

Hi, this is question and answer site about using Blender. For general discussion try blenderartists forums, for feature suggestions there is Right-Click Select. Opinion based questions and feature requests will get closed here. If you want a solution for a problem, maybe edit the question and form it as a question.

For the reasons given by @MartynasŽiemys, I've tried to rephrase this question to fit with BSE's remit. I hope the edit catches your meaning. The part of your post that's a feature-request to the developers, should be posted on Right-Click-Select. (Good Idea, BTW. :)  )

@Robin Betts Thanks for the review, exactly what I wanted to express, I will go to Right-Click Select to submit my thoughts, thanks again


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Possible to join as shapes with differing number of vertices
So I'm trying to join 2 different shapes together but Blender outputs an error saying it can't due to differing number of vertices. I've tried figuring out if there is anyway around this but haven't found any quick solutions for my use case other than either adding a lattice and manipulating the base shape to cover/fit the model shape, or pull single vertices to do the same which honestly doesn't look that great afterwards.
So my main question is, is there a way to get the base shape to follow my model shape to ease this process?
.. Or am I out of luck with that, and if so is there possibly an easier way than what I explained that I am doing earlier?

Please add some images to your question so that we can see what you're talking about! https://meta.stackexchange.com/questions/75491/how-to-upload-an-image-to-a-post

Agree with John. The reason this isn't a button you can push, is that it will depend on topology,  case-by-case. Shape-keys are a simple linear interpolation between vertices with the same index.


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Transform object to put two faces into same plane (Blender 2.8)
I have two objects. I would like to transform the left object so that face A of the left object is in the same plane as face B of the right object. In the object properties panel, each of the objects has 0° of rotation on each axis.

For this example, I have used cubes for simplicity. However, in real life I often have two different objects that I would like to align on a specific face just like this.

If you don't mind, or want to, align the left object's local axes to one of its faces,then you can use a method like this one
However, if you want to retain the left object's local axis orientation with respect to its mesh, you can hand over the job of alignment to an intermediate parent object.

In Edit Mode, select the face you want to align. ShiftS Cursor to selected, ShiftNumpad 7 align the view to the face.
Back in Object Mode, ShiftA with 'Align to View' checked, create a helper cube, centered and correctly oriented:

If you like, at this stage, you could rotate the helper 180 around its Y or X, in Object Mode, so its Z is pointing into the face to be aligned.

CtrlP and 'Keep Transform', make the new helper parent to the left object.
In Edit Mode, select the target face on the right object, and create a Custom Orientation from it. (2.79, Ctrl Alt Space, 2.8, Header, Transform Orientation dropdown, '+').
Make sure it's in use for the next step.

With the helper selected, Header > Object menu > Transform > 'Align to Custom Orientation'. Now the objects' rotations are aligned...

... you can send the cursor to wherever you would like to snap the left object's face to, and snap the helper to the cursor..

..before AltP un-parenting the left object with 'Keep transform', and deleting the helper.


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My Blender model has invisible insides when exported to unity
I have a crate that I got online and then customized and animated to open and close, and in blender the walls are visible on the inside, but in unity where I imported them they aren't, can someone please tell me why?

OR, you didnt flip the normals in the inside of the box
Select the faces that are inside, click CTRL+N and in the tool window tick the box that says INSIDE

Maybe it is invisible in Blender also.Have you switched on Backface Culling?
If it works with this then you can add planes inside or you can solidify the external faces.


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Inconsistent pose when exporting rigged model to UE4
I'm having a problem where when I work with my model in Blender its pose is equal on both sides, but when I import to UE4 it gets this weird inconsistency in the left arm that rotates and lifts it in a weird way. Is this common? Is it something wrong I'm doing in blender, or UE4? Is there a quick fix for this? There is one simple idle animation attached to it, if that makes a difference.

Thanks.

Do you have keyframes?

I've responded to this post twice but was having computer problems, sorry. But yes, I do have keyframes.


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Rig not moving in keyframe mode, bone locations turned green
I did something that I thought was just putting in another keyframe for one of my IK bones, but not when I move to another keyframe to adjust the rig, it will not move the mesh. There's a keyframe marker on the timeline.
(I think that's what that yellow diamond is) and the bone locations on the left have turned green.
What does this mean and how do I get back to moving my bones?

your problem is not clear, could you please share your file? https://blend-exchange.giantcowfilms.com/  green means these bones have keyframes but not on the current frame

Consulting the docs https://docs.blender.org/manual/en/dev/editors/timeline.html confirms that the yellow diamond is indeed a keyframe marker.


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Why can't I move my transform widget in Blender
I am new here and I was following an online blender tutorial. After I followed every step, I cann't move the transform widget to the direction I want. I am stuck here and I don't want to jump to another video until I understand everything.
Please help me.
Thank you in advance

It's not a cursor bro. It's a gizmo. Click on the tip of the arrow and it will let you do things to your object. Right click on 2.79, left click on 2.80

It's a dummy that is centered around the object.

Transformation Manipulators


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Make an Object not reflected by a Surface?
I want to make an Object which cant be seen on Reflective Surfaces, for example: Metal. I want to make it so that if I Place the Object over a Reflective Material, it should not be seen on there.
How can i make it so the Surface doesn't Reflect my Object?
Thanks in Advance!

you could deactivate Glossy option or in the Properties panel > Object > Cycle Settings, but it won't be reflected by any object, I don't know if you can make it reflected by some objects only

If you're rendering in Blender-Render, select the object, go to it's Material properties at right, open the Options tab and untick "Traceable". (or vers 2.8 equiv)

You got to add your render engine to the tags, please.

You can do this with the Light Path Shader Node.
EDIT: Do note that I what I posted works with the default settings in cycles, but EVEE reflections behave differently so it might not be the exact same.
FOR CYCLES:
Here is a basic shader setup that prevents reflective surfaces from seeing your object. In fact it prevents it from casting any reflected light at all.
You can turn this

Into this

By using this Shader setup Involving the afformentioned Light Path Node.

