text:
How to randomly pick an object from a collection?
I am working on a modal that paints objects & then drops them using rigid body.
I'd like to include support for collections, where the user can store a group of objects as a collection & then randomly choose one of those objects to paint.
how can I access objects in a collection & duplicate the chosen object?
Thanks

Use this code:
import bpy
from random import random

#select your collection by name (in this case the collection named "Collection")
col = bpy.data.collections["Collection"]

objNum = len(col.objects)

#Generate random number
randomIndex = round(random()*(objNum-1))
#use the random number to call a random object in the collection
obj = col.objects[randomIndex]

#creat a copy of the object and link it to the collection
newObj = obj.copy()
col.objects.link(newObj)

You may also want to .copy() the object's .data.

You can also use random.randint(0,objNum - 1).

Since I am using a hit raycast, can I duplicate all objects & assign locations to equal the hit value?

Thanks! I will try it out right now.

@Animationsvfx you have to give us a lot more details to understand what you need

@rjg I noticed the object didnt duplicate, does copying the .data do that?

@Tareyes I will post the script later, let me try to set it up & put notes so you guys know what each part does.

@Animationsvfx copying the .data means copying the data block of the objects (if you don't copy it, the changes made to the original object will affect the copied object as well, but the actual object duplcation is done by the obj.copy).
And yes, you might have to change something, depending on your project


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Library model with books
I'm trying to make a model of a book shop, much like a library (hence the title), but i'd prefer it if I could avoid having to model thousands of books and texture/color them. In the end I want to export the model to unity3d.
Is there a way I can model the library without having to model each individual book?
I saw another post a little like mine, but it was about textures and I don't know if I can do it in the same way. (Plus I didn't really understand it)
Thank you very much :)

http://lmgtfy.com/?q=blender+addon+bookshelf

Thank you, that actually helped a lot. Didn't know you could get an add-on...

source: Stack Exchange

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

sort: votes


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Previously tracked frames are changing
I've been experimenting with tracking some footage. I've been advancing the video one frame at a time and setting each frame individually to get a really solid track. However it seems that after a while, previous frames that had my marker dead center in the tracker have begun to slide around. Any ideas what I'm doing wrong?

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


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How to create half circular-window hole on the wall without resulting ngon?
how to create half circular-window hole, I think it called arched window? I only know using knife project, but it will make ngon, and I must cut it one by one into tris/quad.
so, do you know another way to window hole for arched window without resulting ngon?

The answer below didn't address the question asked, and the GIFs he uploaded are causing major problems trying to load. The solution to your problem is to subdivide the face several times, then remove the faces where the arch should be. Use the Circle tool in the LoopTools addon to round out the edges of the opening, and adjust them to suit your needs.

In answer to the question:

Select the face that you want to put an arch opening in
Subdivide enough times to suit your needs:

Select the edges that surround the area where your arch opening will be:

Select the Circle tool from the LoopTools addon (available in User Preferences if not already installed). This will move the selected edges into a circular shape:

At this point, you can either delete the bottom half of the original face and rebuild the mesh for the lower part of your door opening, or you can realign the vertices that will form the door opening by copy/pasting the appropriate transform values to line them up on the z axis. To do this, just place the mouse cursor over the appropriate transform value and press Ctrl-C:

Individually select each vertex below the one you just copied the value from, and paste the value into the same transform field by just placing the mouse over it and pressing Ctrl-V. You should end up with something like this:

Now you can delete the faces that form the arched doorway.

Preparation
The best method to create a nice fitting window (glass) is with a copy of the inner loop of your window.
Select the window, tab into Edit Mode, then select the inner loop, hit Shift+D to duplicate the vertices and then P to create a new object from the duplicated vertices.
Tab into Object Mode, select the new mesh and tab into Edit Mode again.

Create Window
Now we are going to create the faces for the window. Start at the top and select either 4 vertices or - if you have a vertex in the center - select 5 vertices. Hit F to create a face, then proceed until everything is filled.

If your topmost face is an ngon, go to edge select, select all horizontal edges and subdivide them once. Then, switch to face select mode, select the upper face, hit X and select "Only Faces".
Switch to vertex select mode, and create two faces out of four vertices. Hit W and select "Remove Doubles", in case there are leftovers.

There you go, a perfectly fitting window for your frame, completely made out of quads.
Creating the Window Cavity
Select your window frame, tab into Edit Mode, select the outer loop that connects to the wall. Hit Shift+D to duplicate it, then hit P - "Selection" to create a new object.

Tab into Object Mode, select your Window and hide it. Then select your House, tab into Edit Mode and delete the face that should have the cavity.
Tab into Object Mode, select the window loop, then Shift-select the house and hit Ctrl+J to join both objects.
Tab into Edit Mode and select the two lowest vertices from the window arc and the vertex in the corner at the same side of the house. Hit F to create a face (triangle). Proceed until you have both sides of the arc covered, then close the rest of the gaps.

When you are done you should have a pattern similar to this:

Now you have quads and triangles without the need of adding loopcuts to the rest of your house.

Thank, but its not the case, I already have 1 complete window(include frame and leaf). I need create hole on the wall with same shape with my window because I will put my window in the wall, my window is thin that's why I need create clean looking hole in the wall,

And this is exactly why you should have written about the "hole in the wall" when you mean the hole in the wall. ;-) It's exactly the same method, only the other way round. I'll update my explanation, as soon as I have time...

Use Mirror modifier to minimize amount of work done; also Alt is useful for selecting boundary loops to be filled. Surrounding opened hole for the window with an edge loop could be better approach because of avoiding shading artifacts.

@MrZak, applying a mirror modifiert for five minutes of work doesn't sound very reasonable. And there is no shading on the wall either. This method is the cleanest and fastest without adding too many loopcuts around the whole building.

I didn't mean to apply Mirror mod rather than only shrtening gifs which are a bit hard to watch. Fastest way - maybe. Cleanest ? A corner vertex with 8 shared edges ? Well, quite sirprising.

@MrZak - I never had any shading problems in any game engine in the last past +10 years when using that method on a flat surface. But yeah, so BlenderSE is all about sharing. If you have a better idea, I'm always willing to learn something new and there's always room for another answer.

Overall surrounding loop was mentioned as a room for imrpovement house geometry - no house is flat and with perfectly square angles. However there shouldn't be answer about that - yours covers flat surfaces.

authors: Андрей Рубан


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why everytime I convert to curve when I change shape from 3D to 2D I got weird result?
why everytime I convert to curve when I change shape from 2D->3D or 3D->2D I got weird result?

become like this: (straight line)

it moved into origin point with weird shape and not change even I change it back into 3D
NOTE: the curve is from edge (extrude vertices), and I convert it into curve.

Does it look like straight line if you rotate the view as well? Because if you make a curve 2D and your view is perpendicular to the plane of the curve, it will look like a line.

yes, I even I rotate the view, I already trying change to 2D shape in ortho-front-top view, but result is the curve changed into straight line..


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How to make permanent custom tab and removing some submenu in tab tools (T)?
I create new tab by using phyton template in blender, but I don't know How to make it permanent. and I want removing some submenu in tab.
I want to remove this, do you know how?

What you are referring to as a submenu is the header of a panel. The template that you created includes a class that inherits from a Panel, the bl_category value in the panel class decides what tab the panel will be shown in.
Tabs only exist if there is a panel to be shown in them. When there are no panels to show the tab is removed. To make a tab permanent you need to have a panel to show in it that is always available, this may be a python script set to auto-run on startup that is saved to your startup.blend or an addon that is set to be enabled on startup, you do that by enabling the addon and then saving user settings.


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How to make cube A size following cube B size? (boolean for window/door)
ie; I have cube001 for boolean, and cube002 for window frame/leaf, so when I resize high/length of cube002(window mesh) the boolean cube (cube001) is changed too, how to do this?

If you freeze the scale, it's not like
else
http://take.ms/CTUFw

or use constrain http://take.ms/kElvW

authors: Влад Киндюшов


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How to change mesh using driver like cgcookie cookieFlexRig?
how I can change mesh into another mesh using driver.
I found in cookieFlexRig it easy to change clothing model, hair, shoes.
How to do this?

The flex rig doesn't change the mesh, every hair mesh is in place at all times, the visibility is changed by using a mask modifier.
For each hair object, add a mask modifier, then add a driver for the invert option and set the driver calculation so that when a certain value is set the invert is the right way for each object.

A driver is a python expression that determines the value of the property being driven. In the case of controlling the mask modifier, the result should be a True or False value that inverts the mask effect. Drivers can be edited in the driver context of the graph editor.
The flexrig uses each number to "view" a different mesh object, the easy way to determine which is active is to test if a custom property is equal to the chosen number for each item. For example choice == 1 will be True when the custom property is set to 1. A custom property can be added to an object in the custom properties panel which is found in the object properties.
The driver panel looks a little different in 2.78 but it isn't hard to find the same settings - you choose single property and select the object that has the controlling property then enter the property name as if it was a dictionary key in python ["good"] into the path property, then you use the driver variable name in the scripted expression choice == 1

thanks, now I can hide and unhide the mesh, but I not understand for the driver part, could you share that blend file?


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why when I turn off cast shadow, the light can through the mesh?
in first image, just simple scene, but in second image when I turn off cast shadow, the light going through to bottom room.
Blender 2.78a - Cycles

You turn of Cast Shadow and the light doesn't cast a shadow . . . what did you expect to happen . . ?

the light is exist in bottom room, I just want to add light in upper room, but when I disable cast shadow, the bottom room get enlightened

@novice rofl, brutal

This is expected behavior. The Cast Shadow option enables or disables shadows for a specific lamp in the scene. When you disable shadows, all faces act as if they have direct light on them.

so in first image the reason the bottom room is dark because the shadow from middle floor? and when I disable the cast shadow the bottom room is get enlightened? thanks, I understand now, thanks for @NᴏᴠɪᴄᴇIɴDɪsɢᴜɪsᴇ too :D
-by the way, my goal in this scene is having light in upper room, and not have any light in bottom, in upper room i use multiple light so object in that room have multiple shadow too, thats why i want to disable shadow in some light.

disabling cast shadows for one lamp will make it not cast shadows on any objects


text:
Blender 3 - How to enter walk mode?
In the old blender I was able to toggle the camera walk mode with SHIFT + F.
In the documentation it shows how it is done from the menu (View ‣ Navigation ‣ Walk Navigation), but I can't figure out the shortcut.
It says Shift + AccentGrave which I think is SHIFT + ´ but it does not work

Go to Preferences > Keymap> Search by Name: walk , and you will see the shortcut

Thx, I just tried it but there is no match.

