Blender can handle a million vertices in one object better than it can handle 10,000 objects in one scene. This means you should get better performance if you create all the vertices in one object instead of many individual objects.

Using blender 2.7x -

import bpy
import bmesh
import mathutils

# create the materials used
# simple BI materials used
MatAu = bpy.data.materials.new('Mat.Au')
MatAu.diffuse_color = Color((0.8,0.7,0.2))
MatC  = bpy.data.materials.new('Mat.C')
MatC.diffuse_color = Color((0.1,0.1,0.1))
MatH  = bpy.data.materials.new('Mat.H')
MatH.diffuse_color = Color((0.8,0.7,0.2))

# create an empty mesh object and add it to the scene
sphereMesh = bpy.data.meshes.new('AllSpheres')
sphereObj  = bpy.data.objects.new('AllSpheres', sphereMesh)
bpy.context.scene.objects.link(sphereObj)
bpy.context.scene.objects.active = sphereObj

# create slots for each material then add each material to the object
while len(sphereObj.material_slots) < 3:
    bpy.ops.object.material_slot_add()
sphereObj.material_slots[0].material = MatAu
sphereObj.material_slots[1].material = MatC
sphereObj.material_slots[2].material = MatH

# test data to be swapped for data in file
# type, location, scale
data = [('C', (1.0, 1.0, 1.0), 0.2),
        ('H', (2.0, 2.0, 2.0), 0.4),
        ('Au',(3.0, 3.0, 3.0), 0.8),
        ('C', (4.0, 4.0, 4.0), 1.2),
        ('H', (5.0, 5.0, 5.0), 0.2),
        ('Au',(6.0, 6.0, 6.0), 0.8),
        ('C', (7.0, 7.0, 7.0), 0.4),
        ('H', (8.0, 8.0, 8.0), 0.8),
        ('Au',(9.0, 9.0, 9.0), 1.2),
]

bm = bmesh.new()
for i in data:
    locMatrix = mathutils.Matrix.Translation(i[1])
    scaleMatrix = mathutils.Matrix.Scale(i[2], 4)
    mesh = bmesh.ops.create_uvsphere(bm, u_segments=8, v_segments=8,
                    diameter=1.0, matrix=locMatrix*scaleMatrix)
    for v in mesh['verts']:
        for f in v.link_faces:
            if i[0] == 'Au':
                f.material_index = 0 # material_index matches material_slots[x]
            elif i[0] == 'C':
                f.material_index = 1
            elif i[0] == 'H':
                f.material_index = 2

bm.to_mesh(sphereMesh)
bm.free()

For 2.80+ some small changes are needed

import bpy
import bmesh
import mathutils

# create the materials used
# simple BI materials used
MatAu = bpy.data.materials.new('Mat.Au')
MatAu.diffuse_color = (0.8,0.7,0.2,1.0)
MatC  = bpy.data.materials.new('Mat.C')
MatC.diffuse_color = (0.1,0.1,0.1,1.0)
MatH  = bpy.data.materials.new('Mat.H')
MatH.diffuse_color = (0.8,0.7,0.2,1.0)

# create an empty mesh object and add it to the scene
sphereMesh = bpy.data.meshes.new('AllSpheres')
sphereObj  = bpy.data.objects.new('AllSpheres', sphereMesh)
bpy.context.collection.objects.link(sphereObj)
bpy.context.view_layer.objects.active = sphereObj

# create slots for each material then add each material to the object
while len(sphereObj.material_slots) < 3:
    bpy.ops.object.material_slot_add()
sphereObj.material_slots[0].material = MatAu
sphereObj.material_slots[1].material = MatC
sphereObj.material_slots[2].material = MatH

# test data to be swapped for data in file
# type, location, scale
data = [('C', (1.0, 1.0, 1.0), 0.2),
        ('H', (2.0, 2.0, 2.0), 0.4),
        ('Au',(3.0, 3.0, 3.0), 0.8),
        ('C', (4.0, 4.0, 4.0), 1.2),
        ('H', (5.0, 5.0, 5.0), 0.2),
        ('Au',(6.0, 6.0, 6.0), 0.8),
        ('C', (7.0, 7.0, 7.0), 0.4),
        ('H', (8.0, 8.0, 8.0), 0.8),
        ('Au',(9.0, 9.0, 9.0), 1.2),
]

bm = bmesh.new()
for i in data:
    locMatrix = mathutils.Matrix.Translation(i[1])
    scaleMatrix = mathutils.Matrix.Scale(i[2], 4)
    mesh = bmesh.ops.create_uvsphere(bm, u_segments=8, v_segments=8,
                    diameter=1.0, matrix=locMatrix @ scaleMatrix)
    for v in mesh['verts']:
        for f in v.link_faces:
            if i[0] == 'Au':
                f.material_index = 0 # material_index matches material_slots[x]
            elif i[0] == 'C':
                f.material_index = 1
            elif i[0] == 'H':
                f.material_index = 2

bm.to_mesh(sphereMesh)
bm.free()


Maybe try changing the world lighting so that the shadows aren't so dark. Softer lighting seems to be a solution to this problem.


What compute device does the material preview use to render?

By using GPU-Z to see gpu load its easy to see that material preview does not use gpu (0% usage). Usage of CPU on the other hand rises when preview updates.

The problem is also how the material preview is coded.

it refreshes with re-scale instead of just computing more samples or only downsizing the preview.
it refreshes not smartly but on every "change". When some value is clicked but not changed, when new node is added but not connected. When you draw line from output and then cancel etc. this could go on and on.

Lot of things blender already has could use more attention from devs..


How to copy mesh to new files with Python?

Found how to do it. The code I had was half the solution.

After creating a new file, executing the following script adds the mesh to a collection in the scene as I needed. It assumes there's no collection and only one data block in the blend file.

add_object.py

import bpy

collection = bpy.data.collections.new("Collection 1")
bpy.context.scene.collection.children.link(collection)
collection.objects.link(bpy.data.objects[0])
bpy.ops.wm.save_as_mainfile(filepath=bpy.data.filepath)

To execute the script, I executed this in a loop:

blender.exe  <path_to_new_blend_file> --background --python add_object.py


First off, its hard to tell from the picture but the last edge loop looks very thick, possibly indicating there is a double edge there? maybe check that but otherwise, i made a cylinder with the same amount of edges, the extra extruded edges and triangles. The grid fill seems to work fine if you have the right settings and right active edge.

Or am I missing somthing? is this not the desired effect?


You have probably unwrapped the UV before you made the margin wider. Mesh changes require UV changes accordingly to avoid distortion. Best to avoid unwrapping unless no further changes to the mesh are planned.

Unwrapped the geometry:

Changed the mesh. The UVs are no more correct:

Corrected UVs:


Can't find in my viewport but it shows in the outliner

Trying pressing the Tilde key (~) to show all layers and then pressing Alt + H to unhide all objects. It looks like there are objects in other layers which could be where the missing object is.


How can I rename selected objects instead of just the active object?

You can do something like this:
import bpy

for ob in bpy.data.objects:
    if ob.select_get():
        #ob.name=ob.material_slots[0].name #this can fail if no material is assigned
        print(ob.name)

Or using context as @batFINGER suggests
import bpy

for ob in bpy.context.selected_objects:
     #ob.name=ob.material_slots[0].name #this can fail if no material is assigned
     print(ob.name)


What is simplest way to join particles into a single mesh and modify during animation?

A single mesh can be created from a particle system by using modifiers.

Create a particle system. For this example, also create a container to keep the particles in a volume.
Add a cube which fully encloses the particle system and its container. After some simulation, the geometry will look like this:

Add a sphere which will be used to display the particle system. Any manifold object can be used. If non-manifold objects are used, this solution will not work.
Add a modifier to make this sphere a particle system instance. At this point, each sphere is a separate mesh. Therefore, filtering modifiers operate on each sphere, not the combined mesh.

Add a modifier to perform an intersection with the particle system and the largest cube. This will create a single mesh from all of the spheres.
Add a Laplacian Smooth modifier. The mesh will be smoothed eliminating the appearance of intersecting spheres.

Now other operations like Booleans can be applied.


I found a solution on my own. Turns out that there's a "display scaling" option now that wasn't there in earlier versions of Blender.


You can make a theme from the Themes tab of the User Preferences (from the File menu).

From the "Presets" drop-down, pick a base theme, and then just start tweaking! You can see the results immediately, and when you're done, you can hit the plus button next to the Presets box to save your theme.

On Mac, you can find your saved themes in ~/Library/Application Support/Blender/<version>/scripts/presets/interface_theme (hit Shift+Ctrl+G, paste it in, and put in the correct version).

(On Linux, it's probably somewhere in ~/.config, and I've got no clue where it is on Windows. If someone does know, please edit my answer!)

The theme in your picture actually looks like the Graph theme, which should be installed by default. You should be able to just select it. (But be sure to hit Save User Settings at the bottom! Otherwise you'll lose your changes when you quit.)

Edit: Fonts are not part of the theme at all. You can change your font in the System tab, by entering a path to a font file in the Interface Font box in the bottom right (of course you can just use the open panel button).


To do something to part of a render based on an ID mask, you need to first separate that part out. One way to do this is:

Use the ID mask node to get a boolean mask of the part you want from the ID pass. When given the same index as the one you set in your material (in this case 3), this node will give you mask where pixels on that material are 1, and everything else is 0.
Use this mask to set the alpha channel of your image, with a Set Alpha node.
Perform whatever operation you want (blur).
Composite the result back over your first image, with an Alpha Over node.

That said,

If you are trying to create a bloom effect you may be better off separating by brightness alone. This works best if you make your scene with a realistic dynamic range (tl;dr: make lights bright and adjust the camera exposure).

If you have your lights set up with appropriate brightness, you can get pretty nice results with just the Glare node:

Regarding this comment:

  Why can't we blur a material without Pass index? I mean, it's already a seperated and unique object. Why blur isn't just a material's property? Why I can't see the actual render in Render mode view? Thank you in advance, you've already helped me so much.

The compositor does post processing, that is, manipulations to the image after the render engine has rendered it. The compositor doesn't deal with 3D objects anymore, but rather flat arrays of pixels the render engine has spit out. So, if we want to do something to a very specific set of pixels, we need to have the render engine spit out a flat array of pixels telling us which pixels represent our material (a mask). Then we can have the compositor use that information to change some pixels to our liking.