You can read more about the Light Path Node here but the value you are interested in is the "Is Reflection" value.
Long story short, things that have light reaching you only as a result of reflection from other objects (in this case the underside of the ball) are flagged as "reflection" rays by this light path.
For reference:
This shader setup works by using the mix and transparent shader nodes, driven by the light path. If a ray is a reflected light path, it has a value of 1 being put into the FAC value of the mix shader. This makes the mix shader choose 100% of the SECOND input shader.
Non reflected light gets classified with a 0 in FAC therefore it only chooses 100% of the FIRST input of the mix shader
You can use this effect to for example, make reflections semi transparent if you replaced the second node with a translucent shader instead of a transparent one or you can put a complicated node graph to use in place of the reflection while leaving the original directly viewed object as its normal shader.
This is especially interesting if you plan to do NPR (Non photo real) renders etc.

Just uncheck the Glossy ray visibility mark in Cycles settings for that object:

This turns the object into vampire and won't be reflected from any glossy surfaces.

Considering that the object can have shadow or be emissive, we would possibly want to avoid this (which shows shadows on the mirror and cuts the emissive on the cube outside of the mirror):

This setting intercepts all these effects so that it is totally invisible from the glossy plane above, but all its properties stay visible outside of the glossy plane:

The node setting is set so:
If the ray depth is more than one (for reflective light and shadow) but not if this is a diffuse (we want the object still emit or cast shadow in non reflective space), or if this is a reflection, then we set to transparency.

If you're looking for more precise control, you can place transparent planes in front of glossy surfaces and use nodes to turn them into makeshift masks.
To do so, simply use the Transparent Depth output of the Light Path node in the object that is being reflected. Then, based on how many times the glossy ray has gone through a transparent plane, we can make adjustments to the shaders accordingly, either making the object disappear (as Spancs requested above), or many other possibilities.
In the below instance, we have no transparent planes in front of the left-hand mirror, one transparent plane in front of the middle mirror, and two transparent planes in front of the right-hand mirror... and use the Greater Than operation to adjust the object's shader accordingly:


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Pen won't sculpt in blender
I've just started using blender. At first, my XP PEN was able to sculpt just fine using its pen. Now, however, the pen suddenly doesn't work when sculpting. The tablet recognizes the pen is there, as the mouse follows it. I am also still able to select buttons using the pen. I cannot, however, sculpt. When I use my mouse, I can sculpt just fine. Simply the pen will not work. I do not believe I altered any settings.
How can I fix the issue?

Are you using rechargeable pen? Is it recharged? Have you installed the tablet driver?

Yes my pen is charged and functional in every aspect -- other than sculpting. For some reason it won't sculpt, but it can click on buttons just fine. I do have the latest driver. I'm very confused as to what is wrong.


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How can I bake the physics cache of linked objects?
Imagine you have a rig that consists on bones and everything, and that in that setup you also include curve objects to do some physics simulation. All these rig objects would be part of a group for linking
How can you bake the cache of those physics when you link the group in the animation file?

Yes this can be done.
However the solution is admittedly awkward, and this is an areas Blender could be improved.
Initial Bake

Make sure the point cache has External and Use Lib Path option enabled,this way each library object can have its own cache when instanced in other files.
Now for the trick In the file that links this data in.

In the Properties Space, Select the object category.
Pin the object (Pin icon, top left corner of space).
Now, you can use the object ID selector to select a new object, one that is in the library and need the simulation to be baked.
Now navigate to he buttons and run the bake operation.

Note, This is really a hidden feature which we are not proud of!
Setting Parameters
To just execute the bake locally often isn't enough, you probably want to change the frame range and may even want to tweak physics settings based on the environment.
In this case the only option is to use a Python script which overrides these settings on load, give it a name that won't conflict with other Python modules and enable Registered in the text header so it runs on load.
Heres an example: my_init.py
import bpy
scene = bpy.context.scene
obj = bpy.data.groups["MyLinkedCharacter"].objects["HairDo"]
obj.particle_systems["ParticleSystem"].point_cache.frame_start = scene.frame_start
obj.particle_systems["ParticleSystem"].point_cache.frame_end = scene.frame_end

This script can be run manually at any time to update the settings.

Note
Rather then having single text-blocks per-file, the open-movie Sintel used a single Python script that loaded for all files, called finals_config.py. I'd recommend using a single script to manage this otherwise you can't easily see whats happening without opening up every blend file although this script become messy over the course of the project so its not a great starting point, more a reference as to what can be done.

You write: "Use Lib Path option enabled", but answer below tell disabled.

I just found solution ( it is same as above, but for me much better for understand :) )
If you go to the Object properties in your linked scene, there's a dropdown menu that allows you to select objects. Make sure the cloth object is selected. It'll have an L next to it indicating it's a linked object. Then you can click the little pin icon which will pin the object selected in the dropdown menu to the properties panel even if you select another object. Now switch to the Physics tab with the cloth bake settings and you should be able to press Bake.

This was a bit confusing. Thanks for clarifying - added your image to own answer.

VERY IMPORTANT NOTE
1) The "Use Lib Path" must be disabled, otherwise the cached files will be written for the linked source at the source blend file path, as opposed to what should be, which is per scene file at the scene file path.
2) After Caching the linked file, save the main scene file, go to where it's saved, right-click on the cache folder and make the folder and all its contents "Read-Only". If you don't, Blender deletes them one by one when you scrub the timeline (for reasons unknown, at least to me... :-/)
3) Then, it's safe to send the file to a render farm and whatnot...
AJ


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Editmesh: Toggle between all edge-loop boundaries when selecting?
Does anyone understand what Campbell means when he describes this new tool function?
https://developer.blender.org/rB276ef3b3b5192aad5c3e5e02c69246

Description
Editmesh: Toggle between all edge-loop boundaries when selecting
Now Alt+RMB,RMB will select all connected boundaries.
There are times when you just want to select an entire boundary loop
  ignoring face topology, previously there was no way to do this.

I've tried several models with different topology and Alt-RMB, RMB does not do anything beyond what I would expect.  I also tried releasing the Alt before clicking the second time but that does what we've always come to expect.
Well anyways, if someone has some thoughts on this matter, please shed some light.

