text:
Should I just quit Blender when after two weeks of learning and watching tutorials I cannot model anything?
I really wanted to start with Blender a long time ago but I was addicted to games and I didn't have enough time. Now, I do have time and I need to know Blender to get onto University so I've tried to dive right into it.
I have been watching videos and recreating the things that the people were doing. I really enjoyed it but now, when I wanted to do something on my own, I feel like I forget everything and the things I've learned are just gone.
I wanted to model but everyone just keeps talking about Mesh and how to add stuff but, at the end of the day, I am just not able to model anything. I only know how to add things. But when I am trying to model things, it always looks like some kind of spaceship.
I hope you know about something that could help me. I tried CG Cookie and the tutorials from Blender Guru, and some other individuals, but it's basically all the same. I even memorized like 50 Blender shortcuts but I still feel like I am unable to create anything.

My 2c.. Don't go over the top memorizing shortcuts to begin with .. there's UI for everything. The shortcuts you use most will memorize themselves when you're working fast enough for the UI to get annoying. There are a lot of shortcuts I can't remember.. but my fingers can.

I'm a year and half into Blender, still consider myself a beginner and struggling with many aspects of the software. Don't quit, Blender isn't the easiest soft to learn, but it is immensely powerful. It's a long-term project to learn how to use it and model anything, not to mention texturing and animation and fluid simulation and such. Go step by step, slowly, look at the links on the answer below, and don't worry about shortcuts, you'll learn and remind them as you go.

I'd advise to go with as many video tutorials as possible while following them in Blender to practice. After some time try to redo what they are doing (scroll a tutorial where you see a mesh part for example) and try to model it without tutorial. Put certain tasks and make yourself a goal to finish them. After yet some time try to model something simple each day, just from images around.

I don't memorise 50 shortcut keys. Whenever I get stuck for shortcuts, I use cheat sheets on my vintage iPad 10.1 that stands beside my monitor. I also keep scrapbooks on Blender tutorials and tips on that tablet. Scrapbooks help me learn Blender. https://docs.google.com/presentation/d/1MO11ucFLnwKzxjPKmLy4dfqMlQjJR1S9wHt1yB61Eqg/

It took quite a while for me to feel like I could make my own shapes. Don't give up! If grinding tutorials is getting old, look for tutorials on making things you're interested in making anyway (or close enough that you can try and adapt it; adapting tutorials to your own use case is an excellent way to get a feel for when to apply what techniques). As far as modeling your own things, it really helps if you've thought through the design before going into detail. Try sketching it first and building the general shape with simple cube shapes before throwing subd etc. at it

This isn't really an appropriate question for SE in my opinion.  But do you think 2 weeks is a long time?  It's not.  By a ridiculously huge margin.  If you want to model something, you need to reset your expectations about how much time it's going to take you.  Try 52 weeks.  There's a reason that art school lasts four years.  It's not just to waste your time.

Hah, it took me 2 years until very recently everything clicked.

Keep in mind that tutorials don't really give you your own workflow. Nor do they ingrain techniques that improve your workflow.  two weeks is nothing, just set small goals for yourself and try to achieve small things by learning operations and features blender has to offer. When you get more comfortable, especially with shortcuts you'll see much more progress.

My advice would be to write down everything you learn; that's how I memorized shortcuts and other tricks! The process of writing down what you learn should help to solidify the technique/shortcut in your mind. As an example, I personally use a GitHub WIKI (and the issue tracker) to record everything I learn: https://github.com/mhulse/3d-wiki ... When I take a break from Blender, I come back to my notes to remind myself about what I forgot! :)

Two weeks and you are thinking of quitting? No, no, no that will not do.
For anything even starting to be complex two weeks is just not enough time to call it quits. Learning takes time. How much time depends entirely on your effort. You have a good motivator to learn blender, to get into University. So do not loose sight of your goal.
Now how to go about that.
Stop watching tutorials. That's right, Stop watching tutorials. You said yourself that you "forget everything and the things I've learned are just gone." (That is because you never actually learned them, you just saw some guy on youtube do something). I bet you have spent a fair bit of time watching tutorials. Look at the outcome, for you it is not worth it.
This is a common problem with tutorials. We watch all these tutorials, and feel great "look at what I can do." Except if you just watch them, its nothing more then a movie. We feel like we conquered the world, but really we just sat on our butt for two hours.
So with tutorials out of the way, just make something. Start simple, such as the desk your sitting at. Yes it will be hard, your model will be pretty bad, and you will get stuck. However this is how you learn.
Ok so you are modeling, you hit a wall, no idea how to do X. Search for that thing (you very likely will get an answer from this site), then keep modeling.
It is ok to have to ask google how to do every step.
Here's the exciting part. You open blender up on day two, start by making another simple object. Say a wood stove. Now instead of having to search for everything you remembered that GG is edge slide, and why you should be moving that edge loop.

 Image from HomeDepo
Keep it up. Make something, anything every day. Keep it very simple. If you try to bite off more then you can do you will get discouraged and then it is easy to skip blender today, and down the spiral you fall.
Make a simple object everyday for a week and I guarantee you will learn more in that week then you have in all the time you spent in blender and watching tutorials up to this point.
Don't get discouraged when your models don't look like you wanted, or your renders aren't pretty. This is part of the learning process. I bet your first steps as a baby weren't too good either.
Please do not feel like you have to remember everything or every keyboard shortcut. Many times I have searched for something and found the answer, only to discover that I wrote the answer!

TLDR
Stop watching tutorials and just make stuff, mistakes included, in blender.

Exactly...I was using Blender for over a year before I ever saw a tutorial on YouTube. That was because I was working on an old desktop machine that didn't have an internet connection. I think that helped me a ton TBH.

You can't just "make stuff" in Blender without watching tutorials. I tried and failed miserably. The usability is so different to regular programs.

@ThomasWeller I beg to differ. First off what do you consider a "regular program"? Just because you know MS word does not mean you will be able to use Adobe photoshop (as an example). Every software is different.

I agree with the spirit of this answer, but I downvoted because I disagree with the notion of avoiding tutorials on principle. I agree that just watching the top search results for "learn blender" isn't the most effective way to learn, however, "making something" requires a fair bit of knowledge which isn't just going to pop into one's brain from trying very hard. So, don't watch just any tutorial. Want to make a certain model of car? Watch tutorials about making other car models, then try and adapt it, on your own, to the model you want to make. That last bit being the most important step.

Yes, give up right now.
The only person who can effectively answer this question is you.
If the guitar you were going to learn is in the back of the cupboard, or the piano is covered in dust, or... give up.
Like Hendrix makes the guitar look easy, a seasoned modeller makes modelling look simple. Frustratingly it isn't. Hendrix is often put forward as an example that mastering a skill takes 10,000 hours.
It's hat season, and wearing my amateur's  philosopher reverse-psychologist, devil's advocate hat, and for the sake of "balance" I say quit.
If however you have the desire to learn, don't accept this answer.

I agree to this. Giving up is a valid option. 3d is not for everyone. I see no logic in answers saying not to give up no matter what. They come only from one kind of people - the ones who did not give up so this is very biased. It takes a certain personality to like this whole 3d stuff. It is complex. Do you like failing? Do you like redoing things? Do you like investing hundreds of hours into something that turns out not to work and when in the end you need to redo it investing hundreds more hours of your hard work? Do you enjoy never knowing when your work is finished?.. Consider it.

If you read between the lines I'm not really saying quit... (quit asking questions like this  maybe). The included link is particularly interesting.  Mentions the retention rate of AV learning material is about 20%, lectures a lowly 5%,  Tips like Splitting a skill to learn into sub-skills,  sub-skills into sub-skills.  There is a "Learning Just Do it" sign...IMO  The little train that could is as good an answer to "I've tried should i quit?" as any.

This answer took me back 40 years, when I asked one of the local "pros" if I should quit skateboarding because I didn't manage to learn a propper Olli in five days. His answer was pretty much the same. "Yeah, give up. If you don't want to put the effort and you don't want to deal with the pain you'll fail anyway." It took me almost all Summer to learn it and then another 6 months to land it properly every single time.

We are of similar vintage, Tony Hawk

All these answers are opinionated suggestions for what works for the author of each answer. Votes do not signify what is correct, but instead just tell that the voter has the same learning style. Take inspiration, but figure out what will work for you on your own.
Let's actually address your problem and that is:

I feel like I forget everything and the things I've learned are just gone.
I (...) feel like I am unable to create anything

Pushing through, not quitting, watching tutorials, not watching tutorials - it won't solve your frustration. You need to solve how to memorize(learn) more efficiently.
My guess is you watch too many different tutorials, each on different topic. You create a short-term memory, and with next tutorial it gets overwritten.
My advise is to pick a topic (like modelling, texturing, ..) and focus on it for longer period of time, until you create long-term memory. Do not try to infuse all of the areas at once.
My second guess is that you learn inefficiently - everyone learns the best with different method:

visual people just need to see it. These are the ones that will post an answer to watch all the tutorials (like @Noelle or @RitaGeraghty).

some are hands-on, these people will advise not watching tutorials but doing exercises, more experimentation (like @David or @JakeD).

some are verbal/aural, helps them to say things out loud. Also they like to read, so written-style tutorials, suggestions of using a book (@JakeD).

The best is to combine all, but also to play to your strengths. If you figure out your style, the process will be less painful and more efficient.
All the answers that only tell you to keep going and just tell you what to do have little to no use. They are opinions of the author, it might not help you at all. Pls figure this out for yourself, only you can.
@batFINGER understands this too, his answer is more straight to the point. Maybe you should take a different path in your life and focus on something else that will fulfill you better, that won't frustrate you even when you struggle. Or maybe you are just experiencing something more complicated for the first time in your life and you are just confused Blender takes more persistence. Then keep going. Only you can decide.

Hidden in my somewhat tongue in cheek answer is the link  The Tactics for Learning Faster is IMO particularly worth looking into.

