How can I get a random number that is constant per object in a driver?

The normal Python way

As @Mike Pan says, in the regular Python you would use a stable value (like location) and use it as a seed. This allows to get a random-like but predictable result.

def get_random_value():
    import random
    seed = obj.location.x + obj.location.y + obj.location.z
    result = random.Random( seed ).random()
    return result

If the seed remains the same, you will get the same result.
By default in Python, the current time is used as the seed. That's why the results are different each frame.

If you need to do it in a driver

You will have less control, but it's possible too :)
Use http://www.blender.org/documentation/blender_python_api_2_71_release/mathutils.noise.html#mathutils.noise.noise

noise.noise( (x,y,z) )

It gives you a result between 0.0 and 1.0, using Perlin noise by default. Imagine it as a value from a Clouds-type texture at a given pixel position. You have to provide the position as a tuple (x,y,z).

Then you can multiply the result by whatever you want.


Script to separate an object's mesh without using bpy.ops

No, currently the only method for splitting objects uses bpy.ops, there aren't always API equivalents for each blender operator.


Why my background appears a blue, when I set it transparent?

You're compositing the blue background in. Enter the compositor and either mute the Mix node or remove it.


While you are in  Weight Paint mode, you have two choices, either remove the mesh from bone or add the mesh to the bone,

Please see the attach files

For adding mesh control to the bone

For removing the control from the bone

Red means full control, blue means no control, and in between those color, partial controls.


When you hover over a property, you can see its Python property.

Here, it is simply :

scene.render.alpha_mode = 'SKY' # in ['TRANSPARENT', 'SKY']


What would be the best way to round an object to fit a shape?

Personally, I think that for this situation it would be best to round off the geometry in edit mode.  Especially since you will (presumably) be  modeling more details to the mesh such as windows, doors, tail, etc. you will want the mesh to be more contoured.

The way I would do this would be to use the smooth function and then tweak it a little with proportional editing.

To do this first go into edit mode and select everything, then bring up the specials menu with W and select smooth.  You can tweak the smoothing by going to the bottom of the left toolbar (T) or hitting F6.  I used the default smoothing value of 0.5, but increased the repeat value to 6.

Then I would tweak the mesh around using proportional editing, turn proportional editing on with O.  You can set the falloff curve in the footer of the 3D view and adjust the falloff radius with the scroll wheel.  You can go into wireframe view and line up your model with the background image to help with the tweaking process.

Here is what I came up with after a little tweaking.


have you checked that the clip distance is correct in the reflection cubemap? "Clipping Start" should be slightly larger than the size of your object (the glass sphere) and Suzanne must be between clipping start and clipping end.
I suggest to activate "Clipping" in "Viewport Display" in Reflection Cubemap settings as in next image:


Yes vertex colours are exposed as three floating point values, but in the background they are stored as three integers that are clamped to values between 0 and 255. You can see the actual code doing that here.

This would be a decision made to conserve space, a floating point value uses 4 bytes of RAM while the integer used fits in 1 byte, that saves 9 bytes for each vertex. This leads to being limited to the 16.7 million colours that can be stored in a 24bit RGB image when using vertex painting.

Blender supports image formats that store float values, so you could look at using an image texture to get more variation in your materials.


You have the vertex groups for your weights but they are not assigned to the bones, simply rename the vertex group to the same name as the bone they are suppose to be assigned to and that should fix it.


What is the C# Mathf.Lerp equivalent in Python?

Lerp typically means linear interpolation.

Assume A, B, C are floating point values.

Assume C is in the range [0.0, 1.0]

lerp(A, B, C) might be implemented as

value = (C * A) + ((1-C) * B) // convex combination

When C equals 0 value equals B.

When C equals 1 value equals A.

When C equals .5 value equals the average of A and B.

Of course you can switch the factors (C) and (1-C) depending on your desired implementation.  You can also switch A and B depending on your desired implementation.


First convert your curves in to mesh objects, AltC > Mesh from Curve/Meta/Surf/Text.

Now just copy and paste the script below into blender's text editor, then with your object still selected press Run Script.

This script below will draw grease pencil strokes on the active object.

import bpy
from mathutils import Vector

obj = bpy.context.object
mesh = obj.data
scene = bpy.context.scene

pencil = bpy.data.grease_pencil.new("pencil")
scene.grease_pencil = pencil

layer = pencil.layers.new("layer", set_active=True)
frame = layer.frames.new(scene.frame_current)

for edge in mesh.edges:
    stroke = frame.strokes.new()
    stroke.draw_mode = '3DSPACE'

    stroke.points.add(2)
    stroke.points[0].co = obj.matrix_world * Vector(mesh.vertices[edge.vertices[0]].co)
    stroke.points[1].co = obj.matrix_world * Vector(mesh.vertices[edge.vertices[1]].co)

Thanks to CoDEmanX for his making a grease pencil through bpy answer.


compare two same armature structure, rotate first armature's bone to the second position

The following python code copies the bone configuration from the active object to all selected armatures. You do not need to bother with rotation matrix here because the bones are defined in local space, thus the global rotation of the armatures does not need to be taken into account:

import bpy

# Assume, that context.object is an armature
context = bpy.context
scene   = context.scene
source  = context.object

# Targets are all other selected armatures
targets = [a for a in context.selected_objects if a != source and a.type=='ARMATURE']

# Store the bone data of source:
bpy.ops.object.mode_set(mode='EDIT')
bone_store = []
for ebone in source.data.edit_bones:
    bone_store.append([ebone.name, ebone.head.copy(), ebone.tail.copy(), ebone.roll])
bpy.ops.object.mode_set(mode='OBJECT')

for target in targets:
    scene.objects.active = target
    bpy.ops.object.mode_set(mode='EDIT')

    # Transfer the bones to the other armature.
    # The following works because the bone data is defined in local space:

    ebones = target.data.edit_bones
    for bone_data in bone_store:
        bid =  bone_data[0]
        if bid in ebones:
            ebone      = ebones[bid]
            ebone.head = bone_data[1].copy()
            ebone.tail = bone_data[2].copy()
            ebone.roll = bone_data[3]

    # Note: You might also want to copy constraints

    bpy.ops.object.mode_set(mode='OBJECT')

scene.objects.active = source

And here is a snippet that copies only the pose from one armature to the other:

import bpy

# Assume, that context.object is an armature
context = bpy.context
scene   = context.scene
source  = context.object

# Targets are all other selected armatures
targets = [a for a in context.selected_objects if a != source and a.type=='ARMATURE']

bpy.ops.object.mode_set(mode='POSE')
bpy.ops.pose.select_all(action="SELECT")
bpy.ops.pose.copy()

for target in targets:
    scene.objects.active = target
    bpy.ops.object.mode_set(mode='POSE')
    bpy.ops.pose.paste()


bpy.context.scene refers to the current scene, e.g. bpy.data.scenes["Scene"]

Sequence Editor data is stored in the Scene type, and .sequences contains the the top-level strips.

This iterates over all top-level sequences, whereas s refers to a sequence:

for s in bpy.context.scene.sequence_editor.sequences:

If the sequence is of type SOUND:

    if s.type != 'SOUND':

... the following code block is executed:

        s.use_proxy = True
        s.proxy.build_25 = True
        s.proxy.build_50 = False
        s.proxy.build_75 = False
        s.proxy.build_100 = False

A couple sequence properties are set.

Other sequence types:

>>> [item.identifier for item in bpy.types.Sequence.bl_rna.properties['type'].enum_items]

['IMAGE', 'META', 'SCENE', 'MOVIE', 'MOVIECLIP', 'MASK', 'SOUND', 'CROSS', 'ADD', 'SUBTRACT', 'ALPHA_OVER', 'ALPHA_UNDER', 'GAMMA_CROSS', 'MULTIPLY', 'OVER_DROP', 'WIPE', 'GLOW', 'TRANSFORM', 'COLOR', 'SPEED', 'MULTICAM', 'ADJUSTMENT']

You can pick a single sequence and get the type:

>>> type(bpy.context.scene.sequence_editor.sequences[0])
<class 'bpy.types.SceneSequence'>

Check the API docs to find out about the properties and methods:
bpy.types.SceneSequence

.proxy is a subtype, which has several own properties: bpy.types.SequenceProxy

Don't miss to read this:

Blender/Python API Reference Usage: examples of how to use the API reference docs


Bottom right in the keyframes section you've selected location, remove that you will get the menu when used I key on the keyboard


how to repeat automatic: three selected one skip mesh edge?

Use Checker Deselect to deselect some edges and leave others selected according to the pattern.

To make it run properly select the full ring of edges where are located those shown on your screenshot. If you want complete ring of edges selected then press Ctrl+Alt and click with RMB on the edge.

Make sure to choose active edge as in the screenshot (it is marked with red color, the leftmost one), so it corresponds to those which should be left selected.
Then execute Checker Deselect. Set its properties so it deselects every 2nd element and preserves the pattern of 3 edges together. Set the starting point of the selection with Offset, in this case it's 2.


How to use python classes with BGE objects?

Composition

You can assign an object (instance of a class) by referring from the game object to your instance e.g. by assigning it as value to a property.

import bge
from myClassDefinitions import MyClass

myInstance = MyClass()

owner = bge.logic.getCurrentController().owner
gameObject = owner
gameObject["myClass"] = myInstance # assign object to game object

print(gameObject["myClass"]) # get object via game object

Explanation

The game object and the instance of your class (object) are two separate objects.

After creation you assign your object (as reference) to a property of the game object. This means the game object knows how to get the object at any time later via gameObject["myClass"].

The object does not need to know the game object. If you really need you can create a cross reference (e.g. by storing a reference of the game object as attribute of the object).

Advantages

any number of objects can be assigned to the same game object
any number of game objects can refer to the same object
the property name indicates the purpose of the referred object
the property can be exchanged or even removed
allows to avoid dependencies to BGE from within your own classes (you can test it with unittest, you can use it outside the BGE)
can survive game object remove (e.g. on scene switch) when referred from outside the scene.

(this is another option)

Object replacement

The BGE allows to "replace an existing game object". It is a strange idea but allows to feel like subclassing. It is descibed in the BGE API.

Explanation

You create an instance of your class which subclasses KX_GameObject (or whatever you told your class should inherit from).

