text:
Image Alpha Background Renders Black when using “Import Images as Planes” 2.0
This is a question about an old question which can be found here. I also found an answer to that question by Cegaton, though the instruction in the answer didn't help me, and I suspect that it might have only worked for the older version. So I'm using Blender version 2.78, I enabled the "use alpha" and it still doesn't work in any view, I used Gimp2 for the alpha channel and exported it into png, and imported as a plane using the addon, the plane is still a picture with black opaque background.
Screenshots:
Picture in GIMP2

Exporting the picture as Png

Importing the picture as a plane

Choosing the picture

The plane in object-solid view

The plane in object-texture view

An Image for you to test on:
Please note I am not sure if the alpha channel will stay there if you download it please let me know down in the comments.

It works perfectly fine for me on Blender 2.78, I'm not aware of any critical changes in that plugin for the last versions. Please indicate what exactly doesn't work for you as expected, preferably with screenshots. Show which interaction mode you use to preview alpha channel, import settings, node setup etc.

@MrZak Thank you for telling me how to improve my question, I will edit it shortly

@MrZak screenshots have been added

As an alternative to checking the Use Alpha checkbox add Transparent shader and mix it with Diffuse shader using image alpha as factor (basically doing the same but manually). This is shown in the answer already linked in your question.

@cegaton the test image has been added

@cegaton wow you resolved my issue! you can post that as an answer!


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ferris wheel rigid body constrain
So i try to make a ferris wheel but using rigid body physics. The ferris wheel itself using a motor constraint and it work just great.
But when i try to attach the cab with point constrain, well it won't rotate fully anymore and the cab just rotating wildly.
i'm trying to rotate the axis of the constraint but the result still the same. How to make the constraint work properly?.
i attach the blend file so you can see what's wrong.
Edit : i'm not going to manually animate this using a keyframe. But i want the physics do the work. The problem that i encountered is the cab wont follow rotating the motor constraint

Possible duplicate of Animating a Ferris Wheel

i don't want manually animate this, but i want the motor constraint do the work

see also https://blender.stackexchange.com/questions/70678/accurate-arrays-oriented-upwards

source: Stack Exchange

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

sort: votes


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VSE: How do I speed up playback in the video preview?
I am trying to scrub through a large video (2+ hours) so that I can cut out a few clips from it. The video preview window is too slow when I click to a new time location in the sequence view.. it can take several seconds to show the preview. I've rebuilt the proxy and timecode indices but this doesn't seem to help.
I'd be happy if I could speed up the playback of the preview. Note that I DO NOT want to speed up the resulting video, I just want to scrub through the video to find the right places to cut.
I've tried the following approaches:

Increased the memory cache limit to 4096. The preview is still just as slow.
Rebuild proxy and timecode indices using "Record Run" and a proxy size of 25%. This did not help.
Speeding up the video using "Time Remapping" in the properties window. This speeds up the video preview, allowing me to scrub through the video but when I turn the time remapping back to 1:1, the position in the video changes so I lose the place I wanted to cut.
Applying a speed control effect strip. This has the same problem as using time remapping.

The source video is H.264. I have heard that re-encoding can help speed up the preview, but I don't want to suffer the loss of quality that re-encoding will introduce.
Is there any way just to set the playback speed to 2x, 4x or something for the purposes of preview only?

What proxy size did you use? Maybe try the lowest possible

Yeah I used 25%.

The video preview window is too slow when I click to a new time location in the sequence view.. it can take several seconds to show the preview

Just hit this myself after not using the feature for a while. Did you change the Preview to use the proxy? It's Proxy Render Size under the View tab in the properties (N) pane.

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


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best method for modeling a curved, diagonal rope pattern
wondering what the best way would be to achieve the curved rope pattern seen on the back of this macrame chair: https://i.gyazo.com/48a19b01a2d7430d2f66ed964814e081.png
I've spent hours trying to figure out the best way to achieve a similar result. I've got the base of the chair down as it's a flat shape but the curved back is really throwing me for a loop. I've tried the tissue addon (to tessellate around a similar shape), I've tried a curve modifier, I've tried messing with array, and I even tried manually adjusting each individual rope, but I'm left frustrated and hoping someone might have a better method or suggestion!
here's what I've got so far: https://i.gyazo.com/d61f2366e000a05c30035f71d5bf3e24.png - very basic as I'm hoping to figure out these back ropes before adding additional details. any help is greatly appreciated! TIA.

this could be usefull https://www.youtube.com/results?search_query=how+to+make+a+braid+in+blender+

thanks! i ended up modeling it by hand but these tutorials will definitely be useful in other areas.


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How to add circular flame restricted within an object?
I need a flame inside the following structure:

The flame needs to be realistic like a bonfire, conical and pointy. Something like this(for shape of flame only not textures and color):

I tried a sphere for domain and flow:

But it gave this result:

The flame needs to be restricted in the bowl like structure.

It's unclear what you are asking. You have a poor quality reference picture of a cell shaded flame, however your screenshot shows what seems to be an attempt to make a photo-realistic flame. Please clarify what you are after. Please give all the relevant context of your desired results as well - the approach can be very different for a single still image and animation. There can even be different kinds of approaches depending on your camera movement.


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Render pass with denoise node not saved when rendering thru command line
I'm a noob Blender user but a long time 3DS Max user.

I have set up render passes to be saved as separate EXR file.

All passes render out and saved in the correct place when test rendering within Blender.

However, because Blender does not support frame range rendering (e.g. frame 0-100 then 200-300), I was forced to use command line to do this. This is where the problem begins.

When using command line rendering, all frames are rendered but the AO, DiffInd, & GlossInd pass wont save.

I suspect this was due to the denoise node.

It seems command line rendering is buggy when used with denoiser node?
I'm a noob with command line but this is what I used...
blender.exe -b "[file destination]" -s 0 -e 90 -a -s 140 -e 230 -a
Any ideas?

This add-on might help, seems you can set the frame range easily and there is an option to render using the command line as well. Have you already tried that?

Loom looks great and may sort out the sub-issue of frame range rendering, thx!!! I will check it out and test whether it also sorts out the denoise node issue too? In the meantime, I would still like to understand why the denoise does not save when command line render?


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Mantaflow problem: I can't get any particles to bake in a closed shape anymore
I'm working on an animation using mantaflow and I'm having problems trying to increase the amount of liquid that my liquid domain emits. I tried scaling up the volume of the emitting geometry but it just got messy and then I tried starting from scratch but nothing is working. I also tried flipping the normals of the effector's geometry and removing all modifiers. I even started the animation from the beginning again, and I followed the exact steps I took the first time it worked but it's either not emitting particles or filling the whole domain with liquid. I need some help desperately!! I'm going crazy over this...
the first image is what I get now and the second is what I was doing a few days ago... don't know where I went wrong...

It's a bit difficult to know what's wrong from your limited description, but one problem with Blender is that Domains that based on a Cache that is "Replay" often doesn't clear the cache when you've made changes.  Try setting the Type to "Modular" and check the box for Is Resumable.

hello James!! thank you very much for your reply, I'm sorry my description is limited, I don't know much about technical terms so it's a bit hard for me to explain... I've already selected modular resumable cache type for every bake I was doing before, but it still didn't work. I think I might try with version 2.8 (I read somewhere it might be a bug of the newer versions) or opening up the collision object mesh. what do you think about these solutions? thank you very much!!

I have not found much difference between fluid simulations in 2.8 and 2.9.  Have you completely deleted the cache folder of the fluid?  Not sure about your "opening up the collision object mesh".   You can use https://blend-exchange.com/ if you want to share your blend file; you can remove any objects not involved in the problem if you have "proprietary" work.

Hello James!! Thank you very much for all of your help. I was finally able to fix it yesterday by opening a small hole in the mesh of the containing object. I think I must have been a problem with the normals after all. I did remove all the cache of the fluid too, so maybe it was that. Thank you!!


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How do I make the shadow catcher show what's under it instead of the background colour?
In the image below you can see a cube, a shadow catcher that is under the cube (Looks like a grey plain), and a red plain under the shadow catcher.

Right now the shadow catcher is catching the shadow, but everywhere that isn't a shadow, it shows the colour of the world background.
I want it to show the shadow, and then show the red plain underneath where it isn't catching the shadow.
Here is an example with an HDRI:

As you can see, the shadow catcher correctly catches the shadow, but it doesn't show the red plane underneath. I would like it to catch the shadow, and display whatever is underneath it.
I am using cycles with GPU, shadow catcher is ticked on the upper plane.

is that screenshot in render mode or viewport shading mode; or is it an actual render?  If it's in viewport shading mode, that's actually EEVEE and your shadowcatcher doesn't work as such.  If it's render mode or a render and you have Cycles set as the render engine, please check your visibility settings in object property and verify that Shadow Catcher hasn't come unset

Hi Marty, this is a rendered image. I am rendering in Cycles using GPU. Shadow Catcher is ticked in the object properties of the top plane.
My Goals is to get the shadow catcher to catch the shadow of the cube, but also show the red plane which is underneath.
What the shadow catcher is currently catching the shadow of the cube, but everywhere that the cube doesn't cast a shadow, the plane displays the 'world background'.
I have verified this by:

changing the brightness of the world.
making the world background transparent.
Using an HDRI.

Did you see this one? https://blender.stackexchange.com/questions/70230/transparent-shadow-catcher-under-hdri-lighting-in-cycles?rq=1

Or this? https://www.blendernation.com/2017/04/17/use-new-blender-shadow-catcher/


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How do I control scenes switching
I currently have two scenes in the Blender.
When you enter the game the first scene comes up and when you press "play" the second scene comes up. I've managed to have done that.
Now the third scene is a video.
I want the third scene before the second scene and the game to be continue after the third scene (Video) finishes.
How can I do this, ask anything if you're confused by question or want me to clarify something.

How is the video set up? Is it actual video, or is it a live animation in the game engine?

