text:
Is a good edge flow essential for uv-mapping and texturing?
i'm busy trying to make a guitar in Blender and I wondered if it's necessary to have a better edge flow in the head of the guitar when I am going to UV-unwrap the mesh. I have no shading problems and there are no Ngons or triangles present in the mesh. But when I create an edge in the head of the guitar the flow of the edge is really bad as you can see here:

This problem started when I created the holesin the head with the boolean modifier. Is this going to create a problem for me in the future. Should I try to clean up the mesh till I get a good edge flow?
Thx for your help!

Cleaning up a mesh is always a good idea as it promotes good practice of edge flow. However I can see that you have some sort of weird faceting going on (marked in red) and I've drawn, in blue how you'd go about fixing that. You need edges in there or you'll get that weird thing going on. Can you maybe disable the subdivision so I can get a better look at the topology? As it stands triangles and n-gons don't really affect the UV map if you unwrap it correctly but, as I said, understanding good topology will serve you  well in the future.
https://gyazo.com/413fb2b6dc1cbc79853c4c80128f4900

I have added another picture without subdivision. I should really learn how to clean up meshes especially after using the bool tool.

With circular shapes you typically want to keep the topology flowing like this:
https://gyazo.com/56d5bfde069d002cc571a1b0b3e35cd3
It just keeps things neater and such and presents good edge flow. To answer your question about UVW unwrapping you can add a colour UV grid to see how the UV's will affect a texture. Then apply said texture to your model. Unless you already knew that lol
https://gyazo.com/34b6b4b3826c4ef70e2e67075929fcff

Ah yeah I knew, but thanks for the tip anyway haha. Thanks for your help! I will try to make the topology more like you suggested. :)

A good rule of thumb is "if it looks awkward then it probably is." Just keep at it and you'll develop a sort of gut instinct for that sort of thing ^.^

Damnit time to remake the whole guitar then :)

No don't say that! Just use the knowledge you now have for the next project! You'll never learn anything if you keep starting again lol.


text:
Fluid Bake Not staying
I baked some fluid stuff and it was great. But when I saved the file and uploaded it to my online drive, the fluid bake didn't show up and I had to re-bake it again.
How do I keep the bake so that I can upload the file and still have it once I re-download it?

While i do not know exactly which version you used to bake, it would only make a slight difference. The main problem is, that the .blend file you save/upload does not contain the baked cache used for the animation.

As you can see in the picture above, there is a cache folder where the data needed is stored. That folder contains what you baked and needs to be uploaded as well.
Depending on the size/resolution of the simulation it can fast become really big though.
While the .blend file saves where you stored the cache, you can always just click on the folder icon and search the folder in case you renamed it for uploading or packed and unpacked it somewhere.
Solution: Save the .blend file and pack it together with the "Cache-Folder" to upload it together. Later you can unpack it and only need to select the right folder when opening the .blend file to skip baking anew.

Thanks so much!

source: Stack Exchange

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

sort: votes


text:
Why are the flat paper objects in my scene disappearing in and out again?
Help! I made a corkboard type of scene and the papers are cutting in and out for some reason. And no, It has nothing to do with the clip start and end settings, or the papers being too close to the board. I moved them a TON and nothing changed.

Here is a video of the problem

Are the papers absolutely flat against the wall? What I mean is, are they in the exact same spot as the wall? If the papers and the wall behind them occupy the same space, the camera cannot decide what's supposed to be "in front" at any given time and will waver between which it displays (possibly based on camera angle). If this is the case, move the papers "forward" even as much as .0001 of a unit.

please upload your blend file, if Christopher's answer doesn't help you.

so this was the first thing I thought of, christopher. I moved them around and they are not very close to the wall. its so wierd. I'll upload the file.

heres the file: https://drive.google.com/file/d/1PPUi2SBUv3zbEhSTrG2hy9E_KzvdA6iT/view?usp=sharing

The problem is only visible in eevee render viewport mode.

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

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


text:
Multiple buttons assigned to the same Operator class
Does every new button need to be assigned to a different operator class or can you assign multiple buttons to the same class to do different things.  Here is the code.  This panel is located in the Video Sequence editor.
import bpy

class CustomPanel(bpy.types.Panel):
    bl_label = "Left, Right Button Test"
    bl_space_type = "SEQUENCE_EDITOR"
    bl_region_type = "UI"
    bl_options = {'DEFAULT_CLOSED'}

    def draw(self, context):

        def add_center_button():
            row = self.layout.row(align=True)
            row.operator("sequencer.center_images", text="Center A")
            row.operator("sequencer.center_images", text="Center B")

        add_center_button()

class Center_Images(bpy.types.Operator):
    bl_idname = "sequencer.center_images"
    bl_label = "Center"

    def execute(self, context):
        print("Center button is being executed")

        return {'FINISHED'}

def register():
    bpy.utils.register_module(__name__)

def unregister():
    bpy.utils.unregister_module(__name__)

if __name__ == "__main__":
    register()

Have a look at the usage of the operator's "number" property here: http://blender.stackexchange.com/questions/75814/how-to-make-this-script-to-quickly-set-specific-weights-screenshot-attached/75851#75851

That cleared things up along with how bpy.props.Properties works in one fell swoop!

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


text:
search for unknown operator 'BPY_OT_OPS_OT_mesh.dissolve_limited()
The menu for this code is in the the video sequencer.  It just brings in an image file into the video sequencer.  It works except that I get search for unknown operator 'BPY_OT_OPS_OT_mesh.dissolve_limited()'.  It gives that error 3 times in a row.  I'm not dealing with meshes at all in the code but Dissolve Limited is something that I just started using recently.  So I tested it on an older version of Blender I have and the error didn't show.  I don't know if I saved a default state after I started using it or its something behind the scenes that is beyond me.  I think the solution is to erase whatever traces in memory it resides in or something.  Anyway to remove this error?
import bpy
import os
import operator

class CustomPanel(bpy.types.Panel):
    bl_label = "OpenSource::Classicism XL"
    bl_space_type = "SEQUENCE_EDITOR"
    bl_region_type = "UI"
    bl_options = {'DEFAULT_CLOSED'}

    def draw(self, context):
        def add_label():
        row = self.layout.row()
        row.label("Intro Directory")

    def add_import_button():
        col = self.layout.split().column(align = True)
        col.operator("sequencer.add_intro" , text= "Import")

    add_label()
    add_import_button()

class Add_Intro(bpy.types.Operator):
    bl_idname = "sequencer.add_intro"
    bl_label = "Add Intro"

    def execute(self, context):

        def add_splash_screen():
            bpy.ops.sequencer.image_strip_add(directory="C:\\Users\\....png", "name":"image_file.png"}], frame_start=1, frame_end=26, channel=1)

        add_splash_screen()

    return {'FINISHED'}

def register():
    bpy.utils.register_module(__name__)

def unregister():
    bpy.utils.unregister_module(__name__)

if __name__ == "__main__":
    register()

I tried your script and had a few other issues aside from the one you mentioned. I tweaked it to make it work and had no issues. I bet you're getting the search for unknown operator from something else. Try going to File > Load Factory Settings to reset Blender.
import bpy
import os
import operator

class CustomPanel(bpy.types.Panel):
    bl_label = "OpenSource::Classicism XL"
    bl_space_type = "SEQUENCE_EDITOR"
    bl_region_type = "UI"
    bl_options = {'DEFAULT_CLOSED'}

    def draw(self, context):
        row = self.layout.row()
        row.label("Intro Directory")

        col = self.layout.split().column(align = True)
        col.operator("sequencer.add_intro" , text= "Import")

class Add_Intro(bpy.types.Operator):
    bl_idname = "sequencer.add_intro"
    bl_label = "Add Intro"

    def execute(self, context):

        def add_splash_screen():
            bpy.ops.sequencer.image_strip_add(directory="/home/doakey/Desktop/image.png", files=[{"name":"image.png"}], frame_start=1, frame_end=26, channel=1)

        add_splash_screen()

        return {'FINISHED'}

def register():
    bpy.utils.register_module(__name__)

def unregister():
    bpy.utils.unregister_module(__name__)

if __name__ == "__main__":
    register()

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


text:
Making a material fade off(progressive transparency from front to back) based on the location of its geometry
I'd like to make this object half transparent, on one side and half atmosphere-looking in the front.
Here is what I'd like to look like :

Here is what I currently have :

Also note that the geometry is like this :

The inner part of the object is the light emissive part, and the outer region is for the atmosphere, I gave them both different materials, I want the effect I am talking about on the outer material.
Thanks for any help!

In this video tutorial https://www.youtube.com/watch?v=cPvYAHc9vCE I use an empty to control where the texture is affecting the transparency.

You can try something like this:
This is the same set up from your previous Question what was added was a gradient texture node added to the beginning of the chain of nodes. I put the color ramp node so you can control where the falloff to transparency ends.

I tried a render with this precise settings at first I thought it was okay, it was exactly what I wanted but now we don't know where the front of the bullet is in relation to where the back of it is.I think I find it out after messing around a bit with the geometry and the material, it was simple actually. Also, I'm sorry I misexplained what I actually wanted.I'll probably answer my question someday, thanks for the help.


text:
How to make this particular blender material in Cycles
I've seen this material which has been made using blender rendering's engine, and I'd like to give it a fresh look in Cycles.
Here is a screenshot of the nodes and the previewed material :

However, I tried using Layer Weights but the layers(white then blue) were not correctly applied to the subdivided Icosphere.
Plus in Cycles, I don't know how to use the alpha output since there is none on the material output node when using Cycle rendering engine.
I am a bit of newbie towards this, usually, I try things on the node editor, and they work out fine but this time, I really don't know what to do.
So if someone could explain to me, how to make this particular material using Cycle(even like if it's a bit more realistic), I'll be glad to take it as well as an explanation of the process during the making of it.
Thanks for any help!

Instead of thinking of "alpha" you should look fot the Transparent shader. Could you please show your result with the subdivided icosphere in order to exactly understand why you are not satified with the result?

If you want to do that in cycles the set up would look like this:
The layer weight node controls the falloff for blue and white respectively in combination with the color ramp to clamp the falloff.
Of course the transparent node is to cutout the center, you might also want to play with the roughness on the glossy shaders, it will give you a different look .

Can we make the whole material appears more brighter it feels like it's fading off, I guess the transparency is affecting the borders too much, can't we control it more precisely for the center only?

