text:
How do I move vertices from the center without scaling?
I want to move a vertex from a 3D Cursor in a direction (vertex - center) ie from the cetner outwards.
I know I can achieve that with scaling the vertex position against the 3D cursor, but when moving the vertex by 1 unit I have to deduce the unit from distance.

When the vertex is 3 units from the 3D cursor and I want to move it by 1 unit. I have to scale the vertex by 1.3333...
Is there a better way to do this ?

Select vertex, press G twice and input the desired value.

If I understand the feature correctly. Pressing G twice will in case of circle just move the vertices clock-wise or counter-clock-wise. I need to move the vertice from the center outwards.

Blender being a mesh based 3D modeller is very lacking in this sort of precision modeling area. I'll try and think of something, but I don't think there is any easy way to do this currently.

If you only want to move the vertex inwards, you can use the Inset operator, if you don't mind the extra step of creating a temporary face with F then erasing all the surplus created geometry.

Try to use the Alt+S command, then type the desired value.

Didn't know about this, very useful. This is why a love BSE :)

@Duarte Farrajota Ramos your comment with the Inset concept inspired me to find this solution :). I didn't understand what the OP really wanted before you posted it.

This is perfect. Is is possible to lock the movement to an axis, similar to normal transform ?

@Melon Therapy I'm affraid it's not possible. Remember that my answer isn't a proper solution but some kind of workaround.


text:
Engrave Text onto an irregular surface
I've searched thoroughly and while there are plenty of questions and answers on how to engrave text into an object none seem to work for me as i am using an irregular surface.
I have the following Model

And when attempting to use a boolean modifier (The text has been converted to a mesh) with difference The following is the result:

Side View:

as you can see that hasn't come out at all as I wanted it
(I hoped it would only cut away what was inside the main model and fill the bottom as other answers have shown:
Here and Here)
Some Letters do cut correctly like the very first but the colours are still messed up.
So My question is, Is there a way to cut/engrave text into an irregularly shaped surface that sits flush with that surface.
Edit: File as requested:

also a side image of the model http://i.imgur.com/Obo1Df2.png, unfortunately i could not post in the main post as i dont have sufficient reputation

Added the pic to the post. Feel free to move it.

It may be worth trying to show the engraved details using the normal map. As to what I tried, it appears I should've increased the polycount of the main curved object up to 150k, which isn't good. And the shading still wasn't satisfying enough (only if the camera isn't that closely).

What is the topology of the main object (irregularly shaped one) ? It should be quite dense in order either Boolean or Knife Project to take (desirable) effect. You can increase the polygons' density only there so to save render times.

How would I go about doing this? sorry I'm very new to modeling with blender so I'm not very well versed

Your "staff" object has many duplicate vertices and all normals are inside, boolean can't work.

In Edit mode, A to select all, then press W > Remove doubles,
After fixing duplicates, select all, press Ctrl+N to fix normals
apply boolean modifier to object "staff" with type of Operation set to Difference, with object "Esvele"

In order to see the effect, hide object "Esvele" or set its "maximum draw type" to "bounds".

Adding pictures for the whole process...

I hope it is clearer now... you just have to set boolean for every other text, now, it will work and have the right color......

thank you very much. as I said I'm pretty new to this so id didn't think there would be issues with just duplicating the object and making it a mirror so they are one thanks for your help. only problem is when i press W I have no option to remove duplicates only to retrict render and clear restricted render

Is there perhaps a sub menu somewhere that I can rather use as I've noticed from alot of posts my hotkeys seem different

Edit: Turns out my version is hideously old (2014-04-10) so perhaps updating is in order

@kylehendry you should enter Edit mode to execute Ctrl+N and W operations in a described way.

attempted it again and when using remove doubles it says nothing was removed and after fixing the normals the same issue happens again

also is there anyway to fix that weird purple colour? i think its using the ends material instead of the staff but ive no idea how to fix it

double check doubles and normals, or the boolean will not work. Then that object has 2 materials "staff.003" and "jam" (jam is purple). After applying the boolean, you can assign those vertices to "staff.003" (just select them, select the material, and press "assign").  Before applying the boolean, those new faces (engraved letters) get the first material (jam). You can set "staff.003" as first, though.

see added pictures...

Thank you very much for your help. Only problem that remains is my computer is so bad it can't do the basic process of removing duplicates without freezing.

source: Stack Exchange

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

sort: votes


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Addon executes only after left click on window
I have written a script that interpolates the beginning and end keyframes of an animation intended to be cyclic in response to my own question here.
The addon executes just fine, but only after clicking in the Fcurve window. I mean, I select, in the fcurve window, some keyframe or keyframe range or keyframe set (the script will look for the underlying channel or curve selected), then I click in my addon within its menu and finally left-click on an empty space in the window for the script to render on.
So, how could I set or fix the script so that it executes when I click on it in the menu?
The code is in Github.
PS: I don't know if the preferred behavior is posting the whole code here or referring it by a link, sorry.

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


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Interpolation of animation cycle extremes
I'm working on a cyclic animation. I applied the F-Curve modifier Make Cyclic for better seeing what I'm doing. In the image you can see the f-curve for an specific bone. My question is, is there a way of interpolate the beginning and end of a cyclic f-curve?

I mean. Blender interpolates automatically the f-curve between 'START' and 'P', and between 'P' and 'END'. In the image, the interpolation in the interval 'i1' between 'START' and 'P' is made taking into account 'START', 'P' and 'END'. Nevertheless, the interpolation does not take into account the virtual 'P' that lies before 'START'.
I myself have tuned dozens of times the START and END points of every cyclic animation I have done because I haven't find any obvious way to do this. But this tuning is made on the fly, manually, by tweaking the handlers for the extreme keys of the animation. Is there a way to force Blender into interpolate the f-curve between P, START, and END treating 'START' and 'END' like if there were the same keyframe?
I have only found this post about the very same topic 4 years ago, but there were no solution and I don't know if any plugin, addon or functionality has been added since then (2012): http://blenderartists.org/forum/showthread.php?257538-Looping-an-animation-smoothly
Thanks in advance.
Edit:
I know one feasible workaround for this issue, as stated in the link above. I could make two copies of P and place them in the exact position the "Make Cyclic" transform calculates. It then would interpolate correctly. But I don't want this. It is a workaround that, applied to all the curves for all the bones for all my cyclic animations, is a real PITA. As also stated in the link above, I tweak here and there almost every keyframe in my animations, but I want to have the basis of a well done interpolation and not to lose hours tweaking start and end keyframes of every looping animation to make them look finely interpolated. I have read that 3DS has this feature. Is not an automagically feature like they say in the link. I just want the interpolation Blender does in every frame in every animation, but taking into account the cyclic nature of it.
Edit 2:
This is the page that describes the function 3DS that I talked about. Just for reference.
https://knowledge.autodesk.com/support/3ds-max/learn-explore/caas/CloudHelp/cloudhelp/2015/ENU/3DSMax/files/GUID-8D3FF404-082E-44D5-99B1-68F960A45D0D-htm.html

You have to set the end of the loop 1 keyframe before the very end of your animation, if the first and last Keys are the same then there will be a loop.

No, sorry, that's not the problem. The animation runs just fine, but the solution you posted doesn't affect the curves at all. I repeat, yes, START and END are the same keyframe, but the problem is that for 'i1', Blender interpolates taking START, P and END and for 'i2' it takes again START, P, and END. I want it to take -P, START, P, END for 'i1' and START, P, END and 2P for 'i2'.
I know that START and END are the same keyframe, but Blender doesn't. And so it doesn't interpolate the whole animation as a cycle.

I created a script that solves this situation by copying the second and next-to-last keyframes before and after the first and last keyframes, forcing the curve to interpolate and removing those keyframes leaving the interpolation untouched.
Here it is:
https://github.com/aravergar/cyclic-animation-interpolation

Thanks for the posts. This is not a regular forum, according to site rules links to answers are not answers if the link goes missing your answer becomes an empty shell without content. Answers should be substantial and stand on their own without relying on external data like links, videos or images. Instead of having users go through external links, either transcribe essential parts of the process here, linking the source, or posts these in the comments section instead.

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


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Dynamic cord for real time simulation [Blender -> Unity question]
I have a mechanical arm model with animations that I export to unity for a simulation game.
Now I need to add some cables and wires that move realistically with the robotic arm. Something like this just to demonstrate-
 https://www.youtube.com/watch?time_continue=7&v=QtVQ-NSms2A
How should I approach this solution?
Thanks.

Relate. https://blender.stackexchange.com/questions/109448/create-a-shower-hose-with-correct-physics/109453#109453

Hi Leander! Will it work in Unity though?

You'll have to bake it to bones before exporting it.

As in baking the animations? Not sure what that means bake it to bones. Is there a realtime solution to it?

Yes as in baking the animations if your going to export animations anyway, if you want a realtime simulation in Unity, then this question is not about Blender.

Leander, Can you get on discord?

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


text:
Blender 2.8: Where can I find light energy/intensity in Cycles?
I'm a super blender noob. I'm a grand total of 2 days in, so forgive me if this is a stupid question, but I've looked online, and can't find an answer.
Lamp intensity/energy seems to have been removed from the Cycles renderer in Blender 2.8, and as far as I can tell, nothing replaced it. It still exists in the Eevee render.
Since 2.8 is a beta, I first assumed that maybe it was a bug, but the docs mimik this change by listing "energy" as an attribute of lamps in the Eevee renderer, and not listing it for cycles.
https://docs.blender.org/manual/en/dev/render/eevee/lamps.html
https://docs.blender.org/manual/en/dev/render/cycles/lamps.html
I can't find any reference to "energy", "intensity", or "brightness" on the cycles page at all. BUT in the last section on Sun Lamps, in the last sentence, it does mention:

Because they are not located inside the scene, their strength uses
  different units, and should typically be set to lower values than
  other lights.

