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My animations blend with each other when exporting in .glb/.gltf
My Blender is v. 2.93.4. The following issue exists in both .glb and .gltf exports.
I got an animated test model made of 3 boxes. It has one bone for each box.

It has 4 action track animations moving the left and right boxes. They are recorded in stash form, and are named A, B, C, D.

All animations are rotating types.
A waves the left and right boxes back and forth.
B waves the left box sideways.
C and D both wave the right box sideways.
On Blender the animations work as supposed to. Below is the B track in Pose/Object mode:

However, if I export them in .glb/.gltf form with these settings:

The box which isn't supposed move repositions in tracks B, C and D. Below is the B track after export:

This doesn't affect the animations in Blender, all I have to do is reposition them back properly. However, once I import the .glb/.gltf file into Godot (v 3.2.2), the box that isn't supposed to move repositions itself in tracks B, C and D. Below is the B track in Godot:

It doesn't move, it just repositions itself.
At first I created only A and B animations, and both exporting and importing went without trouble. But after I quit, restarted and created C and D, these issues started, and that's when B track got corrupted as well.
Since the repositioning happens already in Blender, I assume the problem is in the exporting phase. A, which moves both left and right bones, works fine, and the middle boxes bone, which doesn't have any animation to assigned in it in any track, doesn't move when exported or imported to Godot. That's why I assume that export for whatever reason repositions the idle bones that move in other tracks.
Is it possible to fix this? I've looked up similar problems before and they've suggested combining the animations into one. But I'd like to know if it's possible to keep the animations in a separate tracks, and if not, why?

Try with a Blender 3.0 beta, a recent change may have affected this.

The problem appears to have been some kind of version bug. The model exported from 3.0.0 Alpha works as intended for now.
UPDATE: The same problem started with 3.0.0. I assume this is a bug.


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Animations combine by themselves
My animations keep combining with each other for some reason! This problem has persisted with several models and with many versions of Blender. I've made a simple animated model to demonstrate this issue:

The model in base form viewed from front. No animations activated
I've made six animations, three for both bones. Each animation is supposed to move the single bone around some axis.

Oikea means right, vasen means left
I've saved the animations with push down. However, when I exit and start the Blender again:

The Right_X animation merged with Left_Z. Note that action editor only shows the right bone's keyframe, even tough the left bone moves as well.
All animations have merged with an animation that moves the other bone. All right bone animations also do the Left_Z and left bone ones the Right_Z. Can anyone explain why this kind of thing keeps happening and if there's any fix for it?

If you push down an action, it will appear in the NLA as a strip and this strip will be played, unless, in the Dope Sheet, in your new action, you've keyframed the same bones, in that case these Dope Sheet keyframes will be prioritized.
So you either need to click on Stash instead of Push Down (and the strip will be muted), or in the NLA mute the strip you've already pushed down, or, if you have no particular reason to put your actions in the NLA, simply click on the Fake User button (shield icon), to make sure that your action will still be available when you'll reopen the file:

You can play all the actions you want, they are still available in the Dope Sheet if you switch it to Action Editor mode. But if you have strip playing in the NLA you first need to mute them, otherwise they may also play with the selected action (or simply remove the tracks or the strips of the NLA):

Okay I managed to mute the NLA track. But now I have to put it back on whenever I want to play the track at all. Why the heck is this built so inconveniently? Why can't I just play one animation at a time?

i'm not sure what you mean, you can play one action at a time, either play it in the nla or play it in the Dope Sheet, but do you have a reason to use the nla? or all these actions or tracks in the nla? if not, remove the strips or tracks

Do you call Action Editor NLA? In it I have to mute every track for bones that I don't want to move in the current animation, and that is awfully inconvenient. If there's any option to play just the current animation with all other bones staying still, I'm all ears. Also Dope Sheet doesn't have the animation list.

the NLA is the Nonlinear Animation editor, if you press the Push Down button it creates an action strip in the NLA and this action is playing over the action that you'll load in the Dope Sheet, so I'm not sure why you Push Down if you don't want the action to play

Well I've pushed down since some of the animations wouldn't be saved otherwise.

of course they are saved if you press Stach instead (which pushes the action in the NLA but keep it muted) or simply click on the Fake User button as I show in my answer

Okay, are you saying that I can't play a single animations that I've pushed down anymore, unless I mute each unused bone's track. I should've used stash or fake user in the first place, and there's no fixing it?

you can play all the actions you want, they are still available in the Dope Sheet if you switch it to Action Editor mode. But if you have strip playing in the NLA you first need to mute them, otherwise they may also play with the selected action

please see my edit, maybe you haven't understood yet how Dope Sheet and NLA are working

Okay, finally discovered the nonlinear animation editor based on the picture. Thanks for your patience!

source: Stack Exchange

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

sort: votes


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how to use matplotlib interactively with blender?
I use Blender to explore and render some data that I have in real time.
Besides that, I also have an interactive matplotlib application that further helps me explore and report on the data.
How can I integrate my matplotlib into Blender, so I can use both of them in real time?

This answer reports the best solution I found so far, I'll be happy to hear from feedback or better alternatives:

I wanted to integrate matplotlib into Blender in its own space, but sadly learned that the Blender 2.80 API can't (yet) create new space types.
Therefore the solution for me was to let Blender's Python3.7 interpreter run a separate matplotlib window in a child process (see image).

For that, I had to do the following things:

Make sure import tkinter works (here how I did it, no root privileges needed). With that, it should be possible to <BLENDERS_PYTHON> -m pip install matplotlib and import it. Note that running matplotlib in plt.ioff() mode blocked Blender, and running it in .ion() mode did nothing. Running it on a child process solved it for me.
Make sure multiprocessing.Queue() can be instantiated (In my Ubuntu17 system, this required to copy the _multiprocessing.so file from my non-Blender lib-dynload Python environment.

Now running the following from the Blender interpreter should spawn a child process, that interactively reacts to any changes that the Blender user makes to queue:
import matplotlib.pyplot as plt
import multiprocessing as mp
import numpy

def worker(q):
    fig=plt.figure()
    ax=fig.add_subplot(111)
    ln, = ax.plot([], [])
    fig.canvas.draw()   # draw and show it
    plt.show(block=False)
    i = 0
    while True:
        obj = q.get()
        n = obj + 0
        print("sub : got:", n)
        lnx, lny = ln.get_xdata(), ln.get_ydata()
        ln.set_xdata(numpy.append(lnx, i))
        ln.set_ydata(numpy.append(lny, n))
        ax.relim()
        ax.autoscale_view(True,True,True)
        fig.canvas.draw()
        i += 1

queue = mp.Queue()
p = mp.Process(target=worker, args=(queue,))
p.start()

Once the window is open and listening, add entries to the plot, for example like this:
queue.put(bpy.context.scene.frame_current)

The new entry will be interactively incorporated to the plot. Once you are done, simply kill the process with:
p.terminate()

Hope this helps!
Cheers,
Andres

Missed this, and have done it somewhat differently.  Can specify a backend other than tkinter .This gives a list   matplotlib.rcsetup.interactive_bk to test against those available.  On linux I use GTk3Agg

Thanks for your feedback, as always very valuable and appreciated

I use matplotlib with blender, in both distributed addons and in stand-alone scripting solutions. Let me give an updated answer that me and the users of my addon have converged on is the overall best solution. Will outline why we feel that way at the end.
In short:

install Tornado webserver, and
change the default backend to webAgg

here are the steps to do this for a complete beginner (Blender 3.6.x). This assumes that you want to use the bundled Blender python interpreter. If you preferr your own blender interpreter, that is possible too, but requires some more steps involving deleting the folder of the bundled interpreter (at which point Blender reverts to the system version)

Find the location of the bundled interpreter. From inside the Blender scripting tab, find the console and run:
import sys
print(sys.exec_prefix)

setup the environment. open a terminal (for windows and mac the procedure is nearly identical):
cd <interpreter_folder>
bin/python3.10 -m ensurepip
bin/python3.10 -m pip install --upgrade pip
bin/python3.10 -m pip install tornado
bin/python3.10 -m pip install matplotlib

set "WebAgg" as the default interpreter:
sed -i 's/#backend: Agg/backend: WebAgg/g' lib/python3.10/site-packages/matplotlib/mpl-data/matplotlibrc
NOTE: above is a SED command in Linux. It modifies the file "matplotlibrc". In Windows, you can find the file manually, and modify it. Instructions are in the file, look for the line with "## * BACKENDS", that explains how to do it.

After you have done these steps, every regular python snippet you have that runs pyplot should run flawlessly inside the scripting tab in Blender. Although, it will run through the webbrowser. You will still have the same interactive power with your plots as you do in other environments (zoom, save figure, get coordinates etc)
Why is this the superior solution?
This is verified to work on every OS, and there is every indication that it will continue to do so in the future. This circumvents the need for a secondary process/thread, by letting it be routed through Tornado, via webAgg backend. This is important, because even if you do get a solution up and running on some OS, with some particular backend... you can expect there to be instabilities, if not in todays version of Blender then tomorrows. I have seen this happen, and lost a lot of time banging my head trying to find whats wrong.
Finally, this is the only solution that allows you to directly use the same code snippets from your other work into blender without some kind of modification. If you are working with alot of code that you want to run, then even trivial porting efforts to special solutions are to be avoided.

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


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Eevee: Vertical line running through reflective/shiny hair particles
I have an issue with Eevee when trying to view and render hair particles. I want to use shiny hair, but whenever the hair material I'm using is reflective or metallic, a vertical line appears in the camera view, user perspective view, and render view. When I move to orthographic view, it disappears. If I move the object around, the vertical line is still visible but remains in the same place (at the world origin point). No matter what I change in the hair particle or hair material settings, I can't get this vertical line to go away. There's nothing in the scene or the HDRI that would be causing such a reflection (it appears regardless of what else is in the scene). Does anyone know what might be causing it?
Here is the .blend file: https://pasteall.org/media/5/8/585db6c7efdc0f210599cf27189b99b6.blend

[

Hello and welcome. Please don't post the same question more than once. If your previous question was put on hold, address raised the issues by editing it so it can be reopened rather than post a new one, otherwise see What should I do if no one answers my question?