Blur isn't a material property because materials describe how light interacts with a surface. A surface can't really be "blurry" in the sense you're looking for. In the case of bloom, in the real world the object's surface isn't blurred, rather, our view of it is what is blurred.   So, blurring our "view" of the scene — the render engine's output — seems a reasonable way of implementing a similar effect.
It should be noted that "blur" is perhaps too simple a term to describe what is actually going on with what we call "glare" and "lens flare"; the phenomena involved can get quite complex.


Under what conditions does "select non-manifold not show up in the select menu?

You must be in vertex-edit mode in order to have that option.

Edit: orrrr edge-edit mode, confirmed.


How do I import XYZ AND a fourth parameter that adds color to my objects?

Create a material that applies your color ramp depending on the vertex color. That way we dont need to create a separate material for each sphere and can easily manipulate the color ramp in one material and all spheres will change accordingly.

Create the spheres and set the color of all there vertices to your Q-Value

import bpy
import random

mat = bpy.data.materials['Material'] # The name of the Material you created
# create sphere
bpy.ops.mesh.primitive_uv_sphere_add(segments=32, ring_count=16, radius=1, calc_uvs=True, enter_editmode=False, align='WORLD', location=(0, 0, 0), rotation=(0, 0, 0))

obj = bpy.context.active_object
# apply material
obj.data.materials.append(mat)

mesh = obj.data

# create vertex color map
mesh.vertex_colors.new()

color_layer = mesh.vertex_colors["Col"]

# color all vertecys
q = random.random() # your Value here
color = [q,q,q,1]
i = 0
for poly in mesh.polygons:
    for idx in poly.loop_indices:
        rgb = color
        color_layer.data[i].color = rgb
        i += 1

Set your viewport mode to shaded, to actually see the color that's applied by the shader.

If you want to be realy fancy you could export your data as an OBJ file (they are very similar to CSV) with vertex colors. That way you wouldn't even depend on Blender.

GIF of whole process

Run script

Create Shader


Is there a way to have one material for cycles and the BI

Without material nodes
You can sort of do this by enabling and disabling material nodes. (note that you cannot use material nodes in your BI material with this approach)
For example:

Create a BI material:

Switch to cycles and enable material nodes:

Create a cycles material:

Switch to BI and disable nodes:

Your original BI material will appear unchanged.
With material nodes:
If you do need material nodes for your BI material, then you will have to create both the cycles material nodes and the BI material nodes in the same node tree:

Note that you can only add nodes for the render engine that is selected (though I think you can add any node regardless if you add them from python), so you will have to switch the selected render engine back and forth.


Python's uuid module cause c runtime error in ms-windows

This is a very unfortunate glitch, at the moment has no nice solution. Both Blender and Python devs are aware of it.

The problem is with importing uuid (which requests happens to use).

For now, you can workaround this by temporarily disabling ctypes with the uuid module.

See:

http://bugs.python.org/issue17213
http://developer.blender.org/T38364
http://developer.blender.org/T27666

from: addons/io_online_sketchfab/__init__.py

# uuid module causes an error messagebox on windows.
#
# using a dirty workaround to preload uuid without ctypes,
# until blender gets compiled with vs2013
def uuid_workaround():
    import platform
    if platform.system() == "Windows":
        import ctypes
        CDLL = ctypes.CDLL
        ctypes.CDLL = None
        import uuid
        ctypes.CDLL = CDLL

uuid_workaround()

# now import a module which uses 'uuid'
import requests

We'll likely be updating to vc2013 for Blender 2.71, I'm not sure if this resolves the issue though, this needs some further investigation from an ms-windows developer.


Rigging fabrication time for serious production and referencing

How much times is needed to build a rig like Victor from Cosmo Laundromat?

About a week or two of one_man_hours for such a rig. Depends on how good that artist is and how much he has automated with scripts.

  Does it need a big knowledge in Blender python API ?

Yes, every technical artist building rigs needs to know the API of the software, Blender or not Blender. A lot of functionality that you take as granted from Maya is not present in Blender and has to be scripted. Scripts also speed the workflow, so in production environment they are a must. The API is well documented here: https://www.blender.org/api/blender_python_api_current/

It takes about 2 months of full work time for a new technical person to become proficient in production blender rigging without prior knowledge of python, 1 month with python knowledge and slight prior experience with rigging and couple of weeks for a technical artist that transits between applications.

  Is it possible to found ressources for build it (dvd, artists)?

All resources for Blender are here: Resources for Blender

I would cheery pick as most useful the Blender Cloud (for Victor rig), Blender Cookie (good rigging tutorials), and Rigify addon (for reverse-engineering).

Also is good to know that Blender community is mainly composed of hobbyist, that don't have that much experience, and everyone is making tutorials these days. So with Blender there is a lot of free tutorials that will show you the wrong way to do things.

An example how not to do rigging is here: http://blog.digitaltutors.com/how-to-create-your-first-character-rig-in-blender-part-1/

Also Blender develops constantly - so many tutorials are now out-of-date.

  Is it possible like Maya to reference the model with his rig and skin into an other scene to be animated and still keeping the link between the two scene if an update is made on the rig?

Yes, this is possible but has limitations. When you link a character, you need to create a proxy of the rig, that can be edited.

When you make changes to the rig in the linked file, you have to re-create the proxy rig, and re-link it's animations. It won't happen automatically. Also the edit of the rig can easily break the animations, as everything in Blender is referenced only by names - so careful with renaming.

Also this limits the number of linked instances you can use in a scene to 1.


Cycles shadows different in live render and final render

This probably not a bug, but differences in settings between viewport/preview and the final render.

Checklist:

Check that all objects that appear in the preview also appear in the final render, especially lamps. See: https://blender.stackexchange.com/a/1114/245

Check that the sampling settings are the same for preview and final render. See https://blender.stackexchange.com/a/111591/245 for reference.
For completeness but probably not relevant: Check the modifiers for any difference between preview and final render.

Given your description there seems to be a problem in the rendering section so you might also use this answer for tracking down your problem.

I specifically think that the amount of bounces is lower in the preview then in the final render. The increased diffuse lighting makes the shadow lighter.

EDIT:

The problem seems to be in the node setup:

The problem is, that the shadow has a strange mix between alpha and color:

The diameter of the shadow changes with the threshhold on the alpha channel!

Maybe you could try to use a shadowcatcher material/setup as described here.

Investigating further, I think that you set up everything the right way, but this might be indeed a shortcoming of blender as discussed in the developemnt group here.


how to edit the custom shape of te bones in blenrig

You can find the mesh objects that BlenRig uses for custom bone shapes on layer 20.


How to add playing videos to the 3d viewport?

Create a plane, give it a material.
In the Shader Editor create this node chain: Texture Coordinate (Generated output socket) > Image Texture > Diffuse or Emission > Material Output. You may also want to put a Mapping node between the Texture Coordinate and the Image Texture in order to move the movie in the plane.
In the Image Texture load your video, tweak some of its settings: enable Auto-Refresh and set the amount of frames your movie requires.

Or, as No-Can-Do says, enable the Import Images As Planes addon and press ShiftA > Images > Images As Planes
and open the Shader Editor to tweak the settings.
If your video is not a video file, but a series of numbered images. Press the gear icon when adding an image as plane, and select Animate Image Sequences,so that all the images are imported in a single plane and not as multiple planes, each one with a single frame.


How do I Texture paint with Realistic Textures?

If you don't want to paint with a solid colour in texture painting you can choose a texture to use as a brush to paint onto your object.

The first step is to define the texture, while any built-in textures can be used an image would be the most common source. In the texture panel create a new brush texture and select the image (this will look a little different if your using Blender Internal)

In the Tools sidebar T you will find a panel for Texture, choose the texture you have setup and select stencil for the mapping type. You will also see options to alter the rotation and scale for the texture. You can also create a new brush texture by clicking the + under the texture preview.

When you move the cursor over the 3dview you will now see the texture in a transparent overlay. You can use  RMB to drag the image into place, ⎈ Ctrl RMB to rotate and ⇧ Shift RMB to scale, when you  LMB on the texture it will paint it onto the image in the selected material slot. This allows you to easily place the brush texture to match up with existing texture on your model.


Don't keyframe Animation Nodes properties, instead, use an Animate Node:


Eevee: Light sources appear as bright orbs in reflections

I solved the issue and am happy with the results, even if this is technically working around it. The core problem was that I was using a huge light radius: You want the sphere of the point light to encompass and represent only the bulb. I set it to 0.01 instead of the default 0.25: This not only results in the correct shadow softness, but the white orb is now just a tiny speck, precisely how a bright bulb should appear in a reflection! It's also hidden behind a lamp cover so it shines even this way only when seen from the right angle.


How to create old looking/ cracked glass

Here, try this:

As Eric pointed out in the comments, the secret here is a Voronai texture set to "distance to edge". I used ColorRamps to remove all the grayscale and leave only black outlines. I made a large, medium, and small set of cracks and mixed them together. I then used this combo as a main image (BaseColor), as a basis for a normal map, and I also inverted it to make an alpha mask.

Final result looks like this:

This can obviously be made better by creating more distortion among the cracks, but I feel this is a good place to start. I'll upload the .blend file so you can experiment.
File is here -
Hope this helps.


'bpy_prop_collection' object has no attribute 'link'?

