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How to create a bottom for this rock to make it a whole mesh?

I've tried boolean with union, but that copies the whole object and when I go to retexture the copy, it turns out wrong. I need to create a bottom so I can shape it and then copy the rock texture to the bottom so the rock appears whole.

You could copy some of your rock mesh (selection with inner region or circle select...) and orient it, so that you don't need to fill a large hole, but you have a gap between your rock mesh and that patch.
Then you could fill this gap with methods like shortest path select (hold ctrl while selecting) the gaps borders for short lengths of the gap and then fill faces (with F).
The gap filling result will be nicest if in advance to filling you extrude the parts of the gap closer to each other in multiple iterations(Then you have quads in most of the gap region)


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Imported Obj "Tears" visually but not in the mesh
Been having an issue with certain objects modelled in Sketchup and exported as Obj into Blender. On import faces occasionally have this bizarre visual tear that I cannot seem to get rid of.

A Redditor suggested I turn on autosmoothing (it is already on) and clear the custom normals. This instantly fixes the look of the model - until you go to texture paint, and which case the problem endures (this look slightly different because they were taken on several models wherein I tried to fix the problem by re-exporting the sketchup original with minor changes to the model).
If you go to paint, the 'tear' remains and seems to have carried over into the UV Unwrap (which I make AFTER clearing the custom normals)

Furthermore, this visual tear seems unrelated to edges or faces:

What's going on and is there any way I can fix it?

Hi, please consider posting the images inline in the future. It makes it faster and easier to understand your issue for all the good people who might be willing to help you.

For future reference could you explain what doing that looks like?

source: Stack Exchange

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

sort: votes


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Blender Vertices Merge Problem
I am a using Blender version 2.82 on Windows 10. I'm following this tutorial on
YouTube https://www.youtube.com/watch?v=zHv4VDoCwYc at 28:00 where he merges 2 vertices. However when I try it, it turns out like this:

It looks as if you made an edge.

Hi. Please make the title of your question specific to the problem you are having and not just the general topic. Thanks.

He is definitely doing it right in the tutorial so the problem lies somewhere in the part you have not revealed any information about - in something that you did differently. The thing to do here would be to redo it all again until it works carefully tracking and keeping all your actions in mind. This is how tutorials should usually be approached.
I guess, you may have double geometry and when you select the vertices, some overlapping vertices remain unselected. You could try to redo the whole part from start or select all and merge vertices by distance first.

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


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How to fix streched texture areas after unwraping UVs?
I just UV unwrapped my first model and I have a problem with the texture. The UV unwrap looks fine (all blue), but in the 3d model it's not that good. The texture stretches and I'm not sure why. I'm using Blender 2.80.

It's probably because of modifiers you have in stack on the object. If there are faces with more than 5 sides they might cause deformations after e.g. subdivision. Hard to say without more information about mesh topology and modifiers used

i only use a subdivision modifier,

Ok, i found the solution by myself, i added a loop cut (ctrl + r) where the texture stretches.


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Why can't I see an outline around selected objects?
I think I pressed something I didn't know and now object that I want to select won't get highlighted. The outline thing when you select an object doesn't appear, I still can move it around but that orange thing doesn't appear.

Perhaps add a image of your viewport display to make your question more clear?

It sound like you disabled Show Overlays. You can activate the overlays by clicking the Show Overlays button, usually found in the top right corner.

There is way of making things unselectable. You can use it for making sure you don't move stuff unintentionally. It is hidden in the top right of the screen under a little filter icon, looks like a funnel.
click on it and there is a arrow icon that is not highlighed, click on that and now you have the option to make items selectable or not by clicking on the arrow next to the object

I just looked at 20 answers to this question online and found my answer here: it has to do with enabling and disabling selection in the Outliner.
In the Outliner, I had accidentally put my object in an unselectable collection. I'm using reference images, and I had made a collection to put them in and then marked the collection as unselectable so I wouldn't always be selecting the images by mistake. Then I added my mesh but forgot that it was inside that unselectable collection.


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How to set origin points of multiple objects to a corner of their bounding boxes with Python?
So, I’m new to scripting in Blender but I do have a project which requires me to change the origins of all the meshes to minimum X, maximum Y and minimum Z coordinates of their bounding boxes so the left-down corner. A project consists of several meshes and it’s really repetitive. If it’s possible I would love to know how.

Hi. I hope you don't mind my edit. Do you need the bounding boxes of the objects to be in global space or in local spaces of the objects?

First member of bounding box coordinates
The local coordinates of the 8 corners of the bounding box can be found via
bbox = [Vector(b) for b in o.bound_box]

ordered such that the bottom left hand corner is the zeroth element.
Python console code on default cube
>>> bbox = [Vector(b) for b in C.object.bound_box]
>>> for i, v in enumerate(bbox):
...     i, v
...
(0, Vector((-1.0, -1.0, -1.0)))
(1, Vector((-1.0, -1.0, 1.0)))
(2, Vector((-1.0, 1.0, 1.0)))
(3, Vector((-1.0, 1.0, -1.0)))
(4, Vector((1.0, -1.0, -1.0)))
(5, Vector((1.0, -1.0, 1.0)))
(6, Vector((1.0, 1.0, 1.0)))
(7, Vector((1.0, 1.0, -1.0)))

Test script run on selected objects in edit mode (v2.8)  Subtract the LHC from all local coordinates. Globally move the object to reflect the change in origin.  Note on re-reading your question, might want to use index 3
Edit.  Made this a lot more robust. Since any or all of the selected mesh objects may share the same mesh, only want to set the origin of the mesh once, and globally shift each object using the adjusted mesh. For this a collections.defaultdict is used with the mesh as a key, and a list of objects using that mesh the values.
import bpy
from mathutils import Vector, Matrix
from collections import defaultdict
context = bpy.context

meshobs = defaultdict(list)
for o in context.selected_objects:
    if o.type == 'MESH':
        meshobs[o.data].append(o)

for me, obs in meshobs.items():
    o = obs[0]
    bbox = [Vector(b) for b in o.bound_box]
    lhc = bbox[0]
    T = Matrix.Translation(-lhc)
    me.transform(T)
    for o in obs:
        o.matrix_world.translation = o.matrix_world @ lhc

Related
Setting mesh's origin in python (2.8)
Set origin to bottom center of multiple objects

When I was about 10, I was in a geography lesson. The teacher had drawn a circle on the board, with an arrow through it.  "This is the Earth,", he said, "and this is North, which is at the top." I stuck my hand up eagerly : "Not necessarily, sir!".. for which I was unceremoniously removed from the classroom and made to stand in a corner of the hall outside.... I mustn't do that again...

Was it chalk on a blackboard?  Please feel free to elaborate if you think answer is "not necessarily so".  Did have 2 where i meant 3 re minx, maxy, minz., which will ensure all vert coords are x and z >= 0 and y <= 0.


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Modelling and rendering an "impossible object"
I'm trying to make an object in blender that look like this:

I want to make the final render turn out 3D. Is this possible to do in Blender?
Is there some trick to making these objects?
This would be similar to what I would want.

You can't
The 3D shape of a impossible object (this one is called a Penrose square) isn't defined, so you will have a hard time recreating the mesh representation (i.e. exact vertex location and connectivity) of something that can't be described in the 3D space.
... but there are tricks
However, you can do the same thing that people do when photographing such objects: creating an object that looks like the Penrose drawing, but only from an angle. // Edit >> Note: this is more easily done with an ortographic camera, as MrTheRich's answer suggests! If you need/want to go perspective (for example, to composite it on a photo background), a higher focal length is advisable.
For example navigate this or this model on sketchfab: you will see that some of the edges that "look" connected, are actually separated.
There are also ways to use curved shapes that only look straight when seen from the camera. This allows to retain the connectivity.
Shadeless?
You may notice that people who have tried that have often used shadeless scenes.
This is because the shadows introduce an extra complication, since the light "sees" the scene from a point of view that isn't tricked (the trick only works in the direction of the camera), so it tends to give the trick away! You can use a very soft light, close to the camera. It will probably look alright.
One possible shading, that requires using the "invisible curve" trick, which keeps the edges' proximity, is Ambient Occlusion: it only needs to be realistic around the edges.

Edit Nov 6 2020 – There is a wonderful example and write-up on the process in today's blog post on sketchfab

I actually have a Penrose triangle that I modeled in Blender many years ago in my avatar and I can confirm that this answer is spot on. The fact that there's a shadow is one thing I am quite proud of. If you zoom way in (upwards of 200%), you can see the seam at the right side of the top corner, though the texture helps hide it pretty well (another aspect I'm happy with).

I love that I now have a way to look at impossible objects and think of them as being these real "alternatives".

In addition to precise lighting control, you'll also likely want to use an orthographic projection. (It still can be done with perspective, it's just harder.)

I have worked a lot with making impossible objects and 3D print them. The "trick" in your picture, is that it is something in 2D, but our brains try to interpret it as 3D. So to make this object in 3D, you would have to go the other way: "project" it back to 3D. This will only make it look this way from certain angles/distances, though.
Here are some examples I have made. They are based on ambiguous cylinders math by Kokichi Sugihara. Check out his papers for how to do this.

File on thingiverse - or try rotating it here
As you can see, it's really a curved shape, but from certain angles it looks like a star/flower, or from another angle it's a circle.

This is excellent. I kinda want the arrow.

Wow I'm impressed.

But these are not impossible (Proof: you made them)

The trick to this is to use Orthographic mode in the camera instead of the default perspective mode. This makes objects in the distance appear as big as objects in the front which helps with building whatever illusion you make.
If you study the many impossible illusion effects available, you see that they are all orthographic and don't have perspective.
Further more, there are other tricks with lighting explained in the other answer. But orthographic vs perspective is one of the most important tricks.

This works if the end result should have an orthographic view. But if you intend to construct an impossible object to be used in non-orthographic renderings, you should use non-orthographic views. To be more precise, use the exact same camera/view which you intend to use in the final rendering.

Now suppose one were to transform the object as the viewer moves about or rotates it so it stays impossible... >:)...