The game object in the scene will be replaced by the BGE when instantiating your class (that is why you need to deliver a game object to be replaced).

Your object inherits all attributes from the game object you delivered at instantiation.

When the game object dies your object dies too as it is the game object now.

Advantage

single class
can still use properties
feels like a class

Disadvantage

single class only
replaces the game object (any previously made references to this object become invalid)
dependency to a single game object type branch (you can't use the same inheritance for KX_Camera and KX_FontObject)
will not survive ending the game object (e.g. on scene switch).


You cannot make materials in blender internal and expect them to work on Cycles. Each render engine works differently and the materials created for each one are not interchangeable. If you are going to render using cycles you need to create new materials.

Read:

How is Cycles different from Blender Internal?

Cycles vs internal vs game engine


How to find quicly a duplicated bone name

Highlite it in the list as suggested, look in the 3D window for the gismo arrows.  That's where it should be, even when you cannot see it.  Sometimes these things appear as just a highlited dot in the 3D screen.

Good luck - it's a perplexing problem that one!


Can't be certain, but looking at the gif you provided I can see that the Z value is actually increasing as you move your cursor, even though the model of the ball is not moving.

Given that fact, I suspect a Constraint or Driver is present somewhere which is translating the Z coordinate into different, limited motion. As what you're moving looks to be an animation rig and they're often built with constraints and drivers in mind that also reinforces that guess from me - but without seeing the rest of the file or further details it remains a guess.

From the values in the gif, one of the balls is at around -4 Z, and the other only at -1 Z, and if they're actually constrained to stay within, say, 0 to 3 Z, this explains why they move differently.  You can't see it, but one of them is already lower 'down' according to its own data.


Return a list of activated render passes for view layers?

I am not sure if there is a better method to do this but....
You can test all of the "use_pass_****" attribute in view-layer (and also eevee, cycles):
[
    attr
    for attr in dir(C.view_layer)
    if attr.startswith("use_pass") and getattr(C.view_layer, attr) == True
]  # -> ['use_pass_combined', 'use_pass_mist', 'use_pass_normal', 'use_pass_z']

And eevee-only pass:
[
    attr
    for attr in dir(C.view_layer.eevee)
    if attr.startswith("use_pass") and getattr(C.view_layer.eevee, attr) == True
]  # -> ['use_pass_volume_scatter', 'use_pass_volume_transmittance']

After seeking in Render Layer node, there is a outputs attribute contain different outputs that a node can potentially have. And each output can be enabled by attribute enable:

[
    key
    for key, output
    in C.scene.node_tree.nodes["Render Layers"].outputs.items()
    if getattr(output, 'enabled', False)
]  # -> ['Image', 'Alpha', 'Depth', 'Mist', 'Normal']


Mix colors from different objects at collision (Rigid Bodies and Particles)

Using Animation Nodes
Updated for Animation Nodes 2.0!
Method with the Molecular Modifier and CubeSurfer below!!!
Another way to do this is using @Jacques Lucke's Animation Nodes addon. Here is the final result:

And here is a picture of the node setup:

This is done with a Rigid Body Simulation and Vertex Colors. After installing Animation Nodes (linked above), we can get to work.
1. Setting Up the Scene
First, we have to set up our Rigid Bodies. Add a ground plane, and under the Physics tab of the Properties Editor, click on Rigid Body and uncheck Active. For every object that we want to actively collide, click on Rigid Body, but leave Active checked.

In addition, under the Mesh tab of the Properties Editor, add a vertex color by clicking the + button under the Vertex Colors panel. Since we have to do this for every object, we can save ourselves some typing by leaving the default name, Col.

The last thing we have is give it a material. Call it whatever you want, and then create the following (Cycles) NodeTree:

This can be modified as needed, as long as the vertex color is still a part of the nodetree.
Repeat the above for all of the objects you want to mix color, giving the the same material, or just duplicate the one object. Finally, select all of the objects you want to mix colors and group them together (Ctrl + G). Don't forget to name it, either in the T panel or by hitting F6.

The scene is set up now. Let's dive into the Animation Nodes!
2. Creating the Nodetree
In the node window, click on the Animation Nodes. Add an Objects From Group node (to add a node, either press Shift + A and find the node, or press Ctrl + A to search for it). Select the Group.

The first thing we want to do is to assign random colors to each object on Frame 1. Let's create a subprogram to do that. Add a Loop Input node and name it SetRandCol. Press the + button next to New Iterator and type "Object List". Set up the following nodes:

To activate the loop, add an Invoke Subprogram node, select SetRandCol, and plug in the Object list. It should take effect immediately.

We don't want this to happen every frame, though. Just the first. Add these nodes to make it only work on Frame 1:

Cool. The next step is to calculate all of the different pairs of objects we will have to check collision against. We could do this with nodes, but it is faster to just use a short script. First, add a Get List Length node and plug in the Object list. Next, add a Script node and name it FindPairs. Press the + button to add a new script. Use the buttons to add 1 input (an integer) and 2 outputs (integer lists). Name them as follows:

In a Text Editor window, open the FindPairs script and paste the following:

obj1, obj2 = [],[]

for i in range(0,objcount):
    for j in range(i,objcount):
        if i != j:
            obj1.append(i)
            obj2.append(j)

To use the script, add an Invoke Subprogram node and select the "FindPairs" option. Plug the Get List Length node into the script node. obj1 and obj2 are all the pairs of objects (i.e. index 0 goes with index 0, etc).

The next thing to do is to create a loop that checks every pair for collision. We will do this with the Is Inside Volume node. Create a loop the same way we did the first time. Name it BVHCollide. Give it two "Integer List" iterators (named obj1 and obj2), an "Object List" parameter, and a "Float" parameter named Epsilon.

Add these nodes:

Next, we need to check for collision between the two objects. We'll use the Is Inside Volume node. After we check for collision, we'll combine our data to get a single boolean value for whether or not the two objects intersect:

The Epsilon parameter determines how far outside the loop the BVH node will look. Usually a super-low, non-zero value will work, like 0.0002. The last thing to do is to change the color of the objects. Add one more loop:

In the Advanced Node Settings dropdown of the N panel for the Expression nodes, be sure to uncheck "Correct Type":

Finally, invoke this last loop, and your simulation should work!

Blend File (requires Animation Nodes):

If you want to set the color manually, you can create this loop. Just provide it a list of colors with corresponding indices to the list of objects:

Incorporating the Molecular Modifier
Incorporating the Molecular Modifier has a similar workflow to the Rigid Body Method. Begin by setting up a Molecular simulation. Here is mine:

Here is the final result:

Node setup:

After setting up the molecular simulation, we can work on the coloring. To color the particles, we are exploiting a feature of the Molecular Modifier: since the entire simulation is baked with its own physics, the particles never rotate and therefore never use the Angular Velocity attribute. We will store our colors there. Set all of the particles to render as an Icosphere object and give the Icosphere this material:

Now lets get into Animation Nodes. Unfortunately, in Animation Nodes 2.0, the Particle datatype has been removed. The most efficient way to get around this is to create our own in Python. First, let's create an Extract Particles node. Add a Script node, and give it Particle System input and a Generic List output. Name the List ParticleList. Create a new script file and paste in this code:
ParticleList = []

for p in ParticleSystem.particles:
    ParticleList.append(p)

Next, we need a Filter Particles node. Add another Script node, and give it a Generic List input, four Boolean inputs, and a Generic List output. Name them as follows:

Here is the script:
Filtered = []

for p in Particles:
    if Unborn:
        if p.alive_state == 'UNBORN':
            Filtered.append(p)
    if Alive:
        if p.alive_state == 'ALIVE':
            Filtered.append(p)
    if Dying:
        if p.alive_state == 'DYING':
            Filtered.append(p)
    if Dead:
        if p.alive_state == 'DEAD':
            Filtered.append(p)

Last, we need a Particle Data node, to get information from the particles. Add another Script node, and give it a Generic List input, a Vector List output, a Float List output, and a Color List output. Name them as follows:

Here is the script:
Locations, Sizes, AngularVelocities = [],[],[]

for p in ParticleList:
    Locations.append(p.location)
    Sizes.append(p.size)
    AngularVelocities.append(p.angular_velocity)

For some reason, Animation Nodes doesn't like us using a Color List to store vector data, so disable Correct Output Types in the Advanced Node Settings panel of the N sidebar for the Script Node:

Now that we have that set up, we can get on to coloring the particles. For each of our particle emitters, add a Particle Systems from Object node. Add one of our ExtractParticles nodes for each Particle System:

We need a way to color the particles. Create a new Script subprogram named Color Particles. Give it two Color inputs and one Generic List input:

Code:
for p in particles:
    if color1 != color2:
        p.angular_velocity = [(color1[0]+color2[0])/2,(color1[1]+color2[1])/2,(color1[2]+color2[2])/2]

To set the initial colors for each particles system, use a FilterParticles node to get unborn particles, then the Color Particles node to set the color. Note that the two color inputs have to be different for the node to take effect:

Now, join all the particles together with a Combine List node and use a FilterParticles node to get a list of all Alive particles:

Next, we need to calculate all the different pairs of particles to check collision for. We can just use the same node we created above:

At this point, the numbers start to get really big, and unless you have an über-fast computer, you're going to start to lag. Even then, this NodeTree works better if it's only executed once a frame. If you haven't already, you should turn off Always in the Auto Execution panel of the T sidebar:

Ok. Next, let's check collision. Since everything is a perfect sphere, the math is pretty simple. The Loop node will need 2 Integer List iterators (obj1 and obj2), a Vector List parameter, a Float List parameter, a Float parameter, and a Boolean List output. Here is the NodeTree:

We can invoke it like so:

We now have a problem. We have an enormous amount of data. For my little 8000 particle simulation, there are over 2 million particle pairs that have to be checked for collision. If we also have to check if they need to have their colors modified, it would take forever. So, we should optimize the lists to only have pairs for which collision is true. Create a Script node with an  Integer List and a Boolean List input and an Integer List output:

Here is the script:
n = [i[a] for a in range(len(i)) if b[a]]

Use this Prune node on both of the obj lists:

Lastly, we need to change the color of all the colliding pairs. Since we already have a script to calculate and change the color of a pair of particles, we don't have to do much. Create this Loop:

Make sure to change the Slice Type from Index to Length. To finish, put in the Update Particles node:

Done!!!
Notes:
This will not run in real-time. For an 8000 particle simulation, it takes my (about average) computer 6-7 seconds to calculate each frame. Realize that the number of pairs increases quadratically, not linearly, so a 10000 particle simulation will take roughly four times as long as a 5000 particle simulation, depending on how many collisions there are.
Be sure to save before rendering. With both the Molecular script and Animation Nodes running, my computer froze once while rendering (I only have 8GB of RAM, though).

