text:
Why is my model not loading correctly?
I attempted to make a simple cup for use in Tabletop Simulator.
When I load the .obj into the game, my model is missing an entire face (The bottom).

https://i.sstatic.net/5YtEB.png
However I've uploaded the obj to the A360 viewer by Autodesk and it looks fine.
https://a360.autodesk.com/viewer/id/dXJuOmFkc2sub2JqZWN0czpvcy5vYmplY3Q6YTM2MHZpZXdlci90MTQ1OTIzMDk3MTkzMV8wOTc0NTM0Njk5NTExNjM1MS5vYmo%3D?designtype=obj
I just started using Blender today so theres a good chance I made a simple mistake.

Here is the .blend in case someone wants to see what I messed up.
http://hnng.moe/f/9ha

The bottom faces are Ngons. Probably your game engine doesn't handle with them correctly, hence ignoring it. Try deleting it and converting into tris / quads (or convert to tris while exporting but this isn't the best way as you won't be able to control the conversion).

The face is there but it faces the wrong direction. The autodesk viewer probably ignores the face normal and shows it on both sides.
What you have to do is to flip the normal of this face.
you can read more about this issue here:
How to make all faces flip to the right/consistent direction?

Thanks for your response! I'll go ahead and read that article and try again.


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Best way to model this mushroom
I have already modeled the mushroom but i'm not sure how best to approach the grooves at the top of the mushroom.

I guess displacement would be the best option here, did you unwrap the object?

Not yet. Figured i would finish the modelling first. I have tried displacement didn't like the results.

If it's for a game, a texture would be necessary as making the mushroom would require too many faces, slightly laggy. Personally, i'd use textures even if it isn't a game.

When modeling is done you rather need materials than more details, in this case an x-scaled muscrave texture as bump mixed with a translucent material.

I would probably just sculpt that detail in sculpt mode with dyntopo enabled and detail size set to 3 - 5. I'd probably make the hat of the mushroom a separate object in order not to mess up the nice topology of the rest of the model. Also, if you keep a copy of the hat as it is now, you could then later use the high-res sculpted hat to bake displacement and/or normal maps to the low-res hat, if you're concerned about performance or render times for your final scene.

source: Stack Exchange

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

sort: votes


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Bezier curve taper on independent axes?
In the simplified example below I have a straight bezier curve with a bezier circle specified as its bevel object to give a cylinder. I've added a taper object to vary the cylinder's width along its length.

I would really like the taper to vary independently across the horizontal and vertical axes, like this:

This doesn't seem to be possible since there's only one Taper object option, and no way to lock it to an axis as there is with the Simple Deform modifier. What would be the best way to do this? I suspect I would have to convert the object to a mesh and then scale by hand with proportional editing, but I'd really like to continue using curves because it'll be easier to get things accurate. Might this be possible, or are there other ways this could be done?

You could use a Lattice, it works with bezier, but is it the kind of tool you want to use or are you trying to find a 100% bezier solution?

Ah yes, that should do the job and give me the fine control I'm looking for. Being able to apply the lattice to the curves will give me the best of both worlds. If you make this an Answer I'll give you some StackExchange points :)

can also use bones and scale them to have the taper effect.

@ lemon, could you please tell a bit more?

You could use a Lattice modifier, it works fine with beveled bezier (just keep in mind that when you create your lattice, adapt its size to the object in Object mode, not in Edit mode):

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


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How do I get my file to export as a .stl?
I can't export my object as an .stl.  I started with a UV Sphere and I used a boolean modifier on it and joined other objects to it. I removed doubles, re-calculated normals, tried triangulation, selected the object when exporting. Nothing works and the .stl file is empty. I also uploaded it to https://netfabb.azurewebsites.net/ and it was rejected. Any suggestions?

Pretty vague and hard to help with provided information. Give us some more info, post some images of your model or screenshots of your modifier stack or ideally post your Blend file if possible.

what happens if you export the default cube of the startup scene?

I'm a novice just starting last week on it, so sorry for being vague.

I uploaded the file here:

The Local View is enabled for this object in your file.

Local view isolates the selected object or objects, so that they are the only ones visible in the viewport.

manual page
Press NumpadSlash to exit it, select the object and try exporting again.
A side note:
- although you recalculated normals some of them are still inverted (the bottom);
- the topology of the mesh is a bit off, especially on the bottom, which can cause unexpected results when triangulated.
- scale of the mesh isn't applied (which can also be undesired);
However, this doesn't affect your current problem directly.

I know I got a long way to go and I'll have to read up on your comments.  I'm on a Mac so not sure what the NumpadSlash equivalent is so I'll look that up too. Thanks for taking a look. You guys are great.

@Zowee see this, could be useful. In general you can remap shortcuts to new ones in order to use them as desired. As for my recommendations, the only thing that should be done is exiting from the Local View. The last paragraph doesn't affect this and was mentioned only for completeness.

Try this: Create a new default start-up Blender file. Append your sphere from your original file into this new Blender file. When it is appended (so you can see it in your new Blender scene), select it and export it as an stl. Does that  work for you?  It did for me... this is what I get:
EDIT:
Sorry... wrong link:
https://www.dropbox.com/s/cxiyub2pu6i10c3/untitled.stl?dl=0
END EDIT
Let me know...
If you need info on appending: https://www.blender.org/manual/data_system/linked_libraries.html

This seemed to work as the file size seems normal. Thanks!

Thanks... and see Mr Zak's answer below for some notes on the mesh... and esp. applying scale. Out of curiosity, what are you printing it on? We're getting a new Form 2 in a couple of weeks... and like using Blender for STLs. If you have a copy of ZBrush, it's really handy for hollowing out shells, however.. it's something that ZB does a little better than Blender...

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


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Shattering a bottle with bullet
what would the best and easiest way be to shatter three bottles. I tried cell fracture but the vertices just mix and create this weird vertices blob.
I am trying to shatter it with a bullet but if I can't create the shatter portion I am not sure how I will complete this model. Any links would be much appreciated.

Fracture modifier is the way to go. You need the extra vertices to define the mesh. You really should watch a tutorial on this, as I think this is way outside the scope of this site. If you have a specific issue, feel free to post it though.

Thank you for the response I will go ahead and try that.

@NᴏᴠɪᴄᴇIɴDɪsɢᴜɪsᴇ your solution was right on target thank you!

I was playing with the model after appending to a different project a couple of times and it occurred to me how silly I was being.  I had it set to be visible on frame 1 but on frame 50 it became invisible then on frame 51 I had set it back to become visible on accident. :P I am a silly rabbit sometimes.


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How do I set up a 3rd person character with multiple animations in the Game Engine?
I am using the Blender Game Engine to make a 3rd person game. I want the main character to have separate armatures/animations for the upper body and the lower body. For example I'd want my character to be able to jump, crouch, and run while shooting and aiming a gun. I have tried to make two armature modifiers but only my leg armature deforms my mesh.

Just use only one armature for your character.
Create your two different actions on the same armature. Make sure that no bone is used in different actions at the same time. (In your case: action one -> exclusively the upper body part, action two -> only bones of the lower half)
Last thing you have to do, is to select different Action-Layers for your actions in each action-actuator.


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What will happen with Blender 2.8 game engine?
Blender has just purged the entire game engine from 2.8. There is no "Game Engine" mode anymore and there isn't even a logic editor. I tried installing a GitHub Blender release with the game engine mode working but it failed to install because all the game code was gutted. Does this mean that Blender 2.8 is going to lose the game engine, or is the game engine just being redone for better compatibility and whatnot?

The first two sentences of your question answers your question.

As far as we know the Blender Game engine has been removed from official Blender releases for good, at least in its old form. As of commit 159806140fd3 - Removing Blender Game Engine from Blender 2.8 on April 2018, BGE is no more, along with other "ageing" components like the Blender Internal Render Engine viewport drawing code among others.
Ton Roosendaal himself was given the honour of making the commit that put the old code to rest.

As for the reasons for removal we can conclude it was an old and ageing component, it was largely unmaintained, suffered from several bugs and limitations, and the Blender Foundation probably lacked the energy, motivation and manpower to maintain it properly.

Adding new things to Blender gets much easier that way. The Blender
Internal code started in early 90s. Over 25 years old! Functionally,
EEVEE can (and will) completely replace it.
Ton Roosendaal

