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Help me understand Renderers, especially in 2.8
I was struggling to follow a 2.79 online tuts in 2.8 until I found this thread 2.8 Adaptive Subdivision
So now I see that Adaptive Subdivision and MicroDisplacement are part of the Cycles Experimental Renderer.  As a new user and beginner of Blender this was confusing to me, I thought the difference was due to the version not the Renderer. (please don't waste our time by criticizing my choice to use 2.8 to follow 2.79 tuts, it's not helpful)  Here are some specific questions that might help me understand better.

Why does Blender have several renderers? {Workbench, Cycles, Eevee}
(2.79 had BlenderRender and why did it go away?)
What criteria should I use to determine which one to use?  (I was struggling to find Adaptive Subdivion in Eevee as I expected it to be part of Blender, not tied to a specific Renderer)
What other items should I be aware of that will differ from Renderer to Renderer and might contribute to my choice of Renderer?
Since Eevee is newer than Cycles, is it a BETTER Renderer?  If so, why doesn't it support Adaptive Subdivision or is it simply baked in by default?
Can you point me to any educational material that explains and compares these?
How long will Adaptive Subdivision be 'Experimental' - I've found videos that go back a bit and would have expected Adap Sub to have moved out of experimental into core
My main goal is to texture terrains generated from heightmaps .  What is the BEST Renderer for that task?

Thanks in advance, this is always a helpful site

Related https://blender.stackexchange.com/questions/123164/what-is-lookdev-mode-for-in-2-8/

Possible duplicate of What's the purpose of the EEVEE rendering engine?

https://blender.stackexchange.com/questions/87923/will-eevee-eliminate-the-need-for-cycles-and-rendering/ also https://blender.stackexchange.com/questions/120372/how-does-eevee-work

Thank you for stating your question so clearly.
1.) Many different representation engines in Blender 2.8 will allow you to navigate, differentiate, represent volumes (smoke, fire, etc), heavy dense scenes and realistic light bounce materials and environments. You´ll learn in time how to use them to the best of the representation for each case.
2.) Workbench: when you want to see lot of objects inside an archviz scene, EEVEE: if you want to see the completed materials/textures in real world light conditions), etc..
3.) Eevee doesn´t support adaptive subdivision like in cycles at the moment. No further notice have been given about this, don´t know if it will be implemented, as the engine per se, is different than Cycles (EEVEE is screen space based effects only)
4.) Right not there isn´t a specific tutorial, but upvote me as answer and click on the left side checkmark icon of this post because:
1. When you model: Work in workbench using wireframe
2. When you sculpt: Use workbench in solid mode
3. When you create your materials/textures: use look and dev mode (flat light or Hdri or Studio light)
4. When you´re lighting: Use look and dev
5. When your're ready to render switch to EEVEE or CYcles.
There are some nodes that will only work for eevee, not for cycles, and backwards.
The only way to know what to use is to ask around or watch tutorials. No guides specifically filtering those nodes have been created up until this moment.
4.) To answer this you need to search for "screen space effects". Which in addition "What the camera sees is computed into a 2D space, takes the info of any normal or UV space around it, and applies a certain code to "compile" a result of light calculation".
5) There are many tutorials. I´d bid you to search for "eevee light reflection probes" to start with.
6) Experimental only means not every user has a necessity to use them, so it´s best for the system to have it "dormant" until this function is needed. Blender makes a "wake up" call to many functions in it´s code. They are activated at the time of need. This is the reason why you open Blender, loads up necessary components and starts up in less than 5 seconds. Compare that to a larger (fully loading .dll applications that can take up to 1:30 minutes to load up).
7) World machine is superb. Just keep generating procedurals using Cycles. The only way for now. Unless you bake a high poly displacement and THEN take that huge poly count into EEVEE. But this is just a work"around" method.
BFCT_Schiller


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Basic Interface 2.8: How do I get Shader nodes in view to be centered and large on first click?
I have a project with multiple objects.  I work on the project for a while, save it, quit blender, reopen it etc.  I click on an object in the viewport and open the Shader view and cannot see my shader nodes.  I have to scroll out until I see my tiny node setup, then I have to center it and zoom in.  Is there some simple basic way to tell blender to open the shader nodes so that they generally use available visible real estate by default?  It's a small issue but irritating.

Press the Home key to put all the nodes in view, press the period key on the keypad to center on a selected node.
Also, if you're on a mac, you might check this: How do I emulate the Home key on a mac laptop in Blender?

source: Stack Exchange

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

sort: votes


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2.8 Rigid Body settings and how to use?
Thanks in advance for any help on this.  Just playing around with Rigid Body behavior based off/extended from this tutorial, https://www.youtube.com/watch?v=-4uFt0m5I-U
I keep tweaking and tweaking the Rigid Body properties of the 'earths' and the sandbox and just can't seem to get them right, I assume because I really don't understand what each control does.
I want to simply drop these 'earths' into the sandbox and have them bounce around a bit, roll around a little and settle into the low spots, in a natural looking way, perhaps what you would expect if god were playing marbles with planets.
But they either immediately explode outward in all directions too quickly escaping the sandbox OR they descend very slowly and settle too quickly.  I've made my test blend smaller and simpler for faster bakes and retries but the iterative process of struggling to find the right settings is time consuming and frustrating.  I assume that if I understand the Rigid Body Controls better I can make better decisions -but how to learn them?
I think that Friction and Bounciness are probably obvious and while I think I understand margin, I suspect I don't.  I keep playing with Friction, Bounciness, Margin, Damping Translation and Rotation, mostly on the earths but also on the sandbox but I just never can get what I am trying for.
In this case I am not looking for help on the right settings, I am looking for help to understand the settings so I can reduce the amount of experimentation/iterations required to find settings I am happy with and when parts of the sim start working as desired I will understand what to change next and what to leave alone.  Right now it's all just a crap shoot.
Start Image
 -
Initial separation

Sandbox Physics

I just tried something similar and it worked OK, I'm guessing your spheres are too close / touching on the initial frame. This will upset things.
Here's my result-
https://www.dropbox.com/s/cdtnwukjwakg6kc/RigidSpheres.mp4?dl=0
And here's the scene-
https://www.dropbox.com/s/aw6pmq5tmis0kee/RigidSpheres.blend?dl=0
If you move my spheres so they're touching/intersecting they repel each other as they start to fall.
Cheers
Mark

Thanks Mark - I have recently learned this too, even if they start out NOT touching, they can fall into each other and explode if the physics are not consistent across the set.  The key seems to be to make sure that they don't touch and don't touch too quickly or too much as they fall (due to different physics).

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


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Mesh is Transparent
Just playing around with some models and I'm trying to make this look like a crystal but its transparent and its not supposed to be. Someone mind telling me what's up with it?

maybe change the alpha value in the shader???

That worked a charm can you explain what the alpha property does though? Because I didn't think it changed transparency just emission strength (I don't know how to use nodes so I'm watching tutorials and just kind of guessing at what stuff does)

Well.. alpha drives transparency: 1 is not transparent, 0 is full transparent... no more

It is easier to think Alpha in terms of occlusion: 1 fully occluded, 0 no occlusion.

@lemon answered perfectly it was the alpha value.


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I am making a rubiks cube and cant figure out how to get the pieces to move correctly
I can't get the Rubiks cube cubes to rotate and translate the right way without excessive animation and I'm wondering if there is some way to assign the cubes/pieces a certain path that they can follow but can't leave

Local rotation is your friend!
Here's what I'd do:

create an 'Empty' at the very center of your cubes
snap the 3d cursor to that Empty:

Set the pivot point to '3d cursor':

Choose 'Local' rotation mode:

Then select your face cubes and rotate, using axis-constrained rotation (i.e. only one axis at a time).  If you use Local mode it shouldn't matter what crazy orientation your cube is in, your rotation will occur relative to the rotation of the cube:

If you rotate using the 3d Manipulator, it'll stay in Local mode as long as you don't change that dropdown.  If you use hotkeys, press the axis TWICE to be in local mode.  That is, press 'R', then 'X' once, then 'X' again, to rotate around the X-axis in local mode.  You can see in my image those red lines shooting out of the faces that show the axis of rotation.
Hope this helps!


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how to snap 2 specific points
I'm trying to make a low poly lantern of some sort and I want to get a frame. To do this i'm trying to get cylinders to line up with the edges of the bottom of the lantern however when i try to snap the cylinder it is facing the wrong direction how can I A) get the cylinder to face into the lantern instead of hanging off the edge and B) how can i make sure that it is centered so that it isn't skewed off to one side or another (basically how can I make it so that all the vertices are lined up straight)

Hmm... Could you zoom out and get some more pictures? I think I have a few ideas... It looks like your 3D cursor is not centered, maybe snap it to the world origin first? Perhaps I don't quite understand.

Basically you want to use the 'Snap with Active' part of the snap feature. The active element is highlighted white by default instead of orange, and it is the individual vertex/edge/face you most recently interacted with. If you need to set your active vertex to something new, deselect and reselect that vertex.

Then it's just a simple matter of selecting the correct active vertex and snapping your mesh into place.


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Using/Converting pigm materials for blender
I have found some nice texture materials which are pigm format.  Is it possible to use these in blender without conversion?  If not, how easy would it be to convert them?
Here's an example of one which would be perfect for my current project.
https://www.indigorenderer.com/materials/materials/205

Out of curiosity is it going to be used for ncars interiors?