Blend File (requires Animation Nodes and Molecular):

Using CubeSurfer
We can even mesh our simulation and transfer the colors from the particles to the mesh. I'm using CubeSurfer to mesh my particles. It's pretty easy to pick up (controls are at the bottom of the Object panel) and there are tutorials online. Doing this will slow down the simulation a little more, but the NodeTree is pretty simple:

The two Reroutes are bringing in the list of active particles, and the locations of those particles, as labeled, from their respective nodes in the Main frame of the previous NodeTree. The object in the Object Input node is the Isosurface object created by CubeSurfer. You'll need to enable visibility for the Polygon Centers output of the Object Mesh Data node in the N panel. Here is the SetVertexCol script:
Object.data.vertex_colors.new() #Add a new vertex color, since it gets deleted at every frame change.
v_colors = Object.data.vertex_colors["Col"].data #Get the vertex color data
colors = [ParticleList[i].angular_velocity for i in Indices] #Get the colors for each face from the particles
i,j = 0,0
for f in Object.data.polygons:        #Iterate through each face
    for l in f.loop_indices:          #Iterate through each vertex
        v_colors[i].color = colors[j] #Paint vertex with color
        i += 1                        #Increment vertex
    j += 1                            #Increment face

The above code works because Vertex Color data is stored as a list of colors sorted by face, then vertex, which happens to be in the same order the Animation Nodes gets the faces.
Final Result:

It looks pretty awesome. Unfortunately, converting it to .gif form took down the quality. You can watch the full clip on YouTube here. I recommend watching in slow motion so you can see it frame by frame.

Blend File (Requires Animation Nodes, Molecular, and CubeSurfer):


There is a great exercise that I came across from a YouTube tutorial by Josh Grambrell who demonstrates a great way to work with Booleans in a non-destructive workflow.
link here: https://www.youtube.com/watch?v=LdQwmfPyuw0
But more importantly to answer your question a little closer, the youtuber gets his reference from an Artstation blog post by Frank Oczur Jr. who talks about different workflows using including subdivision modelling exercises. I'll post he link as well.
https://www.artstation.com/frankpolygon/blog/M7w7/sub-d-hard-surface-modeling-v-block-exercise-amp-tutorial
I won't try explain it myself as I'll probably butcher their work but both are really good reads and a video to watch which might help answer your question.
Hope this helps


Try CtrlAltZ. That wiki page is for Blender 2.4x.

Here's the 2.6x page (which is current for 2.7x, as there is no 2.7x wiki yet)

If you want to access it from a menu, it's in 3D view > Header > Object:

If you want to access it from a toolbar, it's in 3D view > Toolshelf (T) > Tool > History:


How to remove certain part of the object name for hundreds of objects?

For selected objects:

import bpy

for o in bpy.context.selected_objects:
    o.name = o.name.replace("marketing_", "")

Or for all objects in the scene:

for o in bpy.context.scene.objects:
    o.name = o.name.replace("marketing_", "")

Or for all objects in the file:

for o in bpy.data.objects:
    ...


Where do I find the latest Blender release?

The latest production-ready version can be found on
  www.blender.org in the downloade page. (Direct link - blender.org/download)

 Finding the right version

If you are unsure of what version you should use, try the one that the page suggest with a big button. If you are denied to install or start it, go to the list of other versions and see if an archive (.zip / .rar / .7zip example given) version that matches what was recommended from the page. Open the archive and copy the folder that is in it to the desktop or where you like to keep your files. You start blender by launching the executable (same thing as a program) blender and not BlenderPlayer. (if the page recommended a 32bit version a 64bit is unlikely to work)

  If you have come this far. If someone does call you on the phone from a number you don't recognize and offer you support, say that you will call them back and only do that if the number belongs to someone you can trust.

If neither the recommended version or the archive work ask your support for help or computer administrator if needed. (The administrator will probably appreciate that you asked the support first)

If you don't have any support you can try this steps to find what OS you have and try the version for that instead.

If you have an interface that is based on typing on your keyboard to enter commands only. Ask the person that installed it or gave it to you for help, otherwise, go to your local computer store and ask for help.
Enter mmc.exe in the search bar and if you can launch the program you have windows. Try the different 32bit versions or if it complains and wants a 64bit, try them instead, otherwise test the next step.
If you have a  <- Apple Inc. logo in the corner, press it and go to about this mac. If you can do this you have OS X, otherwise, test the next step.
Contact the person that did give you your computer and ask for help or go to your local computer store and ask for help, otherwise test the next step.
Se if you can find the answer on these pages:

support.microsoft.com
support.apple.com

 Wher to find the latest features/experimental builds

The newest features and build can be found on builder.blender.org and should be considered unstable. Don't save anything with the realizes that you need later because the versions might corrupt the files.

If the version does cause the computer to freeze or crash repeatedly under normal use, go to the builder page and enter the requested information and force a new build for that version if no new have been realized.

If you want one of the current development versions read the wiki.blender.org on how to compile blender from the current code.

!!Do not forget to do the checkout or it will not work!!


I imported a DXF and now I can't add meshes?

Looks like you're in edit mode where SHIFT+A opens the curve menu when you're editing a curve object. Just press TAB to return to object mode or select it from the dropdown.

In Blender 2.7x

In Blender 2.8


Displaying keyframed opacity / transparency in Material mode in viewport?

I am fairly certain this is a limitation of the current system. Simply put the changes in material settings don't trigger updates in the viewport. Manually altering values in the node editor or the material properties causes the UI to deliberately send an update event to the viewport, keyframed changes during playback don't. The keyframed changes do pass through to the render engine though.

I wouldn't expect this to change until the new dependency graph work is finished.


Select the inner Vertices, press W > Smooth and adjust Smooth Vertex settings:

You can also access Smooth Vertex operator settings via F6:

Another way is selecting a whole row or column of vertex and then Scale in X or Y axis to a factor or Zero with S > X + 0

Alternatively place the 3D cursor over the vertex you wish to align to, press . to transform relative to the 3D Cursor position, and then repeate the scale process described above. S > X + 0


How to smooth an arrayed object so the breaks between objects are less obvious?

Using an empty with a scale factor, you will also need to proportionally scale one end of your mesh so it matches the scale factor given to the empty.

You can instead try an array modifier with the fit curve option, and use a bezier curve to drive it. Then use a curve modifier afterwards and control the downscaling with the curve radius by entering Edit Mode in the curve and pressing Alt + S on the tip vertex.

Don't forget to delete the top faces of your tentacle segment mesh so there are no internal faces.

The downside of this technique is that it will always give some stretching effect caused by the radius not affecting curve length.


How do I copy one side of a box and paste it on the rest of the sides?

To "copy" the detailed side to all four sides, I use a array modifier, and an empty.

Start by adding an empty at the same location as your cube. Rotate the empty 90° along the Z axis.
Edit your cube to look like this, or without the top and bottom triangle.

Add a array modifier. Set the Count to 4, uncheck the Relative Offset and use the Empty as the Object Offset.

If you only want the detail on the opposite side

Add a loop cut down the middle (perpendicular to the X axis).
Delete the half of the cube that you have not yet modeled.
Add a mirror modifier to the object.


Blender 2.8 crashing after starting render

Found what was going on. Needed to bake the animations for each of the particles systems.

I am unsure if this is something you are supposed to do when using particle systems, but I had not baked any of them to memory, and considering the render had worked before with fewer systems, I figured it wouldn't be necessary. Ran the render after baking each of them and it worked as expected.


icosphere passes through all planes even with collision on in physics tab

I think you need to simplify the physics models.  Here is what I have for the blue ball and then the stairs:

I didn't change any of the soft body parameters, using the defaults instead. I did set the stairs to Passive and made sure the blue ball was active.

Since I didn't tune the rigid body parameters, the balls tend to pass part way through the stairs, but they do bounce and roll down the stairs.


Subdividing a beveled mesh creates new vertices in wrong places

This happens because you have a face made up of more than 4 vertices (N-GON), and with the subdivided surface, you have to be careful, and try to use a more regular topology. Ngons will not subdivide correctly.

I used the command crtl + T to triangulate the face.


You can select all the faces and go to Mesh> Faces> Triangulate Faces in the 3D View header (or just press Ctrl+T for the same effect) while in Edit Mode.

As ideasman42  pointed out in the comments, Mesh> Faces> Poke Faces (accessible with Alt+P) will also triangulate the mesh by adding a vertex in the center of each face and fan-filling around the vertex, it may give preferred results for certain cases, for example, cylinder caps.

You could also add a 'Triangulate' modifier to the object and apply it:

Visualisation of the two methods:


I don't think there is any way of totally disabling it in blender, but you can get pretty close by changing the theme preferences.

First go to Edit

Then select Preferences

And then in the new window go to Themes -> 3D view -> Face Selected.

Lastly, click the color and turn the lowest value (A or Alpha) to 0 and click at the bottom right of the window "Save Preferences".

Then you should be set.


I used a material.  I had a screen material with two elements in it.  a black screen, and a emission with a movie texture on it.  I mixed them together and then animated the factor of the mix node to make it turn on.

please comment if you need more info,

hope this helps.


Where to find particular colour the theme?

The problem was the Channels were showing Group colors Over the default theme. Deselecting that option"Show Group Colors" from View menu brought back the readability.


Are Cycles particles less voluminous than Eevee particles?

I learned that inside the Particle System, changing the Children from 'None' to 'Interpolated' will add more hair.
If more thickness is wanted, in Hair Shape, the hair root and/or tip can be thickened, producing a similar effect.


How to enable auto smooth option for unreal engine?

You need to set the Smoothing to Face under Geometry when you export FBX.


How to remove light and camera in blender 2.82a

While you are still in Material Preview mode, go to the top-right of your viewport and select the Shading dropdown. Under it is a Lighting section. Look for
Scene World and see if it is checked. If it is, uncheck it. With it checked, the actual lighting in the scene is used in Material Shading.


