I opened up Blender the next day and now the bisect tool seems to work fine. I guess I just needed to close and open Blender for the tool to fix itself. Kind of frustrating that a bug like this exists, but it was an easy solution and I can't expect a huge update like this to work perfectly. Hope this helps anyone else with similar issues!


How to make this animated texture seamless from a 2D perspective

Tiling 4D Noise in 2D
Since Blender has given us 4D procedural noise textures, it's been possible to tile them without distortion in 2D.
We can map the given 2D X and Y onto two orthogonal circles in 4-space. As we loop around them, we return to where we started. (It's possible to map the plane onto a 3D torus in the texture's 3 space, but distortions result: the major and minor radii of the torus are either different, giving uneven scaling, or the same, resulting in poles, like mapping onto a sphere. This way, though, leaves the circles entirely independent - it's mapping onto the surface of a Clifford torus, although .. er  .. I'm not sure it helps to know that.)
Tiling in Space
X and Y map to XYZW as shown below.. (the XYZW order doesn't actually matter, any old circles will do). The little division into 2*pi is just to get the tiling period to be logical in Blender units

Looping in Time
You can get the noise to loop in time by getting the centers of the circles we created before to go around another circle themselves, taking care not just to do it in X and Y, otherwise the texture would just go round and round in the tile:

Time Period is the repeat interval, Time Amplitude is the amount of shift per frame, and Time is the input that would be driven by some function of the frame number. The result is added to the previously generated XYZW.
With another node to scale the texture in the tiles, this is the tree:

An example of the result, tiled in space and time:

A node group with the described interface is included in the .blend:


The software is 100% free

here is a list of supported video formats

https://www.blender.org/manual/data_system/files/video_formats.html

But as far as motion tracking it depends if the camera is moving or not.

If the camera is moving, you can find out how it was moved by tracking things in the scene that dont move.

But if the camera is stationary, and you simply want to track a moving target.
Then you can do some simple math by finding out at what frame rate the video was recorded,
then checking how much the particle moved over how many frames.


Bevel modifier stops to work for diagonal faces

Welcome to Blender Stack Exchange!

There are a couple of things to try here.

First, select everything in edit mode and press ShiftN to recalculate the normals. Sometimes Blender gets the direction the vertices are facing confused, and this causes issue with beveling.

Second, try and get rid of the 'ngons', aka faces with more than 4 vertices. Beveling ngons is always a bit risky, and when you start moving things around it's not uncommon to see issues pop up. Insetting the ngons with I is a possible way to get some nice quads along the edge of your bevel.


Node Wrangler -- 'ShaderNodeBsdfPrincipled' AttributeError

I had the same problem. Try selecting the Principled BSDF node before trying to import your materials, that fixed it for me


Is there an easy way to make volumetric clouds for Cycles?

Let's use the Cloud Generator addon to make nice clouds and the new Point Density Texture to render them inside Cycles!

First enable the addon in User Preferences under Object: Cloud Generator.
Switch to Blender Render (the addon does not work under Cycles), add some cubes and turn them into clouds with the addon (the UI is located inside Tool Shelf T under Create > CloudGenerator in Object Mode):

(we won't use the explosion because it's not a cloud and requires a different Cycles shader)

After you choose the cloud type it will generate objects like this:

We are interested in the CloudBounds object and in CloudPoints.
Switch to Cycles Render and if using pre-2.77 Blender version use CPU rendering (Point Density does work on GPU in 2.77+). We need to give the CloudBounds object a Cycles material:

Play with the Radius and Multiply Node to fine tune the shape and density.

Delete all the non-used objects from the scene and make sure there are no Blender Internal materials left. All the CloudBounds should have Cycles materials and all the CloudPoints should be without material and hidden from render.
Add some lighting: Sun Lamp, Hemi Lights. Render:

When you get the hang of it create any shapes you like from differently sized and deformed cubes or some basic geometry.


Make an object a mask (render as transparency)

You can achieve this using a holdout shader, just don't forget to enable transparency in your render settings:


How to make glowing particles, with a solid glowing center

3 Concentric Spheres with Emission Particles

Blur in Compositor

Render result and 3 Concentric Spheres each with a particle system.  Image above.

Click on images to see larger view.

Compositor with Blur and Alpha Over Nodes. Image Above.

Particle Settings. 3 Panel of which 2 are pinned.  Unpinned is the largest sphere particle system.  Image above.

The 3 Object particles and the material settings. 2 are pinned.

Please experiment to your taste and improve.
Consider using a more irregular sphere in the center.
You may look at the movement of particle system on many frames and choose some particular frame.

Sloppy Imitation which may serve as a starting point.
Of course there are alternative and more CPU intensive ways to do this.


Alright so I came to a solution but it's not exact. This is more of a, "Soft" fix. In other words it's more of a workaround rather than an actual solution. I explain my findings in complete detail in this video I made for it:

https://www.youtube.com/watch?v=wW3u6qJk2TQ

For those who cannot watch the video, basically both the Neck Bone and Chest Bone as mentioned in the main post are currently connected via parents. By removing the parent-child relationship from the Neck bone of the Chest bone, the problem of the Neck Bone sharing the weights goes away.

Again this is not really an absolute solution but it works for now. I can make this a workaround by parenting the two bones via, "Offset" however making them parented via, "Connected" causes the issues of the weights.

If anyone still knows anything about this a solution is very appreciated. For now this is just a soft-fix. Thanks for all the support!


What is the best way to model the intersection of multiple hard-surface pieces?

If you're talking about cutting panels, There's a very nice non-destructive method demonstrated by Penfinity, at the time of writing, in two videos, here and with an improvement thanks to Nahuel Belich, here.

Penfinity likes to be a bit of a magician, so this answer will try to slow the explanation down a bit; draw back the curtain.

1. Select the Edges

..you would like to cut between the panels, and..

2. Assign them to a Vertex Group.

(the second halves of the following illustrations show the vertex weights, under the bonnet. You won't see most of that stuff, unless you apply the modifiers, and you don't want to do that..)

3. Assign a Bevel modifier

..with two segments, by 'Vertex Group'. This will isolate the edge selection from Masking later on, and determine the width of the gaps you are going to make. The modifier-created edges have an interpolated weight, which allows us to select them away in the next step.

4. Assign a Vertex Weight Edit modifier

..with the Vertex Group as its target. It is set to remove vertices from the group, with a full weight of 1 as the upper threshold. This results in the group being modified as shown:

5. Assign a Mask modifier

.. with the inverse of the modified vertex group as its target. This cuts a gap as wide as the original bevel into your mesh.

Now you can set where and how wide the gaps are, by adding/removing from the original edge selection, and setting the width of the first bevel.

This is the modifier stack at this stage:

Now you can add a Solidify, Bevel (by 'Angle'), and Subsurface modifier. Simply changing the settings in the first and second bevels can give you a lot of flexibility in the outcome:

and everything is editable.


How to subdivide a triangle fan (with some of the tris being ngons)?

The easiest way would probably be to Vertex Bevel (Ctrl+Shift+B) the middle vertex.


Environment behind window for interior renderings

If i understood you right (correct me if i am wrong) you do not want to see the HDRI through the windows, but just use the lights of it, right?
you can do that so: just tap on transparent


Vertex coordinates of mesh imported from Blender as fbx are all equal to 0,0,0?

I had this issue and solved it by unchecking the Scale Import option.  I think its because the model was too small so when it scales it down, everything is too close to 0.0 and gets rounded.
I imagine you were getting the same thing as most of your values are already 0.1 and then scale it down 100x it becomes 0.0.


How to set visibility on view layers via python?

FWIW, it's obj.hide_set(True), has been introduces 2 months ago or so, I think.


That would depend on the codec you choose to encode.

As an extremely simplified explanation:

When you render an image, Blender generates the information for Red Green and Blue and Alpha in 32bit float. Which is a lot of information. That image is not compressed in any way and all color information is available before processing to be encoded and saved.

Why not save then all of that information?

Not only it would take a lot of disk space, but you would need an extremely powerful device to play that amount of information in real time and sustain uninterrupted video streaming.

Compression schemes or codecs were invented to deal with the problem. Codecs allow for smaller files and facilitate playback at a steady framerate.

The efficiency and quality of the pictures is then determined by the codec used in the compression. Compression means that some information has to be thrown out.

In other words: when you choose a codec, you are choosing a way to discard information from an image.

One of the many ways is by using less information on the red and blue channels of the image than the green channel.

From the Wikipedia:

  Chroma subsampling is the practice of encoding images by implementing less resolution for chroma information than for luma information, taking advantage of the human visual system's lower acuity for color differences than for luminance.

Different codecs use different ways to do chroma subsampling

For example, ProRes can have many flavors: 422, or 4444. ProRes422-variants use Chroma subsampling of 4:2:2 at 10 Bit Color depth. ProRes 4444 samples color in the 4:4:4 schema with a color depth of 12 Bit. Most DnxHD codecs use 422 but the ones with the higher bit depth will use 444. Different variants of Mpeg4 or H.265 will use 422 or 444.


Is there a way to get the current rendering frame number?

Whats not really clear is how you mean 'get', since Blender isn't actively responding to events for example. Nevertheless, there are ways to do this.

Use the "Placeholder" render option

This writes an empty file, before rendering starts, other tools can check for these files to see which file is currently rendering.

With users and file ownership, its possible to check the file owner to see which system created the file.

Of course its possible Blender is interrupted, so, you may end up needing some supervision scripts to ensure the state is clean before starting.

Use Python "Handlers"

Blender has events you can subscribe to using bpy.app.handlers.
This is a catch-all since Python is very flexible.

In this case I think you would want the render_pre handler, which you can run when immediately before rendering.

eg:

import bpy
from bpy.app.handlers import persistent

@persistent
def render_handler(scene):
    filepath_to_render = scene.render.frame_path()
    print("Render Handler:", bpy.data.filepath, filepath_to_render)

    # access a file, log information over the network... whatever :)

bpy.app.handlers.render_pre.append(render_handler)

Inspect Blender's Output

Blender prints render information to the stdout,

You can log this to a file, and inspect the file for lines formatted as follows:

Fra:1 Mem:15.47M (0.00M, Peak 15.47M) | Time:00:00.00 | Preparing Scene data
Fra:1 Mem:15.47M (0.00M, Peak 19.87M) | Time:00:00.14 | Sce: Scene Ve:8 Fa:6 La:0

Even though this isn't 100% fool proof (its possible some Python script prints Fra:123), its easy enough to make a regular expression to parse the frame with reasonable certainty that its not mistaking output from elsewhere.