It's a video, I want it to fit the whole screen and fade out.

Because you are using an actual video, Blender doesn't know when it's finished. At least not if you use a plane and a video texture. In that case, as soon as the scene where that video is located gets activated, the video starts playing.
I program all everything that's scene-related to the camera, since that is an easy object to find and it isn't used to program so it's a clean space. Here I connected a 'scene' actuator to whatever setup you use to click the 'play'button. It should be set to 'set scene' and include the scene you want to activate (which in this case is your video scene).

So now, once we click 'play', we should get into the video scene and the video begins. Since Blender doesn't know when it ends, we should know. Therefore you should take a look at how long the video is (in seconds). Then keep in mind that the refresh rate of your game is by default set to 60. This means ever 'tick' in your game is a refresh. We can use this to let Blender know exactly when to switch over to the next scene.
Here I used an always sensor with a positive pulse trigger set at a skip of 0. This means that every time when the game refreshes (60 times per second) the always sensor sends a true signal to the controller. Now we add a game Property. Give it a name and set it to 'integer' mode. Make sure it's set to 0. On the always sensor we added, add an 'and' controller and after that, a 'Property' actuator. Set the mode of the actuator to 'Add' and set the value to 1. We also need to insert the recently created property in the actuator.
What we're doing here is adding 1 to the property 60 times per second. So when one second has passed, the property is 60. If your video is let's say 10 seconds exact, we know that we have 10 x 60 = 600 refreshes till the end of the video.
Add a 'property' sensor and set the mode to 'more than' (equal could work too, but anything causing blender to skip a refresh could make it fail). The value should be set to 600 in the case of 10 seconds and of course we are going to use the same property again. Onto this sensor we need to add an 'and' controller and a 'Scene' actuator. Set the mode to 'Set scene' and insert the scene that you use for your game. Now, once the video has ended, your game will start.

Let me know if this helped for you!

It's explained precisely and exactly how I needed it to be explained.
Thank you, I will try apply it now... If there are problems I'll reply right away!

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


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3D interactive model for exporting Interactive html/JSON
Apologies if this is an inappropriate posting, but I am new to Blender and not sure where to direct this, so any advice or suggestions will be much appreciated.
I am trying to create a 3D interactive model of a house in Blender that can be exported to HTML/Json using Blend4web.
I am progressing with the modeling side of the project, but struggling with the interactive aspects, specifically 'creating a menu' and basic animations linked to the model. I appreciate this is not something that can be simply explained in stackexchange, but would be grateful if anyone could advise whether Blender (Blend4web) is a good way to achieve this. Alternatively, if there is a different source of information that could provide an answer I would be keen to find out more.
Many thanks in advance.

Blend4Web should be more than capable of doing what you wish, you may have better luck and getting better answers at the official Blend4Web Forum I'd strongly recommend watching some tutorials and getting a good handstart at grasping the basics before asking any questions.

You are on the right track. You may need to study some animation basics for Blender. To see if this is what you are after, Have a look at this. There are a number of YouTube channels that deal with Blend4Web.
https://www.youtube.com/c/WillW

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


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Can I sculpt a group of OBJs
I have a group of OBJs (imported with vert order and poly groups intact),  specifically two upper arms and I want to sculpt one and have it mirrored on the other, but I do not want to combine them into a single OBJ, because I need to  export them separately, with their original vert order poly groups still intact.
I have them grouped, but when I go to sculpt mode I only have one OBJ selected,  and I can't seem to sculpt anything.
I'm probably missing something real obvious, or maybe trying to accomplish  something undo-able.
Any insight is appreciated.

I'm looking to sculpt not edit,  but I assume the same applies. If I combine both  objects into  a single object and then sculpt them  as such,  will it keep  the vert order and poly groups intact(with  the same internal names),  so  that  I can save the file,  delete all the points on one side,  export,  reload the file,  and repeat the process for the other side?
I need to  have a mirrored sculpt with  all internal  names remaining the same,  and still  be able to  export as separate OBJs.

Okay  a little trial and error,  and I've figured this out.  I need to export both  objects together from  the original program(not Blender),  keep  the vert order,  and poly groups intact. Import into  Blender, still keeping everything intact.
Go  ahead and sculpt it as I normally would.  Save the file, and delete one half of the object,  and then export that(also  keeping vert  group order,  and poly groups).  Do  NOT save.  Close the file, open it back up  and delete the other side and export.  I now have the original two models,  right and left,  with  all internal  names intact.

And where and when do you do the mirroring of your arm?


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F12 doesn't render but opens object Parenting menu
Firstly, I am completely new in Blender. I am trying to follow a tutorial and try to render my first sculpture from Camera's view using F12 key. Instead of rendering it just opens Set Parent To menu.

screenshot of my current workspace

Make sure you are using the default keymap

I haven't changed any user interface. My keymap is set to Blender as default

Are you using an AZERTY keyboard?

You were right, I did use azerty keyboard. I have disabled it now and use just English (United States) layout. But Blender still doesn't render when I press f12 and opens parenting menu. I am looking for other shortcuts that don't work. At this moment I haven't found any.

What OS are you running? Is there some way you can check to see if your F12 key is really being interpreted as F12? (such as xev in an X server)

Your can render by using button RENDER here. And try to press Ctrl+P(it is supposed to be set for parenting objects)

Thank you for your reply. I did try pressing Ctrl+P it opened the same parenting menu like f12. I still wonder why the shortcut is not working tho


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How to demonstrate Archimedes Law in Blender?
I would love to demonstrate Archimedes Law in Blender. I understood that it is not possible to have an object float in a fluid because the Blender fluid does not exert a force on an object.
However, is it possible to do this with a particle fluid? Do particles exert a force on an object? Rigid body? Obstacle?

It's not clear to me what you mean when you write "demonstrate Archimedes law". Do you merely want to illustrate the change in the level of the surface of the virtual fluid caused by splacing the virtual object into it? But the problem, I think, is that to calculate the change in the level of fluid, you need the density of of the object, and the density of the fluid, and Blender in and of itself does not track that. It does seem to me that you could create a "game", wherein you could get user input of the densities, and use those figures to calculate the displacement.

It's semi possible with Blender Molecular addon. You can create two Particles System, one as a water (with estimated water density), and second one as the obstacle (with custom low density). Molecular Addon allow to set density. I've managed to create simple ball drop to the tube filled with water where ball is floating covered in a half. You can change and animate density of a obstacle, but you can't manipulate it directly. It's still an particle.

This is a result: http://imgur.com/CwVl8BP

My idea was to demonstrate Archimedes law: the opward force a fluid exerts on an object is equal to the weight of the displaced fluid. The demo by LukeD seems to demonstrate this, the floating is essential. Im not completely sure how to make this but I will try. So the floating object is a particle system with one particle? And particle systems interact with one another but not with other objects? Isnt that weird?

If this is for teaching purposes, you could, instead, illustrate the following thought experiment:

From a perfectly accurate spring scale, dangle an infinitely thin string. The scale shows zero.
Dip the string into a glass of water.The scale still shows zero.
From infinitely thin, weightless material, construct a 1cm cubed box attached to the end of the string, underwater. The scale still shows zero.
Lower the glass. the scale now shows 1 gram.

The upward force on the box of water, while it was submerged, must have been 1 gram.
This, IMO, has the advantage of showing why the law applies, rather than simply demonstrating that Blender can simulate it.

A string has tensile strength but no compressive strength. I suggest using a heavy steel object directly attached to the scale and slowlydip that into water. The density wouldn't really matter since the scale would go 1gram down for every cm3 below water.

This is possible with the very popular and amazing molecular addon by Jean-Francois Gallant:
http://pyroevil.com/molecular-script-download/
It builds on the Blender particle system, but normally, particles are not real objects, they are only for visual representation, like sparks or rain drops, or smoke, where it is not noticed when they pass through one another.
The molecular addon makes each particle a real object and can adds bonds with others (which act like springs or shock absorbers), which can be cut, when the links become overstressed to a definable point and thus tear or can recombine together again when they touch (simulation of stickiness)
This video shows a summary what is possible with this, showing all the different facets:
https://www.youtube.com/watch?v=x8Fo2slT2WA
I find especially the rope example mind blowing, how many small particles can be "woven" into strings, also this method allows for objects to have volume which can be broken open and spill.
This is a further example of this, how many particles can become fluid like:
https://www.youtube.com/watch?v=RpxEIvCfHns
You just create a particle system and then have an extra settings section

where you can define all these parameters, there are quite a few tutorials on youtube.
As you can define specific weight of the particle in kg per meter cubed, you could demonstrate the Archimedes principle very nicely by using a lower density particle system and then drop a higher density one into it, seeing the displacement.
The only drawback that the addon has is that it does not support GPU acceleration and neither uses all your CPU cores. It is restricted in speed due to this, I don't understand the reasons exactly, but the author told me that these calculations cannot be parallelized, a general problem in physics simulations, since one calculation depends on the result of the one that came before it. CPUs with high individual core speeds (even through overclocking) benefit this addon greatly.
I would recommend that you start with a low particle count for initial simulation and then raise the amount for the final calculation.


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Understanding units setup for STL
I don't understand the unit setup. I need to print the model but its just still incorrect in dimensions.
I have set up length to millimeters unit scale 1.
Exported STL file in meshmixer shows that cube that has 100mm in blender is 0.1mm, how does that work?
Also, blender does not scale the model when changing the measurements.
e.g. A model that has 10cm when I change to millimeters it just show that it has 100mm. Do I have to manualy rescale?
Can someone enlighten me to how to set scale, units and grid size to actually work in the units and export in them as I want?

There's a great addon by Campbell Barton called 3D Print Tools that has a Scale To Bounds button that does what you are looking for.  It is supplied with blender, you just have to enable it.