You have a lot of vertices overlaying, you need to select your mesh, go in Edit mode, select all and press W > Remove Doubles with a Merge Distance (on the bottom of the Tools panel) of 0.01.


API access for workbench render settings

You could try

bpy.data.scenes['Scene'].display.shading.light = 'FLAT'

(thanks to @nicklamer on #blenderpython)


shrinkwrap doesn't go all around a Cylinder

Two questions..

(top row) You're using the wrong projection method in your Shrinkwrap modifier for this case.You have 'Project', along Y of the object space of your array (which is the same as the Y of your original element). Better to use 'Target Normal Project' (along the normals of the target) or 'Closest Surface Point'.
(bottom row) How to get an outward tilt of the peaks? The Shrinkwrap can be modulated by Vertex Weight. Assign a vertex group to the mesh, and weight it with lower values at the peaks. They will be influenced less, if you aim the  Shrinkwrap at the group.


Is there a way to make custom coffee foam?

It's not extremely good, but this should give you a good place to start:

The image you want to appear on the foam is very detailed and hard to reproduce on real coffee. This is why I thought it should be pre-processed in some image editing software to make it more realistic and doable. I used Photoshop to smudge out the image a bit, and I got this:

The coffee itself that I made in Blender was a simple squeezed sphere. I then used the image above as a texture to determine the color of the foam. Here is my node setup for the foam:

I'll go into the details now.

Distorting the image

I used a Wave texture to distort the image in rings. You can adjust the frequency and amplitude of the distortions.

Some noise texture on top of that

I added some noise to the image, because nocoffee is perfect.

Bump map

I didn't have any actual coffee to look at, but I'm assuming that the image should have some effect on the bumps in the foam, due to stirring. So I created some "ripple" bumps around the borders of the texture (kinda):

The coffee shader

Now, we have calculated both the texture we want on the coffee and the bump map. I used a gradient to get the right coffee colors. The actual shader was a simple mix of a diffuse shader and a glossy shader:

Here is my resulting .blend file you can play with:

Here are some possible improvements you could consider:
- It is very easy to adjust how much you want the image to be distorted in rings. In the "Distort Image" frame, just change the second value of the Divide math node.
- Consider introducing a subsurface scattering component, because coffee is transparent. Or, even better, use a volume shader. Coffee is a little bit transparent.
- You could change the colors to make them a little warmer, because my coffee looks like mud. Yuck. :)
- You could further tweak the original image: smudge it, adjust contrast, add noise, etc.


Maybe check in the Preferences > System > Memory & Limits, you need to activate the Global Undo option (but you need to recreate your object).


animate audio spectrum onto a sphere using animation nodes?

I shall show how this can be done in 2.8, but the same applies for older versions. You just transform/multiply your transformations (In this case a circular distribution of matrices) with a scale matrix composed from the frequency bins on one vector component:


How to add a sensor to an object using the BGE Python scripting

There is no function addSensor in the API search_1  API search_2.

So you can't add a sensor through python. The sensor requires to be added in logic editor for a single object, but you can add an object with a sensor and controller to the current scene.


How to avoid subsurf distortions on cylindrical objects?

Although there are several ways to do this, I would recommend selecting the outlining edges:

And then bevel them with Ctrl+B:


BlenderAndMBDyn installation - Action tab missing

If you start blender from a terminal window you should see some errors when you try and enable the addon, if you start blender from the application menu these errors will be hidden.

While the addon says it is compatible with 2.60 my quick tests with several versions show that it requires at least 2.70. It would be worth reporting that to the developer so that they may update the minimum requirements or adjust it to be compatible with older versions.

Waiting for the developer to update the script for older versions may not happen so you probably want to update your copy of blender, which would be recommended in general. It appears that the ubuntu packages for blender have not been updated for a while, you may want to look into getting a newer version. This answer seems to have the info of a PPA that is up to date.


On the Blenrig body picker, where it says arm_L and arm_R just change the hinge to 1.


A typical way would be simply to duplicate the bottom edge of the wall, and convert it to a curve, down which you can sweep a profile of the molding.

ShiftD Duplicate the bottom edge of the wall
P separate it into its own object, and Header > Object Menu > Convert it to a curve. (The 'Path'). Make the path a 2D curve, to ensure clean miters.
Construct a profile for the molding, either as a mesh which you convert to a curve, or as a curve in the first place. (The 'Profile')

Note the orientation of the profile curve with respect to its object axes, and the position of its origin at its bottom left corner (shown with the 3D Cursor). All this can be adjusted in Edit Mode.

Now just assign the 'Profile' curve as the Bevel Object of the 'Path' curve.

You might want to convert the 'Path' curve back to a mesh when you're done, to make Auto Smooth available for it. That way, you can keep the poly count down.


How to apply texture to one face of an object in cycles render?

You need to assign the material to selected faces in the materials tab.


Is it important to model a car to be subdivided in all quads or will tris work?

When tris get subdivided, they become quads. Use tris in your mesh sparingly.

At regular intervals or when you're finished with modelling, you must check for double points in mesh before unwrapping or rendering. To do that, select entire mesh, press W and remove doubles. Note: Doubles occur when you use mirror modifier. So always remember to remove doubles before ever rendering - otherwise you will have rips in rendered mesh.

Whenever I get stuck on topology, I always go to Pinterest for ideas - TONS of ideas and sources for inspiration. If you haven't got Pinterest, it is time that you start a new account there. Pinterest is where you pin pictures to your boards: those on topology, node compositing, alpha brushes, etc.
In this link, my board is called Mesh Studies and I collect others' topology works. I have those for hands, feet, faces, etc.
https://www.pinterest.ie/ritag2/a-mesh-studies/


How can I get a vertex count for an edge loop in Python for Blender 2.8?

Or you could also do:

import bpy
import bmesh

selected_verts = [v for v in bpy.context.active_object.data.vertices if v.select]
count = len(selected_verts)
print(count)
```


Cannot find uv option in texture mapping in Blender 2.72

This is correct, world has no vertices so it cannot have UVs.


How do I apply force to an object that must move with the forehead?

I solved it. Found a blend showing what I needed.

http://bulletphysics.org/Bullet/phpB...69367c52979f40

If you're up for seeing it yourself in action, all I did was add 3 bricks below there's (of the top cube) that makes it move ex. left when you press A. I used Simple Motion. And was able to record it into Cycles. Looks good. Gravity is natural anyways and won't show up in the face springs.


Can I assign the vertices created by the solidify modifier to a new vertex group?

You can use a workaround to select them all at once.
If the modifier isn't applied
Assign generated faces to new material and select by material
Create one more material for your object, you may leave its default settings
as they aren't important. The only thing which may be changed is the name of the material so you are able to find it quickly (and you should keep in mind that this material must be used only for this purpose in order this trick to work).
Then, in the options of the Solidify Modifier find Material Index Offset which lets you assign a material to faces generated by modifier. Set it to the value of the material you just created. From the wiki:

Material Index Offset
Choose a different material to use for the new geometry; this is applied as an offset from the original material of the face from which it was solidified.

After the modifier is applied, you are left only to select one of the faces generated by modifier, and click Shift+G > Material. All the vertices with the same material will be selected and you can add them to vertex group.
If the modifier is already applied
It should help selecting all the loops around rims and using Select > Select Loop-Inner Region:


How to detect collision amongst concentric circles

Add a single collision mesh for the entire board, then calculate the distance to the centre to determine which ring was hit.


Glass casting shadows and not looking real

If you look at reference photos online, it does appear that glass casts a shadow of sorts.  What happens is that some areas are darker and some are lighter due to refraction and reflection.

In blender, it looks like the default settings don't allow the full amount of light through, so I ran a series of tests.  The scene is a simple drinking glass and a small area light.

I've raised Glossy and Transmission bounces to avoid any issues with total internal reflection a la this talk, but otherwise the first image is with the default settings.  You can see the shadow is very dark.  I unclamped Indirect Light and unchecking Filter Glossy both gave interesting results.  Doing both at the same time, however, seemed to be on the right track.
Here's a render at 100,000 samples.

And this, to me, does appear physically correct.  The downside is that it takes a lot of samples for cycles to fill in an area with light.  Denoising works to cut down the samples required, but it still helps to run a higher number of samples to get clearer refraction effects.
I  pulled the light in to get some more dramatic effects.  Here's a glass Suzanne at 1000 samples denoised.

And here's the same Suzanne along with some other examples at 5000 samples denoised.  If you were wondering if the Glass BSDF and Principled BSDF gave different results, they don't appear to.

That and the next hexagonal prism are examples of how adaptive sampling can work against you.  Here are a few renders at 100,000 samples denoised.

I'm legitimately impressed at Cycles' results here, it's actually quite nice if you're willing to give it the time.  If you're unable to do that, you need to fake it.
You've tried one of the popular workarounds which is a Transparent BSDF on Shadow Ray.  I applied it to the glass panes in this test scene just for fun, but when I did I ran into a problem that you might be running into.

As you can see the shadow on the final pane is much darker.   Since we introduced transparency, we must raise the number of transparency bounces a bit.  I have 5 planes here, so 10 was enough for me.

When you use this shader to approximate glass, you can control how much shadow displays by changing the Value of the Transparent BSDF's Color.  I found that a value of .9 to .95 is pretty close.

Just to wrap up, I should explain why the default settings are the way they are.  Prior to all these settings, a really common complaint was that any glass added a lot of noise to the scene.  These would eventually resolve into those light rays, but the fix at the time was just to disable caustics.
The blender developers added these settings to clamp the light added to the scene, but unfortunately this has caused an issue for your use.


The impression of smooth edges is due to enabled Smooth shading. If you wanna to have sharp edges and smooth shading still active, add Edge Split modifier to the object.


As far as the Start-Up File, save a version as you like it in the older version and open it in the newer version and set it as the start-up file. You find that in the File menu by selecting "Save Start-Up File..."

I don't know about the User Preferences as I have the same question myself.


How to delete all animation from an appended file?

Is is possible the channels are locked / protected?

You can click the lock icon to toggle this, or press Tab while your cursor is hovering over the channel.


Convert Blend file to GLTF with baked materials

The preferred material setup is described in the Blender glTF addon docs. You can use a process like How do I bake a texture using Cycles bake to bake a diffuse texture (or other things) which are compatible with that setup.


An edit mode solution is by using the Bisect tool. Check the Clear Outer option to delete all vertices above the intersection plane:


How to create Dict from Collection Property in Blender python?

If you don't need to write out default value, just use items() like dictionary.
Unless you assign it, Blender will not create an entry for them.
import bpy
import json

data = [
    prop.items()
    for prop in bpy.context.scene.favit
]

print(json.dumps(data))  # save this string to json file

output:
[[["index", 1], ["label", "hello world"]], [["label", "cool world"]]]

The output format is same as [key, value] in a list,
once you want to write back to blender,
json_string = '''[[["index", 1], ["label", "hello world"]], [["label", "cool world"]]]'''
data = json.loads(json_string)
for prop_list in data:
    prop = bpy.context.scene.favit.add()
    for key, value in prop_list:
        prop[key] = value


Help with being unable to select a specific object

The object could be inhibited from selection (arrow icon disabled in the outliner), but maybe currently outliner is also set to show only other scenes, or object types (ie: outliner is not set to "All scenes") so you don't see it, atm.


First apply an array modifier to the train tracks. With a distance set to one, this will make the rail segments touch, and iterate. Then, add a bezier curve. Select it, press tab to switch into edit mode, and then manipulate it to get a good shape. Apply a curve modifier to the rail, and set the object to be the bezier curve you created. The rail will curve to match your bezier curve. An invaluable resource in blender is the modifier encyclopedia on Andrew Price's website. Great tool for reference. Hope this helps!


One way you could work around this is by using the knife tool. this can cut the white squares around into triangles that can be used to make the material flow a little better. you can do this by pressing k and then cutting out the shape. This should make it so you can have a better looking object. If you need any help with any of these steps, just ask.


Why won't Evee open the selected material in compositing

You are mixing up some things here:

The node-based material definition process is not the same thing as "compositing". They share the feature of being node-based but they are not the same thing.

Since they are two separate things, Blender 2.8 split the editor into two: the "Compositing" editor and the "Shader Editor" (Eevee doesn't really matter here, this is an unrelated change).

The one that you find in the "Compositing" workspace is the compositing editor. The one you need is in the "Shading" workspace.

It is also in whatever workspace you want, if you select the editor type to be "Shader Editor".


Yes, this is possible using volumetrics:

Method 1:
Using a cube to scatter light emitted from a spot lamp.

Create a cube and give it a volume scatter material:

Add a spot lamp:

Method 2:
You could also fake this by modeling the cone, then using a volumetric gradient for the falloff:

It won't be as physically accurate or as flexible, but it will be less noisy:

Example .blend (for both methods)


How to use transparent texture in the GLSL shading mode in BGE?

First in Material tab enable Z Transparency and set Alpha to zero.

Then in the Material Texture you need to enable Alpha in Influence section.


How to put animated background to keyed video?

Enable "convert to premultiply" to show the top video/image over video/image.


When I select an object, it does not show it as selected

You have disabled the Show Overlays option (or shortcut AltShiftW):


Linking Opacity to Z coordinates in the compositor

The Camera Data node gives you the distance from the camera. You can then add a math node to adjust that to get the desired amount of transparency.


When you are in he camera view (numpad 0), you can either use the "lock camera to view" option in the right menu in the viewport (open with N).

or press Shift+F for a egoshooter-like camera control (WASD to move, Q and E to move up and down and tab to enable gravity and finally the mousewheel to control your speed). I think this is the best option for camera positioning.


Strange liquid in glass and thick glass behavior

Finally, I tried several things and I got a better result by reworking lighting and trying a new camera angle. I closed the space where my flask is, added windows, added a ceiling, and added a few area lights at the top. I also tweaked my colors and absorption values. I also separated the interface meshes (now, they aren't connected, but still in the same object).

Here is my result

And here is my CuSO4ToAir material (the only difference with the CuSO4ToGlass is the IOR)

I will mark this answer as solution, but I am still listening to a better solution if you have.


How to rotate bezier control point (viewport not updating)

Rotating the handles of bezier curves.

Running script in edit mode on default bez (blender 2.82)

There are some issues at play, eg what handle type you are using.  I have set the type of both to 'FREE'

For example, here is a script to rotate both handles of point 0 of bezier curve by 45 degrees about the local z axis passing through the coordinate point.

Running the script 8 times should see the handles return to initial position.

To rotate have used one of the methods outlined in https://blender.stackexchange.com/a/7603/15543 which is probably a better way to go for a "Procedural System" than operators.

import bpy
from mathutils import Matrix
from math import radians

ob = bpy.context.object
cu = ob.data
spline = cu.splines[0]
p = spline.bezier_points[0]

M = (Matrix.Translation(p.co) @
     Matrix.Rotation(radians(45), 4, 'Z') @
     Matrix.Translation(-p.co))

p.handle_left_type = 'FREE'
p.handle_right_type = 'FREE'

p.handle_left = M @ p.handle_left
p.handle_right = M @ p.handle_right

Running the script in 2.81 in either mode produces the desired result and updates in the UI.

If you are having issues recommend that you look for errors in the system console, or IMO better still, test in the python console.

# this one throws a syntax error
bpy.ops.transform.transform(
    mode='ROTATION',
    value=0.6
)
# or this one relies on settings for axis an pivot point, but does rotate
bpy.ops.transform.rotate(
    value=0.6
)


You need to use the Vector/Displacement node now - instead of feeding a value directly into the Displacement socket. This is due to how the Displacement socket functionality has changed at the more recent versions of Blender (it’s a vector now, rather than a scalar.

See here.


The requirements for GPU rendering are higher than the minimum requirements for running Blender.

  Supported Graphics Cards

  These requirements are for basic Blender operation, rendering using the GPU requires slightly different requirements.

The manual states that GCN second generation or later is required for GPU rendering. Graphics cards that do not meet that requirement will not be listed in the preferences.

  AMD OpenCL

  OpenCL is supported for GPU rendering with AMD graphics cards. Blender Supports graphics cards with GCN generation 2 and above. To make sure your GPU is supported, see the list of GCN generations with the GCN generation and supported graphics cards.

  AMD OpenCL GPU rendering is supported on Windows and Linux, but not on macOS.

Since the Radeon R9 280 has the GCN first generation architecture it's not supported for GPU rendering.


How to fix exterior faces Blender thinks are interior faces

When you have trouble with Normals, i would highly recommend the following.

Go in the Viewport Overlays and activate "Face Orientation"

You should now see red and blue overlay on your object (blue face direction should always point outwards, red the backside of faces and should only point inwards)
Go in Edit Mode and press A to select all
Press Shift+N to recalculate normals outside