So shouldn't that mean that there is the ability to modify it's strength somewhere?
I can find plenty of articles discussing functionality of 2.7x, but the only other reference I could find about 2.8 was a comment on an unrelated bug, where someone said that they can't find the intensity setting anymore, and that it was probably removed.
https://blenderartists.org/t/2-8-light-bleeding/1130700/4
Was light intensity deliberately removed from Cycles in 2.8? And if so, how do I increase the brightness of a Cycles sun lamp?
Thank you,
-Yurelle
Update:
I do not believe this is a duplicate of this answer. While that post does make a passing reference to the cycles lamp strength, this description is not explicit on where to find this option. Furthermore, it is unclear what version of blender it is referring to. That question was answered in June of 2017, nearly a full year before Blender 2.8's first alpha was released (in June 2018), which makes it unlikely this answer was referring to v2.8. Since the confusing change I am asking about was (as far as I can tell) introduced in v2.8, that makes the old answer insufficient; or at a bare minimum not clear in it's answer applying to the newly overhauled version. As I demonstrated in one of the links in my original question, this change is something which has confused others, not just myself. And, my question serves as an explicit target & solution to that confusion. @Mahmood ul Hassan's answer provides a direct, clear, & explicit answer to the nebulous question, without required other asker's to interpret passing remarks in unrelated questions on ambiguous software versions.

Possible duplicate of Relation between BI and Cycles lamp energy/emission values?

Select lamp, click on "use nodes". There will be "Strength" that you can change according to whatever you like. Which increases or decreases the intensity. Its default value is 100 I guess

The "Sun" type has "Strength", but the other types have "Power". What are the units for these lights?


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How do I save my sculpture?
I created a person's head using sculpt, but when I go to Edit or Object mode, it just shows as a cube. I'm not able to apply modifier because when I try, Blender shows an error:

Constructive modifier cannot be applied to multi-res data in sculpt mode

Yet when I do it in Object mode, it remains a cube.
What to do?

Similar to a subsurf modifier, the multires modifier has settings that determine what level of detail is used for object mode, sculpt mode and rendering. If you only see a cube in object mode then you most likely have the preview set to 0, simply increase this to see your sculpt detail.
Note that the detail shown from the preview setting is used when you apply the modifier, which must be done while in object mode.

Prior to sculpting try the following:

Go into Object mode and add Multiresolution modifier.
Switch over to the Sculpt mode to begin sculpting.
When you're done go to Edit mode and check to see if the sculpting
figure is there.
If not then go back to Object mode and click 'Apply'
Then go back to Edit mode and the sculpted object should be there
now.


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How to convert Cycles materials into LuxCore materials and have textures still applied?
My problem is: I have made a model with materials in Cycles render with UV Mapping and Nodes. Now, I want to render through LuxCore, but my model is too bright.. noisy.. and without any of my textures !
I thought I had to ''convert'' my Cycles materials into a LuxCore ones, but I don't know how. I have no button '' Convert Cycles to Luxcore ''.
How can I convert my materials from Cycles render engine to LuxCore render engine?

When you use a different render engine everything changes, the lights the textures and all settings. There is no single button that just converts everything for you, Just like you have learned Cycles you need to learn Lux, they are different so now you need to go redo all your lights and textures in Lux.

Ok I understand ! I have to remake my UV Mapping Etc.. like a New project ! Thanks a lot for your answer !! I'm gonna see youtube tutorial... :) Have a good day, thanks !

When using a new render engine, many things will change in your scene. There will be an entirely new lighting system, your textures will no longer look correct (although all your UV's will still be good).
The render settings will be completely different, another engine will have different rendering features than Cycles. Render Passes will be handled different, the lighting values will drastically change and may not even work at all. Some render engines (in my case Renderman) requires you to use a separate program called "IT" to render to, you can no longer use your Blender view port to see your renders.
To sum it up:
You will have to redo all your lights, textures, and will have to learn the new settings to best optimize your scene. There is no button to just transfer everything to a new render engine.
Also keep in mind, you may not be able to use any GPU's to render out your scene, I am not sure if this is true for LuxCore but  this is the reason I quit using Renderman.

LuxCore supports GPU rendering.


text:
How to model multiple windows in a building walls?
I am currently going to model a building from a reference

The image i found.
I have an idea on how to go about modeling it but what I'm looking for is some help on what would be the best way to go about creating the windows as in this image. The windows go right along and down the building.

you should model the window, then use an Array modifier to repeat it horizontally and vertically, is it the kind of trick you're looking for?

im looking so that the window looks like it is part of the building and when i add a glass texture i want it so that i can be able to see through , wont it just show the building through the glass if i model it separate and attach it ?  novice question i know

You need to cut windows through the walls obviously, if wall doesn't have any hole window will be just attached to the wall. I'd suggest looking at some tutorials on modeling buildings, e.g https://www.youtube.com/watch?v=qJJRC2ebvSE


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Screen distorts after enlarging/opening new windows

This distortion occurs upon opening new windows inside blender, such that I can not save, save rendered image, open project, virtually anything. I'd really appreciate an answer on how to fix this issue, since it disables me from working in the app as a whole.

Also, when I open the app in full screen mode, the same distortion happens and after quitting full screen I am only able to work in the 3D viewport

That is graphic card drivers / non supported graphic card problem... Try to update drivers for GPU or use another GPU if your PC has one. Also to make screenshots use https://www.take-a-screenshot.org/windows.html

If your laptop is an Acer Nitro 5, then all models come with a graphics cards  from the Nvidia Geforce 10 series which are supported by Blender. Download the latest driver for your graphics card directly from Nvidia: https://www.nvidia.de/Download/index.aspx?lang=en


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Model Will Not Render
I am following a youtube tutorial to make a lightning animation. The youtuber repeatedly quick renders his model and is given a glowing lightning bolt against a black backdrop. However when i quick render the model all i get is a blank, grey screen. I am using the Blender render and have a camera as well as a Hemi light source in the model. I am relatively knew to Blender so apologies if it's a simple question but i desperately need help!

The model before rendering

The rendered model

please post the link to the tutorial.

Possible duplicate of Object not visible in render

Can you upload the .blend file to Blend Exchange?

Please include a screenshot of your render settings. My suspicion is you do not have a render layer set up.

Did you apply any materials to your scene? Did you set up a world background? Please edit your question and provide more details about what tutorial you are following.

Make sure the properties of light source is set properly and the light source is allowed to render in outliner

Ive gone over the lights properties but have found no issues and have even tried different light types to no avail

Maybe you would have restricted the light source from rendering

sorry to keep pestering you but do you know how i would rectify this issue

If this is a curve object, you'll need to make sure that you first convert it to a mesh. Make sure that the layer it is on is also allowed to render in the render layers tab.

Your problem aint solved yet?


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Adaptive subdivision modifier causes high memory
I'm modeling a bridge and because the scene is going pretty far in the distance  I decided to use the adaptive subdivision function.
I have an object that has an array modifier that repeat it self 100 times, the object has 32 verts what normally does not give me any problem to render.
Now if I render my scene its taking 15 minutes to even start rendering and blender is working on Building BVH <Object> and when its doing this my memory peaks at 12GB what is absurd for this scene.
What did I try:

disabling my HDRI and use a simple light setup.
removing verts up to where I had 4 verts left.
removing the material.

I have the feeling that I'm missing something.
Image of my modifier setup included

What is the vertex count in your scene? Is your camera very close to one of the instances that have adaptive subdivision on? Remember adaptive subdivision is only generated when you tab in and out of edit mode. The vertex count can crank up too high if you exit edit mode when zoomed close to the mesh. Go into camera view and tab in and out of edit mode before render.

The viewport in not the problem, its the render that generates the high memory. Total verts are 41,114.

Your dicing scale for rendering is 8-fold compared to view so even if viewport works well your render could be absolutely murdered by the generated detail level.

It seems to go away when I take another camera perspective. Well this is why its called experimental mode I guess.

It looks like you might be better off not using adaptive subdivision. According to the docs, this property makes muti user objects single user objects, causing increased memory.
This might mean that its separating each iteration of the array (which would make sense as each one needs to be subdivided differently.)
Another solution might be to shorten your array a bit, then manually duplicate the array and lower the subsurf level.
Just out of curiosity, what happens if you move the array below the subsurf? (Other than messing up your seams) Does that help with render times at all?

Subsurf after the array should be the proper order to do it. The docs say nothing about modifier-generated geometry that are not quite instances.

In my tests I found no difference between applying an array modifier or not when used with adaptive subdivision. Both render results are identical overlapping perfectly. Nor is there any difference in memory usage during rendering. Tested with 100 instances of 8-vert mesh. So I will have to disagree with the hypothesis made in this answer.

Ok cool, thanks for the advice. I rarely use arrays but i'll keep that in mind.

I can't switch because then it's not adaptive anymore. I changed the camera perspective and this seems to help. Now I'm peaking at 400M

Want to add that this seems to be a factor for me, still. When trying to get a low angle shot of a plane with adaptive subsurface, the render gets stuck at "Computing displacement plane" with high amounts of memory usage. I have 32GB of RAM and still it doesn't help

Got it. I was having the same problem but now it's fixed. Here's how to do it. As you said,it looked fine in viewport, i.e. with 8px size of dicing scale. So, increase the dicing scale to 8 which will make the dicing scale in render 8px in size instead of 1px which it's doing now. After that,you can render it without problem


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Interior scene has a lot of noise, even with optimized settings

I can't figure out why my scene is still so noise after I optimized the scene / lighting settings.
I have the following settings:
1. Sampling:

I increased the Sample size to 2056
I'm clamping direct and indirect light at value 7.0

2. Lightpath:

Caustics are on.
I use the preset Full Global Illumination
Lowering the diffuse does not help the gain in the render.

3. Portals & Area Lights:

The windows have Portals on them.
Each Portal also have an area lamp on them with a strength of 25 to create some more light.
Multiple Importance is enabled.

4. Sunlamp:

The scene has an Sunlamp with a strenght of 250.
Multiple Importance is enabled.

