Is it possible to create an incremental array?

Here you go!

Keywords: Number Array Watch Dial

import bpy

from bpy.props import IntProperty,FloatProperty

class NumberArray(bpy.types.Operator):
    """Add a simple box mesh"""
    bl_idname = "mesh.primitive_number_array"
    bl_label = "Add Number Array"
    bl_options = {'REGISTER', 'UNDO'}

    start = IntProperty(name="Start",description="Start value",min=0, max=100,default=1 )
    count = IntProperty(name="Count",description="Number of items to create",min=1, max=100, default=1  )
    offset = FloatProperty(name="Offset",description="Distance",min=0.01, max=100.0, default=1.0 )

    def execute(self, context):
        x = 0.0
        pos = self.start
        end = self.count + self.start
        print(context)
        while pos < end:
            bpy.ops.object.text_add(view_align=False, enter_editmode=False, location=(x, 0, 0), layers=(True, False, False, False, False, False, False, False, False, False, False, False, False, False, False, False, False, False, False, False))
            ob=bpy.context.object
            ob.data.body = str(pos)
            x = x + self.offset
            pos = pos +1
        return {'FINISHED'}

def menu_func(self, context):
    self.layout.operator(NumberArray.bl_idname, icon='MESH_CUBE')

def register():
    bpy.utils.register_class(NumberArray)
    bpy.types.INFO_MT_mesh_add.append(menu_func)

def unregister():
    bpy.utils.unregister_class(NumberArray)
    bpy.types.INFO_MT_mesh_add.remove(menu_func)

if __name__ == "__main__":
    register()

Updated (works with 2.74):

https://github.com/3dbug/blender

Run the script in Object Mode by Add / Curve / Create Dials and Scales.


Open the System Preferences (ctrl+Alt+U) and in the addon section enable the Import Lightwave Objects Addon

An option to import LWO will appear on the file menu.


If animation is 40 frames, should I cut it off at 39?

In short, yes. Frame 40 does count as a frame, unless you specifically tell the timeline or NLA editor to ignore it.


If you want to do this in real-time, I would investigate using UDP sockets, as they're fast and cheap.

As a test I created a modal operator who was on a timer and listened on a socket on each cycle.

Unfortunately, my modal operator arbitrarily appears to just stop. But as a quick test, this looks promising.

Create a cube. Start this python client (who sends random data).

import socket
import random
import time

UDP_IP = "127.0.0.1"
UDP_PORT = 5006

print("UDP target IP:", UDP_IP)
print("UDP target port:", UDP_PORT)

sock = socket.socket(socket.AF_INET, # Internet
                     socket.SOCK_DGRAM) # UDP
sock.connect((UDP_IP, UDP_PORT))

for i in range(1000):
    time.sleep(0.02)
    MESSAGE = str(random.randint(0, 5))
    sock.send(MESSAGE.encode())
    print(MESSAGE)

And run this modal operator in Blender.

import bpy
import socket

class ModalOperator(bpy.types.Operator):
    bl_idname = "object.modal_operator"
    bl_label = "Simple Modal Operator"

    def modal (self, context, event):
        if event.type == 'ESC':
            context.window_manager.event_timer_remove(self._timer)
            return {'CANCELLED'}

        if event.type == 'TIMER_REPORT':
            try:
                data, addr = self.sock.recvfrom(1024)
                self.cube.location.x = float(data)
            except:
                # timed out
                pass

        wm = context.window_manager
        self._timer = wm.event_timer_add(0.2)
        return {"PASS_THROUGH"}

    def execute(self, context):
        self.cube = bpy.data.objects['Cube']

        print("creating socket")
        self.sock = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)
        self.sock.bind(("127.0.0.1", 5006))
        self.sock.settimeout(0.18)

        print("adding timer")
        wm = context.window_manager
        self._timer = wm.event_timer_add(0.2)
        wm.modal_handler_add(self)
        return {"RUNNING_MODAL"}

bpy.utils.register_class(ModalOperator)

bpy.ops.object.modal_operator('INVOKE_DEFAULT')


You can go into the Node View and use different nodes like Coloramp etc to change characteristics of your texture. These can be bound to keyframes in your animation.


You can try using the follow script

http://wiki.blender.org/index.php/Extensions:2.6/Py/Scripts/3D_interaction/Materials_Utils

I hope that script be of help for you


Boolean modifier works with volumes, It will not work with 2D shapes, flat forms, one-sided geometry.

So first, you need to add some volume to your object:

So, I guess, you have a trouble with proportional editing is on, turn it off by pressing O and move one face up to make a volume. And select all and press Ctrl+ N just to make sure, that normals are correct.

Then edit a ring. Remove central faces inside the ring and add 2 face on top and the bottom like this:

This makes you boolean works.


Blender includes an add-on to generate trees - try searching for Blender Sapling add-on Tutorial. This will add a new Curve option to allow you to create and configure a Sapling (there are multiple pages of settings in the Toolshelf after you Add the sapling).

For the "sunlight rays", look into Volumetrics.


HDRi not showing up in render, evee or cycles

To make the HDRI work properly you would have to use an Environment Texture node and you are currently using an Image Texture node, just swap them out:


VSE: One video overlays another - bottom one plays as expected, top one does not

Make sure your footages are conformed to identical frame rates. You will, for example, almost never find any North American device that will record at a flat 24, 50, 60, etc. and the actual value will be 24000/1001, 50000/1001, 60000/1001 etc. Assert that your framerates are identical, if they are not, you will need to conform them to identical rates, with the below caveat.
Conform to a motion picture codec that uses only I frames, which represent a whole frame. The FFMPEG library behind the scenes will be calculating offsets into the overall time stamps, and this will yield wonky results when you are dealing with compressed codecs leaning heavily on groups of pictures, or GOPs. The only way to avoid this, and have your cuts match perfectly 1:1 is to enforce codecs that avoid those I and P frames.

Bluntly, for this sort of an application, Blender is a poor tool, as still image formats are going to be vastly more reliable. In the context of your particular project, still image formats seem outside the scope.

See Audio/Video out of sync in rendered video, but not in VSE for more information.


I would like to simulate spiky ocean waves from an old animated cartoon

Would this be close enough?

How it looks when animated:

The Ocean Modifier creates a pretty realistic wavy sea, and the Simple Deform modifier enhances the vertical component.


How to upload videos from Blender to Youtube (and other things)

There seem to be several problems in your project:

File format is not the right one for YouTube
The frame rate is set to 32767
The camera might be rotated by 90°

Regarding 1): You probably want to use FFmpeg video as output format, with the Container set to MPEG-4, Video Codec set to H.264 and Audio Codec to AAC. This will create a lossy compressed video file. This seems to be one of the standard configurations that YouTube recommends.

Regarding 2): The frame rate should likely be 24/25/30/60 fps depending on the speed of your animation and the desired output frame rate.

Regarding 3): It could be that your camera is rotated 90° or it's because another setting in the video export was causing the issue. Check in the viewport that the camera perspective is correct by pressing Numpad 0.


I'm not sure if you're asking how to assign multiple Materials to the same Mesh or how to split one Object into two.

If you just want to Split a Mesh into two, the easiest way is to select all faces you need, hit "P" and then click "By Selection".

To create a 2. Material go to the Materials Tab and hit the "+" icon. Select all  the faces you want to share this Material and then hit "Assign" in the Materials Tab.


Boolean - subtract multiple objects from one with only one boolean modifier

No, you can't input multiple objects into a single boolean modifier.

You can add as many boolean modifiers as you want though. Simply create multiple boolean modifiers with their respective object's input.

You can also join all objects into a single object and use that as the boolean input. E.g. you could duplicate your window, then merge it into the boolean input object by ⇧ Shift RMB selecting the input object (making it active) and pressing ⎈ CtrlJ to join them.

As you intend to speed up the process, I'd advise you to use the built-in BoolTools addon, which creates a shelf for assign boolean quickly.


What is the Ambient Color in the Blender Internal Renderer exactly?

Ambient Color: The Ambient color is a constant color added to the reflection model. Light sources are summed together and used in the calculation of the diffuse and specular part (See Phong reflection model for details)

phong reflection = diffuse + specular + ambient

Horizon Color: The color to use when the raytracer does not find any intersection for the primary ray (direct ray from the camera). It does not influence the shading at all. You can see this as a sort of background underneath your render.

Zenith: When using sky_blend the background will blend from the Horizon Color to the Zenith. This is done by the output pixel coordinate so the result will be the same for all camera angles and positions.

So the Horizon Color and Zenith, that generates the background, can be seen as an underlay.


How do I eliminate a harsh lighting issue on my cylindrical glossy model?

It appears that you are using a Subsurf modifier, and a flat many-edged face on the back. That would be called an N-Gon, and is highly frowned upon in Blender as it brings a host of issues into the picture. Quads (faces with 4 edges) are much prefered, as it they work best for almost all of the relevant calculations done by Blender.

This particular issue can be resolved by adding an edge-loop near the face on the back by pressing Ctrl+R


Was quick switch between mesh and armature removed in Blender 2.8?

You might be looking for Lock Object Modes, which you can find in the 3D View Menu:

This was indeed added as a feature. For animators it is a bit cumbersome if they have to precisely click each bone during animation phase, that's why the modes are locked by default.


I found a good solution after some tests. I used the boolean modifier and used the different settings. Like that, I can separate the parts, and can then delete
them.

The finished model could look like this:


Okay, I'm looking at your .blend now.

There isn't one easy "here's the problem!" sort of thing. It's more like a series of problems. So I will try to, while attempting to keep this as brief as possible, point out each of the problems I see with your material and try to help you get the effect I think you're aiming for.

(Nice zamboni, btw!)

The first thing is, this makes no sense:

Neither does this:

Do this instead:

Another no-no...

Do this to see your material:

Here is how you can combine two images using the alpha of a PNG:

One important thing to understand about both RGB and shader mix nodes is that when something is plugged into the Fac input any white image data is considered positive (or 1 if you like binary) and any black image data is considered negative (0). All shades of gray fall somewhere in between. If you know what a PNG's alpha channel looks like you can probably imagine how this is all working now. We have taken that grayscale channel and told Cycles we want that to factor a mix of colors or shaders instead of transparency. Another important thing to understand is that whatever is plugged into the upper socket is what will mask through as 0 and whatever is plugged into the lower socket will mask through as 1.

