It is possible to do this using a Boolean property and changing it using the toggle option, but it is easier to simply assign an integer a value. A Property Sensor set to pulse mode (to continually check to see if the value is still equal) and that activates your motion.

Blend file with working logic setup

![enter image description here][3]


How can I add a vertex at the center of a circle?

If you've already added the circle there are some other fast ways to do this:
Method 1:

Select the circle.

Extrude (E), then cancel the translate part of the extrusion with Esc.

Press ⎇ AltM > Center to merge the extruded vertices into a single central vertex.

Method 2:

Select the circle.

Fill (F) to make an n-gon.

Poke Faces (⎇ AltP) to triangulate the n-gon with a central vertex.


Is there a way to hide all the origins in the 3D view?

For Blender 2.8 and above:

You can hide the Origins for the active Objects and all Objects in the Overlay Menu.


Depends in what way the mesh is colored. Vertex colors or texture. Obj file format is officially not able to transfer Vertex color. You would need another file format to do so. FBX for example.

When the "color" is a texture, then this texture is most probably missing. Have a look that the texture is in the same folder than the obj file, and that there is a *.mtl file available. That's part of the *.obj file, and defines the material settings.

When this doesn't fix it then the path to the texture inside the *.mtl file might be wrong. Most probably an absolute path with a C:\ at the beginning. Like C:\myfolder\mytexture.png. Open it with a text editor, search for the map_kd part and change it to a relative path. Which is basically just the texture name: mytexture.png

Cycles is not able to import the texture from an obj file yet. You have to have Blender Internal renderer activated. So when the previous step also doesn't help, then simply add the texture inside Blender.


I'm trying to follow a tutorial in youtube but i don't have a bolt mesh . What should i do?

Enable the Add-on "Bolt Factory" in the user preferences.


How to exact copy paint weights from one object to another

I know this is 4 years old post but I've found a simpler solution with blender 2.82. So what I do is I copy the mesh that has three original vertex groups and arrange in the space where the 2nd mesh is meant to be at. Then rename the 2nd mesh's all vertex groups to different so it can retain its weight paint from original mesh. I used armature human rig default.


This can be done by starting from a circle instead of a cylinder.

Open the properties panel (P) in the 3d view and enable 'Length' in the 'Mesh Display' section to view edge lengths in the 3D view:

In front view, with all edges of the circle selected, extrude with E and constrain to the Z axis by pressing Z.

You can now extrude upwards and match the extrusion length with the original edge length. In this case it is 0.196. To do this perfectly you can just type whatever the edge length is (0.196) while extruding and constraining:

The last step is to add an array modifier to to create the other 'rows' of the cylinder. As long as the object has it's rotation and scale applied you can just set an offset of '1' in the Z offset field:


Animation Nodes: How to create faces from a Particle System?

Polygon Indices List

Before getting into the answer, let us first study some facts about polygon indices lists:

A polygon indices list is a list of tuples each of which include the indices of the vertices each polygon is composed of.
The order of indices of each polygon does not matter, so the polygon (triangle) with indices (0, 1, 2) is the same as (1, 2, 0), (2, 0, 1), (2, 1, 0), (1, 0, 2) and (0, 2, 1). However, the normals of the first three triangles will be the inverse of the later three, that is due to the fact that the mathematical operation used to compute polygon normals cares about the order.
A polygon indices list can not contain:

Two similar polygons, so only one of the indices mentioned in the previous point can exist in the list.
Each indices has to have at least 3 indices.
The indices should be of existing vertices, so if there are n number of vertices, the maximum index that can be used is n-1.

Generating Polygon Indices

The underlying structure used in the Find Close Points node is the KD Tree and we will be using it to generate our polygons as well. A KD Tree can provide you with the indices of the n closest vertices to a given point--Which can be any arbitrary point. If we used those indices to create a polygon where n=3 we will get the polygon indices of the triangles you wanted. if we used n=4, we will get quads and so on.

So we create a loop that takes the KD Tree that represents the vertices locations and n as inputs, a list of arbitrary vectors as an iterator and returns the created polygon indices as an output:

If we attempts to use the output directly, AN may return an error, that is because some indices might have been created more than one time, this is due to the fact that the same n vertices might be the closest to multiple arbitrary vector. So it is obvious that we have to make sure no polygon is created twice (Remember that a polygon can take multiple forms since order of indices doesn't matter).

To make sure we don't add two similar polygons, we keep track of the polygons created in previous iterations and only add the polygon generated in the current iteration if and only if it wasn't similar to any of the polygons created in the previous iterations. To keep track of the polygons already created, we create an empty polygon indices list as an input, append the created polygon and reassign the list:

Study Loops in the documentation to understand how this reassign works. We then need to check if the current polygon exist in the list of polygons we just created by appending and reassigning, this can be done by using a simple python generator:

not any(set(p) == polygon for p in polygons)

Where polygon is the set of the indices of the current polygon and polygons is the list of polygons we just created by appending and reassigning. We simply convert the polygons to sets (Because order doesn't matter, remember) and check if they are equal, If any of them is True, True will be returned and False otherwise, the not invert the boolean so that we can use it as a condition in the loop generator:

By using the condition input in the generator, we only add the polygon if all the booleans in the list is False.

And by using the loop we created, we get:

By setting the amount to four, we get quads, however, quads might not always be coplanar nor convex, so the results might be messy:

So far we have been using the vertices locations as the arbitrary vector list, and it works, but better result may come out when you use different vector lists (In my case another random vector list but with different seed):


Is it possible to remove Blender Render/Internal render?

I have searched in many places information about blender render and if I can deactivate as when you deactivate cycles or renderman21, but as far as I understand, it is not possible since its name indicates it is the internal render, and a basic and fundamental part of blender


Press K to enter knife mode, click on the first vertex, then click on the edge where you want your new vertex. Hit space when you are done, Voila!


Adding a texture to one face in Blender 2.8

OK I figured this out.

After adding a material slot and clicking new:

Click the small dot next to 'base material' and select 'Image Texture' that then allows you to load a texture for the material and can be assigned to the face.


Have you tried the Automatic weight?

Did you do the retopology?

The first time I tried doing Rig, it didn't work until I learned about retopology, wich is (im not that sure) putting less ''points''. I don't know how to explain that correctly, you should watch the video of FlippedNormal on retopology for begginer.

If you already learned about this, maybe look if you have only square, for me when I have triangles it dosen't work.

Hope it will help. Good luck


How would I go about creating a spiralled dome?

As usual, it looks as if this is simple enough to model, but the devil is in the details. Look closely at the flat space between each section, and notice how the twist is not entirely uniform either.

And I feel a non-destructive approach would be best, so that other variants of onion domes can be constructed fast.

My rendition:

start with a curve. I used the "extra objects-->Curves Galore, and used the flower:

I made some adjustments to the overall curve, and added a second circle in the same object while in edit mode (later I adjusted to this final version - it is hard to predict the exact shape at this stage):

Then I added a straight bezier profile curve, and subdivided this curve (W menu) about 5~7 times to get the resolution required for the lattice deformer at a later stage.:

Next, simple deformers are added to create a base twist and tapering (which makes it much easier to control when applying the lattice later). A taper, and a twist:

Create a lattice object. I used W:8 divisions.

apply the lattice deformer to the curve object, and start tinkering around with the size. Key ingredient: rotate each lattice sub division to control the twisting precisely.
This offers much more control than the simple twist deformer, allowing for a visually more correct twist like the one seen in the original onion domes.
Mine is a bit messy, because I was a bit in a hurry:

Done! Completely non-destructive onion dome, with a lot of control over the final result.

It literally take 20 seconds to change the profile curve, and generate quite complex bizarre looking domes:

Download the example blend here:

Addendum: adding small circles in the base curve object creates very pronounced "ridges" as seen in the original:


One potential solution is setting your normal map image node to "Non-Color Data". You should use "Color Data" only where the image's colors matter, i.e. only when connecting to a color socket.


Cannot change curve modifier after pressing 'Apply'

The purpose of 'Applying' a modifier is to make the changes that the modifier has made, permanent. Any deformation or change to the geometry a modifier may have caused will overwrite the original geometry.

As long as the modifiers are present in the modifier 'stack' (where the modifiers get listed), they will be able to be edited.

I have not followed every step of the tutorial you linked to, but unless the tutorial says to apply the modifier there is no need to. It is perfectly fine to have many modifiers on an object and never apply them, allowing non-destructive editing.

See more information about modifiers and the modifier stack in the Blender Manual.


Use Ctrl + Alt + B to clear the render border, or if you open the Space menu and type "render border", you should see the option.

There is also Shift + B, but this is the legacy shortcut for border render IIRC and it only works when looking through the camera. Use Ctrl + B as you can have different render borders for the viewport (when doing realtime rendering) and the camera.


What is the minimum size requirement for a Fluid mesh object in a Fluid simulation?

This is dependent on resolution.

Imagine the domain as a grid of 3D pixels (volumetric pixels, or voxels). If your fluid object is smaller than a voxel, then it can't be represented properly (even if it's two voxels, that's still not good)

To fix this, you can either increase the resolution (this will increase bake time), or scale down the domain (this shouldn't increase bake time, but obviously there is less room for the fluid).

Since the resolution defines a fixed number of voxels, scaling it down will give you the same number of voxels, but they will be smaller (making the fluid object relatively larger):

There may be a hard limit of how small you can go eventually, but anything remotely reasonable should be fine.


Can't create new pose library or add new poses to existing library

Looking at the screenshot you are in the object mode of the armature.

You must be in the pose mode of the armature in order to enable the button for creating a new pose library and adding poses to the library.


I assume you are having trouble with that curve. One way to create it would be to use edge loops and proportional editing. You want to make sure your cylinder has a slightly higher resolution, so the curve will be relatively smooth.