Don't quit. You are only two weeks learning Blender and that is too soon to quit. At the beginning, I had great difficulty in learning Blender, but I stayed at it and persisted. The more I persisted, the more I learned.
Persistence and patience pay off.
PLAYLISTS FOR ABSOLUTE BEGINNERS (see below)
(Some would interest intermediates as well). Some tutorials are somewhat old, but they are very useful and they can quickly pull you up on Blender. Neil Hirsig is very good. He is very thorough with teaching basics. His tutorials will shortly leave you with a swollen brain.
JcChronBlenderBasics
https://www.youtube.com/user/jchronblenderbasics
Jacob Lewis (2012) https://www.youtube.com/playlist?list=PL03BAC38A5E823407
Jacob Lewis (2014) https://www.youtube.com/playlist?list=PLrgQj91MOVfjTShOMRY8TLmkJ7OFr7bj6
Neal Hirsig
http://doug56.net/3DBlenderCourse/course-content.html

The thing is you shouldn't be watching too many tutorials. Watching tutorials makes you think you know how to do this and that. That's not always true, they can also make you lie to yourself. See you need to be thinking for yourself not just copying others. Also remember that quite many tutorials online are bad for you, theres always a danger that you pick up others bad habits. Be critical.
Tutorials should be used as a sort of a checking point. So in reality you should make a concentrated effort to do something before your about to watch a tutorial on it. This way you will be much much better equipped to understand why they did what they did.
So just do something, it will not quite be where you want to be. That's ok that is your level. Try doing something simple. Then try to figure out what your missing on. Find somebody that is really better, tell him what your aim is and ask him to give you some insight into what you should be doing.
Then consider that 2 weeks is nothing, you can not learn 3D graphics/ modelling in 2 weeks or even a month. You can only learn the basic concepts. There are a hundred things you haven't been thinking about yet. You need at minimum 6 months or a year to even begin to grasp the task at hand. Also you will not learn all of blender, its too complex for that, you can only learn a few aspects of it.

What are you trying to model? Perhaps you are trying to jump to something too hard such as a creature or a tree. Could you model a simple crate? Barrel? Wooden chair?
A barrel, e.g., could be as simple as a cylinder with a few edge loops that are scaled accordingly. If you want to get fancier, try adding some rings around it for braces (normally like 2-4). You could go further and extrude/scale on the ends to make it not perfectly flat.

I had the same issue many years ago when I went through this book (how I got started in Blender):

I did all of the modeling there, but felt like I couldn't build my own things. I think that in the end it comes down to persistence. I'd say I didn't truly get comfortable with modeling for several months (probably 3+) although that is a hard thing to know specifically. Try to learn the tools for what they actually are and what they do rather than the specific use case as in a tutorial. Don't spend your time memorizing hot keys. If you find yourself wasting time doing the same thing over and over again and trying to find it in the UI, then look up the hotkey (often just hover over it) and start using it.

The easiest things to model (at a basic level at least) are going to be things that are not very fluid/curved, so get started with objects that have simple geometry and work up from there.

i know how you feel, it took me 3 years before i got "BETTER" at blender. and i am still not that good Just keep playing with stuff and watching tutorials. Here is a tutorial that might just help https://www.youtube.com/watch?v=LgZ8kiISrjE. My thought process runs like this a bit, walk around a store, (or any were) see something you like, and think how you might model it in blender, then go online and search for  a tutorial on how to make that thing and if there are none look up reference images and and do your best and just keep trying.

If you like modelling, don't quit - if you are motivated, keep practicing and you'll get better in time.
Start with realistic goals. Take a simple object from your surroundings, something with a clearly defined geometry, like a light bulb, a screw, a hammer, a bottle, a mug full of pencils... This may seem too easy, but in reality, it's not easy at all. Try to replicate the object faithfully - from the accurate overall shape to the every minute detail you can see. Use calipers to measure the object and make your model with accurate dimensions. Start low poly, but don't stop at that. Be very thorough, almost as if you're doing it in a CAD software. Then focus on the materials and the scene, make it as good as you can, keep your standards high. Don't rush it, if necessary, spend several weeks doing a simple object, until you're happy with it. You're not a professional at this, yet, so you don't have deadlines.
Modelling without a reference object, that is from your imagination, is really difficult and you shouldn't be doing it until you're completely comfortable modelling with a reference. The problem with modelling from imagination is that you think you know how a hammer looks like, but actually, you don't. At least not in sufficient detail to be able to reproduce it faithfully. That's the same problem with drawing: the most important skill you need to develop is the ability to accurately see an object. You develop this skill by modelling with a reference.
Trying to do things that are, at present, too difficult for you, will only have an effect of discouraging you.
That said, make sure you don't get stuck in a comfort zone, doing simple objects for years and years. Make sure your next project is always more challenging than the previous ones.

If you want to do CGI, then don't give up. People say Blender is hard to learn, and I won't dispute that, but what they tend to leave out is that most things worth doing are hard to learn. Piano takes a lot of practice to master. As does drawing. Photography. (Physical) sculpting.
Two weeks is hardly enough time to learn any art with any degree of depth or complexity. Give it a good while longer. While practice may not make perfect, it does make you better.

One could argue that mastering blender needs, muxh of that photography skill and much of that drawing skill for support. So its more complex than any of the things you describe. Because its multiple different skills together.

This is indeed true. I was simply using these things as examples of "Rome wasn't built in a day" sorts of things.

Keep going! There was a long period of time for me where I felt like I was learning a lot but still couldn't functionally do anything on my own. After a long time of feeling like I wasn't getting much closer to being a functional blender user all of a sudden I was actually modeling stuff. When learning any complex program one needs to learn the way of thinking that's necessary to use the program well. You can know lots of individual things but until you start thinking about things in the right way all of the little bits of knowledge won't quite come together. Learning the way of thinking about blender just takes time interfacing with it. If you keep going you'll get to a point where things just start to make sense on a whole other level, you'll know how to think in blender and you'll be able to model things.

Never give up on what you are doing. 3D modeling isn't as easy as it seems, two weeks is just a short period to test your skills, It tooks two year for a friend of mine to make his own good model. Start by making low Polly object and scenes. Don't go for hard and real looking models then build you skills step by step, also you need maybe a good hardware too.

It took me 4 months of endless tutorials, courses, and trial and error almost daily to FINALLY feel 75% comfortable modeling things on my own. After all of that, while it felt like forever, it was actually very fast. It felt like overnight I had absorbed a lot of things I had learned. The  brain needs time to fully process new information. I often take week breaks and find that random things I didn't understand before just sort of make sense. Don't give up because it's immediately difficult. Push through and just know that even though it's hard and makes no sense in the moment, your brain is doing additional information absorbing without you actively trying. The number of times I've watched tutorials and 'learned' techniques that made NO sense, I can't count on my hands and feet combined. But when I approached another project, I magically found that something I had watched 1 month ago  in a random tutorial now makes sense and applies to what I'm doing. Keep pushing past all the hard parts, and in time they will make sense. I'm a now 6 month Blender user, went from 0 to a decent amount of knowledge that I never thought I was capable of retaining. you can do it!
BTW My first month, almost nothing made sense. Not joking, I just kept doing things and following tutorials despite understanding 10% of what I was being told/shown. Literally, its consistency and just exposing yourself to as much as you can. That's the key in the very beginning. Watch EVERYTHING you can get your hands on. I recommend purchasing a beginners intro to Blender course on Udemy, which should cover all essentials and you will understand what a mesh is, the uses of hotkeys, and other fundamentals. A course on sale which is VERY OFTEN is $10. It's worth it.

Absolutely not, you certainly shouldn't quit. I've been using Blender since it first became free, and it was a lot more convoluted back then (on obviously worse hardware); it took me a decade to get really good at it. It might have taken only a few years, but in truth, I'd been exactly where you are about a dozen times. My early models were horrifying.
Shortcuts are helpful, but they aren't an end-game solution. I suggest you think of it all as a development process. It's like learning to sculpt or draw. Every time you finish a model, look over it, itemize what you don't like about it, and figure out how to do it right. Then, try again. You need to train your instincts, too, and that takes a while.
Also, forget these guys who insist that you can learn something as vast as 3D modeling overnight, they're trying to sell you something. Even now, every single day I learn something new about that software. There will always be more to learn, and more to do. If you think of Blender as less of an opponent, and more of an adventure, then this will be a lot easier.
I wish you luck in your continued endeavors!

I will suggest you not to give up on it so fast. I use use Maya for most of my work and I had to switch to Blender , so the only thing which I did was that, I put myself into a situation where I had to model a basic Inorganic Model in 3 days and yes I also saw a few of Blender Tutorials and those 3 days of modeling kind of made me learn those shortcuts and also that modeling a simple model Boosted my confidence . So yeah just hang on there and simply enjoy. Do it your self and you'll finally reach there.


text:
How to stop TPose from being animated?
My .blend file
I have an armature that is linking to a Walk animation / action:

The problem arises when clicking play. It will start the animation from the TPose position, which causes deformation in the animation.
I've done this same exact process from exported Mixamo models where the action would automatically contour the mesh around the bones at the frame 1. However, it seems using a custom asset (model from unity's asset store or wherever) -- the TPose is still being used in the animation?

You can either remove the T pose keyframes in frame 1, and then move all keyframes 1 to the left in the dope sheet / graph editor , or use the NLA editor, and set the start frame there.  A lot of bvh files have the rest pose in frame 1 too. Not in a pos to write up a prop answer atm.

Oh, bvh files? I think that's my problem. This anim file is another .fbx that has its own armature, etc.. Ugh oh, maybe overlapping of bones? -- let me try your frame issue now

The NLA is the way to go imo as this will keep the tpose but not use it in animation.  However good NLA docs appear thin on the ground (hence this q http://blender.stackexchange.com/questions/64904/what-is-the-nla-editor-used-for)   The answer here http://blender.stackexchange.com/questions/3736/how-should-an-animated-character-be-moved-while-repeating-a-walk-cycle .. .if frame 1 in walk action was a tpose could just set the repeated NLA strip to use  frames 2 to 48 of the action.