But wait, something's wrong...

There are no images in this .blend. Looks like you forgot to pack them before sharing. For the future, this can be done from File > External Data > Pack All Into .blend.

Let's look on Pixabay to see what image we might be able to substitute for a taillight...

A bright red magic mushroom! Perfect.

Pixabay image credit shout-out to "adege"

Make a transparent PNG, and we're up and running again.

(Providing transparent PNG below. Use responsibly.)

At this point you have all you need to show the decal on your material.

But since it is a light after all, let's take it a bit further.

Connect an Emission Shader like this so light will be emitted from only the non-transparent parts of the PNG:

And I saw you were trying to add some displacement with your original node setup, so let's add that back in the correct way.

I think you'll need to change the lighting in your scene before the bumps will be visible on your model, but you can see them in the material preview. Adjust the Noise Texture parameters to your liking. The Math Node (set to Multiply) tames the bump values.

Now everything is awesome!

Oh wait... the decal is upside-down.

We had better fix your UV map too.

Wow! That is one hell of a UV map.

Since you've already got the 2D Cursor in the right place and you have it set as your pivot point, we can just rotate this bad boy 180° and we'll be good to go.

Okay! And that concludes this answer. Phew! I think I broke a sweat writing this. Also experiencing some pupil dilation and my computer's display looks amazing; how odd. Anyway, good luck and happy blending!


Alpha datas are useful when you want to give transparency to an area of your material.

In the case of the Image Texture Alpha output, let say you have a PNG with a transparent background (0% alpha). Plug the Image Texture's Alpha output into the Alpha socket of the Principled (or into the Factor of a Mix Shader between a Diffuse and a Transparent shader), the alpha of your image will be recognized as the area that needs to be transparent.


What is the difference between a meta-object and a mesh

According to the Blender Manual:

  Meta objects are nothing more than mathematical formula that perform logical operations on one another (AND, OR), and that can be added and subtracted from each other. This method is also called Constructive Solid Geometry (CSG). Because of its mathematical nature, CSG uses little memory, but requires lots of processing power to compute.

In contrast, a mesh object is defined by Wikipedia as follows:

  A polygon mesh is a collection of vertices, edges and faces that defines the shape of a polyhedral object in 3D computer graphics and solid modeling. The faces usually consist of triangles (triangle mesh), quadrilaterals (quads), or other simple convex polygons (n-gons), since this simplifies rendering, but may also be more generally composed of concave polygons, or even polygons with holes

Also helpful to see the Wikipedia page on Metaballs to further compare the differences between the two, and see the history of the object outside of Blender.

To directly answer your question, a mesh cannot be calculated in the same way as a meta-object, because a mesh object is described as a collection of vertices, edges and faces defining the shape of the object, while a meta-object is only a mathematical formula doing the same.


You can also change the Resolution in Render Settings > Dimensions:

For this you probably want to increase the X resolution.

Notice

Note that you can't scale the camera up by adjusting these values, you will need to move the camera and/or change the Focal Length to zoom/scale the camera.

Adjust the Focal Length in Properties > Camera > Lens
The easiest way to zoom in/out with the camera is:

Enter Camera view (Numpad 0) and select the camera
Press GZZ to move the camera along the local Z axis.

By using a combination of the above techniques, you can place and scale the camera however you want.


How do I make the Particles and Curve Guide Work?

Simple Fix

With the Curve selected ... Click on Path Animation which is depicted below with the Yellow Arrow.  Fix with a Click.  This might seem unexpected to you.
Use the curve guide settings below.  There is a goal to help the OP achieve his/her desired visual. The OP can still specify the goal in the original question.
Change the Particles to a longer lifetime. Easier Visibility.  Later Change to your Artistic needs.

Path Animation Clicked. Curve Guide Works. Spiral not so obvious. Curve Guide Settings not to OP Artistic taste perhaps.  Image above.

Curve Guide to fulfill Artistic taste of OP. Spiral Very Obvious. See the settings in the Curve Guide Panel.   2 Images Above.

Change the lifetime of particles in the particle panel of the sphere. Image Above.

Notice the Circles magically appear on the ends of the curve. Image Above.

Particles in Ascencion.


How to Sculpt Toothpaste or Paint Coming Out of Tube?

just like this using a cube with dyntopo sculpting.


Set default UV Image Editor display mode

Open new file, clear that Render Result in the UV / Image editor window and save User Prefences. Note that the latter will overwrite previously saved settings so you might want to backup them first.


Looking to see if Blender is a good tool for an AI project

In my mind, blender is a good fit for this sort of project. It has access to python allowing high level development and the use of many many libraries.

  What I want to know is, does the Blender game engine/python library give access to a camera

Yes - you can extract the pixels from a camera using the ImageRender refresh() method by passing in a buffer and pixel format. I have used this for a variety of purposes in the past, though not for robotics.
https://docs.blender.org/api/blender_python_api_2_78a_release/bge.texture.html#bge.texture.ImageRender.refresh

  and stream its input in real time,

You'd have to set something up

  and is it possible to send motor sequences to a virtual arm?

Yes. I wrote a minimal test scaffold for a UR5 robot arm. This allowed me to test a program intended for the actual hardware without needing the actual arm present. This was a huge help when trying to do a university project with limited lab time. I also somewhat sidestepped the project (with permission) by writing a blender script to generate the proper commands from the virtual setup....

  just having access to the pixel buffer is enough using, more over a high resolution isn't required, 1024x768 is plenty.

That should be possible - although you may find the GPU->CPU bottleneck on some hardware.

Some other things I have done with AI and blender include:

Testing IK solutions.
GUI's to display telemetry and provide control of various chassis,
Prototype control algorithms for hardware (eg four wheel omni-steer chassis - how do you co-ordinate the wheels?)
Robot hardware design - doing in in blender+BGE allows it to be tested inside the game engine before building it.


Blender background simulation (GUI-less) is different from the actual simulation

Found the method that selects all the objects. I added the below line before visual_transform_apply() and it works as expected.

bpy.ops.object.select_all(action='SELECT')


The Proportional editing only affects vertices in the circle of influence (Scroll wheel to resize)

The default cube is subdivided and I selected a single vertex. Then with the Proportional editing set to random Grabbed and translated on the X axis. Note which vertices are affected.

Then I selected more vertices and repeated the process. Note which vertices are affected now.

I also tried it on a Mesh Circle and the same results occured. I did have to make the circle of influence very very big to affect all the unselected vertices in the circle.

In the video you cannot see the circle of influence, I am guessing it is so big it is off the edge of his viewport.


Twisted bones in unity but not in blender

Try applying your transforms before you export. Select the object then at the top of the viewport click Object button->Apply->All Transforms. Then export it. This solves a lot of Blender to Unity issues and is something you should normally do with exports.
If not that it also might be an armature pose issue between editing modes (Object mode of armature, edit mode, pose mode etc not set properly)


How to handle image creation, search and deletion properly?

This:     bpy.data.images.new(name, width, height, alpha=False, float_buffer=False, stereo3d=False) returns the image created.

bpy.data.images.remove(image) removes the image.


How do I calculate how far an object has travelled in a specific time?

Object distance between frames and total movement length can be done. Set frame_start and frame_end variables.
It calculates selected object distance.

import bpy

o = bpy.context.object
total = 0
frame_start = 0
frame_end = 10
bpy.context.scene.frame_set(frame_start)

for frame in range(frame_start+1,frame_end+1):

    loc1 = o.matrix_world.to_translation()
    bpy.context.scene.frame_set(frame)
    loc2 = o.matrix_world.to_translation()
    dist = (loc1-loc2).length
    print ("Frames:", frame-1,"-", frame,"distance:", dist)
    total += dist

print ("Total distance:", total)


Quick smoke not animating the fire and the smoke

I'm also wondering how can I make the smoke appear on a specific frame.

You can limit the simulation to a range of frames by setting the start and  end  frames under smoke cahe.
you need to save your project to use the smoke cache.


Python UI show value in panel after generation random property

Solution, that generate random values, save it and allow to edit 2 neccesary values from 3 created.
So, value editing not execute in real time, changes is required apply from button (is good for my script with highpoly mesh objects)
import bpy
from random import randint

class VIEW3D_PT_monkeygen(bpy.types.Panel):
    bl_space_type = 'VIEW_3D'
    bl_region_type = 'UI'
    bl_category = "Panel"
    bl_label = "UI"

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

        # Generating button
        # nonstop random values generating in draw function
        # values sending to execute function
        ops = layout.operator('mesh.monkeygen', text='Generate random monkey')
        # all existing values
        ops.op_x = randint(1,10)
        ops.op_y = randint(1,10)
        ops.op_size = randint(1,5) # private value for example

        # Buttons x y, for control defined values in PropertyGroup
        layout.prop(scene.monkeyprops,'op2_x')
        layout.prop(scene.monkeyprops, "op2_y")

        # Apply defined values from PropertyGroup and sending to execute function
        ops2 = layout.operator('mesh.monkeygen', text='From values')
        # only changeable values
        ops2.op_x = scene.monkeyprops.op2_x
        ops2.op_y = scene.monkeyprops.op2_y

class MESH_OT_monkeygen(bpy.types.Operator):
    bl_idname = "mesh.monkeygen"
    bl_label = "Monkey Generator"
    #bl_options = {'REGISTER', 'UNDO'}

    op_x = bpy.props.IntProperty(
        name="Pos x", default=1, min=1, max=10,
    )
    op_y = bpy.props.IntProperty(
        name="Pos y", default=1, min=1, max=10,
    )
    op_size = bpy.props.IntProperty(
        name="Pos y", default=1, min=1, max=4,
    )

    def execute(self, context):
        meshes = bpy.data.meshes
        # remove previos mesh
        for mesh in meshes:
            if 'Suzanne' in mesh.name:
                meshes.remove(meshes[mesh.name])

        #do something
        bpy.ops.mesh.primitive_monkey_add(size=self.op_size, location=(self.op_x, self.op_y, 0))

        # set random values to defined values
        bpy.data.scenes['Scene'].monkeyprops.op2_x = self.op_x
        bpy.data.scenes['Scene'].monkeyprops.op2_y = self.op_y

        return {'FINISHED'}

class MonkeyProperty(bpy.types.PropertyGroup):

    op2_x = bpy.props.IntProperty(
        name="Pos x", default=1, min=1, max=10,
    )
    op2_y = bpy.props.IntProperty(
        name="Pos y", default=1, min=1, max=10,
    )

blender_classes = [
    MESH_OT_monkeygen,
    VIEW3D_PT_monkeygen,
    MonkeyProperty,
]

def register():
    for bpy_class in blender_classes:
        bpy.utils.register_class(bpy_class)
    bpy.types.Scene.monkeyprops = bpy.props.PointerProperty(type=MonkeyProperty)

def unregister():
    for bpy_class in blender_classes:
        bpy.utils.unregister_class(bpy_class)
    del bpy.types.Scene.monkeyprops

if __name__ == "__main__":
    register()


Is there a way I can specify my loopcuts' distance from the edge using units instead of a [-1,1] value?

