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How can I set the geometric resolution of a primitive?
I'm having trouble creating a high resolution sphere in Blender.
I can create a sphere with Add -> Mesh -> UV Sphere.  This sphere will be viewed very close to the camera, and it's obvious (in Unity) that the object is not round.
There doesn't seem to be any way to set or increase the number of vertices / segments in the sphere either during creation or afterward.  Is there a menu I'm supposed to be seeing that's not in my view?

^ This is all I'm seeing in Blender.  No obvious way to set the sphere's resolution.

^ Sphere looks pointy in the game.

Blender 2.8
In Blender 2.8, after adding a UV sphere, a flyout appears on the bottom of the 3D viewport:

I have no idea on how to access that with a keyboard shortcut.
earlier versions
If you press T before adding the UV sphere, you should see the "Transform" panel which allows you to set the  segments and rings.

If you already have the UV sphere and want to modify it instead of creating a new one from scratch, you could use the Subdivision Surface ("Subsurf") modifier.

Perfect.  The simplest things are always the hardest to find info about (like blender keyboard shortcuts).

Right after the mesh is added, press F6 to get a pop-up dialogue box to edit the mesh primitive

F6 doesn't seem to do anything in my blender.

Only work when you just added the mesh, you can also try pressing LMB on it

Doesn't work at all. Does Blender's UI change completely every few months?

@WouterLievens: hopefully not. 2.8 was a major redesign regarding usability.

In Blender 2.81, it’s F9, not F6. But it only works when the panel is available in the bottom left corner anyway, so it seems largely pointless.

Thanks! I wasn't aware 2.8 was such a big evolution.


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Separate a curve
I have 2 objects that look like they are grouped or linked somehow but I'm not sure how to separate them?

In the box in the top right, you see 'Curve 037', I want to take out 'Curve 036' underneath and then delete 37.
Thank you.

It looks like curve 036 is parented to curve 037.  Select the 036 curve in the 3D window and press ALT-P.  Click on "Clear Parent". The two curves will be independent again.

That done it, thank you. I tried it before but I must of been selecting the wrong object to separate. Cheers!

source: Stack Exchange

license: Creative Commons - Attribution Share-Alike - https://creativecommons.org/licenses/by-sa/3.0/

sort: votes


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Cast a shadow with HDR world lighting?
I have quickly created a bed in Blender and I'm using HDR lighting on the World node in Cycles, is it possible to create a shadow underneath the bed without adding more 'light' to the object?
So basically, the bed looks exactly like the below but it has shadows cast underneath / around it.

Place a plane under the bed, so there is some geometry to cast the shadow on. You can also chcek shadow catcher in the object info tab to get only the shadow and not the actual plane

Thanks, is it also possible to make the world lighting not cast shadows and then use a light source to cast shadows instead?

license: Creative Commons - Attribution Share-Alike - https://creativecommons.org/licenses/by-sa/4.0/


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How can I recreate this lighting?
We have had this bed created for us by a third party and I'm wondering if it is possible to recreate this lighting in Blender Cycles? I create simple bed mock ups from drawings and this would help tremendously in their presentation.
I have looked at various guides and tutorials but haven't found anything tailored to my needs.

what do you mean " recreate this lighting"?

There is barely any lighting to go by, that looks like a drop shadow edited in Photoshop

Possible duplicate of Cast a shadow with HDR world lighting?

@moonboots it looks like a 3D rendered model on a plain white background?

are you going to create a 3D object like this one? It can be either a transparent background and the white background + shadow can be created in photoshop, or create a white plane in Blender which is flat then goes up

@moonboots I do create 3d objects like the one above, if I were to use the white plane option, is there someway to make it just pure white without the shadows from lights etc affecting it?

1) With Blender (Cycles Render) and Photoshop you can do it this way:

Create your object.
Create a plane under your object. Keep this plane selected. In the Properties panel > Object > Cycles Settings, enable Shadow Catcher.
In the Properties panel > Render > Output > Choose PNG and RGBA so that you can have a transparent channel, and in Film > enable Transparent.
In the Properties panel > Render > click Render.
Open your image with Photoshop, you have a PNG file with transparency and there is a shadow under your object.
In Photoshop, put a white layer under the object layer.

2) As Risingfall says, if you know how the Compositing works, you won't need Photoshop, just use a white background and an Alpha Over node.
3) A more basic solution is to play in your 3D scene with a structure of planes that either have Diffuse shader so that they can receive shadow, or Emission shader, so that they stay 100% white.

Or you could use the compositor to create a white background, using the Alpha Over node.

Yes you're right, it's a little bit more complex though, as you need to know how the Compositing works

Thanks, I can get the object highlighted like the one above using emission planes but they create their own shadows so its hard to recreate the one like in the picture above unless I do photoshop trick like you suggested earlier

I would say that the Photoshop trick is the easiest, the Compositing is the most intelligent, and you can get what you want if you tinker a bit with Diffuse and Emission shaders

all_licenses: Creative Commons - Attribution Share-Alike - https://creativecommons.org/licenses/by-sa/4.0/


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Blender Eevee reflection plane gives warped reflection
I want my ground to have a nice reflection, but the reflection plane is acting very strangely (See photo below). What's also weird is that the reflection plane works for most of the scene. When I add the plane I can click around the timeline and it seems like it is work, but when I play the animation through from start to finish the reflection breaks 2/3 through.
I've tried to solve it a few ways, which don't work:Restarting Blender; Downloading latest version of Blender; Deleting plane and creating a new one.

There was a problem with my material. I had an image sequence that was input into a normal map. For some reason a few frames of my image sequence were empty (it looked like a missing image) which would through off my normal map and give a weird reflection.
Specifically the problem came because my image sequence started at frame 31 and went to frame 220. The offset was set to 31 so and it ended up adding frames that I never had.


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GPU rendering out of memory
Why do I have "Out of memory" crash while GPU rendering with the memory peak of 356 when by graphic card has 2GB of memory?

I don't have an answer to your actual question, but you might get through the render by decreasing the tile size by increasing the number of tiles in the render properties. This should reduce the RAM requirement.

Yes, I know, but it will also increase render time. Anyway, thanks for your answer.

I was thinking about it some more. Is there a utility that can tell you what other things the GPU might be working on? I wonder if something else might be occupying the rest of the RAM. Also, have you tried running it on the command line?

What operating system are you on, what is your graphics card brand and model? What drivers are you using, are they up to date? What other software is running while you render? There too many variables and too little info to give you any kind answer. It may be that Blender is reporting memory usage wrong, there may be other applications using VRAM, Blender itself may also be using additional memory for viewport and UI, it may also be a bug

Win10
GTX 960 2GB

As first I must say only for correctness: Does not matter, how much memory have you graphics card. Important is how much free memory have your graphics card, when you start render. Keep in mind: system need some video memory for running.
You are not only one who have this problem. I thing Blender have some issues with freeing VRAM. I used Win and now I'm using Linux and it's the same. What help is restart Blender.
About peak of used VRAM - I don't thing this is correct number in case of error. From my experiences, if Blender give you "out of memory" error, this number is incorrect. You can determine exact size of scene by switch to CPU rendering and you can see how much memory is really used for your scene.

best way for work with render and GPU is to use integrated GPU (o a very cheap video card) for the system and use the powerful GPU just for rendering.
in this way GPU is just used for rendering and nothing else.
if your computer have a integrated VGA try to plug monitor in this one and let the 2GB card unplugged.
try to start rendering in this way

all_licenses: Creative Commons - Attribution Share-Alike - https://creativecommons.org/licenses/by-sa/3.0/


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How can I create a 3D radial "beams" with shader nodes?
I would like to create a proceedural texture in which "beams" eminate from the center of an object - think of light beams coming out of a point light source. The following node set-up does this perfectly in 2D:

However if applied to a sphere you see that the beams are only eminating from the center on the X/Y plane, not the Z axis.
If the "beams" eminated from the center they would appear as spots on the surface of a sphere like in my example.
Please note: I realise I could use voranoi if spots on the surface are my end goal, but I'm intending to use this texture to control the density parameter of a volume shader, so the solution needs to create "beams" radiating from the center of the object outwards.

Try this - it's a bit hackish, but it might work for you. Start by breaking a radial gradient into "slices" using a ColorRamp set to constant. Use as many "white bits" as you need.

Take the result and multiply a Normalized wave texture (on the Z-axis) over it to chop up the beams vertically. The Normalize (Vector math) node makes the beam "cones" point on an angle.

Lastly, multiply a spherical gradient over the whole thing to give falloff to the edges.

Alternatively, you could use a Volume Scatter node (instead of an emission), and place a point light right at the center:

I was hoping there would be a way to do it by manipulating texture coordinates, but I've not come up with anything better than this approach which does indeed create the effect I'm after.


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Pre-displacement normals
The "Geometry" shader node provides normal information for the geometry being shaded. This can be useful, for example, to mix a snow shader with a rock shader depending on how "flat" the geometry is (angle relative to Z axis). This normal information seems to be calculated after any displacement is applied by the shader (Cycles). In my case, I would like to get the normal information before displacement is applied. Is this possible?

The way with Geometry Nodes as the given answer by @Nathan suggests is the only way as far as I know, at least you cannot preserve them in the Shader Editor itself. Because the order before rendering is always first comes the original mesh, then the modifiers and afterwards the materials at last, so everything you do there with normals is executed on the altered mesh.

Assuming we're not using custom normals or sharp edges-- which would be weird with true displacement-- we can capture the vertex normal in geometry nodes and use it in the shader:

The geometry nodes are evaluated before any shader based displacement.  Our output will be in object space, giving us interpolated values, so we need to normalize the vectors and transform into world space in order to use them the same way we'd typically use a normal in the shader.


