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How do I model and animate a twinkling star?
I am building a scene with Blender in which I need to depict a multi-colored
twinkling star, rising on a vertical path, and disappearing at clipping plane
just above it.
I have done it in POV-Ray, which uses scene descriptive language. Is there a
utility to export from POV-Ray and import into Blender? Should I write a Python
script, or can it be done in Blender?

"multi-colored twinkling star" could be interpreted many different ways.. Could you add an example (perhaps a render from povray)?

How do I attach a zip file to this forum?

You can't, you'll have to use another host and put a link here. I was thinking of an image or a short video/gif though..

I can see that your an Adept. Send me an address at        spaceshaper@hotmail.com and I'll send you a 30 frame clip.

Blender allows you to generate a Noise modifier for animations. This could give you a "twinkling" effect if you apply the noise to a material's value such as Emission, Intensity, Transparency, etc.
First, mouse-over the value you want to apply noise to. In this example I'm using Diffuse Intensity.

Then press I to add a keyframe. If it works, you'll see the button turn yellow.

Open the Graph Editor and click on the channel used for controlling the Intensity.

In the Graph Editor, open the Properties panel by either pressing N or selecting View >> Properties. Under Modifiers, click Noise. This will give you a set of controls to manipulate the pseudo-randomization of the Intensity. This works on any value that can be animated, including colors.

Since then an Import feature had been added to POV converter Blender tools.

While there is an addon to use pov-ray to render from blender there doesn't appear to be any recent attempts to import pov-ray files into blender. The best option appears to be poseray which can read pov-ray and save as obj which blender can import. I'm not sure if it handles animations.
As for doing your animation in blender you can animate almost every value available. This means you can animate the colour of the star or the amount of light it emits as well as it's movement. With the mouse over a value you can press I to keyframe the value or right click and select Insert Keyframe.
If you are referring to the star being composed of multiple colours then you can assign a different material to each polygon in the star or you can use an image to control what colour appears where on the star.
Of course if you prefer a text based approach there is nothing stopping you from writing a python script that creates and animates the star. This might be a steeper learning curve though. Blender's python documentation includes a quickstart and an overview to get you started.

I will explore 'poseray'. I will then continue learning python.


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One material with different color per mesh?
I just started a project width a lot of colored pencils in it.
As I want to have all of them have the same Material, but a different color, i came up with the question:
Is there a way to create a single Material und assign different colors to meshes that all have this one material assigned?
Or:
Is it possible to link the materials of the pencils, so if I tweak one of them, the rest will have the changes applied, too?

Yes, it's possible. Do you want the colors random or user defined?

Oh thats great, I would prefer user defined colors.

See http://blender.stackexchange.com/q/8845/599 and http://blender.stackexchange.com/q/8319/599

source: Stack Exchange

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

sort: votes


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Black reflection on glass
I'm trying to render a glassy flac. The problem is, taht it makes black reflections on sides or corners. I don't know where these reflections come from, almost white world and in the example the flac is in white cube and still there is black left side.
What can I do to get rid of these black spots?

I think this is not reflections, but due to refraction! What value did you set for the "IOR" value of the glass shader? I suggest you to try with a value closer 1.0.

I used 1.51714 as suggested here link. When I get to 1.2 it's almost gone, but also some of desired details disappear.

http://blender.stackexchange.com/questions/2558/how-to-illuminate-the-darkness-inside-glass-objects-in-cycles

These are probably shadows from the light.  The only way I've found to get rid of this is to disable them.

Looks to me like a combination of total internal reflection and not enough transmission bounces. Note that this is in someways correct, as if light bounces around inside a piece of glass far enough, it will be absorbed pretty much completely. See e.g. these images

there is an article about rendering fluid in glass I will advice you to read: http://blog.gregzaal.com/2013/10/19/fluid-in-a-glass/

In the render properties for cycle find the Light Paths and increase the Transmission value till the dark spots go away.

I had the same issue and found it was due to my glass being shaded smooth. I added an Edge Split modifier and the black areas of refraction went away.

Use transparent instead of glossy when the glossy ray depth is grater than the value of max glossy bounces.

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

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


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removing shadows between layers
Wow, I got excited when I finally gave up and got help with this problem. I found the exact solution on a previous post:

The question was how to keep the shadow of an object in one layer from being casted onto another object in another layer. I wanted to keep the shadow of layer two from casting onto the object in layer one, so I figured it would be done as so:

The problem is that it did't work. I've spent hours trying to select every possible combo of buttons and scouring the web and I can't get it. I need to quit being like a stubborn mule sometimes and know when to get help. Any of which would be much appresh.

whoops, this might help. Using cycles in 2.71

Ok, I kinda got it to work. Seems to every now and again to not work. Could be a bug. Either way, when it does work I try to press the right layer and exclude buttons so other objects in the fourth or 5th layer don't have any effect on the other layers and blender throws a hissy. So i don't know what I'm going to do about that. Please help

I know this question is old, but in case you still want an answer, is it possible you could upload a .blend?

I don't think I can load a file because I don't have enough points or experience or however they gauge your rank on this page. I don't see one anyway.

There currently isn't anyway to upload files to this site, you'll have to use another hosting site like http://pasteall.org/blend and post the link here.

Ok, I downloaded boomerang6_ja12.blend to that site.

Hm.. looks like a 0 byte file :/ Also in the future remember to put the URL here ;) Pasteall names files with an incrementing number, so there is no way to tell where it is with just the filename.. (I guessed it this time by uploading a file and then changing the URL to the previous file, which happened to be yours..)

Ok, I re-downloaded the file. It should be at http://www.pasteall.org/blend/32340

The file seems to work for me, but I'm not to sure what you want it to do.. Anyway, I'd recommend avoiding extra renderlayers whenever possible, as they increase render time. I think you could take advantage of material index masks here.

Thanks. I had heard of these magic material index masks before and checked it out just before I finished the project. Don't know if I have that kind of time to put into the project. I write and do CG as a weekend warrior to promote books and build franchise. If I get more time I will check it out. Thanks again ;)


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Exporting Animation from Blender to C4D
I hope you are doing well! I am reaching out to all the C4D/Blender GURU's for help on a specific matter that I cannot find on Google...
How do I export this animation? As a vdb? I've tried .fbx. and alembic but they aren't transferring to C4D.... I can't find anything online about how to take a project like this with all these shaders and nodes and now animation, and turn it into vdb files so that I can then load that vdb into my render's volume option... any advice?
(I somehow managed to make this after 6 attempts lmfaooo)
https://www.youtube.com/watch?v=XWv1Ajc3tfU&list=LL&index=3
but now I don't know how to get the vdb... I wanted to import it into my scene in C4D and render everything with the render engine, Arnold, that I have.... Do you know how to get vdb from something like this? If not, I can just make it work in after effects and export as png sequence (found another tutorial for Blender animation render stuff) but I'd really really like to use the Arnold engine and this work flow would be perfect if I could get passed this hurdle...

Hello and welcome. Please don't write in all caps in the title or body of any posts, it is the written equivalent of shouting, is harder to read and may be considered rude. Please use the [edit] button below the post to change you text into regular case.

If you use geonodes to build geometry, you need to place a "Realize Instances" node at the end so that the mesh "exists" instead of being virtual. Then you can export as alembic.
That being said, you will probably not be able to export the material anywhere. Anything beyond a Principled BSDF with bitmaps is pretty much not exportable.

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


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How can I make shading like this?
I'm learning to make models. And I really like this shading style. I can understand the program at a basic level (at a level where I can do toon shading), but I don't know how to make the shadows edge on the model soft and look like they used a low-opacity paintbrush.
Like this

This is the model I have. I have tried making the bushes in this link. It make the shading close to what I want. But I don't understand how it happened.

What have you tried as far?

Sorry but I haven't tried anything yet. Because I don't know what to do or what tools to use to do it. I'm not sure if it's because of the polygon or shading.

The look there is greatly influenced by the model itself. What models do you have?

I have a low polygon tree model.

It would improve your chances of getting help if you at least shared some screenshots of it. If possible, you could even share the .blend file itself using Blend-Exchange. It would also be helpful if you could define the goal a bit better - is it animation you are after, or stills?

Sorry, at first I didn't know how to add it hahaha. Now I've edited and added pictures. I have tried making the bushes in that link. It make the shadow close to what I want. But I don't understand how it happened.

It's called NPR: Non-Photorealistic Rendering. I think that's the only common denominator between the first and 2nd image in the post.

The shadows in the first picture look softer than I did. I'd like to know how to make the shadows look like that. Maybe I need to do something to the model?

I forgot to answer this, I'm after a stills.


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How do I get rid of the seams after merging these two objects?
I merged two objects and each object had teeth that fit in with each other. However, after merging them the teeth are still visible and if you rotate the object you can see light between the teeth (indicating they don't fit perfectly). How do I get a perfect fit and remove the seam?

Maybe you need to remove them manually, but could you please share your file? https://blend-exchange.com/

added the file to it

I later saw this and found https://docs.blender.org/manual/en/latest/addons/object/bool_tools.html to work well.

In my opinion there won't be any magical trick, you can use a series of tricks like for example select all and M > Merge by Distance (with a Merge Distance of 0.0005 m), deselect all and top bar > Select > Select All by Trait > Interior Faces and delete the faces, select all again and X > Limited Dissolve:

Also remove these edges, dissolve some useless vertices, remove some floating edges, etc:

Select these edge loops and AltF:

Then X > Limited Dissolve:

When you have finished one side, symmetrize, etc...