It was also very architecturally outdated, lagged severely behind the current industry standards and modern technologies in many ways, it would be very hard to bring it up to date. Modernizing it or introducing new features would end up being more work than a full rewrite from scratch.
For that reason they decided to release Blender from these "metaphorical shackles" holding it back; making it easier to move forward and update other more important and frequently used features.
This frees Blender developers to work on other things, allowing more manpower to be redirected to truly useful new features like a better viewport drawing code, a modern layer system, a better dependency graph, usability improvements, among others. These will instead help you produce better game assets (which is Blender's main focus, and where its greatest strength lies anyway), rather than trying to run the game itself, leaving that role to dedicated engines.
"Why won't they make a new one then?"
Probably both because "we are too late to the race" and it would be a tremendous amount of work to write one well. There are already a number of well established third party game engine solutions out there, both free, open source, or commercial; and competing with those would be extremely hard and pointless.
Writing a full game engine is no small task, it is a full time job on its own, and maintaining it well would require a lot of continued manpower and resources. Since expectations are very high (supporting multitude of hardware and environments, multi-platform publishing, modern physics, logic systems, networking, security, smooth performance, and all the modern commodities expected of contemporary game engines) it would probably always end up feeling inferior or lacking in lots of ways compared to more mature established competitors.
What About Forking It?
UPBGE is a third party fork, whose objective is updating and modernizing the BGE with better technologies and features, with the end goal of eventually merging it back with main Blender development branch.
I fear its future is uncertain at this point unfortunately. While I believe Blender developers won't actively do anything to purposefully break Blender trunk codebase compatibility, I speculate it will naturally become increasingly hard for UPBGE developers to maintain their code working, as features are removed and main Blender development deviates further from the current design.
UPBGE will probably continue to work as standalone based against current 2.79 versions for any foreseeable future, but you will likely miss all the other improvements made in subsequent versions.
While the final decision is always yours, as it stands your time is probably best spent learning something else more ubiquitous and modern, giving you a more lasting and future proof investment.
So, is it really gone for good?
In its current form yes.
There have been talks about replacing the old game engine with a newer better integrated "Interactive Mode". It would be a more integral part of Blender, as opposed to a separate component with a lot of duplicated code that re-implemented a very limited subset of supported features we currently have.
This is not meant to be a direct replacement of the old BGE, nor a discrete game engine in the traditional sense with wide publishing capabilities, rather more of an integrated real-time "presentation tool" or interaction mode with a physics simulation sandbox environment, that runs directly inside Blender's viewport on currently supported platforms.
On 28 May 2018 Ton Roosendaal announced in the Developers Mailing list that a portion of the 2.8 Code Quest funds was reserved for the development of a new and improved real time rendering system or "Interactive Mode" and Benoit Bolsee, a developer historically known for his involvement in real time side of Blender, accepted a grant to work part time on this for one year.
I speculate this will probably feature a new node based workflow and logic system,  real time physics, and integrate well with other upcoming features like "Object Nodes" also known as "Everything Nodes" in one way or another.
When will it be ready?
A project of this magnitude requires a lot of careful planing and design to get done right, this will lay solid foundations on which to work on. On top of that there is still the huge amount of work required to actually implement it and get it working, tested and stable enough for the general public.
This would take a dedicated team working full time a long time to get done, it will take even more for a single person to do it alone.
Since Benoit is only working on it part time and for a relatively short period of one year, this is likely still very far away in the horizon.
As of 2020 development seems to be indefinitely on standby, probably waiting on  solid planning, development of required dependencies and maturing of current features. There are currently no predictions of when or if it will ever be resumed.
If you would like to help and can't code, you can contribute to the Development Fund. This will allow hiring more full time developers to work on newer features. Have in mind that there is no guarantee this will specifically direct funds dedicated to Interaction Mode, but they might get there faster. And if there is enough interest maybe a full time developer slots can be allocated for these tasks.
So what do I do now?
Though BGE is going away for future versions nothing stops you from continuing using it under Blender 2.79 or UPBGE for the foreseeable future, as long as they work in current hardware and operating systems.
If you are spending time and resources learning the craft, you might as well invest it on something popular and well accepted in the industry, with a bigger audience and wider reach. Learning resources will likely be more abundant, and it might even increase your future employability, if you seek to work in the industry.
There are many third party game engines out there, good for many different purposes and workflows, and for varying "wallet sizes". Some integrate very well with Blender, even using its native UI (like the Node Editor through PyNodes) for editing a varying subset of supported features and functionality.
They also provide extended publishing capabilities, reaching many platforms never before supported by Blender Game Engine (like mobile devices, web, cross platform development, among others).
The best known and most well established ones are probably:

Unreal Engine
Unity
Uniengine - Focus on real time presentations for industry and enterprises
CryEngine
Lumberyard - Amazon's Open Source version of the CryEngine Discontinued and replaced by O3DE
O3DE Lumberyard’s Apache-licensed successor.

There are also free and open source solutions that integrate very well into Blender pipeline and native UI like:

Godot - Well established free alternative, 2D graphics focus, popular for mobile content.
Armory 3D - Relatively young entry, actively maintained, free and open source license.
Urho3D - As pointed out by user Kabu in the comments
Ogre 3D -  One of the oldest open source engines around, since 2001

While not a game engines per-se, products like Blend4Web and Verge3D provide Blender addons for web publishing that also have some form of node-based logic systems and scripting capabilities. These allow creation of basic behaviours, and a certain degrees of interactivity, thus providing a simplistic yet relatively capable web browser based game creation solution.

This makes me sad. I’ve made every one of my games with BGE and to lose that feature is like losing Blender. I thought for sure they would update the game engine since they have a PBR game engine renderer in the works. If they can’t give me my game engine, EEVEE better make up for it in a massive way! I hope that my friends at UPBGE can figure out a way of getting the game engine back into Blender 2.8!!!

Have in mind that EEVEE is not a game engine, it is just a real time viewport rendering solution

Yes, but with it’s awesome features, it would make the most kick-ass game engine ever!

@CadenMitchell you can still continue to use BGE through Blender 2.79. The thing is though, it hasn't been really updated in a really long time and its features were already over 10-15 years behind current tech. What you have learned and can do on BGE will translate well to other engines, don't be afraid to try.

Remember, the BGE is not gone. It is still there. Nothing stops you to use it now or in future. Blender 2.79 is still a complete editor for assets and logic.So you do not loose anything regarding the BGE.

I added Armory3D and Urho3D to the Wikipedia list of game engines (https://en.wikipedia.org/wiki/List_of_game_engines). You may find other interesting open source game engines like Panda3D or Irrlicht but I am not sure if they have a good web and mobile export compared to others like Godot.

By the way, my Wikipedia contributions for Armory3D and Urho3D have been censored 2 times for the reason "not a notable game engine": https://en.wikipedia.org/w/index.php?title=List_of_game_engines&type=revision&diff=854600282&oldid=854586804 https://en.wikipedia.org/w/index.php?title=List_of_game_engines&oldid=prev&diff=855043321
It is not the first time I see this kind of censorship on Wikipedia... If some of you are using Armory3D and Urho3D, I suggest that you create dedicated Wikipedia articles explaining the features so they can then be accepted in the list of game engines.

My 2c worth as a python dabbler, is bpy and bge diverged at the advent of 2.5. My first look at blender was around 2.2... wrote first addon for 2.49.  I have dabbled somewhat in  bge (don't all programmers want to write a game?) but not having the grounding in < 2.5 it always felt a bit retrogressive.  Can hardly  wait to see how the interactive mode progresses.

Good news! Blender 2.8's Interactive Mode is in active development already!
Here's what happened in the recent past that led to this:
On Sep 24th 2018 Brecht sent out an email to Blender mailing list and said:

... Benoit visited the Blender Insitute last week to talk about
  interactive mode design. The plan is to first implement an interactive
  "physics sandbox" mode, where physics keeps running while you interact
  with objects the viewport. The second step then is implementing a
  logic nodes system. Benoit and Jacques will work on the design.

On Oct 5th 2018 Ton sent out an email to the Blender mailing list and wrote:

... Most notable is support for Benoit to work on the design and
  foundations for the new real-time / interaction mode in Blender. He is
  currently working on a design doc which will be presented in our
  channels soon.
  ...

As of Oct 11th 2018 Benoit has created a new branch, called interactive_physics, off of Bender 2.8 branch for development of the interactive mode. I have also been exchanging some emails with him and here is his current plan, subject to change:

... I have indeed started a project to bring interactive mode in blender
  2.8 to a point where it can be used for game prototyping, interactive simulations, robotics, etc. It's a one year project but I'm only
  working 1.5 day a week because I have other projects on the side. The
  project plan is as follow:

bring 'continued physics' mode back : physics simulation runs even if scene frame is not incrementing - done already for rigid body
bring local time to animations so that animations can run independently of scene frame
create an internal event system to exchange events and messages between scene entities
create events from physics simulation and interaction
create a logic node tree system to allow game logic (Points 3-5 will be done in collaboration with Jacques Luke who has been hired to
  create a real-time nodal logic framework in blender 2.8)

There is no guarantee that this interactive framework will be real
  time but it should be close to it. The graphic rendering will be
  Eevee. Everything will run from the 3D view, which can be customized
  to be just a window frame (or full screen) with no menus and buttons
  so that it looks like a game window. ...

A couple of months ago I also proposed my ideas regarding Blender's Interactive Mode here. I have been in touch with Ton and both developers of the interactive mode and I am so happy that they are very open to new ideas. Based on my latest discussions with Benoit the very next updates of the interactive_physics branch will include new version of Bullet physics engine for better performance. He will post the updates regarding the interactive mode here hopefully every week.
People involved in developing the interactive mode are seriously thinking about bringing very good, near-real-time or real-time soft body physics in the interactive mode in addition to rigid body physics. There are currently a couple of options that we are evaluating. Bullet's soft body solver is a pretty bad approximation of real-world physics and is unrealistic and unstable; so this option is out. One option is implementing some of the works that are coming out of research labs and are based on Projective Dynamics Method as discussed here. These methods will benefit the interactive mode with better performance and a little bit more realism in terms of physics simulation compared to real-world soft body physics. Another good thing about these methods is that they unify cloth and soft bodies.
Another option for bringing real-time soft body solvers to the interactive mode (and Blender in general) is to implement a very the method proposed here just a couple of days ago. The advantage of this specific method is that it is definitely real-time and even faster that the GPU-based solver used in NVIDIA's FleX. Another very important advantage of it is that it is differentiable! It also seems to be more accurate and closer to real-world physics. In addition, it might be possible that this method will provide a unified framework for simulating rigid body, soft body, cloth and fluids (liquid or gas)! I am going to meet with the author of this paper to learn more about the limitations of their method and seek the possibility of integrating their CUDA code into Blender very quickly.
Anyhow, I'm certain that the interactive mode of Blender 2.8 will be a game changer and truly awesome! It will integrate lots of features in one place and make lives easier!

There is a new Engine planed (last weekend 28-5-2018) it will be more then we had. Node based logic, with plans to have that exportable to other engines.
This time it gets serious...
I think since there is now eevee and since development is still early this opens a lot of possibilities wich wasnt possible before.

Could you provide a link to a source on the new game engine? That sounds interesting.

The development grant had just last sunday been granted to make 1 year grant for 2,5 hours p week..
i think 2.8 needs to be more ready before viewing the code would be usefull. (2.8 is quite unstable at the moment), but that will change after their first internal projects), width luck perhaps aug or sept a first beta of 2.8 (i hope) and then i suspect game engine development can start  (i assume that first animation needs to be implemented fully first).. As they have learned their lessons from 2.79 and will not use "double" everything to make things work in game engine and in normal mode.

I'll keep my ears open, thank you. It's always good news when another reasonable competitor shows up on the game engine market.

latest info though tells about Blender beeing more open to other engines, ea Armory engine plugable into Blender.
Not sure how it will turn out, though Armory seams quite ahead of the proposal, curious how it will end.

@MichaelEricOberlin here are some links: https://twitter.com/blender_org/status/1001110824012967936 https://lists.blender.org/pipermail/bf-committers/2018-May/049438.html

So i thought it was rumored that armory 3d is very close to becoming part of the new plans to optionally blend into blender, ea suporting the new design of blender 2.8 in such a way that new game engines should be able to plugin but not be part of blender itself, just like a render engine (luxcore and others.