5. World Settings:

I have set the max bounces to 0. as suggested in this answer ( More noise with Light-portals )

*Note: I don't use the denoiser because I'm rendering on a render farm that splits the render in parts. So the denoiser does not work. *
Update:
Turning off caustics did not improve the render.
Question is: Can I reduce the noise in other ways then increase the sample size?

I was under the impression that caustics can ADD noise, I would try turning them off.

maybe try using this glass set up for your window. https://blender.stackexchange.com/questions/107018/which-glass-shader-is-physically-correct that way the lights doesnt have to fight with the glass.

@icYou520 I can try, but I think they cause Fireflies not the noise right? At least that is what I remembered.. There is no glas in the window.

hmmm, thats true, I just almost always turn caustics off because Cycles can't do them anyway so it just adds to render time and it always seems to give me ugly results. The only other thing I can suggest is up the render samples to 3000 or so.

moar samples! On your local machine select an area, set the Border render and just keep upping your samples until you get the result you want then untick Boarder and upload it to your render farm.

@rob thanks for your comment. I increased the sample size already but still have noise. ( I'm on 8192 now and the darker area's still have noise ).

there are a lot ideas here https://blender.stackexchange.com/questions/68891/what-amount-of-samples-to-use (I like the last answer) but remember every scene is different

The "correct" way to reduce noise is to increase the sample size. You mentioned that this didn't completely solve the problem, but I would use the largest sample size you can reasonably afford (within your time constraints, patience, etc.). Also, I've heard that it's best to use powers of 2 for sample sizes. So maybe try 2048 instead of 2056...
Additionally, the latest versions of Blender have the denoise feature, which works better than an external noise reducer, because it has access to data not present in the final image. It will further reduce the noise in your image.

Regarding portals:

They work best when most of the light in your scene comes indirectly from the environment through small windows. If your scene has large windows, uses many lamps or contains lots of complex materials, portals might actually slow the render down and introduce more noise.

(https://www.blenderguru.com/tutorials/using-portals-accelerate-render-times)
It seems that your windows could qualify as large (though you don't seem to have extremely complex materials), so maybe try a render without portals, and comparing the two in terms of noise and render time. I don't know which way will work best for your scene.

Finally, you could cheat and make the blinds in the windows invisible to all rays except camera rays (the opposite to this answer). This will make the result less physically accurate, but it will let in more light, and reduce the number of bounces light needs to get inside, resulting in a brighter and less noisy picture.


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Same distance betweet multiple objects
I was wondering if there is an easy way to create a gap between objects.

In this scenario I have 4 different objects so an array modifier will not work. But I want to create a gap between then that has an exact amount for all the gaps.
Now I can eyeball it, I can wiggle with the Location properties or I can create a spacer object and use the snap tool to do it. All of these workflows feel a bit extra and will not work on larger scenes.
Is there a easier way to accomplish this?

If you duplicate the original object using shift d and then move it to your desired location, you can then use shift r to repeat the duplication as many times as you desire.

It are different objects though, else the array modifier would be the best way to accomplice it.

assuming that you want to create a vertical gap between objects, and their origins are in the center of geometry, you can use this script to do it, it aligns the objects and creates a vertical gab between them:
import bpy
#Change gab
gab = 1
objs = bpy.context.selected_objects
box = []
for i in range(len(objs)):
    objs[i].location = (0,0,0)
    box.append(objs[i].dimensions[2])
    if (i == 0):
        box[0] = box[0]/2
    else:
        objs[i].location[2] = (sum(box[:i])+objs[i].dimensions[2]/2)+gab*i

Works like a charm!


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How to select a parented hierachy from the 3d viewport using the right click menu?
I know that this can be done in a few other ways too, but I want to know if it can be done from the right-click select menu
As the title suggests, I want to know if there's a shortcut to selecting a hierarchy from the 3D Viewport itself. For example, I have a few objects parented to an object I want them to follow. Now, I want to duplicate or copy all the objects parented to the parent object including the parent object itself. It's rather tedious to go to the outliner and then do the stuff, so is it possible to just select them from just right-clicking on the parent object in the 3D Viewport? I mean we can just do it by pressing Shift + G or from the search menu or whatever, but is it possible in some way to add it to the right-click menu in Blender?

Select children from parent

bl_info = {
    "name": "My Addon",
    "author": "X Y",
    "version": (0, 1),
    "blender": (2, 80, 0),
    "location": "View3D",
    "description": "select and select children",
    "category": "Object",
}

import bpy
from bpy.types import Menu

class MY_OP(bpy.types.Operator):
    bl_idname = "view3d.select_and_grouped"
    bl_label = "Operator select and grouped"

    def execute(self, context):
        bpy.ops.view3d.select('INVOKE_DEFAULT')
        bpy.ops.object.select_grouped(extend = True)
        return {'FINISHED'}

def menu_func(self, context):
    self.layout.operator("view3d.select_and_grouped", text="Select Child")

def register():
    bpy.utils.register_class(MY_OP)
    bpy.types.VIEW3D_MT_object_context_menu.append(menu_func)

def unregister():
    bpy.utils.unregister_class(MY_OP)
    bpy.types.VIEW3D_MT_object_context_menu.remove(menu_func)

if __name__ == "__main__":
    register()

Reference: How to duplicate parented objects as one object

Thanks for the answer!


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Rigging Sphere with Hair to a cylinder with bones
I'm having no luck parenting the below picture.

I have a sphere on top with hair (in orange) I have a arm with bones/armature. I'm able to parent the bones but I'm unable to connect the sphere with hair. Basically I want the sphere with hair to be locked to the arm and have the arm use the bones.
Any assistance would be appreciated. thank you!

Ok, i figured it out..
You need to follow the instructions on this video starting at 20 seconds in: https://www.youtube.com/watch?v=o5f18T7Rjmc
Basically you need to in object mode select the sphere with hair, then select the armature. Go to Post mode and select the bone you want the sphere hair to connect to. cntrl-p select bone.
done.


text:
How To Change Camera Field Of View From Python Script
I'm trying to change the camera FOV by script. I've already seen different questions like this, but the answers doesn't work for me... This is my code:
import bpy
import math

a = 'hello'
bpy.ops.object.camera_add(enter_editmode=False, align='VIEW', location=(50,0,0), rotation=(1.57057,0.00174533,1.57057))
bpy.data.objects["Camera"].name = a
bpy.data.cameras[a].lens_unit = 'FOV'
bpy.data.cameras[a].angle= math.radians(10)

bpy.data.cameras gives access to the camera data. And camera data is not renamed (stays 'camera.xxx') when you set the object name.
So, access the camera via objects and use its data:
import bpy
import math

a = 'hello'
bpy.ops.object.camera_add(enter_editmode=False, align='VIEW', location=(50,0,0), rotation=(1.57057,0.00174533,1.57057))
bpy.data.objects["Camera"].name = a
bpy.data.objects[a].data.lens_unit = 'FOV' #Access it by its object name
bpy.data.objects[a].data.angle= math.radians(10)

Additionally, you should not rely on the fact the created object is named "Camera" (because it won't if such a camera already exists).
You can:
import bpy
import math
from mathutils import Euler

a = 'hello'
camera_data = bpy.data.cameras.new(a)
camera = bpy.data.objects.new(a, camera_data)
bpy.context.collection.objects.link(camera)
camera.location = (50,0,0)
camera.rotation_euler = Euler((1.57057,0.00174533,1.57057))
camera.data.lens_unit = 'FOV'
camera.data.angle = math.radians(10)


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Wondering if there is a hotkey/group mechanism to quickly select a subset of bones from an armature
I've been learning rigging and animating etc and often find myself repeatedly selecting the same collection of bones, eg the 4 feet control bones and spine root bone for keyframing a walking animation. At the moment I am manually selecting the bones every keyframe,I was wondering if there was a quick way selecting them all with one/two clicks.
I have tried to use Bone Groups as described in the manual but right click -> selecting them in the outliner does not select anything. I added them by selecting bones in pose mode CTRL+G for bone group menu -> Assign to New Group, and a bone group dutifully appeared in the outliner.
Let me know if a .blend or screenshots would help illustrate the problem, and thanks for any assistance! (Perhaps it is of note I am running 2.8 under Ubuntu 22.04)

Hi and welcome :)  images are always useful, you can upload blend files with Blend-Exchange as well.

If you select one of the bones and then ShiftG > Group, you'll select the whole bone group.

Brilliant thanks, that's exactly what I was after


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How do I show separation and clear diamonds?
So I've been having a lot of trouble with this project. I want to make a diamond pile falling animation but the diamonds are pixelated and when I render a frame of the animation it is not that clear that they're diamonds.
I use the NLM denoiser (because it seems to be better than OptiX)
I already tried increasing my resolution from 1080p to 1440p (doesn't seem to do much)
I use 512 samples per pixel
32 light paths

It seems like I am missing some totally obvious settings. Any help is appreciated, thanks!

try disabling denoiser. the image has too "random" noise for the denoiser to make the image clear.

I’d say one of the things about diamonds that isn’t showing up here is how bright the refracted light is, and how often it’s a different color. Are you sure your varying the refraction indexes of the colors enough? Why do you add in a white shader afterwards? If that is all correct, I might add a glare node to the compositor.

I think you're getting a pretty realistic result, looking at reference it's pretty hard to pick out edges.  More glossy bounces!  It is usually internal glossy bounces that hit the limit and come back as pure black.


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Doubling objects only when rendering
I have some glass panes on a temple. In all viewports, including render preview, they are the correct amount. Though when I actually render it, the glass panes triple. Any ideas why this it? Thanks for the help

hmmm, do you have an array modifier that's disabled in viewport but enabled in render per chance?

I spent hours on this, and that fixed it. I'm dumb. Thank you so so much wilks!!!!!


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Denoising created weird glowing artifacts on character
Whenever I try to render an image with my girl character, a weird glare is created at the end, when it denoises. Any idea why?
Thanks

I think this is not denoising, but something in the compositor, since compositing also happens at the end of rendering. Did you check that?

Did you disable Denoising to secure it is caused by that? Could you post a screenshot from the Compositor?