Try selecting all items you want to merge and press Ctrl + J. Or you can right click and select join.
I later ran into issues with this in the same way. Using Bool Tool seems to work as expected without fixing the merged object. https://docs.blender.org/manual/en/latest/addons/object/bool_tools.html

That is how I joined it. But it leaves the seam.


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How do I change the dimensions of an object without affecting the dimensions of an interior window?
I have a rectangular object that measures 265.3m wide x 74m tall. That rectangle has a window cutout within it that is 51m wide by 40m tall. I am trying to resize the 265.3m width of the rectangle to about 75m. However, when I change the X dimension (under Options > Transform) the size of that window shrinks in width as well. How do I change the width of the rectangle without changing the dimensions of the interior window cutout?

Oh, it looks like the interior window dimensions are still 51m x 40m but why does it appear smaller???? Or, maybe I am wrong?

Are these different objects or part of the same object? If different objects, is one parent of the other?

Why the window appears smaller although it is still 51 × 40 m: If you scale an object in Object Mode, it is changing the outward appearance so to say... the underlying mesh is still keeping it's original size. Also the other wall is still 265.3 m in Edit Mode, although it is now maybe 75 m in Object Mode. To let the new scaled down size become its "original" size that will also show in Edit Mode, you have to apply the scale, i.e. so that it stays 75 m but the scale values now show 1.

If you only want the wall to get smaller and the window cutout to stay the same - and I assume from your question, the cutout is not done with a Boolean modifier using a spearate object for the size of the cutout - then you have to do it in Edit Mode.
There are different methods to achieve this goal, at least five which I will show you here:

Moving the outer vertices by a certain distance,
moving them with snapping to a separate target object,
scaling with snapping to a target,
scaling them down (in Edit Mode) by an appropriate factor or
scaling up by new size, then scaling down by reciprocal of old size (or vice versa).

First of all, no matter which method you choose, you have to do them in Edit Mode (press Tab to switch into Edit Mode).
1: Moving by a certain distance
The original wall has 265.3 m in X direction and you want to size it down to 75 m. That is a difference of
$$265.3-75=190.3$$
i.e. you need
$$\frac{190.3}{2}=95.15$$
on each side if you want to move the vertices evenly on each side. So select the vertices on the left border of the wall, to move them to the right they have to be moved 95.15 m in +X direction.
To do this, press G X 95.15 and then Return to confirm the action.

Another possibility would be to click into the Transform > Median > X field and instead of replacing the value, type +95.15 behind it and press Return. You also could have replaced the value with a calculated new one, but Blender can do the maths for you.

The best thing about this method is: Blender can do all the maths for you. It does not matter which way you enter it:

$\text{old value }+95.15$
$\text{old value }+190.3/2$
$\text{old value }+(265.3-75)/2$

As long as it is mathematically correct (brackets where needed for example), Blender will give the correct result for the transformation.

For the right side you repeat what you did for the left side, only this time you have to use the negative X direction by simply typing a minus before the value: -92.15.
Of course you do not have to make it half the size difference on each side, instead you could also move one side 100 m and the other 90.3 m, just as long as it sums up to 190.3 m.
2: Moving or scaling with snapping to a target object
To do this, add a new object (best might be a cube) which is 75 m wide in X direction. Then switch the wall to Edit Mode and select the vertices on the left side. Make sure you have the Snap To options set to Vertex and Affect > Move (and for method 3 later) Scale are enabled.

Now press G X to start moving the vertices towards the additional cube. Hold down Ctrl and move the cursor towards the top or bottom left corner of the cube to make the vertices snap to a cube vertex and then left-click or Return to confirm the action. Repeat the same for the wall vertices on the right and the right side of the cube.

3: Scaling with snapping to a target object
Instead of moving each sides separately, when the cube is exactly placed in the center of the left and right border of the wall you could also scale them down to the desired size.
To place the cube in the center of the wall borders you can select both sides in Edit Mode, then press Shift+S > Cursor to Selected. Adding a new cube will place it at the 3D cursor, i.e. in the center between the walls.
Back to the wall in Edit Mode, with both sides selected and the Snap To settings set like mentioned before under method 2, press S X to scale them down in X direction, hold Ctrl and move the cursor to the nearest cube corner to make the walls snap to one side of the cube. Then left-click or Return to confirm.

4: Scaling down by an appropriate factor
Since it is easy to calculate a ratio between two different values, you could simply divide the desired length by the original length to get the scaling factor. That is
$$\frac{75}{265.3}\approx0.2826988$$
which you can then simply enter when scaling on the X axis.
So select the outer vertices and type S X .2826988 and then Return. Of course it is completely up to you how exact you want this value and how many decimals you need to have an acceptable approximation to the desired width.

5: Scaling up by new size and down by reciprocal of old size
If scaling by an approximated value is not exact enough for you, you can again let Blender do the maths for you. Unfortunately it is not possible to enter a scaling value in the Transform sidepanel in Edit Mode, and scaling with S X does not allow entering the formula 75 / 265.3 as a value directly.
Whenever you enter the forward slash key / while scaling, Blender switches to "reciprocal mode" I would call it. So whatever numbers you entered, Blender will put a 1/ in front of it (and it does not matter if you first enter numbers then slash or vice versa or even inbetween).
This means: if you wanted to enter the formula normally by typing 75/265.3, this will be changed to 1/75265.3. In the same way both /75 and 75/ will be switched to 1/75.
But still we can use those two values to get the new size, because
$$width\:\cdot\frac{75}{265.3}\equiv\:width\:\cdot 75\cdot\frac{1}{265.3}$$
and we just have to perform two scalings succesively.
To do this, you select the outer vertices of the wall and first scale them up by the new size with S X 75 and confirming the action. Now scale them down with the reciprocal of the old size by typing a slash before (or after) the value: S X /265.3 (or 265.3/) and confirming with Return afterwards.


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How can I speed up rendering an animation with Cycles?
I started to render an animation (of 200 frames), using 1000 samples, at 1920x1080 pixels, of a scene including a fog object and mesh files  (from Alias).
It took almost 10 hours for 1 frame, so I think that something is wrong. Is this a usual amount of render time?
I want to keep the quality as high as possible.
I'm using Cycles rendering with CPU, because when I try to use GPU, Blender shuts down.
Specs:
AMD Ryzen 5 3600- 6 core processor
16 Gb RAM
GTX 1660 SUPER

Depending on the complexity of your scene and the precise render settings you’re using, it is certainly possible for a single frame to take 10 hours to render. (A brief internet search suggests a single frame in a Pixar film can take even longer than that during particularly resource-heavy sequences.) It’s hard to say whether or not anything abnormal is happening without more information—perhaps you can upload your .blend file?

my blender file is too big to upload here, my file is almost 1.8 GB..

With a file of that size, it's not too surprising that rendering one frame is going to take that long!

I uploaded my ifle , as you said , , it's not too surprising..! okay got it

File size alone cannot account for the long rendering time. Fog objects are hard to render (try removing the fog object and see how much time it shaves off), and I think it would be wise to figure out why you cannot use your GPU. Your Nvidia card has CUDA support. Have you tried installing the latest drivers for it?

Yes I updated my graphic card.. I'm trying to find what is the problem with my GPU

I'd recommend you use the GPU. Blender probably shuts down because you didn't set it to use the GPU at the preferences tab. Go to Edit > Preferences > System > Set it to the GPU you use, NVIDIA is CUDA, AMD is OpenGl. Other things you can do is optimize the amount of bounces in Render Properties > Light Paths > Max Bounces.

The OP mentions that if they use GPU Blender crashes.

I am aware @Joachim , which I why I asked him to try to set up the settings at the start.


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Transparent object shadows in volume material [Blender Internal]
Currently I am fighting with lighting artefacts within a smoke simulation, when the lightsource is within the volume and especially also within a transparent object within this volume. (Note this question is about the old Blender Internal engine, not Cycles).
Basically I can show the problems with a simple demo setup:

A ground plane which receives shadows from transparent objects;
A container (cube) with a volume material, here a simple, constant density;
A small cube which is transparent so the light can pass out. This small cube is located within the container;
A simple point light within the small cube and thus also within the container and the voumetric material.

This will give you a situation like the following:

Note the following problems:

The floor within the volume is way brighter than outside, as if the volume material has a semi-transparent bounding;
The volume material does not interact properly with the light source (without encasing the light within the small transparent box, it would show up as lit);
The volume also does not cast proper shadows onto the surrounding plane.

Is this a known problem (with Blender Internal)? Is there anything I can configure differently to make it work?
I could not find any option to make the volume material receive transparent shadows; on regular solid shading material, there is such an option ("Receive Transparent" in the shadow pane).

This problem is especially anoying with the smoke simulation, since there the adaptive domain object takes on the role of the volume container, thus creating a dancing bright patch on the ground as soon as some light source moves into the smoke domain.
The only workaround I see right now would be to use light groups and basically clone several copies of the light source...

After a lot of experimentation, my gut feeling says this might be a "bug" or shortcoming of BlenderInternal...
This being said, I'd like to share a workaround (sometimes you're in the unfortunate situation that you just can not switch to the Cycles engine, but have to pull matters trough with BlenderInternal):

the problems arise when other objects with transparent material do intersect with the volumetric material.
thus a partial workaround is to forego such intersections.