If you are interested: As of Blender 2.8x SceneObjects.link(object) is gone due to the new collection system. You can use CollectionObjects.link(my_object) instead so you just need to replace a single line to "update the script" for Blender 2.8x:

- bpy.context.scene.objects.link(object)
+ bpy.context.collection.objects.link(object)

Blender 2.80: Python API Changes

blender labyrinth generator 2.8x:

from random import shuffle
from array import *
import bpy

N=1
S=2
E=4
W=8

odir = {}
odir[N] = S
odir[S] = N
odir[W] = E
odir[E] = W

WIDTH=40
HEIGHT=40

coords = []
faces = []

d = [[0 for col in range(WIDTH)] for row in range(HEIGHT)]

for i in range(0,WIDTH):
    for j in range(0, HEIGHT):
        d[i][j] = 0

def carve( x, y ):
    dirs = [N,S,W,E]
    shuffle(dirs)

    for i in dirs:
        print(i)
        nx = x
        if i == E:
            nx =  nx + 1
        if i == W:
            nx = nx - 1
        ny = y
        if i == S:
            ny = ny +1
        if i == N:
            ny = ny - 1
        if nx >= 0 and nx < WIDTH and ny >=0 and ny < HEIGHT and d[nx][ny] == 0:
                d[x][y] = d[x][y] | i
                d[nx][ny] = d[nx][ny]  | odir[i]
                carve(nx, ny)

carve(0,0)

idx=0
step = 0.1

for x in range(0,WIDTH):
    for y in range( 0, HEIGHT ):
        if ( d[x][y] & N ) == 0:
            coords.append((x * step , y * step, 0 ))
            coords.append(((x+1) * step, y * step, 0 ))
            coords.append(((x+1) * step, y * step, step ))
            coords.append((x * step, y * step, step ))
            faces.append(( idx, idx+1, idx+2, idx+3))
            idx+=4
        if ( d[x][y] & S ) == 0:
            coords.append((x * step , (y+1) * step, 0 ))
            coords.append(((x+1) * step, (y+1) * step, 0 ))
            coords.append(((x+1) * step, (y+1) * step, step ))
            coords.append((x * step, (y+1) * step, step ))
            faces.append(( idx, idx+1, idx+2, idx+3))
            idx+=4
        if ( d[x][y] & E ) == 0:
            coords.append(((x+1) * step, y * step, 0 ))
            coords.append(((x+1) * step, (y+1) * step, 0 ))
            coords.append(((x+1) * step, (y+1) * step, step ))
            coords.append(((x+1) * step, y * step, step ))
            faces.append(( idx, idx+1, idx+2, idx+3))
            idx+=4
        if ( d[x][y] & W ) == 0:
            coords.append((x * step, y * step, 0 ))
            coords.append((x * step, (y+1) * step, 0 ))
            coords.append((x * step, (y+1) * step, step ))
            coords.append((x * step, y * step, step ))
            faces.append(( idx, idx+1, idx+2, idx+3))
            idx+=4

mesh = bpy.data.meshes.new(name="MyMesh")

object = bpy.data.objects.new( 'MESH', mesh )
bpy.context.scene.objects.link( object )

mesh.from_pydata( coords, [], faces )
mesh.update( calc_edges=True )


Can't bake a proper normal map in Blender 2.9

When you create a new image in order to bake the normals, enable 32-Bit Float:

Also, use another material for the high-poly object, otherwise the normal map will cumulate with the real bumps.


Can't find where to change add primitive operator properties

Please see below. The properties you are looking for are under the drop-down menu in the bottom left corner of the viewport. In 2.79 the default shortcut was F6, but it does not work in 2.8.


How can I create a wire-wove grid material in cycles?

I'm not super happy with this one, but when it comes down to it you might have to fiddle around with just about any solution that's given to you.  It's kind of the nature of procedural generation, so here goes.
This is based on another answer I did over here:
Sine wave on the environment texture
You can read through that for the whole discussion on this.  Here we do a Y Wave Texture influencing an X Wave Texture, and then reverse it to get a 90 degree rotation.  Then we add those two together and use it for the Alpha channel.

For this primitive plane, the scales should always be around the same (but they don't have to be exactly the same) and the Mix Factor controls the height of the wave.  So it should always be very close to 1, but how close depends on the scale of the wave textures.  You'll have to mess with them to get it to look right depending on the size of the mesh it's applied to.


How do I make a hole and resize it later?

Constraint Axis Scale

If your holes shapes are made by subtraction of extruded profiles along a single axis, you may consider the option to simply scale the faces in the 2D space of the plane perpendicular to that axis.

This can be done by pressing Shift just after the Scale shortcut (S) and before picking the normal axis (Z in the shown example), or by using the operator panel options.

If you need to use a different orientation than Global (e.g., local, custom, etc.), you'll have to press the keyboard combination (S -> Shift+Z) twice.

The animation above has Edge Length checkbox enabled in order to make the diameter length visible during the transformation.


How to remove personal data from a blend file

As far as I know, there is no way to strip this information from a .blend file without editing the file itself as you have done and that has its own set of cons.

Option 1

Work at the root directory of your system. ie. C:/personal_folder/ or on a portable medium. You say you don't have any images or such attached so this shouldn't log anything private such as your username or any other personal paths provided you don't import anything and all you have is a model.

Option 2

Export to another format and reimport back into Blender. Exporting to a simple format such as .obj will only export mesh data (if all you have is a mesh) and same goes for importing it back. I did this with a file saved on my desktop and the only instance I could find with personal info was the location to the file. Use this with method 1 for optimal results.

As it addresses your other privacy concerns, being identified as to what OS you're on is fairly useless information and if you're sharing a file here, you might even be asked what os you are running so provided that no personal paths are included you should be fine.


Texture paint means to hand paint with color, brushes etc over a texture applied to a UV mapped surface.

So, you must have a UV map, and then assign the texture to the UV map. This gives you a lot of choice to wht part of the texture is assigned to which UV face. You could also decide (or get) to have the same texture over all the UV faces (eg: a cube with a logo on all faces). If you have this or similar situation, when uyou paint in the viewport over the faces, you paint over a texture that is also mapped to other faces, so, you paint goes everywhere...

see this

or a simple cube

Try to see your UV map in the UV/image editor, and check which UV face is mapped to which texture part, berfore painting. Practice with a simple cuve first, and try what happens by

just creating a new uvmap in the object data panel on the right, "plus" button
instead, pressing u over the object in edit mode, all faces selected, and choosing different options

eg: selecting smart UV projection

you get something that behaves probably more as you intend...


This kind of topology works but it needs a bit more edge loops for your sphere than what you currently have:


Extrude whole selection

Delete inner segments and bridge gap

Now bevel edge and delete excess afterwards.

Follow up with an n-gon or grid fill.


How can I model this twisted arrangement of cubes?

Particles or Manual Edit

Consider using a Particle System on a helix strip mesh created by Simple Deform Twist modifier.  Particles would be a group of objects which are cubes with random variation of shape.  Use Initial Orientation Normal with some small Random Value as depicted above.  No Array Modifier.

If you have just a few cubes you could
Press the [Convert] button to make duplicates real
and give each a rotation by hand.

The imperfect cubes are in a group and you can see a rotation of one in edit mode.

You may wish to state if you want to keep the varIations in cube shape and rotation.

The image above show 2 examples of orientation.

Full Coverage.  Placing a single particle on each face in the Helix Mesh.

[Emission Number] = (face count + 1). Goal 1 particle per face. Close to meeting goal. Result is 2 particles in same position on top. I have never investigated if this is declared a defect. (I have never investigated fully.) If you are going to [Convert make real] this problem may lessen, since you can delete. [Particles/Face=1].  A Hidden Portion of curve may be a bearable near solution.  You can see the two different colored particles on top.  When you increment and decrement Emission Number you can see this (interesting) situation.


I think you will run into problems with such complex paths/curves. Extrude might work but I think beveling wont work well.

For an embossed look I would use the image as a bump map/texture/heigh map:

Add a plane in blender, UV-unwrap it and add your image as a bump map. You should unsharpen your image for a smooth beveling effect.

You could even mix differently smoothed images together for a more distinct look.


How to make solid hair for girl (not strand by strand)

Typically this is one or a couple of meshes, so it is mainly matter of picking the proper path rather than choosing a specific tool.
A way to approach would be sculpting indeed, if you prefer modeling it then create a rough mesh which will follow roughly the shape of the head, then extrude few faces to make this spiky ends of the strands and apply a subdivision modifier.
There must be plenty of examples out there, try the combination of keywords "sculpting hair mesh" either on google or youtube.


My spotlights are making weird shape reflections on glass

I'd advise getting rid o additional duplicate lamps overlapping in one spot, if one is not enough to light your scene up increase its strength.

Having double lamps overlapping is redundant and will likely lead to issues, besides the obvious performance issues. Having multiple lamps realistically distributed across your scene is of course ok and encouraged.

Anyway, you are most likely using either Area or Point lights, not spots, these are never visible in reflections, as far as I know.

Try disabling the Lamp object visibility to Cycles Glossy component.

Alternatively use a node setup in your lamp with a Light Path node limiting it's visibility to glossy components.


Why does zooming out too far cause my object to vanish?

Likely your viewport clipping end distance is too short. Press N in object mode to bring up the tool menu and change it under "view".


How exactly does the Sigma parameter affect the Velvet shader?

It rather seems to define the response curve towards the view angle.

The velvet shader makes a material look brighter the smaller the angle between the view vector and the surface tangent vector is, it's bright if you look on a surface in the tangent direction and dark if you look at it from it's surface normal direction.

With sigma=0, you seem to have to look at a surface perfectly in tangential direction to receive light, while higher values spread it across a wider range of angles so that with sigma=1, the distribution goes all the way to a normal view angle and is relatively even.


Animating judo throws and working with two animations at the same time?

This doesn't seem normal. Make sure both your armature are set in Pose Position.

That way, you should be able to animate one armature while the other play it's own animation.

If it doesn't, maybe provide your .blend file so we can dig deeper and faster.


How to add local attributes of an operator to a `bpy.app.handle`?

This can be done by defining a function in the namespace where your variables are accessible:

    def invoke(self, context, event):
        self.param = {self: 'my dict'}

        print(bpy.app.handlers.frame_change_post)
        print(self.handle in bpy.app.handlers.frame_change_post) # Always False
        #bpy.app.handlers.frame_change_post.clear()

        # local function that can access this namespace
        def handle_local(scene):
            # pass any vars you want
            self.handle(self, scene, context)

        bpy.app.handlers.frame_change_post.append(handle_local)

        return {'RUNNING_MODAL'}

Note: the line print(self.handle in bpy.app.handlers.frame_change_post) is no longer correct, using a function defined each time makes this check more involved.


The parts of this model are not showing in game engine nor do they have shading

For the shading problem: the viewport is currently in shaded mode

If the textures still aren't showing, bear in mind that only image textures are supported.

For parts of the model not showing, it is likely that the normals are inverted or that you are using single planes. In computer graphics, most faces have only one side, and if you look from the other side they will be transparent. To fix this you can:
 - Flip the normal to face the correct way (edit mode -> select face -> ctrl+N)
 - Disable backface culling

Viewing the normals using one of the following options is reccomended:

As should be evident, the selected faces have their normals flipped and are thus not visible from where the camera is.


I'm trying to use the denoise function, but the nodes aren't showing up on the render layers

You need to go to "View Layer properties" > Passes.
Every pass is a new output


How to stop blender from generating duplicate vertices on export?

It is incorrect to assume the number of glTF verts will equal the number of Blender verts. Each glTF vert has a unique normal for example, while each Blender vert can have a different normal for each poly it is in. Your model uses flat shading and you can see each vertex has multiple normals.

To handle this there are "duplicate" glTF verts (that have the same position, but different normals). The same thing happens for all other "vertex per poly" data, like UVs.
"Duplicate" verts are inserted only when necessary, so turn off export of anything you don't need—normals, tangents, UVs, vertex colors, materials—to get a smaller glTF vert count.


