text:
Where is Add / Subtract button on sculpting in Blender 2.8
Sorry for the silly question but I'm having trouble finding those button on Blender 2.8. If anyone knows this, could you post screenshot of it or tell me where it is..?
P.s: I'm editing this since this has been identified as possible duplicated of another question. I'm not looking for ctrl button to change add and subtract. I wanted to know where the add / subtract button has been moved in Blender 2.8

Possible duplicate of Is there a shortcut to switch between Add and Subtract brushes, in Sculpt mode?

On the right in the Tool preferences, you can find them there.

Thank you so much! I was wondering where it is.


text:
Animation of a person sitting down
i am quite new to blender.
i have a person which should sit down to a "chair".
The Person is rigged (has bones and so on) but if i go into animate and move the bones (and the person object) and insert frames, it doesen't move at all. It always shows the last pose.

okay, i edited it. sorry

or do i have to something else in the beginning of the animation? did i forget anything?

okay i found the problem.
in the bottom toolbox "Scaling" was selected for the keyframe insert...

If you are happy with your solution, it's good to mark your question as answered

source: Stack Exchange

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

sort: votes


text:
How to scale rigged model and animation data?
I am trying to scale a rigged model. I first import it to blender:

I select the model AND the armature, press S then type 0.03 then enter:

I press ctrl+A and apply all transforms:

As you can see, things get shifted down and the animation points are not on weird spots, this also breaks the animation completely. I go to  the graph editor inside pose mode, select all animation data and filter it by location only:

I press S followed by Y followed by typing 0.03 and enter:

It's clearly broken beyond relief. How do you scale a rigged model such that both the model and the animation data are properly up to scale?

pls provide blend file (simplified if possible) so we can check it out

How do I share the blend file? Stack overflow does not accept that file type?

How to add a blend file

Running into this same problem but following the steps is not working for me. I'm doing a mechanical animation that does not assign bone vertex weights or use an armature modifier. Instead it just has simple meshes parented to bones. Is this still possible to apply similar steps to fix it? Another forum post also led me to this tool which claims it can "Apply armature rotation and scale without destroying original keyframes" https://blendermarket.com/products/godot-aniamtion-tool

There are two ways to deal with this, one simple but incomplete and one complex but complete.
The simple way is to make the mesh child of the rig, then scale the rig in object mode. In this way everything will work as expected, but in a scale different than 111.
The complex but complete method is this:

choose a precise value for scaling (i.e. 0.01, to reduce the proportions by 100).

Check that the mesh is child of the rig in object mode (if not, set the parenting).

Scale the rig by 0.01 in obj mode

Apply the armature modifier to the mesh then apply its scale.

Apply the Scale of the rig

Select the animation, go to graph editor, enble the view for all controls (even hidden ones), in the filter section, type in "Location" so to hide all rotation, scale and every property other than locations.

Set the 2D cursor to frame 1 and value 0, set the 2D pivot point as 2D cursor, select all and scale all location animation data on Y axis only by 0.01 (press S, Y, 0.01, Enter).

Add a new armature modifier to the model, targeting the rig

If the rig is a simple FK only rig (like Mixamo) generally to scale location data of hip (master) bone is enough.

Whenever I apply scale to the armature by doign ctrl + A and then selecting scale the model shifts down by 50  meters and all the animations break. THe same doesn;t happen with location or rotation.

It's because of the fact that you have to scale animation data too: if a character which is 2 meters tall is standing at 1 meter from the origin, when you scale the character by 0.01 it becomes like a 2 cm tall character standing in a location which is 100 times far as it should. When you scale animation data too, everything comes back in place as expected.

How do I scale the animation data?

It's written in my answer, points number 4 and 5.

I tried following the answer in the specified order, but I must have done something wrong.

You forgot point 5 (2D cursor as pivot point). If still not working, please upload the file.

You were right I forgot to select that, thank you so much.

Try scaling them down, then applying the scale.
To apply the scale, select 1 object at a time (in Object Mode) and press Control + A to open the Apply Transforms menu. Choose Scale from the popup.

I seem to run into the same issue when I read the data, the translation portion of the gltf nodes is still set t the original dimensions.

When i do that the model snaps 50 meters below ground level and the animations become broken.

the scale is being keyframed, hover over scale and clear the keyframes

Just clear the Scale keyframes of your rig, adapt to desired scale and hit apply scale

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


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UV Mirroring after UV Sculpting

How do you mirror one side to the other topology after UV sculpting?
My object already has many shape keys. Is there a solution other than how to apply the mirror modifier?

there may be another solution but mine would be to delete that side of the mesh that has old uv, mirror your object with mirror modifier and new mirrored part will have this same UV you created... but that only works if your model is symmetrized at this moment


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How to display all contents of a Date Modified column in Blender's File Browser

As you can see in the attached image, my blender's file browser doesn't show all the contents of the Date Modified column. There seems to be insufficient space to display all the content. I tried hovering the mouse cursor over the pipe symbol between columns, but the file browser didn't seem to provide an option to resize the columns. Is there a way to show all the contents of a Date Modified column in the blender file browser?

As Gorgious and Gordon Brinkmann speculated, the theme was the cause. I'm a Blender 3.2.0 user and I've tested all the themes and the only thing I found is the Modo theme causing the problem. The rest of the themes show all the contents of the Date Modified column. I opened up all the panels to see if the Modo theme had any effect on the File Browser options, but there were only color related options.

Why does this only happen with the Modo theme?

I noticed that the Modo theme changes the Widget Points value in the Text Style panel.
Other themes default to 11, but the Modo theme is 10. If you change this value to 11, the contents of the Date Modified column are not omitted.

What version are you using ? On my end it is automatically expanded and even goes over the file name when the popup window is resized. You seem to be using a custom theme, maybe there's a setting in the preferences ?

I would suspect that, too. Or before looking for a setting in the preferences, could you simply switch to a default theme to check if everything's visible? I use the builtin Blender Dark for example and I don't experience this problem.

This should be a Bug. It's better to report it in bug tracker.

Reported: https://developer.blender.org/T99207


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How to use different types of data blocks for driver variables?

I know that the content of text can be registered through a user-defined function and entered in the Expressions box.
But how can I use text as a data block for variables, as shown in the image?
Blender's UI allows such manipulation, so I just wondered how to use it.

Of course, Transform Channel, Rotational Differences, Distance were not available in the text. Single Property seemed possible.

but when I checked my text through bpy.data.texts['Text'].keys(), by default, the text did not have any properties.

I tried this.

And it worked but I do not think it's a very useful use.

Blender also allows you to use many other types of data blocks as variables in the driver, other than text.
This may mean a lot of freedom to writing a driver, but I've never seen cases that uses data blocks other than objects or armature as variables for the driver.
If you know any good ideas or examples, please share them with me. Thank you.

Hello, for information what is your end goal with this feature ?

Yes, there is no clear goal, but I would like to understand more about how to use the blender driver variable.

Then could you rephrase your question so it is more focused ? I'd very much like to help you but I can't pinpoint what you are asking for

I'd like to know various examples of making drivers using more different types of data. I revised the title to reveal my intention a little more.

Make a test driver script to see what works what doesn't.
Using textblock as a driver variable target was going to be an other suggestion re your question on bringing in a text datablock when linking.
Re Text blocks
Speculatively at issue here is drivers use evaluated scene objects, and text objects don't get evaluated... a custom prop may not update in the driver if animated.
>>> eto = D.texts['Text'].evaluated_get(C.evaluated_depsgraph_get())
>>> eto
bpy.data.texts['Text']

>>> eto.is_evaluated
False

A simple test driver
To fiddle about with drivers I often make use of this little test script

Use use_self to pass the evaluated object. \

Can pass all driver
variables as as locals()

Generic test script.
import bpy

def test(*args, **kwargs):
    for arg in args:
        print(arg)

    return -1 # a simple val to indicate working

bpy.app.driver_namespace["test"] = test

Now set up a driver and test the test.

The driver is on object "Circle", the text object evaluates to None as do most. However the matrix world of the cube object is passed.  As is the depsgraph the driver is using to evaluate the objects.
<bpy_struct, Object("Circle") at 0x7f1cb1372e08, evaluated>
{'text': None, 'var': Matrix(((1.0, 0.0, 0.0, 0.0),
        (0.0, 1.0, 0.0, 0.0),
        (0.0, 0.0, 1.0, 0.0),
        (0.0, 0.0, 0.0, 1.0))), 'depsgraph': <bpy_struct, Depsgraph at 0x7f1cbeb80108>}

Adding a rotate driver on cube, the console shows updates the values for both viewing and rendering animation
Now from the matrix world it appears we have all the transforms of the Cube object in our driver in one fell swoop.
The ideology of a driver is to return an int or float as the value of the driven property. Will find however can make this driver a "pseudo" copy transform constraint by adding before the return statement and re-running driver.
args[0].matrix_world = args[1]['var']

which using better names is self.matrix_world = cube.matrix_world   If say the x location is being driven by this, then it is given that value and all others are taken from the matrix world..  This is abuse of the driver system .. but hey it's fun.
Some answers using drivers
This one adds drivers to drive material index of each face of a mesh
https://blender.stackexchange.com/a/183716/15543

Amazing insight. The idea of a driver, the test of what works, is what I wanted to hear. The driver variable fields are so open that beginners like me are puzzled. But now I realize that many data types are not given a clear use, but rather use depending on a user's ingenuity.

A great lesson in how to get under the bonnet. :)


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How Can I Create a Sculpt Mask Based Purely on Face/Vertex Selection, Instead of By Manually Painting It?
This question gets asked from time to time, and doesn't seem to get any attention. Here's one of the more recent instances: Converting a vertex group into a sculpt mask
I find it frustrating that the only way to create a sculpt mask in Blender is to manually paint it. This is needlessly imprecise in some situations, such as when there are already skeletal deformations in play which put various mesh parts too close together to get the brush between them to create the mask. Sure, you could return the armature to its rest pose, but some sculpt edits will require the new pose to be preserved, for the sake of reference.
Given that it is much easier to select  multiple sub-elements (face/vertex/edge) precisely than to paint surfaces precisely, I would think there is a way to choose the former approach over the latter.
Is there?