No, I think it would work good on rope nets


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match two mesh curves
I've got a situation where two objects meet and they both have curves.  I need to make the white portion on the left side match the curve of the gray portion on the left side.  The inside the white area isn't really a curve, its the gray portion showing through.
I've tried cutting, scaling, and just can't get it to look right.
Any ideas?
Thanks,
Gwfami

It' s unclear which "portions" meet. The inside? Explain again.

maybe share your file: https://blend-exchange.giantcowfilms.com/

Sorry about the misunderstanding.  I ended up hand matching each portion so that the curves lined up properly.  I was looking for an easier, automated route instead of a manual labor intensive version.

I think this could have been easily done using booleans. Look at this workflow https://www.youtube.com/watch?v=Gj2ZjpiDUWY

Thanks.  That gives me some ideas.


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Extreme lag in the viewport directly after Startup
I've just installed Blender on my new Surface Pro 7
(Quad-core 10th Gen Intel® Core™ i5-1035G4 Processor, Intel® Iris™ Plus Graphics, 8GB LPDDR4x RAM) and really can't get it to work properly.
(Blender System Info: https://drive.google.com/file/d/10l_Wgz7lPkp2rcvESULWuxjG8vWTaaSI/view?usp=sharing)
Directly after startup, it is unusable, because whatever I do in the viewport is extremly laggy. The main issue is the viewport. Nonetheless the menu bars at the top ("File", "Edit",...) are lagging a little bit as well.
If I try to move the cube in the startup file, it seems like blender is overwhelmed (https://drive.google.com/file/d/1SS50Ta1a-CLOd4xGaRvic3TBbBQwGDDd/view?usp=sharing).
I've already downloaded the newest experimental Version, same Problem, no Solution.
On my Old Laptop (Quad-core 8th Gen Intel® Core™ i5-8250U Processor, Geforce GTX 1050, 8GB LPDDR4x RAM) everything runs as smooth as butter.
Actually, I really cant imagine that the Surface is to weak for Blender, or is it?!?! I've been browsing for this topic a couple of hours but couldn't find something fitting, so I would be really glad if someone can help me :D

You may want to compare gpu ratings.  There are definitely web sites that do this ... https://www.videocardbenchmark.net/gpu_list.php

Check your GPU drivers!

The CPU on the Surface is better, the GPU is a lot worse. Nonetheway, Blender suddenly started to work mostly correct, it works alrigth for me. Thanks!


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Messed up shoulder rig
I'm working on my first character rig. I'm having a bit of trouble with the shoulder. The vertices, even though given 1.000 weight (and auto-normalize is on so it's definitely not dual-controlled) with shoulder.r it still doesn't rotate at a fixed angle with the bone. IDK if that's how rigs are supposed to work. Here's some pictures:


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How do I save a rotated HDRI from Blender?
I just need to export a rotated HDRI background image. I rotated the image:
How do I rotate an environment texture?
How do I save it?
Also, if I could choose between HDRI or 6 cube images that would be great.

add camera, rotate it on 90deg. by 'X' axis., and select Panoramic Type with Equirectangular Panorama type.
use Cycles render engine with just 1 sample.
don't use Filmic View transform.
set Output dimensions as environment map.
render an image and save it in EXR or HDR format!

Would be good to mention an output file format as well ...


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map_Kd missing from MTL file
I am trying to add colours to a cube and export them as an OBJ file for use with a 3d printing program.  When I do so, the MTL file is created, but the map_Kd file is not noted in the MTL and therefore the program cannot use the OBJ properly.
When looking at the object (a cube in this case) using both the texture and material display methods in Blender they both show the colours on each face.
The steps I have followed to create the uv mapping, then the material and texture are:

Switch to Blender Cycles Render
Entering edit mode, selecting all edges, marking the seams (Ctrl+E menu), unwrapping it, and save the UV as a png.
I edit the PNG using gimp/ms paint (simple colours)
In Blender, go to the materials tab and click new
The surface is set to diffuse BSDF, and I click on the Color option, and then select image texture.
Click on Open and navigate to the folder with the png file and select it.
Change the UV view to the nodes view, and in the main window choose to view the texture rather than solid, you can see the colours are now on the cube, and there is a new node containing the new material.
I then select export obj and have the following options ticked:
a) Apply Modifiers b) Include Edges c) Write Normals d) Include UVs e) Write Materials f) Objects as OBJ objects g) Path Mode Auto

Any assistance would be greatly appreciated, have I actually created the material using these steps?  And have I applied the texture correctly?

Sounds like you did a good with the material, but maybe try using Blender Internal render engine and materials instead. Might work better for OBJ export.

thanks for the reply, i need to be able to export the uv mapping, and unwrap the object, and that doesn't seem to work within blender render.  Do you know of a guide I can follow using blender render?

UV Maps are part of mesh data, and thus render engine independent, they are exported regardless of the active one. The OBJ exporter is older though, probably closer to Blender Internal age, I believe it will support texture export better for Internal materials. Also have this in mind https://blender.stackexchange.com/questions/57531/fbx-export-why-there-are-no-materials-or-textures

I face the same problem in 3DS max. The .mtl file references an obj file with map_Kd and as such i can't import it correctly, nor find this .bmp file.

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


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Enable Dual GPU Cuda on MacOs Seirra
I've been using Blender for a few months now and I am not entirely sure I am taking full advantage of my two GPUs.
I have MacOS Sierra, Windows 10, and Ubuntu installed on my machine all with the latest CUDA Drivers, and 2 GeForce 1050 ti SC 4gb GPUs installed.
Rendering times compared to my 15'MBP i7 CPU are obviously better but I am wondering if there is something missing. The smoothest and fastest experience with almost no crashes on Blender 2.78c is surprisingly in MacOS Sierra.
I've got both GPUs selected in Blender > UserPreferences > System and with most scenes I stick to 256 x 256 in performance. I also noticed that Blender Cycles renders one tile at a time, and I was under the impression that with 2 GPUs, 2 tiles would be rendered at a time.
Then again I think this might be due to the system seeing the GPUs as one unit. I should mention that iStat software reads both GPU processors being used just fine, but I thought I should ask anyway.
Any advice or hints that you can recommend are greatly appreciated, thanks for listening.

You mention selecting both cards in preferences so if both cards are there to choose then blender sees both. To be only rendering one tile at a time, I would check the thread settings in the performance tab.

Are your GPUs in SLI or similar pairing technology, or somehow presented at OS level as a single GPU?
If so that will negatively affect performance in Blender, because those systems are generally inefficient and will not fully utilize the power of both GPUs entirely.
Blender however if presented with two discrete graphics cards for rendering in Cycles can make full use of both at full speed without performance compromises, virtually doubling the speed and halving render time.
Having only one bucket while rendering is generally a sign that only one GPU is being detected by Cycles.
If possible tweak your settings in such way that Blender can see both your graphics cards as independent hardware.

Thank you for the advice. I posted a screenshot of the settings as currently set. The only thing I can't make sense of is Blender only doing one tile at a time. (http://i50.photobucket.com/albums/f332/RobertTheDestroyer/Screen%20Shot%202017-07-30%20at%202.13.59%20PM_zpssx6yusbq.png)

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


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Smooth edges are sharp after rendering
I'm a complete beginner at blender so please help in a way a beginner can understand. I'm following the blender guru's blender beginner tutorial on youtube and im on the final 9th episode. I've made a donut and before I put it through a final render, the frosting is nice and smooth. But after I render it, the drips of frosting are sharp and triangular. I have NO CLUE what I did or how to fix it. It makes zero sense and I could really use some help. Heres before final rendering and after final rendering.

Assuming you have a subsurf modifier, check to make sure the render levels are the same as the view levels.

@Brenticus use that as the official answer so sylleth can give you credit :)

@Byron Well your answer was better than the one I would've given... So I'll let you get the credit this time :)

Make sure your render settings for your subsurf modifier are at least the same or higher than your view settings. In the following image you can see view subdiv is lower than render.

Set your render subdivs higher or equal to your subdivs.


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How can I correct more faces at the same time?
I am making this stylized "illusionist pendant", that basically has two halves, that turn forming a heart and open (sorry for the poor explanation). I already have the heart modeled but if I try to rotate half of it the silhouettes don't match up. So how could I fix that?

I have fixed them now, but please next time use the "add image" tool that is provided by the question editor, as it formats images perfectly...

Might find this link useful


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How to avoid gaps appearing in Freestyle lines?

How can I avoid these breaks when rendering outline using freestyle ?

https://drive.google.com/file/d/16dK_Q-b8PJ3QYIaJNwdPlHQp2GODaXQU/view?usp=sharing

Hello and welcome. Rather than take photos of your monitor post actual screenshots instead, see How to take a screenshot. Photos are harder to read because we have to look past external interferences (like reflections, smudges or Moiré patterns) and guess if we are looking at hardware issues such as a malfunctioning display or connections, a software level issue like driver malfunction or glitch, or actual artifacts or issues with the model itself.

Hi. Please don't post essential information like links, file downloads or additional details in the comments section where it can be easily missed. Instead edit them into your original post with the [Edit] button above. Comments are transitory by nature, are hard to index or search for, and may be erased at any moment.


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Transparent PNG image texture (logo) over BMD texture? a simple version attempt needing help
I have been trying this for 5 years failing, and although I've tried tons of different tutorials, I still seem to fail at something that should be quite simple.
I have a BMD pbr beautiful material. I want to overlay a translucent PNG texture onto it (for example a label on a  bottle as in my example).
When on material preview, the result is what I want:

But when I look at it on render view I still have this very frustrating grey background interfering:

Here's my nodes for the combo of material plus PNG:

...and I seem to not be the only one with this need! has anyone sorted this out already?
Can anyone send me to the correct youtube tutorial where this is sorted?
Can anyone tell me what to change/adjust on my nodes so that this works as I want?
THANK YOU!!!