This is kind of weird. I cannot find any TPose keyframes -- Here is my NLA Editor. It seems like the TPose anim was merged with the new animation? But wait, TPose isn't supposed to be an animation?

Hit the n key to expand the properties. something like https://i.sstatic.net/W9CqT.png  Set the Action Extents start frame to 2... as  I still think the t-pose is just frame 1 of your Walk action.

Ty again bat, unfortunately no luck :P -- but when changing the extent start frame it actually manipulates the entire animation, is this normal? Example Seems like it's all one motion. Maybe it's the just the model got exported all glitchy hm. I'm going to play around with the animation data slide now. Forgot to press n :P

Your action has the pretty much the t pose at frame 2 (the start frame) and frame 31, and doesn't appear to be a walk cycle, would need to mirror it by the looks.  If you set it as the action in action editor and then check it out in graph editor.

@batFINGER Hm yeah, I'm stumped lol.  Thanks for your help thus far though, most likely me not doing directions correctly. Fairly new to blender, will re-do the steps. :)

Did you guys even looked at @NiCk Newman file? The supposed T-pose is all over the animation. This animation starts from standard T-pose and continues with arms higher, plus it's only 1 half of a walk cycle. The way to fix it would be to copy all local X and Y values for all hands bones from frame 4 to frames 1-3, delete frames 26-28, duplicate 1-3 and place them instead of 26-28. Then copy pose and paste X flipped for every frame to make second half of the walk cycle. But it would need renaming all bones first, cause they don't have R. L., so Blender wouldn't copy-paste pose correctly.

@Mzidare Hmm. I think I'm doing this wrong or have a distorted .fbx file. Because the character comes with 10 + of these .fbx files which are all at different animations with no mesh. I need to apply the animation through the action editor above. I think something else inherently is going wrong that is a simple fix. I've done this exact same thing with mixamo models and it works fine. The TPose is still there but only when switched to Pose mode. Animating though, the TPose is not included, but on these models they are. Maybe how the author exported them is the culprit?

This is weird. Animation on the Armature and Walk are exactly the same, and yet Armature behaves differently. First time see something like this.

source: Stack Exchange

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

sort: votes


text:
Calculate surface area of each material?
How to find the surface area of different parts of a mesh depending on the materials assigned with python?

Extending the answer from surface area of a mesh using Python code in Blender
import bpy
import bmesh

#active object
obj = bpy.context.active_object
# bmesh of active object
bm = bmesh.new()
bm.from_mesh(obj.data)
#material slots
for i, slot in enumerate(obj.material_slots):
    area = sum(f.calc_area() for f in bm.faces
               if f.material_index == i)
    print("Material %d Area %.4f" % (i, area))

bm.free()

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


text:
Blender how to periodically reload file (python)
I'm trying to write script that will automatically reload file every few seconds. In order to do that I wrote following plugin:
bl_info = {"name": "[PonyKart] Auto scene update", "category": "Scene"}

import bpy
import threading

DELAY=30
timer=None

def reloader():
    print("Updating")
    bpy.ops.wm.save_reload()

def register():
    print("Timer registered")
    timer=threading.Timer(DELAY,reloader)
    timer.start()

def unregister():
    print("Timer cancelled")
    timer.cancel()

But while it indeed does save file properly, it crashes Blender after doing so (I so i think it crashes when Blender opens file)
Just for reference here is code responsible for save_reload from amaranth plugin:
"""Save and Reload the current blend file"""
bl_idname = "wm.save_reload"
bl_label = "Save & Reload"

def save_reload(self, context, path):
    if not path:
        bpy.ops.wm.save_as_mainfile("INVOKE_AREA")
        return
    bpy.ops.wm.save_mainfile()
    self.report({"INFO"}, "Saved & Reloaded")
    bpy.ops.wm.open_mainfile("EXEC_DEFAULT", filepath=path)

def execute(self, context):
    path = bpy.data.filepath
    self.save_reload(context, path)
    return {"FINISHED"}

I'm trying to allow online collaboration on single file. When person A works on file a.blend and person B on file b.blend and they cross-link each others grouped objects (lets say personA_group and personB_group) then with periodic file reaload users can get updated info on scene. Maybe it's not super realtime, but it works and uses relatively stable Blender mechanics.
I know there's verse and I know it doesn't work. Apart from spending like days trying to set it up after I managed to do it it crashes every few minutes and glitches as hell. It's so extremely unstable on hi-poly meshes that it's unusable. Also requires high bandwidth while method above (if we enable Blender file compression) requires only sending few MB file (usually around 1-2) over network every lets say 60 sec. It's possible to implement such mechanics using samba share. According to initial tests file reload over our samba share takes around 3-4 seconds using awfully slow connection so it's usable.

hard to tell what's going wrong, possibly delay is too short, try if this happens with large delay. but could you add some information on why you do it??

updated. 30 secons is quite big interval also I tried just manually creating thread from Blender console and the same happens - it crashes. Several methods behave weird when launched in separate thread - .quit_blender() also doesn't work. I tried to import bpy inside this callback method but it doesn't help either

Quote from the api documentation

Python threading with Blender only works properly when the threads finish up before the script does

There are two ways i know of to periodically run python code:
Register a handler for scene_update_post:
import bpy
import time

t = [0.0] * 3
t[0] = time.time()
handles = bpy.app.handlers.scene_update_post

@persistent
def on_scene_update(scene):
    t[1] = time.time()
    t[2]+= t[1] - t[0]
    t[0] = t[1]
    print("Time elapsed %f" % t[2])

    if t[2] > 20.0:
        handles.remove(on_scene_update)

handles.append(on_scene_update)

Use a modal operator (in this case the code only runs when the user interacts with blender):
import bpy
import time

class OT_INFO_time_elapsed(bpy.types.Operator):
    bl_idname = "info.time_elapsed"
    bl_label = "Print elapsed time to the console"
    bl_options = set()

    def invoke(self, context, event):
        self.current = time.time()
        self.prev = self.current
        self.elapsed = 0.0
        context.window_manager.modal_handler_add(self)
        return {'RUNNING_MODAL'}

    def modal(self, context, event):
        self.current = time.time()
        self.elapsed += self.current - self.prev
        self.prev = self.current
        print("Time elapsed: %f" % self.elapsed)
        return {'PASS_THROUGH'}

def register():
    bpy.utils.register_class(OT_INFO_time_elapsed)

def unregister():
    bpy.utils.unregister_class(OT_INFO_time_elapsed)

if __name__ == "__main__":
    register()

Since you intend to reload the file only the handler using the @persistent decorator will work.

so if i'd like to use first variant - I should put save_reload() after handles.remove(...) right? then it'll reload file after user updates scene AND required time elapsed?

I'm getting persistent is not defined

after importing @persistent this first variant also crashes blender. Exactly in the same way as thread. But modal operator does not and works properly so I think I have to use this method.


text:
Animated objects not consistently making contact with rigid body physics objects
I have a scene of numerous objects ("triggers") arranged on a path that are animated to ride on a twisting conveyor belt.  Suspended over the belt, there is a rigid body physics lever that is supposed to rotate on it's hinge whenever a passing trigger object makes contact, which then causes a mallet to swing that is connected to the lever via a rigid body spring constraint.
The problem is that the lever rarely reacts when a trigger makes contact.   I have tried changing the sensitivity margin settings of both the lever and each trigger, but this has yielded hard to reproduce results.  I have checked my normals, scale, etc.  I have increased the Rigid Body World steps per second.  I was able to fiddle with settings on the object physics properties, but could only get one of the triggers to move the lever; but after saving and then re-opening the blend file, the previously working trigger failed to work again!
In the screen shot, you can see the triggers distributed along the spiral conveyor, with an example trigger labled "X" (that will make contact with the lever when the animation starts).  The curving arrow illustrates the direction of travel of the triggers (which travel at a steady velocity).  The lever/mallet contraption is suspended over the triggers.
I would very much appreciate any suggestions as to what might be the issue.
Here is my blend file: https://drive.google.com/file/d/0B8euJ49ta_XTUFRnT2xTdTlZOEk/view?usp=sharing

----- Updated ------
I created a simplified setup to figure this out, and I think that I am zeroing in, but not there yet.
I placed a simple spinning paddle wheel object under the lever.  Eight paddles, with seven that are 0.05 blender units thick, and one paddle that is about 0.15 units thick. The tips of the paddles are about 9 blender units apart.  I set the sensitivity margins of all physics objects to default 0.04.
The speed of the paddles, and the thickness of the paddles seem to make a difference.  If I set the rate of spin down to a 2 second interval per paddle, the lever responds consistently to each paddle.  If I speed up the paddle wheel, to about one second paddle spacing, then the lever hits success become variable: completely missing one third, slightly twitching for a third, and the final third are hit solidly.
At a midway speed setting of 1.5 seconds per paddle, I see an improvement over the 1 second spacing results.  What I also notice at this speed is that the thicker paddle has the best chance (but not 100%) of moving the lever. When it does move the lever, the thicker paddle also forces the lever to deflect further than the thinner paddles deflect the lever.
I hope these further clues help to find a solution.

In the 6 weeks since I posted this question, I have found solutions and/or work-arounds for the problem.
Here are the relevant points that contributed to the fix:
1) The objects that sit on the conveyor belt were actually imported from an OBJ file that I built outside of Blender.  Independent of my physics issues, I found that these objects were not rendering correctly. The issues seem to be related to normals being strangely wrong. Other users have also noted that OBJ imported objects have normals issues in Blender. I did a bulk swap-out of these imported objects using Ctrl-L Object Data, with a Blender-modeled object. This fixed my render issues.  Was this OBJ issue impacting physics also?  Perhaps.
2) The objects on the conveyor belt each have a Curve Modifier, and animation is done by key-framing the location of one of the objects that is the parent of the other objects on the conveyor belt.  The fix involved creating a set of non-rendered objects that move on a plane in concert with the objects on the belt. These super-simplified "ghost" objects are setup with rigid body physics, and their only purpose is to trigger the mallets.  I was fortunate that all of the mallets are on the same plane.  I removed physics from the belt-mounted objects.  This did the trick!!  My observation is that the critical difference is that not using a curve modifier on objects that need to be part of the physics was the break-through that I needed.
3) Other lessons learned (painfully):
a) I accidentally changed the scene physics speed from 1.0 to 0.1.  This caused everything to react very slowly which took me a while to find the root cause, as I was in the midst of tweaking various rigid body parameters and constraints.
b) Baking - Once I did a full bake on all frames (it took two hours), the scene simulations were much smoother.


text:
Why hair particles not showing the result
Im making a grass compound wall. I have a plane and given green color and added the hair particles default settings.