In the example shown, we can use the boolean modifier to cut away precisely the intersecting parts. Plus in addition we must take care to avoid fringe artifacts

add a boolean modifier to the cube with the volumetric material. Choose the ground plane as the other object, and switch to set difference operation. For this to work, in the case of the plane (which has no volume), we also need so switch to the "carve" solver (default ist "bmesh").
next we need to apply the modifier. The cube is now cut such as not to overlap below the ground plane anymore. To avoid problems with ray intersection solving, we should move up the cube by 1 blender unit.
Then add again a boolean modifier to the cube with the volumetric material; just this time we'll cut out the space taken by the small light cube. Use again the set difference operation.
next again apply the modifire. Then select the small light cube (which is still there, now sitting within the hole of the volumetric cube). Again to avoid problems with inferior/exterior tests, we should scale the light cube down by a tiny amount, so it is always clear it does not intersect with the volumetric material.

And voila, now it renders as expected:

In practice, it can be quite tedious and maybe impossible to adapt this workaround for the case of a smoke simulation. So bottom line, this is a problem and if anyone knows a better solution.....

Blender Internal did have a lot of shortcomings and is now completely obsolete and no longer available in recent versions of Blender. You should mark this answer as the ‘accepted’ answer as I’d be very surprised if there was any further activity here.


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How can I make Fresnel edges softer?
Below is a poorly drawn representation of what Fresnel does to my model: it covers part of it with a hard edge.

And this is what I want to be able to do; this illustration shows the Fresnel with a softer edge:

Is there any way to do this?

Hello, maybe show some pictures of your object, it should not create hard edges, you can also try to put a ColorRamp after the Fresnel, also you could try the Layer Weight, Facing output?

Index of Refraction < 1.0
I was able to replicate your problem by putting an IOR value less than 1.0 in the Fresnel Node

Try bringing in a new Fresnel Node and it should come in with an IOR of 1.450


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Shading problems with object
How can I fix the shading problems in Blender 4.0?
Here are screenshots of the object grid and the place where the shading behaves incorrectly:

Hello and welcome. Please use a title that matches the content of the post. It should read like a question, be descriptive but succinct, unique and identifying, summarizing the problem so that anyone searching for similar issues is likely to find this. Remove anything superfluous, avoid using words like "this", "help with", "issue" or "question about", instead describe what "it" is. Remember, your title is the first thing visitors see, answers you get depend heavily on it. See What is the problem of asking “How do I do this?"

Please verbally describe what your issue is, be specific and and use relevant keywords. Avoid referencing images or links as alternative to words, try to stay away from vague references like "this happens", "issue with", "like so", which make the post impossible to find for someone using search. Instead describe what "it" is, be descriptive, succinct and detailed. It may not be immediately obvious to users trying to help what you mean. See What is the problem of asking “How do I do this?"

As you can see, the bad shading happens exactly at those vertices where 5 edges come together (a so-called E-pole). Very sharp angles in topology tend to cause problems.
In this case, it could be because the edges are not actually at the exact same level. You can fix this by selecting all the vertices on that level (the top surface from which the protrusions extend), pressing S to scale, pressing Z to lock in the vertical axis, and pressing 0 to 'equalize' them.
An option that's probably better is to retopologize those areas.

If a pole is changing the curvature of the surface, then it should be removed or eliminated.
source

The edges indicated with red need to go. The green edges are a suggestion for the middle parts, but for those near the edge of the mesh I can't think of a proper solution (that keeps your quad-only topology intact, at least, and doesn't add extra loops). You can experiment with several options and see what works best.
The article from which I quoted has insightful tips and options. Here is another helpful thread on BlenderArtists.

Pressing S 0 to scale all vertices on some level without constraining the scaling to a specific axis (for example Z which seems appropriate in this case) will make all vertices be put in the exact same location, not just the same level.

Thanks, @GordonBrinkmann! I had completely forgotten that important step :)

Dont forget your supporting edge loops! even if your floor is perfectly flat, it wont shade correctly with smooth shading without supporting edge loops. example


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Close lots of holes with "virtual duct tape" or by "balloon inflating"
I have a mesh (one object) that I created by unifying a lot of other objects (Boolean Modifier). However, the modifier did not quite worked out on some places which leaves me with a mesh with a lot of holes.
These holes are not always just simple edge loops and there are a lot of them. Here are two examples:

These are only parts of the object. The shape of the whole object is somewhat similar to a bucket (with a lot of holes).
Is there a way to close these holes in a simple way? It ist not really relevant to close them nicely, they should just be closed.
When I would have such a mesh in reality with something like paper, I would simply duct tape those holes. Or, another way: Put a balloon inside the mesh/bucket and inflate it (similar to a bicycle tire, where the inner tube fills the casing). Is there an equivalent for these techniques in Blender?
Edit: Following the comments, I want to give some more details about the model. First, I want to make a house out of cookies. The result should be 3D printed. Therefore, I have a base mesh (from Thingiverse/phrxmd) of a cookie which I piled up (I intentionally did this manually like I would pile it up in the real world by hand). Then, I wanted to merge all these cookies together with an underlying base mesh into one object to be able to print this properly. I did this with the Boolean modifier. However, it does not work out quite well:

Sometimes the "Union" operation did a "Difference" and vice versa.
Sometimes the inner geometry of the cookie was not removed very well.
It was impossible to union all cookies at once with the cube (Boolean Modifier → Union → With Collection) since it ate a lot of RAM (>60GB).

So I did this partially (unify a bunch of cookies into bigger objects and unify this with the cube, manually removed the inner geometry) and got the geometry in the pictures above.
To demonstrate the whole process, I have attached a model that is simpler than the original one but should show the problem:

Hello it's hard to guess your topology, maybe share the object itself, but I guess it will be easier to model it again

You can fill the holes in Edit Mode (select 2 Edges, then press F). This will be a pain. Also painful: Shrinkwrap Modifier on a large subdivided quad sphere... Also painful: inflate a cloth simulation system. I'm afraid moonboots is right: it would be best to watch some topology and general modeling tutorials and then start over again.

Have to agree with @moonboots.. if you can clue us in to the  desired result , then maybe one of us can come up with another way of modelling it.

Thanks, I have edited my post according to your comments.


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Functions to remove extra faces & fix normals? | Marvelous Designer FBX to Blender Workflow
[edit] Here's the project file:
While I realize that the answer may be staring me in the face, I've also sunk a lot of time into this with no real progress.
I'm working on using custom Marvelous Designer clothing for Character Creator, and am using Blender (ultimately) for clean-up & efficiency adjustments. While I'm able to export an FBX from Marvelous that has each fabric as a separate object, the hang up is that those individual pieces seem to have two layers of faces or vertex groups with faces connected in weird ways... and when removing duplicate vertices, it doesn't really clear up the face issue.

What I'm left with are wonky normals and a mesh that cannot be smoothed out. I know the appropriate workflow is to simply retopoligize; but I wanted to check if anyone had a solution to the weird face groups and/or normals issue.

[Edit] The solution turned out to be in part, update my blender from 2.83 to the latest LTS. In that case, I was able to use 'Shift+N' to resolve most of the face issues. There is still a lot of manual work to be done.
I did come across another odd case of Marvelous designer clothing, when imported it looked like this:

The file itself was a lot cleaner. All the faces were set with the normal orientation facing inward, which was easy to correct. But even afterwards it still had the odd issue.

In this case, it turns out that the solution was in the material settings. I switched the blend mode to opaque and checked backface culling - I didn't need the transparency since that can be expensive to render in-game.

The end result:

AFAIK you can create 2 layers of fabric in MD to give the cloth some thickness. So there are often 2 mesh layers, one for the inside, and one for the outside. (But I've also seen cloth models with only 1 mesh layer.) The mesh parts are usually not merged and loose. In best case the meshes do not overlap. But it looks like they do in your case. In Blender you don't need 2 layers. You can delete the inner mesh parts. Select one vert & press L to select the whole part. Then X to remove. Keep only the outer (blue) parts. Finally, just add a Solidify modifier to give the cloth thickness again.

Hello and welcome to BSE. can you share your blend file https://blend-exchange.com

@Blunder It did export two layers with some of the fabric pieces which I was able to remove this way, but it still resulted in this outcome.
I will have to try different export settings from Marvelous though to see if the results vary. I'll keep the thread up-to-date on what I find.

@HarryMcKenzie Here's that link: https://blend-exchange.com/b/y874XoQk

@BluViolets i took a look and you could select all and press Shift+N to make sure to recalculate Normals. Then unfortunately for the rest of the weird red patches of overlapping faces, there is no automated way to fix them, you have to manually go through all of them and delete the overlapping faces and then readd faces.

@HarryMcKenzie thanks! I updated my blender from 2.83 (what I'd been using when starting this project) to the latest LTS and recaulculating normals finally worked for me as well. Still not sure why it wasn't working in 2.83, but I am relieved that it's working as expected.


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How to make bottom of the cube narrower if there are edges in the middle of it?
So, I'm quite new to blender, I am not very familiar with all the terms, so, please bear with me. But I've encountered a rather confusing problem here, since I do not know how to search for the solution in this case.
First I start with inserting a cube. And then I switch to edit mode, select the bottom 4 vertices, press S, and y to scale in the y-axis. And drag towards the middle:

This works perfectly as I want.
But if I extrude at the top, and then I do the same,

By selecting all the 4 bottom vertices:

By selecting all the bottom vertices and the middle ones:

How can I achieve the same effect as I did without extruding anything?
One way I thought is by bringing together first, and then split the figure using Ctrl+R. But I have some figures that I've already done all the extrusion and editing with them, and it would be a pain to recreate them.
Edit:
The so-called "accurate" method seems to also cause some issues.

There is a slight bend where I have pointed above, which is exactly what I want to avoid. This was performed after selecting the bottom 8 vertices into the group.

I thought increasing the accuracy would help, but blender crashes.