In this case, CtrlB beveling would give you a quick, clean result, with the settings as shown:

Or put the same settings in a Bevel modifier, for instance, by Bevel Weights, for a less destructive method.


Use of voxel data in Smoke/Fire Simulations

I will go ahead and post this although I am not sure that it will completely satisfy all points of your question. I found this to be an interesting question that allowed me to learn some new things as I researched it, so thank you for that.

I found the currently supported attributes for smoke and fire to be located at lines 1114-1120 of blender_session.cpp as a result of finding the commit from earlier this year where official support for velocity was added. Heat was added at roughly the same time, in this commit. You can see also in the 2.78 Cycles release notes here that official support was added for heat and velocity.
 I was not aware that they could also be seen in /addons/cycles/kernel/kernel_types.

The description for the heat attribute (from the commit where it was added) in cycles reads as follows:

  Similar to velocity, it was kind of supported by the mesh manager but
  was missing a code in BlenderSession to get actual values.

  In Cycles Heat is an attribute which goes from -1 to 1, where -1 is
  the coldest ever temperature, 1 is the hottest ever one.

Now to your main points(I'll do my best):

  are all voxel data always available in the smoke domain or is that
  determined by the flow type of the flow object ?

It appears that the data is there, but perhaps only to a certain degree, if you will. Smoke in cycles cannot become fire simply by accessing the appropriate attributes. That part would of course be determined by the flow type. To represent this, I did a test. In the following image, there are three domains that each share an identical material. The flow object in each domain is a plane, with flow type set as the text before it states. Note that here, I added the velocity attribute to flame to get the result I did with smoke. It is not clear to me exactly how velocity intended to be used, so forgive any inaccuracies in the material. I will edit and correct if I discover an error in the setup.

This is the node setup for the domain:

Click to enlarge

  could you explain a bit more how these voxel data / simulation fields
  can be used in the set up of the smoke domain material

According to the manual, flame is the density of any fire in the domain.   Of course, we can see that flame is the emission, and where we get the light for our fire.

density is the density of the smoke. This is a scalar value.

color is the color given to the smoke in the domain. Color and vector outputs give the same result, while factor gives an average of the channels.

The last two, heat and velocity are fairly undocumented as far as I have found. The only example of usage for heat I found was in a report on the tracker of all places. I have replicated that example here in the node setups posted. The only "official" explanation of them that I have found is what is in the commit where velocity was added for 2.78, as noted above.

  the Smoke Domain Materials I have seen so far only use density, flame
  and color for building the material. What could be the use of these
  other fields ? Could you maybe give an example ?

Certainly. Here is one using both the heat and velocity attributes:

Click to enlarge

The below (low sample) image is the result of the preceding node setup. Instead of using color for the smoke here, I instead used  velocity, and it turns out nicely. Heat is used to drive emission along with flame.

I have enjoyed learning as I have researched this,and I hope that this is helpful, and that perhaps I have answered at least some points of your question well enough.

Edit:

Here is the .blend file containing the domain materials shown above.


How to avoid doing physics simulation and get the final rendering quickly?

No, it needs to calculate each step through the animation to make sure that the physics are correct.  There is no way to "cut in line."

Think about it in terms of a stream of marbles across a plane in Blender.  If (theoretically) you could calculate the end frame, you would image a line of marbles moving along.  But due to calculating the end frame, you missed the fact that a cube slid across the path, pushing marbles out of the way.

Blender needs to calculate every frame to make sure physics are correct.

If you already know the locations of the objects you want on the end frame, then I recommend just placing the objects there.


Adding a pole target causes bones to ignore their IK constraints

As it turns out, this is impossible. The issue of ik constraints being ignored because of a pole target is a known problem. Hopefully support for this function will be added in the future. I might have to look into fixing it myself.


Warning from custom panel unable to get Python class for RNA struct ''

I've coded a fair amount of scripts that use Blender's layout api, but i've never ventured into subpanels. So i may be misunderstanding the intent here.

try

class General_sett_subpanel(bpy.types.Panel):
    bl_idname = "SUB_PT_Gensett"
    bl_label = "General Settings"
    bl_space_type = "VIEW_3D"
    bl_region_type = "UI"
    bl_parent_id = "MAIN_PT_Mainpanel"

notice this drops the inheritance of the Mainpanel, but forces you to add bl_space_type and bl_region_type explicitly.  I'm not sure it made sense to inherit Mainpanel, the Mainpanel's poll function will determin if the subpanel is displayed anyway.

either way, this does suppress the warning.


Is it possible to append objects to the same layer as they are in the source file?

When you click append, select all your objects then in the lower left hand corner, there should be an option panel. Untick the Active Layer option.


How to remove unused textures and materials

If you go to the outliner and set the mode to "blend file" you can control the contents of the blend file. (And remove textures, materials etc if they are not in use at the moment)

For the issue of multiplication when importing I would really go through the import settings and make sure that you aren't importing materials/textures, and then just recreate the shading in blender after import.


yellow rectangle around the camera in 2.8 Beta

It is part of the new gizmo system.

Certain object types have a new gizmo that allows controlling specific object properties directly from the 3D view.

For cameras you can control the focal length.

For spot lamps you can control direction and angle.

Other object types have different controls.


Precise Box creation (migrating from 3d MAX)

A long winded answer.

Most primitive objects (the ones created by pressing ShiftA) will display a creation menu on the toolbar (T) that will allow you to precisely control dimensions and some variables for that particular object. The same menu is available by pressing F6

Example:

Note that this original creation menu is only available when you first create the object. Any transformation (move, size, etc) will freeze the object with those settings and pressing undo will not bring back the original menu. Any further transformation will have to be done by editing the mesh.

Now, down to the issue with your box.

Blender does not have options to create Cuboids with precise dimensions, so you're stuck with creating a cube.

In the case of the cube there is just an option for radius, as is presumed that in a cube all edges will be the same length.

To create a cuboid you need to deform a cube in Object Mode to the desired dimensions, using the transform section.

Once you set the size it is very important to Apply the Transformation (press CtrlA).

Please read:

Why is it important to apply transformation to an objects data?

and

Why do the measurements of this object seem erroneous?


Script to remove submesh in all objects by material name?

The script will loop through the selected objects and through their  verts/edges/faces to remove the ones assigned to a specific material and delete them :

select all the objects
select the material (in material slots )
run the script

import bpy
import bmesh

mat_name = bpy.context.object.active_material.name

for obj in bpy.context.selected_objects :
    bpy.context.scene.objects.active = obj
    bpy.ops.object.mode_set(mode='EDIT')
    obj = bpy.context.edit_object
    me = obj.data
    bm = bmesh.from_edit_mesh(me)

    mat_id = bpy.context.object.material_slots.find(mat_name)

    for v in bm.verts:
        delete = True
        for f in v.link_faces :
            if f.material_index != mat_id :
                delete = False
        if delete :
            bm.verts.remove(v)

    for e in bm.edges:
        delete = True
        for f in e.link_faces :
            if f.material_index != mat_id :
                delete = False
        if delete :
            bm.edges.remove(e)

    for f in bm.faces:
        if f.material_index == mat_id :
            bm.faces.remove(f)

    bmesh.update_edit_mesh(me, True)
    bpy.ops.object.mode_set(mode='OBJECT')


Make sure you have NOT turned off render of the particle emitter or particle system

Turn Physics to None. Stop all animation of Bee.

Stop your particle rotation.
Perhaps your particles are rotating inside the sphere.
Increase the particles.
Move the frame cursor.
Save your file.
Close the file and open again.
Blender particles can become out of synchronization.

Set keyframes for you particle settings if necessary.
Bake to cache.
Then render.


Why is the blender exchange option missing from the export tab in makehuman?

The .mhx export code  wasn't included in MakeHuman because it's quite heavy. You have to download and install it separately. Follow the instructions and you should be fine.

https://bitbucket.org/Diffeomorphic/mhx2-makehuman-exchange


Glass material: object shown with strange artifacts

It looks to me like there are still faces left inside your mesh.
Like this:

What you need to do is delete those inside faces.  This can be done by just selecting the center vertex of each circle and hitting X on the keyboard and then selecting delete vertices.  Your final clean mesh should look like this:

Hope this helps!


Does image texture resolution impact rendering time?

Render time will likely be affected, but not much so, in theory it should make a negligible difference unless you are working close to your hardware limits.

It will however have a significant impact in memory consumption. If you have little memory resources available for rendering this may have a more noticeable negative impact, like for example while GPU rendering on a card with low VRAM amount.

Texture size will significantly affect painting performance


If you selected the knife tool in the sidebar on the left, you can just select a new tool (Select Box, the top one, is the default):

Here, the knife tool is selected, so any time you click, it will use the knife. Just select the first box, and it will go back to the default.

Personally, I just use the knife tool by pressing k, and then after i press space to end the cutting, it will automatically go back to normal mode.


SHIFT + ` or SHIFT + ~ No longer works to controll camera with WASD?