You can assign shortcuts to every menu item by right clicking it and selecting "Assign Shortcut":

As far as I can tell there is no such shortcut, at least since Blender 2.8
Shift–` ('backtick' or 'accent grave') enables Walk/Fly Navigation for the selected camera.  How the camera behaves in Walk/Fly mode depends on the setting of Preferences → Navigation → Fly & Walk → View Navigation.  It is definitely not a toggle.

Why on earth did they removed it, I used that all the time. Guess I will need to downgrade to 2.8?

@Black They didn't, it just got changed. I recently had to acquaint myself with this new shortcut as well. Seems like this type of changes occurs with every major update.

FYI Shift+` is a valid keyboard shortcut in Blender 4.1 and 4.2.

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


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Make new objects smaller by default
I am working on a smaller milimeter scale in blender. If I add new objects, then they are extremly big. Why are they not scaled to the unit you work with? Is there a way to make them initially smaller?
Currently I always have to resize them to make them fit my scene, because they are bigger than the whole scene.

Did you try that https://blender.stackexchange.com/questions/70318/how-can-i-make-the-default-size-of-new-objects-1-x-1 ? It changes the default units, meaning your object have the same size but 1m becomes 1mm.

A default file (Header > File > Defaults > Save Startup File) saved with these settings should set you up for working in millimetres:
:

I've tried it. If I add a cube then it is still way oversized.

Ok, I understand now thx to GPT. You mean that we need to go to File -> Defaults -> Save Startup File. I had to restart blender and now it works.

Hi, @Black Sorry.. I'll make that clearer. The adjustment works straight away for me.. but all the tools do remember the parameters they were last used with, so if you created a 2m cube before adjusting the settings, then 'Add Cube' wil add a 2000mm cube, until you type in 2mm., on next use

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


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Rigid Body Simulations never work- everything flies in random directions
I am so confused. I try to make a simple rigid body animation.
There is one piece in the middle which rotates and some other parts are connected to it and should move if the rotation is taking place.
However, if I start the animation, then everything just flies in random directions, even though i selected Mesh everywhere.

do you have all the collisions set to "mesh"?

wait nvm, that was a stupid question. lol

@Edgel3D, I thought it would be interesting to simulate the physics, but unfortunately blender is not capable for even such simple calculations. I also ended up animating it, but it would be interesting to see your solution with the constraint? Can you upload the blend file or show how you did it?

@Black I've done a better version of the example clip.  This one does it all automatically.  Have come in to post it as an answer anyway.  Blend file will be included.  Hope it suits...

This one is rigged, not physic'd.  (I've treated it as a lock)
(Blend file below)

The bones are pulled in reverse to guarantee the locking shaft will move in a dead straight line.
To this end an Empty is animated to the left and is a parent for the shaft.  It's also an IK target for the bone that controls the middle linkage.
As it moves it pulls that bone across to effectively rotate the 1st child-bone that parents the disc, forcing it to rotate also.
It's all done back to front but as far as I can make out, it's the only practical way to guarantee the locking shaft won't vary from it's straight path.
As you've come to realise, Blender is an animator/modeller, not an engineering tool and does require some innovation to get around it's physics limitations at times.  It can be a marvelous brain stimulator!


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Blender 2.8 - How to create new view ports / windows?
In blender 2.7 you could easily create new windows and configure your workspace as you wished, by draggin the symbols seen in the screenshot below:

How does it work in blender 2.8? Was this great feature removed??

It's still the same. Click in the corners of the areas.

It still works the way it always did. But for some reason, the "triangle in the corner" icon has been removed. If you hover your mouse cursor over the corner of a window, you will see it change from a pointer to a kind of plus sign. When this change happens, clicking and dragging will create your new window in the expected way.


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Add new light attaches to floor plane
I have the newest Blender and have a scene I created, and which has a plane used as a terrain. When I add a light which enters at the center, the light attaches to the plane so when I move the light the plane moves with it. And yes, the plane is not selected when I add the light. I was not sure what to search for to solve this problem. Thanks

Ok I went back into Blender and played around with the file and found out I had Proportional Editing switched on. Not sure why it would pull on the ground plane but it did. Turning it off solved the problem.

It pulls on the ground plane because that's what proportional editing does - affect everything that's within the size of the proportional falloff radius. When in Edit Mode, this is limited to the mesh you are editing. When in Object Mode (which you were when adding a light, I guess) it affects all objects which origins are within the proportional editing range.


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how to transfer hair as .obj file
I have imported a head from daz3d and used the particle system to create hair.  I went into the modifiers tab and converted the particles into mesh.  Then I hide the head leaving only the hair visible.   Then I select file and export the file under the desired file name.  When I go into daz3d or wings3d and import the file the hair is not there.   The head appears but that is all.   What am I missing?

Troubleshooting issues with other software is outside of the scope of this website.

If you just converted the hair, you then have a string of vertices. Since there are no faces, these will not show up. They are likely there, you just can't see them. Try giving them some thickness. To do this, convert them to curves and extrude them, then convert back to mesh. Or use the screw modifier with a setting of only 1-3 degrees.

Great. Please set the question as Answered then :)


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Cycles volumetrics: artifacts on edges
I'm creating cloud in Blender/Cycles. While following this tutorial I came across artifacts:. The problem is marked on render (the biggest visible artifact) and seems to appear in areas where faces overlaps in particular way, this places are significantly darker. If I would smooth the geometry, they will go away, but the thing is that I want to keep such fluffy shapes. Does someone know how can it be fixed without changing topology?

I think you will get better results using the new Point Density feature. Clouds are not solid meshes in real life, so trying to mimic them using meshes is a hacky workaround at best. I'm not saying it can't be done - just that you will have more headaches if doing it with meshes.

Those are likely caused by intersecting geometry. Try turning down the amount of displacement if you can, or perhaps a remesh modifier. Also see http://blender.stackexchange.com/q/16188/599


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Unable to make holes using boolean modifier
I am pulling teeth trying to get these cylinders to create holes in my movie reel object. Not sure what I'm doing wrong or what settings I should have...can't seem to get to work with any tutorial.
Here's the .blend file:
http://www.pasteall.org/blend/39092

I can't understand what is wrong but I get strange results, using meshes from that file, even importing them in a new empty file. Some  cylinder at least have a negative scale which is bad for booleans, but there 's something more weird, imho. Which version are you using, and do you know which version created them?

@lakerice, it's probably less effort to start these shapes from scratch. The  thing you need to remember is that Boolean Operations (Currently) still need to happen between 'watertight' objects. (Objects with volume)

@zeffii I tried also to check with 3d printing toolbox, jsut 2 shapes (the big disk to be holed, and one cylinder): it shows just overhang faces, but that is not a problem unless really 3d printing.

As you can see I am new to this program lol.  I didn't realize my shapes weren't watertight and connected.  I had the feeling I was making a lot of mistakes trying to piece different objects together manually.

The problem with your file is that you have a lot of disjoint geometry and non volume geometry.
Observing a small section of the model shows a problem: A, B, and C are disjoint. (Not attached to eachother) and they therefor don't form a watertight (Manifold) volume. Also B and C even have Polygon normals  that go in opposite directions. Which you can tell by the color differences in the mesh. Purple vs Grey.

I'm sure if you study the model further, or come back to it when you have more experience with the Boolean Modifier you will see immediately all kinds of things that make it impossible to do what you are trying. I suggest a different approach, it's easier I think.

Here's a demonstration of what my approach would be to this. Use the Screw Modifier and a profile as the rotation shape. A benefit of this is you can easily change the number of vertices on the circumference of the object, by changing the 'Steps' value.

I've also used the Array Modifier to make a radial array, this arrays an object (The extruded Circle) around a fixed point (an Empty). The Empty's rotation influences the rotation of the repeated object.

Then finally you can add the boolean modifier and hide the Circle object.

Thanks so much for your help Zeffii.  It really is appreciated.  I've been looking at these instructions and what you did in the file, trying to figure out how you did this step by step.  I see you started with a circle to make the reel and used the screw modifier, but how did you get it to be solid and 3d?  And how did you get that ridge around the outer region.  Sorry if I'm missing obvious things...I'm new to Blender.

that's OK lakerice, you'll understand these things faster than you think. I'll update the answer. But in the meantime here is the short instructions to get a cylinder.  Add a Circle -> change to Edit Mode -> Select all Vertices -> press F. (this fills the verts, and makes polygon). -> Select the polygon and press E to extrude, moving the mouse will increase the Extrusion.

you can also just add a Cylinder Mesh.

Thanks that helped.  However, now I am trying to do what you did in the centre of the reel, but when I use a second boolean modifier in the plane object to difference of circle.001 it makes the entire reel disappear.  Basically I'm trying to get the same holes duplicated but scaled down to the centre of the reel.  http://www.pasteall.org/blend/39111


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Is there a way to keyframe a modifier to turn on or off?
I'm trying to fracture an object after it hits the ground.  Basically, it's falling and hits the ground, then another object smashes it.  I don't see any way to keyframe the execution of a fracture from the fracture modifier, so I'm wondering if I could simply turn the entire modifier on or off with keyframes.
Thanks

No, I dont think there is as far as I know, but most modifiers have an Influence or Value property that can be keyframed, and when put to zero can effectively "disable" a modifier. Not sure it is available for the fracture modifier though.