Go into edit mode and add an edge loop in the middle of your cylinder.
Select it with alt + your selection mouse button and search for checker deselect (my search button is F3). A new tab will appear, which lets you specify the offset etc. You want to only select the tips of your future curve.
Now, enable proportional editing by pressing O and hit G to move the vertices. You can adjust the editing radius with your mouse wheel and move the vertices forward until you have something that looks like half of a sinus curve.
Repeat these steps with the other half.
Now, create another edge loop underneath that looks the same by pressing ctrl + R and then E. Go into face select mode and select the curve with alt + selection button.
Extrude it and scale it inwards while locking the x-axis by pressing shift + X while scaling.


Inserting green screen footage into 3D space

Probably the best way, is to key out the green, and then import the image sequence into the 3D view.

Start by taking the image sequence into Blender, or your compositor of choice, and key out the green to your taste. Try to keep in mind the environment it's going to end up in and make sure that the key will reflect that. Then render out the frames as a PNG sequence, or any other image file format that Blender accepts that uses transparency.

In Blender, use the import image as planes addon (included by default) to import the image sequence into the 3D view. Make sure that alpha is enabled, and shadeless is checked in the settings before importing.

(You want to have shadeless checked, because if it interacts with light, it will be treated as a flat object, so any shadows that are there will be completely flat.)

Then place the plane where you want it to be, and use the color tools to make it fit into the environment properly. Or use some render layers magic to render it out separate from everything else to allow you to composite it back in properly either useing Blender or an external compositor.


"Copy to selected" dose not work with curves ? or Nurbs?

i learnt of copying through script from another post. And here is what i have changed to suit this purpose.

import bpy
active_obj = bpy.context.object

for obj in bpy.context.selected_objects:
    if obj != active_obj:
        # resolution U
        obj.data.resolution_u = active_obj.data.resolution_u
        # We could also access other proerties like bevel
        obj.data.bevel_depth = active_obj.data.bevel_depth


Facial Animations not showing up in Unity

Facial animation with combined blendshapes (=shape keys) and bones in a game engine is quite involved. You have to do quite a bit of programming combine those two things.

You can create Blendeshapes and make the animations based purely on those shapekeys directly in Unity. But you can't use bones to drive Blendshapes like you can in Blender. See https://docs.unity3d.com/Manual/BlendShapes.html

Or you can use a bones-only approach for facial animation, that would be the simplest method from a technical perspective, but it can be quite hard to do a good facial rig with only bones.


How to pass arbitrary floating-point data from Animation Nodes into a shader?

You can transfer any kind of data (float, integer, negative, greater than 1, etc.) from Animation Nodes to Shader (Material) with the help of UV Map Data Output node or Set Vertex Colors node but for this, you need Animation Nodes + Extra Nodes.

Method-1:
First, we have to find the total number of vertices for individual polygons using the Mesh Object Input node and Separate Polygons node. Then, Create Float List (the list you want to pass to the shader), and now we have to make its length equal to the total number of vertices of polygons which we can achieve with Fill List node (length = total number of vertices of polygons). Now, connect this final list to the UV Map Data Output node (Note: Create Float List's length <= Total number of vertices),

We have stored the data in UV coordinates which we can access in the material (I have added the color ramp node to show the difference between the values of the passed list),

Blend File:

Method-2:
This is also doable with Set Vertex Colors node in Blender2.81x but node-tree is more complex and slower. Here is the example, in which first I have mapped the Float List to 0-1 range then passes it as vertex colors.

Then, in the material, I have re-mapped them to back their original values with the Map Range node,

Blend File:


I assume your mesh is perfectly centered at the 3d space, you could first use ShiftS --> Cursor to center to make sure the 3d cursor is at the center of the 3d space.

Then (with the mouse pointer pointing to the 3d window) you can make the center of scaling (pivot point = little white circle) to be exactly the same as the 3d cursor by:

Pressing . on the keyboard

or

Select it from the menu

By icon of coordinates I think you mean the red, green, blue arrows, sticking out of the pivot point

To show the pivot point after moving 3d cursor:

And what pivot point at active element does:

And pivot point at median point (origin is the orange dot):

(Maybe it is a little bit too detailed) :)


Refraction quality is lower in rendered image than in the viewport preview

The problem is that you are using flat shading on the mesh, as opposed to smooth shading that interpolates normals: https://docs.blender.org/manual/en/dev/modeling/meshes/editing/normals.html?highlight=smooth%20shading#shading

The reason why it looks ok in the viewport is that your subdivision surface modifier is set to 4 iterations for the viewport and 2 iterations for the final render. So the high subdivision in the viewport hides the flat shading.

Solution: Set viewport subdivisions equal or lower than final subdivisions, and enable smooth shading on the mesh (see above link).


How to place a light inside a clear object

This is the result and the node setup:

Important: set the shader property to this: (alpha blend)

THe box needs to have transparency, so that the light can "come" out. This does the first mix shader. The second one mixes then the material of the cube with your plastic look (i just took a diffuse shader to simplify it)
a even simpler way would be this:

UPDATE for cycles:
works too
of course you have to tweak the diffuse material to your plastic material. I just simplified it.
Instead of a lamp i placed another cube with strong emission as light.


Animation nodes, instances orientation in a Dodecahedron

This method works for any object which has symmetric faces of the same size. The main idea is to align the instance object's (in your case the Tritube) any axis (local) along the edges of the base object (in your case is the Pentaface).

Note: This method required that any symmetric face of the base object should not have any cutting edge. For example, a cube object should not have a diagonal edge in any its face or in case of Pentaface object:

Step-1: A edge has a start, end, and center. So, the equation below gives the guide for start and end:

Start-Center = guide at the start
End-Center = guide at the end

To solve this for all edges, I have made a Guides for Direction Loop loop-node which takes the vertex locations, edges of the object and two empty vector lists, calculate the guides for each vertex. To simplify further, I have also made a AN-Guides for Direction group-node which automatically creates two empty lists for the Guides for Direction Loop node, so you only need to supply the vertex locations and edges:

Step-2: Then connect the vertex normals to direction and guides from the AN-Guides for Direction group-node to guides of the Direction to Rotation node:

Sometimes, you may need to rotate the instance object (in your case the Tritube) in edit mode to match the direction of the edges of the base object.

Step-3: Here is an example for cube object but same node-tree:

Step-4: I have converted the node-tree of How to call vertex groups in Animation nodes into a group-node for easy usage:

Step-5: Now, you can easily change the z-direction of instances with vertex weight but keeping them align with the edges of the base object with this node-tree:

Complete Node-Tree:

Blend File:


Remove ridges from hemisphere in half circle ngon that appear with the Subdivision surface modifier

You just need to remove the single vertex, then extrude the inner rings until you can fill the final loop with an ngon. If it's small enough, the ngon should look okay.


My Outliner and Properties editor dissapeared... how do I get them back?

Try shift +F9. Also not sure what you mean by the properties bar. Try clicking “N” if that is the one you need.


Ok, solved. You must click on proportional editing objects


Can I use Nurbs curves as the bone display custom shape?

you can simply transform your curve into a mesh (alt C) and then use the mesh as custom shape. be prepared to adjust loc rot and scale of your mesh/curve (a problem also with simple meshes)


How to make the same thickness in several places?

You could try to extrude with the Shrink/Fatten mode: Select your mesh, press altE, choose the Along Normals mode, drag the extrusion, then in the last operation box (bottom left) enable Offset Even.

(You could also use a Solidify modifier, in this case, enable its Even Thickness option)


Found an answer that fits my needs.
I made this Python script that stops the action actuator, rotates to the desired position and then plays the animation again.
I also added an always sensor to keep pacman moving on the direction defined by the "direcao" property.

from bge import logic
import math
controller = logic.getCurrentController()
own = controller.owner

name = "AnimaBocaAcao"
start = 1.0
end = 24.0
layer = 0
priority = 1
blendin = 1.0
mode = logic.KX_ACTION_MODE_LOOP
layerWeight = 0.0
ipoFlags = 0
speed = 1.0

sensors = own.sensors

if own["direcao"] == "dir":
    own.applyMovement([0,0.02,0])
elif own["direcao"] == "esq":
    own.applyMovement([0,-0.02,0])
elif own["direcao"] == "cima":
    own.applyMovement([-0.02,0,0])
else:
    own.applyMovement([0.02,0,0])

if sensors["W"].positive:
    currentOrientation = [0, 0, math.radians(90)]
    own.stopAction()
    own["direcao"] = "cima"
if sensors["S"].positive:
    currentOrientation = [0, 0, math.radians(270)]
    own.stopAction()
    own["direcao"] = "baixo"
if sensors["A"].positive:
    currentOrientation = [0, 0, math.radians(180)]
    own.stopAction()
    own["direcao"] = "esq"
if sensors["D"].positive:
    currentOrientation = [0, 0, 0]
    own.stopAction()
    own["direcao"] = "dir"

own.localOrientation = currentOrientation
own.playAction(name, start, end, layer, priority, blendin, mode, layerWeight, ipoFlags, speed)


How and where are the Python keywords assigned a syntax highlighting type in blender?

Providing syntax highlighting in the editor requires parsers for the programming languages in order to identify keywords. These parsers can be found in source/blender/editors/space_text. Currently implement are text_format_lua.c, text_format_osl.c, text_format_pov.c, text_format_pov_ini.c and text_format_py.c. Each of these implementation provides a functions to map strings to internal identifier types which can later be used to give these a distinct color, e.g. in case of the Python:

static void txtfmt_py_format_line(SpaceText *st, TextLine *line, const bool do_next)

Every format implementation provide a function to register the parser as well as the formatter. They are called ED_text_format_register_ followed by the language suffix. Ultimately they all call ED_text_format_register to register the callback functions. The registration using ED_text_format_register_ functions is performed once in source/blender/editors/space_text/space_text.c by calling:

void ED_spacetype_text(void)

Once this is completed the text can be formatted and syntax highlighted by

void draw_text_main(SpaceText *st, ARegion *ar)

which can be found in source/blender/editors/space_text/text_draw.c. This function retrieves the pointers to formatting callbacks for a given text using tft = ED_text_format_get(text);. The return value can then be used to call the callback with tft->format_line(st, tmp, false);. In case the current language is Python that would result in a call to txtfmt_py_format_line. It stores identifiers / format character in tmp which can then be used to highlight keywords by one of the drawing functions text_draw, text_draw_wrapped and draw_suggestion_list. Each of them will call the function:

static void format_draw_color(const TextDrawContext *tdc, char formatchar)

This functions contains a switch statement that identifies which format character is given and applies the matching color from the theme. For example if the format character would be FMT_TYPE_KEYWORD it would set the color with UI_FontThemeColor(tdc->font_id, TH_SYNTAX_B). The parameter TH_SYNTAX_B determines the color.

