What are the differences between proxying and parenting in ManuelLab?

In ManuelLab, you may Proxy items to the mesh before Finalization. This means it will share the same origin point as the body, and when you pose the body and fit the proxy ater calibration, it will match the pose by location.

I am raising this topic because, time and time again, I have tried proxying clothes to the mesh, and while it worked and did exactly what it was supposed to, the sleeves also twisted with the arms, which is unnatural with clothes.

Parenting is much the same as proxying, only it moves as the skeleton does, not after fitting the proxy. They are quite similar, yes. However, when trying to do this with cloth meshes, use the play button to run a simulation (make sure to raise the frame count) and avoid proxying. This is especially meaningful for long-sleeved clothes. Short-sleeved clothes will be mostly fine.

This is no attempt to defame proxying (or even parenting), as I have found it plenty useful, but I have learned to keep in mind how cloth meshes will look, even to my absent-minded dismay, when proxying and expecting the ends to not twist around.
At this time, I am not sure if proxying works with motion capture, but I wager it would be plenty fantasic and useful if it does.


3D Printing Thickness and Thin Faces Problem

Thin faces are not that the object is thin. A thin face is that you have two faces that are occupying almost exactly the same space. Somewhere you have created  for instance  a  face between four vertices  and then created a face  between three  of those  faces. The two faces occupy the same  space.
The distance between faces can be set in the 3d printing tool.


What sculpting tools would I use to separate a jaw from the skull?

There is the Boolean Modifier in Blender. It's can be used to separate, merge, and cut off parts of objects/meshes. In your case, you can easily cut the lips and create an oral cavity with it. Then use the Pose brush to open the mouth.
Separate the lips
First, create a "knife". For this, switch to Object Mode (CTRL + TAB). Add a plane (SHIFT + A). Add a Solidify modifier to add some thickness. (The modifiers are located on the right side. Click the blue wrench icon.) Add the Solidify modifier, adjust the Thickness, then apply the modifier (in Blender 2.9, you need to press the little arrow on the right side of the modifier's name). Then scale and rotate the "knife" so you can place it between the lips of your dino head. Use S to scale. While scaling you can (for example) press X to restrict the scale to the X-axis. Use R to rotate, and G to move it around.

Now cut the lips apart. To do so, place the "kife" right at the beginning of the dino's lips between them where you want to separate them. Select the dino's head. Add the Boolean modifier to the head. In the modifier's options select the plane ("knife") as Object value, use the default mode Difference to cut out geometry. Apply the modifier. After that, move the knife a bit further along the lips into the head, apply again a Boolean modifier. Repeat these steps again if needed until you have cut the full length of the lips.

Create the oral cavity
This is very easy to do. Still in Object Mode, just add a sphere, scale it and place the dino's head where the cavity should be. Then select the head, and apply a Boolean modifier with the sphere as Object value and mode Difference.
Open the mouth
Switch to Sculpt mode. Use the Mask brush to mask the upper jaw of the head. This prevents that this area is affected by brushes. Then use the Pose brush with big size to move the lower jaw down. This part is a bit tricky since it still can happen that some vertices from the upper jaw are dragged down. Try to hide the masked area or use the Pose brush at a different spot or angle.

In the Sculpt menu you can hide masked areas and reveal them again.
The added geometry (cavity) has a lower vertex count. Switch on Wireframe overlay or to Edit mode to check it. You can use the Remesh in Sculpt Mode, or activate DynTopo and touch the area with the Clay brush and a very low strength to add needed geometry when you want to sculpt details there.


2.90 "keyword "apply_as" unrecognized" - Error

This is not specific to boolean modifier. There was changes to python for modifiers. Remove the apply_as='DATA' and it should work.
Before we did
for data
bpy.ops.object.modifier_apply(apply_as='DATA')

for shapekey
bpy.ops.object.modifier_apply(apply_as='SHAPE')

Now we do
for data
bpy.ops.object.modifier_apply()

for apply shapekey
bpy.ops.object.modifier_apply_as_shapekey(keep_modifier=False)

for save shapekey
bpy.ops.object.modifier_apply_as_shapekey(keep_modifier=True)

To use multiple versions of Blender, you can do like this.
version = bpy.app.version

if version >= (2, 91, 0):
    bpy.ops.object.modifier_apply()
else;
    bpy.ops.object.modifier_apply(apply_as='DATA')


How to prevent Blender to overheat my computer while rendering?

For complex rendering in general, reducing the "threads" can help. (Under performance tab in render)
The computer will auto-calculate it, but you can set it lower than the auto value through the "fixed" option. The render will be slower, but it will be less intense and cause less heating/crashes.


You could use the Bevel Modifier from the properties panel.

Example with Segments set to 3 and Width 0.1 (red cube) Width 0.3 (blue cube)


Can I vertex paint on top of procedural texture?

Most definitely you can mix your vertex paint and your texture paint together in your material node tree and preview the result - here is Suzanne with some default Dirty Vertex Paint and a flat brown image texture slot mixed with a color mix node set to 'Overlay'  - left window is the vertex dirt, right window is the combined shading result.


Well, you are not only bevelling the two circular edge rings, you are bevelling every edge between them.

That can for example happen when one uses Vertex Select Mode. When selecting vertices, every edge between them is automatically selected, too. That's why it's not possible to extrude a checker pattern in one go.

Use Edge Select Mode and only select the two edge rings, for example with ALT right click. Then you will get a nice and clean bevel. Make sure your object isn't scaled. That can distort the bevel as well.


how do I get ATI Radeon HD 5800 Series graphics to work with blender?

EDIT I thought I'd fixed my issue but if you see the next EDIT after this remark I was mistaken

Okay I fixed my issue... I needed to remove all traces of the old drivers...

Then reinstall them by going to the AMD website and downloading the auto-detect utility and running it.

I read it very carefully and before installing the graphics card drivers, there is a note at the top of the app stating that it don't install chipset drivers so I did that first and was prompted to restart the machine.

I Then relocated the auto-detect utility and proceeded to install the graphics drivers followed by the APU drivers (found on AMD.com) also.

Everything seems to be working nicely now and I have a new option in the user preferences;

I am now rendering a complex scene and see notable improvements in speed!

EDIT:

It seems that support at this stage is only partial for lower grade AMD graphics cards... namely only GCN cards are supported and blender will hang if you change to cycles and change the setting from CPU to GPU Compute in the render tab.

Its rather convoluted and this behaviour should be blocked! I reported it as a bug but the devs are very busy and seem to think its a report and not a bug so we will have to put up with it until they discover it and fix it themselves.

This seems unlikely to happen because they all use powerful computers, so the message here is get better hardware because they don't care about bugs that effect older hardware...

lesson to be learnt... If you don't have the means, you won't discover that till you waste your time after not having any way of knowing it (unless your omniscient).

Lets just hope that they include support for older architecture graphics cards in the future because older graphics cards still have quite a lot of raw processing power and would increase confidence for disgruntled users like me that feel they don't have a voice!


Finding objects from spesific vector from another object location with python?

I would not use the 3D world at all. This is just to make it look nice. I suggest follow the MVC (model-view controller) pattern where the model is in Python.

Model

E.g. the board as 2d-array (list of lists) of fields. Each field knows what figure is on it (or if it is empty).

Any operation will be performed on that board (moving figures, removing figures etc.). The chess rules will be applied on that operations.

View

The view is what the user sees. So this is the 3D world. With all the meshes and materials. Whenever the model changes ... the view (3D world) will be updated. You can add eye-candy animations wherever you want. It has no impact on the model as it is not important to the chess game itself.

Important is that the model notifies the view when something changed. So the 3D objects know they need to do something.

Example A: the King moved from A1 to B2 (model change). You notify the view that there was a change.

The King sees: "I'm relocated to B2" -> so he jumps, crouches, flies .... to the location associated with B2.

Example B the King moved from A1 to B2 and tower (at B2) gets removed.

The King sees: "I'm relocated to B2 hitting the tower" -> so he fights .... to the location associated with B2.
The Tower sees: "I'm need to disappear" -> hie fights with the King and disappears with an explosion.

I hope you get the idea. (If not imagine your display is a 8x8 block of ascii characters). The model should still be able to do chess.

Controller

How does the model know what operation to perform? Here you need the controller (not to confuse with the BGE logic brick controller). The controller notifies the model about any input from the view (or somewhere else).

Example A

When the user clicks on the king the controller tells the model the user selected the king. The model calculates what fields are available for moving the king (the model knows the rules!). Then it notifies the view that there is an update (selection changed, clickable fields changed). The view shows a nice representation (e.g highlight the King, let the available fields glow).

When the user clicks on a available field (B2), the controller tells the model that this field was selected. The model moves the King to B2 ... see example A of section view.

Example B

When the user clicks on the king the controller tells the model the user selected the king. The model calculates what fields are available for moving the king (the model knows the rules!). Then it notifies the view that there is an update (selection changed, clickable fields changed). The view shows a nice representation (e.g highlight the King, let the available fields glow). As B2 is occupied by the tower, the tower gets an highlight too.

When the user clicks on the tower/field (B2), the controller tells the model that this field was selected. The model validates if that was a valid move removes the tower and moves the King to B2  ... see example B of section view.

Conclusion:

The MVC pattern, let you isolate the core game logic (chess rules, board data, chess operations) from pure visual aspects and user input.

The model should be independent -> the model should not know about the view or the controller. It should just know there is a view and how to tell that it should update (e.g. communication via messages).

Keep in mind the model could use any view and controller such as text output and calculated turns (from a chess engine/AI) in any combination. There can be even several of them at the same time.

The model defines an interface for communication to the view and from/to the controller.

I do not think that there is a sufficient way to implement a chess model without Python in the BGE.


This yellow line represents some type of baked movement like rigidbody , or a constraint , to have a look if this is the problem , you can click on the Physics properties tab 2nd block from the modifiers , their if you see a rigidbody constraint , you need to click the cross to remove it and then start your timeline from the first frame .


You most likely have "X" Symmetry enabled in the tools panel if you are experiencing this issue while texture painting in Blender.