You can't control the center so you have to mess around with the layer weight and color ramp nodes. The layer weight will control the "fading off" part and the color ramp will control how thick the white and blue parts are.

Also the roughness in the glossy nodes can help with the "fading off" part

Okay, thanks, I'm messing with it right now, but I can't seem to get the proper result, I've added an Emission shader also to get it to be brighter but there are black borders between the white and blue.

By Replacing the glossy shaders with Emission shaders, I got a better result, thanks the setup.


text:
How to add a curve into this ōdachi?
I am wondering if there is any way to add a curve to this ōdachi I made without having to go into the mesh and add it manually, since it'll be very painstakingly difficult to do it manually.
Thank you in advance!

It has been updated

Sadly none of these helped since the mesh of the sword was pretty broken, so I ended up manually making the blade part over again and then weight painted it to curve. Thank you for the suggestions though!


text:
Alpha over compositor problem
I'm trying to add a fog glow to the blue circles behind Susan using the compositor but so far not being able to make it, the fog glow is applied to all the image but no the blue circles or sometimes the blue circles appear on top of Susan lol
Thanks guys for your help, I'm new to the compositing world of Blender.
Blender file attached*

You should separate your image like this:
Monkey only - renderlayer #1 (foreground);
Circles only - renderlayer #2 (middleground);
Purple backing only - renderlayer #3 (background).
Don't forget to enable transparent background in render tab.
For composing - plug circles to the Glow node and then use Alpha Over node to put monkey on top. Now put all of this on top of purple background with second Alpha Over

Hi Serge, thanks for your help, I enabled transparent background, setup the render layers the way you told me, plugged the circles to the Fog glow node, used the alpha over to put monkey on top and used an alpha over to put everything on top of the purple background but so far you can see the result in the new image that I re-uploaded here. I re-uploaded the Blend file with the new node setup that your advice, obviously I'm doing something wrong. thanks for your help    :)

Your mistake that you have a layer ("Main") which combines all in one: monkey, circles and background. In my first post I suggested you to put each of those to their individual layer.

Thanks Serge!! with your help I was able to make it! people like you make Blender the choice to go, what an awesome community.

Papasmurf7777, I'm glad you've worked it out!

Hey Serge, write your comment as answer! I vote it up :)

Either separate by render layers or use a separate RGB in the compositor to create a mask that only select the blue.


text:
Export Null/Empty position/rotation/scale data to After Effects
Is there a way to export a null's position/rot/scale data from an animation and use it later for comping in After Effects?
Thanks

What is "null position data" and what is "AE", could you clarify?

Thought of that too, but wanted to be sure. No idea about the other though, maybe some camera tracking data perhaps?

@DuarteFarrajotaRamos It is After Effects, obviously.
Null position data would be exactly what it looks like, though. Not sure how to describe it properly.
Ex. In Cinema 4D you can export a null's position/rot/scale data from an animation, and use it later for comping in AE.
Thx for the comments, btw

@cegaton Thanks a bunch!
Will check it out.


text:
Creating Live, Editable (Audio Waveform) Oscilloscope in Blender
I've been searching the internet for hours to find the solution to my predicament, but to no avail.
I am trying to create a virtual oscilloscope within blender, which is editable in ways similar to that of a real oscilloscope. All I really need is one (horizontal) channel that can display an audio waveform (music) with a high amount of resolution. What would also be nice (but possibly more complicated) is the ability to manually adjust the window of time that the waveform remains visible before updating, so that a signal of constant frequency remains "in phase" on the display and does not wander around.
Also, as on a real oscilloscope, I anticipate problems with "strobing," whereby the frame rate at which the oscilloscope display updates itself is not in sync with the frame rate of the blender scene. Maybe, if the oscilloscope display updates itself faster, Blender's "shutter" will have to be open long enough to capture multiple iterations of the waveform for that period of time and "ghost" them on top of one another.
Up to this point, I've been trying to increase the frame rate of blender and tweak the properties of the "bake sound to f-curves" option, but the resolution is still not satisfactorily high enough. Yes, it is possible to stretch the waveform in another program (like Audacity) and reimport (re-bake) it, but I want to avoid this as much as possible. My hope is that I can make a virtual oscilloscope display within blender to render music in real time, so that I can add a track in the VSE to hear what's happening and follow along.
Not knowing where the solution lies, I'm open to scripting, although my knowledge of Blender Python is limited, but I'll try best to follow if it ends up going in that direction. (There's plenty to learn there, so it would be a good experience for me anyway).
I've also considered creating a line of particles or vertices, whereby each would be displaced up and down on a designated axis, and which would update themselves each frame (or every subframe, according to the oscilloscope settings).
Thanks all for the help and guidance. I'm suspecting there are multiple solutions, and I'm interested in hearing whatever you all come up with!

Real time and blender often don't mix, but, I'm still interested in seeing a cool solution.

I was recently thinking about if it'd be possible to write a script that'd generate geometry or a texture from audio for such purpose.
I guess the closest thing right now would be to render the waveform with somehing like gplot, and use this as an image texture. My animating the texture mapping offset one should be able to get an oscilloscope-like animation. But it's by no means realtime or easy to pull off.


text:
Mirrored bones and IKs, ends up doing opposite rotations for no reason
When I mirror my bones, IKs, etc.. (even when reseting rotation beforehand) they end-up rotating oppositely (cf. gif).
(https://gfycat.com/equalmaleamericancrocodile)
And nowhere can I find anything to fix it, it's driving me crazy! Even more so when I feel like it's simple and I can't seem to find the way.. Please help me if you can, and thank you in advance to anyone able to give me any insight :)

Object>Apply>All transforms to deltas. Check that first. Then check you are mirroring accordingly in EDIT mode of the armature (check the wrench icon property tab to the left of the screen) and/or the tool's settings on the top bar in the viewport. Mark the correct axis.

Hey, thanks for answering. I did what you said (i think so anyway) but it doesn't seem to change anything.. You said "mark the correct axis" but there's only one axis that I can choose from. So I checked it but maybe it's not the right one? and for some reason I can't see any other?


text:
How to Texture map a model that has a large number of vertices or faces
I have a obj model that I imported into blender. The model is a render of a city so its fairly large. As can be seen from the stats in screenshot below (this is after decimating with a ratio of 0.5)

I also have the texture file for it in png format and I want to map this texture onto the model in blender.
Below is the image I want mapped on the model:

Ive watched a number of tutorials on how to do this and all direct towards changing the material from base color to texture image and then using UV editing to wrap or unwrap the texture onto the model, but the tutorials show cubes and simple objects and when a face of the model is clicked the region of texture is shown that its taken from. But thats not happening in my case, maybe due to the large number of vertices?
See below the screenshot, on the right the model is zoomed in to show what I mean and nothing is being mapped (other than a solid green color)

How do I get the texture mapped onto the model?
Thanks
Update:
Adding the attempts screenshot based on suggestions in answer:
UV Mapping

World Coordinates

edit
Updated model:

In order to solve this problem we have two ways. Which one to choose depends on the type of geometry we are working with, as well as the goals.
UV Mapping
Judging by the grid shown in the last screenshot you can just Unwrap the model:

Select all by pressing A in Edit Mode
U > Unwrap, (in case of complex geometry you can press 7, U > Project from View
Use simple texture mappig set in Shader Editor to make texture follow the UV.

Use World Coordinates
If the mesh contains so many vertices that blender freezes when you try to unwrap the model - solve this with projecting the texture using Position from Geometry Node as Vector for Image Texture Node. Also you can use mapping node to edit the position of the texture relative to object.
For this solution, you don't need UV.

Thanks for the answer Yuri and yes please I will appreciate he edit as Im very new to blender and dont know where to find the options you just mentioned. Thanks

Many thanks for the detailed answer Yuri, but I tried your suggestions and my model and image is not behaving the same way as you have shown in your screenshots. What may the reason be? Ive uploaded the new screenshots to my original question

Can you attach the file, or if it's too big - append the link to some cloud service, please. Don't forget to include textures, you can do it by File > External Data > Automatically Pack into .blend

Ive uploaded the models and texture and added the link to question. Thanks a lot for looking into this :)

I corrected the file according to the instructions I described above. Check it out here. In order for the map texture to be displayed correctly in world coordinates set you need to configure the mapping node. For Uv mapping > Project from view check out this video to clarify the point.

Thank you so much for that. The video helped with the explanation and I got the material on finally :) In your attached blend file the model looks nicer somehow. Mine looks rough (image attached above), while the one in your project looks nicer.. how can I get this look as well please? Also in my project I cannot rotate the camera otherwise the model disappears, but in your blender project I can freely rotate the camera to view model. Please advise how you fixed that as well. And thank you again for your help Yuri :)

Update: Right, I figured out that the reason my model would disappear when rotating is because I had to set the clipping value to some very high value. Setting it to 3000m fixed it. I also got the same look as your model, by reducing the z-scale to 0.3. Im happy that I got the same looking model as your project :) but how come the scale in your model is at 1 whereas I had to reduce it to 0.3 to get the same look? Thanks again :)

@StuckInPhDNoMore Not a problem =). You've got that blinking atrifacts because of small camera cliping for such an huge object. To fix that you can increase cliping amount or just scale down your object to fit in camera clipping. What about scale factor, I just applied it after changing by pressing Ctrl+A > Scale, so it changed back to regular 1. For nicer look you need to go a bit deeper in Shader Editor and how Roughness, Specular and Basic Color works together in Principled BSDF node. To get the same result you can just set Roughness to 1 and Specular to 0.

Thank you <3 :)


text:
Solidify problem with borders 2.79
I take a circle, extrude it, and solidify and obtain a kind of cylinder.
If I deform the cylinder, the border becomes skewed.
How can I have a flat border as if the cylinder was cut with a knife?

You can solve this easily in Blender 2.82+.
In the Solidify Modifier

Set Mode to Complex.
Set Boundary to Flat.