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How to limit fluid cache to used frames
I’m using a smoke simulation in my scene (animation), but I only need to use the simulation after it has reached a certain state. It takes around 2000 frames for the smoke to reach the point where it looks the way I want for my render, and after that I want to use the next 150 frames or so.
Baking the simulation takes a long time and takes up a lot of drive space, and I don’t need the majority of the calculated frames. In the cache settings I’ve set the start frame to 1, the end frame to 2150, and then the offset to -2000. This means that frame 1 of my animation is frame 2000 of the simulation which is what I want. However, every time I free the cache to tweak settings and hit re-bake the simulation re-calculates all 2150 frames.
Is there a way for me to keep frame 2000 as an initial state and just re-calculate the subsequent frames I’m using from that point on after I change settings? I realise that changing a setting means frame 2000 would be different, but most of the time that doesn’t matter - as long as the initial state looks OK I just want to calculate subsequent frames with the updated settings. Is this possible? Thanks.

Blender's fluid simulation can't stop / resume for now ... so I don't think you can start (resume) from a middle of simulation.
Smoke
In your case, there is not a chance by default at the moment (or without someone to hack a code).
Liquid
For liquids you can try Flip Fluid $ addon (if you don't care to invest) ... It resumes from certain frame ... in step of 50 frames.

The list is sorted in a weird order, but seems to be a cosmetics :)

Thanks, I’m not against investing in good tools but from my quick research I can’t see that flip fluids does smoke/gas simulation. Their website talks mainly about liquids. Do you know if it can do smoke/fire also?

Ah, sorry ... My fault ... Right, addon is about fluid only ... Originally I commented it it is not possible, later I started to think about the resume feature and accidentally stacked with your title "fluid cache".  ... So try to check Embergen ...I'm not sure if it can start from certain frame, but since it is realtime, it could speedup your workflow.

@vklidu Just for information, in physics the term "fluid" refers to liquids, gases and other materials that continuously deform (flow) under applied external forces. So actually Flip Fluids is about liquids, not fluids in general - despite the name, but I guess it comes from the addon using fluid mechanics to calculate the simulations. And on the other hand it is correct that Blender has its liquid and gas simulations summarized under the Fluid physics.

Thanks @vklidu, I will check out Embergen. If resuming smoke simulations is not possible in Blender then I'll mark your answer as correct. But perhaps it would be good to edit it to remove the reference to Flip Fluids?

Thanks, I wanted to delete my answer, but then it will be poked by system here, so you can probably delete your question (until that I just edit it) :)

@GordonBrinkmann ... sure ... thanks :) I know and I'm not saying it is wrong ... that's just me :) My brain automatically sticks to liquid when I see fluid.


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How to improve performance when rendering freestyle lines only?
I have a moderately complex scene that I wish to render in a "line only" style like blueprints. I've enabled freestyle rendering and stuck with the Workbench render engine given that I don't actually need anything other than the freestyle lines. There are no lights or textures in my scene and I only have a single line set. I'm rendering the lines as a seperate render pass and compositing them with a flat color background using an Alpha Over node in the compositor. The result is what I want, but it is very slow. Nothing in my scene moves other than the camera, so I've enabled View Map Cache as per the docs. But still, each frame is taking several minutes to render.
My PC is reasonably high spec (rtx 4090 and AMD 7700) and I've enabled GPU rendering, yet I'm only seeing a couple of cores being utilised during rendering and the GPU is barely used at all. I have plenty of free memory so I don't think paging is happening. I read in an older question that freestyle line rendering is a single core CPU only activity, but that was pre Blender 3 and I have read information elsewhere which seems to contradicted this so I'm not sure if that is still the case or not.
Is there anything I can do to speed up these renders/better utilise my hardware? Are there optimizations to speed up rendering if you only need the freestyle lines, or is this still a single core process that is inherantly slow?


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Blender parent problem
I used Blender2.79 and I think I just find the problem.
I have two objects and I want to make parent relations to each other,
when I used CTRL + P, the child's transform location still relate to the world's location.

However, when I manually use (properties -> object -> Relations: Parent) and select the object that I want to set it to parent. It used the parent's transform.

I belive those two ways are doing the same things and I miss the setting or this is a bug??

I just realize if I used (CTRL + SHIFT + P) and it can used parent's transform as world transform.

This is from wiki:

At the very moment of establishing a hierarchical relationship between
  objects (parenting), the transformation coordinates of the child
  object remain unchanged, and yet this object doesn't change its global
  transforms visually (location, orientation or scale), though its
  reference "world" has changed from global origin (zero transforms) to
  the global transforms of the parent.
Origin of unparented objects is the global origin: global (0,0,0)
  location, zero rotation, and unity scale. After being parented, the
  new origin should be that of the parent. And it is. But a correction
  matrix is applied to the child, so that the new reference point is not
  the global transforms of the parent, but the global origin. This
  correction matrix is applied to the global transforms of the parent
  before applying them to the child.

This correction matrix called Parent Inverse
You can do this operations with Parent Inverse:
Alt + O (clear origin) - this operation clears Parent Inverse and makes object go to the parent location.
Ctrl + Shift + P (Make parent without Inverse) - it's like what you do in properties -> object -> Relations: Parent. Or like Ctrl + P and Alt + O and Alt + P Clear Parent Inverse in one comand
Alt + P Clear Parent Inverse - Like Alt + O but for rotation and Scale.
Why Blender using Parent Inverse?
Let's try 2 objects  with Parent Inverse:

and without:

As you see, transform matrix, applied on parent object without inverse, makes child object distorted. If you want this effect - you are welcome, but mostly, we don't want it

Select Active Tool and Workspace Setting > Option > Transform > Uncheck Parents


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How do you get fixed bends on a low poly model?
I'm working on a very low poly model (Minecraft style) for a game, I've rigged it by parent with empty groups, then manually assigning bones to groups.  I want to have bend in the arm, but when I do so the joint "pinches"

Notice how the elbow isn't as thick as the rest of the arm.  How can I fix this?
Blend file

It is the way vertices are deformed to obtain a smooth transition angle between the two parts of arm. If you rotate an edge, by projection, it will look like the size is smaller from the hand point of view. (Simple trigonometry rule.)
On a average higher poly model, you would have more vertices on the elbow, with different weights depending of proximity with the other bone. So the arm have same thickness and elbow will smoothly do transition.
In you case you would need the join edge to change size to keep arm thickness, but even if it is possible, it could give weird results.
In this case, since your inspiration come from minecraft, I would suggest you to separate each bone as a distinct piece (with different object or in one, like you want).

If you don't want same minecraft bone separation effect, you'll need to add more vertices to elbow.


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mystery dot unknown problem
hello I've been modelling a face only got from the eye brows to the mouth. around the left eye there's a dot that is visible only in object mode not in edit mode I thought it was a vert that some how got there after going to edit mode though it was not there when selecting the face the dot seems to also become selected but still not visible in edit mode when clicking on the dot in object mode it also selects the face so they must be connected somehow I have a mirror mod and a sub surf on the mesh

You don't just have a Mirror and Subsurf modifier on your mesh, you also have a Particle System. The dot you are seeing is one of the emitted particles.
To remove the particle system (as it sounds like you didn't intend to have one) first click the highlighted button below to go to the particle system settings:

Then click the minus button to remove the particle system from your object:

If my answer has helped you can mark it as 'accepted' by clicking the tick to the left of it. See: https://meta.stackexchange.com/questions/5234/how-does-accepting-an-answer-work


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Is there any way to duplicate bones radially?
I'm building an object that has radial symmetry, and it's armature would have the same symmetry. Is there any way to automatically duplicate bones radially after building the initial piece, or do I simply have to duplicate and position by hand?

If you would like to see a beginner video tutorial series this is one ... https://www.youtube.com/watch?v=lY6KPrc4uMw&list=PLda3VoSoc_TR7X7wfblBGiRz-bvhKpGkS ... If you browse titles you might look for ... center of rotation ... armature bones ...

Just an idea... you can dupliface the armature:

Here I used a cylinder: the number of faces will make the radial distribution.
Once original armature is ok, you need:

to select the cylinder and make duplicate real
to select the duplicated armature and make them single user
then join them:

Though, I don't think there is a mean to duplicate the eventually created animation on the original armature by this way...

Yes.  You can duplicate radially in two steps.
Duplicate Shift Dand Rotate r.
Edit Mode with a single armature.
You know the radial center.  Place 3D cursor to radial center.
Change center of rotation to 3D cursor.  This is indicated with arrow in image.
Duplicate correct bone, or bone sequence. Rotate in the appropriate plane a number of degrees which can be typed such as precise 30.
The cyan bones have been specified as not connected to the parent.
Duplication with Shift D
When finished change your center of rotation back to your desired settings
You could place a temporary cylinder for casual eyeball inspection or snap the cursor to locations on the cylinder.  See Blender snapping capabilities.
Please know I am at this point giving high level suggestions and not menu names or keystrokes.  The video series suggested above will save you time and energy.

I actually was already doing this when I posted the question, but @lemon's more automated solution was what I was looking for.


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How to plan meshes - topography
I am just starting 3D modeling and I am having a bit of trouble planning my meshes so that they flow well and are built in a way that supports the model.
I keep running into "trouble spots" where my meshes kink, pinch, or twist up. I have been unable to find resources that explain the best places for loops/cuts/etc.
I understand it will be dependent upon the model, but I would like to know the best way to plan the flow of meshes and deal with common situations.

This is a tough subject, and it has some differing approaches to it. My best advice to you is to play with your bending points, and play with different NGONs. Quads are usually preferred in animation, as the deformations are usually controllable See THIS LINK for more info.

I consider this to be one of the best topology and modeling "good practices" compendium http://topologyguides.com/


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Some of the normals have been flipped when in tried converting my model to low poly
I have used decimate option for converting my model to low-poly after doing that some of the normals have been flipped. I haven't understood that why is it happen. can anyone suggest me solution.
Thanks in advance.

It would help if you show screenshots of the model. Generally Decimate modifier if you used it doesn't flip normals, probably what happened is that shading for the left faces corrupted for some spots. But it's a guess with known information

the only case it might do that is if you have some kind'a concave shape with less polygons. Try adding a subdivision modifier before the decimate so you could increase the ratio trying to get similar results without the normal problem, but it is just a guess.It'd would help if you could provide a screenshot

You can easily flip all your faces into one direction by clicking Ctrl + N
This should solve your problem.