People have already given brilliant answers, this is just a reminder that in some situations it's easier to cheat. Depending on your project you may be able to get away with using a 2d sprite on a plane and animate distortion effects on the plane in time with any camera movement to give the illusion of a 3d impossible object.
Not expecting this to be the optimal solution, but just a reminder that you only have to have your renders look real from the angles they're going to be seen from.

You CAN make this image but you have to make an optical illusion like an optical illusion.
It will matter from prospective. The shape doesnt even need to be complete to be honest.
So think outside the box and hide your fake shape sides.
If you want to make it actual, then you cant.


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Visual aid to show IK Rotation Limitations
I'm working with rigging right now and would like to know if there is any visual aid in blender 2.7x to show me the limitations of a bone rotation in a chain?
Such as in this picture of 2.6 documentation:

I can't find any button or shortcut to do so.
Thanks in advance.

Related https://blender.stackexchange.com/questions/27143/removing-dotted-assist-lines-problem-only-occurs-when-appending

Two years and no answer, damn, I've been trying to find the answer to this for a while now and just decided to click on everything i could find and eventually found the answer.
In the properties panel, hot key is N, under the display sub heading, tick "Relationship Lines" and those visual aids should appear yet again.
Hope this helps anyone still looking for the answer.

Damn, I also forgot about this question. Never found a solution until now. Thank you a lot.

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


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Re-do view of a photo via DEM data and Blender
I'm trying to re-render
 -
I hopped to generate some jewelery out of the rendered view.
So I found some DEM-data (DEM=digital elevation model) of the region and added a camera and a plane to mirror the mountains there.
Here's the blend file of the scene I created so far
I just can't seem to recreate the view from the photo, or even something close to it. I first tried with just the plane with a displacement modifier on the UV-data and tried to move the camera in to the region,
but this didn't came to fruition.
After some other things I tried I can kind of recreate the view with the one side of the UV-map (of the plane) being scaled to zero - trying to mirror the view from the camera.
(you also see this in the blender file, this is where the shot was approximately made)
I was wondering if someone did something similar to this and might help me.
The most straight forward thing I came up with was that I massively scaled the plane up and tried to physically move the camera in to the region, but this just didn't work. The blender cycles camera just skewed the view too much, the angles and everything seemed off...
edit: To be clear: my problem doesn't lie wit generating the mesh with displacement modifiers, subsurfing, etc. But more with how to then make the camera see more or less the same as in the photo

Make sure the aspect ratio and lense simulation is the same as was present in your camera.

Do you mean something like using the photo as an semi-transparent reference in your camera view?

If you mean view from camera looking somehow like this, then you can accomplish that by using Lens Distortion node (of course, camera itself is tilted slightly)

If you're trying to do (render a scene that perfectly mimics the real-life photo) what I think you're trying to do, then there's a lot more involved than what we'd reasonably be able to write here. But there are a few steps that can get you closer.

A good place to start is Blender's 2D Camera Tracking documentation. You'll want to look at the metadata for the photograph, or otherwise learn a bit about your camera. There are a lot of parameters that go into making a photo look the way it does.
It looks like your camera used an 'HDR' setting to get the image's colors and contrast to look so stellar. You may have some difficulty making this happen in blender, but it can be done.
As for the orientation and location of your camera, you're right to start by blowing the mesh up considerably (it will help make the light and shadows more realistic). Moreover, the world is really really big. It may take a lot of scaling before your geometry even starts to approach the correct scale. Whenever I'm having difficulty with scale (it's easy to get 'lost' in Blender-units) I add a roughly human-shaped object (normally just a tapered cylinder with an icosphere head) and put it in my scene. Then I scale objects until I could see them being the right height. (It's hard here because mountains are big... But it'll help you when you're orienting the camera. It'll probably go a lot closer to the mesh — that is, 'lower' to earth — than you're imagining.)
Before you even begin with textures and colors, though, you need to
get the geometry right. I'd suggest making this image your camera's
background reference
image
and using this to establish how to position your camera to get the
right image.
Note that your heightmap may not be scaled properly in the z-direction: Once you get the camera in the right position, I often find that my mountains look a bit mole-hilly. sz to scale in the z-direction only; with a camera at 'eye level' this may give you a better-looking middle-distance.
Use clues in the photo to orient your camera. Clearly the camera is pointed at a certain set of mountains from a certain direction, so start by putting your camera in the right geographical location. Point it in the right direction. Now look at your horizon in the photograph — it's definitely angled! Orient your camera so that the xy plane is at the same angle, and your image will start to come together.

My parting suggestion is to play around with the focal length: I find a much lower angle will make the environment appear larger (with the requirement that you move the camera 'back' to maintain the contents of the frame). Play around with that slider and see the results; I think that may be why you're not getting the right 'feel', even though the geometry is all there.

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


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Video Sequencer: What are the advantages of Effect Strips?
Let's say that I want to change the color balance of a strip, I can either:

Select the strip, open the N panel, click on the Modifiers tab and create a Color Balance modifier
Or select the strip, ShiftA > Add Effect Strip > Transform, keep the effect strip selected and give it a Color Balance modifier, which will affect the original strip

What are the advantages of the second solution? I've cited Color Balance but I could ask about the transforms as well.
Thanks in advance

me personally i can only "effect strip" -> "add" if i select two strips minimum. Are u using the old Blender versions again!?

You can give an effect strip to a single strip, even in 3.1: select a strip, Shift A > Add Effect Strip > Transform, and you can transform the effect strip or give it a modifier, not sure what are the advantages (maybe for the transform operations, you can easily mute)

You don't need to add a Transform Effect Strip to color balance a strip, you can just add a Adjustment Layer for that. It works just as Adjustment layers in other programs.
Setting its blend mode to Cross will then allow you to adjust its "influence" with the opacity value.
So the advantage of using it instead of applying the effect directly to the strip as a modifier is the ability to change this "influence" with the opacity value and the ability to toggle all the effects on and off more easily by just hiding/unhiding the layer.
Another advantage of the Adjustment layer is that you can apply it to more than one strip as it influences all the strips that are underneath it instead of being just limited to one strip like Effects Strips :

It is also good to know that you can apply Effect Strips to an Adjustment Layer which would allow you to apply an effect strip(s) to multiple strips without having to group them into a metastrip.
In conclusion, as an answer to your question, I would suggest you to apply directly the color balance as a modifier if it's just a basic one that you want to apply to single strip but use an Adjustment layer if you want to have more control over it and/or use it on multiple strips.
You should use the Transform strip only if you need to perform transformations (rotate, scale, translate) to your strip.
As a side note, I would like to point out that you can transform a strip without using the Transform Effect Strip, there is a Transform section under the strip tab :

which allows you to do pretty much the same thing as a transform strip would hence making the transform strip almost pointless.

Ok thanks a lot, so from what I understand, Effect Strip > Transform is rather useless. Maybe something that is missing is a way to control the opacity of an effect strip only.

Frankly, since the Transform strip crops the image to what's visible, I don't really see a reason to use it instead of the default transform. It can be handy if you want to stack transformations tho and the VSE transform tools addon uses it to stabilize a footage but this crop thing is really annoying.

One thing I always do if I use an effect strip is, hide the original strip and set the effect strip to alpha over, this way I can control the opacity of the effect strip.


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How to Rig Multiple Rotational Axis' for One Object?

Fairly new to Blender. It seems there's a foundational concept I'm missing to enable me to create an object which has multiple rotational origins at the same time. Each child can only have one parent, so the method to achieve this must make use of other Blender features.
Think about how a skateboard on the ground can rotate the entire deck around each set of wheels. The deck would be the object and each set of wheels would be a rotational axis.
I don't necessarily need a full descript answer, even a link to a previous answer or tutorial that will point me in the right direction would be appreciated. Thanks!

I've made a bit of advancement learning of the pivot point drop down box. With that I should be able to parent all objects to an empty, then use 'active pivot point' to rotate around different axis'.
This may enable me to animate a short segment, but it doesn't feel like proper rigging. If anyone has direction to learn how to do this with rigging or modifiers that would still be appreciated.

no, the Transform Pivot Point can't be used for animation, it can only be used to rotate object when you work on your 3D scene, when you animate it will take the origin of your object into account, you could use parents to change the object rotation center but I guess it depends on the situation, maybe show a precise animation you're trying to achieve

The active pivot point changing has been working in some animation test so far, does it not work when rendering?
I may be missing an approach, but I found parenting/children to be a dead end because I want each wheel to be able to move the deck and the other wheel around it's center...can't figure how to do this when only a single parent is permitted. The deck also needs to be free to tilt laterally independently of the wheels, like an actual skateboard.
I'm interesting in learning the method to make it a functional rig though.

As you say there's a problem for objects or bones to be both children and parents, I think there was a similar question sometimes ago that found an answer but I can't put my hand on it, I hope someone will answer. The first 2 images you show are easy to reproduce but if you begin to add several rotations it begins to be tricky and if you can't find a way I wonder if the best is not to just create keyframes of position A to B to C etc...

Somewhat related https://blender.stackexchange.com/questions/184016/animation-using-a-different-axis-to-rotate-the-entire-object-than-the-normal-o

This is the basis of the problem of foot roll in building bipedal rigs.  There are two approaches commonly used.  I'll describe a stripped down version of the simpler of the two.