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


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How do I motion track a person and control an armature?
I am working on an animation series with fight scenes. Animating everything by hand takes a lot of time and doesn’t always look good. I was wondering if I could motion track a person with various markers and transfer the movement to a rigged character. Then movements would be smooth and realistic. Can I do this only using Blender or do I need special equipment and software? ;)

Check out the camera tracking capability. The tutorials (e.g. from Blender Guru) use it to track camera motion, but you could try and attach your rig to the tracked objects.
Haven't tried it myself.


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Why am I getting a jagged brush when sculpting with dynotopo?
I've created a simple mesh consisting of a cube that has been modelled out into a corner by extrusion:

I'm now trying to sculpt detail onto it in sculpt mode using dynotopo, however I'm getting different results on different sides of the mesh.
The bottom of the mesh (which was the original cube that I extruded from) sculpts nice and smoothly as expected, however the other side is jagged and distorted which I can't sculpt as nicely. Why is this? The original faces appear to be the same.

You didn't apply scale to your object

@DuarteFarrajotaRamos This should be an answer.

An answer it is :)

You probably didn't apply scale to your object.
In Object Mode with your object selected press Ctrl+A > Apply > Scale

That's exactly it - could you explain why I need to do this?

Probably a limitation of the current system. Your object appears short, but is in fact tall and squished down. This causes issues while trying to paint on it, Blender brush can't read its true dimensions causing artifacts as it compensates for scale, that results in squished down strokes.


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Imported Obj and MTL files do not display correctly
I am a bit of a noob at blender.
I have an Obj file and a Mtl file, which Windows' default model viewer can put the two together with no issue, so I know they're linked.
When I import the Obj file, they both import in the list, but the model appears black with 0 light source, and white with one. I've tried fiddling with the diffuse, but no avail. The block-white colour does change if I change the light source.
I've done my best to try and sort the issue by looking at the forums, but now I've come unstuck despite my best efforts.

Possible duplicate of .fbx export why there are no materials or textures?

The thing is, reading this post doesn't help either. I just simply want to see the material to show on the model, so I can bake it and turn it into a UV map. But I can't get it to show, so I can't proceed.

Without knowing more about your model, bottom line is that you have to create new materials using the provided textures targeting your desired render engine

Is this in cycles or blender internal?

If you're importing MTLs for your OBJs you need to make sure both the MTL and supporting UV texture JPGs/PNGs are selected during upload
Otherwise your model will be missing textures ,
 another noob here , just read this in a chat though, hope it helps


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What is the best way to procedurally texture an object without the hard edged seams I am getting?
I have a simple image I made which can be tiled to produce a relatively nice texture. I followed some tutorials with chainmail and using the blend function it looks nice, but for other textures I cannot blend them. My nodes are set up for Texture Coordinates -> Vector Transform -> Mapping -> Image Texture (set to Box, which is what gives the best result but has hard edges) -> Principled -> Material output.
Is there a way to made it seamlessly wrap around a complex mesh like a body. I don't mind some mild stretching as a compromise.

Hello, try increasing the "Blend" factor in the image texture node. This should decrease the edge visibility

This results in an undesirable effect. For some I can blend, this one I cannot because it looks bad.

if you want only quads it's like solving a topolgy problem, maybe use an addon like Instant Remesh to make only quads from your mesh then find a way to bake the topology?

The mesh is mostly quads now,https://imgur.com/oA3Simf

in that case you can duplicate, subdivide, use a Wireframe modifier and bake the result?

Whats the process for that?

What I mean is how will baking the topology help? I am a bit new to blender.

I meant you can generate this kind of pattern using a Wireframe modifier on your mesh, then baking the result, I didn't mean you could use the pattern you're showing right now

Ah, I see. While true, what if I have a complex repeating texture? I'm not concerned about this specific texture so much as the way to make it wrap without issues.

For your textures, if the Image Texture Blend option doesn't fix the problem, I don't think there's any easy way to hide the visible seams. You could try to fix it in Texture Painting mode with the Stencil or the Clone brush, but it will really depend on the texture I guess.
So I probably misunderstood your question, but for the specific texture you're showing, a kind of grid, you could use your current topology:

Duplicate your object, hide the original. As suggested by Lemon, if you want a more dense and uniform net, use the Remesh tool/ Voxel option in the Properties panel > Object Data > Remesh:

If you want the topology to be rotated 45°, select all and CtrlE > Unsubdivide with an Iteration of 1 (Operator box), like that:

Go in Edit mode, switch to Face Select, select all, press i twice to inset the faces. Keep these faces selected, give them a material (here orange). Ctrli to invert the selection, give the strokes another material (here red):

Unhide the original torso, it must overlap its copy, go in Edit mode, select all, unwrap (Smart UV Project mode), in the UV Editor create a new image (size 2048 x 2048 for example), in the Shader Editor create an Image Texture node, don't plug it for the moment, load the image you've created. Make sure you're in Cycles, select the copy, shift select the original, go in the Properties panel > Render > Bake, choose Bake Type > Diffuse, disable Influence > Direct and Indirect, enable Selected to Active, give a bit of Extrusion value, click on Bake:

Once the map as been created, plug the Image Texture node into the Principled BSDF (or Diffuse), the map is now displayed on the surface of the original torso. If you use a Subdivision Surface modifier You may need to give some corrections in Texture Painting mode:

If want to follow the mesh geometry (but this is not exactly the question, though), use remesh.

could you please tell a bit more? Yes that was not the question but I thought using the topology was a way to answer, I don't see how to make a grid all over the body without any visible seam, using the topology seemed like a solution

few in fact... the question is about mapping not only a grid but any shape (and this is nearly a research project/algorithm)... but if you want to have (from your answer) a quad geometry which is regular, remesh will create quads with uniform size... so closer to the question. I've not tried it, though. Bon, je n'ai pour autant pas de vraie solution pour cette question, @moonboots.

oh yes I'm going to edit; merci  ;)

though, consider my comment was a general idea, not a poc... I don't want to lead things in a bad way...

okay I read again the comments and this grid was just an example, I still leave my comment

What I am hearing is that for 'complex' meshes, it has to be UV unwrapped to get a good result.

It really depends on the kind of texture you're talking about, if the texture has big visible patterns, it will be hard to make it work on complex objects like a costume for example, because we will probably see the seam, the trick for this kind of case is to put the seam where the camera won't see it, it may also be fixed with some painting correction


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What is the best way to make the B shape in this gif?
I am modelling a set of stairs:

and wish to turn them into a high polygon model to resemble this with clear spaces between the bricks and all bricks to be of the same size:

I saw the below gif from Rigid Body Dynamic Animation Problem but no way to reproduce the B it so that the model is made up of cubes with the edges of the model being smoothed or curved to fit the original mesh.

So far all I have is this built from arrays (I am aware I'll need many more) from this tutorial Destroying any object into cubes but my blender locks up for quite a long time and has yet to finish processing it:

Any suggestions?

Hello :). So are you asking how to do the stairs or how to do the letter B?

i think both :D

to make a b with cubes you could make a text "b", convert it to mesh, then remesh modifier and then instancing (vertices)

The B is simply the method I want to use, the stairs is how I want the shape to look. The remesh modifier doesn't keep the shape, it warps it with just about every way I fiddle with it.

I have created this [https://i.imgur.com/4MEh75N.png]   with that advice, but I don't think it's the correct method. It's not warping the shapes to fit, just adjusting their rotations.

In short, how do I do this? [https://i.imgur.com/lROdM24.png]

the remesh modifier does keep the shape. you just have to use it right. Tutorial:https://youtu.be/ILvt60KJsRM

I get a different, but similar and not quite correct result. Again, it doesn't warp, cut or edit the shapes only aligns them to the templated staircase. So the edges are jagged when they should be smooth.

In the end, I decided to use Destroying any object into cubes and breaking the model into a more simple geometry for my computer to handle.


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Boolean Modifier not working with Solidify Modifier
I am currently in the process of making a plane in blender. To cut out the windows I am using the Boolean modifier, and to add thickness to the windows I used the Solidify Modifier. I would first solidify the cylinder I am using as the body of the plane and then apply the Boolean. I ONLY apply the Boolean whilst my mesh is not shaded as smooth otherwise errors occur. When I have finished using the Boolean and shade the cylinder as smooth I get a problem where there are strange cut outs in the cylinder as shown in the picture. IF anybody could help it would be greatly appreciated.
Many thanks.

That is caused by bad normals splitting which is the consequence of the inproper topology - tiny long triangles or tiny long quads and / or Ngons composing that surface. The windows should be surrounded with one edge loop and avoid the kind of geometry with stretched faces.

Yeah, avoid booleans at all costs, they are a lazy way of modelling, and will only lead to problems down the road.

How would I go about adding edge loops around the windows?

This may help http://topologyguides.com

I would do two things to try and fix this. Firstly, you can try switching the order of which modifier is first.
Also, I'd try playing with the "offset" in the solidify modifier to see if that fixes it

Didnt seem to work just makes the same old shape and this time created a indent in the area around it.

This happened to me. It fixed its self up when I switched it from "Blender Internal Render" to "Cycles".
There was nothing wrong with the normals.

Switching Solidify Mode from Simple to Complex (with Thickness Mode: Fixed) did the trick to me.


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Same scene 1 GPU = OK, 2 GPUs = Out of memory?
Strange, strange problem this one.
Intro:
I had cycles with these 2 GPU + CPU working well for renders.
Then, after some time, I took the 750ti out and continued working with only the 1070ti + CPU until after some time,
I put the 750ti back in and this problem appears.

what I tried already:
-install new gpu drivers
-try with experimental versions (inclusing 2.8)
Important notes:
The scene you see (my startup file),
was rendering and previewing also before i took out the 750ti out the system

I don't think that is even possible as the two chipsets are different. but I checked anyway and there is no SLI enabling options in my nvidia control panel...