It selects connected edge loops which are not connected to anything else (boundary edges):

This only affects cases where the loop is on the edge of a non-closed part of the mesh. For example, if you try this on an extruded grid (with thickness), nothing will happen as there are no boundary edges on a manifold mesh.
It should also be noted that this doesn't seem to work with Shift.

What version of Blender are you using? I can not make it work in 2.70 (hash: 19e627c).

@maddin45 You have to use a version later than the commit mentioned in the question. The latest buildbot should have it.

I've just started reviewing questions I've posted which have no Accepted solution.  It seems this one slipped by.


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Particles Emitted Far Away From Emitter

As you can see, there are particles being emitted that aren't even close to the emitter object (underneath the rocket). They are several blend units back and down. Does anybody have an idea as to what's happening? Let me know any other info I need to put.

Here is my particle System settings

Please show your Particle System and Any Forces and Obstacles.  We see the flow only in the image in your question at  this time.

@atomicbezierslinger I have uploaded my particle settings, and there are no force fields at the moment

Show the emitter mesh in Edit Mode.  With all vertices selected. Keystroke A. Isolated vertices will not render typically, thus they can have some subtle effects, They  can produce particles. It is quite possible you have a stray vertices.

Get a fresh start, if your particle system is not too complicated. Delete your current emitter mesh to reduce the possibility  of stray vertices.  Emit from faces rather than vertices.  Faces are more visible. Use a circle or bottom of cylinder.


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Aluminum Foil Texture
I'm trying to make the Payload Adapter Fairing of a Falcon Heavy rocket, which has a foil texture. I like what I have so far, but I think it could definitely use some work.

This is my node setup for the material, using an image of foil I found online.

This is the result I got; it looks a little better with good lighting, but the bump is still visible.

Here is the reference.

Could we see the normal map you are using? Considering that aluminium has a pretty consistent surface color, I think this entire effect could be done with displacement. Also - reflective stuff tends to look alot better with a full lighting setup/hdri.

@GiantCowFilms no normal map, I used one image and set it to bump and texture

@cegaton done there is a refrence

Seems like you should be using normal (bump) and distortion mapping with a solid material color.

@Sparrowhawk Well, technically you used it to generate a normal map. Using actual displacement would produce much better results: https://blender.stackexchange.com/a/71110/3127

NICE :-) I tried to do somthing like you at airbus, and it's very hard! I tried many different textures, scanned and with camera picture. Paper, aluminum fould and cling film din't worked, by now, I'm trying to scuplt it. Because MLI (The Satelite foil) hase a certian stifness, which is very hard to simulate!

Try something like this: use a distortion modifier and maybe some normal mapping and ditch the image texture all together.
Using this technique has the added benefit of being more realistic and because it's not BGE the performance shouldn't suffer too much.

I used displacement modifier, thank you for the tip. However, I used a texture other than the distorted one. Many thanks :)

but the problem of that texture, like I already use is, that it looks too flat, and also that there are areas which are completly flat. The charatacs of that foil is also, that the creases are note randomly, the follow the strucute below.

I think it's realy important that you put the matalicness all the way up. this would mean that the matrial is treated like a metal witch makes it way more realistic. after that you can just use the map you are already using as a bump map. and than you can play with your roughness and specularity and see what you like.


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Weird artifact in blender render

I'm trying to recreate a spa water bottle, to get some Blender practice. An example of the bottle:

Around the bottle are some round carvings. I created these with a Difference Boolean with a torus. I've hidden these torusses (tori?) from the view and renderer.
However, when rendering (with Cycles Render), I see some weird shape, like one of the torusses isn't really hidden. When looking with the rendered viewport shading in 3D view, I don't see the extra torus (which is what I expect).
What could this be?
Modifiers applied to the bottle, in order: subsurf, 8 booleans, solidify.
The rendered view (with unwanted artifact):

The viewport view:

EDIT:
I've doublechecked all modifier visibilities and the visibilities of the torusses themselves, and I don't see anything odd. See the image below.
Additional info, I made the torusses by extruding a circle over a circular beziercurve, and creating a mesh from that.
EDIT2:
I've added the Blend file to the top of this question

Restricting viewport visibility (hiding) and restricting render visibility are different things. In the Outliner, uncheck the camera icon to hide your torus in the final render?

Both all 'eyes' and 'cameras' are unchecked for the torusses, so they should be hidden in the viewport and renders.

Are viewport and render visibility the same for all of the modifiers?

Yes, the viewport and render visibility for all modifiers are the same. See the post, I updated it with a screenshot at the end.

Can you provide the file to play with? Atm nothing indicates what could be wrong. Looks like the Boolean might work with viewport settings but fails for denser render geometry (subsurf at start of stack). And with Booleans failing you might get those results.

Please provide the .blend-file

@JaroslavJerrynoNovotny & Gimli: I've added the .blend file, see the top of the question.

The problem is caused by a small discrepancy between how the booleans are applied on a level 3 subdiv and a level 4 subdiv. Drop your render sub-div level down to 3 or move the torii so they create the correct behaviour with level 4 subdiv enabled in viewport.

Thank you, didn't think of looking at the subsurf differences for render and view. Do you have any idea what causes this issue with the boolean, and how to possibly fix it (except for lowering the subsurf)?

It seems to be a bug in the boolean modifier, when using 4 subdivisions, the top torus 'cuts' the geometery instead of taking out the section it needs, which seems to be stuffing up the face normals making the second torus do what looks like a 'union' rather than a difference.
https://ibb.co/mL96zJ

I have found making slight changes to the cutting object (torus) such as the thickness or position often fixes bugs like this. Unfortunately sometimes it doesn't just work as it should.


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UVProject why no detail in the cusp surface image?
I have UVProject working... projecting an image on a flat surface extruded from a cube. But when I repeat this on the cusp surface (see image) it becomes a diffuse color ie no detail of the image. I imagine this is because of the extreme complexity of the cusp surface, is there some way the cusp surface can be treated to accept an image, and eventually a movie clip?