Under Preferences -> Keymap search for Fly Mode and click in the Field where it Says Shift' and rebind it to whatever you like to press.
call me oldscool... but for me Shift F for Flymode .. like it used to be works great


"Denoising" checkbox missing in Blender 2.9

Denoising has been moved into the "Render Properties" tab under "sampling"


Rendered image/video loses material and lighting

Managed to find the issue.

Under the render layers tab, there is a material override option, that replaces all materials with only one. My issue was fixed when clearing this material option.

EDIT:

Newer versions of blender don't use layers, but "collections" so the override function is in the scene>View Layer section.

Additional info:

Where is the Layers panel in Blender 2.8?

2.8 - Is it possible to assign (override) a material to a whole collection?


Mass dissolving of quads into a single point

You can try to use the Decimate modifier, but to get clean topology, I am afraid you will have to do it manually, consider a complete retopology of your sculpture. If you decide to fix your mesh, you can speed up the merging process that batFINGER posted in the comments, by using Shift+R you can repeat the last action, thus reducing one step of the merging process. Which normally you will have to press Alt+M and then "Merge at Center", with this you only do it once, and next time it's just Shift+R.

The decimate modifier could get you some results quick, but you will have to keep an eye out for your topology, if you decide to use this method. Keep in mind that it may decimate already good topology you had. Also experiment with the three modes decimate has, "Collapse", "Un-Subdivide" and "Planar".


How to convert Mesh thickness into Colour node?

Haha. Found it! Apparantly Ambient Occlusion from inside measures the thickness colour of the mesh!


How to create convincing rain with a particle system

I assume you know how basic particle systems work.
If not i recommend watching a tutorial on basic particle systems (like this one).

Just spawn the particles like you would do normally.

Then add collision to your surface (the creature in the gif from your op) and set the Particle Dampening.

As you can see on the image, some particles are bouncing off, some sliding down the surface.
Hope it helps.


Some partial animations cannot play as additive in Unity

I had no luck getting the additive animations to work. Still have no clue why my head animation won't play as additive, only as override.

I ended up making an Avatar Mask and masked the character's body parts with it.

This way, my "additive" animations can play as Override. Not the perfect solution -- but a working solution.


It looks like you have Stereo enabled and set to Anaglyph. This mode is intended for use with red/cyan 3D glasses, which enables the viewer to perceive depth in the game. See the relevant wikipedia article.

If you don't want this enabled, set it to None in Properties > Render Settings > Stereo:


What is bone space, armature space, object space, world space, local space?

The description of spaces in the constraints section of the blender manual is fairly good: https://docs.blender.org/manual/en/latest/animation/constraints/interface/common.html#space-types
If you are familiar with the concept of local space vs world space, then object/armature/bone spaces are particular local spaces. Object space is the local space for a given object (e.g. mesh, curve, empty etc). Armature space is the object space of an armature, but is especially relevant in pose mode when contrasting with bone space, which is of course the local space for an individual bone.


How do I get constraints to work in game engine?

Ok. got i figured out.
i just needed to use the "edit object" actuator and change it to track.

I was trying to create a gun that aimed at a moving object, which, in my case was cross-hairs that moved with my mouse. The problem I encountered was that when I added a 'Track To' object constraint to my gun, it would work in object or edit mode. However, when the game went into run-time, the object would stay immobile rather than tracking to my cursor as it had before.

The solution was removing the object constraint under the properties panel, and adding an 'Edit Object' actuator to the gun, changing the type to 'Track To'and selecting the cross-hairs as the target object.

Afterword, enabling '3D' tracking allowed my weapon to follow the cursor even above the 2-dimensional plane it was on.


What is a good approach to modeling objects with too many details?

These objects are pretty detailed and might require some time to create, but you definitely don't need any paid add-ons.

So here's how I would recreate the lower model:

Start with a cylinder.
Taper the rear end.
Extensively use boolean to cut out undesired portions. The basic shape of this model should be almost completely re-creatable with Boolean modifiers. Don't worry about things like smoothness just yet, you're still roughing out the piece.
Make a safety-copy of your mesh and Apply all the previously created boolean modifiers. In edit-mode select the sharp edges that should be smoother and hit Bevel Edges (with the mouse wheel the "roundness" of these new bevel can be increased).
Add and apply a Multiresolution modifier (set to simple not Catmull-Clarck) and add final details to the mesh.
(If the polygon count is too high) Create another copy of the mesh, reduce it's polygon count with the Remesh modifier and bake the details of the high-poly mesh to the low-poly mesh using normal-maps.

If this is hard to understand by just reading through, I'd recommend this extensive playlist.


How do I turn on path influence while keeping the object's position?

See Blend file below  (Vers 2.77a)

I've done this using an empty to follow the path and the cube simply being parented to the empty at the path's starting frame by using a "Child-of" constraint.  The constraint takes over at the intercept frame and releases the cube again once the path trek is complete.  The path is moved away, leaving the cube behind.

There's a bit of fiddly stuff with the Child-of constraint and that's been outlined below.  My thanks to whoever put this together months back, explaining exactly how to remove the 'Child-of' cleanly and without the model jumping back to it's starting point.

-=================-

The Itty Gritty -

Set up the path first, using an empty to follow the path.  Get that working right.   In the Dope sheet, slide it's valuation keyframes forward to the frame where the cube is to enter or intercept the path.  The path's empty will then delay it's start until that frame.

Animate the path to intercept the cube a frame or more before the path empty is due to move.

The cube must now be parented to the path's empty using a "Child-of" constraint.

Take the timeline cursor to frame 1 and set the constraint's influence slider to zero.  Keyframe that.

Take the timeline cursor to the frame before the path empty is to move and keyframe the constraint's influence slider again. (still at zero)

At the next frame give the influence slider a value of 1 (100%) and keyframe that.

The cube may want to jump when this is entered.  Simply click the 'Set Inverse' button in the constraint.  The cube should return to where it was and will then be parented to the empty.

The empty will follow the path and take the cube with it

-===========-

At the frame where the path-following stops, keyframe the constraint's influence again. (value of 1) and also keyframe the cube's Location & Rotation.

Move 1 frame forward

Select the cube and open the Object menu below.  choose "Apply -> Visual Transform", do not move the timeline cursor!

Keyframe the Child Of Constraint's influence to 0%

Keyframe the cube again. (Location & Rotation)

You can now move the timeline.  The cube should again be free of constraint.  i.e. no longer parented to the path's empty.

The path can now be animated away, leaving the cube behind.


screen is black when rendering in cycles

Only apply if you cannot see by pressing F12

Make sure you don't keep any hidden object in front of camera.

Check your right hand column if there is hidden object or not.

You can hide by clicking on eye stuff click again for un-hide.


How to animate UV mask position in Blender Render?

Summarizing, You have minimum three ways to transform UM map:

"Mapping" node in the node editor.
"Mapping" texture.
Use UVProject or UVWarp modifiers.


Use filemanager to select directory instead of file?

I presume the main question here is selecting a root directory with the FileSelector.
bpy_extras.io_utils.ExportHelper includes FileSelectParams, which when set give the desired functionality.
The first attribute to be set is:
use_filter_folder = True
This will filter anything that is not a folder to the user. This also has the added advantage that the path your script gets back is folder.
You also need to set a file extension type, even though it is not used. It will cause an error on execution. Possible bug?
filename_ext = "."
This is based on an for general file import - How do I get the filepath when I import a file?
Full sample
import bpy
from bpy_extras.io_utils import ExportHelper

import os.path

class ExportOperator(bpy.types.Operator, ExportHelper):
    """Operator for setting a directory path."""

    #: Name of function for calling the nif export operator.
    bl_idname = "export_scene.folder"

    #: How the nif import operator is labelled in the user interface.
    bl_label = "Export to folder"

    filename_ext = "."
    use_filter_folder = True

    def execute(self, context):
        userpath = self.properties.filepath
        if(!os.path.isdir(userpath)):
            msg = "Please select a directory not a file\n" + userpath
            self.report({'WARNING'}, msg)

        #Insert the desired logic here to write to the directory.

        return{'FINISHED'}

def menu_func_import(self, context):
    self.layout.operator(
        ExportOperator.bl_idname, text="Export Scene to folder")

def register():
    bpy.utils.register_module(__name__)
    bpy.types.INFO_MT_file_import.append(menu_func_import)

def unregister():
    bpy.utils.unregister_module(__name__)
    bpy.types.INFO_MT_file_import.remove(menu_func_import)

if __name__ == "__main__":
    register()


How to make a plane that has been deformed straight?

Try scaling with a value of 0 on an axis, that will straighten it for you.

Maybe try all three axis and see which one will fix it  (S, X, 0, Enter ), also try the Z and Y as well .


why does the texture gets stretched on my rectangle shaped object?

The stretching is happening because your model's polygons are rectangular, but the UVs are square. Apply Scale to the object before UV unwrapping.

To apply scale, select your object in Object mode, then go to Object > Apply > Scale (or CTRL + A > Scale)


In this tutorial you will see exactly what is needed to learn do to to get something similar as described.

https://youtu.be/k8lHVnQdtSA


Animation Nodes: Simple Grid Mesh not working

You need to extract the number of instances from the vertex list:

There is only 1 grid mesh, so it feeds just single instance.


UV texture not rendered as seen by camera?

The problem is that you have 2 UV maps defined for the mesh, and the one selected ("UVMap") is applying the image texture the wrong way.

If you select the other map ("UVMap.001"), you'll get the mapping that you want.


High to Low poly normal map appears to have seams all over and looks warped

You probably want to switch your lowpoly model to smooth shading, before baking the normal map. I also can't tell how big your texture is, but the UV map has an awful lot of wasted space.


Help With Adding Bones To An Already Deformed Armature

Go into 'Edit Mode', Shift+a to add an armature bone. Parent the new bone to the existing armature. Place the bone within the mesh at the proper location. Even if the mesh model is already parented to the armature, parent the mesh again to the full new armature.

In 'Edit Mode' the PoseBone deformations will not show. In 'Pose Mode' you can deform the armature and the mesh model will follow.

If the automatic weight painting is not satisfying, you can manually edit the weight painting for each bone in the armature. You do this by clicking on the mesh, and then selecting 'Weight Paint'. Then select the armature that you want to fix the weight distribution.