Default hair particle

Press shift+z to render the hair particles showing rectangular shapes and not hairs. I want to have grass effect.
Hair showing rectangular shapes

Any suggestion or help why the hair particles showing the rectangular shapes other than hair particles.

In the very bottom of the Particle Settings you will see a section called Cycles Hair Settings. Change the 3 options:

Root
Tip
Scaling

These should make your hair thinner to your choice.
Settings section:

i have attach the file it has same settings as shown above yet to its having triangular shape

Use the root setting, and note that they will always stay triangular. Just the base width can be changed.

I have scale down the root to 0.1 and it work. Thanks

No Problems, glad I could help

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


text:
Normal map problems
When I bake the normal map, it gives me the shading artifacts from the low poly mesh.
I tried countless times, but I can't find out what is wrong. Does anyone know what is going on?
Here are some photos, thanks in advance.

The reason that the lighting looks strange is that the low-poly model uses triangles instead of quads. When using smooth shading together with the triangle-based mesh, blender has trouble interpolating the normals.
The fastest solution but maybe not the best would be to simply use flat shading on the low-poly mesh instead of smooth shading.
Ideally, you would want the low-poly mesh to be made of quads. The practice of making a low-poly quad model from a high-poly model is known as retopologizing, and there are tons of tutorials out there on how to do it. This video from CGMatter shows an easy way to do it automatically. Your high-poly mesh seems to already have good topology (i.e. quads), so another option would be to simply make a copy of the high-poly mesh and dissolve some of the edge loops.

The low poly mesh typology is like that because I made it for games, the problem still persists with simple meshes that have all quads

It seems like the baking isn't the problem, but the way the smooth shading interpolates between the normals of the different faces. When there's less geometry to work with (even if it's quads), as seen in your third image, the interpolation is generally going to look worse. You can fix this by adding more geometry around the edges, (adding loop cuts for instance), or by using flat shading instead of smooth.

Thanks, now it's working a little better It still has some problems, but it's bearable, by the way, this problem didn't appear when I baked some normal maps for testing.

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


text:
How to Export Render As Video
I made a small animation. Very simple, just a floating cube and a color changing light. After fighting a bit with key frames it was time to render, I realized I have no idea how to export this.
How do I export the video?

You can start by reading the doc : https://docs.blender.org/manual/en/dev/render/output/index.html If you've gotr any specific question after that, feel free to ask it.

in my opinion the basic format is Properties panel > Output > Output, File Format > FFmpeg, Encoding > Container > Mpeg4, and in Properties panel > Render > Color Management > View Transform > Standard. Now it's also good to choose File Format > PNG, then import all the images into the video editor.

I'd recommend render to OpenEXR and compile the resulting image sequence using ffmpeg or the VSE: https://blender.stackexchange.com/questions/52230/how-to-convert-image-sequence-to-video-using-the-vse

@brockmann is right - Render all single frames as EXR and then compile into video later. Only ever render directly to video if you have very short sequences. Why? If you render single frames and your computer crashes, you can restart the rendering from there and lose nothing. If you render directly to video and something bad happens before completion, you have to start from the beginning and may lose hours and hours of precious render time!


text:
How do I combine mesh layers?
How do I combine one mesh layer into another mesh layer in Blender version 2.81a?
I  do not know the command to do this.

Perhaps you mean joining objects? If so, then read this question: How do I join two separate objects so I can edit them as one mesh?

Got it. Typed ctrl+J and it worked. Learning the basics. So far so good. Thankyou for your help


text:
How do i make a flat circle
I need to make a flat circle as a floor for one of my objects, but I don't know how to make a circle.
I have tried different methods, but they don't work.
I have tried to make a mesh circle but nothing comes there, so can anyone help me?

The easy way to create a circle (floor) is to add a circle object under Add > Mesh > Circle. Then tab into Edit Mode and press F to fill in a face.

One last question is there any way to make it bigger on the z axis so it isnt flat but a little bit thicker?

yeah ! go to edit mode and select the top face of the plane ,E to extrude and z to z axis ( but u should make sure that the plane is facing z axis ) , and extrude as ur wish :-)

Add mesh circle, set the faces from ngon to triangles. Also make sure that you are NOT in wireframe. The circle should show in viewport + final render + viewport render. If it does not, please tell me! I would be happy to help further.
Here's a picture of setting this:
Before:  After
Here are pictures of the circle before and after:

After:

I am so new to blender that I don't know where that "faces" is can you maybe take a screenshot and show me?

Here is another way to create a circular plane with (sort of) uniform vertices.
This may be useful in case you are not satisfied with either the "triangle fan" mesh generated by Add -> Mesh -> Circle -> (Fill option) or the "zigzag" mesh generated by Mesh Circle -> (Edit Mode) -> Face fill

Add -> Mesh -> Plane
Add -> Mesh -> Cylinder
Move them to intersect
Boolean difference modifier on the Plane, choose Cylinder as operand object
Apply modifier

The result:

particularly useful for eg. Cloth simulations


text:
Weird problem with my mesh collapsing in on itself when posed at certain angles
I'm a bit new when it comes to Blender, so I'm hoping this an easy fix.
I was applying the skin weights to my character, when I noticed this problem where my character's mesh will collapse in on itself if they are leaning to their right. If they lean to the left, it jumps back to normal.
I checked to see if any other bones were influencing that specific region, but as far as I can tell, the torso bone is the only bone affecting that part of the mesh. This is the only bone that seems to be having the issue.
I used the Rigify plugin to make the rig.


text:
Linking transformation but not other data (ex. Modifiers) in two objects
I need to link only the transformation of two objects, but no other properties.
I need to create a hollow cylinder. The catch? It must be made out of cuboid objects and only with rotations 22.5 degrees at a time. This is because I am making this for a Minecraft resource pack, and these criteria are part of the requirements for the Minecraft Exporter I am using. I came up with an idea. I used an empty with a slab I very roughly transform scaled. I copied the transformation info from the slab to the empty, altered the empty so it was 22.5 degrees off in rotation and a bit to the side and down, and then set up an array mod on the slab relative to the empty. This created a barrel.
The problem? Any time I scaled the barrel, the empty had different data, and so the barrel was destroyed in a variety of interesting ways. I tried making the empty a child of the barrel, but then the weirdest thing happened. At first it worked, but if I needed to edit the actual transformation of the barrel slab (ex. to make the barrel thicker), it seemed to reload the parent-child relationship, and give the empty the array modifier. I tried putting both the barrel and empty under the same parent (another empty), which worked but any time I had to rescale the whole thing, I had to select the empty in the hierarchy, not in the viewport, because selecting it in the viewport selected the barrel slab and not the parent empty. So I need to link the transformation of the slab and the empty, but in a way that does not link all properties of the parent.

For arrays from object offset, parent the object to the array.  Empties cannot have modifiers of any kind, so I'm not sure what you're talking about with it acquiring the array.  This is likely a misinterpretation of something, but if it's not, then it's a bizarre bug.  A video of the problem, or a file with explicit instructions to recreate, would be necessary to answer in more detail.

Selecting the empty will not select the barrel.  Regardless of selection in viewport or outliner.  I wish there was an interface to make Blender behave like you describe, it would be useful for a few specialist things.  Again, I suspect you're misinterpreting something, and video or file+instruction would be necessary to give more detail.

To answer the explicit question, for perfect linking of transformation data, use object constraints.  "Copy transforms" copies all data.  You also have "copy position", "copy rotation", "copy scale", all pretty self explanatory.  Generally, you'd be using these world->world space, but there are times that you could parent an object to an empty and use local space coordinates to achieve other effects.  (However, again, I strongly suspect that there's some misinterpretation of what Blender's doing here, and even though it answers your explicit question, I doubt that it will do what you expect it to.)

Thank you! This is exactly the answer I was looking for. I didn't know the answer was right in front of my eyes, but I'm not animating so I guess I wouldn't look there...  Anyway, it didn't take much to notice a empty with no modified parent doesn't even have a modifier slot. That is a weird glitch, but I guess Blender surpassed its own programming to find a way for a modded mesh to modify an empty. And when I say I couldn't select the empty in the viewport, I meant it was hard to select because the modded barrel slab was the mesh and overshadowed the empty in the viewport... Thanks again!

Wish I could upvote but I'm too low level... Blender was even smart enough to relate cloned copies with each other in the array and constraint associations!


text:
My GPU does not show up in CUDA
I have been looking around on the internet for a long while now, and I haven't gotten any info about this problem.
I have a NVIDIA GeForce GT 710 in my computer, but when I try to use it for cycles rendering, it doesn't show up in the CUDA tab at system, user preferences.
I am using Blender 2.8, if that may contribute. It just says "No compatible GPUs found for path tracing Cycles will render on the CPU"
Any help would be greatly appreciated. Thanks to those in advance.

Under Preferences > System > CUDA, does your GPU show up there, and is the tick-box checked?

If your GPU is a GT 710 and not a GT 710M, then it should be supported. Try to update your graphics driver and check if that resolves the problem. Also make sure that your operating system recognizes the GPU, e.g. by checking dxdiag on Windows.


text:
get position difference of the object from current frame and previous frame through python
I have an animated object
I am searching a way to calculate the difference in the position of the object from current frame and a previous frame and if the difference is not big enough i want to keep previous position
cant find a way to do it :(

this should help you: https://blender.stackexchange.com/questions/106574/read-value-from-an-fcurve-at-specific-frames

thank you Chris


text:
How to convert a point 's location to a vector
How can I convert a point's position to a vector which I can then use as the endpoint for an arc node?
I'm using the latest version of blender.
First time using Stack Exchange, so let me know if you need more info.
Clarification:
Is there an ideal way to extract the Position of a vertice/point into a usable vector to start a "Mesh Line" or "Arc" from?