I've added the file link into your question which should mean that it will be seen again by those in the know! - I've tried the usual trick which is to change the render engine to Eevee, change the material Settings > Blend Mode to Alpha Hash or Alpha Blend, and then change the render engine back to Cycles, but it doesn't seem to work in this case.

The acronym "BMD" is not a standard term in Blender or PBR (Physically Based Rendering) terminology. Just out of curiosity - what is it? The shader you call "BMD" is quite weird. For example it is for a metal, isn't it? But it has diffuse element and also it has fine directional noise bump that already mimics anisotropic effect, but also Anisotropic BSDF on top and weird input for roughness - it uses square root of the input, also gradient based on viewing angle, but its 50% mix with the color... None of this makes much sense... What is going on there?

Thank you again John!
Martynas: yes, the BMD acronym is the name of the texture I used, which indeed is a pbr type of texture/material. I downloaded it from somewhere can't remember exactly where from or when, but it works lovely. I did not crate it so am not exactly sure how it works and why it is built as is.
In this file the bottle is one mesh and the cilinder of "metal" where I was trying the label is another mesh as I did not want to disturb the bottle when trying different solutions
Thanks for your answer!

You should consider what this object is supposed to be in reality. It's a metal container that has a label on it. So those are 2 different materials - the brushed metal, and some sort of sticker or paint. You should be mixing materials/shaders, not colors. Also there is no reason to use "Darken" mode of Color Mix node, and you should use alpha as well to mix them.
Simple mix of 2 different materials should work:

It really should be clarified - wasn't that what they were doing? :D

Yes, but then the blend file has many mysterious things in it. Who knows what they mean?.. :D

Martynas again thank you for your reply and the nodes you shared
Will try setting that up.
Titanius: Correct-  In this file the bottle is one mesh and the cilinder of "metal" where I was trying the label is another mesh as I did not want to disturb the bottle when trying different solutions.
And yeah Martynas the file has many misterrious things in it because of my ignorance :P

Hi again
Well.. the mystery persists! I tried setting up the nodes exactly as on your solved example, and had the same result I've been getting myself stuck with.
Quite odd.
Am gonna try with a completely blank, new, nothing-in-it file, start from absolute scratch and see what happens.
But I somehow suspect the issue is in somewhere within my blender settings, as I've set up a bunch of things for renders to be quick etc... dunno. Will try and get back to you with the update.

It's frustrating, cos I have a pile of nice materials like that metallic pbr which I would like to ocassionally apply a transparent png with just a mix shader - not having to edit-redo each material... kinda defeats the purpose of having bought materials in the first place!

Latest update: cleaned up all materials in my file, and it worked. Evidently an issue with the materials I have loaded by default within my startup file. Thanks!!!


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How to make Cubic Stripes uv mapping
How can I make this striped pattern with wave texture in Blender?

I'm don't think the wave texture is the best fit.
You could however use math nodes to recreate the effect by transforming the x and y coordinates.

Thank you very much, I will try this way

The bottom left multiplys second field contains -1


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Where can I download the earliest version of blender 2.8 beta?
I need to download the earliest versions of Blender 2.8 beta because I'm trying to find the old viewport studio lighting.

https://download.blender.org/release/

Technically it is a duplicate of https://blender.stackexchange.com/questions/159168/where-can-i-download-older-versions-of-blender , but I don't think anyone keeps an archive of daily builds or betas. It is either an official release or discarded

Does this answer your question? Where can I download older versions of Blender?

you can also use Blender Launcher, its kinda like a game launcher but for Blender versions!, it  has a nice interface and supports any build https://dotbow.github.io/Blender-Launcher/

it wont let me edit my own comment for some reason, anyway, seems like Blender launcher only supports experimental builds of non released stable versions, sorry bout that


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Workbench renders quite slow
I'm cutting a project in the blender "Video Editing" tool, and I am working on my rough cut. To be able to send it and watch it outside of blender, I'd like to render it with the "Workbench" renderer.
When I simply hit play in my timeline (and make sure to clear the cache with Ctrl-R) I can watch my cut in real time, it renders immediately.
But when I render my animation with "Render -> Render Animation" it is a lot slower. It is nowhere near real-time rendering. I'd say it takes about half a second for each frame.
I've set the Sampling to "Single Pass Anti-Aliasing" for both, the Render and the Viewport settings but it didn't change much.
Is there something else I'm missing?
My viewport and the rendered version also look identical from what I can see...

I figured out that using the Workbench renderer was the wrong way to approach it. Using View -> Sequence Render Animation was what I needed.

I met the same problem, I think it's because workbench worked with CPU, but the render will ask for the GPU. However, I don't know what to do to ask for CPU when I use workbench, the only way is use the quick render in view


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Arrow rain(How can express the shaking effect when an arrow is hit?)
kill particles ver
before Kill Particle
I want to add a trembling effect when the arrow hits.
However, kill particles can stop when they are closed on an object, but they don't have a trembling effect.
3d max tuto
I want to know how to give a trembling effect while fixing like this 3DS Max tutorial.

https://blender.meta.stackexchange.com/questions/2449/what-is-the-problem-with-posting-an-image-or-link-and-asking-how-do-i-do-this

https://blenderartists.org/t/arrow-rain-how-can-express-the-shaking-effect-when-an-arrow-is-hit/1187301

Wow that would be neat to see. Breaking it down you will first have to detect when the arrow particle collides, then start the tremble. To make the tremble you can do it several ways, tremble the whole arrow and target, rig the arrow with a bone, use key shapes, or modify the transform rotation of the arrow.
I don't know what method you wish to use, but in all the animation sequence for the arrow particle needs to be triggered after the collision is detected. You can try using the "Action" constraint. If that doesn't work the only thing I can think of is a script, which will probably be only about 6 lines of code, but what code is currently beyond me. I hope the action constraint will do it for you.


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Weird Light Artifact, Render with EEVEE
I get a weird artifact when working with EEVEE, and it seems to be related to how my mesh distorts with the use of some modifiers.
I see this happening often, has anyone also see this kind of anomaly?


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Extruding without breaking edge loop
I want to model a shape with only quads.
I created a circle shape and wanted to extrude some vertices away from the curve to form a keyhole.
I am able to create the shape, but all extruded vertices are not connected to the circle shape anymore and I can´t select the Edge loop via shift-alt-LMB.
I wanted to select the keyhole in an easy way to add a bevel.

Are you trying create an extra edge loop around the keyhole to reinforce it for sub-dividing later?

No. I wanted to extrude the rectangle shape of the keyhole parallel to the outline of the cube. Deleted a few Vertices and extruded parallel to the outline with E, G, Y. But now all newly extruded veritces are disconnected from the Edge loop which was not intended.

Here is how you make a keyhole with all vertices connected.
1) Create a circle (say 32 vertices)
Stay in Edit Mode
2) Create a plane (also with 32 vertices)
Both the circle and the plane are a part of one object now.
3) Select both loops and connect them with Edge->Bridge Edge Loops
4) Almost done. All inner vertices are now connected into one loop.
5) You can now model you keyhole.
Summary: Edge loops work. It’s all quads.

Thats more or less how I created my keyhole. But instead of moving the lower 3 vertices I deleted them and extruded the rectangle shape of the keyhole out of the circle. With this all new vertices where disconnected from each other and not part of the edge loop anymore. How do you add Vertices which are part of the edge loop, or how would you select the inner shape without clicking on each of the edges?

@ThomasB Sure thing. - First, don't click on edges, but click on vertices when selecting the loop. Because you extruded your shape, there are corners, where the edge select mode will stop. - Second. If you really want to be able to select the loop in edge select mode, you need to rebuild your keyhole slightly, so that there are no corners in the loop. Compare closely my mesh with yours. My mesh doesn't have corners in the inner loop.


text:
Objects visible in camera view until click middle mouse button; not visible outside in any other view
Everything I want visible on screen:

has been unhidden
visibility has been set to show in Viewports
I did ⇧ Shift +  C and then Frame All
I have selected an object in the Outliner and turned on its name, which appears in the Viewport
I have scrolled out and in all of the way
I open the file without loading the UI to reset my mess of open UI sections
I have selected an object in the Outliner and used Frame Selected
I looked at every Viewpoint and did No. 5 above.
I have looked at the camera and have Clip Start at 0.328 ft. and End as 55000 ft. (My scene is 28,000 ft. x 20,000 ft.

Everything was working until I started rearranging the windows and adding more UI windows within Blender.
I am at my wit's end.
After all of the above, I can scroll in close and see SOME of the mesh, but as soon as I click on my MMB, it all disappears except for the names of the objects.
I can render just fine and the camera view is accurate, but as soon as I click the Middle Mouse Button, everything in the Viewport disappears.
How can I get my visuals back?
Is there some secret (or not so secret) Field of View setting I am missing?
1 - 3D Viewport scrolled in and name highlighted;

2 - 3D Viewport scrolled out slightly, tried to rotate with MMB and name highlighted;

3 - Camera view - normal;

4 - Camera view after clicking MMB.

Did you try changing the clipping value? Also, press the Numpad period . key to zoom in properly. And this is not the fault of the middle mouse button, this is your 3d view vs camera view, moving the viewport with the middle mouse button takes you out of camera view.

@YousufChaudhry~ The location of the clipping value was what I was missing. I changed that and all is well. I would like to select your comment as a solution, but I am not sure I can without your comment being made into answer.

I can make it into an answer if you want. Posted it, check.

Set the clip start value of your viewport to some low value, and the clip end to a higher value. It will fix the problem.