If there are still red areas facing outwards you need to select them manually
Press Alt+N and Flip those Normals

Now the entire object should be blue and you can deactivate the "Face Orientation"
A little tip, add Flip and show Face Orientation to Quick Favorits per RMB
It's so helpfull to have at hand and saves a lot of time.

Important is that only selected faces will be affected by the normal operations.

Interior faces as the tooltip says are faces were all edges have more then 2 face users!

Means faces that cover holes where more geometry is hidden behind.

Here a little visual explanation about it:

It's obvious that there are faces hidden behind the middle one covering a hole.
I believe you may have generated overlapping faces that lie above/in front of others that are facing outwards.
Try saving the file incremental and then select those interior faces and hide them with H. Should those now hidden faces not affect the mesh, just press Alt+H to show them again and delete them with X, "Faces".


What is the most efficient way to paint a 3D Sculpture?

Use Vertex Paint mode to color the sculpt. To make the vertex colors renderable set the nodes as pictured below (add the Atribute node with the vertex color's name and use it as a Diffuse color). There are some limitations in this method though- you have the access to only few brushes (compared to the ones available in Texture Paint mode) and the sculpted mesh should be very dense if you want to paint some detailed strokes.


Select all and delete in outliner search results

Selecting in the outliner would mark its list items as selected but does not select the objects you want to remove. To select more than one object in the outliner you can Shift-LMB each object.

Instead you could select them by name in Object Mode Menu:Select / Select pattern, Type Camera.* (this omits the default camera) and press X.


Vertex weights and vertex indices for Blender Python API

Okay, after posting on the blender forums, I was able to find an answer. To add vertex weights to a mesh you have to do the following:

Create a Mesh
Create an Armature
Create a list of vertex groups (the index of the vertex group is the bone index)
Set the parent of the mesh to the Armature
Add an Armature modifier to the mesh (so it know to deform by vertex group)

The code is kind of long, but it's one function so hopefully it's easier to trace through that the entire import plugin.

# Create Armature

armature = bpy.data.armatures.new('Armature')
armature_object=bpy.data.objects.new('Armature_object', armature)
armature_object.show_x_ray=True
armature.show_names=True
armature.draw_type = "STICK"

bpy.context.scene.objects.link(armature_object)
bpy.context.scene.objects.active = armature_object
bpy.context.scene.update()

bpy.ops.object.mode_set(mode='EDIT')

print("Creating bones")

for bone in self.bones:
    id = bone['id']
    pid = bone['parent_id']
    mtx = bone['matrix']

    joint = armature.edit_bones.new("bone_%03d" % id)
    joint.head = Vector( (0,0,0) )

    if pid != -1:
        joint.parent = armature.edit_bones[pid]
        joint.head = joint.parent.tail

    tail = Vector( (mtx[12], mtx[14], mtx[13]) )
    joint.tail = joint.head + tail

# Create Mesh

bm = bmesh.new()
mesh = bpy.data.meshes.new('Mesh')

for vertex in self.verts:
    pos = vertex['pos']
    x = pos[0]
    y = pos[1]
    z = pos[2]
    vert = bm.verts.new( (x, z, y) )

bm.verts.ensure_lookup_table()

for group in self.faces:
    for i in range(0, group['faceCount']):
        a = bm.verts[group['indices'][i * 3 + 0]['index']]
        b = bm.verts[group['indices'][i * 3 + 1]['index']]
        c = bm.verts[group['indices'][i * 3 + 2]['index']]
        face = bm.faces.new( (a, b, c) )
        face.material_index = group['materialIndex']
        # face.loop bmloop sequence to add uv

bm.to_mesh(mesh)
bm.free()

mesh_object = bpy.data.objects.new('Mesh_Object', mesh)

# For Vertex Weights, first we create a group for each bone
for i in range(0, len(self.bones)):
    mesh_object.vertex_groups.new("bone_%03d" % i)

#Loop over all of the vertices
for vertex in self.verts:
    index = vertex['index']
    indices = vertex['indices']
    weights = vertex['weights']
    mesh_object.vertex_groups[indices[0]].add([index], 1.0, "REPLACE")

bpy.ops.object.mode_set(mode='OBJECT')

mesh_object.parent = armature_object
modifier = mesh_object.modifiers.new(type='ARMATURE', name="Armature")
modifier.object = armature_object

bpy.context.scene.objects.link(mesh_object)
bpy.context.scene.objects.active = mesh_object


I have been useing Archipack with 2.8 for a while. I mooved to 2.83 and it stopped working

I think the data structures have changed, and an object created in an older version of Blender is liable to cause problems. Try creating some small object from scratch and see if it behaves better.


Add a circle Shift+A

Reduce its verts down to 3 >> Enter

Tab to enter edit mode

F to fill the vertices with a face.

E to extrude to the length that you desire.


Locking vertices to rotate the object around them

When you use forward kinematics, moving the body will move the arm and hand to follow the body motion.

When you use inverse kinematics (IK) the hand can be positioned and will stay stationary while moving the body. Note that a hand using IK will normally pull away from the location if the length of the arm doesn't reach the location desired.

By animating only clive's body you can see that the hand using IK stays still while the hand using FK moves with the body.

If you enable the rigify addon, you can add a meta rig and generate the final rig to get an armature that has IK/FK controls that you can look at. There are also many rigging tutorials that cover IK controls.


Booleans don't always work perfectly based on the geometry they are told to "cut" into. I hope there's not a specific reason you need the cylinder to be exactly there, because moving it a VERY small amount on the y axis before applying made it work for me. See below:


Exception_Stack_Overflow error in Command Line Script

Thanks for the help. As it turns out, the font I was using was overloading it. I erased all of the text, created a test file, and it rendered out just fine. Guess I will need to either find a different version of the same font, or find an entirely different font to use.


How do I make a sphere with 5 flat sides?

Another method:

Add a sphere (both types will work).
Add a cylinder with five verts:

Add a boolean modifier to the sphere and select the cylinder as the object:

Scaling the cylinder on the X and Y (SShiftZ) axes will change the radii of the flatten areas.
Apply the modifier and select the flat faces (the fastest was is probably by selecting one and pressing ShiftG> Area):

Press AltP and the select the center vertices:

Scale the vertices out (S). Then optionally set shading to smooth and add an edge split modifier:


How would I make gun animations for guns with multiple swappable parts

Switching out parts isn't an animation issue. You would do that through code. You rig your weapon and create bones or sockets for attachments and then in game you program it so that the attachments you imported separately from the gun get snapped to the right bone or socket.


How do I seperate shared vertices when creating seams for UV unwrapping?

Maybe switch the selection mode to Shared Location, it will take the seam into account:


Is there any tutorial on creating a slideshow with transition and with images of different sizes all done from python script?

Based on a concept tutorial that i made there is this addon from hapit at blenderartists forums http://blenderartists.org/forum/showthread.php?360518-Addon-Dynamic-Slideshow basically you use the inport images as planes then place an animated camera over each image. This animation is editable per camera and occurs simultaneously in the scene.  Then in the vse each camera gets its own strip to mix as tou like. This allows you to rearrange the order of playback easily.

The main point here is retaining the full image resolution which the vse cannot do as it always conforms source to project dimensions or crops at 1:1.


According to the documentation the strength value of the node should be in Watts, but this doesn't seem to be correct from experimentation.  The empirical behaviour of this seems to be as a multiplier.  So if you have a 1000W light and the strength set to 0.5 then you should have the effect of a 500W light.

Regarding color it is important that you set your light color to white if you intend to set the color of the node, this works in much the same way.

Concretely, it appears that nodes filter/amplify the light itself.  You can check this by setting you light power to 0W, no matter what you set the node values to, do you'll not produce any light.

I'm not sure what the intended behaviour is, but playing around with it suggests that a white emission shader of strength 1.0 will produce light exactly as it is configured in the light properties panel.

So the answer to your question is both can be used, it is up to you to decide if it is necessary to use nodes at all for this and just set the properties on the area light as you would expect.

Scale will matter as this defines the falloff of the light, however if you change the scale, blender will automatically compensate by changing the power level of the light.  So if you set everything up and then change the scale you shouldn't notice any difference unless you look at the power property of the light.


Confusing problem when I'm trying to mix Diffuse with Glossy shader

The problem appears to be that you're trying to apply techniques common to older raytracing software like Blender Internal to a physically-based rendering engine - cycles in this case.

It's a real problem if you come from a world of specular maps, shadow maps, bump maps, displacement maps and so on.

Some of these maps are simply there to help the fake the look of objects in the real world. Indeed, I use maps in my own ubershader which allow me to include metals, paints, glass and even holdouts all in a single (albeit complicated) map image.

It's really hard to wrap your head around physically-based rendering, but once it clicks, you won't want to go back to the old methods.

For basic specularity the following:

The two shaders - diffuse (also called albedo) which is your colour and only the colours.
A mix shader to make sure that the light leaving the scene does not exceed the amount of light entering it.
A fresnel node to keep the mix looking as it should.

Try a setup like this:

and experiment with the IOR value in the fresnel node: values below 1 are not physically accurate and values above 2 are getting outside of a reasonable range too - but you can use them if you like the effect!

That's really all there is to it. You can feed the colour input of the diffuse node with your image and let Cycles do the rest.

If you're doing metallic objects, remember that they don't have any colour of their own (by and large) and get everything from their environment. There are a few exceptions like gold, but metals are so hard that pretty much all light bounces right off them. There are also fresnel effects for a very few metals such that the fringe around the object (a sphere is great for experimenting on) changes colour.

You can see these effects here. An IOR of 1.25 gives a nice effect (and is reasonable for objects like this but as we push it higher you can see how the light appears to creep around the edges. When I push it to ridiculous levels (5 in the example) you can see the entire surface looks unreal.

One area where you might want to use a specular map (or at least, the equivalent) is where you have a wet surface such as a road with puddles. The puddles are reflective and the road is a dielectric (a fancy word for non-metal).

I get around this using the fact that the colour in real-life is limited so that no colour should be darker than 20% or brighter than 80% (0.2 to 0.8 in your Cycles engine.)

This allows you to cheat by putting areas of 100% white or 100% black on the image and then filtering using a value node to switch to a different shader group.

Here's a simple node setup - not that where I've used a chequer texture to make the effect visible, you'd plug in your albedo/specular map and area that's 100% black or very dark using these values, gets the glossy treatment. I left the fresnel out of this to keep the node setup cleaner.

and the result:


Making an addon, how do I pass information between a UI panel button press and my custom operator?

You can just add a property to your operator class.

This is done by inserting a line between the class declaration and the class methods.  Both bl_idname and bl_label are properties, these are inherited from bpy.types.Operator.

So lets say you want to add a property to an operator that prints monkey names.  The property will be called my_monkey:

class Monkey_OT_Operator(bpy.types.Operator):
    bl_idname = "wm.print_mokey_name"
    bl_label = "Print the name of my monkey"

    # 2.7x way to add a string property to hold the monkey name
    # my_monkey = bpy.props.StringProperty()

    # 2.8x way to add a string property
    my_monkey : bpy.props.StringProperty(name="My monkey name")

    def execute(self, context):
        print(self.my_monkey)
        return {'FINISHED'}

Okay so this should seem pretty simple, we've added a "slot" into the monkey operator class that holds a string.

Now to use this in your panel layout you can just set the property as you would for any normal class, for this you need a reference to your operator:

    row = layout.row()
    op = row.operator('wm.print_mokey_name', text = "Print Monkey")
    op.my_monkey = 'Suzanne'

Now when you print the button, it should print Suzanne.