Maybe you can try to use the "Decimate" modifier.
It will try to reduce the number of poly but keeping the global geometry of your mesh.
You can also search for some retopology workflow, or some addon.
And last, you can try to use some other tool for Blender like Instant Mesh
https://github.com/wjakob/instant-meshes


Possible Python Automation With This Particular Material

I would use two UV maps for each key. One is shared between all keys and maps to the key texture without letter. The second is a different UV map for each object, with one big texture containing all the key letters; having a different UV map for each key, each gets their own letter. No need to worry about the material itself then.

You can even use the UV Project modifier to project the letters on each object; no need to manually make all those UV maps.


Particles tab is not available when I use nurbs path

You need to have a mesh object as the emitting object selected.

Currently you have a curve selected, and curves can't have a particle system.

Select a mesh object as the emitter, or convert your curve to a mesh (AltC)


Where is the Name option in dynamic paint canvas v 2.79

Mouse click twice on default Surface name to enter rename-function.


Please go through this video for the types of modeling

https://www.youtube.com/watch?v=y-CvkAm9CYA

To start straight away with character Darenlile video is a good source

https://www.youtube.com/watch?v=0QT1GNMevfc


As you already discovered an object can be placed into any arbitrary number of collections, even on different scenes.
Moving or linking an object is really the same underlying action in relation to collection ownership. There is no "real" and "instanced" duplicate of an object that belongs to more than one collection, and the object truly is in multiple simultaneously with the same degree of importance.
So what is the different between "Linking" and "Moving" to a collection? If an object is moved to a collection it is removed from all others and placed in that one exclusively.
Say you have a car in your scene currently sitting in the Street collection, and you Move it to the Vehicles collection. Your car will now sit exclusively in the Vehicles collection.
Linking an object to a collections adds it to that collection without removing it from any others it curreclty sits in.
Using the same car example, if you have a car in your scene currently sitting in the Street collection, and you Link it to the Vehicles collection, your car will now sit both in the Vehicles collection and the Street. Both instances are real both are valid.
So why can you Unlink an object that has been moved to a collection? Likewise unlinking an object from a collection will remove it from that collection but not from others.
If the object is only in a single collection and you unlink it, it is removed from the current scene. If the same object is not used in any other scene it becomes Orphaned Data and can be purged out of the current file.


The new "absolute" snapping mode in 2.76 should do the trick. Press n, look in Display, set the grid scale to what you need, and it'll snap to wherever the grid is.

Hope that helps!

http://oneminutevideotutorials.com/absolute-grid-snapping-in-blender-2-76/


Alembic sequence only renders the first frame

unfortunately, this is a known issue in the alembic importer for Blender. I hope they will fix this soon. source: https://developer.blender.org/T58704


I forgot to post my answer oops, but Leander has cleared things up for me. Basically i cant mirror a bone axis exactly and this bone roll behavior is normal
and during animation i have to set certain roll modes depending on what the bone is actually suppose to accomplish. Quaternion is better along bones with a vertical axis while horizontal seems to prefer regular xyz Euler coordinates. This allows me to mirror my pose correctly.


Why not use a simple plane with some modifiers? I have added a Subdivision + Wave modifier, then added a Solidify modifier to give it thickness.

Then I changed the camera to Orthographic to shoot only the wave part.


Looks like the normals on the mesh are wrong/inverted. UV mapping has to be resized and offset completely for the texture to show up and Unwrapping shows an "warning" message. I suggest to rework your mesh and generate a clean UV Map.


The big wrinkles should be sculpted and the small ones should be painted after the retopology and after baking the normals.
If your model is meant to be rendered within Blender, you can restore lost detail on the retopologized model by adding a multiresolution modifier and a shrinkwrap modifier that you apply (only the shrinkwrap). Note that you have to apply it while the shrinkwrap is below the multires, otherwise it doesn't work.

Painting on a triangle mesh is a bad idea.


How to install Blender on a Intel Core i5 with Windows 7?

All you need is to go to the Blender.org website and there should be a big "Download" with the name of the most recent version. Just click that and it will take you to a download page where you select your operating system. If it doesn't ask it might detect what you have already. You most likely have 32 bit so if it asks for "16 bit or 32 bit" choose the 32 option. If that doesn't run you could try downloading the other version later. After you hit the big download button, it should proceed to download. If you are using Chrome or most causal web browsers you should be able to see it in progress on the bottom of your screen. When it is done you can select it.
The installer will show up and then you can just keep hitting "next" until you finish the installer. You should make sure the "Add shortcut to desktop" is checked. Then you can start it by starting the shortcut that is now on your desktop.
Your computer should be able to run Blender just fine. However, you might start seeing some lag if you start making anything too complex. If you are just starting out make simple things and if you want to make a lot of objects use different files instead of having everything in the same file. This will make sure Blender is only using the memory that you want it to.


i posted exactly how to do this in your other post almost a month ago.

Can I use Weight Paint to Control Animation Properties?

The following code will work on an object i fractured using  Cell fracture, the object named "Cube". then i used the Bullet Constraint tools 'Single constraint' to make the constraints.
this code wont work if you have used Empties to constrain the objects together.

and a blend file.

https://dl.dropboxusercontent.com/u/14364171/constraint_control.blend

press alt A, you will see the box stays together.
run the script (alt P in textblock) and then animate again. you will see the box stays together, until the plane moves above each object.

object_name = "Cube"

import bpy

for obj in bpy.data.objects:
    if  object_name+"_cell" in obj.name:
        driver = obj.rigid_body_constraint.driver_add('enabled')
        driver.driver.expression="this_obj<mask_obj"
        driver_variable = driver.driver.variables.new()
        driver_variable.name = "this_obj"
        driver_variable.type = 'TRANSFORMS'
        driver_variable.targets[0].transform_type = 'LOC_Z'
        driver_variable.targets[0].id = driver_variable.id_data

        driver_variable = driver.driver.variables.new()
        driver_variable.name = "mask_obj"
        driver_variable.type = 'TRANSFORMS'
        driver_variable.targets[0].transform_type = 'LOC_Z'
        driver_variable.targets[0].id = bpy.data.objects['mask']


How to add a Texture to a Material using Python?

Similar to material_slot.material, there is a texture_slot.texture

(I'm assuming Blender internal from the texture_slots.add in q)

mat = bpy.data.materials['Material']
tex = bpy.data.textures.new("SomeName", 'IMAGE')
slot = mat.texture_slots.add()
slot.texture = tex

A simple example using Cycles can be found here https://blender.stackexchange.com/a/14115/15543


You probably opened the scene world and here is how to close it: at the top right you have 3 viewports and at the right of them, there is an arrow points down, click it and there should be scene lights and scene worlds. You need to close all of them. If your problem something like I think, that will solve it.
And btw you need to add lights to show colours on rendering.


I can't see through the reference image in wireframe

You mean see the reference image through the objects in your scene? If that is the case one option would be to press "Shift-Z" in order to see the scene transparent. There is of course a button as well for it next to the wireframe button. in the picture below I have both wireframe mode and show x ray selected


How to save settings before a factory reset?

By clicking the + next to the theme name you can save your current settings for your own theme. You can then select your theme after you choose factory default settings.

A gotcha with this is that the theme gets saved inside the blender installed files, so can be overwritten or deleted as blender is updated. To keep your theme for future versions you should find the saved file and move it into your configuration folder. Within the files installed for blender you will find your theme inside 2.75/scripts/presets/interface_theme (adjust 2.75 to match your current blender version). Locate your blender configuration folder and create a matching path and move your theme there. On a *nix system that would be $HOME/.config/blender/2.75/scripts/presets/interface_theme/MyTheme.xml


How to obtain the parent of a collection using Python

The best I could come up with so far is a recursion that searches for the parent collection. Note that this is not a particularly efficient solution but at least it solves my problem. The code looks as follows:

import bpy

def get_parent_collection_names(collection, parent_names):
  for parent_collection in bpy.data.collections:
    if collection.name in parent_collection.children.keys():
      parent_names.append(parent_collection.name)
      get_parent_collection_names(parent_collection, parent_names)
      return

def turn_collection_hierarchy_into_path(obj):
  parent_collection = obj.users_collection[0]
  parent_names      = []
  parent_names.append(parent_collection.name)
  get_parent_collection_names(parent_collection, parent_names)
  parent_names.reverse()
  return '\\'.join(parent_names)

obj = bpy.context.view_layer.objects.active
print(turn_collection_hierarchy_into_path(obj))

This code will print out the collection hierarchy of the selected object as a Windows style path (backslash as separator).

Note that objects can be part of multiple collections which means you can actually create a graph, not just a tree. The above code will simply ignore that fact and just pick the first collection that the object is part of.


Is there an efficient way to scale UVs on many objects at once?

Well, I puttered around in the python console and bashed this script together:

import bpy
for mesh in bpy.data.meshes:
    changed = 0
    usedverts = set()
    for face in mesh.polygons:
        for layer, texmap in enumerate(mesh.uv_textures):
            tex = texmap.data[face.index]
            if tex.image and tex.image.name == 'construction-facemelt.tga':
                for v in face.loop_indices:
                    if v not in usedverts:
                        uv = mesh.uv_layers[layer].data[v].uv
                        uv.y = uv.y / 2.0 + 0.5
                        changed += 1
                        usedverts.add(v)

    if changed > 0:
        print("Updated", changed, "UVs on", mesh.name)

I mostly put this together via console introspection and guesswork, so, there might be a lot of ways to do it better; I still barely understand the python blender api. But it works, and the bits to customize to make it work for another situation should be self-evident...


That looks the Sintel rig from Blender Foundation Open Movie Durian Project  Sintel.

It is open content freely available to anyone, you can use it study it, modify it and redistribute it as you see fit, along with all assets and production files from the movie.

You can access it by subscribing to the Blender Cloud just like any of the content from all other Blender Foundation Open Projects which will cost you a small symbolic monthly fee.

While doing so you will also be happy to know you are helping the Blender foundation monetarily, and funding Blender development that benefits everyone.


This looks more like an object than a reflection to me, my guess without seeing your file is that you have an object hidden in viewport yet set to visible in the render.


The problem is most likely caused by the fact your vertices don't align well on the plane of the quad. And the render engine doesn't magically create new data and uses the quad as is ( which is basically just 2 triangles anyways ). If you look at the lower vertex of the quad you can see it's pointing a bit inwards. If you were to divide a quad into 2 triangles you'd see an edge going trough the middle and that's exactly what happens here.