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joining 2 parts without losing their textures
I am new to blender, still learning.  its a long process
I have 2 complex pieces created, each with a UV-map and texture.
- if I "join" them the new piece has a single messed-up texture, 1 UV map
How can i get a new UM-Map that has the previous faces still correct ?

When you join two meshes together, your parent mesh will be the default material.
You need to create a second material for your second mesh and use the UV Map node under Input to tell it which UV to use.

It's a good idea you give each UV a name too.As you can see, whichever UV is highlighted is what you can see in the viewport. You can ignore that. It will render both.


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Getting bpy.ops.anim.copy_driver_button() working
I am trying to copy the following driver in the Shape Keys section under Properties/Data: Look at the image below

When I right click it and go to copy driver it works, and it shows the command to be bpy.ops.anim.copy_driver_button() but if I run this command in the python shell it does not work. I know the problem has to be related to the context, so I tried to write an overrider dictionary and it is still not working:
window = bpy.context.window_manager.windows[0]
screen = window.screen
area = screen.areas[1]
region = area.regions[1]
space = area.spaces[0]
override = {'window': window, 'screen':screen, 'area':area, 'region':region, 'space_data':space}
bpy.ops.anim.copy_driver_button(override)

Now this does work if I bring up the command and I place my cursor over the purple button in the row where shape.L.000 (what I am trying to copy). If the cursor is not there it won't copy.I tried looking at the source code to see what is going on but that hasn't helped too much. Am I missing something in my override dictionary or is this doomed not to work? Any help would be greatly appreciated! Thanks

It may help to show a little more context into what your driver is calculating (where your driver properties are being watched). Because not all things drivers are fully implemented in Blender, the context of your calculation may have a lot to do with the solution on this question.

Hi @RickRiggs basically its controlling the z-component of a vertex in a cube. The driver is connected to an armature so when you translate the armature in the z-direction it raises the vertex in the mesh (the cube in this case). Basically the driver controls the following value:
bpy.data.shape_keys["Key"].key_blocks["shape.L.000"].value

Okay this is a fairly simple solution then, I'm going to point you there instead of answer it yet, because I'm on my phone and not in front of blender (I will have to circle back around on this).
You need to get into the animation_data of your objects. This has driver, expression, and variable properties within. The big tip here is that you need to create a new variable before the expression will actually work. To get at these it's going to be something like:
bpy.data.objects["Cube"].animation_data

Here is a quick append to this answer for now to help you understand the data structure. However before you copy and apply this data to another object there is more to prepare on the "OTHER" object.
Still planning on circling back around on this to finalize this lacking part of the answer.
c1 = bpy.data.objects["C1"]
# This is the reference to my Original Cube with the Driver

dr1 = c1.animation_data.drivers
# This is the Driver collection of my Original Cube

dr1[0].data_path
# This returns 'scale'

dr1[0].expression
# This simply returns my expression 'var', because I am using a 1:1 mapping of another object's scale factor

dr1[0].driver.variables[0].name
# This returns the first (and only in this case) variable that I have named in this driver 'var'

dr1[0].driver.variables.items()[0][1].targets.items()[0][1].transform_type
# Returns 'SCALE_X'

dr1[0].driver.variables.items()[0][1].targets.items()[0][1].transform_space
# Returns 'WORLD_SPACE'

Without being able to confirm this yet, I'm going to recommend that you explore the following approach to get the copy:
For the sake of my code above, please follow my case (ultimately it should follow suit in yours).
I'm going to reference a second Cube whose name is "C2".
CONFIRMED
So for the prep on this object, before you can copy the data try:
c2 = bpy.data.object["C2"]

#If you were to create it manually -> c2.driver_add('scale', 0)
#Since you are copying do something like:

dr2_path = dr1[0].data_path
dr2_index = dr1[0].array_index
c2.driver_add(dr2_path, dr2_index)

#Now get reference to your new driver & Create a new Variable
dr2 = c2.animation_data.drivers
dr2[0].driver.variables.new()
#by default this should be 'var' if this is the 1st.
#You should now be able to copy the expression, target, etc... over from c1

dr2[0].driver.variables.items()[0][1].type = dr1[0].driver.variables.items()[0][1].type
dr2[0].driver.variables.items()[0][1].targets.items()[0][1].id = dr1[0].driver.variables.items()[0][1].targets.items()[0][1].id
dr2[0].driver.variables.items()[0][1].targets.items()[0][1].data_path = dr1[0].driver.variables.items()[0][1].targets.items()[0][1].data_path
dr2[0].driver.variables.items()[0][1].targets.items()[0][1].transform_type = dr1[0].driver.variables.items()[0][1].targets.items()[0][1].transform_type
dr2[0].driver.variables.items()[0][1].targets.items()[0][1].transform_space = dr1[0].driver.variables.items()[0][1].targets.items()[0][1].transform_space

Here's the proof of the rest of this code in play:

This is a nonetype, are you sure this is the right expression?

@InsigMath Please see the latest append to the answer. Just not at a place where I can spend any time on this yet.

Thank you for the detailed answer, I will check this out when I have some time later today!


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Finding a specific fcurve!
I am trying to develop an addon that involves placing a keyframe on a specific fcurve (like for example the X Location) and then making changes to the coordinates of the handles of that keyframe (as well as the successor and predecessor keyframes) but the problem is if there are multiple fcurves how do I know which curve I just added a keyframe to.
I know how to place the keyframe using bpy.ops.graphframe_insert but if I want to script some change to the newly added keyframe just looping through all the fcurves isn't helpful as they do not seem to have properties indicating exactly what fcurve they belong to.
Just to give an example: A user places the keyframe for the Y Location and there are 9 fcurves I can place the keyframe just fine in the Y Location fcurve but I cannot find a way to distinguish one fcurve from another unless I know the exact index.
Any help would be greatly appreciated, thanks!

https://www.blender.org/api/blender_python_api_current/bpy.types.ActionFCurves.html#bpy.types.ActionFCurves.find

This is exactly what I need! Thank you very much @batFINGER!


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Debugging Blender on VSCode
I am trying to debug blender via gdb on Visual Studio Code. I have a launch.json file and it will open up blender but immediately close. I am not sure what is going on, has anyone successfully . Here is my json file:
{
// Use IntelliSense to learn about possible attributes.
// Hover to view descriptions of existing attributes.
// For more information, visit: https://go.microsoft.com/fwlink/?linkid=830387
"version": "0.2.0",
"configurations": [
    {
        "name": "(gdb) Launch Blender",
        "type": "cppdbg",
        "request": "launch",
        "program": "path/to/bin/Debug/blender.exe",
        "args": [],
        "stopAtEntry": false,
        "cwd": "${workspaceFolder}",
        "environment": [],
        "externalConsole": false,
        "MIMode": "gdb",
        "miDebuggerPath": "path/to/bin/gdb.exe",
        "setupCommands": [
            {
                "description": "Enable pretty-printing for gdb",
                "text": "-enable-pretty-printing",
                "ignoreFailures": true
            }
        ],
        "preLaunchTask": "Build Blender Debugger"
    }
]

}
It seems to build but when it launches Blender it immediately closes. Any help would be greatly appreciated!

I found the issue is using gdb ... When I changed the debugger to be used cppvsdgp I was able to get it to launch and debug.


text:
See t-s and t-v graphs of motion tracking points
Is it possible to display the movement of the tracking points of Blender's motion tracking function as a graph (probably in the graph view tab) with time[seconds or current frame] on the x-axis and either distance covered or velocity on the y-axis?

This may help you get on the right track (the idea is to bake the tracked object's motion to an animation curve): Getting raw data from object track
You may need to write some python at some point, depending on the information you want to get out.
Edit to add more info quoted from the linked answer:

You can use a Follow Track constraint to 'project' a single track onto an object.

track your point, you dont need to solve the camera.
make a plane, and position it perpendicular to the camera... how you want to set this up is up to you, but it will effect the numbers you get out at the end.
add the constraint to an object, i just used the default Cube, and refer to the image bellow on how i set it up.
in the viewport image, I have calculated the motion paths, and you can see the path of the track is on the plane.
click the Constraint to Fcurve button, and it will bake the constraint to XYZ values. Edit: Some times this button doesn't work. An alternative is: Search->Bake Action
you can then write some python to convert your animation to CSV format.

Thanks for the link, it helped me to move on. The only problem is now, that I can not get the right unit (m or cm) and I do not see any possibility to define a given length in the video to be xyz Meters.


text:
How Would I Join The Selected Edges Together
As you can see the lines are not the same, on the bottom it has bigger spaces and on the top its smaller, please help me out i tried everything i know and am stuck.

If you have enough endurance and persistence, you could fill (F) every space.

There are several, almost infinite, ways in which the profiles can be joined. Some maximize certain properties and some not... What's the topology you are looking for? Could you sketch a small sample or describe it? And how many vertices are there for each circle?

@Bradman175 Bad idea. Since the loops don't all line up, there would be lots of irregularities from triangles.

@TARDISMaker I'm aware of that.

Possible duplicate of How to connect faces between 2 edge loops?

@Bradman175 You do realize that because of that it won't turn out correctly, right? (and if you did, why suggest it?)

I am not aware of an automagic way to do this, but here is a workaround: In edit mode, select one edge segment from the lower piece and the corresponding edge segment from the upper piece. Use [F] to fill a face between them. Continue doing this around the model. Because of the difference in vertex count, you will occasionally need to fill a triangle instead of a quad.
Here is some information on filling faces in edit mode:
https://www.blender.org/manual/modeling/meshes/editing/basics/creating_faces_and_edges.html
Edit: Filling faces is still useful, but Bridge is way better.
In edit mode, you'll select the edge loops, then Mesh > Edges > Bridge Edge Loops. Here's some information on edge tools—scroll down to the Bridge section: https://www.blender.org/manual/modeling/meshes/editing/edges.html

Although this would work, I think the OP is looking for a more efficient way.

Edited to add better way.

What i had done was quite stupid, what i did was a quick remodel of that bottom part, and somehow i managed to fix it a little, as you can see in the picture there's one spot that is not like the others. if someone knows how to fix that pls help me out again.