In source/blender/editors/interface/resource.c is the function that is parsing this color id TH_SYNTAX_B to retrieve the actual color.

const uchar *UI_ThemeGetColorPtr(bTheme *btheme, int spacetype, int colorid)

This function use ts->syntaxb when the color id is TH_SYNTAX_B where ts is a pointer to a ThemeSpace.

The place where syntaxb is assigned its value is in release/datafiles/userdef/userdef_default_theme.c. The value is given in .space_text as

.syntaxb = RGBA(0xff1961ff),

For this syntaxb we have a matching RNA property definition in source/blender/makesrna/intern/rna_userdef.c

  prop = RNA_def_property(srna, "syntax_builtin", PROP_FLOAT, PROP_COLOR_GAMMA);
  RNA_def_property_float_sdna(prop, NULL, "syntaxb");
  RNA_def_property_array(prop, 3);
  RNA_def_property_ui_text(prop, "Syntax Built-in", "");
  RNA_def_property_update(prop, 0, "rna_userdef_theme_update");

The property syntax_builtin can be set in the Blender theme. For instance release/scripts/presets/interface_theme/blender_light.xml sets syntax_builtin to:

syntax_builtin="#ff1961"


precisely moving faces in different directions

Click G to grab or translate the face, which you've selected and type the certain distance you want the face to go. You can use the X, Y and Z keys to lock the movement to a certain axis.


How to fake fluid in a jar while moving jar around

You can use a Surface Deform Modifier on a higher poly mesh and run a cloth sim on a low poly mesh to make it look like water, OR just use the lower poly mesh, if you don't need realism:

High poly mesh --> Add cube --> subsurf modifier level 2 and apply it--> cut the bottom half off and delete in edit mode (so you have a half sphere) --> right click in edit mode and subdivide it 2 times --> Scale on z axis until flat-ish, like top of water

Low poly mesh --> Add second cube --> subsurf modifier level 2 and apply it -> cut off bottom half again -->  Do Not subdivide more --> scale in edit mode so it's flat-ish, same shape or as close as you can get to the higher poly mesh --> align lower poly right on top of higher poly,very close

--> set surface deform modifier on high poly mesh, with low poly mesh as target -->  click bind

--> set a cloth physics simulation on low poly mesh --> make outer ring of LP mesh a vertex group with weight of 1.000 --> use that vertex group as pinning group in cloth sim>Shape>Pin group (so it doesn't go flying off the screen, lol)--> adjust weight of cloth to .8 kg; Field Weights>Gravity to .001
EDIT: try switching "angular" to "linear" in ClothSim > Physical Properties > Bending Model.  This might smooth out the physics.

--> Add empty --> add force field>Vortex to empty --> set vortex strength to 200

This should be a start, just play with the cloth simulation a little bit.
If you use higher poly, set lower poly to Not Render.

I'll come back and see if I can edit this later and maybe add a "How to" video, too tired right now.


How to hide vertices...but not object mesh...?

Quite right ..  it works the way shown in the tutorial in 2.7 with these settings in the modifier:

..but it doesn't in 2.8:

.. which I would classify as an annoyance... there's always a chance there's a setting someone knows which makes this work?


I guess one of the easiest way will be to use shapekeys, but it requires a bit of knowledge (I would personally prefer bones but it needs to know a bit of rigging). If I make it short:

Create your tree image. Save it as a PNG with transparent background. Import your image as a background, create a mesh and roughly follow the tree shape.

Unwrap your mesh, open the UV/Image editor and put the UV map over the tree image. Give your mesh a material with the image tree as Image Texture. Use the Image Texture Alpha socket as a Factor in a Mix Shader that will mix the Image Texture node and a Transparent node, so that the object is transparent.

Select your object in Object mode, go in the Properties panel > Data > Shape Keys, create 2 shapekeys. Go in Edit mode, select the second shapekey, move your object vertices to deform your tree the way you want.

Back in Object mode, keep the second shapekey selected, play with its value to make the tree move. To animate through time, create keyframes: put the cursor over the value and press i. Open the Dopesheet to move the keyframes if necessary.


The problem comes from your subsurf.
using the "adjust edit cage to modifier result" option will show you a mesh that is not the real mesh. Sometimes it helps but editing without checking the real mesh can be tricky.

In you case you have edge loops overlapping, you'll see it if you disable this option.

you can fix this by moving you edge loop away with GG (edge slide)


File browser filter not working correctly

I reported it and it turns out that it is indeed a bug. It will be fixed in Blender 2.8.

Link: https://developer.blender.org/T55503


Other than what said in above comments, you can customize the color used for unselected vertices (black by default), to whatever you wish:


"Domain Type" and other options not showing

Fluid/Smoke settings have changed depending on the version of the Blender.
If your smoke/fluid settings are different than a tutorial, get the exact version, the tutorial is using.
You can download any (even the oldest) version of Blender on their download page.


Material Preview as default viewport shading

Open Blender, switch to Material preview, go in File > Defaults > Save Startup File.


Set active 'Scene Collection'

scene_collection = bpy.context.view_layer.layer_collection
bpy.context.view_layer.active_layer_collection = scene_collection


Set background color: always black despite horizon color?

If you would like to view the background in the viewport, in the Properties Tool Shelf (Shown by pressing the "N" key) and under the "Display" tab, check "World Background"


What is the best workflow for dealing with modifiers and complex objects?

For bending an object (yeah, it's simpler if you combine all into one), you can use Mesh Deform modifier.

Make the cage around the car, simple box with subdivisions. Make it wire viewport visibility
Add the Mesh Deform modifier to the car and select the box and bind
Put Simple Deform modifier to the Cage object, or some other modifier


Solved it. Apparently the "fix" on youtube I had did copying opengl into the blender folder was messing it up


My first guess would be that you're trying to do parenting in Pose mode. Switch to Edit mode on your armature and you should be able to parent bones without problem.


Arrows do not appear at selected point on mesh

Disable "Adjust cage" option

Bender is capable of showing the result of some modifiers in edit mode. Subdivision surface & Mesh deform are one of those. In addition there is also an option called Adjust edit cage to mesh result; from the Blender's reference manual page:

  This lets you grab the vertices as they lie in their new smoothed locations, rather than on the original mesh.

Despite this, the 3D manipulator will stay stiched to the un-adjusted cage of the mesh, creating the small gap you mentioned.

In your case the modifier causing that is the last: Mesh deform.


How can I import BI materials from another blender file with python?

There is some archaic way you could do this with bpy.ops.wm.link_append() but a better way is to work with the api available via bpy.types.BlendDataLibraries.

import bpy

# using a relative path
path = "//file_name.blend"

with bpy.data.libraries.load(path) as (data_from, data_to):
    data_to.materials = data_from.materials

As a sanity check or for logging purposes, you can loop through what was appended and see if everything is there as it should be

for mat in data_to.materials:
    if mat is not None:
        print(mat.name)

As it relates to many files, it should be simple enough to extend the script to also loop through a list of filenames to append materials from. A final note, the materials appended have no users so make sure to stick them somewhere before closing your file.


How to disable vector pass calculating on unwanted frames?

To use vector information for frame 10, information from frames 9, 10 and 11 are used. This make sense, because to get a sense of speed, Blender needs to compare the positions of objects before and after the current frame with the position in the current frame.

Lets say that you want to use vector info for frames A to B. Is it the case that you get weird results for frames A-1, A, B and B + 1 only? In that case I would simply manually re-render those frames with the vector checkbox ticked.

It might be possible to use a math node in the compositor to automate the
influence of the vector pass in your node setup, taking 0 as the input to the vector pass node for the frames I mentioned and the actual vector values for the other frames


When exactly __init__() of bpy.types.Panel subclass must be executed?

The ____init____() function for BPY types (especially UI stuff) can be unpredictable and should not be used.  You likely want to be overloading the draw() method instead.

Example:
http://www.blender.org/documentation/blender_python_api_2_57_release/bpy.types.Panel.html


Associate one emitter with a specific curve

To ensure that particles from an emitter are following a curve guide force field do the following:

Make a simple emittor object e.g. a cube
Change to edit mode, select one vertex and add this single vertex to a vertex group
In the particle systems tab, scroll down to Vertex Groups and select the vertex group with the single emitter vertex - this will cause the particles to be emitted from just this one vertex
Place the emitter vertex close to the curve guide path
(Optional) Adjust the force field settings to control the effective distance of the field (to avoid overlaps with other fields)
If you need multiple emitters and paths you can parent the emitter to the path and duplicate as needed.

Setting this up, can be a bit tricky sometimes, since it can happen, that particles drop out of the force field, but with a bit of fiddling it can be done.

I used this technique to create the arrows in this video: http://rheologic.net/en/urban-wind-assessment#wind-effects


Blender 2.80 requires AMD graphics card with at least GCN first generation architecture. The Radeon HD 4770 has the old Terascale 1 architecture and is therefore not supported.


Those purple lines are normals generated by Auto Smooth. It has checkbox under the Object Data tab > Normals rollout. I would recomend you just turn that feature off. If you want some complex shading, you should generaly use Sharp Edges with an Edge Split Modifier.


I've started with a simple scene, and this node setup (a standard diffuse is currently connected so we can see the default lighting effects)

If you connect the other node setup, you might see something like this, depending on the placement and power of your lights (Note: make sure alpha blend is enabled for the shadow catcher material);

Say you've adjusted this multiple value, but the shadow is too light;

Move this slider up...;

And turn up this value;


How can I create a silhouette using HDR in cycles?

A silhouette means that the light coming from the camera side of your object is not as intense as that of the background by a large ratio. Bringing down the intensity of the image used in the environment can help you bring down values on the foreground object as well.