Good Luck!


Break node connections from within Property Editor?

Sure. Click the linked shader property and select Disconnect from the list in order to break the connection. You can also select Remove if you'd like to get rid of the linked node:


Can game settings be changed dynamically?

The bpy module is unlikely to have any effect during game play; you should use bge instead. Try bge.render.setEyeSeparation().


How do I zoom in on a planet from space to ground level?

I would make it into few scenes that I would then merge in post-production.

Scene 1 - from space, getting close to planet, you could have sunflare, satellite or whatever cover view for a moment, so you could load Scene 2 then.

Scene 2 - Scene 2 starts exactly where Scene 1 ended, with more detailed planet done. It would be going from planet to some upper atmosphere clouds, at point in time cloud would cover view, that is the moment when you start scene 3

Scene 3 - starts exactly where Scene 2 ended, with same cloud covering the scene, but with much more detailed ground and you getting even closer.

And basically that would be it - each time you'd want to increase your details you would have to find a way to cover view for a fraction of a second to switch scenes seamlessly. This way you could do it all the way to the ground and beyond :)


Try using data transfer modifier. Vertex Color is in Face Corner Data. If Your objects have same topology, the best setting of matching vertex is Topology, otherwise try nearest corner and best matching normal:


When "is_library_indirect" property of ID's could be set to True?

I have figured that out. It is set to true for objects that located in linked groups.


I think you pressed CTRL + SPACE. The shortcut maximizes the view of the window you are hovering over.

Note : If you emulate a 3-button mouse, the shortcut is ALT +  CTRL + SPACE.

Press this combination again to go back to normal.


Achieving a feathered transparent effect

You can do this with a Fresnel node or a Layer Weight node.  Both these nodes give higher values (close to 1.0) at grazing angles and lower values 0.0 straight on, and thus can be used to mix in pure transparency towards the edge of your sphere.

The difference between the two is the interpolation curve.  The Fresnel node uses the Fresnel function, which is technically meant for defining amounts of glossy reflection but still often gives pleasing gradients.  The Layer Weight's Facing output uses a linear gradient from straight on to grazing angles.

Cycles

To use this to control the transparency as you want, mix a pure white transparent shader with your colored transparent shader and plug the Fresnel or Layer Weight into the Mix Shader's Fac input.  The above result used the layer weight node, like the following nodes.

Blender Internal

Though Blender Internal has no specific Layer Weight or Fresnel node, you can make one from scratch with a little bit of vector math.  Just use it to control the alpha of the output node.

This uses a Converter > Vector Math node to take the dot product of the View vector and the Normal vector.  Here I have also added an RGB Curves node to adjust the falloff curve manually.


automatic weights won't connect skeleton to mesh

You need to:

Select all you mesh parts
Select your armature while selecting the mesh using Shift+RightClick
Hit Crtl+P then choose With Automatic Weighting

And all will be good as shown below:

As @lemon mentioned, although it will work without joining the mesh parts together, but it's better to join the mesh parts together then apply the parenting to use the dog as one object instead of having many objects representing one object as this will avoid a lot of mess. To join the mesh parts select all mesh parts using Shift+RightClick then hit Ctrl+J


How swap views between multiple cameras?

There are multiple different ways. These are only a few. They can also be mixed together.

(1).1 Bind the camera to a marker

You can do that by binding the camera to a marker on your timeline.

You can create markers on the timeline with the M key. Then select the camera you want to bind to that marker and hit Ctrl+B. As soon as your timeline reaches that marker the camera will switch. It is important that both the marker and the camera are selected.

(I forgot to turn the screencast keys on, see description above)

(1).2 Use multi-view (for stereoscopy)

You can enable multiple views in the Scene tab of the Properties panel. These are basically for stereoscopy-like effects, not for switching cameras, so I will only post a link to the manual: https://docs.blender.org/manual/en/dev/render/workflows/multiview/index.html

(2).1 Use the video sequence editor

The fancier (and maybe better) way is be to render the scene multiple times with the different cameras activated. Save the single frames in a lossless format. Then you can easily import them to the video sequence editor as strips and use the cross blend mode. You can then adjust the opacity value with keyframes (hover and I)

video sequence editor (old gif)

Edit:

In this animation I use the camera override tool of the vse. You simply set up your scene and your cameras (with everything, including animations). Then in the video sequence editor add your scene strip multiple times (Shift+A) and set your camera override in the right panel.

Although I created a new scene (that was supposed to hold the scene strips). I forgot to switch back to that scene after switching to the vse. It is recommended to always use a separate scene for the sequencer! It may work in this example, but maybe not in bigger projects.

(2).2 Use the compositor

You can also add your frames to the compositor and mix them with very fancy effects. Then you can add this whole compositing scene to any video sequence editor. By the way: You can also add layers from other scenes directly to the compositor with the Render Layers node. But then you need to copy your scene and if I got you correct this is not what you want.

It is possible that this is not what you want, so choose your tools wisely.


How to change camera to current view on LAPTOP

In user preferences, if you use "Emulate Numpad", it gives the regular 1-0 numbers the same functionality as the Numpad:

Of course, if you don't want to go to the trouble of remapping your keys, you can always just select it manually from the view menu:


Apparently the problem is with using the file on different computers.
I didn't even think it could be a problem.
When I render it on my laptop the astronaut has his limbs, but when I send it over to my friend computer he doesn't have them in the viewport.


Can't hide object which particles are based on, without losing particles

Select the large torus.

Blender 2.7x

Press the M key and change the layer it lives on.

Then in render layers Shift-Select the layer you chose to remove that layer from being render.

Blender 2.8x

Go to the Object Properties panel.

De-select Show in renders

To explain this, the properties you are changing ar only for the instance you selected, not any instances that are generated by the particle system.


Mesh not following bone after parenting and painting

When you parent an armature to a mesh you need to go into the mesh's object properties and make sure that under Relations->Parent you have the proper Armature object selected and make sure the type is set to armature not Object or Bone.


How to export materials from Blender for use in another 3d software such as Houdini or Unity?

No, none at all as the rendering pipelines are all different for every package. So unless the other package has a similar shader node, allowing you to re-create the shader, you're out of luck and will have to bake out the various textures for application in the other packages. :-(


How do I get this wing to uv unwrap correctly

Maybe join the eyes, in my opinion it's simpler to have only one object.

Your problem is that you have overlapping vertices, it messes up your unwrap, you need to select all in Edit mode and AltM > Merge By Distance.

Make sure that your seams are well placed, i.e. all along the shapes as if it was a costume sewed (see screenshot). Then you can unwrap.

You can increase or decrease the size of some islands (UV map elements) in the UV Editor.

At the end you'll probably need to apply the Mirror modifier for Unity, by default I guess the mirrored left part will overlap the right part in the UV Editor.


The best practice is to take the car you need to model 1 part at the time. If you notice the chasis is broken down into real life individual pieces. The door, the lights, everything is made out of pieces. Also, use references. Then just place objects closer together. No one looks for seams (that are not natural part) of the car's modeling.


You could parent the second duplicate to an empty object and use the offset between the two as the wanted offset between the origins.

As for you other question, I don't think it is in the philosophy of linked duplicates to allow for a different origin.


Volumetric Scatter affected (Same file, different computers) CPU vs GPU

Problem solved by changing sampling integrator to Branched Path Tracing.

This is not needed when rendering on the CPU, but apparently required when rendering on the CPU.

I found the solution here: Volumetric scatter shader does not show light focused through lens correctly


In order to help refine your searches for how to do simulations/animations, here are a few tips and key-words to help you on your way.

For sea-weed, you could start by adding a plane and then also adding a particle system to the plane.
Here I used mostly default settings with the few differences visible in the attached image.

Then I added a Force Field-> Turbulance and animated it's position using two keyframes.

You can also substitute each 'Hair' with a model that is on a separate layer using the following setting.


First, if you install blender with your linux distro,
then a proper installation of python3 and blender with your particular distro should solve your problem.

e.g. for debian:

sudo apt-get install python3 python3-dev
sudo apt-get install blender

Second, if you really want to install the python header files
for the python that runs inside blender, then you can do it the following way:

Find out the exact blender python version:

/path/to/blender-2.78a-linux-glibc211-x86_64/2.78/python/bin/python3.5m -V

Download and install the python header files from the official python homepage:

point your browser at https://www.python.org/downloads/source/
download Gzipped source tarball from the exact same python version as your blender python version
cd ~/Downloads/
tar -xzf Python-3.X.X.tgz
cp Python-3.X.X/Include/* /path/to/blender-2.78a-linux-glibc211-x86_64/2.78/python/include/python3.5m/

That should get you rolling.
Best, Bue


Basically in most cases you need just to Auto Smooth Normals at mesh data properties:

Use Shade Smooth for object globally (or selectively in Edit mode):

Sometimes when you import object from exchange formats may be needed to Clear Custom Split Normals Data:

Another solution to achieve Auto Smooth Normals data effect is applying of Edge Split Modified especially at work with curves or linked data.


Q: Grease pencil, how "Anti-aliasing Threshold" works?

There was a bug with Anti-aliasing  in pre 2.9 versions. Are you up to date?
If you're experience flickering lines when moving the camera or an object then this is a known bug. I believe the fix at the moment is render in double the size and then compress. This works for me but naturally takes significantly longer to render.
Thanks
Matt


How to apply the same texture to multiple faces?

The trick is not so much on how you apply the texture to the faces, but on the texture it self.

What you need is a "seamless" or "tileable texture", and how to make one is not really a question about blender itself, but more a question of image editing or photo editing.

First you must correctly unwrap your mesh, see here how to. You may want to get rid of that NGon on the top too.

Then either search the internet for "Seamless Rock Texture" or  "Tileable rock texture" or create one yourself using some tutorial like these https://www.google.com/search?tbm=vid&q=gimp%20seamless%20texture

Edit

You can't really do heavy texture editing inside Blender, there are some basic tools like painting or material based effects, but for for heavy work you are always advised to use a image editor.

Anyway, upon closer inspection it does seem like your texture is already seamless and tileable, I had not noticed before, so you don't need to do any editing for now. All you have to do is correctly unwrap your mesh as described in the link above.