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Blender script keyframe in loop doesn't affect first element
Here is mine area with objects (frame 0):

I'm trying to make objects move with python script. Every object on list should move into center of my area. I'm using for loop. Unfortunately first element doesn't want to keep it's initial position on 0 frame. It looks like it is replacing 0 frame position with 20 frame position and then it works properly but it makes every move 20 frames before rest of them. I don't have idea why it is not working properly. Can you see my code and try to find out what is wrong with it?
Code below:
new_loc = [0,0,0]

frame_num = 0

for obj in creatures_names:

    ob = bpy.data.objects[obj.name]
    scene.frame_set(frame_num)
    ob.keyframe_insert(data_path='location', index = -1)

new_radius = radius - 4

while frame_num < settings['frames']:
    frame_num += 20
    for obj in creatures_names:

        ob = bpy.data.objects[obj.name]

        loc = obj.location
        x = float(loc[0])
        y = float(loc[1])
        z = float(loc[2])
        creature_angle = math.atan(y/x)
        print(creature_angle)
        new_x = new_radius * math.cos(creature_angle)
        new_y = new_radius * math.sin(creature_angle)
        new_loc[2] = z
        new_loc[0] = new_x
        new_loc[1] = new_y

        ob.location = new_loc
        ob.keyframe_insert(data_path='location', index = -1)
        frame_num = 20
        scene.frame_set(frame_num)

    new_radius -= 4

Here is frame 20:

And frame 40:

It looks like you have more than one problem:
One try using obj.keyframe_insert(data_path='location', frame=frame_num)
instead of
scene.frame_set(frame_num)
    ob.keyframe_insert(data_path='location', index = -1).
Also, you set frame_num = 20 inside your while loop... which should cause an infinite loop.
How to keyframe_insert without moving the object

frame_num = 20 should be in comment. I lost '#' while copying. But your solution works perfect for me. Thanks!

Glad I could help.

Use Vector math.
Can completely avoid any trig methods and use vector math instead.   The length of an objects location vector is its radius from the origin of its parent. In the case of no parent, the distance from (0, 0, 0)
To move it to half the distance from the origin can simply ob.location *= 0.5 no angles necessary. To do this for only x, y ob.location.xy * = 0.5.
To test made a list of all cube objects in the scene (well those with names starting with "Cube") The radius is reduced by 1 each 20 frames from 0 to 60
import bpy
context = bpy.context
scene = context.scene

cubes = [o for o in scene.objects if o.name.startswith("Cube")]

start, stop, step = 0, 61, 20 # kfs at 0, 20, 40, 60

for f in range(start, stop, step):
    for o in cubes:
        o.keyframe_insert("location", frame=f)
        radius = o.location.length
        if radius < 1e-7: #  at center
            continue
        o.location.xy *= (radius - 1) / radius

If attached to using trig, suggest using atan2(y, x)
import bpy
from math import atan2, degrees
context = bpy.context
scene = context.scene

cubes = [(o, atan2(*o.location.yx)) for o in scene.objects if o.name.startswith("Cube")]

for o, angle in cubes:
    print(o, degrees(angle))

One last thing it would appear creatures_names in question script is a list of objects not names, making for unnecessarily using obj, and ob which are the same
creature_names = ("Pig", "Goat", "Sheep")
creatures = [(name, scene.objects.get(name)) for name in creature_names]
for name, ob in creatures:
    if ob is None:
        print(f"Creature {name} is missing")
        continue

What I want to reach finally is to make creatures move randomly (random direction) but getting closer and closer to the center. I don't know how to make it move like this yet but i think vectors should be useful for me as well. Thanks!


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How to get bone location on each frame and print it 2.8
I wanted to know in each frame a specific bone location by name. The difficulty laid on getting the bone position from the pose array.

For that you have to first select the armature and the armature only
#Armature & bone names
armatureN = "Armature"
boneN = "Hand.control R"

for obj in bpy.data.objects:
    obj.select_set(False)

bpy.data.objects[armatureN].select_set(True)

Once we have the armature selected, we can loop through every frame, printing the bone position from the bones array that is in the armature's pose. We get the tail, but there are other attributes we can get from the bone.
for f in range(scene.frame_start, scene.frame_end+1):
    scene.frame_set(f)
    print("Frame " + str(f) + ": ")

    # This can be head, tail, center...
    # More info: https://docs.blender.org/api/current/bpy.types.PoseBone.html?highlight=bpy%20bone#bpy.types.PoseBone.bone
    bone = armature.pose.bones[boneN].tail

    # Since Blender 2.8 you multiply matrices with @ not with *
    bonePos = armature.matrix_world @ bone
    print(bonePos)

    #This may be useful to visualize the location that you have got
    #bpy.ops.mesh.primitive_cube_add(size = 0.1, location=bonePos)
    #armature.pose.bones[boneN]

In order to get the rotation you'll have to follow the link that is commented in the code, or you can click here

 scene.frame_set(f)

is very performance-hungry to do in the script for each frame. I'd suggest reading the data of evaluated FCurves for bones directly.
E.g. this will evaluate the FCurve Y value at frame 7. For exporting animation, you only need to evaluate keyframes.
object.animation_data.action.fcurves[1].evaluate(7)


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.collada file does not contain reference to texture
I am new to blender and I am working to create a simple plane with some texture.
For the work I do I need to export a Collada file from blender and then import it into a target software.
If I open with a text editor the .collada file from blender, I don't see any reference to the textures file I used. Therefore, my target software does not import any texture. Do you know why this is happening?

What do your shader nodes look like?

I have diffuse, bump, glossy nodes applied. All of them "come from" a different texture file (.png)

Hi is your texture in the same file as your dae file? I recently had to use dae to export from blender to sketchup and I used dae like this... I had a folder where I had my texture and blend file, I exported it to dae and dae knew that texture is in this same folder and sketchup opened it with texture loaded, do you have it in same folder?

I think I might have found the issue. You need to apply a texture through a material for the blender collada exporter to recognize it. :(
@MikoCG, my texture files are in the same folder.

This is the answer that I am talking about
https://blender.stackexchange.com/a/4900/68015

A node setup like this should export.


text:
Micro Displacement how to make it to look better, or is there a better solution (5 questions)
Recently I've been working on personal projects so I decided to give displacement map a go [I am trying to take images of wall carving, ornaments, or patterns and make it 3d, but I have so far encountered a few problems.
1.The surface is inacurate

What should have been smooth is too rough, and looks like a rocky mountain instead of a smooth sculpture
2.The original plane gemometry didn't seem to go away

I pressed subdivide in edit mode 1 time , add ten cuts
, then added a subsuf modifier pressed Adaptive, but still getting these result, and adding more loop cuts just seems to worsen the geometry and the mental state of my computer
3.Trying to figure a way to change textures
So this is the texture map and the displacement map

Since the displacement map has to be blured out in photoshop, the geometry added in isn't enough for the details, but then it seems to heavily depend on on the texture map to give details, is there a way that I can save the details and change the photo textures from stone to wood or something else? (The bump map only gives me details but since the geometry is not enough to start with without the texture map it looks horrible)
4.Is there a way I can apply the TRUE displacement, see and edit it in the edit mode?
5.Is there an another way to approach the same effect
I have watched some videos on youtube such as
https://www.youtube.com/watch?v=Tsaa_D6CcSo
I think this is hard surface modeling(not sure), though some projects can be done by this method but when it comes to wall carving, the geometry won;t be that simple, sculpting may be a solution,
but it takes time and skill to reach the decent level and look like the reference image, which is something I don't have as a programmer background lowlife freshmen peseant , and I don't know how to retropology yet.

Please keep only one question per post. Most of your issues seem to stem from lack of geometry, obviously more geometry costs more resources. You can use a Displacement Modifier instead to view live results in the viewport. Bluring the map will make you loose details

Lets go from big issues to small ones.
1.The rocky, jagged surface you're experiencing is a the fact that your displacement is too strong. Add a Math node, set it to multiply and put it between the displacement texture and the displacement output in the node editor. You can then adjust the second value to decrease the height, to make the displacement more subtle and thus convincing.
2.The original plane geometry doesn't go away, it just gets subdivided more when you hit render. What you're encountering is the preview mode - in a render preview, the mesh is subdivided less to improve performance. That is the "Dicing scale" option in the subdivision surface modifier. The smaller it is the more detailed the mesh will be - both for rendering and preview. Decrease the dicing scale if the issue persists during rendering.
3.The thing with textures is that they always add surface detail. By that I mean that certain surface imperfections are just in the Albedo, but not in the displacement. Those will dissappear if you use a different texture.  If you go too detailed with your displacement texture you'll eventually encounter the limits of whatever image format you're using. The basic displacement can stay the same, and you can slap a different texture on top without issues. Keep in mind tho that the displacement and Albedo textures tend to go hand in hand tho. Out of curiosity, why did you blur the displacement texture?
4.This feature is coming to blender, but not there yet. You can refresh the mesh by tabbing into edit mode and out again when you've made changes.
5.You can definitly sculpt such detailed wall ornaments, although sculpting is quite different. It will certainly take more time to sculpt it, a micropolygondisplacement will definitly be faster to implement. Depending on your final sculpting implementation it might be more ressource intensive as well.

Thank you! So I followed your solution and managed to fix the two problems.But the edges are still kinna weird, I assume I should add contrast to make the edge to look sharper.  I blurred the map to lose some details in order to gain more control on the final look, because if I didn't blur it, it seems that the details in the displacement map will make result look shaggy, so I blurred and added a bump map to get details back

How weird are the edges? That sounds like a curious problem, I'd love to see a screenshot of that!


text:
v2.79 - Exported .py errors
i tried to export my .py and want to upload it as addon.
the script works perfect, but when i try to import it as addon i get these errors:

It looks like you're trying to access the scene before the add-on is registered.

Possible duplicate of Accessing bpy.context gives a '_RestrictContext' warning, how to fix this?