You might want to consider adding more faces to accommodate for slope or change your shape a bit to make the quads vertices more aligned. Or use smooth shading and the normals of the face are interpolated to bend between faces.

Technically @Ween 's answers should work as it aligns the vertices to be on the same plane preventing the triangle bend of the quad.


If you are getting this problem in only one project, I suggest creating a new file, and appending all of the objects, materials, actions, etc in the existing project, then, if you get the result you want, save over the project.


Subdividing Bezier curves is normally done using De Casteljau's algorithm.  However, fcurves aren't pure Bezier curves.  It is not hard to make a bezier curve "run backwards" along the time axis.  Since this would create ambiguities in the animation system, blender prevents that by using modified handle coordinates whenever the handles could make the curve backtrack in the time axis.  Once we understand that math, we have what is needed to properly subdivide the fcurve.

Here is an excerpt from http://web.purplefrog.com/~thoth/blender/python-cookbook/subdivide-fcurve.html which demonstrates the technique:

def correct_bezpart(p):
    if p[1].x <= p[2].x:
        return p

    scale = (p[3].x - p[0].x) / ( (p[1].x - p[0].x) + (p[3].x - p[2].x) )

    p = list(p)

    p[1] = p[0] + scale * (p[1]-p[0])
    p[2] = p[3] + scale * (p[2]-p[3])

    return p

def interp(v0, t, v1):
    return (1-t)*v0 + t*v1

def de_casteljeu( p , t):
    q = [0,0,0,0]
    r = [0,0,0,0]

    q[0] = p[0]
    r[3] = p[3]

    q[1] = interp(p[0], t, p[1])
    x    = interp(p[1], t, p[2])
    r[2] = interp(p[2], t, p[3])

    #print([ r[2], '= interp(', p[2], t, p[3], ")" ])

    q[2] = interp(q[1], t, x)
    r[1] = interp(x, t, r[2])

    q[3] = r[0] = interp(q[2], t, r[1])

    return (q,r)

def subdivide_fcurve(fc, frame):

    orig_keyframe_count = len(fc.keyframe_points)

    fc.keyframe_points.add(1) # do this before we have any keyframe_points[i] references that would be invalidated
    kp9 = fc.keyframe_points[orig_keyframe_count]

    for i in range(1, orig_keyframe_count):
        kp0 = fc.keyframe_points[i-1]
        kp1 = fc.keyframe_points[i]
        if (kp1.co.x >=frame):
            break

    p = (kp0.co, kp0.handle_right, kp1.handle_left, kp1.co)
    p = correct_bezpart(p)

    t = tForFrame(frame, p[0].x, p[1].x, p[2].x, p[3].x)

    q,r = de_casteljeu(p,t)

    kp0.handle_right_type='FREE'
    kp9.handle_left_type='FREE'
    kp9.handle_right_type='FREE'
    kp1.handle_left_type='FREE'

    kp0.handle_right = q[1]
    kp9.handle_left = q[2]
    kp9.co = q[3]
    kp9.handle_right = r[1]
    kp1.handle_left = r[2]

    fc.update()

#

def bez_root_score(t):
    return max(abs(t.imag), 0-t.real, t.real-1)

def favorite_root(roots):
    """ Since we are confident that at least one of the roots is real, pick the one that has the imaginary component closest to zero
    """
    fav = roots[0]
    score = bez_root_score(fav)

    for i in range(1, len(roots)):
        if bez_root_score(roots[i]) < score:
            fav = roots[i]
            score = bez_root_score(roots[i])
    return fav

def tForFrame(fr, p0, p1, p2, p3):
    """
    fr = (1-t)**3 *p0 + 3*(1-t)**2 *t *p1 + 3*(1-t)* t**2 * p2 + t**3 *p3
    """

    import numpy

    coefficients = [
        -p0+3*p1-3*p2+p3,
        3*p0-6*p1+3*p2,
        -3*p0+3*p1,
        p0-fr
    ]

    roots = numpy.roots(coefficients)
    #print(roots)

    rval = favorite_root(roots).real

    sanity = bez(rval, p0,p1,p2,p3)
    if abs(sanity-fr) >1e-6:
        print(["defective", sanity, fr])
        print(roots)
        print([rval, "for", fr, p0, p1,p2,p3])

    if rval<0 or rval>1:
        print(["wiggy, bez(",rval,p0, p1,p2,p3,") = ",fr])
        print(roots)
        print([rval, "for", fr, p0, p1,p2,p3])
    return rval

def bez(t, p0, p1, p2, p3):
    s = 1-t

    return s*s*s*p0 + 3*s*s*t*p1 + 3*s*t*t*p2 + t*t*t*p3

def mission2(obj):
    create_sample_fcurve(obj)

    subdivide_fcurve(obj.animation_data.action.fcurves[1], 33)

#
#

random.seed=4262

mission2(bpy.context.active_object)


Windows's Blender preferences, scripts, and themes are located at:

C:\Users\<your username>\AppData\Roaming\Blender Foundation\Blender\<version number: ex. 2.78>\

The theme folder is located at:

C:\Users\<your username>\AppData\Roaming\Blender Foundation\Blender\<version number: ex. 2.78>\scripts\presets\interface_theme

For example,

C:\Users\user1\AppData\Roaming\Blender Foundation\Blender\2.78\scripts\presets\interface_theme


Is there a way to navigate the file system more efficiently in Blender?

If you know the path you want, You can copy and paste it into the address bar. That'll take you straight to where you want to go!

For me, I keep all of my related files local to the blender file, as if the blender file is a main project.


Maybe you need to switch from Blender Render to Cycles Render


This is commonly because you installed Blender as one user (administrator) and are running it as a different user.

From http://blenderartists.org/forum/showthread.php?196976-My-Blender-2-5-Interface-is-Mostly-Empty

  Happens when you run Blender as a different user as who installed it (Windows).
  Reason: The blender folder in User-Folder / Appdata /Roaming is required but only there for the user who installed it
  Workaround: Always run Blender as the primary user (Run as Administrator) or: Copy the Blender Foundation folder from Appdata/Roaming of the primary user to your account's folder.

So, Blender doesn't have access to some of the folders it needs because they are on another user's account. This could also apply to some Python scripts. If Python was installed by another user, you might not have access to it on your account.

Hope that helps!


Positioning unconnected bones in pose mode using cursor

All your bones need to be positioned correctly in Edit mode. In Edit mode you will build the basic/rest pose of the character. All the changes you will make in Pose mode are only for animations purpose (or to create static particular poses) and won't affect the bone positions in Edit mode. So if the bone aligned to an object is supposed to be the rest pose, you have to do it in Edit mode, if this is supposed to be an animation pose, do it in Pose mode.


Nodes not visible for material created in properties panel

Here are some possible causes:

You're working in blender internal rather than cycles:
You're working with the compositing nodes:
Make sure that the selected option is the little ball, not the one that's selected in the image.
Your view is not in the right place. hit the . key on your number pad. if nothing happens, hit A then ..
Make sure use nodes is checked


How to evenly space vertices along several segments bezier curve

As far as I know there is currently no way to do what you ask in Blender.

There currently is no tool to evenly place existing vertex long a curve.

If you already have a curve with the desired shape and wish to add additional vertex you can use the Subdivide operator under the Specials Menu W key. This will evenly subdivide currently selected segments and place vertex along its length at regular intervals while trying to maintain the shape as best as possible.

One workaround you might use is using an array modifier on a mesh to reconstruct you curve.

Create a new mesh
Erase everything but one single edge
Place one of it's vertex on the object's origin so that the edge starts at local coordinates 0,0,0 and extends horizontally in X
Align that object with your curve (same object coordinates and same rotation)
Add an array modifier to the new mesh and set it to Fit Curve mode
Pick your curve as length object and turn on option Merge in the array modifier
Now add a Curve Modifier to the mesh and set it to use your same curve
You should now have a mesh with the same shape as your curve and evenly spaced vertex.
Adjust your mesh edge length to fit your desired level of detail or vertex spacing
Convert your mesh to a curve with Alt+C > Curve from mesh
Enter edit mode on newly created curve and set it's type to Bezier (Tool Shelf > Tools > Set Spline Type button)
Set it's handle types to Auto for smoothest results with the V menu Set handle type > Automatic

Hope this helps


Check out the loop tool plugin, it comes along the with blender.

Just enable and have a try. You seem to have used lot of subdivision, which makes the task a little difficult.


Why do some values on nodes lack an input socket?

The reason is that this is the way the node is written by the developer,
Sometimes it makes sense for values to be adjusted per-pixel and sockets are used, other times its enough to have a setting on the node.

The are undoubtedly cases where you might want to adjust a setting per-pixel but there isn't a socket input. I guess you could call this a not-yet-implemented feature. There may be a good reason the developer chose not to do this, or it may be an oversight.


How to do a cloth simulation in Blender?

First of all you need to create two geometry first are UV sphere and plane. Use shift+a to add a mesh. Now select the plane mesh and go to edit mode (press tab) select all (press a) then press w to call special menu and select subdivide. I prefer to increase the number of cuts to 10 (more are better but slower).

After this you can optionally add modifier subsurf and turn on shading smooth, for better look of the cloth.

Next, go back to object mode and with the plane still selected, navigate to physic tab in the property panel. Select cloth in the first column, third row.

Then select the UV sphere and directly navigate to physic tab again and select collision in the first column, second row.

Now you can start play the animation by pressing alt+a or the play button in timeline. The cloth sims now should start.


what's the precise name of command, 'shift + r'?

The option is 'Repeat Last'. You can view and edit the shortcuts in the 'Input' section of the Blender Preferences.


How to do vaccuum sealed pack modeling in Blender?

I'm adding another answer because things have changed with Blender 2.82 (which is still in alpha and can be downloaded here). Namely, you can now use pressure inside cloth volumes, including negative pressure.

This makes it much easier to simulate a vacuum sealed pack accurately:

Enable Physics > Collision on your target objects
Model a mesh representing the "relaxed" bag around your objects; give it a good level of subdivision

Select the vertices along the rim, and assign them to a vertex group with a weight of 0.6 - 0.7.

Another option is to only select one, or three, edges of the rim, to simulate different kinds of bags/vacuum apparatus.

We use this to quickly create a "stiffer" rim. There are however better ways of doing this (like fine-tuning the structural springs parameters instead of the pin groups).
Enable Physics > Cloth on your bag.

