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Is possible to use "snap to grid" when using a camera in perspective?
"snap to grid" only seems to work if I'm using the orthogonal view, if I use it on perspective mode, my objects move way too much.
Or, there is a way to move objects only cm by cm in perspective mode?

Try holding the shift key when moving. It isn't snap-to-grid, but it should slow down your mouse movement.

I know about that but I'm searching for something more aimed at precision modeling


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How do I save a selection of points in a curve in blender 3.2?
Vertex group is not in the object data tab, vertex color is also not there. All the tutorials point that it should be there.
The points in a curve are vertices, correct? So, I should be able to save their selection. Is there something I'm missing?

Would you at least name one tutorial which points there? I've never seen a tutorial where they have vertex groups on a curve.

The  points on a curve are generally not vertices. They are Control Points, encoding parameters to a function by which an approximation of the curve can be generated at a given sampling-rate / resolution. The (visible)  approximation is made of vertices connected by edges.  The resolution can vary.. until it's set, you don't know where the vertices are going to be.  You can store named attributes on Control Points, accessible to shaders / other modifiers.. can you give a use-case?

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How do I make a light show in "solid mode" in the view port?
I want a light to affect the view port when your model is gray; the solid circle in view port shading. The light is only visible in "rendered mode". How do I change that?
Thank you.

Do you just want it to look like solid shading, so is your actual question how to create something that looks similar in material preview or render? Because if so, that's not very clearly explained... Or do you specifically want to view it in Solid mode because the performance while working in the viewport is better with this shading? Well, then I have bad news, the performance is better because it does not take any lights etc. into account, so even if you could make it use lights, the advantage of better performance would be lost.

Solid mode, by definition, does not use lamps. It has simple, fixed lighting, either from a predefinted HDRI or a matcap, in Blender's case. (some other 3D software uses fixed lamps, for example)
If you want lights in the viewport, you should use rendered or material preview mode. That is one of the main distinctions between these modes and solid! The other distinction being materials are used in this mode. If you want rendered mode without materials, you can try switching to a different render pass such as diffuse-direct.

Alternately, if you're using Cycles you can use a layer override to replace the scene materials, as described here: How to quickly do a clay render?

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


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How do I disable the wireframe on the boolean modifier in edit mode?
In Object Mode, the boolean hides what I want to hide, but in Edit Mode, the part of the mesh that I want to hide appears as a wireframe and makes it harder to work on my model. How do I disable that wireframe?

Please add some images so that we can see what you are asking. Blender has a built-in screenshot facility from its Window > Save Screenshot menu and you can then edit your question and add them: https://meta.stackexchange.com/questions/75491/how-to-upload-an-image-to-a-post


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In Blender 3.3, how do I make the arrow keys move in increments with each press instead of having to hold the key
In edit mode, when I select a vertex or an edge, and press "G" followed by an arrow key, nothing happens immediately. I have to hold down the arrow key, and after half a second, the vertex starts to move. This process feels slow and imprecise.
I want to press an arrow key once and have the vertex move one increment (I have snap to grid activated). If I press the arrow key four times quickly, I want the vertex to move four increments and etc. How can I achieve this?
Thank you.

To be honest I didn't even know that you could move an edge or vertex with the arrow key! I've certainly never heard of anyone modeling that way. You usually turn on Snap > Increment, hit G and move the mouse in the direction you want.

After a month I'm just going to assume that is just not possible for some reason.

I suspect that no-one has ever wanted that facility so has never asked for it. You could try suggesting it on Right-click Select but I doubt many people there are using Blender 3.3 now so it's unlikely you'll get any interest.


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How to animate cash being counted by a cash counter?
I need to make an animation of the cash flowing through the counter.
What would be the best way to do this?
I thought about starting with creating a bezier curve and adjusting it to make cash go through the counter to the counter wheels at the front and then I'd apply cloth physics to the cash and collision to the wheels so that money bends and is transported downwards where it's later pushed further by more cash.
Unfortunately, I've just started learning Blender and though I can successfully set up a curve and the cash follows it correctly, the physics part is more tricky. Cash constantly behaves unpredictably around the wheels. Usually resulting in going through the wheels rather than being nicely taken down.

usually the bills move so fast (unless you watch it in slow-mo) that you might be able to get away with faking it somehow. How realistic do you want this to be?