Open user preferences directly into Add-ons tab

You'd want to use
bpy.context.preferences.active_section = 'ADDONS'


Another solution using vertex bevel.

Add an edge top and bottom (for now you can F a temporary face for your object, it will be deleted later)

Select the vertices that define the edges and press Ctrl + Shift +  B followed by P to change the profile.

Hide everything except the bevel you just created with H

Alt + Shift select and use Bridge Edge Loops to complete the shape on each side


restricting area of UV project to projector plane

Orientation, scale and position of the projector will influence the UV project modifier.

So, starting from your configuration (I changed nothing except limiting the rendering of the plane to wire), simply scale and grab the projector.

About a 'better way' to do it. I don't know if it is a better way, but you can get rid of the UV Project modifier defining a UV map for the sphere, because the UV of the sphere will be inherited by the tile during the Boolean modifier operation.


How to set vertex radius when using skin modifier?

@lemon Was kind enough to help me find this answer:

def make_increase_width(self):
    size = self.properties.skin_size
    obj = bpy.context.active_object
    for iteration in self._iterations:
        size += self.properties.width_increase
    for iteration in self._iterations:
        for vert_index in self._iterations[iteration]:
            obj.data.skin_vertices[''].data[vert_index].radius = (size, size)
        size -= self.properties.width_increase

This is outside of edit mode, very fast and exactly what I needed.


How can I Extrude Objects According to Their Colors?

There may be a good answer within Blender.  But if you just need to get the job done, you could open your SVG file in Inkscape.  Inkscape has the ability to select objects by the same colors, e.g. select one object with the desired color and choose "Edit --> Select Same --> Fill Color".  In this way you could create several SVG files, each containing only objects of the same color.  You can then import each SVG file separately and give each one a group, so that you can select and edit the group easily.

I did this with a circuit board SVG (a two-dimensional one) I found online with the following results:

The curves can indeed be extruded without converting to meshes, simply modify the "Extrude" value under "Modification" in the "Geometry" section of the curve data tab.  If you want to set all the extrude values at once, join the curves first.  This is a good reason for keeping them as curves for as long as possible, btw.


Strange UV Unwrapping behaviour with Seams

I'm going to assume that this beveled cube was made from a Cube mesh.
When you add a Cube mesh to your scene, it automatically creates a UV map for you. Beveling the cube without unwrapping it after does not change this map by much (although it does result in some weird mapping).
However, when you made a seam and unwrapped the mesh, the old UV map was trashed. Blender now tries to figure out how to unwrap the whole mesh to a 2D space with the seams provided. However, Blender cannot do this because the provided seams are not sufficient.
Now, imagine your mesh was made of paper. You want to cut the paper at the appropriate edges so you can "unwrap" the paper to make it completely flat without tearing it. If you only cut the edges you marked as a seam, you cannot do this.
This is what Blender is doing. Because it cannot completely flatten the mesh, it gets confused and makes a whole mess of overlapping faces.
When marking seams, use the strategy above to try and place seams at the correct spots.


Subdivision Surface modifier is not visible in rendered shading mode

You should put more than 0 in the View parameter of your modifier, typically 2. View is for the Object or Rendered mode of the 3D view, Render is for a definitive render when you click the Render button in the Render menu of the Properties (6 is a lot though).


Bridge edge loops - select at least two edge loops

Welcome to Blender Stack exchange!

You issue here is that you are working with two separate objects. Blender can't make new geometry that connects to both objects and still have the two be separate.

To understand this a bit better, let's work through what you've asked Blender to do, and what Blender is capable of doing.

In 2.80, a new "multi edit" feature was added that allows you to select two objects in object mode and edit the underlying meshes at the same time. The key here is that the objects are separate. Once you exit out of edit mode (from working on the two at the same time) they have to again be separate, and thus cannot be joined together in any way.

Now what your asking Blender to do when using the Bridge Edge Loops tool is to make some new faces between two edge loops. Blender is perfectly happy doing that in almost all cases. However, when we think about what I mentioned before we'll see where the issue comes from. When you ask Blender to connect the edge loops, it connects each new face to both loops. But at the same time, you're telling Blender that it has to be able to separate these new faces back into 2 separate objects when you leave edit mode. Blender runs stuck here, which is why you get the error (which could definitely be a bit clearer), because there's no way for it to separate these faces back into two objects. Either each face belongs completely to one object, or completely to he other.

To fix all this, you just need to make your two cylinders one object. Blender will still keep them as two cylinders, but will treat them as a single entity. To do this, use Ctrl + J to join the objects in object mode. Now you have a single object to work with and Blender will happily bridge the two loops.


When this happens to me, I can usually get it back to normal by selecting an object and hitting keypad-period to reset the view to that object.


How do I get the correct context for Python operators?

After looking through the api documentation, it does not appear that there is a direct way to know which contexts an operator will work in.
Therefore, one way to determine this is to call an operator's poll method in every context to see if the operator will work (brute forcing it). Using this approach, the bpy.ops.sequencer.duplicate will work in the 'SEQUENCE_EDITOR' context, and only the sequence editor.

The script below simply runs through all the areas and polls the operator (line 15).

import bpy

#all the area types except 'EMPTY' from blender.org/api/blender_python_api_current/bpy.types.Area.html#bpy.types.Area.type
types = {'VIEW_3D', 'TIMELINE', 'GRAPH_EDITOR', 'DOPESHEET_EDITOR', 'NLA_EDITOR', 'IMAGE_EDITOR', 'SEQUENCE_EDITOR', 'CLIP_EDITOR', 'TEXT_EDITOR', 'NODE_EDITOR', 'LOGIC_EDITOR', 'PROPERTIES', 'OUTLINER', 'USER_PREFERENCES', 'INFO', 'FILE_BROWSER', 'CONSOLE'}

#save the current area
area = bpy.context.area.type

#try each type
for type in types:
    #set the context
    bpy.context.area.type = type

    #print out context where operator works (change the ops below to check a different operator)
    if bpy.ops.sequencer.duplicate.poll():
        print(type)

#leave the context where it was
bpy.context.area.type = area


Curve modifier doesn't follow curve in the correct axis

Apply the rotation of your curve (CtrlA)
In Edit mode, right click and Switch Direction so that the normals go from bottom to top
You’ve keyframed the Curve modifier's Deform Axis, not sure why, so maybe delete the keyframe, and find the right axis (which seems to be -X)

Your stalk doesn’t completely follow the curve but it’s because it is not originally completely straight,  it’s already a bit curvy before you give it the Curve modifier


Sculpting Shape Keys with Multires Modifier?

I believe shapekeys can only modify the base mesh. Changes made to higher multires levels are not affected by shape keys. If in the multires settings Sculpt level is 0, you are sculpting the base mesh. When in the video he says "apply sculpt to base mesh instead of multires layers", he means you should sculpt the base mesh only, not higher multires levels.
Friend3D, by saying multires with shapekeys worked for him, perhaps means that modifying base mesh with shape keys didn't break higher multires levels in his test. It always used to break when that was done before Blender 2.9, though I'm not certain it doesn't sometimes still do that.


Way to disable "gradient" in ortho views?

Modal Timer Handler,

Run script, adds a button to info header.  Uses no gradient in ortho mode and gradient in perspective view for all 3d views on screen when ON.  Add a comment if you want changes re side view etc, or setting a default, prob gradient on when OFF.

wm.event_timer_add(2.0, context.window) makes it tick over every 2 seconds. Change for faster / slower updates.

import bpy
from bpy.props import BoolProperty

class ModalTimerOperator(bpy.types.Operator):
    """Operator which runs its self from a timer"""
    bl_idname = "wm.modal_timer_operator"
    bl_label = "Modal Timer Operator"

    _timer = None

    def modal(self, context, event):
        screen = context.screen
        theme = context.user_preferences.themes[0]

        if not screen.toggle_grad:
            self.cancel(context)
            return {'CANCELLED'}

        if event.type == 'TIMER':
            views = [(a, s) for a in screen.areas
               if a.type.startswith("VI")
               for s in a.spaces
               if s.type.startswith("VI")]

            for a, s in views:
                theme.view_3d.space.gradients.show_grad = s.region_3d.is_perspective

        return {'PASS_THROUGH'}

    def execute(self, context):
        wm = context.window_manager
        self._timer = wm.event_timer_add(2.0, context.window)
        wm.modal_handler_add(self)
        return {'RUNNING_MODAL'}

    def cancel(self, context):
        wm = context.window_manager
        wm.event_timer_remove(self._timer)

def register():
    bpy.utils.register_class(ModalTimerOperator)

def unregister():
    bpy.utils.unregister_class(ModalTimerOperator)

if __name__ == "__main__":
    register()

def theme_gradient_toggle(screen, context):
    if screen.toggle_grad:
        bpy.ops.wm.modal_timer_operator('INVOKE_DEFAULT')

bpy.types.Screen.toggle_grad = BoolProperty("Auto Gradient", update=theme_gradient_toggle)
# draw a button in the info header
def draw_button(self, context):
    screen = context.screen
    text = "ON" if screen.toggle_grad else "OFF"
    self.layout.prop(context.screen, "toggle_grad", toggle=True, text=text, icon='RADIOBUT_%s' % text)

bpy.types.INFO_HT_header.prepend(draw_button)
#bpy.types.INFO_HT_header.remove(draw_button)


OS X 10.11.4 Intel Iris Pro - OpenCL Build Fails with GPU Rendering

No, AMD are not the only system GPGPUs that support Cycles OpenCL Rendering.

https://wiki.blender.org/index.php/OpenCL

But you are not alone. In OS X 10.11.4 with Iris Pro 6100 on the Macbook Pro 13" the kernel fails. The OpenCL support by Apple for the iGPU is OpenCL 1.2. It should work, but fails.

That onus is on Blender.


Force edge split even when angle is zero

I'm not sure you can do it without first applying at least the Triangulate modifier, but it can be easily done in edit mode. (If I interpret things correctly, the Split Angle of the Edge Split modifier is taken as greater than, not greater than or equal to, so you'll have to mark all edges as sharp, and I know of no way to mark edges that are created by a modifier sharp without first applying that modifier).

Method 1

Apply the Triangulate modifier, Tab into edit mode, select everything by pressing A as many times (none, one or two, depending what's selected to begin with) as needed and mark edges sharp (Mesh -> Edges -> Mark Sharp or CtrlE followed by K).