Parameters: I've mostly used the defaults, but

the Quality Steps must be higher, around 25
under Shape > Pin group, select the vertex group you created at step 3
under Collision, increase the Quality to around 8, and enable Self collisions
under Field Weights, remove (set as zero) the influence of Gravity

Lastly, select a value around -100 for Cloth > Pressure (in my example I've done it more gradually, going from 0 to -100 over 40 frames, but it turned out to be unnecessary)
Decrease the Cache length to around 40 frames, then Bake

You can now go to the last frame and "Apply" the Cloth Modifier (if you want to get rid of the simulation)


Where is the definition of this function "layout.template_node_view"

It's defined in C code here: rna_ui_api.c#871

And this is called: node_templates.c#721

I don't know how to use it properly, but I guess you need to roll your own panel for your custom nodes in a custom node tree. This seems to work as panel draw code:

    def draw(self, context):
        layout = self.layout

        ntree = bpy.data.node_groups["NodeTree"] # our custom node tree
        node = ntree.nodes.active # selected node
        for socket in node.outputs:
            layout.template_node_view(ntree, node, socket)


Looks like you're using Blender Internal. Denoising is only available with Cycles Render.

You can change the render engine in the info header at the top of the window:


Instance list of object in animation nodes

It is possible with some trickery.

At first you have to create multiple instances using the same source object in one Object Instancer node. Then you can use the Copy Object Data node to copy the object data (e.g. the mesh) from one object to another.

I activated "Use 'Instance' as Output" so that the 'Instance List' also becomes an output of the Invoke Subprogram node.


If your drawers are separate objects in reality, there are no reason not to make separate meshes in 3D, especially if you want to make some close shots of the desk. Also, you need to keep quads as much as possible, meaning surfaces that have 4 vertices and not 5 or more. For example let's take one of your drawer:

Make it a separate mesh (I've deleted the rest of the object to make it simpler).
It looks like you have a lot of overlaying vertices, so to clean all this press W > Remove Doubles. On the top of the 3D view the amount of deleted vertices will be displayed.
Delete useless vertices with X > Dissolve Vertices.
Also delete vertices that are not part of any face with X > Delete Vertices.
To make quads, use the knife, K to activate, C to cut orthogonally.
Once you have only quads, extrude the whole surface with E.
If the normals are flipped, press ctrlN.
Now you have the facade of one drawer.
You can add depth with some edge loops ctrlR and extrudes E.
Etc...


Environment texture:

First of all you'll need some Environment Map. I suggest to use HDRI imitating photo studio setup. You can find many of them, even for free.

After selecting one change Strenght accordingly to your needs. And you can see our environment.

Background:

To get gray background, or any other color create plane and extrude it with nice subtle curve.

Material:

I'm using simple Diffuse/Glossy mixed by Fresnel but you can go with any other setup. Remember that default color in Blender isn't pure white.

Blend file:

Here it's my blend file with HDRI map packed.


How would I go about making these seem more like planets?

For the Internal renderer:

Add a direction light and give your sphere a new material. Turn the Specular -> Intensity down to 0.

And add your texture. Result:

For the Cycles renderer:

Add a directional light. And give the material a diffuse shader like this:

In the Image Texture node you can put your texture. (Don't forget to UV unwrap your spheres)
This is the result without a texture:


How to crop image based on Alpha in Compositor?

Use this node setup:

In the texture node, you open the image you want to use as a mask, then plug the alpha output from that to the scale node's input for X and Y (the scale node's "Coordinate Space" is set to relative), you grab you RenderLayer and shove it in the image input for the sacle node, and finally connect that to the composite node.


How to sort Shape keys by "a to z" in blender 2.8?

I'm no expert in this area, but something along the lines of this script, executed on the current active object, in Object Mode ?

import bpy

ob = bpy.context.object
skeys = ob.data.shape_keys.key_blocks

skey_names = sorted(skeys.keys(), key=lambda v: v.upper())

for name in skey_names:
    idx = skeys.keys().index(name)
    ob.active_shape_key_index = idx
    bpy.ops.object.shape_key_move(type='BOTTOM')

which works, but any edits to improve style are welcome. I can't help thinking I've handled that list in a clunky way.

EDIT in response to @lemon's comment:

The reason I thought this was clunky was that I thought there was no guarantee of the order of keys in a Python dictionary. But 1... that's not true, and 2... I don't think it matters anyway.

skey_names is just an independent alphabetically sorted list of strings; a snapshot of the dict-keys of the  bpy_prop_collection of shape keys. We are assuming the contents of original property-dictionary will not be modified before the loop terminates, but assume nothing about order .

For each of those sorted names, in order ...

... the ordinary Python dictionary call of .index(str) returns its position in the current state of the original property-dictionary, wherever it is ...
.. to be used to set the read/write .active_shape_key_index to make the shape key labeled by it active...
... so the context-sensitive bpy.ops.object.shape_key_move can send it to the bottom of the list, (preserving the order of the other items).

Sending each item to the bottom of the list in alphabetical order results in an alphabetically-sorted list


Import Unity Model and Animations to Blender

I know this is an old post, but if anyone experiences the same issue, it's very easy to fix.

To import fbx:

Go to File > Import > FBX

When importing the fbx make sure to

Select your fbx file
Select armature in Import FBX option Area
Select automatic bones orientation
Select import

If it's not working as expecting, play around the primary and secondary bones options, but usually, if your fbx is working in unity, the automatic option will do it for you.

Good luck, never give up - keep the good work :)


Scripting: How to change objects mode and then revert back to previous mode

I don't know that is this: bpy.ops.object.mode current mode is here: bpy.context.mode

Save current mode:

returnto=False
if(context.mode!='OBJECT'):
    returnto=context.mode

Return to edit mode:

if(returnto):
    bpy.ops.object.mode_set(mode=returnto)

bpy.context.mode


Press tab in the NLA window so that you get access to the keyframes of your strip in the Dopesheet, then tab again to come back to the normal strip behavior.


How to run a script when when baking is finished?

Blender currently supports only callbacks for these events:

frame_change_pre, frame_change_post
render_pre, render_post
render_stats
load_pre, load_post
save_pre, save_post

The simplest thing you could do is invoke the appropriate bake operator by a script (the python call is displayed when the mouse pointer is over the back button).

Create a python script e.g.:

bpy.ops.fluid.bake()

and add the code to play a sound from How to play a sound after script finishes?


How to place automatically a bone/vertex/object or a group of them in the center of the screen and zoom in them

In the User Preferences under the tab Input there are all the categories for the key bindings.

If you expand the 3DView category and then the 3DView(Global) category by clicking on the little arrows/triangles you can scroll down to the end of 3DView(Global)'s entries until you see the button Add New.

If you click on this button a new entry "none" is added. If you expand it, again by clicking on its arrow, there will be a field that also says "none".
In this field you can put the following:

view3d.view_selected

Press return to accept it. On the right the current shortcut is displayed with its default value "A". LeftClick on that so that it says "Press a key" and click the right mouse button. Now you have assigned RightClick to the operator. You can also chose one or several modifier keys with the checkboxes below.

Now if you select something by right clicking on it it should be put in the center of the screen and zoomed in on.
If you like how it works you can go back to your User Preferences and click Save User Settings.


Using displacement maps (or something else) for adding rotational noise effect to mesh?

Here are two ways in which you can accomplish this:

1) Modify the curve's twist

A bezier curve has the often ignored feature twist that you can set per control point to influence the direction in which the boards are pointing. You can set the twist manually in edit mode by selecting a control point and pressing Ctrl+T, but if you want to create the impression of randomness you will need a lot of control points and manually setting the tilt is going to be tedious.

The following Python script assigns a random tilt to each control point of a bezier curve.

import bpy
import random
from math import pi

curve = bpy.data.objects['Circle']
points = curve.data.splines[0].bezier_points

for point in points:
    point.tilt = random.uniform(-pi/16, pi/16)

Adding the array and curve modifiers to the fence element will allow the fence to distort which is maybe useful for a wire-link fence but may cause ugly deformation of the fence poles.

For a fence consisting of disconnected planks, instead of a regular object array I use a plane array with duplifaces according to this or this answer, so the fence boards don't get distorted. I.e. add a plane, with modifiers array and curve, activate duplication in the plane's Object tab in the properties panel and parent a single fence board to the plane.

I guess it might be possible to try to mix these two approaches, i.e. use regular array for the mesh and duplifaces for the poles. As I don't have a wire-link mesh model available, I couldn't test it on one of those. Tests with a fence like above with horizontal bars were nonsatisfying.

2) Place the boards with Animation Nodes

Using the addon Animation Nodes allows you to place fence boards automatically at the desired location with the right orientation.

Here I use Animation Node's Evaluate Spline node to sample a number ob points along the bezier curve – and for each point get the coordinates as well as the tangent at that point. I project the tangent to the XY plane so that the standard orientation is “up” and not normal on the surface. This part is optional for a flat ground, but looks better if you place the fence on a hill.

I feed the coordinates, and the projected tangents into a loop. For each pair I create a random rotation with the Euler Wiggle node. The amplitudes of the wiggle node affect the amount of randomness for each axis.

There would be room for optimization, e.g. as the wiggle Evolution is linear whereas it might be desirable to match the evolution parameter at the start of the curve to the end of the curve, as it's a closed loop.

I combine the three transformations wiggle, rotation according to the tangent, and translation to the correct coordinate.

Back in the main node tree I place copies of the original board, each board with a transformation from the loop.

I also set a random shape key value for each board to get a random board height – similar to the random particle approach when using Dupligroups.


Not in sculpt mode.
Result in python console of changing absolute mode of object to 'SCULPT' followed by toggling mode
>>> bpy.ops.object.mode_set(mode='SCULPT')
{'FINISHED'}

>>> bpy.ops.sculpt.sculptmode_toggle()
{'FINISHED'}

>>> C.mode
'OBJECT'

hence out of context, since bpy.ops.sculpt.* operators require sculpt mode for context.
Remove toggle to remain in sculpt mode or  move to  the last line to toggle.
Tip
Making a poll method for your operator returning false for selected objects that cannot be sculpted will disable button in UI and remove it from context operator search.