Cool, but im stil with 2,79 :(

well thank yo very much for your answer and your time :-)

because i have to upgrade the macos first, i have to make backup then, change software.. well you know


text:
Blender zooms in when rendering
I know there are lots of questions about this, but I've tried all the given solutions and I'm still having the same issue. When I look at the marked area in the preview window, it shows the whole image, yet when I render, it crops the window to only show about 50% of the whole image for a couple of my video clips- but not all of them. I did some cropping and scaling of all my images, yet their appearance in the preview is how I'd like them to render.
I've checked that the resolution is the same for the image and the render (1280x720) and I've checked that the scale is 100%. Any ideas? Thanks so much!
p.s. The answer might be obvious- this is my first time using blender as a video editor, so thanks in advance for your patience!
Here's a link to my blender file:

Having trouble where you mean to upload my .blend file. Is it possible to do it through this thread? (Sorry this is my first time using blender and posting here)


text:
Clean Up Imported Geometry
If importing Geometry (FBX) to Blender it will import triangulated, which doesn't work with Displacement / Subsurface Modifier. Is there any quick way to clean up imported Geometry without redrawing it? Clean Up from Mesh Menu doesn't work. Remesh Modifier also doesn't work. Second Image shows what happens using Limited Dissolve.

You can try the answer here: https://blender.stackexchange.com/questions/5538/how-do-i-convert-a-triangle-mesh-to-a-quads-one

It depends on mesh complexity but generally there isn't any "quick" way to convert triangulated geometry into quads. Automatic operations so far can convert only some areas and will fail at others. If all you have is fbx then you're out of luck mostly - make a retopology of shapes if it's anything more complex than shown above. It could be more efficient to find out why export into fbx was triangulated

unfortunately it's far more complex. the images only show a quick easy example. so, in conclusion it's not possible to use blender in archviz?

https://blender.stackexchange.com/questions/48954/merge-around-a-face

Use Tris to quads.

It isn't impossible to use Blender for archviz per se which can be seen from multiple visualizations you can find on blenderartists and artstation, however it really depends on pipeline. If it assumes usage of objects from CAD applications with geometry optimization then it could be more efficient to use CAD apps instead (and likely never optimize any geometry). Blender isn't CAD app although it has addons simplifying certain tasks like NP-Station, Archipack, Archimesh etc

No, there is no quick and easy way to fix imported CAD models that have messy and triangulated geometry.
You can try to make it better, but in most cases geometry made in CAD applications is messy to start with and triangulated on top of that. Even though you can see some suggested solutions working on really basic geometry, most of the time models you really need tend to differ a lot from a triangulated cube. Messy geometry typically coming from CAD or solid modelling software packages is usually a lot more difficult to work with when you need to make bevels on it, select and edit parts of it, mark seems, or UV unwrap the models since you cannot use any of the modeling or selection tools related to geometry loops or rings and the topology density is unevenly distributed. It is very easy to get lost in it while trying to fix it and spend way more time working on it than you would if you chose to remodel it from scratch and to end up not only with more time wasted but with a lot lower quality result as well. It is really worth considering to just use this kind of geometry as reference for remodelling it all.
In addition to that, you might come across some automatic retopology solutions out there like for example zRemesher in ZBrush or Quad Remesher and while these seem to be and in a lot of ways are really amazing and miraculous tools, and can indeed be a great help and save many hours of work, they are still unable to solve a lot of cases, so remodeling by hand unfortunately is still very often the only solution.

Cleaning Imported Mesh

in Edit mode Select all A
Merge Alt+M > by Distance
Delete X > Limited Disolve

(or if you want to avoid N-gons use Triangles to Quads Alt+J instead of Limited Disolve)

Hole in Face
Blender can't handle a hole in a single face. Hole can be handled by minimum two faces. For SubSurf you would need face per each edge of hole to generate even curvature. For more search - Subdivion Surface Modeling (topology).
Simple

Catmull-Clark

Smooth
Question also is, if you need SubSurf. Some smoothing can be done by shading type Smooth with enabled Auto Smooth in Object Properties > Normals.
What is the role of Auto-smooth?

breaks the geometry instead of solving the problem

it works if used on a closed face without openings, if there a window opening the geometry breaks. can add a screen shot soon

issue from your second image is not problem of a hole (window) in a wall, but combination of N-gon with SubSurf. If N-gon does not work for some reason use Tris to Quads, but also after that some areas will probably manual retopo need ...


text:
Extruding along an area
I'd like to extrude a profile along the edge of an area. Furthermore, this profile should always stay in contact with the edges adjacent area.
Imagine a ribbon that twists. The resulting area(s) are where my profile should extrude along with.
Profile (orange)

Extrusion path (orange)

Edge of Profile (white) which is in permanent contact with the paths adjacent areas

End of profile (orange)

Thx in advance for every info on how to solve this problem.

You can recreate it using a Bezier curve.

Add a Bezier curve, and use the Tilt Tool to adjust the tilt.
Create the profile shape (It needs to be a curve too). The origin point position is important.
Set the profile shape as a Bevel for your curve. It will align based on it's origin point.

Add a Bezier Curve and tilt the control points. Add more control points if needed.

Create the profile shape and set it as a Bevel object. If it's a mesh object, you'll have to convert it first.

Wow thx so much. Can finally continue my work. :)

Happy to help :). If you get lost somewhere, feel free to ask. Good luck.


text:
Camera Perspective in Layout mode broken - Blender 2.81
I am following the trusty old donut tutorial by Blender Guru, and I have run into an issue.
I am up to part 6, first render. The camera perspective in layout mode does not represent the render output. When I view the camera perspective in any other modes, e.g. Sculpting, the render does in fact represent the camera perspective.
What have I tried?
1. Restarting Blender
2. Load Factory Settings
3. Deleted the camera and created a new one
When I alter the camera angle, the camera angle changes in the layout mode (and all other modes), but the camera perspective in the layout mode is still different to the render output.
What is going on within layout? I am so confused.

Try 0 on the numpad to switch into the camera view (in layout and all other workspaces) or View > Cameras > Active Camera in header menu of the 3d viewport.

@brockmann That's just basic navigation isn't it? I've tried that. I've also tried selecting the camera and pressing CTRL+0 to assign it as the active camera.

That looks more like you've zoomed in /panned into the camera view. Have you tried scrolling or Shift+MMB?

You appear zoomed-in. Even though you have selected the camera view, it will retain the last zoom selected. Each workspace will retain it's own zoom levels. Just zoom out and hopefully that will resolve it. Oh and turn off Lock Camera To View as this sometimes confuses things. Once re-orientated, you can turn it back on.

Good idea @Derrick

Thanks. Zoom was the issue. I expected zoom in and out (scrolling) would affect the camera position. However, when you think about it, the focal length is 50mm (it is a fixed focal length, not varying; e.g. 50-100mm). So zooming just zooms the view port, not the camera focal length. I should have pressed "G" to reposition the camera.


text:
Store Named Attribute Value is turned to zero?
I´m trying to get to attributes from two different points to another mesh. If I´m doing this the attributes (which aren´t zero) are turned to zero. How can I use this value for another node tree?

Please present your problem in a way as clear as possible. Instead of storing multiple attributes, use just one, and spend saved space to present the entire node tree. You wouldn't want an answer to your problem to be so laconic as your question, and with redacted node tree.

The values in the first picture are moving and scaling the selected object. The attributes from the third picture are there, because I want to stretch the object between two points. My problem is that when I try do subtract the x position from the other or use even only one attribute, it is like not there (visible in picture two, the top is only one line instead of a face). @MarkusvonBroady

i think you didn't understand that you cannot use named attribute on two different trees without using sample index node. Every tree/branch has its own named attributes. But i agree to Markus, you didn't even show us your whole node tree - so we can only guess what you did.

I now added the whole node tree but how do I exactly do this with sample index? @Chris


text:
How to create a complex shape for 3d printing with holes using a single mesh
Hello I'm new to Blender, but I'm learning fast. I'm attempting to recreate this for 3D printing:

It's a present for Christmas.
I followed this youtube video tutorial: Turn Any 2D Image to 3D Model - Quick & Easy. I added a plane and applied an image as a texture to get the initial shape.
Now I have a pretty good starting mesh:

I'm trying to remove the spaces that have been marked with edges to extrude the shape I'm going for. I've tried the solutions in this question: Boolean within the same object?. I've tried a Geometry Node using Mesh Boolean and creating duplicate sub-objects and using the boolean modifier to subtract the space. The former ends with odd results and the latter doesn't work at all.
Here is the result of using the Mesh Boolean Geometry Node:
Can anyone offer guidance on removing the 4 spaces seen in the first image?

pls provide blend file, thx

Use Delete > Limited Disolve. Convert Mesh to Curve, under curve properties switch curve from 3D to 2D, Fill Mode > Both, than you can set Geometry > Extrude, Bevel (use Depth value in Offset, but in negative value) ... when you are fine with result convert to Mesh.

Use Delete > Limited Disolve. You dont need so many points.

Convert Mesh to Curve, under curve properties switch curve from 3D to 2D, Fill Mode > Both ...

than you can set Geometry > Extrude, Bevel (use Depth value in Offset, but in negative value) ...

when you are fine with result convert to Mesh.

BTW ... note to your tutorial you follow ... there is much straight forward way :) Just drag&drop your black&white image into 3Dviewport and search for Trace Image to Grease Pencil ... than search Convert Grease Pencil > Bezier Curve (don't use Convert to operator that is not mean to be be for GP, this still confuse me). Now just set mentioned curve properties.


text:
After opening a new project, the screen shows black and only outlines with no textures nor gridlines. Is there a setting that i need to change?
Is there any way i can show the screen?
After opening a new project, the screen shows nothing but outlines, even with newly added objects. This is a freshly installed Blender without any setting changes since i'm just starting to learn blender. I use a Windows 8.1 and Blender 4.0.
Blender 4.0.2
CPU : Intel(R) Pentium(R) CPU G3240 @3.10Ghz
RAM : 8 GB DDR3
GPU : AMD Radeon R7 200 Series
GPU Driver version : 13.251.9001.1001
Blender from Blender.org
[1]: https://i.sstatic.net/znK5h.jpg

Check that your GPU and driver is supported by Blender 4. This is the section about AMD cards in the Blender docs.

Hello and welcome. Instead of having users go through links and external sites please use the builtin tools to embed images in your post. See How to upload an image to a post? or GIF


text:
Gravity on Instances
I am trying to add gravity to instances and it went pretty well until I realized it looked like it was glued to it's base surface, so I made a normal particle system to compare and it definetely feels glued to the surface, is it any possible to get the same result in geometry nodes ?
3D View

Nodes

And here's the file:

The node screen capture is very small, can you upload a better image or share your file?