If I get you right, you don't need to disable fracture at all. I haven't downloaded an updated build for a while, but it is doable. You just want an object to fall to the ground, and stay intact until another object hits it, correct?

@DuarteFarrajotaRamos, that's a good point.  Although so far I haven't found anything like that yet with the fracture modifier, but I will keep looking.

@Timaroberts yes, that is exactly what I want to happen.  I just need to find some way to keep the object intact until it gets smashed after it hits the ground.

To achieve this effect you can use the Dynamic Fracture Mode for the object to be fractured. Note that the Dynamic threshold will cause the object to fracture on impact after falling if set too low. Make adjustments between this and the mass of other objects that interact with the simulation so that things work as desired.

The object that will fall onto this object needs to have a sufficient amount of mass in order for the fracture to work. Here, the sphere has a mass of 25, the rest of the rigid body settings are at defaults.
You may need to increase steps per second in the scene properties if the simulation seems to be unstable, just be sure that all transforms (rotation, scale) are applied.

alternatively you could still use prefracture and constraints with higher constraint search limit (per mesh island) and higher search radius (this depends on the object size). The more constraints you have plus maybe higher solver iterations lets the object look more stable. You can then control the breaking via angle for example. Additionally you could use autohide to let inner faces disappear as long as some distance threshold between is not exceeded. All this just in case Dynamic Fracture still makes problems :) It is not really intact until it hits something, but it looks intact.

This definitely worked thanks for the solution!

@scorpion81, it has worked with dynamic fracture, but out of curiosity, are you describing the effect of shards only appearing where the object has been impacted?  Not sure if I fully understand your suggestions.

no, the object would already be fractured into shards. The constraints just hold them together in theory until impact, but you then have carefully to adjust the settings to get the desired effect. Glad it worked with dynamic fracture though :) As a side note, with prefracture you could have used Extra Particles with one or more helper objects with particle systems, in order to determine where you want smaller shards, e.g. near "planned" impact points. This way shards farther away would be bigger, but still there. My suggestions were only thought as fallback in case dynamic wouldnt have worked.


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File size increases every time I save
It seems that whenever I save my file, it gets bigger and bigger no matter what I do.  Why is this happening?  At first I thought baking might have been causing the problem, then I tried reducing the number of particles (smoke) to something much less and it still produced a massively large file.  Finally, I simply saved it without doing anything to the file and it still grew to the same huge file size.  I've attached a link to the .blend.
.blend file
Thanks!

The Cache of ParticleSystem saves with the file (apparently).
Removing ParticleSystem from Sphere.001 reduces the file size. Reducing the Number of Emitted Particle from 500000 to 1 does the same.
Detailed Steps

Select Sphere.001 on Layer 2.
Go to the Particle System Tab. As you can see it has 20 users. Remove the particle system.
Select the other users and remove the particle system from each. Plane_cell.013
,Plane_cell.461
,Plane_cell.464
,Plane_cell.464
,Plane_cell.543
,Plane_cell.545
,Plane_cell.623
,Plane_cell.627
,Plane_cell.648
,Plane_cell.713
,Plane_cell.728
,Plane_cell.743
,Plane_cell.754
,Plane_cell.757
,Plane_cell.763
,Plane_cell.771
,Plane_cell.834
,Plane_cell.854
,Plane_cell.875.
They are easy to locate in the outliner, since they have the modifier icon next to their name.

While it is best practice to create a separate cache directory, you may have assigned the particle system to some objects by accident, thus increasing the performance cost (more particle emitting objects).

That's odd for some reason removing the particle system doesn't reduce the file size for me.  How do you clear the cache for ParticleSystem?

@lakerice I have added additional notes to the answer. Edgel3D answer also holds important information.

Oh now I see!  I have no idea how I assigned particles to those objects, but I'm glad I was able to remove them.  And yes, from now on I'm caching to a separate directory and it's working out great.

I observed this only last night!  I have two particle systems running and what was a half MB Blender file before the particles were added, suddenly increased to some unbelievable size! (can't remember, but it was huge!)  I then switched on the caching and nominated a spare folder.
No baking is involved and when running it, the particles ceased to appear, BUT - the filesize when resaved returned back to 600 KB.  I cleared everything including Blender's temp buffer, caching folders etc so when it was reloaded there wouldn't be any hangovers.
The particle settings I'd made were still intact, so I switched off the caching and everything returned as before, particles and all!
My procedure now for this particular project is, prior to a final save, tick the caching box for EACH EMITTER, then save.   When reloading, switch it off again.  No more humungous filesizes!
Note again - for this to work properly you must nominate a folder for caching.


text:
How to model a television dial?
I'm trying to model this dial and for some reason I'm totally stumped on how to do this without too many booleans and to make it smoother than the rest of the tv.  I've been watching tutorials, but the few I found were more how to make the a knob separately and from a side view rather than front (which is what I'm doing).
If you need the .blend I've attached it, but any simple example or tutorial suggestions would do...not trying to get anyone to do the work for me ;)
Here's the image:

And here's what I have so far with a boolean...I just have the feeling this is the wrong way to go about this:

A common way to do that is create a hole in the surface, add a circle into that space then fill in the gaps.
1 : Subdivide a plane and delete some of the inner vertices.
2: Add a circle with a vertice count the same as the number of vertices that now make up the inner edges of the plane.
3: Select both the circle and the inner edges of the plane, then using the W shortcut key open the Specials menu and choose Bridge Edge Loops.
4: Using the Extrude tool model the rest of the Dial.
5: Add bevels and or supporting edge loops, smooth….. etc  etc .
Note that if you intend to use a Subsurf modifier then aim to use a circle with less vertices than in my example below.

Check on Youtube for cutting holes in meshes. This is a good example https://www.youtube.com/watch?v=Bc52fcrHvAA

Nice one. We need more topology Q&A here. Beginners tend to attack such problems with booleans, based on the logic that real world sculpting mediums like clay work that way (just carve out or add to it!). I totally did this when I was starting out with 3D. I was really happy when I finally saw a tutorial that made topology click for me, and that marked a turning point in how I approached modeling. Because of this I am now a huge advocate of teaching topology (and I do). I am also still learning new things about it.

Sorry I didn't see this until now...wow this is definitely a cool way to go about it.  I do want to avoid too many boolean operations, so this is a great technique too.

I would make another object with "P" and then edit it as I like. You can also apply smooth surface setting on the left (when its separate object)

Ahh that works nicely...now it doesn't affect the surround mesh.  Thanks!


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Apply transform (rotation) to video clip before motion tracking
I have a video clip filmed on a GoPro in wide angle format.  I've figured out how to apply the Lens Distortion K1, K2, and K3 values which will cancel out the fisheye look of the video.  I drew polylines on the video in the Motion Tracking tab of Blender, and edited the lens distortion K values to match the contour of the polylines to features in the video.
However, the polylines do not match up properly because the video needs to be rotated slightly before changing the lens distortion.  I can rotate the video after applying the distortion just fine.  But I cannot figure out how to apply the rotation transform to the video before applying the distortion, viewing the rotated video in the motion tracker, in order to be able to draw polylines on the already rotated video.  Is there a way to do this besides rendering out a rotated video and loading it back into the motion tracker?

It's not that it doesn't work, it's that it's hard to decide which K values are appropriate when comparing against a polyline which is already crooked to begin with.  I can determine the correct rotation angle easily before the lens distortion since the fisheye effect is symmetric across the Y-axis of the image.  It is not symmetric after applying K values.
https://i.imgur.com/2bPE70b.png

Besides using division instead of polynomial, that's what I was doing.  Drawing a few polylines with the grease pencil, with some help from the grid.  Unfortunately, using the trackers to rotate the video also rotates the grid.  I was hoping to have the grid remain static while the video rotated underneath the grid so that I could determine the correct rotation angle.  Either way, I gave up on blender and wound up using OpenShot to defisheye the video because I got stuck.  Thank you for your help though.  I'm marking your answer as correct.

Blender 2.78 now has the ability to rotate videos in Movie Clip Editor in 2 steps.


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What are the best settings for a video export to Adobe Premiere (CS6)?
Whenever I import a video rendered in Blender into Premiere, the video in Premiere only shows a random frame from a different source for the duration of the video.
My current workflow (with workaround) is:

Put frames in Blender 2.75 video sequence editor
Render out animation with H.264 format/file format
Run through Handbrake (because when I put the file straight into Premiere the problem above happens)
Use the new Handbrake video file in Premiere

I need a way to cut out the Handbrake steps, does anyone have working render settings that I could use to export to Adobe Premiere?

I don't believe this is an option for me because when I tried to do this I only got a one frame sequence. I'm pretty sure it happened because the frames I have are irregularly (non-sequentially) named and this tutorial (https://www.youtube.com/watch?v=q9kH7R54tkU) says they need to be.

What I ended up doing was following cegaton's suggestion (I don't know if I'm able to say a comment answered my question) in which they told me to import the frames as a sequence.
At first I thought I was unable to because of the frame's irregular naming pattern, but then I found this thread (https://forums.creativecow.net/thread/3/926297) which suggested to do a batch rename in Adobe Bridge to give all the frames a consistent naming scheme.
To batch rename, open up bridge, select the files you want to rename (hopefully they are already in order) and go to tools -> batch rename.

i open the rendered h264 animation files from blender in windows movie maker save them from there, and then they'l work in premier pro. if i don't put them through movie maker first they just bounce right off prem pro, it says they are damaged, but after banging them through windows movie maker they're fine.


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Wind Field freeze at frame 250. Where can it be changed?
I have setup a project of 250 frames with a flag and a wind force field. It works fine until I change the length of the project to 520 frames, then the flag is frozen after frame 250. There must be a simple way to change this. Thanks for any help. Regards, Daniel.

Have you modified the length of the wind field to 520 frames or just changed the length of the project?