Fast but limited method
You can do it approximately using proportional editing:

Use  MMB scroll to change the radius of effect while in transform:

You can try different falloff types like Linear or Sphere, but eventually they all will squish the center of action more than the far side of the radius.
Slow but accurate method
Create a deform cube around the area you want to deform, then add a Mesh Deform modifier on the original cube and set the deform cube as target:

Then select the original cube, ↹ Tab into edit mode, select the vertices you don't want to stay in place, and hit ⎈ Ctrlg to assign them to a new group.
Put that group in the modifier, hit the bind button, then switch to the deform cube in edit mode, and scale down the bottom vertices:

Once you are happy with the result, hover the modifier and hit ⎈ Ctrla to apply it.

Nice ideas. I already tried the inaccurate method with my other figures, but it had caused many other vertices to misalign and cause problems. I like the accurate way. Nice.

What do you think about my question? How do you think I can improve the next ones I may ask? What details are important to be included in these blender questions?

@Exampleperson For the inaccurate method I would try setting the Falloff to Linear instead of the default Smooth as shown here, that's at least a bit less inaccurate. And of course limit it to the Y axis (or restrict it from the Z axis) so that the middle edge doesn't come down while scaling.

Still, there seems to be some degree of misalignment there in the accurate way. Why is that, and any way to overcome that? Especially when the edges that cut the cube are not really in the same place in the front and the back, if you understand what I mean.

For example, it seems to be a bit oriented to the 2nd example in my question. Increasing the accuracy just crashes my blender. My blender is the latest release.

Selecting all the vertices of the original cube into the group helps, and seems to be more accurate. But the top vertices also move.

Also, I found that making the mesh cube as the same size as the original cube gives the best results. But still there is some kind of tiny issues in the bottom of the cube, etc.


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Pink textures when changing textures of object
Pink textures when applying image to object. Absolute or relative path doesn't work. Find missing filed doesn't work too. I am 100% sure that textures exist and on the right path.

Since you are 100% sure, what are we supposed to say? The only thing I can see is in the top screenshot, there is no path in front of the texture name. In the bottom screenshot, there is a texture with the matching name. But I have no idea if the file path is the same so that the texture can be found.

Hi Vlad. Can you try setting in your material the Base Color >> Color Space to sRGB? It is odd that it shows as a blank option. This could be due to a broken or invalid image file. If that's the case resave your image file or try with different image format.


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Transparent image shows black in viewport
Im not the best at blender but I've been hacking away at this issue to no avail. I have a transparent image as a texture in blender but in rendering it shows with a black background... I've researched the issue a lot and I will link the methods I've tried down below as well. I'll attach a video of my blender too so you can see what the issue is.
Additional info: All of this was imported through pc2 export from CLO3d, I'm on a Mac and im using Eevee
Already tried all of these node setups:
https://artisticrender.com/how-to-use-alpha-transparent-textures-in-blender/
Add a transparent image on top of a material
Texture with transparency becomes black
EDIT: Added the pngs I used

Hello could you please share your file (remove all the useless parts and pack the images)?

There is something strange in your video - the Image Texture node has the Alpha settings greyed out as if they were not available... usually even on an image without alpha transparency you can change those settings... so maybe uploading your file would be a good idea. By the way, the "How to set up a material for transparency in Blender" section of that artisticrender site is nonsense. With the Principled BSDF node it is not necessary to mix it with a Transparent BSDF node by the alpha channel as factor, but I noticed you did not do that in your video anyway.

@GordonBrinkmann I have tried using the image compiled in the pc2 zip from clo3d as well as a separate file with the exact same image as png and it comes with the same results. I'll add both of the files in an edit.

Well, this site is focusing on tools and addons shipped with Blender, I have no idea what this pc2 export from CLO3D does. At least I know now why the alpha option is deactivated in the texture node: you have modified the image (intentionally or accidentally?) in Texture Paint mode and not saved the changes. The other thing is, I don't know which render engine you are using, but the Material Preview (which is visible in the video) always uses Eevee. Therefore you have to change the Blend Mode in the material settings to something else than Opaque to get alpha transparency.

@GordonBrinkmann YOU GOT IT THNAK U SO MUCH I HAD TO CHANGE THE BLEND MODD TO SOMETHING OTHER THAN OPAQUE

The second answer in the link Texture with transparency becomes black which you had posted yourself in the question would have given you that solution already.


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How to obtain a sort of "spherical fall-off" displacement?
I created two node trees that extrude a profile (a mesh made up of a few vertices, transformed into a curve, and to which a fillet is then applied to round the corners).
They extrude it in such a way as to create a three-dimensional effect whereby the farther from the contour of the profile, the higher the elevation of the points within the shape.
The red scooter in the figure uses a node based on volume. It creates a pleasant "spherical" shape, but the topology leaves something to be desired because it is a volume converted to mesh, so it is approximate.

The green scooter, on the other hand, is created by intersecting the profile with a grid, then the position of the points on the grid is altered based on their distance from the edge. But in this case, the appearance is angular because the distance increases linearly.

I would like to be able to obtain the soft shape obtained in the red scooter, by modifying the node that generates the green scooter and make a sort of "rounder fall-of". I imagine there is a mathematical function that allows this and an associated node, but I do not know what they are. How can I do it?
Please see the example file

UPDATE:
I continue searching for an answer. Through experimentation, I discovered that using the Math node with the square root operation (and multiplying by a factor to regain the lost height) enables me to create a rounder/fatter displacement. Observe the right side of the green scooter in comparison to the left side on the screenshot below. It is undeniably smoother, but it is still not sufficient. A method to better control the roundness would be advantageous. I have experimented with Map Range and Color Ramp in various configurations, but something seems to elude me.. There must be a better way. Please help.

Another update
Using Robin Betts kind suggestion I tried to use Blur Attribute node. Result is interesting but still far from the red scooter shape.

Might a Blur of position help, somewhere along the line? It's a bit of a fuzzy method, too, though..

@RobinBetts please see my updated question. I tried your suggestion


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Extrude vertices along an axis using geometry nodes, an elegant way
I want to extrude a set of (unfilled) vertices along one major axis.
I somewhat managed to do that converting it to a curve and using that curve as the profile curve for "Curve to mesh" node, the principal curve being a curve line for which I can control the resolution.
To extrude in the Z axis I don't need to rotate anything (contro-intuitively if you ask me), but if I want to extrude along X or Y I need to to rotate the profile curve. I do that in an hackish way, found by attempts and errors...
What is the sane, elegant, beautiful way of doing this? Thanks

PS: I wanted to attach the example file depicted above, but I am still trying to understand how to do it
Edit: Here is the file, but I hope the screenshot is clear enough
Example file

This is how I'd do it, though it's not clear if you want to e.g. support multiple axes extrusion, and if you want the profile to be rotated then, or maybe you would like the extrusion direction to be automatic based on the normal of the profile (though not filled profile has no normal, so it would be a guess about the direction...)

Thanks for taking the time to help me. Your solution works perfectly. It supports multiple axes extrusion as well, something I did not expect, which is very useful. You mentioned, 'maybe you would like the extrusion direction to be automatic based on the normal of the profile.' Yes, that would be very good, but as you mentioned, in a profile without faces, there is no way to calculate a normal... or is there?

@crucchi you can fill the verts as I do with the convex hull, merge by distance to ensure just one face, read the normal of the face. However, the normal could point in the wrong direction. You could maybe get the direction from the order of indices… In such case you could also calculate the normal as a cross product of offset v0→v1 × offset v1→v2.

So, this was your intention regarding making a guess about the direction... It makes sense. I suppose I can assume the default direction is the positive X (or Y, or Z), and if I want to go the other way, I will fill the (now) single "Extrusion amount" input with a negative number. Many thanks, I greatly appreciate your help

it seems there is a problem that escaped our attention. The top object, the one extruded along the X-axis, is also rotated around the X-axis by some amount


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Simulate Shader to RGB in Cycles
I currently have a material  working in Eevee, that contains a Shader to RGB and a Color Ramp to achieve shadows and light in my scene. I want to know if I can transfer this to Cycles because I have to export the model.
Here are screenshots of the Eevee and the Cycles views, so it is easier to understand what I mean:

Click image for larger version

Related, with some nice explanatory answers: https://blender.stackexchange.com/q/223902/35559

But can it be possible to simulate the effect? I want to export the model but it doesnt have any texture because of it. Do you know a way that i can export my model with textures?

I believe that's a 2-step process, baking out Shader to RGB  results in the tree, wherever they are, and then re-combining. I could be wrong, though.

I really am a noob in blender, so im having a hard time understanding this. What do you mean by baking out shader to RGB results in the tree? bake the different colors one by one?

Yup.. wherever there was a Shader to RGB, bake that branch to  to a texture, and feed it back in. I'm hoping I'm wrong.

but the thing is, to make the texture of that object i just used one shader to RGB. i need to make 3 shaders with 3 different colors? sorry im really new in blender

Can you share a representative file on  https://blend-exchange.com/ ?

I´ve made another version of the texture but to work in Cycles, but either way i cant bake it... It only gives a black image when i try to bake it in diffuse mode, i dont understand what im doing wrong to be honest.


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How to make this soft drink material?
I have been making a Fanta bottle model. I was working at the material of the soda, and the reference picture and what I made don't look similar:

And here is the shader I used for the soda:

Please provide more details, such as what exactly you don't like about your shader.

The Fanta on the left is a pack-shot, strongly back-lit, and not refracting any dark regions of its environment. And.. real-life light can bounce infinitely many times around the material without terminating in black. If you share your file on https://blend-exchange.com/ , we can try ways of addressing those differences.