@lemon sorry about that, I edited the file into the post.

The problem with your setup is, you have animated location, rotation and scale of the base object that holds the Geometry Nodes modifier. You can think of it as being the parent object to everything generated by the GN nodetree.
Other than the regular particle system in Blender, the points are like the mesh of the GN object. They change their position within the object (like for example vertices moved with a shape key), but they are bound to the translations of the object they belong to.
Now you can do one of two things:

Delete the keyframes for the GN object. Use a separate external object and animate its movement. Bring it into the GN nodetree with an Object Info node (set to Relative) and distribute the points on it.

The second method would be:

Delete the keyframes for the GN object. Add a Transform Geometry node between the Grid node and the Distribute Points on Faces node. Animate the transform values. But beware, you have scaled the GN object to 0.225 without applying the scale. This means when you set the Transform Geometry node to move the grid 1 m on X, it will only be moved 0.225 m.

The first solution did it for me, tysm for the help !

They appear to be glued because you are generating new ones at each step of the simulation:

Instead you should do something like this:

This is not related to the question, but quite similar setting at the output:

As the instances are deleted after the simulation zone, they're still part of the simulation. This is not visible as they are deleted, though, they still weight the simulation part.
You should instead do something like this:

This is not the point of the question, see my answer. The point is the emitted particles move with the emitter instead of keep falling where they were emitted.

@GordonBrinkmann, ok, maybe...


text:
Move Multiple Keyframes using a value
I've made a geometry nodes asset which consist of multiple planes scattered around a point, I then applied a material to it which is a simple emissive gradient spherical texture. At frame 0, the emission strength is at 10 while at frame 10, it is at a strength of 0. This asset is kinda like fireworks in a way, as in I need a lot of them with each having different colors or emission strength values at different frames. As of now if I wanted to have another asset within a different frame, id need a different texture every time I want to do that. Which is  why I am wondering, is it possible to move keyframes, like how you move them with your mouse but with a value instead ?

Shader editor and the Timeline

Value I want to use to move said keyframes

Please share all the relevant information including the node setup you are using. Moving keyframes is not how things like this are done. You should aim to atchieve your goals other way. You have access to scene time from geometry nodes so you can animate with geometry nodes. In order to advice people will still need to know your precise situation. This is no different than your previous question you deleted. You should provide the full context if you want to get help, because without it it's not possible.

Did you mean to say "mouse" instead of "mouth" in your question?  Please edit.

@Martynas Žiemys Again I apologize for the inconvenience, my question has been answered but I'Il make sure to give as much details as needed for my next question.

@james_t oops that is my bad lol, I corrected it.

Here is a solution that uses an animated custom property on the object that I named "EmissionValue" and where for each copy of the object I adjusted the value inserted keyframes at the desired frame number.

I include my blender example:

Thank you so much, exactly what I was looking for!


text:
Subdivide a face into 1 x 1 squares
I have a mesh (just 1 face) that was created in another program that tries to optimise the mesh when exporting.  I would like to subdivide it 1 x 1 square grid like pattern (which is basically how the program created it in the first place).
I tried subdivide, but that just adds more vertices to the edges.
Is there an easy / quick method instead of me cutting it up manually with the knife tool, as I will likely have more meshes like this to clean up and work with?

File added (different mesh):

You could try the Remesh modifier.

Can you upload your file? There could be a way; i want to prove directly on your mesh

You can also try Grid Fill. Tab into Edit Mode, key A once or twice until everything is selected, key X to open the Delete menu, and select Only Faces. Key Space to open the search menu, type Grid Fill, then key Enter.

Of course the subdivision didn't work. It only works on Tris and Quads.

@RichSedman I tried that, but the mesh vanished, I played with the settings but couldn't get it to show.

@Fuboski Unfortunately I have a lot in the blend file that I can't make public.  I can reproduce it with a plane subdivided a few times, then a few faces deleted.

@ShadyPuck I thought that would work as well, but it doesn't.  It does cut it up, but it's not as I want.  I tried playing with the span, but couldn't get it how I want.

@Hendriks3D Ok.  Sorry that I am still a beginner.

Can't you duplicate this file (the plane in the image you posted) on another file blend? Just a copy of the single mesh

Must admit that I haven't tried Remesh on a plane - only 3d meshes - most likely it's the lack of depth that means the remesh doesn't see it. You could try a Solidifier modifier first, then Remesh and then, if it works, scale it back to being a single surface and merge duplicates to remove the duplicated vertexes.

@Fuboski Added the file to my post, I've tried Remesh (including making it solid as Rich suggested), and Grid Fill, but no joy.

Step 1: Creating a large mesh of 1x1 squares
There are several ways to accomplish step 1, here's one possibility:  Create a new 1x1 square as a new object.  Use the "Array" modifier to make a row of 1x1 squares, wider than your target object.  Apply that modifier, then use a new "Array" modifier (set to Z offset instead of X) to make multiple rows, taller than the target object.  Apply this modifier as well, and "Merge Doubles" on the resulting mesh of 1x1 squares.
You should end up with a mesh of connected 1x1 squares, that extends larger in all directions from the target object that you hope to cut.
Step 2.  Use Knife Project
With your large mesh selected in Object Mode, shift-right-click on the original target object, to multi-select that.  The target should be "active" selected object, with the new mesh a reddish-orange multi-selected color.  Enter "Edit mode" on the target, with all vertices selected.  Set your view to look along the axis perpendicular to the meshes (typically, numberpad 7, 1, or 3).
Finally, click the Knife Project button in the left margin.  This should cut a batch of 1x1 squares into your target mesh.

I used the Sverchok add-on (visual coding for geometry)

the node setup

This generates:

A temporary plane that is subdivided n*n to match the given object's boundaries. (this you must tweak manually in this setup, but it could be done automatically)
For each polygon on the new subdivided plane it generates a point at the center of that polygon, and an identical point but with a z-offset. These pairs will form the start and end of a ray.
then it raycasts each point and generates a list mask (True, or False) of which rays hit something in the scene.
This mask list is used to discard those polygons in the subdivided plane that were not struck by the raycast

here's the gist that can be imported into sverchok from the sv import panel
https://gist.github.com/eea1bc4a29f6c983b408593fce44da74
Slightly more automated
Similar to the above setup, but finds the bounding box and uses the XY offset to place the start of the subdivided Plane automatically. All you need to do is adjust the number of sections X,Y in the Plane generator (but that could be automated too)

https://gist.github.com/d0e256b7b477f1641a50f13585f39d93
you'll have to press 'Get Selection' in the Objects-in node

Particle System

create a Plane with radius 0.5
add a particle system to your Ngon
set the grid resolution to number of divisions on the longest dimension
set the Dupli Object on the Ngon particle system to the Plane
ctrl + shift + a to make duplicates real
in Object Mode on the Ngon, press Make Local -> Selected Objects and Data

but who wants to manually do all that nonsense.. here's a script. It assumes a few things.

the plane is on XY
the geometry is nicely constructed by 1 x 1 elements
there is no other object in the scene other than the Ngon. (not even hidden stuff)

here:
import bpy

def quantize(original_obj, numdiv_shortest_side):

    bpy.ops.object.visual_transform_apply()

    # make a plane
    bpy.ops.mesh.primitive_plane_add(radius=0.5)
    plane = bpy.context.active_object
    plane.select = False

    # add particle system to original object
    ps = original_obj.modifiers.new("grid particles", type='PARTICLE_SYSTEM')
    psettings = ps.particle_system.settings

    # particle settings
    psettings.distribution = 'GRID'
    psettings.emit_from = 'FACE'
    psettings.physics_type = 'NO'
    psettings.grid_resolution = numdiv_shortest_side
    psettings.use_render_emitter = True
    psettings.show_unborn = True
    psettings.use_scale_dupli = True
    psettings.particle_size = 1.0
    psettings.render_type = 'OBJECT'
    psettings.dupli_object = plane

    original_obj.select = True
    bpy.context.scene.objects.active = original_obj

    bpy.ops.object.duplicates_make_real()
    original_obj.select = False
    bpy.ops.object.make_local(type='SELECT_OBDATA')

    # find first of the new objects, to join the rest onto
    joiner = None
    for obj in bpy.data.objects:
        if not obj in {plane, original_obj}:
            joiner = obj
            break

    bpy.context.scene.objects.active = joiner
    bpy.ops.object.join()

    # deselect everything
    bpy.ops.object.select_all(action='DESELECT')
    bpy.context.scene.objects.active = None

    plane.select = True
    original_obj.select = True
    bpy.ops.object.delete()

    # enter the remaining object and remove doubles
    bpy.context.scene.objects.active = joiner
    bpy.ops.object.mode_set(mode='EDIT')
    bpy.ops.mesh.remove_doubles(threshold=0.0001)
    bpy.ops.object.mode_set(mode='OBJECT')

original_obj = bpy.context.active_object
numdiv_shortest_side = int(max(original_obj.dimensions[:2]))
quantize(original_obj, numdiv_shortest_side)

craziest script i've ever written I think..


text:
Cycles - Baking Transparent Background
So I tried a few different answers that I found here, and I feel that this is possibly a duplicate question, but everything I have tried from the other solutions hasn't worked.
Basically I am trying to bake a material to a texture that will be used in Unity, but every test gives me a black background image.
In the image below, the top image texture is the mask (black and white, white being the leaves), and the bottom image texture is the colour.

It is currently not possible to bake directly to an alpha channel as you mention.
https://blender.stackexchange.com/a/41904/28015
There are workarounds, though, like you could bake only an emission shader of the masking (in this case you already have the mask so there's no need for that), then make it the alpha channel in the compositor.

Here is the blend:

Just bake the texture, update the compositor, and finally, go the the viewer node in the uv editor.

What you should do is, creat a new texture in the uv/image editor and change the color from black to transparent by sliding the alpha value. Then in your baking menu disselect clear. This now should give you your leaf with a transparent background once you've baked it.

I gave that a try, and I still get a black background.  I've uploaded my blend file and added it to my post if that helps.  Thanks

I did some testing around: first of my method doesn't work on your blend in Cycles but it does work in Blender Internal (Blender Render). Why this won't work is out of my range. It might be that you accidentally did something that is hindering it from doing.