It is not quite clear what exactly you mean. The position of a point is a vector. If you are asking how to transfer the position of a certain point, try the node Sample Index.

Hey there, I'm trying to use the Sample Index node, but it's not  working.

If you want to sample the position of the point with the index $1$, you would of course have to put the node Position into the input Value of the node Sample Index, because otherwise nothing would be sampled.

Thank you @quellenform ! It was the Position Node that i was missing.


text:
How to keep menus up as persistant toolboxes
Maya 2017 had a feature where you could "tear off" any program menu, and it then acts as a persistant little window that made using tools easier.
Is there any way to get the same fuctionality in Blender? I'm having trouble finding exactly what I'm looking for.
This following part is answered. [ Shift + A ] > [ S ] Sounds like an elegant enough shortcut for me to use for this specific purpose

My current need is in geometry nodes. I want have the "add nodes" menu
open in a window instead of needing to right click and fiddle through
menus.

Just a stupid question: What would be the advantage compared to the key combination Shift+A? That would just waste screen space, wouldn't it?

Shift + A and then you could press S and type the name of the action that you need

This isn't possible in Blender, it was explicitely designed that way by the developers : No overlapping panels

The Add menu has a lot of subsections - do you want them all to be expanded? What a mess... and if you just have the top menu I could imagine it's not much easier to find everything from there if you don't know exactly where to look. Instead of the Add menu you could also press F3 and start typing what you are looking for, the search will narrow down the results the more you type in. Nodes you need more often you could right-click and either add them to the Quick Favourites or assign a shortcut to them.

Seems I was a bit bored in my lunch break, so I just looked through the menu... there are 227 nodes in my current version 3.5.1 that can be added (actually just 225 because Group Input and Group Output are both twice in there), and you want a permanent panel showing them all so you don't have to "fiddle through menus"?

Sounds like the answer is no.
For the way my brain works, having a scrollable list of the nodes that could be dragged and dropped would help me think when I'm working.
However, thanks for the tips about [ Shift+A ] > [ S ] I'll try and make that a habit
Cheers, folks!


text:
cloth simulation
I am currently trying an animation that pulls out paper out of the box.
As a paper, I used a plane and applyed cloth simulation. To move it, I've made several hooks and attached a key to it but the cloth doesn't seem to follow the hook.
Can anybody help please? File is below.
https://drive.google.com/file/d/15xDT-3WuYFn1ia4JX9qpo0e1KIIzdxx8/view?usp=sharing

i don't see any hooks modifier in your file!?

Sorry I may have attached the wrong file.
I changed the URL, could you check please?

Hi Please use a title that reflects the content of the question. It should be descriptive but succinct, unique and identifying, summarizing the issue so that users can at a glance understand what your post is about. Use the [edit] link below your post and avoid anything not strictly essential to the post. Remember, your title is the first thing potential visitors will see, and makes your question findable for future users. See "What is the problem with posting an image or link and asking “How do I do this?""

you just forgot to set the pin group "pin" here:

result:


text:
Mesh comes off when moving bones
I am a beginner of rigging bones and have a problem I've been working on for 2days now.I am currently trying make an animation that moves as though a tranparent person is hanging it on his body. So first I tried rigging the object and then applying rigid body using "rigid body gen" addon. The addon helped me wiggle the strings of the bag but when I try move the bag body(the bone I named "spineDown"), the strings(named bones "legRF" "legRB" "legLF" "legLB") comes off and will not follow the body.
I am assuming that there is a parenting problem..? Or is there a way to attach the meshes?
Here is the file. Could somebody help please?
https://www.dropbox.com/s/eivg9czy5xisa8o/bagwalking_20230620.blend?dl=0

1) Inspection
If you look in the outliner, you can see that your "leg" bones are not parented to spineDown:

But constraint icon shows up on them. And if we look which constraints are these, we can see some of them constrained as Child Of other leg bones, and those bones themselves constrained Child Of "rbg...." mesh objects.
Since they are the one driving the movement of the bones, I guess they are the ones carrying the Rigid Body simulation. A quick look in the Properties Editor > Physics Properties with one of the mesh objects selected confirms that:

Empties also have these. Plus the relationship dashed lines in the viewport indicate they are somehow children of the "spineDown.001" mesh object. Which is also confirmed by their physics properties:

Noting, "spineDown.001" is constrained Child Of your armature object.
2) Diagnosis
I guess all the objects you have inside the "bag" collection were generated by the "rigid body gen" addon. But there are a couple issues:

They are parented to your armature object, not to your "spineDown" bone.
"spineDown.001" is constrained Child Of your armature.

3) Solution

in the outliner, select the first object in the bag collection, then hold shift and click the last object of that collection to select all the objects in between.
In the viewport, hold ⇧ Shift and select the armature. Release ⇧ Shift. Switch to Pose Mode, and select the spineDown bone.
With your mouse in the viewport: ⎈ CtrlP > Set Parent To Bone Relative (should be the last option)
Since "spineDown.001" is now parented to the "spineDown" bone, the constraint is redundant. Select "spineDown.001" in the bag collection, and delete the constraints in Properties editor > Constraints tab.

4) Result


text:
Why is there some twist existed on my skeleton for 0 rotation?
I have generated a bvh file with manually defined skeleton. I find some degree of bone twist exists on every frame. Even when all Euler angles are set as 0, the visualization still exhibits some weird bone twists. I find giving the standard skeleton a global rotation would change the alignment in the visualization. Does it mean the skeleton I defined is done in a wrong way?
I'd like to make it look like figure 2. The problematic bvh file are here, f1.bvh is a short version with a single frame; the other is the full animation I generated with deep learning.
I have tried to align the bone to a armature axis as @moonboots suggests like in figure 3 (thanks!) However, doing this also changes my motion in figure 4. Selected is my original pose, and I have aligned two legs and one arm.
Edit: OK, after I global rotate the entire standard skeleton with script, everything seems fine now. figure 5. The modified file is walk3_subject5_out_100_2_fix_v2.bvh. Still have no clue why would that remove the twist.

I can't import the walk bvh, but the default armature has its bone incorrectly rotated, maybe it's your problem here, you need to align the bones with the armature axis, for example select the legs and Shift N > Global X Axis

@moonboots Hi, thank you very much for the fast response! I have updated my file, hope this time it can be loaded correctly. Anyway, I have followed your advice and edit the bones and align them with the armature axis.(figure3) However, It would also change the my motion data.(figure4)

Yes because the bones rotate according to their new orientation, they need to be correctly orientated from the beginning, or I may miss something...

I have rotate the entire skeleton using a global rotational matrix, making it lying on the ground (last pic). It seems it fixed the problem.

I don't quite understand to be honest. Why would each bone in skeleton of figure 3 file link has the correct orientation? Why would different global orientation cause problem in my case? Thank you for the help@moonboots

Your problem is hard to follow, and Blender Stack Exchange is not really made for complicated problems, maybe you should follow some basic tutorials about rigging, armatures and so on?

Any suggestion of basic tutorial. I am from deep learning and cs background, I have zero experience of this. Thanks@moonboots

Darrin Lile and Sebastian Lague have made good tutos on rigging imho, it was for 2.7 but it hasn't changed a lot, maybe take a look?


text:
How to reset the center of rotation of the 3d view when it is not the center of the view
Sometimes the 3d view rotation using the 3rd mouse button starts to rotate around an unusual point that is not very convenient.  I don't know why it starts doing this, but it usually starts when I'm zoomed in on a detailed part of a model and persists even after I zoomed out.
I've tried changing the rotation style back and forth from trackball and turntable.  I've tried restarting Blender, but that doesn't really help.  My main solution to this problem has been to abandon working on the projects that this happens too, which only works because I've been lucky enough to have this happen only on projects that can be abandoned.
Is this changing of the view rotation a common occurence?  Is there a way to reset the center of rotation for the 3d view?

Is the 3d cursor in the middle of the scene? Try using Shift + C to reset it and try again.

To re-center the 3D view pivot to a more convenient point, select a vertex (or series of vertices) near the area you're working on and, in Edit Mode, hit Numpad . (the period key on the number pad). The view will now rotate around said element, avoiding those situations where it's nearly impossible to work on an area because you can't get a good look at it (when it rotates too far for you to focus on that area easily). You can also use this shortcut (called "View Selected" in the keymap) in Object Mode to fit the active object in the view and pivot around it.
You'll have to do this every so often as the geometry of your object changes (or the view behavior otherwise gets weird). I recommend using "Rotate Around Selection" under View Manipulation in File > User Preferences > Interface because it makes rotation behavior more predictable.
This shortcut is also helpful when dealing with this problem:Ctrl + Shift + MMB  (Dolly View) changes the view center (which the API calls the "Location" component of the 3D view), which is the source of the problem.
Also read this, it explains how the 3D view works and why your problem occurs (Credit to iKlsR for the link):
Why does the zoom sometimes stop at a point?

This seemed to do the trick!  I also found that when I got really frustrated, if I destroyed the 3d view window and then recreated it, that seemed to restore the proper view rotation.

Why does dollying change the orbit point? Zooming with the mouse wheel doesn't (and it has the same effect). Dollying doesn't change the orbit centre in Maya so I'm finding it very difficult to get used to.

In Blender 2.81 "Rotate around selection" option has been moved to Edit > Preferences > Navigation > Orbit & Pan

Since you say you tried switching the rotation modes and that didn't work and your question title speaks about resetting the rotation to the center of the view, you probably more than likely hit the . (period key) by accident (and your 3d cursor is elsewhere), this rotates around the 3d cursor. Just press , (comma) to switch back to the default.
You also say you restarted and the problem still persists, could you have also accidentally saved this as the default? Several possibilities here as this sounds like a localized problem.
If all fails, I suggest restoring the factory defaults by going to File > Load Factory Settings. Then once it has been reset, use Ctrl + U to save this as the new fresh default.
Also see possibly related

Why does the zoom sometimes stop at a point?
What is the difference between the trackball and turntable style view modes?
How to lock the view to prevent rotation of the view camera?
How do I center the view at the origin without moving the 3D cursor?