The STL format does not support units. It just records arbitrary X,Y,Z coordinates of the vertices for each face.  Blender cannot know the units you intend.
blender scenes have their own co-ordinate system.  Unit system and Unit Scale just offer consistent display of properties through the user interface.  The objects themselves remain unchanged, because equally these do not have real dimensions either, much like the STL file they just have an arbitrary X,Y,Z.
To fix the problem with your STL you must enable the Scene Unit checkbox in the STL exporter options as shown.  It is also worth using the Selection Only to avoid exporting unwanted geometry.
.
Please note that the STL importer also has similar settings.

Yep I already check to use scene units and exporting just the model I want. The problem is more in the corelation of unit scale and unit setup. The unit set up itsel does nothing except the number in which is the lenght shown... like 10cm just will be 100mm or 0.1m it does not have effect on actual size or proportions. Its all about the unit scale. When you import model that is 10 meters big and you dont want to actually scale it the solution is not to set up the meters to centimeters you have to set up the unit scale to 0.1 which is confusing rather then just to click meters to centimeters.

I agree it is confusing and something that needs looking at.  So this is where the STL format falls down, and blender follows.  I had tested this in and out of blender and it works well, inicluding setting up odd scalings, however I should have checked with an external app.  I remember going through the same thing when I had a 3D printer,  I'll update the answer when I have time.


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How to cut holes in the back of a curved surface whilst retaining smoothness?
I'm trying to model a desk lamp and I am having difficulty in cutting holes in the back of the mesh. How can I replicate this in this photo?

ẞhttps://blender.stackexchange.com/questions/5856/cutting-a-circular-hole-in-a-hollow-cylinder-without-distorting-the-cylinder  https://blender.stackexchange.com/questions/7928/how-would-you-cut-a-shape-out-of-an-object-using-another-object?noredirect=1&lq=1

There are a lot of different ways to go about doing something like this, but at the end of the day you need to arrive at a situation where you have enough geometry to support both the holes and retain smooth shading. This basically means a ring of quads around each of the holes.
Here is one way of going about this. Start with your shape. In this case I created an oblate hemisphere with 16 segments, twice the desired number of holes. This will depend on your desired mesh density in the end, though.

Select each of the vertices that are going to become holes, and bevel them:
CTRL + B, then V to bevel just vertices. You want your bevel Profile to be ~0.125. The number of segments is again going to depend on what you want from your geometry in the end.
After running the bevel, go to LoopTools (in the context menu) > Circle, to make the holes more circular.

Set your pivot point to Individual Origins, and extrude the selected faces in to create your holes. You can delete them or whatever, afterwards, as suits your needs.

Select the edges that surround your holes. A quick way to do this is to select the edges around one hole, SHIFT + G > Face Angles. Bevel these edges slightly to create your supporting geometry. Use Segements: 2, Profile 1.0.

Now all that remains to to connect up your geometry so that you get back to quads. How you do this will depend on your initial mesh geometry, and the number of segments you used when beveling vertices into holes. The numbers I suggested make this relatively simple. Throw on a subdivision surface to test the result.

Another option entirely is to use inset I, LoopTools > Circle and extrude to create your holes. This gives you a lot more options in terms of geometry. You can select larger or smaller amounts of initial faces, resulting in different amounts of geometry around your holes.

Optionally, if you have a high poly version of your original shape, you can shrinkwrap the new version with holes down onto it, which can in some cases improve the smoothness of the curvature some.

Just use a boolean modifier with some cylinders.


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How to create a horizontal strip inside a circlular plane?
I need to create a horizontal strip from one side of the circular plane to another circular plane inside it.
The result needs to be like this:

I got the outer circles using the inset key like this:

I got this now only an intersecting rectanglular face is to be added but i dont know how to.

Forgot about it @MrZak. Done

It really depends on your final goal but you could do it with the help of the knife tool (K then C to cut orthogonally). Also, use a Mirror modifier to make it simpler:


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How to animate translucency of a material per object individually?
I want to create a video with animated text in Blender 2.8 (beta). I have 3 words (individual text objects) of which the locations are animated with keyframes. They slide in next to each other. As part of that slide animation their opacity should fade from none to full.
I found out how to animate the material (surface: emission) color which unfortunately animates it globally for all objects using it. I need the opacity fading individually for each object. I would like to avoid creating individual materials because there will be a lot of text objects.

First, i will add an object index. It will control witch object will be first, second ets..
Object index are located in Object settings, Relations tab:

Blender haven't logic nodes, so i build it by myself, using simple math nodes:

then i group it Ctrl+G:

And finally, i can reuse it:

Then you can animate Color or Strength or any outer values as you want

You can add a Transparent shader and mix to your diffuse.
Now you can animate the Mix shader factor (use the shortcut  I ).
See the image below:

Unfortunately this does not solve the key problem of animating the material per object. I achieved this in a simpler way already described in the question by animating the color of an emission shader material.


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How do you make a seamless IK > FK > IK switch using drivers?
Is there a way to have a seamless IK, to FK, to IK, to FK, etc... kind of slider? I have seen it to be done in riggify but it uses a python script that only works with that armature and doesnt look very clean. is there a method to do this without the need of scripting and by solely using drivers?
I have tried to do this by having 2 arms, one with IK and the other one with FK. the FK one was supposed to copy the IK one's pose when you switched them, it worked, and vise versa for the IK to copy the FK pose. but I have only been able to achieve FK > IK, and not FK > IK > FK. is it possible with only drivers?

The problem with blender drivers is that if set on a property, they have sole control of that property. There is no way to manually override it later. This is why rigify uses the snapping script to make IK follow FK and vice versa, it retains the user's ability to manually update the bones.


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How to transfer weights between vertex groups on separate meshes
I got 2 objects, 1 has all the vertex groups from the rigged armature, the other doesnt have those, but it has all of the weight paint vertex groups for hair length and density on it.
Object 1 did have these weights for hair, but were overwritten when parenting the mesh to the armature and doing "Automatic Weights" so i lost them and my hair is messed up. luckly i got a backup with those weights, problem is, i cant find a way to transfer those vertex groups from mesh 2 to mesh 1 without overwritting the already existing groups of mesh 1.
its there a way to transfer these WITHOUT overwritting the others?

am dum dum and found the answer like 10 min later.
Answer was to use a Data Transfer modifier on the mesh, have both Backup Mesh and OG Mesh in the exact same position, then enable Vertex trasnfer thingy, select the mesh you wanna transfer weights to in my case "UwU -> Nyaa"
(apologies for custom theme, hopefully its understandable)

this means whatever weights are on the "UwU" vertex group will be transfered over the "Nyaa" group. now the reason they need to be exactly positioned is because its more of a weight projection transfer rather than a seamless transfer.
Another useful and more practical method (suggested by moonboots in the comments, thanks!) is to use the "Transfer Mesh Data" tool, easiest way is to Search "Transfer Mesh Data" and once you click on it you will see similar settings than the modifier.

For transfering vertex groups make sure the active groups on both meshes are the ones you wanna transfer, way it works is transfering Active object's weight over to selected.

could you please make a screenshot of the modifier so that we know exactly what options you've enabled? Also, you could have used the Object > Relations > Mesh Data Transfer tool, but same thing I'm not sure about the right settings

oh.. well its basically the same thing but with a modifier instead of an operation, works kinda the same, annnnd! updated


text:
Using blender script how to modify face parameters (type of face, nose etc) dynamically
We exported sample human object(.obj) and imported into Blender. Using blender script, how can I modify the face parameters (oval/round face etc) dynamically ?
Thanks

You can use MakeTarget to load and apply MakeHuman targets (for example "face round"). This can be done via MakeTarget's UI panel.
MakeTarget also provides a basic programming interface for loading and applying targets. This is used by, for example, MakeClothes.
Unfortunately these features are largely undocumented, but you can try to read the MakeTarget source code to figure out how it is done. See the MakeHuman bitbucket repository at https://bitbucket.org/MakeHuman/makehuman/src/6cee93d5c66ad29d37836daaa3fec6a322751219/blendertools/maketarget/?at=default
If you need to discuss these things or request more help, you would probably be best off with asking about approaches in the scripting subforum in the makehumancommunity forums at http://www.makehumancommunity.org/forum/


text:
How to keep projects of previous blender versions when installing new versions?
I have a Blender version 2.78 build for windows and would like to use the new 2.79 test build. I am unsure as to whether deleting the 2.78 version to install the 2.79 version will erase the projects on it.
Is there a way to do this without getting rid of the projects?

first you do not have to delete the old version to get the new one. But no all your blends are safe. (maybe the startup, userpref will get deleted if you used the install) but all your creations are perfectly safe.

First off, reinstalling Blender won't delete any blend file.
Second, there is a portable version for each release, which means you don't necessarily have to uninstall anything and can have multiple versions at the same time. Moreover, the 2.79 RC1 only has a portable version, no installer yet. So in fact you can't even replace your 2.78 installation.
To use the portable version, unzip it and open Blender.exe, very simply.


text:
How to put a model in a scene with another model
Let's say I make a sword, a shelf and a character. I want to put all three in the same scene with another character and have them fight. I can't figure out how to get models edited and saved into the same scene. Please help. Key words or a English speaking tutorial will help fix the problem. Ty Dwayne Herron.

You can go to File>Append> then go to your other .blend files with the sword navigate to your object folder and double click on your sword object. It will bring it in to your current file.

I will try first thing in the morning when I get off work ty


text:
Why won't my eye texture mirror?
I am having this problem with the mirror modifier with the eyes. Blend will copy the shape, size, location, and rotation, but if I add transparency and create a texture, only the original half renders out texture, while the mirrored one doesn't register the changes.
I've tried deleting the modifier and adding another mirror modifier to no avail.
Is there a fix for this or will I have to keep duplicating the original eye and mirror it manually?

I can't reproduce your error. Are you sure the texture is not on the other side of the eye for some reason ?
Otherwise can you upload a simplified version of your blend file on https://blend-exchange.giantcowfilms.com/ ?