Sorry, the first time I wasn't aware of how to include the .blend file, so I deleted the original question and resubmitted it.

Your blend file is missing the environment map, which is essential to diagnose the issue

Sorry about that. It appears regardless of which environment map is used. Here's the .blend file with everything packed: https://pasteall.org/media/0/9/091c3b434b2c4dd5bec06aae9c7d46d0.blend

The solution is to enable Screen Space Reflections in EEVEE.


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I'm having flickering problems with meshes in blender2.83 especially in edit mode

After I opened blender 2.83, I deleted all objects in the default scene and added a cube. When I tabbed into edit mode, the faces are flickering. I tried to change the clipping distance to no avail. Since the cube is the only object in the scene, the problem can't be with overlapping geometry. What must I do? Notice the top face of the cube.

Maybe you don't have duplicate geometry, but you have duplicate faces. Try selecting a vertex and moving it around. This could be caused by you trying to extrude the cube, but then clicking away. To be honest, it is pretty hard to know.

This only happens when I toggle to edit mode in solid view. When I am in rendered view, no flickering occurs when I turn to edit mode.

@Eric Xue I already selected  all vertices and merged them by distance. That pretty much dissolves any double geometry. Besides, that cube is the only object in the scene and I hadn't performed anything on it yet aside from toggling to edit mode.

This problem is caused by an anti-aliasing bug. You can disable anti-aliasing in "Preferences > Viewport > Quality", or wait for the next release.


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Can't move objects, only 3d cursor?
When I use any command in object mode like, G or R, I cannot move the selected object, only this orange dot is moved. Not sure how I got here, but how can I get translation commands back to affecting the objects?

You need to press N on your keyboard and go to Tool. There, make sure that under Options is Transform. You need to uncheck Origins and the two others. That should fix your issue.


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Join meshes after rigifying one of them
I had a model with eyes, gum and teeth and the basic human rigify was giving me errors when automatic weighting. So I separated those parts into another mesh. Now that I rigged one of the meshes, how can I join the two meshes so the entire head moves correctly?

You don't need anything bound to the armature but the body parts which need bone deformations. So eyes and teeth could most likely be parented (or Child Of constrained) to bones, rather than being skinned with automatic weights. In fact, you likely wouldn't want the eyes skinned in any case. Depending on how your rig is built, you will likely want eyes parented to eye control bones so that their orientation can be changed easily.
Note regarding parenting vs. skinning of the eyes: If you want the eyes controlled by bones that exist within your main armature, and don't want to use parenting or constraints to do it, then technically, you CAN bind them to the armature. But if you do this, the eye objects will need vertex groups. The name of the vertex groups must correspond to the name of the bones which will control them. The eyes technically don't even have to be separate objects from one another. They can be two joined spheres, provided they have unique vertex groups, with only the vertices for each eye assigned independently to each of those vertex groups. The eye bones will find the spheres if their vertex group names are the same as those bones, and control them. The important thing is to have only one vertex group assigned to ALL of the vertices for each eye (meaning no other vertex groups exist for the eyes, and so no other bones will ever influence the eye geometry). Then your eyes will move as if they are directly parented to the eye bones, even though they are technically bound to the armature in the same exact way that any other "skinned" mesh is bound to the armature. But the bind behaves as if it is a direct parenting relationship. Meaning rigid. This behavior results from only having one vertex group involved. If only one vertex group exists on an object, then only one bone can ever influence the vertices for that object.
Note on unjoining objects with modifiers: Whenever you unjoin objects, they keep all prior existing modifiers. These modifiers will now exist for ALL newly separated objects. This includes armature modifiers. Simply make sure that you only have the modifiers you need for all your objects as they now exist. Strange things can happen if you have the wrong modifiers in place, and the resulting issues can be hard to track down, since you might not be thinking of this separation step as a possible cause.


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Hide Object or Collection using Keyframe
I have seen tutorials on the older Blender version to hide and unhide an object using keyframes.  I haven't been successful in 2.8.  I thought you could use collections to control this, but no luck.
I basically want to control the visibility of an object and various parts of the timeline.  What's the trick in 2.83.  Thanks

Related https://blender.stackexchange.com/questions/158034/cannot-animate-viewport-render-visibility

If anyone is still looking for a good solution for this, I found this short tutorial that makes hiding and unhiding collections super easy https://www.youtube.com/watch?v=bDF21pjxXAY

Hiding a collection
None of the hide properties of the collection are animatable. That is cannot drive or keyframe them.
Can however use a frame change handler to set.
Here is a trivial example that sets the visibility of all immediate children of the scene collection to un hide when frame is in on list, and hide when frame in off list.
import bpy

on = [1, 44, 66]
off = [10, 55, 77]

def frame_change(self):
    frame = int(self.frame_current)
    for c in self.collection.children:
        if frame in on:
            c.hide_render = c.hide_viewport = False
        elif frame in off:
            c.hide_render = c.hide_viewport = True

#bpy.app.handlers.frame_change_pre.clear()
bpy.app.handlers.frame_change_pre.append(frame_change)

Using a keyframed prop

Alternatively can give the scene a custom property. Make it an integer by giving it a value and default that is an integer.
In the graph editor make the extrapolation constant.
Now we have a keyframable switch to turn on off collection switches.
import bpy

def frame_change(self):
    frame = int(self.frame_current)
    print(frame, self["prop"])
    for c in self.collection.children:
        c.hide_viewport = c.hide_render = self["prop"]

#bpy.app.handlers.frame_change_pre.clear()
bpy.app.handlers.frame_change_pre.append(frame_change)

Uncommenting (removing hash #) from second last line cleans the previous handlers
See also
How can I exclude a collection from rendering with Python?
How to get all collections of the current scene?
disable all collections with python in blender 2.8
Sorting Collections Alphabetically in the Outliner

Many properties in the Properties Panel are animatable, including viewport visibility. Click on the Object Tab (not the Object Data Tab), then look Under the Visibility Section for a property called Show in Viewports and Show in Renders. The small dot to the right of these properties can be clicked to set a keyframe.

but is it possible to keyframe the visibility of a Collection?

I honestly don't know. But the OP asks for a way to hide and unhide objects using keyframes. And this does that.

actually it was in his question, ok thanks I was just wondering  ;)

His question was how to keyframe visibility. In the first paragraph, he happens to mention that one of the things he thought to try in order to get visibility keyframed was to use collections, presumably because they have a visibility toggle. According to him, this possibility didn't pan out. In the second paragraph, he states very clearly what he wants.

I meant it seemed to be in the title, anyway it would make sense to keyframe collection visibility, I don't know why it's not the case

By using an instance of the collection, you can keyframe its visibility/rendering.
I found it in this tutorial:
https://www.youtube.com/watch?v=bDF21pjxXAY
It's a bit tedious to properly position the instanced collection but afterwards it works like a charm.

Keyframe the visibility of an Object
my_obj.hide_viewport = True
my_obj.keyframe_insert(data_path="hide_render", frame=1)
my_obj.hide_render = True
my_obj.keyframe_insert(data_path="hide_viewport", frame=1)

keyframe_insert() Documentation
Possible since Blender 2.80
Collections
Even though you can hide collections with
my_collection.hide_viewport = True
my_collection.hide_render = True

you unfortunately can't keyframe this on collections (yet).

Workaround for Collections
Iterate over every object in a collection and keyframe them:
for obj in my_collection.all_objects:
    obj.hide_viewport = True
    obj.keyframe_insert(data_path="hide_render", frame=1)
    obj.hide_render = True
    obj.keyframe_insert(data_path="hide_viewport", frame=1)

Use a keyframe on scale - set X, Y and Z scale to 1 for object to be visible and scale to 0 for invisible. Probably a good idea to Ctrl + A and apply scale first. This only needs to be done on the parent object and all children will follow the parent. You might have to add an extra keyframe to make the object disappear from one frame to the next, otherwise the object will appear to shrink or grow.


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'Bake data' button not visible in fluid options
(new to blender) i am trying to create a fluid sim in blender 2.83 but in my physics tab under domain there is no 'bake data' button in the options. It's there in all the tutorials i've watched but i dont seem to have it.

It's because the cache type is set by default to "Replay". Replay does not provide any caching at all; it's used for instant replay. If you want to bake data, you should change cache type to modular or final (for final baking all physics)

And don't forget, that you need to save file before any cache type of simulations.

Hi. Thanks for the answer. Just to help people understand screenshots better, I would suggest applying the default theme temporarily while taking them. Thanks.

By default the Cache-Type is set to Replay and interactively shows the simulations in realtime.(depending on your system that is)

marked red the defaults for the "Cache"-sub-Panel and the Type: Replay

There are actually 2 ways for baking:

Changing the Cache-Type to Modular, makes a Bake Data button appear at the bottom of the Settings-Panel. That button bakes and caches the Liquid (if checked) and let's you afterwards bake the Mesh (with it's own button) as well if you so desire (even if Mesh is checked it won't be baked in one go).

red marked, setting the type to "Modal"(1.) displays the Button (2.) for backing
The Cache-Type set to Final on the other hand makes a Bake All button appear in the Cache-Panel and by pressing that one button, the Liquid and if also checked Mesh will be baked/cached in one fell swoop. You can also Free All (If data is cached the button changes) with that same button if needed.

red marked, setting the type to "Final"(1.) displays the "Bake All" (2.) button

Testing/building with "Replay" is the usual approach, thus it is default.
I tend to bake the Liquid and Mesh separately aka. "Modular", but once you are set and do not need to make more adjustments, you can use "Final" to safe yourself some clicking and scrolling.
Happy Blending


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Help me Understand What is Happening with my Transparency?
I need help understanding what is happening with my transparency of the object in these photos, below

Following this tutorial (https://www.youtube.com/watch?v=z2cFVVotcs8), I'm trying to make a wood table with a glass piece in the center. However, when I look through the transparency, I can not see the object through it's own transparency. Is this just how the system works, and I need to make the transparent part a separate object? If i'm misunderstanding please let me know, I'm still new, especially to the node system and transparency system. Thanks!