The above three bone rig is called the rocking rig.  The head and tail of the rock bone are the two pivot points.  The parent bone serves to avoid the problem of parenting.  The control bone is the rocking bone.
This rig works by rotating the control bone on its local Z axis, currently oriented along the world Y axis.  It is usual to lock the rotation of this bone.  As the bone rotates counterclockwise from its center position, the rock bone will rotate counterclockwise on its head.  As the control bone rotates clockwise from its center position, the rock bone will rotate clockwise on its tail, as a result of being parented to the parent bone.
The positioning of the bones is critical.  They must lie in a line on the same axis, in this case the X axis. The head of the parent bone must lie in the same position of tail of the rock bone.  This is one of the two pivot points.  The other pivot point lies at the head of the rock bone.
It is convenient for the control bone to be parallel to the parent bone and for your purpose for the parent bone to be perpendicular to the rock bone.
None of the bones are connected to the others.
The orientation of the axis of the bones matters.  They should all have their Z axis parallel to the world Y axis and pointing in the negative direction.
The parent bone is the parent of the rock bone. This is so that rocking the rock bone on its tail will work.  The parent and control bones are unparented, although in a rig they would normally both be parented to a root bone.
Each of the rock and parent bones have a copy rotation constraint to copy rotation from the control bone.  Each also has a limit rotation constraint.  The limit rotation constraints are what divide the rotating between the two pivot points.   The constraints all operate in local space.
Here are the constraints
For the rock bone:

For the parent bone:

You could try to parent the object to a different parent each time it needs to change its pivot point, there's an addon that makes it easy, it's the Dynamic Parent by Roman Volodin. Demo here for example.


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How to rotate according to face normal?
I want to place cursor with copying face rotation (Normal?)

First I place cursor to where door handle will be placed

Then create a circle object where cursor is placed.

I want to rotate my circle according to face rotation(Normal?). Is that possible?

select the face and in the Transform Orientations panel, you can create a custom orientation (click on the "+" button)

@moonboots I can`t find where is '+' button

Select the face and in the Transform Orientations panel, click on the "+" button in order to create a custom orientation:


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Desaturated Animation After Rendering
Working on this animation and the colors look correct in the 3d viewport:

but when I render the PNGs:

and then render to AVI RAW:

in the VSE it becomes super desaturated.  I have the "Display Device" at sRGB, "View Transform" is standard, "Look" is none, and "Sequencer" is sRGB.
Does anyone have an idea what is going on?
Blend file here (2.80).
Thanks!

Any progress on this? It would be good to know for certain how the output is being busted up.

You are on a Mac right?
I’m guessing it is post 2015 MacBook Pro?
Blender doesn’t support the proper display devices for MacBook Pros. You’ll need my GitHub version.
TL;DR: What you are seeing in Blender is wrong, and Preview is interpreting it as correct. I’d also encourage you to not render with the sRGB OETF as it is subject to colour skew with saturated colours.
PS: If this confuses you, I’ve recently covered this very subject over at the Hitchhiker’s Guide to Digital Colour. I’d recommend starting at the first question if this guess of an answer proved correct. https://hg2dc.com/. Feel free to ask any questions.

This is what I configured that made my image sequence render perfectly fine without weirdly desaturating or altering the contrast.
Display Device: sRGB
View Transform: sRGB OETF
Look: None
Squencer: sRGB OETF


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How would one code a pie menu with an additional traditional menu beneath it?
What would be the nicest way to code(in Python) a pie menu in Blender 2.79 or 2.8, that would have another menu as an addition to the standard 8 pie menu choices?

After playing with it for some time I found that this kind of works:
import bpy
from bpy.types import Menu
class VIEW3D_PIE_template(Menu):
    bl_label = "Some Pie Menu"

    def draw(self, context):
        layout = self.layout
        pie = layout.menu_pie()
        pie.operator("mesh.primitive_cube_add")
        pie.operator("mesh.primitive_cube_add")
        pie.operator("mesh.primitive_cube_add")
        pie.operator("mesh.primitive_cube_add")
        pie.operator("mesh.primitive_cube_add")
        pie.operator("mesh.primitive_cube_add")
        pie.operator("mesh.primitive_cube_add")
        pie.operator("mesh.primitive_cube_add")
        pie.separator()
        pie.separator()
        gap = pie.column()
        gap.separator()
        gap.separator()
        gap.separator()
        gap.separator()
        gap.separator()
        gap.separator()
        gap.separator()
        menu = gap.box()
        menu.scale_x = 2.5
        menu.operator("mesh.primitive_monkey_add")
        menu.operator("mesh.primitive_monkey_add")

def register():
    bpy.utils.register_class(VIEW3D_PIE_template)

def unregister():
    bpy.utils.unregister_class(VIEW3D_PIE_template)

if __name__ == "__main__":
    register()

    bpy.ops.wm.call_menu_pie(name="VIEW3D_PIE_template")

I wonder if there is a nicer way. This feels 'hacky' and it would be nice to have a menu that would have expandable sub-menus if that is possible at all. I realize that might be too much to wish for... Any advice?

You can just append another menu as a submenu: How to make a sub-menu with Python?, with some formatting it could look like this: https://pastebin.com/7d8dzpwi. You can also do fully custom stuff with bgl drawing inside modal operator, but you would have to re-implement the pie menu functionality.

Thank you! That really helps. That's all the functionality I wanted. I am still hesitating a bit about the code now - I mean all the separators to go around the pie menu... But it works, so I really appreciate the help.

You can just leave 2 separators there and scale the gap column with gap.scale_y = 5.0 to create the distance, but this could mess with spacing of anything put after the gap.box() item in the column. So multiple separators are imho the best to make the space, I would not worry about it. You can add some comments in the code to make it feel less hacky, like # spacing between pie and column menu followed by the separators.

.... putting the separators in a for loop  or a draw_gap(self, layout, count=7):  method will "clean" the code up somewhat.

I am just scaling a column with one separator with .scale_y now for the gap. That seems nicer. Other than that I need two separators to start drawing my additional 'menu' at the correct place of the pie menu. I think that will have to be nice enough.

The solution I ended up with is the same as discussed in the comments:
import bpy
from bpy.types import Menu

class Submenu(Menu):
    bl_label = 'Some Submenu'
    def draw(self, context):
        layout = self.layout
        layout.label(text="Some Submenu")
        layout.separator()
        layout.operator("mesh.primitive_cube_add", text = "Some Submenu Operator", icon = "BLENDER")
        layout.operator("mesh.primitive_cube_add", text = "Some Submenu Operator", icon = "BLENDER")
        layout.operator("mesh.primitive_cube_add", text = "Some Submenu Operator", icon = "BLENDER")
        layout.operator("mesh.primitive_cube_add", text = "Some Submenu Operator", icon = "BLENDER")

class Pie_menu(Menu):
    bl_label = "Some Pie Menu"
    def draw(self, context):
        layout = self.layout
        pie = layout.menu_pie()
        pie.operator("wm.call_menu_pie", text = "Some Other Pie", icon = "RIGHTARROW_THIN").name="Pie_menu"
        pie.operator("mesh.primitive_cube_add", text = "Some Operator", icon = "BLENDER")
        pie.operator("mesh.primitive_cube_add", text = "Some Operator", icon = "BLENDER")
        pie.operator("mesh.primitive_cube_add", text = "Some Operator", icon = "BLENDER")
        pie.operator("mesh.primitive_cube_add", text = "Some Operator", icon = "BLENDER")
        pie.operator("mesh.primitive_cube_add", text = "Some Operator", icon = "BLENDER")
        pie.operator("mesh.primitive_cube_add", text = "Some Operator", icon = "BLENDER")
        pie.operator("mesh.primitive_cube_add", text = "Some Operator", icon = "BLENDER")
        pie.separator()
        pie.separator()
        other = pie.column()
        gap = other.column()
        gap.separator()
        gap.scale_y = 7
        other_menu = other.box().column()
        other_menu.scale_y=1.3
        other_menu.operator("mesh.primitive_cube_add", text = "Some Menu Operator",icon = "BLENDER")
        other_menu.operator("mesh.primitive_cube_add", text = "Some Menu Operator",icon = "BLENDER")
        other_menu.menu('Submenu', icon='RIGHTARROW_THIN',  text='Some Submenu...')

def register():
    bpy.utils.register_class(Submenu)
    bpy.utils.register_class(Pie_menu)

def unregister():
    bpy.utils.unregister_class(Submenu)
    bpy.utils.unregister_class(Pie_menu)

if __name__ == "__main__":
    register()

    bpy.ops.wm.call_menu_pie(name="Pie_menu")

It works exactly as I wanted:

hello, is it normal to have Warning: Pie menus with more than 8 items are currently unsupportedthis error message printing every time i call the pie ?

It is not an error message, it is a warning message - it says so: 'Warning:...' That might be new. I don't think I saw it at the time of writing this. Submenu is not working in 2.80 anymore as well, something must have changed during the development. I'll try to look into it if I have a spare minute.

Warning: Pie menus with more than 8 items are currently unsupported
Pies larger than 8 are no longer supported by the blender formula.

Please create a pie with no more than 8 items, including submenu items.
Also, please refer to the submenu specifications in
In the case of 2.8
#    layout.label("Some Submenu")
     layout.label(text="Some Submenu")

will work.
import bpy
from bpy.types import Menu

class PIE_MT_Submenu(Menu):
    bl_label = 'Some Submenu'
    def draw(self, context):
        layout = self.layout
        layout.label(text="Some Submenu")
        layout.operator("mesh.primitive_cube_add", text = "Some Submenu Operator", icon = "BLENDER")
        layout.operator("mesh.primitive_cube_add", text = "Some Submenu Operator", icon = "BLENDER")
        layout.operator("mesh.primitive_cube_add", text = "Some Submenu Operator", icon = "BLENDER")
        layout.operator("mesh.primitive_cube_add", text = "Some Submenu Operator", icon = "BLENDER")

class PIE_MT_Pie_menu(Menu):
    bl_label = "Some Pie Menu"
    def draw(self, context):
        layout = self.layout
        pie = layout.menu_pie()
#        Left
        pie.operator("wm.call_menu_pie", text = "Some Other Pie0", icon = "RIGHTARROW_THIN").name="Pie_menu"
#        Right
        pie.operator("mesh.primitive_cube_add", text = "Some Operator1", icon = "BLENDER")
#        Bottom
        other = pie.column()
        other_menu = other.box().column()
        other_menu.operator("mesh.primitive_cube_add", text = "Some Menu Operator7",icon = "BLENDER")
        other_menu.operator("mesh.primitive_cube_add", text = "Some Menu Operator7",icon = "BLENDER")
        other_menu.operator("mesh.primitive_cube_add", text = "Some Menu Operator7",icon = "BLENDER")
        other_menu.menu('PIE_MT_Submenu', icon='RIGHTARROW_THIN',  text='Some Submenu...')
#        Top
        pie.operator("mesh.primitive_cube_add", text = "Some Operator2", icon = "BLENDER")
#        Top_left
        pie.operator("mesh.primitive_cube_add", text = "Some Operator3", icon = "BLENDER")
#        Top_right
        pie.operator("mesh.primitive_cube_add", text = "Some Operator4", icon = "BLENDER")
#        Bottom_left
        pie.operator("mesh.primitive_cube_add", text = "Some Operator5", icon = "BLENDER")
#        Bottom_right
        pie.operator("mesh.primitive_cube_add", text = "Some Operator6", icon = "BLENDER")