It looks like the vertex count is still a little off, causing that triangulated area (unless it also looks like that on the other side, but going the other way). One approach might be to bridge half the circumference and then bridge the rest in a second pass. This won't solve a count mismatch, but it will give you some control over where the triangulation occurs.


text:
Walk Cycle Loop at 0|0|0, not from A to B
For a propererly working walk cycle in UE4 I need my character not to move from A to B, it has to loop at 0|0|0. I use a bvh file as my walk animation, my character is imported from makehuman.
It should look like this in the end:
https://www.youtube.com/watch?v=6rLBCg_LAN4
(NSFW, video contains a nude character, but it is the best one I found to describe my problem/goal)
Thank you for your knowledge and time!


text:
How to get source code for border selection?
How to get source code for this function?
Border Select.
I want to look how bgl draw horizontal and vertical lines!
http://prntscr.com/g3m8i6


text:
Random objects to grid (Animation Nodes)
http://prntscr.com/ixcbym
How to assign, for some points of grid one object from group 'sec'. And for other points, other objects from the same group?

Please use the Imgur uploader to add images to your questions.

Starting from version 2.1, we have a Transform Mesh Node instead of the Replicate Mesh Node. First, we create a list with all possible meshes (One can use the Objects From Group Node to get all objects in a group and get the meshes from them.), then using the Random List node, we generate a list filled with the possible meshes, then meshes are transformed to the required location using the Transform Mesh Node. Which results in:

If it is not required that the output be a single mesh, one can instance a group of empty objects using the Object Instancer Node and then copy the meshes from a list filled with possible objects just as we did before. Which results in:

If you want to selectively add an object at some indices, then manual source object list creation is needed. For instance, if one wants to use the object Cube for the vertices at indices 0,1,...,9 and 40, 41,...50 and use the object Icosphere for the rest, then the object source list can be created as follows:

The Fill List Node can be used to fill a list with a certain number of objects, and the Combine Object List node can be used to combine multiple lists, so we can combine an object list filled with 10 Cube then another filled with 40 Icosphere and then another filled with 10 Cube. Then we can use the Fill List Node to fill the rest of the elements with Icosphere.

Thanks! But how to use some mesh instead of distribute Matrices?

I founded!  http://prntscr.com/ixsapl

How to set the position area for the location of an item?

@SergeyGolubev What do you mean by the "position area"?

What if I want the objects to be distributed according to the specified parameters. For example, in specific vertex groups or based on the values of some texture.

@SergeyGolubev You can ask another question for that.

Ок. Sorry for my eng). How set for grid points 1-10, 50-60 Cube, and for other points Cube.001?

Use the Fill List Node to create a list with 10  objects Cube and another one to create a list with 40 objects Cube.001, then use the Combine Lists Node to combine both lists, where the first list is the one with 10 objects, the second is the one with 40, the third the one with 10 again, then use the Fill List Node again to fill the rest with Cube.001. Do you want me to update the answer with screenshot or do you understand it as is?

If it does not make it difficult, throw off the screen

@SergeyGolubev Edited the answer with an example.

Thank you. And how to control the arrangement of elements, at the expense of vertex group?
And one more question. How to set colors to elements, so that they would change depending on how close to a specific element the controller is. For example empty

@SergeyGolubev You are getting into completely different questions. Ask separate questions for those and I will answer them.

Ok, have done! And how to control the arrangement of elements, at the expense of vertex group?

@SergeyGolubev I can show you how to do that, but ask a separate question for that. Is there some reason why you unaccepted the answer?

Ok, i have done.

@SergeyGolubev Why did you unaccept the answer, you have to tell us what you want in order to edit the answers accordingly.

Thank you lobster. On this topic, I kind of got all the answers. Which were needed at the moment

@SergeyGolubev Well, then please accept the answer if it answers your question.

A List or a Switch can be considered

Object List from Group with an Element Selected. You can programmatically determine which index of the list shall be used to select the particular mesh data.

Mesh Data List.  Consider a Loop Subroutine to Create the List.

2 items example

I assume we are using different versions of BAN Blender Animation Nodes.
Please inspect and improve to your needs


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how to display some text in blender 3Dviewport?
How to display some text in blender 3Dviewport?
like screencast addon display pressed keys?

Why do you not want to use the screencast keys addon?

You can draw on the 3D viewport by registering a draw handler and using the bgl and blf modules.
Registering the draw handler is done via bpy.types.SpaceView3D.draw_handler_add(). Just browse through the bundled Blender add-ons to get lots of examples on how this is used in practice.

Due to some simple limitations, the screencast keys add-on was removed from blender builds, you can read about that here . It may be possible to find it somewhere in forums or on github as an addon you can install How do I display what keys I use?, but if that is not an option, you can use some separate software. See lists like http://www.lassanamagassa.com/2014/09/7-apps-that-display-real-time-keystrokes-on-a-windows-pc-screen/, or you might want to try this if your are on linux.


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Offset Animation (Animation Nodes 2.0)
Shift animation.
How to copy an animation from one object to another, and make a shift for each animation?

What do you mean by shift (spatial, temporal,...)? I don't think you can copy an AN to an object, but you can place several objects in a group and code an AN for the group. About the shift, it can be defined in a custom property of the objects and reached in AN using an expression node. If that can fit what you want and if you need more details I can write an answer with more details

You can get the Fcurves from the source object, and evaluate them with some frame offset fro some object. You can get the fcurves using the FCurves From Object Node, to identify what fcurve belong to what property, FCurve Info Node can be used where, for instance, the data path will be location for objects' location fcurve and the Array Index will be 0, 1, 2 for x, y, z respectively. Having identified the fcurves for the properties you want, for instance, locations. We can go ahead and evaluate them while setting some offset:

By viewing the results, we see that the object Cube.001 lags behind the source object Cube by 5 frames (The offset we set):

We can put that inside a loop to perform it for multiple object, where the offset will be a multiple of the index of the iteration:

Which results in:

Thanks! But what if i have some group objects. Every object have uniq position! What if i want that source animation start from uniq position every object in group. Every obj in group have uniq geomety. But what if i want that animation start from my selection set oj in group?

@SergeyGolubev Use the ID Keys option to store the initial location of each object, see this. Then instead of using the evaliated fcurves vector as the location of the objects, add it to the initial locations and output the result.


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How to get some value from user?
I write addon. And i am, like some user, want manualy change some value. As example, string, for renaming!
How to do it? Also how to draw panel for this?

Some thing like this maybe.
import bpy

from bpy.types import(
        Panel,
        Operator,
        PropertyGroup
        )

from bpy.props import(
        StringProperty,
        PointerProperty,
        FloatProperty
        )

class HelloWorldPanel(Panel):
    """Creates a Panel in the Scene properties window"""
    bl_label = "Hello World Panel"
    bl_idname = "OBJECT_PT_hello"
    bl_space_type = 'PROPERTIES'
    bl_region_type = 'WINDOW'
    bl_context = "scene"

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

        # you need to get your stored properties to draw them
        scene = context.scene.your_properties

        col = layout.column()
        col.prop(scene, "string")
        col = layout.column()
        col.prop(scene, "size")
        col = layout.column()
        col.operator("some.thing")

class Add_some_thing(Operator):

    bl_idname = "some.thing"
    bl_label = "Add object"
    bl_description = "some description"

    def execute(self, context):

        # you need to get your stored properties
        scene = context.scene.your_properties
        # you get some of your properties to use them
        string = scene.string
        size = scene.size

        # you do some thing to use your property with
        bpy.ops.mesh.primitive_cube_add()
        # you can change some of the added object props as the defined in the ui property
        context.active_object.name = string
        context.active_object.scale = [size, size, size]
        return {'FINISHED'}

# your properties here
class addon_Properties(PropertyGroup):

    string = StringProperty(
        name = "the name",
        description="name of the object to add",
        default = ""
        )
    size = FloatProperty(
        name = "size",
        description = "size of the object to add",
        default = 1.0,
        )

classes = (
    HelloWorldPanel,
    addon_Properties,
    Add_some_thing
    )

def register():

    for cls in classes:
        bpy.utils.register_class(cls)
    # you store your properties in the scene
    bpy.types.Scene.your_properties = PointerProperty(type=addon_Properties)

def unregister():
    for cls in classes:
        bpy.utils.unregister_class(cls)
    # you delete your properties
    del bpy.types.Scene.your_properties

if __name__ == "__main__":
    register()


text:
How to build your own preset(node) in Animation Nodes?
How to build your own preset(node) like spider generetor or procedural wire generator?

Have you looked at the docs?

No, I have not seen this. Thank you. But in this documentation about coding. Is it possible to do something like a grouping. As in the nodes of the material?


text:
Difficulty in particle animation
I am currently making an animation of a hand picking a pile of sand(beach sand) and i cant find a way to make the hand pick up the sand or make it interact with each other...any suggestions?.

Is the hand animated?

you need to make a particle physics simulation https://blenderartists.org/forum/showthread.php?204008-Particle-system-simulating-sand

You also want to enable collision for the hand.


text:
Blending mode material in Cycles
I'm looking for a blending mode effect for a material that works like blending modes in Photoshop and other editing programs - that means material affects everything behind with blending mode effect.

What do you mean by 'material mode effect'?

I mean that an object with material affects everything displayed behind it with blending mode, like multiply or overlay.

As far as I know this is not possible to achieve.

Renderers are coded to behave like materials in real world. They try to be physically correct.
Most of these effects you are describing are non-physical and cannot be achieved with real world materials. Some even don't conserve energy of light!
Only effect that can be done with materials is Multiply. An effect that can be done with lights would be Add.
This non-physically correct renderer can be surely made and programmed, but I don't know of any. I don't even know why anyone would have a need for something like that - what you want could be probably achieved in post-production using these blend modes on 2d layers.


text:
Export every object into separate files
I have a scene containing parts of a modular tileset to be used in the game.
I want to export every object into separate files, and in every file object is moved to default (0, 0, 0) position.
How can I do this?