Okay, so I'm currently uploading the file (1 mb is the smallest I could get it) but I've rendered the pair of eyes from all angles with the same result. I honestly don't know what the problem is. I've tried it on Blender 2.68, 2.69, 2.73, and 2.78c all with the same result. It's always the same. Maybe it's the method I'm using to make my eyes?

the bigger question is : since you're not planning on using this model outside of Blender, why not render with Cycles ?

I did render it in cycles, but I like the look of blender render more over the realistic look of cycles.

ok, although Cycles can be customized to pretty much any graphic style by now. But if you're happy with Internal, go for it. Just know that it may be removed in the Blender 2.8x series.

You're using a procedural texture with generated coordinates. It's normal if it doesn't mirror.
If you want this blend texture to mirror while keeping the mirror modifier you'd have to use UV coordinates with an equirectangular projection and using a linear blend texture.
Or you can simply apply the mirror modifier, separate the eyes and put the origin of each one at its center.


text:
Weird Faces when using SubSurf
I am modeling a car wheel in Blender 2.79 right now. I am combining the outer edge of the wheel with the spokes. I did this by:
1.) Joining both objects.
2.) Making edge loops on the outer edge piece which line up with z-values of vertices on the spokes, and snapping the vertices of the spokes to vertices on these edge loops.
3.) Making sure the faces / edges all line up right and flow right (They do, Blender recognizes the edge of the spoke and the edge of the wheel rim as one edge loop, which is good).
My model is pretty low-poly, but I have a Level 2 Subdivision Surface modifier applied on my spokes/rim object, and a few edges are creased. I wanted to join these two objects for this reason: where the end of the spoke meets the rim, it should look smooth and should have an edge which catches light (to look/be realistic).
I also have a Mirror Modifier on the spokes/rim with Merge Vertices turned on, and an array of 10 spokes/segments of the rim which makes the whole 10-spoke wheel (Also with Merge Vertices turned on).
Here is what my model looks like with Subsurface and Smooth Shading turned off.

Here is the issue:
When viewing my object with the subsurface turned on, there are some weird polygons at the top and bottom of where the spoke meets the rim. As you can see, the vertex is pushed outward by the modifier and just doesn't shade right. There aren't any n-gons or anything, as seen in the previous .gif.

So - What is causing this anomaly? What can be done to fix it? It's probably something obvious that I just am not noticing, like putting an loop cut somewhere or something like that. Thank you so much!

I found it tricky to work out as it keeps moving :) From what I can see you have a pole (6 edges) at the top and bottom of the connecting strut. You will need to move this away from the edge and probably surround it with a loop so it does not cause issues with the rest of the mesh. Possibly have a few static shots?

It looks like you have the setting "show modifier geometry in edit mode" activated for the subsurface modifier... Its one of the visibility options in the modifier settings.
I assume this because you appear to have some curved edges, which should otherwise be impossible.
If you turn this setting off again, then the subdivision modifier will behave normally. So no controller-mesh change for edit mode view, yet if you keep the setting "modifier visible" on, you will still be able to see how the mesh is influenced by your controller-mesh changes from edit mode, without the edge problems you currently have.

I'm aware that I have the modifier visible in edit mode. I was using it to point out that the modifier is creating faces that are stretched and don't shade well. Thank you for responding.

These polygons are created by the nature of how subsurf works.
You can fix this by putting on more subdivisions and setting the shading to Smooth on the Transform tab to the left .
Access the Transform tab by pressing T.


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How to rotate particles around the curve/path of their travel with geometry nodes
This is the node setup to morph particles between two meshes by traveling curved path. I want them to rotate around the path while traveling so flow look like turbulent.
I am very beginner at geometry nodes, so specifically at which place, what nodes should I put to achieve that ?

You can use the Tilt value of the curve points in this case.
This value is available in Edit-Mode:

When you trim the curve in your geometry nodes, you get the position and rotation of the respective point on the curve, which you then transfer to the instantiated objects.
Like this:

Here is the blend file:

UPDATE:
OK, I have tried to integrate this better in your example. Maybe this version will help you.
However, I don't know exactly what your final result should look like, so I restructured it and implemented it in a simple way to give you a clue:

thank you very much for responding, actually i didn't knew how to include blender files in question, now i have uploaded two files. 1. Original file which contains nodes as shown in screenshot uploaded by me (two-mesh-morph_original.blend) and 2. my trial file made according to your instructions to rotate particles (two-mesh-morph_trial.blend). i tried to include nodes as per your instruction but i am getting particles location offset to curve and getting very less rotation. this is definitely my mistake doing it. requesting to review my fault. thank you very much again

This is it, that's exactly what I want. thank you so much for giving your precious time. what I actually want is an intro with this effect: particles travels and gathers in the form of some alphabet letters. there are very few tutorials for geometry nodes with particles available on internet, so you did great job for me as well as other blender users who are willing to learn particles with geometry nodes

I tried to imitate/copy whole node tree you just provided above but I am getting different result (two mesh objects came together and not morphing properly).
This is the last time i am torturing you. please point out my fault in this file (take a look when you're totally free)

[Also]: i am getting this error message every time i open that file after re-opening it: "1 libraries and 82 linked data-blocks are missing (including 0 ObjectData and 0 Proxies), please check the Info and Outliner editors for details"

Regarding your problem, there are two things: 1. You need to disable "Local space" in the node "Rotate Instances"; 2. Don't scale the curve in "Object Mode", just scale it in "Edit Mode" instead.

Regarding the error message: Click on "File -> Clean up -> Recursive Unused Data-Blocks", save it, open it again.  ...it looks like some ballast has crept into your file.

Task completed beautifully. thank you so much for guiding a beginner. it's an honour for me to talk with you directly. i am not saying much but you're too intelligent as well as great person that you spend time for noob person like me. i am a 3d modeling artist (3ds max) btw and don't hesitate to ask me for any labour work if you want to get it done. Thank you very much again


text:
Using 32bit tiff for displacement
I am trying to import a heightmap from the UK's GIS data. The downloaded height map is in a 32bit .tiff file. When trying to use this Tiff file for a displacement modifier I'm getting some really odd results. I gather this is because Blender cannot use 32 bit tiff for height maps.
Can I convert these images in Photoshop to be a readable format in Blender? If so what image formats can Blender use for heightmaps?

Update : Including a screenshot with a lower displacement strength to show how the issue looks with a more reasonable value.
Geometry is a sub divided plane with ~100k polygons.

Solved! 32bit .tiff does not work. The 16bit png's I exported do.
The Coordinates setting in the displacement modifier was tiling the texture being used for the displacement map. Switching it to Coordinates : UV gave me the expected results.

Exporting to .PNG is showing the same results if I export from photoshop. I have tried different bit depts ect as well, both 8bit and 16bit.
https://docs.blender.org/manual/en/latest/files/media/image_formats.html

I actually can't see what the geometry of the plane would look like without displacement. It looks like a pattern of mixed tris and quads.

Its just a flat plane all quads mate. Thanks for your comments, solved the issue. Updated the original question.

So maybe you should think about answering your own question instead of editing your solution into the question? The way it is now nobody will know that this question has an accepted answer.

Dont be afraid to post an answer to your own question and accept it as correct. This way it stays in stack overflow pattern and is easyly recognisable as a question that has an Answer.

Instead using the Displace Modifier you can choose to use a Geometry Nodes Modifier to displace the mesh using the tiff image. This allows you to have much more control over how the the image displaces your mesh. The image shows a nodes setup i used using a Geotiff image to create a height map. In my case using the Displace Modifier the tiff image created a NaN Value (an undefined value) in the z direction where the height should have been 0 resulting in loosing the mesh in those areas. I solved this problem using this GN Modifier nodes setup.

How did you make the "group input" node connect to the "image texture" node?

I'm quite sure that the problem here is not the bit depth of the height map but the Strength setting in the Displacement modifier. You have set a strength of 35.1 which is way too high I guess. Have you tried different settings? Have you applied the scale on your object etc.?
Even a simple Blender Cloud Texture looks terrible that high, here's a comparison between 2.0 and 35.1 in strength:

Hi Gordon, thanks for the reply. The height setting is just there to amplify the problem. I have lowered it and included a screenshot of the images settings below. I have tested this image in the unreal terrain system and it works fine there.
https://ibb.co/BzHmGjm

Well, from your screenshot it wasn't obvious that it's just for amplifying the problem. The new screenshot you should integrate into your question by editing it. What I saw there is that the Color Space for the image texture is sRGB, maybe you should try switching to Linear or Non-Color. Anything else is hard to tell since I have no idea how the geometry is etc.

Thanks for the pointers! This is my first post so I'm learning the rules as i go! I get the same results for both Srgb and Linear / Non-Colour. I have updated the post with a comment on the geo, its a plane subdivided to about 100k polygons.


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Error while trying to import
Got this error when trying to import my file as fbx, any ideas on how to fix it?

I find it a common problem with blender 3.0 mostly.

im in 2.83, is it normal too?

Try importing in another format. Download with a different format and test it.

That's the sort of error that often means the FBX file is corrupted in some way.  You might want to try the file with other programs to see if it's OK.  Otherwise, it's possibly a bug in the exporter.


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Uneven thickness on curves with sharp turns
Im trying to make a railing for a boat using curve profiles, but whenever theres a turn greater than 45 degrees, the thickness starts becoming inconsistent.
I've seen solutions that suggest using 2D mode in the curve settings, this currently doesn't work for me as the railing has a slight curve on it that i want to keep.
This is what im trying to achieve in 3D mode.

This is the end result when not using 2D mode.

The reason why this happens is given in my answer here: Curve to Mesh bulges at intersection, the profile is oriented along the curve tangent. So when a curve makes a sharp 90° degree turn, the corner tangent has an angle of 45°, simply spoken. If the profile had a diameter of 1 on the vertical/horizontal curve, at the corner it would only be $\frac{1}{\sqrt{2}}$ height and width in vertical and horizontal direction and therefore thinner than the rest. That's unfortunately how it works.