Can you attach the blend file to your question to clarify some moments, please.
I can tell you in advance that it is better to have transparent objects as separate.

Hi :). There's no need to mix any shaders. For transparency use Principled BSDF Alpha slider. For a glass surface, use the Transmission slider :).

Glass is actually a transmissive material, this is a bit misunderstandable...  what you are doing by mixing in a Transparency BSDF (and the same goes for using the Alpha input on the Principled BSDF as @JachymMichal suggested) is making those parts invisible for the camera. While a Glass BSDF or the Transmission setting in a Principled BSDF also take the IOR into account and still have a reflective surface, the Transparency or Alpha simply make the material more or less visible depending on the greyscale value.

@YuriTitko sure thing! terribly sorry for the late reply, but this is the file with the table isolated https://file.io/OwRxpsjSJwSL
I'm working on trying to understand the other comments and try their suggestions as well, but until I get a better grasp on nodes atleast, I'll probably go ahead with making the transparent parts a separate object then

@Rez There is no texture in it) When you saving blend file you need to tick the box File > External Data > Automatically Pack into .blend. This will let you share the blend with texture.

oh dang, ok tho. "automcatically pack into .blend" is now checked, and the file is bigger! round 2!
https://www.file.io/YK9u/download/FXsQeSGkWXKi
Also it wont let me edit the comment, but thankyou for the replies!


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How to bring back the bottom left panel in Ivy Generator?
The Update Ivy panel on the bottom left is vanishing when I switch to another object. Any option to bring it back?

I know this is an old question, but I'm gonna resurrect it.
Yes. What you're looking for is "Adjust Last Operation...", which can be found in the Edit menu.
The windows shortcut for it is F9. This will bring back the parameter adjustment for the last operation you did.
Bear in mind this is just getting the LAST operation, so if you've done a couple of other things since, then the Ivy is not going to be the last operation and so it won't work.


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Select positions of points in Geometry Nodes
I am trying to attach some instances (of a sphere) on some specific points of a disc mesh (say some specific points on the top portion of this disc) using geometry nodes. Is there any way to attach these instances?, Right now these points are chosen randomly via point distribute node.
Thank You

You could use vertex groups…and put this vertex groups in selection of Point instance node

e.g. you want only to distribute on this points: -> create a vertex group for them

and use this node setup:

and you got:

Note: this is a solution for Blender 3.0alpha

Thanks alot @Chris

You are welcome. If my answer helped you, please check the checkmark left to my answer. Thank you.


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How to add noise to a specific part using shader editor
I made this using Voronoi Texture node with Color Ramp connecting it to Color and Bump. I would like to add noise only to the flat areas. Any method?

I guess in the flat areas the color output of the color ramp is black. So what you could do is use a Math node set to Greater Than with Threshold 0 and use this as mix factor for a Mix RGB node. In Color1 plug the Noise Texture, in Color2 the color ramp output you use for the bump. Maybe you have to multiply the Noise Texture with a very small value or use a Map Range node, since otherwise the noise bumps will be as high as the voronoi bumps.

you can use this node tree:

by changing the "greater than" you can choose the right factor.
I just mixed the color of the noise here - you can of course do whatever you want with it.

Thank you Chris

What you could do is use a Math node set to Greater Than with Threshold 0 and use this as mix factor for a Mix RGB node. In Color1 plug the Noise Texture, in Color2 the color ramp output you use for the bump. Maybe you have to multiply the Noise Texture with a very small value or use a Map Range node, since otherwise the noise bumps will be as high as the voronoi bumps. (This might not be too bad with Bump, but for better visual display I used Displacement as well and there it might be problematic.)

Thank You Gordon

@ArunNura If Chris' or my answer helped you, you might consider accepting one of them: What should I do when someone answers my question?


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How to apply Noise texture to specific portion?
I made this parabolic image with math function and displaced it with the Displacement node.  As in the screenshot when I applied noise texture before the parabolic math node its applying throughout the surface and showing distorted edges while displacing. I would like to add noise texture only in that black portion.
Thanks

Connect your Color Ramp output also to Math: Subtract with 1 set as the first value - this way you invert your value, where black is represented by 1, white by 0 and you keep the gradient (smooth transition). Now multiply Parabola Math custom node by that inverted value to, so that black areas are multiplied by 1 (the height doesn't change), white areas are multiplied by 0 (the height becomes 0) and areas in between are multiplied by a fraction (get higher and higher towards the black).

In linear interpolation, the height change is too sudden, so you might want to switch it to Ease:

For a finer control, you might want to use another color ramp to control the displacement transition specifically (this way you don't have to change the color by using Ease mode on color going to the shader), though I wouldn't recommend moving the sliders on the 2nd Color Ramp, I was getting ugly results...


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Apply a texture on a sphere without showing its edges
I am completely new to a 3D software and i was trying to find a solution for this problem for the past few days but nothing is giving me desired effect. Please pardon me if my terminologies are not accurate.
I need to apply a painting on the surface of sphere which have to look seamless.
I have found a few tutorials in you tube (applying earth map, some textures etc) and I tried it but the seam is there whatever UV mapping i have done. So I thought of making a custom texture with a normal mapping tutorial i found in you tube but i am doubtful if it will do any good to me because of the seams that is continuously appearing after my every try. I am attaching one of the few paintings i have to wrap around sphere here.
Also please advise me which render engine is good for texture exports. I am using Blender 2.79 and when i tried to export an OBJ with cycle render the textures were not exported.
Please help me
Thanks in advance
Arun

Is this the actual texture you want to apply to your sphere?
If so, your main problem is that the texture itself is not suitable for seamless texturing, as its pattern is not regular and/or matching on the opposite edges. Google "make image texture seamless" for possible remedies.
Also, this image will (in one way or another) get severely distorted when mapped to a sphere, no matter what projection you use.

Thank you very much. I will try to make a possible pattern out of this. But Could you please give me some information about the render engine I mentioned in the question?

I'm afraid that I have not a lot of experience with exporting textured geometry, which is why I didn't answer initally. Since you asked, I will try but this answer may not be accurate:
As far as I know, material export should be independent of render engine. If you have your material set up with texture and proper UV map, the export should work. However, it may be necessary to have the texture image in the same directory as the output obj.

Thank You very much for the information


text:
How to change the start simulation time for smoke in Blender
I am trying to make a smokey text with smoke simulation. I am using particles systems to emit the smoke. I want my text to appear gradually for the first 30 frames and then the smoke simulation has to start. I adjusted the start(0) and end frames (30th frame) in Emission parameter settings  for particles systems to create a gradually appearing effect. But the issue is simulation is already getting started from first frame, so the text is not readable. Any methods to keep the text steady (unaffected by simulation for first few frames) and then start the simulation?
Thank You

If you're emitting particles from 0 to 30 frames and the smoke will be generated by those particles, of course the smoke rises from the beginning on. If you want smoke from particles beginning at frame 30, then the particles' start frame has to be 30, not the end frame. If this still produces smoke from the beginning, make sure the smoke's Flow Source is set to Particle System, not Mesh.

if i set start frame to 30, the title wont be able to see in the first 30 frames.

Does your text consist of particles or why won't the text be visible in the first 30 frames? If so, I think your question is missing some information to solve the problem.

The text has particle system. But when i change start frame to 30, the particles will only start to emit from 30th frame.

From the comments on the question I guess it's lacking some important information on how you've set up the text and the particles.
Anyway, if you want to keyframe the smoke emission with an Inflow smoke emitter there are different ways depending on the smoke settings, here are some examples.
If your Flow object is set to Flow Source > Mesh, smoke can be controlled by animating the following values:

the Use Flow checkbox
the value for Density
the values for Surface Emission and/or Volume Emission

If your Flow object is set to Flow Source > Particle System, smoke can be controlled by animating these values:

the value for Density
the Frame Start and End of the Particle Emitter

The Use Flow checkbox unfortunately has no effect on the particle smoke (at least not in my Blender version). Since your comment implies you want smoke from particles and cannot use the start/end frame method, the Density value seems to be your only option.

Thanks a lot for the comments


text:
How to make particles emit from an object at regular intervals without disappearing the already emitted particles
I was looking for a solution of this issue regarding animating the number of particles in blender.
I have to emit particles from a pulsating hole at regular intervals. How can i do it? I tried animating the "render" settings in particle to "none" and "object" but the issue is particles that are already emitted are disappearing.I just want to stop the particles coming out of hole at a particle time without disappearing the already emitted particles.
Any solutions?

i updated my answer

Here's a workaround that might help. If you don't want to create a particle system for each "pulse" but a single particle system doesn't allow switching emission "on" and "off", you have to kill particles in those frame ranges that you don't want them.
The lifetime of the particles should be high enough so that they are visible as long as you wish to see them. Let's say you want to emit particles between frames 10-20 and 40-50 for example.

Place a Collision object where the emitter is, set Permmeability = 0 and enable Kill Particles.
Go to frame 9, set keyframes for Permeability and Kill Particles.
Go to frame 10, set Permeability = 1 and disable Kill Particles and keyframe those values again.
Go to frame 20, set keyframes again without changing the values.
On frame 21, set Permeability = 0 and enable Kill Particles, keyframe them again.
Select all keyframes in the Timeline, Ctrl+C to copy them, then go to frame 39 and paste them with Ctrl+V
Keep pasting those keyframes wherever you want to emit particles on the Timeline.

Timeline example for Collision object:

Now here comes the problem: depending on what kind of scene you have and how and where you want the particles to emit, killing the particles normally takes (at least) one frame, so they exist for one frame and will be visible. If your scene setup allows it, you could disguise this by having the emitter hidden by another object so that those killed particles stay inside there.
If you are rendering with Cycles you can use the Age output of the Particle Info in the Shader Editor for the particle material. Plug Age into a Greater Than node to check if Age > 1. This information can be used as a Mix Factor between a Transparent Shader and the normal particle material, this makes the particles appear at an age of > 1. This is probably the best, because you can hide the Collision object and don't need another object hiding the killed particles.