What file format?

fbx file format

Here's a snippet of code that exports FBX.  I tested it briefly and it appears to work.  It just iterates the list of all objects, selects each one individually, and calls the FBX exporter on the selected object.
import bpy

def export_all_fbx(exportFolder):
    objects = bpy.data.objects
    for object in objects:
        bpy.ops.object.select_all(action='DESELECT')
        object.select_set(state=True)
        exportName = exportFolder + object.name + '.fbx'
        bpy.ops.export_scene.fbx(filepath=exportName, use_selection=True)

Example usage, shown here with a Windows-style path.  Note that a trailing slash of some kind must be included due to use of simple concatenation of path and filename.  Also note that backslashes must be escaped (doubled) but forward-slashes do not.  Give it the name of an existing, empty folder with the trailing slash included.
export_all_fbx('C:\\outputFolder\\')

object.select = True -------- This line of code is not supported in Blender 2.80 any more, use  object.select_set(state=True)  instead. The rest of the code still works great.

Can you help me please?
The script does basically nothing for me. At first I had a syntax error somehow, but a friend figured it out. Now no syntax error, but no .fbx files neither. Here is the current script:
import bpy
def export_all_fbx():
objects = bpy.data.objects
for object in objects:
bpy.ops.object.select_all(action='DESELECT')
object.select_set(state=True)
exportName = 'D:\Exported\' + object.name + '.fbx'
bpy.ops.export_scene.fbx(filepath=exportName, use_selection=True)

The best option would be to write a quick Python script.
Essentially, you'd use a for ... in loop to iterate over all the objects. In that loop, you'd call whatever exporter you're using to export each object. You'll have to do some research to find out how to call it from Python, but it should be pretty simple.
It would also be a good idea to add some checks within that loop to skip certain objects (like the camera, or any empties).
Without actually sitting down and writing it, I can't be sure, but I'd be surprised (shocked, even) if the whole script was more than 10 lines.

If you're not familiar with scripting in Blender, there are some good tutorials out there. It shouldn't be too complicated.

Does this script exist somewhere in the internet? I don't think there isn't, because making model for games is common.

I'm sure someone has written one, but it's such a small thing that either it's too small to be worth publishing on the internet, or they've built it up to the point that they can sell it somewhere else. Yes, it's common to make models for games, but it's not common that you need to export objects from the same scene into different files. Typically, you'd have each object in its own scene.


text:
Close hole in mesh without loop
I have modeled a plane and the problem is that the bottom of the wing is missing.

How do I fill this hole in the easiest way?

Select the same number of vertices from both sides, press W and choose Bridge Edge Loops.


text:
Use a higher resolution background image in an animation render
I have a image which has full HD resolution (1920x1080) and I want to use it as background for my animation without decreasing the resolution. My animation is in HD resolution (1280x720). The background is added using compositing with nodes. When I render the animation Blender cuts of the edges of my background image so that it fits the animation resolution.
Is there a way to keep the resolution of the background image but render the animation with another resolution and still have the whole background image in the final animation?

Add a Scale node ("Distort -> Scale") to your background image. Then set the space to "Render Size". Then select "Fit".


text:
Align eges to remove holes when using mirror modifier
When I am applying the mirror modifier to my mesh the bottom of the mesh gets a hole in it.

This is because the top edges is not aligned with the bottom edges.

The yellow edge is the bottom one and the white is the top one. Is there any way to align the two edges (and all the others)?

There are few things you can do.

Enable clipping in mirror modifier options, select all and move everything towards middle point until top and bottom edges will align.
Rotate the object on the Y axis to align all edges.
Select top and bottom edges and press S then X and 0 to align them on X axis.
With clipping enabled, move all closer to the middle until closer edge will stack to it's counterpart on the other side, select further edge and with proportional editing enabled, pull it closer to the middle point.

I tried your third alternative and it worked for me, thank you!

Fair warnings follow:
1 & 4: You will break any faces that have vertices closer to mirror axis than the ones you are fixing. If you can, under no circumstances select all but only the problematic parts.

You need to first have your 3D cursor snapped to object in object mode and set the pivot to 3D cursor.


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How to reassign the textures to my imported obj in blender?
Recently Ive downloaded my maximo character created from blender with animations but when i reimport it back in blender, it does not show the textures.
The animations for the character were fine but it is in white color. Can someone shade some light on how i can reassign back my texture maps in blender? I am using cycles render.

What's maximo? A Software?

OBJ files can contain your UV layout. So, providing you have made your UV layout on the character, just apply your texture maps and the projection to the corresponding UV. If you haven't made uv's, create them.


text:
Add background image to render
I have a blender project that renders a transparent background. I would like to add a background image when rendering.
I tried following this guide except for the part where they explain about the shadow. But my background image is not rendered.
I think the problem is in the Node Editor (where I cannot make a configuration like the one in the guide). This is what I did:

Added a background image

Switched to Node Editor following he guide instructions. But my Node Editor screen looks empty like this:

Can you help me obtain a background image on the final render?

In order to overlay any image over / behind a render you want to use compositing nodes, not material. See http://blender.stackexchange.com/questions/61013/why-is-the-node-editor-showing-different-kinds-of-nodes

maybe this help you https://www.youtube.com/watch?v=h--yT0d28XA

Basically you have to switch the Node Editor to Compositing Mode not materials as it currently is in your screenshot.


text:
Cell Fracture Hallow Shards
I was trying to make a rock-like texture for my mesh by using cell fracture, but every time I used the feature - the shards appeared hallow. Is there a procedure I missed; or is there something I need to do with this outer covering that normally appears after I apply the cell fracture?

Well, when I applied location, rotation, and scale - cell fracture worked perfectly. It was hard to find the answer via google lol.

For those wondering how the OP had applied location, rotation and scale, the below may help.
For applying location, rotation and scale or a combination of these three:

Make sure you are in object mode and not edit mode.
select the object you want to apply rotation, location and scale to.
press Ctrl + A. A menu will appear. There you can choose what you want to apply. You can apply any one or all three too.

Note: Another thing which can cause problems sometimes with addons is improper normals.
To make normals consistent:

Select the object and go into edit mode
press A to select everything
press Ctrl + N to make normals consistent

Can you add these to the original answer as a more general how to? Thanks.

...who is @Marain ?

Someone had asked how to apply location rotation scale. I think it was this Marain person seems like the comment is no longer there for some reason

@iKlsR I don't think I can as I never wrote the original answer. Seems like the OP answered his/her own question.


text:
Blender won't open my Template or Not let me edit it
So im new to Blender but all the templates I have downloaded work after I double click or open with blender.
But this one template for some reason wont show and wont let me edit it(link below) Strange is also that I can indeed render the animation ,ut why cant I edit it?
Link of template:https://www.youtube.com/watch?v=aQhFOy2Dt-s
This is what pops up in blender instead of a normal editing screen:

Try hitting Shift + F5 with your mouse over the area you would be expecting a different view.

Possible duplicate of The main header has disappeared

nope no f5 and shift with mouse hovering

nope nothing has worked

Following the picture below, in your scene, first click the button at the square labeled 1 and in the popup menu select 3D View. Then click, hold, and drag the grip at the square labeled 2 and drag up into the bar immediately above it to get rid of the extra toolbar.


text:
Replicating double-sided normals on a cube face, extruding causes inner faces
So I noticed this when I created a cube object, extruded one of the faces and it created an inner face in the inside. Which was weird because normally extruding would just moves the face-out and leaves the original vertices without face inside the cube.
So this is what got and see the inside face but also that original cube in the middle has two normals for one face.

I wondering how to replicate that (The double sided normals), literally, how did I do that? I know I must of hit something to do that since I retried it on another cube and the extrude behaves normally.

it's impossible to have two normals per face. (you can check out the documentation of how the mesh datablock is designed)
The only way you can get this situation is if you managed to duplicate the face. (Shift-D for example) So you do have two faces overlapping, facing in different directions. You can verify that by selecting one face and then moving it away, the other one will stay.
Of course I can't really tell what you did in that particular scene.

Upon further inspection, I might have created some weird hyper cube with the normal getting inverted. Thanks for the answer!


text:
Is there a way to set the direction of the sun light on an object (without rotations)?
Basically, I'm wondering if I can set the sun lamp's light direction towards a position, such as an object, with a simple command, rather than doing rotations with R which is hard to control.

One way to do this is with a Track To constraint:

Select the sun lamp
⇧ Shift select the object you wish to point the lamp at
Press ⎈ CtrlT and choose Track To Constraint.

The sun lamp will now always "look" at that object, so you can move it around with G for easy adjustment.
You can adjust the constraint (or remove it) in the Constraints tab of the Properties area when the sun lamp is active:

Although, this works very well for objects, you won't be able to set the direction to a position in 3D space i.e the location of the 3d cursor pointing to that position. Is there a way to do that? Otherwise I'm happy to accept this as the answer.

@ManWithAComputor I'm not aware of anything exactly like that, however should be possible to create a custom operator which does this (using python). As for something native, you can do some stuff with making the lamp the active camera (Ctrl Numpad 0) and using Ctrl Alt Numpad 0 (align camera to view), which when combined with view manipulation shortcuts (e.g. Numpad .) can sort of do this. Not exactly "fast" though. In fact, tracking the sun to an empty and snapping said empty to the cursor location (Shift S) is likely faster.

@ManWithAComputer, You could use an Empty (an invisible object) and track to that.


text:
Join two meshes at the intersection within edit mode
Problem
Curiosity question here, I have the problem where I have created two meshes have inside the same object (so we are inside edit mode) with the purpose of combining both of them as one joined mesh
For example, as illustrated here:

Question
In the picture, I have two mesh object that are disjoint, One 'large shell' mesh and rectangular square mesh. I wish to join these two faces as I showed in the picture and then clean up the unneeded vertices. Is there a way to do this within edit mode?
Cheers

Being both separate meshes in the same object, you could manually edit faces until you get what you want. Otherwise you could separate one of the two meshes in a object of its own, then use booleans to create a "union". But be prepared to correct issues in topology. I would do the first way.

Press "SPACE", select search, type "intersect".
Click "Intersect (Boolean)".
Select "Union" from the dropdown menu.
Done.