For SLI, you would disable it in the bios, it also has a connector you plug into the top of the cards to join them together. I think if it is active you will see SLI tuning options, not enable/disable but tuning options. So you had the 750 and added a 1070, took out the 750 and moved the 1070 to slot one, then put the 750 into slot two? They worked with the 750 in slot one but not with the 1070 in slot one?

checked and it is disabled in the bios and there is no tuning option in my nvidia control panel

I have the same problem with 2x K4000 cards in Blender 2.81 - we may have uncovered a bug! One K4000 with CPU works fine, adding a second one causes "out of memory" errors in an animation after a few frames. My cards are identical and work fine separately. I'll mention it to the Blender folks, if I find a solution I'll post it here.


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HOw to make sonic shader in cycles?

I am trying to make a shader like the blue shader below but can’t get it right. I have tried using a mix shader with two diffuse and a fresnel but it ends up way off from the what I’m trying to achieve.

What do you think of this picture?
I tryed to make it. just you need little more dark blue.

Thanks this is perfect but could you link me the image texture you used.

Here: http://prntscr.com/khz6zk


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How to make the background of rendered depth image black?
So I am trying to render color and depth image at the same time. The color image for the scene is:

As you can see, the background of this image is purely black. I want to have black background as well for the depth image. However, I could only get this:

My node editor looks like:

Is there a way to do so?
Any suggestions are appreciated!


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How to remove the edge of shadeless object?
I am trying to somewhat paint my object to a pure color. However, there is always a contour around it like
On the top, there is mug that I changed to pure yellow. However, I can always see the black edge around it after rendering. Is there any way to remove it?
Appreciated!

Try this - Select the mug, go to it's properties at right and open the "Display" tab. (it's down a fair way)  Either tick or untick it's "Transparency" box.

Thanks for the help. But no it does not remove the thing. I just want to paint the object to a color for labeling. Anyway to work around that?

If you're working in Blender's 3D window and wish to texture/label the mug, the 'shadeless' box is ticked as a rule.  Then you add a texture slot for the image.  I have no idea what method you are using.  Nodes and Cycles perhaps?

Great!  Can you tell us how you did it so we can learn?  Add it as an answer below.

Yes, you can check it below.

I found the solution which is quite simple.
Basically, when I change the color in Diffuse, I input the RGB in the range of 0 to 1 instead of 0 to 255. I guess Blender has some algorithm to handle it, which I am not quite sure.


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How to get camera matrix frame by frame in animation?
I am trying to create a 3D scene using blender. I have made a model and camera path using blender interface. However, I want camera matrix to be exported frame by frame as well.
I know using Python script interface might do the job. Thus, I am wondering if I can animate frame by frame and in processing each frame, I can output camera matrix as well.
I know bpy.ops.render.render(animation=True) can render all the frames at once. Is there a way that I can do frame-basis?
Any comments are appreciated.

import bpy
import os

scn = bpy.context.scene

for f in range(scn.frame_start, scn.frame_end + 1, scn.frame_step):

    # go to frame f
    scn.frame_set(f)

    # output the camera matrix on the current frame
    mat = scn.camera.matrix_world
    print(mat)

    # set the filepath
    scn.render.filepath = os.path.join("C:/my/path/to/file/basename", str(f).zfill(4)

    # render the current frame
    bpy.ops.render.render(write_still=True)


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Thickness to windows
I have been making a plane in blender for some time now and the one thing I cannot get around is adding thickness to windows on a plane. I have been making the plane using a cylinder and are NOT going to use sub surf to add a smoothing effect. Instead I am using the shade as smooth option. I am using the solidify modifier to add the thickness to the windows and then using boolean to cut out the shapes of the window. I have good sources that tell me it is possible to use boolean and still get good results. One the boolean as applied it completely messes up the surface of the cylinder. I have one refrence image as to what I would like the end result to be like.

Related question: https://blender.stackexchange.com/questions/81131/boolean-modifier-not-working-with-solidify-modifier?rq=1

The only way I've been able to do this without ugly streaks on the fuselage is to leave the geometry alone altogether and use 'inviso' masked windows instead.
Take a look at these two videos and judge for yourself if this is what you're after.   The results whilst suiting my own purposes, may not suit your own, particularly if for a 3D model that's to come under closer scrunity.  The links - https://www.dropbox.com/s/1lm9189tug5r08a/InvisoPortholes.mp4?dl=0   and the 2nd - https://www.dropbox.com/s/kd3p3ytrpl5lpz9/Rimmed.mp4?dl=0


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How to view image in solid mode in 2.8
Hello I have an image I am trying to use as a reference, but it only appears as a solid color in solid mode and only shows the actual image in render or lookdev. How do I make the image visible in solid mode where I do all of the modeling?
I already have it in front and have tried dragging the clip threshold up and down to no avail so I'm stuck.

I actually just figured it out. Go to the shading dropdown to the right of all the shaders then select texture as the color.

Good to know, I totally forgot about this feature :).

does this apply in wireframe as well


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How to rotate viewport?
I've tried changing the pivot port and everything like that and using the help page but I can't find a way to do what I'm trying to do. is there a way to rotate the entire viewport by a strict 90 degrees? I want to go from the left to the right.

Can you explain a little more about what you are asking? The question refers to rotating the viewport, but you mention moving the pivot point and the picture shows the hand model rotated ~90 degrees. If you want to rotate the hand, just hold down the ctrl key while rotating and it will snap to 5 degree increments. Alternatively, just select the hand in object mode, press N to bring up the side menu, and type 90 into whatever rotation axis you want.

Yeep. You are very right. Just had a mental malfunction. Thanks


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How to apply FK/IK for certain keyframes?
I'm animating a charracter and need him to switch between IK and FK controls for a certain action, but there's no way to set that afaik. If you set it at IK, the entire animation for that body part will play in IK. If you try to change it to FK, it sets the entire animation for that body part to FK.
How do I say, start in IK at frame 1, switch to FK at frame 20, and back to IK in frame 40 and so forth?

https://blender.stackexchange.com/questions/65290/how-can-i-seamlessly-switch-between-ik-fk

I saw that answer and it doesn't apply to my question. It didn't even answer that person question who asked it, who is asking the same thing as me.  He's telling you how to snap the IK controller to the FK position for a specific frame while still ultimately using IK controls, but what I want to do is have my mesh switch from following the IK controls to FK for any amount of frames. It wouldn't be very efficient to keep snapping the IK to FK position for like 30+ frames at a time.


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Cannot get clothing physics to work in animation
I have a character wearing a tunic with cloth physics applied. The upper part of the tunic is pinned so I can animate that manually, its only the bottom part with clothing physics applied so it can interact with my characters legs. Now I've rigged and am animating my character, and the bottom of the tunic is animating with cloth physics but it is not "moving with" the body that has a collider set on it. It just stays there in place while the rest of the rig clips through it.
Does anyone know why this is happening? Hopefully this makes sense or I can post pcs.

parent the cloth to the armature with automatic weights, also see this tutorial https://www.youtube.com/watch?v=AbyfuW5Aocg


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Why don't the fingers from the metarig rotate properly?
I searched for the answer but couldn't find it.
I added a metarig to the scene for my character. The complex one with a face and fingers. I've posed the rest of the skeleton in place, however the ringers are giving me grief, as in they will not rotate with the wrist/hand bone otherwise they break apart like so:

And I can't figure out how to resolve it. Does anyone have any ideas? Would adjusting my fingers in pose mode work? They rotate fine there, but I don't know if somehow doing it in pose mode will cause problems later on.

what do you mean when you say that they rotate well in Pose mode? Actually you are not supposed to animate in Edit mode but in Pose mode, but maybe share your file

When I say the fingers rotated well, I mean that when I selected the hand and fingers like in the above image, they rotated without breaking and disconnecting like you would expect. I wasn't animating at this point, I had only just added the metarig to the scene and was posing the skeleton to fit inside of my character so that it would apply auto-weights as correctly as possible. I was following a guide where the person was doing this in edit-mode so I presumed that was the "correct" mode to do so in. But I presume this can be done in pose mode as well? I can still share the file if needed.


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How can I initiate transform operations through python?
I'm trying to figure out how I can initiate transform operations like grab, scale and rotate. I don't want to execute the transform, just activate it so you can use your mouse and keyboard to perform the operation and accept.
Let me give you some context. I'm working on making a open hardware project to create a 3D mouse with arduino for blender. So far I am able to communicate between the board and blender by the use of python and a serial connection. I managed to find enough info to control the viewport with python so I can use a a joystick in conjunction with a rotary encoder to move around the modal. I would also love to add buttons that allows the user to customize its function to activate common tasks like scale, grab and zoom. Select all is an easy one but those 3 I'm having a hard time figuring out how to start the transform so the user can continue it. Even if I can't initiate the transform, is there a way I can fake a keyboard event though python in blender to make it think the user pressed G for grab?
Thanks, any help will be greatly appropriated.

you can simply call the appropriate operator like bpy.ops.transform.translate('INVOKE_DEFAULT') , faking keyboard events is more of python question see this


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Partialy applying multiresolution modifier
I have a very low poly mesh which has a multires modifier on it which has subdivisions set to 7. Is there a way i could apply a few subdivisions to the base mesh, but leave the multires modifier unapplied.This is dificult to explain so i will attempt to use images to help explain.
This is the base mesh:

This is the high res:

Now could i partly apply the modifier to the base mesh so it ends up lokking something like this:
But still keep the remaining subdivisions in the modifier so I can later apply them?

I don't think it's possible as of now (as I understand you're asking about something like Geometry > Delete Lower in ZBrush). The only thing you could make is to execute Apply Base to make actual geometry of the mesh (0 subd's) be in accordance with sculpting (rough one).

Old question but still I know at least a work around for this.
If e.g. you want to get rid of the levels 1 to 3 and keep only 4 to 7 you can do this:

Duplicate model
Go to level of detail you want as lowest (e.g. 4)
Apply Modifier
Add new modifier and subdivide till you have the same subdivision as the original one (in this case subdivide 3 times)
Add a Shrinkwrap modifier and set both Meshes to the highest level
Apply Shrinkwrap modifier

Done.