Cool idea with collision‼‼

The 'Lifetime' of particles can be 'keyframed' and any particles that are generated take on the lifetime at the time it is created. This means that you can control how long each frame's particles will exist for before dying. By pulsing the lifetime between 500 and 1 you can get the following result :

The only issue here is that the Lifetime cannot be reduced below zero - so the particles will always exist for at least one frame. If the emitter is visible then you will see each particle created during the 'off' pulse briefly appearing before disappearing on the next frame.
The solution to these transient particles is to simply hide them by placing a mesh to cover the emitter such that the particles can pass through unaffected :

EDIT: As pointed out by @GordonBrinkmann, while this does work in the viewport, it fails to render as the particles are incorrectly handled as if they expired at the point the Lifetime keyframes back down to '1'. This is the case even if the particle system is first Baked. This would appear to be a bug in Blender.
However, on investigating further, while Blender 2.93 Alpha compiled on 23/3/2021 does exhibit the problem, the latest daily build of Blender 3.00 Alpha as of 4/5/2021 does appear to work correctly. This would seem to indicate the the bug with the handling of keyframed Lifetime appears to have been very recently fixed.
You still do have the problem of the particles existing for 1 frame (the same problem as experienced by Gordon) but that can be hidden behind an additional mesh as described above.

EDIT2: There are some discrepancies between how this operates in Eevee and Cycles and also depending on the start 'lifetime' and how it interacts at the end of the simulation. This all points to some buggy behaviour when manipulating the lifetime in this way. IMO this makes this an unreliable solution at present but I'll put together a bug report to the Blender developers - hopefully this can be resolved at some release in the future. For now, go with @GordonBrinkmann's excellent solution as that requires slightly more setup but should be far more reliable.

Wow, didn’t know that!!! Very useful

Yours combined with Gordon’s shader trick would be the easiest solution

WOW, didn't know about keyframing lifetime either. As @Chris said, combine that with my particles material and then there's no need for disguising the short-lived particles. At least for Cycles I suppose this amswer to be the best solution... as long as the emission itself is not animatable.

TBH, I didn’t know about being able to keyframe this until I started researching for the question. That’s what I love about this site - you learn so much just by helping other people solve their problems :-) It’s a shame the lifetime can’t go down to zero as that would be a fantastic way of achieving this. I’m looking forward to the eventual “everything nodes” particle nodes - I think that will be a potential game-changer.

Well, I guess setting a lifetime to zero wouldn't make much sense because it means, a particle wouldn't even be born in the first place (since you can't set fractions of a frame as lifetime) - which would work like we could keyframe the emission directly as we want ;) Looking forward to particle nodes as well.

What a pity, it doesn't work with my material. Although it's fine in the viewport, when rendering the animation something strange happens: whenever the lifetime is set to 1, all older particles disappear / become transparent and reappear when lifetime is set higher again. Looks like Blender says "this particle may be age 20, but since lifetime is only set to 1 it must be dead." Enable rendering Dead in the particle system they actually stay visible. But also the "really" dead particles who were emitted with a lifetime of 1 get older now, so they don't disappear and my material is useless.

Okay, instead of making them transparent I'm just mixing between red (Age = 1) and blue (Age > 1) particles. But the older ones completely disappear when they are older than 1 and lifetime is set to 1. They reappear in blue when the lifetime is set to 250. So they actually "die" because they are too old for a lifetime of 1, but keep moving completely normal and become visible again when higher ages are "allowed". Strange.

That's really weird - you're right. Works in viewport but completely fails when rendered. Even baking the particle system doesn't work (it creates even weirder results with particles appearing and disappearing mid-path as the lifetime changes). That's obviously a bug. I'll raise it on the developer website.

@GordonBrinkmann That does make your solution far superior to mine :-)

@RichSedman Not really...

@GordonBrinkmann I've just re-tested this and the problem occurs at Blender version 2.82 and seems to occur all the way through to Blender 2.93 Alpha built on 24/3/2021 (that's the latest 2.93 I have installed) but appears to have been fixed in the latest 3.00 Alpha - so in the latest version this is a workable solution.

@RichSedman Oh, great to know  Maybe you should add this information to your answer because as it is now it only works in the viewport, not in render if you haven't got 3.0.

@GordonBrinkmann Good idea - I've edited the answer to include details of the bug having been recently fixed.

Let us continue this discussion in chat.

This is a great source of knowledge! Thanks a lot. Because of the render bug i tried using Blender 3.0 But still the same issue is showing for me. When the lifetime is reaching 1, the already emitted particles are disappearing.

The particle system itself does not provide this functionality. But...of course...there might be different "cheap" workarounds.
You can increase the lifetime of particles so that they are not disappearing. e.g. increase it a little bit from 50 to...let's say...100000.

One cheap workaround:
Give the particles a material and make this material transparent for that timesframes on which you want to have the pulsating "off".
One expensive workaround:
Use python.
UPDATE:
new method with particle info:
use this setup:

this kind of works, but it does not look good because you cannot really "see" the space between when particles are emitting from a sphere....
result on a plane:

result on a sphere:

sphere with better camera angle:

for spherical emitters it might make sense to change the color/pulse like this:

The problem with the cheap workaround is, that all particles will be transparent when the pulsating is "off". But I just got an idea... maybe you can build some combination with particle lifetime... for example like: "if frame number is between (specified range where they should be invisible) AND particle lifetime is below (specified lifetime of already spawned particles that should stay visible), then make the material transparent. But as long as all particles stay in view (I guess so, because otherwise disappearing particles wouldn't matter) they would all switch from transparent to visible.

@GordonBrinkmann yep, sounds good

I'm not sure my idea is good... I mean, those particles that appear in "off time" become visible when you switch back to "on time" again, too. Don't think this is desired.

Well - in cycles we could ask for the age of particles and consider this. Then it would work...

I was talking of Cycles, Eevee can't use particle info. But the problem is, if there is a continuous flow of particles that live "forever", than ALL will become visible when you switch off transparency - even those that were generated transparent.

No, not if you ask for particle age in an age range and continously emit particles....

Let us continue this discussion in chat.


text:
How can I bring back cloth simulation to original state?
I am attaching here the screenshots.I can share the blend file if needed.
When the small sphere hits the large transparent sphere the cloth simulation gets activated. But when the small sphere leaves the surface back the large sphere is not coming back to its original state. Is there any way to do that?
Also Is there any method to apply cloth simulation only to the position where the small sphere hits? Because I need to create 4-5 small spheres with random movement inside the large sphere.
Thanks
Arun

You can create shapekeys out of the cloth simulation and animate those to set the deformation back and forth. https://blender.stackexchange.com/questions/63419/is-there-a-way-to-freeze-a-cloth-with-a-shape-key

Read this link: https://odederell3d.blog/2018/08/17/blender-cloth-animation-to-shape-keys/

Yes !!! Thank you very much, It worked. Is there any method for the second issue, To make the cloth simulation work in the portion where the inner sphere hits? I made a vertex group with the vertices above but dont know where to connect it?


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How to avoid stretching of textures whiile extruding the mesh?
I am creating a beat/pumping effect animation but when i extrude the mesh with shape keys, the extruding edges are really sharp and also with stretching texture (Fig 2).Also from front view there are some irregularities (Fig 1). Is there any way to make the extrusion smooth without the irregularities and also to avoid the stretching.?

in edit mode, look at the options (top right of 3d view) and check "correct face attribute"... but this may work or not depending on what you are modifying.

sorry, i couldnt find the option there

it's in 2.9 version

ok, just noticed you are using 2.83. the option I mentioned is available in 2.9.

Ohh. Is there any other way to make it smooth?


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There is a way to export to STL without the visible files keeping the boolean modifiers
Im try to extrude with boolean modifiers. It looks like this with the hidden objects:
I saw several tutorials where there is a button that says "apply" and they can delete the object, they seem to be older versions of blender. The main problem is that when extorting to stl, selecting the objects I want, the "boolean modifers" are not applied and they appear like this:

They hid the apply button on you. Click on the downward pointing arrow next to the camera on the modifier panel. Apply them top to bottom.

You can also hover the mouse over the modifier to get the blue outline round it and then use CTRL-A to apply it..

Thankyou very much it wortks


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How to stack different materials on beer can product label
I am a graphic designer attempting to make 3d product renders of many beer cans. Each of them has a matte finish art layer with portions masked out to the aluminum can below. In addition, the aluminum also has a color over it like gold to simulate a gold finish, but the rest of the can (top and bottom is still silver aluminum).
I was able to map a gold material to the middle part of the can mesh, so I think I have that part figured out. I saved the label as a png with an alpha, so I figured out how to get it working (to see through the label and reveal the metal behind it, but I have other layers of art that need to go over it. I tried "add node" but "add" mixes the materials 50-50 and it gets transparent and light. I tried mix and I can only see one or the other texture or 50-50.
I need to stack labels on top of each other, (like photoshop layers where the one on top covers the bottom)each with their own alpha channels and material finishes. I have another one with gold foil. One layer might be glossy on some parts of the text. That kind of thing. I'm stumped and the client is hot to trot. I am very new to Blender and probably won't understand unless it's step - by - step. Anyway, thank you to anyone that may have pity on me.

https://blender.stackexchange.com/questions/5069/id-like-to-have-portions-of-a-texture-not-glossy https://blender.stackexchange.com/questions/90064/using-an-rgb-map-to-assign-various-shaders-in-a-material/ https://blender.stackexchange.com/questions/46424/add-a-transparent-image-on-top-of-a-material https://blender.stackexchange.com/questions/32997/how-to-place-a-png-texture-with-transparency-over-a-material

Just to be sure, you're asking how to make the golden metal "shine through" the label? like this here?  https://i.sstatic.net/fIFEg.jpg Mask out the Metallic value of the PrincipledBSDF and the Roughness (inverted mask or use a ColorRamp node).

You need to create separate b/w mask for the top layers, then use the Mix RGB node to mix two layers and use mask as factor. Repeat this with all layers.