I don't know if this can help you, but what works for me is this. I did 2 bake textures, 1 the regular bake texture, and the other is just a glossy bake type, only the color and that created a B&W image that then you can use as a mask in photoshop...


text:
Blender cycles, apply textures through a python script
I am trying to apply textures through a python script. I would like to use blender cycles renderer. I thought following these advices would be sufficient, but sadly Blender does not show the equivalent python commands when applying manually the procedure. How would you do this ? Or, is it possible to force blender to show the python commands ?
Thanks in advance

Some related answers Cycles - How to add nodes to a material?, Control Cycles material nodes and material properties in Python, Create an image node via code

This script does not do any unwrapping. List of available nodes
import bpy

mat_name = "MyMaterial"
image_path = #...

mat = (bpy.data.materials.get(mat_name) or
       bpy.data.materials.new(mat_name))

mat.use_nodes = True
nt = mat.node_tree
nodes = nt.nodes
links = nt.links

# clear
while(nodes): nodes.remove(nodes[0])

output  = nodes.new("ShaderNodeOutputMaterial")
diffuse = nodes.new("ShaderNodeBsdfDiffuse")
texture = nodes.new("ShaderNodeTexImage")
uvmap   = nodes.new("ShaderNodeUVMap")

texture.image = bpy.data.images.load(image_path)
uvmap.uv_map = "UV"

links.new( output.inputs['Surface'], diffuse.outputs['BSDF'])
links.new(diffuse.inputs['Color'],   texture.outputs['Color'])
links.new(texture.inputs['Vector'],    uvmap.outputs['UV'])

# distribute nodes along the x axis
for index, node in enumerate((uvmap, texture, diffuse, output)):
    node.location.x = 200.0 * index

Thank you for your answer. I am not sure I fully understand: how to apply the texture to an object? Why doesn't blender show the "python commands" when manipulating textures for the cycles renderer?

Couldn't you just do nodes.clear() instead of looping and removing them? Also, is there a way to auto-layout them after adding them? They're positioned on top of each other otherwise.


text:
Massive Frame Rate after rendering
I'm rendering using 720p, with 2000 FPS. After rendering, I'm getting a huge file with 244 frames/second. The source files are only 29.97 frames/second so why is the render going up almost 10 times???

What exactly are you rendering? A 3D scene? Compositor? Video Sequence editor? You say your source files have 29.97 frames per second and you are rendering with 2000 (?) frames per second, why such an unusually high value, more than 60 times the original value? What were you expecting would happen to file size with such high frame rate?

Do you mean 2000 frames (not frames per second).

Rendering video thru the NLE

Check your render settings. To get 29.97 fps you should have a framerate of 30 with a framerate base of 1.001. If you change the base to 0.123 then you will get 243.9 fps

I am rendering videos thru the NLE.

I added a screenshot of my Dimension and Encoding menus

My video length is 2:15:58 but when I render say, 10 mins of video, everything comes out just fine. It's only after I render the full length that I get the huge rates

Interesting, current releases have a max frame count of 300,000 (for 2.77 it has been increased to 500,000),  I wonder if exporting large frame counts to video has a bug. Can you find a frame count where this starts happening? If you export using other codecs does the same thing happen? I would report this as a bug and see if the developers can find a cause for bad frame rates with longer videos.

How can I look for that? Render it out 10 mins at a time?

I would just pick some frame lengths to narrow it down. We expect 244,000 fails does 200,000 fail? does 150,000 fail? depending on the time to export each step you could use closer frame lengths to get as close as you can. Of course we expect the error to happen close to the 244,000 frames used not with anything over 50,000

I have submitted a bug report to blender and uploaded some of the files. https://developer.blender.org/T47844

https://developer.blender.org/T47844
After more than a week talking to some guys, it appears the problem is not the actual video itself, rather the way Windows is reporting the status.


text:
Mesh disappears partly while sculpting
while sculpting a terrain model most of the time cannot see what I am sculpting as the mesh "disappears" on the location I am sculpting and somewhat around it but not the complete terrain mesh. Any suggestions what the cause of this is? I am using Blender 2.78a.
Here's a video of what I am seeing:
https://www.youtube.com/watch?v=oQ97_FNFhlQ&feature=youtu.be
Thanks

That link looks very sketchy, could you please upload to a trusted long-term video hosting site like YouTube?

@veryRandomMe I believe it's just it's OneDrives short link.

Ok, I solved the problem by correcting the clip end distance (under View) in the 3d viewport. It had an erroneous value of 5000km. After changing this to 10 km the mesh did not disappear anymore while sculpting.

@Niuskir thanks !! This issue was driving me crazy.

Look if you have an unused modifier on the object, I had the same problem and it solved it.


text:
Visualizing a 4D object in 3D space using Blender
Out of curiosity i am trying to visualize a 4D object in 3D space in Blender. I got the idea from and used some parts of the work done by Oleg Rybkin which can be found here: https://github.com/orybkin/Tesseract.
Using Python i extrude a standard Blender 3D object to the 4th dimension and by generating the 4D vertices, 4D Edges and 4D polygons of the 4D hypersphere.
To get the 3D view of the 4D object i use the Algebraic Form of the line-plane intersection formula described in (https://en.wikipedia.org/wiki/Line%E2%80%93plane_intersection) to determine the intersection of each 4D edge (consisting of 2 vertices each) with the 4D space defined by vertex [0,0,0,0] and normal [0,0,0,1].
I then disregard the fourth dimension completely of all the computed 4D intersections to get into the 3D realm (x,y,z,w -> x,y,z) and add 3D intersection in the Blender 3D Viewport and a ConvexHull Geometry Node to generate a 3D object.
The 3D object object generated in the Blender Viewport (no translation/rotation of the 4D object) i get is the same as the original 3D object (Cube, Sphere, Icosphere) which i believe is correct.
Unfortunately when translating (no rotation) a hypersphere in steps along only the w axis (4th dimension) I see the 3D sphere suddenly appearing 100% in size (when the 4D hypersphere enters the 3D subspace at w=0) and disappearing completely (when leaves the 4D hypersphere leaves the 3D subspace) while i should be seeing it appear gradually from from size 0%->100% and then gradually disappear from size 100%->0%. Rotating the 4D hypersphere also gives a 3D object which does not seem right (See this YouTube video on what i should be be seeing: https://www.youtube.com/watch?v=0t4aKJuKP0Q).
I believe the problem must lie in either or both: (1) the line-plane intersection method i use to get the intersection vertex between all the 4D edges and the 4D space defined by vertex [0,0,0,0] and normal [0,0,0,1] and/or (2) the method i use to reduce the 4D intersection vertices to 3D.
Here's the Python method to get the intersections (segment = 4d edge, 2 vertices, normal = normal of 3D subspace = [0,0,0,1]:
""" Find the intersection vertices """
def edge4D_4Dplane_intersection(segment,normal):
    # find a point at the intersection of a realm and a segment
    # in case when the entire segments lies on the realm, returns two endpoints
    # segment is given as matrix 2x4
    segment=np.array(segment)
    # adapted from wikipedia https://en.wikipedia.org/wiki/Line%E2%80%93plane_intersection
    direction=segment[1]-segment[0]
    length=np.linalg.norm(direction)
    direction=direction/length
    if abs(direction.dot(normal)) < PRECISION:
        # segment is parallel to the realm
        if abs(segment[0].dot(normal)) < PRECISION:
            # segment is parallel and contained in the realm
            return segment
        else:
            # line is not intersecting with the realm
            return []
    else:
        # line is intersecting with the realm
        d = ([0,0,0,0]-segment[0]).dot(normal)/direction.dot(normal)
#        d = (object_origin4D_transformed-segment[0]).dot(normal)/direction.dot(normal)
        if d >= 0 and d <= length:
            # segment is intersecting with the realm
            vertex=[segment[0] + d*direction]
            return vertex
        else:
            return []

I believe this requires a more of a Geometric/Clifford Algebra answer. Even though i followed many YouTube presentations and read publications on this i was not able to find the concrete formulas given the 4D vertices/edges/polygons i have access to in Python.
Below a YouTube link which shows some examples of what what i am seeing (Blender 3D Viewport render) now using the methods described above. The video shows in sequence 3 rotations and 1 translation of a hypersphere (w in steps from -2.5 to +2.5 Blender units). As you can see with the translation the 3D sphere suddenly appears 100% as the translated hypersphere enters the 3D space and disappears completely when the hypersphere leaves the 3D space located at w=0.
https://www.youtube.com/watch?v=4iydz5ZvxB0
Any suggestions on improving the methods used or a nudge in the right direction is much appreciated.

It is clear this question has no easy answer.  In the mean time using "logical brute force" python programming (so not using Geometric/Clifford Algebra) i made a Blender add-on which allows you to create a specific 4D object and transform (translate and rotate) trough 4D space and visualize what you would see in 3D space when the 4D object transforms trough this 3D space. See https://youtu.be/-uN1YjbK5no. The Youtube text of this video also has the Github location of the add-on.


text:
Grease Pencil stroke disappears
Everytime I press D + LMB I see the pencil as cursor and the indication that I'm about to draw something, but every time I draw a line, the line disappears.

You need to give a lot more information...for example, what pencil (I am guessing grease pencil).

Yes grease pencil. It was working until I switched to Object mode.

You mean you were in Grease Pencil mode?

Are you using the RetopoFlow add-on by any chance? If so sometimes grease pencil won't work on an active object. You might have to export the object then reimport it. I was having the same issue and that was one fix.

If your object is set to x-ray mode, the grease pencil marks will vanish.

You probably drew on a different frame of animation.

Check to make sure you don't have the [Grease Pencil layers] and [Grease Pencil Colors] set to invisible (eye icon).  I spent an hour trying to figure out why, but forgot that I turned them off.
For the new players:
N to open the right hand menu.
Uncollapse the  ▼ ☑Grease Pencil and ▼Grease Pencil Colors
Look to make sure the eyes are visible for both layers.  Also try creating a new Grease Pencil layer and seeing if that fixes any issues.

Double check the opacity of the active layer. If it's set to zero, the created stroke won't be shown after drawing, by it will be visible when drawing

I'm using a 3D mouse for zooming, so my grease pencil drawing planes are created in weird angles. As a quick fix, I set Scale Y to $0$.
When I then draw a stroke, it instantly shrinks to an invisible point at the drawing plane origin.
This does not happen, if I set Scale Y to $0.001$

Edit:
Just found a better way to fix the grease pencil drawing plane angle.
Change the option at the top of the drawing window from View to Front (X-Z).