I'm not great at sculpting, but what you can do is:

Select faces in Edit Mode.
Go to Sculpt Mode and from the Face Sets menu choose Face Set from Edit Mode Selection.
Enable Options > Auto-Masking > Face Sets.

Now the Face Set is masked and your sculpt only affects the mesh outside of the mask. Maybe there is even a better way, I don't know if vertex groups with weight paint can be used for masking in Sculpt Mode, perhaps someone else can step in here. If so, you can set the weight according to the selection so this should also do what you want.

That works, but seems a bit fiddly for requiring the extra step that demands a face set be created after already having selected the faces. It also leads me to wonder what face sets are even for. They surely must have other uses than just creating masks.

Another issue, too, is that when using face sets, the mask behavior is different from what I am expecting. So long as you begin your stroke outside the face set, it is ignored as expected. But if you begin your stroke inside the face set, it is affected and everything outside of it is ignored. This could be desirable functionality, depending on the situation. But it should also be possible to ignore the masked region no matter where one is clicking. So far, all the options I've explored have not shown me how using face sets to create the mask can allow me to always ignore the masked region.

@R-800 About the extra step: I guess from selecting faces to a mask there will also be an extra step necessary even with a different method. A step that says "make mask from selection". Well, as I said I'm no expert in sculpting. I would usually use a mask to prevent me from accidentally sculpting where I don't want to sculpt, so I'm most of the time not starting my sculpt inside the mask. Of course that's not exactly how a "real" mask should work, at least you can use it with selected faces. But that's why I'm hoping someone else would come up with a better solution.

I made an addon to do just that.  I agree it is kind of stupid having to do it that way.
https://blenderartists.org/t/kraynes-tools-free-addon-for-blender/1493222.  It is the first module and first button on the tool panel
it works by using "fill mask."  Right now it is kind of wonky in 4.1 but it should work fine in 3.6+.   I know this method is klugy, but I am working on a way to more directly set the sculpt mask from selection.

For people interested in a scripted version.
This will set every selected vert of the active object to the 'mask_value'
import bpy
import bmesh
import numpy as np
obj = bpy.context.active_object
bm = bmesh.new()
bm.from_mesh(obj.data)

#get selected verts
v_sel = np.empty(len(obj.data.vertices), dtype=bool)
obj.data.vertices.foreach_get('select', v_sel)
sel_idx, = np.where(v_sel)

#get custom data layer paint_mask
mask_layer= bm.verts.layers.paint_mask.verify() #strange way, but that gets you custom data layer
bm.verts.ensure_lookup_table()
#set every selected vert to mask_value

mask_value = 1.0
for idx in sel_idx:
    bm.verts[idx][mask_layer]=mask_value

bm.to_mesh(obj.data)

Thanks for the script, works like a charm! There's a little typo in its third line, though: "nummpy" instead of "numpy"

wow, it works :)

It appears that using the mask brush will also obey face sets, as long as the Face Sets and/or Face Set Boundary are selected when painting the mask.

By enabling this, you can paint a masked area constricted by the face set. If you then disable the face set auto-masking you will have your typical masking behavior (where your brush obeys the mask no matter where the stroke starts).
This could also be useful for temporarily combining multiple face sets without destroying them.
I sympathize with OP that it would be great to have a "create face sets from vertex groups" option, but that doesn't account for the fact that vertex group selections can overlap while face sets cannot.


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Why the baked normal‘s color looks different when it's color space assigned as non-color?

Why the baked normal‘s color looks different when it's color space assigned as non-color, and it is identical in sRGB space. It seems like been appilied a 0.454? gamma curve onto it when the color space is non-color. I really know little about the normal science. And this might not be a big issue for the image can be saved in a normal look. If someone can give a quick answer I will be glad. Did I make a mistake in baking?


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How to distribute objects ONLY on vertex groups in geometry nodes?
Thought this would be easy but have been struggling so much with this.
I have created vertex groups (indicated with red color) on a big terrain plane and now I'm trying to distribute objects only inside those areas. I tried adding the vertex group in the Density Attribute but it seems that it's using the weight of the group and it does not have a hard edge so the objects are leaking outside of the area.
Any ideas how to achieve this easily?

OK It's the final edit. I promise
This method works in blender 2.93 Alpha(I don't know about version 2.92)
All you have to do is set the density attribute to material_index and voila your work is done, no weight paint required, it assigns density on the basis of material used.
Screenshot:

It looks like yours has a higher level of subdivision.  Vertex weights are interpolated along faces, you can see OP's plane is yellow-green all the way to the edge.

That's why I asked for the blend file

Right now it;s just guess work

Yes I think so too. I would really like to keep the geometry really simple as in the actual project I don't want to add extra geometry just to achieve this :(
Here is the blend file https://pasteall.org/blend/d21aed04db79463d992d9504ba0fd93c

I edited my answer. Read it. Hope it helps

I appreciate your help but unfortunately increasing the geometry is not an option in the actual project file where I need to have less geometry for easier manipulation of the planes. Increasing geometry is more like damage control as there will always be overflow of objects, even if it's smaller with more geometry.
I hope there is some completely different workflow of limiting the areas using vertex groups but I'm surprised it's not more obvious.

Hey, it's me again, I gave your last comment some thought and I found an alternate solution that does not require increasing geometry. I have edited my answer for you again. Please read it

Hey Maulik! This solution is a bit hacky as I can only target that one difference between materials, but it actually works great for my needs in this project! I can confirm that it does not work on 2.92 but works great in 2.93 alpha! Hope they will add some solution in the future to easily target vertex groups but meanwhile this solution works great! Thank you so much for your help!!

Hi, material_index is not the only attribute that you can use. I told you about it because it was the easiest to implement in your case. You can also use crease attribute, it will apply density based on the crease of the vertices or you can use  UVMap(In ur case, u will have to delete the old UV map and create a new UV map by only selecting the required faces and unwrapping it). And these are some of the many attribute you can use.


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Displacement modifier doing weird things to different meshed
I am using blender 2.92 and it does not seem to let me control displacement on my mesh. Let me explain, let's take cube for reference

I subdivide one of it's sides and create a group from the vertices of that side
I apply a displacement modifier and insert image I want to do displacement with in the properties panel
In the modifier panel I set the coordinates to UV and set the vertex group to the one I chose in step 1
split the screen and turn 2nd screen to UV viewer where I adjust the pattern. As you can see this is what it looks like in image 1.

First image is how I edit the pattern and second is where I see the outcome.

Now here is my issue, I do the same stuff for a more detailed mesh but I use remesh modifier and this is what I get

There is no frame of the mesh in UV viewer as opposed to the first image. The mesh is a fair bit more detailed and I am not sure how to get the UV view to show me the deconstructed mesh. The method does work for the mesh though as you can see in image four.

When I try using remesh for my cube instead of subdividing the side I get the same results as with the heart mesh, I suppose using remesh modifier could have something to do with this. .
The 5th image is showing the mesh before remesh modifier is used. I am trying to create a 3D texture which will be felt when the piece is 3D printed. Sorry for the long explanation, hope you guys know how I can get the mesh to show up in the UV side of the screen.
I have added this image for Nathan about UV projections.

You're not showing any UV mapping on your heart.  Does it have a UV map?  Is it a meaningful UV map?

@Nathan I have updated the post and mentioned about remesh modifier. Yes the heart does have a mesh before I use remesh modifier. This seems to be an issue with a remesh modifier I think.

I don't think you know what a UV map is, which suggests that's what your problem is.  Select all verts of your heart in edit, u-> project from view, take a look; change perspective and repeat.  You're using a UV mapped texture, so you need to specify how it maps by creating/editing the UV.

Please use paragraphs and proper spacing in your posts so they are easier to read

@Nathan thanks. I did what you said and it started appearing but the selected vertices I have projected turn out to be in a slanted configuration. See the image I posted

@user121012 Yes, there are a few billion different ways to map your UV; I wanted you to start to see what UV was.  You need to learn how to map UV by either watching some tutorials or playing or, preferably, both.

@Nathan The mapping did not change the way the displacement looks as can be seen in image 4. I will definitely watch tutorial videos, 100%. So, you think this is a UV mapping issue? If I figure out that it should solve the issue?

@user121012 Yes, it is due to UV, and you need to learn how UV works.


text:
How to export line/edge to svg?
I am exporting a very simple scene to svg via the svg addon, this is my scene:

And this is the output:

My issue is that I want the line in the center to be visible (and dashed when occluded). I have tried toying with the edge marking features but no luck so far.

This is the svg add on I am talking about:

Is this a special version of Blender? I opened it with 3.6.2 and trying to hit render to see what it looks like crashed my Blender. And even worse, my other opened Blender project was still open, but when I tried to save it it crashed, too... so I'm sorry, I cannot help you with that file... oh, Blender completely refuses to open now, have to restart my PC. What kind of file is that?

The SVG add-on? There are quite a few SVG add-ons for Blender.

@GordonBrinkmann That sounds strange, it's just a blend file, exported normally through the UI. Are you sure it was the file that caused it and not something else?

@MartynasŽiemys I added a screenshot of the add on

@Makogan Well, it never happened before I tried to render your file, it did not happen when trying to render anything else after I restarted my PC and did not touch your file again... but I made several attempts to open your file and it always crashed when I hit F12, so I may not be sure but I have a strong suspicion. //Edit: I dared to open it again, it only happens when I render in Eevee, when I switch to Cycles everything is fine. But Eevee works on my PC in other projects.

@Makogan Okay, my last insight on this issue with my PC and your scene: when both Freestyle SVG Export and Freestyle are enabled in the Render Properties, it crashes when rendering in Eevee. But not if only one of these options is enabled, no matter which. But no problem in a new default scene, only yours. Strange. Sorry for this excursion.

@GordonBrinkmann it might be that I have it set up to only export to svg? I am also on linux, no idea if  that might affect it.