Hi, thanks for the post. This site is not a regular forum, answers should be substantial and thoroughly explain the solution and required workflow. One liners and short tips rarely make for a good answer. If you can [edit] your post and provide some more details about the procedure and why it works feel free to restore it, otherwise it may be deleted or converted into a comment. Perhaps add a few images illustrating the workflow and final results. See How do I write a good answer?

Thank you. That is a good lead. I will look into it and see what I can figure out <3


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3D cursor not moving
I don't know quite what happened. I was modeling and I suppose accidentally clicked on something, and now the 3D cursor (The thing in the middle with the red ring around it) stays in the middle.
I've seen ways to snap it to objects, but it'll only snap to that object. If i click on another object it won't automatically go on it. I want the 3D cursor to automatically snap to what object I click. I've tried opening new files but it still won't work.
Anybody know how to make it so it automatically snaps to the middle of the selected object?

This looks like a combination feature request and bug report. The 3-D cursor is supposed to move where you click, not move to what you select. At least, that’s the way it is with the original keymap with right click being select.

maybe you set a shortcut to your cursor to selected action ?

You can press Shift+Spacebar, then Spacebar to use the Cursor tool. Now wherever you click, the 3d cursor will snap to. You can also access this tool by pressing T, which will open the toolbar, and then pressing the 3d cursor icon on the left.
If you want to reset the 3d cursor to the origin, you can press Shift+C which is the Frame All keybind. It will reset the 3d cursor and make your view have all of the objects in your scene visible.


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Getting baked animation values using python while preserving editable animation
I'm trying to use python to get world space location and rotation values of an animated camera, including transformations applied trough parents and constraints.
I need the Values as XYZ coordinates and XYZ rotation in degrees.
I can achieve this by manually selecting
object>animation>bake action
with the options "Visual Keying", "Clear Constraints" and "Clear Parents" enabled:

And then accessing the data from the baked camera with python using
import bpy
import sys
import mathutils
from math import degrees

    cameraRotationX = degrees(bpy.data.objects["Camera"].rotation_euler[0])
    cameraRotationY = degrees(bpy.data.objects["Camera"].rotation_euler[1])
    cameraRotationZ = degrees(bpy.data.objects["Camera"].rotation_euler[2])

    cameraLocationX = bpy.data.objects["Camera"].location[0]
    cameraLocationY = bpy.data.objects["Camera"].location[1]
    cameraLocationZ = bpy.data.objects["Camera"].location[2]

    print("Camera rotation X: ","%.7f" %cameraRotationX)
    print("Camera rotation Y: ","%.7f" %cameraRotationY)
    print("Camera rotation Z: ","%.7f" %cameraRotationZ)

    print("Camera Location X: ","%.7f" %cameraLocationX)
    print("Camera Location Y: ","%.7f" %cameraLocationY)
    print("Camera Location Z: ","%.7f" %cameraLocationZ)

This works fine and it gives me the correct Values, including multiple rotations of the camera, for example 720°.
However, I need to go through the process of baking first and I can't change the animation after that, unless I duplicate the object before baking to preserve the editable animation.
Is there a way to get the same values directly in python without going through the baking process first?
I tried
rotation=bpy.data.objects['Camera'].matrix_world.to_euler('XYZ')
location=bpy.data.objects['Camera'].matrix_world.to_translation()

rotationX=degrees(rotation[0])
rotationY=degrees(rotation[1])
rotationZ=degrees(rotation[2])

locationX=location[0]
locationY=location[1]
locationZ=location[2]

But this does not result in the same rotation values.
I am a newbie to python and blender, as well as to matrices and the corresponding calculations.
So maybe I am missing something obvious.
Can somebody please pint me in the right direction?
If there is a way to programmatically bake the animation without losing the original animation, that would help as well.
The reason for this is that I am using the location and rotation values to control a robot arm. I want wo be able to adjust the animation and get the resulting Values without having to go back and forth with baking.
I hope that makes sense.
Any input would be appreciated.
Thanks.

The baking code is actually in Python, so you can copy what it does. The relevant part is this I think.
The way it knows if rotations should be >360° is it remembers the Euler from the previous frame and makes the current Euler "compatible" with it (adds or subtracts multiples of 360° so its close to the previous one I assume). There's a make_compatible function, but you can also pass the previous Euler to to_euler.
So try this to get it at a bunch of different frames:
euler_prev = None
ob = bpy.data.objects['Camera']

for f in range(start_frame, end_frame):
    bpy.context.scene.frame_set(f)
    bpy.context.view_layer.update()
    matrix = ob.matrix_world

    # Location
    loc = matrix.to_translation()

    # Euler Rotation
    if euler_prev is None:
        euler = matrix.to_euler(ob.rotation_mode)
    else:
        euler = matrix.to_euler(ob.rotation_mode, euler_prev)
    euler_prev = euler.copy()

    # Do something with loc and euler...

Awesome, this way it works exactly as needed! Thanks so much for the quick and detailed reply! Make compatible was the part that was missing. I spent hours on this but did not manage to find the right solution. Made my day.


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Vertex Weight Proximity with an empty is not rendering
I subdivided a plane and applied distortion modifier and distorted the mesh permanently. Then with corrective smooth and vertex weight modifier with target an empty i tried to change the mesh. The mesh change is happening in rendered view but when render the animation for output its not happening, just a still image. The animation is still there as in the screenshots.
Any solution?
Thanks

Highest value of the vertex weight proximity is most likely too high compared to the size of the mesh.

I tried by changing it, but not rendering


text:
Is there any method to make the size random to the instanced objects created via Animation nodes?
I made the instances from a collection (of 4 objects) with the help of Animation nodes. I would like to change the sizes of each objects randomly. Now it seems all uniform and if i try to change the scale its all scaling equally. Any method to do this?

Use combination of Random Number and Vector from Value node.

Random scaled objects from a collection:

Thank you for the answer. But its not working for me.I am using a collection for instancing. I used "Collection Info" and "Copy Object Data" nodes to create this instancing with collection.

@ArunNura It should work. Can you show your full node tree?

Please have a look : https://ibb.co/F6vjHH6

@ArunNura It looks like Object Matrix Output node is overriding Object Transforms output node. You probably only need one not both.

@ArunNura Updated my answer

is it possible to create the instancing with any one of the two nodes you mentioned?

@ArunNura Yes look at my second screenshot

Use a Random Vector node if you want non uniform scale. Don't forget to click on the icon on the right of the node seed field to "Vectorize" the node.

Thank you for answering. But its not Not working for me.Could you please have a look on the node tree :https://ibb.co/F6vjHH6


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Animation nodes not working in rendered view
I made a node setup for a project and when I tried to do keyframing in rendered view there is no effect when I change the values., but in Material Preview mode its working. Please help.
Thank you

In the animation Node options "Node Tree" I ticked auto execution options and it worked !


text:
How to fill a path with objects
I would like to fill the spiral path with the duplicates of crystal objects (as in array modifier).How can I get it?
I am using Blender 2.83.
Thank you

Array modifier + curve modifier?

Look at the example of tentacle from Blender Manuel. The included Blend file should show what you need.
https://docs.blender.org/manual/en/latest/modeling/modifiers/generate/array.html

For your information https://blender.meta.stackexchange.com/questions/1/what-questions-should-be-definitely-off-topic/6#6 .

I tried array modifier + Curve modifier. But the number of object duplicates is not enough to fill the entire path.

https://docs.blender.org/manual/en/latest/modeling/modifiers/generate/array.html#options


text:
How to animate the opacity of a texture painting
I painted a red circular spot using texture painting over a UV Sphere with an image texture. Is it possible to animate the opacity of the red spot?

You need to find a way to mix the basic material and your spot image texture, for example use a MixRGB and plug the Alpha of the Image Texture in the factor socket, then find a way to vary the alpha value, here with a Converter > Math (Multiply):

I found an addon named Texture Paint Layers in which there is an option to change and animate the opacity of each layer.

oh ok, anyway I think it just automatically generates some nodes setups, it's always good to know how they work

Thank for your answer and yeah absolutely ! Its great to know the mechanism


text:
Shape Keys are not working when dyntopo is used to change the mesh
I was sculpting a shape which also needed to be animated. So I used dyntopo to stretch out a part of the model but the shape key is not working. I unchecked dyntopo and stretched out the mesh but its working then. So dyntopo feature not works with shapekeys?

Dyntopo generates geometry while brush paints over the mesh. Shapekeys work best with vertices of the original mesh, so no added / removed ones. Why would you use dyntopo for this?

I am new to the sculpting in Blender. I needed to stretch a portion of my mesh and I found the meshes are getting distorted, so I thought of using dyntopo (like dynamesh in Zbrush) for making more geometry.

Yes, but that won't work with shapekeys since their general limitation is "no new geometry to be added when shapekey is present". Find a different way to stretch the mesh or change the workflow, that's all that can be stated given the current details in the question

Thanks a lot for the information


text:
How to animate with random values in Freestyle Lines
I want to animate the Dashed line with random values. How to do it? Any methods?
Thank You

The stroke and gap lengths can be keyframed. If you, for example, set keyframes at the beginning and end of the animation range, at value 1 for them all, then, in the graph editor, you can give their f-curves a Noise modifier:

I think you're still limited to a (spatially) repeating cycle of 3 dash-and-gap pairs, but it might still do?


text:
Why my Blender is incredibly slow
Configuration of my computer is
I9 10th gen 10900k
Nvdia 2080super 8 gb
64gb ram
Blender version: 2.92
I was using blender to sculpt a z brush model of 6 million poly around 4-5 months ago. But when i open the same blender file the software is slow and cant do anything. The frame rate after adding keyframes is 0.2fps. Its the same with any high poly models. Any solution for this?
Thanks Arun

6 million poly is huge. But if it was running all right before, this might be because 2.92 is in alpha stage and does not yet have memory optimization or something. As a PS, 2.92 might be released now, but I’m not aware of it yet since I haven’t checked their site in a bit.