Yes it looks more like a problem of lighting than material


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Apply Geometry Nodes Modifier that has instances of lights
I recently made this very handy randomizer for a tri-lighting setup in geometry nodes:
https://www.youtube.com/watch?v=xwjFmnY-d6M
However, when I discover a seed that I like and want to apply it, I get an error saying that there are no meshes because the lights aren't meshes.
Is there by any chance another way to get the light setup to be realized for further manual manipulation?

Hello and welcome. Instead of having users go through links and external sites please use the builtin tools to embed images in your post. See How to upload an image to a post? or GIF

https://blender.stackexchange.com/questions/247271/geometry-nodes-and-light

Thanks for that resource! It's still unfortunately not working. Any possible hints as to why? https://i.sstatic.net/Hl9a53lO.png

(Using Blender 4.2.1)
An approach is to split the original GeometryNodes modifier in two GN modifiers:

The "Model" is computing and storing attributes. It is making a mesh and it can be applied to freeze a configuration.
The "View" is adding lights based on position and attributes stored by the "Model". It can not be applied because it is not making a mesh.

Follows an example (NB: two screenshots were superimposed to make this figure):

Model GN:
1. 3 vertices of an icosphere are drawn randomly ; others are deleted.
2. The Seed parameter of the RNG is controlled by the GN input panel.
3. The index to pick instances in the "Lights" collection is randomized and stored as an attribute named "light" (see dark pink nodes).
View GN:
4. An Instance on Points node is used to spawn lights picked in a collection.
5. The Instance Index parameter is recovered from the attribute "light" stored at step 3.
6. The Position to place a light and to orient it is recovered from the points generated by the "Model" GN at step 1.
A bonus is that after the "Model" GN is applied, lights position and attributes can be adjusted in Edit Mode as for any regular mesh:

Go to the menu entry Mesh>Set Attribute to modify the value of the attribute highlighted in the Object Data Properties panel for the selected point(s).
Resources:
(Blender 4.2.1+)

Side note: The Seed parameter can be stored also as an attribute if you want to keep its value at hand even after the "Model" modifier is applied.

Thank you for this technique—I will have to give it a try!


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Rigging armature and parts
I am trying to make an animation with a custom skeleton.
I initially have a model sculpted in 3 different parts. I joined all the parts, cleaned them up, and added the bones. Then I did an automatic weights to bind the mesh to the bones.
But a few parts don't react the right way to the animation.
The first picture is the initial pose. Every piece is in the right place.

The second picture: when I open the upper bone, two of the teeth don't stay in place:

The weights are correct, so I don't know how to correct this.
If you could point to me to the right direction, it would be really helpful.
The result, after implementing the solution by moonboots:

For teeth, as you don't want any deformation of these objects, and they should only be part of one vertex group, instead of parent With Automatic Weights, you should better parent With Empty Groups, for the moment the mesh has as many vertex groups as you have bones but no vertex has been assigned to any ofthese groups, then select the teeth and assign them to the group they should be part of:

As you can see, the vertices of your teeth are part of 2 different vertex groups, Tongue02 and UpperJaw, they should be only part of UpperJaw:

You need to select them all and remove them from Tongue02:

Or select all the upper part, remove from all group, then assign to UpperJaw:

Ok, I just tried that. But I don't really know what to do next tho
When I go to Pose Mode after putting all the vertices to vertex groups, and try to manipulate, nothing happens....
I feel like I am missing one step....

Please share your file

Here is the file....
https://we.tl/t-kCHUVV1MSX

I've edited my answer   @lostsf

Ohhhh! Thank you so much! I will try that tomorrow and get back to you! Thank you! I just can't believe that little vertex was making the entire mess... Thank you for spotting it!

It's not this vertex, it's all the teeth vertices, I'm just showing that if you select one of these vertices it shows that it is assigned to 2 vertex groups

yihhhaaaaa! thank you so much! it actually took time make a clean re-grouping. But it works! I am so happy!
thank you thank you thank you!


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Unexpected roughness in the rendering of a flat surface with Blender render
I made the following object. I use the Blender render engine and the basic configuration of the cube material is given bellow.
As you can see, the top face of the cube is rendered rough, and I do not want this. Is it possible to make it appear as the front face, for instance?
Thank you in advance for your help.
Vincent

It looks a bit like Z-fighting. Make sure you don't have any overlapping faces (See http://blender.stackexchange.com/q/5441/599).

You are right, thanks! I solved the problem by removing the top face of the cube. Now, it is rendered correctly but I do not see a top face in the 3d view… where is the face that is rendered? (I have checked that no object is hidden on the 3d view)

It might be hidden in edit mode (Press Alt+H, in edit mode). If that doesn't fix it, is it possible you could upload the blend?

Yes you are right, it was hidden in edit mode.
Problem solved, thanks again.


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Extract particle age info as render layer
[.blend file here]
The problem
My problem is related to node editor and multiple render layers, as far as I'm concerned. I have a simple particle emitter and an icosphere serving as a single particle object. Thanks to the Particle Info node I can easily get the info about particle age. But what I want is to render some kind of alpha channel map (or B&W bitmap) based on particle age info, where only particles of certain age are visible. The math part is not a problem for me. I can combine some math nodes to filter out the value I need. The only problem is how to extract this to the compositor (in parallel with the rest of the scene)?
My current node stack for the particle object looks like that:

The "what I'm trying to achieve" part
My big goal is to render an animation of welding sparkles.

I watched a few videos of some real ones and noticed that most sparkles at the end of their life usually emit something like a small glare. Here's an example:
YouTube video
If you pause the video you'll notice that some sparkles at the end of their life emit a 'subset' of smaller sparkles for a fraction of a second. I want to emulate this with a glare node but unfortunately it is only available in the compositor. What I'm missing is a separate render layer (aside from the whole scene) which consists only those sparkles which are about to die.
Completely different approach
Maybe I'm doing everything wrong and maybe there are some other ways to achieve such effect? Please let me know if you have better ideas.

You can do this by adding a new render layer with an Override Material specified.
First create a dummy object and give it a new material and call it something like particle_age.  Just plug the Particle Age output into an Emission shader and plug that into the output.  Also make sure to give it a Fake User.

Then just add another render layer and give it the new material as an Override Material.  You can also override the samples with a small amount, since emission shaders are easy to compute.

That's exactly what I was looking for! Thank you very much.


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Help! can't get simple compositing of render layers to work
I saw an answer to this exact same problem, but it was in 2.69. I tried it in 2.71 and it doesn't work. I've tried to blend the two objects using a simple color mix box and an alpha over box and neither would work. I've seen tuts using 2.6x and 2.5 and neither of them worked although a hybrid of the two got me to this simple attempt that I think I'm close to. I would like the blue color band on the boomerang to glow using a blur node.
thanks,
TP

It doesn't look like either of your images have any transparency, so alpha over isn't going to do anything. Try making the sky transparent (how to do this depends on whether you are using BI or cycles).

OMG! Thank you. I have been chasing this like a hound dog for a week, scouring the web for tuts. and going through every one of them I thought would help, but all of them were pretty old (2.5 sometimes). I have posted this on another forum and loaded my files on them and struggled and struggled and no one noticed or indicated that I needed to have the images in a transparency. Aaahhhh!!!! Once again, thanks.


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How to set max scale on instances based on scale of other instances
Good morning/afternoon/evening/etc Blender Family
Forgive me if my question is not immediately clear.
In short, I am trying to use geometry nodes to create a system where the Z Scale of instances on a set of points is changed over time with noise, and then the maximum scale of those instances is "remembered" and applied to new instances which are spawned on a copy of the original points.
It might be helpful to think of the old digital graphic equalisers where they have a peak meter which shows the peaks for a second or 2 after the previous max level was reached.
See the opening seconds of this old tutorial using Animation Nodes by Chris P.
https://www.youtube.com/watch?v=mjYf-tD2SqM
I don't want the peak scale to be remembered for just a few seconds.
I want the peak scale to be remembered and maintained until such time as a new maximum is reached.

I can get the scale from the first set of instances and scale the second set accordingly, but I can't figure out how to get this working in simulation nodes.

Before you point out my ignorance - I do understand that the scaling I am applying in the simulation zone is being animated over time and is not the result I am looking for. I know that I need to use attributes somehow, but I can't figure it out.
Any help would be greatly appreciated.

Everything before a Simulation Zone is locked at frame 1. For all other frames, it uses the output of the zone. That's one issue I'm seeing.


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Baking Image Textures in Blender yields black image for some parts
I'm the same guy that posted the issue earlier with the sword that wouldn't bake correctly. The question was poorly phrased and would've required too much explanation so I've just gone and made a different weapon and isolated the problem. If you take a look at the screenshots you'll see that I used Image Textures to color parts of the "weapon", which is different from the image texture that I use to bake the weapon.
Problem is, it seems like any parts with this color image texture attached to it (not the baking image texture) turn out black after getting baked. Anyone know why this is, or what could cause it?
For reference, I'm using Cycles on diffuse bake with only color selected. I noticed in the output section below baking there is something that says Target: Image Textures, and it has a "clear image" button below it. Does that affect anything or do anything important?
Any help would be greatly appreciated and I will be available all today to provide further clarification if needed

I have actually just SOLVED this question myself by messing around. It appears that if youre using image textures, and decide not to use them, you need to remove them from the shader area instead of just disconnecting them. If you don't remove them before you bake then blender will take the existing bake and paste it over the image you used, thereby massively messing things up.

Hi. Please use a title that matches the content of the question. It should be descriptive but succinct, unique and identifying, summarizing the issue so that anyone searching for a similar problem is likely to find it. Remove anything superfluous, avoid using words like "this", "help with", "issue" or "question about", instead describe what "it" is. Remember, your title is the first thing potential visitors see, answers you get depend heavily on how insightful it is. See What is the problem of asking “How do I do this?"