Is there any workaround for it?


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Boneshape's wireframe drawn the smaller the bone is

I'm using a bone with a complex mesh as it's boneshape, the smaller this bone is the more edges it draws on viewport. why does this happen? is it a graphical thing, or is it a way for blender to calculate small meshes?
Is there a way to prevent this?

Blend file was made using Blender 3.0

can u provide your blend file?

@Chris i have updated the post with a download to the .blend

What version of Blender are you using? I can't reproduce the effect on the GIF on 2.93.0: https://i.imgur.com/CKhkCFW.gif

@MarkusvonBroady I'm using 3.0, apologies for not mentioning in the post

You enabled it in the viewport overlay.
There you can set in Geometry wireframe a threshold value.
You should not worry about it, it doesn't render.

i don't think that's what my problem is, this is not the mesh, this is a bone with a boneshape. the geometry wireframe value doesn't affect bones

So the White hand is not a mesh??

no, the white hand is a boneshape that is using a duplicate of the hand as a mesh. that way it looks like i am selecting the hand but i am really just selecting the boneshape. its an aesthetic thing


text:
Align active camera to view using python
To align active camera to match the current view I could simply pan, zoom or rotate the view. Select active camera from outliner then hit Ctrl + Alt + Numpad 0. I only wonder, is there a way to write this in python?
I have dug into sites and look for a way to hack it. Most of it are related on aligning view to camera, align camera to objects, or outdated. No way I could find on camera to view.
So far, i have found few scripts and this script...
bpy.ops.view3d.camera_to_view()

... this would get me into runtime error "RuntimeError: Operator bpy.ops.view3d.view_selected.poll() expected a view3d region"
and this script...
bpy.ops.view3d.camera_to_view_selected()

...seem made all sense, but I wouldn't know how or where to start with it. Is it possible to write a script on Ctrl + Alt Numpad 0?

You have found the right command bpy.ops.view3d.camera_to_view() but it can't be run as is from the Python console.  The error message means that the op can only be run from a 3D Viewport context.  There are (at least) two solutions:

Create an operator class that performs the operation and make sure you invoke it from a 3D Viewport context.  Here's a class I use for adding a new camera to a scene.

class TOOL_OT_add_camera(Operator):
    bl_idname = "camera.add"
    bl_label = "add camera"
    bl_description = "add a camera in the viewport"
    bl_options = {"REGISTER", "UNDO"}

    def execute(self, context):
        """ Add a new camera to the scene, make it the active camera,
            and match it to the current view.
        """

        camera_data = bpy.data.cameras.new(name="Camera")
        if camera_data is None:
            return {"CANCELLED"}

        my_camera = bpy.data.objects.new("Camera", camera_data)

        if my_camera is None:
            return {"CANCELLED"}

        bpy.context.scene.collection.objects.link(my_camera)
        context.scene.camera = my_camera

        bpy.ops.view3d.camera_to_view()
        return {"FINISHED"}

Override the context.  Here's sample code that will do that:

win = bpy.context.window
scr = win.screen
areas3d  = [area for area in scr.areas if area.type == 'VIEW_3D']
region   = [region for region in areas3d[0].regions if region.type == 'WINDOW']

override = {
    'window': win,
    'screen': scr,
    'area'  : areas3d[0],
    'region': region[0],
    'scene' : bpy.context.scene,
}

bpy.ops.view3d.camera_to_view(override)

Note that this code makes a couple of assumptions; mainly that the interesting 3D viewport will be the first one on the list of 3D viewport areas.  Since mostly we operate with only one 3D viewport this is usually true.
In this case, the example override is overkill and can be simplified to
areas3d  = [area for area in bpy.context.window.screen.areas if area.type == 'VIEW_3D']
bpy.ops.view3d.camera_to_view({'area':areas3d[0]})

You can read more about operator overrides in the bpy ops introduction.  The above code was adapted from this answer to "python - How do I override context for bpy.ops.mesh.loopcut?"
Note that this will only work if you have an active camera.
3.2 Update
Context overrides are deprecated in Blender 3.2 and are scheduled to be removed in Blender 3.3  The replacement is temp_override. The manual has examples of how to use the new function.

Works great, thanks for clear insights on operator overrides. Worth of knowledge

@sirrus you're welcome.  If you haven't already you might want to read What should I do when someone answers my question? and perhaps accept my answer.

Thank you for sharing this about  deprecation on Context Overide... Acknowledged!


text:
Replacement for dupli_list and dupli_list_create
I am updating older work from before 2.8. The dupli_list and dupli_list_create have caught me out though and I am unsure how they were replaced. If anyone could give me some pointers to where it has changed that would be awesome. Here is the code for reference.
BL::BlendData::collections_iterator b_gr;
BL::Collection::objects_iterator b_ob;

            for(b_gr->objects.begin(b_ob); b_ob != b_gr->objects.end(); ++b_ob) {
                if (b_ob->is_duplicator()) {
                    b_ob->dupli_list_create(b_scene, instance_settings);
                              //b_ob->is_modified(b_scene, instance_settings);

                              BL::BlendData::objects_iterator b_dup;

                              for(b_ob->dupli_list.begin(b_dup); b_dup != b_ob->dupli_list.end(); ++b_dup) {

I believe is_duplicator() becomes is_instancer(). If this is wrong then I may be further off track than I anticipated :D
Many thanks in advance!

The new implementation of Instancing in 2.8x is easy, safer and more aesthetically pleasing: depsgraph.object_instances

https://wiki.blender.org/wiki/Reference/Release_Notes/2.80/Python_API/Scene_and_Object_API


text:
Why do I get this error? Loading large text file to Blender
Hello Blender Community,
I am trying to simulate a machining process in blender. The cutting tool used is simplified via cylinder and its position is extracted to space delimited text file from NC Code.
Currently, the code I am running via text editor is
import bpy

with open(bpy.path.abspath("//cutting position trial.txt"),
       'r', buffering = 1) as content:

    for line in content:
        # extract tool position
        x, y, z = line.split(' ',2)

        # create tool
        bpy.ops.mesh.primitive_cylinder_add(
            vertices = 3000,
            radius = 0.5,
            depth = 10,
            location = (float(x), float(y), float (z))
            )

        # add BOOLEAN modifier
        bpy.data.objects['ISO 10791 M1 blank cd 0.0025'].modifiers.new('Boolean', 'BOOLEAN')
        bpy.data.objects['ISO 10791 M1 blank cd 0.0025'].modifiers['Boolean'].operation = 'DIFFERENCE'
        bpy.data.objects['ISO 10791 M1 blank cd 0.0025'].modifiers['Boolean'].object = bpy.data.objects["Cylinder"]
        bpy.data.objects['ISO 10791 M1 blank cd 0.0025'].modifiers['Boolean'].solver = 'CARVE'
        # activate the blank
        bpy.context.scene.objects.active = bpy.data.objects['ISO 10791 M1 blank cd 0.0025']
        # apply modifier
        bpy.ops.object.modifier_apply(apply_as='DATA', modifier="Boolean")

        # Remove cylinder
        bpy.ops.object.select_all(action='DESELECT')
        bpy.data.objects['Cylinder'].select = True
        bpy.ops.object.delete()

The code works for small amount of lines, around 15 lines are tested.
However, when loading full file blender quit after a few seconds and give error file:

Is there something wrong with the code? I thought the file was read line by line so the the problem should not happened.
The complete zip file can be downloaded from:
https://drive.google.com/file/d/1aUYUExuDTMFPYKpgOcB34_cXWutqMTPV/view?usp=sharing
Kind regards.
iwan

can you please supply a representative .txt file, so people can run the code straight from the TextEditor and help out.

added the downloadable zip.

Some of the way there
Here is some changes to get you some of the way there.  Unfortunately I have a late version of 2.79 where the boolean modifier no longer has the solver property, so I can't be sure of result.

add and remove the cylinder once at start and end respectively.
set the cd object as active and select.
reference the modifier when added, apply by reference (name).

Edited script:
import bpy
context = bpy.context
scene = context.scene
bpy.ops.mesh.primitive_cylinder_add(
    vertices = 3000,
    radius = 0.5,
    depth = 10,
    location = (0, 0, 0)
        )
cylinder = context.object
cylinder.select = False
cd = scene.objects['ISO 10791 M1 blank cd 0.0025']
scene.objects.active = cd
cd.select = True
with open(bpy.path.abspath("//cutting position trial.txt")) as content:
    for i, line in enumerate(content):
        print(i)

        # extract tool position
        x, y, z = [float(n) for n in line.split(' ',2)]
        cylinder.location = (x, y, z + 5)
        scene.update() # may not be needed.
        # add BOOLEAN modifier
        m = cd.modifiers.new('Boolean', 'BOOLEAN')
        m.operation = 'DIFFERENCE'
        m.object = cylinder
        #m.solver = 'CARVE'

        # apply modifier
        bpy.ops.object.modifier_apply(apply_as='DATA', modifier=m.name)
bpy.data.objects.remove(cylinder)

Thank you for the reply. The BMesh solver gives wrong result for the operation. Using the Carve solver still result in the same error.


text:
Why can I only select certain colors in the color wheel selector in 2.8?
So ever since I've moved to Blender 2.8 I've noticed my base color wheel is restricted to certain portions of the spectrum. For instance, if I drag my mouse around the border of the entire color wheel, the cursor will only be able to reach a few areas on the edge and otherwise be forced inwards. I've attached an image of where my cursor can reach.