There are several ways to adjust the exposure for a scene

Use the strength slider to adjust the exposure on the HDR, this will allow you to adjust the HDR environment without affecting any of the intensity of other lights on the scene:

A different way to do this is to Change the exposure for the whole scene on the Film>Exposure section. Changing the exposure will affect all of the elements in the scene:

Or you can also change the exposure value on the color management section:

If you use the compositor (which is not only not a hack, but it is your very best friend, as it can be a powerful tool) you can use one of the many color correction tools available in it, in this case the ASC-CDL node is the best tool for the job.

The main advantage of this approach is that you can alter the relationship between the bright and dark information of the scene. Not only you can change the exposure making all of the image brighter or darker, but if you you modify the power you will affect the ratios (or contrast) of the scene, giving you much more nuanced control on the final result.

You can even decide to keep a bit more detail in the highlights and the shadows:


You could run Blender through PHP, pass arguments (see here) and let Blender print JSON-encoded data wrapped by some text markers. Extract and parse the JSON-data with PHP and use it.

Example implementation:

https://github.com/CoDEmanX/blend_stats

Note that Blender.Window.FileSelector(...) is only valid in Blender 2.4x, API is completely different in 2.5x / 2.6x.


ok, i made a "quick and dirty" example, how to do it.
Result:

add a plane on ground -> passive, collision (gray)
add a rigid body (active) on it (green)
add a plane, which does NOT collide with other meshes when you place it
3b) at lots of subdivision surface to plane, but not too much, else your computer explodes
add cloth modifier to plane, fix it with a vertex - pin group
raise qualitiy collisions to 20
add solidify modifier to plane with thickness -> apply
check object- and self collision
increase your outer thickness of your rigid body
let the other settings of cloth as they are -> little changes in the properties change a lot for the simulation

here is my blend file to check it out:


There are many tools used for mesh modeling that you can use, the simplest to get you started is probably the knife tool.

In edit mode press K and then click where you want to corners of the new face (also called a polygon) then press ⏎ Enter to confirm the cut or Esc to cancel. During the cut you can press C to help keep your lines straight.

Some other tools used for modeling are the loop cut and subdivide to split a face into multiple faces. You can also add single vertices and make a face from 3 or more unconnected vertices, it is easy to find beginner tutorials on mesh modeling.

Note that simply cutting a face into another will leave you with an n-gon, which is a face with more than four sides (compared to tri or quad faces). While n-gons can be helpful during the modeling process, as you progress you will find times when they can cause issues. It is always recommended to maintain a quad based mesh as much as you can. In your example that would mean adding at least another two edges.


Exporting to OBJ with textures not working properly

You are using Cycles materials, the exporter doesn't support exporting textures from node based materials.
Since Cycles is acting as the active Render engine the materials you created are for the Cycles renderer, and hence use node based definition. The obj exporter can't read these materials nor find textures used in them if any.
Set Blender Internal as Active render engine, redefine your materials, and reuse desired textures.
Also see .fbx export why there are no materials or textures?


creating more randomness in texture image

In general for image texture randomness you need to offset texture in X, Y axis for each object. For that you will need also seamless texture to prevent edge texture appearance.
Random Location
One way to randomise location can be done with Object Info node > Random plugged into Mapping node > Location

Random Color
similar way you can be randomise a color of tiles

Random Rotation
... you can randomise rotation as well, but directly connected Random to Rot cause "shearing", because texture would be rotated in all axis. To prevent this result use Separate XYZ node and Combine XYZ and connect only Z axis. To rotate more or less you can add between Math node and increase or decrease value.)


How to copy objects and set their origins with Python console?

The reason all of them use the same location is because you are leaving them all selected.
bpy.ops.object.origin_set(type='ORIGIN_CURSOR')

will set the object origin to ORIGIN_CURSOR for all selected objects.
Add:
new_obj.select_set(False)

as the last line in your for loop.


Sculpted with Multiresolution, enable Dynamic Topology wrecks mesh

The Multiresulition modifier simply does not work with dynamic topology.

When you try to enable dynamic topology with a Multiresulition modifier on the mesh you will get a warning message like this:

  Warning!
  Generative Modifiers Detected!
  Keeping the modifiers will increase polycount when returning to edit mode.

Also if you hover over the modifier you will see this error message.

  Not supported in dyntopo

You have to apply the modifier before using dynamic topology.

The only way to "rescue" your sculpt now is to go back to a previous save, before you enabled dynamic topology.


How can a grid mesh be unwrapped to overlayed quads?

Starting with an unwrapped grid (without the joints), press U in Edit Mode to bring up the unwrap popup and chose Reset:

After scaling down all UVs to the size of a single tile they can be distributed by repeated Random Deselect from the Select Menu in Edit Mode


Look at it in Front View (Ortho). Note that with the rig you have it is designed so it will fold into a square, ignoring the end pieces. If you want something else like a pentagon maybe you should start with that shape and work backwards unfolding it. Or just change the shapes of the end pieces to be more like the rest.


Face reflects light differently to others

This is a problem related to the normals.  To correct it, go into edit mode and select everything. (This can be done by pressing A once or twice.)  Then, click Shading/UVs > Normals > Recalculate.  If this does not work, select the single face and click Shading/UVs > Normals > Flip Direction.


Advice on dividing and unwrapping this mesh

To improve the shading:

either check ✓ Harden Normals in the Bevel modifier.
or slightly inset the area

FunFact: I'm not quite sure why this helps, it'd be great if someone explained it in the comments :)


I found the answer!!
The problem was that the solidify was not enough strong, so the donut part was breaking through. For fixing I increased the thickness


Two ways that seem to work

Glass Shader with a Mesh light inside

enable Screen Space Refraction (in render tab and material setting)
set refraction depth to a non-zero number (to fake the glass thickness)
I used a musgrave texture to fake uneven light intensity

Translucent BSDF shader, with a Point light inside.

nicely simulates different thickness and light intensity
just keep in mind, that Eevee is limited to 128 lights per scene

Glass button with a Mesh light inside

Translucent button with a  Point light inside


Is there a way to move the sculpt tools (grab tool for example) away or towards the user?

Consider

Quad View so you are seeing both front and side views.  Or you can open 2 edit windows to get the exact views you need by rotation of view.
Sculpt Draw Brush with Add selected as depicted in the image above.
Click in the same place on mesh.  No lateral movement is needed.
To emphasize you are only clicking an area with no movement of cursor.  The area grows toward you the viewer, which is difficult to see.  You see the growth in the profile view. You are creating a protrusion directly growing towards you.  You may click in Top Ortho and see growth in Right Ortho.  Create change in one view and see it in another view.


Wondering about an efficient way to mirror specific parts of a mesh

Enter Edit Mode and select the faces you want to mirror. Press P and choose Selection to split the faces into a new object.

You can then apply a Mirror Modifier to the new object.

Remove the X axis toggle and apply the Z axis instead:

At this point the new object will be mirrored around its point of origin, which it inherits from its original object. This might be in the wrong position and your mirror may be in the wrong place like this:

You can fix this by updating the objects Origin. The easiest way to do this is to first select the Parent object. Press Ctrl + Alt + Shift + C and select Origin to Geometry:

Next, with the parent object still selected, press Shift + S and choose Cursor to Selected.

Next select the Mirrored part and press Ctrl + Alt + Shift + C and select Origin to 3D Cursor. This will set the Origin for the Mirrored part to the same position as it's parent part and your mirrored mesh should appear in the right place:


How to delay all keyframes to make space for a new animation scene?

To solve your problem, you can select all (animated) objects in your scene, then select all keyframes that you want to move, and hit G to translate them further ahead.
To prevent this problem in the future, I suggest splitting your animation into shorter sequences, but this is case specific, not useable for when you want to extend the scene.
Since I don't know what exactly is going on there, I can only suggest.


Tiny GUI buttons and text on high resolution monitor

Steps ...

Go to User interface
Navigate to the System tab
Under General Section tune DPI value to fit your need.

No more issue with having a fancy 4k screen ... cheers.


How would I go about turning this object into a 3D model with the same colours?

It's not easy to turn a 2d image into a 3d object.  What I would recommend is to create a "turnaround" as a first step.  Basically this involves sketching a front, side, top, and/or back view of the character.  An example is here.

This is very important to figure out the shapes of the model from multiple angles.

Once you have the turnaround, you can import it as Background Images in blender and assign it to the front and side views to use as a guide.  From there model on top of the images.  There are many tutorials for that kind of modeling, like the famous Joan of Arc Tutorial.

Good luck!  The turnaround sheet is likely the hardest part.


Why doesn't extruding from some edges make a face while usually it does?

Can you confirm that you select the connected vertices rather than a duplicated one?
You can use indices indicator to show the vertices. Than you should check which vertex you choose to extrude. If you select two separated vertices, they won't automatically connected with face and edge since it is impossible and unusual.

You might accidentally exit the extrude mode with RMB, it will create the vertices in the same place. Causing extra vertices that user might not noticed.


UV mapping in viewport is different from render?

Meshes in Blender can have multiple UV coordinate sets.

The one selected (blue background) is the UV map used in textured mode. The one with the small camera icon activated to the right is the default UV map used for rendering.

If your model has multiple UV maps, either click the camera icon of the map you want to use for rendering or select the map by its name as an object-attribute in the node editor:

You can find the Attribute node by pressing [Shift+A] and selecting Input->Attribute in the node editor.


How do I run an existing add-on via the python API?

Addons register panels and operators

An addon when enabled registers panels and operators and properties etc it uses. An operator, or set of, is generally the means an addon uses to "run".

The addon tells us where to look for the operator in the UI, in this case object menu > quick effects > Cell Fracture.  With developer extras turned on will see the operator is bpy.ops.object.add_fracture_cell()

To the python console.  What's important here is the module name, using code from question

>>> for mod in addon_utils.modules():
...     if mod.bl_info['name'] == 'Cell Fracture':
...         mod
...
<module 'object_fracture_cell' from '/home/batfinger/blender-git/v2.8/bin/2.83/scripts/addons/object_fracture_cell/__init__.py'>

To enable the addon

>>> addon_utils.enable("object_fracture_cell")
<module 'object_fracture_cell' from '/home/batfinger/blender-git/v2.8/bin/2.83/scripts/addons/object_fracture_cell/__init__.py'>

Note this pretty much calls the modules register() method. and could also be done via

object_fracture_cell.register()

Inspect the module. Could eyeball this, via code or UI as described above.