def register():
    bpy.utils.register_class(PIE_MT_Submenu)
    bpy.utils.register_class(PIE_MT_Pie_menu)

def unregister():
    bpy.utils.unregister_class(PIE_MT_Submenu)
    bpy.utils.unregister_class(PIE_MT_Pie_menu)

if __name__ == "__main__":
    register()

    bpy.ops.wm.call_menu_pie(name="PIE_MT_Pie_menu")


text:
Audio/Video out of sync in rendered video, but not in VSE
First let me apologize to ask this question, as this has been basically already asked, for instance here, here and here. However these answers don't seem to provide an understanding what's really going on, so I will pose my question anyway.
Every once in a while the video in a rendered video file will playback much faster than the audio, despite audio and video being perfectly in sync in the VSE. This problem seems always to pop up when then input source video is "mostly static", i.e. when the change from one frame to the next is miniscule (e.g. a screen recording). I should also add that I record the videos in question using a lossless codec (FRAPS or lagarith).
From the other questions linked above, I get the impression that this is due to Blender (or rather its version libavcodec) incorrectly decoding the compressed source video. It is also mentioned in one answer to the above questions that this is related to the use of b-frames in the encoding algorithm. However I had this problem also using the lagarith codec, which apparently uses only keyframes/i-frames.
Now in order to turn this cry for help into a question, let me ask: What the hell is going on here?
More precisely:

Why can Blender (or its version of libavcodec) apparently correctly decode and show the video in the VSE, but not render it correctly? Is the decoding in the VSE done differently than in rendering?
What version of libavcodec is used in Blender 2.74? Is the implementation of e.g. lagarith faulty in this version? If not, then why does Blender mess up the rendering?
It has been suggested that one should use "Blender-friendly" codecs for compression. Which lossless codecs are known to be so?

Edit: It seems there are several error sources here, which just makes everything much more confusing. The problem of the video playing back at twice the normal speed I had with this one particular lagarith encoded source seemed to stem from a corrupted (??) .blend file. Namely during editing Blender got stuck and I had to force it quit. When I re-opened this file Blender didn't give me any complains, but comparing its file size with the sizes of some other .blend files which were similar, I noticed that it seemed about 3 kB smaller than the rest. Opening this file and saving it to a new file ("Save as") got rid of this playback issue. However the video is still out of sync, even more subtly. Instead of the video globally playing back faster, it sometimes seems to "get stuck" and then "catching up again".
These issues are also already visible in the VSE, so it seems that my problem at least in this instance is solved. On the other hand this makes the behaviour of Blender seem even more mysterious, as I do not understand how a corrupted (was it even corrupted??) .blend file can lead to such an effect.
As I wrote, I experienced this issue with several videos, one of them being a video encoded in FRAPS. There the audio and video seemed in sync in the VSE, but wasn't in the rendered video. Strangely, after re-creating this .blend file from scratch, the audio and video now was out of sync even in the VSE. I tried transcoding it with ffmpeg, and this also gave an out of sync video. However transcoding it with Windows Movie Maker gave perfect result. So I suppose that for this particular video, the problem is that the fraps codec is implemented imperfectly in ffmpeg/libavcodec.
2nd Edit: The problem is back. Apparently it didn't have anything to do with the file being 'corrupted'. Running blender again on the very same file this time produced again an out-of-sync video. This issue seems to appear and disappear randomly.
3rd Edit: Still no clue why it only appears sometimes. But I noticed something else. The audio in the rendered video is as it should be, i.e. its start and end are as defined in the .blend file. However the last frame in the rendered video is actually way beyond the end frame. For some reason Blender consumes more video frames than it is supposed to be. I am going to file a bug report on this.

If you identify the codec, what frame rate is returned using a recent FFMPEG?

Problem reoccured to day (despite using proxy/timecode). Running ffprobe on this file gave me the following output for video stream: "Stream #0:0: Video: fraps (FPS1 / 0x31535046), bgr24, 640x480, 21429 kb/s, 30 fps, 30 tbr, 30 tbn, 30 tbc)". Thus the reported frame rate coincides with the frame rate I set in fraps (of 30 fps).

I was asked to take a look at this post. Codecs can be rather puzzling to diagnose from a distance, but it does seem that some information can be offered.

This problem seems always to pop up when then input source video is
  "mostly static", i.e. when the change from one frame to the next is
  miniscule (e.g. a screen recording). I should also add that I record
  the videos in question using a lossless codec (FRAPS or lagarith).

The “mostly static” comment here is interesting. This does indeed sound like an I versus P / B frame issue, as the “mostly static” frames would be subject to many more instances of P / B frames. While I am unfamiliar with Lagarith or FRAPS, I would be extremely surprised if a non-GOP codec had this issue, as your solution hints toward.

Why can Blender (or its version of libavcodec) apparently correctly
  decode and show the video in the VSE, but not render it correctly? Is
  the decoding in the VSE done differently than in rendering?

The VSE is using certain techniques to display the video that, when decoded on a shot by shot basis for rendering are different. This is why non-GOP codecs are more robust, or time code indices will yield more consistent results. This is also why most always-online NLEs will transcode upon ingestion; to avoid the codec problems as well as try to reduce the always-online image degradation issues.

What version of libavcodec is used in Blender 2.74? Is the
  implementation of e.g. lagarith faulty in this version? If not, then
  why does Blender mess up the rendering?

FFMPEG's version was a bit nasty on some platforms as it previously used a bundled version on some while on others it used a local version. If you check the ffcompat code, you can see many version checks to support generic versions of FFMPEG.

It has been suggested that one should use "Blender-friendly" codecs
  for compression. Which lossless codecs are known to be so?

The easiest way to avoid all of the codec mess is to rely on still frame intermediates. If you must for whatever reason rely on codecs, you are likely going to be constantly faced with these sorts of issues unless you manage to coax one of the codecs to behave under generated timecode indices. I would also speculate that FFv1 should be a reasonable choice to test and put under duress, given the nature of its design. If you try FFv1, it would be interesting if you reported your results back here for future reference.
Best of luck.

Thank you so much for this quite informative answer! Didn't expect anymore to see some light shed on this issue. I will try your suggestion and transcode on of the 'troublesome' videos to FFv1 to see whether this helps. Even though adopting to generate timecode seems to have banished this issue, it also make video editing a bit more awkward since generating proxy/timecode takes quite a long time. Perhaps transcoding to an intermediate codec would be a better option.

Don't take my word as the word, though. Remain skeptical. The most telling part of your question was the "mostly static" comment, which really hints at encoding formats, and timecode solutions. I haven't looked at the FFMPEG situation across platforms in quite some time. To be honest though, if you are serious about imaging, I'd encourage you to adopt an offline pipeline and rely on a stills based intermediate format for online work. If you must, rely on a frame accurate codec that holds up (again, let us know about FFv1) during offline work. I'm glad this answer helped you out in some way.

Okay I've tried the FFv1 codec now, and it doesn't help unfortunately. Video sync is completely messed up in VSE and in rendered video.

@BlenderBender Interesting. Does that include using the timecode generated indexes? Did you generate the FFv1 using FFMPEG standalone? Does it seek well? If it seeks fine, then the audio is likely an encoding botch. As an aside, are you using WAV for the internal audio codec? Similar issues exist for audio of course...

The problem re-occured today. I generated timecode for the FPS1-encoded video (with "Record Run"). It was totally in sync in the VSE, and it seeked well. But when I rendered it, I had the same issue as before.

P.S.: Used WAV (PCM_s16le) for audio.

Unfortunately I can't really answer my questions 1, 2, 3, but at least I figured out how to get rid of said problem. It seems that Blender cannot be trusted to render a video correctly, if said video is not endowed with a timecode, even though most of the times Blender seems to do well without one.
TL;DR: Generate a "timecode" for each video strip before rendering, by selecting the strip, checking the "Proxy/Timecode" checkbox in the "Edit Strip" menu, choosing a timecode option e.g. "Record Run" and finally running "Rebuild Proxy and Timecode Indices".
Update 2017-04-17: Unfortunately, my solution isn't universal. I just had this problem re-appear today, despite generating timecode as proposed above. Not only that, but in fact the a/v-sync issue disappeared when I disabled the use of timecodes! There seems to be something seriously wrong with Blender.
Update 2017-04-21 This was with Blender 2.76 (the last XP-supporting version). I tried reproducing this issue today with Blender 2.78c, but there it was fine. So perhaps, this issue only affects older versions of Blender.
Update 2017-05-24 The problem reoccured today: I can confirm that this issue still exists in Blender 2.78c.

+1 for fixing my problem with video without audio. Read a number of answers and this was the only one which worked.

It isn't Blender, it is codecs. Hence why the above solution I provided ultimately ends with "use still image frames", which is the only surefire solution.

I don't see how it's codecs. It is not even a function of codecs: this happens to me even if I transcode the source video to ffv1. Also, other players are perfectly well capable of seeking these videos properly. And in the instance of this problem that occurred to me yesterday, Blender actually did properly render the video (and thus seeked the video properly), but only when I disabled the timecode Blender generated. How could this be?

In the end, the issue is the nature of the internal timestamps with certain codecs. Sure, there may be a bug or some player that manages fine, but the end sum is that it will depend on architecture, and there is no single solution that will solve all cases when dealing with a multitude of codecs. This is also precisely why there is an "ingest" phase in the bulk of NLEs. There are just too many variables to offer a solution here, and why Blender should gut the codec support down to two or three. Just far too complex.