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Displacement map is completely white
I have baked a displacement map from a high poly sclupted mesh to a uv unwraped unsubdivided version of it, however the map is completely white and adds very little or even no detail to the mesh, even if I apply more subdivisions than the original mesh. I have tried placing the modifiers in different orders and that dosnt help.
here is the mesh with displacement modifier applied, the displacement map can be seen beside it:

And here is the high poly mesh the map was baked from:

Changing modifiers order won't give anything as you want Displacement to happen once there is enough geometry it to happen; and this will work only if Displacement is after Subsurf (if the latter needed). Although something strange's going on on your screenshots. The high-poly mesh has 4,5 mln. polys; the mesh with displacement (low-poly?) has 18 mln. So what is the purpose of the displacement then if amount of geometry is greater ?

I ramped the subdivisions up on the other mesh to see if that would help the displacement modifier, as you can see it didnt.

Remove the modifiers from your lo-poly model. You don't need them to bake a displacement map. Also remember, that displacement mapping does the rough details while normal maps then "produce" (fake) the fine details.


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How to sculpt folded skin
I'm trying to copy this model:
what tools should I use to create the wrinkles and growths on the neck? Is there a seed up the process or must it all be done by hand?

You can use the Texture panel in Sculpt Mode, as shown below:

This will apply a texture to your brush. If it doesn't look right, you can adjust the size of the texture under the "Size" portion of the panel. Additionally, you can use "Spacing" under the Stroke panel to adjust the sample rate(?) of the stroke.
Edit: Here is a video of the texture brush in action, at around 35 minutes in.

will the texture be able to create the larger growths on near the bottom of the neck and at the back?

For the back, I'm pretty sure he just used another texture. As for the bottom, I think you'd have to mess around with it a bit to get it right.


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How to create texture for sculpting from mesh
I've made this mesh that i want to use as a texture for sculpting, how should I do this?
would creating a normal map of it work?

You may render the AO of your sculpt and use it as an alpha texture for sculpting. Though I don't think it's a perfect method it gives a decent result.

I've quickly sculped some rocks to show you an example.

First remove all the lamps from your scene. Then add a material to your sculpt and set its specularity to 0.000

Select your camera and set its type to Ortographic. Set the Ortographic Scale to fit the sculpt borders as you want.

Go to World header, set the Horizon Color to black. Check the Ambient Occlusion checkbox (Add, Factor 1.000). In Gather panel choose the Raytrace and set the Samples to desired amount (the more samples, the more detailed alpha texture for sculpting'll be). Render, then save rendered image.

Now load your rendered image as an alpha texture in the Texture panel of the Sculpt Mode.

I used the Stencil mapping type with a harsh curve type to sculpt, but you may experiment with it.

NOTE: You may try to bake the AO (from the sculpt to a flat plane [selected to active]), save the result and then use it as the alpha mask for sculpting. I haven't tried this method though.

Thanks, this may be somewhat unrelated, but how did you make the high poly plane to sculpt on (subdividing a square turns it into a circle for me)?

I just subdivided the plane in Edit Mode many times to create a dense geometry and added a Subsurf Modifier with 3 subdivisions.


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Problem when reverse copying keyframe for walk cycle
Whenever I try to flip the first keyframe of my walk cycle it turns the pose into a wonky mess instead. I did some reading and figured that its something to do with bone axis alignment but i cant figure out how to fix it. Thank you in advane for the help.

Alignement is set by "Roll" property. You can access it in Edit Mode on your armature, on property panel N, for each bone.

You can also change roll on multiple bones, using Ctrl + N

In order to use correctly Mirror copying, if your Left bone has a X° roll, your right bone must have a -X° roll.


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How to bake displacement map to different object?
I have copied a high poly mesh, decimated it and uv unwrapped it. Can i now bake a displacement map from the high poly mesh onto the uv map of the low poly copy and apply it?

You have to have low an high poly mesh in the same position, enabled Selected to Active in Bake options and new image texture in each low poly mesh materials(if there is more then one) texture node. Then You select high poly mesh first and low poly second and hit Bake.If you would like to know more details, here is a good tutorial on this topic


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Inconsistent deformation with all vertices weighted to one bone. Certain vertices being affected differently
for some reason a few vertices don't deform correctly. The vertex value is at 1, I only have 1 vertex group for the mesh, there shouldn't be anything else affecting the vertices. normalizing weights doesn't help
the  issue also occurs when weights to multiple bones are applied to the vertices, i just tried applying a single weight for troubleshooting.

Got a file?  One explanation would be bendy bones.

Yeah, here it is. https://we.tl/t-iOmvcrHnxP Im not sure if there are bendy bones, but if there are id like to disable them if possible since i don't need them. I'm using rigify

Yup, bendy bones.
We can see what bones have bendy bones by changing the display to Bendy Bone, and disabling shapes.  (Man, I hate shapes, extra work just to give the animator less information.)  When we do, we see that the bone to which your chest/vest is weighted is controlled by bendy bones:

So are quite a few other bendy bones.  Which you'll want to be aware of for further work.
To change a bone to stop being bendy, you just have to change the segment count to 1, in properties/bone/bendy bones/segments.
I'm not into Rigify, but I've seen a lot of problems from Rigify users related to bendy bones.  It appears that there was a recent change that made almost everything bendy, and that it's causing a lot of users problems.  There should be some way to prevent this from happening if you do some searching on Rigify documentation (bendy bones are not an unalloyed good, as demonstrated here.)

I've got segments set to 1 in the metarig so I assumed it would generate without bendy bones. Is there a way to stop rigify from generating bendy bones or disable them across an entire armature?

Not a rigify user, I couldn't tell you.  Search for documentation.

Thanks for the help. The issues fixed, ill check the documentation.


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Legs twisting in rig
The legs on the mesh I'm trying to animate are twisted, no matter what pole angle I select.Here is the file : http://www.filedropper.com/potato

The rest position of the knees have a slight backwards bend to them, but they should instead have a forward bend.  Once the bend was added, zero-out the rolls on each bone to 0 degrees, and in the IK constraint settings, change the Pole Target angle on leg bottom.R to 0 degrees, and the leg bottom.L to 90 degrees.


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Specific vertices shoot off in random directions when bevelling
I am currently trying to create a basic wheel-like shape to test out blender and work out some of the key shortcuts on Mac.
I am encountering an issue when I try to bevel specific edge loops, please see the pictures:

I fully anticipate that I have some sort of geometrical inconsistency - I have tried some options from mesh>cleanup on the whole mesh object as detailed in this answer like 'merge by distance' or 'split non-planar faces' (I don't really actually know what that does but I hoped it might make any doubles more obvious).
The issues pictured only occur on these edges, others around it are fine

This turned out to be an easy fix, somewhere along this line my 'surface normals' got all messed up, and Blender's vertices follow their respective surface normals when transforming like in the bevel tool.
To resolve this problem (unless you have custom surface normals and resetting isn't an option) is to simply select the area which is not behaving as expected (in this case the edge loops and recalculate normals. For Mac the shortcut for this is shift + N.
See more about it here


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Set Array modifier to duplicate the object in both directions
I modeled an object and want to have it 5 times in a row. I am using the arraymodifier, set the offset in my desired achsis to 1,1 (for a small gap) and the count to 5. My problem is now, that this extends the object to one direction only. I want my modeled object to stay in the center, 2 copies left, 2 right. I tried adding another array modifier with the negated offset, but that modifies the output result of the first one, obviously.
Is there a way for doing this? I could of cause apply my modifier and move the object back to where it belongs, but i dont want to apply yet and also i'm curious now if there is a solution for this.

Been there too, but I don't think this is possible using the normal array modifier.

You sure know how to ask the popular question!  Perhaps you can ask questions for me.

Works with three Modifiers for a x-Axis symmetrical centered model from Front view:

Just add your Array Modifier to your object for the right two duplicates.

Then Add a Cube, translate it 1 BU to the left (minus x-Axis) in Edit Mode (thus keeping its Origin) and scale it up if necessary to encase the complete left half of your Mesh.

Now add a Boolean Modifier behind your Array Modifier selecting this Cube as Object in Difference Mode splitting your center Object in half, optionally hide the cube (H) and afterwards

Add a Mirror Modifier to replicate the right half to the left side...

Wow, that actually is a nice way i haven't thought of, but it has one problem: It only works with symmetrical objects. When using this method and trying to edit the shape in an un-symmetrical way you dont get the desired result

@ErikBrendel: As mentioned ;-)
feel free to Upvote if you like it... I'm thinking about a different solution for asymmetrical models... Try using symmetrical ones for now.

Oh i didn't realize the first line :)

@ErikBrendel: Added another answer for asymmetrical models... give it a try and some feedback - the workflow is pretty similar.

looks a bit like overkill but might come in handy someday. thanks for sharing.

For asymmetrical Models it's a bit more complicated and they should be non-manifold (e.g. Suzanne might get her eye lost) but the principle is like in my other answer.

Just make a linked Duplicate (AltD) and leave it at it's position, you might Parent it to the original mesh. As it shares the Datablock all further edits will be applied as well. I use a two colored one-sided-deformed Suzanne here for demonstration purposes.
Then add a 3-count Array Modifier to your original Object with your 1.1 Offset and
add the Cube translated -1x in Edit Mode and hide it.
Add a second Cube, translated 1x in Edit Mode and hide it.
Add your Boolean Modifier with the first left-translated Cube to your original Object in Difference mode.
Add the same Array and Boolean Modifiers but with a negative Offset to your linked-duplicated Object and the second right-translated Cube splitting your Object in half.

In the above image the yellow center object has no array modifier.  The two flanking object meshes have array modifiers and are cyan in color.  We assume you have a desire to change the number of copies of the mesh.  There is no symmetry requirement.  The two different colors are for explanation purposes only.  Change the number copies in both array modifiers as suits you.

Use 3 object meshes, right side, middle, left side. They share the same mesh datablock, and appear identical.  Both cyan flanking meshes have array modifier in the different directions.  Relative offset 1 and -1 for example.
You can animate the visibility of the cyan flanking meshes to appear later than the center.  The camera icon in the outliner allows you to do this.  Insert a keyframe as indicated.

Please be more artistic and excruciatingly exact then the example above.
If your scene were more complex a simple driver may help to keep the [count] value the same across the two array modifiers.
Mirror Modifier may come into play.
An empty with a negative axis scale may come into play

I think it would be useful to expand on some of these bullet points to explain how to do them.