This is a simple example of a script that extracts the frame from a log-file, eg:

#!/usr/bin/env python3

"""
Get the current rendering frame from Blender's text output, eg:

python3 frame_from_log.py /path/to/file.log
"""

import sys
LOGFILE = sys.argv[-1]

frame = None
with open(LOGFILE, 'rb') as f:
    lines = f.readlines()
for l in reversed(lines):
    if l.startswith(b'Fra:'):
        frame = int(l[4:].split()[0])
        break
    elif l.startswith(b'Saved:'):
        # we're not currently rendering if it saved, early exit!
        break

if frame is not None:
    print("Frame found:", frame)
else:
    print("No frame found")

You may want to optimize it only to read the last lines of the file (for very long logs). but its a start.


Can I make fully transparent glass with no refractions?

Based on the image in your question, it doesn’t look like what’s causing the issue is refraction, but reflection. It’s hard to tell exactly why you’re getting so much reflection without more information about your specific materials and scene, but there are a few possibilities:

The normals on your glass pane could be pointing the wrong direction. Try recalculating them by selecting the faces in Edit Mode and pressing ShiftN.

The IOR on your material could be too high. The IOR of real glass should be about 1.5, but you could try lowering it closer to 1.0 to see if that looks better in your scene.

You might simply want less strong specular reflection than what the Principled BSDF provides. The Principled BSDF generally tries to be physically accurate, so deviating from it is likely to produce less technically realistic results, but you may want to do that, anyway, for artistic reasons.
In that case, you can manually combine a Refraction BSDF with a Glossy BSDF to get finer control over the amount of reflection:

By using a lower IOR for the Fresnel mix factor than you use for the Refraction BSDF, you can artificially lower the amount of reflection as low as you desire.


How can I get the location of all the objects in the scene at a desired keyframe using script?

the obj.location results in the local location, not including parenting relationships. Same goes for the rotation_euler.
loc = OBJ.matrix_world.translation
rot = OBJ.matrix_world.to_euler()
text_file.write('COORDINATES:', str(loc.x), ',', str(loc.y),',', str(loc.z) + '\n')

the matrix_world returns the actual world coordinates of the object after calculating all parenting and constraints.


Move the tracking point back to the correct position (manually) and continue tracking. If it looses track again, put it on the right track manually again.

If the video is blurry or jumpy the tracking can have problems. Rotating the camera fast will give you a blurry image.


Armature shifts between Pose mode and Edit mode

Summary

Make sure

Align origins of curves with Snap the first vertex position of curve.
you have not  repositioned the bones when you want to see standard rest position.

I believe you should either have

Separate Back spine concept and Separate Tail concept for Control concept. Fresh Start. Clear preference.
Switch direction of spine bones.  Less Preference.

The neck bones are reasonable.  The spine/tail bones are Blender Bites Ya.  Your current spine/tail is like the undesirable metaphor about the tail wagging the dog.  Note that I do not want address unrelated topics if possible, but this issue appears large.

Make sure you have not moved any bones in pose mode for the particular frame.    The point of pose mode is to place bones in different positions.

You may need to use Menu ... Pose Clear Transforms Location.  You may need to delete any keyframes.

Use the setting

Chain Offset enabled in the Bone Constraint Panel.  This will maintain the position of the root of the first affected bone.  The first affected bone will be the bone further up the parent chain as determined by chain length.

Successful use of Spline Constraint. Image above.

Additionally
For Precise placement in a different manner be very aware of your origin on the curve.

Align origin to first point on curve. Snap is used for precision. Image above.

Curve origin should be first point on curve. Be precise with the use of [Snap].  Edit mode curve, Select first point, snap cursor to selected, object mode, Transform Origin to Cursor.

It seems seems you made an effort to align with eyeball which is semi precise.  Snap is 100% precise.


Putting transparent image on curved surface with specific placement (UV)

You have to go to your node set up of your material for your blimp and add a Mix RGB node in which you will plug your transparent texture in the bottom color and the alpha of your texture to the factor of the Mix RGB node. Your color for the whole blimp should go to the upper color, finally you plug the Mix RGB node to your Diffuse node and then to your Material Output/Surface. *Don't Forget to unwrap the part of the blimp you want your transparent texture to be assigned.

p.s. if you want to have textures insted of colors you will have to create a second UV map, *don't forget to give your texture node the right UV map.

For more information I can recommend you this tutorial: *the blender version is quite old but the process is the same:
https://www.youtube.com/watch?v=dnmovLzKU44


Weird Ripples on Shape While Using Fluids

"Ripples" comes from domain grid resolution. Higher value makes them less visible. To spent less time by baking you can try Smooth modifier after Fluid modifier.

Note: As far as fitting everything in the domain, you can make the domain as big as you like, but just leave it box style in shape. The size of the domain does affect calculation time that is why it is best to crop it as close as you need to the fluid object participants.

blender 2.81a

use a Cube (rectangle) as a domain (not Sphere shape)
example with Final Resolution 120
Bake > Boundary > Surface Smoothing 2
Smooth modifier > Facor 2,5 / Repeat 12 (see second GIF)

Resolution 120 (even with smooth "ripples" are still visible)

Resolution 120 + Smooth modifier

In some cases you can "smooth" it by Boolean modifier - cut it out by a bit Smaller obtacle (heart), but its a dirty way (with many artefacts in shading and animation).

Just if you have an option I would recommend Flip Fluid addon (try Free version first). Without any additional setup just grid res 120 as well. Faster, higher res, preview calculated frames due baking ...

Resolution 65

Resolution 120

Note: Lines on Blender's fliud are the same as yours = domain grid artefacts. Lines on FlipFluid object is obtacle shape, it just copied surface so well. I should make it more smooth before baking.

blender 2.82

This version use MantaFlow solver you can try luck with it.


Keyframe a driver / Triggering scripted expression with a keyframe

You can use Python's ternary if-else operator:

function_of(y_location) if frame >= 32 else 0

You can nest these.

If you need to evaluate some object's position at given frame, you have to use PyDriver.

Like batFINGER suggested, binding this to the start and end position of the teeth rack (or to 2 empties) would work well also. That would look like this:

(rot_fce(y_loc) if y_loc < end_loc else rot_fce(end_loc)) if y_loc >= start_loc else 0


What's the most efficient way to draw edges for an object?

A possible way to do this is to use the Wireframe modifier. To get the result you want, add 2 materials to your object (the first for the faces and the second for the wire edges). Set the Pass Index of the second material to 1 (or any other number different from 0, which is the default value for any new material):

Add the Wireframe modifier to your object, and make sure to unchek Replace Original and to set the correct material index in the Material Offset input:

The final render will be something like this:


Why have objects moved from their original positions when I reopen my Blender file and how do I fix it?

If the objects were keyframed and then moved without setting keyframes once more, the information was not saved with the file and is lost.
You should manually realign the objects this time and in the future if you have animated objects in a similar situation where you don't want the animation, you should select them all, hit F3 and search for Remove Animation function:


The surface is uneven, because the vertices are arranged in such a way, that the faces are bent.
You can fix this by manually adjusting all the vertices to create the cleanest shape possible.

With the Subsurf Modifier enabled, you can barely spot the problem even with wireframes.
The uneven vertices are hard to spot.

Without Subsurf, the mistakes are visible. (Note that my example is very exaggerated, but the random offset of the five vertices is still not much.)

You can try and clean up your mesh, by going through all the vertices, and adjusting them manually from each angle. This can take more than one pass.

It will be easier if you use cleaner topology. When modeling with quads, it is advisable to make the faces as even and as square as possible.

In your mesh the faces resemble rectangles. Hence a just a slight variation of the vertices of the edge loop will make the surface seem distorted.

Try to have all edges similiar lengths, when modeling a single bent surface. (Of course once you want sharp angles, ridges, etc. this won't apply.)

You can achieve more even quads, by deleting some existing edge loops, which aren't necessary for the shape and add edge loops perpendicular to the previous.

With Subdivided Surfaces, you only need four vertices for a cirle. Keep topology rich in information, low in detail.


PBR Textures; can I mix them with basic MS.Paint images?

There are a couple of ways you can mix them. The way I would suggest is to keep your PBR material setup connected to the Principled BSDF, and then run your MSPAINT image through a Diffuse BSDF and mix the two using a Mix Shader.

As you can see from the image, I mixed them using a converted Black and White version of the original image as a mix factor. This is in the case you don't have a mask for your MSPAINT image (if needed), you can create one using a RGB to BW node and a ColorRamp.

Another way you can do this (which is handy if you only want to mix BaseColors, but have the rest of the PBR properties "apply" to your mixed image) is to mix the BaseColor texture of your PBR set with your MSPAINT image (using the same mix factor methodd, if desired) using a MixRGB node:


How to make this colorful shiny bubble in blender2.8? (iridescence)

You could use a shader like this. I find it works best with the Blend Mode set to "Alpha Hashed" (highlighted). I also found equally pleasing, but different results by using different inputs for the ColorRamp Leading to the Emission. The ones I found to work best are Position, Normal, Tangent, True Normal, and Reflection (also highlighted). Make sure bloom is enabled for the full effect. Make sure to rotate around the sphere as well, as the colors change based on position.
If you're wondering, the Noise Texture I used as a displacement is just to give it a bit of a "warped bubble" look to make it look more natural and to show off the colors better.


Can I move my position in video editor in 2.8 by clicking a mouse button anywhere?

Try Shift + Right Click will move the playhead to that frame.

For changing preferences: How to map "CHANGE FRAME" to mouse right click in Blender 2.80 in the VSE


this thread could help you: https://www.reddit.com/r/Unity3D/comments/ji7ok9/blender_grease_pencil/
I haven't had time to try it out yet, but it seems a proper way.
There is also this:
https://github.com/PierreMervaillie/GreasePencilToUnity


You just need to reset the object rotation values for the nurbs curve so that it is exactly 90 degrees on the X and Z axis. Then it will line up correctly.


How do i have my fire simulation have a better framerate/ quality?