...the only way I could imagine this is caused by denoising would be that there is something very bright causing fireflies and the denoiser blurs them all somehow instead of extinguishing them. But that's also something you can check better if you disable Denoising.


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Texture Painting Help
I do have a basic scene (demonstration)
Texture painted sphere (red color based and white plus (+) on it.
The thing i want to achieve is keep that white part (kinda lock it) and change that red part with nodes whenever i need it.
Thanks in advance.

I would convert the texture to its green channel as a file, but if you need to keep it red, you can do it nodewise with the Separate RGB node, then use the green output. In either case, use the result as the factor of a Mix RGB node to mix between whatever color you want (color 1) for the rest of the ball, and white (color 2) for the plus sign.


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Colouring a particle system based on the emitter (Blender 3.1.2)
I am quite new to blender but i have to get a task done and i am learning a ton of stuff as i go. So here is my problem:
i want to have a particle system on a plane thats devided x times on the Y and X axes so i can set it up in a non chaotic grid. To achive this I emit the particles from the vertices and render them as instance objects that are based on a uv sphere. the result is much to my liking but now I have to colorize it with stripes on certain areas.
I have tried to set up colorramps and shaders to control the color and the area thats effected. But I can use this setup just in a certain area of my particle system maybe just in half of it. the colorramp also doesn't work linear but more or les logarythmic. When I shift arround a second particle system with the same setup and material, the stripes kinda have some depency on the XY axes too. BTW I am working with Cycles.
Sadly I can`t provide any open files, but i can provide you a picture of my material set up.
So in total is there any way i can achive my desired effect of having a grid like particle system that is colored differntly in certain areas?
I Would be very happy if some one could help me out

Similar questions: 1) https://blender.stackexchange.com/questions/166840/blender-2-8x-particle-color-based-on-actual-color-of-emitter -- 2) https://blender.stackexchange.com/questions/203035/how-to-add-a-texture-to-the-emitter-surface-of-a-hair-particle-object-over-ridi

Thanks Blunder, but this solution might not work for me, I saw this post previously and in this example they are emitting the particles from the faces of the plane not the vertices. if you change this blender example to "emit from vertices" all particles turn to the color of the instants object. But I need to emit them from the vertices to achieve a nearly perfect grid effect

there is also the exact same question but the links provided as answers are not working anymore https://blender.stackexchange.com/questions/66929/inherit-color-on-hair-particles-emitted-from-vertices-cycles

With Geometry Nodes (GN), you can map the (face) colors of an image texture to vertex colors. Unfortunately, it seems not to work with the particle system (Blender 3.1). But you can also instance objects with GN. The drawback is that you need to realize the instances to color them. This can result in a lot of geometry in the viewport.

Hello Blunder, unfortunally I cant't realize the instances, because it would slow down my computer to the extend that i could not work with this blend anymore, but i guess this would be the right solution for some simpler geometry. Thanks a lot, I am going to try it out!

Q: How to colorise particles by emitter's texture when emitted from Vertices?
Don't use UV but Generated coordinates with From Instancer enabled.

Hello vklidu, actually this did the trick!!! thanks a lot! Now I can paint the desired design with texture paint and thats pretty cool!
Right now I try to make it work with the gradient texture too. So far the instances show the texture of the instance object :/ Same setup just switching from image texture to gradient texture + ColorRamp and I am stuck again.
But thank you so far!

If the answer solved your issue consider mark answer as accepted. https://blender.stackexchange.com/tour if you have another issue that wasn't asked already on this site don't hesitate to ask a new Q. Good luck with your project (•‿•)


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Extruding face without leaving gap / hole behind
Is it possible to extrude a face without leaving a hole / gap behind?  See animation below.  I would like it to remain a closed / filled face.

I'm trying to avoid having to go back and fill in all the holes I may need to create after extruding.

Hi :). Just keep in mind this would lead to non-manifold geometry. Unless that's what you want.

No, I don't want that is there another way I should be doing this?

inset to value one with 'i', then extrude. I'm surprised though that it does what you show

@Yvain doing a inset with a value of 1 just makes the face smaller, and the hole is still there just smaller.

Did you try it ? Inset at zero maybe to keep the same size and then extrude, you should keep your bottom... don't forget to recalculate normals after

@Yvain yes I tried 1 and 0 as inset values, it still creates a hole when extruding.  Didn't recalculate normals since the hole is still there.

that's the way it works, if you want to avoid the hole you need to give thickness to your faces underneath, or you can still fill the hole but this is bad topology

That's the way extrusion works when there's another face next to the one you extrude:

You can still fill the face but it's not a good topology to have more that 2 faces connected to an edge:

To have a good topology give thickness to your bottom faces:


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How to find / search where a node is in geometry nodes tree
How to find / search where a node is in geometry nodes tree.
I have a large node tree and would like to be able search / find specific nodes like set material nodes, is there a search or key combination to search for a node in a node tree that will take you to a specified node?

Just use CtrlF and type the name of the node you're looking for.


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Boolean glitch on object - Creates duplicate rather than subtracts
I have a cube (on the right side of image) I wanted to slice out an oval from. No matter how I try it will NOT subtract. It actually creates a duplicate object (that what I wanted sliced) and JOINS that duplicate to the object it should have been sliced from. Annoying! So I created the same objects all over again and it worked just fine as you can see with the rectangular object on the left. So NBD. I just want some resolution as to WHY it won't work on the first dang object. Try it yourself. Blend file attached. (disregard the image behind the cube on the right side)

You may want to see ..... http://blender.stackexchange.com/questions/44144/boolean-modifiers-are-not-working-correctly-on-this-mesh/44151#44151

You may find it helpful to you and others .... to delete the ancient file and replace it.  The incomplete boolean modifer dominates the discussion.

What ancient file The blend file or the picture?

People might open your blend file and look at settings that you say you have changed and corrected.  Do you want that?  Rhetorical Question.  But it would be a better use of our time to move onto new questions and ideas.

Image revised and new blend file added (however I did not hit apply in this document, so that anyone wanting to test it can duplicate the same issue and cleraly see ---IT DOES NOT work.

Possible duplicate of Booleans are all messed up plus http://blender.stackexchange.com/questions/27675/boolean-difference-removes-wrong-part?rq=1 (in your case apply scale& rotation to the rectangle and recalculate normals)

As you stated I applied scale & rotation to the rectangle. And tried the operation again. It did the same thing. Again. I do not know what "recalculate normals" means or how to do that. But the answer right below stating "my normals looks okay" and "change the Y scale from -0.5 to 0.5 WORKED.

If you switch to Union it will do the Difference and vice versa that's even though the normals look okay the object in fact is inverted on the Y axis look at the scale on the Y it reads -0.5 just change it to 0.5 and it will work as intended

EXACTLY! You nailed it! Such a simple thing it seems... Good catch. But now I'm not understanding how or why changing the Y axis on the scale from -0.5 to 0.5 effects this. What's a "normals" (that "look ok")?

@Marc normals are direction where the face is pointing ( facing ) , they should point outside the object, when you do boolean operation what is behind the faces is considered the inside , apparently the scale is taking in consideration so a negative scale means the the object was flipped inside out

You need to specify an object in the modifier.

The red color above indicates the object is incomplete.
You likely meant to do something like this below

Sorry. Yes.. I know I need to specifiy an object. I DID. Problem IS (and the reson why I provdided the blend file) is that even after specifying the object, hitting apply -- I got the results as described above. IT WILL NOT subtract. And yuet the very next test (on the left) it works fine.

You may find it helpful to delete the ancient file and replace it.


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How to scale proportionally

I'm extruding the faces selected on the screenshot.
With the selection active I press Alt+E (region vertex normal). the result that I'm getting is shown in the animaiton above. The extrude isn't done proportionally at the sides and height or z-axis.
May I know the reason what I'm doing wrong and how to make it extrude all the sides proportionally?

This happens because you haven't applied scale , so to apply scale ,press space bar search for Apply Object Transform , click the option then go at the tool-bar then under the tool-shelf and select scale.
then repeat the steps you are doing in your question.
Note: you should be in object mode to be able to search for Apply Object Transform.

thats perfect..

If I understand correctly what you want to do, then you just need to extrude then confirm the operation immediately before beginning any transform.
E then Enter or LMB and then you can use Alt+S to scale along the normals.

thanks for replying u have understood my question correctly and showing correct what i need. but when im doing the same as u have done the question come same its not proportionally scaling whats the reason i dont understand plz do reply


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Getting Horrible spots on textures

I cant simply paint on certain surfaces and i am getting some weird spots on the surfaces that i can paint. Does anyone have a fix???

Please only ask one question at a time. You've already asked a question about not being able to paint on the whole model. I suggest using the [edit] link below your question to edit your question so that you are only asking about the spots.

Don't add any words indicating that the question is solved into the title; marking question as answered already did this

ok i will remove it. sorry for being such a headache

You need to look at zooming in closer to your paint surface, or maybe switch to the Fill tool since you are using Face Select Masking it might be easier to drop the color in that way.
The main reason is that 3d painting uses projection, and being far from the target can cause it miss. Smaller brush sometimes helps also.


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Can Blender process an image on a webserver?
Does any one know how to achieve the following...
I'd like people to be able to submit a .jpg image via a web page. Once the image has been submitted I'd like blender to texture an object using the submitted .jpg image. And then I'd like the final render to be emailed back the the person who submitted the .jpg image.
Is this possible?

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

Can you be more specific about what part of the process (within blender) you are interested in? As it stands, the linked question is most likely a dupe, but if the command line part is not what you are having trouble with, then could you please elaborate?

Hi. I'm wondering if Blender can be used on a webserver to enable people to submit an image, which is then used to texture an object. The resultant image is then emailed back the submitter.

Hello, I'm hoping for some progress on my question. Does anyone know if it's possible?