Hi, @Denis, can you show us your settings, (Material and Modifier).. or perhaps, more simply, share your file, following the instructions  on https://blend-exchange.com/

I checked your file. The cusp surface don't even has a UVMap. What did you mean on UV projecting?

So how would I reproduce on the cusp surface what is working on the flat plate ie projection of an image or video?


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Flag Behaving Unexpectedly
I have a flag waving in my blender file. The other flag is working perfectly fine while this one is showing unexpected behavior.
The cube is on 385.4 on x-axis. Also, I've already tried to add another plane and change the existing one, but it shows the same abnormal behavior. In the original file I had 65 of them. 64 of them are working perfectly fine except for this one.
Here is the blender file:

Hello Talha.. this looks like a slip.. Cloth > Shape > Pin needs to be set to the vertex group:  'Group' . Unlike @Taio, I didn't bother to figure out why it wasn't flying.. I just Shift-D copied over  the working flag to the right place, modifiers and all, and reparented it.

Yes, it solved the problem. I actually did a lot of things so forgot to change it back to 200 but could have figured it out. Thanks.

The flag Plane.063 has two different settings.
First, it has not its pin group set which will hold the flag in place. Select Plane.063, go to the Physics Properties panel and then to Cloth > Shape > Pin Group and set the vertex group Group. Now the flag will stay in place but not wave due to the wind settings.
Second, in the same panel, go to Cloth > Field Weights > Wind and set this value to $200$ (thats the value from the working flag Plane.064. The flag should wave now again.


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How to continue extruding Bezier curve
While shaping a Bezier curve it allowed me to continue a smooth curve giving me 3 handle points at every vertex, however at the end, when I try to extrude it, it loses its curve and goes completely straight. What’s the fix?

Select the control point and V > Aligned?


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cycles rendering is too dark
This problem has troubled me for a long time. When I render the object under cycles, it will appear black and dark. No matter whether I adjust the light source or HDRI, I can't make it have a uniform color.But I once created an object that didn't turn black, and I forgot how I did it.

You seem to have overlapping particles. Maybe that's some sort of z-fighting.

u are right! thank u!

The object has two vertex groups, 1 and 2 and you use them for distributing the particles and adjusted the Number of particles to the amount of vertices in the according groups.
However, group 1 has 6304 vertices, but 3143 of them are duplicates. Which means, there will be two spheres instanced in the same location, which results in Z-fighting as @MartynasŽiemys already suspected.
Group 2 is even worse, it has 15812 vertices, and while in some locations are double vertices, there are even somtimes 8(!) vertices in the same place.
So to ged rid of all the duplicates go into Edit Mode, select all with A, then M > Merge > By Distance. A message at the bottom will tell you that 15785 vertices were removed.

Now you can check the groups how many vertices they have left and set the values in the particle systems to these numbers, group 1 has now 3161 and group 2 has 3170 vertices.

Merging the vertices alone will not make the spheres look correct, because the number of particles matching the old numbers will now lead to doubled spheres even though the duplicate vertices are deleted. But when you use the new lower values in the particle systems, there are no longer dark shadows caused by Z-fighting:

thank  u so much

@DanielRadin You're welcome. If this solved your problem please consider accepting this answer, read more about it here: What should I do when someone answers my question?

thanks! got it!


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How to hollow complicated inner surface?
I am conducting research on salivary gland bioprinting. I have developed a solid structure of a 3D model representing the salivary gland, and now I need to create a hollow inner lumen within this structure. As a result, the thickness of the wall will not be uniform, as the size of the lumen may vary as it approaches certain areas. I am wondering if there is a method or tool available to create a complex hollow inner surface, as the solidify tool can only achieve simple hollowing.

Can you give us a clue about the general characteristics of your outer model? Solidify can have variable thickness, controlled by vertex group. That can be painted in, or controlled by texture. You can model / sculpt the inner surface, (perhaps initially derived from the outer surface) independently.  How you do this partly depends on the final purpose of your model. (Illustrate with an image?)

Sure!. If you google salivary gland morphology the first picture that looks like a hand is what my outer model look like. The lumen in the picture is what I am trying to create. Here is the link in case you can't find the picture: https://anatomypubs.onlinelibrary.wiley.com/doi/full/10.1002/ar.23569#:~:text=Defining%20the%20Morphology%20of%20Adult,90%25%20of%20the%20total%20saliva.

Hi, Kay.. Nothing labelled 'Lumen' in the illustration. I take it that's the lining. Do you need the cellular structure represented? Just the surface, or the side-walls, of cells? Is this for illustration, or for 3D printing?


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Cycles render problem: overexposed edges
I believe that the problem is in render settings, but I am not sure. I tried to reduce/change light power, but it does not help.
Help me guys!

This is the material:

Hello. It looks like subsurface scattering, almost like your material is made out of flesh. Can you post a screenshot of the shader node tree ?

Sure! https://imgtr.ee/i/d76Tz

Yup, definitely subsurface. You need to reduce the values coming into the subsurface color by a lot, they are counted in Blender units (or meters if you're real-life scale) so a white value means that subsurface rays will traverse 1 m into your mesh (not exactly though, but I think it's a good enough explanation)

Related to @Gorgious comment: How to use Subsurface Scattering


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How to create an infinite plane in cycles?
I have already found one similar question, however it doesn't correctly address what I am talking about.
Please see this, example to know exactly what I'm talking about.
I have only found this, and this, but both use a curved plane to do the trick, which would work unless the object is to be rotated(in animation) to view from every angle.
Yes, again we could rotate the object instead of the camera but, what about a large array of object, that would really distort the scene and setting the camera accordingly would be very difficult.
Setting the camera at this angle would be good even for a large array of objects:
, but what if we need a more acute view like this:
 , (even if we set the world background color to white this would be impossible to actually blend if taking the lighting into account, as it would emit light and the edges of planes would be visible.)
I don't know if there is a workaround with the lightpath node with this to only make the area where the shadow falls visible.
And I don't know how to take only the shadow information into the compositor to make this?
Primarily focusing two problems:
1) how to make such a world in cycles, infinite, only the shadow information and the object?
2) How to make such a world in cycles, infinite, only the shadow information and the object and a slight gradient in the infinite world?
Therefore, I resolved here.