If you have solved the question, post it as an answer yourself, rather than editing the answer into the question (don’t think “Reddit”). Other people may find this information helpful.


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Things doesn't work
Something has screwed up my mesh. Build vertexs and move them doesn't work. I am not able to see the mesh in vertex paint. Parts of the mesh get selected as one part. I have no idea what caused this. See the mesh, my settings and say what i got to do. When i delete vertexs, more vertexs get deleted then selected. Draw colour in vertex paint doesn't work.

Hello please share your file: https://blend-exchange.com/

the Snapping tool is active (magnet icon). It can mess up other vertices when you edit the mesh.


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How to import character
This is Lolly Poppings. She are Czech and tough. Czechs are analytic, prize friendship and drink the most beer.
I created her in 3D with Blender to export her to Akeytsu. This is a 3D animation software and I am going to create a animation with Lolly Poppings.
When I export and import her to Akeytsu things get messed up. How do I export her successfully as she looks in Blender?
I searched after how to do this on other sites but I didn't found any information to how. There is no other solution then you telling me how to solve this. I post screenshots and my file so be gentle and solve this. Blunder you mean that i don't need other export settings. The mesh need retopology and will after not be messed up in Akeytsu. The retopology i did make the mesh lose colour. How do i keep this from happening? I duplicate vertex's because i am not able to mirror things with mirror modifier. How do you create a right part of a left part with mirror modifier?
Blend file:

Reference Image
Model in Blender

Blender Screenshot 2:

Blender Screenshot 3:

Blender Export Settings:

Akeytsu Screenshot:

Hi there! You did a great job to match the reference. But the mesh is in a very poor state. It's really broken and has everything a good clean mesh shouldn't have. It has holes, inverted normals, overlapping and intersecting faces, wires (=loose edges with no faces), duplicated vertices, and no edge flow at all. It's also a nightmare to work with. You need to do a retopology first to create a mesh with nice topology


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How to create mouth
I create 3D meshs in Blender to import them to the 3D animation software Akeytsu. I need to create a mouth that open and close. A mouth that has teeth and cavity in it. How do you create a space in a mesh? How do you create a animation mouth? How do you fill a circle?
In a animation a character has the mouth closed, mouth closed with teeth or open the mouth with teeth. You need a opening and how do you create it? The mouth got to be at the lowest part of the head. The teeth is put in the opening. This character has the mouth i got to create. https://www.nukeygara.com/akeyschool/getting-started/sky-surfer-character-demo It doesn't need to be as advanced but be similar to this mouth. You move the openings edges, hide and don't hide teeth. When a human open the mouth, it's something behind the teeth. How do you create it? What more is to say? You know how a mouth looks when a human is talking. I need a tutorial or other information to create such mouth.
Tell me how to do this other things so i don't need to post more threads. How do you see vertex paint of every part of the mesh? Now i see vertex paint of one part at a time in vertex paint mode but otherwise i don't see it. I added a circle and don't see it in solid mode. How do you make a circle you added to a mesh you see?

Hello your question is too broad, could you please show how your head looks like?

Hello, Rebourne ...We don't have enough to go on here. We definitely need a look a your existing mesh, and a clear indication of how you want your mouth to look. Please edit to include these details, then this question will be answerable, we'll re-open, and do our best for you.

you need try shape keys to deform your character. To create mouth you can use sculpt Grab or Elastic Deform.


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How do I remove all internal edges of a converted font to mesh?
I have converted a font to a mesh and I would like to just have the outline.  I need to delete all the internal edges without going through all the pain like the image below.  The red arrow is a manual delete of one edge. I want all the internal edges gone. Is there a quick solution?

Let's focus on what you want to achieve and not on how. This means asking the question from different perspectives, one being:

"How do I get the outlines of the Glyphs as mesh edge-loops, quickly?".

The result is the same.
As a script
Run this from the Text Editor with the Font object active and in Object mode.
import bpy

obj = bpy.context.active_object

def convert_to_mesh_outlines(obj):
    bpy.ops.object.convert(target='CURVE')
    obj.data.dimensions = '3D'
    bpy.ops.object.convert(target='MESH')

convert_to_mesh_outlines(obj)

Manually
If you aren't comfortable with running scripts, the following steps are the manual analog of the above.

Add your Text
Convert to Curve  (Alt+C in Object mode will give the Convert to menu )

Notice the highlighted tab changes from F (font) to two dots with a curve (Curve).

Set to kind 3D (yes makes no sense - but you will get an outline immediately)

then Convert to Mesh

You may use Limited Dissolve option. In Edit Mode select the whole mesh (A), then press X-->Limited Dissolve.

You may need to remove some remaining edges manually though.

You can press Alt and Right-click twice on the border to select it, Shift+Alt+Right-click to add subsequent edge loops to the selection, Ctrl+I to invert the selection, then X> Edges to delete all the interior edges:

too much work and likely to miss edges.

@zeffii I think the gif shows how quick and easy it is.

In the scenario of only one character, i'd agree. Any more characters and i'd be going for a simpler solution.

Select all (A)
Select external edges: CTRL + E -> Select Boundary Loop
Separate selected edges into a new mesh: P


text:
Where is my Displacement Map?

My displacement map seems to have disappeared...anyone know why?

Hello and welcome, you need to explain more about your issue in order to understand your question

Without any further information on what you did, how should we know what happened to your displacement map? Apart from that, a displacement map usually is a texture, the part of the settings you are showing in the screenshot holds no information about textures. Or do you mean the settings how to handle displacement (Bump Only, Displacement Only, Displacement & Bump)? They are only available for Cycles, you have set the render engine to EEVEE.

The Displacement settings are only available in Cycles render engine, for the moment you are in Eevee.


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How to apply subdivision surface modifier to this cube without artifacts?
I'm trying to make a simple ramp shape with a cube. I applied a bevel modifier to a single edge, then another bevel to all edges, and finally a subsurf modifier to make it smooth. However, the subsurf causes artifacting. I know this is due to the underlying geometry, but I don't know what the most efficient way of fixing this is.
I'm trying to understand the flow of this shape because I'm working on a python script to make it for me (for learning purposes). Currently I've just disabled the subsurf modifier, as it looks okay without it. In the future though, I want to figure out how to produce that shape without artifacts.
Any ideas?

I think you should be OK with just the two Bevel Modifiers - the first one with the weighted edge (highlighted below), and the second with default settings. Shade Smooth afterwards to make it smooth without the need for a subdivision Surface Modifier (which almost certainly will cause artifacting under these conditions).

That is definitely not a bad result... I know that I can do that via scripting as well, so that's good. Cheers!


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How to offset Geometry nodes rotation while scaling instances?
Here is the thing. I'm making an animation using geometry nodes, and i'm using weight paint to scale some instances:

That, is making this:

This is rotating and scaling but the rotation is not visible because is at the same time as the scaling.
The thing is, i would like to use the same weight to not only make the instances go from 0 to 1, but to rotate the instances while doing this but with a small offset, so i can see the rotation during the animation. At the moment, because the rotation and the scaling is happening at the same time, can't see the rotation.
Here is the rotation:

Here is my Geo node (very simple)

So my question is, anyone knows how to offset my rotation, so it's a bit after start the scaling?
I'm basically looking for something like this but for all the instances and without keyframes:

Your real problem is that you take a float value in range $[0; 1]$, and interpret it as a boolean Selection, which is a common mistake, caused by creating a group input socket by dragging from an empty "ghost" socket to a boolean Selection socket of another node. Press the N key to open the Numbers Panel, change the type to float, and now your animation won't suddenly flip the scales from 0 to 1. Similarly, as the squares now smoothly grow to their size, they will also smoothly rotate.

You can still explicitly convert the float to boolean using e.g. "Compare: greater than 0" node for scale, but using the smooth transition for rotation. And finally, if the transition in the vertex group is too short, you can use a simulation zone to increase the length of the transition.

@MarkusvonBroady you were right, switching to float and adjusting some parameters with a compare and a math node did the trick, thanks. If you add it as answer I can mark it, thanks

Your real problem is that you take a ⚫ float value in range $[0; 1]$, and interpret it as a  boolean Selection, which is a common mistake, caused by creating a group input socket by dragging from an empty "ghost" socket to a boolean Selection socket of another node. Press the N key to open the Numbers Panel, change the type to float, and now your animation won't suddenly flip the scales from 0 to 1. Similarly, as the squares now smoothly grow to their size, they will also smoothly rotate.
You can still explicitly convert the float to boolean using e.g. Compare: greater than 0 node for scale, but using the smooth transition for rotation. And finally, if the transition in the vertex group is too short, you can use a simulation zone to increase the length of the transition (e.g. use the vertex group as speed of change, by which you increment the actual animated value).


text:
Is there a good/industry methodology to setup folders in blender projects?
I need a good way to organize my blender project files in the project folder.  I've tried a universal texture folder (any movement and things get lost), I've tried to include a texture folder in the project folder (lots of duplicates with other projects)
What is a good methodology to set this up and easily transferred to another person or team or GIT.