As far as I can tell, this is not an issue of "it doesn't work with all codecs" but rather "it works most of the time, and when it does not, it fails for all codecs".

**edit: The problem went away on its own for some reason. I converted alot of my project to 16 bit png as I added more edits. So also believe this is the solution for fixing the problem, that the video originally used (an h.264 mkv) was to blame. And others have replied stating the same here and elsewhere. Animation cache doesn't seem to to fix audio issues like it used to, potentially improves quality slightly though. Honestly the quality is bad to begin with using audio/video renders....just use mixdown and recombine with ffmpeg or some other program that won't re-encode (tossing it back in blender re-encodes remember so dont do that).
I don't see any solution here, so here is mine :) I had the same problem. My fix for 2.79b was
1. update the animation cache right before u render under scene->audio
;2. render my video without an audio codec, specifically try it as matroska h.264
;3. mixdown ur audio as a .wav
;4. combine the audio and video in ffmpeg. Use command:
ffmpeg -i videoname.mkv -i audioname.wav -c copy makeupanoutputname.mkv;
you guys can go through on ur own and determine what step specifically solves the problem and if other codecs/containers work as well all the same. its probably just NOT rendering with an audio codec that solves the problem.
This is clearly a blender problem and not an ffmpeg problem. I'm very upset that the chosen solution doesn't give people a way to fix anything and is telling us something that the evidence points to being a lie.
VSE: rendered audio is offset (audio+video render)

If you're upset by this problem (as I am), I highly recommend that you open a ticket on their bug tracker. I already opened two of them, but they got ignored; apparently, they don't think this issue is a priority. But perhaps, given that enough people complain, they will change their mind.

Regarding your comment about (lack of) solutions: The only completely reliable way to avoid this issue that I've found is to convert your video into a sequence of images, and import those as an image strip. Yes, this does make video editing way more awkward, but, it is doable.

I've had very similar experiences when opening tickets and asking devs questions. Often ignored or told it's a nonissue. If they can't replicate your system specs exactly, they won't/can't help...that's my experience and understanding so far anyways. This is doubled down by the fact that vse related problems are intentionally sidelined. Although it might help change opinions, I Personally can't recommend this route to myself or anyone else until VSE development is officially resumed.

So after a lot of online searching, I did find an answer to fix this problem, but not in Blender. If you are like me and would like to use Blender for video editing and still get around the issue, then I found a workaround, but you need Shotcut for this. Shotcut is another great free and open-source video editor

Export the entire long video from Blender (the rendered video has desync issues as expected).
Open the video in Shotcut and detach the audio from it.
Use the audio properties to make very fine adjustments to the audio playback speed to suit your requirements (make fine adjustments until video and audio are in sync).

Follow the GIF attached.
(I am using a shorter video in the GIF but you get the idea)

Explanation

Blender has issues while rendering long videos and I noticed that the video is exported at 1.0x speed but the audio is sometimes faster (1.00400x or something like that) and hence the rendered video has audio not in sync with the video.
Another bad thing is that Blender does not really allow very fine playback speed adjustment just to the audio.
One trick is to adjust the pitch of the audio in Blender which in turn changes the playback speed but this is only allowed up to 2 decimal places (not what we want for long videos) and it makes the audio sound funny (since it actually changes the pitch).
Shotcut is a great tool that allows fine playback adjustment, and it also has a pitch compensation feature so that your pitch is kind of unaffected (since we don't want the characters to be sounding funny in our edited video).
Shotcut allows playback speed adjustment up to 6 decimal places.

I had posted a similar question earlier, link to that post can be found here.
I have also created a short video about this, which can be found here.

Unfortunately, it degrades the quality of the audio. Is there a way to add the original audio to the video in Shotcut?

Well, I once posted a question identical to this, which, funny enough wasn't in your list of duplicates. :D
I found after the whole that they actually weren't out of sync, but rather the software I used (Windows Media Player) was being laggy and played it back funny, while other players (VLC media player & YouTube) would do it fine! This is a possibility of you see this occuring after your video is rendered.
If this happens to you before rendering and only in Blender's live playback, most likely you are dropping frames. To fix this, in the toolbar if the timeline window there is a tab called "playback". Open it up and click "AV-SYNCING". Only click it if the checkbox next to the label isn't already checked.

As I wrote, the video plays back fine in VSE. Only the rendered video suffers this problem, and this problem shows up in every player.


text:
"Curve From Mesh/Text" not working on wireframe of cube
I was following this link on solidifying edges. When I went to convert the mesh to a curve, nothing happened. Here's what I starting with a new file:

Select cube
Tab to edit mode
Ctrl + F > Wireframe
Tab back to object mode
Alt + C > Curve from Mesh/Text

Nothing happens. I noticed that it works if I add a Grid or Circle and try to convert those. What am I doing wrong?
I have Blender 2.71 (Release Candidate). I also tried converted the cube directly without converting it to a wireframe, but that didn't work either.
Context: I'm trying to create a picture like this, with shadeless faces (that occlude the background) and dark edges:

possible duplicate: http://blender.stackexchange.com/questions/9271/render-a-wireframe-with-equal-thickness-in-cycles

i've addressed the question anyway, but the answer to the thing you want to achieve is to use Freestyle render lines. You will need 2.72 upwards.

Conversion to wireframe does this in essence, for every face on a Mesh.

The wireframe conversion transforms each face into thin faces interior to  the perimeter of the face, this function has parameters that you can change to adjust the width of those faces, but by default it is rather thin.

As a side note: The Curve from Mesh/Text conversion tool operates best on Meshes if you remove the faces first. (X, remove only faces). If the mesh doesn't have any Faces there is no need to convert to wire-frame (or remove doubles later on).

You can set the thickness of the wireframe to 0.000, and then you'll see little dots on the edges, because it still creates faces but they are so thin they will fall below the 'remove doubles' limit:

Removing doubles would look like this:

At this point you can convert to Curve from Mesh/Text. But I doubt that is actually what you want.

If you follow the link in the first comment on your Question you will be able to render results like this:

Conversion to wire-frame isn't the way to go about rendering with face occlusion.

The link you gave me did the trick! However, the original method you mentioned didn't work because when I deleted the faces, it deleted everything. Although it's not as important now, how should I delete the face in a way the keeps the edges/vertices? Do I need to first created edges/vertices?

read carefully what I said about the delete procedure, and look carefully at the options that appear in the delete menu. https://i.sstatic.net/hyDNK.png

You could try this:

Select the cube
Tab to enter Edit Mode
Delete, only faces
Tab to exit Edit Mode
AltC should convert the mesh to curve

I think you can only convert mesh to curve, if the mesh only consists of edges and vertices, because curves basically also has only edges and vertices

I already said this..


text:
Remove extra points in export to SVG
Following this post, I exported a scene to an SVG format using the bundled add-on ("Render: Freestyle SVG Exporter").
However, when I did that I noticed that the resulting SVG has a bunch of unnecessary points, as shown below:

Is there a way to remove those extra points and only have one point at each corner? (Note that I only have the outer path selected.) I have Blender v2.74.

You could use inkscape's simplify operator (Ctrl L IIRC)

You could report this as a bug in the freestyle SVG exporter.

I'm thinking about doing that. I want to make sure that there isn't some setting that I'm missing, or if this is supposed to be the behavior.

Remove the Sampling modifier from the Geometry modifier stack.
This modifier adds extra stroke vertices at a regular interval.  This modifier is added by default because it is necessary in many stylization situations, e.g., when you want variable color, alpha transparency and/or line thickness along stroke, and when you want to add distortion to stroke geometry.  If you don't need the extra points, you can just remove the modifier.

How do I do this? I looked at the Modifiers section in the Properties pane and saw that no modifiers were added.

Go to the Render Layers properties window > Freestyle Line Style > Geometry, and you will find the Sampling modifier that needs to be removed.


text:
need double helix mesh to follow bezier curve
I need to get my double helix mesh to follow the bezier curve in this screen shot. When I add a curve modifier to my double helix, instead of following the curve, it distorts the size and angles of the mesh in an undesirable way.
How can I get it to follow that curve?

And here's the blend file:

very dependent on both curve and mesh orientations. You may have to rotate the mesh, but difficult to say in which orientations without the blend file. But keep in mind that the curve modifier is a deform modifier, so you mesh will be deformed a lot if the curve angles are too bent

IMHO, too much vertices 800k reaches the limits in order to tune the curve modifier.... try to keep it under 500k, at least... if not (for my CPU) nearly impossible to tune

The curve modifier is a bit of a tricky one, as it requires you to spend a bit more attention to the orientation of the source object. To start with, make the local axis of the object which you want to bend visible in the Object tab / Display section:

In your case, the positive Z Axis is pointing up the direction of the Helix, and this is the direction which you want to deform. Next, Handle the origins. The Origin of the Helix should be at the starting point of the deformation. If it is not, you need later on to locally translate it along its local Z axis to match up the curve (in your file it was centered on the object). If you place it like in this screenshot, you can skip the translation step:

The highlighted axis are the one from the helix, the dark ones the axis of the curve you provided.
Then, make sure that the origin of the curve is at the origin of the helix. You can snap them together using the commands in the Shift S menu:

Now add the curve modifier, and set the deformation direction to Z:

As lemon rightfully anticipated, the curve radius is too small to get nice deformation. Ease out the curve a bit more to fix it.
Blend File is here:


text:
Knife tool keeps popping up
I've accidentally clicked something with the mouse and now when ever I left click the knife tool comes up. I've tried pressing esc, however when I left click again it comes up, I've tried load factory settings, however when I start a new page it happens again.

Make sure you haven't the Knife tool selected in the Toolbar.