I didn't know about this, but it always gives me a "intersection not found error"? even on very simple tests

In that case you will have to post the .blend for us to figure it out.

Thank you, so much for this. Note, if you do not see this tool upgrade your blender to at least 2.77. I was using blender 2.75 at the time when I asked the question and it doesn't have it.

@AdamTM see https://blender.stackexchange.com/questions/83022/same-mesh-boolean-intersection-gives-an-error

select two mesh you want to join in object mode. Then press Ctrl+J.

OP already has one object, so nothing to join. They wanted to intersect meshes and create one mesh of them without leaving Edit mode (like Boolean). Thankfully Knife Boolean was already coded for that


text:
How to make a dodecahedron?
I would really like some help to make a dodecahedron! That means i would like to make a "ball" form made entirely of pentagons.


text:
Blender crashes when adding two more faces to the same mesh with python
I tried to add two faces to the same mesh containing nothing with obj.data.from_pydata([], [], faces) ,  obj.data.polygons[-1].vertices or bme.faces.new(verts).
They were all success when adding the first face, but blender all crashed when adding the second face.
I even tried different ways when adding the two faces, but blender still crashed.
However, It's work when adding the two faces to different meshes.
I have no idea why blender crashes in this situation and how I can fix it.
By the way, the reason why I need to do that is because I want to use bpy.ops.mesh.intersect(mode='SELECT_UNSELECT', use_separate=True, threshold=1e-06) to cut out the intersection of two faces.
The two faces can be in the same meshes or not, depending on what bpy.ops.mesh.intersect() needs
Please tell me if you have any good suggestion, and thank you in advance.

A face is defined by three or more vertices, only the index number of the vertex is known to the face. Without vertices it will be reading random data looking for the vertex locations, which would be the cause of the crash. You will need to position the vertices where you want the cut to happen so define the vertex positions and then use them to make the faces.

I had added 4 vertices and known the index and position of each of them before I added the second face. I followed this method to add the first face and it worked, while it didn't work when adding the second face.


text:
How to get the total number of vertice, edge and face in camera view with Python?
I know how to get these information in the whole scene with Python, but now I want to get them only in camera view.
Or can blender export any documents including these information ?

what about objects that are only partially in view, are you going to only count the visible part?

The code in this link calculates the UV coordinates from the camera 3D projection. You can use the same principle to check vertices that are in the camera field (in field if all co between 0 and 1). https://blender.stackexchange.com/questions/76774/projecting-multiple-images-onto-an-object-with-uv-project-modifiers/77108#77108

@David Only visible parts, since I want to do something with rendering.

@lemon Thank you very much. Now I have to read it for a while to understand it,  but it looks like what I want.

@lemon What does "in field if all co between 0 and 1" mean? After reading these principles, I am confuse what I can do with these principles? First, do I need to project something onto something? Second, in my project, the camera has been determined, I can't change it. So do I still can use these principles?

Following your question in the comments below your question, I give here a partial answer and some guidelines (but the complete code is too long to do for me).
So just some code snippets:
CameraSetting class: allow to calculate the projection of a vertex in the camera/view given a mesh object. This code does the same as bpy_extras.object_utils.world_to_camera_view(scene, cam, co) but it calculates many things once instead of doing it for each 'co'. See here.
CountForObject function: provide a simple calculation of the vertices included in the view of a camera.
Note also that you can optimize the calculation by checking the bounding box of the objects before calculating all their vertices projections.
Hope it can help (the code contains additional comments):
import bpy
import time
from mathutils import Vector
from operator import itemgetter

#Used to store information related to a camera setting for a given object
class CameraSetting:
    def __init__( self, scene, camera, obj ):
        self.camera = camera
        #Z axis of the camera translate in world (Z axis is opposite to view)
        self.zInWorld = Vector( (0, 0, 1) )
        self.zInWorld.rotate( self.camera.matrix_world.to_euler() )
        #Camera parameters
        #Matrix to convert from object coordinate to camera coordinates
        self.toCameraMatrix = camera.matrix_world.inverted() * obj.matrix_world
        #The frame is composed of the coordinates in the camera view
        frame = [v / v.z for v in camera.data.view_frame(scene=scene)]
        #Get the X, Y corners
        self.minX = min( v.x for v in frame )
        self.maxX = max( v.x for v in frame )
        self.minY = min( v.y for v in frame )
        self.maxY = max( v.y for v in frame )
        #Precalculations to avoid to repeat them when applied to the model
        self.deltaX = self.maxX - self.minX
        self.deltaY = self.maxY - self.minY
        self.offsetX = self.minX / self.deltaX
        self.offsetY = self.minY / self.deltaY

    #Calculate projected coordinateds from the object coordinates
    def CalcProjected( self, objCo ):
        #Object coordinate in camera view
        camCo = self.toCameraMatrix * objCo
        #Z is "inverted" as camera view is pointing to -Z of the camera
        z = -camCo.z
        try:
            #Translates x and y to projected coordinates
            x = (camCo.x / (self.deltaX * z)) - self.offsetX
            y = (camCo.y / (self.deltaY * z)) - self.offsetY
            return x, y, z
        except:
            #In case Z is zero
            return 0.5, 0.5, 0

def CountForObject( scene, obj, cam ):
    matrix_world = obj.matrix_world
    rotation_world = matrix_world.to_euler()

    vertices = obj.data.vertices
    camSetting = CameraSetting( scene, cam, obj )

    vertexCount = 0
    #Go through all polygons
    for v in obj.data.vertices:
        x, y, z = camSetting.CalcProjected( v.co )

        if 0 <= x <= 1 and 0 <= y <= 1 and z >= 0:
            vertexCount += 1

        #z can be tested to see if its correspond to the camera clipping (cam.data.clip_start/cam.data.clip_end)
        #This calculation allows to check x and y
        #x and y are between 0 and 1 if in the camera field (because CalcProjected do so)
        #From that you can consider that all edges and faces which have a good vertex are in field too
        #But for the remaining edges you'll need to check if the corresponding vertices projection intersects the (0,0) to (1,1) square
        #Then consider the polygons that correspond to these edges to count them two

    print( vertexCount )

scene = bpy.context.scene
obj = bpy.data.objects['Cube']
cam = bpy.data.objects['Camera']

CountForObject( scene, obj, cam )

Thanks for your help, you do gave me a big favor!!! Now I can get what I want.


text:
Change value of material emission strength from Python console or script
I need to programatically modify the value of Material > Surface(Emission) > Strength

When I change this value manually the output is: bpy.context.space_data.context = 'DATA'
bpy.data.node_groups["Shader Nodetree"].nodes["Emission"].inputs[1].default_value = 1.2

But this command produces an error on the console:
>>> bpy.data.node_groups["Shader Nodetree"].nodes["Emission"].inputs[1].default_value = 2
Traceback (most recent call last):
  File "<blender_console>", line 1, in <module>
KeyError: 'bpy_prop_collection[key]: key "Shader Nodetree" not found'

I also tried accessing a surface attribute of the material but this doesn't work either:
>>> bpy.data.materials['light_emit.002'].surface
Traceback (most recent call last):
  File "<blender_console>", line 1, in <module>
AttributeError: 'Material' object has no attribute 'surface'

Besides, where can I find the api reference to try solve these problems by myself in the future?

Found a solution:
bpy.data.materials['material_name'].node_tree.nodes["Emission"].inputs[1].default_value = 3 #or any other value

Thanks to this reference

What would the equivalent be in Blender 2.8+? I am getting key "Emission" not found'

OK, ^ solved with https://blender.stackexchange.com/questions/5668/add-nodes-to-material-with-python


text:
Blender game engine modification of material value node during game
I need to modify the value of a value node with a script. How can I do that?
Or is there another strategy to modify texturing in a game?
I want something like the Attribute node in Cycles.

I solve my problems by write my own shaders.
1) create a material
2) Create a vertex shader

uniform float variable_name;
void main()
{
    vec4 co = gl_ModelViewMatrix * gl_Vertex;
    gl_Position = gl_ProjectionMatrix * co;
}

3) Create a fragment shader

void main(void)
{
  gl_FragColor = vec4(1.0,0,0,1); // RGBA
}

4) load it
#vertex
with open("__path__.vert") as a:
    vertex_shader_code = a.read()

#fragment
with open("__path__.frag") as a:
    frag_shader_code = a.read()

import bge
own = bge.logic.getCurrentController().owner
m = obj.meshes[0]
shader = m.materials[0].getShader()
shader.setSource(vertex_shader_code, frag_shader_code, 1)

5) pass variable to GPU over uniform value.
shader.setUniform1f("variable_name", 10)

You can use the vertex color (if the property should be shared across all objects with that material), giving you access to three floats.
Or you can use object color, giving you another three floats. This one is per-object, so it generally a lot more useful, though it does require the creation of another material to use as input (shadeless with object color ticked).
The advantage of these two methods are that you do not need to write your own GLSL code so the build in real-time shadows still work. (And you don't need to know GLSL)


text:
How to run a python script external to Blender to run bpy commands in Blender'spython console
Platform = Ubuntu Linux 64 bit, Blender 2.77a
When creating models using bpy-based python scripting, there many times I need to type in the same code in Blender's python console; every time I invoke a new blender session.
For example if something is wrong with objects, I type the following:
for object in bpy.data.object:
    print(object.name + " is at location " + str(object.location))

I would like to put this in an xxx.py file I create in a documents folder so when I need to execute it in the Blender python console at each Blender session, all I would need to do is run the .py file ; this will save a lot of repetitive typing.
How do I do this?
Sam

Note, Blender comes with a template to do just this: Text Editor -> Templates -> Python -> Script Stub

This is the equivalent to running the script directly, referencing a scripts path from a 2 line text-block.
filename = "/full/path/to/myscript.py"
exec(compile(open(filename).read(), filename, 'exec'))

You might want to reference a script relative to the blend file.
import bpy
filepath = bpy.path.abspath("//myscript.py")
exec(compile(open(filepath).read(), filepath, 'exec'))

Thank you so much Smart Gnan Online!!  This is a great forum!