In addition to this, whenever I select (say) a bright pink (BC5AB9) and attempt to darken the colour via the shade slider on the right, it will revert my color selection back to the center and make my material white/black again.
EDIT: by request, here are my colour management settings

I can't reproduce this. My build is from today and I'm on a Mac

Take a screenshot of color managment tab in render settings


text:
Workaround for offset of linked collection? (Blender 2.8)
Linking
Suppose I have a source .blend file with object "A" within collection "A-Collection", "B" within collection "B-Collection", and "C" within collection "C-Collection", pictured below:

Then I link all three collections, separately, into a single new separate .blend file, pictured below:

Note that for each linked collection, the linking process created a new empty and sortof "parented" the collection to that empty.  Presumably that's useful since it allows rotation and translation of the collection within the destination (i.e. "consuming") .blend file, but it seems to be offsetting the empty based on the origin of the source .blend file's axes.
In other words, since "A-Collection" was offset in the source file at x=0, y=-4, and z=-2, it gets imported/linked with a parent empty offset from its geometry by offsets x=0, y=+4, and z=+2.
Question
Is there any way to (1) have it create the empty at the bounding box center (or similar), or (2) manually change the offset of the empty, post-import, to be something more reasonable?
I know I could create a new empty in the consuming file, set its parent to be the linked collection, and use the new empty for rotation, but that approach has the downside of having to find and select the new empty every time I need to rotate, rather than just selecting the collection itself.
edit: Another workaround is to move the linked object to the origin, right-click that linked collection instance in the layers hierarchy, and select "Instance to Scene" to create an instance of the instance.  That approach leaves behind the original instance as an unwanted artifact, but it could be moved into a "throwaway" collection and hidden.  (still not a great approach, though)

TL;DR: Set offset for a corresponding source collection in properties>object>collections  to control where collection will be placed with respect to empty when collection is instanced
It is possible to provide the offset for a selected collections in source file. Offsets can be set for a source collection in Collections Panel of Object Tab of Properties editor
Properties > Object Properties > Collections

If location of collection in source file is 4 units in x axis, then set offset of x (in properties>Object> collections) 4 units. By setting offset we can control how far collection instance will be with respect to it's parent empty(also called Instancer).
Where new collection instances can be create by using add menu or by setting collection in instancer panel of empty object

Collection are the powerful feature introduced in blender 2.8. Blender supports linking nested collections as well. Instancing new collection is equivalent to adding new empty followed by choosing desired collection in instancing panel of object properties.

For collections in action and workflow check the following video from Blender Conference
Creating blender demos glowing tigers and tortured creatures - Daniel Bystedt


text:
Cannot Parent Armatures together with Different Armatures
I have started to create more and more on blender, and after a long while coming, I finally manages to get to the point where I am experimenting with armatures.
However, after making my model and giving it some shape, I found that I can't parent the bone groups together to make the whole item on big model.
I have tried extruding fresh bones to join them to, but it doesn't seem to work.
https://pasteall.org/blend/7d72d859e91d49e4b87fce8e212cbbef
If you look at the model there are five tentacle and in need then to join to the main face.

Hello, could you please explain what you mean by "I found that I can't parent the bone groups together to make the whole item on big model"? You can upload your object here (once uploaded, copy paste the URL it will generate): https://pasteall.org/blend/

Blender Stack Exchange has a supported place to upload blend files that last for longer than the 6 months of pasteall.  If you want your blend file to remain with your question here's (How to add a blend file)

From what I understand, if your question is about joining all the armatures into one armature and all the tentacles objects into one object, the current problem is that your bones, from an armature to another, have the same names, example: the first bone is always named Bone. When you'll join all the armatures together, each bone will be renamed so that you don't have 2 bones with the same name. The problem is that the mesh that have been parented to these bones still have the same vertex groups and therefore can't be controlled by bones that have now different names.
Maybe there's an smart solution to this problem (?), the tedious solution would be to join the armatures, rename the bones, join the tentacles objects, parent again to the armature With Automatic Weights.
Also, your tentacles are rather high poly and you have a lot of bones per tentacles, maybe, if you don't have any reason to keep this so complicated, you should simplify, you can even segment your bones to make them rounder. And you have scaled your armatures which may cause some unwanted deformations, apply the scale in Object mode.

Yeah. I like to add a lot of polys and then decrease them as i see fit. Also I am unsure if I can remove the bones because I really wanted to make sure he is a super bendy boi.

I'm not sure it's a good idea to add a lot of poly and then decrease. Also as I said you can segment your bones if you want them to be bendy (Bone Properties > Bendy Bones > Segments), you'll be able to see if you display your bones as bendy bones but it's not necessary


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Shape keys changes only visible in edit mode
The shape keys changes are only visible in edit mode. It only shows the basis in object mode no matter what. Enabling the shape key edit mode also makes all my changes invisible.
When I export the model, it only exports the basis and disregards all shape key values.
blend file:  https://drive.google.com/file/d/1aJXxrqmOYJRy2-AVAWcKCzgX-Usr-7xg/view?usp=sharing

Shape keys of other meshes are behaving normally.
I disabled the addons I used, I tried to separate the meshes, I also tried to reset the vector data for the normals I edited (the last thing I did before this happened). Non of them worked.

Please share your blendfile.

All of your shapekeys are muted.
Look at the empty box to the right of the value in your list of shapekeys.  These boxes are empty meaning that they've been muted.  If you hover your mouse over that box, you'll see a tooltip "Mute".  Pinning a muted shapekey won't do anything; changing the value won't do anything.
For every shapekey that you don't want muted, click in that box.  The box will get a checkmark in it, and the shapekey will start working.


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Can't get GeometryNodes to bake into a texture
im trying to use GeometryNodes to make a ground texture with pebbles scattered everywhere, but i have a problem where these instanced pebbles get completely ignored in the cycles baking process ( the selected to active method ), but renders correctly if i bake from the camera or just use cycles rendering in the viewport.
I've checked for the usual stuff, like rendering being disabled for the object and visibility options in general, but i really cant find a solution to this.
Is this a known problem? Im using blender 2.93.5.
EDIT: i found something new, apparently geometry node based modifications of the mesh such as subdivisionsurface actually show up in the baked image, what gets ignored is everything related to the "point" nodes, so in my case "pointDistribution" followed by "pointInstance".
The weird thing is that it also keeps the previous modifications right before the first point node, so while the subdivision surface doesnt show in the viewport, it does in the final baked image, as if blender decided to skip the point nodes entirely.
What it looks like in the viewPort (base mesh is a cube (also ignore the triple geometry output))

What it looks like after baking


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how to merge toes on foot to create socks?
I am an newbie to blender.
I wish to create socks from the foot. I wish to merge toes to make it seems like a sock.is any convenient way to do that in blender?

I suppose I would try a shrink-wrap first and just see what the results are like

If you do get get a decent result with shrink-wrap, you might try duplicating the foot, separate and remove the toes. Extrude foot region  and retry shrink-wrap

You can also select all your toes' vertices and try Mesh > Convex Hull in edit mode to get a sock like shape around the toes. With that you can go on and for example shrinkwrap the real geometry.


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How to smooth an object in this sitution?I can't smooth it

The wrist looks not smooth enough. so I trying to smooth it with verticle smooth.but it turns to more unsmooth after  verticle smoothing

And I also tried with sculpt smooth tool but I still not get the result as I expect
how can I do make the waist smooth ?
blender file:https://drive.google.com/file/d/1Sh7P0lqkJMQGZYSsexFfER2ifWhOntJN/view?usp=sharing

You could first add topology: In Sculpt mode select the Draw brush, with a Strength of 0 and Dyntopo at 12 px. Paint on this part, you won't see anything for the moment as the Strength is at 0 but it will add topology nevertheless. Then paint on this part with Shift in order to smooth:

Have to make this answer as best accept answer because it really useful for more people able to see it. I would like dyntopo  and then shirnkwraper. thank you for your answer

Maybe consider subdividing the area with less vertices (edit mode) and then applying the smoothing. I’ve often found this helpful. Hope it helps.

Th first thing I notice here is the topology of your mesh, and that is what I think is causing the issue, I'd recommend you to re-topologize the mesh and try smoothing it. Try using the 'remesh' modifier or for more control, softwares like 'Instant Meshes', an open source software that is dedicated to re-topologizing geometry will work great.


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How to subdivide triangles into four triangles with Geometry Nodes?
I need to subdivide a mesh of equilateral triangles so that each triangle gets subdivided into four new equilateral triangles. I want to use Geometry Nodes because I want to set the subdivision level interactively by entering the level in an input field.
I can achieve the desired result using Edge Subdivision in Edit Mode, but the procedure lacks the interactivity of Geometry Nodes.
The Subdivision Surface Modifier, the Subdivide Mesh node and the Subdivision Surface node, when correctly parameterized, all produce three quads instead of the desired four triangles (see attached images).
Is there other node or combination of nodes that can achieve the desired result interactively?
Thanks in advanced.
Desired result: four triangles (First subdivision level).

Three quads - Subdivision Surface Modifier, Mesh Subdivision Node or Surface Subdivision Node (First subdivision level).

I'm doing this here: Is there a way to subdivide only largest triangles?

One way to do this might be to simply recreate the mesh you want.
It's not clear from your question exactly what you plan to do, but you might find this approach helpful:

Here I simply scale the triangle by a factor of $0.5$, and instantiate it at its own points.
The missing piece in the middle is scaled by the same factor, but additionally rotated by $180°$.
Finally, I merge the pieces back together with Merge by Distance.
(Blender 3.2+)
If you want to create multiple subdivision levels, just put the nodes into a group and cascade them.

Update 1, here's what you're looking for....
If you really want the whole thing to be completely procedural, and keep the subdivision dynamic, then it gets a little more complicated.
It took me a while to figure out the structure too, but you can solve the problem with this:

The principle is the same as what I do in the example above, but a little more mature.
First, I duplicate the triangle and scale the individual duplicates according to the desired resolution, so that its vertices make the centers of the triangles in each row.
Then I filter out the triangles I don't need, and convert the remaining ones into curves, so that by resampling them I get a corresponding number of points for the triangles in between.