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Why images are blury when extracting image sequence from video clip?
I have an issue when generating an image sequence from a video clip.
Pictures 1,2,and 3 are three consecutive images from a video clip.
Picture 4 is a close-up of the heel of one of them.
The camera is on a tripod. As you can see there is no issue with the brick wall,
but with any moving part there is.
The camera is a Panasonic HDC-SD100. The clip is AVCHD 1920/1080.
If I use VLC to extract the image sequence there is no issue.
I use all the default settings except for the rendering resolution which I set
to 100% and image compression to 0%.
I have the issue with Blender 2.79b and 2.80.
With this image issue it is impossible to do camera tracking.
Any ideas what I need to do in order to solve this.
Best regards.

What you are seeing is the result of interlacing https://en.wikipedia.org/wiki/Interlaced_video

VLC by default will de-interlace the frames and use a blend algorithm. The movie clip editor in blender does not have any options to de-interlace or to interpret the footage as fields. So you will have to transcode the footage first to a format with no fields.

Does the camera have an option to work with progressive frames? If so, try using that instead. And maybe use a faster speed on the shutter to avoid blurry images. Blurry pics are hard to track accurately.

You need to deinterlace your footage. Try this checkbox in the bottom of the Source panel. and if this doesn't work, you'll need to deinterlace your footage outside of Blender first.

The sad part is that to do motion tracking there is no way to link the information from the VSE to the movieclip editor. And the movie clip editor lacks a de-interlace function. Importing to the VSE can be used  for exporting a clean version though.

Many thanks for your replies. I have study electronic and television end of the sixties, yes it is not yesterday. In the days of CRT screens interlace video was needed for the eyes. But for digital video it is not really needed anymore. I did not find the deinterlace option in Blender 2.79, but I did in 2.8.
So I did a quick test with 2.8 and it looks great. There you can see what I am up to https://www.youtube.com/watch?v=H1VTozUgvd4. There are two other cartoons.
Many thanks for your help. Take care, Daniel


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Can modifiers be computed and applied from the command line?
For heavy modifiers, the time it  takes to compute can range between a few seconds to half an hour or longer.
Can modifiers be added, computed, and applied from the command line with some sort of indicator of progress?
Running from the command line would be useful for running blender GUI-less without a WM to save memory.
It would also be ideal to have some idea of how far along the modifier is.

From you question its not clear if you want to create and apply the modifiers from the command-line, or just apply existing modifiers. If the modifier takses half an hour to compute I would guess you didnt set this up from the UI.

In my particular case I can set it up from the UI, as it only takes that much computation time with high settings (so I can disable visibility before setting it) But if it's possible, it would be good to add the modifier from the command line as well.

could you update your question then? For a good answer these details are important.

You'd have to use bpy.ops.object.modifier_apply, e.g.
import bpy

for obj in bpy.context.scene.objects:
    bpy.context.scene.objects.active = obj
    count = 1
    length = len(obj.modifiers)
    while obj.modifiers:
        name = obj.modifiers[0].name
        print("%s: Applying %s (%d/%d)" % (obj, name, count, length))
        bpy.ops.object.modifier_apply(modifier=name)
        count += 1
print("All done.")

For info on how to to run the above, see here.

Thanks. This works pretty well, but I was thinking of and indicator of progress per modifier. As mentioned by ideasman42, It seems this is not possible at the moment.

You can apply modifiers from the command line using a script, but there is no progress for each modifier.
Note that modifiers that take half an hour is not the kind of work-flow Blender is optimized for. If you are processing very high polygon meshes you may want to consider some tool like MeshLab to get them into a more usable detail level for blender to work with.


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Blender used by game designers?
I hope this question is relevant to this forum...I've had a lot of incredible help from people on this site and it's always been appreciated.  I actually just have a general question: is Blender ever used by large game companies or is it sort of like how GIMP is never mentioned for graphic design jobs but Photoshop is always a must?
I'm thinking about getting into 3d modelling professionally and I love Blender.  So I guess I'm wondering if it is necessary to have to learn more commercial, expensive programs as well?
Thanks!

No, the Blender game engine has had no major studios use it, it is nowheres at that level. I would recommend learning Unity or Unreal since they are now free to use.

I do not think this is a question for this site. Nevertheless you need to differentiate between Blender and the Blender Game Engine as these are two different things. Beside of that I suggest to ask the "large game companies" what tools and methods they use. As your question is more targeting a job there ... better ask what skills they expect from you.

On gamedev.stackexchange.com, searching for questions containing Blender brings up 251 questions and answers. That would be a better place to ask the question than here.

see also this quite recent interview: http://www.blenderdiplom.com/en/interviews/591-interview-aidy-burrows-on-blender-in-aaa-games.html

I remember this featured on BN a few months ago http://www.blendernation.com/2014/04/23/monument-valley-a-stunning-ios-game-designed-with-blender/

@m.ardito They used Unity, and only used Blender for asset creation.

Ah thanks I didn't know about gamedev.stackexchange.com

No, Blender has not been used by any big game companies to create games, and no well-known games have been created with Blender. (Unless I missed them.)
However, as an experienced game developer myself, I can tell you that many have used Blender for 3D modelling, and exporting the models into other game development tools such as Unity to create games using their 3D models.
If you're thinking of getting into game development I would recommend you join gamedev.stackexchange.com, and perhaps start off with a couple of YouTube tutorials on how to use Blender and Unity (or other software) jointly.


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Can't get my icosphere to render as a halo
Not sure why I can't seem to turn my selected object (icosphere) to a halo when I try to make a new material.  The options just aren't showing.  Thanks]1

You are using Cycles Render mode. Switch it to Blender Render and the options you want'll apppear.

But then how do I preview the scene in cycles with the halo effect showing?

Creating the halo effect like this in Cycles Render is not as simple as in Blender Render. Please see this answer to understand how it works in Cycles: http://blender.stackexchange.com/questions/27846/blender-cycles-wont-render-halo-particles


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Leaf variety in sapling addon?
I'm using the Sapling addon in 2.79, and I'm having trouble making the leaves look realistic.  As you can see in the screenshot (sorry for the forest HDRI in the background; I know it made the image a little obscured) every leaf is exactly the same, top and bottom, all the same size, straight, etc.  What I am wondering is if the following is possible:

Curved leaves
Leaves of varied sizes
Some leaves with one texture, other leaves with another texture (i.e. orange, red, brown, yellow for fall trees)
Ability to add bottom textures

All this is assuming you didn't convert it to a mesh and had to do all this leaf by leaf :)
Thanks, I really hope others can benefit from this post too!

Some of these I know for a fact are possible. The Leaf Object parameter answers 3 of your 4 questions. First, you'll need to create a leaf, either with a Nurbs Surface, or a simple mesh (either method will work, but if you plan on texturing the top and bottom differently, I'd go with a mesh). Then when you add your Sapling Curve, in the Leaves settings, set the Leaf Shape to "DupliFaces" and the Leaf Object to the name of the mesh you created to be your leaf. The varied leaf sizes has its own parameter toward the bottom right "Leaf Scale Variation". Unfortunately, the Leaf Object parameter doesn't allow you to add Groups of objects, but you may be able to use the a particle system instead to achieve color variation in your leaves. Hope this helps!

Amazing!  It worked!  Thanks so much.  The only issue though that remains is that I can't seem to make the leaves work with multiple objects...to get that variety of fall colours


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Mesh causing abnormal results with subsurf modifier
Probably an obvious answer, but I can't figure out why my mesh is causing such a weird crumpled up look with the subsurf modifier.  I've gone through to make sure there are no doubles or overlapping vertices, but it still looks weird when I apply the subsurf.  Any idea what I might be doing wrong?

Here is the .blend

Short answer:
Bad topology.
Longer answer:

You have here some non-manifold geometry as internal edges, badly made faces (one face across 3 prepared quads), ngons and for some parts you will need support geometry (to eliminate shading issues and hardening edges). Subdivision Sufrace modifier don't play along with those. You will need to have quad based topology with proper edge flow.
As for this particular question there is too much to cover on how to repair every broken part, I would encourage you to have a moment to redo the whole mesh having in mind quad based topology. Also, use Mirror modifier so you will not need to make changes on both sides (there are some differences now).
Look for example at this topology:

Also you can learn something from here: http://topologyguides.com/

You're right.  As frustrating as it is, it'll be a lot easier to start over again than to fix those issues.  I think a large part is that I am trying to fix things and making it worse.  A few of the most interesting parts of that guide you suggested is keeping quads square and letting modifiers take care of more complex geometry rather than adding too much manually, which is what I think I was doing.  Just out of curiosity, was the revolver you posted using a modifier on both meshes?

@lakerice revolver is from here: http://miriambonetti.blogspot.jp/2014/02/hard-surfacing.html but as far I can tell just by looking at it, the top mesh is without modifier and the bottom with. Also I don't know which software author used there, but it doesn't matter; good topology is good everywhere. There are mainly two most important things. Keep them quads and be aware of edge flow.


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Issue mapping baked material for LEGO geometry nodes
I'm trying to recreate the Lego version of this beach ball object, which has been baked (as geometry nodes cannot do multiple materials as far as I know).
The baked material is fine when not using the geometry nodes as you can see here:

However, when I use my geometry nodes, the UV map appears all wrong (even though I unwrapped the object before baking (btw, I am using SimpleBake add on). I know you are supposed to use instancing for the material, but nonetheless it won't distribute the material properly:

Any ideas as to why this error might be happening? FYI I am using 4.1.1 if that helps.
Here is a link to the .blend file: https://drive.google.com/file/d/1uHhGB_Wo2dY40ZQLM0HKHBXm2D6t7iZt/view?usp=sharing

You have stored UV map as float, change it to vector:

That worked! Thanks so much!


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Materials: How to get this transparent screen look?
Alright Im trying to get something along the lines of a mix shader with image texture combined with emissive but transparent - these screens:

I have no idea how to go about this in cycles. What would create this material?
EDIT: this is what I have but not as desired:

Just an image texture and emission mix shader - I do not know how to implement transparency into that and not achieving the right look. Im new to nodes

@cegaton ^ What would you suggest from here?

if you already have an emission shader and mix shader, just add a transparent shader and then slide the bar to taste.