Imagine real world sitaution where you make photoshots for advertisment. Let say it's beer can. Do you rotate whole photo studio with it or just the can? If you don't care about light changing around object (when using HDRI) you can always rotate back plane with camera.

For that case you don't really create infinite ground plane, rather than setup adjacent world background and composite object with its shadows and the rest with nodes. See http://blender.stackexchange.com/questions/17877/how-do-you-create-an-infinite-ground-plane and http://blender.stackexchange.com/questions/518/how-to-make-a-model-cast-shadows-onto-the-world-texture-background/

Mr Zak, that would give me a gray background and objects on top of the shadow would be masked

It's not really possible to create a truly infinite plane in blender, but such a plane wouldn't help you isolate an object on a uniform background. Even an infinite plane still has a horizon.
Shadow Catcher
To isolate an object (with its shadow) against an arbitrary background, what you really want is a shadow catcher. This is an object which renders as alpha transparency except where shadows fall on it. With a large plane acting as a shadow catcher, we can easily render transparent images with shadows. Using an alpha-over node in the compositor, any background can then be inserted with ease:

Cycles doesn't quite have this feature yet, but development on it is well underway and a working version (used to produce the above image) should be in development builds soon.
Unless you care to compile blender yourself (it's not as hard as it sounds!), you'll have to wait for a little while yet to use this.
Bent backdrop
If you just want to mitigate the distracting contrast of a hard horizon, perhaps a backdrop with a bent bottom section such those used in studio photography will do:

See What is the fastest way to create a curved plane? for a wealth of techniques to create such a shape.
For your case of a turn-table animation, you could rotate the model itself, or, if you wish to keep the lighting constant relative to the model, you could orbit the camera around in a bowl-like shape:

Perfectly reflective plane
If you create a diffuse ground plane with a color (albedo) of 1, it will reflect all light that hits it. Provided the only source of light near the horizon is the sky, then it will reflect exactly the same amount of light as the sky emits, resulting in a seamless transition:

Compositing tricks
Using a combination of renderlayers, the shadow pass, and general node trickery, you can probably come up with something which works pretty well in your case. See the following questions for some examples:

Using scenes and render layers to composite an object isolated on white background with shadow
Render shadows over a transparent background in cycles
How to create a shadows pass in cycles?
Shadowless render pass
Cycles: Shadeless "Shadow-catcher" Material for Rendering onto Footage

I wish I could give more than just one upvote.

The shadow catcher is a part of blender now, see this tutorial https://www.youtube.com/watch?v=lXJca9D_TRM


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Emission material won't work while another emission in my scene is on
I'm having trouble with an emission material that refuses to emit while another material in seperate object is emitting. In the attached screenshots you will see that the emission from the lamp wont work while emmision from my neon sign is on. Can someone tell me whats wrong? Thanks.

Have you tried turning on multiple importance sampling for the small light?

It's on do you have a recommended setting?

It's an issue with object size, basically it seems like Blender can't find your lamp filament.
Actually the emission is still working, only it's influence is being disregarded because it can't be found easily. In theory with an unpractical amount of samples it would eventually become visible. If you increase the number of preview samples to an insane amount the light will actually start to become visible in the form of very spaced fireflies.
The Cycles rendering algorithm is having trouble finding your very tiny light source (lamp filament) when there is a comparatively very big and bright light source around (neon sign).
My advice to you is that it's not recommended to use such small light sources, hidden away behind so many layers of glass, as actual means of lighting up your scene.
Fake the light coming from the filament, and add an actual lamp object in its place instead to actually light up your scene.
Also see https://blender.stackexchange.com/a/65171/19307

Thanks for taking the timeout to answer my question. The answer is very helpful and much appreciated. Thanks again!


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blurry textures on fullscreen in blender game engine
So I made a basic scene composed of point lights and a plane to test my textures in the blender game engine along with a basic fps camera.
the problem that i have is when i play the game using the embedded player, textures look fine (diffuse, normal and specular), when i use the standalone player it works fine too but when i use fullscreen mode in the standalone player the textures are the only thing that looks blurry. i tried changing resolution, using diffuse texture only, updating blender but non of that worked.
Im using GLSL shading btw
this is how its supposed to look like:

but in fullscreen mode (using the standalone player) it looks like this:

(the monkeys are there to see that the blur does not affect game objects, only textures).
does anybody have a solution, it would be really helpfull.

thanks.

Is the result the same if you disable anisotropic filtering?

if you are talking about the settings like the ones on this post's answer: http://blender.stackexchange.com/questions/6683/how-to-get-anisotropic-filtering-in-blender-internal
i dont have those settings

It looks like you have "mip maps" enabled in the sampling settings for the texture.

can you send a screenshot, i cant see where it is.

I did a short experiment. It looks like the lower mip-map level starts as twice as early in full screen compared to window at the similar resolution (due to the border it is not the same at my system).

You need to activate anisotropic filtering in Blender's system settings.
Hit Ctrl+Alt+U, go to the System Panel and change the settings under Anisotropic Filtering to 2 or higher.

it was already on, i set it to max and it didnt fix it. the problem might be the same as in this article's answer but i dont have those settings, can you help?

@WalidLaribi - not without the file to work with. You might upload it to http://blend-exchange.giantcowfilms.com/ and add the given link to your question.

here is the link for it:

I just tried your file and set the anisotropic filtering in the system settings all the way up to 16. Looks good that way - aka visible difference. Other than that there's nothing wrong with your material settings.

yeah i see the difference as well, but there is no difference when playing with the standalone player @metaphore_set

This effect does not look like anisotropic filtering or that it change anything. It looks more as that in full-screen the generated mip-map level is shown earlier than in window mode.That is all.

Try:
from bge import render

render.setMipmapping(2)
render.setAnisotropicFiltering(16)

On my system these settings do not show up in the game engine unless they are set through the python API.