Depending on your GPU, the frame rate in the viewport will reduce when previewing a fire/smoke simulation.  To make the fire look better, you could turn on “noise” and increase the number by the render label but remember to keep the number in power of 2, that usually works for me


Object turns black when selecting the new image to which texture will get baked to in Blender Internal

If you Shift+ Z You will switch to "rendered shading mode" instead of "material shading mode" and will see the texture.

After you bake it, it should be viewable in material shading mode.

Your texture wasnt attached to the file, so I found a random one online


The following should work with Blender 2.7x.

import bpy

def AssembleOverride(atype, rtype):
    for oWindow in bpy.context.window_manager.windows:
        oScreen = oWindow.screen
        for oArea in oScreen.areas:
            if oArea.type == atype:
                for oRegion in oArea.regions:
                    if oRegion.type == rtype:
                        oContextOverride = {
                                'window': oWindow,
                                'screen': oScreen,
                                'area': oArea,
                                'region': oRegion,
                                'scene': bpy.context.scene,
                                'edit_object': bpy.context.edit_object,
                                'active_object': bpy.context.active_object,
                                'selected_objects': bpy.context.selected_objects
                                }
                        print("-AssembleOverride() created override context: ", oContextOverride)
                        return oContextOverride
    raise Exception("ERROR: AssembleOverride()")
# ['EMPTY', 'VIEW_3D', 'TIMELINE', 'GRAPH_EDITOR', 'DOPESHEET_EDITOR',
# 'NLA_EDITOR', 'IMAGE_EDITOR', 'CLIP_EDITOR', 'SEQUENCE_EDITOR',
# 'NODE_EDITOR', 'TEXT_EDITOR', 'LOGIC_EDITOR', 'PROPERTIES', 'OUTLINER',
# 'USER_PREFERENCES', 'INFO', 'FILE_BROWSER', 'CONSOLE']
atype = 'OUTLINER'
# ['WINDOW', 'HEADER', 'CHANNELS', 'TEMPORARY', 'UI', 'TOOLS',
# 'TOOL_PROPS', 'PREVIEW']
rtype = 'WINDOW'

override = AssembleOverride(atype, rtype)
# old_id and  new_id must be pre-existing or operator will fail
bpy.ops.outliner.id_remap(
        override,
        id_type='MATERIAL',
        old_id='Material.002',
        new_id='Material.001'
        )


Is this it?
2 Attribute Vector Math nodes, and 1 temporary attribute to hold the offset.

'Scale' along normals might (strictly) be a misnomer... Solidify,  Displace, and AltS all translate vertices along normals.


Rendered image is not as detailed as in rendered view

It is from your subserf modifier. If your using the experimental or adaptive, make sure both values from the view and render are the same, i.e. the Dicing Rate must be 1 and the levels must be proportional to it.

And also the view angel will affect your render in adaptive subserf. Objects at the far will have less subdivision than those from the front, i.e, if your camera is pointing at the front and you are looking at the back, there will be a noticeable difference.


Blender 2.83, Cycles, can't get pointiness to work

As mentioned in the comments, on a cube with no curvature,or any type of bevel, you will see no result from  the pointiness output of the geometry node.
Pointiness as defined in the manual:

An approximation of the curvature of the mesh per vertex. Lighter values indicate convex angles, darker values indicate concave angles. It allows you to do effects like dirt maps and wear-off effects.

You can see this clearly in the following example:
All objects have the same basic node setup including the default cube on the left.

Click to enlarge
The node seteup used:


Despite the fact that the hand is completely red, it is still most likely a weight painting issue.

A vertex on a mesh can be assigned to multiple different vertex groups which means it can be affected by multiple different bones. Since the hand mesh looks to be moving about half as much as it should, I think you have the vertices assigned to a second group as well.

You can manually select the bones in weight paint mode to see which one is causing the issue, but there is a quick way to solve this without even knowing which bone is the culprit.

In the vertex groups panel of the Object Data tab of the properties panel there is a small, dark arrow pointing down located on the right side (under the Plus and Minus icons). With your hand vertices selected, click on it to open a menu, and choose the Remove from All Groups option.

This will remove any and all vertex groups from these vertices. Then select the hand vertex group  and assign a weight of 1 to your hand vertices and you should be good to go.


how to create realistic/physically accurate sand blowing over dunes animation?

Something can be done with Smoke simulation, partly used to fake soft dust and partly to be used as a Force Field > Fluid Flow for Particle system (sand particles).

Issue
The main issue with smoke sim is you can't expect backflip turbulences behind the tip of dune.

Note: to see smoke like this enable
Simulation Properties > Fluid > Viewport Display > Slice and Grid Display ... just move White slider to the left side of Colorramp to make it brighter.

version Smoke
I'm not going to do step by step answer since I don't know if this is a way for you. Just a quick overview ... One Landscape object is used to be rendered and also be Fluid > Effector for simulation (to let smoke flow over). Second Landscape (copy of first one) is used as Inflow object (emitter of smoke).
To build sim quicker ... with this object selected search for Quick Smoke. This operator automatically assign this object to be in sim Inflow object and creates also Domain with Smoke (volumetric) material.
The only one parametr I changed (probably :)) for Domain setting is Gass > Heat to zero (or something low) so smoke is not raising up, but stay on ground level.
Because we don't want to emit smoke from all surface, switch to Weight Paint mode and paint by Strength 1 (red) places you want to emit smoke. This creates a Vertex Group. Use this Group in Simulation Properties > Fluid > Settings > Vertex Group (usually named "Group".
Last thing ... add Force Field object type Wind here Strength 150, but probably can be less ... play with the value.

But if you need only to let fly some "dust" from dune edge, you can probably fake it by creating a Vertex Group only from top edge vertices and use them as smoke Inflow.
Enable for Domain under Physics Properties > Fluid > Dissolve for effect from your reference image.


Can I Replace Numpy with a Different Build?

I don't think it's used by Blender itself. Possibly certain add-ons do, though. You'll notice soon enough if something doesn't work any more ;-)
I think that's a pretty good way to go about it. It's not destructive, so you can always go back to the shipped numpy.


Photogrammetry using blender to Create a Dense Mesh and automatically texture them

As others stated on the comments Blender is not the tool to create cloud points from images.

I doubt there is any free, paid or open source photogrammetry tool that works on a 32 bit OS. Photogrammetry would require a more powerful platform, as it  will generate huge amounts of information to create what you call "a dense mesh cloud". A 32bit machine can only deal with 4GB of memory (and that includes the Operating system,that will take at least one GB, leaving you with only 3GB of ram to work with). But even if by some miracle hack you would be able to generate generate objects on such platform, you will hit the limits of the hardware before you can manipulate any of that information.

3D modeling and rendering can be very demanding for any computer, a common mistake folks make is to creating projects that are more ambitious than the resources available to them.

Think of an alternative, more realistic or down to earth way to create what you want within your available means.


Select random faces but no adjacent faces

Another bmesh script

Similarly to @gorgeous
import bpy
import bmesh
from random import choice

context = bpy.context
ob = context.object
me = ob.data
bm = bmesh.from_edit_mesh(me)

ratio = 0.5
for f in bm.faces:
    f.select_set(False)

faces = set(bm.faces)
chosen = 0

while faces and (chosen / len(bm.faces)) < ratio:
    face = choice(list(faces))
    face.select_set(True)
    faces -= set(f for v in face.verts for f in v.link_faces)
    chosen += 1

bmesh.update_edit_mesh(me)


Simple driver

For constant rotation of a sphere / circle

Think I used a poor choice of frame rate for gif

The distance a rolling circle travels is radius * angle  with angle in radians.
Circumference is special case of arc length. Gives the distance traveled for one full revolution, or 360 degrees or 2 * pi radians.

The angle theta rolled for a distance d

theta = d / radius

Set up a simple driver on the y rotation of a sphere based on its x location, and half a dimension as radius.  Using self on drivers rather than a more traditional driver variable approach (Which removes warning)

Drivers Editior

Properties panel

2 * self.location.x /  self.dimensions.x

any dimension (diameter) could be used, or hardcoded

Using this our ball rolls about y as it travels along x.

To change the direction, possibly the simplest is to parent the whole setup to an empty.  Or use angle axis rotation


Animated texture that depends on camera perspective

Using WINDOW TEXTURE COORDINATE
Use a Window texture coordinate for mapping. Adjust Location, Rotation and Scale parameters of the Mapping node to make the texture fit the object borders.

Using UV PROJECT MODIFIER
Subdivide your cube a few times and unwrap it (I've marked seams and then unwrapped).

Add the UV Project Modifier. Set up your image texture, set the Camera as a projector. If the image doesn't display correctly adjust the Aspect values.


How can I change default file save locations?

Head over to your User preferences here :

Extra Tips:
Or you could typically move the windows folder with "mklink" using windows
command prompt. Search google for makelink windows tutorial and you be really
powerful at managing your memory resources.


Volumetrics behind glass arent working in Cycles

I'm not sure what you mean by "the volume is not visible": is it black or is it just as if it wasn't there? (A screenshot would help)

If the problem happens only from behind a transparent surface, you may have the "Max Bounces" settings too low in Render > Light Paths


Does decimate modifier decrease render time or memory usage?

Principally, the decimate modifier reduces face count. A smaller geometry leads to less memory usage and a shorter render time.

BUT: The modifier is slow. Really slow (Don't blame it, reducing geometry isn't a simple task). Before rendering, all modifiers are "applied" so that they can get rendered in the "Syncronizing object" phase as Jerryno said. This will add some overhead to your rendering time.

If you can afford it, apply the modifier. Then it will calculate once and for all instead of at every render. Eventually back up your object somewhere else just to be sure.

Also please keep in mind that the decimate modifier is a "I messed up the polygon count" quick fix. If you need it, in most of the cases that's a hint that you made a mistake somewhere. See here for alternative solutions.


⎈ CtrlR  to add a loop cut.
G, G to edge slide.
G to move/grab.
G, Y to move along global Y axis.
⎇ Alt RMB to select an edge loop.
E to extrude.
⎈ Ctrl↹ Tab to switch the selection context.
B MMB to box deselect.

Double Geometry  (not that good)

Add two loop cuts. Edge Slide the lower loop cuts upwards. Deselect the back vertices and select the lower ones. Move them back along Y.