Method 2

Remove both your modifiers, then Tab into edit mode, select everything by pressing A as many times (none, one or two, depending what's selected to begin with) as needed and triangulate (Mesh -> Faces -> Triangulate Faces or CtrlF followed by T), then split the edges (Mesh -> Edges -> Edge Split or CtrlE followed by D).


Locking a vertex group from modification

I think you outlined most of the the good ways, but here is another option:
Mask modifier:
You could try using the Mask modifier:

Add a mask modifier, select your vertex group and enable Invert so the vertex group is hidden.

Enable Edit mode visibility and Apply to edit cage so that there is no way to select the vertex group elements in edit mode:

This will basically function like hiding geometry, except it gives more control and does not interfere with normal hiding.
Note that it does not work in sculpt mode (hidden geometry will still be sculpted)
Shape keys:
However, I Think Shape keys is the way to go as it works for both modeling and sculpting.
To set this up:

Add vertex group of all the geometry to want to modify (excluding the geometry you want to lock)

Add two shape keys, a Basis and a shape key. Set the Value of the shape key to 1 and do your modeling sculpting etc.

Set the Blend group to your "modifiable" group. Now only the modifiable geometry will be moved to the new shapekey position, the rest will remain in the Basis position:


How can I get import an .FBX point cache animation to Blender?

Blender's FBX toolset doesn't support point cache data.  So you'll have to separate out the mesh from the point cache.  Just export the object as an FBX, then save out your point cache in either the LightWave .mdd or the 3DS Max .pc2 format.  You can then apply the point cache back to the object in Blender by using the Mesh Cache modifier.

However, if you simply want to transfer the model and animation, you can try using Alembic, which from what I saw in your video, C4D can export and Blender can import.

Cheers!


This happens because of difference in location of armature origin , in Object and Edit Modes.
Simply reapplying armature location , will sync it in both modes.


One of your face is reversed, you need to recalculate the normals (in Edit mode, select all and ctrlN).

I guess it messed up with the bevel because bevel uses the orientation to create the bevel profile, so two faces with opposite normal orientation > bug.

Anyway, here is a way to do it:


How to make certain objects not effected by a light source. Cycles

If there is only one light within the entire scene you could set the material that object has to shadeless.


added cylinder looks like it's the wrong size

Turns out this was caused by a "solidify" modifier that I had on the object I was editing.  Applying the modifier or deleting it before adding the cylinder solved the problem.


As probably one of approaches is to use one cube for this animation with multiple Follow Path constraints added.

In the example below I added 5 different curves, and 5 different Follow Path constraints for the cube.

I used Offset option (thus animated it) in all constraints except for the first one (and actually for the circle, for some reason). I also animated Influence option of every constraint to make every one of them to work separately.

To bake this action to keyframes and get rid of constraints you should select that cube, hit Space and enter Bake Action (or 3D View > Object > Animation > Bake Action). In the options you should select Visual Keying and (optional) Clear Keyframes - you won't need them:

based on this answer


By default cycles samples one lamp at a time. The black spots likely correspond to samples where cycles was attempting to sample lights which are doing nothing for actually illuminating the visible objects.

You could try disabling Multiple Importance Sampling on lamps/materials you know won't contribute much to illuminating the scene, and/or play with the Light Sampling Threshold in Properties > Render settings > Sampling.

However, if that doesn't cut it, then you can use the Branched Path Integrator, which allows for sampling all lights at once:

Note that it works a bit differently from the default integrator, so try playing around with the settings to see what works.


How to display names of objects in viewport

Select all objects by hiting A. Then in the
Properties areas Object tabs Display
group check the checkbox Name for name display.
Then right click the checkbox and select the option
Copy To Selected. Works on almost all options.

Edit: In current versions, using alt-click on
properties applies them for every selected object.


I tried to merge 2 vertices, but it keeps moving to the center

This could be related to the mirror modifier. If the body was made on the right side and the horns on the left, they look ok, but the real vertices are on the opposite sides. Deactivate your mirror's visiblity to check this.

You should work with the "Adjust Edit Cage" of the mirror modifier disabled to avoid creating things hard to merge.


What would be the easiest way to UV map a complex object?

Model your own UV Map

This technique allows precision control over the geometry of your layout by unwrapping from a Shape Key pose.

"Project From View" allows anything we are looking at in the 3D Viewport to be stamped into 2D space (a UV layout). The trouble is that even if we can get a good projection angle there are usually some pieces of geometry on the other side of the model that will overlap in 2D. The solution I came up with is to model exactly what gets projected. Luckily UV projection takes Shape Keys into account, and we can reseal a ripped mesh without doing harm to the UV Map.

While it is powerful, this approach is not the most appropriate solution for every case. It is best to become familiar with the traditional UV unwrapping methods because often those will suffice. For example, if you have a cylindrical shape then Cylinder Projection is probably the best approach. The following technique is for getting at the hard-to-reach places and it can spare you many UV mapping headaches. It seems the standard unwrapping techniques weren't enough in your case, so hopefully this will help you.

Save a backup copy of your mesh and let's begin.

1. Rip it

Select the edges where you would normally mark seams and instead rip the vertices V, then press Esc to snap them back into place.

You can then select any individual piece or "island" by selecting a single part of the geometry and then Selecting Linked (CtrlL).

Another way is to mark all of your seams first (CtrlE > "Mark Seam"), then select a face and choose Select Linked (CtrlL). The selection will by default be delimited by the seams. (This must be done using Face Selection, not Vertex or Edge Selection.) Then choose Select > Select Boundary Loop, and Rip (V).

2. Add shape keys

From Object Mode, in the Mesh Context, add a shape key for the base mesh, then a second one. Label the second one "UV" and make sure it's selected before proceeding.

3. Flatten it out

In Edit Mode, Edit your model to be flat and fit nicely within a square area. Actually, it doesn't need to be totally flat as long as it appears flat from the projected view angle - that is, no faces overlapping. I found it easier to manage flattening each piece as I finished it. To flatten simply scale along the axis you will project along. In my example it would be SYNum 0. Of course it's not just a matter of flattening, but modeling it into a shape with no overlap and then flattening.

The goal is to end up with a mesh that is flat in its "UV" Shape Key:

This step is a modeling process that will vary from model to model. Here are a few of the tools you will probably find useful during this process:

Select Linked CtrlL - Selects all connected geometry. Use it to select each "island".
Hide Unselected ShiftH - Hides everything except what you have selected.
Unhide AltH - Puts hidden geometry back in view.
Proportional Editing (Connected) AltO - Influences the verts around your selection too.
Shrink/Fatten AltS - Pushes out or pulls in selected geometry relative to the Pivot Point.
Edge Slide GG - Slides an edge loop toward or away from neighboring edge loops.

Remember: Do not add or remove any geometry. When editing a Shape Key pose you are only pushing verts around, not adding, deleting, welding, or extruding. Reshape the geometry by moving positions of the vertices, that's all.

Make sure face normals are pointing toward the direction you will be looking from when you project your UV layout. Do not simply flip the normals. Instead rotate the piece to be facing the correct direction - outer part facing forward.

An animation showing the shape key transition of a model from 3D to 2D for UV unwrapping:

For hard surface modeling especially, such as with the model in your .blend, you will want there to be minimal stretching. So whenever possible, instead of stretching, rotate with the 3D Cursor as your Pivot Point.

Also, for hard surface modeling you have the luxury of separating large mesh objects into smaller, more manageable ones. Separate in places where you can hide the seams, or where seams occur anyway, such as where panels connect. You can then make a UV Map for each object. Each object can have a maximum of 8 UV Maps.

4. Unwrap

Method 1: The simple way

Put your 3D Viewport in Orthographic view. Look at your flattened mesh straight on and Unwrap (U) using > "Project From View". Scale it to fit nicely within the square grid of the the UV/Image Editor.

Method 2: Unwrapping for symmetrical objects

One limitation with Shape Keys is that modifiers cannot be applied while the mesh object is using them. So if your mesh has symmetry generated by a Mirror Modifier, project onto just one half of the UV area. To get the projection perfectly centered, set your Camera to Orthographic, make the dimensions square, and make sure the camera is directly aligned with your object. Enter Camera View (Num 0). The unwrapping will use the camera's bounds as the UV Map bounds. Press U and choose "Project From View".

5. Adjustments

At this stage you can refine the UV Map.
You can grab, rotate, and scale the UV islands to pack them together more efficiently. You may want to check your UV density by creating a UV Grid and nudging the verts of the UV Map so that the size of the texture becomes uniform over the model.

Do an incremental Save As, because next comes a destructive edit.

6. Piece it back together

From Object Mode, delete the shape keys. First the "UV" shape key, then the "Basis" shape key.

From Edit Mode, select the entire mesh, press W, and select Remove Doubles. The vertices we ripped before are now mended.

Applying the Mirror Modifier on symmetrical objects

If your mesh object is using a Mirror Modifier you can leave it on for now in case you want to keep your options open. But if or when you would like to texture the left and right sides differently you will need to apply the Mirror Modifier. (Note that if you plan to use a normal map the two sides must be unique in order to avoid shading problems; the normal map cannot simply be mirrored the way a diffuse texture can.)

Apply the modifier from Object Mode, then from Edit Mode select the newly generated half of your model, including the center vertices. The selected vertices will show up in the UV/Image Editor, however they are lying directly under the vertices that were originally projected. To flip them over to the opposite side, place the 2D Cursor in the center of the UV area on the X axis, set the Pivot Point to be the 2D Cursor, then scale -1 along the X axis.

And that's it, now you have a UV Map that looks exactly the way you want!


Don't have ADD IMAGE SEQUENCE option in Texture ( Shader )

In the Shader Editor you can find it under Add -> Texture:

In the Compositor under Add -> Input:


A problem opening old (non-filmic) VSE only .blend files when Filmic is installed?

I see you are using v2.68, try updating to the newest release.

https://github.com/sobotka/filmic-blender/issues/24


Import 3D model from CityEngine into Blender and edit UV Map

To UV Unwrap your model, Go to Edit mode of your object and select all the mesh, then press U on your keyboard to open UV Mapping options and select smart UV project,

after change your window mode to UV mapping,

and finally open the texture you want to give to your object in the bottom bar,

once you opened you can scale and move your UV map untill it matches your texture how you want it.To scale press S key, to move press G key


How to create proper displacement for weld joints?

You said you wanted a to do this procedurally, but I personally would recommend using an image texture like this one.

This image was created by me, and is in the public domain. Use it however you want :) Click for larger size

This displacement map produced a result like this:


Why is part of the object a different color than everything else?