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Using two keyboards with Blender
I have two keyboards and would like to use keyboard #1 as usual and keyboard #2 mapped in another way. Is this possible? Currently the two keyboards are considered equal.
If this is not possible in Blender, is it possible to hack Windows so that e.g. Q on keyboard #1 emits a different character or modifier code than keyboard #2?
Possible use case: I have a separate numeric keyboard, and would like to use key 1,2,3 instead of MMB actions for pan, rotate, zoom, as the MMB button push or drag is really damaging my hand.

Were you able to figure it out?


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Hide backface with xray and object wire mode?
I'm doing retopology and find it convenient to turn on xray for the object I am building. However, I now see ngons facing away from me as well. It's hard to navigate.
I would also like to set the display type to wire (like in image below). This way the original mesh isn't hidden and I can easily create new geometry around eyes, nose and mouth without hiding them.
I guess a mirror modifier could help along the x-axis since I can eliminate that half of the mesh. But I would like it even better if I didn't see the back of the skull when working on the face.

I found out that I missed the latest release and that this feature was in it.
For future reference, here is how to do it:

Turn on X-Ray, located under under Display in the Object panel.
In the 3D view > properties-panel (N), under Shading, check hidden wire.

You may also fin this add-on I made useful : https://github.com/ChameleonScales/Backface-Hiding
it hides the backfacing or non-visible geometry to address the issue of Backface Culling not hiding mesh components in Edit mode (vertices, edges, faces).
Here's a comparison between the built-in Backface culling and the Backface hiding from this add-on when doing retopology on top of a high-poly mesh with X-ray enabled on the low poly mesh (click to enlarge):

Note that it works in wire mode just as well (except for the "Hide non-visible" button)
More info in the readme of the github page.

Create instanced copy, set that to in front.. hide backfaces
Here in first 2 minutes I show that:
https://www.youtube.com/watch?v=MeWTLwXr2VQ&t=13s


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Volumetric fire looks cuboid

I do not know why. The tutorial I followed was https://www.youtube.com/watch?v=D_ybn4tYxs4.
I am not able to get the result of a nicely shaped flame.
Below is my set up for the domain:

You have brightness set to 1 on both of your bright contrast nodes, it should be 0 as you don't want to modify the brightness at all, increasing the brightness like this is effectively setting the background density to a value above zero, so the whole cube is being rendered.
In fact you don't even need those nodes at all
The other thing I noticed is the top attribute node should use the density attribute for the smoke, rather than the flame attribute.
In order for volumetric materials to render correctly you will also need to go to the light paths section of the render settings and set the number of volume bounces to something reasonable.

henlow, I have tried this again with the bright contrast nodes removed, but my flames died.
https://imgur.com/a/RtLLA18
I am not sure what to do anymore

@lala Try plugging in just the emission shader to the volume output and see what you get

Still dead flame. Would you like me to send my file for you to inspect?
[link]https://i.sstatic.net/wx23p.png]

@lala sure, that would make it easier.

here ya go https://drive.google.com/open?id=1RE7-TEOMjem_NcHoK-v1uv3GOfHXailr

@lala, other than volumetric bounces, I can't see anything wrong. You simulation isn't baked so it was empty when I opened the file. You may want to bake it or replay the animation from the start of the timeline and check in solid shaded mode to make sure that the fire simulation has actually been generated. Moving the simulation objects to a different layer and just showing that can also help with just rendering what you are trying to get working (https://docs.blender.org/manual/en/latest/editors/3dview/object/properties/relations/layers.html)

holy mama, i clicked bake an it works. but why?

@lala blender doesn't save the results of simulations by default, baking is how you do it. Baking essentially saves and freezes the result of the simulation so blender won't need to, or try to, recalculate it. Also feel free to click the tick next to the answer to show that it was the solution to your problem.


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How do I set weight painting brushes to limit total vertex weight to 1?
I'm using Blender 2.8!
I was wondering if there any way to set the weight brush so that if a bone controls a point (or group of points) with a strength of 1, it will automatically remove the strength influence on the point from other bones to 0?
In my line of work, no point should ever have a weight value more than 1. So things like two bones affecting a point with a strength of 1 should never happen.
I keep seeing this nightmare on tutorials where they have to guess which bone is affecting their vertexes and manually remove the influence from all other bones aside from the one they want to controlling the vertexes.
I was just wondering if there was another way.
Thank you so much for your time!

The auto-normalise setting in the brush menu will make it so the total weights on any vertex that you paint are adjusted to sum to 1. This has bee in blender for a long time, see https://docs.blender.org/manual/en/latest/sculpt_paint/painting/weight_paint/tools.html.
The menu options is here in 2.8:

Thank you!!! Wow, I swear none of the tutorials on YouTube went over that. Much appreciated!

@GoodNight click the tick button next to the answer to show that this solved your problem.

Oh! Ok, did it!


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Creating Glass - What am I Doing Wrong?
I've followed all the tutorials, tried so many different things. But changing the transmission to 1 just makes the shape go grey. I've turned on refraction in the light settings and nothing has changed.

You are wanting to know how to do glass in Evee?

Maybe it's grey because there is nothing to reflect. Try the same setting in 'look dev'

You need to turn on the Screen Space Refraction both in the Render panel

and in the Material settings

I generally use a Glass Shader and a Transparent Shader. Then use a Mix Shader to join them before giving the Material Output.

The transparent shader reduces the realism of the scene: it should be used only for windows or large objects to reduce the noise in the scene, and always combined with the *Light Path node


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I Can't Create a Face from Several Circles
Just like the problem appears in the image, I want to make a face triangulated around all circles. Instead, a face is created that overlaps everything I selected. What its the technique to join all of these faces? I tried fill, bridge to edge loops, and make face, but it's not turning out how I want it to be.

This is something that cannot be done in one press of a button or a click of a mouse. You will have to go through and manually create the faces you are wanting. To get triangulated faces, try making them first with quads and then use a Triangulated modifier. Or, if this does not suit you, you can do it manually. If you think about why this is happening for a bit, you should be able to understand why you are getting these results.