The select box is selected

If this is happening in the new project also then probably you have by mistake changes some setting , try going to the keymap and see what are the input settings for the knife tool , and also try to see what you left mouse button is supposed to do , what i think that this much should solve the problem

It worked! Thank you!


text:
Following a blender tutorial and rendering is grainy
So I just recently started using blender as my friends started using it to make models for vrchat, so I decided to learn it as well, I was following the donut tutorial by blender guru but as I came to the rendering step I noticed that my render was much more grainy than his even though we had the same render numbers, any ideas? I tried increasing it further but noticed no difference at all. might the numbers have changed through the updates so they are not the same for the same quality or something?
Specs
GTX 2070 Super
16gb RAM
AMD Radeon 3700x
750w power supply

Denoising feature needs to be used, Andrew (blenderguru) explains how to do it in one of the episodes....

Can you post the two renders? Or at least yours so we can have a look? How many samples?

Does this answer your question? Why is my donut so grainy (cycles rendering)?


text:
Why isn't it filling in when I extrude?
I have a mesh plane, but it won't extrude correctly. I started Blender today, so I am completely new. Here are the pictures:enter image description here

you mean you've extruded but there are no rim?

rim? If that is the fill that is supposed to fill the gap between the two planes then yes.

yes, no side... have you used E to extrude? It looks like you've made a simple duplication

Yes I use E to extrude

I can't tell you what's happening but I can confirm that it's not the way it's supposed to work  :/

Dangit. Well, thanks anyway.

If you selected the whole mesh and extruded it, it is the expected result. To get what you want just select the outer edges of the mesh and extrude it upwards then if you wanna close the top just extrude it aing and press s to scale the extrusion inwards and then press alt+m(assuming it is a circle with a triangle fan filling)

Could you upload your blender file so that we can try to figure out what's causing this to happen: https://blend-exchange.giantcowfilms.com/  Thanks.

It doesn't appear like a circle.. is it a subdivided plane?If so I'd recommend to delete all the subdivisions and then extrude it . Afterwards you can add loopcuts.

Thank you Nxdhin2005 it worked! But it's very tedious to select the outer edge, is there a short cut of doing that process?

Hold down Alt when selecting an edge - it will select all "connected" edges.

Thank you, Christopher!

Tricks to get this to work:

Apply object scale then extrude.

Select vertices/edges around the edge of the plane/circle and extrude.

Change the edit mode select mode to "edges" instead of faces or vertices and select the edges then extrude.

Hope these tips answer your question.


text:
About merging vertex edges of different materials namely plane and cylinder
I wonder if anyone could help me with one issue I have run into while using Blender and modelling my character.
Actually Blender is not merging vertices of hand of my character with wrist properly under subdivision modifier applied at 2 subdivisions in the viewport. when I merge them vertex at merging points distorts and when I merge vertex of plane everything goes fine but when I try to model the hand with a cylinder and merge the hand with the character (a plane), vertices at the merging points distort. I don't know because of what kind of tension or something. editing.
I would be grateful if you could tell me how to solve this problem.

Select all and press Shift N (recalculate Normals, outside).

Thanks brother you have solved my problem. Tnx a lot.


text:
Scaling textures across different objects
Is there a way to keep the checker texture the same size?
Currently it scales with the size of the object, even though the scale in the Cycles node itself is set to 5, a value of 5 looks different across the two models.
I'm pretty new to modeling so I might mess up on some terminology, but is there a node I could use -- that is universal between all objects -- that I can use to determine the size of the texture?
Or how would I make this texture consistent between the two models without manually scaling it down in the checker texture node?

Add Empty to a scene and use Texture Coordinates node with Object type (choose Empty).


text:
How to script a gizmo that would be transformable(move, rotate, scale) independantly from the object it would originate at?
I am looking at the documentation and the gizmo samples that come with Blender(Text Editor's Templates>Python>Gizmo...)

but I am currently struggling a bit trying to understand how this new gizmo concept works.
I would like to make an operator that would make a custom shaped(doesn't matter much - could be other types) gizmo appear at the orgin of the active object and could be moved, rotated and scaled independantly of the object so that I could get it's transformed matrix and do other stuff with it during(or at the end of) the operation. I am sure I will figure it out sooner or later, but I could use some help to make it sooner rather then later and would be very greatfull for it. If somebody could point me to some more examples of gizmos used that would also be awesome.

Hi I noticed you mentioned this is relatively new, I have Blender 2.78, is it only available in 2.8? regardless, if I understand what you're asking and I'm not sure I do you don't need a gizmo for that the bpy already provides a means of doing this.
.BLEND
I hope if it's not what you're looking for it at least gives you a decent alternative.

I want to have a gizmo that would move independently from the object, not to transform an object. By the way, you can just do this instead of so much typing. Anyway, the new gizmos are only available in 2.80. I thought I made it pretty clear by providing a link to the documentation and mentioning how one can see the gizmos working with examples from Text Editor's Templates menu, but I will try to update the question so it is formed clearer and it is easier to understand what I am talking about.

Are you maybe looking for something like this? https://imgur.com/a/jIA7llU The myLocRotScale matrix allows you to edit the location rotation and scale of the gizmo (in World space). In the shown example the gizmo is translated by 3 in the y-Direction. The default value for myLocRotScale could be set to ob.matrix_world.normalized() which is the object location, so that the gizmo appears there until you change it. BTW here is a nice collection of Gizmos: https://blender.stackexchange.com/questions/131685/gizmo-types-in-blender-2-8

Having had a rake through the commit history, it looks like gizmo is just a rename of manipulator.  I'm guessing these weren't exposed through the API before.

Gizmos require a target to act upon.
Manipulating the gizmo will act upon either:

Property
Operator
Callback

These are set by calling one of the following methods:
target_set_prop(target, data, property, index=-1)
target_set_operator(operator, index=0)
target_set_handler(target, get, set, range=None)
The second of these return an Operator Properties object which you can then set.  Still researching this and need to run some tests but I believe that the second one is what you are looking for.  Please see the documentation for these methods
See the gizmo_operator_target.py template for an example using the transform operator.
See the gizmo_operator.py template for an example that performs a more complex operation using the callback method.
Callbacks made easy
It's quite difficult to see what's going on in the template example so I have prepared a simpler version:
def setup(self, context):

    arrow = self.gizmos.new("GIZMO_GT_arrow_3d")

    def move_get_x():
        return context.object.location.x

    def move_set_x(value):
        context.object.location.x = value

    arrow.target_set_handler("offset", get=move_get_x, set=move_set_x)

    arrow.matrix_basis = context.object.matrix_world.normalized()

    self.x_gizmo = arrow

def refresh(self, context):
    self.x_gizmo.matrix_basis = context.object.matrix_world.normalized()

In order to manipulate a gizmo independently you will have to look at the matrix_basis property.
Simply commenting out the last line in the refresh method will leave the gizmo where it first instantiated:
#self.x_gizmo.matrix_basis = context.object.matrix_world.normalized()
If you want to keep the gizmo with the object then you need to update matrix_basis accordingly.
Subclass Gizmo
Another option is to subclass gizmo, unfortunately I haven't had time to write up an example of this but it is another avenue to explore.
You might also want to look at using the matrix_offset to retrieve information about the change.
If this still isn't quite what you're looking for then you can consider using an empty and attach the gizmp to that instead.
You might also want to look at this question.

Thanks for the answer. I know I can use an empty for this in a modal operator, but then I can also use any temporarily created geometry instead of it that can look like a gizmo... I thought gizmos would be easier to understand when I first heard of them... :/ I still have no clue how to make a gizmo that one could just grab and move or rotate or scale...

You can't do regular ops on a gizmo from what I understand, they have 3D representation defined by their draw method, but they don't really maintain their own state, this appears to be done by the GizmoGroup which they're declared in. This is why you need an empty (or some other object), something that can be scaled etc. , gizmos only act on events through their invoke and modal methods

There is always this creative method, not quite what you're lookiing for but could be adapted

@MartinZ I've added an example using the callback method

Playing with Simple Gizmo Template.
Most likely each of the  templates other than the simple gizmo, have more of the functionality desired in question.  Binding to targets, operators, rotation, using custom shapes.
Since the question gif is the simple template, and since you can work it out yourself "sooner or later" here be a hack around with the simple template, to translate a single arrow and keep that transform in a matrix.

In original the gizmo mapped its "offset" to the energy property of
a lamp. target_set_prop  Instead I have given it two callbacks to get and set the
property. target_set_handler  Just like with binding to an operator target_set_operator it allows for changing object properties during gizmo transform.
A dummy 4x4 matrix is set up on the window manager. The arrow
widget sets its z location in position 2, 3.
If there is an object named "Cube" in the scene it assigns its local
matrix to the dummy matrix
A class variable is added to keep track of the context object, so the
widget has starting point at the active object.

import bpy
from mathutils import Matrix

from bpy.types import (
    GizmoGroup,
)

class MyLightWidgetGroup(GizmoGroup):
    '''Tool Tip'''
    bl_idname = "OBJECT_GGT_light_test"
    bl_label = "Test Light Widget"
    bl_space_type = 'VIEW_3D'
    bl_region_type = 'WINDOW'
    bl_options = {'3D', 'PERSISTENT'}
    obj = None

    @classmethod
    def poll(cls, context):
        ob = context.object
        wm = context.window_manager
        return (ob)

    def setup(self, context):
        wm = context.window_manager
        def move_get_cb():
            print(wm.xxxx)
            return wm.xxxx[2][3]
        def move_set_cb(value):
            wm.xxxx[2][3] = value

            cube = context.scene.objects.get("Cube")
            if cube:
                cube.matrix_local = wm.xxxx

        ob = context.object
        mpr = self.gizmos.new("GIZMO_GT_arrow_3d")

        mpr.target_set_handler("offset", get=move_get_cb, set=move_set_cb)
        mpr.color = 1.0, 0.5, 0.0
        mpr.alpha = 0.5

        mpr.color_highlight = 0, 0, 1.0
        mpr.alpha_highlight = 1

        self.energy_widget = mpr

    def refresh(self, context):
        ob = context.object

        wm = context.window_manager

        mpr = self.energy_widget
        if self.obj is not ob:
            mpr.matrix_basis =  (ob.matrix_world).normalized()
            wm.xxxx = [c for row in Matrix().transposed() for c in row]

        self.obj = context.object

bpy.types.WindowManager.xxxx = bpy.props.FloatVectorProperty(size=16, subtype='MATRIX')

bpy.utils.register_class(MyLightWidgetGroup)

It seems it's going to be later in that 'sooner or later'. Seems too complicated for what I wanted to do, I'll stick with temporarily creating another object for now. But I i'll also keep trying to figure this out slowly and this is really helpful so I appreciate the answer - thank you.