I could be wrong in respect to the problem but this is how I understand it from how it's phrased. Let me know so I can bin or keep the answer.

http://blender.stackexchange.com/questions/386/how-do-i-center-the-view-at-the-origin-without-moving-the-3d-cursor also has lots of relevant information

. and , change the center of rotation for rotating objects, but not for rotating the 3D view itself.  I tried to reload the preferences, but it didn't work. Erics solution below seemed to work, though.

@Jason I am pretty sure, what he has in his answer is the same thing I have here.. ;) You were probably after the Rotate around Selection feature tho.

@iKlsR Yes, I believe you're talking about a different problem. Hitting just the period key changes the transform pivot, not the "location" component of the 3D view (which the API describes as the 3D view pivot). But, the links you provided were very helpful, some of these things I didn't know until I read through that link you provided.

@Eric np, I was trying to take into account if he had moved the 3d cursor. Good insight btw.

Go to View -> Align View and choose the appropriate option. If your object is at the origin then "Center Cursor and View All" works best

Maybe setting Auto Depth, pictured below, can help. Per its tooltip, Auto Depth will "use the depth under the mouse to improve view pan/rotate/zoom functionality."

A bit tricky on wireframes, but it really helped me controlling rotation pivot. Just put the mouse cursor above a surface (easier on a solid-displayed one) before rotating.
You may also want to read the discussion about zooming in perspective mode, here: Why does the zoom sometimes stop at a point?.

This didn't seem to work for my particular problem.  To be honest, I'm not really sure I understand what this option actually does, though, beyond it's tooltip's description, anyway.

My answer assumes you're using Orthographic view which is, looking at your preferred answer, not the case :D For a couple reasons, I very rarely work using Perspective view.

OMG.. I know this is super old but that was driving me NUTS! I think this is a 3DSM thing that people requested so much that they turned it on by default. BTW, it's under the Navigation tab now.

You can also set the view to rotate around the 3D cursor by using the shortcut AltHome, or AltF which also works in sculpt mode around the mouse pointer.
For extra options go to 3D view > Header > View > Align View.

I had been fighting this for some time. Like @Jason, I don't know why it ever changed to something else.  But emboldened by the answers above I went exploring.  Eventually I hit <alt> period and my 3D view snapped to attention (:-)) around the selected vertex, and a quick test of middle-mouse-button movement showed my view rotated around the selected vertex.  So I headed into User Preferences to find out what the Key Binding of <alt> period does.

So now I think my slightly better informed way of talking out my problem is that the space_data.pivot_piont was set to something I didn't want and now that's fixed!


text:
Change the number of bones in Limit Weights, in 2.7+
I'm trying to limit the number of bone-weights per vertex to 2 or 3, and there is an operator in Blender in the weight-paint mode (Tool pane) called "Limit Total". But there is no way to change the default number of 4 weights per vertex in the UI... that I can find at least. Is this a bug or omission in 2.7 or am I just UI-blind?
How to restrict vertex weights to no more than N number of Bones?
I can do it through the python console as the underlying operator has the arg "Limit=4" as default and can be changed, but it is somewhat inconvenient..

It is in the UI (you need UI glasses ) in the operator properties panel:

Aha, it was that + sign in the bottom that I had to click.. I didn't know there was a hidden options panel there as well (there already is an options panel if clicking the Options vertical tab to the left :)

Seems there is a "bug" in that the panel option for Limit Total is only folded out once you already click on it, and then it has already run the limiting, which is OK if you're going to reduce the value, but would of course destroy your weights if you're in fact going to increase the value. Just noting.. :)


text:
Changing preview animation fps
How can I change the preview FPS (the animation rate when pressing Alt+A or Play) in Blender 2.72?
It seems locked to 30 fps, so somewhere there is an option that says 30, but I've looked everywhere and can't find it. The scene is extremely simple so not locked by performance reasons.
This other question asks the same thing:
Is it possible to adjust the frame rate of viewport playback?
and the answer there was to change the rate in the Scene tab under Dimensions, but that is 24 fps currently and changing it doesn't change the preview rate.
I don't want to render and playback etc, I just want to play the animation faster in the preview window.
Thanks!

Changing the rate in the Scene tab under Dimensions changes the Preview rate for me, just like it's said in the answer you've linked.

very strange, some kind of sync problem between the viewports maybe or animation timeline? maybe you have to have the right animation timeline/editor open at the time you change the framerate under the Scene tab :) I'll go try some more....

Ok, after some more digging, I found this:
The scene tab does change the FPS, but there is some lock at 30 fps preview rate (at least on my setup) because the FPS indicator goes "red" at exactly 29.97 fps or so. It's most probably not due to scene complexity and the value is too close to 30 fps exactly to be a coincidence. Some kind of vertical sync issue?
To increase the rate anyway, the "Time Remapping" box just underneath the Frame rate box can be used, for example setting it to 100:50 will in effect make the animation twice the speed.
HOWEVER there is a bug (in 2.72) it seems that makes this time remapping not work completely smooth - the "remapped" frame numbers are shown inside the Timeline and Action editor, but the "unmapped" frame numbers are (of course) used for the keyframes (since these are not actually changed by the setting).
So, for example, if you have a 100 frames long animation setup, and you set the remapping to 100:50, you will need to change the start and end frame in the timeline to 0 and 50, or it will not loop correctly. This will show only half the range of your keyframes, since the "display frames" are now remapped compared to the "animation frames"... :/
I can post a screenshot of this if needed but it works for me (don't know if there are any hidden problems other than a display issue).


text:
Topology question regarding circular holes
Hopefully general topology questions are ok here. If not then I apologize. I'm still new and trying to focus on topology. I'm working on an insect type model (bee/wasp) and have kept it all quads but have now inserted circular holes for the legs.
My question is: if this is intended for a video game should I use n-gons to "contain" the holes and keep it low poly? Or insert edge loops to keep it all quads? Will having n-gons around the holes cause problems for texturing and animating later? Also I noticed that the edge loops I added makes the model all quads but also introduces 6 sided poles, is that bad? Did I do it incorrectly?
I've attached images with and without the edge loops. Thanks so much for any insight you can provide. I want to be confident in my topology choices.
Image without "extra loops"

Image with "extra loops" (and 6 sided poles :/)

Reference Image (still a ways to go lol)

For a game engine, use triangles. Most game engines do not support ngons anyway, and the ones that do are just converting the ngon to triangles.
In general modeling, you should try to avoid triangles and ngons (there are some cases where they are ok), however when modeling for a game, low poly takes precedent over nice topology, so triangles are normal.
In your case, even if it was not a game model, I would not want a ngon in the middle of the model. Ngons have a nasty way of deforming a model, and any ngon that is not perfectly flat will cause shading artifacts.
What is the technical difference between an Ngon and a bunch of Tri's?
When should N-Gons be used, and when shouldn't they?


text:
Need some help baking, "No active image found in material"
I followed the guide here: How do I bake a texture using Cycles bake
I unwrapped my UV, created a new image, created an Image Texture node and selected my new image with that, and hit bake. I then receive the error in the title. Here is a screenshot of my view:

I'm definitely doing something wrong, hopefully one of you can point out what that is.

You have empty material slot maybe that's the problem?

That worked! Thanks Dennis, I appreciate the answer. You can go ahead and write one and I'll mark it.

Try to go to the top of the bar and switch the cycle renders to Blender Render

For baking in cycles each material slot requires image texture in the node setup, and it looks like even if the material slot is empty. To fix the error, remove the empty material slot from the object.

Do you think this should be reported as a bug?

@RayMairlot That's quite rare for experienced user to have something like that. I dont think that will be considered as a bug because logically that's how it supposed to work.

I'm not a fan of the above comment.  You shouldn't have had to hack your way through this issue and it's unclear messaging multiple times to be able to avoid it.  Bake should either be more intelligent, or at least be a lot more clear with the error messaging.

I have the same issue, but I'm new to blender and have no idea where an empty material slot is? More help is definitely desired for newbies!

O geez that is dumb.. have to have the node with an image texture selected.. Maybe update the error comment

What is a material slot? How do I know if it's empty and how do I delete it?

For Blender beginners like me, here is a much clearer and more detailed guide:

Go to 'Shading' view
For each material used by your mesh:

Inside the side-pane, select the material
Inside the Node Editor window, create a new Image Texture node (Add > Texture > Image Texture). You literally don't have to connect this to any other nodes. Yeah I know, this is a very strange process.
In that Image Texture node, select or create a new image where the bake output will go.

If you're using multiple materials, you can re-use the same image inside their Image Texture node.

Make sure you have your mesh selected
Hit 'bake' and voila

This is way more helpful than the accepted answer. It's truly unfortunate it has so few votes.