Similarly to https://blender.stackexchange.com/a/163366/15543 instead of panels will look for operators

>>> for p in dir(object_fracture_cell):
...     x = getattr(object_fracture_cell, p)
...     if inspect.isclass(x) and issubclass(x, bpy.types.Operator):
...         x, getattr(x, "bl_idname", "None")
...
(<class 'object_fracture_cell.FractureCell'>, 'object.add_fracture_cell_objects')
(<class 'bpy_types.Operator'>, "None")

>>>

Telling us that cell fracture has one operator

bpy.ops.object.add_fracture_cell_objects()

Autocomplete gives us the arguments available to the operator

>>> bpy.ops.object.add_fracture_cell_objects(
add_fracture_cell_objects()
    >>> bpy.ops.object.add_fracture_cell_objects(
add_fracture_cell_objects()
bpy.ops.object.add_fracture_cell_objects(
        source={'PARTICLE_OWN'},
        source_limit=100,
        source_noise=0,
        cell_scale=(1, 1, 1),
        recursion=0,
        recursion_source_limit=8,
        recursion_clamp=250,
        recursion_chance=0.25,
        recursion_chance_select='SIZE_MIN',
        use_smooth_faces=False,
        use_sharp_edges=True,
        use_sharp_edges_apply=True,
        use_data_match=True,
        use_island_split=True,
        margin=0.001,
        material_index=0,
        use_interior_vgroup=False,
        mass_mode='VOLUME',
        mass=1,
        use_recenter=True,
        use_remove_original=True,
        collection_name="",
        use_debug_points=False,
        use_debug_redraw=True,
        use_debug_bool=False)
(undocumented operator)

In lieu of usng documentation link, while migratory


How can I create a border around a cylinder mesh that protrudes forwards

How is the face of the cylinder filled? If it's filled with a triangle fan (single central vertex) then you won't be able to add an edge loop. One way to add one is to duplicate the outer circle of vertices and build a ring off of that by extruding it inwards to make it solid then extrude those faces outward to give it depth.


Efficient way(s) to render point clouds of 3D scan datas in cycles

May be you want to check out this link to render a colored point cloud in Blender-

https://visheshvision.wordpress.com/2014/04/28/rendering-a-colored-point-cloud-in-blender/


Can't find the Modifier section in Strip properties to use curves

The reason why is simple, this feature is not in Blender 2.62. I wasn't able to find the exact version it was added but looking at the videos. I would say any version 2.68 or higher will have strip modifiers.


Why are these red dots appearing in my viewport?

The red dots are appearing because of Subsurface Scattering (SSS), or translucency. When you turn on SSS in Cycles, there will be strange colored dots unless you render at a higher sample count. Some possible ways to solve your problem are

Reduce the amount of SSS by adjusting the Subsurface slider.
Adjust the Subsurface Raduis

Because doughnuts are usually made of bread, you should have SSS values close to 0.05, and SSS Radius values close to (0.1, 0.1, 0.1)


In the picture below, you can see the effect of extra edges placed where you need a surface to keep its shape, that is, have sharper corners or edges.
The bottom row has a smoothing modifier on it.  So you have to cut more edges (or use Loop Cut as edna said), where you need an edge or corner to be sharper.


Blender UV Problem: Unwraped UV Size different in UV Editor and 3D View

If you don't tell the material to use your UV map, it will use "generated" coordinates by default.


Sure thing ! Just after adding your primitive, type F9 or open the foldout in the bottom left of your screen.

It will remember the setting for this kind of primitive in the file so next time you add a cube for example the box will be unchecked.


Why is my Xerox font degrading in appearance in Blender?

Fonts are known for topology issues and this one is, too, incontinuous (see below)

Maybe Blender has problems qualifying it as a separate object or a hole or yet something else and hence the incomplete filling.

One way out of this is to make the logo in an external app and import it as a plane to Blender. Then, just set the camera to ortographic, add proper world color and you're done.

Or, if you want to do some more Blender work, use it as a background image for your model.


Boolean Modifier not working with Solidify Modifier

I would do two things to try and fix this. Firstly, you can try switching the order of which modifier is first.

Also, I'd try playing with the "offset" in the solidify modifier to see if that fixes it


Need help figuring out how to fix this non-manifold 3d print

The Face on the side of your mesh shows a N-Gon (Face with more than 4 Vertices). You should make sure that you only use quads (and tris if necessary) to get a good edgeflow to work with.

See if you can fix that by Hand (K is shortcut for knifetool, so you can insert edges manually) and when you're done you can also use Blenders Cleanup Function. Go to Edit mode, select all faces and go to Mesh (in the 3D viewport header) -> Cleanup. There you'll find a few options to cleanup other nonmanifold geometry like lose edges or double faces. It has Tooltips if you hover your mouse over it.

Hope this helps you, Happy Modeling :)


How to move multiple objects in relation to central point

In the header of the 3D window change the pivot point from median point (default) to "individual origins", then select all objects and scale.


How can I light an object for a turntable animation?

One method is to add multiple spotlights surrounding the scene:

Since World light comes from all directions, Another method is to change the world color and increase the World light strength:

You can also experiment with different types of lights and angles to get the results you are looking for.

Here is the Wolrd lighting + 4 point lights plus a 3d mesh put in the middle:

Each light is 150w and the world lighting is pure white with a strength of 0.4.


The object you're trying to move is the Meta Rig and it will not move. It's just used to generate the final rig. You can hide it or even delete it. Then you could unhide layer 29  in your final rig (see image). This will show the deforming bones which are very similar to the Meta rig bones.


You can achieve this effect by using the dynamic paint system. Select your steel plate and give it a dynamic paint physics modifier, set it to be a canvas. Then set your laser object to be a dynamic paint brush. Add a wetmap output at the bottom of the canvas settings.
Now in your shader settings you can get a vertex info node and set import the wetmap data. Plug this into a principled BSDF in the emission strength settings and make sure to add a blackbody node into emission colour for the correct colour. Then just mess around with the spreading dissolving and shrinking paint effects until you get the look you want.

You can download an example of the effect I think you are going for with this blend exchange link.


How to get x,y,z location from a list with python?

Assuming we have the default cube and three clones as our object names, we can build new lists for the locations, and the Y locations. You asked for both in the question and I was unsure which you actually wanted...
import bpy

list = ["Cube","Cube.001", "Cube.002", "Cube.003"]
locations = []
yLocs = []

for n in list:
    locations.append( bpy.data.objects[n].location )
    yLocs.append( bpy.data.objects[n].location.y )

print( locations )
print( yLocs )


Only one object at a time can be UV-unwrapped (except when using an add-on like Texture Atlas). When this is done, the mesh datablock for that object gets a UV Map assigned to it.

If you want to UV map that whole structure together, you can first select and join the multiple mesh objects (CtrlJ).

When you do this the mesh pieces will all become one object, and take the name of the object that was selected last. This last-select object is called the Active Object, and notice how its selection color is a little bit different from the other selected objects.

You might consider leaving the door as its own separate object, since it may move, or you can have it all as one mesh and still animate the door by rigging it. But you haven't mentioned animation so I'm getting ahead of myself. Anyway, the idea is to organize your mesh data into larger, easier to manage objects.


Procedural Vue-like materials with Cycles

I would say yes.
Here is an example I made in a few minutes entirely with material nodes:

Node setup:

Note that the color ramp near the bottom of the screenshot is going from 0 to 3 (to make the displacement stronger). To make colors darker or lighter than 1 or 0 you must type the values in directly.
Also note that the above image is rendered with Cycles experimental displacement.
To enable this you must enable experimental features in Properties > Render settings > Render > Feature Set:

This enables the Displacement settings in Properties > Object Data.


Steps for creating the below image:

take the default cube
add a subdivision surface modifier set to simple, with 7 levels
add a displacement modifier and choose your image texture, adjust strength so it doesnt displace it too much.

The actual engraving gets done with the displace, where you select Image Texture, and then use whatever image you want. However, displacement acts only on the existing geometry, so you need to make sure your mesh has enough detail to apply the texture to. To solve this, I have a subdivision surface set to simple (so it doesnt change the geometry) added before the displace:

I hope this is what you're looking for.


It looks like all I was looking for was to find and edit the dimension property (press n)


Why is mesh.from_pydata resulting in segmentation faults?

The method from_pydata appears to be surprisingly brittle for something in Python. Something as simple as using a vertex index number that is out of bounds (number higher or equal to the number of vertices) will result in odd results followed by a segfault shortly after (for example by going from object mode to vertex mode).
Calling validate should at least prevent a segfault from happening. You'll have to look for what is exactly invalid with your parameters when calling from_pydata):
my_mesh.validate()

Edit: I spent a bit of time chasing segfaults with from_pydata myself until I eventually found reports such as the ones below. I don't imagine the use of it without validate since segfaults taking the whole process down are quite annoying.

https://developer.blender.org/T32773
https://developer.blender.org/T50199


You cannot animate directly in Edit Mode but you can make hooks that allow animation via Object Mode. You can do the same for edges. The hotkey is CTRLH


Is there a way to auto-save generated python code in Blender?

An Addon

There have been some attempts (notably: Macros Recorder )
to make an addon that can record the commands to a textfile. But nothing built in like you might be familiar with in programs like ZBrush, which lets you record a session from start-to-finish.

The info log panel itself

You'll find a lot of repeated commands, and some ommited commands, and some commands that won't work when purely executed from a Text Editor. So even if you get all the output saved, unfortunately, I don't think it will do what you want.

Copy them to Text Editor

You can store a massive amount of data in bpy.data.texts, which you can access from Blender Text Editor. When saved that data will persist in the .blend until you manually delete it.