Under the import bpy line igot directly this scene=Context.scene.     Is this wrong? Becs when i delete it my script isnt working

Yes that is wrong, if you're trying to develop an add-on. Sounds like you've written a regular Python script, not a Blender add-on

Yep, is it hard to make a script to an addon?

Hard to answer, depends on your experience with python and programming. The manual has a chapter about add-on development: https://docs.blender.org/manual/en/2.79/advanced/scripting/addon_tutorial.html If you're stuck somewhere and you don't find an existing answer to your problem just ask a new question about it.


text:
Feature Points on Mesh
I didn't start using Blender yet since I would like to know whether it's is the correct place to do my work on.
The case is as follows:
I have a mesh (XYZ- coordinates, faces) represented as Graph(the XYZ-coordinate here is the same, having edges now), and I'm trying to do the following (not sure if the process is in this hierarchical),
extract descriptors and obtain feature points(coloring them), in order to work on them as featured connected components.
I code in python, I tried to obtain Zernike moments and Fourier transform as descriptors the output is vectors, but I can't visualize these vectors on the mesh? or I wasn't able to do so, as well I need to obtain the feature points.
Is this the right place to work with?

I obtain these result for teapot object
The graph matrix is  [[0 0 0 ... 0 0 1]
 [0 0 0 ... 0 0 1]
 [0 0 0 ... 0 0 1]
 ...
 [0 0 0 ... 0 1 0]
 [0 0 0 ... 1 0 0]
 [1 1 1 ... 0 0 0]]
The zernike moments are:    [0.31830989 0.13789404 0.18738977 0.21210616 0.09979722 0.25386089
 0.16402911 0.29690689 0.26002601 0.12894862 0.07586501 0.48601007
 0.45855364 0.20280874 0.0126834  0.54532024 0.46835978 0.34243193
 0.13314587 0.09234412 0.03764165 0.159134   0.45475221 0.1222509
 0.17898168]
the fourier transorm is:  [[602.983833    +0.j          68.2650495 +308.71994353j
   68.2650495 -308.71994353j]
 [-76.48185048 +58.97442939j -41.7166658  +68.44586843j
  -65.40655281 +99.04981891j]
 [-70.793392   +31.66322377j -78.84787903  +0.77550291j
  -44.83406506  +0.51857595j]
 ...
 [-44.23448408 +10.60125082j -26.79330393 +12.57477038j
  -37.14294225 +40.98371836j]
 [-70.793392   -31.66322377j -44.83406506  -0.51857595j
  -78.84787903  -0.77550291j]
 [-76.48185048 -58.97442939j -65.40655281 -99.04981891j
  -41.7166658  -68.44586843j]]

And I would like to visualize these features on the object but what somebody told me is that I need to get the feature points and these points in which I should colorize them on the object?

The last code part in this answer allows to give vertex groups values in order to see the result https://blender.stackexchange.com/questions/146819/is-there-a-way-to-calculate-mean-curvature-of-a-triangular-mesh/147371#147371 Alternatively, you can also add vertex colors

The answer is you can do anything in blender, but you need to at least try. [ask].

The question is clear, but maybe you should indicate which kind of visualization you want for these vectors (as vectors placed at the corresponding points? As colors? others?)

@Merlin what is the problem with my question!

@lemon , the vectors I obtained is zernike moments for example, but what I did is that I make the input (the whole shape) while I'm reading know that I have to detect interest points(feature points) then for each I make descriptor extraction for all obtained interest point.Visualization is about visualizing the feature points on the shape Zernike Visualize

@RoaaSolh search and research is the first item.  Beyond this you should edit your question to include the image you have posted as a comment.

@lemon as well please if you have knowledge about this: despite the colorization ok, What I'm trying to do is to extract feature points from the descriptors(multi-scale descriptors) like Zernike moments 3d shape context etc.. do you know how the process follows? Thanks for your assist really

@Merlin Post is edited but without the image, since I'm not sure like this must be the visualization. Thanks but I really I'm trying hard in searching

Have you looked at using blender as a vizualization tool?

@RoaaSolh, have few (very few) knowledge about this, but is it to compare several meshes? (PS: except for feature points, is it ok for the colorization from the previous answer?)

@lemon yes I'm tending to get featured connected components and make matching between them, I mean match two featured connected components that refers for sure for objects.

Also please, I used to work with conda environment and PyCharm editor to install packages and write python code, could you guide me please where should I start, since, for example, I used pymesh to be able to read mesh and graph-tool to represent it as a graph. Sorry, my question may be silly, but I'm trying to learn how could I combine my work with different things.

I think you want GNU Octave (OS version of MATLAB) instead of blender.  It has a mesh function that does exactly what you want.  If not then please edit your question to include all the comments here.  The more work you put into the question the more people will read it and contribute an answer.

@Merlin Sir, may you assist me with good documentation for what I can do, I downloaded previously Octave but badly I wasn't able to find that since you know I don't have much knowledge with it. Thanks for your assist.


text:
How to model blebs like structure as in lungs alveoli?
I am a medical doctor and blender enthusiast. I am working on an animated medical lectures. I want to model these lungs alveoli. Similar to shown in illustrations below. Can someone please help figure out how to do this ?

is it supposed to be animated, like you gradually see the inside, or not?

Related https://blender.stackexchange.com/questions/14325/can-this-even-be-modeled-3d-modeling-of-flexible-spheres-in-contact-with-one-an and https://blender.stackexchange.com/questions/92271/flattening-the-intersection-of-overlapping-spheres

Would something like this work? Here is the .blend file.

Here is what I did:
1. Made 1 UV Sphere
2. Made 1 Plain Axis Empty
3. Added the following modifiers in order: Displace (Object: Empty), Solidify (Thickness 0.1 m), and Boolean (see step 5)
4. Duplicated these UV Spheres. I did separate objects, but going into edit mode and duplicating there would work as well.
5. Add the shape you want to be the cutout.
6. Select a sphere and in the Boolean modifier, set the object to your cut out object and have the operation be "Difference"
7. If doing separate objects, select the other spheres and then the sphere with the Boolean object selected last. Hit CTRL + L and link Modifiers.
Tada!
Instead of manually creating each blob, you can also make a particle system then convert the particle system to a mesh and do steps 2-7 (maybe it would work without converting to a mesh too).
If you have any questions, or I did not make quite what you are looking for, let me know.


text:
Texture baking is grabbing some textures from the wrong areas
I'm currently trying to bake my textures onto a model for exporting it to Unity3D. Lighting is set up as normal, and a joined copy of the model has been created via duplication, in the exact position as the original version.
However, it seems that during the bake process, the roof texture is being flipped with the chimney texture;
https://i.sstatic.net/sDPDT.jpg
It looks like it's almost baking the texture map that's looking down the chimney, rather than a straight flip? Following this then, the side of the chimney is displaying the roof tiling texture.
The above is with a ray distance of 1. Setting ray distance to 2 seems to magnify the effect, while setting it to 0.5 seems to make it slightly better. However, going much lower than this results in a lot of artifacting.
Would anyone have any ideas on how you can work around this?

You can add a Split Edge Modifier (for hard edges) and a Displace Modifier with a very small Strength value so that your target mesh will be slightly above your source. Now you should get a better result with a low ray distance.

If you still get artefacts on your bake you will probably need to split the chimney from the house. You can just make copies, move the chimney on both the source and target, bake, and remove the copies. The drawback is that you wont get the correct shadows.
Hope that this was helpful.

I am not very experienced with texture baking, but it sounds like your problem is due to the pieces intersecting each other when the rays are traced.
If I understand correctly, baking a texture basically creates virtual cameras a certain distance away from the mesh and renders from them, onto the object. This is only because you are trying to bake detail from one mesh to another. If the meshes are the same poly count there should be no reason to do this, so that might be an easy way to fix your problem.
However, in your case, Blender is using the face normals to determine the direction of the rays. This could be inaccurate and it can be more precise if you create a cage mesh so that it can draw a ray from the cage mesh through the vertex of the master mesh, until it hits the low poly mesh to determine where detail should be draw.
It is also possible that the UVs overlapped or were messed up when you joined objects.
Sorry that this isn't a direct answer, but I hope I gave you some ideas.


text:
Array modifier fit curve option( curve direction problem(already Ctrl+A applied, but failed to fix)
I'm trying to wall model following a path curve,
so used array modifier, and used 'Fit curve' option
problem is
the wall model does not follow the curve path while duplicating the wall object like the first image(below)
I applied scale and rotation (Ctrl +a) and the T panel's number seems not wrong.
and I checked the origin of the object and curve several times.
But I couldn't find the clue at all.
How can I fix this problem?
Thank you for your time and help in advance;

Here is my blend file

Hello. Let me just adress how well is this question written. Clear subject, with images, added tags and a blendfile attached. And a thank you in advance? I'd upvote this more times just for these things. Bra-vo!

the Array modifier with the Fit Curve won't make the object follow the curve, it will just adjust the amount of duplications so that the total length of the object is as long as the curve. To make the object follow the curve you need a Curve modifier as explained by Jachym Michal

It works better when you use the Curve modifier.
1) Go to Edit mode and rotate your mesh 90 degrees so it aligns better with the curve.
2) Set array modifier to Count or Length
3) Add a Curve Modifier and set the target to your curve.
Rotate your mesh in edit mode.

Set Array modifier to Count and add a Curve modifier

Voilà!
And here is the edited file.

I really appreciated :) Thank you for your detailed and kind explanation, it is truly helpful.

Happy to help :). You can now mark the question as answered, for others with a similar problem.


text:
Problem after using diplace modifer
I used displace modifier to give some uneven effect. and after that my modeling looks like crashed (or though, I tried to follow the instruction on utube, I might have made mistakes;)
so I searched this site. and some post says, 'remove doubles' but it still doesn't work;
Can I fix this? I even can not get a clue where this bad meshes come from;

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

Thank your for your kind offer! but..... somehow I overwrote the file;; and I made it all over again. and now problem solved ㅠㅠ...I think I might commit an elementary error.  anyway, really thank you for your time!