Maths — how to create moving waves with Animation Nodes

Theory

The wave equation is a second order partial differential equation, which means solving it can done by numerical integration, perhaps using the simpler Euler's Method. The one dimensional wave equation is as follows:

$$
\frac{\partial^2 u}{\partial t^2} = c^2 \frac{\partial^2 u}{\partial x^2}
$$

Where $u$ is the displacement, $t$ is the time, and $x$ is the position. The partial derivative on the right hand side is the one dimensional Laplacian. So, to compute it, we use the Discrete Laplace Operator. In particular, we can use a one dimensional convolution kernel, the kernel have the structure:

$$
\begin{bmatrix}
1 \\ -2 \\ 1
\end{bmatrix}
$$

Finally, to be able to solve this, we need to define the initial conditions of the system as well as its boundary conditions. That is, we have to define the initial displacement and the initial velocity. Lets assume that at $t=0$ the velocity was zero ($\left.\frac{\partial u}{\partial t}\right\rvert_{t=0} = 0$) and the displacement was zero everywhere except at a subset of the domain where it was a bell shaped curve. As for the boundary conditions, we shall use a Periodic Boundary Condition.

Implementation

First, give the displacement, we compute the discrete laplacian using the kernel outlined above, this is easily done by vectorization as follows:

Next, given the initial velocity, lets compute the velocity after $\delta$ time using Euler's method as follows:

Next, lets compute the displacement given an initial displacement and the velocity using Euler's method:

Next, we make a solver loop that takes the initial velocity and displacement and reassign them at each iteration:

Finally, we define the initial conditions as discussed before and display the simulation as a circular domain, we also enable per frame caching to get real time results:

By running the animation, we get:

Which seems about right. It should be noted that this is not the most physically or mathematically accurate simulation and it is not computationally efficient either, this is just a simplified heuristic implementation to demonstrate the wave equation.


Animation nodes remove duplicate elements from list

You can use this expression: [i for n, i in enumerate(x) if i not in x[:n]]


How to make a super sonic material in cycles?

I would use the principled shader. It also looks like some anistropy is being used but you will have to play with that. Mess around with the anistropic sliders and roughness to get the desired look. It almost looks like your image has hair the same color as skin so its giving it that sheen look.

The 2nd shader is so you can control the fresnel (the lighter yellow part).


Mirrored mesh deforms unexpectedly and becomes uneven when rendered

I'm not sure about this answer, but to me it looks like a calculation approximation problem: if you add a subsurf modifier to the body mesh, even with only 1 step of subsurf, everithing goes allright (then you can apply it, to get a pure mesh). Blender is not intended as CAD and your mesh is very low poly, maybe also adding some loopcuts would resolve your odd behaviour.

Consider that, generally, we use a circle of vertex for shaping the "hole" of eyes.

Hope it's useful.


Why is this Blender matrix multiplication not distributive?

It is distributive if you convert the world matrix to a $3 \times 3$ matrix first or extend the vector by one dimension. The vector needs to have as many elements as the matrix has columns.
>>> x = bpy.data.objects["Camera"].matrix_world.to_3x3() @ (top_verts[1] - top_verts[0])
>>> x
Vector((1.0669403076171875, 1.1318906545639038, 0.0))

>>> y = bpy.data.objects["Camera"].matrix_world.to_3x3() @ top_verts[1] - bpy.data.objects["Camera"].matrix_world.to_3x3() @ top_verts[0]
>>> y
Vector((1.0669403076171875, 1.1318907737731934, 0.0))

Generally it is not possible to multiply a $4 \times 4$ matrix with a $3 \times 1$ vector, because the dimensions don't match. Blender tries to be smart and extends the dimension of the vector by adding elements with value $1.0$ when necessary. However, since this is only done when the multiplication is performed, it is no longer distributive:
$M \times \left(\overrightarrow{v} + \overrightarrow{v}\right)_{extended} \neq M \times \overrightarrow{v_{extended}} + M \times \overrightarrow{v_{extended}}$
The reason for the difference is that Blender can perform the addition $\overrightarrow{v} + \overrightarrow{v}$ without extending the individual vectors. The element is only added afterwards when the multiplications with $M$ is performed. In comparison, $M \times \overrightarrow{v_{extended}} + M \times \overrightarrow{v_{extended}}$ requires to extend both vectors right away. The results are not equal since in the former case the vector should have been extended prior to the addition, resulting in a fourth element of value $2.0$. However, Blender performs the extension afterwards with an element of value $1.0$.
Blender tries to help the developer, perhaps a bit too much in this case, thus masking the error of wrong dimensions. This is especially hard to see since the output is truncated to the size of the original vector.


You have a foreground and a background render layers. The background layer is setup to multiply shadows over the video layer (that's why the butteflies look like... shadows). The foreground is set up as alpha over and it should be the one that combines your scene color information over the background using an alpha channel. The issue is that your foreground layer is empty! You are rendering the contents of an empty layer and using the only layer that contains information as a mask!

Instead of an empty layer, use the layer that contains your scene.


Some vertices stopped moving in sculpt mode

This vertexes are masked. https://wiki.blender.org/index.php/Dev:Ref/Release_Notes/2.64/Sculpting

Masks are used to "protect" parts of the model from being edited by the sculpting tools. They appear as darkened areas of the mesh. The darker a masked area is, the less effect sculpting on it will have. Masks can be edited with the mask brush, as well as cleared or inverted accross the entire model. The masking feature is active as soon as sculpt mode is entered; there is no separate toggle.

To clear mask use Alt+M


How do I register 'Scene' properties with Python in 2.8?

Annotations in 2.80

Not sure of the problem here. 2.8 uses annotations, currently not doing so produces a warning message.

Test code to confirm operation in 2.80

import bpy

class MySettings(bpy.types.PropertyGroup):
    # use an annotation
    lockHead : bpy.props.BoolProperty(
        name="Enable or Disable",
        description="Lock the head position of the bone",
        default=False
        )

def register():
    bpy.utils.register_class(MySettings)
    bpy.types.Scene.my_tool = bpy.props.PointerProperty(type=MySettings)

if __name__ == "__main__":
    register()
    print(bpy.context.scene.my_tool.lockHead)

Test in console:

>> C.scene.my_tool
bpy.data.scenes['Scene'].my_tool

>>> C.scene.my_tool.lockHead
False

>>> C.scene.my_tool.lockHead = True
>>> C.scene.my_tool.lockHead
True

Trying on bpy.types.Window is an issue. The use of bpy.props is restricted to ID types.  As a rule of thumb  objects in the bpy.data collections are ID type..  Scene type in bpy.data.scenes.  There is no bpy.data.windows for the Window type.  (there is the window manager)

>>> isinstance(C.window, bpy.types.ID)
False

>>> isinstance(C.window_manager, bpy.types.ID)
True

>>> bpy.types.WindowManager.my_tool = bpy.types.Scene.my_tool
>>> C.window_manager.my_tool.lockHead
False

Only a rule of thumb test, as shown by a pose bone.

>>> bpy.types.PoseBone.my_tool = bpy.types.Scene.my_tool
>>> C.active_pose_bone
bpy.data.objects['Armature'].pose.bones["Bone"]

>>> C.active_pose_bone.my_tool.lockHead
False

>>> isinstance(C.active_pose_bone, bpy.types.ID)
False

A more robust test, If a blender object doesn't support ID properties, it cannot be used to store custom properties defined with bpy.props

>>> C.window["x"] = 3
Traceback (most recent call last):
  File "<blender_console>", line 1, in <module>
TypeError: bpy_struct[key] = val: id properties not supported for this type


Select the two ends you want to join in editmode and press F. If the shared ends are in the same place, you might want to delete one of them before connecting the curves.


Calculate angle between two vertices of two different objects

I guess that when you ask the angle between vertices, you mean the angle between the two vectors, starting from the origin and going to the two vertice. Those Vectors are actually the coordinate of the vertice but I prefer to be clear to avoid misunderstanding since the angle between two points dont realy make sense.

So it is actually very easy to obtain an angle between two vectors, you can use the Blender implementation of vectors to do that:

mathutils.Vector((v0.x,v0.y,v0.z)).angle(mathutils.Vector((v1.x,v1.y,v1.z)))

(I usually prefer to work with noramlized() vector but I dont think it is necessary for Vector.angle()

BUT:
if you want to compute the angle of the two vertice from the center of the sphere, then you need a vector starting from the center and going to each Vertice

You can do something like vector0 = vertice0.co - sphere.location to find this vector.

Keep in mind that if the object has some transformations, location, rotation and scale, you'll need to calculate the world vertice position. You can take a look there for this point

If you want to have a perfect mach of the two vertices when they dont have the same z coordinate, you'll need to rotate around a precies vector and not only the z axis. This vector can be find with a cross product that will give you a vector perpendicular to two other verctors. Your vectors do needs to be normalized in this case

axis = vector0.normalized().cross(vector1.normalized())

If you want tho obtain the angle so that the the rotation on the z axis will align the vertices, except in the z axis, you should compute the rotation on vectors based on a projection of the vertices on a plane with a z normal. To keep it simple in your case, you can juste set the z value to 0 for each vector then normalize them.

Tell me if you need some clarifications on some points.


From Blender's web page:

  Download latest builds from the 2.7 series

  Blender 2.79b is the last bugfix release in the 2.7 series.
  The last Blender 2.79 nightly build includes additional bug fixes and new
  features on top of 2.79b, which are part of 2.80 too.

So, I suppose this is the last nightly build: https://download.blender.org/release/Blender2.79/latest/


You will need to use particles in Fluid mode, perhaps metaballs if you have the ram for it. This will give you the blobby appearance then render with motion Blur. You'll need to duplicate the particle settings and emitter for blur.

Use vector blur but you can only use Blender internal for that. Make a normal object particle duplicate of the metaball cascade, on a separate layer. Apply this vector blur to the metaball layer.

In the compositor use the 2nd render layer to drive the vector blur.

Results with and with out blur, change vector object  scale to suit blur.

You may have to adjust the particle life of the vector object so that you don't get blurring of the floor.


So i solved the problem only thing you need to do is to enable the ,,High Quality Normals"


BGE: Is there a way to stop my character moving?