@icYou520 see edit - the transparency won't work

Why do you have the animation-nodes tag?

Delete the Diffuse shader and one of your mix shaders, plug in the image directly into emission shader, connect the emission shader and the transparent shader into the mix shader, Adjust slider to taste.

This effect could be achieved with 4 nodes.

Add a emission shader (that your image will plug into)
Add a transparent shader
Add a mix shader

Plug your two shaders into the mix shader and slide the FAC value to taste.
After rendering I would bring the image into a compositor and add some glow around the hologram image to make it a little more believable.
Pics taken from Unsplash.com
Photo by Javier Ramos on Unsplash
Photo by Justin-Lim-500765-unsplash


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Material question - how to make this reflective?
Ok, I have a diffuse/emissive material applied to the large blue cube below:

This is created with these nodeS:

Ive tried adding in some sort of glossy node but am not versed with in depth making materials- I need the large blue glowing cube to also REFLECT the glowing things/lights around it (i.e. the emissive ring)
I need it to have some reflection like the black cubes do. How can I integrate this?

The problem is the emissive shader doesn't really work well with the glossy. What I think is happening is the emissive texture is taking all of the light that is reflecting into the camera. It is basically bleaching out the ability for the light to reflect and is making it difficult if not impossible to see the small amounts of light reflecting off. to fix this, I recommend that you basically reduce the amount of emissive compared to the glossy so that it's not for the lack of a better word overshadowed. I did a test render here. It appears to work but it might not be exactly what we're looking for

We will also expect any emissive object, which is not a lamp, to be translucent, because we expect the light source to be inside of it. And translucent but not transparent objects will be very rough on the surface and subsurface, which would appear extremely diffuse. So next to a difference in intensity, which you fixed, the combination of glossy and emissive simply doesn't correlate with our vieweing experience and expectations.


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How to get mist only at horizon line?
Ok I am trying to create something like this - where there is a "layer" of mist that occurs only at the horizon line -

I have glowing objects in my scene that create a glare and Ive followed tutorials to get mist, however it covers the ENTIRE background, not just a line in the center.

What can I do to get the horizon only mist?

Use a mask to limit where the mist pass is combined.

you could put a plane and play with its transparency

@moonboots what do you mean exactly?

@sambler sorry, not great with nodes, do you have an example of exactly where to put it - I connected it where the mist comes out of render layers, and this works, but I need some kind of blur to make it not as sharp - where would I do that?

@skyguy add a box mask node and connect it to the fac of your alpha over. Add a distort->Rotate if you need to adjust the angle.

Skyguy, here is what I meant:

Create a plane, give it an Image Texture and paint it in black and white.
Change the node organization: Plug the Image Texture you've created into the factor of a Mix shader so that it separates a Diffuse (or Emission) node (probably white) from a Transparent node (make sure that this Transparent is 100% white which doesn't seem to be the case by default). Add a second Mix shader to give transparency to your diffuse, plug it into the Output.
Now you have a plane which creates a mist. It's a much lighter solution than Mist or Volume Scatter (well, I guess...). It won't fit everytime though, as it's a fake 2D mist. But for example if you want your camera to rotate around the scene you can paint on a semi-circular or semi-spherical surface instead of a plane, etc.

Perfect. thank you so much, seriously. Tangent but is there an easy way to have this billboard - so it always faces the camera?

as I said it's a fake mist, so you have to find tricks, for example if you want your camera to rotate you can paint on a semi-circular surface instead of a plane, etc.

I just had a very similar issue. I wanted a nice fall off in the distance for a jet scene flying over water. What I did was to use the mist pass, set the start so it was just beyond the jet, then the depth finished just before the edge of the ocean plane. Then I cranked up the strength in the compositor using a map value. It didn't hide the join between the ocean and the sky completely but it helped a lot, specially with DOF on the jet.


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How to rotate object on axis (planet)?
Ok Im not sure whether this has been addressed specifically but I have some planet orbit rings that I need to rotate ON the axis, meaning they stay at an angle but rotate -
so far Ive parented the ring to an empty and am just rotating the empty which results in this (NOT good):

The tilt should always be more/less like #1 - how can I do this?

I think to achieve this, you need to change the transformation orientation from global to local

To achieve this particular rotation, you need to change the transformation orientation from global to local
Then if you press R to rotate and then Z twice, you will rotate the object on its local Z-axis. You don't have to have changed the transformation orientation to achieve this, it just help visualise the axis you're going to use

Hope this helps.

Sorry - did that but still waving around/ not going locally

Try rotating it on other local axis apart from the Z


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How to render WITH the default checkerboard as background?
Ok there are a ton of questions on getting a transparent background and NOT having background be checkerboard in final render, but what if you WANT this checkerboard pattern as your final background?

Ive tried unchecking my Transparent box - I'm in cycles.

How do I get that as png? Isn't it stored somewhere?

You would need to create it like any other texture you would want to use in the background.
Here I did it for you. I made it tilable too.
Shift + A > image as planes.
Then put it as your Background (Probably shadless is best option for this).
EDIT:  OP wanted it animated.
Ok I will solve it 90% of the way for you.
You will need at least a 4K Texture for this (So I created it for you, 1 small problem, we will get to that shortly).
Here is a link to 4K texture (MODS not sure where I should put this.)
https://drive.google.com/open?id=1D_FiZ92xwt7m-gWxbS6p2S7x4XrNobpA
Set it as your environment background.
*If you are using an HDRI you will need to set up the nodes like below so you can see the image of the BG you want but have the lights and reflection of your origianl HDRI.
The problem with the 4K texture is that it needs to be "Spherized" (I think I just made that word up). I didnt look how to do this in Photoshop that is why you see the squares stretched a little in the GIF I provided. I also provided what an HDRI should look like so it is wrapped around the world correctly. I know how to do this in Blender (Panaramic, Equirectangluar) but havent looked how to do it in Photoshop.
If you look at the gif you can see the checker BG change from the OG to the one I made, Its real quick.
Keep in mind the texture will be turning with your camera, not like how it stays static in the viewport. This can be distracting.

This is not a real HDRI this is just what they look like HDRI HAVEN

Or you could just make a huge sphere to cover everything in your scene (might cut off some of your sun lamps) apply the texture to the sphere and make sure you have your lights and camera in the sphere.

Thanks, but I'm panning around in my scene - a single image plane won't work. How do I tile the background image because setting world background to image as this Just makes it all gray

Edited answer!!

Here's a solution using a Checker Texture for the Background material using Window coordinates. It's not perfect but I think gives a pretty good impression.

You'll need to adjust the Mapping node to match the camera aspect ratio.
This essentially just textures the environment using a Checker texture mapped based on Window coordinates, and only for Camera rays.

would this move with the camera/look static?

@skyguy Since it uses Window coordinates, moving the camera won’t affect the position or orientation of the squares in the frame - it will behave the same as for the real ‘transparent’ checker effect with the squares moving with the camera.


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How to key out a white background in compositor?
I've been trying for hours to remove my white (well, grayish white) background from a video, and I thought you could remove it with keying nodes in the compositor (cycles).  I managed to get somewhat close, but it still has pieces of white, and it affects the colour of my sunglasses.  I've tried tutorials meant for green screens, keying/chroma/difference/luminosity nodes, but I just can't figure out the right settings.  Core matte mask helped a little, but made it impossible because my body moves in the video.  I played around with the keying colour a lot, and nothing seems to help.
Is this possible or is a green screen absolutely necessary?
I've attached the .blend file with a screenshot rather than the whole video due to file size, but I imagine it's the same principle.
Here's a screenshot of the original image:

Here's the node setup:

Thanks in advance!

as you can see, with this setup you get pretty far.
Of course you should mask out roughly your body before, so that it won't "hurt" your face ;)

Thanks!  Seems so simple and effective.  Only thing is, I move in this video...if I mask the body, how could I make it so that it doesn't cut out when I move?

If you move you have to use the tracking feature of the video sequencer - but this is a second question...

Ah thank you! I'm learning about that now.


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Copy rotation does not always rotates correctly
I have created an ostrich and this is the armature.
The feather bones, 5 left, 5 right and one centre are controlled by an IK bone.
Bone naming is done view from the back of the ostrich, so left and right are correct.
The whole armature is controlled by the MAIN bone.
Every feather bone has a copy rotation constraint for the ‘X’ axis.
The 5 left ones have a copy rotation constraint for the ‘Z’ axis with and influence of: 0.2, 0.4, …, 1.0.
The 5 right ones are like the left one with the ‘Z’ axis inverted.
Picture 1 : The feather bones, 5 left, 5 right and one centre are controlled by an IK bone.
Bone naming is done view from the back of the ostrich, so left and right are correct.
The whole armature is controlled by the MAIN bone.
Every feather bone has a copy rotation constraint for the ‘X’ axis.
The 5 left ones have a copy rotation constraint for the ‘Z’ axis with and influence of: 0.2, 0.4, …, 1.0.
The 5 right ones are like the left one plus the ‘Z’ axis inverted.
Picture 2: the IK ‘Z’ axis is rotated clockwise and the feather bones tilt correctly.
Picture 3 & 4: now we rotate the MAIN bone CCW or CW and the left feather bones are still OK.
But the right ones are not correct anymore.
I have the same issue with the wings. In the case of the wings, it is the right side that does not work.
What did I do wrong?  How can I correct this? I have the same issue in Blender 2.79 and 2.8.
Many thanks for your help.

It always works correctly.  It does not always work like you'd expect.  The differences are basically down to how Euler angles operate, especially in conjunction with constraints.
So when you copy rotation, here's what it does:

It decomposes your target bone's orientation into XYZ Euler triplets.  These are not necessarily or even likely to be the same XYZ triplets you keyframed for that bone.  That is because Euler angles are aliased: there is more than one set of Euler angles that corresponds to any particular orientation.  But in order to accommodate space-switching, we have to get only a single set of numbers out, so there's some information that's lost.