I am sorry - this is not a solution. I hope someone will come up with a real answer to your problem. This is just an explanation why you do not get it to work in the first place and what other problems there are with Freestyle.
Unfortunately you cannot create what you want with Freestyle, or at least not really in a simple way. The main reasons you'll find in the Blender Documentation on Freestyle's Known Limitations:

So the first thing is, your edge will not work in Freestyle because only faced mesh objects are supported. Now you could extrude the edge to create a face, and if you mark only one edge as Freestyle Edge and use Edge Mark in the Edge Type settings this might have been the way to go...
However, there comes the other limitation: "No edges at face intersections are detected yet" - and what the problem with this is I'll show you with an example. I've set up a thicker line for the visible edges and a thinner dashed line for the hidden edges and have two objects in my scene. Rendered separately, everything looks fine and as expected:

Now when objects are in the more or less same location, they are overlapping each other. The larger object hides a lot of the smaller object, which also hides a bit of the parts lying behind it from the camera's view. What you would expect to see is something like this on the right side:

But unfortunately, since _Freestyle is not very good at detecting which edges are visible and which not when faces are intersecting, the actual result you'll get is this:

So here is what I did with your file, I extruded the edge just a little bit to have a face and marked one of them as Freestyle Edge:

But due to the limitations of Freestyle, the result does not look as if the edge was going through the planes but as if it is completely behind them:

And if I had made the extruded face larger, although only one edge is marked as Freestyle Edge, rendering it now would make it even worse because the face would still work as an obstacle hiding the edges of the planes:

All in the only way I see right now is somehow splitting up the edge in several parts and trying to find ways to make everything visible the way it is supposed to be. But as soon as you would be going for a different camera angle you would have to adjust all again. Or you have to render the parts separately and create the correct visible/hidden segments in another software. The best would be of course someone knew a better way which makes it all work automatically the way you want.


text:
Blender baking is absolutely black after exporting and re-importing mesh
I have a mesh that I modify through scaling and then bake, the result looking like:

I then exported it as an obj and re-imported it. But when I try to bake it again I get:

The meshes should be identical. So I am not sure what could be causing the second to be rendered black.
It also takes no time to "Bake" the baking bar appears for half a second showing 0% and then disapears. As if blender considers that it's not worth baking the object.
Edit:
Working:
Not working:

Please edited your question and add the .blend(s): https://blend-exchange.giantcowfilms.com/


text:
Particle system not rendering, emitter rendering see-through
I need to motion track a fireplace to some footage. Everything looks fine in the render preview, and even in the viewport, however the actual file that renders doesn't have a fire, and the emitter is see through looking.

The photos are of the render itself, and the render preview.

Can you post your material setup for the fire domain in your original message. Most of the case the material was not setup correctly

Second thought is to check on how your render layers are configured. Can you please attach your blend file?

I added the material setup (I think?) but i couldnt figure out how to add the .blend.

Sorry if this sounds dumb, but are the nodes not what i just added? The very first picture?

Alrighty, i believe i added it now.

Thank worked! Thanks a lot for your help! Aside from looking cheesy, everything looks great. Thanks.

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


text:
Optimization ( More cuts or stretching )
I want to make a house model but I am not sure which method to make walls for rooms would be better.
Dragging around already existing edges that have no other purpose, but which are still necessary in the mesh to create a proper edge loop, resulting in a messy mesh but with fewer triangles and vertices.

Or cutting up the mesh which would result in higher count of vertices and triangles but edge loops would look nice and tidy

It is unclear what your concern is. Could you please edit the question to clarify your goal? Thank you. :)

Also walls of text are not welcoming for readers trying to help, please use proper spacing.

Why not make walls as a separate entity? You wouldn't even have to deal with all that funky topology, and end up with a lot less polygons overall

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


text:
Understanding how "vertex of corner" works in geometry node
I've this test case which starts from a simple mesh made of two connected faces, captures the face indices then instanciate and realize a grid on each initial mesh face centers.

After that I'm testing how to sample information on the initial mesh from each point of the realized instances.
This information is stored so that I can see the result in the spreadsheet.
The initial mesh has the following face and vertex indices (vertex 3 is at 0,0 and vertex 0 is at 1,2):

Now the sampled values which come from the node group in the setting:
If I sample the face corners locations, all is good as we can see here:

But if I sample in the point domain using "vertex of corner" node, I've a result that I was not expecting:

What am i missing?
The final goal is to be able to get the vertex normals from the face corners as they are different from the face corners normals.
I presume I can also capture all that before instancing, but I wanted to avoid storing too much data.

This part of the documentation may be the key point, about "sample index":

If the Geometry used for the input is the same as the geometry from
the field context, this node is equivalent to the Evaluate at Index
Node. Using that node is usually preferable since avoiding the
geometry socket makes the whole setup easier to use in other
situations and share.

But the doc doesn't tell explicitly what is happening when the contexts are different.

The way I see it, the source geometry has 6 vertices. The destination geometry has 8. The 'Index' input of Sample Index is the destination index. 2 vertex-indices in the destination are unaccounted for. (And in the other case, even though the count is the same, you're lucky the corner indices match.) But..  this stuff scrambles my head, so I could be wrong.

@RobinBetts hi. I don't know if you gave a look to https://blender.stackexchange.com/questions/291926/how-to-subdivide-triangles-into-four-triangles-with-geometry-nodes/292198#292198. In fact this is the same principle, except for "vertex of corner". That's the point....

(Phew!) @Crantisz has said it :)

Then you are using Fields (dashed lines) you should know, that data flows in opposite direction. Let me show you. I will mark two different meshes in your setup (splitted and not) with 2 colors:

Splitted geometry (that you get after realize instances) is yellow, original is blue. As long as you see solid lines, data will flow directly from left to right.
Now the data Geometry nodes starts to collect data by using Fields, nodes will be asked in backwards direction:

Going inside group nodes:

Sample Index is quite different node. It can transfer data from one geometry to another. Here is the data flow that shows the flow of original geometry (blue):

The node that I marked by blue, has 6 points, 8 corners. But all data flows in yellow lines initiated by the splitted mesh, with 8 vertexes and 8 corners.
This is that you are probably missed.
btw, you can replace this set of nodes by split edges node:

Hi and thanks. I don't get what you call "splitted" here? I mean I see the yellow marks, but why are you calling it "splitted" ?

You have original mesh: 6 vertices, 2 connected faces, 8 corners, and "splitted": 8 vertices, 2 disconnected faces, 8 corners,

@lemon Usually you do the same thing by adding a Split Edge node. So I called that splitted mesh=)

I most likely need to think it another way. But why is it working as (I) expected without "vertex of corner"?

FYI my goal was not to split the mesh, not at all. It occurs here that the instances have the same shape, but this is not the goal. And if you test that with smaller grid instance, we still obtain original mesh locations

Here I applied the exact same principle https://blender.stackexchange.com/a/292198/19156 the only diff is that I did not need to go to vertex from corner, but only corners informations. So if there is a difference, this is the goal of my question: undertanding what differs.

I upvote your answer. Though, if it is correct, what is the mean to sample (sample index) a geometry using other context than its own context? That seems unlogical to me.

@lemon it shows correct result at first example because both models (original and not) have the same count of corners. By accident indexes of corners corresponds, so you get good result. But then you go to vertices, 8 doesn't map to 6, so this doesn't work anymore

ok, understood. thanks a lot.

Starting with geometry:
Vertices: [(1,2), (0,2), (1,0), (0,0), (1,1), (0,1)]
Faces: [(0,1,5,4), (4,5,3,2)]

The indices of vertices defining faces also tell us about the corners. We can confirm the order is the same (the above order I took from Python API), by using a viewer:

For example The first 4 corners belong to the first face, and then corners # 4,5,6,7 belong to the 2nd face, so the corner #7 is the last corner of the 2nd face, as we can see above the last corner is associated with vertex index #2, and the vertex index #2 should have coordinate (1,0), and the position matches:

You pass that geo to Capture Attribute and capture index:

It's pretty straight-forward, you now have an array for faces: [0, 1]
Vertices: [(1,2), (0,2), (1,0), (0,0), (1,1), (0,1)]
Faces: [(0,1,5,4), (4,5,3,2)]
Faces_anon_attr: [0, 1]

Now you convert those faces to points using Mesh to Points, so the mesh data is now:
Points: [(0.5, 1.5), (0.5, 0.5)]  - taken from centers of faces
anonymous_attribute: [0, 1]  - simple copy

You also create a Grid:
Vertices: [(-0.5,-0.5), (-0.5,+0.5), (+0.5,-0.5), (+0.5,+0.5)]
Faces: [(0, 2, 3, 1)]

Now you implicitly convert the grid to an instance, let's call it my_quad, and spawn that Instance on the Points:

Your geometry now:
Instances: ['my_quad', 'my_quad']
Instances_pos: [(0.5, 1.5), (0.5, 0.5)]  - simple copy from points
Instances_anonymous_attr: [0, 1] - simple copy from points

And now you Realize Instances, so the geometry becomes:
Vertices: [(-0.5,-0.5), (-0.5,+0.5), (+0.5,-0.5), (+0.5,+0.5)] - from `my_quad`
       +    (0.5, 1.5)   (0.5, 1.5)   (0.5, 1.5)   (0.5, 1.5)  - from instance pos

Verts ctd:[(-0.5,-0.5), (-0.5,+0.5), (+0.5,-0.5), (+0.5,+0.5)] - from `my_quad`
            (0.5, 0.5)   (0.5, 0.5)   (0.5, 0.5)   (0.5, 0.5)

=

Vertices: [(0,1), (0,2), (1,1), (1,2)] + [(0,0), (0,1), (1,0), (1,1)]
Faces: [(0, 2, 3, 1)] + [(4, 6, 7, 5)] - taken from `my_quad` but offset by domain_size * instance index

Vertices_anon_attr: [0, 0, 0, 0] + [1, 1, 1, 1] - for each vertex from `my_quad` duplicate data from instance.
Edges_anon_attr: same as above
Corners_anon_attr: same as above
Faces_anon_attr: [0] + [1] - same logic, but `my_quad` had only 1 face.