Still have in mind that your texture is not very big and will still have noticeable patterns when repeated over an extensive surface. That can only be fixed with a better texture.

How will you be rendering the image, Cycles?
You may also reduce or mitigate the repeating effect with some UV distortion using nodes, but don't expect miracles, You could use some of the procedural textures like Musgrave or Noise, or whichever suits you best to distort the UV coordinates and create a disturbance in the texture. Here is an example of how this could be done.

Edit 2

If you want to export this for another game engine don't bother with Cycles for now. Switch to Blender Internal render using the menu on the header of the window.

First step open your image in the image editor
Then unwrap your mesh over it
Add a new material to your mesh in the properties window
In the texture tab of the properties window add a new texture to your material
Choose image texture type and add your image from the dropdown


How do I export an object (that consist of many parts), so its different UVed meshes are preserved?

There is a "Selected Object" Toggle in the FBX-Export Window and also in the OBJ Exporter Window, for only exporting the selected object.

Its possible that the other part of the problem is with the other programm, what other software are you using?


How Can I Subdivide Only Part of a Grease Pencil Stroke (Ver. 2.92.0)?

Select only two points where you want to subdivide, and select Stroke > Subdivide.

Or just right click on the context menu and select subdivide.

Note that you can modify the settings for the tools and the post processing for the draw tools to get better detail and optimize how control points are distributed on the drawn lines.

For more information read the manual https://docs.blender.org/manual/en/latest/grease_pencil/modes/draw/tools/draw.html#tool-grease-pencil-draw-draw


How do I distribute a stand-alone made with BGE (Blender Game Engine)?

Before you export you should do File/External Data/Make All Files Relative and save.

This ensures the paths are relative to the current blend file.

Be aware: This influences the current blend only. When you link to blend files that refer to other files, this file needs to be changed too.

When you export from WinOS you need to deliver all files from your export directory to ensure all the libraries (.dll) are available.


Boolean does not work in Blender 2.8 beta

the problem is that you have overlapping faces on the bottom of your mesh.

in this example i create 2 cubes and try to make a union operation but it doesn't work because the cubes faces overlap when i scale down one cube the union operation works as expected.

good rule of thumb if you work with booleans if you have a problem try to move one mesh until it works.


Change the transformation axis as indicated by the Yellow Arrow below.
Try the different selections to see the effects.

Transformation Axis.

Sometimes a stray keystroke can have an unintended effect.  So many keystrokes.


If you haven't applied the rotation, you can use the local coordinates, either change to locale in the Transform Orientations dropdown, or hit S -> Y -> Y for scaling on the local Y axis (or X twice for X etc.)
If you have applied rotation then creating a new Transform Orientation will be required. Select the face on one end of your cylinder, then in the Transform Orientations dropdown click the + button. This will make a new coordinate system aligned with the selected face. Then scale as required.

But the easiest way for this particular problem would be to use Loop Tools addon. Select the verts on one end, right-click and choose LoopTools -> Circle and like magic your verts with be a circle retaining the plane they are on and their median location!


Is it possible to bake dynamic paint waves simulation as a black and white displacement map texture?

Dynamic Paint can output to different targets depending on the Format. In your example you're baking to Vertex weights. However, changing it to Image Sequence will give you a new Output panel that allows the output to be baked to a sequence of images :

Once stored as a series of images you can use an Image Texture node set to 'Image Sequence' to retrieve the data and use it to drive the Displacement.


Help with putting liquid in glass in blender

In your file the liquid object and the glass object both have the same material. If you give the glass object a separate material without any absorption, it works as expected.

With the glass selected, make a copy of the beer material by clicking the 2 icon:

Remove the absorption node (⌦ Delete):


How to change mutiple parts by changing just one?

There are several ways to do this:
Array modifier
You can use an Array modifier to do this. Use multiple modifiers to make the wall, and then model the design (or model the design first and add the array modifiers later, the order doesn't matter):

Linked Meshes
You can link the mesh data of two objects together by press CtrlL> Object Data. Note that this will make the mesh data of the objects identical, however you can still transform (scale, rotate, etc.) them independently in object mode.
Related shortcuts:

To quickly duplicate and link objects in one step, you can press AltD

To unlink an object or objects, press U> Object and Data.

Example:

Dupli objects
Dupli objects are used to display instances of an object on the vertices or faces of another object. They can also be used to display duplicates of the object in time (dupliframes) or an entire group of objects. Duplifaces are faster and use less memory than the array modifier, see Applying Array Modifier - Still instance?.
You can also use them to make an instanced array modifier (which does not use instances), giving a performance boost. See this question.
Particles
You can do pretty much the same things with particles as with dupliverts and duplifaces, however you have more control over the orientations of the instances.
Plus you can also do some interesting tricks with hair particles or particles with physics.
Modeling
You can do this to some degree with normal modeling tools (useful for some quick symmetrical actions), however for creating something like a tiled wall the other techniques are probably better.
See Mirror changes to side of cube across all six sides


How would I attach text to a tracked point on video clip

Let's say you've successfully tracked an object in your scene:

Go to the Solve Tab and in the Geometry section and click on Link Empty To Track.

That will create an Empty that, if seen from the camera, moves within the frame like the tracked object.

At this point you might want to add your image as background for reference and make it visible for the camera axis.

Add a text object in the 3d View (ShiftA > Text ) and select the Align to View option:

Edit your text, set the orientation to view and place it where you need it.

Select your text object, then select the Empty by holding Shift and simply parent it to the Empty (CtrlP).

The text will now move like the tracked object.

To render both images create a node tree like this:

If the text element is an image and not a 3D object

You can overlay the background video with the foreground element using the compositor:

The text (with a transparent background) is placed and scaled with a transform node.

The result of that is then passed to a translate node that uses the information from the tracker (select the video used and the object, usually "camera" and the tracker you want to use to control the movement)

Then use an Alpha over to overlay the image on top of the video background.

Tracked image in the  Movie Clip editor:

Result:


The following script allows you to enable all GPUs and optionally all CPUs as well.

import bpy

def enable_gpus(device_type, use_cpus=False):
    preferences = bpy.context.preferences
    cycles_preferences = preferences.addons["cycles"].preferences
    cuda_devices, opencl_devices = cycles_preferences.get_devices()

    if device_type == "CUDA":
        devices = cuda_devices
    elif device_type == "OPENCL":
        devices = opencl_devices
    else:
        raise RuntimeError("Unsupported device type")

    activated_gpus = []

    for device in devices:
        if device.type == "CPU":
            device.use = use_cpus
        else:
            device.use = True
            activated_gpus.append(device.name)

    cycles_preferences.compute_device_type = device_type
    bpy.context.scene.cycles.device = "GPU"

    return activated_gpus

enable_gpus("CUDA")

The script can be called from the command line by starting Blender with the -Por --python flag followed by the path and name of the script.


Speed up Cycles Render: Only calculate whats visible to the camera

It's not really limiting the render to what's visible to the camera, but you can limit some effects to camera, such as bump maps.

Mixing your bump BW factor with a 50% grey color with light path's "is camera ray" to make your bump map only visible to the camera. Add (math node, clamp checked) "is camera ray" with "is glossy ray" to have your bump visible in glossy reflections too.


Use a translucent shader and mix it with your current shader.


Your texture has to be an environment texture (node) and mapped as equirectangular or mirrorball (if it looks rounded) in world settings.

check "world background" to see it in viewport (perspective view, not ortho)


Stopping a character fall in Blender Game Engine

The way you implemented a solution is that the object has no gravity.

This is not really the behavior of an object that "holds on another object" (character holding at the ladder).

You currently discover "an area without gravity". That means when the character jumps into that area it will preserve it's motion and direction (while gravity would would do the same but adds another force influencing motion and direction).

I suggest you implement a "holding" onto the ladder, e.g. by parenting the object to the ladder [or any other way to restrict the position to the holding point].

While holding any previously active controls (like jumping, walking crouching) will not work anymore as the character is not a freely moving physics object. This is fine, because your character holds itself to the ladder.

You need other "operations" like move up/down (but not via linear velocity and such things).
Additional you should implement a "release operation" that let the character release the grip returning to the normal behavior (incl. falling).

Other operations could benefit from release too - you can combine jump and release. I suggest to first release and jump afterwards. Otherwise the exiting "hold" would disable the jump.

What problems could happen?

A) Parenting is a hard attachment. This means when you throw the ladder around, the character will not care and still hold onto it. If you really need such situations, you could release the character before (or while) moving the ladder.

B) The character ignores collisions while moving on the ladder. While parented the physics has no influence. Unfortunately there is not much you can do here, except sensing for such collisions and acting accordingly. E.g. you sense if there is a blocking object above the character before allowing the "move up" operation.

I hope this helps a bit.


How to turn my honeycomb pattern into the sphere?

You may achieve it beveling the Ico Sphere (Percent mode) and inseting the faces.

Add an Ico Sphere and subdivide it (in my case I've made 3 subdivisions).

Select the whole mesh in Edit Mode with A and press Ctrl+B to bevel it. Use the Mouse Scroll to reduce segments to 1. Press M twice to enable the Percent mode and scale hexagons to lay as close to each other as possible. Next remove doubles with W-->Remove Doubles. Increase the Merge Distance value if needed.

NOTE: You can achieve similar effect using the Bevel Modifier, but geometry may be more dense then.

Now add a Subsurf Modifier with some subdivisions and smooth the object in the Tool Shelf's (T) Edit panel. With the whole mesh selected press I twice to inset individual faces, then scale the faces inwards to create the holes.

Finally with the whole mesh selected (A) press Shift+E to crease the edges. Play with the Mean Crease value in the Transform panel of Properties Shelf (N) to adjust its strenght as you like.

FINAL NOTE: The model has pentagons as @kheetor warned about, but they're not much noticable.


Why can't I set a rotation keyframe on this object without it setting the same keyframe on the parent armature? Deleting one KF deletes the other too

Turns out this was a case of user error. Bezier 1 was using the same action as the armature, and this is the normal behavior in that situation.
I was (incorrectly) thinking that an action just stores the entire timeline, including keyframes for each individual object that uses that action, because I hadn't had any problems using it that way with armatures. But in actuality, an action just stores the individual properties that are animated, and applies them to every object that performs the action, unless the object doesn't have that property. Which does make more sense in hindsight. I haven't had any problems using a single action for multiple armatures, but that's only because they don't have any bone names in common.