Of course, you are not limited to string properties, you will find a more comprehensive use of properties in the Blender API documentation - Properties


How can I roll a cube (around its edges) with armatures?

This is just what you need! This is a Wolfram Alpha widget that showe you the cylogons (roulletes on n-gons about a straight line). The square is a default option:

http://demonstrations.wolfram.com/TracingACyclogonRouletteOfAPolygonRollingAlongALine/

EDIT: I made a canned animation of this rolling motion here, maybe you can use it:

http://pasteall.org/blend/index.php?id=51926


Why dont I see my texture on the object?

In cycles you to create materials using shaders.

Select the faces you want to use those materials, and assign the material to them with the assign button.

The image needs to be used as a texture by the shader using the mapping you've set up on the Texture coordinates.


Go into the compositor, and add an Add > Distort > Scale node.


Fluid Sim Liquid Domain is bigger then the area I dedicated to it

A fluid domain will always enlarge around the mesh to be a world-space referenced bounding box (@Gorgious commented), so what you could do to avoid extra voxels is:

Rotate the fluid sim with the domain in the same orientation as the world.
Run and bake the fluid sim to mesh.
Re-rotate the sim back into the desired position.


Try Joining the Meshes Before Parenting to Rigify

The reason why parenting may not have worked is because your mesh is in multiple parts.

Joining the meshes together before parenting to the rig should fix your problem.

For your cyclops file, here's what I did:

Select one mesh, press 'SHIFT+G' choose 'type'

Join your meshes. 'CTRL+J'

Press 'Tab' to go to edit mode

Remove doubles. press 'A' until everything is selected > 'W' > 'remove doubles'

Delete all vertex groups from the vertex groups panel

Delete all armature modifiers from the modifier in modifier panel

Select your armature and set it to pose mode. CTRL + tab

Select the mesh, then the armature, press CTRL+P, choose 'automatic weights'

Now your mesh should deform when you pose the armature in pose mode.

If and when you edit the weight values for each bone/vertex group, the deformation bones are on layer 29 of the bone layers ( not the regular layers )

Good Luck

Btw, cool model, where is it from?

Here's a link to your working file:

Here's a general video about setting up rigify in general :

https://www.youtube.com/watch?v=dYiAd_08-0k&t=140s


Sculptris seems to mess a bit with custom split normals data (or the export routines at least). When Custom Normals are present, some functions of Blender won't give you the expected result (and recalculating the normals is one of them, as well as setting an Edge Split ange). Delete this data to free the normals again. You can do this in the Mesh Data tab using the Clear Custom Split Normals Data button:

After this, all normals are pointing in the same direction again:
before

after

finally, recalculate the normals using Ctrl + N:


Move CENTER (not pivot) to SELECTED array of (edges, vertex, faces)

Bmesh version

The origin is local coordinate (0, 0, 0)

In local (vertex) space the selected location vector o is the average of selected vert coordinates   Make that the origin point by subtracting vector o from all verts' coordinates.

Then move the object to counter the shift in local coords.  The vector t  is the equivalent global space translation, of local space translation o.

Test script. Edit mode. Select verts, run script.

import bpy
import bmesh
from mathutils import Vector, Matrix
context = bpy.context
ob = context.object
me = ob.data

bm = bmesh.from_edit_mesh(me)
selected_verts = [v.co for v in bm.verts if v.select]
# average of selected verts
o = sum(selected_verts, Vector()) / len(selected_verts)
# make this the new origin
for v in bm.verts:
    v.co -= o
# move the object

mw = ob.matrix_world
t = mw * o - mw * Vector()
mw.translation += t

bmesh.update_edit_mesh(me)
me.update()


How to achieve vapor or steam effect with smoke sim?

Result:

Basic setup:

Change Blender units to Metric.

Create Circle (Shift + A > Mesh > Circle) with 2cm Radius and Fill Type > Ngon.
Press Space and type in "Quick Smoke". Select it.
Position domain as in the picture:

Change Light Paths > Volume to 2. It will allow light go trough smoke thus it could be white.

Smoke Domain:

Change Resolution to 64. Higher resolution = more details.
Behavior > Temp to 0.4. Smoke will rise higher.
Behavior > Vorticity to 4. Smoke will have more 'wrinkles'.
Check Smoke Adaptive Domain.
Check Smoke High Resolution and change Noise Method > Strenght to 1.

Material:

Use this node setup:

You can control smoke density by changing Multiply value.

Final thoughts and .blend file:

You can play with Resolution and/or Smoke High Resolution Divisions to get more detailed smoke.

You should save your file and change Smoke Cache to OpenVDB > Float (half) it will speed up whole setup.

To play animation hit ALT + A or first Bake it under Smoke Cache.

Note that I'm using HDRI for lighting, it is packed in .blend file.


Rendered soft body physics animation doesn't match viewport

This problem should have been fixed in the 2.83 version.

Report Link: https://developer.blender.org/rBfe5933a972e15656bdfa1af9eaa0cf64619c9425


Modeling a character with its arms by its side can cause issues at two stages. While modeling or sculpting having two disconnected parts together can make selecting and moving each part separately harder. Then while rigging the character, it can make it harder to specify which parts follow each bone.

Whether you model a character with arms straight out or half way down is mostly a matter of taste, each helps the modeling/rigging process. Some people suggest the more relaxed pose is better as the mesh is closer to the normal position so there is less stretching around the shoulder.

As for drawing a modeling sheet, draw them in the position to be modeled. It's not uncommon to have the side view of a character with the arms moved to the side to keep the drawing clearer to read. You may be interested in this CGCookie tutorial on drawing a modeling sheet


Blender's "View Animation Ctrl F11" shows purple (missing image) background instead of transparency in 2.83 / 2.90

This might be a bug. In the latest build this doesn't happen anymore.


At first glance, there are multiple reasons why your rig could be bending sharply, but if you try moving the upper arm, things should become a little clearer.

Your model has weird bends because of your automatic bone envelopes rig.

The vertices in the range of the bone envelope need to slightly affect the vertices outside of the envelope as well, producing a falloff.

You are using a modifier with automatic bone envelopes, so you will have to manually weight-paint the bone influences, or assign vertices manually with vertex group rigging.

It is going to be tedious due to the sheer number of vertices your model has. However, you can make rigging easier for yourself in the future by following a very important rule: BE CAREFUL WHEN APPLYING SUBDIVISION SURFACE MODIFIERS.

Applying a subdivision surface modifier is destructive and cannot be reverted. You will have to make your 3D model from scratch if you are unable to weight paint every single vertex to each bone or use the vertex group method.

The cubes in the top image are all the same model; the desired result has an un-applied subdivision surface modifier, and the sharp bend result has an applied subdivision surface modifier. It is better to work with un-applied subdivision surface modifiers since there are less vertices to select and navigate around when rigging manually, which you will have to do to fix your rig.

Automatic rigging options, such as the checkbox in the armature modifier, or parenting a mesh to an armature with automatic weights, sadly, do not always work.


Animation Nodes - How to make text creep up?

Offset the scale of characters based on an inverse delay falloff as follows:

The little bounce can be achieved by changing the delay interpolation into a back one:


Minecraft animation, uploading a minecraft skin

You need to go to Object material properties>UV maps. The images will show you what to do (make sure you have the body of the character selected):

Do the same for the head and you are done!


Rendering high poly to low poly normals. UV are out of bounds

What you're seeing is due to the Margin setting found in the Bake panel. Basically it causes the color to extend a set distance past the UV island boundaries. So your actual bake should have turned out fine. I think the purpose of the Margin setting is to ensure that the UV islands never extend past the baked texture.


Converting texture files in blender using Python

Okay, I figured it out.

image = bpy.data.images.load("filepath_to_source")
image.file_format = "TARGA"
image.save_render(<filepath_to_destination>)

I tried using image.save() function before I posted this question, which raised a Runtime Error:

  Image does not have any image data

and I thought I was doing something wrong. Using save_render() function seem to have fixed it. I still don't know why save() didn't/doesn't work.


Your computer needs to save every single particle position, rotation, scale, physics, etc. in order to properly display them. For a single particle, this isn't much- but it adds up, especially with thousands of them.


Rendering only the highlights of an object in Cycles

You can emulate equivalent results with Cycles Ray Visibility flags for the lamp object.

To a similar result to highlights you can turn off all components except Glossy for your lamp object.

Have in mind that this will only work on objects with materials with some sort of glossy reflection component. Purely diffuse, transparent, refractive or translucent materials will likely become totally unaffected by that light siurce


How to know which side of a face is being rendered?

You need 2 vectors for calculating this:

A = the face normal
B = a vector pointing from camera to the face center (face.calc_center_median(), = point of face normal origin)

You get both from the python API from mesh or bmesh data and from Camera object location.

Then you calculate a Dot product between these 2:

from mathutils import Vector

C = A.dot(B)

if the dot product is negative, the vectors point towards each other (face is oriented towards the camera)
if the dot product is 0, the vectors are orthogonal and the face is not visible
if the dot product is positive, the vectors point in the same direction and you see the backface from camera

You can see how dot product works here: www.falstad.com/dotproduct/

Alternatively to solve this inside shaders you can use the Geometry node. In Cycles the socket is named Backfacing, in Blender Internal the socket is named Front/Back. You can have a material that chooses from 2 materials based on this mix factor. This approach will dynamically switch between materials even if the camera is animated, this does not happen if you assign materials with script and then during animation the camera angles change.


Is it possible to edit an animation built with Mixamo ?

You should export in Collada format from mixamo. When you import into blender, the animation should be editable.


Why is my model distorting when I weight paint?

This is because you have moved some of the bones while in pose mode. While weight painting you are changing how the vertices of the mesh are being influenced by the bones.

To fix this, select the armature and go to pose mode. Then select every bone and press alt+g and alt+r to reset the location and rotation of each bone respectively. (alt+s to reset scale)

Then with your mesh selected and in weight paint mode, you shouldn't see any more deforms while painting because the armature is in its default position.


The bones in a model is affecting another model

It sounds like both objects are parented to the same armature and/or are using the same armature object in the armature modifier. You will have to have a separate armature for each model. You should be able to simply select the proper armature in the armature modifier as well as in the relations section of the object tab of the properties window.


Do EEVEE samples have any effect when rendering?

There are several things affected by EEVEE sampling, as you can see in this example scene, rendered at 1, 8 and 64 samples:

soft shadows are obtained by sampling large light sources using many small light sources. Low samples will "reveal" the point lights. This is generally the main downside of a low-sample rendering, therefore you should choose the number of samples based on how good your soft shadows look.
 top view:

the direction of refracted and reflected is also sampled because, especially around the corners, a sub-pixel change in the direction of the ray can make a difference between hitting an object, another object, or the sky. For low samples, this results in a strange pixelated blur

aliasing is what happens when a curved profile is drawn using pixels: it gets jagged if the pixels aren't "smoothed" (antialiased) adequately. More samples make the contours smoother.

[Added Sept 2020] the quality of Alpha Hashed transparency is also affected by the global sampling. Indeed, for each sample, a pixel will either be rendered as fully opaque or fully transparent: a fractional transparency is a result of averaging over multiple samples. With too few samples, tranparency appears patched/noisy:

[Added Sept 2020, suggested by Andrey Sokolov] the number of volumetric slices rendered depends on the EEVEE sampling: note how at 1 sample the dust cloud appears 2-dimensional.
PS There is another "Samples" count inside the Volumetric tab that controls the quality of each slice, and is independent of the global EEVEE sampling.