If you want to see what these anti-aliased (not a good thing in this case) numbers are, you can duplicate the control bone, give it a copy transforms constraint targeting the original, and then apply visual transform (or bake animation.)  You will see that the transforms you get are probably not the ones you expected.

We multiply the components of that triplet by the influence of the constraint, and then rotate the constrained bone with it.  Changing influence does not give you rotation along a plane-- rotation in a single axis.  That is, there's torque.  That's because Euler angle rotation doesn't interpolate in a straight line.

Those two things combined mean that copy rotation, particularly at influence <1.0, particularly for 2-axis copy rotation, doesn't work like people intuit it ought to.  Copy rotation is part of a set (with limit rotation) of the least intuitive constraints, because of how people think about 3D angles working, and the differences between that and how they actually work.
If only the first thing is a problem, you could consider using a driver instead of a constraint.  If you don't need space switching, drivers can let you work on raw, no-lost-data f-curve numbers.
However, what I'd generally say is, try to find a different way to do what you want.  Copying rotation of 3 axes, at influence 1.0, is perfectly safe.  Damped tracking and locked tracking with influence less than 1.0 is safe, and operates in the "swing angle" (smallest rotation) rather than with any torque.  One way that should get you what you want is to copy all rotation fully, and then restore a part of it by damped and locked tracking non-deforming marker bones.  That may be more complicated than what you actually need though.

Nathan, thanks for your reply.
In order to make simpler for investigation I have created two new bones.
One bone for controlling the feathers on the right and the centre one.
The other for the feathers on the left.
The bone on the right is the “master” and the one on the left the “slave”.
The “slave” has a copy rotation constraint, one for “X” and “Z” of the “master”. “Y” is not needed in this project. It still did not work as I expected. All this was done in Blender 2.8.
After much researches, I decided to open a copy of the blender project with version 2.91.
I have noticed that the Copy Rotation Constraint panel has change.
When using Local Space for Target and Owner it works like I was expecting it.
I have saved the file in 2.91 and reopened it in 2.8 and now it also works in 2.8.
It is beyond my skill to now why it works after that. I will do the same for the wings.


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How to give UV mapped textures normal maps?
Whenever I apply UV textures to a mesh, the texture looks flat after I rendered it. How to give it normal or bump maps? im doing animations cinematics not a game.

internal renderer.

You need to use a bw version of your colour texture and use it to drive the bump map value in the texture slot. http://blender.stackexchange.com/questions/33756/how-to-make-this-kind-of-texture-in-blender/33785#33785


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How to separate an armature bone from an armature bone in an animation?
Im doing an animation that uses a hand and a sword. The hand swings the sword alot thats why there is a bone from the hand connected to the sword, but problem is, i want to throw the sword in my animation, but I dont know any way on how to detach the sword from the hand.

The sword it´s a part of the mesh? Just go into edit mode select the mesh from the sword and press "p" then hit "selection". Now your sword it´s a object a part from the hand, if you have the animation ready it will keep the animation now you just need to animate the sword be throwing.

If you want to separate the bones:
• Select the armature;
• Enter Edit Mode;
• Select the bone you want to separate;
• Hit "p";
• Click Separate bones.


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Duplicating ALL of a Hierarchy - selectable or not
Heres what I need help with.
Say I have an Object in the Outliner, it has children. Some of the children in the outliner have the pointer (object is selectable/non) turned off. I need some of the objects selectable and some not for animation purposes
Right click>Select Hierarchy only selects the children objects that have "selectability" turned on.  Same for Shift-G
When Duplicating the parent object, I want a way to have ALL of the children involved in the duplication, without having to go in and manually turn on "selectability" for the children objects who have it turned off. (and then have to manually revert all the ones who need to be reverted.)
I often forget that there are children objects and sometimes end up with duplicated objects that are missing some pieces...
Does this make sense?
thanks!
jd

If you had a script turn on all the items to be selectable, would you need to disable them after duplication, both in the original and in the duplicated set?

Here's my solution. The script starts with the selected item and iterates over each child object (recursively to include children of children). If the child object is set to non-selectable, it changes the object to selectable, adds a flag to the object for later, and also adds the object to the current selection.
After duplication of the group, the script iterates through both groups and checks for the flag set earlier. If it finds the flag, it make the object non-selectable again.
import bpy

def CheckSelectStatus(p):
    for c in p.children:
        print(c.name)
        c['hideSelectWasTrue'] = False
        if bpy.data.objects[c.name].hide_select == True:
            bpy.data.objects[c.name].hide_select = False
            c['hideSelectWasTrue'] = True
        c.select = True
        CheckSelectStatus(c)

def RestoreSelectStatus(p):
    for c in p.children:
        if c['hideSelectWasTrue'] == True:
            bpy.data.objects[c.name].hide_select = True
        RestoreSelectStatus(c)

#---------------------------------------------------

#get our selected parent object
p1 = bpy.context.active_object

#iterate through children and make selectable and select them
CheckSelectStatus(p1)

bpy.ops.object.duplicate()

p2Name = ""

#iterate through selected objects to find duplicated parent object
for obj in bpy.context.selected_objects:
    if obj.parent is None:
        p2Name = obj.name

#iterate through original group and disable selection
RestoreSelectStatus(p1)

#iterate through duplicated group and disable selection
p2 = bpy.data.objects[p2Name]
RestoreSelectStatus(p2)

You are my hero!!

To paraphrase Jack Nicholson in that movie.. "You make me wanna be a better scripter"      This works perfectly. Have been knee deep in my project all day and your script has come in handy 20+ times already and saved me at leeasst a hour. How do we get this into the next version of Blender as a standard tool called "SuperDuperlicator"?   thank much again Mr Todd.       you the ant!

Your welcome. Never been called "the ant" before! : )

Is a reference to a movie, (" Ants " I thiiink )

Is a line form that movie, (I think) All the kids I work with use it


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GMIC FILTER OVERLAY?
Look at https://www.youtube.com/watch?v=MYhDis257gc In the link, it shows the GMIC FILTER OVERLAY effect... What is that? I mean, what does it do, and how can I use it? Does it come with blender, and if not, how can I enable it?
I've searched for YouTube videos on the subject, but nothing appears... I'll try Blend Swap later, if no one can answer me here. I have several renders I'd like to apply this to, so any information is appreciated!

This appears to an effect in GIMP

Gimp? How do I use that?

It is a free open source image editing program. Look up GMIC OVERLAY on google, the effect should come up. Download GIMP here

Welcome to Blender.SE Joey, we hope you stick around to contribute and learn!  We do like to restrict our scope to things that directly relate to Blender though, hence this question was closed.  But here is a link to an article about G'MIC, it seems to be a filter for Gimp.


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File-based inputs to rigid-body animations
I would like to specify the motions of a rigid-body in a blender scene using 3-component acceleration data (or velocity, or displacement data) that I read from a file. That would allow me to record motions in the real-world, and then, later, animate them in an object in a blender scene based on the recorded motions. I see that I can animate rigid-bodes in blenders scenes with the mouse. Is there a way I can animate objects with file-based data? Do I need the game engine to accomplish this?

so basically , you have a motion capture and you want , lets say a cube , to follow the mocop?

Yes, for this application I want to use motion capture from a phone with an accelerometer. I don't know the term mocop, but I think you understand what I am trying to do. Let's say want to animate a martini shaker in blender. First I create a blender scene with a martini shaker, and ice cubes in it. I have a separate iPhone app that collects data. The user shakes their phone and I collect the data. I transfer the data from the iPhone accelerometer to my mac, as a file. Then I use the recorded data to animate my shaker in my blender scene, like the user shook their phone.

ohh i see i see , so its a transferal to blender ?

mocap means motion capture

yes, a transferal of capture motion to blender. One reason I'm interested in using data-files to move rigid-bodies in my blender scene, is so I can repeat exactly the same motions to the scene, and evaluate how different rigid-body physics settings affect the response of objects in the scene.

i see , I think you could do that by making the object you want  a child of the armature

Rigid body objects can be controlled by keyframes, so you could use python to read the file and create keyframes accordingly..


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BGE How do I get a objects location/Rot/velocity into a property?
I am working on a space game, no gravity, no friction, just a ship and lotsa things to avoid (rocks/aliens) all logic bricks.
How do I send my ship's current (updated constantly) location or rotation into individual properties?   i.e. X, Y, Z, XRot, YRot Zrot
I want to use these numbers to determine my ship's current velocity and location, combine the results with a collison sensor and then I can determine/set whether or not the ship hit a rock/planet hard enough to explode.
(slow = bounce  ---fast = Boom ---real fast = Rock and Ship go Boom)
This screams to me to be a python solution but that is outta my league to write, i have had some success dissecting and reworking existing python tho...
thanks for any pointers/help
jd

If you want to do it all in logic bricks, I believe it is not possible. I'm fairly certain a python script must be used.

With python a python script u can pass the values to a object game engine property to work arround logic nodes (i suppose).
from bge import logic
def main(cont):# cont = currentController
    x,y,z = cont.owner.worldPosition # owner = your ship
    cont.owner["Xpos"] = x # Xpos = object game property
    cont.owner["Ypos"] = y # Ypos = object game property
    cont.owner["Xpos"] = z


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“Cleaning up” meshes for unity: Necessary? Best practices?
I'm working on some low-poly assets in Blender with the goal of bringing them in as OBJs to Unity.
My question is about mesh preparation.
In edit mode, under the “Clean up” menu, I see:

Specifically:

Delete loose
Make planar faces
Split non-planar faces
Split concave faces
Fill holes

Questions:

When prepping meshes for Unity, should I be using any of the above options?
Should I triangulate my meshes in Blender before export (perhaps, using the triangulate modifier)?
In general, what process would you recommend I follow in order to get the best-looking mesh imported into Unity (and/or other gaming engines).