In industry it works like this: If you are not the boss, you follow whatever structure boss dictates. If you are the boss, you (should) have enough experience to setup such structure.
There is no single best structure, but such answer won't help you. I hope this helps instead:

use version control for your project files (subversion is good for this, mercurial with large files plugin, etc..)
keep all the project files inside the project structure with relative paths. Categorize these files in folders such Textures, References, Rendered, etc. Try to keep the folder structure wide and not deep - like max. depth 2. Don't pack the files into the .blend, because then you need to unpack them to edit. If you need to share project outside the versioned workgroup pack the whole structure into .zip or pack files into .blend.
to the above point there are two exceptions:

large simulation files (caches of several GB in size). These days your work files should live on an SSD, but these caches sometimes need to have a separate archive on HDD because of their size. In this archive have a folder for each project and very large files inside. Version it. Ensure this archive has the same path (drive letter) on every machine and link the files to projects with absolute paths.
things all projects share that should be updated for all projects across - like some addons or scripts. Keep local scripts inside project folder.

also have some library location outside the projects for your materials, textures, light setups, node setups, HDRIs, etc.. Never link anything from this library to the project, always make duplicates inside projects. There could be several libraries and they can be shared. Versioning is not critical, though backing it up once a while is.

After many tries I guess there simply isn't a universal method that just works out of the box with every Blender project (or with any project that involves cooperation) imaginable.
It all comes down to the nature of the project itself. Rendering still images or movies might have different requirements than creating game assets.
The universal texture folder might be a good idea at first glance, but once you start altering those textures (painting seams, baking dirt/worn edges) those textures become project- and even object-specific. So once you make changes to the base textures, you might them store in a project-specific area of your file system anyway.
Subfolders within the project folder keep things organized well enough within the Blender project, but they don't necessarily work for export to game engine formats.
Then there's always a difference between working on projects locally on your Computer, in a local network or over the Internet.
If you work locally on your Computer but still want to share the work with other people, you would at least have to share a method how to set up the project folder (that's nothing special to Blender). The same goes for office-like LAN setups, both should be well-organized.
Collaboration over the Internet is a whole different story. The first thing that comes to mind is "hey, let's set up a git/cvs/mercurial repo". It's a good idea in general although there are virtually no distributed version control systems that deal well enough with binary files out of the box (the only one I know of is Perforce but it's not free and requires good hardware to run well).
IMHO the best method to share your work Blender has to offer without any additional work is to pack external data into the .blend file itself. Once you've done that you won't have to think about what to pack into the repo or where and how to store data in a manner that it would work over all setups. The only thing you have to remember is to clean up your file every now and then.

Great point of view

Mercurial does come with a bigfiles module these days; https://www.mercurial-scm.org/wiki/LargefilesExtension ; they mention a couple non-included options thero too

@StarWeaver - I know. git also has several possibilities, but handling binary data is still not number one priority for all the major distributed versioning systems out there, so one should be prepared that they might not work in some cases.

git works great for text files but for large binary files I stick with svn. With git each user gets a copy of the entire repo, so they have every version of every file which leads to many GB per project, but with svn each user only has two copies of each file, one original to compare with and one possibly modified copy. Only the svn server keeps a copy of every version. And an svn server can be located in another folder on the same machine.

(Speaking as an asset creator in the games industry.)
Short answer:
There isn't one right way.
The long answer:
Of the most useless meetings I have attended in my professional life, folder structure and file naming meetings are at the top.
Everyone has their preferred way, and people rarely agree.
In the games industry there is a significant difference between "game assets" and "workfiles". And it is important that the game assets use naming conventions dictated by someone like a "technical director", or whoever is in charge of the repository.
The workfiles are less important because they won't make it into the compiled build and no two artists will ever agree on a structure anyway.


text:
How to reset viewports camera angle?
Strange question maybe but my viewport camera is skewed on a weird angle.
(like 35-45 degrees) wondering how to fix it.

Hold Shift and press Numpad 4 or Numpad 6 until your camera is at the correct angle.

Thank you, it does rotate it so it helped, but still not perfect, needs another hit of the numpad but with less rotation if that makes sense

you can always go to the default cameras by pressing Numpad 1, Numpad 3,Numpad 7

In the 3D view, press N to show the Properties panel if it's not already showing.
Select the camera object and the Properties panel will show the Location (X, Y & Z) and its Rotation (X, Y & Z).
You can enter any values you want in those fields.
Alternatively, in the same Properties Panel, with the Camera selected, check Lock Camera To View.  Now when you change the view, the camera will be updated.  When you're happy with the angle of the camera, uncheck Lock Camera To View.  Fine tune it by editing the fields as mentioned above.

Go to View and set Lock to 3d Cursor, if your cursor is in center.


text:
Wireframe mode doesn't select everything
I had this feature until I must've clicked on something. But on wireframe mode, when i'm trying to select trough everything, it doesn't..react same way as if it was in solid mode.

You probably disabled X-Ray mode.
It's enabled by default, but can be switched off/on.

YES @JACHYM i feel stupid now....THANK YOU

Happy to help. And don't feel bad, at least you learned something new :).

Check whether you're in edit mode or object mode. If necessary hit Tab to go to Edit mode


text:
How to add a radian property to a panel and have it work?
I'm trying to add the Line art crease angle to my viewport panel. I thought it should be fairly straightforward. When I change it to 180 degrees using the slider control I get this in the console area:
bpy.context.object.grease_pencil_modifiers["Line Art"].crease_threshold = 3.14159

Of course the value is in radians and not degrees, but the slider display is in degrees. All well and good.
But when I place in in a panel thusly:
col.prop(bpy.data.objects["Line Art Thin"].grease_pencil_modifiers["Line Art"], "crease_threshold")

I get a nice control, which has the degrees shown, and I can manually enter the value by typing in it, but the slider control does not work. What is the best way to remedy this situation?

Probable dupe https://blender.stackexchange.com/questions/112196/how-to-make-a-python-operator-as-a-slider-scripting-an-addon/112209#112209

Thanks to batfinger for pointing me to that link. The answer is straightforward:
col.prop(bpy.data.objects["Line Art Thin"].grease_pencil_modifiers["Line Art"], "crease_threshold", slider=True)

It needed to have the slider=True appended.

Possibly worth mentioning that this works because the property is a 'ROTATION' type.  If the scene unit designated to rotations is degrees (default) it will display as degrees.


text:
Sculpting and separating
I am Sculpt mode. Snake hook, scrape and smooth brushes do nothing to the mesh.
How do I move the mesh so I am sculpting?
I selected pieces of the mesh and pressed P to separate them. However the separated piece becomes nothing. The vertex is selected and not everything.
How do you separate pieces you see?
I did apply the subdivision modifier and it screwed up the mesh. Moving the mesh in sculpt mode does nothing anyway. See the mesh and my settings. How do i so it does something when i move the mesh?

Hi. That's hard to tell without more info. Have you added a Subdivision Surface modifier and but not applied it? Have a look here: https://blender.stackexchange.com/q/238582/107598 - if this link doesn't help, add a screenshot of the mesh and the modifiers to your question.

Modifiers work top-down. It's a good idea to apply them from top to bottom. Also note that you can only sculpt the base mesh (=the mesh without modifiers.). This is reason why it doesn't work. I guess your base mesh is only a few edges extruded by the Skin modifier.
Long story short, apply all modifiers: first the Mirror,  then the Skin, and finally, the Subdivision Surface modifier. Now, you can sculpt the mesh. For symmetry you can enable the X-mirror option in the Sculpt mode.


text:
Retopology with vertex paint
I painted colour on my mesh with vertex paint. You are also able to colour the mesh with texture paint, but vertex paint appears easier.When I retopologize with BSurface, the mesh loses the vertex paint colour.  When I do retopology with quad remesher, the same happens. How do I do retopologize with BSurface or quad remesher and keep the vertex paint colour? I added the data transfer modifier. However colour, layer selection one choice is all layers. I see no way to switch it to the layer i transfer from. How do you choose a specific layer in colour, layer selection?

You can't. Vertex Paint assigns a color value to each vertex. When you quad-remesh an object, many of the vertices are removed and replaced, causing the loss of color data.
For instance, consider Bob here:
Bob sports a lovely mustache, along with a mask to conceal his true identity.

As you can see, Bob's face consists of many vertices, contributing to its detailed appearance.

Now, let's quad-remesh Bob, as he's too high poly and slowing down my computer. (Of course, this is just an example)

Oh no! Bob, what happened to your face?

Any vertices that aligned with the quad-remeshing process were retained, preserving their color data.

Ah nice!  I knew you could bake an image texture, or transfer the data some other external way, but I was unaware there was a modifier just for that.  Thanks!

Hi, aidan! It's a funny one, indeed.. I expect it will be absorbed into Geometry Nodes, eventually.

You can transfer Color attributes between objects with similar surfaces but different topology using the Data Transfer modifier:

Above,  a color attribute on vertices, called 'vc_smiley' is transferred to another of the same name from 'Icosphere_Tri' to a re-meshed version, using one of the available mapping methods:

If the modifier is applied, the color will be baked into the new topology.


text:
Model deforms when animating it
I'm very new to Blender and I'm learning how to rig and animate characters so I can import them to Unity. I made a humanoid model and rigged it, but when I try to move its legs the model deforms a lot.
Below are the images of the rig and the modeling deforming when I move its leg, and also the image of the model in edit mode:

How can I avoid this from happening? I'm still new so I don't know whether or not the problem is the model, rig, or both.
Leg being lifted up:

Updated file: Leg becoming flat:

This is my blend file:

Updated blend file:

Hello please share your file: https://blend-exchange.com/

Don't move the leg.  Rotate the leg.

I tried rotating the leg upward but the bottom half of the torso gets deformed that way too

At a quick glance, it doesn't look as if you've parented the top leg bones to the root bone (Ctrl-P > Keep offset) and have you parented the body to the armature with automatic weights?