Your first Store Named Attribute is easy:

So you create Face index attribute in Point domain. You're connecting a field from face domain, but I already calculated all possible interpolations above, so regardless when Blender decides to calculate it, it will be the same stuff as listed above as Vertices_anon_attr but this time with a name:
Vertices: [(0,1), (0,2), (1,1), (1,2), (0,0), (0,1), (1,0), (1,1)]
Faces: [(0, 2, 3, 1), (4, 6, 7, 5)]

Vertices_anon_attr: [0, 0, 0, 0, 1, 1, 1, 1]
Vertices["Face index"]: [0, 0, 0, 0, 1, 1, 1, 1]
Edges_anon_attr: same as above
Corners_anon_attr: same as above
Faces_anon_attr: [0] + [1] - same logic, but `my_quad` had only 1 face.

Finally, your 2nd Store Named Attribute (and the logic repeats 3 more times later):

Hopefully my collage is readable:

Iterate over each point.
Context is vert#0 from the geometry described most recently in this post.
Let's follow the arrow in reverse, going to the Group Output, then to Sample Index.
Sample Index evaluates "Index" field. The context DOESN'T yet change!
Again we follow backwards to the "Vertex of Corner"
"Vertex of Corner" needs to evaluate "Corner Index". So again, need to go backwards to "Corners of Face".
"Corners of Face" needs to evaluate "Face Index" field, so again go backwards to Group Input…
Group Input got this field from "Capture Attribute" node, so that's the anonymous attribute we stored in the beginning. But remember: the context DIDN'T yet change! We're still evaluate the new goemetry, we're still on vert#0!
So let me copy-paste the table from which we read:

Vertices_anon_attr: [0, 0, 0, 0, 1, 1, 1, 1]

We're on first vertex, so we read the first value, 0. Now we can go forward on the field, until we reach "Corners of Face" that requested it.
"Corners of Face" now reads "Sort Index" which actually is a constant, for the entire tree evaluation it's just 0.
So "Corners of Face" sorts corners of face#0 by default weights, which I'm 95% sure is index field:
corner#0, corner#1, corner#2, corner#3
Now it takes the first (index 0) element of this list - corner#0 and finally outputs its index 0 to "Vertex of Corner"
"Vertex of Corner" checks which vertex is associated with corner#0, let me copy-paste the relevant table from above:

Faces: [(0, 2, 3, 1), (4, 6, 7, 5)]

So "Vertex of Corner" outputs 0.
"Sample Index" finally got the index. So now it finally CHANGES context to point (vertex in this case) #0 in the geometry in the output socket of the "Capture Attribute" node. It wants to sample the position. Let me copy-paste the relevant array:

Vertices: [(1,2), (0,2), (1,0), (0,0), (1,1), (0,1)]

The node is sampling the first element from this array, so position (1, 2). The context returns to vert#0 of the geometry the "Store Named Attribute" operates on currently, and outputs it to the Group Output.
Group Output sends it further to the "Store Named Attribute"
The position (1,2) is saved for the first element for N0 array.
"Store Named Attribute" increments context to the vert#1 of its left socket geometry and the process continues until all vertices are processed. Then the process is also repeated for next SNA nodes.

Let's analyze the first vertex of N1 node, to confirm the order of sorted face corners:
2'. vert#1
9. Vertices_anon_attr: [0, 0, 0, 0, 1, 1, 1, 1]
10. First Vert again, the value in the anon_attr is 0 again.
11'. In this custom group, the "Corner rank" constant is 1.
12. corner#0, corner#1, corner#2, corner#3
13'. Take the second (index 1) element of this list.
14. Faces: [(0, 2, 3, 1), (4, 6, 7, 5)]
15'. "Vertex of Corner" outputs 2.
16'. Context chnages to vert#2 in the CA out geo.
Vertices: [(1,2), (0,2), (1,0), (0,0), (1,1), (0,1)]
17'. Third element (index 2) is position (1, 0).
The only thing I can add here, is that since "Corner rank" inputs are constants, For each face you will always sample the same corner, therefore 4 first values of each named attribute will always be the same, as well as 4 last values, because you're sampling the same corner, just either from the first or the second face.

More reading:

Combine two position nodes from different mesh primitives inside a geometry node tree
Raycast + Align Euler to Vector. Wrong Hit Normals
Geometry Nodes: What Does Capture Attribute Add to Geometry?
Passing Data Into Simulation Zone

Thank you for the time you took for these explainations, I really appreciate. I've to read again before I can feedback on your answer (as it is late here, that will be tomorrow).

I think the key point is 4. in the last part of your explanation. Though, the documentation is not clear (my last edit in the quesiton). But yes, the context is the key and that works (I think) without "vertex of corner" because the other inputs are not context dependent (constants). But so, what is the solution? Capturing all before "mesh to points"? (PS: in this context "store named attributes" were only here for debug purpose)

@lemon the "evaluate at index" node also changes context, but it doesn't switch to another geometry. The context it changes is it can switch domain or index from currently evaluated context. E.g. For every vertex you can read a position of a previous vertex by connecting index-1 to the index socket. For "Sample index" node, you can do the same, but also connect a different geometry.


text:
Bone parenting without offset using Python?
import bpy

ob = bpy.data.objects
child = ob['cube']
parent = ob['armature']
bone = parent.pose.bones['bone']

child.parent = parent
child.parent_type = 'BONE'
child.parent_bone = bone

I wrote the script above to carry out bone parenting with Python.
The parenting setting works correctly, but at the end, the child object's transformation will have an offset.
How can I achieve bone parenting without offset?

Additional questions about batFINGER's answers.
I tested the script. But I still get the offset. Did I make a mistake?
I recorded two GIF to clarify the question.
In the case of the parenting using operator, the cube's transform is maintained, but in the case of parenting using script, the cube's transform changed.
Bone parenting using operator

Bone parenting using script

After creating an armature, change the bone transforms in pose mode.
Operate bone parenting with cube & bone of armature.
The ops method keeps the cube in place, but the script method changes the cube by the bone transform
I want to achieve ops result using python script.

Result by ops (Ctrl+P/Bone after select cube and armature)

Result by script

Could you please  clarify....  is this a dupe of https://blender.stackexchange.com/questions/112776/parent-object-to-a-bone-and-object-becomes-offsets-how-do-i-prevent-object-from   Answered below based on  my understanding of no offset resulting in child at  the origin of  parent when location is (0,0,0) .  In the link posted OP sees "no offset" as the object not moving when the parent is set.

Set basis and parent inverse to identity.
One of the simplest ways to do this is to set both the basis matrix and parent inverse matrix to identity, to ensure all transforms are those inherited directly.
Getting no feedback re what parenting "without offset" is, have included link to
https://blender.stackexchange.com/a/112856/15543 which has a number of methods to parent, either keeping current global location, (the operator result in question EDIT) or snapping to the transform of the parent as shown here..
The confusion is over the term offset. Code below puts an object at its parents transform with no "offset" from it, no local transforms.
Parenting, while maintaining the object in place, could be considered as setting the offset from child to parent, before parenting.  If turned on relationship lines are a visual rep'n of the parent to child offset.
Code below is same
as 'SNAP_IDENTITY'
import bpy
from mathutils import Matrix

ob = bpy.data.objects
child = ob['Cube']
parent = ob['Armature']
bone = parent.pose.bones['Bone']

child.parent = parent
child.parent_type = 'BONE'
child.parent_bone = bone.name

child.matrix_basis = Matrix()
child.matrix_parent_inverse = Matrix()

Please also notice that the parent bone  setting requires the name of the bone, not the bone itself.

I tested the code and wrote the additional content. Please check.

IMO What is still unclear is which is the one you want. The script posted in link does both.  AFAIC in the new examples given the parent with operator is keeping offset, parenting with identity (as above) is with no offset.

I'm sorry. I'm trying to explain my intentions. I added a new image and work order. Still, isn't it clear what I'm trying to achieve?

Have marked as dupe.

I went to dupe and tried the script suggested as a solution, but the result was the same. The cube doesn't keep its transform and follow along the slope of the bone :(

If you mean my script then change type of parenting desired from  'SNAP' to 'KEEP_WORLD_AND_BASIS'  (Have done this for you   just in case there are more issues) to (as mentioned in the answer  "Blenders default parenting would be akin to 'KEEP_WORLD_AND_BASIS' below") match using the operator Ie the object  not move when parented or reparented.

It works very well now when the code on line 49 is modified from If op == "KEEP": to if op ==" KEEP_WORLD_AND_BASIS":.

The idea is to use op = 'KEEP' for that option.  And take note of different options.  Everything has been explained here and there. The result gif in question is exactly as expected.  The cube, once parented  has no offset from  parent.  As noted here same as 'SNAP_IDENTITY' there.  After running it with 'SNAP' you comment to say its the same as 'SNAP_IDENTITY' above.. once again expected. The answer there clearly states  if you wish to have a result like default parenting use 'KEEP_WORLD_AND_BASIS'.. (reiterated in comment) ...   Please in future read questions and comments more thoroughly.


text:
How 'Remove Selected from Active Collection' feature works?
I thought Shift+Alt+G (Remove Selected from Active Collection) was just a change to a collection.
I read the official manual and understood it.

But in fact, the way this function works in the blender is not only removing the selected objects from the collection to which the active object belong, but also the active object.
Please check the GIF.

What do I misunderstand?
The result I expected was as follows.

Additional Question
If so, how to check the active collection in Blender UI?
When checked with bpy.context.view_layer.active_layer_collection.name, the last clicked collection in the outliner is displayed.

This will also be displayed in the top left of the 3D viewport.
However, the active collection that the collection allocation operations mean seems to mean the collection to which the last selected active object belongs, not the last selected collection in the outliner.
I am curious how to check this active collection in UI.

Solution:
Ah, this was simple and basic.
To easily check the list of active collections to be used in the collection assignment operation, check the property editor\Object tab\Collections panel.