With the mouse cursor inside the Info panel and when you have the desired lines selected:

copy them to clipboard ( Ctrl + c )
open Text Editor, press + on the UI to create new Text File
Paste ( Ctrl + v )
Help your future self by giving the text file a good name.
save the .blend

If all you want to do is get an idea about the operators you called during the modelling process, then I think those steps are the literal answer to your question. I don't recall seeing an addon that does that, so I made one.


Stretched texture with Principled texture setup

The shader uses UV map of the object if it is available.
If you modifiy the object mesh after the UV map has been defined (and base objects have a default UV map), then Blender can't guess where to place the UV part of new geometry or how to move the already existing one of changed parts of the mesh.

And as result,the UV map part of these new faces are flat:

So to solve it, depending on your case, you can either make the UV map again, or change the texture coordinates in the shader.
Here for instance, "generated" texture coordinates and the image texture changed to "box":

The documentation of the texture coordinates node here.
And some practical information about it from Blender Guru here.
In case it is useful, a UV map is a map that defines the correspondence between 3D faces of the model and 2D parts of these faces on a texture.


How do I achieve this look for the viewport?

You do this using the solid view settings. They can be accessed in the dropdown menu in the top right corner of your screen, as shown in the picture. Copying the settings I use gets it pretty similar to the picture you posted.


Any bubbles simulation + Eevee Tutorials?

I was able to figure out the basics and take it from there… (hopefully it will help someone).

Basic Settings, as in Barebone settings

Requirements:

Domain - This is the container where the simulation will happen.
Use a cube, adapt it to the dimensions of the simulation. E.g. if it is for something that will float or elevate (like smoke) then a vertical rectangle would do.
While the cube is selected, go to the Physics Properties tab from the Properties right panel.
Enable Physics for: Fluid, type: Domain, Settings: Domain Type: Gas, everything else stays untouched for now.

Force Field - Inside the cube, at the bottom add a plane. While the cube is selected, go to the Physics Properties tab add a Force Field to it. Type: Wind, Settings: Shape: Plane, Strength: 0.700, Flow: 0.500, everything else stays untouched for now.

Particles Emitter - Inside the cube, above the Force Field plane, add a 2nd plane. While the cube is selected, go to the Physics Properties tab. Fluid, Type: Flow, Settings: Flow Type: Liquid, Flow Behavior: Geometry, everything else stays untouched for now.
Also add a Particle System to the same plane - From the tab above, the Particle Properties, click the “+” sign in the upper-right corner to add it. It will be called “ParticleSettings”. Keep it as an Emitter. Change the Number of particles to whatever suits your simulation. Emission/Number: Default is 1000. I had enough with 100. Check when you want them to end, default is at the frame 200. Check for how many frames they will live, default is: 50 frames. Cache (Optional, if your RAM can afford it): Cache Step: 6, this will smooth the simulation. Rotation (Optional): checked, Randomize: 0.5.
Physics: Newtonian, Mass: 0.5.
Multiply Mass with Size: checked.
Default shape of particles is Halo (little spheres). To change it to an object of your choice: Render section of the same tab, Render As: Object, Scale: 1.000, Object, Instance Object: “your obj here”.


How can you use one object to delete the same 3d space on another object?

As Christopher Bennett says, if you use Boolean modifier / Intersect mode it will work fine:


How to export a camera animation to Houdini?

Alembic files are the way to go.
Just export from Blender by going to File > Export > Alembic and import it in Houdini with File > Alembic Scene.


How to make a simple mask like in Hitfilm?

You can use Set Alpha node(In Converters) and as an Alpha input use the mask. You can also use Alpha Over node with Alpha 0 background input and your image "over" input, but that leaves sometimes ugly rim, so the first option is better in most of the cases.


How do I get proper reflections (Eevee)?

By default, Eevee will reflect the HDRI and the lights but it won't reflect the objects of your scene.
For reflective volumes, you need to create a Light Probe > Reflection Cubemap in order to reflect the object(s), as explained here by Tutor4u. It's a kind of trick to recreate a proper reflection.
For flat surfaces like mirrors you have other light probes: Reflection Planes,  much easier to handle, you don't need to bake and it will reflect in real time so you can animate. Just make sure that the light probe is a bit shifted so that it reflects correctly, and that the mirror object has thickness, or Backface Culling enabled.
For a volume, here is a Suzanne, I gave it a Glossy node, it reflects the world HDRI and the lights but it doesn't reflect the objects (here the checker ground):

In order to make Suzanne reflect the objects of the scene you need to create a Light Probe > Reflection Cubemap that contains her. It acts like a scanner that takes an image of the environment and projects this image on the surface of the reflexive object(s) that it contains.

First, put your cursor on the exact same point as your Suzan and create (ShiftA) the Light Probe > Reflection Cubemap. In the Properties panel > Object Data tab you can choose the light probe shape: Sphere or Box. In your case choose Sphere and stretch it a bit so that it adapts to the car shape.
Go in the Properties panel > Render > Indirect Lighting, click on Bake Cubemap Only button, enable the Auto Bake option so that you'll see all the changes you'll make in the settings in real time. Actually in my case this option doesn't seem to work so I had to re-click on Bake Cubemap Only to check any change.
Keep the light probe selected, go in the Properties panel > Object Data tab, in Viewport Display enable the Clipping option, and in Probe, set the different parameters :

Clipping Start determines where the scan begins, the Clipping Start dots must begin just outside the geometry of your object (otherwise the scanned image will be black as it begins inside the object) but as close as possible (as it is supposed to scan the object environment, it must not miss an object that would be too close to the reflective object).
Clipping End determines how far the scan must go. If an object is beyond the value, it won't be scanned and therefore it won't be reflected.
Radius will determine how large the light probe is, if it's large enough to contain several reflective objects, it will influence all these objects, meaning it will project the scanned image on all of them. It might be ok in some cases but it can give bad results as objects being contained may not reflect each others (yes because the image that is projected is the scan made by the light probe, not the real reflection produced by each object). In that case create as many light probes as you have objects.
The Falloff will determine the decrease of this influence. For example if an object is in the area between the Radius and the Falloff, you'll see that the reflected image will decrease along this area.

Nota Bene: The reflection won't be automatically refreshed when you move an object, you'll need to recalculate. It means that if you animate an object you will need to calculate each frame.
The Light Probe > Irradiance Volume as nothing to do with reflection, it is used to bake the indirect lighting.


Why is this surface red? Is it because of the lighting?

It looks like you have sub-surface scattering turned on for the walls (or maybe another object)in your room. Look through all your materials and check that it's turned to 0 (if that's what you want).


Select the text and copy it, then paste it into a text editor and save it as something like Add_mesh_round_cube.py (make sure to give it the .py extension).  Now you can load it into Blender like any other addon.  Open the User Preferences (Ctrl+Alt+U) and go to the Addons tab, then hit Install From File and select the file from your computer.  Then click the little checkmark next to it to enable it.

Note that, as others have mentioned, the specific addon you are looking at is already bundled in Blender by default, so you can just find it in the list and enable it.


How make particle objects follow z axis while also following the ground?

The particle system uses the normals from the mesh to grow the 'hair'. So, if you want to make all the particles grow upright and follow the terrain, what you should do is:

Create another mesh above the terrain (as simple as possible, like a
plane, or circle)
Subdivide it a few times
Use a Shrinkwrap Modifier on the new mesh, so it follows the
terrain, at the same time preserves the normals pointing upwards
You may use Wrap Method as Nearest surface point and Above Surface, but you may try other methods if you like
Make the particle system on this new mesh; (on the modifiers list,
the Shrinkwrap must be above the particle system).

This way your grass will grow upwards, and the roots will follow the terrain.


Tweaked three things and got it to work.

Tris to Quads

The first thing I did was Tab into Edit Mode and key Alt + J to convert Tris to Quads. This is a form of retopologizing that is highly recommended. Triangles are not recommended when modeling.

Remove Doubles

I keyed W to open the Specials menu and selected Remove Doubles. This got rid of excess duplicate vertices that were messing with your Weight Painting. Of course, this destroyed the shading, so I added an Edge Split modifier in the Properties panel > Object modifiers tab.

Parenting

After all the changes to the mesh, I redid the parenting. I selected the mesh, then selected the armature, keyed Ctrl + P, and chose Armature Deform > With Automatic Weights.

Here is the fixed .blend file:


required amount of light is not coming inside the room

You can use whatever strength value for the environment that works for you, so if 20 is too dark, you can use 200, if 200 is too dark, you can use 2000, so if there is not enough of light, just add more light.
One thing to keep in mind is that if you have glass windows, whatever light comes through them, becomes refractive caustics, and they are terribly slow to calculate and not accurate at all in Cycles. You should consider using fake glass shader with transparent shader mixed with glossy for reflections by amount determined by Fresnel node. It might be a good idea to avoid calculating shadows from the glass at all, because they practically do not contribute to the realism of the render at all in vast majority of cases, so you can have the glass of all the windows as a separate object and disable it's visibility for all rays except camera rays:

What's important in lighting is not the numerical values, you use, but their proportions compared to each other. The light of the sun on a clear day might illuminate the ground with 120 000 lux while artificial lighting on a desk in an office is required to be(and often is) around 200 lux(at least where I am). So that's the difference between a light bulb and the sun in reality... Keep that in mind. In a dark painted room like yours the difference between the inside and the outside would be huge as well. No need to be afraid of that. If you have the values their relationships in the scene set up the way it is not convenient for you to adjust the strength of the environment and keep the ratios, you can also adjust exposure here:

... or here:

Both are OK, the first multiplies the values in the rendered result, the second multiplies the values of all the lights in the scene if I am not mistaken.
You should use portals to speed up the render - the noise clears up faster if you use portals, but they should not have any influence on the looks of the render.
Note that you definitely do not need any add-ons whatsoever to have nice light in your scene. They might make it more convenient for you to set things up, but are completely optional.
Here is an example of how I usually set it all up(.blend file (134.03MB)). I hope that might be useful to have a look. Feel free to use all assets in the file under CC0 license if you wish.