Your model looks choppy, too. Subdivide it more as Displace modifier needs many subdivisions to give satisfactory results.

oh, so I had it increased, now it looks better. thank for your precious time!

It seems like some of the faces of your object have normals facing inside. You can try going into edit mode, selecting everything and pressing Ctrl+N or Mesh>Normals>Recalculate Outside.


text:
Texture painting is totally messed up, resulting in lines and unpainted areas
after a few hours of hairpulling trial end error I ended up more confused than before. I am not extremely familiar with all that blender has to offer, however I decided to take the task of modelling something for my game. I am trying to make a spaceship corridor, but whenever I try to paint on the walls that are extruded from the floor plane, Blender paints weird angles and artifacts, and I have no clue what is wrong. If there is anyone who knows what causes this, help would be greatly appreciated. I even considered separately painting every part and then combining the textures, but I refuse to think that there is not an option I am missing that has to do with my issue.

Did you make UV-map?

What UV projection did you use? Did you unwrap using 'Smart Project' or just default 'Unwrap'?

First of all you should make sure that you don't have overlapping faces (select one, grab it, look at the result, Esc to cancel).
Then if you have no or some kind of autogenerated UV map, it might be possible that your wall face only has a tiny bit of space (e.g. one pixel) in the UV map. That means that Blender can not accurately calculate the color for a certain texel on that face.
You should check if it's alright by going into edit mode of your object, and opening the UV editor (separate window), then select your texture if not already and have a look at the map.

I managed to fix the issue by using the smart uv project once I finished the layout of the corridor. I am currently working on figuring out the best settings to paint the cubes and planes without them appearing to be imperfectly colored. Thanks!

Thank you, turns out my Uv maps were messed up totally.


text:
How can I stretch portion of a model along a plane/axis?
Please see image here for what I'd like to do:

I want to add stretch a portion of the part by 1mm-2mm right at the location of the plane in the image, along the Y (green) axis. This will increase the distance between the screw hole and the cylindrical portion of the part.
What is the easiest way to go about this? I've used a lot of CAD software in my time but learning Blender seems a bit more challenging. I've messed with a few things but the operation I want doesn't seem to be called what I think it'd be, or I'm just doing it wrong.
Help would be appreciated! :)

Bisect > Move > Bridge

First you have to configure Blender to work with measurements, enable snap, select increment option (if I am not mistaken enable snap is not needed but do it just in case) then select the part that you want and press G, Y, - (if you want to move it to the right, don't add a - symbol, + means right, but you don't need to place + because it's implicit - blender assumes that) then the value that you want to add (1 or 2 for example). For a more thorough explanation, see this tutorial: https://www.youtube.com/watch?v=kOxN4CHeBPQ

The markdown for keyboard keys is <kbd>G</kbd>

Please put a little more effort into your answers. Give them a little more structure by using paragraphs, learn about the  tags. Try to make use of the Shift key on your keyboard, when necessary ("I" instead of "i").

" I " in where?

@MichaelBenDavid first of all thanks for taking your time to help the community. I made another edit of your question to further improve it; keep in mind some edits could be unintentionally wrong, but edits are done in good faith to improve a question or an answer. Studying edits is a great way to improve your style, and if you want to discuss those changes, or ask what else you could improve (I think this answer is still in dire need of improvements), feel free to ask me or others on the "Render Farm" chat.

I just now see I got an excavator badge, I don't know why SE has put this thread on top yesterday :D

@MarkusvonBroady ...........................


text:
mapping using cylindrical map via script
I'm trying to create a default mapping mode for an object. I followed through understanding the python API for blender, and things are making more sense at this point, however I'm not able to create the UV map I wish on the object. Code below:
import bpy
from os import getcwd

file = getcwd()+'/data/naturalSat/models/2_Pallas_101.obj'
print("Testing")
imported_object = bpy.ops.import_scene.obj(filepath=file)
obj_object = bpy.context.selected_objects[0]
print("processing: "+obj_object.name)
#Extract the mesh and smooth all polygons
output = obj_object.data
for face in output.polygons:
    face.use_smooth = True

bpy.ops.object.mode_set(mode = 'EDIT')
bpy.ops.mesh.select_all(action='SELECT')
bpy.ops.uv.unwrap()
bpy.ops.uv.cylinder_project(direction='VIEW_ON_EQUATOR', scale_to_bounds=True)

#export
filePath = getcwd()+'/'+obj_object.name+'.obj'
bpy.ops.export_scene.obj(filepath=filePath)

Am I doing this correctly? one of the concerns I have is that the cylindrical_project arguments is direction = 'VIEW'. I'm loading a python script using the command line, so headless mode.

I am not a professional myself, but the code looks okay, I guess. Your direction isn't "view", though, but "VIEW_ON_EQUATOR", you could also use "VIEW_ON_POLES", "ALIGN_TO_OBJECT", though: see the documentation
If it's "right" or "wrong" depends a little on the shape of your objects and how you want the unwrap to be aligned to it. Maybe try out all three and see which one fits best?

They don’t change the mapping which is currently the texture mapped on every face


text:
Blender 2.8; Combine Cycles and Eevee render engines into single composite
I am wondering if it's possible to set up the following scenario:
Initiate render -> Eevee render into render layer with specified render settings -> Switch to Cycles render engine with specified render settings (specifically just a free style pass) into a render layer -> Composite using compositor alpha over
Is this currently possible? I saw some solutions for combing Blender Internal and Cycles render passes in 2.79 but I am unsure if this kind of functionality is available in 2.8
My intention is to use this as a work around until freestyle is functional in 2.8.
Thank you

What happens when you try?

This solution seems to get me 99% of what I originally asked for in the question.
Okay I got it to work, my problem was I was trying to create two different View Layers - create an additional Linked Scene instead so all your objects stay consistent between the two, in compositing make two Render Layer nodes and set each one to the respective Scenes you've rendered. Then you can alpha over the scene with the Freestyle pass and the Eevee pass.
My only problem now is that if I render both the scenes (as in neither has "Use Single Layer" clicked) it takes about 2 minutes for a very simple scene, but if I render them individually (One after another with "Render Single Layer" clicked) they each respectively take a second or two. It seems that when I render them both concurrently the Cycles pass still path traces the objects even with all the passes and ray visibility disabled. Not sure if I am missing something or if this is a possible bug.

So I'm doing something very similar, but I haven't experimented with separate scenes and concurentl renders. I found that reducing my render samples down to 1 for cycles speed up tremendously for line-only freestyle renders in cycles.
Update:
I tried your scene technique, but I haven't been able to get Eevee and Cycles to play nicely when using the Shader to RGB node.

The problem with that approach is that samples also controls the samples for the Freestyle itself, setting the samples to 1 results in aliased Freestyle lines

Can you clarify what problem you're having with Shader to RGB? I am using Shader to RGB in my scene, make sure to filter out everything except Freestyle and disable all the passes in the Freestyle scene.


text:
Free (at the time) Addon that gives 20 F-Stops to Blender Cameras
Months and months ago, I remember seeing someone from a movie company (I think) that made a Blender camera plugin aka addon for free that gave Blender's cameras as many F-Stops as the human eye.  The addon showed how there was complete reduction of blow outs in the highlights and such a better look with global illumination I was very impressed.
Now, many months later, returning to Blender after 2.79 did not do it for me migrating from C4D and Redshift (which now, may be possible, and better), this issue has arisen again.  I have e-cycles but haven't seriously learned it yet...if it's there (added as a native function) that would be as important to me as finding the plugin again.
Does ANY ONE know about this plugin?  Does anyone know if eevee, cycles or e-cycles has 20 F-Stops?  I'd be most grateful.

Sounds like you're referring to the Filmic view transform. There's an old video and blog post by BlenderGuru that vaguely matches the f-stop part that you're remembering.

Wow, that WAS the exact article I was vaguely remembering (from 2017) and the github was last committed in 2019, I'm very happy right now, tyvm.

The filmic view transform is included in Blender. It's the default in Blender 2.8x.

Ha!  Even better.  I'll start learning the nodes.


text:
Material System sometimes applies Materials, sometimes doesn't to vertex groups
I applied 3 shaders 1 for each vertex group I made.
I created the shaders in object mode first.
I went into edit mode and selected a vertex group in face mode.
I went to the materials tab and selected the material I wanted to apply.
I pressed assign.  It worked.
I saved and exited that file.  Went to the next asset. Created my materials as above.
NADA.
It worked for one geo in one file and didn't work for another geo in another file.  How is that possible?  Am I doing anything wrong?

What are you trying to achieve ?

I am trying to put basic shaders on an asset so substance painter reads them as separate texture spaces.  I literally now cannot apply any texture to even a sphere by itself.  I checked in the shader tab, and it has a shader and material output node.  I closed and reopened Blender, same behavior.  Is there some "don't allow to assign material" hotkey I don't know about and applied?  Oh holy b'jesus, I was in solid view!  Nvm...derp... sleeping is important children.


text:
How to use index and value field of particle instance modifier
I have a particle instance modifier that actes upon a cylinder and uses a hair particle system.
If I try to type anything into the Index or value field to name them for use in a shader I get an error failed to find "
How can I assinge those attributes for later use?
I already tried to create vertex groups and color attributes but nothing showed up. I am using blender version 3.4
thanks for helping.