So essentially you want to use Blender as web service with it running elsewhere while all data to input is fed via remote computer (not only rendering). There isn't any built-in way to do it afaik and while there were some addons being created a while ago they weren't finished from what it seems. While you can write your own  addon for that like in controling Blender via browser it requires quite a bit of coding and Blender knowledge


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Blender cycles rendering layer but keep to sum memory?
something i really don't understand!
i made different layer for my render.
i have 5 layers, i set for everyone: layer to render, layer to exclude and eventualy also the mask layer.
if i render from composer editor every single node (clicking in render button in render layer node) i don't have problems!
when i start the render (f12) i have render out memory problems on last renderlayer!
every renderlayer work good but in rendering information i see the memory usage sum to previous renderlayer
example: when renderlayer1 finish mem = 100, when renderlayer2 start mem = 101, when finish mem = 200, when renderlayer3 start mem = 201!!!
in this way my GPU memory go full before finish the rendering!!!
N.B.: the last render layer is rendering just 1 layer, excluding all objects layers (keeping just layer for commons light) and have no mask layer active. if i render just this render layer i give to me 991M Mem usage. when i render this from f12 render i give me out memory over 3200M mem usage!!
i can set something for clear memory every render layer?

the only one thing i can do it's export every single layer in different file and compose again later...
but is a very stressfull way

This look like bug and all what you can do is report as bug with most accurate info as you can.
I noticed that Blender have problem with VRAM freeing sometimes. Try save every render layer separately. I recommend use multilayered .exr for keep render passes. Now you can composite everything in new .blend file. Optionally you can use other compositor like Natron or Fuse.
Last time I always use this workflow for more complicated projects. This method give me possibility easily rerender only layers I need later and without rendering everything again.
I don't thing this is "stressfull way", ultimately this can save you a lot of time. Only you must link your images smartly and work will go fast :-)

i did a multilayer file output. if i link all render layer and i start the rendering i still have the same problem!
so the only one way it's to deselect last render layer. export alle the others in multilayer file and after just export last one in separate file.
and compose everything

Yes, that's the reason why you need save layers to .exr. You need close blender (for free VRAM) and open it again for render last layer. Also you can set render to CPU for last layer and check how many RAM this layer actually need. Only for info.

Maybe you can move last layer to first position and render everything at once.

i checked the last one memory it's around 800 Mb.
all the other are a total (summed by blender) of 2900 Mb so for my 3Gb card it's impossible to compute.

i think i used so much memory because i made a lot of render layer for use different quality of rendering... i have the wall (not so much quality), the object in the room (they are also computed by the wall for mask and shadow) and i have main object (high quality) and a fur object (high quality, my last layer) also i have 2 low quality render layer for particles.. so the problem is i use two time room elements (one for wall and another for object) but it have not to be a problem if every render layer blender refresh memory

@Piedecess I suppose you thing 2900MB, not 2900Mb. Be careful, this is not the same. And for more confusion 2900MB is not the same as 2900MiB :D

yes! you're right!! keyboard issue ;)

consider upload .blend with packed all data for check setup. Please use this:  http://blend-exchange.giantcowfilms.com/

What could happen is that while you are rendering on the GPU, all framebuffers need to be present on the GPU until they are flushed. At least this would explain the behaviour you see. Blender will output the buffers once all checked RenderLayers are finished, that includes the Compositor. When you manually click the Camera icon, only one renderlayer is sent to the GPU for rendering, after that the framebuffer is flushed again.
Maybe you can get the scene to render successfully again if you try to save the tiles to your hard drive locally while the rendering is running. Check the Save Buffers option and give it a shot:

Very likely this will slow down your render times, as every time a tile is finished, it needs to be written to your tmp directory, but at least it could stop the crashing.

also with Save buffers option it still to give me memory error


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How do I fill a texture with another texture?
I created a small tileable texture in blender. Now I need to fill a larger texture with the small texture.

I need to use the above texture on a large plane so it tiles.(like tiles) But when I use the fill brush it only fills a color, not the texture. How do I solve this?
Sorry if the question is not clear. Thanks in advance.

Judging from your question it looks to me as if you're trying to texture paint a repeating pattern onto another mesh. This is indeed possible, but not using the Fill Brush. You'll need to choose the Draw Brush for this instead. See this little example for the settings:

When setting the Brush Mapping to Stencil, you will see an Overlay plane in the 3D Viewport as soon as you put the mouse cursor there. The Size parameter allows you to set a custom number of repeats for the texture itself. The result could look somewhat like this (Plane and Overlay visible at the same time):

Easiest way how to blend textures is mix them together using "Colors" -> "MixRGB"  node in node editor:

Second option is use external image editor Like GIMP, Krita, Photoshop etc.
For fast and easy workflow you can set path to your image editor in
"File: -> "User Preferences" -> "File" -> "Image editor"
Now you can send your texture to your external image editor from Blender UV/Image editor by
"Image" -> "Edit externaly".
If you finish editing in external Image editor, just overwrite original image and In Blender Image Editor use
"ALT+R" for reload your edited image.

Thanks, but it didn't help my problem. I want the large texture to contain many of the small texture. Like Tiles. Repeating to make a bigger texture.

In this case, look at mapping node - here you can set "scale" - For example scale 2 will repeat your texture 2 times. Or you can make UV coordinates bigger in UV/Image editor.

BTW: Your question is: "How do I fill a texture with another texture". I'ts misleading


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How to render All layers in my Compositor at once
I have a node grid that renders and adds 10 different layers together. I have added a composition node in the end of the node grid. Though when i Render (F12) it seems like only one of the layers in the composition is rerendered and the other nodes are just applied without rerendering. How can I make all nodes rerender when hitting Render(F12)?
Sorry if my question is unclear, I am a Blender beginner so find it hard to explain my problem.
Any help appreciated! Thanks! :)

Currently I have to press each "green-render-button" (marked in image) to finally get the complete result. I would like to be able to just press Render (marked in orange) and have them all rendered into final image.
Obviously there is something I don't understand because I can't make sense out of it...

Could you upload a .blend file that showcases the issue? What are you trying to achieve? If you can't upload a .blend file, try attaching screenshots to your answer, you can upload the .blend file here: http://blend-exchange.giantcowfilms.com/

In addition to the nodes, please also give us a picture of your render layers setup in the properties window.

I have now tried adding more relevant information. I can add more information if needed. I can not upload the blender file though, because my work is for school and uploading it can cause troubles...

One more important thing to show is setup of the render layers settings located in the Properties Editor. It could happen that you checked only one layer to be re-rendered (the selected one); it's a small icon to the right from the render layers list.

@MrZak added an image of the Render layer list.

You selected Only render the active layer option in the Render layers list.

With this option only currently selected render layer (active one) will be rendered while others won't be; thus while compositing you'll see new results only on this active render layer.
From manual:

Using Render Layers can save you from having to re-render your entire image each time you change something, allowing you to instead re-render only the layer(s) that you need.

Deactivate this option and all the Render layers will be rendered again when you press F12 (or with any other way).

Great you solved my issue! Thanks! All buttons in Blender can be quite overwhelming and confusing for a noob like me ;)


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My Blender display is cut in two

No matter what my display settings are, the main Blender screen is split in two and the two halves are displayed back to back. In other words ][ instead of []. Help!
No, these are not two separate view windows. It is one view window cut in half.

Possible duplicate of How to close view windows?

@Timaroberts Maybe, but it's strange that the right half would fit exactly on the left half of the screen. Maybe it's rather a display driver issue? user35648 Could you provide this Blend file? Just save it somewhere and upload that to http://blend-exchange.giantcowfilms.com/ for investigation. If it is a UI split thing, that should be easy to replicate.

imho there's something strange here, there shouldn' t be that black gap, never... could it be a graphic driver issue with blender's opengl drawing? Does this happen with past blender versions, and with any file? which kind of device is this?

Have you tried the following: restart blender, restart computer, uninstall --> reinstall blender, install older/newer version of blender?

I am attempting to run Blender 2.77 on an ASUS A555DG (AMD) laptop running Windows 7 Pro. Installing another Blender version would probably be time-consuming and would not be my first choice. A sticker affixed to the laptop says "Radeon R8 M3500DX 2GB." Device Manager says there are 2 graphics drivers, "AMD R5 M330" and "AMD Radeon R7 Graphics." The version number for each of these drivers is 16.300.2311.0, 7/18/16. I'm a total Blender noob and have no idea what a Blend file is or how to obtain one.

Hold the presses: there's an AMD driver hotfix released 9/21/16. I will attempt.

Tried updating display drivers. Tried loading 2.78. Tried running as admin. At Blender startup I get a message, Failed to load 44100 Hz something something 48000 Hz (the message comes and goes too fast). Same problem.

That message Failed to set 48000hz shows up a lot, I get that too I think, it has nothing to do with your problem.


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Select random by loose parts
I have the following mesh. It is a series of hexagons placed on a plane.
I'm trying to select random hexagons to give them another material. I know there is a select random function, but that only works on vertex, edges and faces. I'm trying to do it by loose parts.
Is there an option to do this?

Bmesh Script
Using the script from here (which happened to come up today re another q) that finds all loose parts in a mesh.
Test script, run in edit mode on a mesh. Selects a random loose part on each run.
import bpy
import bmesh
from random import randint

def walk_island(vert):
    ''' walk all un-tagged linked verts '''
    vert.tag = True
    yield(vert)
    linked_verts = [e.other_vert(vert) for e in vert.link_edges
            if not e.other_vert(vert).tag]

    for v in linked_verts:
        if v.tag:
            continue
        yield from walk_island(v)

def get_islands(bm, verts=[]):
    def tag(verts, switch):
        for v in verts:
            v.tag = switch
    tag(bm.verts, True)
    tag(verts, False)
    ret = {"islands" : []}
    verts = set(verts)
    while verts:
        v = verts.pop()
        verts.add(v)
        island = set(walk_island(v))
        ret["islands"].append(list(island))
        tag(island, False) # remove tag = True
        verts -= island
    return ret

#test code
context = bpy.context
ob = context.edit_object
me = ob.data
bm = bmesh.from_edit_mesh(me)

islands = [island for island in get_islands(bm, verts=bm.verts)["islands"]]
if len(islands):
    #deselect all
    for v in bm.verts:
        v.select = False
    bm.select_flush(False)
    for v in islands[randint(0, len(islands) - 1)]:
        v.select = True
    bm.select_flush(True)
bmesh.update_edit_mesh(me)

Possibly more useful, re a scripting solution,  would be to randomly assign materials from a list to loose parts.