This is functioning properly, but you must understand two concepts:

The active object is one of the selected objects, always
If you remove an object from all the collections in a scene, it will appear as though they have been destroyed, although they are still present in the file memory. It can also still be loaded in another scene's collection.

The way I see it, Add Selected to Active Collection should be relabeled to Add Selected Objects to Active Object's Collection(s). In fact, if your active object is part of several collections, the UI will ask you to which one you want to add the selected objects, or if you want to add them to every one of these collections.
Similarly, Remove Selected from Active Collection should be relabeled to Remove Selected Objects from Active Object's Collection(s). It also prompts the user whith which collection they want to remove the selected objects from.
However, if by doing so you remove one or several objects from their last container collection in the scene, it will effectively disappear from said scene. You can see they are still in the file if you change the outliner display mode from view layer to Orphan data. You can then manually re-add it in your scene.
I agree that there should be a warning if you are removing an object from its last collection saying something like "Warning : This will remove this object from the scene"
To do what you want to achieve in your last set of screenshots, you just have to deselect the cone and call the operator.

Thank you.
I didn't know that the active object was included in the selected objects.
So the way to run the collection operation after deselecting the active object works for me.


text:
How to eliminate transparent line on a rendered textured mesh with solidify
I'd really appreciate if someone could help me with this, it's been driving me nuts.
I've been making a stylized hair mesh with solid a solid texture (purple-ish like the one below) and applied a solidify modifier with a node setup in order to simulate contour lines (I'd rather use this method vs Freestyle). It was all good but then I wanted to add a texture to the hair, like the red one below.

But then when I tried to render the scene using BI, a transparent line appeared between the mesh and the solidify modifier (Note that the previous purple mesh doesn't have that)

Now, when i switch to rendered viewport this problem is not appearing

So if anyone could help in any way it would be much appreciated!
I'll leave the blend file

The textures are not linked to your file. File->External Data->Automatically Pack into .blend

Oops, my bad. Updated File


text:
How to remove bevel artifacts on an unusual edge?
Hey guys I am in a bit of a stump. I am using blender 2.92 and I have an issue trying to bevel an edge near a curve. So see here before beveling  and image after beveling  I could only bevel using the Ctrl + B command. When I use a modifier it does nothing to the edge no matter what options I change. In the second image you can see that there is a bevel but also there are planes sticking out. So if anyone has an idea how to remove those planes. They are probably from overlapping geometry but I don't know how to remove them. The scale of the model is set to 1 also. Thanks.

your topology is bad, it won't allow a good bevel, you need to retopologize

@moonboots if I was to use remesh modifier would that fix the problem?

maybe, you could also try a trick: extrude a bit the large face, then bevel. But maybe share your file so that we can give a try: https://pasteall.org/blend/

@DuarteFarrajotaRamos thanks for advice. I embedded the images. How would you solve this problem?

@moonboots thanks I will give it a go. I also thought to dissolve the faces on the curved side along the curve and make one large face where the gap is and then bevel the edge. Also, thanks for telling me about the trick, so when I extrude the large face which edge do I bevel the extruded one or the original one?

please share your file, it's very hard to guess without the real object  ;)  https://pasteall.org/blend

@moonboots I have uploaded the file. https://pasteall.org/blend/3c9a782d0f2e41129a380e5aa3c3f823

Your topology is a bit messy but you can do that:

First apply the scale of your object, otherwise it won't bevel correctly
Select the big face, extrude:

Bevel, choose the amount of segments in the Operator box (bottom left of your 3D view once you've beveled):

Shade Smooth if needed.

Thanks @moonboots


text:
How to unwrap for detailed face
What I have and what I did:

I have 1 mesh. Now I need to unwrap it considering high detailed head(face). So, I separated head by selection and did unwrap for each one. I got my goal, then I need to join head with body. I joined it and there it is:

So, I pressed Ctrl+A, then unwrapped again, and got this one:

It seems to be okay, but, I lost details on the face. Even if I scale it, it turns green/yellow.
What I need:
When I connect head with body and unwrap it, quads on head turns larger.
I need to get the result like on the first screen, connecting two meshes(head and body), if it is possible, or can you recommend me any ways to go or show me my mistakes?
I tried to use tiles, but didn't get results that I need.
Thanks.

Related: Unwrapping head geometry similar to Epic's MetaHuman Characters?

Thanks, but my problem is: how to connect head mesh with body mesh not losing high detalization on head. I will edit my post.

If you want to have more details on the head then you need to scale up the UV island of the head and shrink down the island of the body. If you want to keep the sizes as shown in screenshots 1 and 2 then use tiled textures (UDIMs).

I scaled up the uv island of the head, but the stretch area turned into yellow colour. I guess it is not good. Also I used tiled textures, the stretch area was orange, maybe i didn't use it properly. I'll check it.

Is the stretching overlay of the angle or area type? Angle is the default. Just tried to resize the face but the color does not change for this type. It does for area and the island turns red.

There is an area, but when i choose angle, it turns into blue. So, do I need to igrore yellow “area” ?

Yes, the stretch overlay shows how much of a difference there is between UV coordinates and 3D coordinates. Area type is good to check that everything has the same level of detail. But you want to have a higher detail on the head and scaled it up. So it turns yellow, later red. That's totally fine. The area type does basically with color what the checkboard texture does with the squares.

You saved my time, thanks a lot.


text:
Anatomy issue, stylized character
I am sculpting this character(Luffy-One piece). I have lots of reference of the anatomy, sculpted a lot, but now I don't see what is wrong and what I need to improve. Can you see it and give me feedback? thank you.

This is the base reference, that I used to start.

the legs look very long, in reality they should be about as the same length as torso + head, but it may be a choice? Also maybe show a side view

Sorry, Now I am not able to show side view, but i added the reference, which i tried to copy. I guess, the length of legs of my character the same as the reference

yes it looks like the original has long legs


text:
png texture with transparent background not properly blending with glass
I’ve been working on this for the past few days and it’s almost ready. But I’ve noticed that when applying a transparent png texture over a glass material and alpha blending it, it is not quite looking good. There is a clear cut edge between the glass and the texture and it doesn’t look good when rendering it. By the way I'm using Cycles. I’ve attached a screenshot below.

here is my .blend file - https://pasteall.org/blend/9b226cf130ab456fbd355b21b16a6e93

Have you tried disabling "Show Backface"? Also, since the glass is "flat", you could probably get away with lowering the IOR slightly.

hello, it is hard to see what's happening, maybe pack the image and share your file? https://pasteall.org/blend/

You can't render multiple transparent objects behind each other with Eevee. This is one of the limitations of the engine.

@FFeller you can if you use alpha hashed.


text:
Missing menu in xyz math extra objects
I am using version 2.9 I have looked at several videos and posts, but do not see this problem.
I lose the menu when using the xyz math functions.
see: https://youtu.be/t_ht2uAW9Lg
Thanks for any help.

It is usually better, and in this way in particular, to provide 2 screenshots of the problem outlined in question (before and after) without requiring others to watch the video just to understand what's the question is about. See general solution on the question https://blender.stackexchange.com/q/7850/1245, also https://blender.stackexchange.com/q/145719/1245. That menu is there only after performing adjacent operator

Here is the answer. Use the F9 key. If you wish you can see the details here: https://youtu.be/cqcHrFmfQLg?t=41

Mr. Zak, yes, you answer basically gave me the information I needed.

Mr. Zak, also thanks for the quick reply.


text:
Blender doesn't update after I change keyframe positions with script
Hi I'm creating a suite of a few small functions which manipulate the position of grease pencil keyframes.
My script works but Blender doesn't seem to use these new values until I click somewhere into the dopesheet.
class GPencilRippleMoveRight(Operator, AddObjectHelper):
"""move keyframes right"""
bl_idname = "outliner.ripplemoveright"
bl_label = "Ripple Move Greasepencil Keyframes"
bl_options = {'REGISTER', 'UNDO'}

def execute(self, context):

    for layer in bpy.context.object.data.layers:
        keyframes = layer.frames.values()
        keyframeCount = len(keyframes)

        if keyframeCount==0: # no keyframes
            continue

        selectedKeyframes = []

        for kf in keyframes:
            if kf.select == True:
                selectedKeyframes.append(kf)

        if len(selectedKeyframes)==0: # no keyframes selected
            continue

        firstSelected = selectedKeyframes[0]

        for kf in keyframes:
            if kf.frame_number >= firstSelected.frame_number:
                kf.frame_number += 1

    # trick to update the display of keyframes in the dopesheet
    bpy.context.scene.frame_current+=1
    bpy.context.scene.frame_current-=1

    return {'FINISHED'}

Just try this code while playing a grease pencil loop, you will see the animation doesn't change until you click somewhere or call a standard operator of Blender like pressing G.
So I guess I need to force Blender to update and use the new values somehow – any ideas?
EDIT:
Ok I found a fix: by switching the object's mode it would update:
origMode=  str(bpy.context.object.mode)
if final_mode == 'EDIT_GPENCIL':
    bpy.ops.object.mode_set(mode='SCULPT_GPENCIL')
else:
    bpy.ops.object.mode_set(mode='EDIT_GPENCIL')
bpy.ops.object.mode_set(mode=origMode)

BUT .... when I loop through selected_editable_objects to use the script on more than one Grease Pencil Object, they dont have the function set_mode.
Is there any other way to achieve this ??
EDIT2: ok it seems toggling .show_in_front also does the trick as do some other properties probably. Now just to find the one with lowest impact.
But if there's is some kind of global refresh of stale data that would better of course.

I wrote an addon with a similar functionality and I used bpy.ops.transform.transform(mode='TIME_TRANSLATE', value=(1,0,0,0)) to move the selected frames. Dunno if that would work for you but it updates the screen automatically.