Based on my comment:
Are you maybe looking for something like this?
In this way it is possible to set the Gizmo loc,rot,scale in the global coordinate system. You simply store the location, rotation and scale in a 4x4 matrix and set that to be the matrix_basis of the gizmo. Due to the self-updating nature of the gizmo this can be set at any time, even at the end (see example).
Here is the code: (Mostly the template with added Matrix myLocRotScale)
import bpy
from bpy.types import (
    GizmoGroup,
)

class MyLightWidgetGroup(GizmoGroup):
    bl_idname = "OBJECT_GGT_light_test"
    bl_label = "Test Light Widget"
    bl_space_type = 'VIEW_3D'
    bl_region_type = 'WINDOW'
    bl_options = {'3D', 'PERSISTENT'}
    ########### Modified here
    myLocRotScale = ((1.0, 0.0, 0.0, 0.0), (0.0, 1.0, 0.0, 0.0), (0.0, 0.0, 1.0, 0.0), (0.0, 0.0, 0.0, 1.0))
    @classmethod
    def poll(cls, context):
        ob = context.object
        return (ob and ob.type == 'LIGHT')

    def setup(self, context):
        # Arrow gizmo has one 'offset' property we can assign to the light energy.
        ob = context.object
        mpr = self.gizmos.new("GIZMO_GT_arrow_3d")
        mpr.target_set_prop("offset", ob.data, "energy")
        mpr.matrix_basis = self.myLocRotScale ########### Modified here
        mpr.draw_style = 'BOX'

        mpr.color = 1.0, 0.5, 0.0
        mpr.alpha = 0.5

        mpr.color_highlight = 1.0, 0.5, 1.0
        mpr.alpha_highlight = 0.5

        self.energy_widget = mpr

    def refresh(self, context):
        ob = context.object
        mpr = self.energy_widget
        mpr.matrix_basis = self.myLocRotScale ########### Modified here

bpy.utils.register_class(MyLightWidgetGroup)

########### Modified here
MyLightWidgetGroup.myLocRotScale = ((1.0, 0.0, 0.0, 0.0), (1.0, 0.0, 0.0, 0.0), (0.0, 0.0, 1.0, 0.0), (0.0, 3.0, 0.0, 1.0))

Here the myLocRotScale matrix allows you to edit the location rotation and scale of the gizmo (in World space). In the shown example the gizmo is translated by 3 in the y-Direction (see the 4x4 matrix in the last line). The default value for myLocRotScale could be set to ob.matrix_world.normalized() which is the object location, so that the gizmo appears there until you change it.
BTW here is a nice collection of Gizmos: Gizmo types in blender 2.8

Thank you for you answer. I am really sorry about not foreseeing this misunderstanding, but I thought it would be possible to transform the gizmo by user interaction, not programmatically. I should have been more specific.

@MartinZ Thank you for clarifying! So if i understand correctly you want to make it possible to move the gizmo around by simple user interaction, which is achieved by enabling this gizmo interaction by programming in python?

@MartinZ I think the easiest solution to achieve what you describe would be to use an empty with the gizmo you want and then add a line of code in python which sets the transforms of the gizmo (similar to my answer above) to the transform matrix of that empty. Then you can manually scale move and rotate the gizmo indirectly while still having the gizmo functionality.

I don't need a gizmo for that. The empty itself is enough then. I could have any geometry instead of the empty as well so it can look any way I want as well without a gizmo. I use an empty for this here . I was hoping it can be done with a gizmo instead of creating another object - I mean what's the point of gizmos if you need to create another object anyway?.. It might be possible with target_set_handler though, but I haven't figured out how that could work.

@MartinZ While an empty might be enough here, the method i described would still be needed if you want to use the gizmo visual appearance and also want the slider and mouse-clickable behaviour of the gizmo. But if you do not need the actual gizmo but only want something to keep track of transforms, then an empty will do just fine. (BTW concerning the project you linked: Even if you would find a way to do what you want without adding another object such as an empty, probably then the "snap to vertex" would stop working)

I'm a novice in Blender, but as I know, in common - gizmo is a "read-only" property, that represents hidden parallelepiped with sides: MinX(Object)-MaxX(Object), MinY(Object)-MaxY(Object), MinZ(Object)-MaxZ(Object).
So You probably can create standard box, make it hidden and push your object inside.

Hi, I appreciate you trying to help, however as far as this answer goes I am afraid this not helpful at all. It does not convey any information regarding the matter the way I see it. I'll down-vote the answer as this is definitely not something I would like to award with 500 point bounty and I am afraid I do not see it as useful. I am talking specifically about these gizmos. You can see them working if you try the examples in the Text Editor Template menu.


text:
Cycles smoke not responding to wind
I made some dense smoke in cycles with the Quick Smoke simulation. I want the smoke to be blown to the left of the scene as if it's coming out of a smokestack, so I added a wind force field. No effect. I turned up the strength, still no effect. I even added another wind force field, yet the smoke still stubbornly rises straight up.
How can I get the smoke to respond to wind?

Wind Falloff
The force field in the scene is being affected by a high dampening due to the simulation of gravity introduced by the Falloff settings you are using. The wind is now acting as if it was dragged down by a strong force that is currently erasing its influence on the smoke.

If it is suitable for your project, my suggestion would be to simply come back to the default value of Falloff Power = 0.

This can also be caused by the force field being on a different layer than the smoke domain.


text:
Flame attribute for cycles smoke not working
I'm trying to follow this tutorial to make a realistic smoke simulation in Cycles: https://www.youtube.com/watch?v=oSiV5gg_lCs
I followed his node setup to a T, yet when I plug in the flame attribute into the emission node, my uv sphere doesn't light up like in the tutorial.
Am I missing a setting somewhere?

Figured it out!
The problem was that I was changing the Smoke Domain object to Flow Type: Fire + Smoke instead of the emitter object, the UV sphere.


text:
Cycles render showing up black and weird
I'm trying to make an awesome render of an office building in Blender 2.7. Here's what it looks like in my 3D workspace view so far.

I've been toiling over the wire frame and 3D aspects of it, and then checking to see how it actually renders periodically. When I first started, it seemed to be rendering just fine. But then, when I was about 25% of the way done with building my model, I clicked render and this weird black image of it shows up.

Also, I'm quite certain that it doesn't have to do with the lighting, as I have 4 lamps placed around the scene. I'm starting to get a little concerned that when I'm all done with pouring hours into this, I'm not going to be able to render it properly. Does anyone know what might be going wrong?
edit: I tried adding a white material to the floor part with the chairs on it, but it showed up like this:

Here is the .blend:

Have you recalculated the normals yet? Also, what sorts of materials do you have applied?

what material do you have on the building?

There are no materials yet, and I don't know how to recalculate normals or what that does. I'm a beginner, so could you tell me please?

About normals - http://blenderartists.org/forum/showthread.php?114883-The-Recalculate-Normals-command. Could you upload your blend file using http://www.pasteall.org/ or http://blend-exchange.giantcowfilms.com/ because some parts of the model on render seem to be overlapping each other and it's hard to say what's going on.

sure thing.

The problem is that your entire building has a material on it "realistic glass"

Take this off and viola problem solved. If you would like to put glass on one part of the mesh see this question.

Wow, you just solved all of my problems! Thank you so much!

No problem... if it's solved, click the little check mark next to the answer so we can close this case. thanks-


text:
How to fill in spaces between voronoi holes?
I'm trying to model a scene with bone tissue, like in this pic:

I've gotten this far, but I need those nice, rounded holes like in the pic above.
I've ALMOST achieved this effect by going into edit mode, selecting the whole thing, and hitting "Smooth" in the Transform toolbar on the left a few times. But it deforms the part where the bones meet up with a space, as shown here:
How do I get rid of those spaces and make the bones join up smoothly?

Edit: Also, here's the blend file for the first screen shot:

Have you tried a subsurf modifier on img 1?

Just tried it, and I'm still coming up with the same issue.

Can you upload the .blend for img 1?

You should sculpt some forms like these then duplicate them around and deform with lattice for variation. It would be the fastest and prettiest method and you would be done by now.

Check this blend here:

For geometry like this, I often use the Skin Modifier, because it can create these smooth branches automatically. But to use it, you need a mesh as a base, not a bunch of curves. So first, remove the curve profile from your geometry:

Next, use Alt + C to convert the lines to a mesh geometry:

In Edit mode, remove doubles, using a high threshold value, to merge as many vertices as possible while still maintaining the shape you created initially. I was using a merge distance of 0.1 for your scene:

next, add the skin modifier (can take a while until it is on there, and save your scene before):

Finally, go to Edit Mode, and select all vertices, then hit Ctrl + A. This activates a modal operator, when you now drag the mouse you can scale the profile up and down. Scale down until the branch thickness is what you like, and then add a Subsurf Modifier to smooth out the skinned mesh:

You can scale each point individually using the shortcut I mentioned before, so variation can be created easily. You might however get some areas with artifacts. Sometimes, marking a different vertex as the root can resolve or at least improve it:

Now play with the thickness:

How do I control merge distance when removing the doubles? I click the "remove doubles" button and it does its magic without giving me any options. If I say "okay Blender, have it your way..." and continue on though your instructions to add a skin modifier, it adds a bunch of faces on only one voronoi hole.

@League14 You can hit F6 RIGHT AFTER running any operator to get the options, or look in the so-called 'last operator panel' in the Tool Shelf on the left.