Why do I get an indent between two objects after adding a Subsurf modifier?

It's just bad topology, you have ngons that are stretched by the Subdivision Surface modifier, use the knife tool and create edges on the top to only keep quads:


Render suddently coming out black in Blender 2.91

Check your Scene settings, you've chosen your house as Camera, select your camera instead. Selecting another object than a camera may be useful sometimes to see what an object is pointing towards (for example select a light and press Ctrl0):

As for the light, it's your world that lights up your object, open a Shader Editor, switch to World and see, you have a Sky Texture plugged into the Output.

If you don't want the world to light up the scene you can unplug its nodes or play with its Ray Visibility settings:

Edit: Additional edge loop in order to sharpen your roof (but Subdivision Surface modifier doesn't seem necessary here, it is supposed to round the shape with virtual subdivisions):

To get a proper displacement for the material called Pantiles you need to unable Material > Settings > Surface > Displacement > Displacement Only. But as your topology is not very good the Subdivision Surface modifier subdivision won't be very good either, you'd better rework the topology a bit so that it is made of regular square faces:


Move object along local axis with Python API

Turns out having constraints on object is relevant – cannot use matrix_world for applying transforms. Instead use matrix_basis, to get access to location, rotation and scale, before constraints and parenting are applied.

Following code will move object along it's Z axis:

from mathutils import Matrix

loc = Matrix.Translation((0.0, 0.0, 1.5))
ob.matrix_basis *= loc


You can easily rotate the view by pressing the middle mouse button and moving the mouse. To pan the view, do the same but also maintain Shift. To zoom in/out, do the same but also maintain Ctrl (or simply use the mouse wheel).

You can use the numpad keys to set the view to :

front 1, back Ctrl+1
right 3, left Ctrl+3
top 7, bottom Ctrl+7
camera 0


How to get to FCurves from specific strip?

I will wait few days before accepting my own answer. Maybe someone else will have a better
idea.

Due to lack of other answers and request to do so I will give what I am currently using.
I still feel like it is not the best approach, but it as well may be (I don't know Blender's API that well, just started learning).

I've created an operator that takes all selected speed effects and given the original frame rate of clips (I haven't found a way to get that automatically from movie sequences) creates linear interpolation curve for speed effect.
It is is more useful than constant speed value as you can then go and edit curve not having to work out how it should look like to get original speed in your final edit (it also creates meta strip that actually is trimmed correctly so it appears in correct size in VSE, but that part is omitted as it is outside the scope of the question).

def execute(self, context):
    # filter out non speed effects
    selection = [ seq for seq in context.scene.sequence_editor.sequences if seq.select and seq.type == 'SPEED' ]

    # get render frame rate and calculate how to scale input movie fps
    fc = context.scene.frame_current
    fps = bpy.context.scene.render.fps
    fcurves = bpy.context.scene.animation_data.action.fcurves
    factor = fps / self.original_framerate

    # remove current fcurves for speed_factor if there are any
    # we create set for faster lookups (at least I'd home it would be faster than naïve approach
    paths_to_remove = set((s.path_from_id("speed_factor") for s in selection))
    for f in fcurves:
        if f.data_path in paths_to_remove:
            fcurves.remove(f)

    for s in selection:
        s.use_default_fade = False
        s.use_as_speed = False
        factor = fps / self.original_framerate
        final_duration = s.input_1.frame_duration*factor
        final_duration = s.input_1.frame_duration*factor

        # create curve for this speed effect and add two keyframes
        curve = fcurves.new( s.path_from_id("speed_factor") )
        start_key = curve.keyframe_points.insert( s.frame_start, 0 )
        start_key.interpolation = 'LINEAR'
        end_point = curve.keyframe_points.insert( s.frame_start + final_duration, s.input_1.frame_duration )
        end_point.interpolation = 'LINEAR'


Toggle X-Ray on top row of 3DView Editor.

Or check JachymMichal's answer here.


In Blender, the way you get rid of a window is to merge that window into another one. There is a trick to this, however; two windows to be merged have to have the exact same common dimension, so sometimes you need to split one window in two to be able to merge part of it with another. Looking at your illustration, you can merge the window you want to keep with the window immediately above it by clicking on the splitter widget in the upper right hand corner of the window you want to keep, and while holding the LMB down, moving the mouse so the cursor moves into the region of the window just above it. You should see an faint arrow appear in the upper window showing that that window is being removed. For the window just below the one you want to keep, which extends across the whole screen, use the splitter widget to divide this into three windows, one the exact width of the window you want to keep, the other two windows with the exact width of the windows above them. Using the same technique as above, merge the three windows above into the three windows below.

Clearing the other windows is just a matter of applying the same techniques: finding two windows with a common dimension and merging them together, and if there are not two windows with a common dimension, splitting a window and sizing the resultant bits so that one of them has a common dimension with another adjacent to it.

There is another way: save your file, quite Blender, and start a new Blender instance. Navigate to the "file > open", and in the file browser, find the file you saved. Then, in the extreme lower pane of the file browser window, find the "Open Blender file" pane, and if the box labeled "load UI" is checked, uncheck it. This will load the contents, without loading the window layout.


It comes from the UV, named so because XY is used for 3d localisation and UV is just a planar representation of the unwrap on a model. So work your UV correctly through the UV editor, in this case you should just select all the faces for the screen and press U then 'unwrap' or 'unwrap from view' if your are in front of the object in a precise way as when selecting the view with numpad numbers. Also when you are done with that you can select the other faces and assign a different material to it.


Yes, that answer is valid.

You only need one of these 2 lines, they're just a different way to access the Screen data block. A screen datablock defines the layout of editors (which is why there is a selection of "screens" for e.g. UV editing, animation, etc. and you can fully customized that).

Every window (the system window blender runs in) has a screen property. Every screen in turn has a scene property which defines the active editable scene. Both of these properties are selectable at the top of the window by default. The most convenient way to set the screen.scene property is probably via the context:

bpy.context.screen.scene = some_scene


Is there a way to overlay two similar UV islands with identical vertex count?

Automatically unwrapping  identical geometry pieces one by one should produce identical UV layouts.
I.e. if you have a row of identical parts of geometry, select one, do unwrap, select another, etc. Selecting all at once may produce alike, but different islands.

If geometry is not identical, I'm afraid you're stuck with manually scaling down to zero required vertexes.


How can i create a 3d curve/saddle shape?

Bezier curves are not the proper tool for this, curves are useful mainly for extrusion based geometries, or sections-swept-along-paths shapes.

NURBS surfaces may be closer to what you need, though they will require some considerable manual modeling work, and they are a half-baked tool in Blender that wont help much.

You may also model this manually using meshes and subdivisions, but again will require a lot of manual modelling and not necessarily yield a mathematically accurate surface.

The best way to model such thing is using the builtin addon Add Mesh: Extra Objects Python script

Start by opening File > User Preferences > Addons then search for Extra and activate the Add Mesh: Extra Objects addon.

Then in the 3D View press Shift+A > Add > Mesh > Math Function > Z Math Function

According to Wikipedia the mathematical function for a simple Saddle Point surface is Z = X^2 - Y^2 so in the operator properties change the input formula to the desired function using Python notation which should be (x**2 - Y**2)


What setting locks local rotation and scaling of an object?

It sounds like you have activated the Manipulate Pivot Points tool.  It's found directly to the right of the Pivot Point selection menu in 3D view > Header.

Here's a demo.

It can also be toggled with ⎇ Alt, (comma).

Now, if you mistakenly press some keyboard shortcut that ends up causing you grief like this; you can try pulling down the top header bar to view the Info area.  It should contain most of what you've recently done.(to view EVERYTHING you'd have to enable debug logging, that's gets messy quickly)


How do I crop everything in Video Editor?

You can group your clips in to a meta strip by selecting them and hitting Ctrl G. If you want to edit the clips inside it after grouping them, select your meta strip and hit Tab.

You can now apply an Image Crop to the meta strip in the properties panel (N). Be sure to check Image Offset. You will also need to change the render dimensions to the correct size.

Screenshot:

You can avoid the need to crop in the video sequence editor entirely by performing the crop in the render dimensions. Simply set the dimensions to the target aspect ratio for you image.


Apply transform (rotation) to video clip before motion tracking

Though I don't think is necessary to rotate your image, here's how to do it:

Add two trackers on opposite ends of the frame that don't track anything in the footage, with a a weight of 0 (so they don't add anything to the camera solver) and use those to control the rotation.

On the Display tab enable Display Stabilization.

Enable 2D stabilization. Select both trackers and add them to the stabilization box.

Do not enable autoscale, enable Stabilize Rotation and select one of the trackers to control the rotation of the image.

You can rotate the image now by moving any of the trackers up or down.


How do I do GPU rendering with enabled OptiX from the Command Line?

Thank you to everyone who helped!
I found a solution to the problem:
-b $filename -noaudio -E 'CYCLES' -s 20 -e 170 -a -F 'PNG' -- --cycles-device OPTIX

Explanation:
-s 20 -e 170

Set the -s start frame to 20 and the -e end frame to 170.
-a

Render the whole animation using all the settings saved in the blend-file.
-- --cycles-device OPTIX

Override the device that is used to render frames.


Use the shrinkwrap-modifier in combination with a subsurf- or multires-modifier.
Make sure that the shrinkwrap is stacked lower than the subsurf- or multires-modifier to gain detail.

When using the multires-modifier, you can apply the shrinkwrap-modifier and the gained detail will be 'absorbed' by the multires. You can then enter sculpt mode to add and or smooth the desired detail while keeping your relatively low poly retopologized mesh.


What are anticipated use cases for Is Diffuse Ray (Light Path Node) in Eevee?

While with regular viewport rendering alone it is hard to find a use case, while using probes it can have a visible effect.
If you use an Irradiance Volume probe and bake baking indirect lighting, you use it to change object color for direct visibility, while indirect light sees it differently.
In the example below the sphere color is is red, but through the Is Diffuse output we tell the rays bouncing off the surface it is blue, as such you can see a faint bluish tint to the color bleed effect on the wall.