@Matthew is right. It still feels akward doing it as a fix, but at least it is working. And the instructions are cear on this answer. Upvoted. Thank you!


text:
Rig a daz genesis character in blender
I imported a Genesis character from Daz and want to rig it with Rigify.
But when I associate the rig to the mesh I have this error:
Bone Heat Weighting: failed to find solution for one or more bones
Then when I move the control rigs the mesh is not moving together.
I tried to merge by distance the mesh but it doesn't work.

try the "scale up 10x" trick. Scale up the armature and mesh 10x, parent to with auto weights, and reset the scale. Since you have locked all UI transformations and multiple mesh parts you have to unlock the scale first or use the armature to bypass the locks.

in a nutshell: 1) generate the rig from the meta rig. 2) parent all mesh objects to the armature (rig) with just Parent To Object. 3) select the armature and scale it up by factor 10 (keys S+1+0+Enter) 4) parent meshes again to the armature, this time With Automatic Weights => no error, the mesh will shrink. 5) select armature, reset scale (Alt+S) => the model is tiny now. 6) select mesh objects and clear parent (Alt+S) => the model has normal size again. 7) Parent mesh objects to the rig one more time, this time with Empty Groups to keep the weights untouched. Done.


text:
Weird ridges/wrinkles along iPhone model
I'm new to Blender/3D design as a whole and I am getting some weird ridges in my models. I believe this happened when I beveled it. Any ideas as to what I can do smooth this out?
File: https://www.mediafire.com/file/kkr2q56rfd3x4qu/050323-Iphone.blend/file

The faces of Cube and Cube.012 are overlapping, you need to fix the problem by moving the object (or the mesh within the object) a bit on its Z axis:

Also you have overlapping vertices in Cube.012, you need to do a M > Merge by Distance.
And you have a lot of useless topology in Cube, it happened when you beveled the edge, you also beveled all these edges, which is useless and also created bad artefacts, I'm not sure how to easily dissolve these useless topology though:

Thank you so much! As a novice, this means a lot. I appreciate you looking into this for me!


text:
Blender Custom Startup template is causing my high poly mesh to become a circle
I am making a startup file to easily create tillable textures and brush alphas. To do this I create a high poly plane that has x,y tiling enabled in sculpt mode. however when I put the file in the  bl_app_templates_system and load it. the high poly plane becomes a circle that has its points distributed across the circumference. It seems that if I keep the plane below a certain threshold it will still behave as expected.
I don't know if blender has a hidden limit to how much data can be in a startup file or not. it also breaks if  use a sub-div modifier to cross the threshold. Any insight as to why this is behaving like it is would be helpful.


text:
Black render on Cycles
THIS IS NOT A DUPLICATED QUESTION
As mentioned, I have tried everything under Render result is completely blank and nothings has worked.
I'm using blender 3.0.1 to render a scene. It renders properly with both Eevee and workbench but cycles in specific (both supported and experimental) cause all rendered frames to turn out black.
It's not a problem with the scene as even in cycles it renders the objects correctly and only then turns the entire frame black at the end, regardless of output format.
I have tried every workaround I could find. No problems with the scene. Sequencer and dithering are off under post processing. All exposures are set to 1.
Is there anything else I could try or is it broken in this version?

Access to a file is going to be necessary to investigate, I think.

if you want your question reopened you need to provide a simplified blend file reproducing the problem (meaning remove evevrything in the file except the parts that cause black result) else it will remain closed.

As suggested, please provide a minimal failing file on https://blend-exchange.com/ . Then  we can reopen, and  test for solutions not appearing in the supposed duplicate.


text:
Script that will assign vertex color based on distance from cursor
my goal is to create an operator script that will add the specified color to the vertex color of the selected object based on distance (and lambert using the normals facing). this will essentially paint with a simulated point light. ideally id like to do this in vertex paint mode and just grab the current paint color. i have to figure out the falloff logic. its acting kinda wonky.
here is the script (blender 3.5):
import bpy
import mathutils

newcol = mathutils.Color([0.0, 1.0, 0.2])

# Get the active object and ensure it's a mesh
obj = bpy.context.active_object
if obj.type != 'MESH':
    raise ValueError("The active object is not a mesh")

# Get the mesh data
mesh = obj.data

# Get the 3D cursor location
cursor_location = bpy.context.scene.cursor.location

# Get the vertex color data
colattr = obj.data.color_attributes[0]

for v_index in range(len(mesh.vertices)):
    # Calculate the distance between the vertex and the cursor
    distance = (mesh.vertices[v_index].co - cursor_location).length

    # Apply quadratic falloff
    falloff = 1 - (distance / 2) ** 2  # Adjust the divisor for desired falloff range

    # Multiply the float color values by the falloff and add it to the current color
    colattr.data[v_index].color[0] += newcol.r
    colattr.data[v_index].color[1] += newcol.g
    colattr.data[v_index].color[2] += newcol.b

# Update the mesh
mesh.update()

right now its assigning color, just not correctly falling off

Ok so it turns out my vertex color channel is in the face corner domain. I just need to figure out how to iterate through faces to do this properly

You can either store it into the vertex domain or face corner domain.

Yes, turns out it this code only works with Vertex Domain color channels.

You can change the domain in the UI.

again, the original code works. it is the final code. it was giving me issues due to the domain of the vertex color channel. if you use face corner domain, you would need different code. that i do not know.

@robin-betts marked my previous answer as a comment. this is incorrect. the answer to my issue was indeed that the vertex color channel needs to be in the vertex domain. that is why the falloff logic was not working. Once you add a vertex domain channel, this code works.

To be useful to others, you may post your final code so other people may benefit from it

where's the code


text:
Get Blender X,Y,Z and Bounding Box with script
I need to get the x,y,z values of an object as well as the bounding box through a script. So far I have the area and volume with the following code:
bm = bmesh.new()
bm.from_object(bpy.context.object, bpy.context.scene)
area = str(sum(f.calc_area() for f in bm.faces))
volume = str(bm.calc_volume())

I tried something like this for the bounding box:
bb = str(bm.dimensions())

or
bb = bpy.data.objects["test2-2"].dimensions

but neither have worked. As far as the x,y,z values go I'm stumped. Please let me know if you have any suggestions.
Thanks!

I think you just need to specify which attribute to get from the dimensions (bpy.data.objects["test2-2"].dimensions.x for example)
As for location, use bpy.data.objects["test2-2"].location.z

wow, that totally makes sense, and works well. Thanks a bunch!

Wasn't sure if that's all you wanted to know - added it as an answer.

Both location and dimensions are vectors, meaning they'll return a vector of three values (x, y, z). If you want to get only one axis, use:
bpy.data.objects['object_name'].location.x
bpy.data.objects['object_name'].location.y
bpy.data.objects['object_name'].location.z

The dimensions of the bounding box of that object:
bpy.data.objects['object_name'].dimensions.x
bpy.data.objects['object_name'].dimensions.y
bpy.data.objects['object_name'].dimensions.z

You can set the values by simply using obj.location.x = 5, or if you would like to set all three axes, you can do obj.location = (1, 2, 3)

If I try to use dimension.x in a driver variable, it doesn't recognize it as a valid data path. I have to write dimensions[0] to get the x value.

To include parenting and drivers, use this for the actual object location / origin:
ob = bpy.context.object

ob.matrix_world.translation # or .to_translation()

You can get the bounding box corners Object.bound_box in object-space and multiply by Object.matrix_world for world-space:
from mathutils import Vector
bbox_corners = [ob.matrix_world @ Vector(corner) for corner in ob.bound_box]
# bbox_corners = [ob.matrix_world * Vector(corner) for corner in ob.bound_box]  # Use this in V2.79 or older

Note that the bounding box is not axis aligned.

Starting from 2.8 TypeError: Element-wise multiplication: not supported between 'Matrix' and 'Vector' types: needs to be: bbox_corners = [ob.matrix_world @ Vector(corner) for corner in ob.bound_box]

@oneiros I also encountered this error did you find any solution for it?

@AvivSham it's right there: bbox_corners = [ob.matrix_world @ Vector(corner) for corner in ob.bound_box] (change the asterisk * to an at symbol @)

Could you give links to explanations why is Greg Zahl's answer is incomplete? Not sure what parenting or drivers are, and how they impact the results his code gives

dimensions is based on the object bounds which you can visualize using the Properties editor: Object > Viewport Display > Bounds (type Box). However, if you want to know the dimensions in world space (global instead of local), you need to calculate that yourself. If you parent an object to another one, it follows its transformations while still having its own transforms relative to the parent object. Rotating the parent doesn't change the local dimensions of a child object but it may affect the global dimensions.


text:
Black Images when rendering: image editor does not work
My rendered 3D model is correct, light and camera are on and it displays nicely in the rendering mode in 3D view.
However, when I hit the render button the rendered image is black. Here is a screenshot.

Do you have any idea about what could cause this problem?
Anyway thanks a lot!
Cheers

Could it be that you didn't unwrap your model or forgot to assign the textures? For other issues you should consider to upload the .blend file (e.g. http://pasteall.org/blend/ and add a link here).


text:
Snap face to grid
I need to move an entire object, so that one of the faces is exactly at Z=0. What is the best way to do this? Basically, if I could select Grid or 3D Cursor in the Snap To menu, that would be perfect:

My current workaround is to select the face, copy its Z coordinate, select all, move it all down by that same amount. Is there a faster way?

You can snap to the grid or the cursor by pressing ShiftS, however I'm not sure that is the fastest way in this case.
Method 1
Transform snapping and a guiding plane.

Add a plane underneath the object

Enable Face Snapping:

Press GZ0 with the object selected and your cursor over the plane:

Pros:

Works in object mode and edit mode

Cons:

Requires a new object.

May require positioning/snapping the 3D cursor (ShiftS) before hand (to make sure the plane is in the right place).

Method 2
Positioning and snapping to the 3D cursor with ShiftS.

Snap cursor to face (select face in edit mode and press ShiftS> Cursor to Selected)

Snap the object origin to the 3D cursor (switch to object mode and press CtrlShiftAltC> Origin to Cursor)

Snap the 3D cursor to where you want the face to go (if you want it to go straight down, you can set the Z position of the cursor in 3D view > Tool Shelf (N) > 3D cursor. In the gif I snapped it to the center with ShiftS, however it's slightly fewer clicks to use ShiftC. Note that ShiftC will also center the view between all visible objects)

Snap the object to cursor (ShiftS> Selected to cursor)

Cons:

Requires repositioning of object origin

Only works in object mode (ShiftS works based on the pivot point, so in this case the center of the object would be snapped to the cursor)

Method 3
Snap to grid with ShiftS, then increment snap to align with the gird floor.
Note that Snap to Grid will snap to a 3D grid, not the grid floor (though the grid floor is a 2D representation of the same grid which is used for snapping)

Cons:

Will snap object to align with grid on X and Y as well.

For method 3 you can hold CTRL key to snap on grid while moving the object.