The normals are inside out. You need to flip normals. Press CtrlN in edit mode.


Creating a create tilable displacement map

Here are 3 solutions:

Displace modifier (but it will be hard to get sharp angles, I guess Displace modifier is good to make more organic surfaces):

Unwrap your surface.
Give it a Subdivision Surface modifier with a Subdivisions value of 4.
Give it a Displace modifier. Choose Texture Coordinates > UV. Load your texture in the Properties panel > Texture (I've used one of yours and convert it to a DISP with CrazyBump), and select it in the modifier.
Put a second Subdivision Surface  modifier below the Displace modifier.

Tissue addon:

Install the addon.
Create your pattern object, create your 3D surface.
Select your pattern object, then your surface.
Open the Tools panel > Create tab > Tissue, click on the Tessellate, choose the options you want, validate with the OK button.
You have a new object. You'll probably have to remove doubles.

You could also try Duplifaces but it won't work for every kind of pattern:

Select your pattern object, parent it to your 3D surface.
Select your 3D surface, go in the Properties panel > Object > Duplication > click on Faces, activate Scale and choose the Inherit Scale value. If your surface has a lot of faces you'll have as many duplications.
To make the object editable, press shiftctrlA.


How do you make an SSS texture (Using Principled BSDF) only affect part of a mesh? (Image/gif inside)

The best way I can think of is to have Image Texture for Subsurface value which will behave as a SSS intensity control. Where black color = 0 and white = 1.

In my example I've used such setting with two textures, one for SSS color and another one (black and white) for SSS intensity. This way you can control where SSS will be visible (and how intense).


Why is my cloth not subdivided correctly in the rendered image?

So as it turns out, while I had increased the Subdivision in the Modifier Stack to 6 for Viewport, I had failed to change it from 2 for Render. (In the following image I have changed the Render Subdivisions from 2 to 6)

Thank you to the commentators, error lay between keyboard and chair.


How do you undisable in viewport all object in a collection?

Pressing H will hide the selected objects from viewport, Alt+H will unhide all objects in viewport.

You can also right-click the collection in the Outliner, and select Visibility > Show All Inside


Is there an add-on for a knife-like tool for curves?

No there is not. Unfortunately there are very few cad-like tools for bezier curves in blender. Curves are kind of a second-class citizen, and although they have improved considerably in recent years, they are still not regarded as primary modeling tool.

The closest I know you could currently get is probably a relatively recent addon "Extend / Trim Curve CAD Tools for Bezier Splines" which works relatively well for most situations:
http://blenderartists.org/forum/showthread.php?387520-Addon-Extend-Trim-Curve-CAD-Tools-for-Bezier-Splines


Considering your mesh vertices are approximately centered around the object origin (if not, this will not work as expected with this solution), you can use this kind of setting:

From the object output of texture coordinate (which gives x,y,z values relative to the origin).

Calculate the distance to the center (dot product then square root).

Subtract some value which may correspond to the inner orange part distance to the origin.

Input this result into a colorramp tuned to mix yellow/orange appropriately.


(procedural) Edgewear for (procedural) real Microdisplacement? for Cycles

So there are several ways to do what you are trying to do, some only work with Cycles.

The first one is the one you cite which mixes the (Input) Geometry > Normal output and Bevel nodes into a (Converter) Vector Math in Dot Product mode:

You can use the Geometry > Pointiness output:

Or the (Input) Ambient Occlusion node (it works with Eevee, you'll need to enable the Ambient Occlusion option in the Properties panel > Render:

To make the effect more natural you can mix it with a Noise or another texture, here through a MixRGB in Lighten mode:

All these black & white textures can be used as factor in a Mix Shader or MixRGB node in order to mix two sets of nodes.
At last you have some group nodes like the one you cite and that you can upload. There is the Mask node, as explained here, and the Edge Detect node, as explained here, both created by Wayward Art Company.


how to turn off moving objects by holding RMB?

Go to User_Preferences->Input->Mouse->Tweak_Threshold and set it to higher value :


As you guessed, you can accomplish this using Force Fields, which by default interact with hair particles that have Hair Dynamics enabled.

I recommend trying the generic Force, which tends to well for most cases that need a uniform radial force. To have the field attract hair instead of repel, you need to set the Strength to a negative value.


You probably won't get many recommendations about books here, because they would be very opinion-based.

A long time ago I myself thought that books about software are way better than tutorials. After a short while I gave up on them.

My main reasons were that

books about software (especially FLOSS) become outdated quite fast.
most of them go through a tedious description of all the functions without showing much about how to use them properly.
doing more complex tasks often require techniques that won't be shown in most books unless they are written with the advanced user in mind.

My recommendation for beginners:

Start by learning Blender's basic functionality by watching video tutorials (like this one by Sardi Pax). Seeing things in motion teaches you much more about complex software than just a bunch of screenshots with some paragraphs of text that are possibly stretched over several pages.
Learn the basic techniques like extruding, subdividing, connecting different primitives, then proceed to basic materials (colors, textures, shaders). Start with Blender Internal renderer before going through complex Cycles tutorials.
Start with basic models and work your way up. Do not expect to be able to create complex 3D models, renderings or animations after two hours, days or even weeks of reading a book or watching tutorials. Every 3D software is complex and Blender is no exception.
Be prepared that learning 3D modeling isn't something that's ever completed.

You also should check out the link in Shady Puck's comment above (Resources for Blender). It's a constantly growing source.

Some "big" names you might want to check out are agenzasbrothers, Andrew Price from BlenderGuru, Gleb Alexandrow from CreativeShrimp, masterxeon1001 and Darrin Lile (he's in the link collection Shady Puck mentioned above with some very good tutorials about character creation and animation). Most of these guys are producing new videos at least on a monthly basis and some also have informative stuff on their websites.


Requiring OpenGL 3.3 for a Blender 2.8 scene but not the application

Ok, so I have been fighting with this in many programs as well as blender, I think the problem is on Nvidia's side.  If you open the Nvidia Control Panel, you can specify the GPU to use for OpenGL.  This solution worked well for me and I don't have any more problems... yet.  Hope this helps.

Right click desktop > Nvidia Control Panel > Manage 3D Settings > OpenGL Rendering GPU > (specify only one, don't use Auto-Select)

Now click Apply and you should be good to go.


How can I animate these planes for Unity game Assets?

Is it your plan to just rotate arms and legs as if It where 2D pixel art?

Use the timeline (the meter with the frame numbers and the green line indicating current position, at the bottom) to go to say frame 25. Now rotate the legs to pose the character as if it were walking, press key "i" to insert a new keyframe, in the menu that just appeared click on "LocRotScale", now drag the green line in the time line from 25 to 0 and from 0 to 25 again, watch how your character walks. Apply this to do more complex movements.

The good thing is that you only need to pose the character in the initial position, then advance x number of frames (depending on how fast you want the movement to be) and pose it in the final position and insert keyframe there. The frames in between will be extrapolated by Blender. You only need to insert more keyframes in the middle of a movement to do more complex movements.

Also, you probably want linear extrapolation of keyframes: How do I make animations a steady speed?

Yes, you can use the Action Editor to save each animation as actions but... I would not trouble myself into do so, I would just save all animations as a continuous very long time line. If you will export as a 2D spritesheet that is precisely the more practical to do. If you will use it as 3D assets maybe you need the actions in order to trigger them by action name from the game engine code.

I don't sure about the state of .blend files support in Unity, I don't know If It will import the actions at all.

No, you don't need to merge all planes into one object. Actually, by having them as separated objects, you can insert keyframes for each plane individually and move them independently. If you join everything into a single object, you will have to use an armature to animate legs and arms (because I think that changes done in Edit Mode to the mesh are globally applied across all keyframes making it impossible to create keyframes by rotating things in Edit Mode. While poses done with armature can be keyframed).


If you baked a sound file to the text location an rotation channels, then try deleting the affected animation channels in the graph editor. Then you should be able to insert keyframes again.


How do I use shape keys and bones for a Facial Rig?

This is a fairly broad question, So I'll just outline the overall workflow and the reasoning. I also assume you are already familiar with basic rigging concepts including bones, shapekeys, drivers, constraints and weight painting.

Firstly you need to understand the pros and cons of bones vs shapekeys:

Bones generally create better intermediate shapes as they generate a curved path for the vertices to follow and the maths for blending between each other is already built in. However, they are much trickier to create very specific shapes as you have limited control of how a bone moves vertices.
Shape keys can create any shape that you can model, but you have to manually specify how to combine them using drivers, and the vertices move in a linear path between the basis and the shape, so intermediate poses can look often odd (although sometimes this is desirable).

In general you want to create a rig to support your basic movement with bones, and then use shapekeys to correct the pose in various positions. These shapekeys should then be controlled using drivers based on the bones positions.

To create a bone rig for a face you will probably want to add the following:

A bone to control the jaw motion, this can be a simple bone that you rotate to open and close the jaw, or a much more sophisticated setup as you become more advanced
A bone for each eye to control the direction that they are looking. These bones should pivot around the center point of the eyeball. The damped track constraint can be used on these with a target object or bone to give a controller that you can drag around as the position of the eyes' focus
Bones for each eyelid that rotate around the pivot of the eye bones. These allow the eyelids to follow a curved path so that they don't clip through the eye.
Various bones simulating facial muscles using the stretch to constraint to provide volume effects. These can either point to controller bones and/or be parented to other bones to allow posing and accurate movements. Making these bendy bones can get better curving effects like real muscles. Setting these up is fiddly, so I suggest you look at some other facial rigs for examples.
A chain of a few bones to control the tongue.

For shape keys you will probably want at least the following:

Corrective shapes for the eyelids opening and closing, as just bones generally won't give quite the right shape at the extreme poses
(corrective) shapes for mouth expressions and phonemes. The number and setup of these will depend on what you have done with face muscle bones previously, and it is possible to do these poses with only shapekeys and no bones if you wish.
(corrective) shapes for eye and brow expressions. The number and setup of these will depend on what you have done with face muscle bones previously, and it is possible to do these poses with only shapekeys and no bones if you wish.

There is plenty more details about each step and small tips and tricks to achieve different effects, however they are all better off as their own specific questions.


Can I set key to only the key attribute that I move the bone along with?

Yes.  If you right-click on the Z value in the N panel you get a menu, and one of the options is Insert Single Keyframe


To have proper topology and avoid overlapping faces, create a loop cut on the two columns, one cut on the bottom of the left column, and one and a cut on the top of the right column.