Finally, I apply only a few logic nodes to get a correct alignment of the smaller triangles.

(Blender 3.2+)

Update 2, now it's really getting crazy....
Dear Robin, Node-Challenge accepted:
The same principle I use in the above examples can be taken even further and adapted for any mesh.
By not instantiating the original geometry as before, but simply using triangles and moving and scaling their positions, they can be placed directly in the required positions:

Please forgive me for not having time to clean up and document the node tree this time ...there's still room for improvement. But I think the idea should be clear.
(Blender 3.2+)

Interesting and helpful approach. If I understand well this produces only the first level subdivision. Can it be used for an arbitrary subdivision level (2, 3, 4 ... cuts)? I want to set the subdivision level interactively.

@JoeErcolino Yes, of course: just use a group and cascade it.

I would like to set the subdivision level interactively, that is to say by entering the subdivision level in a field without having to modify the Geometry Nodes. Modifying the Geometry Nodes to set the subdivision level contradicts the non-destructive characteristic of GN.

@JoeErcolino OK, I took another look at the issue, and found an interesting solution. However, this would be more for advanced users. Maybe this will help you.

Hey!! cool this update. I was also thinking about it: https://i.sstatic.net/1C0iV.gif. But still difficulties on my side. I'd be happy to talk about that with you.

to me there is 2 issues... a simple one: rotating a part of the triangles. a more complex (for me): being able to apply all this to any mesh composed of tris.

this is my wip, if you don't mind to have a look

@lemon thanks for your feedback/input! It would be good if you create a new question about this. Thank you!

Really great stuff! I'm working on one .. the strategy: expand the triangle(s) to a parallelogram across the shortest edge, delete shortest edge for a clean quad, subdivide the parallelogram, triangulate (by shortest edge method), delete faces beyond the end of the original triangle. I haven't had much time and made patchy progress. I'm sure you could implement it more cleanly than me. But I may post it anyway, when done... eventually ... :)

How hard would it be to preserve face attributes?  (like the Triangulate node does)

@DonHatch Now that the mesh is being built from new faces, you should be able to sample the individual attributes from the original mesh. Unfortunately, I don't know of a way (currently) to automatically transfer all existing attributes.

Interesting. I don't quite follow how I'd "sample the individual attributes from the original mesh" yet. I notice that @lemon 's answer does preserve face attributes-- almost. It's wrong for some of the little output triangles along the boundaries of the input triangles. (Details:the mapping seems to get damaged during the final "Merge by distance" node, for some of the little triangles incident on vertices that got merged. If I mute that node, it seems to work correctly, although of course the result becomes non-watertight. Not sure why that would happen- bug in the "Merge by distance" node?)

@DonHatch With all the techniques presented here, the attributes are not reliably transferred without further action, as the mesh is always recreated. As mentioned, you can transfer certain attributes. Attributes from the Face Corner domain are excluded here, as a transfer is dependent on individual points. However, you should be able to transfer attributes from other domains using the following technique: https://i.sstatic.net/9Mp9GQKN.png

This one isn't going to win any rounds of Node Golf.
Given a set of separated triangles:

It uses the sorting capacity of Corners of Face to find the corner after the shortest edge of each triangle.
Based on that info, extrudes long edge 1 in the direction of long edge 2 to create a parallelogram
Deletes the original triangular face, having stored the ordered point-positions of its shortest edge.

..
I'm afraid there's so much capturing and domain-wrangling, the above picture is barely readable.
Anyway, once you're there, you can subdivide and triangulate the parallelograms by shortest edge:

.. and detect normal-viewed 'left' or 'right' of the  short edges of the original triangles to delete the unwanted halves of the parallelograms.
The result seems quite robust, so far:

Why shouldn't this wonderful answer win a prize!? I think the idea is great!

Well, @quellenform, you can buy me a consolation G&T at the 19th, but I think you won the cup, this time :)

Well, strictly speaking, my solution answers the question quite precisely, but it is unfortunately only applicable to a single equilateral triangle that is flat on the ground.

@quellenform I've yet to find a good way of filling mesh edge-only--loops at arbitrary angles/positions?.. maybe I should post that as one for you to answer :)

One more way to do it: using parametric coordinates of a triangle.
Three steps in this solution:

Defining a right triangle with the good amount of subdivisions
Instanciate this triangle on each face first corner
Calculate the position of the realized instances along their corresponding face corners

-Defining the base shape (right triangle)

It creates a grid 1x1 meters with the good amount of vertices (2^n + 1).
Then place it at starting position (0,0).
Stretch it along Y to ensure the triangulation along the wanted longest diagonals.
Stretch it back to 1 by 1 meters.
Removes upper vertices so that from a grid, we keep a triangle.
An illustration of this steps:

-Instantiate on faces first corner

Triangulate the mesh.
Capture the face indices.
Transform the faces to points, placing each point at the first corner of each face.
Instantiate on there points the right triangle created above and realize the instances so that we can move their individual vertices.
-Calculate the parametric positions

Extract the corners positions of each face (the "corner position" group node simply samples the face corner to retreive its position).
As the right triangle is placed at the first face corner, shift it back from (0, 0) X and Y coordinates. Then extract its original positions in X and Y.
These positions are the parametric factors to go along "corner0 -> corner1" and "corner0 -> corner2".
Then add back "corner0" position, which is the final position to set.

Following @Don Hatch comments, an optimization for the merge by distance at the end of the node tree, as every inner vertex is connected to 6 edges:

Nice technique.  Is there a reason to limit it to powers of 2?  I notice I can get non-powers-of-2 by simply muting the initial "2 ** A" node, which seems to immediately make your solution more generally useful.

Are you sure the "Stretch it along Y to ensure the triangulation along the wanted longest diagonals" part is doing what you intend?  I think this may be working by luck.  Try changing the z rotation just before the triangulation to 360° (mathematically a no-op, but introduces some floating-point roundoff error); the triangulation of the stretched grid turns random: https://i.sstatic.net/AJnrqLb8.png and the final result is messed up: https://i.sstatic.net/V0rspOzt.png

@DonHatch, can you share the settings (blend file) with this issue? But your image shows 360° on Z: this is not expected... keep it 0.

Hi @lemon, I uploaded it here but I don't think you'll find it very interesting... it's just your blend file, with Divisions changed from 0 to 3, and rotation z before the triangulate set to 360°, and saved in blender 4.0.2.   The reason for inserting the 360° rotation is as I tried to explain above: its purpose is to introduce a tiny bit of floating point roundoff error, to demonstrate that the y stretch trick isn't working reliably.  If it was working robustly, that 360° rotation would not break it.

@DonHatch, if you prefer, you can do it like this https://i.sstatic.net/JYgBFT2C.png. Concerning 2**A, yes you can remove it also (i did that because this is the way subdivision is)

@DonHatch, notice that, following your comments, I've tested the posted solutions in a performance point of view. If you're interested, please try that also.

regarding your i.sstatic.net/JYgBFT2C.png,I see that you removed the Y-stretch node before the Triangulate, but there is still a Y-unstretch afterwards (scale 1,0.5,1); I think maybe you meant that to be (1,1,1)? In any case, the problem remains: the "Triangulate using longest diagonal" node is succeeding only by luck, since neither diagonal is longest. So this solution is relying on an assumption that cannot be relied on, and which may break in future blender versions. In order to make it reliably correct, I think we need to shear/unshear, or stretch/unstretch in a diagonal direction.

Regarding timings, I expect that the solutions whch use Triangulate en-masse (such as yours here, and Robin Betts's) will perform much better than the ones that manipulate each little triangle (such quellenform's, and the solution I just posted). I partially confirmed this by turning on Timings annotation in Geometry Nodes Editor, and running it on the icosahedron with your Divisions=9, which is same as my Subdivisions=512. Yours:1.2s, Mine: 6.4s. So yours wins as expected. However...

However, in both solutions, I notice the time is strongly dominated by the final "Merge by Distance" node (I am disliking that node more and more!). So the reason yours wins is simply that it is feeding that node 1/6 as many vertices as mine. If I mute that node on both, I get yours:80ms, mine:753ms So yours still wins, even more dramatically (as expected).

Idea for speeding up your solution (but not mine) even more: give your final Merge by Distance node a Selection, that is, only the vertices that are along the original triangle edges.  I expect that will make that node take very little time, so your solution will be ~80x as fast as mine instead of just ~6x as fast.

@DonHatch, thanks for your feeedback

@DonHatch, I've edited the answer (look at the end of it)

Nice!  Your implementation of the optimization is much simpler than I expected.

Here is my late entry.  It works as follows:

Triangulate, using a "Triangulate" node.

Let n (≥1) denote the number of subdivisions each edge is to be subdivided into (i.e. n-1≥0 new vertices will be introduced along each edge).
Duplicate faces n times, using a "Duplicate Elements[Face]" node.
Call the duplication index j.

Duplicate faces n times, again.
Call the duplication index i.
So the output of this second duplication consists of n² triangles for each original triangle, each one labelled with a distinct pair of indices i,j.  This is the desired number of triangles for the answer; we just need to transform them appropriately.

For each original triangle:

shrink each of its n² duplicates by a scale factor of 1/n, using a "Scale Elements[Face]" node, with the center-of-shrinking for the i,j'th duplicate triangle set to the following weighted sum of the original triangle vertices v₀,v₁,v₂:
   (n-1-i-j)/(n-1) v₀ + j/(n-1) v₁ + i/(n-1) v₂

＝ ((n-1-i-j) v₀ + j v₁ + i v₂) / (n-1)

(Sublety: when n＝1, this formula results in zero vector divided by zero scalar, which Blender evaluates as zero vector.  This is fine, since for n＝1 any shrink-center point will do.)
The result for n＝5 is this (I've shrunken the triangles that aren't right yet, for illustration purposes):

So the little triangles are now all the right size; the ones at indices i,j such that i+j<n are now in their correct positions, but the ones for which i+j≥n are not: those need to be turned upside down and placed into the gaps between the already-correct ones.
We can accomplish that by simply centrally reflecting them all about the midpoint of the original tri edge (v₁+v₂)/2, using another "Scale Elements[Face]" node with scale factor -1.  The result is this (still shrinking the upside-down triangles for illustration purposes).