@Polosson That's actually what I did (you'll notice that the snapping/magnet icon is disabled). Holding Ctrl actually uses the current snapping mode (at least with transform operators), which was set to Face until I set it back to Increment (the default).

You can enable and use the Drop to Ground addon, it's under the Testing category. After, that just select the object then the ground plane and press Drop to Ground. No need to change your object centers or any cumbersome tricks with the 3d cursor.


text:
Slide the legs of a table
Here is very simple model of a "table":

How could I easily slide the selected part closer to the inside, i.e. move it along the X axis? If I just move it, the top part will obviously be distorted:

Instead, I would like the top part to protrude like this:

How would you do this?

I would move this leg including the top of the table, and later extrude the side face of the top of the table

That's a possibility. But if I want to keep the top part exactly the same size, I would have to resort to using guides and snapping again. Is there no easier way? I think, if I could somehow "convert" the left most edge (between the top and the leg) to a face of zero area, I could move the leg without distorting the rest. I can't find a command like this though.

I'd suggest to use the vertex rip and then fill as shown in the animation below.

I only ripped two of the legs' verts, not all top four, otherwise this would have been true :)     ( which is why you only need to recreate one face to have a watertight mesh again)

Cool. Probably there is no simpler solution for this particular case. How did you select the edges around the hole without using the mouse (or did I just not see it?)

Alt + right mouse button on the edges (the gif recorder misbehaved, so the mouse cursor is offset from where it actually was)

Press P key with the table leg selected and choose Selection,

to separate it by selection and then Shift select the table and press CtrlJ to join them back together, now you can move it however you like.
-don't forget to exit the edit mode of the table before you join them

Select the side face of the table top

Shift S and 'Cursor to selected'

Move the leg including the table top on the X-axis

Make 3d cursor as pivot point for later extruding on the X-axis

Extrude the side face of the table top and scale to 0 on the X-axis


text:
Linking appended objects
Newbie here.
Is it possible to link an object after it has been appended into a scene?
I Appended few objects to a new file, but now I think it would have been better to use link so to have the changes (i.e. adding materials) in each object (file) reflect in the scene containing them all.
I read this Coverting an appended object into a linked object?, but didn't understand it.

Hello :). Of course it is possible. Go to File > Link and link the object instead of appending. You cannot directly change the appended object into a linked one.

Yes. You need to select all the objects you want to link in Object mode, selecting the 'target' object last. Where the target object is the object for which you want to link the material from. Then press Ctrl + L and this will bring up the linking menu. You then can select Materials and all object will link to the targets Material.


text:
Fluid starting point
I want to run a fluid simulation, but I want the fluid to start at some other frame than the start.
How do I make the simulation start on a farther frame?

You could do this by adjusting the offset value of the fluid simulation.
Here's a short summary of this:
Go to the offset settings of the Blender fluid domain (Assuming you are using Blender v2.81 or before), and adjust the value to a higher number to make the simulation happen earlier, and lower to happen later.
This will cause your fluid to show up later or earlier depending on the offset value. For a detailed answer to a similar question, look here.

AWESOME THANKS!


text:
Can't select bone in pose mode and object together
I want to select a bone and an object and then go to weight paint mode, but Blender won't let me select the object when I'm in pose mode, the lock object mode in edit menu is unchecked. Why will it still not let me select one bone and the object together?

You don't need to have them selected together to enable weight painting for that particular bone. To have the settings for weight-painting a certain bone's affect on an object, you must select that bone in pose mode, and then just select the object the bone is controlling. There is no need to select them at the same time, as this can not be done in pose mode.

I can not select object in pose mode ! I already said that! and the lock object mode is off!

A picture would help


text:
How to avoid permutations of vector objects when dumping data?
I'm trying to write a script which recursively dumps all data found in bpy.data.
The idea is when a .blend file is messed up I could compare it with an earlier version and could find the exact changes.
Running the script below the default scene already creates a 160 MB file this is caused by lines like:
bpy.data.brushes.clone_offset.xx.xx.x=0.0
bpy.data.brushes.clone_offset.xx.xxx.x=0.0
bpy.data.brushes.clone_offset.xx.xxxx.x=0.0
bpy.data.brushes.clone_offset.xx.xxxy.x=0.0

I don't understand where they do come from, how should I cope with vector objects?
The full script:
blender.exe --background -P dump.py

.
import bpy

map={}

def dump(obj, name="", level=0):
    if level > 5:
        return
    print("call %d obj=%s type=%s" % (level, str(obj), str(type(obj))))
    if str(type(obj)) in ("<class 'builtin_function_or_method'>",):#"<class 'Vector'>"):
        return
    if id(obj) in map:
        print("already dumped=%s" % obj )
        return
    map[id(obj)]=obj

    if str(type(obj)) == "<class 'bpy_prop_collection'>":
        print("isbpy_prop")
        for item in obj:
            dump( item, name , level+1)
            return

    if str(type(obj)) == "<class 'tuple'>":
        idx=0
        for item in obj:
            dump( item, name + "[" +str(idx) + "]", level+1)
            idx = idx+1
            return;
    for attr in dir(obj):
       if not hasattr(obj, attr ) or attr.startswith("__") or attr in ("bl_rna","base","rna_type"):
           continue
       val = getattr(obj, attr)
       if isinstance(val, (int, float, str, bool)):
          print("%s.%s=%s" % (name,attr,val))
       else:
          dump( val, name + "." + attr, level+1)

print(60*"-")
dump(bpy.data,"bpy.data")

The swizzle properties Vector.xyz return a new instance of Vector.
I.e. using a python property
class MyVectorClass(tuple):
    def get_xxx(self):
        return MyVectorClass((self[0],)*3)
    xxx = property(fget=get_xxx)

v = MyVectorClass((1.0, 2.0))
v.xxx.xxx.xxx
#equivalent to
v.get_xxx().get_xxx().get_xxx()

I would suggest Vector.to_tuple. That is everything you need.
BTW: To properly check for the type you should use isinstance
import mathutils

if isinstance(v, mathutils.Vector):
    t = v.to_tuple()


text:
Where is the animation play button in 2.7?
I was used to press the play button for a preview of a rendered animation
,
all of a sudden (v2.7) there is an audio button  which opens a file dialog. Am I supposed to add all images into the VSE every time?

You can instead use the option in Info > Render > Play rendered animation, or press CtrlF11


text:
How to solidify photogrammetry model by filling it from inside?
I struggle with making a photogrammetry model a solid.
I tried a Solidify modifier, which works quite well until the thickness value is big enough to intersect trough the outer shell and destroy the fine structure. And unfotunately the safe value (for not intersecting the outer shell) is not enough for a desired thickness of my solid to be 3D printed.
Then I just made a solid by intersecting the model with a cube, triangulating the new solid and trying to scrape out the material using sculpt. OK, still I cannot control the distance between the model shell and my digging. This results in occasionaly intersecting the outer shell. And I want to optimize its volume to keep the printing cost lower.
So, is there any way to fill the mesh (viewed from bottom on the attached picture) like "pouring some clay" inside to stick to the faces in a given distance? Any parameters to Sculpt tools that would not affect the outer original shell?
Please, help me to solve this issue as it seems to be out of my Blender experience.

EDIT: After 10 Replies answer I need to add a visualization of the final result of the recommended transformations. The lighter shaded faces are those of a "shrinked" extruded inner shell.

Try going into edit mode after selecting the model. Press E and then Z to extend only in the z direction. Now, if you want the bottom to be completely flat, press S, and then Z to only scale in the z direction, and then type 0 on your keyboard.

Thank you 10 Replies, seems to be logical and works as a "shrink" tool. But in case of this complex form eg. window openings got filled / covered with some parts of upper walls scaled down. I will try to add a picture of it. So, the method would be perfect for a less complicated shape.

Based on 10 Replies's insights and some previous trials I found a method like this:

Modifier Solidify, thickness 1 (m), clamp 1.0, offset -1.0
Switch to Sculpt Mode > SculptDraw
Some smoothing added (0.335), Sculpt Plane to "View Plane", "front faces" ticked (!) and "Add" mode on.
From the bottom of the solidified clamped object I use the SculptDraw to add some thickness to the bottom/inside shell. Works like this thermoinsulating foam to insulate rooftops :)

Must be enough so far. Anyway, as a complete rookie in Blender and Python I would direct my inquiry to all of You how are developing some new add-ons. Previously I tried "digging out" some material from intersected solid by sculpting. It was really fine method, but in the end I always cut out the outside shell and spoiled the original structure of the model.
Is it possible to add any constraint to sculpt out / subtract until the defined distance from the bottom of the face of external mesh is reached? It would be a great limitation preventing from intersecting of the outer and inner shells.


text:
Bone Heat Weighting Error
So I have tried multiple solutions around this page and nothing so far has worked. I am at the end of a blocked off tunnel with nowhere to go. I beseech help.
https://www.dropbox.com/s/8kg70lk9asmg39n/The%20Fallen.zip?dl=0
I am using Riggify and Automatic Weighting.
I have tried to remove double vertices and get rid of overlapping faces with no luck. The bones for the armature are positioned correctly to the best of my knowledge and I made sure to reset their axes so the movement would be correct.
The only thing that I havn't tried is doing it manually, mainly due to how complex it seems.
I simply want to get it rigged for animation. I just need simple movement of the body and limbs.

Please edit your question and provide textual information about the problem you are experiencing and what you want to achieve. Also state what you have tried and how it failed. Don't rely on a downloadable file for people to guess what you want.

You should definitely go toward manual weighting, which is not as complicated as it seems: automatic weighting is a fast shortcut for simple models that don't require fine tuned movements: it's not wortking on your model because it needs a manifold, joined, closed unique mesh, while your model is broken into multiple pieces and is far too complex to be manageable by automatic weighting. When you parent the mesh to the armature choose the option "With empty groups": this will create an empty vertex group associated with every bone marked as "deforming" in the armature, then select the relevant vertices and assign weight. Here are some useful weighting tricks: Rigify : skin overlapping clothes

Thank you. Took me a while to figure out and do but I achieved a "good enough" point.