Here's an alternative and easy way, based solely on modifiers: Start with a simple cube.  Add a subD modifier, and give it 5 iterations to create a cubic sphere.  Next, apply a Cast modifier to make it perfectly round (just use default settings).  Then add a Decimate modifier using the Planar option, and give it 3 iterations (based on the 5 iterations of your previous SubD modifier).  Change the Angle Limit to 20, check ALL BOUNDARIES (very important), and make sure Delimit is set to Normal.
At this stage, with all the modifiers in the stack, your cube should appear to be a Voronoi sphere (or roughly spherical in shape).  Add another Cast modifier with default settings just to get it as spherical as it can with the given edges currently on the object.  Now add a Wireframe modifier.  Set thickness to 0.1 or so.  Finally, add another SubD modifier and give it a couple iterations until you're happy with the results.  Done.


text:
When I use array modifier to the bezier curve, the last part of the curve was not covered

I was trying to make ice cream, the array object doesn't cover the full curve, whatever I do the last part is not covered. I tried scaling, deleting the last vertices of curve but none covered till the last segment.

could you share your file so that we understand what's happening?

Since your shape is uniform along length, consider using the star as a bevel.
Then you don't need the array modifier, and you have overall better control.

Convert your star shape to a curve (Mesh > Convert to > Curve)
Select the spiral, and choose your star shape as a Bevel object
Adjust to your needs

If you fancy some ice-cream, you can taper it, too ! :)  Either with Alt-S, or a taper curve

Is it slipping off the other end? Try GX.


text:
Has anyone found a way to animate hair particals manually?
I understand you can simulate the hair, but that's not what I want.
It's too laggy, takes too much time, and I never get the results that I want.
The ideal situation I would like would be to select my subject, switch to particle edit, then scrub through the animation combing the hair to where I would like it to be and adding key frames for it.

I don't think combing animation is possible, but you can guide the hair with curves. https://www.youtube.com/watch?v=vu6MQC6qdRY

You cab try to use keyed particles with hair system. This gives a rather cumbersome system, but you can at least TRY.


text:
Splitting Sections off an Object
I'm trying to make a simple 3D house with doors, roof, and stairs, I made all of it from the same cube so it would all line up perfectly-ish.
My trouble is I have no idea how to remove sections of it from the block so I can set the material and textures how I'd like.
So for instance, I want to make the doors out of wood, and not have the entire house look like a door.
Thank you.

Does this answer your question? Assign material to part of mesh

When you do get it split up and start animating doors etc, you might find this useful when you come to move the entire house around the scene, rotate it, etc.  The separated components will want to stay behind.  -  https://blender.stackexchange.com/questions/166114/partial-rotation/166148#166148

I'm not sure if you're asking how to assign multiple Materials to the same Mesh or how to split one Object into two.
If you just want to Split a Mesh into two, the easiest way is to select all faces you need, hit "P" and then click "By Selection".
To create a 2. Material go to the Materials Tab and hit the "+" icon. Select all  the faces you want to share this Material and then hit "Assign" in the Materials Tab.


text:
Imported .FBX file from fusion opens with multiple dotted lines and empties, I can't remove them without changing the objects' allignments
After adding joints on my model, I imported it as an .fbx file into Blender 2.8 to create an assembly animation.
But when Blender opens the file, there are multiple dotted lines which are centered in point, also there are lines (I found out they are called "empty") that I can not remove without messing up the positions of the objects.
I removed the joint in Fusion and tried again, but they're still there.
Do you know how can I fix this problem?

The dotted lines are relationship lines. They mean that one of the object is the parent of the other, which in turns means that if you transform (move, rotate, scale) the parent object, all its child objects will have the same transformation applied.
You can "unparent" objects by selecting them and then using either :

The shorcut ALT + P then choosing "Clear and keep transformations"
Object (top or bottom bar of you 3d view) > Parent > "Clear and keep transformations"

Then, the relation lines should disappear and you can freely delete your empties.
I would advise selecting ALL your objects in the scene and unparenting them all at once while keeping their transform.

thanks! doted lines dissepared but the lines (right side of the image) are still there, do you know the reason?      thanks again

Do you mean the crosses ? They are the empties. They are a conceptual object which can serve as parent for example or to transform other objects with certain tools in blender. If they are unparented you can simply select them and delete them with the "x" or "del" key

when ı select and delete them all the objects move somewhere else, but ı unparented them just as you said, i don't get why it doesn't seem to effects it

Could you upload your file on https://blend-exchange.giantcowfilms.com/ and paste the link in your question so I can look at it ?

I'm doing an internship in a firm now so unfortunately i can't share the files :(

Could they be relationship lines? Removing dotted assist lines? Problem only occurs when Appending!
If you're using 2.8, the option is on the top right of your 3D window with a drop down arrow next to a symbol with two circles interlaced.
Good luck OP :)

thank you very much!

No worries :) I literally searched for that yesterday haha. First time I'm using 2.8 and hadn't used blender in years, feels good to be modelling again. Remember to pick one of the answers as accepted so that people know this thread has been resolved (;


text:
1 model for unity but 2 files in blender?
I have an orb that I made in blender, and I want to make a floor underneath it. Should I make it in the same blender file as the orb, or should I make a new one so I will import both files into unity and put them together? I'm thinking about when I will texture the models. What will be the best method?

Im Speculating that the orb wont just lay there on the plane, but maby gets some animation or interactive behavior.
The Blender file format is treated as an Prefab in Unity. Editing it further, adding scripts, components, rearranging, etc or unpacking it breaks connection and therefore the benefit of quickly updating edits from blender to unity vanishes.
Therefore I'd suggest a seperate .blend file for the floor or even exporting the active selection as .obj or .fbx and overwriting the coresponding objects in the unity asstets folder manually if you want them in the same .blend scene for better refrence (animation, modeling, etc.)


text:
My symmetry is off but only on the lower jaw of my model?
I am making a Chimpanzee skull and everything was fine until a few moments ago when I started to work on the lower jaw, I realized that the symmetry was off even though I didn't mess with it.
Does someone know how I could fix it?

Replying to josh,
I think I did everything that you said to the best of my ability but now there seems to be another problem. (probably something I did wrong).

There now seems to be a point next to the jaw if you look to the right.
I can click on it but don't know what it is.
Is there anyway I might be able to send you the file and you could look at it?

If you apply the remesh modifier you may be able to get rid of any floating geo that may be giving you problems, recenter the objects origin point to the center of the mesh then continue sculpting.

(I am the person who originally posted the question but had to make an account, as I was unregistered when asking the original question)
I am replying to @josh sanfelici, this is what happens when I go into edit mode and then select mesh, then symmetry.

This happens on the jaw, (I did ctrl z it since I don't think that was supposed to happen).
I did see earlier that there was an orange little dot and it didn't seem to be in the center of the jaw. I don't know how it moved or how I can even put it back.

Select in edit mode one vertex which is exactly (or nearly) at the center of the jaw, then press Shift S (cursor to selected); then in object mode with the jaw selected right click and choose set origin (origin to 3D cursor), then try to use the symmetrize function. Shift C to put the 3D cursor in the world center again.

After checking if the origin of the object is in the correct site (which should be where you want the center of the mesh, typically the world origin when sculpting), you can go to edit mode, mesh menu, and choose symmetrize. In the bottom left black panel you can choose axis and direction of the symmetry.

At a glance, it looks like the lower jaw is a separate object (correct?) and that the origin of that object has been accidentally moved somehow. In Object Mode, select the jaw, right click, and go to "Set Origin". You should see a few options; select "Origin to Center of Mass (Surface)". That should get your origin back to the right place and fix the symmetry.


text:
Why lightmap_pack change uv1 and uv 2
I'm a new python developer. Recently I want to make a script to add a new UV for model and using lightmap_pack to unwrap. it works great but i found the uv1 is changed with lightmap_pack. Why?
import bpy
from random import random
from math import radians
import sys
import os
import os.path
import string
context = bpy.context
objects = bpy.context.scene.objects
for obj in objects :
    if obj.type == 'MESH':
        context.view_layer.objects.active = obj
        obj.select_set(state=True)
        mesh = obj.data
        if len(mesh.uv_layers) < 2:
            mesh.uv_layers.new(name='lm')
            lm = mesh.uv_layers.get('lm')
            bpy.ops.object.editmode_toggle()
            lm.active = True
            bpy.ops.uv.lightmap_pack()
            bpy.ops.object.editmode_toggle()
print('start to export')

Edit:
I found that if the mesh have child mesh, the parent mesh uv2 and uv1 will changed at same time,
but is there is only one mesh lightmap_pack will only affact uv2.
How to deal with this?

Using lm = mesh.uv_layers.get('lm') or mesh.uv_layers.new(name='lm')  will give you the old one if it exists, or a new one named "lm".  The way it is above will keep adding "lm.001" , "lm.002" , ...but you will always only be operating on  "lm".

I'm tried to this ：lm =mesh.uv_layers.new(name='lm.'+str(meshIndex))
meshIndex+=1  but it's same result.

if the mesh have child mesh, add a uv2 for each mesh and use lightmap_pack to unwrap. the parent mesh's uv1 and uv2 will changed. i only want to change uv2's unwrap.

My point being If you want to use the new one use lm = mesh.uv_layers.new(name='lm')  there is no need to "get" it as well  Its name will depend on the existance of "lm", "lm.001" etc. .  To make sure it is the one named "lm" use get and if its None use new.  The way you have it in question code is wrong.  This  explains why first one is the one always being used. Re the child mesh, edit question.  In particular explain what you mean by uv1 and uv2 (i assume it's where they are in uvmaps collection? .. where first is uv1 = uv_layers[0]?

`import bpy
context = bpy.context
objects = bpy.context.scene.objects
for obj in objects :
if obj.type == 'MESH':
context.view_layer.objects.active = obj
obj.select_set(state=True)
mesh = obj.data
if len(mesh.uv_layers) < 2:
lm = mesh.uv_layers.new(name='lm')
lm.active = True
bpy.ops.object.mode_set(mode="EDIT")
bpy.ops.mesh.select_all(action="SELECT")
bpy.ops.uv.smart_project(island_margin=0.05)
bpy.ops.object.mode_set(mode="OBJECT")
lm.active = True
`