Here the single mesh array of suzannes  has 6 materials, which are assigned to each loose part randomly.
#test code
context = bpy.context
ob = context.object
me = ob.data
bm = bmesh.new()
bm.from_mesh(me)

islands = [island for island in get_islands(bm, verts=bm.verts)["islands"]]
for island in islands:
    #deselect all
    for v in bm.verts:
        v.select = False
    bm.select_flush(False)
    for v in island:
        v.select = True
    bm.select_flush(True)
    mat_index = randint(0, len(me.materials) - 1)
    for f in bm.faces:
        if f.select:
            f.material_index = mat_index
bm.to_mesh(me)
me.update()

This is even better!

To select hexagons randomly as in your case, you must use the random function with vertex, edges or faces.
Then simply press " CTRL and  L " as mentioned Duarte.
Or press several times  " CTRL and  Numpad  + "  to add all part of the hexagons.

Ctrl + L Select Linked operator would probably be more adequate here


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Giant Pixels on Rendering
So I made a small scene, when I click the render button this is what I get:

Now that's not how its supposed to render I didn't make large pixels.
This is how its supposed to turn out:

Plus while rendering I'm getting the transparent image texture in the Camera, I've added a new camera with all the default settings and its still the same.
Kindly let me know if you guys have a solution.

Can you show us the Camera properties tab?

The percentage entered below the render resolution is a factor that allows you to quickly decrease the output resolution, e.g. to render a smaller preview.

You accidentally set this setting to one percent which means the final image has a resolution of 19 by 10 pixels instead of 1920 by 1080.

Thank you so much that solved it :), funny I didnt notice that :P


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Getting the width of a group node
I know we can change the node width in Blender 4.3 but how can we find out what a group node width is when we stretch it out (It says 140 but that's just the default not the current changed width of the selected group node)?  See image below.

Select the node (so it is active), ⬆ ShiftF4, then paste into the console:
C.area.type='NODE_EDITOR';C.area.ui_type='GeometryNodeTree';C.window_manager.clipboard=str(C.active_node.width)

↩ Enter and now you have the width in your clipboard.

Thanks, looks like they may want to add a simple info box that shows this

@Still You can try to request that, but I don't know if there is a huge demand for that. After all the important thing is what the nodes produce, not which size they have in the editor. Anyway, a place for feature requests like this might be here: Right-Click Select Blender Community

@GordonBrinkmann I wrote one feature request on the right-click select, and it displayed the post as published, but it was visible to only me (dark ux pattern), and it was never published to anyone else, and without any response why. So I can't recommend this site.

@MarkusvonBroady I never requested any feature, I only know that others have suggested it before on other questions, and since I never needed something like that I have no other recommendations unfortunately.


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import ply file and rander depth map using nodes
I sucessfully import .ply file using add-on. Now I am trying to get depth map using composting nodes. But I found that the imported ply has no Z channel.
So how can I handle it?

You should choose the scene to get data from:


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How to delete the vertices and faces from the transparent parts of an alpha channel?
I have a Body mesh with a UV combined with an image texture which has transparent parts through its alpha channel.
I need to delete or dissolve the vertices and faces of those transparent parts and turn the mesh into a new, clean object.
Made a vertices group of the visible vertices and then used a modifier to dissolve the other vertices. But that won't work all the time because with low res objects visible and transparent vertices overlap, so the result won't match exactly.

Hello could you please show some screenshot?

Please provide screen shots of your current issue so we can better understand your question. You can paste them directly into the post.

I don't understand the last part and what's the problem. With Geometry Nodes, you can delete vertices based on the transparency mask (https://blender.stackexchange.com/q/264833/107598). Might be helpful

@Moonboots and JakeMoyo. screenshots has nothing to do with it I just need some vertices deleted when there transparent.

@Blunder Thanks


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modifying vertices of an imported obj object
[![What I'm trying to do here is to create distinction lines just like in cars. I modeled it in Fusion360 and imported it to Blender as obj. First I selected those edges that are highlighted as light blue and moved them lower to create a gap between the other surface. Then, I extruded the edges towards the inside(so it's not visible from this angle). I did that to create a bevel, but it won't do anything. I'm suspecting that the edges(highlighted light blue) somehow have a problem because normally edges are white when selected. What could be a possible issue that I can solve? THANKS! ][1]][1]
What I'm trying to do here is to create distinction lines just like in cars. I modeled it in Fusion360 and imported it to Blender as obj. First I selected those edges that are highlighted as light blue and moved them lower to create a gap between the other surface. Then, I extruded the edges towards the inside(so it's not visible from this angle). I did that to create a bevel, but it won't do anything. I'm suspecting that the edges(highlighted light blue) somehow have a problem because normally edges are white when selected. What could be a possible issue that I can solve? THANKS!
[1]: https://i.sstatic.net/zdlA1.jpg

https://blender.stackexchange.com/questions/40292/what-are-the-light-blue-lines-on-my-imported-objects?rq=1 for the blue lines.


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Added material - now it's covering several parts of my model, how do I stop that happening?
Applied texture to one object, added nodes, came out nice, however the photo/texture from that object is also on several other parts of my model, and I don't know how I have achieved that.
Perhaps I have the model linked, but being new, I am not sure of the differences yet between linked, joined, or parents and children etc. What have I done wrong and how do I fix it?
I have tried to unlink the model (if that's the problem that's causing the texture to appear over other parts not wanted), by going to object relations, make single user. However, that doesn't seem to have worked.   TIA

You can add multiple material slots to an object and assign different parts to them in edit mode. https://docs.blender.org/manual/en/latest/render/materials/assignment.html

https://blender.stackexchange.com/questions/75816/how-to-distinguish-material-and-material-slot/75820#75820


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File output node outputs wrong image resolution
I have the node setup shown below.
The input image size is 8000px by 4000px. The scale node is supposedly reducing this to 800px by 600px.
If I hit render, and then manually save the output from the UV Image editor, I get exactly what I would expect (a nicely scaled image size 800px by 600px).
However, if I go to look at the file generated by the file output node, I get a different result. I get an image of size 8000px by 4000px with my 800px by 600px shrunk image in the centre of a massive black border.
How can I make the file output node output a properly scaled image?

Can you provide some screenshots of the UV Image editor that show the rightly scaled image and the file output? What's your "canvas size" (I mean the values of Resolution in Render Tab)? Give a look to this related answer: http://blender.stackexchange.com/a/2404/15140

You can try to use Crop node after the scaling

@Carlo This doesn't look like the same issue to me. In this case, the composite node gives the expected result.

Also related: http://blender.stackexchange.com/a/19329/599

@gandalf3 true and that is why I initially dismissed that solution, however, I have tried it again this morning and mixing with a mask node does indeed resolve the issue with the file output. Thank you for your help everyone.


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Cycles - losing renders layers
I am trying to composite two render layers, but compositor is acting a little odd. I unchecked backdrop for a moment and the image completely disappeared from compositor as well as the image editor.
I have also noticed that I had to fiddle with the zoom level for the renders to show up, I'd have to reset zoom levels and still use ALT + V to zoom.
I am using Blender 2.74. Rendering on Phenom(tm)II X4 965 CPU. Any help? Can not afford to rerender.. Thanks for help in advance.

Can you post a blend file that demonstrates the issue?

Happens with multiple files.

Are your 2 render layers saved out to external files, or are they just in blender in the temporary frame buffer? You should save them out to file if you want to avoid re-rendering. Then we can fix the compositing issue after that.

That's what I usually do, just clicked around a minute right before saving in the compositor bc I couldn't see the renders and for a minute it seemed like if I unchecked backdrop and checked it again might have fixed it. But instead in composting view it only deleted it from image editor slot, after which I just lost it completely.

If you have to render it again, render it out to a multilayer exr file without the compositor. Then you can composite from the exr file and make sure you don't lose your render again.

This sounds great, accept I am a little unclear on what you mean by "without the compositor, does that mean I can or should somehow exclude the compositor? I am not even sure of what that might mean. Correct me if I am wrong but I think you are just suggestions to save a file AFTER re-rendering. That gets us back to my issue of not wanting to take one more day to render. But thanks for your input. Is there a temp file for the renders or anything like for Maya where if u save it in buffer it's temporarily stored on your computer? bc if there is I can not find it.


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Emission Light Problem
By adding an emission light behind the bottles, in front of the back drop I cleared up the issues with the black bottles as mentioned here: Clear "glass" bottle loses clearness in front of colored background
However by doing so it created a new issue when that same corrective light now blocks the image behind it, thus not allowing that image to show through the transparent water bottles.  For clarification the emission light is moved over slightly and shown highlighted in red so you can see that it does reside between the bottles and the backdrop. I need that back drop to show THROUGH the bottles. Ideas? Suggestions? Solutions? Thanks.

I THOUGHT The light was blocking the label behind it from showing through to the bottles in front of it. However it turns out there was actually a duplicate bottle within the bottle that I did not know about, plus the normals of that bottle were apparently backward. Once THAT was deleted it appears everything works fine. Arrrgh. Stupid error on my part. APOLOGY.

Select the emission Plane.  Set Cycles Ray Visibility Camera to False.
You may choose to locate the light or lights anywhere convenient.

Please enter your solution or update the original.  I will delete my proposed answer shortly.

I understand what you wrote.  I am just suggesting that you update your question. Create a new  answer and select it if possible. Otherwise put you answer in the original question itself.  So no one else tries to answer.  New title to question can be ... Emission Light Problem [Solved]


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Lattice object / modifier will not bend
I added the Lattice object and modifier to a square tube object, went into edit mode, 'B' selected the nodes I wanted to try bending.. pulled them out.. and. Nothing.