Thanks for the information.I was working in 2.83

Are you sure you need the 6 milion polygons??? cries in i3-3120M 6gb

I am a newbie to this area, slowly learning. Could you please recommend whats the optimal polygon number, it depends on the project though.?


text:
Blender not displaying correct aspect ratio
Using HandBrake, I ripped a chapter from a DVD at 720x480 using "strict" anamorphic setting of HandBrake. When I play the rip in VLC it plays at 720x480 aspect ratio. And when I view the properties of the video file it shows as 720x480. And when I add the "movie" to Blender it shows as 720x480 but blender stretches the image vertically, not keeping the aspect ratio. Blender stretches it so that black bars are NOT at the top and the bottom. I have blender set to 720x480 (1:1). Anybody know what's going on here?

There should be black bars at top and bottom of the video. Blender does not show black bars but instead stretches (distorts) the image, getting rid of the black bars. 1.2:1 just makes the stretch look more distorted. I would need to go below 1 to create black bars at top and bottom.


text:
How do I select the best Keyframe Interval for video encoding?
The Keyframe Interval is set to 18 by default. How do I know if I should change this? I have Perceptually Lossless quality set. Will Blender adjust Keyframe Interval as needed or do I need to figure out what the best setting for my needs are? How do I figure out what is best for me needs?
EDIT: I am referring to the keyframe interval in the video encoding properties panel.

Assuming that you mean the keyframe interval in the video encoding properties panel (highlighted), this governs how often keyframes are written to the video stream. The default, 18, is one keyframe every 18 frames (or two-thirds of a second.)
As the tooltip states, there is a trade-off between file size and seekability. What this means is that when you seek through a file, the video cannot render correctly until the first keyframe -- this is the first frame of video data that is guaranteed to contain all pixels (the in between frames are "delta frames" and contain only partial information about what changed). So with fewer keyframes (with a large keyframe interval), when you skip through the video it will take longer for the video to "catch up" and start playing. However, because the keyframes do contain basically a whole screenshot, these frames take up more storage space. So if you have a small keyframe interval (lots of keyframes) then the resulting video file with be larger.

Thank you, slerfsterdn. It sounds like I can treat Keyframe Intervals just like the "old" GOP setting. YouTube recommends GOP be at half the FPS so I will use this recommendation to guide me in setting Keyframe Intervals. Thank you so much for your answer!


text:
how to move object to same location of another one
I have two of the same objects. Now i moved object 2 lets say...how can i move it back to the same location and size of object 1  ? is there any way to copy this from object one to object 2  ?

https://blender.stackexchange.com/questions/7388/copy-transforms-from-one-object-to-another

There are various ways.
I would use the align tool.
Select object 2, then Shift select object 1. (The last one selected becomes the one whose position in space is used.)
Go to Object/Transform/Align Objects, then at the bottom of the tools column, highlight X, Y and Z by holding shift down while selecting the second and third axis.
If you've been doing things with these objects that could result in their origins being moved, you should first go to the Tools tab of the Tools editor, while in Object Mode, and set Origins to Geometry for both objects.
As for the size, I'm not sure what you mean. If they were the same size originally, but one has been scaled, of course you could just read off the scale of one and type it into the scale values of the other.


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Is it possible to get Material ID passes with Anti-aliasing rather than jagged edges?
I cannot get a clean anti-aliased material id pass which makes selecting in photoshop a nightmare.
Anyone has an answer to this ?

As of 2.8x you can use cryptomatte

Does this answer your question? Accurate IndexOB and IndexMA passes


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Cryptomatte aliased/jagged edges output
Is there a way to get antialiased output on cryptomatte?

The output of cryptomatte should be as accurate as necessary for the masking. You wouldn't actually use the picker output though, that is just a visual aid for picking the objects you would like to mask. This answer explains how cryptomatte works internally.

@RobertGützkow what does that mean exactly.. what any other way can i save it ?

You can save the Cryptomatte in a multi-layer OpenEXR file. The colored output that is shown in the screenshot is from the picker socket of the Cryptomatte node. This is only meant to select which objects you would like to mask, it's not the actual Cryptomatte.

@RobertGützkow I cant get it to export correctly with EXR...any chance you got a tutorial to point me at ? I watched a bunch but still not being able to do it :S

I've just seen you new question. The problem is that Photoshop has no support for Cryptomatte, so you would indeed need the colored picker/ID pass to differentiate between the objects. This wasn't clear in the original question.

@RobertGützkow Is there any way to have all objects in the picked/matte rather than going one by one selecting ( i have tooo many objects...)

Checkout the answer by brockmann to your newer question, apparently there is a free add-on (or whatever it's called in Photoshop) that gives you Cryptomatte support. That means you don't need to resort to a hacky solution.

The colored image as shown in the question is the output from the picker image of the cryptomatte node. This image is used to quickly pick an object or material from the cryptomatte data. It is not the actual matte.
After picking objects and materials the anti aliased mask will be available from the matte output of the cryptomatte node. This is answered in more detail in Cryptomatte - Clean edges


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I got so many .blend files in my C:/tmp folder....is it safe to delete some of them?
I just discovered  C:/tmp folder that blender creates...but i see many .blend files from other scenes i've worked/working on.
is it safe to delete some of these ? they take a lot of space.

Recommend you do this at a system level. For windows (I use linux, so can't test) see https://www.addictivetips.com/windows-tips/automatically-clean-the-temp-folder-windows-10/  and keep files in tmp for only 1 week.

Yes, you can remove it when your blend has been saved and your task is finish.
Blender use the path set in your preference page setting as below.

I point my temp dir to my Ramdisk(B:/) which automatic disappear after shut down computer power. I still can recover autosave from application crushed. And after shutdown as delete them, nothing is changing in my Blender.
But for safety and performance issue, I would recommend to save the Temporary file in non volatile memory or hard disk. And for Render Cache, a place you don't really care and use, since it might take out a lot of place and is regenerable.

Most files in temp folder are either autosaves, temporary backups, clipboard items (when using copy-paste through Ctrl + C > Ctrl + V) or expendable cache files.
Unless you recently lost any work and some file needs recovery, you worked on some unsaved projects, or Blender crashed or unexpectedly closed and you didn't save your work before, non of those files should be important, and can be safely removed without issues.
Blender doesn't normally store important files in unsafe locations, so unless you specifically told it to (either explicitly or by omission) files in temp locations should be unimportant and discardable.
Be sure that all your files are correctly saved in some "projects" folder in a safe spot in your hard drive. If in doubt use your system's safe deletion system (Recycle Bin for Windows) when deleting so that if something goes wrong you can restore it.


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How can you make it automatically invisible to render if its already invisible in viewport?
The objects i make invisible in viewport i want them to automatically be invisible to render. Is there any cool way to have this option ?

I  do not know of a cool way, but you can click the camera icon in the outliner.

That i know, but when you have too many objects, you need to go through all.
Was wondering if there was some option or python script

bpy.data.objects["Cube"].hide_render = True

Select every visible objects by pressing "A" then hit "W" and select "Restrict Render Unselected"

@FFeller this doesnt seem to work on blender 2.8, nothing comes up after pressin W

@rob thats awesome, but only hides the one mesh with the name you put in the brackets... "cube" but not the other ones....

Handlers
Could set in a handler. bpy.app.handlers.depsgraph_update_[pre or post] are the v2.8x equivalent of scene update in versions prior.
Run this script once. Now every time the depsgraph updates ( a lot ) it will match the hide render attribute to the objects hide status.
import bpy

def hide(scene):
    for o in scene.objects:
        o.hide_render = o.hide_get()

    return None

# uncomment to clear all
#bpy.app.handlers.depsgraph_update_post.clear()
bpy.app.handlers.depsgraph_update_post.append(hide)

Great!  !!!!!

This code when run will hide all the selected objects from being rendered
import bpy

selection = bpy.context.selected_objects

for obj in selection:
    bpy.data.objects[obj.name].hide_render = True

It also make sense if you are doing this a lot to change the functionality to toggle.
This version will toggle the render visibility of all the selected objects
import bpy

selection = bpy.context.selected_objects

for obj in selection:
    obj.hide_render = not obj.hide_render

thanks @batFINGER, updated

In 2.79 version we could move the selected objects to some other layer and leave that layer hidden. Could it be a similar way to do it in 2.8? Unfortunately, I can't use the 2.8 version yet.


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Does unpacking textures give better performance in viewport and render?
I've gotten used to automatically packing my textures into the blend file, but I wonder if that can make my viewport perfomance slower, (Rendering and not rendering in viewport)
Should I unpack for better experience or it doesnt make a difference ?

i recommend reading this: https://artisticrender.com/blender-pack-external-files-how-why-when/

AFAIK it doesn't make any difference.

I doubt it will make any difference as in both cases the image is loaded in the RAM

Does this answer your question? Does the file size of the blend file influence the render performance?

Loading packed images from inside a blend file is generally slower than reading the same image file directly saved in the file system, so whenever the image is read it may take longer, but after loading into memory it should make no difference

Judging from my own experience as well as the article linked by Harry McKenzie, no, packing files does not affect render performance. The file still ends up loaded into the RAM in generally the same way. The blend file will be larger, however.


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How to copy the whole blender file into a new one without losing collections?
Sometimes a scene that will have some unsolvable error, the easiest way is to copy everything to a new blend file scene but with that, everything goes into one collection instead of how it was in my previous file that would be very organized. any workaround ?

Maybe export it? and then reimport it, or literally copy paste the information between 2 blender windows?

try appending the file.  file>append

Hi :). You can append the whole scene, or collections into a new file. Simply drag'n'drop your old file over a new blender window > Append.


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After importing svg, [mesh from curve] creates annoying results?
I have created some top views of buildings from AI CC2015 with simple paths, exporting to SVG files.
After importing in Blender 2.73, I want to extrude them to make buildings. I pressed Mesh to Curve & *Tris to Quads. Some of them look just alright, while some of them become weird with overlapping faces.

Is there anyway to clean/fix this? Thanks in advance.

you might want to do a boolean Union on the Paths in Illustrator before exporting as SVG. this will avoid any overlapping geometry and make the conversion cleaner.