Yes they're parented with automatic weights, and thanks for letting me know the leg bones weren't parented to the root

apart from the fact that the leg bones were not parented to the first spine bone, everything seems ok, you need to make some corrections though as when you rotate the leg it also moves some vertices of the other leg

Thank you, what would I need to do to make those corrections? Also, is that also the reason why the lower torso of the model gets deformed when a leg is lifted up? I don't know if it's normal or not so I provided extra images

You have inner faces, remove them:

Also change the modifier stack order, put the Subdivision Surface modifier at the bottom:

At last select all the vertices that are not supposed to move when you rotate the upper leg and remove from the upper leg vertex group:

For the updated file, assign these 2 vertices to the UpperLeg.L vertex group and see if it is good:

Hello, I did all these steps and it fixed the issue with the torso deforming! But now when I raise any of the legs the upper thigh of that leg gets flattened. I tested to see if removing the leg vertices from the vertex groups would help but it just messed up the leg even more. Would this be caused by the placement of the bones?

Could you please share your new file?

Of course, I have now added the updated blend file to the question

See my edit and tell if it fixes your problem

I assigned the vertices but the leg still becomes flat, I posted an image of what I'm talking about above the two blend files in the question

I'm talking about the butt vertices, these are the ones you need to assign to the upper leg, anyway it will still look a bit flat because of the way your mesh and your armature are made, if you want it to bend differently you need to make a bit more complicated mesh and maybe add a bone between the spine and leg

Oh okay thanks for all the help


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In the Drivers Editor f-curve, can I prevent keys from snapping to integer keyframes?
I am using the Drivers Editor in my motion capture pipeline. I have already recorded a trial video using facial markers, tracked the markers and converted the constraints on the empties to f-curves. Now I am using the Drivers Editor to control the rig with the empties.

After some initial experimenting, I realised that the relationship between empty and bone movement is not linear. So I started editing the f-curves to approximate the movements of the my face onto the character.
My problem is that, for example, the distance between the jaw closed and fully down is just 17 mm. I would like to insert several keys between these two extremes to easily control the f-curve.

I can insert a key and set its position to, e.g. 10 mm, but as soon as I try to move it in the editor, it snaps to the nearest integer (meter!!!). I have tried moving the key on the y-axis only by entering "G-Y" but as soon as I hit "G" the key position snaps to the nearest integer.

I can adjust the value of the key in the text-box without the key position snapping, but this is not very intuitive. I guess I could also scale the parent of the empties X 1,000, but this would mean setting up a separate 3D viewport to observe and select them.
So, before I proceed too far with one of these strategies, can anyone tell me if there is a way to prevent keys from snapping?

Look at your last screenshot, in the top right side there's a dropdown menu for snapping: now is "Nearest frame". Change it as needed.

Thanks Josh! I honestly thought I looked everywhere for it. I expected there would be a reference to it in the menus. Anyway, do you want to change your comment to an answer?

Full credit goes to Josh Sanfelici for this. I'm just making it easier for others to find. From Josh: 'Look at your last screenshot, in the top right side there's a dropdown menu for snapping: now is "Nearest frame". Change it as needed.'


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Exporting wireframe - freestyle not generating desirable output
I want to do a wireframe render of a model I created, however the freestyle renderer is proving to be of a low quality that ignores many outlines. Compare the two images below. The freestyle renderer simply does not cut it - I want a way to generate a very similar output to the bottom image which represents the model properly. Help is appreciated.

You could try explicitly marking the (coplanar?) edges as 'Freestyle', and including marked edges in the Line Set, so they can be picked up.

@RobinBetts Thanks for the notice! I've marked every face for freestyle and also played with a few settings including making Crease Angle extremely low (0.1d), checking all Edge Types, inclusive negation (under Face Marks), etc. The output is a bit better but not quite desirable. Results here: https://imgur.com/a/DANMpuQ

@RobinBetts Update: My apologies, I got the crease angle the wrong way round. This is the result with a value of 179.9d: https://imgur.com/a/ImVsGP0
Much better, but not quite there yet. Notably, some lines are missing from the thing on the bottom left. Text doesn't contribute to the freestyle and there are some weird lines showing up that shouldn't exist: https://imgur.com/a/XdcIlTE

I think you're going to have to share a representative sample on blend-exchange.com

@RobinBetts Sure! Here's the file: https://blend-exchange.com/b/gEbPm8BD - I have removed a few elements to keep it detached from the associated project but I hope this reflects the situation described above.

I think the problem is logical.. the use of Face Marks  rather than Edge Marks, which behave more in the way you illustrate, I think. Example here with some liberties taken to make WIP more visible. BTW You'll have to forgive me if I'm not quickly responsive today.

@RobinBetts Thank you, looks like that's done it. Result looks good and only needs a few manual tweaks. Cheers!


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How can I remove specific selections from the Instance on Points node for a curve?
I'm making a vine and trying to prevent randomly generated leaves from spawning too close to the start of their parent spline (as well as the branches from spawning too close to the end of the core vine).

I've stumbled on some things that almost seem to work, but the closest attempts all break the random value node—which is way more important. I suspect the operation needs (or, at least, would be easier) to be done before the Random Value node.

Thanks in advance for any and all help!

Edit: Thanks to Chris below for a suggesting a Boolean and instead of multiply.
I figured out a solution. Idk if this is the best way, but it works! I researched and tried so many things before asking. Idk how I managed to make this so much harder than it needed to be...

just a hint: yes, multiply boolean values works - but for readability reasons a boolean math (and) would be better understandable - i think

@Chris Ah, that does make more sense. I've updated my answer. Cheers!


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How can i make a 4 legs spider robot move
I have a problem with the animation of a 4-legged spider robot (picture 1). I'm new to animation in Blender. The first time I managed to animate everything but the movements are too horrible for a robot (picture 2). The second time I managed the movements perfectly but I used a bone for each important part but I can't make it move because I can't use Inverse Kinematics because everything is destroyed, and the main body doesn't move (picture 3).
Can anyone help me arrange the bones and do the animation properly? Please.

Hi. You haven't actually added any pictures, these are just links to files on your computer. Please look at this guide on how to upload a pictures: https://meta.stackexchange.com/questions/75491/how-to-upload-an-image-to-a-post

Add picture #2 and 3.


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Store different clases in a Collection property? (Like a list)
I need to have a collection that stores different classes (would contain only 2 classes specifically).
In other words, is like I'd like that collection to "act" as some kind of (generic) List.
But not sure if it's possible. As the API says, I need the collection to be a subclass of PropertyGroup. In that property group, to store a class object I need to use a PointerProperty (if I'm not mistaken).
BUT, to define that PointerProperty, I must define their class. So is like I'd have to choose the class I will add to the collection (only one).
I saw that both classes derives from bpy.types.bpy_struct, so I thought about defining bpy.props.PointerProperty(type=bpy.types.bpy_struct), but is not possible, gives an error.
The other option I have is to make a PropertyGroup with 2 props; one prop for storing the class A, and another prop for storing class B. And then check if one or the other property is None (so I know which class stores). But this feels wrong.
So, is it possible to have a collection that acts as a list?
Thank you so much for the help.

You can nest a PropertyGroup inside another PropertyGroup using PointerProperty and use that another PropertyGroup again inside another PropertyGroup using CollectionProperty.
import bpy
from bpy.types import Panel, UIList, Operator, PropertyGroup
from bpy.props import *

class CUSTOM_PG_property_group(PropertyGroup):

    text : StringProperty(default='Text')

class CUSTOM_PG_collection(PropertyGroup):

    object : PointerProperty(type=bpy.types.Object)
    label : PointerProperty(type=CUSTOM_PG_property_group)

class CUSTOM_PG_collections(PropertyGroup):

    items : CollectionProperty(type=CUSTOM_PG_collection)
    item_index : IntProperty()

class CUSTOM_UL_collection(UIList):

    def draw_item(self, context, layout, data, item, icon, active_data, active_propname, index):
        row = layout.row(align=True)
        row.prop(item.label, 'text', text='', emboss=False)
        row.prop(item, 'object', text='', emboss=False)

class CUSTOM_OT_collection_item_add(Operator):

    bl_label = "Add a Item"
    bl_idname = "xx.collection_item_add"

    def execute(self, context):
        collections = context.scene.collections

        collections.items.add()
        return {'FINISHED'}

class CUSTOM_OT_collection_item_remove(Operator):

    bl_label = "Remove a Item"
    bl_idname = "xx.collection_item_remove"

    def execute(self, context):
        collections = context.scene.collections

        collections.items.remove(collections.item_index)
        return {'FINISHED'}

class HelloWorldPanel(Panel):
    bl_label = "Hello World Panel"
    bl_idname = "OBJECT_PT_hello"
    bl_space_type = 'VIEW_3D'
    bl_region_type = 'UI'
    bl_category = "Test"

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

        collections = context.scene.collections

        row = layout.row()
        row.template_list('CUSTOM_UL_collection', '', dataptr=collections, active_dataptr=collections, propname='items', active_propname='item_index', rows=4)

        col = row.column(align=True)
        col.operator('xx.collection_item_add', text='', icon='ADD')
        col.operator('xx.collection_item_remove', text='', icon='REMOVE')

classes = (
    CUSTOM_PG_property_group,
    CUSTOM_PG_collection,
    CUSTOM_PG_collections,
    CUSTOM_UL_collection,
    CUSTOM_OT_collection_item_add,
    CUSTOM_OT_collection_item_remove,
    HelloWorldPanel,
)

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

    bpy.types.Scene.collections = bpy.props.PointerProperty(type=CUSTOM_PG_collections)

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

    del bpy.types.Scene.collections

if __name__ == "__main__":
    register()

Thank you so much for the help, I wasn't aware of that