Okay, based on the answer of @atomicbezierslinger (wich gave me the idea) i did it now as following:

In object mode i created a Linked copy of my object (with Alt-D) and left it at the same position (RMB)
I added a modifier to each object, one time with an offset of +1,1, on the other object with -1,1
The count of each modifier was at 3, to get 5 resulting objects (in reality there are of course 6, but two are directly overlapping... When applying the modifier one may need to remove one of the overlapping instances)
There we go. When editing one objects vertices in edit mode now, through the linked copy and not-yet-applied modifiers, all copys are modified (even though you see the change not instantly on the linked copy)

Important annotation: Hitting Apply Rot+Scale on the object before doing these steps can prevent from weird errors


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Compare 2 images directly
I would like to compare 2 images with little color changes to another. (To be specific, the raw render result and the output of my compositing viewer-node).
For now, i use two UV/Image Editor windows, displaying my two images. The problem now is that i need to resize/move both images so that the edge is fitting correctly (wich is unpleasent work). Also, when moving the border around, both images also move a bit...

Is there a better method to display two images on top of each other with a movable border between them?

The Render Result of the UV/Image Editor has 8 slots for render output. I VERY often used this to compare changes between different renders.
To use different slots, open the Render Result F11 and press the number of the slot you want (1 thru 8). Then render. The result will show up in that slot. Now, press the number of another slot (1 thru 8) and render again. Now, you can swap very quickly between the two (or more) results without having to re-render. You won't have a movable border, but you will be able to compare your renders to each other.


text:
Is there a way to scale uv pupils?
Let’s say I have a cartoon character with flat and oddly shaped eyes. In this case I’m using a material with an image texture. I tried animating the pupil by having two images, one with a bigger pupil and one with a smaller pupil, and then switching between the two using a mix shader node. But when I tried animating this, as I figured, the pupil has an effect of fading into the next image, rather than shrinking. How should I fix this?

Does it need to be a shader? Why don't you use a shape key?

if at frame 1 the Factor of your Mix shader is at 0 and at frame 2 it is at 1, there should not be any fading

Well, It's a little tricky because my animation has a pupil that slowly dilates. I can't use a shape key because it's an image texture.


text:
How to find out in which View_3D window/screen the Add-on button was pressed?
I have an Add-On which resides in the N-Panel of the View_3D window.
From this Add-on, I would like to manipulate the current view with buttons.
As there are many View_3D view ports in Blender and all of them has my Add-on in their respective N-Panel, I need to find out in which of those View_3D windows was the button pressed so I can manipulate the view matrix of that view port.
Is there a simple way to get that screen without fiddling with the location of the mouse pointer?

Three ways to get the active SpaceView3D link
context.space_data
context.area.spaces.active
context.area.spaces[0]

This works because all sidebars are part of an area View3D. No need to override the context here. For matrix you need datas from View3D.region_3d [RegionView3D] link
import bpy

### UI
class TEST_PT_Panel(bpy.types.Panel):
    bl_idname = 'TEST_PT_Panel'
    bl_label = "Test Panel"
    bl_space_type = 'VIEW_3D'
    bl_region_type = 'UI'
    bl_category = "TEST"
    def draw(self, context):
        tool = context.scene.tool
        layout = self.layout
        layout.prop(tool, 'bool')
        layout.operator('test.operator', text="Test Operator")

### OPERATOR
class TEST_OT_Operator(bpy.types.Operator):
    bl_idname = 'test.operator'
    bl_label = "Test Operator"
    bl_description = "...testing"
    def execute(self, context):

      # get active space:

        activeA = context.space_data
        activeA.overlay.show_overlays = not activeA.overlay.show_overlays

        activeB = context.area.spaces.active
        activeB.show_gizmo = not activeB.show_gizmo

        activeC = context.area.spaces[0]
        activeC.show_region_toolbar = not activeC.show_region_toolbar

      # get matrix example

        r3d = activeA.region_3d
        view_mat = r3d.view_matrix
        print("view matrix: ", view_mat)

        return {'FINISHED'}

### PROPERTIES
class Test_Properties(bpy.types.PropertyGroup):
    bool : bpy.props.BoolProperty(default=False)

### REGISTRY
classes = (
    TEST_PT_Panel,
    TEST_OT_Operator,
    Test_Properties,
    )

def register():
    from bpy.utils import register_class
    for cls in classes:
        register_class(cls)
    bpy.types.Scene.tool = bpy.props.PointerProperty(type=Test_Properties)

def unregister():
    from bpy.utils import unregister_class
    for cls in reversed(classes):
        unregister_class(cls)
    bpy.types.Scene.tool

if __name__ == "__main__":
    register()

Thank you. Now I stumbled on to the next problem. I wanted to apply the matrix from a camera to the view_matrix but obviously they are not "interchangeable" as the view is 90° turned (X axis) and mirrored on the Y axis. How do the Matrix of a camera relate to the region_3d.view_matrix?

I figured it out. The camera matrix needs to be inverted. (  view_matrix.inverted()  )


text:
How to Save Sverchok nodes
I'm new to Sverchok and I don't quite understand how to work with it.
I watched lot's of videos but none of them showed how to include Sverchok in the Blender workflow.
I created some nodes and successfully generated objects with it.
I saved my Blender file and quit. The next time I opened the file, the generated objects were there but I can't find the Sverchok node structure anymore and so I'm not able to further tweak the generated objects.
(1) How do I save a Sverchok Node Structure?
(2) Is it not saved inside the Blender File?
(3) Does it stays connected to the generated objects after reopening the file?
Sorry for the newbie questions and thanks for any suggestion.
BR Steve

In the middle of the top bar of the sverchok node creation area, you need topick the right node graph from the drop down list, just as in the material editor.
It is saved in the Blender file and should work after reopening your scene, however updating to a new sverchok version can break stuff.

Something similar happens with Materials/node trees that are not used by any objects (ie - don't have "users". Objects produced by Sverchok don't automatically make those objects a user of a Sverchok node tree. You might need to press the "F" icon in the nodetree header toolbar (or Shield icon in 2.8+), to add a fake user to the node tree, then save.
The issue is Old. We discuss this on the Sverchok issue tracker back in 2014 - https://github.com/nortikin/sverchok/issues/356 )


text:
How to use an internal text file in an Add-on
Can someone show me an example how I can read the content of an internal text file?
Let's say I append a text file from another Blend file with a known internal name ("Environment") and some text data in it. I would like to read an process the content from within an Add-on. I know how to read an external file but I would like to keep this text file internal (after the append) so that it gets saved with the blender file.
I can access the internal file with: bpy.data.texts['Environment'].
I tried autocomplete after this and there are lot's of possibilities but I can't figure out how to simply read or write the content of this data block. What is the "best practice" to do this? Thanks for any suggestion.

This might help you, here's a link to the relevant docs. https://docs.blender.org/api/current/bpy.types.Text.html I think you want for line in text.lines: print(line.body) or text.as_string()

A couple old links you may find useful for the basic access to text data block contents. https://blender.stackexchange.com/questions/181187/read-the-contents-of-a-text-datablock?rq=1 https://blender.stackexchange.com/questions/178120/how-to-append-text-to-the-end-of-a-text-datablock-with-python?rq=1

Below are a few funtions I had setup in an old script that can provide some insight to reading, writing and working with data from a text datablock.
Sample writing to a data block:
Pass a mesh object to the function to create a new (or overwrite an existing) text datablock in the current blender session based on the name of the object.
def mesh_to_txt(obj):
    txtname = obj.name
    verts = [v.co for v in obj.data.vertices]
    edges = [e for e in obj.data.edges]
    faces = [f for f in obj.data.polygons]
    if txtname not in bpy.data.texts:
        ntxt = bpy.data.texts.new(txtname)
    else:
        ntxt = bpy.data.texts[txtname]
        ntxt.clear()
    # verts
    ntxt.write(f"verts = [\n")
    for v in verts:
        ntxt.write(f"\t{v.to_tuple()},\n")
    ntxt.write(f"\t]\n")
    # edges
    ntxt.write(f"edges = [\n")
    for e in edges:
        ntxt.write(f"\t[")
        for v in e.vertices:
            ntxt.write(f"{v},")
        ntxt.write(f"],\n")
    ntxt.write(f"\t]\n")
    # faces
    ntxt.write(f"faces = [\n")
    for f in faces:
        ntxt.write(f"\t[")
        for v in f.vertices:
            ntxt.write(f"{v},")
        ntxt.write(f"],\n")
    ntxt.write(f"\t]\n")

A new text block will be created based on the name of the selected object and data formated like so:
verts = [
    (1.0, 1.0, 1.0),
    (1.0, 1.0, -1.0),
    (1.0, -1.0, 1.0),
    (1.0, -1.0, -1.0),
    (-1.0, 1.0, 1.0),
    (-1.0, 1.0, -1.0),
    (-1.0, -1.0, 1.0),
    (-1.0, -1.0, -1.0),
    ]
edges = [
    [5,7,],
    [1,5,],
    [0,1,],
    [7,6,],
    [2,3,],
    [4,5,],
    [2,6,],
    [0,2,],
    [7,3,],
    [6,4,],
    [4,0,],
    [3,1,],
    ]
faces = [
    [0,4,6,2,],
    [3,2,6,7,],
    [7,6,4,5,],
    [5,1,3,7,],
    [1,0,2,3,],
    [5,4,0,1,],
    ]