Had this same issue and fixed by setting y-scale to non-zero.  Is this a known bug?

Check to see that you didn't accidentally go to a new frame in the dope sheet.

I am using a mac mini m1 and I had this issue while I tried upgrading to 3.2.1 from 3.1.2 but this seems to have been occuring intermittently and leaves me with no clue if I have done anything wrong.
Solution: I updated my version with 2.93.9 LTS version and this has resolved the issue for me.
Hope it helps.

Another possible cause is that Thickness Scale is near 0 for that layer.
Try to increase the value.

I met the same problem today.Maybe you pressed H accidentally. Go to the edit Mode and then try press Alt+H see if it works.

This is a bug, and not fixed. Try installing the new version of blender. I have two different blenders installed on my pc, and one always has the bug while the other doesn't. So reinstalling or updating will fix the bug I guess.

I had the same issue and was that the Grease Pencil stroke was created at a specific point in the timeline, so just grab the time marker and check in which frame the strokes were created.

Be sure that X-Ray mode is disabled on the object you are drawing on. Having it on will make the object's geometry draw on top of any grease pencil strokes you make on it.

This happened to me, turned out I was drawing on a frame that was within the boundary of ithe Time Offset modifier.
The strokes would show up in Edit Mode, but seemed to disappear while in Draw Mode.

I just had this problem and found that it was caused by being in Wireframe shading mode. I just switched from Wireframe to Solid and it works correctly.

Maybe in somehow your stroke keyframe location changed!
check the time line or the dope sheet, i found mine in 173


text:
Blender Materials When Using .blend file in Unity
not sure if this should be here or in the Unity section of SE but here is my problem.
When importing an .blend file into Unity my material is the default grey one. When I look at what has been saved from Blender there is a material folder but they are all the grey one. I have only once been able to save a material correctly and I'm not sure how I did it, so I believe there is a way to save a .blend and export the material information as well?
Thanks in advanced for the help :)
edit: Just to add, the materials are saved in a folder called Materials in the same directory as the .blend files.

Just in case anyone else comes across this and needs an answer, I found that Unity and Blenders materials are not the same, when importing a material from Blender into Unity, Unity will try to create a material as best it can from the Blender one but it is never exactly the same, so it seems it is best to just re create them in Unity.

Yes, I'm finding this to be the case as well. Simple flat colored diffuse materials come into Unity with the proper names, and are attached to the proper triangles, but the diffuse color is reset to grey. If I name the colors properly, I can target them in Unity and reset the Albedo diffuse color to what I wanted and everything looks right. So close, and yet so far! Feels like there must be some way to get the color to sync up as well, but I guess UV mapping is the go-to methodology and perhaps this isn't so important?


text:
Not able to select Blender shader nodes
Not able to select or move the shader nodes in shader page, whenever  LMB is pressed it shows an error saying "Nothing to erase". Not really sure if I have accidentally pressed any keyboard shortcuts.

press T key, you should see tool selection on the left, take a screenshot then. You probably have annotation eraser chosen instead of box select.

I corrected the case, because I have scripts for that making it extremely easy to do. Please don't use all capitals. Formatting the questions in a uniform readable manner will increase the chances of getting help quickly. All caps will only attract comments like this one or might even  get you unnecessary down-votes.

@MarkusvonBroady, thank you it worked

@MartynasŽiemys, thank you.

Apparently by accident (keyboard shortcut) you've switched active tool to the Annotation Eraser. The default tool is called the Selection Box, which you can choose in the Toolbar Menu , which you can open by pressing T or clicking/dragging small arrow in top-left corner:

Imgur mirror (SE image hosting has problems)


text:
How to unhide hidden objects with a Python script?
Here are a few objects that I have hidden:

I am using the script below to make them visible:
bpy.ops.object.hide_view_clear()

but it does not help.
So what is the perfect script to make them visible?

As of Blender 2.81, Object.hide_set() is working properly and seems to be the equivalent of Object.hide property in 2.7x versions.
Proof using the console:
>>> bpy.context.object.hide_set(False)

To unhide multiple objects you can run over objects in the scene and call the setter per object:
for o in ("Cube", "Camera", "Light"):
   obj = bpy.context.scene.objects.get(o)
   #if obj: obj.hide_viewport = False
   if obj: obj.hide_set(False)

You can also iterate through any given collection:
col = bpy.data.collections.get("Collection")
if col:
   for obj in col.objects:
       obj.hide_set(False)

Whatever you like...

Is it possible to simulate the Shift+Mouse_Click for hiding an object with its children. Now I am iterating over the children objects and hide_set(True) them individually. My guess is that under the hood is the same procedure that is happening but I was wondering if someone can just call the build in functon instead of re-implementing it.

Hi! Shift+LMB is reserved for multi-selection in the outliner. I recommend ask a new detailed question referring to this one @ttsesm

I see, thanks. I will open a new thread.

You need a way to specify which objects to unhide. Hidden objects cannot be selected, so you cannot just use bpy.context.selected_objects, you can use their names to identify them or whatever other attribute. You will need to loop through the objects from which you wish to pick the ones to unhide, you could use bpy.data.objects to do that for all scenes, but bpy.context.scene.objects are all the objects in the current scene that you are more likely to wish to work with. The script picking them by name could be something like this:
import bpy

for o in bpy.context.scene.objects:
    if 'Cube' in o.name:
        o.hide_viewport = o.hide_render = False

Note that there are a few ways to hide objects. object.hide_viewport or object.hide_render or object.hide_select
You can find out stuff like that using autocomplete functionality of the Python console (ctrl+space while hovering mouse over Python console panel with some text you started typing):

C is short for bpy.context in the console. C.object is the active object.

Also working somehow but the icon in the outliner doesn't change... I think it is still unfinished or they forgot to remove the properies, I don't get it.

If I am not mistaken in some development builds it was removed and now it is back. I assumed this is in order to be more compatible with older scripts. There is nothing about it in the documentation, it's just there so I assume it is fine to use this as we always did. Maybe the new way is more efficient...


text:
Is there a way to fill tiny holes leftover when joining meshes together?

I merged/joined some planes when transforming them with the polytool. I saw that this 2 tiny holes were left. Is there a way to fill them or get rid of them?
edit:
Here is the file: https://drive.google.com/file/d/1dXx1yfb26n3zDAgd4fUslDRNZp3yxl_c/view?usp=sharing
I must confess I'm a beginner in Blender, so expect funky stuff.

Can you tab into edit mode, take a screenshot and add it to your question? I am asking you to do this so I can take a look at the geometry of the mesh. Sharing your file will also be very helpful.

I agree with @Ribbit12 that a look at the geometry in Edit Mode would be helpful, because the way the mesh looks is essential for answering this question.

@Ribbit12 Hi, I added the file.

Depending on what you want to do with the object, having this shape as one big N-gon is perfectly fine and there is no need for complex rebuilding. First get rid of the Bevel and Build modifiers on the object. Then do the following:

In Edit Mode, select the sphere and the ring and press H to hide them.

Now select all visible geometry by pressing A, then choose M > Merge > By Distance to get rid of double vertices.

Deselect all with Alt+A, then select the central vertical shape by hovering the mouse over one corner vertex and pressing L. Then delete it with X > Delete > Vertices.

Now enable the Snap tool (the magnet symbol at the top) with Snapping > Edge (the dropdown menu next to the magnet). Select one top corner vertex of the trapezoid shape in the center, double-tap G to use Edge Slide and move the vertex towards the edge of the wing close to it until an orange circle shows you that it's snapped to the edge. Do the same with the other side. Left vertex to left edge and right vertex to right edge.

Now do the same accordingly for the large wings. Select one of the inner vertices and double-tap G to edge slide it down until it snaps on the corner vertex of the trapezoid, then repeat it for the other side.

Again, you can now select all vertices with A and merge all doubles by pressing M > Merge > By Distance. After that, select the four vertices around the empty space in the center, then press F to create a face between them.

That's it, you could now select all faces and hit F to join them to one single N-gon or leave it like that, whatever you need. To unhide the invisible geometry, press Alt+H. I would then recommend to select all vertices with A again and once more choose M > Merge > By Distance because there are more double vertices in this geometry as well. Of course you could do this with all vertices right at the beginning, I was just focusing on the central shape in my instructions.

Thank you very much for this detailed step by step!

In this answer, I am going to guide you through GIFS to rebuild your mesh, so that it has good geometry. There are too many overlapping edges and your mesh is made up of several other disconnected objects. The geometry of a mesh is very important. We need to try to maintain a good geometry for texturing, UV unwrapping, adding modifiers etc.
Final Result(without build modifier):

Final Result with build modifier:

STEP 1

STEP 2

STEP 3

Edited File:
https://drive.google.com/file/d/1wERFUuV24M1OgDqgqKXYDXhGrkSzIZvj/view?usp=sharing

Thanks! I can just select one "solution", but I appreciate this too.

No problem,to be honest Gordon's solution was definitely better :)

The only thing I can think of is either:
Selecting the edges and pressing  F to make a face
or Alt +  F if it fails (this will create triangles).
Merging them using Mesh > Clean up > Merge by distance. These are both not ideal solutions however as they can cause bad topology, especially if subdivided. If you mirrored it using the mirror modifier check your merging distance.

Apart from maybe creating bad topology, as I said in the comments it depends a lot on how the mesh actually looks like. If you take a look at this picture: https://pasteall.org/pic/16b110d9084846638dba509609fc020b the object on the left and right look absolutely the same in Object Mode (top row), but the meshes are completely different in Edit Mode (bottom row). It depends on how the object was created. With the object on the left, none of the solutions you've given will work. You can neither select edges and press F nor can you merge by distance.

As Gordon mentioned in the comments after taking a look at @dawns file this method can never work with his mesh.

I had no idea sorry, a blend file was not provided when I rambled

@Sven_ That's why we commented we need more information before we could give an answer ;)


text:
How can I render the effect of "transparent" lenses in glasses to use in other software?

I want to render that effect, but when I do it they simply transform into a solid texture. I'm using Eevee
Nodes:

Hello and welcome.  Can you [edit] your question to provide some additional info?  Which rendering engine are you using?  What does the lens material node tree look like?

@AllenSimpson Done my friend.