Then select the newly created faces on the inside and do Bridge Edge Loops to join them with new faces.
(the shortcut is Ctrl+E and select bridge edge loops)


It sounds like you might have had an issue with migrating a file from 2.80 to 2.81, but hopefully this helps someone else doing weight painting in 2.81.

In 2.81 with left click select, you should be able to select bones in Weight Paint mode with Ctrl-Left Mouse. You shouldn't need to switch to Pose mode to pose any bones.

For completeness, my full set of steps is:

Select the rig
Shift-select the mesh
Switch to Weight Paint mode
Use left click to paint + Ctrl-left click to select bones


Procedural square shape in Cycles (with similar effect to Gaussian blur)

Here's an alternative solution using maths nodes to calculate distance from the square and the Gaussian distribution function.

The key here is for any point in the shader to calculate the closest point to the square. The square is defined by 4 boundary values - X-Min, X-Max, Y-Min, Y-Max.

To calculate the closest point that is still within the square we can simply use the Max and Min functions. ie,

closest-X = Min( Max(X, X-Min), X-Max)
closest-Y = Min( Max(Y, Y-Min), Y-Max)

To calculate the distance to this point (ie, the closest distance to the square) we can use Pythagoras

distance^2 = X^2 + Y^2

ie,

distance = sqrt(X^2 + Y^2)

For the Gaussian falloff we use the equation :

 intensity = 1 / (2^dist)

Bringing it all together produces the following material (note that I've omitted the 'sqrt' of the distance calculation - this gives a more pronounced falloff based on the square of the distance, rather than the plain distance) :

Adjusting the input nodes (X-Min, X-Max, Y-Min, Y-Max, Focus) will adjust the size and 'blurriness' of the square. Note that the Gaussian blur starts from the edge of the square - so the square is always maximum intensity with the falloff starting at its boundary. This means that the blur will always make it appear larger - adjust the boundary values to compensate whilst adjusting the Focus if this is not desired.

To tile multiple squares you can simply use a Mapping node and Modulo nodes to repeat the range multiple times :

Animating the mapping and various inputs can produce the following result :

Blend file attached

This can be used to generate procedural tiles as shown by this sample image provided by @cgslav :


Why does the UV/Image Editor remain empty after UV unwrapping?

I found my problem in an answer to this question. I had to click the X beside the Render Result, so it would display my UV Map.

Thank you all for your help! :-)


Texture Paint behaviour in regard to a Texture

Yes atomicbezierslinger is correct, you can do this by pressing the
Browse material to be linked button, then from the drop down menu, select your UV image you unwrapped from your object.

Similar to how you assign textures from a texture node in the Shader editor.


Puprlish Material with Blue Voronoi Cracks

You could use a Voronoi to mix between two shaders.

One seems to have a slight translucency effect while the other is opaque and glossy.

Use the same Voronoi to bump the shaders.


You have proportional editing on (the blue icon in the 3d view header) with a large proportional size (a large circle that appears when you try to transform) so when you try to move the duplicate mesh it moves the entire object and thus appears to have no effect, toggle it on/off with O or by going to the menu and choosing Disable.

After that to duplicate and separate, use Shift D, confirm with left click and then press P > Selection.


Use Console Entries to Drive Class Presets

You can look at the context.window_manager.operators collection.  The property settings are in the properties collection.  items(...) returns a list of key, value pairs

setattr(op, key, value)
# a key value pair of ("width", 3)
#equivalent of
op.width = 3

Put this in a draw method and it will list all operators by name, and if it's a bevel op expand on the call method as seen in the INFO panel and list the key value pairs.

    box = layout.box()
    for o in context.window_manager.operators:
        row = box.row()
        row.label(text=o.name)
        if o.name == 'Bevel':
            bbox = box.box()
            row = bbox.row()
            row.label(text="bpy.ops.mesh.bevel(%s)" % ", "
                     .join(["%s=%s" % (k, str(v))
                            for k, v in o.properties.items()]))
            for k, v in o.properties.items():
                row = bbox.row()
                row.label(text="%s = %s" % (k, str(v)))

Here is a modal timer operator that captures the bevel operator properties once it becomes context.active_operator to do something while it is happening.
(Test Code)

Put your mesh into edit mode, then run the operator, the operator will cancel when the user leaves edit mode, this can be changed.

Whenever a bevel operator is used it saves the settings to a dictionary on the operator, and while a bevel operator is context.active_operator prints the settings to the system console.

import bpy

class ModalTimerOperator(bpy.types.Operator):
    """Operator which runs its self from a timer"""
    bl_idname = "wm.modal_timer_operator"
    bl_label = "Modal Timer Operator"

    _timer = None
    bevel_operators = {}

    def modal(self, context, event):
        if context.mode != 'EDIT_MESH':
            self.cancel(context)
            return {'CANCELLED'}

        if event.type == 'TIMER':

            op = context.active_operator
            if op is None:
                return {'PASS_THROUGH'}

            if op.name == 'CSharpen':
                op.bevelwidth += 0.01
                if not op.run_modal:
                    #cancelled from CSharpen Operator update prop
                    self.cancel(context)
                    return {'CANCELLED'}

            elif op.name == "Bevel": # op.rna_type.identifier == "MESH_OT_bevel":
                key = hash(op)
                # save the operator props in a dictionary
                print("BEVEL", len(self.bevel_operators))
                print("bpy.ops.mesh.bevel(%s)" % " ,".join(["%s=%s" % (k, str(v)) for k, v in op.properties.items()]))
                self.bevel_operators.setdefault(key,
                                     {k:v for k,v in op.properties.items()})

        return {'PASS_THROUGH'}

    def execute(self, context):
        wm = context.window_manager
        self._timer = wm.event_timer_add(0.1, context.window)
        wm.modal_handler_add(self)
        return {'RUNNING_MODAL'}

    def cancel(self, context):
        print("Operator Cancelled")
        wm = context.window_manager
        wm.event_timer_remove(self._timer)
        # perform pre cancel here
        # print out the bevel operator dic

        for h, bo in self.bevel_operators.items():
            print(h, bo)

def register():
    bpy.utils.register_class(ModalTimerOperator)

def unregister():
    bpy.utils.unregister_class(ModalTimerOperator)

if __name__ == "__main__":
    register()

    # test call
    bpy.ops.wm.modal_timer_operator()

from code I set up from another answer to you where this operator talks to that operator "Csharpen"


Well, that probably means that you need to make the coin thicker. With the coin selected, tab into edit more. Press A to select all. Then press S to scale them. You might also want to make the coin's features (numbers, etc.) bigger as some fine details cannot be printed depending on the extruder size that company uses.

This issue is definitely not caused by the object being a hollow shell. As long as the mesh is closed, slicers will recognize it as a solid object. As a 3D printer owner, I can easily verify that.


How to apply a texture to only one side of a plane

In Cycles you may use a Backfacing output of the Geometry node as a factor for applying two materials for each side of a plane. Set up the material nodes as pictured below. You may do it in the same way in Blender Internal. The only difference is in BI the output of the Geometry node is called Front/Back.


Issue: EEVEE unexpected long initialization time while rendering

I had the same issue yesterday, when trying to render scene from animation in EEVE. It took about 25 second for it to start. It was the same with Cycles and Workbench render. There's no automatic update on blender so in my case it could be Windows or GPU driver issue. Tried previous blender release, same thing happended


How to assign material to solify modifier

What we see here is not the rim created by the Solidify modifier, but the thickness created by your Boolean object (here I made it visible, the solidify just make your object thicker but its rim is not visible).


How to color individual polygons in a low poly model?

That looks like it was done using vertex colors.

Go into Vertex Paint mode and apply your colors.  Note that faces will blend colors in a gradient based on their vertices' colors.

Then, in your Blender Render material, select the Vertex Color Paint option.


Multiple instances of blender (bpy) in single python script

Blender only allows one render to run in each instance. As a single render instance will normally use all available cpu's there isn't usually any benefit to running multiple renders at the same time.

If you do want to run multiple renders at the same time, you will either need to run multiple instances of your script or of blender.


Well, that was not easy for a beginner like me but I think I found a way. Explanations about lattice_index_from_uvw can be found in this question of mine. Just run the script once and then the handler bpy.app.handlers.frame_change_pre does the job.

import bpy
from math import cos

pi = 3.1415

lat = bpy.data.lattices['Lattice']
obj = bpy.data.objects['Lattice']

# Space

def lattice_index_from_uvw(lat, u, v, w):
    totu = lat.points_u
    totv = lat.points_v
    return w * (totu * totv) + (v * totu) + u

points = obj.data.points

Delta_x = points[lattice_index_from_uvw(lat, 1, 0, 0)].co_deform.x - points[lattice_index_from_uvw(lat, 0, 0, 0)].co_deform.x

x0 = [points[lattice_index_from_uvw(lat, u, 0, 0)].co_deform.x for u in range(lat.points_u)]

A = Delta_x / 3
Lambda = 10 * Delta_x

# Time

scn = bpy.context.scene

frame_start = scn.frame_start
frame_end = scn.frame_end

Delta_t = 1
T = frame_end - frame_start

def sine_wave(x, t, A, T, Lambda):
    return A * cos(2 * pi * ( (t / T) - (x / Lambda)))

def update_wave(t):
    for u in range(lat.points_u):
        for v in range(lat.points_v):
            for w in range(lat.points_w):
                points[lattice_index_from_uvw(lat, u, v, w)].co_deform.x = x0[u] + sine_wave(x0[u], t, A, T, Lambda)

def my_handler(scene):
    print(scene.frame_current)
    update_wave(scene.frame_current * Delta_t)

bpy.app.handlers.frame_change_pre.append(my_handler)


Blender 2.8: How to see multiple view layers at once in viewport?

According to the blog here: Blender developers blog in 2017

  An exciting future option for the 2.8x roadmap is to use View Layers as compositing units, also for real-time rendering. For simplicity now, we stick to having a single ‘active View Layer’ per Blender window.

And as far as I can see you still have only one active view layer in your blender window at this time.


cegaton's answer nicely covers the practical impacts of the size setting (i.e. the shadows), but what you are actually setting is the apparent size of the sun lamp.
In other words, the size controls radius of the sun as seen by the camera (or any other light ray), regardless of distance.

To see this in action, create a perfectly reflective plane and point a sun lamp straight at it:

Enable Multiple Importance Sampling on the sun lamp to allow caustics, then look straight down at the plane in rendered view (so that the sun lamp should be reflected back towards you)

If you are not in ortho perspective (in which case the sun lamp will appear infinitely large), you should see a circle which varies in size depending on the sun lamp's size setting.