Yeah, I suppose you're right! This won't be watched in slow-mo, so definitely we can fake some things.

Suggestion.  See video tutorials on easy topics regarding items you do not understand. Please show your work regarding the bill movement. Please show 1 - 3 bills in your image.  Something you can manage.  Perhaps a small gif or sequence of images produced by Blender.   Showing just the counting machine is of quite limited value.

Suggestion.  Show in your work a bill moving along a path for a few frames.  [Follow path constraint].  Then show your bill being deform and bending. [simple deform modifier].  You may also choose to give the reader  a visual reference with a link to something similar to your goal.  For example ... here is a bill counter video that is similar to what I want .... link.

https://blender.stackexchange.com/questions/50396/how-can-i-animate-a-mesh-moving-in-a-spiral-fashion/50407#50407 is an example of some paper being deformed with [curve modifier]


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How to get started with blender
I am new to blender , I need to make a 2 min vid. Can anyone help me get started ?

Hello and welcome :). If you don't know where to start, check BlenderGuru's YT Channel. If you want more specific answers, ask more specific questions. Good luck.

This playlist is also very useful: https://www.youtube.com/watch?v=MF1qEhBSfq4&list=PLa1F2ddGya_-UvuAqHAksYnB0qL9yWDO6 - But phew, 2 minutes is A LOT of work, I hope you can make it :)


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Noise texture not working on two planes at same time
i have two separate planes, i have applied same noise texture in both the planes.
The problem is that it's only working on one of the plane.
Herein the image, you can see the upper ,although having same texture, is not showing the texture in lower plane.
What should i do now? Please help.

.blend could help.
But... have you tried applying the scale: Ctrl+A in object mode with the planes selected

You have two objects selected in Object Mode. The actual selected object is the one highlighted in a lighter orange. That is a) the last object selected and b) the Active object. You are seeing the Material attached to the active object.
As you can see in this screenshot, I have both objects selected as you do, and it appears that both have the same Material, but they do not.

If I invert the order in which I select the two objects, making the top plane the active object, you can see that the material is, in fact, different.

Select just the topmost plane and see what changes in the Material Editor.


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Why is object plane with texture appearing smaller in camera view, when cameras dimensions are smaller than the object?
I made my texture twice the size of the cameras resolution but it's appearing smaller. Will it be pixelated when I render out the scene?


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Hair look different between the viewport and the rendering, why?

The hair of my character is completely buggy when I render it (while normal in the viewport).
-it's a hair particle system rather simple
-I use the same display amount / render amount (100)
-The rendering picture is made with EEVEE and it does the same in Cycles.
It feels like the weight painting is replaced with random bugs.
Anyone has an idea about that?
thanks

Probably you have a subdivision surface modifier with a differenet amount on viewport and render. Adjust it to the same for render as viewport.

Oh thanks! It's exactly what was wrong


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parenting with Automatic weights but the mesh moves really weird
Im following this tutorial and i susessfully parented the armature to the mesh but the mesh moves really weird, is this an issue?

[![enter image description here][3]][3]

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


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Controlling Different Rotational Speed Of Two Interacting Objects
enter link description hereI have a problem modeling a Geneva Gear with two rotating parts, a cam which is driving a spur gear. The cam rotates continually, but the spur gear rotates by the action of the cam. I either need to slow down the rotation of the spur gear or make it interactive with the cam. BTW, I'm a noob.
Please download Blender file and run animation. I am not going to render the animation. It's fine the way it is.

The link is dead.

See https://blend-exchange.giantcowfilms.com/

You can use drivers to achieve this. Here is a demonstration: https://www.youtube.com/watch?v=ajMAvKRCTBg
Have fun!