Thanks!  I'm really no good with eevee, just getting into it recently, but I'm sure someone will have an answer for you.  I do remember there being some settings for glass in Render Properties.

@AllenSimpson Which render do you use? Cycles? I can do it in Cycles. I'm still new to Blender, just trying to get stuff out :~)

Does this answer help? - https://blender.stackexchange.com/a/162826/110840

have you enabled Blend Mode > Alpha Blend in the Material > Settings?

Do I understand correctly that you want to "bake" the transparency and refraction als some kind of texture, to export it into another software that doesn't support realtime refraction?

@haarigertroll woah woah take it easy, I'm new to this.

@dawn: Sorry, I was just trying to better understand what you are trying to do.
Let's try again: As far as I understand, you are happy the way it looks in blender, but want to export this look into some other software?

@haarigertroll Exactly. In my noobness I want that to happend, but in reality I don't know if it's possible or is it hard.

Then, I am afraid, this won't work. Rendering a transparent effect to a static texture will only ever work from one given angle. To my knowledge, there is no way of pre-rendering refraction for 3D-engines that don't support refraction. Could you tell us, which applications you want to export your model to?

@haarigertroll Max 8, with Jitter


text:
Blender Viewport Shading mode Is showing a blurred object
I can't figure out what I'm missing. Stepped away from Blender for a few months and now I opened a new general scene and went right to Viewport Shading and the object is blurred. Notice that you can see through,like it's transparent, the orange framing of the object. I tried this in 2.83 and also a new install of 3.31.  Touched nothing after opening Blender but just clicked on the Viewport Shading icon on the top right.
Edit: Maybe I should say what I'm expecting to see. An opaque grey box. The default scene has a bulb above it and this is the same PC I used in the past.
Attached is the opening screen I see after clicking Viewport Shading:

That looks like a graphics card driver problem. Have you tried updating it?

Somehow my Radeon Driver didn't auto update. Thanks @John Eason for the solution! After upgrading the Video Card driver, and rebooting it functioned correctly.


text:
Node group that doesn't touch a certain attribute
I'm trying to figure out how to create a material node group that only affects certain Principled BSDF values.
As a simple example I have a cube in which each of the 6 planes have a different Base Color.  Let's say I want to create a group and leave the Base Color alone but only be able to change the roughness together on all the 6 sides.
I'm doing something wrong in my testing. When I create a group from one single side, and use that across the remaining sides, it is setting the Base Color to all the sides to the first selection when I want to leave all the Base Colors alone.
More Information:
Photo included below.  Maybe another way of asking is let's say I have an object with lots of surfaces all a different color and I want to change all the roughness, IOR, transmission simultaneously. I can then change each of the 3 properties until I get the desired look around the whole object without having to go into each surface individually. Is there another way to do it without using a node tree group.

Still having problems. See animated GIF link below for attempt 2 using Markus von Broady tips:
Test 001 animated GIF steps
Thanks!

You may have a wrong understanding of how the shading pipeline works. Show your current setup (node tree).

Thanks @MarkusvonBroady I've added an image and tried to restate the question in another way.

Still testing.  @MarkusvonBroady. Off topic question: What app did you use to record that section of the screen and what app if not the same did you use to convert it to animated GIF?

ShareX https://getsharex.com/

Thanks @Markus that looks like another toy for my collection.

Shared Custom Group
You can use a shared group that exposes sockets that are supposed to be material specific, while using its own values for shared stuff.

To easily isolate some sockets from the Principled BSDF, connect the sockets you want to isolate to some nodes (here: only base color). Then select the Principled BSDF together with one more node (it can be any temporary node; it doesn't have to be connected, but I did connect it as it will be useful when I hide sockets). Then select the Principled and the one additional node (here Value node), and press ✲ CtrlG:

Optional step: Now in the Custom Group, you can hide some sockets, by connecting everything to the sockets you don't want to hide, and with the Principled BSDF node selected, pressing ✲ CtrlH. You can also right-click the node and choose "Toggle Node Options":

 Those aren't really things you want to do for your own projects, I
do these steps for educational purposes to get rid of irrelevant
parts…

Remove the temporary node and press ⭾ Tab to exit the custom group; there you can also remove another temporary node:

You can now also "Toggle Node Options" for the custom group, copy-paste it to other materials, and everything inside the custom group will stay synchronized:

Of course you can expose all values and just disconnect some when you decide you want them all to be shared.

 Using this technique will make the shared values (here: metaliness)
shared among all polygons using the material. This means that if you
want to share only within a single object, you need to use a different
Custom Groups for other objects.

Driver
You can copy one of the material's values as a new driver, and paste that driver to other material's values. It can be hard, however, to remember which material you're supposed to modify, so you may consider creating a new custom property instead:

 It's a little misleading I used an object's custom property, even
though (as you see on the GIF) a driver points to a unique place that
isn't updated when you duplicate an object - how could it be updated,
if new materials are not created? Unfortunately a node tree doesn't
have a way to know what is using it when it's evaluated.

Geometry Nodes
Unlike in shading, geometry node trees have modifier wrappers. This means that you can send data from the modifier to the node tree, and since modifiers get duplicated when objects are duplicated (modifiers actually can't be reused, they have only a single user), the drivers are also duplicated and updated to new targets:

Shared Custom  Group. That might be exactly what I'm looking for. There are so many instructions on Node Groups but I don't recall seeing anything like you have done with "Shared" Custom Groups.  Is there a video anywhere to get to that step you have in that first animation you posted here? I did try Google but to no avail.

@PPL select the Principled BSDF node, and press CTRL+G

you sliced/split that blender screen nice for your examples.  I can't say how many times I tried Ctrl+G on Principle BSDF which is the easy part to get a saved group but it's what comes after that which you demo in example 1 which allows the node group metallic slider to affect all the sides while not affecting the color. You can see one attempt I made in the new above linked video.

@PPL see answer edit.

Thanks again. Glad you made that initial step clear, I got lost in my attempts but one of my first couple dozen tries I set up something similar. That was a great gif addition to the instructions and I followed along! Though this can help at times, is there another alternative that I don't have to re-enter the color after I add the group to each surface? I have a sphere with a few dozen colored planes. I was hoping to not have to re-select the colors each time I attach the node group to each surface. Make sense?

@PPL you can hover over one color, ctrl+c, hover over another, ctrl+v.

Great tips getting me closer. Not quite solved yet but it was nice to get the consolidated steps very neatly laid out. I am going refresh my rough python skills and see if I can select the active object, all the surfaces on that object (seen that done in samples) and see how to enumerate and set the material values. With that if I need it more flexible I'll see if I can add a simple UI value slider for the 3 properties I want to set.

Great answer! Well illustrated and written very understandable even for me! +1

@quellenform if I know you, you liked the lightbulbs - you're into typography and small touches like that.

@MarkusvonBroady Even though I love such small details, I meant more the way you wrote, structured and illustrated it ;-)


text:
Camera rotating around the object in a regular way with python blender
I want a camera that rotates regularly around the object I have taken with the blender package in python, and I want to take the image of the three-dimensional object from certain angles at the time of this rotation and render it, I wrote a code in this way, but the rotation angle of the camera is not very healthy. Also, according to the size of the object I take, the object does not appear in the images I take from some angles. exactly what I want is to be able to do this process in a stable way, let the object be fixed in the middle and draw a flat circle around the camera and take an image. can you help me with this?
def rotate(point, angle_degrees, axis=(0, 1, 0)):
theta_degrees = angle_degrees
theta_radians = math.radians(theta_degrees)
rotate_point = np.dot(rotation_matrix(axis, theta_radians), point)

return rotate_point

def fit_camera_to_object(camera, obj):
# Calculate the bounding box of the object
bbox = [obj.matrix_world @ v.co for v in obj.data.vertices]
min_x = min(bbox, key=lambda v: v.x).x
max_x = max(bbox, key=lambda v: v.x).x
min_y = min(bbox, key=lambda v: v.y).y
max_y = max(bbox, key=lambda v: v.y).y
min_z = min(bbox, key=lambda v: v.z).z
max_z = max(bbox, key=lambda v: v.z).z

# Calculate the center of the bounding box
center_x = (max_x + min_x) / 2
center_y = (max_y + min_y) / 2
center_z = (max_z + min_z) / 2

# Calculate the distance from the camera to fit the object in view
distance_to_fit = max(max_x - min_x, max_y - min_y, max_z - min_z) * 3

# Set the camera location and rotation
camera.location = (center_x - distance_to_fit, center_y, center_z + distance_to_fit)
camera.rotation_euler = (math.radians(90), 0, math.radians(45))  # Adjust rotation as
needed

# Adjust camera height to fit the entire object
camera.location.z = max_z + distance_to_fit  # You may need to fine-tune this

def rotation_matrix(axis, theta):
axis = np.asarray(axis)
axis = axis / math.sqrt(np.dot(axis, axis))
a = math.cos(theta / 2.0)
b, c, d = -axis * math.sin(theta / 2.0)
aa, bb, cc, dd = a * a, b * b, c * c, d * d
bc, ad, ac, ab, bd, cd = b * c, a * d, a * c, a * b, b * d, c * d
return np.array([[aa + bb - cc - dd, 2 * (bc + ad), 2 * (bd - ac)],
             [2 * (bc - ad), aa + cc - bb - dd, 2 * (cd + ab)],
             [2 * (bd + ac), 2 * (cd - ab), aa + dd - bb - cc]])

def rotate_camera_around_object(angle, obj, axis=(0, 0, 1)):
Rotate camera around the specified object
cam_location = cam.location - obj.location
rotated_cam_location = rotate(cam_location, angle, axis)
cam.location = rotated_cam_location + obj.location

# Delete default cube
cube = bpy.data.objects["Cube"]
bpy.data.objects.remove(cube)

# İmport stl
bpy.ops.import_mesh.stl(filepath="C:\\Users\\acer\\Desktop\\stlfile\\a.stl")
stl = bpy.context.active_object
# Example: Set the location of the object
stl.location = (0, 0, 0)  # Adjust the location as needed

light_data = bpy.data.lights.new('light', type='SUN')

light = bpy.data.objects.new('light', light_data)
bpy.context.collection.objects.link(light)
light.location = (3, -4, 5)
light.data.energy = 200.0