N-Gon  (not that good)

Delete the side faces, add two loopcuts and move the vertices together. Move the lower face along Y. Make the missing face F.

Extrusion

Add one loop cut. Select the upper face. Extrude the upper face.
Multiple meshes

Duplicate the geometry, move and scale it accordingly.

  Now, although you probably had #3 in mind, I'd advise you to think about the benefits of #4. In the real world, these object would be two separate pieces as well, with separate materials.


Processing when ModalOperator has already been executed

This can be solved by checking whether the timer has been set before. Unfortunately the example has a little confusing mistake. self._timer = wm.event_timer_add(0.1, window=context.window) does not assign a value to the class attribute _timer as declared at the beginning of the class. Instead it creates an instance attribute named _timer. You can see this by adding the following two lines after the assignment:

print(f"self._timer = {self._timer}")
print(f"ModalTimerOperator._timer = {ModalTimerOperator._timer}")

The first print() will show the the content of the instance attribute, the second print() the content of the class attribute. If you try this you will see that the class attribute will always be None, it's never assigned the value. Therefore this needs to be fixed before you add the check to see if a timer has been previously assigned.

One way of solving this, is making all reads and writes happen to the class attribute by replacing self with ModalTimerOperator and thereby actually using the class attribute declared at the beginning. Then you can check in execute whether the timer is None and only then add a new timer when it is. Set timer to None when the modal operator is canceled.

Update: In order to follow the naming convention I've renamed ModalTimerOperator to WM_OT_modal_timer_operator.

import bpy

class WM_OT_modal_timer_operator(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):
        if event.type in {'RIGHTMOUSE', 'ESC'}:
            self.cancel(context)
            return {'CANCELLED'}

        if event.type == 'TIMER':
            # change theme color, silly!
            color = context.preferences.themes[0].view_3d.space.gradients.high_gradient
            color.s = 1.0
            color.h += 0.01

        return {'PASS_THROUGH'}

    def execute(self, context):
        wm = context.window_manager
        if WM_OT_modal_timer_operator.timer is None:
            WM_OT_modal_timer_operator.timer = wm.event_timer_add(0.1, window=context.window)
            wm.modal_handler_add(self)
            print("Adding new timer")
        return {'RUNNING_MODAL'}

    def cancel(self, context):
        wm = context.window_manager
        wm.event_timer_remove(self.timer)
        WM_OT_modal_timer_operator.timer = None

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

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

if __name__ == "__main__":
    register()

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

If you register the operator and then run it multiple times through F3 or Edit > Operator Search, you will see that a new timer is only added when there hasn't been a previous one or it has been canceled.


How to add physics to the object that already follows another object?

The ideal physics for your lamps is probably rigid body physics.  It is possible to combine these with soft body/cloth physics, but the philosophies and techniques are different.
In order to anchor these lights as rigid bodies to the line, you'll first have to make an "anchor" body to hold them there.  Create a cube (or any solid mesh, doesn't matter) at the point where they hang from the line, give it rigid body physics, and then check the "animated" trait in properties/physics/rigid body/settings.  "Animated" means it's under your control, so, you'll need to do something to make it move with the cloth physics mesh.  One way to do this is via vertex parenting (I parented it vertex triangle to three points in a cloth strip), but if you'd rather, your technique of copying location from vertex groups is fine as well.
Disable rendering on these anchor bodies.  I set mine to display as only wireframe as well.
Next, you can give the lamps themselves rigid body physics.  Default settings are fine, although you'll want to make sure that the origins of the objects lie somewhere near the middle of their volume (the origin is the center of mass.)  Remove any constraints or parenting from these objects if you have any.
Next, you'll need constraints so that your lamps stay attached to the anchors.  For each anchor body, create an empty at its location, then give the empty Rigid Body Constraint physics.  Set these to "point" type instead of the default "fixed".  Then, in the Objects subsection, specify your anchor object as the first body and your lamp object as the second body.  These empties should remain unparented and unconstrained; their positions won't make any sense during your animation, because it's their relative orientation at your first physics frame that determines how they work.  (As point constraints, they're going to try to keep your lamps on a spherical shell around the anchor, and exert physics forces as needed to do that.)
Here's it after a few frames, with some pinned windows to demonstrate physics settings:

Note: what's happening here is that Blender is running your cloth physics, and only afterwards, running your rigid body physics using the positions provided from the cloth physics.  Don't imagine that the hanging lamps will exert force back on the cloth; it doesn't work that way.


Mesh has invisible parts after exporting

It looks like:

The human mesh's normals are flipped. You can correct that by selecting all of it in edit mode (A) and then pressing CtrlN
The hood/robe mesh has no thickness, so parts of it will disappear due to backface culling. You can fix this by adding some thickness with the Solidify modifier.


Your environment lighting (world and light) was very bright. So first thing, change your lighting. Also, your coffee material has a Transmission of 1, which makes it reflect the environment like a glass, and a Roughness of 0.55, which makes the reflection scattered all over the surface, it's not what you expect from water, and it creates a rather grey material, you can't see the Volume Absorption effect any more.

If you don't want this scattering effect, which would make more sense, low down the Roughness value:

You can also mix your BSDF with a Transparent node to lown down the glass effect:


Forces only have an effect on rigid bodies on the same Layer - so use separate layers for each set of independent objects and forces.

Essentially you need to do the following :

On one layer, create objects A and B. Create a 'Force' force field at the origin of object A (select object A, press Shift-S and select 'Cursor to Selected', then Add/Force Field/Force) and parent it to object A. Create a 'Force' force field at the origin of object B and parent it to object B. Set each of the force fields to a negative strength (eg, -50). You should now find that A and B are drawn towards each other.

Swap to the next layer and repeat for C and D.

Running the animation (with both layers selected) should now result in two pairs of objects attracted to each other but not the other pair.


When you save a file, it actually adds to the amount of memory being used in Blender currently. This happens to me quite often. When this gets bad enough, I usually save the file a last time, and then open the Blender file again. When I re-open the file, the previous saves' memory and history is not accounted for, and saving again is very quick.


How can I make different textures on the same object?

You can do this all using only one mesh and procedural materials, even using the blender internal render.

Add a material, then go to the texture tab of the properties window.
Add a new "Blend" texture.
Down in the "Blend" section, set the "Progression" to "Spherical".
Set the texture coordinates to "Generated".
(Now the fun part) Go back up to the "Color" section and check the checkbox for "Ramp". Set the interpolation to "Constant"
First make sure that you set the alpha of the first color stop to 1 (By default it is zero).

Now we are ready to add new color stops in the color ramp.
As shown in the image below you will need one stop placed at 0 (the far left) then two more color stops. These next two color stops make the ring.

Using two meshes
If you want to use two separate meshes (can be in the same object or separate objects), then you need nothing more then a simple material on each part.

Here I applied a purple material to a basic circle. In the same spot (just slightly higher)  I have a smaller circle. This circle I extruded E, then scaled S so that it is just a thin rim (green in the picture). I then applied a green material to this mesh.
If you have both of these pieces in the same object, then you will have to apply the material in edit mode as explained in this answer.


I set an background image but i can't actually see it all

In 2.79 background images have settings in the Properties shelf on the right of the 3d viewport. There is Opacity slider which by default is set to 0,5 (50%). Set it to higher value if you want the image to become less transparent.

See more about how to setup background images while in 2.79 How do I set a background image while I am editing?

Note that in 2.8 background images are used in another way


Is it possible to unwrap genus-0 mesh so each vert has one and only unique uv?

No.

Unwrap. Meaning peeling the surface off of a solid and laying it out flat on the ground.

If your requirement is that there are no duplicated texture coordinates at all, it would mean that you are trying to peel an orange without cutting its skin. Even if you manage to "beam off" the skin in one piece you end up with a hollow shell that you cannot lay out flat on the ground without the front and back sharing the same area.

And the moment you cut it you get seams and therefore more uvs than vertices. if you merge them again later you once more end up in the situation described above.

This is true for all solids, not just genus-0 ones like a sphere.


Blender Video Editing: How to create custom effect strip?

I don't know how to code an effect and I believe that it is a bit of a challenge. You could use python to code adding a transform effect with those parameters already defined, or you could append this metastrip plus effect fro another "master" blend file scene.

Here I have created a metastrip by adding a color effect (red) then pressing Ctrl-G. To this metastrip I added a transform effect and set the scale and x,y values. I also changed the blend type to "overdrop"

Next I selected the metastrip and its transform effect and duplicated them with Shift-D. I can place this duplicate metastrip anywhere on the timeline. Press the TAB key to step nside the metastrip and change the media.

Press the TAB key to get back out to the master sequence timeline, then you can drag the end handle of the metastrip to the correct new length.

Then you could split your screen to make a little FX bin on the side.

This is at timeline -0. In other words, you place a bunch of stuff outside the rendered timeline. Then you can select them no matter where you are in the edited timeline. They wont zoom or move unless you change it. I have also altered the color of that red strip in the other effect so that you can identify the one that you want to use, it may have different x,y offset values or scale etc.

Also you could enable the Addon Extra Sequencer Actions, then use it to copy the transform and blend type properties from your original effect to the others. It is a bit fiddly to select correctly. Make sure the master effect is the last one that you select.


Blender Crashing When Rendering Simple Scenes

This is a corrupt file on preferences. I´m sorry but you´re going to start blender anew afresh, asap. :)
go to: C:\Users\3DCompositor\AppData\Local\Blender\Cache
Delete everything you got in there.

Go to: C:\Users\3DCompositor\AppData\Roaming\Blender Foundation\Blender\2.79 or 2.8 whatever of the two folders you have there: delete it.

I´d assume you don´t have many new configurations or shortcuts. But even if you did, clearing out these locations will grant you a fresh copy of Blender.

Also go to: C:\tmp
And wipe out all traces of any myfile.blend you could have there.

START BLENDER and if you CAN´T and Blender still crashes, the second thing to check is a FAULTY ADDON. Do you remember having added an ADDON recently? IF so: Please uncheck it and delete it from Blender´s addon folders:
C:\Users\3DCompositor\AppData\Roaming\Blender Foundation\Blender\2.79\scripts\addons

Last but not least try to run blender after all of these operations with only 1 monitor (YES ONLY ONE AFTER CLEANING) for a regular 10 minute session. IF you don´t notice anything weird, proceed with the SECOND monitor (plug your monitors with your PC OFF!)
Work for 10 more minutes using BLENDER. If you didn´t have any crashes, Turn off PC, connect 3rd monitor, and work with Blender for 10 more minutes.