Thanks for your time!

Not exactly a question if i read it right but more of an ask for advice. But i'll just give some anyway cause why not right. Anyway, i make the models for a game i'm working on, also low poly, what i usually do is just make the model, name it, remove doubles, check the normals, add the collision mesh, and make sure no modifiers are not yet applied.

Thanks Luka! I really appreciate the reply. That's great advice. Do you happen to know of a better place where I can ask this type of question? I am definitely looking for advice on best way to prep my meshes before export. Thanks again!!! :)

Don't know of anywhere else but the offical unity forums/Q&A site, but that place is full of 10 year olds and is hard to get good answers. Also, another thing, i find the model type FBX works good for my models. But this is all personal preference.

Thanks again for reply/help! I think I know what you mean about the Unity resources ... I suppose there's www.blenderartists.org, but I'm not sure if my skill level would fit in there (I'm still pretty new to Blender). I'm a huge fan of list servs... I'll have to look around. Thanks for tip on FBX! I'll check that out! Much appreciated! :)

blenderartists.org Could work, i sure they wouldn't mind a few questions if you can find the right section for them. Good luck with your model and game! :)

Thanks Luka!!!! Hope to see you around the net. Good luck in your game/3d/art endeavors as well. :)


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Hair is not visible in Object mode (Cycles and Eevee) - Blender 2.82b
On Windows 10 in object mode strands have become invisible, but still renderable in render mode. On my working iMac everything is fine with the same blender file
In particle edit mode children hairs are not visible too.

Managed to fix it by switching to Eevee and selecting Strand instead of Strip, and switching back to Cycles


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Cut doesn't work on particular angles view
I got a strange issue tonight. When i cut edges under a narrow angle it works well, but when i do it from the top view (perpendicularly), it doesn't show me the cut marker point (but it still cuts). Could anyone give me a clue how to solve it?

I've noticed that sometimes the knife seems to "catch" on geometry clipped by the camera. Try setting the camera start clipping to 0, or switching to perspective when you can.

@SilverRain Thanks for your tip, switching to perspective view solved the problem - i am able to select any of the edges now. BTW setting start clipping to 0 does some strange stuff: https://i.imgur.com/cyTrvel.png and makes blender almost unusable - when I try to zoom the model out, it throws me far away from it:)

Another clue - this can be caused by the clipping tool (Alt+B) i use to see the internal part of my model

If I add that as an answer, will you accept it?

@SilverRain Sure! That is a pretty good solution

It's not too tough to solve this problem by switching to perspective view. This helps keep the knife from "catching" on geometry that you cannot see.


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How to make blue hot metal
I made this fire/hot metal node setup and can't figure out how to change it's natural colours to blue.  I tried colourizing the image texture (lava was used) but it didn't work.  Also tried using RGB to black and white with the image textures and playing around with hue/saturation, but nothing will change this natural hot metal colour.  I would post the node setup, but it was way to big to show in one picture.  However, I have posted the .blend.
Thanks

In base colour frame change Blackbody node to RGB Input or just disconnect Blackbody and set the colour in MixRGB socket, or set Blackbody to high value.

That worked!  Perfect solution


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Absolutely no light showing...totally at a loss
Really can't understand why I can't see anything.  Tried moving lamp and camera, increasing strength, but nothing.  Can't even see light in the lamp preview.  I'm pretty new to Blender, so I feel like I must've done something accidently along the way.
http://www.pasteall.org/blend/38975

It renders for me and the result can be seen. Probably it's not as expected because your lamp is almost inside of one of the cubes, but still you should see something in scene.

Same here, works fine. Something else is off. Maybe graphics drivers? Can you render anything at all? New default scene with cube and single point lamp? Anything in cycles?

Turns out it was a background issue!  Didn't realize that heavily affected lighting.  I don't even use lighting anymore for this project.

It seems fine for me, I get quite a neat render.
But if you want it to light up all of the boxes, just change it to a sun lamp.

If this is not what you were asking for, or I am not clear, please tell me.
Thanks!

Hey no you guys were totally right.  It was a lighting issue, but also I found out it was a background issue!  I guess being a noob, I didn't realize that having a black background would actually affect the lighting on the object itself.  I thought it was neutral.


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Why does fire take so long to render?
This is actually more of a general question, but why does fire take much longer to render despite baking?  I've done a lot of reading about fire/smoke simulations and liquid, and even at only 128 resolution (for the fire domain) and 500 samples (at 1920X1080 and 50% camera resolution) each frame of my scene takes about 30-45 min to render with a Nvidia GeForce GTX 860M GPU.  It's not so much a complaint as wondering if I am missing something or if this is just the way it is?  Hopefully this could help others who are working with fire/smoke simulations as well.
If you require screen shots or more info let me know.
Thanks!

Because fire is a volume, and volume rendering is slow. First of all, the baking you did doesn't help with rendering, it just caches the simulation itself. Anyway, the problem with rendering volumes is that you can't just sample the shader once at the surface like you can for solid objects. To render a volume, you need to evaluate the shader and sample what light is available multiple times along the transit through the volume. The finer the detail in the volume, the more steps you need to sample. The distance between steps in controlled by the "step size" attribute:  The distance is in meters, although the property doesn't show as distance for some reason. You don't need a step length any smaller than 1/2 the size of the smallest volume detail. For a smoke/fire sim, that would be the size of your voxels. You can find this for Blender's smoke sim by getting the dimensions of your domain, and plugging the length of the longest size into the formula: voxel size + length / (base res * (hi-res level + 1)). So a 10m domain with 80 res and 2 hi-res divisions would be 10 / (80 * (2+1)), or about 4cm.
There is also a "max steps" option you can use to force it to stop at some point along the path, although I'd recommend avoiding this control. Running out of steps mid-volume can potentially give some weird shading.
Additionally, if you're using the volume scatter shader, rays can be scattered (aka deflected) during the volume transit. And if your volume bounces is set greater than 0 under render settings > light path? That scattered path can scatter again. So higher values for volume bounces can increase render times a lot. Too few volume bounces can lead to dark volumes, especially for highly reflective clouds such as water vapor. You can compensate for this by adding some (more) emission to the volume if needed.
One way you can optimize a bit for smoke and the like is to prevent the shaders from running if the density is below a certain threshold. The node setup looks like this:
If the density is below the value set in the "less than" math node, it will output 0, causing the mix shader to switch to it's second socket, which as no shader. Thus, the volume closures are only executed if there's a enough density for it to matter. Figuring out the proper value for the less than node might take some trial and error.

WOW did that ever help...haven't gotten to the scatter thing in nodes yet, but the step size made a HUGE difference.  Thanks so much for this much needed info

Firstly simulation baking and rendering are two different steps. Baking a simulation calculates where the smoke is at a given time, rendering turns that simulated data into a visual representation.
Smoke and fire use volumetric data, which is a block of space that adds calculations to the render.
Start with a simple render, from the camera a ray goes out and sees the monkey, then bounces into the sphere and goes off to find a light. How much of the sphere reflects on the monkey? how much light bounces onto it at that point?

Now put a fire in front of the monkey. As the ray is passing through the domain, how much smoke is there? how much fire? how much fire is seen through the smoke? how much of the monkey shows at that point?
That all needs to be calculated multiple times and added together as the ray passes through the domain.

It isn't hard to see that volumetric rendering can add a lot of time to your render.


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ID Mask won't render composite properly
I've been trying like crazy to get my composite node setup to render the exploding objects (pass index 1) and I really can't understand why my ID Mask won't render them.  Instead it renders the entire thing in a bluish green hue.  I just want the objects with a pass index of 1 to look like that.  It's been difficult to get any answers via pictures since my node setup is pretty big so I will provide a link to download the .blend file so you can see the nodes more clearly.
https://drive.google.com/file/d/0BzCN0fElYa3Ha1FGZ1JBTnJ6M3M/view?usp=sharing


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Rendering two layers simultaneously glitch
I've done a render where I had the main objects on layer 1, and an explosion on layer 2.  However, when I render them simultaneously, the exploding pieces in layer 2 go right through the object in layer 1 (as the camera zooms through the object), creating a weird glitch like this:

I should mention the explosion has several composite nodes like glare, lens distortion and emission, so what I think happened was that the pieces on the 2nd layer went through the first and ended up illuminating the object in the 1st layer.  This also caused the render to be about 5 hours!
This is what the object looks like with both layers BEFORE the camera gets too close, thus not causing that glitch:

The reason I used 2 layers to render at the same time was so that I could use a set of composite nodes for the explosion only.  I didn't want to render them separately because I still want reflections of the exploding object to show on the objects in layer 1.
I'm guessing the only way to avoid this weird 5 hour glitch is to make it so that the explosion can't go through the objects in layer 1, but rather bounce off like they should in normal physics. How could I do this and still have them on 2 different layers?
For the blend, you can download it here (it was too big for blend-exchange.giantcowfilms) https://drive.google.com/file/d/0BzCN0fElYa3HUzhCT21yT3FPZ0U/view?usp=sharing
Thanks

You can simply use object index
This way, you can put all the objects on one layer, and still separate them for compositing.
It's easy

Switch your objects pass index.
Enable object index pass in the render passes
Use an ID mask node to create a mask of those objects.

Keep in mind
You can then try something like a mix node in the way shown to separate those objects on a black background. Keep in mind, that the output of the ID Mask node is like an alpha mask. Wherever that object is in the render, the output will be 1, wherever it is not, the output will be 0.
See the illustration below.

Here is an example of using this method to apply an effect. (the image shown under the composite nodes is the original.)


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alpha channel in image when compositing in cycles
I have two images that i'd like to overlay, the picture that is above is a point density picture that i saved in png so that it would support alpha channel,when saving it i could see that in color view it had managed to have the point density, but turned black when i saved it,but i think it still has the alpha channel in it. What node settings should i make to the alpha/transparency to be seen. this is how far i have come with my settings but i don´t know what else i should do.