# create camera
cam_data = bpy.data.cameras.new('camera')
cam = bpy.data.objects.new('camera', cam_data)

# Assuming 'stl' is your object and 'cam' is your camera
fit_camera_to_object(cam, stl)

constraint = cam.constraints.new(type='TRACK_TO')
constraint.target = stl

bpy.context.collection.objects.link(cam)

# create material
mat = bpy.data.materials.new(name='Material')
mat.use_nodes = True
mat_nodes = mat.node_tree.nodes
mat_links = mat.node_tree.links

stl.data.materials.append(mat)

# metallic
mat_nodes['Principled BSDF'].inputs['Metallic'].default_value = 1.0
mat_nodes['Principled BSDF'].inputs['Base Color'].default_value = (
0.005634391214698553, 0.01852927729487419, 0.8000000715255737, 0.01852927729487419)
mat_nodes['Principled BSDF'].inputs['Roughness'].default_value = 0.167

# Set the world background color (change to your desired color)
bpy.context.scene.world.node_tree.nodes["Background"].inputs[0].default_value = (1, 1,
1, 1)  # White background

scene = bpy.context.scene
scene.camera = cam
scene.render.image_settings.file_format = 'PNG'

for angle in range(0, 360, 10):
try:
rotate_camera_around_object(10, stl)

# Set the filepath to the same folder for each angle
scene.render.filepath = f'C:\\Users\\acer\\Desktop\\blend\\blender_{angle}.png'
bpy.ops.render.render(write_still=True)  # Render and save image
except Exception as e:
print(f"Error: {e}")

and the result is an off-centred object and a half visible object

Have you checked if your object's origin is correct?
if yes, wouldn't it be easier to set a "Track To" constraint to the camera? So it will have your object in field of view, and you will avoid a lot of computation

Thank you for the answer, yes the object looks correct when I view it. and I use the method you mentioned in this part of my code.
constraint = cam.constraints.new(type='TRACK_TO')
constraint.target = stl


text:
Can't grab edges in sculpting mode

I'm using blender 4.0. I can't grab edges it moving everything except them.

Why use Sculpt mode when a tweak like this can be done in Edit mode with proportional editing enabled?

Grab Tool in Sculpt Mode will grab vertices not edges.

I think i could grab bottom part before and now i can't


text:
my mesh is warping a bunch after rigging
ive never rigged anything before so if there's anything glaringly wrong with this lmk. theres a bunch of warping when im posing so i feel like i did something majorly wrong. i followed this tutorial. Rigging wont work
i did the dummy mesh, automatic weights, etccc
so maybe i misunderstood something. i would really appreciate the help. my original file is here (the stuff being used is on the veryy bottom of the outliner):

Please share your Blend file using the official web site rather than using an external site where it will not be available to future BSE users.  You can share it via https://blend-exchange.com/ following the instructions there to copy the full link on that page. Then edit your question here and paste the link into it.

The screenshot (other than not having enough clothes on) looks fine? Maybe a little stretching of the arm but idk what the problem is. I hope it is more obvious in the file… Will check it out later if I can.

@TheLabCat i think it is much more obvious in the file so yes pls if u can i would really appreciate it :)

The body mesh has flipped normals. Same problem as here (point 2) https://blender.stackexchange.com/q/273304/107598 and here https://blender.stackexchange.com/q/255069/107598. You can do Recalculate Outside (Shift+N) in Edit mode to fix it. Then rebind the mesh to the armature with automatic weights and it should work.

@Blunder Please flag this question as a duplicate if you believe it to be.

This question is similar to: Rigify armature won't move my mesh. If you believe it’s different, please edit the question, make it clear how it’s different and/or how the answers on that question are not helpful for your problem.


text:
UV Unwrapping doesn't appear to me. Is my file the problem?

Hello kind people! I'm totally new to Blender, have been watching tutorials and reading about it,  but right now I don't know what's going on.
After I did the autorigging in Mixamo, my character lost all its colors and textures, and I'm trying to give them back, but none of the options related to UV unwrapping appear, not even when I type it in the menu.
I don't know if the problem is in the file, nor have any idea what to do. Can someone please help me?

(Emir helped me with the first question <3 The other image is how it got after I corrected what he pointed out.)

Hello and welcome. First of all, you are in object mode, switch to edit mode to see if that solves you UV problem, second of all, it appears that you are in solid mode, change that to (keyboard Z) material preview

THANK YOU! <3 That changed things for better now! But please, if you can, take a look at how it is, I posted a new image in the question. Do I have to add more textures?

Below your File menu on the side of your UV map view, there is an icon of two arrow it is used as a synchronization between the UV and the 3D object, click that to see your UV map, or just select all the vertices on your 3D object see this
https://youtu.be/mmYJWMP_M4E?si=nB_pAC2qNE41Wh5l&t=156

It worked! At least I think so haha, because the character now looks clean and colorful in the UV editing, but when I go back to the layout, it still metallic. Which one do I trust? (I've added another image to the question).


text:
Why is FBX model all black in Blender after importing?
I'm learning Blender in order to animate, but I'm pretty new to all this.
I don't know what's happening with my character, it looks all black.
I'm kinda lost in my learning process, so, if you see some topic that I need to learn, please, feel free to tell me.

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

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

Hi Duarte! Sorry I couldn't reply sooner, I was at a camp with no internet on vacation. Here's where I got the model from: https://rigmodels.com/model.php?view=Claire_Girl-3d-model__LXG1NDL0BZ814059Q0RW9HZXE&searchkeyword=claire%20redfield&manualsearch=1              and thank you for answering me!

In some cases, (with imported models) the correct image textures are not connected to the shader node.  To fix that, just double-check the materiel in the "Shading" workspace.
Another problem I've encountered that causes the materiels to be black has a weird fix: you have to delete the image textures node in the shader, and then re-add it, (with the correct image) and plug everything back up.
Hopefully either of these are helpful to you!

Hi Aidan! Sorry I couldn't reply sooner, I will try to implement what you've suggested, thanks a lot! :D

Hey, no problem.  Hope it works!


text:
How to get the index of specific value in geonode

I want to obtain the index that has a value of true, in a single frame.
In this pic, for example, the result would be 8, how do I do that?

(Using Blender 3.6.8)
Without any assumption about how many points with a value of True there is, a Separate Geometry node can extract a geometry with only such points (green graph part).
The case where there is none is treated by the blue graph part. A Domain Size node is counting how many points are extracted. If it is 0 (i.e. not Greater Than 0), -1 (i.e. an invalid Index value) is returned by the Switch node.
The case where there is at least one point with a value of True is treated by the red graph part. From the selected geometry, the first point position is recovered through a Sample Index node set in Point domain. It is to notice that the Index value is hardcoded to 0, to pick a single point even if more than one point were selected. Eventually, a Sample Nearest node on the original geometry at this position is returning the Index of the point of interest. Be aware that the Separate Geometry node might re-index points and consequently the first extracted point might not be the first tagged point in the original geometry order, if there is more than one.

For the demonstration, the point of interest is defined by its Index through the Group Input node, and the boolean to tag it is computed by a Capture Attribute node. The Viewer node should returned the Value entered in the Properties editor, or -1 for out of bounds values.
Resources:

Too much belt-and-braces , I suppose, but as a supplement, you could use Accumulate Field (1) to check there was only one True element.

@RobinBetts: I appreciate your "belt-and-braces" mindset shown in your answers ! I took the opportunity of your comment to extend my first proposal, to deal with out of bounds cases (less or more than one True element).

Hehe... :) I guess GN is never going to be a 'safe' programming language, but we can do our best, where it's worth it.

You can also test against a value by comparing against it as an index.
In this case Blurred in positive and IndexofPoint is a Stored attribute that returns the Index number if Blurred is positive. Likewise you could use it to Switch between 2 values, in this case the Position.

Welcome to BSE! I think this doesn't answer the OP's question, because it just stores what you already have: index. But it won't tell you from outside the context of each element, what is the index of the element with a value of interest. Also notice the ambiguity for the first element.


text:
How I can apply noise texture shape animation on a geometry?
i'm a begginer with geometry nodes.
I created this simple noise texture animation with geometry nodes. I was trying to put in on a desired shape. I didn't found the solution. I was trying to create volume and plug it instead of volume cube node, but idk, its not working also.
Can you help me? Is it possible to do this?
Here animation is working. I wanted to put this on Suzanne.

edit
I have actually no idea how to connect that animation to a tree.

In which way is it not working on Suzanne? At the moment it cannot work on Suzanne because you neither have Suzanne in there via Object Info node nor have you added a Geometry Nodes modifier on Suzanne to directly affect it - and even if you had, there is no Group Input node in your setup to get the data from the base mesh which holds the modifier. It would be helpful to know what you actually tried to get it working on Suzanne. The screenshot shows nothing which could accomplish that task.

additionally you probably have to make sure that your Node Tree can handle your input type. Suzanne is a mesh. So instead of your Volume Cube node you probably want a Mesh to Volume node.

The issue with your second image is that Mesh to Volume - Density expects a single value (Float) for all voxels. So 3D texture is not accepted. Volume nodes in GN are quite limited at the moment so there is not a way to mix volumes here.  @GordonBrinkmann His first screen is showing working node-tree for Volume Cube node that is relevant input for mesh generation.

@vklidu Since she said in the question she wanted to "put it on a desired shape" and "wanted to put this on Suzanne" I was asking how this nodetree was supposed to obtain Suzanne as desired shape. If you put the GN modifier on Suzanne directly, she'll need a Group Input node to get the shape into the nodetree. If the modifier is on a different object (like in the screenshot), she'll need an Object Info node. Nothing of that is present. A Volume Cube does not provide any mesh data from Suzanne.

The issue with your second image is that Mesh to Volume - Density expects a single value (Float) for all voxels. 3D texture is not accepted. Volume nodes in GN are quite limited at the moment so there is not a way to mix volumes here. You would have to somehow create a volumetric shader and export as VDB, that can be imported for GN.
Consider if for desired result could be enough to use Noise Texture for Set Position node before (or after) Volumes ... sure, the result is not the same.

... or if any Volume is needed at all.
As suggested by Gordon - It would be helpful to know what is your goal, because another approach can be to add Empty Volume object into your scene, assign Volume to Mesh modifier (Object > Suzane), assign Volume Displace modifier with Noise texture ... and than add GeoNode modifier with Volume to Mesh node.