@wilks . that nudging was my first idea too untill i realized i cannot manipulate the animation with it  while playing the animation (loop). but thanx illl try to use that. does it work for gp and normal keyframes ?


text:
copy and paste object ID to one drive to another
so i'm working on a rig that has a lot of drivers and every driver needs a object ID to function
the problem is that i need to asign my rig to every driver manually

there is a easiest way to do this? like seriously it needs to be a way like when you link the materias to one object to another but i only need the object not the expression and everything else, only the object, once a select my armature the bones are automatically identified so there is no need for that extra step. Thank you for reading

well....you could use python... ;)

There is very little punctuation in your question, and it made it difficult to understand exactly what is driving what. However, I thankfully have successfully applied multiple drivers for something using python, so if you clarify what you were trying to drive, I can work on the code.

hey thank you for you response, every driver you see in the screenshot needs my armature to function, as you can see in the second screenshot there is this red box that needs a object (in this case my armature). as far as i know i need to assign my armature to every driver one by one and is very tedious task so i was wondering if there's a easiest way to do this. the drivers are part of a character. i can give you my blend file if you want so you can see what i mean


text:
Can you access the distance values from the numeric input?
in my Blender 2.92 scene file, you can find the numeric input in the top left corner of the viewport (important, the numeric input only shows when transforming an object). what i'm inquiring about, is the local information displayed by the numeric input. using the cube with a random orientation, i can transform the object a distance of 1 unit along the local y axis ...regardless of the objects orientation, the numeric input will then display a distance value of 1 (or -1 depending on the direction we moved the object) as well as the normalized distance value of 1. although the transform channels themselves update to reflect the objects new world position, i'm actually trying to save that distance value from the numeric input.
does anyone know if this information is stored somewhere? i'm specifically looking to create a custom property that stores the distance values, and it needs to update based on user input in real-time. i'm understanding this as something that could become quite complex to develop from scratch, but the numeric input already shares all of this information in real-time. any insight into this inquiry is much appreciated!

Moving an object in the 3D viewport with a local orientation does not move it in its local axis.  That's doubtlessly confusing, but true.  An object's local transform moves, then rotates.  That's why all three numbers change-- you're not actually moving it 1 unit in its local Y axis, you're moving it in a different space than that.  You can evaluate the motion in some other space, but is that space its rotation on the previous frame, or on the next frame?  They are not necessarily the same space.

the local transformation value is better described as distance. i'm not looking to gather transformation values, but instead am looking to get the distance between it's current position compared to it's previous position. currently the numeric input displays this information, and it's updated based on users real-time input. we can't create wheel rigs without this information unless we create dependencies. in maya we use the expression editor to overwrite dependencies, and those expressions work in real-time just as the numeric input does here.

From the window manager's operators collection.
A very simplistic answer to how to get the values used in the transform translate operator. Other things to consider would be looking for edit mode switches. How to keep track of what objects have context at the time etc
Looking in info area after translating will see the python name of the operator, from which we can get the idname
>>> bpy.ops.transform.translate.idname()
'TRANSFORM_OT_translate'

Make some moves.
Translate 4 locally in $Y$ GYY 4 ,then -5 locally in $X$ GXX -5  and finally 3 in $Z$ GZZ 3
Get the details from python console.
Off to the python console, and get the details of the translations made using operator via UI above.
>>> wm = C.window_manager

>>> for op in wm.operators:
...     if op.bl_idname.startswith('TRANSFORM'):
...         props = op.properties
...         props.orient_type, props.value
...
('LOCAL', Vector((0.0, 4.9, 0.0)))
('LOCAL', Vector((-5.0, -0.0, -0.0)))
('LOCAL', Vector((0.0, 0.0, 3.0)))

Another option is
>>> wm.operator_properties_last("transform.translate")
<bpy_struct, TRANSFORM_OT_translate at 0x7f0df251cb48>

>>> props = wm.operator_properties_last("transform.translate")
>>> props.value
Vector((0.0, 0.0, 3.0))

Your comment indicated that you're not really interested in directional transformations, but only in distance.  You can get this, but it's probably not as easy as you want to get in Blender, because it's a temporal value-- based on values from different frames.
Select your cube.  Animate it however.  Duplicate the cube and make the duplicate non-rendering.  In the graph editor, select all of your duplicates keyframes and move -1 units in the X axis.  Give your custom property a driver based on the distance from your original to your duplicate.


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Must I use Blender 2.8's Shader Editor to Assign Any and All Image Textures?
It seems the answer to the above should be no. Yet after months of use, I still do not know if it is possible to assign image textures (which will afterwards show up in the viewport, and, ideally, also render) without first connecting an image texture node in the Shader Editor. I am accustomed to Blender 2.79, which would allow image texture assignments without using nodes. I know that 2.8 has a new material system that is not backwards compatible with 2.79 files, but I am still curious to know if it is possible to assign image textures in 2.8 without first configuring nodes in the Shader Editor.
Part of my confusion stems from being largely ignorant of node use cases and procedures. I am still learning, but until such time as this is more familiar, I will want to know how image texture assignments can be made in 2.8 without working with nodes. If this is not possible, I will want to know this.
I am especially confused by the option to choose whether to "use nodes" when creating a material. I have found that I can create a cube and assign both a "node using" material color as well as a "non-node using" material color, and one or the other color will display on the same cube depending on whether I've toggled node use on or off. How can more than one material color be assigned to the same object? Why can I have more than one? And why can I even choose NOT to use nodes in the first place if assigning image textures in that case is not possible? Even if possible, the process doesn't seem to be straightforward. The proof is that I could assign image textures in 2.79 without nodes and not fail to successfully do so. In 2.8, I cannot.
If it isn't possible to simply assign image textures to objects anymore without working with nodes, then I expect this will represent a hurdle to many who once were able to do this. If it is still possible to assign image textures the old-fashioned way (even while this is, granted, a very limited approach), then how can I do it?

https://blender.stackexchange.com/questions/139621/blender-2-8-do-materials-always-have-textures/139649#139649

Watch this two videos from Blender official channel: https://youtu.be/0zrd37k2tJM and https://youtu.be/TMPjKVgTfYs

I've been linked to videos specifically about the Shader Editor, or about using the Shader Editor to assign textures, when my question is specifically whether image textures can be assigned in 2.8 without use of the Shader Editor, or if this is not possible. A simple "yes" or "no" would answer my question. These videos do not provide an answer.

I've also been linked to a previous Q&A on this site that explains some very basic (and possibly helpful) things about the relationship between materials and textures. But it still does not help me understand why the image texture assigning workflow in 2.8 is different than 2.79, nor whether the 2.79 image texture assigning workflow is still possible in 2.8.


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How to Get Object's Coordinates to Display as 0,0,0 when Parented, and Update Transform Values as if Parent was at World Space Origin?
When child object transforms are zeroed out, I want the child object to return to the current world space location of its parent, and report 0,0,0 in the child's location transform fields. In addition, applying the location transforms for children should likewise be based off of this same parent world space location, and not the world space origin. This is how parent-child behaviors commonly work in other programs. But seemingly not in Blender.
I've been researching this problem both on and off this site. It appears that other people are asking similar questions, both here and elsewhere, and are not getting answers. Or are getting the wrong answers. Or they are being told that scripting is the key. How could scripting be the key?
I want to zero out child transforms and have the child object end up wherever its parent is currently located. Can this be done in Blender? If it can't be, then what is the workflow I'm expected to adopt so that I won't need children to return to parent locations when their transforms are zeroed out? The only thing i can think of as a workaround is to create everything that needs parenting at the world space origin. That is not always practical.
Why are all location transforms always global coordinates in Blender? Even the use of Delta transforms doesn't make for an intuitive workaround. In some ways, conceptualizing the spatial relationships between parents and children becomes even worse with Deltas. It's also inconvenient to need to go somewhere else in the UI to manage transform values.
In Edit Mode, there is both a Local and Global way of viewing coordinates for selected components. But no corresponding option exists for objects in Object Mode. That is not consistent nor convenient.
I don't expect anyone to read the below linked thread in its entirety, but it highlights a discussion on this very topic. If anyone is so inclined, and partakes, they will discover that, apparently, the devs don't see this as a problem in need of fixing. Also, someone in the thread evidently made an in-house addon to make parenting work in Blender the way it works in every other program, and wanted everyone else to know they made it. But they evidently didn't want anyone else to have it, because they didn't mention whether it was available publicly. https://developer.blender.org/T68190
The Parent Inverse seems to be an extremely cryptic and convoluted concept, in part because its value is always hidden. It's also a reference entirely too dependent on mathematical jargon to be encouraging to artists and non-programmers. But it's also one that is central to this issue. My understanding is that this value is an offset, and is needed to prevent newly parented objects from automatically snapping to parent origins. It keeps child objects wherever they already are in world space after parenting. Okay. But then, why is this value not used to zero out the child's transforms, since the inverse data would actually be useful for this purpose? Why even have the Parent Inverse function if it is not going to be used to provide this kind of functionality?
This is one of the most frustrating things about Blender for anyone who has ever used another 3D software program. This is especially true for riggers/animators, who want to be able to quickly zero out transform values and get children immediately returned to parent positions.
If I am simply failing to understand the right way to do things, I would love to be told, so long as the right way to do things was demonstrated afterwards.