Make sure there are no overlapping segments in your curves before conversion, otherwise remove doubles after conversion to mesh.
Before conversion to mesh make sure your curve is set to 2D and the Fill is set to either just Front or Back, not Both
Also have in mind that converting curves to mesh will always lead do triangulation, and not all curve shapes can be filled entirely by quads, nor without NGons.
Also, if your curve had wholes in them, additional edges will appear, because the mesh structure doesn't support islands. That means there can't be totally disconnected groups of edges sharing the same faces, like in tha building with the whole in the middle.
See this answer for more cleanup techniques

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


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My blender has not one option that I really need
Actually I am working on blender 2.79 and I want to rig a car and I completed some steps through video tutorial which I found on youtube.
Now I need one option which is cycles setting in object tab of properties panel, but in my blender there is no option of cycles setting.
What to do for that, should I download any plugin?

At the moment, you're using the Blender renderer, so there are no Cycles settings -(The panel is context-sensitive.) Switch to Cycles in the top bar of your window.

maybe related/duplicate: https://blender.stackexchange.com/questions/15681/how-to-set-render-engine-in-blender

You must change Blender Render to Cycles Render to enable it.
See it at the top menu bar.
Image below:

You're not in Blender Cycles—these are "cycles settings." Change your render engine to Cycles and it should show up.


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Multiple materials on same object creating weird textures overlapping faces. Glitch or user error?
I recently finished a simple model and was practicing adding different materials. I have done this before and never ran into this problem. I created a material (bottle) and applied to the cylindrical shape. I then tried to create and apply the steel.001 texture to the face that is highlighted in the first image. I also applied this on several adjacent faces to better show the effect happening. I additionally tested applying the steel.001 green material to the long face to the right of the highlighted face.
I'm getting a strange result where the material is either overlapping onto other faces or not taking up the full face, which is something I haven't seen before. I'm not sure whether this is a glitch in my program, messed up setting, or a mistake I made, but I've opened and closed the program several times and gotten the same result.

It's probably because you're using a Subdivision Surface modifier. The modifier will move your edges once you'll apply it, but by default you'll continue to see their current position. But the material will be seen as if you applied the modifier:

If you enable the On Cage option of the modifier, you'll see the edges as they will be if you apply the modifier:

yes exactly, thanks!


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Blender 2.82 EEVEE fire simulation appears in preview but doesn't in final render
I've got a really annoying problem. The fire simulation is showing perfectly in the preview, however once I render it, it's nothing there. Everything works in cycles, it's just when I switch to EEVEE. Has anyone ran into anything similar? Thanks.

Bloody hell, I've got it, it was behind the glass in the render lol, and in the viewport the glass was switched off. Eeevee works strangely sometimes...


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Animation mirroring the wrong direction when pasting reverse
I'm new to animating and posting in blender. I have been unable to find any information to solve my problem.
I've got a premade armature. It's already set up and named correctly.
I've posed the right arm and right hand. It's great, I'm happy with it. But I want to make a left handed version.
So I go into the dope sheet.
I grab all the keyframes.
I copy them.
I paste them.
And then the side that isn't posed transfers onto the size that is posed.
Before:

After:

I cannot find any information how to flip the animations and control what direction copies onto what. It seems to be going left to right and I need it to go right to left.
Because I'm new to posing in Blender I might be looking over some obvious setting somewhere.

Try this select hand and go in to Key->Copy Keyframes and then select other hand and go Key->Paste Flipped

https://blender.stackexchange.com/questions/192023/flip-animation-along-an-axis-mirror-animation

Re: Key->Copy Keyframes and then select other hand and go Key->Paste Flipped
No selected F curves.
The link given by John Eason did not work. I already looked at it before posting mine.


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2-D movement in blender?
so I'm pretty new at Blender, and I was curious about how you can make an object (the controlled object) to flip in the other direction without having to face the camera to do so. Like instant flipping everytime i press a direction. If someone could help, that would be cool.

Welcome to the site. Your question is not quite clear, do you want to animate texture appearance ? Maybe related question - http://blender.stackexchange.com/questions/18363/animating-eye-texture-in-a-head-mesh

If you are referring to animation/game engine interaction then all I think you need to do is 'flip' said object very fast, as in a sub-frame timespan

By flipping, do you mean mirroring ?
In that case you can do it whatever the view you have.
Just press Ctrl+M and next X, Y or Z for the mirror axis (in world coordinates)
Press a second time X, Y or Z for the mirror axis to switch to local coordinates.

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


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How can I modify the mirrored side of an object?

I need to modify the mirrored side of the object to add an asymmetrical feature. I haven't found a solution for this yet, any help?
Also, how can I make the mirrored side a part of the object that it is mirroring?
As in, make it modifiable.

Apply the mirror modifier

I can't believe I'm so stupid. Thanks so much!


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Weight colors not affecting strength of bones!
I have made a model and I am now rigging it but when I change the weights of different faces it always acts like it is at 100% strength anyway. This is really annoying!

Weight painting (or assigning) makes comparison between at least two assignement, with an automatic normalization of values:
take two vertices (let we call them A and B) and two bones (boneC and boneD):
if you assign to the boneC vertex group a weight for A 1.0 and for B 0.5, and to the boneD vertex group no weights, then you move the boneC in pose mode, A and B will move exactly with it.
In the same situation let's now assign a weight of 1.0 for both A and B to the boneD vertex group: now move the bone C, 4 BlenderUnits toward left: A will move 2 BU left, while B will move 1.33333 BU only.
Consider that, in case of single wieght assignement, even a value of 0.0001 is infinitely greater than 0.0, so it will be treated in the same way as a 1.0 assignement.

Thanks so much, I didn't really understand what you meant at first but after I played around with it for a bit I figured it out. =D


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Trying to rename an object via keyboard input
Im trying to rename an object when I hit a key so that it overwrites an existing object with that name. I have 5 objects that each have a unique paired (trackTo) object.
if mouseOver.positive:
target = mouseOver.hitObject
if click.positive:
trackObject.worldPosition = mouseOver.hitPosition

the goal is so that when I hit  'TAB' in game, then trackObject.001 (and trackObject.002, .003, ect) all turn into that trackObject as seen above (at different times of course). thus replacing the original trackObject name with w.e else   untill eventually it gets turned back into trackObject, and the cycle repeats.
I dont have much skill in python, but i seem to be getting a basic hang of things, so any help would be appreciated,   also if there is an easier way of doing this, im not opposed to hearing it.

I don't see where you are changing the tracked object's name in your script; only the position of the object that is linked to the controller is affected. This would be easier if we know what you are trying to achieve, this way one can give you a correct answer.

Alright,   ill try to explain  (im not very code savvy here)    There are 5 units. each one needs to have its own trackObject,  Hitting tab would switch which trackObject i am moving when I click.   at any time if I hit space I want the 5 units to activate and goto their respective trackObjects.   i hope i cleared up confusions?  again sorry,  im terrible at code..

Object names
Trying to rename objects is typically a sign, that you do not understand what you really want.
Real world Example:
When you interact with a person you interact with the person not with the person's name.
It is the same with objects, you interact with the object itself.
Search Criteria
According to your description you have a single search criteria: the name.
Where is this name coming from? Obvious when this is your criteria, you need to consider all objects matching that criteria. If you mean a certain object of the set of objects, you need to tell how you differentiate between them. Typically it is one or more other criteria.
Object References
When you already have a reference to the object you want to interact with, there is no need to look at it's name (unless you print it to console for debug reasons).
Analysis
I really do not understand what you are trying to achieve. Rephrasing the question might help. Here are my questions to you:

What objects are tracking?
What is each of that objects tracking?
When pressing Tab what should happen (I do not understand that sentence).
When clicking on an object, what should happen?

Solution
You need to implement a selection operation.

Alright, ill try to explain (im not very code savvy here) There are 5 units. each one needs to have its own trackObject, Hitting tab would switch which trackObject i am moving when I click. at any time if I hit space I want the 5 units to activate and goto their respective trackObjects. i hope i cleared up confusions? again sorry, im terrible at code..

Do I understand you right, you have 5 tracking objects and 5 tracked objects? There is a fixed 1:1 relation between a tracking and a tracked object? Do they all track at the same time (their desired tracked object), or do they start tracking on ? What does "switch" mean? What is the difference between the current (enabled) and the other (disabled) tracking objects? [Just now I think you are looking for a "switching" or "toggling" operation]

Your other question (https://blender.stackexchange.com/questions/69524) gives my the answers I need.

I suggest you ask another question at stack exchange. e.g. "How to switch selection on objects in-game" or so.
You already have a similar question, but it asks for details on a specific solution in your mind, rather than for a solution on an higher level.


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Why is Texture not showing after rendering
Why is texture not show after rendering. It doesn't show in the texture mode (shift +Z)

Unwrap your object

Possible duplicate of Render not showing UV texture

Am using a default texture, not a uv. Musgrave to be precise.  Do I have to always unwrap every time I want to apply texture on an object? Even a plane mesh. Can't I just apply directly to the surface of the obj

Except for procedural textures you most often have to unwrap, unless its a simple geometry, or basic generated texture coordinates suffice, like Object or Generated UVs. If that is a procedural texture then check its scale, it might be either too small or too big.

authors: Николай Дубина


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Multiple addons with the same name found!
How do I fix this problem? I don't even know know which add on is duplicated and how to remove it.

It indicates "(see console for details)"... maybe you should have a look at the console (Window menu, then toggle system console)

Am a newbie.  Don't really know how to go about it not to mention am used to the console part of blender

Just for better readability take your next screenshot using Win+Print. Or some other method you find online


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Where can I download blender screen layout presets?
I want to experiment with different screen layout presets. Preferably set up by professionals, rather than just the default blender preset screens here.
Is there a download source that has a pack of these or some plugin available?

I think this modular plug-n-play feature will be in blender 2.8, called 'Templates':
https://youtu.be/jJJ0_xoD7F4?t=20m22s


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what is the hotkey to change noise distortion types in the displace modifier?
Is there a way to quickly toggle between the different types of noise distortions and Basis' ?
Id like a faster way to switch between them, ideally scrolling through each one for 1s, to see result of modifier. Like a 'next' key for the selection list.

Hold Ctrl + Scrolling over the button will do what you want.