User input to change materials properties

Annotate your operator.
Add properties to the operator containing the defaults to set, which can in themselves be set.
Have added the only the metallic property, and a draw method,

add more to suit.
import bpy
from bpy.props import FloatProperty

class ResetAllMaterialsOperator(bpy.types.Operator):
    """Affects all Materials in the scene"""
    bl_idname = "material.reset_all_materials_operator"
    bl_label = "Reset all Materials"
    bl_options = {'REGISTER', 'UNDO'}

    metallic = FloatProperty(
            name="Metallic",
            default=0.75,
            )

    def draw(self, context):
        self.layout.prop(self, "metallic")

    def execute(self, context):
        for mat in bpy.data.materials:
            if mat.use_nodes:
                for n in mat.node_tree.nodes:
                    if n.type == "BSDF_PRINCIPLED" and n.label == "":

                        n.inputs[4].default_value = self.metallic
                        n.inputs[5].default_value = 0.1
                        n.inputs[7].default_value = 0.5

                        for l in mat.node_tree.links:
                            if l.from_node.type == "TEX_IMAGE" and l.to_node.type == "BSDF_PRINCIPLED":
                                if l.to_socket.identifier == "Alpha":
                                    mat.node_tree.links.remove(l)
                        break

        return {'FINISHED'}

class TestPanel(bpy.types.Panel):
    bl_space_type = 'VIEW_3D'
    bl_region_type = 'UI'
    bl_idname = "TEST_PT_test"
    bl_category = "TEST 2"
    bl_label = "Test label"

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

        box = layout.box()
        row = box.column()
        row.operator("material.reset_all_materials_operator")

classes = (TestPanel,  ResetAllMaterialsOperator)

def register():
    for cls in classes:
        bpy.utils.register_class(cls)

def unregister():
    for cls in reversed(classes):
        bpy.utils.unregister_class(cls)

if __name__ == "__main__":
    register()


How to make the transparency of my objects back to normal?

It looks like you have enabled the viewport X-Ray shading option.

You probably enabled it with the shortcut ⎇ AltZ.


scroll up on the properties window (see that bar on the far right?


How to particle system with permanent particles

Set the Frame start and End frame to 1, and the lifetime to the length of frames for the whole the animation.


You've directly plugged the Image Texture into the Output, in that case it acts like an Emission shader, what you need to do is plug a Diffuse shader between the Image Texture and the Output:


Why doesn't my SkyTexture show up in the preview tab?

In your world settings, do you have real sky, and environment lighting enabled? Here are the steps to get your desired results.
Go to the world tab and click real sky, then environment lighting. Then, make sure that you have sky texture selected in the drop down menu off to the right.
Next, go to the textures tab and choose your image. Set the mapping as you already have, and click horizon, and that should do it. The world settings I use are as in the attached screenshot.
Hope that helps.


(Left)

If you have a bottom face which is a large Ngon with a concave edge, Catmull-Clark subdivision will cut the corner,even if the face has holding loops on its perimeter.

(Right)

You need to give the subdivision convex faces to work with, preferably quads. I seem to remember Andrew's Anvil does it like this.


I'm having a problem with the visiblility of an object just in cycles

Finally I found the problem, the visibility was turned off for the camera.


How can I get Blender to just do Matcap shading for the selected object?

I am afraid you can do it now only in blender internal in GLSL shading. But that shouldn't matter if you want it for sculpting. You only need some matcap textures. Here is what to set:

Good thing is you can setup as many matcaps as you want for your objects:)


How to set default save location for an image?

Were you able to figure this one out? I'm sorry if I'm misunderstanding, or if this might have to do with some kind of computer file storage settings or compatibility error. You may have tried this already; But after doing the usual render action:
Render Image (f12)> Save As
In the file explorer I click the "Create New Directory" folder icon and then from then on it always renders to that folder, for the project you're working on. If you have multiple projects that you would like to keep saving to the same folder, it should usually keep it the same.


Particle system hair lines are facing downwards. How to make them facing upwards?

It seems like a Normal problem. Particles have a reference direction based on the poly surface. Try to flip your normals as you rather a hairy doughnut than a bearded one. This is a good article: https://www.katsbits.com/codex/flip-normals/


Solution is to disable Snap during transformation: Shift+Tab


How do I stop hair particles going through the body and the head?

Collision with the emitter is not supported yet (2.77).

But there is a workaround for this problem. So you want to collide the hair with the emitter but there is no self collision? Well but collision with other objects works, right? Right! So you simply have to duplicate the entire emitter mesh and set it to a "fake self collider!

How it is done:

Step 1: Duplicate the emitter mesh (select the Mesh and hit shift+D. Right Click to place the mesh at the
same position as the original mesh).
Step 2: Go to the Object Menu and deselect all Ray Visibilities. This way the duplication will not get rendered.
Step 2.5 (Optional): Now we want to eliminate the visibility of the duplication in the viewport. But simply restricting the view port visibility (by clicking the eye in the outliner) is not possible, because this way the collision may not be triggered.
Change the display mode from "textured" to "bounds" in the Object Display Settings. This way your duplicated mesh will only get displayed as a box and will not generate any annoying clipping artifacts.

Step 3: Enable collision on the duplicated object.

Step 4: Make sure everything is set up properly! In the modifier panel, the original emitter mesh should have the Armature at first position, followed by the Particles/Hair and followed by Subsurf.

Step 5: Also make sure the duplicated mesh has no Particle/Hair modifier. If it has one, you have to delete it in the particle panel!

Now your hair should collide correctly with the emitter!

If the hair still bugs into the body, try the following:
-in the hair dynamics setting, raise the "Quality" Amount (for me normally 5 Steps works just fine).
-in the collision settings of the collider, raise the "Outer face thickness" in the "Soft Body and Cloth" Settings.
-Raise the number of Subdivisions of the collider mesh (As i know, the collision does not get calculated by the faces of the collider but instead by the edges. If your mesh is to low poly the hair will slip through it)
-Raise the number of hair "segments" in the hair emitter settings.


How can I remove darkness from behind objects?

Your image alpha channel must be used for the mix factor between the transparent area and the color information (diffuse). So, just connect the Alpha output of the image node to the factor input of your Mix Shader node. This makes it so that only the parts of the image that are transparent are actually appear as transparent.

Just a proposal. Unfortunately we don't know you node tree for your tree planes.


How to export blender file with armature to glb

Start by trying the latest stable version, Blender 2.81a.  If that fails, make a backup of your project and try downloading an "Experimental" build of 2.82 from: https://builder.blender.org/download/

The reason I suggest this is that many armature-related bugs and issues have been corrected over the last 6 months or so in the glTF exporter, and not all of those fixes have yet made it out into a stable release of Blender as of this writing.  Several new fixes will be released with 2.82.

One other option to consider, if this really is a mechanical robotic arm that does not move in a cartoonish or organic way:  You could get rid of the bones and armature, and just have each mechanical section of the arm be its own object, parented to the one above.  Then you can use traditional node-based animations, instead of bones and armatures that are meant for more organic movements.  The robotic arm could have a specific shoulder joint with a specific elbow joint as its child, and the object movements would be animated object position/rotations that should export correctly to glTF.


Glass material is smudgy and doesn't look like glass

Some things that could help:

To brighten shadows inside the glass, add more Transmission bounces
For shooting glass (and other shiny objects), use high-contrast lighting
Denoiser still needs a lot of samples to avoid artifacts and smudges

3-4 lights, HDRI environment, 1000 Render Samples + Denoiser

Related:
How to make this glass more realistic?
How to illuminate the darkness inside glass objects in Cycles?


I tried to baked my high poly sculpt onto my low poly retopo, but it didn't work? what happened?

in bake/ selected to active/ play with extrusion and Max ray distance. you can turn render sampling down to do fast test


Hooking a series of empties along a curve

There is a workaround to emulate dupliframe.

Add a curve.

Add a plane. In edit mode scale it way down.

Add an "Array" modifier to the plane, set the length to 'fit curve' and select the curve. Deselect "Relative offset" and select "Constant offset", set the value to the spacing you want between each empty.

Add a curve modifier and set it to the curve.

Create an empty object. In object mode, select it then select the arrayed plane (not the curve). Go to Object > Parent (or press  CTRL  + P) and select "Object".

Select the arrayed plane and go to object info > Instancing and select "Faces". Uncheck "Render instancer" so that the plane doesn't get rendered. (Useless in your case since you are only interested in exporting it)

Now when you export your file, for example in fbx, it will contain the individual empties. Just delete the "plane" object to get rid of it. No need to apply the modifiers.

If you want for example your empties to be 2 meters above the curve, just move the original empty 2 meters along the z axis in object mode.


What is the purpose of the "Color Space" on image texture nodes?

Depending on your color management setting in the Scene Properties Editor, Blender will interpret the colors in an image in different ways, (i.e. apply a gamma curve to it, or adjust the color gamut/saturation of the image^)

Changing the color space to noncolor basically tells Blender to skip that conversion, i.e. a bump map is should not be color-managed.

^ I am greatly simplifying what 'color management' is, but for the purpose of this, I think it's sufficient.


2.8 now has font selection for the VSE and the change was backported to 2.7 branch as well.


How to fade an object evenly into transparency to give it distance look in blender 2.82

If it's a still image you could  make the material fade to transparent from the front to the back of the object using the material itself (I realize this would not work if the objects are animated and distance to camera is controlling transparency). Not sure what your use case is.


Watch Frames of Animation Already Rendered While Still Rendering

Thanks for the helpful comments.

For anyone that finds this in the future with the same question, if you just cancel the render with escape it will save the avi up to frame you were up to, so you can just note down what frame that was and start rendering again from after that and then combine the avi.


Delete any "custom NORMALS" / VERTEX GROUPS on your object properties. Delete any other irrelevant information (this is caused by a smooth group from other software).

Also check you don´t have UNchecked the EYE icon and the EDIT icon on one of your modifiers. This is the reason why you see something in Edit mode and then another on Object mode.

Last but not least, like it´s been mentioned, you have to CTRL+A your rug to apply transformations.

Thank you if you vote my answer.

BFCT_Schiller.