If Blender crashes while you render while you have monitor A, B, or C connected you´ll know which one could possible be malfunctioning.

All right, thank you if you vote me as the answer.

BFCT_Schiller


How to setup your system python for use with Blender

Edit.. If having encodings hassles try virtualenv
After installing python 3.77 to /usr/local/ from a tarball, thought I would  create a new python venv for blender.  Using /usr/local/bin/python3.7 -m venv foo --copies I ran into the no module named encodings error, and found no way to alleviate the situation.
Thought I'd give the somewhat deprecated virtualenv a try, and bingo, blender ran straight up.
/usr/bin/virtualenv -p /usr/local/bin/python3.7 --always-copy foo

creating a copy of the python to venv and from it blender runs without any extra steps required.

A way for Ubuntu
Having horrible issues building blender currently, so have gone thru the motions of setting up virtual environments for freshly downloaded 2.91.2 and 2.92.0
Have both in vers folder
Note commands shown below are <prompt> $ <command>
shitbox:~/blender/vers$ ls
blender-2.91.2-linux64  blender-2.92.0rc-linux64

renamed the python folder in both from python to _python
shitbox:~/blender/vers/blender-2.92.0rc-linux64/2.92$ mv python _python

Now set up a virtual environment named "bar" and changed into that directory
shitbox:~/blender$ ~/blender/vers/blender-2.92.0rc-linux64/2.92/_python/bin/python3.7m -m venv bar --copies
shitbox:~/blender$ cd bar

next have made link copies of blender's distribution python lib to venv lib
shitbox:~/blender/bar$ cp -as /home/batfinger/blender/vers/blender-2.92.0rc-linux64/2.92/_python/lib .

Created  symlink to blender into the venv's bin.
shitbox:~/blender/bar$ ln -s  /home/batfinger/blender/vers/blender-2.92.0rc-linux64/blender bin/blender

activate the venv
shitbox:~/blender/bar$ source bin/activate

and start blender telling it to use this venv
shitbox:~/blender/bar$ BLENDER_SYSTEM_PYTHON="$VIRTUAL_ENV" blender

The environment variable can be set in the activate script in your venv's bin folder, however on Ubuntu I am using direnv which automagically activates the environment when entering the folder using an .envrc file. So I have stuck it in there
export EDITOR=nvim
source $(pwd)/bin/activate
export BLENDER_SYSTEM_PYTHON="$VIRTUAL_ENV"

echo "Blender 2.92"

and similarly for 2.91 in "foo"
(foo) shitbox:~/blender/foo$ blender
Read prefs: /home/batfinger/.config/blender/2.91/config/userpref.blend
found bundled python: /home/batfinger/blender/foo

Can install in the venv with pip
pip install matplotlib

and bingo in blender
>>> import sys

>>> sys.executable
'/home/batfinger/blender/foo/bin/python3.7m'

>>> import matplotlib
>>> matplotlib
<module 'matplotlib' from '/home/batfinger/blender/foo/lib/python3.7/site-packages/matplotlib/__init__.py'>

Notes.
Above is demonstrating how to use the python that ships with blender to make a venv. Would be very inclined to download and build the matching version Python3.7.7 and use this as the basis for a venv. (It's my experience that python builds pretty well hassle free)
It's been a while since I downloaded an official build of blender and was a little surprised to see both versions above using python 3.7.7. (Have been building against 3.8.2 since blender 2.7, last run of install_deps.sh to build was using 3.9.1 .. miss not building with the "latest" .. don't miss when it doesn't work)
Since both venvs use same python version it feels a little overkill to install scipy, matplotlib, pynvim, plumbum and other 3rd party modules I use alot for each venv.
In the past any module  I wish to have available for all instances I have used
pip install pynvim --user

which is unavailable in venvs as setup above, unless python --system-site-packages was used creating venv, or in hindsight edit pyvenv.cfg to have include-system-site-packages = true
or add a   path to python path in .envrc with
export PYTHONPATH="$HOME/.local/lib/python3.7/site-packages"

will make that path available to python in your venv, but not in blender..
A quick way around this is make a script to add paths to blender
addpaths.py
import sys
sys.path.append("/home/batfinger/.local/lib/python3.7/site-packages")

and start blender with
blender -P addpaths.py

TODO write a script to automate the above.


Render light hitting an object, but not the object itself

Depending on whether or not you plan on simulating the materials of the subject, perhaps a setup like this would work:


How do you place a cut at a specific measurement?

You can use snap to attach the face to the wall edge:

Then use typing move to manage your door to the desired position:


The answer is simple. When creating the normal map, make certain your objects are smooth shaded. I don't remember any of the tutorials I saw stressing the importance of this fact, but if they aren't smooth shaded Blender will not automatically interpolate to smooth, and your normals will have abrupt changes at the grid lines.


Check your topology. You have N-gons and triangles. Stick to rectangles so the subdivision can work properly. Use MatCap's for a better view of lightning around the edges when adding new loop cuts so you dont have to go to modeling hell.

I have fixed your cube for you. I'm still using Blender 2.79 so you can import the fbx from here: https://drive.google.com/file/d/1_hVeMLHYu2jdWg9_t7FFv98-NyJLxZTO/view?usp=sharing


Insert keyframe through python and set its properties

Found a solution using this related thread https://blender.stackexchange.com/a/32540/31246 and this How do I add keyframes to a newly created action with no associated objects? (thanks @batFinger)
Here is the resulting code where i already have a bunch of variable (frame, value, data_path, array_index, handle_left_type) :
# parent is the object/node_tree ... containing the animation_data
# get_unique_name is(collection, base_name) is a function to ensure name is not used,
# and if so iterate by adding numbers

# find fcurve
if parent.animation_data is None:
    parent.animation_data_create()
a_d = parent.animation_data

if a_d.action is None:
    new_name = get_unique_name(bpy.data.actions, parent.name + "Action")
    a_d.action = bpy.data.actions.new(new_name)

fc = a_d.action.fcurves.find(data_path, index = array_index)
if fc is None:
    fc = a_d.action.fcurves.new(data_path, index = array_index, action_group = group_name)

new_key = fc.keyframe_points.insert(
        frame,
        value
        )
new_key.handle_left_type = old_handle_left_type

Cheers !


I've tried this, I think it needs more hair work though, to get the fluffy thing. For the material, I've used a Noise Texture that I've scaled on one axis to get the stria effect. Emission is here to give a bit of luminosity and softness to the object, too much shadow would make it look solid like a stone, it somehow simulates a transparent effect. And at the end a bit of Transparency, with a Fresnel as factor, to make the contour a bit evanescent. The hairs are actually long extruded rectangles with a material that also use a mix of Diffuse, Emission and Transparency.


How to deform individual particles along the same curve guide that they are all traveling on?

That can be done using Animation Nodes.

The principle is to make a duplicate instance of an object for each particle.

This base object is associated to a curve modifier.

The tricky thing is that you can not place the duplicates at the particle position, because this will not fit with the modifier (we need to follow the curve axis specified on the modifier, but stay constant on the other axis).

So, we keep the particle position for the modifier axis only (here Z) and for the other axis (here X, Y) we take a constant random position.

Last part: we want a vector of random fixed positions for each particle but the particle life cycle varies. So we consider all particles from the beginning and hide the died one at the end.

1: Get the particle system considering alive and died
2: Instantiate a copy of the base object for each of them
3: Take random positions for X and Y but keep the particle Z
4: Get the dead particles amount
5: Place the objects
6: Hide the dead


How do I smooth out two objects (with low poly) that have been unioned in blender 2.8?

You can join two spheres this way and adjust for your character as the process should be the same.

Create a sphere with 16 segments and 8 rings

Create a second sphere half the size

With the smaller sphere selected go into edit mode and line up the edge loop with the larger sphere. You can do this by eye

Add a boolean union to the large sphere and select the small sphere to join

Apply the boolean and shade smooth with a subdivision surface x2

To transform the body I would add a lattice with a vertex group on the base mesh to limit the lattice influence and this way you keep the head round

you can then transform the body shape as required


Flag Physics seems fine when on the viewport but looks messed up when rendered

Do you have any subdiv modifiers for that flag? If so make sure they have the same amount of subdiv steps on render and viewport. Because the gif you posted seems to have more geometry on it than the last image you posted...


Obstacle on path does not interact with fluid

In case anybody else will need this, Export Animated Mesh under Physics tab -> Fluid worked for me when applied to the obstacle. In Blender commented "only use if really necessary", but it worked. One disadvantage here - it is not possible to set the Slip Type.

Maybe I just missed some settings, but without that I couldn't make it work.

I also thought it may has something to do with the original position of the obstacle (before constrain to path added), which doesn't change, but this is just guess, not sure what is behind that in Blender's core.

This did lead me to the solution - Gimble answer

And here is the Blend file:


What you've done looks more like an altE > Extrude Individual Faces than an E (simple extrude). If you select the whole ring of faces, make a simple E, then S + shiftZ to scale on X and Y axis, you should get what you want.


You need to UV unwrap an object before an image texture will show up.

Here's a quick refresher on how it's done:

Select the object and hit TAB to enter edit mode
Change the selection mode to edges
Select all of your 'seam' edges
Hit Ctrl+E to bring up the edge menu and click 'Mark Seam'
Select all edges in the object by hitting 'A'
Hit 'U' to bring up the UV mapping menu
Select your unwrapping method. 'Unwrap' is the quickest

If your UV/Image editor window is open, you should be able to see the unwrapped object. From there you can mess with its position, rotation, and shape.

Hope this helps!


FFmpeg is not a format.
It is a suite of libraries and programs used to create files using different containers and codecs, used mostly for video files.

PNG is a file format in which you can save images.

Which one to use depends on your needs.

Usually when creating animations or video it is recommended to render as an image sequence and encode to video later. That way, if the render stops or fails, you don't lose all of your work and you can try a different encoding and format until you find the one that works for you.


I don't think you can remove frames. However, you can go into the "Animation" screen and move your keyframes closer together.