Does the object which should be bent has enough loopcuts so to be bent ? And is lattice itself selected in Lattice modifier added for object to be bent ?

Yes. I think I already did that as you described. Here is the blend file:

I edited your question to add the link to the blend which was broken. Feel free to make changes further on if this .blend is not yours.

To get your Lattice deformation to work:

First of all you have to subdivide a mesh at least with several loopcuts (and the more smooth transitions you want, the more subdivisions you need). To be concrete, exactly this wasn't done for your mesh in the file.
Then add a Lattice Modifier to your mesh, then select created lattice in the "Object" input box of the modifier.

Only after this is done, will modifications to the Lattice affect the mesh.

EDIT:
Alright, after taking a look a the blendfile, the reason for the modifier's misbehavior became clear: you simply don't have any subdivisions in your mesh, so it cannot bend. The lattice modifier affects existing geometry, and can only move existing vertices. As you can see in the gif below, after I added some subdivisions to the length of your mesh, using the Loop Cut and Slide Tool (CtrlR), the Lattice works fine.

Yes. I think I already did that as you described.  Here is the blend file:

I edited your answer to include only one extra step needed which wasn't done by OP. Other than that all the details are already added imo.

Alright, problem found using your blendfile, @Marc. See edited answer above.

Cool, thanks @MrZak (only saw this after my own edit, but still improves the original answer)


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Modeling with Knife, Loop Cut and Inset
The result of using Bevel and then Inset I should be as seen outlined in red.
However when I click I it will does not do anything of the sort.

Suggestions?

You are in edge select mode.  Try it with faces selected.

After pressing I (I like independence) to inset faces hold the Ctrl button (and move the cursor upwards) to add some depth to the faces and achieve the result you want.

They don't tell you that in the tutorial! Thanks!


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How do I add polygons to fill a face?
trying to recreate this Elijah bottle. I have two sides, one of which is outlined in red. How do I fill that face with polygons so I can then grab the center (that red square dot) to pull it outward thereby creating the slight outward bowing of the bottle?

Never heard of grid fill until now. But I'll search how to do it  --thanks for the hint / how to.

So I tried Grid fill by selecting 5 vertices on each side, cntrl F, grid fill and I got the message "Loops are not connected by wire/boundary edges" --which I need help translating to layman's terms please... I also tried selecting ALL the edges and still got the smae message


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A tube of light in a volume shader
As I had much fun with this (thx Chebhou) but gaussian functions are a bit too complex for me, i want my volume scatter cylinder to have simply a smaller cylinder emitting light inside it, from the same object/material. The same size all along, or why not being able to control the fading at one or both sides (why not asking :) )
It has to be done with math nodes, vectors and things like that (what I want to learn)
Something like this but in a single object

looks like a light saber :)

@cegaton nope, i don't want a compositing or modeling answer, it has to be shader maths. I already did (long ago) a light saber but i want to learn more about math nodes and vectors in materials. I hope this is simple enough for me to understand the why and how.

use this circle equation and chose a radius "max R = 0.5" :

Coordinates node group :
and for fading on the sides i used a sin function :

render :

seems like what i wanted, checking details :)

the sin doesn't seem to fade the light, it just stops at both ends.

it fades but in short range that it's not clearly visible because that's how a sin wave is, you can replace with other functions

Max R=0.5 :) A max value of 1 would be for diameter.

yeah, you are right

Variation on Chebhou's answer : Origin and dimension independant :

Not sure the sine works exactly the same.

that's brilliant ! it is dimension ,and origin dependent


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How to create glass with a glowing core in blender?
I'm a newbie to Blender and would like to create glass objects (rough glass) with a glow coming from the center. For example, you can think of glowing marbles when the glow source is trapped inside the glass.
What's the best approach for creating such an effect in Blender?
Thanks in advance!
EDIT: Some missing information I forgot to include: I'm using the Cycles engine, and am aiming at a look similar to this image: http://www.supercoolpets.com/pictures/HA6319blueLight_x.jpg (less texturing on the glass itself perhaps though)

Please add a screenshot/image ilustrating what kind of result you want to achieve.


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Human toes rigged not deforming correctly
I rigged up a human foot, using only one bone to control all the toes. When I rotate the bone up or down the toes don't all stay at the same level.

I want them to stay flat, at the same level, like how they are when the bone is not bent up or down.

As you can see, the toes are all weighted the same, yet the are not level when rotated up or down.
Any help is appreciated.
Thanks

Can you show us your weights? Select the mesh, press Ctrl + Tab, then select the bone. The weight assigned to these toe bones should be shown.

@Leander I edited the post for you.

@BlenderGuest could there be some other bone's influence only on the Toe, and not on other fingers, thus making the Toe less influenced by the bone you're posing? the above picture is in perspective mode, though, and not aligned, from the side the difference could be less evident... you could rig single fingers, to get better individual control, too.

To check if there more multiply influences as m.ardito suggested, select a vertice of the big toe and check the "Vertex Weights"  section in the Properties panel in the 3D view. https://blenderartists.org/forum/attachment.php?attachmentid=328682&d=1408770170
Consider uploading your file to http://blend-exchange.giantcowfilms.com/ so we can take a look.

The easyest way to do what you described is probebly to rig each of the tose seprat and fix them separat.
If you rig the tose as one bone they will be deformed as one object and will probebly create a new problem if you fix one.
The deformation is done lineal and you whold need to make a exponetial deformation to make it work. You could cheat and play with the weights and make it god enoth but it will be limeted.

This happens because our toes don't have their origin point in the middle of the foot, they each have their own so if you want them to be more precise but still have just one bone to control then you would need to have one bone for each toe and then have them copy the rotations of this bone you already have to use as a controller. This way each toe has their own origin but you still just worry about moving one bone.
If what you're looking for is optimization then what you could do is add more weight to the smaller toes for the foot bone so that they're not so heavily controlled by the toe bone, they'll still follow it but a little bit less and it'll look better although not as good as if you had a bone for each toe. But that's how optimization works, you have to sacrifice small details.


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Weird problem: Render time increases frame-by-frame
I've encountered a very weird phenomenon which I have trouble with: When I render my scene (using the Cycles engine), the initial render time of the first frame is at around ~2 seconds. However, with each frame that is rendered after that, the render time increases by a few hundredths of seconds, sometimes a tenth of a second. After some time, the render time for a single frame has reached almost 1 minute.
The scene itself is not very complex, save for a (baked) particle system and some drivers (which cannot be the source of the problem, since I've created a version of the scene WITHOUT those objects for test purposes - and the same problem remains).
I'm rendering with version 2.79b on a Lenovo Thinkpad T550, which is sufficient since the scene is - as mentioned - not very complex.
Any help/suggestions would be appreciated!

motion blur can have significant effect on render time on frame-by-frame basis..

Thank you for your response, Jaroslav. The scene does not use motion blur, so the problem must originate somewhere else

Hmm, that was my best bet. Can you share more information about the scene/animation or render settings? The symptoms don't indicate a concrete problem. For example: are the frames the same visually or does geometry coverage of the frame area change?

I won't be able to post the file, but the visual nature of the frames stays very consistent (i.e. no extreme changes in geometry), there are just some elements fading in and out (animated materials). There is a very large amount of transparency bounces though (min: 25, max: 30), but I already tried decreasing those and it did not change anything.
A few months back, another user reported a similiar issue, which was not solved: https://blender.stackexchange.com/questions/105199/successive-frames-take-longer-and-longer-to-render

Could you reverse your timeline and check if this is still the case, if so I think this would prove its not complexity increasing in each frame as one would expect it to decrease in this scenario.

I think I've found the culprit: Through reverse-engineering, removal of geometry and exclusion of certain RenderLayers, I could determine that the increase in render time was caused by Curve objects (Bezier Circles). Once I'd converted those to regular meshes and did a re-render, the problem disappeared.

Can you simplify the scene, and see the persistence of the problem? If so, maybe it's worth posting a minimal version for others to try in different Blender versions, with different hardware, to see whether it should be submitted as a bug report?

A good idea. I'll give it a try

Hey Blender 3.x here with kind of similar Problem and a Bezier Curve for camera motion. Did you filed a bug report?


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UV Unwrapping complex drilled cube
I know that UV unwrapping is a black art, and I am just beginning to dabble in it and try and understand it. Most of the time with the things I need to unwrap either a Project From View or Smart Unwrap suffices. However I have come up against one scenario where neither will work, and all my attempts to manually unwrap have failed.
The object is basically a cube (extruded SVG shape consisting of 4 lines) into which (as you may have gathered from my other questions) lots of holes have been cut through it using a boolean modifier.
On fairly simple ones a smart unwrap works adequately, since I only need to texture the top and bottom surfaces. However when it gets more complex that fails, and you end up with a number of islands in a complete mess for one surface.  Manually adding seams around the edge of the model to slice it into 6 segments results in a complete and utter mess. Doing a cube projection ends up in a complete and utter mess.
So I am now trying to add seams around the ends of each and every hole drilled in the cube - however there are hundreds of them and doing it manually will take all week - with no guarantee of success.

Is this the right way to do it? Manually adding seams to the top and bottom edges of every hole drilled through the cube? Is there a faster way of selecting these edges to add seams? (the fastest way I have found so far is to look at it obliquely and do a box select around a hole in vertex mode, then add seam, then move on to the next hole).

I think part of the unwrapping nightmare I am having with this model is the horrible mess the boolean operator has made of the mesh. It seems to have made faces overlapping each other which isn't good. Not sure how I go about fixing that kind of thing. (update: adding enough subdivides to my cube solves that, and now I can use a smart unwrap, so this now isn't a problem as such, but good to know how to deal with this kind of thing in future).

Hit Shift+G in Edit mode while having one of the edges selected that you want to mark as a seam.
This brings up the select similar dialog which offers the possibility to select other elements by similar properties (in your example perhaps edge length)
Another way to speed things up is box selection (B) in edit mode or circle selection (C) in edit mode. If you want to get certain stuff out of the way while selecting hit H to hide elements. Just make sure you unhide them before you unwrap.