Please do not post answers that rely solely on links.  See: https://blender.meta.stackexchange.com/a/2383/38953

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


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Move the origin point to the cursor in Edit Mode
I have a model where I would like to rotate an area of the object, in this case a mouth of a ordinary beast along a defined point, marked here with the 3D Cursor. And I am trying to move the selected areas Origin Point to the cursor, so in edit mode i press Ctrl+Shift+Alt+C and select "Origin to 3D Cursor. But then I get an error message that says, "Operation cannot be preformed in edit mode". Why??
I have Heard that you can snap the 3D Cursor to an object/vertex/edge/face but I have not found any reference of it...
It is a mirrored object btw.

My guess Ulf (and welcome to bse) is you are confusing an objects origin point with Pivot point  Set pivot point type to 3d cursor.

What I understood  about your issue, you want to open mouth and close it.
Please try following steps:

Select the base edges as shown in the image below, snap the 3D cursor to this edge, by hitting Shift + S and selecting Cursor to selected

Change the Pivot Point to 3D Cursor

Select the full mouth and rotate it as required.

You may also create a Shape key for easy rotate and animate
When you are done with it you may change back the Pivot point to Median point
Best of luck!


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Extruding from a plane creates a hollow shape
I am making a house in Blender with the help of architect sketches. I have done the wall shapes as 2d-planes, and when I extrude them to create the 3D-wall, it creates the wall but with one end hollow or open if you will. Is it suppose to do that, or am I missing something? Now I have to select the edges to close the gap with "Alt F", and I would love to avoid that procedure. Thank you in advance for your answers!
Best regards Ulf Nilsson

Recalculate normals.

Sorry for the late reply... Thak you for your help, it worked like a charm! :)


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Some models doesn´t show up when rendering
I have modelled a house for a technical information piece and I was trying to test a render just to see if everything was ok, but the walls of the house did not show in the render window. I was using the archipack addon to make walls and windows but something is amiss. I have materials selected and added to the walls, just a simple diffuse shader. This render is from Eevee, but I had the same result when I was rendering in Cycles.
Would love to hear from you experts what I can do to make this better.
Best regards
Ulf

Object Properties > Visibility >
Check all the render box is checked.
Also make sure all boxes in Ray visibility are checked.


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Using scenes to create an assembly instruction
We at my company are trying to make an assembly instruction of our product with the help of Blender. We want to do a IKEA style instruction with a series of assembly step (ca 10 steps), each in order, how to demount objects, move objects and then remount them in order. We then want to render each step and publish them. As I see it I have two options.

Use one Blend files for each step, based on the original model. (Not very efficient since there may be changes to the original model in the future)
Use the Scenes function in Blender, and make as many scenes as needed, with each assembly step in each Scene.

But what I cant figure out is how to keep the Blend file not becoming extremely big and heavy and to keep the transformations in each Scene separated. I tried the Linked copy of the model, in each scene, but then every transformation I make in one Scene gets copied to the others. For example, I move a plate. That plate gets moved in the other scenes as well.

I guess my question is: is there a way to use the Linked copy command and keep transformations in each scene separated?
Or is there a better way of working with these issues?

Another option would be to use animations to change object positions relative to each other starting from the assembled object.That way you are able keep everything in one file (or link from other files if there are several sub-assemblies) and have every step be just a bunch of keyframes


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Weird texture problem (Small vertex)
I've ran into a problem where when I apply a texture, the vertex on the Texture is very small and can't be scaled (It's really weird trying to describe this so here's some images).

GIF: https://i.imgur.com/Lp3eFXw.gifv
Is there anything I can do to make it look normal, it was normal yesterday and today it seems to be doing this on this texture and the gloves, it's really weird and confusing.
Thank you!

Can you share the blend file? It might be something with the active UVmap... hace you tried to UV unwraping again?

You probably welded the uv island- try to unwrap the model again.

How would I go about unwrapping it? When attempting to, it puts it into triangle (As does removing the UV Map) . Is there no way to reset it back to normal? I've managed to fix the eyes by importing it from the default unedited model and it worked normally, here's the files as the gloves are still broken with this problem: https://drive.google.com/open?id=1n3DJyJ_8mQA1ZCOXrNAZx4mNXRxBVdP6


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How to get smoke to pour out object holes?
I created an animation for Halloween and I want to add a wispy smoke effect to the eyes and mouth but the smoke stays inside the object.
Jack-o-lantern Animation
I am using a boolean modifier with an animated object to create the eyes & mouth, I first thought perhaps the smoke can't see the holes as the modifier wasn't applied but that didn't help. I have also watched numerous smoke tutorials but none address the issue I have.
Could you look at my blend file and let me know what I'm missing?