An example of object parenting
Object A has its origin in world space at x=10.0, y=10.0, z=10.0
Object B has its origin in world space at x=2.0, y=2.0, z=2.0
When parenting Object B to Object A, Object B ends up in the coordinate space of Object A.
The new coordinates of Object B in local coordinate space, relative to its parent, are: x=-8.0, y=-8.0, z=-8.0
What Blender displays in the UI
Blender does the exact same thing as described above.
Object B does end up in the coordinate space of Object A.
But the coordinates you see in the UI - in the item panel of the 3D view - are still displaying x=2.0, y=2.0, z=2.0. I guess you expected it to display the coordinates in local space like x=-8.0, y=-8.0, z=-8.0.
What you see in that place of the UI is the "location" tied to the so called "Input Matrix" resp. matrix_basis.
The "Input Matrix" is neither the global matrix nor the local matrix, but a particular matrix for user input. Citing the docs:

Matrix access to location, rotation and scale (including deltas),
before constraints and parenting are applied

https://docs.blender.org/api/current/bpy.types.Object.html#bpy.types.Object.matrix_basis
So it’s kind of an unspoilt matrix that is not "polluted" by constraints or parenting.
You could add a "Limit Location" constraint to Object B, limit its location to 0/0/0, but the input matrix remains on 2/2/2.
The "location" that is actually displayed in the UI is the input matrix without delta transforms.
On the one hand it’s a pretty clean and stable matrix to keep user input separate from other influences.
On the other hand I can understand that you’d like to see and edit the final/actual coordinates in local space after parenting.
Possible Solutions
Here’s a corresponding feature request with some discussion:
https://blender.community/c/rightclickselect/hLdbbc/
In there they’re mentioning an addon that adds direct access to world and local matrix in the object properties:
https://gitlab.com/blender3d/addons/object-location-edit/-/releases#v0.03
And here’s an addon that transforms the matrix values in a way that the values of the input matrix become those of the local matrix:
https://github.com/drewcassidy/blender-apply-parent-inverse
You can see and edit all these matrices without any plugin in the Outliner:

Set the Outliner’s display mode to "Data API"
Object -> "Object B" -> Matrix World / Local Matrix / Input Matrix / Parent Inverse Matrix

Checking out the local matrix you’ll see Object B's coordinates are: x=-8.0, y=-8.0, z=-8.0 indeed.

When I cleared the origin it would send the objects origin to world center regardless of where my cursor or origin was, the way I fixed this was by pressing Ctrl +  A as normal but then setting my transforms to delta, this will reset the numbers to 0, and will snap your child to where you want it relative to the parent after moving it away from its origin point


text:
How do I disconnect two objects
So I have this one torus which I copied to get another torus. I did this by clicking shift+D. But now, Blender treats the tori as if they were one entity. If I select one, the other is automatically selected. I'm assuming this happened because I didn't separate them immediately by clicking P.
How can I disconnect them now?

In edit mode you can try pressing 'L' to select one torus and then separate it by P. You can clarify ur question with a few pictures too

Worked like a charm. Thanks.

The reason they are treated as one entity is because you duplicated (part of / all of) the mesh, in Edit mode. To duplicate the object, do it in Object mode.


text:
Hi The model that I'm working with in blender isnt showing up in when I render my work
I'm making a short walk animation with a robot I modeled myself, but when I try to render out my work it doesn't show up. I have tried the following solutions
1 Camera icon is disabled in the outliner
2  Render layer not showing in the compositor
3   Render layer does not include scene layer or the objects are in a layer that is not renderable.
4 Scene layer not selected
5  Cycles camera visibility disabled in object settings
6  Cycles material disables visibility to the camera
7  Objects are not within the range set by the camera clipping
8  Using the wrong scene
9  Strips present in the VSE, and the sequencer box is enabled in the post process section
10  Cycles: Exposure setting in the film section set to 0
11  Depth of field not set properly making the whole scene blurry
12  Object blocking the camera view
13  An object has been set as the active camera.
14   There are no lights on the scene or they are on a different layer.
    Objects have no faces.
15 The Solidify modifier takes over the object and is disabled in Viewport
16  Duplication type set to 'Group' and no group is selected.
17    Duplication issues (under the Object tab in the properties panel), e.g., duplication type is not 'None', and object has no children, or set to 'Group' and no group is selected.
I have checked all of these options, but none of them are the issue

Please provide the blendfile, if you can. https://blend-exchange.giantcowfilms.com

I doubt there was invented new way to block renderability of an object; in all the cases before it was caused by inproper checking of existing options. If you really think you checked everything share a file using a link posted in the comment above

Without seeing any images, or inspecting a sample file it is difficult to help. Please edit your question again and add either (or both) pieces of information so that it is easier to help you.

Judging by the limited info you have put out in your questions, for blender-render these two remaining things might be the reasons why it's not appearing in your final render.
Draw type set to something other than solid or textured and duplication settings is set to anything other than none

Try setting it to textured and none
Something's wrong in the Render layer settings

Maybe you accidentally turned off the renderlayer or the solid option in the Render settings.


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map 2d coordinates to 1d index using blender drivers

is there a clean way to convert a 2d vector ( from relative position between two objects ) to 1d index using blender drivers? it should be extendable to add more items later . it is useful to control a grease pencil frame with 'Time Offset' fixed modifier.

Pythagorean theorem applied for distance in python: ((op2.x-op1.x)**2+(op2.y-op1.y)**2)**0.5 Does this work for what you need?

round() or int() can convert to indexing number for you

@ZargulTheWizard  that gives distance , distance is 1d . i want a 2d panel , then convert it to 1d

? It converts the 2d to 1d, I had assumed to have the 2d you'd just leave one axis out.

@ZargulTheWizard you'r right but that gives a symmetrical square on diagonal axis.

I don't understand. Are you trying to locate a piece on a board from one number (say, to index the object out of a list of all objects), but to get that number from the object's position?

@ZargulTheWizard i need a grid with unique id for each cell . if i put an object inside a cell , i get the id .

I don't know if there is a solution to grease pencil related but in a shader node you could use a formular like
Index = Row * GridWith + Column
to get an index from a 2d Point.

...I just did this answer again, but more readymade XD

After I thought through it, I realized your answer was same as mine :)

To translate global position into a position in a grid:
Basically, if the grid can have numeric identities in reading order...
This relies on the grid being cartessian, and made of one meter cells. I placed the corner of the top left cell at the origin. Conversion to polar coordinates is probably possible, but more complicated (need to know I'm on the right track first so no wasted work, you know ;-)
#round(pos.x-0.5)+round(-pos.y-0.5)*GRID_X_SIZE


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Subdiving Alembic Crashes Blender
So importing an alembic from Houdini and wanted to throw a subdivide modifier on it and every time it crashes blender. Can confirm the alembic can be subdivided in C4D
Here's a link to the file. Just make sure the alembic is targeting the right directory
https://www.dropbox.com/s/0ljsmdq7wp1mov2/Alembic%20Test.zip?dl=0
Comp specs are fine, also just using a light file for troubleshooting before anything heavy comes into blender ie. fluidsim
2x 2080ti
128gb ram
AMD 2950x 16 core 3.5ghz

Need more information about the object, it is possible the object has become to complex  for your machine with additional modifiers added to it. Please [edit] your question and add images at least.

Usually Blender wil lock-up when crunching alot of information, as long as nothing is pressed during this time you usually get through it after 10-40 seconds, if anything gets pressed it locks permanently and it usually needs to be manually shutdown.

I think it could be in a constant loop as this alembic I was using had nothing to subdiv on the first few frames be fore the type scales up and out. Feel free to test it out with the file in the dropbox link.
As for subdiving other alembics with success, yes blender does take a while to figure out what it needs to do. Guess its not optimized as much as what C4D as it instantly subdiv'd it


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Using the output of the shader as a masking factor in the cycles?

I use the output of the material(shader) as a masking factor in the Blender Internal renderer.
I tried to do the same in Cycles but it didn't work.
Is it possible to use only texture or input nodes as a masking source in Cycles? Or am I making the wrong nodetree?
What I'm worried about is that when Blender Interal is completely replaced by EEVEE and disappears from Blender, the way I use it is useless.
I would like to ask you if there is something I know wrong or if there is another implementation method.
Thank you.
The image below is a close-up capture of the node I made.

It's not quite clear what your ultimate goal is, so it's hard to come up with other ways of doing the same thing. I suspect you'll find some usefulness in the dot product of the geometry normal and the vector to the camera. If the dot product of those two angles is 0, then the normal is pointing perpendicular to the camera. If the dot product is 1, then the normal is pointing directly at the camera. Use a Ramp to blend between 0-1. Maybe something similar with the angle to a lamp instead of the camera. More info would help.

If, on the other hand, what you're actually after is the final color of the surface, you'll likely have to do that in post. The shader doesn't have a way to know the final color in the image.

Okay, my final goal is shell shading.
BI can use the shadow border as a masking factor and can directly specify the color of both sides.
Cycles' Toon shader does not look like that. Guilty Gear Xrd, who is rated the ultimate NPR art style in the current production interview, shows that they uses a separate map to compensate for the color of dark areas for more beauty. BI, on the other hand, is very intuitive because it does not need a map.

Normal Editing is now possible in Blender due to 'User Normal Translator' or 'Blend4Web'. In addition, the intuitive coloring of BI and the fast pace of OpenGL rendering make it a great combination for creating NPR-style footage. When BI disappeared due to EEVEE, I hope EEVEE or Cycles will do the same, but it seems difficult at this time.
tell me your opinions please.


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How to transmit uv and texture when using Tissue

When I create a mesh using a tissue, the material and texture are transferred from the source mesh, but the UV is not transmitted.
I can manually edit the UV because the result in the above image is simple.
However, if the density of the pattern becomes more complicated, UV editing becomes too difficult.
Let me know if you have a way to transmit UVs in the Tissue or easily edit complex UV patterns.
--(new image)

i think before 1st uvwrap on that small part and then make use of the tissue addon

Please explain in more detail.

With the small part of the mesh selected apply scale and rotation and unwrap the image.
Take a mesh that tissue is going to apply (i have taken a cube and subdivide few times)
Select the small mesh and hold shift and click Cube and click on tessellate in tool shelf
Now we got the new shape of the mesh from the Addon with no material and no uv applied to it. Go to edit mode and select all faces and Press Ctrl+N (flip Normal)
In the Edit mode Press L key on one face which select the small part of the mesh.
With the small face selected Press Shift+G -> Area
And now the complete mesh is selected
Press U to unwrap
And apply material on to it.

Thank you. But I used Susan Objects to convey my questions more specifically. (Check the attached new photo in the question.) For objects with curved surfaces, your method is not right. What is the best way to use tissue and tile textures together?


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How to fix the results of a particle system to a specific frame
The image below is about 42 frames from the force field effected Newtonian particle system.
I would like to use the status of these 42 frames as the key for Keyed Particles.
However, I don't know how to keep only specific frames of moving Newtonian particles affected by Force Field.
Thanks.