Go to the top of the window where it says "Default" and from the drop-down choose "Animation". You'll get a Dope-sheet on your left. You have to find your keyframe, select it and move it. Normal keys for selecting and moving, thus A for toggling selection, right-click for selecting, and G for moving.


The python console

In object mode, have added the default bezier curve object

The data part holds curve data

>>> cu = C.object.data

A curve is a set of splines, a spline a set of points to define its shape.  Investigate spline 0

>>> spline = cu.splines[0]

Can auto complete in py console, eg pressing TAB Autocomplete key may differ see console menu or start message

>>> spline.r<tab>
            adius_interpolation
            esolution_u
            esolution_v
            na_type

Hmm radius interpolation, expect a radius property to be on the points, have 2 points

>>> for pt in spline.bezier_points:
...     pt
...
bpy.data.curves['BezierCurve'].splines[0].bezier_points[0]
bpy.data.curves['BezierCurve'].splines[0].bezier_points[1]

whats the radius of the last

>>> pt.radius
1.0

set to 19

>>> pt.radius = 19
>>> pt.radius
19.0


First of all, I can really recommend mikeycalmeyers videos on youtube. He has a whole series exlaining how to do video editing with Blender.

To answer your question, there are multiple ways to trim:

Option 1) Select your video and audio by holding shift and right clicking on them. Then put the green marker at the moment in time where you want to make a cut. From the menu just below your video sequence editor (the one with the tracks) choose Strip > Cut (soft) at frame, or press the shortcut key K. This will split it into separate parts, so you can delete the parts you want to remove.

Option 2) Select the arrows on the left side of both your video and audio tracks by holding down shift and right clicking them. Then you can move them by pressing G and moving your mouse. For precise control use your arrow keys. When you moved it to the right location press enter.

To speed up your video:
Select (only) your video track with a right click. Then go to the menu in the video sequence editor and choose Add > Effect strip > Speed Control. Then on the right side uncheck Stretch to input strip length, set speed factor to 1 and multiply speed to 5 (or any other speed you like). You will need to drag the arrow on the right side of your original video track (so not the speed control) to match the new duration of your video track. Changing the speed of audio does not work this way, so I would use Audacity to change the speed and then import it into Blender.


Making circular actions without inserting keyframes manually?

Method for a primarily 2D context.

 RMB select the foot bone and go into edit mode of the armature. ↹ Tab
Create a parent bone at the position, you wish to rotate the foot around. ⇧ ShiftA Bone.   RMB select the foot, then ⇧ Shift RMB select the parent, and parent them with an offset. ⎈ CtrlP > Keep Offset.

Select the child and in the Properties context, in the bone tab, in the Relations section, uncheck Inherit Rotation.

Go into Pose Mode ⎈ Ctrl↹ Tab. Select the parent, key the parent at a rotation of 0°, then at a rotation of 360° a few frame later. Locate the keys in the dopesheet and select them. Press ⇧ ShiftE > Make Cyclic, to make the rotation action loop. Press T > linear, to transform it into a linear motion.

Alternatively to the cyclic repetition, you could press ⇧ ShiftE > Linear Extrapolation.


How does the Vertex Weight Mix Modifier Work Internally

Have a slow read through the manual page on the vertex weight mix modifier, it has an example at the end to help explain it.

The points I think are most relevant -

  Vertex Group A
      The vertex group to affect.
  Default Weight A
      The default weight to assign to all vertices not in the given vertex group.
  Vertex Group B
      The second vertex group to mix into the affected one. Leave it empty if you only want to mix in a simple value.
  Default Weight B
      The default weight to assign to all vertices not in the given second vertex group.

  Mix Set
      Choose which vertices will be affected.
      All vertices
          Affects all vertices, disregarding the vertex groups content.
      Vertices from group A
          Affects only vertices belonging to the affected vertex group.
      Vertices from group B
          Affects only vertices belonging to the second vertex group.
      Vertices from one group
          Affects only vertices belonging to at least one of the vertex groups.
      Vertices from both groups
          Affects only vertices belonging to both vertex groups.

  Texture Mask
      An additional texture, the values of which will be multiplied with the global influence value for each vertex.

So Vertex Group A is the group that gets the result, you use this in modifiers after the mix.

The mix mode defines how the two values are mixed, while the set decides which vertices get the weight.

The texture mask can then limit the result to certain areas of the mesh.


I solved the problem by raising the samples count to 400


Object doesn't follow the navigation mesh path using steering actuator

Instead of setting a "Navigation Mesh" physics type on an existing object, you should generate the navigation mesh via the relevant button in the scene properties.

In my tests, that seems to work fine.

Here's a tutorial for that procedure: https://www.youtube.com/watch?v=aMWeTXL98mM

And here's a working demo: nav_mesh.blend


The issue is that .OBJ format by standard does not support vertex colors, so Blender isn't importing them. The way to append vertex color after vertex position is only a third-party hack to the format, and thus the support is limited in many applications.

Please follow this post about importing an .OBJ file with vertex colors into Blender and you should be able to see, render and bake the colors no problem.

How to display and use Vertex Color from OBJ model


How to texture a downloaded model made of stretched triangles?

This is caused by N-gons and double vertices.

If you only need simple shading, go Object > Shade flat and disable Autosmooth.

You can also use Mesh > Clean up > Limited dissolve to merge flat faces.
Before any larger changes, the mesh should be properly repaired.


Cannot combine results from different renderlayers?

Blender Internal:

The reason the sphere is black is because the lamps are only on layer 1, but not on the sphere layer.

You can move objects to more than one layer at once by pressing M and Shift clicking on the layers on which you want to make the selected object(s) visible.

Cycles:

Try enabling Transparent in Render settings > Film:


How to control the direction a bone rotates?

Experiencing this kind of rotation interpolation problems are not common in your case because you are using Quaternion Rotation. But similar problems can be found easily in the shoulder-like joints if you are using Gimbal rotation (any of the Euler XYZ combinations). Anyway, there is a similar approach for both cases.

First, you need to know what kind of rotation is being used. It's simple: under rotation axes you'll find Quaternion or Euler (in this case means Gimbal).

The common solution for both rotation types is adding one (or many) inbetween keyframe to "force" the rotation to go through your desired way (like @sambler told in the comments). If you are working with Quaternions, doing that is a must in big rotation changes.

Why does it happen? In Quaternion, the WXYZ axis are defining a point in a 4-dimensional sphere. For better understanding, we can imaging the same applied to a circle in this image:

So the rotation is actually a point traveling through a circle but not only through the edge. In your case, I think that your rotation was more than 180 degrees, so the interpolation went by "the other way" of the circle.

Note that the spacing of the rotation is not linear, so it's always recommended inserting inbetween keyframes specially in big rotations.

In Gimbal that's caused because of the gimbal lock. Gimbal axes are parented between themselves. So if you're working on a Euler XYZ setup, X is the child of Y, which is the child of Z. If you rotate 90 degrees the Y axis, then the X axis will align with the Z resulting that two axes are doing the same rotation and you have lost a rotation axis actually.

So there's another solution if you are working with Gimbal: Euler Filter. Euler Filter is located in the F-Curve Window in the Key Menu:

There is plenty of material in the Internet about Gimbal lock. If you want to know more about Quaternions or Gimbal in Blender, are pretty well covered in Nathan Vegdahl's Humane Rigging DVD (you can check Quaternions video here). Actually the two circle images are from that video (under a CC Licence).


I solved it!

I have the problem in shaders, used noise textures without connecting uv map:

Connecting like that:

Now its working perfectly!


How do I shift a vertex to establish a single, flat surface on a quad?

If you only care about planar faces in general, then there's an automatic way for that by selecting Mesh > Clean Up > Make Planar Faces.

If you really want to only move a specific vertex of the quad, you can

move the 3D Cursor to one of the three other vertices (Select the vertex, Shift+S > Cursor to Selected) and switch to Pivot Point > 3D Cursor (. key)
Shift-select all three vertices that should define your plane and should not move
Hit Ctrl+Alt+Space to define a custom Transform Orientation
Select the vertex that you want to move and scale it locally along the Z-axis of the new transform orientation: SZZ 0 Enter


Compute Device None is a bit misleading here – it just means, that there's no GPU available. The scene will be computed by your CPU. Your invisible smoke is quite another matter and should be handled in a separate question.


You've set the strength of the normal map node to 0 accidently.


Buttons for custom properties don't refresh when changed by other parts of the script

Ideally this would worth without any explicit update or redraw calls, however - this issue can be resolved by tagging the area for redraw.

After the assignment call context.area.tag_redraw().

Note that normally its best to use context.region.tag_redraw() (which would redraw only the panel), however its not working in this case because this region isn't active when the pop-up executes.

You could store the region before executing the operator, but this is probably more hassle then its worth.


Or Apply your Subdivision.

Until you hit "Apply", it's just a previz of the subdivision that you COULD get.

When rendering, it doesn't matter but the best practice would be to apply all your subdiv before final rendering...


These are two completely different versions of Blender.

You are using 2.79, the current stable official version, the tutorial you are following is for the upcoming 2.8 version, a major refactor of the application, currently in release candidate phase.

You can download both from the Build Bot, but have in mind that 2.8 is not ready yet and is not advised for production. While backwards compatible, both versions are also considerably different, so it is unadvised to switch between the two with the same project.


This could be a result by making the switch from 'GLSL' to 'Multitexture' shading.
Try switching your shading method.


The reason for this is that none were created, the author simply unwrapped the models and changed the view to Textured.

Here is a quick example using the texture I unpacked from the file. As you can see, the cube doesn't even have a material. This is perfectly legit in Blender but really bad practice as it pertains to asset management etc.

Since the objects are already unwrapped, to fix it, just create a texture and change Coordinates under Mapping to UV. For a bit more information on correct UV mapping, see Blender UV mapping error


Why do normal map ridges become grooves in mirrored object?

I think the negative scaling is getting applied, flipping the normals inside out. Try going into edit mode on the object where the normals are incorrect, selecting everything and doing CtrlF > Flip normals.


GPU render turning out grey when using certain materials

I'm using AMD R9 280 graphics card and I had the same problem.

Reverting to older AMD drivers seems to fix the problem. I reverted from the newest drivers to 16.4.2 version and Blender (2.77) rendering on GPU works again!