It looks like the resolution you are using for the smoke domain is too coarse. This makes the size of a smoke voxel possibly comparable or bigger than the apertures, preventing the smoke to "see" that they are there. By increasing it to 64 I've managed to see the smoke escape from both eyes.

To make sure that the smoke would come out within the time frame (I've done a test bake of 170 frames), I've also increased the time scaling factor, and I've added a starting normal velocity to the Flow object.
I'm not sure whether it counts, but I've also changed the obstacle type to "Animated" (doing this alone isn't enough, you'll still need to increase the resolution)

LOL thanks so much. Resolution was probably the only option I hadn't tried :)


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In Animation Nodes how can I have an integer value increase from 0 to 100 and back to 0? (0 -> 100 -> 0)
I am trying to create a smooth animation loop with a Euler Wiggle node and I have been unable to figure it out.
My goal is to provide an increasing integer value to the Evolution property and then when it hits a max, say 100, it would decrease to 0. This would allow me to create a longer animation with the Video Sequence Editor and save me having to render an excessive amount of frames.
I cannot use a simple duplicate sequence in reverse to emulate the effect as there is a background element that maintains the same direction of movement.

There are two ways to do this, the mathematical way, and the simple method of using an linear mirror interpolation which I will describe here:

In that case, it will start at zero, start increasing till it reach 100 at half the duration, and then start decreasing till it reach zero again at the full duration.

For future readers: Mirror Interpolation was missing from my menu and I found it using the search function.


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Why is my mesh highlighting the geometry?
Firstly, I apologize if this has been asked. I tried to search but I wasn’t even sure what terminology to use to describe what’s happening to my models. But I’ve modeled a drum clip for an assault rifle but some of the mesh is highlighting each individual polygon, here’s what I mean:

See how it kind of looks like a circular pattern and then again on the rounded sides you can see the individual geometry? What’s causing that and how can I remedy it? Thank you in advance for your help.
Here's what it looks like in edit mode:

this happens as a shading artifact when your mesh doesn't have enough geometry to be smoothed out nicely. another solution is to add a subdivision surface modifier.

@person132 That makes sense, I was kinda suspecting it might be something like that. This is good to know for my future models, thank you.

Try enabling Auto Smooth.
Select the object to be smoothed in the 3D View then access Object Data properties. Scroll down to/find the Normals options (click the ► arrow to expand) and click the checkbox marked Auto Smooth
Hope that helps.

That did it, thank you so much!


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All tools suddenly disappearing right after I add an object
Here you can see when I selected a rig, the rotate ball won't show up.

Any idea why did this happen?

You have the gizmos turned off in the viewport!

Try turning them back on!


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How to have sharp shadows in cycles with HDRI
Can you please tell me how to have sharp shadows in cycles with an hdri environnement texture, but without changing the lighting parameter of the hdri texture ?
For example in the picture below, I've got a simple plane with two meshes, the light comes from an hdri texture and I want the shadows to be sharper.
Thanks for your help !

You'd have to use a different HDRI if you want to use only an HDRI for lighting. The lighting you're getting is what has been captured by the HDRI. Choose one that has a strong light source in the picture, e.g. the sun or studio lights. If you want to keep the exact same HDRI, you can also add additional light source like a sun or area lamp.

You don't show an image of the HDRI you are using so it's hard to tell.  The quality of the shadows depends of the size of the light sources in the HDRI. Use one with direct sunlight, not overcast or where the sun is behind trees.

Thanks for tour replies. You're right, when I change the HDRI texture the shadows become sharper. But I thought there was a way to control the softness/sharpness of the shadows as we can do with the angle parameter of a sunlight.