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How can I connect an object with particle instances on an emitter via some Curve/Geometry connection

Hi im trying to get a dynamic electricity effect going on:
Basically, I want an object to pass over a particle emitter, and have lines show up connecting itself to all the moving particle instances on the emitter plane.
No idea how to do this.. seems i'd need to recreate each particle and animate it, then add "connection" curve/meshes for each particle, and then clamp them on both the passing object and each particle. THis seems super tedious if I want 50+ particles.
Any idea how to approach this? I have a hunch 'animation nodes' might help"?
Thanks.

Related https://www.youtube.com/watch?v=k9MvcCXsHHY and https://www.youtube.com/watch?v=quJpVzKK8gc or any other

@DuarteFarrajotaRamos Thanks!, I'll check those out. I'm also condiering just doing a particle system for each particle and having a vortex effect on the object so it 'sucks' the particles coming off each big particle creating a 'connection' looking effect

Create an edges between each alive particle and the object using the Create Edges Node then use the Splines From Edges Node to generate splines from that and output it.


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Prefetch frames works only at opening blend-file?
On opening a 2.91 Blend-file in the video sequencer, I can see that the "prefetch frames" kicks in. A small orange line starts from the playhead and keeps going until the cache buffer is full (I assume). Previewing the video (for that range) runs then very smoothly. However, after that initial prefetch, it seems that the cache is dismissed and/or not renewed and that the prefetch doesn't kick in any more. Previewing the video becomes then very slow.
I have tried to switch the prefetch option on and off, or changing the field "Recycle up to Cost" (default 10) but that doesn't help. I'm not sure what the "strip cache option" (per strip) does in surplus, but it also does not reset the prefetch frames option.
Am I missing something here? Is there any up-to-date information about the VSE caching (aside from https://developer.blender.org/D3934)?

In Preferences - System you can set the cache limit.
Maybe Ctrl+R(Refresh All) will restart cache.
Cache todo: https://developer.blender.org/T80278

Changing the cache limit size or the cache type (use disk cache), Ctrl+R (or Alt+R) does not reinitialize the prefetch cache. The only work-around so far is saving the file and re-open it. At that moment the prefetch kicks in, the little orange stripe at the bottom keeps growing from the play head and (after a while) the preview runs smoothly again. This keeps on working until you change something in the timeline. Then the orange cache bar dims out and the performance drops to a much lower frame rate. Apparently, this is also the case in version 2.83 and 2.90.


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how to create dashed arrow in grease pencil
I try to create a dashed arrow in Grease Pencil. I had limited success with a custom texture (rectangle with two squares, one in a color, the other transparent). My first trial was with Line type square, but that didn't work. However, now I need to add a solid fill arrow point, that preferably should rotate together with the arrow shaft.
Any suggestions?

In Blender 3.0.0 you can use the Dot Dash Modifier on a Grease Pencil object.
It works by toggling the visibility of points/segments along strokes, so you may need to subdivide your strokes to get enough points. Or dissolve some points to reduce the count if your points are too dense.


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What is the difference between Cross Fade and Gamma Cross Fade effect in Video Sequence Editor?
The docs mention only very briefly this difference: "The Gamma Cross transition is similar to the Cross Strip transition, however, the Gamma Cross strip transition uses color correction while transitioning between the two strips, resulting in a smoother transition that is easier on the eyes."
In practice, it is very hard to see any difference. What does it mean "uses color correction"? Does anyone know about a use case in which the difference is very noticeable?

Mix colors from different channels, for example, Red and Green you will see that the result is slightly darker that you may expect:

So the difference between two cross is in how much color shifts

Thanks. Is this then the same as for example adding a brightness/contrast modifier?


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Blender 2.8 VSE scene strip preview does not show image (as plane) from 3D viewport
In scene1 I have a simple image as plane + some extruded text; eg the title. The number of frames is set to 90. When I add a this scene strip in the VSE, I can only preview the text. The image itself is displayed as a white plane. When I add a camera and render a frame of this strip, I can see both the image and the title. Is it possible to preview also the image in the VSE while scrubbing through the strip?

You should open Properties panel (press N), select scene strip, then find in Properties panel Scene Preview/render tab. You can set here Render or LookDev to view the textures
Note, Sequencer must be in Preview or Sequenser/Preview mode

I can't find this Scene Preview/Render tab. Scene > Filter > Annotations > Custom properties. No scene preview/Render or Safe Areas tab. I' m working in the latest version (2.8.51). Is your screenshot from a previous version? Or am I missing something?

Sequencer must be in Preview or Sequenser/Preview mode

Great! Thanks. In the default Video editing workspace, you can set the Properties panel of the top window; where you can see/preview your video. This window is already in Preview mode.


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Is there a python binding for Undo/Redo?
I'm on a mac, and i can press CMD+Z to undo, SHIFT+CMD+Z to redo.
Is there a way to trigger these in the python console?

Yes, absolutely.
bpy.ops.ed.undo()
bpy.ops.ed.redo()

More operators of that kind here: https://docs.blender.org/api/2.79/bpy.ops.ed.html?highlight=undo#bpy.ops.ed.undo_redo

Thanks, when I clicked undo, the console at the top wouldn't output that as an operation. so i figured they didn't exist haha.

That console does not log quite some operators, so it is always a good idea to check the API document. Fortunately, the naming is quite good there.

I'm wondering if you can add a function that is called back before and or after on which to do some further clean up? and how that's done. [maybe it's another question I suppose.]


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Info Pane: How to copy output?
When I perform actions, the Info pane at the top outputs the equivalent python commands.
If i try to select the text to copy, It won't allow the selection.
Is there a way to configure this to work?

Right click the line you want to copy, and it will highlight. Press ctrl-C to copy and then also right click it again to deselect it or otherwise it will copy every line that is highlighted next time you highlight and copy. Paste it into the text editor, etc.

Ah Thanks! I was trying to drag-select on a track pad, guess single click only works here


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What are the use cases for using either Sverchok or Animation Nodes?
I'm having a hard time digesting all the information inside these two software packages. There are so many options in each one , and some seem to provide the same functionality.
Can someone give a high level overview contrasting the two node frameworks?
When should one be used over the other?
Thanks!

"When should one be used over the other?" They are two competing projects, with a considerable amount of overlapping functionality; use whichever suits your taste best. This question is too broad and open ended, not very fitting for our format here, try https://blenderartists.org/ instead

I'm a Sverchok developer, you can read here about our development focus. If none of that relates to your needs you might want to invest time in AN instead.


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how to access a rigify armature selector UI?
I generated a rig using rigify but I can't seem to find a UI to select the armature i want. I know other VFX setups usually have a 'paper doll' like image with buttons for each part of the character available to animate. Does rigify provide this UI?

There is no such feature as far as I know.
Rigify give you a menu that helps hide/unhide parts of your rig. Look in the N-panel (press "n"). In Item you should see Rig Layers.

Indeed Rigify doesn't provide a "picker", but other addons do.
This one is compatible with Rigify (and others): X-Pose Picker 3.0 - Blender Market


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RTX 2080 graphics card is not recognized as Optix compatible on Debian 10
I have the same issue as Timothy Tinsman on Debian 10 up to date: Blender 2.83 / 2.83.5 and 2.90 don't recognize my RTX 2080 graphics card as compatible with Optix.

CUDA, on the other hand, is functional.
The NVidia driver installed is the one offered by Debian in the non-free repository: 418.152.00 stable.
As suggested by Timothy Tinsman and in this post on blenderartists.org, I checked the packages libnvoptix1, libnvidia-rtcore and libnvidia-cbl. They're all installed.
Another leads?
Thanks!

I switched the NVidia drivers to 440.100 (from the backports repository) and Optix now seems to work.

Now it seems to work also for RTX Titan and Quadro 2000 on NVIDIA-SMI 510.85.02    Driver Version: 510.85.02    CUDA Version: 11.6 driver (debian testing, kernel 6.0.0-4-amd64). Single install of libnvoptix1 package solved the same issue in Blender 3.5.0 alpha.


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How to convert a curve-based animation into an exportable keyframe amination for a video game?
I have a conveyor belt animation obtained by moving on an axis a plane to which is applied a list of modifiers.
The rolling animation is due to the "Curve" modifier, the first one in the list :

As it is, it is impossible to export the object and its animation for real time use.
I have already looked at other posts on stackexchange with a similar question, but the answers don't seem relevant in my case.The treadmill is one single object.
Any idea how to export the object and its animation so that it can be used in real time?
Keyframes or ShapeKeys?
Thanks for your help.

How are you animating this?

Hi,
Simply by animating (2 keyframe) the Y-coordinate of the base object to which the Curve modifier is applied.


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Summary still there in animation dope sheet
Probably a real noob question but started doing an animation. Made a mistake deleted the keyframes. But summary still remains. Seems i am unable to clear this. Even factory reset and open a new object and it is still there. Any ideas how to clear this please?

I don't believe it can be cleared. But it's of no consequence. The Summary is simply an expandable section which gives you a general, at-a-glance view of your keyframe data. It really has no purpose until you have keyframes. So maybe it shouldn't appear until you do. But it's always there regardless. In any case, once you have keyframes, they can all be collapsed under the Summary section. It seems to only exist in the Dope Sheet and the Timeline. If you're seeing it in the Dope Sheet, the top row of keyframes comes from the Summary section. It is very useful, because it lets you move every keyframe from a certain time location at once, irrespective of whatever channel any of those keyframes are actually found.


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Unwanted bump on a mesh after Boolean and Subdivision Surface
I did a hole in my mesh in Blender 2.82 with boolean modifier, and I made some changes about topology so that the subdivision surface modifier can work properly. I removed all the doubles, and I checked the normals, they are fine.

But the result isn't what I've expected. We can see a bump, right below the hole (in red on the image).

Does someone have any idea ? I don't have any problem when I do the same thing on a sphere. Thank You !

This is the kind of topology you need. It has ring-based loops of quads going around the hole.

It produces a rim with no bumps when you add your Subdivision Surface modifier.

It works ! Thank you very much for taking the time to help me.