You simply need a timer of some sort that must be at a certain value before another attack can be performed. I like using an integer property and adding to it, rather than a timer property because it gives me more control.
Basics of the system require a property sensor to sense if enough time has passed yet; a property to time; an actuator in incrementally add to the timer (only if not using timer type property) and an actuator to set the property to zero whenever you do attack. The system pictured below also has a cap, so the property doesn't go to high, although it really doesn't matter.

you may have to click the image to see it closer. :)


Does a child object inherit the matrix from the parent?

Basics of Local and Global Coordinate systems

Each object in blender has a number of matrices. Its global transform matrix ob.matrix_world its local space matrix ob.matrix_local.  The basis matrix ob.matrix_basis, this is what you see in the "editor"

and its parenting matrix ob.matrix_parent_inverse (This is set when choosing parenting Keep Offset for example)

Relation between basis and local

ob.matrix_local = ob.matrix_parent_inverse @ ob.matrix_basis

As an example, select an object and calculate its global matrix by going up the hierarchy chain.

import bpy
from mathutils import Matrix

context = bpy.context
ob = context.object
M = Matrix()
print(ob.matrix_world)
while ob.parent:
    M = (ob.matrix_parent_inverse @ ob.matrix_basis) @ M
    ob = ob.parent

M = ob.matrix_basis @ M

print(M)

similarly

import bpy
from mathutils import Matrix

context = bpy.context
ob = context.object
M = Matrix()
print(ob.matrix_world)
while ob.parent:
    M = ob.matrix_local @ M
    ob = ob.parent

M = ob.matrix_local @ M

print(M)

Result on test case, Cube is parent of Cube.001 is parent of Cube.002 some random transforms applied to each.

<Matrix 4x4 ( 0.3256, -0.9107,  0.8122, -3.8782)
            (-0.6125, -0.9379, -0.8588, -6.2457)
            ( 1.5886,  0.1065, -0.9282,  4.2578)
            ( 0.0000,  0.0000,  0.0000,  1.0000)>
<Matrix 4x4 ( 0.3256, -0.9107,  0.8122, -3.8782)
            (-0.6125, -0.9379, -0.8588, -6.2457)
            ( 1.5886,  0.1065, -0.9282,  4.2578)
            ( 0.0000,  0.0000,  0.0000,  1.0000)>


Adding Bend Modifier for a parent object and treating as if it's a single object

As explained in the comment, you can use a lattice to do that.

The idea is the following:

Create a lattice and scale it appropriately (1x2, as for the plane mentioned in this answer). Scale it in object mode (edit mode will give a bad result deforming the curves later).
Give it the resolution you want, ie 20x40x1

Bend it using 2 empties

Now add your curves, rotate and scale them to fit the same size as the lattice
Add a lattice modifier to one of the curves
Then link the modifier to the others CtrlL then 'modifiers'

edit the blend file:

Concerning Russia, I think this is due to that:

If you convert it to mesh, lines are going east/west for a long distance, so when bent, that does not work: "these lines are like the string of a bent bow"


Boolean Modifier Help - Difference - Surface Remaining

That should work using 2.91 version of Blender with "Exact" option for the boolean:

"Fast" option behaves as the boolean of the previous version.


What's the fastest way to select every other vertex of an edge ring?

In edit mode with entire edge ring selected:

Select> Checker Deselect

This should deselect every other vertex.

You can then use the 'offset' value in the toolshelf if you want the other vertices in the edge ring selected.

No Offset:

Offset by 1:

Note: This works in edge and face mode too, deselecting alternate edges or faces to get a checkerboard selection.


Animate dog character with soft body physics "jello" legs?

If I want to combine soft body physics with an armature, I usually do it via a dynamic mesh deform:

Suzanne has an armature modifier followed by a dynamically-bound mesh deform modifier.  The target of the mesh deform modifier is bone parented to an appropriate bone-- here, to Suzanne's ear bone-- and has soft body physics, with a goal group and the default goal strength set to 1.0.  There is plenty you can do to further tweak the physics.  The quality of the mesh deform can be increased by using a vertex group to limit it, or by creating an outer shell with full goal, to smoothly interpolate from physics-based deformation to no deformation.
An alternative here is to track the positions of soft-body vertices (or rigid body origins) with your armature.  For example:

Here, I've marked vertices in the soft body with vertex groups that the armature uses for damped track and locked track constraints, so that the bone automatically follows what the physics does (to a certain extent).  The soft body in this case is not bone parented to the ear bone, but to the ear bone's parent.  This can be done with rigid body physics as easily as with soft body physics, by tracking the origins of rigid body objects instead of marked vertex groups.


Maybe try bendy bones? Select your armature and in the Properties panel > Object Data > Viewport Display, choose B-Bone. Then in Edit or Pose mode, select a bone and in in the Properties panel > Bone > Bendy Bones, increase the Segments amount:

Here is what it gives (compared to bones with one segment only), you can play with Ease In and Ease Out values:

You could also use more than 2 bones, some with one segment, others with several:

What you show is special though, as the outer sides are flat while the inner is round, so maybe a corrective shapekey for the inner curve and a driver to activate it?


Different start and end frame for each action

No you can't set a start/end frame for each action as the start and end frame is a setting that is global for the current scene.
Pressing Ctrl + End while your cursor is over the timeline will set the end frame to the current frame. A quick click at the last keyframe and a keystroke is easier than manually entering the end frame number. You can also press Ctrl + Home to set the start frame. This only works when the cursor is atop the timeline panel.
There is also a preview frame range setting, this allows you to adjust the start and end frames while animating without changing the frames that are used when rendering. This is useful when you only want to play a section of the animation that you are concentrating on.
The preview range leads to a shortcut that makes changing the frame range even easier while animating, press P and drag from the start to end frame to set the preview range. This works in any of the time based editors - timeline, dopesheet, graph editor, NLA editor, video sequencer.


This can be done by having two integer properties. One called SpeedRaw and another called SpeedCorrected - the names really do not matter, you will be fine as long as you know which is which.

You simply need to check if SpeedRaw is negative. If it is, it will assign SpeedCorrected the value of SpeedRaw *-1. If SpeedRaw is positive, SpeedCorrected will simply be the same as SpeedRaw.

The end result works as follows:

This also works for float values, however the second property sensor needs to detect when SpeedRaw is greater than 0, not -1.


How to convert textures into materials per each triangle in blender

It is not what did you ask for, but might be helpful. Add-on Bake to Vertex Color takes image texture with UV map coordinates and creates (bake) colors into vertex color (you can find it under Data Properties > Vertex Color. It doesn't take an average, but certain pixel under vertex.

Note:

To generate average color usually ends with a braun color :)
There can be also stored color per face instead vertex, but I'm not experienced with that.


Cloth falls inside object rather than on top

Please try to untick Single Sided in the Softbody and Cloth menu of the mattress collision.


Why does my object appear flat when rendering?

You have no light in your scene, add a sun, spot, point or anything to give some light


hotkey "I" for insert keyframes does not work in pose mode

your mouse should be in the view port to add key frames , or else enable auto key framing


Where is Data Transfer Modifier on Blender 2.73a for Linux?

The data transfer modifier is new in 2.74, you can download RC1 here: http://download.blender.org/release/Blender2.74/


How do I simulate an image texture being spray painted onto a model

Blender Guru has a great tutorial on using dynamic paint.
https://www.blenderguru.com/tutorials/how-to-create-realistic-rain
Using this technique you could make a particle system that looks like spray paint using it as a brush you can reveal a graphic wherever your particle system touches.


How can I bevel geometry that approximates a curve?

All you need to do is remove this stray vertex here (merge the vertex with the one above it and dissolve the edge) to make all sides edge-loops.

Then everything bevels beautifully.


Is it possible to show glass as being transparent in the viewport

The "Viewport Alpha" settings do not seem to work for the Glass shader the way it works for the Transparent shader (or a mix between Transparent and another shader).  However, if you set the Viewport Alpha to "Add" you will get a sort of fake viewport transparency, which looks about the same for any shader.  Maybe that's good enough for your needs?

Otherwise maybe keep a couple of different shader setups in your material.  Use a simple mix of transparent and glossy (or diffuse, or whatever) for your viewport editing needs.  When it comes time to do a "real" render, switch the inputs to your glass shader.

Edit: here is how these options look in the viewport ("Material" view), as suggested by @LukeD:

The cube and suzanne to the left have the same material.  It is a glass shader, with Viewport Alpha set to "Add".  The cube and suzanne to the right share a different material.  It is a 50/50 mix of transparent and glossy shaders, with Viewport Alpha set to "Alpha Blend".


bmesh.ops.transform() expects a 3x3 rotation matrix or 4x4 transformation matrix each for matrix and space.

matrix specifies the desired transformation, which can be anything with a 4x4 matrix (translation, rotation, scaling, skewing, mirroring etc.).
space specifies the space in which this transformation is supposed to happen in. If not specified, the transformation will happen in local space (object space). If you give it the object's matrix_world, the transformation will happen in global space (world space). But you can give it any desired space if necessary (e.g. to rotate around an arbitrary point in space instead of the object's origin).

Simple example:
Translation in local and global space of an rotated object

Mesh with no transformation applied yet. The object is rotated by 45° around X.
Translate mesh 1 unit up on Z-axis in local space:bmesh.ops.transform(bm, matrix=Matrix.Translation((0,0,1)), verts=bm.verts)
Same as 1.
Translate mesh 1 unit up on Z-axis, but using matrix_world of the object to perform the transformation in global space:bmesh.ops.transform(bm, matrix=Matrix.Translation((0,0,1)), space=bpy.context.object.matrix_world, verts=bm.verts)

Giving a space-matrix is the same as multiplying the inverse of the transformation space matrix by the transformation matrix and the transformation space matrix:

matrix_world = bpy.context.object.matrix_world
bmesh.ops.transform(bm, matrix=matrix_world.inverted() * Matrix.Translation((0,0,1)) * matrix_world, verts=bm.verts)

Matrix tutorial:
http://www.opengl-tutorial.org/beginners-tutorials/tutorial-3-matrices/


Cloth simulation acting wonky in render. Correct in viewport

It would be nice to see what it is doing in the final render. However, normally when something like this happens, either you have a subdivision surface modifier on the object with cloth and you have settings set differently on the view port than the render. This would apply into the same concept as other modifiers that you could have on the object with cloth simulation. It does not sound like subsurface. But, works the same depending on the mod. Obviously, something that is checked on for render in your scene and is set different to view port is affecting your final results.