When you use an HDRi as environment texture you are you are mapping an image in a giant sphere that surrounds the scene and emits light, so every pixel from the image contributes to the lighting in the scene.
As explained in the comments the sharpness of the shadows is directly related to the size of the bright elements on the image. An HDRi of a sunny blue sky will give you a sharp shadow, an image of an overcast or shady environment will give you softer shadows.
Other than controlling the intensity and placement of the image in the world, there are no built in tools to change the quality of the shadows.

related link: soften shadows projected by HDRi


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How do you sculpt the edges of a mirrored object?
I can't figure out how to sculpt smooth the edges of a mirrored object, it always gets edgy and i end up needing to manually move vertices down the z-axis which only makes matters worse.

Or when using the "inflate" sculpting tool i end up ripping apart the object.

Or "smoothing" tool creates sharp edges at mirror edges.

Any cool links with good techniques that can be employed to sculpt/work at those mirror edges?

Are you using the Mirror modifier? In that case you need to activate the Clipping option. But you'd better don't use this modifier and simply activate the Symmetrize option

@moonboots I have the same problem no matter if Clipping is enabled. Not ripping the mesh apart, that's taken care of by clipping, but smoothing edges towards the mirrored side to get rid of hard edges down the middle is almost impossible.

Oh ok I didn't know that but I'm not sure it's a good idea to use the Mirror modifier with sculpting

yes i used the mirror modifier. oh i thought sculptors used the mirror modifier. didn't know there was a symmetrize option. cool it works well with symmetrize! thank you @moonboots

You can symmetrize while sculpting (click on the X, Y or Z) and you can also click on the Symmetrize button whenever you want, in the symmetrize panel (down arrow on the right of XYZ)

@moonboots thanks for your help! sometimes though its weird when sculpt mode shows it smoothed out and when you go back to object mode there is a small edge. probably a bug but i can just go back in sculpt and smooth a bit again and check in object mode until its smooth again.

Not sure what you're talking about, maybe a bug

i meant that sometimes what you see in sculpt mode (some smoothed area) doesn't always look smoothed in object mode even with shade smooth on. but never mind it works fine :)

Don't use the Mirror modifier when sculpting, instead use the X, Y or Z symmetry option (you can shift click to choose a symmetrey on 2 or 3 axis at the same time). Also, whenever you want, you can click on the Symmetrize button at the bottom of the symmetry panel:


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How can I get exactly this gold lighting and look?
I'm trying to recreate this 2D cicular image design with the same lighting where the gold gets a whitish hue at the upper right fourth of the circle to make the whole image look like real gold with the nice dark red background.

I was able to recreate the design but I can't get the lighting right when camera view from top view. How do I achieve this same look where the gold has a nice whitish falloff into the upper right quarter? I want to make it look like a nice gold with the nice dark red color around as in the image or even better.

I would suggest using an HDRI for your lighting - studio style is best because it usually only has one or two light sources that you can "bring in to position" rather easily using a Mapping node. Blender's default Studio HDRI can be found at .../3.3/datafiles/studiolights/world/studio.exr
(NOTE - in the below image, I disabled all your lighting - all the lighting comes from the HDRI)

If you want to keep the HDRI lighting but keep the original background, use a setup like this, mixing the two backgrounds using the Is Camera Ray input of a Light Path node:

hey thank you for sharing!


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How to swap 2 vertices to fix a twisted face?
I've got some weird geometry where some faces got twisted and the only solution I know is to swap the vertices. Is there any easy way to swap vertices? Here they claim LoopTools > Flatten would do the trick but it does not work for me in Blender 3.3.

Simply select those two vertices, press S-1Enter to invert the vertices by scaling with -1 on all axes. No orientation needed. Of course this also works in Edge Select mode, then you just have to select one edge instead of two vertices.

Select the Normal orientation and rotate 180° on X?

hey thanks! that's a tricky one! I would need to add a custom orientation for every face I try to twist?

actually selecting the Normal option should work


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GN: Exporting Plant Growth Animation To Alembic Incorrect
I created this beautiful Plant to Tree Growth Animation at 30 fps using Geometry Nodes and just discovered that when i export the animation to Alembic (.abc), the animation goes kaput. I have no experience with alembic. You can see the leaves all scattered with huge sizes and the stem growing branches ahead of time without any leaves.

Any idea what is going on? I think alembic supports geometry nodes.