More concise exec invocation: exec(open(filepath).read())

Using blender's text editor you can open a script file to read and edit it. The text editor also has a "Run Script" button to easily run the script you are editing.
An open text file can also be run within the python console with
exec(compile(bpy.data.texts['Text'].as_string(), 'textblock', 'exec'))

this has an advantage when debugging as the variables in the script will remain available in the console after it has been run.
Some time back I started using an addon posted on blender artists that adds a menu to the console which lets you run any open text block in blender's python console. You gave me an idea to expand it a bit by adding another menu made from script files in a directory, the addon will now also list the files within a specific directory which will be loaded and run when chosen. You can download the updated addon here.

thanks for sharing that Idea! It fills in the gap between developing a full blown operator and just an expression typed into the console. Perfect for those quick-n-dirty snippets and stuff which lives just for some weeks, during the work on one scene, but is not worth elaborating into a full-blown piece of code

Here are two variations on the answers given by Patan and sambler that some may prefer.
Variant of Sambler's answer
If you care about in-Python-console logging, but not availability/persistence of variables, then this approach is a slightly simpler alternative to sambler's answer: (run this in the Python console)
bpy.data.texts["NameOfScript"].as_module()

Variant of Patam's answer
If you care about in-Python-console logging, but not availability/persistence of variables, then this approach is an alternative to Patam's answer: (use this as your in-Blender "launcher" script)
import sys
import bpy

# this code block will redirect calls to print() to show up in the Python-console panel
class StdOutOverride:
    def write(self, text):
        sys.__stdout__.write(text) # also send to standard-output (can comment this out)
        if text != '\n': # ignore extra stdout.write('\n') call at end of each print()
            for line in text.replace('\t', '    ').split('\n'):
                for area in bpy.context.screen.areas:
                    if area.type == 'CONSOLE':
                        with bpy.context.temp_override(area=area):
                            bpy.ops.console.scrollback_append(text=line, type='OUTPUT')
sys.stdout = StdOutOverride()

filename = "/full/path/to/myscript.py"
exec(compile(open(filename).read(), filename, 'exec'))

I prefer this last approach myself, as it lets you get logging in the Python console, while still being able to use the convenient "Play" button in the script-panel's toolbar. (and this way there's less conflict, in case variable-names in the script overlap with whatever code I may be iterating on in the Python console)

This is great! I love not having to look at the console output in a separate window.  But the feedback doesn't show up in the python console until the script has finished running, which makes it less useful for long scripts (e.g. looping through a series of renders).  I was able to get more updates using bpy.ops.wm.redraw_timer(type='DRAW_WIN_SWAP', iterations=1) but that comes with performance issues and throws a warning each update.  Are there any other methods to updating the python console in ~realtime?


text:
Merging two objects with respect to face
I'm new enough to Blender to not really know how to ask this question, so bear with me. I thought I would do something "easy" - I have the interior dimensions of a box, so I started by making two of the walls and lining them up at the corner with a wide face of one against the narrow face of another:

I first tried using a Boolean Union to merge these into one object, but by the time I get to the third wall, the walls start disappearing. I also think that the union left a face inside the two walls, where I was hoping to get one solid object (mesh?).
As a second attempt I tried to use Join to merge them, but again I get faces left over inside the new object and when I used Boolean Union on the joined object later (with some other object) some of the walls would disappear.
So the question is, is there a way to align two objects as I have done and create one single solid object without all the leftover interior geometry (faces)? Hope that makes sense.


text:
What is the definition of "ples"
What does ples mean? The editors section, on the picture attached, has an arrow that points to the word ples. I would like to know what it means.

I guess that is pies (pie menus), but it would have helped to know WHERE you took that image, isn't it?

@m.ardito it comes from https://www.blender.org/manual/interface/introduction.html#screen-elements and that image should be fixed so it doesn't like like pLes :)

I'm voting to close this question as off-topic because it's a problem with the typographic choices of the person who wrote that manual page. it doesn't say ples it says pies

i'll be reporting this to the guy(s) in charge @Daniel, thanks for the question.

in the meantime: does this diagram help?


text:
Can't bake anymore
I know this has already been asked before, I checked almost every question I found from Stack-exchange to CGcookie and blenderartists  and other forums , I followed every instruction step by step ... yet none of the answers worked.

It's been an hour I'm trying to bake this thing and I have no idea what's wrong... it used to work, I already did it before but it seems blender has started to hate me...
I'm about to throw my computer out of the window...
Do I have to re-instal blender?

What option did you change before being able to bake?

only the numpad emulator... I tried to reset it  with load factory settings and it didn't work .....

It looks like you use Blender Internal. It could be a bug (somewhat long ago it occured once to me and didn't ever become clear what was wrong) but to check that please upload the file or a part of the problem mesh (delete anything else) and comment with a link / edit a question. Also what bake are you trying to do ?

I'm trying to bake a multi-resolution  model   to a low poly one, though can't uppload a file , it is too heavy even though I have amputated parts of the model but it excess the limit by 40 MiB

The error can happen when Blender looses association with the texture set. In my case I detached the image texture in the compositor and then then reloaded and re-connected the node. In theory I changed nothing, but the refresh worked for me. Hope it does for you...

I don't know, it seems to work with any other model but this.... at this point I'm just sculpting it again...

Did you try importing it into another project / file and baking from there ?

yes, I tried it....


text:
Multiple bakes are not working
I'm stuck with a situation in my animation for fluid effect. The first time i baked the scene to check rhe results of how things will be. Then I added another object as obstacle in my domain and baked again. It shows im progress bar that its baking but the result showed rhe previous bake outcome. I removed the baked files from cache and again baked again same results. Closed the blender, restarted and baked but results were still the same as old bake. I just got too frustrated now, can anybody help pls ?
Thanks.

Not much to go on here. If you would post the blend file, it should be easy to find what is wrong. In general, the more information you give, the more likely you are to get an answer.

Check the relative path and absolut path of the bake path.
check the scale of the baking domain is 1.0 in all the directions.


text:
Fluid flow when x,y,z are at 0
I'm creating a small video in which I have a glass and fluid as water to flow into the glass.
Now in my domain I do get a continuous fluid flow if I change the x,y,z direction coordinates under the domain but I get  fluid flow like water drops when x,y,z are 0.
The scene needs the flow of water directly over the glass but I don't get continuous smooth flow.
Any help would be appreciated here.
Regard,

The x,y,z values in the fluid domain settings define the effect of gravity on the simulation. Values of 0,0,0 mean the fluid is floating in space. A Z value of -9.81 is used to approximate earths gravity.
You have a couple of options for the object used as the starting point of the fluid, setting the type to fluid gives you a single "blob" of fluid with a total volume equal to the size of the mesh while a type of inflow will give you a constant flow of fluid coming in. The initial velocity here defines the direction the fluid first moves, a negative z value will have it fall straight down, while changing the x and y values can get it to flow diagonally into your cup.

Thanks Sambler. The -ve z value is working. Thanks alot for your help.


text:
Problem with anchors in blend4web
I have a question
I try to put a custom html object on an anchors for a empty object.
problem is when I try this on an bundled style project it works fine no problem
But in a non bundled external project as soon as I have a HTML element with the good ID the scene stop loading.
Any idea why? what am I missing here?
here is the code for the bundled project :
"use strict"

// register the application module
b4w.register("test", function(exports, require) {

// import modules used by the app
var m_app       = require("app");
var m_data      = require("data");

/**
 * export the method to initialize the app (called at the bottom of this file)
 */
exports.init = function() {
    m_app.init({
        canvas_container_id: "main_canvas_container",
        callback: init_cb,
        show_fps: true,
        console_verbose: true,
        autoresize: true
    });
}

/**
 * callback executed when the app is initialized
 */
function init_cb(canvas_elem, success) {

    if (!success) {
        console.log("b4w init failure");
        return;
    }

    // ignore right-click on the canvas element
    canvas_elem.oncontextmenu = function(e) {
        e.preventDefault();
        e.stopPropagation();
        return false;
    };

    load();
}

/**
 * load the scene data
 */
function load() {

        var torus_text = document.createElement("span");
    torus_text.id = "buttonPlay";
    torus_text.style.position = "absolute";
    torus_text.style.padding = "5px";
    torus_text.style.visibility = "hidden";
        var torus_img = document.createElement("img");
    torus_img.src = "Images/B_play.png";
    torus_img.atl = "the button";
    torus_img.height = "42";
    torus_img.width = "75";
    torus_text.appendChild(torus_img);

    document.body.appendChild(torus_text);

    m_data.load("test.json", load_cb);
}

/**
 * callback executed when the scene is loaded
 */
function load_cb(data_id) {
    m_app.enable_camera_controls();

    // place your code here

}

});

// import the app module and start the app by calling the init method
b4w.require("test").init();

and the one for the non bundled external project :
"use strict"

// register the application module
b4w.register("JumboConf", function(exports, require) {

// import modules used by the app
var m_app       = require("app");
var m_cfg       = require("config");
var m_data      = require("data");
var m_preloader = require("preloader");
var m_ver       = require("version");

// detect application mode
var DEBUG = (m_ver.type() == "DEBUG");

// automatically detect assets path
var APP_ASSETS_PATH = m_cfg.get_std_assets_path() + "JumboConf/";

and the one for the non bundled external project :
"use strict"

// register the application module
b4w.register("JumboConf", function(exports, require) {

// import modules used by the app
var m_app       = require("app");
var m_cfg       = require("config");
var m_data      = require("data");
var m_preloader = require("preloader");
var m_ver       = require("version");

// detect application mode
var DEBUG = (m_ver.type() == "DEBUG");

// automatically detect assets path
var APP_ASSETS_PATH = m_cfg.get_std_assets_path() + "JumboConf/";

/**
 * export the method to initialize the app (called at the bottom of this file)
 */
exports.init = function() {
    m_app.init({
        canvas_container_id: "main_canvas_container",
        callback: init_cb,
        show_fps: DEBUG,
        console_verbose: DEBUG,
        autoresize: true
    });
}