I was also having the same problem. The solution I found is selecting "Face Corner" on the "Domain" option and "Byte Color" on the "Data Type" option when creating a vertex color attribute. I don't know why, but for me just the attributes created this way, show up into the Index and Value field.
Hope this helps!


text:
Object tracking of cable
I would like to do an object track for the front of this cable to add a dynamic hair system to it. The camera does not move, but I dont know how to get 8 trackers onto the cable tip. Is there a good workaround to get a 3d track? I am trying not to create the whole cable in 3d because it interacts with the real world.
Thanks for helping

I thought that 8 trackers was for tracking camera movement in the scene.  I've tracked an object with 4 before, I believe.

could be, I will give it a try, the documentation is a bit unclear about object tracking

There's a tutorial about object tracking here which might help.

thanks, it is kind of weird. If I already have a camera solve it does not have a problem with only 3 tracks, or if it is set to tripod. Worked surprisingly well thanks

Three points are enough. If clip is set to tripod or a camera is already solved


text:
How to make swimming pool in blender that has a dense volume of water?
I am making a project in which an object dives in a swimming pool in order to find out water depth and density. I need guidance that **

how to make swimming pool in blender that has a dense volume of
  water?

**
Any guidance in this would be so appreciating.

I'm not sure what you mean by dense? Are you looking for fluid simulation? (e.g. https://blender.stackexchange.com/q/5305/599)

Are you looking for the actual water material instructions or the whole modeling and material?

Yes, actual water material instruction.


text:
saving the animation
I have rendered and saved as pngs. I then try to save in the output area as any of the options, but they are always blender file that only open in blender, not avi,mpeg or any other. Using 2.8. Any ideas? Is there a save key or option other than this?

It's not clear what you did and what you are trying to achieve, so here is my best try:
If you want to render single image, you can press F12 (Top menu:Render>Render image). Then your image is displayed in Blender Render window. You can save this image by pressing Shift+S (Top menu: Image>Save as). Then you can choose filename and file type.
If you want to render image sequence, you have to go to output panel (usually located at bottom right of the screen (or right panel if you are using Rendering layout), its card has printer icon). Choose resolution, directory which should contain resulting files and file type (for example PNG). Then hit Ctrl+F12 (Top menu:Render>Render Animation). Images should appear in directory you choose, no other action is required.
If you want to render video file, you can do it similarly to prevous steps, but instead of choosing image type such as PNG, choose FFmpeg video and specify details in Encoding section. Again, after pressing Ctrl+F12, resulting file will show up in directory you have choosen in Output card.
If you render bigger project, it's good idea to render to images in case something breaks during render, or you realize you want to change something and re-render some images. If you want to make single video from image sequence, open new Blender file using File>New>Video Editing. Hover mouse over Video Sequencer and press Shift+A. Click Image/Sequence. Go to directory where you stored your image sequence, select all images (A) and press Add Image Strip. Choose render-resolution and frame-rate and render in a same way as I described above.
Pressing Ctrl+S (File>Save) or Shift+Ctrl+S (File>Save as) is reserved only for saving .blend file.

I think you want your animation as video that are saved in /tmp file.
As @user224348 said in his 3rd paragraph, you just have to add your images in Video Sequence Editor(VSE), this is how you can do this.
In newly opened Blender:

Click on +.

Go to Video Editing>Video Editing.

Add your rendered images: Add>Image Sequence

Locate where your rendered animation frames/images are stored(Default: C:/tmp[Windows]):
And select them by dragging cursor over your files or if you want to select all press A

You will have something like this in your timeline:

Press Spacbar to play in 2.80(2.79 has Alt+A). It will play slow at first, as it loads all images and make it a video. After first load it will play smoothly as expected.

Also set total frames(Default: 250) in Blender to how much frames or images you
  have! And this is important,... for example if your animation is shorter
  than 250 frames it will turn black at the end of the video if your frames are less than 250.

How to output:
See the panel at right, there is an option of output.
Go to Output, change fileformat from PNG to ff-mpeg video, go to encoding and change container from Matroska to MPEG-4.
Your output video file will be in /tmp you change it accordingly.

Now render animation:

After it finishes you will have your video animation in /tmp folder.
Hope this helps.
All the best!


text:
How do you change the Minor diameter of a torus in Blender 2.80?
I am trying to change the diameter of a torus in Blender 2.80.
The Blender series on this is using Blender 2.79.
How do I do this using Blender 2.80?

When you create your primitive you have a folded menu on the bottom of your 3D View, just unfold it to have access to all the parameters. Once you've made some changes, like moving or editing, you won't have access to this menu anymore though.

Confirming that once you moved it you cannot access the creation parameter, if you actually want to change later the minor radius you can simply go in edit face mode, select all the faces and then use the shrink/fatten (in the toolbar - bottom left)


text:
Simple rigging problem (or not simple at all)!
I have a problem that seemed simple to me, but whatever I've tried that turned not to be that simple.
I have 2 opposite L shapes with fixed rotation center. Their ends are connected with lever. At both ends I have two empties where first empty (Ctrl_A) affects movement of another one (Ctrl B). I'm interested only in Z location of both empties where their Z location is same as Z location of the center of the closest white circle of L shape.

So, in simple terms, I have to move Control empty A up or down and get a resulting position of control empty B like it's shown on image above.
I've tried for several hours with armature, track-to constraints, drivers, etc... and quit because I couldn't manage to get anything in place to achieve desirable result.
I'm not looking for quick complete solution, just a proper way how to make it work. I almost know nothing how armature works and all these settings are so confusing to me.

Am thinking that I might use an Armature with bone poses to accomplish this...

@james_t, That will work for sure but there's a lot of manual job. I have to control everything by just moving empty controller A up and down. I've just simplified my question, solution is part of much complex problem.

Hi. Please use a title that matches the content of the question. It should be descriptive but succinct, unique and identifying, summarizing the issue so that anyone searching for a similar problem is likely to find it. Remove anything superfluous, avoid using words like "this", "help with", "issue" or "question about", instead describe what "it" is. Remember, your title is the first thing potential visitors see, answers you get depend heavily on how insightful it is. See What is the problem of asking “How do I do this?"

So since A and B are interdependent, you can't control from both of them-- you need to pick one or the other to control.  We'll control from A.  This will determine the position of B.

"Track" tracks "A", however you'd like (I'm using a damped track, but you may prefer a locked track.)  A 2-bone IK chain inherits starting position and rotation from this tracking, reaching to the static (relative to root) Rot B.  B, our output, merely inherits the rotation of the last part of the IK chain (ik2).
Shown with a couple poses, with some simple meshes:

You may wish to lock the IK the prevent rotation in undesired axes-- as shown, past a certain point, ik1 will rotate 180 degrees about Y to maintain its bend.  But maybe you're not even rotating it that far (as shown, the lever is too long to rotate that far without discontinuity.)
B gives us the white circle (since it's not really a control.)  To get A's white circle, we can just take the position of the tail of track.  If you'd rather, you can parent a bone to Track at the location of its tail and measure the position of that bone-- a million ways to do it, just depends on what's most convenient for your purposes.

English is not my native so I might be confusing... And yes, I have to control only Ctrl A, Ctrl B is actually not a controller, it's a result. Anyway, this looks like what I need. Give me some time to try to figure out how this works.

if I understood this well... There's one armature at left L profile to control its movement and rotation with IK bone. Next armature is parented to lever and right L shape where the biggest bone is parented to lever and used to push IK bone at L profile. I don't understand what is root bone? is it just parent to them all or has another purpose here?

I put a root bone in all armatures.  Yes, it's just the parent to everything, to be able to control the space the structure exists in.

Thanx a million. This is exactly what I was looking for.


text:
Changing order of props in input dialog (addon development)
I'm creating addon that adds couple of objects to the scene and I need to control input arguments. Figured out that the best way for me (with almost zero experience with python but 25+ years in other languages, mostly object oriented) is to use existing templates. Two of them that are working perfectly are Addon Add Object and Operator Mesh Add.
I can easily define new properties by adding simple code like this
# my properties

scale: FloatProperty(
    name="Scale",
    description="some description",
    min=0.000001, max=1000,
    default=0.01,
)
clWidth: FloatProperty(
    name="Chain Link Width",
    description="some description",
    min=0.01, max=10000,
    default=12.7,
)
clCount: IntProperty(
    name="Chain Link Pairs",
    description="some description",
    min=20, max=1000,
    default=41,
)

# ... etc

What I'm getting in lower left corner of the screen is input box like this.

What's bugging me a lot are those props outside of red mark atop of dialog. Course, they are important but mostly I don't use them at all. Is there a way to switch their position and put them below my custom properties or somehow collapse them to minimize size of dialog?
I've seen some addons are using different dialogs (the way I like it) but can't figure out how to get different look.
This is an example

Even if there's a way to remove those transform props completely, will be fine because I'm rarely using them and mostly doing all transforms later directly on the scene.
Any suggestions?

I'm sure this has been answered before but can't find it. Please look draw method in the docs https://docs.blender.org/api/current/bpy.types.Operator.html#custom-drawing. I think you also have the option to hide individual properties when defining them with the options = {"HIDDEN"} argument https://docs.blender.org/api/current/bpy.props.html?highlight=bpy%20props%20floatproperty#bpy.props.FloatProperty

@Gorgious I've been looking for answer here and around the web but couldn't find anything that I can use to solve it, even a hint. Problem is that those properties are not defined by me so I can't find a way to hide them. Guess they are defined in parent class somewhere else and inherited here. Thanx anyway, I'll take another look in official docs to see if there's something usable.