This circle — a reflection of the sun lamp — shows that the lamp always appears the same size regardless of the distance to the camera, unlike the reflection of a sphere positioned a finite distance away:

In this gif the sphere is invisible to camera rays, so in rendered view only its reflection is visible

So you could say the sun lamp size is defined in camera space, rather than world space.


This is because you have Smooth shading enabled in your 3D Viewport > Toolshelf > Tools tab > Edit dropdown > Shading:. There is a way to fix this without going back to Flat shading.

Go to the Properties panel > Object Modifiers tab and add an Edge Split modifier. The default settings should be ok, but if they aren't, you can change the Split Angle:, which is defined as the max value at which an angle should be split.

The Edge Split modifier:

Comparison with a cylinder:


How to convert HSV to RGB using shader nodes?

Is this an exercise,  or ....

... will this do?...
EDIT: No, it won't. If you want to do logic like this by hand..
One way to approach the case statement would be use the implicit cast of True and False to 1 and 0, and multiply the truth-value of the case-condition with the color that would result if it were true.

.. so the above cluster says (v,t,p) * (i == 0) + (q,v,p) * (i == 1) +....
If the i == 0 condition is true, then the (v,t,p) contributes to the sum of colors. If the condition is false, it contributes (0,0,0).  Only one case will be true, and contribute more than 0 to the sum.
You then accumulate a sum of all the colors:

But this stuff can be tedious to debug.. @Rich Sedman's kit can be a fantastic time-saver.


How to turn off mirror to Image texture in UV editor

You can't have custom texture coordinates for both sides of a mirrored object, since they - as well as the geometry are created by the modifier.
You can however choose how to mirror the UV islands in the modifier's settings, using the checkboxes for flip U and flip V. They should about get you there.
If you need to apply completely idependent UVs, you will have to apply the modifier. If you want to texture paint, and issues with the modifier arise, you can safely duplicate your object, apply the modifier on the copy and paint on that one, deleting it once you're done.


2 GPU different technologies Maxwell and Pascal Rendering Together

Yes it is possible. Nvidia CUDA is supported for GPU rendering on Nvidia graphics cards. Supported graphics cards start from GTX 4xx (computing capability 2.0). Both of your listed cards have compute capability 2.0. For them to work all you should need is the latest Nvidia drivers.

Source: The Blender Manual


Why does Blender gets frozen once I rotate an object and then crash?

I suggest deleting all evidence of Blender from your computer and trying to reinstall. it may be a fact of repeated downloads or simply that your computer's software is not designed on the same framework as Blender. it may also be an idea to clean out your computer as it may be a stray program interfering with the startup. check in detail the running requirements of Blender before installing and make sure that instillation.
It may very well be that your software cannot handle blender, or that you somehow managed to download a damaged version of the files


In the modifiers tab, any modifier that's in use has 4 buttons: Visible in Render, Visible in Object, Visible in Edit, and Vertex selectable in Edit mode. Press the last one, the one with the form of an inverted triangle. That should make the mirrored part be selectable in edit mode. Anyways, whatever you select there will also automatically be selected on the other part of the mesh that's the original mirrored and vice versa, because they are mirrored. Making seams on whichever of them will make the seam on the other, even if you did not select the mirrored vertex to be visible in edit mode.


I don't see graph in Graph Editor window

Because you are looking a video made on an older version of Blender which had the driver edition as a sub-part of the graph editor, whereas the current version has separated them into two distinct editors.


Have you checked the cycles hair settings? The 'shape' option of the hair settings could play a role. Try typing in -0.75 in that area to change it. Are the roots too big?


Node wrangler not appearing even when enabled in User Preferences

Looks like in this version, it's simply in the left-hand panel rather than the right-hand one (not sure what their proper names are):


How to add a specific amount of loop cuts without the mouse

Yes you can. Here's how:

with the element selected, hit → Tab
hit ⎈ Ctrl + R and hover your mouse to activate the loop visualiser
hit 5 (if you want 5 cuts)
hit ⏎ Enter
enter a number between -1 and 1 to define the offset of the cuts, or use the arrow keys to move them in increments
hit ⏎ Enter


transparency texture problem with particle system (shows wireframe)

Those are Freestyle outlines. If you don't want them you can turn Freestyle off in the Render tab of the Properties panel. Or, if you want them but you don't want them on those particular meshes, you can add a Material stroke modifier under the Properties panel->Render Layers tab->Freestyle Line Style->Alpha. Then set the Freestyle stroke alpha to zero in the leaf material. Or, you can model the leaf shape more accurately and stop using alpha on that material entirely. This would help a lot with the problems you're having with the mist, too, and I would personally recommend that you model the silhouette of the leaf a little more meticulously to help with that.


How do you model a ground plane to match the height of a premade object?

just subdivide your plane and in edit mode activate proportional editing then just drag the vertices or faces to whatever height you want then in object mode shade it smooth for nicer look. Look at some modeling tutorials online it will help you a lot.


Blender 2.8 - Sprinkles particle are not visible when rendered

I think you need to click the camera icon next to the Sprinkle collection for it to show up in your render


How to prevent legs from stretching when moving other parts of body?

There are some tips to fix your problem.

subdivide
weight paint
preserve volume

1. subdivide

For a "good" rigging, your model seems to be too low poly. I suggest you add some loop cuts (near the joint) or add a subdivision surface modifier above the armature modifier.
Make sure that your new vertecies have appropriate vertex weights.

2. weight paint

By using weight painting, you can manipulate "the influence of the bone on a certain vertex". If some of your vertecies seem to move too much, decrease the vertex weight, mainly at the vertex paint mode.

3. preserve volume

At the Armature modifier panel, there is a check box labeled "preseve volume". Ticking it may improve your armature deform.


Play audio file when scene starts but don't play it again if leaving scene and coming back

Do not come back to the start scene. There is no reason to do so. The start is done, so the player should continue with the next steps. (Unless this is what your game flow is supposed to do.)


I would suggest not relying on the physics engine at all and instead place them manually.  Just like an actual jewler, they wouldn't repeatedly throw jewlery down until it looked just right, they would place them exactly where they want them.  It sounds like a good exercise in using the rotation axis shortcuts!
x
y
z


Is this bug or why my model ruined in sculpting process?

Some of your normals are pointing the wrong way.
To fix this press:

A to select everything
↹ Tab to enter Edit Mode
⇧ ShiftN to recalculate the normals on the outside


You've set a View Clipping Border

View Clipping Border (⎇ Alt +B)
Allows you to define a clip/ping border to limit the 3D View display to a portion of 3D space. It can assist in the process of working with complex models and scenes.
Once activated with Alt-B, you have to draw a rectangle with the mouse, in the wanted 3D View. It becomes a clipping volume of four planes:
A right-angled parallelepiped (of infinite length) if your view is orthographic.
A rectangular-based pyramid (of infinite height) if your view is in perspective.
Once clipping is used, you will only see what’s inside the volume you have defined. Tools such as paint, sculpt, selection, transform snapping, etc. will also ignore geometry outside the clipping bounds.
To delete this clipping, press ⎇ Alt+B again.
The dark gray area is the clipping volume itself. Once clipping is deactivated with another Alt-B, all of 3D space will become visible again.

From the manual, that most ignore, but contains useful information for those that still remember how to read.
https://docs.blender.org/manual/en/2.79/editors/3dview/navigate/clip.html


How do you exchange an object/mesh between two separate rigged armatures

To hold and drop an object, here is the basic operation to do:

Give the object a Child Of constraint, press Set Inverse so that it stays in place.

Make the parent move from point A (at frame 0) to point B (let's say at frame 20).

The frame before the frame where the dropping is supposed to happen (let say frame 9 as the dropping will happen frame 10), select the child, create a location keyframe and keyframe the Child Of constraint Influence at 1.

The next frame (so, here, frame 10), where the dropping happens, keep the child selected, create a keyframe Visual LocRotScale (or simply Visual Location), so that the new location is the one currently seen on the 3D view. Also keyframe the Child Of constraint Influence at 0 so that the object is not the child anymore.

Now as you give the object to another one, just give this object a second Child Of constraint with the new parent. At frame 9 you'll keyframe the Influence at 0, at frame 10 you'll keyframe the Influence at 1, and now the the child has a new parent.


You can use the metadata to do that:

Go to the output properties and to the metadata section.

Then choose the date and activate 'burn into image':

You can obtain something like that:

That can also be customized using Python as described in this answer.


While having the magic one button solution is enticing the old manual approach can give more control using basic modelling techniques.

Start by removing the unwanted edges.

See how many vertices you need - you can optionally add corner edges to clarify the targets. In this example I need to add three more vertices to each edge.

Use CtrlR to add more edge loops - use the mouse scroll wheel or + and - on the numpad to change the number of cuts being added.

Select all the vertices in two edge loops to be filled in.

Choose Grid Fill (2.69 or higher) - this is available in File->Faces->Grid Fill or search after pressing space.

For versions before 2.69 you can use Bridge Edge Loops - File->Edges->Bridge Edge Loops or search after pressing space. This is still available in 2.69. You may find this works better in edge select mode without any corner connecting edges being selected, while grid fill works better if you have the corner edges in place.

The grid fill initially uses the order the vertices are selected to fill in the faces, if you initially get a strange fill you may want to press F6 (also available at the bottom of the toolbar T) to adjust the Offset until it fills in nicely.

You can also adjust how the bridge edge loops works

Repeat for each side. This gives you a nice final topology

You can also adjust this along the way by adding lop cuts between the two edges. The bridge edges has the option to do this for you and the grid fill will join these edges when you fill in the last two sides.

If you want the same result on the opposite side, if both are the same, you can select the top vertices and duplicate them, move to the opposite side using snap to vertex to align them and remove doubles to join together.


Is it possible to symmetric weight-paint an asymmetric mesh?

EDIT: According to person asking this question, this is the exact opposite of what they wanted, all i can say is just tick it on instead of off, but they said that doesn't work, i shall keep this up for those who find it though.

This is because X Mirroring is on, to turn it off go to into the Weight Painting mode on your desired object.

On the left Toolshelf T select the Options(1) tab.

Under Options(2) Uncheck the checkbox labeled as "X Mirror"(3)

Your weight painting should be fine now!

Tip: open up a new file, without changing anything (other than what i'm saying now), even moving the camera, repeat the steps above and then with the mouse over 3D view, press CTRL+U and then press "Save Startup File"

This makes your blender startup file have what you just did already done, so you don't have to do it again.