You can find older driver versions here: http://support.amd.com/en-us/download/desktop/previous?os=Windows%207%20-%2064

Maybe you can revert to a bit newer drivers and the Blender will still work, I don't know, haven't tested it. I'm just really glad the GPU rendering works again and hopefully AMD fixes this issue asap.

Cheers!


The viewport display only displays in the 3D viewport. The surface and volume panels actually provide shortcuts to edit the world nodes, which you can also examine in the shader editor, when you set it to World.
Surface
The surface color of the world when rendering. This color will be visible in the background when rendering and will indirectly light objects. You can see the indirect lighting on the left face of the cube. To enter rendered mode, press Z in the 3D Viewport and choose Rendered.

Viewport Display
The surface color of the world when using the workbench renderer. This color will be visible in the background when not in rendered mode and will not indirectly light objects. You will only see this color in the background in solid or wireframe mode.
You will also have to enable its display in the Viewport Shading settings.
To enter solid mode, press Z in the 3D Viewport and choose Solid.

Volume
You have select a Background BSDF in the Surface Panel which gets connected to the world output Surface. You will have to select a fitting Volumetric BSDF in the volume panel, since it will get connected to the volume output. A volume scatter BSDF scatters light volumetrically.


The key point to an optical illusion is that it is an "optical illusion" and you usually can't model them accurately. You should create a model that looks right from the camera, but may not look right as you rotate around the model.

For the triangle you are doing look at this

A tip that can help is to use the Blender Internal for rendering. Under the Options panel of the material there is an Invert Z Depth setting. I haven't tried doing the same in cycles.

This scene -

renders as this -

I believe this was created by Ton back in blender 1.70, you get a copy of the file here


Is there a way I could mirror vertex weight data to the opposite side of the mesh? e.g. from left arm to the right arm?

Maybe you are talking about this method but I don't know if there's another one. Let say you want to mirror the left arm group to the right.

If the right group already exists (because you've parented With Automatic Weight), delete it.

Select the left group and copy it.

Now mirror that copy.

Give it the correct name, i.e. with the correct suffix. This way the bone that is supposed to control it will automatically do.


it is possible to rig a character with multiples objects?

Yes you can:
Actually the armature is a modifier that creates relationship between a bone and a vertex group with the same exact name. If a mesh receives form an armature a request to move a non existing vertex group, it simply ignores the instruction.
So you will have to add an armature modifier to every mesh and create as many vertex groups as bones related with that part of the mesh.
You will have to manually assign weights.

For the main part of the armature you can select the relative mesh, select the armature press Ctrl+P and choose "with empty groups"; this procedure will automatically create a vertex group for every bone of the armature marked as "deform", ready to be weighted (you can then delete the unnecessary vertex groups).


How do I use the "Setup Tracking Scene" feature with Cycles?

Yes it is different. I believe that for cycles you don't have directly a "shadow only" material. You have to do some tricks in material settings(with the node editor).


You can pass a list of vertex coordinates to Mesh.from_pydata(vertices, edges, faces) However, you also have to create a new mesh as well as a new object datablock and link them together properly:

Blender 2.8x

import bpy

def point_cloud(ob_name, coords, edges=[], faces=[]):
    """Create point cloud object based on given coordinates and name.

    Keyword arguments:
    ob_name -- new object name
    coords -- float triplets eg: [(-1.0, 1.0, 0.0), (-1.0, -1.0, 0.0)]
    """

    # Create new mesh and a new object
    me = bpy.data.meshes.new(ob_name + "Mesh")
    ob = bpy.data.objects.new(ob_name, me)

    # Make a mesh from a list of vertices/edges/faces
    me.from_pydata(coords, edges, faces)

    # Display name and update the mesh
    ob.show_name = True
    me.update()
    return ob

# Create the object
pc = point_cloud("point-cloud", [(0.0, 0.0, 0.0)])

# Link object to the active collection
bpy.context.collection.objects.link(pc)

# Alternatively Link object to scene collection
#bpy.context.scene.collection.objects.link(pc)

Blender 2.7x

import bpy

def point_cloud(ob_name, coords, edges=[], faces=[]):
    """Create point cloud object based on given coordinates and name.

    Keyword arguments:
    ob_name -- new object name
    coords -- float triplets eg: [(-1.0, 1.0, 0.0), (-1.0, -1.0, 0.0)]
    """

    # Create new mesh and a new object
    me = bpy.data.meshes.new(ob_name + "Mesh")
    ob = bpy.data.objects.new(ob_name, me)

    # Make a mesh from a list of vertices/edges/faces
    me.from_pydata(coords, edges, faces)

    # Display name and update the mesh
    ob.show_name = True
    me.update()
    return ob

# Create the object
pc = point_cloud("point-cloud", [(0.0, 0.0, 0.0)])

# Link object to the scene
bpy.context.scene.objects.link(pc)


How can I create a flowing, rippling water surface effect that follows the curves of a river mesh?

One of the tricky things about rivers is how to animate the water ripples along the path of the curving river. The best way that I have found to do this is by adding a Displacement Modifier set to UV texture coordinates and using a Noise/Cloud texture as well as UV unwrapping the mesh first before extrusion.

There are two important secrets to this technique.

One is UV unwrapping the river water mesh as a straight line first before you alter it to fit the river shape. If you start with a plane, unwrap it right away, then the UV map will stay straight even if you extrude the plane edges to form the curved river shape.

Secondly, you need to enable the AnimAll addon so that you can
animate the UV map.

Once you do that you can set two keyframes for
    the UV map and then animate it moving from top to bottom. In the Tools panel on the left, choose the Animation tab (after enabling the AnimAll addon). Select the UV checkbox, and click the Insert keyframe button at the appropriate frames after moving the UV map.

This will
    move the texture image along the river and will also move the
    displacement along the river. Once your UV's are set and animated you can use those texture coordinates for material textures or displacement modifier textures.

Here's a test scene using this technique:


How to have a string work with the keyboard events in the GE?

Design
You are mixing separate things. This leads to confusion, quirky design and in best case it does not work (as it is not supposed to work together).
Some things you need to know about
Keyboard events
Keyboard events consists of two attributes:

The status (pressed, released ...) and
the involved key.

Keys are no strings. Keys are hardware. Keys are identified by key-codes. Key codes are numbers (not strings).
As nobody wants you to remember all the numbers there are some constants for better understanding e.g. bge.events.SPACEKEY which is key-code 32.
So the working code would be:
p = bge.events.SPACEKEY
# which is
p = 32

I do not really understand what you are going to do. From what I see you try to create code from strings. This is possible. But not what you really want. Here you could do a "light" interpretation, by retrieving the attributes of a module:
getattr(bge.events, "SPACEKEY")

This can become handy when writing keyboard settings into a human readable file format.
Be Aware
The constants do not describe what is printed on the key. For example bge.events.YKEY is not necessarily the key with Y printed on. It describes the key-code (the number) of the key at that place.
To get the printed character on the key of your system you need to ask your OS. It can map the key-code to a string. This happens when you enter text anywhere - even in Blender.
The bad news
I have not found a way to map key-code to character through the OS keyboard mapping, neither with the BGE nor Python.


Set the length to the longest you want the hair to be, and then keyframe the End factor in Particles > Render > Timing:


How to animate camera around a water simulation?

The easiest way to control a camera is to use a curve object:

Create a Curve object and modify it as you like. This will be the path where the camera will move
On the camera create a Follow Path constraint, set the curve as the Target, and you might want to tick the Fixed Position checkbox
To make it easier to control the camera direction, create a new empty (I like the sphere one)
Add a Track To constraint on the camera and set the empty as Target. The orientation is To: -Z and Up: Y
To animate, create 2 keyframes on the Offset slider in the Follow Path constraint

This way, when you change the Offset value the camera will move on the path, and it will always look at the empty.
In your case, put the empty on the water simulation and shape the path as a spiral around it to get a beautiful cinematic camera animation. (The empty can be animated as well if you want)


I am making a rubiks cube and cant figure out how to get the pieces to move correctly

Local rotation is your friend!

Here's what I'd do:

create an 'Empty' at the very center of your cubes
snap the 3d cursor to that Empty:

Set the pivot point to '3d cursor':

Choose 'Local' rotation mode:

Then select your face cubes and rotate, using axis-constrained rotation (i.e. only one axis at a time).  If you use Local mode it shouldn't matter what crazy orientation your cube is in, your rotation will occur relative to the rotation of the cube:

If you rotate using the 3d Manipulator, it'll stay in Local mode as long as you don't change that dropdown.  If you use hotkeys, press the axis TWICE to be in local mode.  That is, press 'R', then 'X' once, then 'X' again, to rotate around the X-axis in local mode.  You can see in my image those red lines shooting out of the faces that show the axis of rotation.

Hope this helps!


How can I animate the camera in a perfect circular rotation around a fixed position?

Yeah, you could...

You could do this with trigonometry. You'd need three drivers: X Location, Y Location, and Z Rotation.

If you want to drive it based on, e.g., the frame, you could pick some constant T for the period (the number of frames for a full circle) and r for the radius, to get:

X Location: r * cos(frame / T * (2 * pi))
Y Location: r * sin(frame / T * (2 * pi))
Z Rotation: atan2(y, x) + pi/2

Create a variable y with settings Transform Channel, Camera, Y Location.
Create a variable x with settings Transform Channel, Camera, X Location.

...however, this is downright silly.

There is no reason you would really want to do this. Here are a couple problems:

There's no need to be dipping into Python and drivers when all you want to do is a simple orbit.
It makes things more complicated and more difficult to maintain. If you want to change the radius, for example, you have to change it in two locations. Same for the period.
You have to have a trusted blendfile. Since Blender 2.68 you have to load a blendfile as "trusted" to use any Python (as you should!).

Better way to do this:

Use an empty, rotation, and a constraint. Create an empty and parent it to the object you want the camera to follow. Then, parent the camera to the empty. All you need to do now is insert keyframes on the Z rotation of the empty to rotate the camera around. To ensure that the camera faces it, add a Track To constraint.

How and why does this work?

When you rotate the empty, it also rotates all its children about the empty. This is exactly what you want — an orbit. The camera will turn, as well, but the Track To constraint makes sure it's in sync with the object. Otherwise, it could be turning at the right speed but always facing out, or always to the right, etc.