GeForce GTX 760: Unsupported Graphics Card or Driver

I was finally able to figure it out.

Had to go into my BIOS and disable the integrated graphics (again), then completely uninstall the AMD Catalytst Control Center, then uninstall and reinstall Blender again.


To see all objects in the scene:

in the 3D Viewport footer: : View -> View all
or press Home

If you have a mouse with a mouse wheel:

Scroll with the wheel.
Or press Ctrl MMB  then as long as you keep the the key and the MMB  pressed, you can zoom in/out by dragging the mouse.

If you have a 2 button mouse:

Open user preferences
Open the Input Tab
enable Emulate 3 Button Mouse
then you can press Ctrl Alt then click LMB  and drag the mouse to zoom in/out


UV Image Editor won't allow me to search for textures

Your very top editor is the uv image editor, but to use it you need to drag that whole bar down to see the window - what you think is the uv image editor is actually a node editor, and below that is the 3d view and then the timeline.

Use ctrl-left/right arrow to get to the UV Editor layout, and then use the button next to the 'New' button to browse that available images in the file - if there is an image texture in the cup's material, then it shoudl be available to open.
[![

edit: your material for the cup doesn't have an image node hooked up, and there isn't an image to go on the cup material in the file. Looks like you need to add an image node and then open the image you say you have in the mtl file, or go back to blender render and try to import the object with the mtl intact to get the image in the material.
Image as reference for the UV Image Editor]1]1


In fact, the rotation locks are applied to the local axes. As long as the bone is oriented correctly, you will get the correct results. When creating multiple copies and rotating, you must make sure to adjust the roll of the bone (in Edit Mode) in the Bone properties tab to the correct direction.

To confirm the orientation of the bones, you can go to the Armature properties tab, and under Display, check Axes. Now when you look at your bones, the tip of it will display the directions. Keep in mind that the axes will display at the tip, so don't get confused by another bone connected to the base as it only applies to that bone.

From there, you can choose your IK locking settings for the bone according to what the bone's display shows.


Is there a software to reverse normal maps?

The process you are describing is called "Baking". You can follow this process to do this, baking from selected to the active mesh: https://www.youtube.com/watch?v=MnipHJAQJbQ
Marmoset is a dedicated baking tool and has a lot of features and optimizations that make it especially efficient. You can also do this in substance painter. Other 3d softwares also support baking, but are not their specialty


How to get even gradient repetition using modulo?

This is really simple. What you need is to, first, modulo the gradient texture by a value that is less than one and then divide by that same value:

The problem you're experiencing is due to the image's resolution. The only way to fix this is to render to a higher resolution image.

Here's the .blend:


Is automatic "Reload from disk" confirmation in Text Editor possible?

Using a draw callback

Investigated a few ways to do this for an edit with vim addon I put togeter. In the end didn't go with any,

My first choice would be using the loophole in the draw callback that lets us manipulate properties, which you cannot do from a draw method. The red lifesaver on text editor header is drawn when text and text.is_modified. I have left in the reload method I use, however it doesn't update the text.is_modified. I've used the reload operator instead for this question. (intead I use os to keep tabs on file modified time)

If the test script below is run from blender text editor it will add the draw callback.  To use from an addon or such, would import the class and instance it, that way it can be removed, or stopped by calling instance.remove_handle().  An update on a boolean property to turn on and off could be another alternative

The script.

import bpy

def reload(text):
    fp = bpy.path.abspath(text.filepath)
    text.clear()
    with open(fp) as f:
        text.write(f.read())
    return False

class DrawingClass:
    lock = False
    def __init__(self, context, prop):
        self.prop = prop
        self.handle = bpy.types.SpaceTextEditor.draw_handler_add(
                   self.draw_text_callback,(context,),
                   'WINDOW', 'POST_PIXEL')

    def draw_text_callback(self, context):
        if self.lock:
            return
        space = context.space_data
        text = space.text

        if text and text.is_modified:  # if is_modified(text):
            print("reloading text")
            bpy.ops.text.reload()
            '''
            self.lock + True
            self.lock = reload(text)
            '''

    def remove_handle(self):
         bpy.types.SpaceTextEditor.draw_handler_remove(self.handle, 'WINDOW')

if __name__ == "__main__":
    context = bpy.context
    dc = DrawingClass(context, "Draw This On Screen")

Other approaches worth considering:

A modal timer operator. See  text editor > templates > python > Operator Modal Timer .  The issue here is that while a modal timer is running, you may be turning off auto-save.
A scene update handler.  (IMO a pita, as it runs toooooo often)


How to cut and paste part of a mesh to another mesh?

You can't do it using the normal copy and paste functions, but you can do it using a few separate shortcuts/tools:

To 'cut' part of a mesh to a new object:

1. In edit mode, select the parts of the mesh you want to cut.

If you want to copy part of the mesh and not cut it you will need to do step '2', otherwise skip to step '3':

2.  Press Shift+D to duplicate the selected faces/edges/verts.

3. Press P and choose Selection from the Separate menu. The selected part of the mesh will now be a separate object but you will still be in edit mode of the original object.

4. Leave edit mode and select the new separate object (which will be on  top of the old object).

If you wish to join this into an existing mesh you can continue:

5. Shift select a different existing mesh and press Ctrl+J to join them together.


Intersection Boolean Modifier doesn't work

The meshes used in the Boolean modifier should both be manifold (fully enclose a volume) for consistent results as the modifier works based on the volume enclosed by the mesh. Adding a Solidify modifier to the plane will give it thickness so that the modifier has some volume to work with.


create a full featured product in blender using only the python language

You will have to be more specific because the tools in blender should be sufficient without having to know python.

That being said there is nothing you cannot do in blender using python.

If you drag down the top bar of blender (the line slightly below "File", "Render" etc), you will notice it reveals a window.

Do some actions in blender, and you will see their equivalent python commands. Use these to get started. Good luck!


Hard-Trim a VSE project movie clips for backup/storage

Automating the process would require some work, but https://superuser.com/questions/377343/cut-part-from-video-file-from-start-position-to-end-position-with-ffmpeg has some answers on how to make excerpts from larger videos.

TLDR:

ffmpeg -i in.mp4 -ss [start] -t [duration] -c copy out.mp4

Unfortunately, you'll have to create replacement strips that refer to the excerpt clip and get things frame-accurate again.

While I can imagine writing some python that creates these replacement strips, I am not confident that they will be frame accurate.


Making own layout, Toggling through multiple cameras in a scene

Use Local Camera
Ther's a feature called Local Camera that allows you to specify a camera per viewport.
You can find it in the N bar under view. Just specify the camera for each viewport.

To enable the feature in 2.79 you must disable the  lock local camera and layers toggle in the header (see cursor position below).


I think your problem is how you place edge loops in your mesh over the curved surface.

Since it is a cylindrical surface edge loops cant be placed by simple subdivision, because that will yield a flat planar surface breaking the curvature of your otherwise cylindrical body.

When placing edge loops you need to make sure they are equidistant from the mesh center or use Subdivide Smooth for a curvature approximation.


This is because you are using a Mix shader (Add node > Shader > Mix).

This does not work because:

A color output (yellow socket) is not a valid shader input (green socket).
A shader output (green socket) is not a valid value input (gray socket)

If you instead use a Mix RGB node (Add node > Color > MixRGB), it will work as expected:


Much simpler without operators, using API methods

import bpy

context = bpy.context
scene = context.scene
for o in context.selected_objects:
    # create an empty
    empty = bpy.data.objects.new("%sEmptyParent" % o.name, None)
    empty.empty_draw_type = 'CUBE'
    empty.empty_draw_size = 0.15
    # link to scene
    scene.objects.link(empty)
    # make object parent
    empty.location = o.location
    o.location = (0, 0, 0)
    o.parent = empty

All transforms (loc, rot and scale)

    # make object parent
    empty.matrix_world = o.matrix_world
    o.matrix_world = Matrix.Identity(4)
    o.parent = empty


Can't Select Bones or Bone Tips in Edit Mode

Had the same problem because I was following an old tutorial but the only way I could find was to be in edit mode when adding bones to keep one Amature hierarchy
Hope that helped?


Mesh not following bone (weight painted)

There were problems with your rig. I had to create the Rigify rig over from scratch. First, it wasn't clear that your final rig had ever been generated, because I couldn't find any character controls. Yet there were two versions of the rig, both the meta and the regular. So I found it strange that no controls were visible. I checked the layers, and half of them seemed to be missing. No idea how this happened. At this point, I realized that there was no solution but to restart.
Another issue is that your mesh was bound to the metarig. You don't want that. The purpose of the metarig is to act as a temporary stand-in for the fully featured final rig, so that you can shape it in accordance to your character mesh. Then you generate the final rig from the metarig using the "Generate Rig" button under the Object Data tab of the Properties Panel. After that, you should see your new rig appear, with all the needed character controllers. You should see this new final rig, complete with its controllers before ANY binding is undertaken. After the new rig is generated, you need to remove the metarig, because you are now done with it. In my version of your file, I have moved it aside, rather than deleting it. Some consider it a good practice to keep the metarig around in case you need to source it again later for whatever reason. This way, you won't have to reshape it all over again. But you should still probably hide it. I left it visible so you can see that it is still there, but not in use.
Finally, the topology of your model is problematic in places, particularly in the fingers. You may find that this leads to bad deformations. I recommend downloading Makehuman and using the models it generates. They are really good, the program is free, ridiculously easy to use, and it's designed to interface with Blender well. You can always reshape a model it creates to suit your artistic tastes. And it saves SO much work.


How to interpolate vertex colors in a cube?

In general - each vertex is usually used to store only one color. In your example one vertex consists from three colors. So the only one way to interpolate is to set average color.


Why are my classes and functions not working in Blender 2.8?

Look in system console for errors

Start blender from a system console and note any error or warning messages that pop up during registration.

Where does console output go

How to view python error messages?