My UV unwrapped image flips between edit mode and preview mode

Okay, I figured it out with a suggestion from Jachym Michal (I think it was you).

The boolean modifiers were messing with the uv map. Which makes sense, when I think about it.

After applying the modifiers, I needed to go back in and redo the UV map to make the image appear where I wanted.


Subdividing and smoothing part of a mesh

@edna's comment is actually the answer, in my opinion. I too have had nightmare creations resulting from using a subsurface or multi-res modifier on the whole model, and creasing, preserving sharp edges etc. It's useful when it's useful, but it adds complexity that you might not need, and it can be hard to fix when overused. Using subdivide on a selection and then adjusting the smoothness and other attributes is better for times when you need higher resolution and smoothness only for certain parts. Example:

Say I want this to look a little more like and axe. If I multi-res or subsurface modify the whole thing, I will lose all the blocky shapes, and I'll spend a lot of time editing to try and preserve sharpness. In a worst case scenario, I'll end up with lots of extra geometry that interferes with 3d printing, rendering, or whatever. Plus it's just a pain in a simple case like this. So enter subdivide:

I turn off "ngons" because if it is on I may create geometrically unsound quads. Make a few cuts, add a bit of smoothness, and now the center of the axe has a puffier shape at the top and bottom. Next, the blade:

Notice the blade is smooth, but the nearby geometry was allowed to stay simple and pointy. (Real technical terms in use here).

I can proceed like this and make any number of more complex protrusions on an otherwise simple or blocky object. Notice that the parts I left alone remain simple, while other parts have different levels of complexity as required:

I hope that helps.


Is it possible to pack a sequence of images into a .blend file?

You can of course pack many image data blocks,
but you can't pack the frames of an image where the Source is set to Image Sequence.


Masks can be combined as images. Use a color mix node and add (or subract) different masks. In this example a couple of garbage mattes have been combined to be used by a single keying node.

Or you can combine the resulting image with others that have an alpha channel already using alpha over.

Or combine the alpha channels separately and associate them later using the set alpha node.


There is no need to make the background white (or green) when you can make it transparent without more processing. The idea is to use the mask information to determine which parts of the image are opaque and which are transparent.

Don't use the mix node.

Use Set Alpha, so that your mask controls the transparency of the video: Whatever is white on the mask will remain opaque, the black areas will be transparent.

If you need to re-position or re-scale the elements do so after the set alpha node, so that the transformation happen as a single combined element.


BGE. Is it possible to create transparent plane with blur filter?

I never used BGE and you blend file link gives a 403, but here's how I'd implement that effect:

Normally in a game engine:

Render your scene to a texture. That's the first step you normally do for post-processing.

Render the glass pane to another texture. The glass pane should be white, the rest black. Disable material and light for faster rendering. If your glass pane is partially hidden by other objects, these parts should also be black in your rendering.

Blur your original rendering. Use the black/white texture as a mask so only the glass pane gets blurred. Alternatively, blur the whole image in a copy and use the texture to combine both.

In Blender:

Here's my node setup with an exaggerated version of the effect. On the right, the blur map. I used the object ID pass to generate it.


Link python array to x-position of element

You can do it with something like that (the code is commented, so I think it is clear):

import bpy
from mathutils import Vector

scene = bpy.context.scene

# Get the object
obj = bpy.context.object

# Define first frame and frame step
frame = 0
frame_step = 10

# Your x positions array
x_positions = [0,0.1, 0.5, 0.7]

# Loop over positions
for x in x_positions:

    # Set the current frame
    scene.frame_set( frame )

    # Assign the location
    obj.location.x = x

    # Insert a key frame (replaces old one for this data path)
    obj.keyframe_insert( data_path = 'location' )

    # Go to next frame
    frame += frame_step


How to animate a closed string as in string theory

I think he has used a Displace modifier:

Create a circle, extrude, deform a bit, give it a Displace modifier and a Subdivision Surface modifier. Choose the Displace Direction:

In the Displace modifier, click on Texture > New, and in the Texture tab, go select the Clouds texture. Play with the Size and Depth.

When you'll move the circle it will deform along the given direction.


Make sure 'Auto Run Python Scripts' is ticked in the File -> User Preferences Menu. I had the same problem and that fixed it.


There's currently no way to emulate film grain without the compositor.

This is obviously a crude workaround, but you could find a film grain image sequence or video, (or somehow make one procedurally using nodes), and use it as an alpha texture for a plane. Then, constrain the plane's rotation and location to always be right in front of the camera. This wouldn't work if you need Depth of Field, but it would probably work ok if you didn't use DoF.


This is the default or norm in Blender to have the texture appear on both sides. There is no setting to change this. This also doesn't need to be changed often as usually only one side of a model is showing.

The way I go around this to have the material appear only on one side is to use material nodes and have the base material on one side and a transparent material on the other.

It is a bit tricky if you don't have any experience with material nodes but just follow the node layout and it should work.

Just unwrap and texture as normal and setup your material and then add a second one, enable Transparency, set the Alpha to 0 and turn off the specularity.

As you can see below, both planes have textures but only one shows up when rendered. That is because I have added a transparent material to it along with the normal material and used the Geometry node to pass the materials to the different sides. One of the planes is on one side and the other is rotated 180 degrees around to the other side.

Here is the node setup for the material. (larger image here)


First make sure you choose GLSL shading mode in the properties panel of the 3D view (shortcut N):

Then, you can switch the viewport shading method to Texture in the bottom menu:

Then, your object will appear transparent (if you set up the material correctly ;) even in edit mode.


Filmic blender uses  a different scale than sRGB, it is designed for a much wider dynamic range, so to get white it is necessary to increase the intensity of the light for that background.
The standard sRGB transform will display "white" when the scene values reach a value of 1

Using the filmic blender transforms, you need a much higher value. "White" is at a value of 16.19.

To visualize how the scene referred values are being mapped using the filmic blender you can use the false colour view transform.
To understand what filmic blender does and how it maps the scene's values to the displayed image please read the following link: Render with a wider dynamic range in cycles to produce photorealistic looking images
and https://github.com/sobotka/filmic-blender


Can I get the object dimensions in Cycles?

Well, I can answer part of the question. You can get the values of the dimensions into cycles by using drivers, driving 3 separate Value nodes and using the data path of dimensions[0] as the driving value:

Add a Value node: Add> Input> Value
Right click the value and choose 'Add Driver'.
Change to the graph editor and change to 'Drivers' mode from the header toolbar.
Use the following settings in the Property panel (N) after selecting the channel on the left:

As you already identified the data path you need is dimensions[0] (0, 1, or 2).

This will result in:

(6.399 simply being the X dimension value of my test cube)

Repeat this for the 2 other dimension values and 2 more value nodes.

However, as to how you would combine 3 value nodes into a vector is something I don't know. You could of course drive something other than a 'Value' node using this method if that is more useful.

Edit: As noted by Chebhou, in the comments, as of Blender 2.72 a "Combine XYZ" node exists:

Instead of driving 3 individual 'Value' nodes, you can now drive the x, y and z values of the 'Combine XYZ' node which will result in a vector.


Copy settings from one particle system to another

If you can do some python.
Traverse all the objects and then traverse all the modifier of this object, if the modifer is a subsurf set the modifier correctly.

for ob in bpy.data.objects:
    for m in ob.modifiers:
        if m.type == "SUBSURF":
            ob.cycles.use_adaptive_subdivision = True
            ob.cycles.dicing_rate = 3
            ....

And do the same for the particule system:

for ob in bpy.data.object:
    for psys in ob.particle_systems:
        psys.use_hair_bspline = True
        psys.render_step = 5
        psys.adaptive_angle = 2
        psys.adaptive_pixel = 3


Once you setup the user interface to your liking, pres CtrlU to save as startup file.

Then enable Load UI in the system preferences, and press Save User Settings, so that every time you open blender, it will use your modified UI.


The SSS material is the one your going to want to use. The reference is showing light scatter. The issue your having is lighting. There's not enough light for that edge to show.

Here's what I got after a few minutes of experimenting:

I have a large light source has a strength of 10.0 and I have an environment map in the background. That's what gives it enough light to scatter.
Here's the scene setup:

Your shader looks OK, but if your interested, here's mine:


Rotate object on local axis using a slider

By using obj.matrix_world *= Matrix(...) you apply the rotation on top of the existing matrix, which explains the behaviour you're seeing.

Rather than changing the matrix, why not go to the source of the rotation itself, the rotation_euler property? You can just do obj.rotation_euler.z = radians(self["rotate"]) and let Blender to do the matrix math for you.

Alternatively you could use a driver that reads that particular window manager property.


Here is the script which :

goes thorough vertices and find the highest
select it and what is linked to it
separate it with separate(selected)

after applying the edge split modifier run this script :

import bpy

obj = bpy.context.object
bpy.ops.object.mode_set(mode = 'EDIT')
bpy.ops.mesh.select_all(action ='DESELECT')
max = -9999
for i in obj.data.vertices :
    if i.co[2] > max :
        max_ind = i.index
        max  = i.co[2]
bpy.ops.object.mode_set(mode = 'OBJECT')
obj.data.vertices[max_ind].select = True
bpy.ops.object.mode_set(mode = 'EDIT')
bpy.ops.mesh.select_linked()
bpy.ops.mesh.separate(type='SELECTED')
bpy.ops.object.mode_set(mode = 'OBJECT')

#bpy.context.selected_objects[0].location[2] +=1


How do I UV unwrap and texture onion-like object?

You want to UV unwrap it such that you get a square/rectangular UV island. Then you can use an image texture that is setup for polar coordinates. The trick with a sphere is that you have to remove the single vertex at each pole to unrwap it properly.

Create sphere.
Delete vertices at each pole.
Set viewport to ortho mode and view the sphere directly (front or side, no angle).
Unwrap via sphere projection. Your UV island should be square.
Create a polar coordinate image texture (features run from top to bottom).
Apply to texture using UV coordinates. I've used a Texture Mapping node to increase the X scale so that it tiles more horizontally.