Reading data from a text datablock
Function that when given a string name corresponding to a text datablock reads the above format creating lists to use elsewhere. If the name provided txtname is not found in the currect blend session the return values are empty lists.
def txt_to_mesh(txtname):
    verts = []
    edges = []
    faces = []
    line = 0
    if txtname in bpy.data.texts:
        ntxt = bpy.data.texts[txtname]
    else:
        return verts, edges, faces
    ntxt.cursor_set(line, character=0, select=False)
    rd_line = ntxt.current_line.body

    if rd_line.startswith('verts'):
        line += 1
        ntxt.cursor_set(line, character=0, select=False)
        rd_line = ntxt.current_line.body
        while rd_line.startswith('\t('):
            verts.append(mathutils.Vector(eval(rd_line[1:-1])))
            line += 1
            ntxt.cursor_set(line, character=0, select=False)
            rd_line = ntxt.current_line.body
        # skip to edges or faces
        while rd_line.startswith('\t'):
            line += 1
            ntxt.cursor_set(line, character=0, select=False)
            rd_line = ntxt.current_line.body

    if rd_line.startswith('edges'):
        line += 1
        ntxt.cursor_set(line, character=0, select=False)
        rd_line = ntxt.current_line.body
        while rd_line.startswith('\t['):
            edges.append(eval(rd_line[1:-1]))
            line += 1
            ntxt.cursor_set(line, character=0, select=False)
            rd_line = ntxt.current_line.body
        # skip to edges or faces
        while rd_line.startswith('\t'):
            line += 1
            ntxt.cursor_set(line, character=0, select=False)
            rd_line = ntxt.current_line.body

    if rd_line.startswith('faces'):
        line += 1
        ntxt.cursor_set(line, character=0, select=False)
        rd_line = ntxt.current_line.body
        while rd_line.startswith('\t['):
            faces.append(eval(rd_line[1:-1]))
            line += 1
            ntxt.cursor_set(line, character=0, select=False)
            rd_line = ntxt.current_line.body
        # skip to edges or faces
        while rd_line.startswith('\t'):
            line += 1
            ntxt.cursor_set(line, character=0, select=False)
            rd_line = ntxt.current_line.body
    return verts, edges, faces

Using information read from datablock:
Function to create a mesh object from verts, edges, faces.
def add_mesh(name, verts, faces, edges=None, col_name=""):
    if edges is None:
        edges = []
    mesh = bpy.data.meshes.new(name)
    obj = bpy.data.objects.new(mesh.name, mesh)
    if bpy.data.collections.get(col_name):
        col = bpy.data.collections.get(col_name)
    else:
        col = bpy.context.scene.collection
    col.objects.link(obj)
    bpy.context.view_layer.objects.active = obj
    mesh.from_pydata(verts, edges, faces)


text:
Control (move) vertices in a vertex group by a control mechanism with Geometry Nodes
I would like to create a general control mechanism for a vertex group.

As the image shows, I would like to be able to move vertices (they belong to a vertex group) with some control mechanism (a ColorRamp or another Mesh Line) and blend the movement between the control instances. Preferably the movement should be based on the normal of the corresponding front face or if that is too complicated than at least in separate X and Y directions. First I thought of a ColorRamp as the control instance (with external min/max values to limit the amount of movement) and somehow drive with that the position of the vertices with smooth blending for the in between vertices. I guess this is very complicated so for a start a simple line mesh with a couple of vertices as control points would also do the job.
I find GN very complicated and have actually more and more problems to grasp it from Blender release to release. (Especially if the task is more than just simple scattering).
I'm using Blender 3.2.
If someone has the time, could you give me small examples for:

how do I reference Vertex Groups?
how can I distribute the movement of lets say 4 control points of the mesh line to lets say 100 vertices of the group and blend in between them smoothly? (A ColorRamp would give the option for different blending methods.)
how (and if) can I move the vertex in the direction the corresponding front surface is pointing? (The front surfaces can also be in a separate vertex group. They would have the same # as the "spikes)

Is this at all doable with geometry nodes?
Thanks for any suggestions.

You may do something like this:

how do I reference Vertex Groups?

Use Named attribute node.

how (and if) can I move the vertex in the direction the corresponding front surface is pointing? (The front surfaces can also be in a separate vertex group. They would have the same # as the "spikes)

You can use Normal input node.

how can I distribute the movement of lets say 4 control points of the mesh line to lets say 100 vertices of the group and blend in between them smoothly? (A ColorRamp would give the option for different blending methods.)

In my example, I've got the polar coordinate using arctan2 (math node). These returns coordinate from -pi to pi (-180 to 180 deg) so I've mapped them to 0-1 interval before curves.

Fantastic, thank you! It is much simpler as I thought. I tested it and it works but I still don't understand the "normal" part. How can I restrict the movement of the vertex to the normal direction of the corresponding front faces? The Normal Input takes the normal of the actual vertex (which I move) or am I wrong? In my example the setup works as the normal of the vertex is the same as the normal of the front face. My actual object is more complex so the normal is different than the front face. Can I somehow reference the normal of a second Named Attribute (with the front faces Vertex Group)?

Vertex group are "vertex", not "faces" group :-) how it supposed to detect face that's corresponded to vertex?

How true... silly me. =))


text:
How to scale by increment?
I have snap turned on and it works just fine when I'm moving an object. But is there a way to have my object snap to grid increments when I am scaling?

Just turn on "Affect Scale" in the snapping settings.

Now just hold left Ctrl and your scale should snap.


text:
Reset camera orientation?
Hi so I shrunk my mesh down a great deal from 20 meters in height to about 2 and now the camera orientation is really weird. How do I reset it to move around my shrunk mesh instead of still behaving like it is moving around the larger one?

Select the mesh and press the period key on the Numpad.


text:
How to hide toolbar on right side?

Hi, how do I hide the highlighted tollbars without hiding the ones at the bottom? I tried space+shift but it hides both of them.

You can click and drag the small triangle in the corner of the windows (toolbars) to collapse them. https://docs.blender.org/manual/en/dev/interface/window_system/tabs_panels.html https://youtu.be/4q6mLdO1E4Q

That doesn't work. It just makes duplicate toolbars within the area. And the video doesn't hide the toolbars I highlighted in red.

Keep the courser in 3D window and press ctrl+spacebar it will hide all the windows. Its toggle key

Click and drag the corner triangles in the direction you want them to collapse.
This might help.

this SHOULD work.. I can slide the panel down, but can't slide my 3D view to the right. I would record my screen but I don't have the software/equipment.

Try collapsing the Dope sheet and timeline first, and then perform the steps mentioned in my answer. Blender's youtube channel has some good beginner videos regarding this like this one https://youtu.be/Yb00Tuv0Rhw?t=397

I think I did that somehow by mistake and it suddenly worked. Tried YT but didn't see one that specifically mentioned my problem. Thanks anyway.

Actually, it is not you fault since many beginners suffer with the same problem like yours because blender's interface is not that intuitive in this regard. I would suggest you to spend some time practising collapsing/expanding windows.

There is another way. You can also do this:

This is the point. You can't drag a panel over a junction between two other panels.


text:
Use shrinkwrap on certain vertices?
By default when you use shrinkwrap, it takes the whole mesh of the selected object and wraps it to the target object. What I want to know is if I can get this result using certain vertices, so that they can wrap closer to his wrists, ankles and waist like cuffs on clothing, without making the entire mesh look skintight.

In your object, in Edit or in Weight Paint mode, you just have to create the vertex group that is supposed to stick to the Target object, then add your Shrinkwrap modifier and choose this group in Vertex Group.

Also note that the more your vertice will be part of the group (i.e. from 0 to 100% weight), the more it will stick to its Target object


text:
Mesh is really weird importing to 2.8
It seems like moving my mesh to 2.8 is making it do some really bizarre stuff. For example, I had a mirror modifier that worked exactly as intended in 2.79 but now when I go into edit mode, modifier still on mind you, I can freely select all vertices on both sides of the mesh. When I delete some vertices thinking that it somehow duplicated the mesh I just see another mesh beneath it in object mode. but when I go back into object mode and move my mirrored mesh to see if there is another one under it, there isn't, and I'm just stumped at whats going on.
Can anyone help?
https://drive.google.com/file/d/1neePPk9PlKjhpp8AIbUOF94m1KHws7hX/view?usp=sharing

It looks like the mesh in the .blend file is already mostly symmetrical, so it shouldn't need a mirror modifier.
Anyways, if you want to fix this, simply select all of the vertices left of the center (facing the mesh, it's the character's right) and delete faces (x > f). Then you'll have what you want.


text:
How to change the arc of vertices?
You can see how the vertices are right now, but the red line is what I am trying to achieve. How do do I do this?

Scale the vertices by -1.0 on, in this case, the Z axis. This should flip them as you wish.


text:
How do I straighten out my loop cuts?
In the image below all of my loop cut vertices are off track from each other. From a front ortho view they are placed very messy on the faces and are out of line with each other. How do I make them more in line with each other like the above loop cuts?

What I'm understanding is that you'd like to bring the vertices of the back face of your object to be directly behind the corresponding vertices of the front face, down global Y (since you are in Front view)
If the back faces are the same shape as your front faces, and shifted, (not rotated) with respect to the front faces, you can set your snap to Active and Vertex, select all the vertices you want to move, making a convenient vertex the last selected (and therefore active) and GShift
Y the vertices, snapping the active vertex to its counterpart in XZ.
If not, another possible move -

Select the back vertices, and (without Automatic Merge switched on)   G G slide them down their edges until they meet their front partners. (You may have to do this in more than one bite). Then  GY them to your required depth.
Or.. it may be more economical to delete the back faces, and make a brand new  extrusion in Y (EY).
It's possible that the result is not the one you're looking for..

Last solution was perfect. I deleted all the vertices behind the front facing ones and extruded them back on the Y axis. But they looked funky and uneven so I just went to specials>looptools>flatten and locked the XY axes to get the conformity I was looking for. Preciate it.


text:
Importing to UE4 without smoothing?
I have a model I'd like to export to UE4 but I'm going for a low poly "look" and want to keep the jagged and blocky look it has. Is there a way for me to export it into UE4 without the smoothing effects?

The approach may depend on the format you're using for the export. Have you tried marking all edges as sharp in edit mode (CTRL + E > Mark Sharp)? If that doesn't work the edge split modifier will likely work.

Firstly, you can follow LuckyCOINNNN's insttuction or go to the data tab of the object and enable auto smooth and set to 0.

Figured it out. I just needed to change the import setting on normals to import Tangent and Normals.

Ahhh... that'll do it... wierd though as the importer usually defaults to that.

Firstly, follow LuckyCOINNNN's suggestion (although I wouldn't recommend using the split edge modifier, as it will separate all your edge verts), or go to the data tab of the object and enable Auto Smooth with a value of 0 (if you are doing this method you must select all faces and set to shade smooth first), or you can select all faces/verts/edges and set to Shade Flat.
Secondly if you're using FBX to export to UE4, in the Geometry section of the exporter set Smooth to Edge (I think Face also works).

Thanks for the response, but I can't seem to find the Auto Smooth option in the data tab.