Related: https://blender.stackexchange.com/questions/1801/using-alpha-channel-of-generated-images-for-cycles?rq=1


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Can´t get rid of object in render window
The white square and a couple other objects seem to stick in the picture, what ever i try to make them not seen, as my intention is to make only the white cloud visible. In the outliner i have tryed to restrict eny rendering that i just can find of any object from all scenes and as the cloud is a point dencity i have tryed to make the particle render not to render the emitter, i think i findt what object the white square is and restricted both, the rendering and scene visibility, but nothing seems to get rid of the objects´s. Any suggestions what it could be would be appreciated.

Please upload your blend file so we can have a look for ourselves

I think i solved the problem .


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My cycles settings have disapeared
for what i understand my cycles settings should be at the bottom of objects menu ,
but it´s no where to wound, i have cycles set as renderer, what could be the cause of this .
I have looked it ewerywhere but don´t findt it

Make sure to select any mesh object first. Probably Cycles settings rollout isn't displayed as you have camera as active for example

As @Mr Zak suggests in the comments, the Cycles Settings panel does not show in the object properties menu if the active object is a Camera, Empty Object, Lattice or Forcefield; regardless of how many objects you have selected.
Although it is not 100% clear from your screenshot which object is the active object, it appears that you have several Empty's in your scene which may be the culprit, if not the camera.


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depth of field to work not working
I have blender 2.78 and I am trying to get the depth of field to work, but I just can't make it. I think I have all that as needed the camera and the target  an object, the compositing is on, I even have the cameras limits set to the target object, I tried to render it in blender internal, in cycles and in the 3D window, but nothing seems to work. I'm wondering is it possible to get the dof to work without using nodes and if it's possible what should i do.
I now try to add more information that i think is needed. I have set the measurement system to metric in the scene , and the object that is the target has the value of 1.0 as size. the camera I used is canon aps-c. I  have tried different focus-stop values that seemed not to help. I'm not sure what the lens is that I'm using, or where to find the lens used ? I wonder that if i have difficulties with this because I can´t somehow set the right distances between the camera and the object and do nut fully understand the relation between the metric grid, object size, and the distances and adjustment´s needed to make the depth of field seen. I have read many depth of field tutorials, but I seem to miss awarness of something very essential to get it work. I have NOT been using nodes when trying to do this .

Check dimensions of your mesh in metric length. You can't get blurry effect if your camera aiming object that too far.
To make it work without scaling down your all object, lowering the aperture rasio of your camera.
example, i create mug and in metric length, it has 3m heights. then i set aperture to f-stop with 0.8 number rasio in DoF section.

This does not provide an answer to the question. Once you have sufficient reputation you will be able to comment on any post; instead, provide answers that don't require clarification from the asker. - From Review

Can you please edit this, and make the answer clearer.

If you make your aperture smaller by reducing the F stop, you can get less depth of field (more blur).
To read more about depth of field, read this question: https://photo.stackexchange.com/questions/2/how-can-i-maximize-the-blurry-background-sharp-subject-bokeh-effect


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Single image is not being saved
When I try to render an image operating in from the info menu, it will not make a still render, it seems to render the same still image over and over like an animation not stopping, it renders it then instantly start´s to render again. and it will not render it in the tmp on c: that it usually does, for some odd reason in cycles it render´s a still picture but in blender´s own render not !
i have set it to render from frame 1 to 1 but does not help . what could be a reason for this behavior ?

When you render a still image, you need to manually save the result, only using render animation automatically saves to disk. How many render layers do you have? A new render is started for each render layer, with each normally having different settings.

thanks ,this cleared the table, i had downloadet in my scene a foreing model and it had inside it settings that im not used to, and this caused the confusin rendering , but it=s ok now.


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particle keeps hanging in air when rendering in sheep it

I'm trying to render my project in sheep it render farm , but seems that when i render , the particle systems seem to keep hanging in the air where it should not stay. It is supposed to come in front of the vehicle as a dust cloud .  I have baked it in "bake all" , and baked it as a single object, but i have now tried 3 to render it in sheep it , and the particles keep hanging in the air.
Is there a possibility to render the particles separately with a render layer later or any other mean to get it to work .

are you using the same version of blender for your scene than the one used in sheep it?

the version is the same,, but now i wonder that could it be that i should enable the sheep to allow gpu rendering ,, seems that it´s not on . ???would that make the difference ..

no it won't. There's something else going on here. may be look at the hash of the blender build and compared between the two: https://i.sstatic.net/OPtq9.png

hash´s are identical 5bd8ac9 .

and this is rendering fine on your blender instance right?

Yes , when i made test renders with the same file that i send to sheep it i don´t get the problem and it renders alsow the second particle system, not seen in the sheep it render and this picture, it sould be on the back of the vehicle! so the other particle seems to disapier and the other is in wrong place . the Bake says it has 900 frames in .....

i uploadet the whole project i guess ,, but should i somehow upload differently the baked dynamics thats what i liket to know,how to you zip cache ?


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How to move the hook with a curve
I know how to move the curve with the hooks, but is there a way that hooks that are assigned to the curve , are moved by the curve.

using both a vertex parent and a hook together seems to bring undesirable results, but using the vertex parent is taking me to the right direction of what i try to make.
i try to go with the vertex parent and look how i manage !

Common parent.

Give the curve and the hooks a common parent. Move the curve, and hence hooks relative to parent,  by moving the parent.

This is possible, but unpractical.
You can do this with a Hook and a Vertex Parent, but it will create a position dependency loop, vertex position depends on the position of an object, and the object depends on the position of that vertex, this creates a logic loop, and becomes unstable rendering it unusable.
Select an object, ⇧ Shift Select the desired curve, ↹ Tab into Edit Mode and press Ctrl +  P > Vertex Parent.
This will create a relation between object position and a vertex.
Then still in Edit Mode with the vertex selected go to the menu Control Points > Hook > Hook to Selected Objects. This will link vertex position to the selected object.

You will now see that when you move the vertex in Edit Mode the object will move as well, and vice versa, but the movement will be increased exponentially, because blender is trying to keep both in sync simultaneously.
This will lead to hard to control results that are most likely not what you expect. A better solution is to stick to only one type on linkage, either just Hooks and manually update Edit Mode geometry positions, or stick with vertex parents, and refrain from editing in Object Mode.

Wow. I'm amazed the dependency graph lets you get away with this.

Wonder if this is even possible to solve elegantly


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making a bending object
What kind of methods are there to make object behave like it would be a spring , a metallic object
that bends just a little when you move it around, or like a piece of metal string .?,
that bends just a little when you move it around ( with a added hook )
when trying cloth simulator or softbody i can´t get it to come inflexible inaf.

Rig your string with two bones at each end. Paint the Weight of how you want your spring to behave. For example: Heavy bending in the middle -> Red middle area to blue outter area.
then pin one bone to the hook.
Hope it helps. "weight paint" is the phrase you should look for

Hi, thanks for the post.  It sounds like this is the solution.  If you can, please add screenshots of the steps and expand on the process wherever possible.


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Eevee - how to do god rays emitting from a transparent object?
Alright, Im trying to emulate the god rays/light streaks emitted from an explosion like this, in 2.8 eevee -

Ive looked at typical tutorials like https://www.youtube.com/watch?v=MQooOGayOQI and https://www.youtube.com/watch?v=N8wLd4Lob-o but these all deal with opaque objects to filter the light source.
I have a series of transparent bubbles that comprise my explosion - upping the intensity on a point light does nothing for this.
How can I accomplish god rays out of an explosion?

I know this also involves the use of opacity to obscure the light, but unfortunately, that is one of the limitations of EEVEE. You can't apply masks directly to lights using nodes like in Cycles. However one way you could do this is to give the sphere itself a semi transparent texture, and then shine a light through it, capturing the rays with a volume.
Start with a sphere and give it a texture with transparent "holes". I used a Noise Texture, clamped with a ColorRamp to make this texture, and since it's black and white, I also used it as an alpha factor. As you can see on the right, I set the Blend Mode to Alpha-Clip.

Next, add a cube, roughly the size of the desired "explosive radius", and give it a volume with a Volume Scatter node. You may want to adjust the density to meet your needs.

Then, just place a point light at the center of the sphere. You can make the "god rays" look cleaner and more defined by adjusting the Volumetrics settings in the Render Properties panel. You can change the color of the light as needed. However, there are some limitations to the volumetrics in EEVEE - as you can see, the rays hit the edge of the cube in a rather noticeable fashion. You can make the cube bigger, but then the volume density can become more noticeable. You may have to spend time adjusting things until it looks tight in your scene.


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PSD image texture - material not updating?
I need a way to LIVE draw shapes on my objects in blender, meaning creating squares, circles, etc as one would in Photoshop but in Blender so I can see how it looks.
So far Id just done this creating objects and making them flat -

but this isn't ideal. Next to keep the live updating I tried selecting a PSD as my material texture and UV unwrapping like this, but the PSD doesn't update live. Have to close out blender for a new shape to appear even saving the PSD file -

I need a way to add shape images/draw on my materials - how can I do this correctly? The paint tool in  Blender doesn't seem to allow for clean shapes like PS.

Create your shapes as black and white images in rgb, or with alpha, and use the Stencil tool to paint the shapes into the texture in the 3d view.
You can get clean shapes only if your target image is high enough in resolution as well as the stencil image being high enough in resolution - balance is necessary or otherwise you get pixelation from too low of resolution of what you are painting through or what you are painting onto.
Using the Stencil image as a Brush Mask texture, you can move it aroudn the viewport with Alt-RMB and scale with Shift-Alt-RMB, and rotate with Ctrl-Alt-RMB.
I compose shapes for use as brushes from a separate scene using an orthographic camera looking down, and I use shadeless material objects like high resolution curves and mesh objects, rendering the world as transparent. It is also the best way I have found to make stencils, and I sometimes use them as Brush textures and use Procedural textures as Brush Mask textures to chip away at the stencil I am painting.