Basically, only what exists as a mesh is exported to another format (i.e. also the Alembic format).
Therefore, you would have to convert all instances into a mesh using Realize Instances and then export it.

However, this solution only works in Blender 3.2+!

oh my! you saved my life! my client would have killed me XD Thank you sooo much!!

@HarryMcKenzie Well, I'm glad that you will stay with us here on BSE for a while and that you will continue to honor us with your interesting questions and answers :D

Yes! I definitely will. I'm having a lot of fun here! pretty much learned a lot while learning 3D stuff and blender for the past 5 months! and it's nice to have some awesome experts here like yourself :)

btw the export works but in the materials view all the leaves are transparent, i can only see the branches and trunk but when i select the tree i can see the orange outline around as if the leaves are invisible. but its fine in solid mode.

hmmmm i tested rendering, the leaves are invisible.

@HarryMcKenzie When converting the instances into a mesh, the previously assigned UV mapping is lost. You would simply have to replace the node Texture Coordinate in the shader material "leaf" with the node UV Map and select the map "UVMap" there.

i tried plugging UVMap (with the leaf's UVMap object set) to Mapping node and tried all Type options, its still transparent. i can't get it to work :( can you send me the file???

@HarryMcKenzie https://blend-exchange.com/b/JoqKN1w5/

yeah that's what i did. leaves are still invisible in material mode. and don't render in eevee. but it does render in cycles. weird.

@HarryMcKenzie OK, this is really strange. The file I just sent you works the same for me in Eevee and Cycles. In both cases the material is displayed correctly (Blender 3.2). ...could you please share your file?

it is!! it is a bug! it actually works in blender 3.2! i just checked. in blender 3.1 it doesn't XD no wonder the client didn't complain. he said it works for him so i guess he is on blender 3.2 as well. so it's a bug in blender 3.1. do u also have 3.1 and can confirm this?

@HarryMcKenzie Oh, yes, you are right: I can confirm the behavior in Blender 3.1 ...probably one of the many bugs. But main thing it went well for you anyway ;-)

yes thank you very much! :)


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How can I make camera axis use "perspective mode by default?
When I use the keys "1, 3, 7" etc I get the frontal lateral view etc. And if I use "5" key the camera changes to perspective view. Is there a way to make the axis use perspective view by default instead orthographic?

You need to go to Edit > Preferences > Navigation > Auto : Perspective and turn it off.

Exactly what I needed, thank you!


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What is the best way to make a diagonal cut around a round object?
I have a curved plane and I want to make a diagonal cut that follows it, I use this method:

With the loop cut tool I divide the inferior portion of the plane.
I use ctrl+T to triangulate the faces of each vertical section, that
lets me generate a diagonal that follows the curve. The result looks
like the image bellow.
I delete the faces and I get the result I want

But, is there a better way to do it? Something like selecting 2 vertices and generating the diagonal between them, or something like the loop cut tool but in diagonal and around curves.
I ask because I may to need to repeat this process some times with my model and maybe there is a quicker way to do it.

If you want the cut through existing vertices, you coud start  by selecting 2 vertices on the diagonal you want followed, and use CtrlShiftNumpad +, Select Next Active, followed by J, Connect.

Hold down CtrlShiftNumpad +, to select continuously. J will connect all the vertices in their selection order.

That was exactly what I needed, thank you.

This is a low-effort answer, I was just going to post it as a comment, but decided it needed a screenshot to illustrate the point.
Use the Bisect Tool:


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What's the shortcut for hiding / showing the 3D cursor?
After reading the long list of shortcuts in blender I don't see it.

There isn't one.  You need to toggle a setting in Viewport Overlays.
But you can create one, or add a Quick Menu entry.
The 3D Cursor is an overlay  If you open the overlay menu in the 3D Viewport header you can find that it has a checkbox.

If you right click while you are hovering over it, a popup menu appears that allows you to set the shortcut:

or you can add it to your quick favorite menu if you don't want to tie a key sequence to it.  The short cut for bringing up the Quick Favorite popup menu is Q  Here's mine with only Show 3D Cursor as an entry

Note:  If you assign a shortcut key that is already assigned, Blender will quietly make the assignment, but the existing assignment will override and your shortcut won't work.  This is why I use the quick menu for things like this.