Blender 2.8 has a far stricter naming convention for operators and panels.  The operator with bl_idname = foo.bar should be given the class name FOO_OT_bar  (_OT_ indicates "Operator Type")

Here is an adjustment to the code, I have prepended the button to the 3DView header to test.

import bpy

class OBJECT_OT_all_select_delete(bpy.types.Operator):
    """All select and delete"""
    bl_label = "Delete all"
    bl_idname = "object.all_select_delete"
    bl_description = "All select and delete"

    def execute(self, context):

        bpy.ops.object.mode_set(mode='OBJECT')
        bpy.ops.object.select_all(action='SELECT')
        bpy.ops.object.delete(use_global=False)
        bpy.ops.view3d.snap_cursor_to_center()

def draw_button(self, context):
    self.layout.operator("object.all_select_delete")

def register():
    bpy.utils.register_class(OBJECT_OT_all_select_delete)
    bpy.types.VIEW3D_HT_header.prepend(draw_button)

if __name__ == "__main__":
    register()


Material and Textures looks Completely different in Unity

I think it might be the reason that josh sanfelici mentioned.
Also check this https://forum.unity.com/threads/can-blender-2-8-eevee-shaders-still-be-used-with-unity.645271/, that someone mentioned about using HDPR. I am also looking for the answer.


Textures and colors not imported from OBJ file when using Cycles render

As far as I know, cycles does not yet support importing materials due to the great difference in the way materials are designed in cycles.

There are some plugins such as blender material to cycles node converter

http://wiki.blender.org/index.php/Extensions:2.6/Py/Scripts/Material/Blender_Cycles_Materials_Converter

I would recommend importing while under blender internal renderer, than either hand creating the cycles nodes, or using this plugin to generate them.


Having trouble making a keymap work when mouse button is released

Go Preferences and see Keymap.
3D View > 3D View (Global) > View Navigation (Walk/Fly)
set to Mouse , Middle Mouse , Press (or Click Drag)
then
3D View > View3D Walk Modal > Confirm
set to Mouse , Middle Mouse , Release


Spotlight Not Illuminating Inside Building

change spot strength to 1000

change glass material to :

and most important change these: (blend mode and shadow mode)

and you will get :

to change blend mode in 2.79 checkout these answers:
Material Opacity in viewport?
How to see Cycle's material transparency in 3D View


Bone Heat Weighting Failed, no solution works

It's probably failing due to too much small topology. Try to reduce the number of vertices again. Or scale everything up so that more space exists between headband vertices.


How can I fix the non-stitched seam that is present after applying mirror modifier?

The normals issue can easily be solved by selecting all the vertices in edit mode and pressing Ctrl+N (You may need to select the Inside option as well, depending on your mesh). You could also add a solidify modifier if you want to have the normals correct on the inside and outside.

The edge loops can be merged together by selecting both edgeloops, and scaling to zero along the Y axis. All you then need to do is to remove doubles.


How to simulate engines spraying a fluid?

Particles:

For the fluid being blown by a fan/turbine, you could try a particle system.
For a really thin fluid/mist, simulating it as a bunch of spheres is probably overkill.

Instead you could try using textured planes (or Billboards):

Add a emitter plane and rotate it 90 so it is standing on its edge:

Add a Particle system to the emitter plane in Properties > Particles.

Blender Internal:

For BI you can use Billboard particles (these don't work in cycles):

Cycles:

For cycles you will need to use a slightly different technique to render billboard objects:

Set the particles to use an object for rendering in Particles > Render > Object.
Add another plane and add a Track To constraint to make it track to the camera (Select the plane and then the camera, then press CtrlT> Track To constraint):

Set the To and Up settings of the constraint in (with the plane active) Properties > Constraints so that the plane faces the camera:

With the emitter plane active, set the Dupli Object to the plane with the constraint and enable Rotation so that the particles will use the rotation defined by the constraint:

Lower the influence of the scene gravity in Particles > Field Weights > Gravity:

Add a Wind force field (ShiftA> Add > Force field > Wind) and rotate it 90 degrees so it is parallel to the emitter plane:

You may want to tweak the strength in Properties > Physics.
Add a Vortex force field and rotate it 90 like the wind force:

Smoke:

If the fluid is really thin, you may want to try a Smoke Simulation.

Note that until Cycles has volumetrics (planned for 2.7) you will not be able to render the smoke in Cycles.


Since you don't need diff and merge functions, you could organize your files differently. You could create one or more scene files to be used as empty containers and link everything else.

This way you would only commit real changes in linked objects and avoid to commit lots of unchanged binary data.
You can easily switch back and forth·between your scene files to the linked ones using the Edit Linked Library addon.

Related:

Wiki Linked_Libraries
Re-Import obj and replace existing
diff and version manage blender work
Moving a Linked Library


vertices that are not affected by subdivision surface modifier

Try recalculating normals, or flipping the 'not working' ones


How do I focus the camera on a certain area or object?

Tracking

I think the term you wanted to use is "tracking". Focus refers to whether the camera is in-focus or blurred.

Select your Camera
From the Constraints context add a Damped Track Constraint
Set the Target to be your object you want the Camera to follow
Set the axis to -Z (that's the direction the Camera looks out of)

Focus

If you want to set the camera's focus, (as in blur), add an Empty to your scene, then from your Camera settings specify that the Empty is to be used to specify the point of focus. Position the Empty accordingly. Adjust the F-Stop to control the amount of blur.


Will Blender charge me for exporting videos?

No, Blender will not charge you.

Blender is an open source 3D development software that provides free access for anyone to do almost anything they want with it.

Even if it was, you will find that many programs will provide free student copies and accessibilities.

Taken from the licence page:

  This license grants people a number of freedoms:

  You are free to use Blender, for any purpose
  You are free to distribute Blender
  You can study how Blender works and change it
  You can distribute changed versions of Blender

The Majority of restrictions are for the source code and software distribution.

As @Duarte Farrajota Ramos said, you should take a look at the licence if you have any queries.

Good luck with your project and I hope I helped,

BFB


How to curve a cube mesh around a circle perimeter

You can use the "spin tool".
Start with a plane section.
Place the 3d cursor at the center of the circle.
Use the spin tool which will be placed at the 3D cursor location (thanks for the information, Robin). By default, the tool will rotate around the Z axis.

Once the operation validated you can tune the values, such as the number of extrusions and the angle.


Script to export gltf fails with 'Context' object has no attribute 'active_object'

Creating a fake active object attribute on the context and passing it to the operator should work. Try this:
CONVERT_DIR = "my/dir"

import os

def file_iter(path, ext):
    for dirpath, dirnames, filenames in os.walk(path):
        for filename in filenames:
            ext = os.path.splitext(filename)[1]
            if ext.lower().endswith(ext):
                yield os.path.join(dirpath, filename)

import bpy

def reset_blend():
    bpy.ops.wm.read_factory_settings(use_empty=True)

def convert_recursive(base_path):
    for filepath_src in file_iter(base_path, ".fbx"):
        filepath_dst = os.path.splitext(filepath_src)[0] + ".glb"

        print("Converting %r -> %r" % (filepath_src, filepath_dst))

        reset_blend()

        bpy.ops.import_scene.fbx(filepath=filepath_src)

        # create a copy of the context
        ctx = bpy.context.copy()

        # because the active_object attribute isn't created until the user interacts
        # with the scene we create one here but we don't need to set it to anything
        ctx['active_object'] = None

        # pass our context copy with active object attribute to the operator
        bpy.ops.export_scene.gltf(ctx, export_format="GLB",filepath=filepath_dst)

if __name__ == "__main__":
    convert_recursive(CONVERT_DIR)


Why does subsurf modifier cause weird deformation at the end of a cylinder?

Not to get too technical, this is because there is no supporting geometry at the edges where the vertices transition into the larger face (the ngon) and the subsurf modifier will stretch these (for lack of better words) giving the bumpy look.
Two simple fixes are:
Extrude and scale the top edge ring in more to the center
Just select the top ring, hit E and scale it in a bit to the center.

OR
Merge all the vertices on the top edge ring at the center
Select the top edge ring or the top face (the ngon) and hit AltP. You still need to add supporting geometry or the problem will persist. An edge loop near the top edge ring should suffice. It's a flat hard surface so merging to tris should be fine.


Solved. I accidentally marked sharp instead of seams.


Is it possible to export a sequence .abc (Alembic) files and then reimport it with the Mesh Sequence Cache modifier?

"Is Sequence" is used when you have multiple Alembic files that are numbered in sequence. To export & import an animated mesh you don't need to use that. Just make sure your frame range for the export is set correctly.


How to fix "bone heat weighting failed to find solution for one or more bones" I tried everything!

i find the error come from your hairmesh
this may solve the problem


If you hate Windows 10, there are other options. I know you asked about Blender on Chromebook, but you can find non-Windows 10 computers for very cheap or free. I got a desktop with Linux from my local library, and my tech teacher gave me a Windows 7 laptop for free. Try asking around.


Vertices with anything above 0% weight move as if they were 100% weight?

Yes, this is correct behaviour.

The weights associated with bones on a vertex are normalized before the deformation.

A vertex, which is not assigned to any bone vertex group will not move at all. A vertex with two (or more) groups will have its weights normalized. If GroupA and GroupB have weights of 0.4 and 1.6, BoneA and BoneB will the influence the vertex's position by 20% and 80%.

If (as in your case) a vertex only belongs to a single group, that group is "normalized" which results in 100%.


What would be the better hardware to use in cycles?

I think a Intel Core i7 is faster on rendering than a GeForce GTX 960 4GB. If you had A GTX 980 I may had some doubt.


Outliner -> vertex group select, not yet implemented: is it a bug?

I don't think you can select the vertex groups via the outliner (because it is not yet implemented), but you still have to select it via the properties panel --> Data object data --> vertex groups
(in version 2.75 it is also not yet implemented)


Can't figure out why one of my assets is shiny?

The easiest way while you are in Object Mode is to switch to flat shading in the Tools panel. Alternatively you can add an Edge Split Modifier in the Properties Editor.


How to lock the background image to the camera view in 2.8?

With the camera selected, find the camera settings in the Properties window.

Enable Camera background.

Select the image.

The image will now show when using camera view.


You need to copy the numpy installation (or any other Python package) into:

..\Blender\2.69\python\lib\site-packages\

it works with no problem.

Practice: go to the above directory and create a sub-directory these. Go inside these and create a empty file __init__.py.

In Python console inside Blender now if you type: import these it works like a charm. This is the same story for any other package.


Detect if using retina display from python

You can can now access the pixel size with bpy.context.user_preferences.system.pixel_size (commit)

This works for retina scale or bpy.context.user_preferences.system.virtual_pixel_mode