Is it possible to transport materials between the Internal render and Cycles render for animation?

Materials for blender internal have limited support for nodes, while cycles uses nodes only. The cycles nodes will not work for internal materials nor will internal nodes or material settings work with cycles.

You can create a material that has both nodes in it. There are some nodes that are common to both and can be interlinked with each other.

What this means is you cannot use the same nodes for both render engines, but you can integrate two node setups into one material so that one material can be used for both render engines.

For a simple material that uses an image texture and a diffuse node this will be a simple task. For more complex materials you may find it hard to get the two to match up.

As an example you could look at the materials used in CGCookies Flexrig, the materials there are deliberately created to work with both render engines.

While not large enough to be very clear this is one of the materials in the Flexrig, The red and green frames are cycles nodes while the darker section at the bottom is for BI. The purple section is common values used in both node setups. The cycles nodes appears simpler because they are groups.


array modifier to build a virtual pipe organ? or should I look for scriptwriter?

There are lots of parts and variables to your question.

You could easily create the organ pipes in Blender and use the array modifier to place it in your scene. The array modifier allows for some degree of variation between instances, like scale rotation, position, but it is limited in scope, and for more freedom between each arrayed tube you are probably advised to use non-arrayed duplicate clones of each object.
You could then scale each part individually and space it properly without affecting all other objects.

Blender has no hyperlinking functions built in, and what you are looking for is some sort of interactivity like a real time demo or application. The way I see it you could achieve this in a few different ways, but this is a really broad area with many different possible approaches and probably out of scope for this site.

The most basic way would be to render out an image of your organ pipes, and build some sort of image map or clickable interface layed out on top of it, possibly using either HTML+CSS or SVG or some other technology to your liking.
Use blender's built game engine and create a simple game application that consists of some basic logic that reacts to clicking the pipes and playing the corresponding sound.
Use Blend4Web which is an addon for Blender that allows to create interactive WebGL based applications with some basic interactivity options and create a web based demo that reacts and plays sounds when clicked on certain objects.


Can a local axis be aligned with an edge?

Yes, you can have any number of custom transform orientations. You create a transform orientation by selecting either a vertex, edge or face and in the Tool Properties panel (N) at the bottom, expand the Transform Orientations tab. The plus sign will add a new orientation based on the currently selected element in the scene.

It's a good idea to name these orientations if you plan to reuse them, else that list can get confusing.

This Transform orientation can then be selected from the drop downs in that same panel, or in the 3dView header. Because they persist in the .blend they can be recalled at any later stage.

Also see this answer, which covers much of the same

Limitations

(Dec 2015) You can't make a Transform Orientation using a Curve Object's Point or Segment.


Set resolution of curve generated with Animation Nodes

you can change the visibility of some inputs in the properties shelf (press N in the Node Editor).

select the curve object output node and check the eye icon for preview resolution. you can now set the resolution in the node itself


How to create an edge between 2 selected edges?

In Edge Mode, select the two edges you want to connect, and W > Subdivide, (or  W S).

If you're looking for an effect similar to the 3DS  'Pinch' and'Slide' you can get somewhere near by connecting edges as described with one cut, selecting it, and using CtrlShiftR (Offset Edge Slide) for the pinch, and an ordinary GG for the slide, Not quite as flexible, there's an extra edge in the way.. but it's quick.

As always, it's worth checking out the options for these operators in the tool region.


Can Grease Pencil work with 3D Scene/Objects in Viewport for Grease Pencil?

Yes. Grease pencil objects exist in 3d space so they can be used in scenes together with traditionally modelled 3d objects.

This video shows regular 3d models being used as a reference in a 2d animated scene: https://vimeo.com/164067136


Select the bones to switch and press [CTRL] + [R]. Select the preferred rotation mode.


Is there a low level alternative for bpy.ops.object.convert()?

The to_mesh method

import bpy

context = bpy.context
scene = context.scene

mball = bpy.data.objects.get("Mball")

if mball:
    me = mball.to_mesh(scene, False, 'PREVIEW')

    # add an object
    o = bpy.data.objects.new("MBallMesh", me)
    scene.objects.link(o)
    o.matrix_world = mball.matrix_world

    # not keep original
    scene.objects.unlink(mball)


You can change the theme from dark to light in the preferences. Open Edit > Preferences then go to Themes and select Light from the dropdown. The dark theme is the default in Blender 2.8.


How to get full file path to rendered image?

There's a utility function:

  frame_path()
  RenderSettings.frame_path(frame=1)
  Return the absolute path to the filename to be written for a given frame

scene = bpy.context.scene
path = scene.render.frame_path(scene.frame_current)


From my experience it seams, that when using boolean you should always make ends of hole cutting mesh, stick out of the mesh, that is being cut. So in this instance you have to go to edit mod and raise up top vertices of bolts, above surface of window clip and lower bottom vertices of bolts below surface of window clip. This will solve the problem.
p.s.
By bolts I mean cutouts, lift nuts and cutouts, glue plugs


Rendering task are more complicated then CPU and GPU usage graph show.

When Blender encounter a bottle neck, sometime it is not the multi-threading task like rendering tiles but a calculation in a single process thread.

And some time because the RAM speed isn't fully catch up with CPU and GPU, or sometime some I/O waiting of hardware is locking the process.

It is hard to tell what is the bottle neck from the scene, especially you just show a task manager image with low resolution. From your graph, the RAM is actually drop for a large amount during the processing. I would guess that Blender is dealing with quite large of detail from your scene, and the thing dealing in Blender is often single python thread which can't not benefit from multi-core CPU.

For speed up the rendering, there are a bunch of option in performance panel, you can try to render single image to see the speed difference.


You can use the "Object" output of the Texture Coordinate node, together with the "Rings" type wave texture.


I updated my Blender from 2.8 to 2.81a. That fixed my problem, therefore it must have been a bug.


Try this: Extrude your outline to create a "flat topped" shape.

Switch to a side view and create a curve that describes the peak at the "stroke cross" the way you're visualizing.

Extrude your profile view curve along the horizontal axis to create a shape that intersects and contains your logo.

Boolean intersect.


Physical simulation of multiple scenes simultaneously

It's not possible. The active scene (bpy.context.active_scene, I think) is shared by the whole blender session.

You could within one scene use several viewports without a problem (check the manual, you click and drag from the \\ section in the lower left corner to create a new viewport and set it to '3d view').

If what you want is a final render with a 3x3 matrix you could render them from separate scenes and merge them using the compositor in a new scene (using translations to move them and scale them to put them at different places on screen).


The problem is caused by a small discrepancy between how the booleans are applied on a level 3 subdiv and a level 4 subdiv. Drop your render sub-div level down to 3 or move the torii so they create the correct behaviour with level 4 subdiv enabled in viewport.


When I import an OBJ it won't show up, does anybody know how to fix it?

For me at times, .obj files have imported super huge or super small. It might still be there but out of view. Try selecting it in outliner window in upper right and then in the 3D window hit . on your numpad or choose View > Selection in Object Mode.


Go to the Properties panel > Object modifiers tab (wrench) and add an Edge Split modifier. Adjust the value until it looks right. This will get rid of the "deformed and no longer look real" edges.

Note that this works with Smooth shading enabled like you had.

Progression of the Edge Split modifier (Image from the Blender Reference Manual):

Edit:

What I did produced the following result. Note that I was unsure exactly what color you wanted, so I chose a medium-light red. I edited the material as well to get rid of the Volume Absorbtion. Change the color through the Glass BSDF color settings.

Render result:

Material settings:

I did the following for the cup and sleve meshes. I started by keying Tab to enter Edit Mode, A once or twice to select everyting, and Alt + J to convert the majority of the triangular faces into quads. Read more about that in How do I convert a triangle mesh to a quads one?.

I then turned the Edge Split modifier up to a Split Angle: of 30. There are still some imperfections, but from the camera's distance, they really don't show. Those are just down to the mesh and the modeler, who designed a mesh with awful topology.

I was able to do something about the water. This is a good lesson: If you are going to have water, unless it's a fluid simulation, have the water be part of the cup. What I mean by this is that instead of having an alternate water object, one should add a second material to the cup following the steps outlined in Add different materials to different parts of a mesh?.
I changed the viewport color for increased clarity. I would go over how I selected the inside of the cup, but it really would take forever.

Viewport coloring:

A coke bottle that I made where the glass is also colored instead of having a separate liquid mesh inside:

The noise is down to optimizing the Light Paths settings, upping the samples, changing the Filter Glossy, and Clamping Indirectly. I also upped the lamp and world lighting. Read about many good ways to reduce noise and optimize a render in these two BlenderGuru articles:
7 Ways to Get Rid of Fireflies Once and For All
4 Easy Ways to Speed Up Cycles
Check out the settings here to see what I did:

Some of the Tris to Quads magic reduced the file to 30 mb so Blend Exchange, here I came! Note that I split the objects into 3 layers so I could play with them easier. Lastly, if the .blend file does not render clear enough for you, just keep upping the Render Samples: until it does. :)


Blender 2.8 and Google Earth Studio (GES) 3D camera integration/import

I actually just solved this problem a few seconds ago for myself after I found AE2Blend:

https://blendermarket.com/products/ae2blend
($10)

After installing the add-on in blender, I ran the script from Google Earth Studio inside AE and then literally copied and pasted the keyframes into Blender.  Couldn't be easier.

Only issue I'm facing right now is that I animated the Camera Target in GES and that effs up your camera in AE, so I'm currently looking for a solution for this before I have to reanimate.

Good luck!

Gonzalo


Baking displacement map: Base mesh is included in the highres output

Answer from @Secrop on blenderartist.org:

  Add a subdivision modifier to the low poly object before baking.

  The thing here is that each poly in the lowres object is flat, but the surface from > the highres is curved… This makes the displacement value at the center of those polys to be greater than their corners.
  If your lowres is later to be subdivided with ‘Simple’ method, this bake will be correct. On the other hand, if you use ‘Catmull-Clark’, then you need to use this subdivision at the baking phase also.

Result:


Where is emission color in Cycles Render Engine

In Cycles Render you find the emissive material by
a) > Properties Editor > Material > Surface > Use Nodes > Surface Emission or more easily:
b) within the Node Editor by > Shift+A > Shader > Emission. Connect this to the Surface input of the Material Output node.

Or give this Add-On a try:
https://wiki.blender.org/index.php/Extensions:2.6/Py/Scripts/Material/Blender_Cycles_Materials_Converter


If there are no links you will get indexerror, so I would rewrite your last three strings of code:

for mat in bpy.data.materials:
    mat_node = mat.node_tree.nodes
    for node in mat_node:
        if node.name == "Principled BSDF":
            for link in node.inputs[0].links:
                mat.node_tree.links.remove(link)


Understand how to make EXTREMELY large objects if i should?

After comments and talking to people I realized that i shouldnt actually make something that large. when im making a scene just make it look larger than it is and when its in game make it so they dont realize isnt completely made


They are not loops anymore. You can check that by pressing Alt+Shiht+Click.

You would have to reconnect the corners (Snap these vertices to edge and Merge by distance or Merge (M) by Last) ...

And then select those edges and Delete (X) Disolve edges.

But I would rather keep these loops because of very spiky shape of face.