Oh yeah! Shift-G is the magic sauce I was missing! TVM!


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Unlinking vertices/edges/faces in Blender
I have an object that I'm trying to edit in Blender and unlink all possible connected faces of the same selected.
So, bottom line, my issue is:

I have an object and add it in Blender. Then, I am selecting a face/vertex of a specific part of that object;
To select all linked, I'm using ⎈ Ctrl + L (as shown in the image below - the SCREW on the left side);
As you can also see shown in the image, the SCREW on the right side has not been selected - therefore I assume it is not linked to SCREW on the left side and no need to unlink;
However, if I open the same object in another 3D software (i.e.: Substance Painter) and I'd like to fill in with a color the SCREW on the left side, that color is applied also to the SCREW on the right side and yet, they seem not to be linked in Blender.

What am I missing here? Is there any way I can achieve this? I would like to unlink these two and to be able to fill them with different colors. Thanks!

With ⎈ Ctrl + L you only do a selection of linked vertices. What you need is to unlink the materials. You probably have one material on both screws, you need to select one screw and apply another material to it.
You can also probably adjust your UV map so the UV maps of the screws are not overlapping, this way you can use the same material on both screws.


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how to convert shape to volume?
I have a 3d model (.stl) of building and I want to use it in other software.
The walls of the model are built with shapes, and I need the walls as volume.
There problem is that the model was made by shapes instead of volume.
How can I convert the shape to volume in blender now? any functions?

You just have to fill the outer edges (the boundary edges loops) with other surfaces in order to achieve a confined volume. There is no such thing as "solids" in B3D mesh editing, only enclosed volumes.

I tried it but it didn't work, I guess it is because the volumes are not completely closed. I have added the new picture.

Suggest adding a link to stl or a blend file. https://blend-exchange.giantcowfilms.com


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Eevee render lighting issue
been trying to do some product animation, and my issue is that my render is showing incorrect lighting that isn't similar to my view port, even with disabling the lights in renders, they're still showing up when I render, even when disabling all the lights in the scene I found out that the issue still persists, and just the phone body alone shows up with this side lighting issue.
pictures are for my view port and the other is with lighting disabled

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

My issue is I'm trying to figure out why the bottom picture is my render result even when I disable all lighting in the scene, and why my render with lights enabled is different from my view port render.

how did you "disable" the lighting? did you use the "eye" icon or the "camera" icon?

are you sure that you've disabled the lights for render? Check your Outliner settings? If you still don't find, please share your file: https://pasteall.org/blend/

@HarryMcKenzie I've disabled using the camera icon "Disable in Renders".

@moonboots here is the file https://pasteall.org/blend/0907ea73009d4bdf818b77909659e2a5

The collection called Collection is disabled for preview but it is enabled for render, so just disable it for render as well:

Also you have loaded a strip in the Video Sequencer, in that case maybe you should disable the Output > Post-Processing > Sequencer option?


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Blender pen tablet wheel not working
the language may be strange using translator. Please understand. If I register the mouse wheel key through the shortcut key of the pen and press it to write, it works only about 1 out of 3 times. If I change it to mouse mode, it works fine, but if I leave it like this, I can't use the pen pressure, and the pen moves around the screen strangely, so I can't use it. Both pen tablets failed. Any help would be appreciated.

Would you be able to tell us which pen tablet you're using? Also, are we to assume you're trying to sculpt with it, as you didn't say?

Which OS? Does your tablet work in other applications?


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How to animate hair without major lag? Hair Dynamics 3.0.1
I have a model that I have animated with clothing in a walking simulation.
My process was to rig my model using Mixamo, import that model into marvelous designer to animate the clothing, and then bring it back to blender to animate the hair.
However the hair is extremely laggy when trying to bake, what are some ways I can remedy this and get a clean animation?
Any and all help appreciated, I am still learning when it comes to the workflow/process of things.
Would shorter, less hair do the trick?

Believe it or not the animation of the hair when I previously baked it looked a lot better than now.

(1 side of the hair baked, I have 2 particle systems on the head for left and right scalp.)

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

Basically looking for someone to tell me how I am approaching this wrong so I can correct my ways. Why does the hair specifically spazz out when the animation gets going?

Having more child particles and less "real particles" can help with performance, if you weren't already using the child particle system. You could also try re-keying in comb edit mode to a lower number. Also try "Remove doubles" in comb mode, there might be double particles.


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Finding the index of longest edge with Geometry Nodes
I am wondering if it is possible to find index based on certain attributes, like "index of the longest edge" for example.
It is easy to create a selection from attributes, but I can't seem to figure out a way to get indexes out of them, which I would like to use to calculate further (in function nodes).
In addition, I would like to find such indexes among multiple islands of meshes, imagine a mix between accumulate field node and attribute statistics node.

Does this answer your question? How can I re-sort the points/indexes of an object in geometry nodes?

This could also be a solution: Find highest index value for each Mesh Island. With this technique you can easily find out the index with the highest or lowest value of your choice.

@quellenform I am aware of the sorting post but was trying to figure out a simpler solution to my problem (sorting is much more advanced), and my problem involves finding the longest segment in each spline in a curve (but I don't want the question to be exclusively about it so didn't mention that). Your second link sounds useful I will study it.

here is a simple version using statistics node to get the longest edge with compare float.
https://blend-exchange.com/b/gbYOxbe5

you can use this node setup, to get the index:

To make the edge "visible", i added the delete geometry node to the tree. So if you unmute this node, you can "see" which edge it is. But if it is unmuted, you won't see it in the spreadsheet editor - of course - because it is deleted.

Yes, you are right! I am still learning….


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Geometry node editor: search and select all nodes with a certain name or type
Is there a way to search and select all nodes with a certain name within the GN node editor? I asked about this in blender chat in the past, but no one came up with an immediate solution.
However, I came across this blender exchange answer today and would like some help to modify it for Geometry Node editor.
Is it possible to select all of one type of node in the node editor?
import bpy

#Get composite nodes
nodes = bpy.context.scene.node_tree.nodes
#Get indentifer of the active node
find_type = bpy.context.scene.node_tree.nodes.active.bl_rna.identifier
#loop through nodes
for node in nodes:
    #if node has the same idetifier
    if node.bl_rna.identifier == find_type:
        #select it
        node.select = True

(If this is already possible via an existing addon, please let me know in reply, thx in advance!)

on Blender 3.2 at least this gave me this error: line 6, in <module> AttributeError: 'NoneType' object has no attribute 'bl_rna'.

You need to select (click on) a node first

@Gorgious it did not work with a node selected (my error happens when I have a node selected)

You can modify it this way to get the nodes from a node space. If there are many geometry node spaces, it will use the nodes from the last one.
import bpy

for window in bpy.context.window_manager.windows:
    for area in window.screen.areas:
        for space in area.spaces:
            if (space.type == 'NODE_EDITOR' and space.tree_type == 'GeometryNodeTree'):
                nodes = space.node_tree.nodes

#Get identifer of the active node
find_type = nodes.active.bl_rna.identifier
#loop through nodes
for node in nodes:
    #if node has the same idetifier
    if node.bl_rna.identifier == find_type:
        #select it
        node.select = True

I have GN editor open and a Group Input node selected by it still gives me this error: line 7, in <module> AttributeError: 'SpaceImageEditor' object has no attribute 'node_tree'

for future readers, the updated answer now works


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shrinkwrap complex thing
I'm trying to shrinkwrap a field of objects distributed onto a topographical mesh, so as to make a closed mesh for printing. I have many objects distributed over a guide mesh using the particle system. It looks like what I want, but I'd like some pointers on how to most quickly approximate this array of things with one draped and/or shrinkwrapped mesh.

Hey, thanks for replying. I added an image. I'm new to this forum. There's probably a smoother way to add stuff ... I really want just the stuff on the top - the grey mesh running through all the objects can serve as the base plane. With a simpler test I draped a cloth mesh over it, then shrinkwrapped it, and that was nice, but now it's a bit complex ...


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Is there any driver expression for elif statement?
Is there any way to add if elif and else in drivers?
Given the way we do if and else, here are two examples out of few other things i tried to get the statement right but unable to do so:
var-3.5 if (var<0) var+3.5 elif (var>0) else 1

var-3.5 if (var<0) elif var+3.5 (var>0) else 1

And also if there's any other way to add multiple if/else similarly?

Nest the ternary conditional operator
(var + 3.5) if var > 0 else (var - 3.5) if var < 0 else 1

or for more detailed scripts
import bpy

def x(var):
    if var > 0:
        return var + 3.5
    elif var < 0:
         return var - 3.5
    else:
         return 1

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

And then use x(var) as your driver expression.

Nesting the ternary conditional operator worked! Thankyou! Also thanks for the detailed version!

Thanks.  One thing worth mentioning is the use_self option, which is the object being driven, passed as an argument, for example x(self) and var = self.location.x in the method instead of setting up a variable of the same in driver panel is worth looking into.

Ah! I had tried self driver between translate and rotate not via the script but via the panel, and the object started going crazy.. will try the same thing with the script you mentioned. This will be awesome! Thanks again mate!

To use anything more than a simple python line in a driver you can define your own functions and add them to the driver namespace.
import bpy

def myfunc(var, amt):
    if var < 0:
        return var - amt
    elif var > 0:
        return var + amt
    return 1

bpy.app.driver_namespace['mydrvr'] = myfunc

Then in the driver expression you put mydrvr(var, 3.5)

Thanks! As for now nesting the ternary conditional operator as said by batFINGER worked but will keep this in mind :)


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Wall texturing without slides
My problem is the following:
I have a wall wich I textured with a Uv Map. Because I dont wanna have N-gons in it, I made a triangle. But do you know any other way to texture the wall without any extra slides (in UV map) and without n-gons?
Thanks for your help - this forum helps a lot! :)

I would approach it this way. There is only one additional vertex than the original and it's quad based modeling which has a lot of advantages.
Because it is flat unwrap it using "Project From View".