How to only show the paths of Greace Pencil strokes?

As far as the hiding of the strokes goes, I have found a solution:

For whatever reason, the wireframe view was selected.
This problem was solved by selecting any other view in the top right corner (e.g. Solid view).


One of the standards for faking volumetrics is using billboard particles. Back in Blender v2.49, I used to use them all the time. I know that Weta digital used billboard particles for smoke in the LoTR movies. I started a thread on blenderartists.org about it. I did a series of video tutorials about it that are listed in the thread. They aren't the greatest video tutorials, but you may find them useful.

Basically, each particle in your system is rendered as a flat, transparent, circular texture. With enough particles, it will look like smoke/cloud. You can even use textured spheres as your particles if a strictly 3D effect is necessary. I talk about using spheres in the third video.

Alternatively, you can render all your volumetrics in a separate layer using BlenderRender. Then, you can composite them into your cycles scene later.

Here is a video with examples


If you're simply trying to resolve the unwrap distortion, I'd verify that you have no doubles causing un-seamed edges that might be causing the warping.   This can be resolved without touching the object itself, which is what the polycount answer was pertaining to.

check seams
U -unwrap mesh
bring up the UV editor in a separate panel

You should then be able to manipulate the UV as you like.


Is their a way to create half of a model and duplicate other side

Yes there definitely is.

You can use the mirror modifier,  this will mirror your model across its origin (or any other object's origin) and merge the vertices along the seam if you want as well.

To do this first add the mirror modifier to the object in the modifiers panel.

The entire mesh will be mirrored across the object's origin along the selected axis.

You can tell it to merge the vertices along the seam by checking merge and adjusting the merge limit to set how close together vertices must be to be merged.

If you don't want to mirror across the origin you can use any other object's origin as the mirror point.  I usually use an empty, an empty is just a non-renderable object that is used in situations like this.

To do this first add an empty under Shift+A > empty > plain axes.

Then select the empty in the mirror object dropdown of the mirror modifier.


how to symetrize a part of the mesh in its normal orientation/position in edit mode?

In general:

Establish your Pivot (transform origin, somewhere in the mirror plane). This probably involves ShiftS snapping the 3D Cursor to a known point, or the median of some selection, and setting the 'Pivot' to 'Cursor'.
Establish your Transform Orientation, either using the View, or more likely a Custom Orientation (the '+' at the right of the Transform Orientation dropdown). For example, it could be the normal of a face: select the face, and create an orientation from it. Z in that orientation will now be the direction of the face's normal.
ShiftD duplicate your part..
SZ-1 scale the duplicate by -1 in the appropriate axis of your custom orientation, about your pivot.

You may have to ShiftN, turn the mirrored duplicate right-side-out.


Start with a Bezier Circle (Add/Curve) Tab into Edit mode and from the Specials menu w Subdivide the circle twice. Deselect all the control points a then select every other one by holding down shift.

Move the selected control points up (g and then z to constrain to Z axis) then from the Top view NUMPAD 7 r to rotate.

Tab out of Edit mode and add another Bezier Circle and name it "Bevel Profile".

Go into the Curve properties of the original Bezier Circle and increase the Extrude value and set the Bevel Object to be "Bevel Profile".

This shows what we are trying to do and you can edit the "Bevel Profile". Subdivide and this time s scale the alternate control points to make a star shape.

And finally you can add some materials, duplicate, scale etc.


Move particles first and stick to texture target

The Texture force field isn’t how it sounds - it’s actually a means of having fine control over the vectors within the force field by using the RGB colors a bit like a normal map with 0.5,0.5.0.5 being no force and +/- that being strength in each of the XYZ directions - rather than being a force that acts towards a texture.

Probably the best solution would be to create your logo out of geometry (rather than an image - or hidden geometry that sits behind the actual image) and give this a force over its entire surface to attract to the logo, keyframing the force strength to activate it at a specific frame.

This can achieve something like the following :

The 'Text' logo includes a Force forcefield (set to Surface) - initially keyframed to zero strength.

Once the particles have fallen and collected on the floor the gravity field weight is keyframed down to zero (to allow the particles to float) and the Force on the logo is increased to a large negative value to draw the particles. A Drag forcefield slows down the particles to prevent them getting out of hand.

As the particles get closer to the logo the Force can be further reduced to allow the particles to settle down.

Blend file included


Check to see if you have double verts. If not, check if you have a duplicate Object in the same place where the artifacts occur. I can't think of anything else.


Why can't I use the bevel equally on all my loopcuts? Double edge problems

I'm not sure to understand what's the method you're using, what are the problems you're encounting, etc, but if I had to do this kind of walls, I would make only one segment that I would repeat with the Array modifier to make things easier, and for the bricks, if you want to keep the whole thing as one unique object, you could:

Cut some orthogonal lines, bevel them:

Extrude them and bevel the extrusion (for example with a Bevel modifier with Limit Method > Angle):

If you think that there's a problem with this kind of method, please tell me?


What are edge loops and front edges and how to select them?

The selected edges in the picture I attached are edge loops. To select all the way around the loop, hold alt and click. For the bevel tool, just hit control b or apply a bevel modifier in the modifiers panel on the right.


It doesn't work because your "transparent" Principal BSDF is not transparent because the Alpha slot value is 1.0. It should be 0.0. But you don't need to mix 2 Principled BSDF shaders for transparency.
You just need one Principled BSDF. Then plug the mask (Image Texture node) into the Alpha slot of the Principled BSDF node. That's all :-)
Of course, you can do it as you did. But you better would take a Transparent BSDF (instead of another Principled BSDF) and mix it with a Principled BSDF. The mask goes into the Fac slot of the Mix Shader as you did. Such setups are often used for glass and plastic shaders.
Transparent shader nodes don't need a normal map. (At least I've never this.)


In Cycles, when I convert from one output type to a different input type, what is REALLY happening?

1) It is to "initialize" the normal being used to the actual mesh normal. It's a little more proper to do this with the "normal" output of the geometry node instead of a bump node, but the result is the same. The bump node takes an input normal, and modifies it based on differences in the height input. Since the height and normal inputs are both disconnected, it just passes the default normal (which is the mesh normal). Since the vector is being modified via the mixRGB node, it doesn't know to initialize the normal with the mesh normal, and instead uses a constant vector.

2) As noted in the comments, see What is the meaning of the color of the node sockets in the node editor?

Re: Diffuse roughness: theoretically yes. Although in some testing I did once, I recall it giving weird results with high roughness, might be a limitation of the model used by the diffuse BSDF node. Which brings me to...

If you are using Blender 2.79 or later, you should be using the Principled BSDF node, not the setup described in that tutorial. That node setup is essentially an imperfect emulation of the Principled BSDF shader anyway. The mixing of normals is actually a hack to try and approximate roughness-dependent fresnel, which the Principled BSDF supports correctly. The Principled BSDF also correctly matches diffuse and glossy roughness, without you having to do anything.


Why aren't bpy.props defined on the WindowManager saved on permanently?

The window-manager is an exception when it comes to data-blocks, having some characteristics that make it work differently then meshes, scenes... etc.

Can't be added or removed.
Its a singleton (there is only ever one).
Its not saved in the blend file (this is why properties aren't set on reload).

This can be handy, for example - this is used for the add-on and key-map search text fields.

For persistent data, its normally best to use...

the current scene (context.scene).
add-on-preferences
in a sub-directory of user resources (as json/xml/pickled data... etc).


The wiki
says:

  The color of all visible planes and edges attached to the vertex are
  then modified with a gradient to the color of the other connected
  vertices. (Note that the color of non-visible faces are not modified).

As I understand this, it works on gradients which are not available without edges and faces. Thus you can't paint isolated vertices.


Hi @TobiasPenner and welcome. When I opened your Blend file I noticed that the two plains have a white emission material and the cube has the default light-gray. So when you say you viewed as colour I am not sure what you mean. You may have changed a few things before submitting the file, but maybe if you showed an image of the different modes it will help.

Anyhow with your blend file if you want to add color to the cube and see in Material preview mode you will need to do the following:

Change your cube to view as a solid object (it is displayed as a wireframe).

Assign a color in the material properties of the object


You can add shortcuts by right-clicking a menu item or button and choose "Assign shortcut"


Set the snap options 'Face', and 'Project individual elements':

Select the top face(s) of wall, and have a view open looking down the desired axis of projection. (The right-side one, here)

With the mouse in the projection view, Hit G


Project mesh on surface (or clip face with rotation)

To place cube onto the surface of torus in this case, you should:

Enable Snap during transform tool with Shift + Tab. Turn on Face snapping mode, along with Align rotation with the snapping target. Switch snapping part onto the target to Median:

Grab your object (cube) to the desired place. Switch Transformation orietnation to Normal (with Alt + space). Turn off snapping and grab your cube along normals so it moves out of the base mesh surface (in my case it was Z axis):


Array modifier on parent and all of its children

Create your parent object, then create one child. copy the array from the parent to the child Ctrl-L. next take the child and add drivers to all of the parameters in the array modifier that you want to auto update. now copy the drivers and array modifiers onto all  of the other children. Done!

Using drivers is tricky, Here are some tutorials:

https://www.youtube.com/watch?v=o4qYHNA_x4Q

https://www.youtube.com/watch?v=ajMAvKRCTBg

How to copy drivers onto multiple objects


Im trying to import an stl file to edit for 3d printing, however, when i import it, the file loads as a single point

scale down to 0.001 and you will see your model. you can apply transforms by hitting Ctrl+A and selecting scale.
point: if you check dimension values you will see big values. It means blender has imported vertices but they are not in our view.


How to set up Blender for Multicore Animation

It seems like the current VSE targets in the road map do not include multithreading. That may change in the future.

The underlying issue of slow rendering is solved in this thread.


Does Blender allow to perform operations on multiple objects at once?

You are not doing inverse operation to parenting. Modifying a parameter of active object (properties display active object) only influences that object.

Operators can operate on selections, like Ctrl+P and Alt+P do.

If there is no operator to do it on multiple objects then RMB on the field > Copy to Selected. Works on most parameters in general.