Subtlety: do not "Flip Faces" on the faces that we scaled by -1!  I think this makes sense, though it is a bit of a mind-bender.  When I tried inserting "Flip Faces" on those faces it made the output incorrect (turn on View3D Overlays -> Geometry -> Face Orientation):

Finally, "Merge By Distance" to merge coincident vertices (and edges), making the mesh watertight if it was originally.

Results look good:

Here is the main node graph:

Expanding the "Figure Out What Center Point To Shrink Each Tri About" node shows the implementation of the formula shown earlier.  Note that this is a pure field / function (no Geometries in sight, all dashed lines), with parameters n,i,j, intended to be evaluated on the Face domain:

Expanding the "Weighted Average Of 3 Points" node:

Regarding attributes:

Face attributes are transferred faithfully, I think (I haven't checked) (and I'm not completely confident in this since I think I have seen "Merge By Distance" wreck face attributes before, specifically when I was playing with the result of @lemon's answer)
I think vertex attributes are transferred correctly on the original vertices; not sure what happens on the newly introduced vertices
Likewise for edge and corner attributes

Note: I'm not very happy with the final "Merge By Distance" node, since it seems to me that has the potential
to wreck the structure of a mesh; e.g. if the mesh is structurally manifold but happens to have unrelated vertices at the same position.  All the solutions proposed so far seem to suffer from this problem, some more than others.
Blend file (saved in 4.0.2)


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How to displace the surface of a sphere with an image avoiding seam in geometry nodes?
I'm trying to make a model of the moon to be 3D printed. This means that I need a real displaced mesh, and shader or material displacements wont work (sorry if the terminology is not right).
I would like to use Geometry Nodes because of its advantages. I've already did it using the old method of image texture without GN, but it presents several disadvantages, specially when you need to make changes in the final mesh.
The problem is that I get a seam where the vertical edges (left and right) of the displacement image meet. It can be seen in the uploaded image along with the Geometry Node Editor. How can this be avoided?
The UV Sphere and all other Blender parameters have its default values.
I'm using Blender 3.3 for Mac OS.
The source of the displacement image is link.
Thanks in advanced.

The UV Sphere and all other Blender parameters have its default values.

I've mentioned that the model will be needed for 3D printing, because I need a real displaced mesh, and shader or material displacements wont work (sorry if the terminology is not right).

if the image isn't repeating itself in the meaning of: it looks the same at both edges....i think it is pretty impossible, because you are using an image. maybe try a procedural way? or use another image? if this isn't your problem, could you pls provide blend file? thx

@Chris thanks for your comment. The image is the all-around height field of the moon and both, right and left edges, are meant to be neighbours, so the corresponding height and grey values in both edges are similar. This means that the image can be repeated horizontally without a noticeable seam.
As I said, I've already did it by using image texture without Geometry Nodes, but it presents several disadvantages with respect to GN, specially when you need to make changes in the final mesh.

@Chris here is the file:
link

i cannot download unfortunately: [1]: https://i.sstatic.net/qMf6j.png it says it's harmful and google did block it

@Chris I don't know why are you getting that message. The link is
https://filedropper.com/d/s/brWIsymG68EB0KcnC9joPKL7k9p8Ga
I still can download it and is a zip file with the same blender file plus the moon image.

FYI, I had the same problem on Chrome as well, fortunately Edge did let me download it. Maybe the MacOS-related files inside the zip tripped it up.

You're using a UVMap for your vector information source, which is in Face Corner domain. This means right at the seam, your values are doubled, because while the mesh has only one vertex there, two face corners are present—both left and right side of your image is occupying those same points. You can get rid of it by simply 'converting' between the two domains using an Interpolate Domain node:

Thanks @Kuboå. Just what was needed!

Could you upload the file in your answer as well? I wanted to try something with it, but I cannot download the original file - none of my browsers allows it and my antivirus software says it's a trojan.

@GordonBrinkmann Sorry, doesn't seem to work for me anymore either. Maybe try downloading from the original NASA site, there's a link in the answer.

Oh, okay then. I thought you had the file since you worked on it. I was looking for the complete file, not just the NASA textures (I have loads of NASA textures).


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How can i animate helicopter blades?
Chopper with blades added,after positioning correctly, because of pasting it from another file with it flat

The propeller blades

I made a helicopter with separate propeller blades acting as a child to the helicopter. I made the rotation animation with the blades in another blender file with them flat then copied the propeller blades and animation from that file and connected to the helicopter as parent/child. However, when i position the blade with its animation data to the helicopter it goes flat and doesn't stay where i positioned because i animated it flat. So i end up with a lop sided propeller blade as the helicopter is at an angle.
The helicopter itself is already animated so i am adding the blades last which has made it more difficult. Is there an easy way to animate the blades so i can easily add to helicopter? I've tried doing it with the helicopter in motion and its very difficult.

If the rotor child of the helicopter it will follow it. You have to animate only the rotation of it.

Does the helicopter had the rotation applied? What happens if you select the helicopter and press ALT+R. Then the helicopter should be aligned to the global grid. If not then the two objects have different orientations.


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Exported model not transferring with UV Wrap to Unity
I'm fairly new to unity so my apologies as I try to work this out.
I finished a model in blender that contains a few objects and uv wraps:
When I load up the obj or fbx export of the entire project it shows up normally with everything attached:

However upon putting the model into unity, the object mesh will only show up and I can't find how to exporting everything as is.
This may be more of a unity problem but I thought I'd try here
Again, thank you for your patience and help ^_^


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How to change shadow softness of light?
The option for softness has changed since blender updated and I don't know where to find it

The bottom one is the old version and has the softness option

It looks like:

Light Size will influence the softness of the light edges and of the objects shadows.

Light Blend will influence the softness of the light edges only.


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Water Material Not Working the Same in Eevee as it Does in Cycles
I am working on a scene where the water needs to be somewhat transparent and reflective (like water generally is). It looks great in Cycles, but when I switch to Eevee, it does not look the same or even close to what I'm going for. Screen Space Reflections is on (with refraction). The closest I could get was switching the Blend Mode to Alpha Hashed in Eevee, but it still isn't right. Is this a limitation of Eevee or am I missing something?
I've attached screenshots of Cycles vs. Eevee.

Eevee works differently than cycles and does not have all the same capabilities. You can try compositing cycles and eevee renders for different parts of your scene using the Holdout shader, but because the water has those reflections, you might just have to do the whole thing in Cycles.


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Changing Default Checkered Background UI Color
I was wondering is there anyway to customize the checkerboard color? I'd like to lower it's contrast since it is very distracting for me. I can't seems to find the one attribute in theme preference. I wanted to know if it's possible to change it before filling bug report to blender devs.
Note that I'm not asking adding custom background for rendering, it's more UI color customization. I do want it to be rendered in transparent, I just dont want it to be showed in lookdev mode.
Thanks.

Now the checkerboard color are changeable in theme preferences
under Preferences > Themes > User Interface > Transparent Checkerboard.


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Can't finish a front car bumper grille
I have a problem: I model a front car bumper grille, but I can't finish it as I want. That's how this grille looks now:

That's how I want it to be:

Help me, please.

First make the rest of the bumper so that you know what shape you need to fit the grill into. Then you can use a Boolean modifier to trim away the parts of the grill that you don't want. Then move the slats of the grill forward and back to finish the shape.
It seems like you a very early in this build. Keep working at it and don't get frustrated.


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Boolean Modifier results in artifacts
I am decided to design a simple car wheel today. It is not meant to be realistic or anything like that; I am just making it for fun. At the center of the wheel, there are supposed to be 5 indentations for lug nuts. I am attempting to cut these in using the Boolean modifier. However, several artifacts appear when doing so. I uploaded a video to YouTube which shows these artifacts, and also provides more information about the whole situation. Please watch to the end.
https://youtu.be/lSZPen6HFE8
Thank you for any help you can provide.
EDIT: Here is a link to my .blend file: https://drive.google.com/file/d/1cocemui28Ql0XiKsitS77Nfk72j1CTLb/view?usp=sharing

please share your file, I think you can't always get the exact result you want with booleans, you often need to rework the mesh after applying, like adding edge loops, it might be the case here

Here is a link to my mesh: https://drive.google.com/file/d/1cocemui28Ql0XiKsitS77Nfk72j1CTLb/view?usp=sharing
Thank you so much for helping!

Your problem is that you have vertices overlaying, so use W > Remove Doubles, with a Merge Distance of 0.01. It will work, but the topology is not very good as you just have one face on the top. You should better create an inset with i, then boolean. The topology won't be perfect either as the amount of vertices of your small cylinder is not the same as your inset. Actually the simplest way to create your hole is to inset then extrude but you may want something non-destructive. In that case, maybe inset and use a cylinder with the same amount of vertices.

Thank you! I had tried insetting before but I didn't get the same results since I did not remove doubles with merge. I also used Auto Smooth, and shading artifacts disappeared!

It can be several issues with Booleons, sometimes can be the underlying geometry you are cutting into, can you provide screen of the wireframe of the wheel, also can be worth turning on auto smooth. Will await screenshot of wire.
its fine for me with auto smooth ticked under object properties.

In the video I sent, you can see the wireframe of the wheel near the end. :)

Hey, I uploaded my .blend file as well if you'd be kind enough to look at it! https://drive.google.com/file/d/1cocemui28Ql0XiKsitS77Nfk72j1CTLb/view?usp=sharing

updated answer with picture of auto smooth turned on using your blend file

Thanks! It worked!