/**My function
*/
function CreateBt(id, source, hgt, wht, altern) {

    var btText = document.createElement("div");
        btText.id = id;
        btText.style.position = "absolute";
        btText.style.padding = "5px";
    btText.style.visibility = "hidden";
    var btImage = document.createElement("img");
    btImage.src = "/Images/"+source;
    btImage.atl = altern;
    btImage.height = hgt;
    btImage.width = wht;
    btText.appendChild(btImage);
    document.body.appendChild(btText);

}

function IdeCration(){
    CreateBt("RotBts","Bt_choix.png","42","72","bt_play.png");
}

/**
 * callback executed when the app is initialized
 */
function init_cb(canvas_elem, success) {

    if (!success) {
        console.log("b4w init failure");
        return;
    }

    m_preloader.create_preloader();

    // ignore right-click on the canvas element
    canvas_elem.oncontextmenu = function(e) {
        e.preventDefault();
        e.stopPropagation();
        return false;
    };

    load();
}

/**
 * load the scene data
 */
function load() {
    IdeCration();
    m_data.load(APP_ASSETS_PATH + "JumboConf.json", load_cb, preloader_cb);

}

/**
 * update the app's preloader
 */
function preloader_cb(percentage) {
    m_preloader.update_preloader(percentage);
}

/**
 * callback executed when the scene data is loaded
 */
function load_cb(data_id, success) {

    if (!success) {
        console.log("b4w load failure");
        return;
    }

    m_app.enable_camera_controls();

    // place your code here

}

});

// import the app module and start the app by calling the init method
b4w.require("JumboConf").init();

hey, you might want to repeat your question on Blend4Web forums


text:
Camera settings to imitate Samsung Note 9
Hello stackexchange community
I wish you all a happy holiday season
I would like to know what values , for my mobile phone "Samsung Note 9", i must set in Blender 2.8
Specifications i know
Sensor Size: 1/2.55; Wide angle: 26mm; Sensor ratio: 4:3; field of view: 77°
the Crop factor I don't know
My settings:
for lens:
Type: Pespective; Focal Length: 26mm;
for camera: Sensor Fit: Auto; Sensor Width: 26mm;
(Here I have my problems, If i choose 4:3 inches, then the frame is too small.)
Which settings are still necessary or have to be set exactly to simulate the camera?
Thank you for your answers in advance
CloneBorg

4:3 is the aspect ratio so not about inches buddy. Best way is to take a picture of something pretty simple, replicate it in Blender, set the camera and "get rid" of all the differences. Also the focal of 26mm seems to be not right as a perspective settings of Samsung.

Thanks a lot for the hint. 1. I put a box right in front of the camera, so that the right and left sides fit exactly into the picture from the Kamera (Display).
2. Then I measured the distance from the camera to the carton.
3. In Blender I adopted exactly the measurements of the cardboard and the distance of the camera.
4. I set the focal lens to 26mm.
5. Then I used the slider from the sensor width, until the box fits into the frame from the camera picture.
Now I've come close to what I wanted.

Happy to hear that Buddy ;).


text:
How can I create irregularly apportioned vertices in regularly distributed vertices in a loop, without changing the loop?
As already mentioned above, I would like to distribute all vertices evenly in a loop. The loop or curve should not be changed; is there method that does this for me automatically.

as you can see, the vertices are distributed irregularly.
now I want to distribute the vertices evenly, without changing the curve or loop

The LoopTools add-on (included with Blender) has a space function which I think will do what you need.

Quick reaction Lewis, you're absolutely right, that's exactly what I needed. Many thanks!

I'm not sure you will get a 100% semi-circle but the result will be pretty good if you use the LoopTools addon. Activate it, then press W > LoopTools > Space to make the space between each vertex equivalent. Then again press W > LoopTools and Relax. Note that you can play with the parameters on the bottom of the Tools panel on the left of the 3D View (displayed with T)

Also to you, thank's a lot much for the detailed information. A little supplement, if the Loop Tool is activated on Blender 2.8 (2019-01-10) then you need only a right-click, to choose what you want.

The shipped Loop Tools add-on > Space option may do exactly what you want..

It can make a cubic interpolation from existing irregular points, resulting in a smooth curve fit. You can set it to 'Linear'..

.. which will be more faithful to the jumps in tangent directions created by gaps between vertices before the operation.

Thanks for the answer, the Loop Tool has brought me forward. Exactly the space function has brought me further. It was nice that you answered me so quickly, thanks again.


text:
Blender noise during paint in Texture paint mode
I have weird problem. During paint in texture paint mode after paint the color is not filled but have any "noise". Like on the image:

@MrZak Yes, I do. If You could make answer then I will mark it.Thanks.

In texture painting, brush can have a texture assigned to it as a pattern. When it is, the pattern will be applied to every stroke done with the brush (appearence will depend on settings of the brush mapping etc.):

See more about how to assign a texture to the brush and paint with it.
If you want to continue drawing with solid color, unlink that texture in brush settings by pressing X button next to its name. For more about that refer to Users (Sharing) and Removing data-blocks in manual.

authors: Макс Кушнаренко


text:
Mirror vertex selection
Let's say I have selected some vertexes:

How do I mirror this selection (in x axis) so I can select the other side (same vertices assuming my mesh is symmetric)
I just want to select the other side not do any operations.

this is not answer, yes
its mirror not for selected dots

Choose Mirror from the Select menu and check the Extend option.

I can't find the extend option, selecting mirror in select menu attempts to mirror and fails with error "0 vertices mirrored"

@Arijoon Extend option is in Last Operator panel, either open Toolshelf or press F6. Although it should work without that the option - it will only add mirrored selection to your original one. Check that you don't use Mirror modifier

Does Blender 2.8 still have this feature?

I don't see that in blender 2.8

I see it in 2.82(.7)a  if you select and then click Select>'Mirror Select' after using symmetric sculpting it says something like "Warning: 0 vertices mirrored, 5139 failed" so it is not able to understand exactly where it's partner vertices are or edges or faces. So the real answer is "no it does not" create a double selection brush (pressing 'c' for instance) as you might expect or hope. Another one for the suggestion box. I guess you'd have to use the mirror modifier route to do that but there should be a sculpt brush to do what you want if that be the case.

Go to edit mode
Go under the modifiers tab and add modifier. Look for the Mirror option under generate.
Ensure that the X-axis is checked. Click on the vertices buttons under the Mirror modifier and you should be able to see it in your 3D view.
To apply the mirrored vertices click Apply.

This doesn't answer the OP's question


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Fbx exported file is different to .blend when imported in Unity
I encountered a weird issue today. When I exported my model as fbx and imported it, I noticed the meshes were different to the .blend import. For example there was a hole in my character's head. I went back to check normal and they were all fine. How do I check what is causing this issue and results in different meshes from .blend and .fbx formats?
It is also interesting to note fbx actually keeps all the animations however .blend removed a lot of small animations from my model. Is this normal?


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displaying a URL on a surface
I have a URL that may be an embedded video or a series of web animations(sort of like a slideshow) on a webpage and I am wondering if it's possible to display that within blender (e.g. on a panel or face of a cube)? Basically would it be possible to display a website within blender?

It would be pretty easy to take an image/video of the website and apply that to an object as a texture, but it won't be interactive. Will such an approach work for you?

This is not possible in a direct and interactive way.
Firstly, Blender can connect to a URL and retrieve the raw html in text form. However, Blender cannot render this html into a visual format and then use it as an image texture. There may be online web services that render an html document into an image (like a screenshot), but Blender would then have to download that image before importing and applying it as a texture.
Secondly, images or videos that are sourced through a URL cannot be directly set as the texture source for a material. The files would have to be downloaded via python and then loaded via a local filepath value. This is possible but would require some steps with scripting, and would not be immediately interactive.
The same goes for a video file or a sequence of images. They would all have to be downloaded from the remote URL location before being able to be loaded into blender as textures.

You should be able to use something like CEF Python, project that should allow you to embed the Chrome browser in other applications.
There is currently still an open issue that I think may need you to do some extra work to get it going, but with this you should be able to embed a browser to show web pages inside Blender in panels.
You'll have to go through the documentation to find out how to do it, but with the off-screen web-page rendering capability it should be possible to get this working.


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How to return to the default view that you see when blender starts?
I was wondering if anyone knew how to reset the viewing angle to what it was at the startup. I just want to reset it to that view, not reload startup file or load factory settings or anything. I want to have this viewpoint
but still have all the work that I did.

Can I reformulate this question : how to setup a camera so that it is placed at the exact same view as the 3D viewport view ?

Welcome to BSE, please edit your question to fit the new reformulated question

@lemon That's a good thought, but I'd wait for more information. The OP might not be wanting to move the camera object, just the viewport view.

@Matt, yes. This was a connected question but not the same.

The following answer assumes that the object(s)  to be displayed are at the center of the scene (that is, X = Y = Z = 0.), and make certain that the 3D cursor is positioned at the same place. To achieve the same point of view as if the camera were in a similar position for a scene, make certain the 3D viewport is in object mode, that the camera is the active object, and that the pivot point is defined to be the 3D cursor. Then open the tool shelf (N key). In the X, Y, and Z co-ordinates of the selected camera, and in the boxes for the rotation of the object, enter the values shown in the red box in the image below:
[
If the camera needs to be moved to a different location, in the X, Y, and Z boxes for the camera, multiply the values in each box by the same scalar number, so that, for example, if you needed the camera to be 4.3 times further away in order to see the whole object, you would multiply the values for X, Y, and Z each by 4.3. The boxes take numerical expressions, so you can do this by selecting each box in turn, selecting the value, and adding the string * 4 . 3 Enter. To keep the view the same, all three values will need to be multiplied by the same scalar value
If only part of the object is not visible, because some of it is cut off, change the value in the box next to the "end" button in the green box in the illustration. [NOTE: for purposes of economy, I have reordered the panels in the Properties shelf panel.] This will increase the depth of the field of view.

As per your comment on your question, to set the camera to the same view:
Press Ctrl + Alt + Numpad 0

thanks. That move the cam at the good position. But is there a way to modify also the render size so that it fits the viewport ? But I will set that as a new question...

Start a new file, save it as camerapos.blend, then open your main blend file and append the camera from the camerapos.blend file into your main scene and make it the main camera.