Benefits of this solution

If you animate the object that the empty is parented to, the camera will continue moving correctly.
This is really easy to do and takes about 30 seconds.
If you work on a team, people will know exactly what you're trying to do.
You can also animate the camera if you want (move it up or down, in or out, etc.) and the tracking will still work.

Here's what it looks like:


Blender won't copy pose in dope sheet and mirror paste it

About your copy-paste problem: maybe you've enabled the Copy Attribute addon, which seems to disable the normal copy-paste function in Pose mode and Dopesheet. If you have it enabled, use the copy-paste buttons on the horizontal header.

About your armature: First I personally prefer not to activate the Automatic Keyframe Insertion and the Active Keying buttons because I find it a bit disturbing as it creates keyframes as soon as you move a bone, but it's my own preference and maybe you feel comfortable with them.

Also, when you create key poses (in your case frames 0, 10, 20...) I think it's better to create keyframes for all the bones so you're sure that the flipped pose will be symmetrical and won't depend on what happens in the previous and next keyframes.

Now I think the main problem in your settings is your bone called Root.

First I don't understand the use you make of this bone. The root bone should be the hierarchy top parent, meaning parent of the hip, of the IK controllers, IK pole targets, etc... which is not the case here: You only parented Hips to Root, but what does Roots brings to the Hips function? It's not clear to me... So maybe first fix that.

Once done, most of the time, you won't need to use the root bone, except sometimes when you need to move the whole character.

So, what's exactly the bug that is happening when you copy-flippaste your bones? Actually it flippastes the left bones poses to their symmetrized right copies, and vice versa. But it also symmetrizes the pose of any other bones on their own X axis. That's what happens to Root: As you've created a pose for Root, it symmetrizes it on its X axis, and as its X axis points backward, it's flipped upward, and therefore it moves up Roots and its child Hips and all the Hips children!

So once you'll have changed the Root bone settings, and as you won't have any reason to move it, the problem won't happen any more.


If you just want the texture to show, you just need to unwrap the mesh. However, this will leave you with a square texture mapped to a ring, and it wont "follow the path" so to speak.
To do this, things are only a little more complicated. First, unwrap your mesh (select all > U > unwrap). Then go to the UV editing tab.

Select the two vertices at the top of one of the edges that is on the side (because it's side edge is perfectly vertical). Press S + Y + 0. This will make the two points at equal "height" on the y axis. Do this for both the top and bottom edges, so you're left with a rectangular shaped quad.

Then, select the whole mesh, making sure the quad you created is the active face (lighter color). If you need to make it active, just un-select and re-select the face - just make sure all the faces are selected when you're done. With your mouse over the 3D view port (not the UV map), press U and select Follow Active Quads. Confirm in the box that pops up and your UV map will be straightened.

From there, just scale the UV island back to size and place it where you want in a the UV space. Add a texture and you're done.


Blender for Engineering: Numbering and naming objects in blender

That's what grease pencils are inicially for. However, I don't think there is any way to type in text although there are some addons (I never tried  this myself) and discussions.


Rename folder/file in blender file browser?

You can do this using Ctrl+LMB. Simply hold Ctrl and click on the file or folder you would like to rename.


Here's one way. This assumes that the long axis of your glow stick is the Z axis.

The Texture Coordinate node will give you a value for each dimension that varies between 0 and 1, in the form of a color map.

The separateXYZ node will give you just the Z value.

The ColorRamp converts that value into a single color.

My color ramp goes from black to white, but you can change the color

Select the color ramp
click in the vicinity of one of the two pointers
click on the color patch just about the Fac input
Select a color from the color picker

There are many ways to adjust the color ramp.  You can move the pointers around.  THe most useful to you might be that moving the right pointer farther left will reduce the area where the fade happens.


Yes, you are right. The operator draw method is only available in 3d view and not in node editor.


Clothing Not deforming in engine, using mesh deformer

The mesh deform modifier is a custom piece of blender functionality and is not supported outside blender.

Only shape keys and the armature modifier are reasonable reliably supported in cross application use as methods of mesh deformation. These are the only ones supported in the fbx file format that I am aware of.


Using a bézier curve to raise/lower height of vertices?

You can, but you will have to use a workaround.

The principle is using a Vertex Weight Proximity modifier to influence displacement strength.

Issue is unfortunately you can't really use a bezier curve object directly, so you will have to use a mesh object with an Array modifier plus a Curve modifier to affect the displacement.

Just array to any mesh (possibly a simple cylinder) and add an Array modifier set to Fit Curve. Then add a Curve modifier on top of it, point it to the same bezier curve as described here.

On your (soon to be) deformed mesh create a vertex group and add all vertex to it. Then add a Vertex Weight Proximity modifier set to control that same vertex group in Distance to Geometry > Face mode.

Now add a displace modifier influenced by the above vertex group as described here, adjust values and distances as necessary.


Mirror modifier is not working how expected?

You're mirroring off the wrong axis. Blender guru is mirroring off x, you seem to be mirroring across y. You may also need to apply the object position (ctrl+a, object position) such that the origin of the object (where the mirror modifier works off of) is at the world origin.
Edit - Additional Explanation of the Mirror Modifier
An object's position can't easily be calculated in 3d space: Any point in 3d space, even if on the object, is unrepresentative of the vast majority of points on the object. So when we say an object is at x coordinate 2, we really mean that the object origin is at x coordinate 2. An object's origin is just an arbitrary point that we tell blender to use. It could be absolutely anywhere (generally moved with the 3d cursor as described in the comments), and the mirror modifier interprets it as the center of an object. So if you have a single point at (0, 2, 2) and its origin is at (0, 0, 0), that point mirrored across the y axis will be at (0, -2, 2). The mirror object does this with every vertex of the object. So if your mirror is showing up in an unexpected location, it'll be because your object origin is an unexpected location. If you want to change the position of the object without effecting the origin, just go into edit mode (and select the whole object with a) and move it.
Then there's clipping and merging, which are ways to tell the mirror modifier that if a vertex has crossed the axis which it is being mirrored on (the axis on which the object origin lies), it should merge it with the mirrored vertex. If you want to make something perfectly symmetrical, these are often completely necessary.


Can we disable mipmapping at the render?

You need to disable "GPU Mipmap Generation" as well. Without it disabled, the mipmap will just generate using GPU, instead of CPU.

As with many other elements of Blender, there is an option to toggle mipmapping in properties as well as user preferences. Go to properties> Texture> Image Sampling. (The image below is as it appears in Blender Render.)


Is there a way to map a floating point value using a Bezier curve with nodes (Blender 2.8)?

A potential solution is to use the RGB Curve node, but focusing only on one of its channels. In the example below, I am passing as input a floating point value in the range [0.0, 1.0], and the node tree below does the following

Feed the input floating point value to the RGB Curve node (since the input is one-dimensional, we focus on only one of the RGB channels; red in this example)
Separate the output into the three color channels (RGB)
Isolate the red channel (at this point the output is still in the same range, [0, 1])
Multiply the red channel output by a (problem specific) scaling factor


How can I import models from Anim8or into Blender?

Transferring data is just a matter of finding a format that both programs can use. Some formats have better support for some features than others (like materials, animations, and armatures).

It would appear that Anim8or can export in 3DS and OBJ - both can be imported into Blender, menu File -> Import -> 3D Studio (.3ds) or menu File -> Import -> Wavefront (.obj).

Both import addons should be enabled in Blender by default, but if they aren't, open the User Preferences and look under addons to enable them.

I would export in both formats and see which one gives a better result in Blender. I would also expect that the mesh would transfer OK, but then expect to do some manual work to re-make the textures in Blender.


Smart UV Project works for me on 2.79. I added a primitive cylinder Edit/Face mode/deleted the cylinder top face. Back to Object mode/added "Solidify Modifier" (BTW hate that name), applied "Solidify Modifier". Back to edit/face mode, select all/apply Smart UV Project at default settings. Result is fine.

So are you saying that the faces/verts of the outside of the cylinder are locked to the inside faces/verts?


Why do my video and audio lenghts not match when I cut?

Set your project Frame Rate properly to match the one of your footage.

Mikeycal Meyers has got some great tutorials on this topic. He explains it pretty well in #2 - Blender Video Editing (Importing video) starting at 3:35. If you want to do speed change stuff instead you should follow his #24 - Blender Video Editing (Speed up & Slow Down Audio/Video | Snap Strips option)

So to fix it for you, you need to calculate your footages frame rate and set it up in Blender. You can do so by dividing your Audio Length (which is 42389 as you can see on your teal/lightseagreen/darkcyan colored Strip after the "|") by your Video Strips Length (that 3284 next to your darkblue strip) that is about 12.907... When you then multiply this result by your current Frame rate (which is 30 right now in your Properties) to get the Footages Frame Rate. Which is about 2.32418... in your case. It seems to be a timelapse Video Capture with a pretty low frame rate.

Here the result isn't a already predefined common Frame Rate. So you need to select a "Custom" Frame Rate in your Properties and leave this FPS setting at 30 and use this 12.907... as your Framerate base below (you can directly enter "42389/3284" into the box and let Blender do the math. Your result should be the "Custom (2.34 fps)" in the Frame Rate Dropdown box.


The best topology I've personally found for this kind of case (hole in a round surface) is the following one. So you need to create a bevel on the corner, then join some vertices and delete some edges:


Boolean object visible in rendered image

It looks like your object isvisible in render, but not in viewport. In any case it should still exist in the object list.
Try to find objects hidden in viewport but not in render:

Then you can hide them in rendering by clicking the little camera, or just delete them.


Colors/Lights drastically different in render (2.8 Eevee)

Try disabling "Bloom" or adjust it's settings and see if you have the same issue.


Based on the "... to avoid having unassigned meshes" part of your screenshot, it looks like the manual is asking you to delete the widget (WGT) objects.

This is a collection of objects at the very last layer of the 3D view window. They aren't really bones, but meshes meant to be indexed as bone shapes to make them easier to identify.

If this doesn't work, you may have to delete both the widgets and remove the links to the widgets from the control bones. I hope not, that last bit will be tedious.

To delete the widget links, select a bone and go to Bone Properties >Display> Custom Shape and click the X. Do this for every bone.

I mention this last bit because Blender tends to save these custom shapes internally, so they can appear again even if the widget object is deleted.