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Boolean Modifier not working at all
The Boolean Modifier isn't working at all, just leaving these weird lines:

Possible duplicate of Boolean Modifier not working

https://blender.stackexchange.com/questions/5140/cannot-execute-boolean-operation-when-subtracting-several-spheres-and-cylinder/5148#5148

I tried both solutions and none of them worked

It looks the bit where the intersection occurs is non-manifold (a single plane), if so this is probably the problem


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My baked maps are glitched
If i bake a map the colour of the parts are red and black or pink and black.

Do you use multiple materials? Have you added the baking image texture node to all of them? Do you have multiple objects or UVs sharing these materials that could overlap on the UV space?

Hello, maybe share your file?

https://drive.google.com/file/d/16dguqrFBY7Yvh7izOTCtIjQX_vm1DCrB/view?usp=drive_link thats the blender file if thats is what you need

that's it but your link asks for an authorization, could you please fix that or use another platform?

Does it work now?

You can use https://blend-exchange.com to upload your blend file to your question or provide more detailed screenshots on your material baking set up.

Hello, Imagineniv .. welcome to BSE. Could you flesh this post out a bit, with details of what  you are trying to bake .. diffuse color.. combined.. etc, ? That would tell us more about why the monochrome image is unexpected.

If you're trying to bake the diffuse, it won't be possible if you are using Metallic in the Principled BSDF

iam using metallic in one of my mapsbut the other one with wood texture has the same problem.

i tried removing metallic from the Principled BSDF but it didnt work

I don't know how Combine is supposed to work but he Diffuse works fine: https://zupimages.net/up/23/43/9tsp.jpg

i dont know what i did but if i do just the difuuse it doesnt work. Can it be a problemwith the pc ? bECAUSE i even tried with file i uploaded but it doesnt work.


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Make object not have effect on ambient occlusion
So here is my problem, i have a  displaced plane textured with a material that uses ambient occlusion in it in the form of the ambient occlusion node as a factor in a colorramp, for simplicities sake, i'll say my material is just the colorramp and ambient occlusion plugged into the material output. now i want to use a particle system to spread an object across the surface (let's say a cube). but when i do that the material becomes very dark since the particles effect the ambient occlusion. is there any way i could make the particle (cube) not have any effect on the ambient occlusion? i don't want to have to lower the distance or effect of the AO, i'd like for the cube to have zero effect on the AO.
Thanks in advance!
EDIT: using eevee

Does the 'Only Local' checkbox in the node do that for you?

no, unfortunately not. i'm using eevee btw, should have specified.


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How do I make an object not enter another one?
I am currently learning blender and I started doing this damn donut, I've tried many times and one of the problems I'm having now is that when i grab the top icing and pull down it enters on the donut, how can i solve this? Also, the edge of the icing drop don't seem kinda soft. sorry I'm still learning :)

TL;DNR: Use Shrink/Fatten to increase the icing size; only move vertices in the Z plane; use Shrink/Fatten to decrease the icing size; and use a solidify modifier to give the finished look.
The only way you can prevent that if you are doing something similar to how Price teaches that tutorial is to grab the vertex above the one you have current selected and pull the vertices away from the donut.  If you're just trying to randomize the border of the icing to make it look more organic, here's a technique I would use instead:

Separate the icing from the donut and make it another object as he does in the tutorial.

Select the "icing" object and enter Edit mode.

Use the Shrink/Fatten tool to make the icing bigger (Shortcut Alt–S and move the cursor.  Left Click to finish.) Don't overdo it. You just want it far enough so that it's easy to do the next bit.

When you move the vertices using random proportional editing, restrict the motion to the Z axis and don't go far enough to drag a vertex "into" the donut.  (To constrain the movement use GZ as the move command)

Use the Shrink/Fatten command to reduce the size of icing so that it is just enough above the surface of the donut so that the solidify modifier that you apply next will leave a reasonable thickness for the border.

Add the solidify modifier and set the size so that the icing penetrates the donut.

Use a Subdivision modifier to smooth out both the donut and the icing; and give them both subdivision modifiers and smooth shading

omg thanks a lot it really helped, now it's fixed (https://prnt.sc/KOvQ0MdGukXs)

You're very welcome.  There's nothing wrong with Price's approach, but this one just happens to work better for me.

From your image, the distance between the loops is too much. Create a loopcut between the last loop and the preceding loop and scale it up a bit using the shift button.


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Procedural fire - scaling and similar shape on both x and y axis?
This is fire, generated as a procedural volumetric shader:

Viewed from X axis:
from Y axis:
How to get the fire style/shape from x axis to appear on the Y axis as well?
Also, how do I scale up or down this procedural fire without affecting the shape or style of it? Wanna fit it under the cylinder I added later on in the attached blender file

Hello, Francis, Thanks for the link ... I think it's fair to ask you to give us a clue about how this flame is generated.. (e.g. a node-tree, if relevant?) before asking us to commit to a download.

Yes, this flame is node generated: https://i.ibb.co/GnXWQM2/kurumii.png

What you do exactly mean with: "appear on the Y axis as well"? Do you want the volumetric effect to be symmetrical in itself?

Yes, I'd like the Y-axis volumetric effect to appear like how it does on that X-axis

If you set these values for the scale, the fire will look the same from both axes.

thanks, this worked.

Also, does anyone know how I can scale this flame without altering the appearance?


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Animation of a teardrop with Geometry Nodes and Simulation Node
I'm trying to make the fall off a tear.
I use geometry nodes with simulation nodes.
What I want is that the first hundred frames the tear drops little by little.
And from frame 101 the tear falls fast.
Instead, the tear falls slowly all the time.

My Geometry Nodes

Where is my mistake?

pos will never be increased/changed...so the switch will always be false. I think what you might want to compare is the "real" position because this would change. But honestly if you want it to be dependent on frame, you should also work with scene time - not with values from a position or an offset

i am not sure whether you know a programming language - if yes, this might help: a named attribute is nothing else then a variable in a programming language. You can read or set(change) it. But you never change the POS value.

Thanks Chris your comments are very usefull. I will change the way I do. I will store the inicial position of the tear and compare it to the actual position. If the lenght between the two vectors is greater than X I will move the tear quickly otherwise I will move the tear slowly.