If you use the draw  method you'll be able to "whitelist" the props you want to display, any prop not specifically part of the draw method will not be displayed

You can use options = {"HIDDEN"} to prevent props from being displayed in the default operator layout redo panel.
https://docs.blender.org/api/current/bpy.props.html?highlight=bpy%20props%20floatproperty#bpy.props.FloatProperty
import bpy

class SimpleOperator(bpy.types.Operator):
    bl_idname = "object.simple_operator"
    bl_label = "Simple Object Operator"
    bl_options = {"REGISTER", "UNDO"}

    hide_me: bpy.props.IntProperty(options={"HIDDEN"})
    show_me: bpy.props.IntProperty()
    show_me_too: bpy.props.IntProperty()

    def execute(self, context):
        print("done")
        return {'FINISHED'}

if __name__ == "__main__":
    bpy.utils.register_class(SimpleOperator)

Alternatively you can "whitelist" props to be displayed and choose how they will be displayed in the draw method. By default the draw method will display all props that do not have the "HIDDEN" option.
https://docs.blender.org/api/current/bpy.types.Operator.html#custom-drawing
import bpy

class SimpleOperator(bpy.types.Operator):
    bl_idname = "object.simple_operator"
    bl_label = "Simple Object Operator"
    bl_options = {"REGISTER", "UNDO"}

    hide_me: bpy.props.IntProperty(options={"HIDDEN"})
    hide_me_too: bpy.props.IntProperty()
    show_me: bpy.props.IntProperty()
    show_me_too: bpy.props.IntProperty()

    def execute(self, context):
        print("done")
        return {'FINISHED'}

    def draw(self, context):
        row = self.layout.row(align=True)
        row.prop(self, "show_me", text="SHOW ME !!")
        row.prop(self, "show_me_too", text="SHOW ME TOO !!")
        self.layout.prop(self, "show_me", text="or show me like that")

if __name__ == "__main__":
    bpy.utils.register_class(SimpleOperator)

Yeah, that's exactly what I was looking for. Thanx a million mate.

Happy to help ! Cheers


text:
Problems with Transparency when rendering with Volumetric shaders
When I render it in viewport then it looks normal:

For the fire, I just youse a normal Principled Volum shader that is plugged into Volume of the material Output. I render with two layers one for the fire and one for the ground. In the fire layer, the ground collection are contributing with Indirect Only and for the ground layer it is the same but here the fire collection is contributing with Indirect Only
My problem now is when I render end export each layer on their own then the fire looks weird:

And when I want to combine them later in gimp everything is messed up:

but in the blender Compositor with the alpha over node only thos parts of the fire without a background are messed up:

In Blender in only turned the transparent mode on and turend the Sample count to 256 for the renders.

The render viewer is broken. Read: read: https://blender.stackexchange.com/questions/57816/how-do-i-get-the-glare-node-to-output-transparent-instead-of-black-background/57824#57824

Okay, thank you. The problem seems to only accure when I set the Mantaflow emitters to Fire  when i set them to Fire + Smoke everyting is normal.

As stated in one of the comments is this a problem of blenders internal way of handling unoccluding emissions. See the comment from @susu for details.


text:
Specifically control IK behaviour
I tryed to rig the landing legs of a spaceship. So I can animate them retracting.
But when I try to retract them the IK bends the objects into the spaceship, instead of bending them up. Is there a way to "teach" the IKs to behave how I want them to?
Here you can see the IK picking torugh the leg the blue marking is how it should behave.

In such easy IK chains (2 bones), it means that it is physically impossible. With given lengths, it shall behave like this.
So you should make the top part a little shorter / bottom part a bit longer.

Thank you yup I was dump dump


text:
Compositor Blows out Image
I am exporting into half EXR's with ACES_cg (would full help?)

But as you see in the second image the compositor output is blown out. But when I take a look at the EXR it is not blown out but still does not go over 1 why?

Can anybody explain to me why and how to fix it or is it just a limitation of Blender? And Thank you
Here are my Color managment settings:

This is my fault I messed up the compositing the denoise node was not set to HDR and flattened everything


text:
UV unwrap proportions aren't consistent with model
So I've applied Rotation and Scale to my model in object mode and when I unwrap in edit mode, some sections aren't holding the correct proportions. In the picture you can see what I'm talking about. I'm making a stadium and so the risers are a smaller dimension than the step. On some sections, it unwraps correctly but on others, the steps and risers appear to be the same size.
Is there anything that could be effecting this?

What ended up fixing the issue for me was to go to the Unwrap operation panel and switch it to Conformal instead of Angle.


text:
Simple Rotation problem
I am almost embarassed to ask something so simpe, but can someone give me a pointer as to how to rotate a surface 45 degrees without the distortion and maintaining dimensions. See attached.
Thanks
Richard C

Duplicate question: https://blender.stackexchange.com/questions/68591/rotate-without-distorting-size Includes GIFs! ;-)

Duarte's right, the question is well covered in his reference.. In my answer, I've tried to describe the 'Cut' option better ..

The answer is: it's not a rotation.  If you visualize the circular rails around which the vertices would travel in a rotation, you can see that.
If you wanted a transform to do the job, on parallel rails, it would be a shear. (ShiftCtrlAltS). But that's expressed in terms of offset, which would be half the length of the vertical edge to get 45 degrees, and would be awkward.
So the best idea here is probably a cut. Hit K and left-click on your starting vertex. It should highlight green. Hit C to snap the cut to 45 degrees, (and Z if you need to cut through more than one layer of faces), and move the mouse over to the opposite edge, until you see the highlight again. Left-click to 'plant' the other end of the cut, and the Space bar to confirm it.

I think it may be beneficial to add images to illustrate some of your points.

@RayMairlot   Wilko.. but I can't get to that for a while..

Why not just scale to 0 on an axis: S X 0 ?

Other options :
Flip the extrude edge along the X axis :

Or move the pivot point (center of rotation) to the lower of the 2 vertices of the extruded edge and rotate about that :


text:
Similate a vessel being filled with a liquid
I would appreciate some help with the following:
I am trying to animate filling a non-uniform shaped mesh with a liquid. I do not want to use a fluid modifier. The end result I need is just a graphical simulation for a web page.

As you can see the vessel is an 'odd shape'
Any pointers towards a solution would be appreciated.
Thanks
Richard C

Would this help? - https://blender.stackexchange.com/questions/143307/how-to-fake-fluid-in-a-jar-while-moving-jar-around

If you just want to raise the liqud level, you can have the inner shape with a volumetric material sat up as water and then make a cube and add wave modifier to it. Then add a boolean modifier to ineract with the inner shape of the Vessel. Then animate the cube to rise up in Z direction. (The inner shape of the vessel must be seperated object from the vessel) Also I suggest to retopology the mesh, it seems that there are some n-gons in your mesh that are causing some shadowing problems or could be wrong sided normals...

Thanks Edge3D - the link is very useful information and solution for a different issue I will face later in the project.
Mohammadreza - many thanks - your suggested workflow is a perfect solution for this problem

No problem! @Richard


text:
Timeline frame advance in Action Recorder
I am using the Action recorder add-on. I am copying and pasting a pose. In between copy and paste I want to advance the timeline by just one frame, usually achieved by using the right arrow key. Action recorder doesn't pick see this keyboard action.
Anyone have any ideas how else I can get action recorder to recognise how to move the time line marker by one frame in the middle of a macro
Many thanks
RiChap

That appears to be a third-party addon which is not supplied with Blender so you should ask the addon author.


text:
B&W Opacity map
How do I use a black and white opacity map like this one in Blender Cycles? I have searched and tried everything I have found and cannot get it to work.

Possible duplicate of How do I get transparency to work with the Principled BSDF shader?

Here is a screen shot of how I use images like this. I plug the image into the mix factor between a transparency shader and a diffuse or emission shader (whatever you want it to be) and then where it is white, you will see the solid, black is transparent.


text:
Having Problems With Metal Material
I am trying to apply [this] material

(https://www.poliigon.com/texture/metal-spotty-discoloration-001)
to a rectangle by using this tutorial.
But when I tried to to put the respective materials into blender, it ended up looking like chocolate mess.

https://i.sstatic.net/WxBbk.jpg
For reference, I unwrapped the object, than I applied all of the materials as per the video, since the materials were set up the same way. Any help?

What does it look like outside of edit mode when it isn't highlighted orange? Also you may want to check your scene lighting. Particularly with reflective materials, lighting plays a bit part in how they look.

perhaps share your file with packed images textures, or at least show a screenshot of your node editor

Check if you have applied Image Texture not to Diffuse Material but Glossy BSDF. If its Glossy BSDF that it is correct.

Ah, it appears I just used the wrong materials for each part.


text:
How to add a single image to a cylinder
I want to know how to apply a single image, like so
,
to a primitive cylinder. I tried using the node editor with this chain:
Texture Coordinate - Mapping - Image texture - diffuse - output
but I don't think it works at all.
Any help?

Are you trying to apply it in top and bottom faces, whole cylinder with top and bottom faces or only the body?

have you unwrapped your cylinder?


text:
How to reduce repetition of textures

Im currently trying to add a texture to this model that should look something like this.
How would I go about reducing the number of repeating textures. I know that each texture is bound to a face right now, but I can't reduce the number of faces or else it will no longer be sphere like.
Thanks

From your screenshot you have your Vector input of the texture set to Default - this will be using a UV Map to orient the textures on your faces. In order to maps your texture over the whole mesh you either need to change the UV map (search for online tutorials for UV Unwrapping - it can be quite a simple or complicated process, depending on your needs and situation) or switch to a Vector setting that does not use your UV map - such as Generated.
I your case, Generated would seem to be the best option since you want the texture projected over the whole mesh from above - so change Vector to Generated. However, I also note from your screenshot that you have your Mapping set to 'Normal' - this can produce unexpected results (I presume this was the result of you trying to adjust your mapping) - so change it to Texture. You should then adjust the Scale and Rotation to orient the image on the mesh how you desire.