I modified my answer with a pic for ya :-D

Thank you. As it turns out, that option isn't selected. Strangely enough on a recent model I just made, importing THAT one to UE4 doesn't auto-smooth it, but the original one still does. I must have ticked some box somewhere that made it do this. But the only difference that comes to mind now is that the model that is auto-smoothing has a full armature with rig and animations, but I don't believe that would make it smooth.

It won't apply the auto smooth if you don't  set all the models poly's to Shade Smooth (Edit mode/ select all/ ctrl-f/ select Shade Smooth about 2/3rds the way down)... It sounds to me like that step may have been missing on the model that wouldn't work.

Yeah, it still imports smoothly whether the shade is set to flat or smooth.

Because you have to set the fbx export, under the Geometry section, you have to set Smooth to Edge (I THINK face works as well)


text:
add clothing physics to a PART of mesh?
I'm trying to figure out how to add clothing physics to a portion of the mesh and keep it attached to the object. In the picture, I want to add physics to the highlighted faces and leave the rest of the box solid. How do?

You have to create a vertex group.
There is a video tutorial on making a flag by BornCG ( https://www.youtube.com/watch?v=sOtRsHYCzEE&list=PL006307E237BB7FF6&index=21 ) that shows you pretty well how to do this.
Essentially, you add the physics to the entire mesh, then select a vertex group to ignore the physics and remain stationary.
My knowledge in blender is only a few months old so please excuse if this does not solve your problem.


text:
Is there a way to delete a Material by name from a Python script?
I have a script in which I read an FBX File in and replace the input material with a Blender material. The old FBX material remains in the scene tough until the file is closed.
I have the name of the old material but I can't find a way to remove it from the file right after the conversion.
In the Blender UI, in the Object Lister -> Blender File section I can delete any material immediately out of the file. (Unfortunately the Information Window doesn't show any meaningful code to this operation.)
Is there a way to do the same from within Python?

Just get your material, for instance
 m = bpy.data.materials['Material.001']

Then remove it
 bpy.data.materials.remove(m)

You can also check if m.users is 0 to be sure the material is not in use somewhere.

Oh, that was simple. Thanks!


text:
How do I select the top "Scene Collection" from python?
I would like to select the top Collection (called "Scene Collection") from my script.
If I test any other collection in the scene in the console with:
bpy.context.view_layer.active_layer_collection.collection
I get something like: bpy.data.collections['Collection']
But if the top "Scene Collection" is active, I get: bpy.data.scenes['Scene'].collection
Therefore a code like this:
collections = bpy.context.view_layer.layer_collection.children
for collection in collections:
    if collection.name == "Scene":
        bpy.context.view_layer.active_layer_collection = collection

don't work as this top collection is not among the "normal" collections.
Is there a way to select it out of a script?
(To make sure that anything new created out of the script will originate under this top collection and not inside some other collection which were created previously from the script.)

It seems you answered yourself. To get the Scene collection, use bpy.data.scenes[...].collection or bpy.context.view_layer.layer_collection if you're after the current main collection. You already do this in your code. You're not going to have the main collection within the children of the main collection, therefore the check you want to perform will always yield False.
If you have a list of collections obtained in another way, consider comparing a collection with the main collection like so:
if some_collection == bpy.context.view_layer.layer_collection:
    # ...

Thanks! Not seeing the forest from a tree. =)


text:
Changing Panel UI content based on user input
Is it possible to change the content of a custom panel based on user input?
Let's say I have a panel with an explanation text (Label) and a button which starts the function. As soon as the user pressed the button, I would like to change the text and replace the button with another one which executes some code. When this new button is pressed and the function "behind" is finished, I would like to switch back to the initial text and button.
Is this possible?
import bpy

class ButonOperator(bpy.types.Operator):
    bl_idname = "scene.button_operator"
    bl_label = "Add-On Function"

    def execute(self, context):
        # Start the Add-on. Here I would like to swith the content of the label below
        # ("Sample text") and replace the "Add-On Function" button with a "START" button.
        # This should invoke another operator and when that is finished I would like
        # to restore the initial state.
        pass
        return {'FINISHED'}

class TestPanel(bpy.types.Panel):
    bl_label = "Test Panel"
    bl_space_type = 'VIEW_3D'
    bl_region_type = 'UI'

    def draw(self, context):
        self.layout.label(text="Sample Text")
        self.layout.separator_spacer
        self.layout.operator("scene.button_operator")

def register():
    bpy.utils.register_class(ButonOperator)
    bpy.utils.register_class(TestPanel)

def unregister():
    bpy.utils.register_class(ButonOperator)
    bpy.utils.register_class(TestPanel)

if __name__ == "__main__":
    register()

Short answer yes it is possible. eg self.layout.label(text=some_object.some_property_i_set_with_operator)

Here is a variation of your script that does the simple two state version of what you describe.  An explanation follows.
import bpy
from bpy.types import Operator, Panel
from enum import Enum

class Choice(Enum):
    Uninitialized = -1
    One = 1
    Two = 2

class ButtonMachine:
    def __init__(self, initialState = Choice.Uninitialized):
        self.state = initialState

machine = ButtonMachine(Choice.One)

class MISC_OT_ButonOneOperator(Operator):
    bl_idname = "scene.buttonone_operator"
    bl_label = "Add-On Function 1"

    def execute(self, context):
        machine.state = Choice.Two
        self.report({'INFO'}, "one")
        return {'FINISHED'}

class MISC_OT_ButonTwoOperator(Operator):
    bl_idname = "scene.buttontwo_operator"
    bl_label = "Add-On Function 2"

    def execute(self, context):
        machine.state = Choice.One
        self.report({'INFO'}, "two")
        return {'FINISHED'}

class MISC_PT_TestPanel(Panel):
    bl_label = "Test Panel"
    bl_space_type = 'VIEW_3D'
    bl_region_type = 'UI'

    def draw(self, context):
        if machine.state == Choice.One:
            self.layout.label(text="- 1 -")
            self.layout.separator_spacer
            self.layout.operator("scene.buttonone_operator")
        elif machine.state == Choice.Two:
            self.layout.label(text="- 2 -")
            self.layout.separator_spacer
            self.layout.operator("scene.buttontwo_operator")
        else:
            self.layout.label(text="lost")

def register():
    bpy.utils.register_class(MISC_OT_ButonOneOperator)
    bpy.utils.register_class(MISC_OT_ButonTwoOperator)
    bpy.utils.register_class(MISC_PT_TestPanel)

def unregister():
    bpy.utils.unregister_class(MISC_OT_ButonOneOperator)
    bpy.utils.unregister_class(MISC_OT_ButonTwoOperator)
    bpy.utils.unregister_class(MISC_PT_TestPanel)

if __name__ == "__main__":
    register()

Explanation
What you are asking about is often implemented using a state machine pattern.  When the system is in a given state, then an action can transition it to another state.  A global variable is used to keep track of the state the system is in.  When actions are performed that change the state of the machine, this fact is recorded in the global variable.
Since the system can only be in a finite number of states, an Enum is often used to record the state and the state machine is implemented as an if statement with a number of branches, one for each state, and a final branch in case there is an error.
I've implemented a two-state machine. ButtonOne is the state where the first button should be available and ButtonTwo is for the second.  Each button changes the state when they're pressed.
The actual state machine is the if statement in the Panel draw function.
There are more sophisticated ways to implement this, but this version shows how the system works very clearly.  If I had a lot of states, I would use a dictionary with one entry for each state containing a tuple.  In the example, the tuple would contain the text string for the label, the function that goes with the state, and the value of the Enum for the next state.
Alternate Implementation
Here's a version using a dictionary and a transition class.
import bpy
from bpy.types import Operator, Panel
from enum import Enum

class Choice(Enum):
    Uninitialized = -1
    One = 0
    Two = 1
    Three = 3

class ButtonMachine:
    def __init__(self, initialState = Choice.Uninitialized):
        self.state = initialState

def nextState(state):
    currentState = states.get(state)
    if currentState:
        return currentState.nextState
    else:
        return None

class Transition:
    def __init__(self, newText = "None", newOperator = "None", newState = Choice.Uninitialized):
        self.displayText = newText
        self.stateOperator = newOperator
        self.nextState = newState

class MISC_OT_ButonOneOperator(Operator):
    bl_idname = "scene.buttonone_operator"
    bl_label = "Add-On Function 1"

    def execute(self, context):
        machine.state = nextState(machine.state)
        return {'FINISHED'}

class MISC_OT_ButonTwoOperator(Operator):
    bl_idname = "scene.buttontwo_operator"
    bl_label = "Add-On Function 2"

    def execute(self, context):
        machine.state = nextState(machine.state)
        return {'FINISHED'}

class MISC_OT_ButonThreeOperator(Operator):
    bl_idname = "scene.buttonthree_operator"
    bl_label = "Add-On Function 2"

    def execute(self, context):
        machine.state = nextState(machine.state)
        return {'FINISHED'}

machine = ButtonMachine(Choice.One)

states = {
    Choice.One : Transition("- 1 -", "scene.buttonone_operator", Choice.Two),
    Choice.Two : Transition("- 2 -", "scene.buttontwo_operator", Choice.Three),
    Choice.Three : Transition("- 3 -", "scene.buttonthree_operator", Choice.One),
}

class MISC_PT_TestPanel(Panel):
    bl_label = "Test Panel"
    bl_space_type = 'VIEW_3D'
    bl_region_type = 'UI'

    def draw(self, context):
        currentState = states.get(machine.state)
        if currentState:
            self.layout.label(text=currentState.displayText)
            self.layout.separator_spacer
            self.layout.operator(currentState.stateOperator)
            nextState = currentState.nextState
        else:
            self.layout.label(text="lost")

def register():
    bpy.utils.register_class(MISC_OT_ButonOneOperator)
    bpy.utils.register_class(MISC_OT_ButonTwoOperator)
    bpy.utils.register_class(MISC_OT_ButonThreeOperator)
    bpy.utils.register_class(MISC_PT_TestPanel)

def unregister():
    bpy.utils.unregister_class(MISC_OT_ButonOneOperator)
    bpy.utils.unregister_class(MISC_OT_ButonTwoOperator)
    bpy.utils.unregister_class(MISC_OT_ButonThreeOperator)
    bpy.utils.unregister_class(MISC_PT_TestPanel)

if __name__ == "__main__":
    register()