Not too sure what you're trying to do, but if you want to 'capture' particles at a certain frame, this is easily done but the capture process would convert them all to individual meshes in their own right.  i.e. they'd no longer be particles.  Be aware that their rendering would have to be from a mesh object such as a cube.  Once meshed, they could have physical properties. The method is to select the emitter, go to it's properties at right, open the modifier panel.  Press the "Convert" button and the particles will convert to mesh, albeit a lot of them !

When I converted a particle to a mesh, I could not keep the particle's position completely like the image attached to my question.
Instead, I was able to get a rough position by creating a new volume particle system in the converted mesh.
It is not perfect, but I am satisfied with it and going to next step.

J. SungHoon, that's curious.   I detected no change when I pressed the Convert button and have done it again, still with no detectable change.  Could it be changing somewhat when converting back to a new particle system?   Should I place my suggestion up as an answer to your initial problem?

Yes, there is a difference between the two.
The image attached to the question is that the particles emitted from the box mesh were influenced by the Turbulent force field.
But since it's only 42 frames, I can not use this particle's position as a target for keyed particles.
Because I only want to use the position of the particles captured at 42 frames as a target.

I got an answer from you and tried to convert at 42 frames with the particle render option set to metaball.
Then a new mesh was created with the turbulent force of the existing shape, and a volume particle system of no physics option was created on that mesh to obtain a roughly similar fixed particle location.
I was satisfied because this approximate location was valid for my animation.

And the next day I made a new attempt.
Previously, I used a metaball, but this time instead, I use an object with only one vertex as the particle render target.
This allows you to capture exactly one frame of the particle being animated.


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How do I get images named sequentially when using the 'Frame step' render option?
I skipped frames using the Frame Step Control in the Dimensions panel of the Render tab to output the sequence.
As a result, if you look at the names of the files in the Windows folder, you can see that there are omissions in number increments like img_1, img_3, img_5 ....
I'm currently converting names manually using a separate name batch tool, but this is a cumbersome and repetitive task.
Is there a way to have a sequential number, even if I output a skipped frame using the Frame Step function in Blender?

Thank you for suggesting great methods.
Your method works great on single-pass output.
But there is one thing I have not told you.
I actually want to use multi-pass output using the file output node.
I have found the Time Remapping feature in the dimension panel of the Render tab in other threads, but this causes distortion in the keyframe and interframe spacing.
The way to use the Speed Control Strip in VSE was not distorted, but it could not be used with the file output node. (It seems to be the best way for a single pass.)
The Windows automatic name feature is nice. Thanks Bill Gates, but it is still inconvenient to work with many passes and cuts.
And I'm going to try another batch name tool I did not know about.
I hope I can change the odd number to a sequential number with one click.
But I have not tried it yet.
Is there any other way to get sequential numbering of images output through the Frame Step option and the file output node?

I attached a screenshot at the request of Mutant Bob.
As you can see, I would like to use the file-out node to output multiple passes on one Scene and send it to another composite tool (Natron, Fusion, Nuke, AE,
 Reimport to Blender, etc ...) With the Frame Step option in the Dimensions Panel, fill in the Value Box with two or more numbers. (I'm creating CG for inserting into 12fps 2D animation.)
VSE could not be used with the File Output node because only a single input connected to a Composite node could be loaded into a Strip.

Can you provide a link that describes "multi pass output using the file output node".  I want to figure out if there's a way to make it work in a normal rendering pipeline.

I can think of two techniques:
1) Create a second scene using the VSE to add a Scene strip and then apply a Speed Control modifier to make the scene run double speed.
2) use a shell script to make symlinks like
i=1

S=/var/tmp/blender/knot-hop

D=$S/sequence

mkdir $D

for f in $S/scene1/*.png $S/scene2/*.png $S/scene3/*.png; do
    o=$D/$(printf %04d $i).png
    [ -e $o ] && rm $o
    ln -s $f $o
    i=`expr $i + 1`
done

# make sure we don't have any stale files left over
o=$D/$(printf %04d $i).png
rm -f $o

Wow.  That file node stack you added to the question is pretty tall.

If you are on windows and all images are in the same folder, you can do this:
1. Select the first file

2. Select all by CTRL-A

3. Press F2 and type a new name

4. Call Bill Gates to say "Thank you"
Drawbacks:

It's not fully automated
The postfix is always in brackets like (1), (2) etc.

For the drawback №2 one should really thank Bill Gates. And likely use external file manager


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How to constrain edge slide to axis?
Trying to do a simple edge slide but it keeps twisting at angles when moved.  I am trying to just move them along its connected path whilst keeping the vertical alignment.
Because the top is curved, it is longer and twists? Any help appreciated, thanks.
no photo as file is deleted to start again. but answer still desired.

could you please show a screenshot?

I'm afraid it is still very vague   :/   a screenshot would really help

This is due to the extra edge you have on the top surface.
You can enable clamp (hold Alt or press C) after sliding the edge far away from it, but it's not perfect. Removing the edge works best, if you don't need it:

To get an edge where you've indicated, you might find it easier to use the knife tool, at least in this case:

Line up the view with the orientation you want the edge to be in (and ensure you're in orthographic view, numpad 5)
Start the knife tool with K
Click the top vertex, enable angle constrain (C)
Click the bottom edge:

Note that there are many ways you can go about doing this, for example vertex snapping combined with axis constraints can solve this and many similar puzzles:

Set the snapping type to Vertex
Grab (G) the top vertex and hold Ctrl to snap it to other vertices.
Grab the bottom vertex, constrain to the the X Y plane (ShiftZ), and hold Ctrl while hovering over the top vertex.

Note: I am trying to snap to the vertice you have deleted :)

@dave44 I've updated my answer


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How to model parts of the face of this character?
I'm trying to model this character of mine for animation and rigging:

But every time I try to go about modeling her I always end up getting stuck on either her eyes, nose, or mouth. Those seem the most tricky parts for me.
I've tried spline modeling, sculpting, box modeling, point to point modeling, and even plane modeling. All with different results, but I end up getting stuck when I come across those troublesome areas no matter what.
Edit 1: I've also searched for reference images of rabbits, their topology, anatomy, and looked upon other works from other 3d artists to get an idea of what to do. I still end up stuck.
Edit 2: I changed the question into something a little less broad but will change it more if necessary, just let me know. Still new to how posting questions works on this site.
Here are some screen shots of my progress.

Edit 3: Currently trying to sculpt the head again and will do the rest soon. Someone suggested I do a sculpt first, then retopologize everything and work from there. Which sounds easy enough, but still hard to achieve the shape and style to the reference. Though I know I will get it eventually.
Here are some screenshots:

Your link to the image seems to be broken... Check the permission on your google drive sharing settings.

Hello and welcome. Unfortunately as it stands this question is too broad to be answerable here without modelling the whole character. Could you maybe show us how far you got modeling the head and perhaps show screenshots of what specific issues you were stuck with? It might be easier to help you solve those

Thanks everyone for helping me out here. I will keep my posts more organized in the future :)

I am by no means an expert in organic modelling or character edgeflow but I'd say from what I've seen around it looks like your base mesh is too complex as too many polygons. Try simplifying it a little. See http://topologyguides.com

While character modeling is topic by itself and main rules should be picked from general guides and tutorials, you can take topology example of similar character made before https://www.furaffinity.net/view/19319760/

@MrZak As it turns out, I was following that example beforehand :D, but wasn't sure how to reference the topology and tweak it a little to fit my character, especially at the angle their model is in.

CGCookie has some videos showing good edge loops. Your edge loops need to follow the shape of your character, that includes the shape when it is animated into an extreme pose. You have good loops around the eyes, maybe getting too dense. The cheeks and under the chin you are too square, you need to follow the shape more.


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initial velocity for simulating planetary motion
I was going to simulate planetary motion in blender and i have simulated the gravitational attraction between two planets with rigid body and force field.
but i don't have any idea about how to give one of them initial velocity with physical accuracy
If there is a way to do this with python that would be awesome!!
Here is my blender file :
https://gofile.io/d/XnTyAw

There is a problem with the common trick of giving objects initial velocity because it suddenly disappears :

Related https://blender.stackexchange.com/questions/118441/gravity-simulation

@batFINGER it doesn't work!!! i have added something check it out

an initial velocity in a rigid body simulation is very easy to do:

check animated checkbox and keyframe a location

keyframe another location on another later frame (distance + keyframe distance will "make" the speed

one keyframe later: disable animated checkbox and keyframe it

I've tried this and the object suddenly vanishes

that was your question, and that is my answer. of course - if there are some other circumstances like force fields or parenting (like you have) it behaves differently. One problem in your simulation is: you turned gravity on which is in your case - nonsense - because gravity in Blender is in one direction (normally -z - but you can change that). But in your case you don't want that, because you want "space gravity between objects) and not directional gravity(simplified) like on earth.

It disappears because of gravity in -z direction!!

so how to fix?(sorry i'm beginner)


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Help me to fix reflection problem

My helmet reflection is distorted when I move a bone head. I don't know how to solve is
https://drive.google.com/file/d/1n41ku7dmLktpH3lJzI8Bnjf__MsHi-nB/view?usp=sharing

hello, it is not clear, do you mean that the object is deformed? Please share your file: https://pasteall.org/blend/

sorry, i added link to description

when i open your file the helmet isn't even on the shoulders...just laying around. So maybe you should upload a version which looks like your screenshot....

Your mesh is high-poly, which will make rigging and animations more complicated imho, but what you could do is join the helmet to the rest of the body (CtrlJ), remove its vertices from all groups and assign them to the vertex group called spine.006 which is controlled by the head bone:

thanks you very much


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blurry textures on obj
When exporting my object to obj, the pixel texture becomes blurry, in blender itself I fixed it by going to the nodes where the texture is attached to the object as Color, and switched from Linear to Closest, but this doesn't seem to work outside of Blender, thus in the obj file format.
Is there some way that it could recognize such configuration? Or another type of file perhaps?

I know Closest will be exported with glTF.

seems like this file format won't work for me, I'm exporting into a game engine