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How to set active control point of a curve using python
I'm failing to set the active control point of a nurbs curve using bpy.
For context, I'm trying to add a hook to a selected pose bone. The following snippet demonstrates the idea. A pose bone is already selected:
ob = bpy.context.active_object
curve = ob.data.splines[0]
scene = bpy.context.scene

ob.select = True
scene.objects.active = ob

bpy.ops.object.mode_set(mode = 'EDIT')
bpy.ops.curve.select_all(action='DESELECT')
curve.points[0].select = True
bpy.ops.object.hook_add_selob(use_bone=True)

This returns the following error:
RuntimeError: Error: Requires selected vertices or active vertex group

Related https://blender.stackexchange.com/questions/81395/python-set-active-face-batch-unwrap-follow-active-quads

Thanks for this. There's no equivalent 'active' property on the collection of spline points. bmesh isn't applicable because the curve is not a mesh.

Also, there's no applicable operator under bpy.ops.curve.


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How to combine two objects? Blending a face into an apple?

I'm trying to add two objects together, one being a face and the other being an apple. I have it all lined up so I can put them together but I can't edit more than one object at once to do so. Is there any way I can edit these both at the same time or combine them into the same object?


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Why is my model so dark?
I'm working on texturing my model and have been previewing the render. I have a light in my scene but my model is really dark.
Here are my nodes for the material.Am I doing something wrong? (I'm using cycles btw)

is your light strong enough? have you tried with another object?

Using a cube beside my mesh it still is just as dark. I have a sun right beside it though.

It looks like your bump mapping is not proper. Your output of image texture(normal map) node which is yellow coloured is connected input of bump mapping which is purple coloured and this is not good. Try replacing the Bump Mapping node with Normal Map node and also try recalculating the normals.

At the start of the question I pointed out that I have a light in my scene but it isn't doing anything to my model

yes it can be the bump, perhaps try to put your image output in the Height input, you can also share your file

It looks like flipped normals.

The Normal Map Image node was plugged into the wrong input. It was in normal but height appears to have fixed it. Thanks to moonboots2 for the answer.


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Growing animation that’s super specific and weird
So I have this model of an Apple that I’m going to (hopefully) use in a game. For movement I’d like to have an arm on its top. I’d like to have an animation where the arm grows out of the top. I know about shape keys and I didn’t think they would work since you can’t add vertices in them. If anyone has any ideas on how I would accomplish this it would be greatly appreciated.

you already asked the question I think. Not sure about why not shapekeys? You could also scale the bones in Pose mode...

I’m still super confused on how I would use shape keys to do that. Is there any way you could explain a little more?

the default cube has 8 vertices, if you subdivide it a few times it has many more vertices but it will render exactly the same. Create your arm fully grown with a many vertices as you need and set it as a Shape Key. Then move all the vertices so that the result is the un-grown arm. Even if the the un-grown arm has significantly less detail it will still have the correct number of vertices and can be used as a Shape Key.

Or use two objects, apple and arm.  Have a hole in apple where arm grows out. Shapekey on hole to open close.

@WhimbleThimble you know, an apple with a growing arm on it top "for movement" is not a very understandable concept... please add some more detail, maybe a screenshot with some marks (eg: using blender's grease pencil) showing a bit what you wish to achieve. As rob said above, shape keys could help you but you must have all needed geometry from the start, since shape keys can only transform existing geometry, not add or remove it.

I'm not sure what you mean with your arm growing on the top of your apple, but here are the two solutions I was thinking about (quickly made):

Either you do it with Shapekeys, building a progressive growth with at least two positions. To make this you have to begin with a flat apple in the first shapekey, then add the rest in the following shapekeys.
Or you do it with an armature and just scale up/scale down the bones of your arm


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Rigging a Wheel to Turn Corners: Drivers vs. Bones
The tutorials I've found show how to rig a wheel to roll automatically, in one direction (X or Y), in relation to the location of an empty or bone. I've managed to get the wheel rotation to work along both the X and Y-axis in a drivers-based rig, but the wheel rotation when steering on the Z-axis isn't always accurate.
A bones-based rig could possibly work if there's a way to set the axle or driver bone to local space, but I don't see a way to do this, and it might just result in the same issues as the drivers-based rig.
Your thoughts and suggestions would be appreciated.
The two rigs I've made are downloadable here, both controlled by the "ground" empty/bone.

Both approaches will not work when dealing with corners, they will only work in straight line. There is more about why that is here:
Making wheels spin as car moves
You need to either:

construct a path for the car (or for each wheel if you want to be precise) and drive the wheels with that
Use Animation Nodes addon, this lets you access animation F-curve data and compute the wheel rotations
Use rigid body physics to simulate the wheels and collision with ground, bake the simulation into keyframes
Create a PyDriver (a driver with added function through script that can access blender f-curve data) or a frame change handler. With both you can access animation to compute the path and drive the wheels correctly
Write a script for your rig that will add/update animation of the wheels to the f-curves, similar to a script that would snap FK and IK bones in a rig, but with different function
Write an own engine that will simulate the wheels collisions and add it through app-handler to execute on each update of the car rig

Thank you very much for the information. I think I'll try the rigid bodies approach first, and then explore the other approaches if needed.


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Crossing in geometry nodes
Have anyone idea how to do a crossing in blender geometry nodes?I've made something like below but don have idea how to make faces in geometry nodes Thanks in advance.

To be more specific I'd like to add red triangles for every vertices which has more then 2 neighbors like on picture below

What exactly do you mean by "do a crossing"? What exactly should the mesh topology look like in this case? Can you show a concrete example of this?

Yes, result is marked on image red mesh. Something like that https://www.youtube.com/watch?v=FRJl0uAnMZU


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Pattern in Blender geometry nodes
like on picture below. How to do this kind of pattern. It is made by star and next row is number of star points divided by 2.

"...next row is number of star points divided by 2" ...I honestly can't really see that here. According to which mathematical principle should this be built? Is it only about the edges, or should this be a mesh with faces? Or should these be curves? Please tell us more, show what you've tried so far so we don't have to figure out the whole solution for you. Thank you!

Hi thank You for comment. It should be mesh with faces. I will do more precise image please wait...