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How do I activate "snap to increment" in perspective and camera mode?
I thought snap to increment and absolute grid snap were only available in orthographic view, but somehow I managed to activate it in a viewport in perspective mode. How did I do that?"

I'm not sure what you mean, but all snapping options are available for (almost) all "modes" via the magnet icon at the top center of the viewport, and the corresponding dropdown menu to the right of it.

If it wasn't available in Perspective view, how would you see what you were doing when Snap to Grid was active? :^)

@JohnEason Since his assumption was snapping were not available in perspective view, there would be no need to see what you do... or do you think it's impossible to see it in orthographic view? I don't get what you want to say :D

@GordonBrinkmann Well he said that he'd "somehow managed to activate it in Perspective view" so I was just pointing out that  there wouldn't be much point in having a "Snap to Grid" option at all if it wasn't available in Perspective view. Probably a badly constructed sentence on my part! :^)

I use 3 view ports, one in orthographic in X and Z axis, one in orthographic in Y and Z axis and one in perspective view. That's how I used to use snap to grid in perspective mode.

I just realized my mistake.
I didn't realize that I had set a different grid unit in the viewport in perspective mode, so when I moved something there, it moved a lot. I had .0025m in orthographic and .025 in perspective. You have to use the same grid unit on all viewports for snap to grid to work correctly


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Render and Saved image look different
I was trying to render a circle that I would later add glare to in compositing. When I rendered the image with the compositing, it looked fin in blender, however when I saved the image it did not save the glare and it was just a white circle. Any ideas on why this is happening?
Blender     vs     Saved Image

Compositing

did you check compositing in post processing?

save as OpenEXR, it looks like PNG doesn't correctly save the glare effect over the alpha channel

ok I will try this

It still does not work

make sure that you've enabled transparency for the OpenEXR image when you open it with your software


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Top half of donut disappears when trying to hide the icing
Doing the donut tutorial. Duplicated the top half of the torus, made it into its own object, unchecked Edit Mode in the Solidify modifier, clicked Alt + Left Click to select the bottom row of vertices, clicked Invert to get the top half, then when clicking H, instead of just hiding the icing, it hides the whole top half. What am I doing wrong?

I think this is what you did. When you create the icing you are supposed to copy the original torus then separate it by clicking P. You did not copy the faces of the torus that you needed. You simply took part of the torus(donut) and separated it as the icing and therefore left your donut as half. You can only see the problem right now because you are trying to hide it. So you have to go back to pat when you started creating the icing mesh and make sure you copy the faces first and leave the donut whole.

Like I said, I duplicated the top half.

Also, Can you try drag all the meshes side by side to see if the icing and top half could be joined objects?


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grouping objects with modifiers so it behaves like one object
Grouping objects with modifiers so it behaves like one object.
Is it possible to make a such grouping?
I made shoes for a character that I want to animate.
The shoes are composed of several elements (sole, body, tongue, laces, etc) with various modifiers on each.
I already know that I will have to modify/adjust the model once I start to animate the feet, so I would like to keep it editable as much as possible.
Is there an easy way to make a such grouping that I didn't find yet?
Or, do I have to go through a trick, like create an empty in the middle of the shoe, parent all the elements to that and so on? but then, I am not sure if the weight painting will work.
what's the easiest solution?
thanks

Yes, parent to an empty or parent to the main part of the shoe... why wouldn't weight painting work?

so far, when I try that: every pieces of the shoes get separated when I move my skeleton

it's probably because you need to give some corrections in Weight Paint mode. Actually if your shoe is parented to a bone you don't even need to find a way to join the objects together, the fact that they are parented to the bone should work

ok, but then is there an easy way to not end up like this: (see attached pic, flying laces)
https://i.imgur.com/fEPKTqT.jpeg

the way is a correct weight painting   ;)   it's often necessary to rework after you've parent with automatic weight, with the brush in weight paint mode or with the vertex group list and the Assign or Remove button

OK I found a technique that work well so far: I use 'surface deform modifier' and bind the elements of the shoe's main body. It stick miraculously. It's even possible to use several surface deformers at the same time. Only the main body is attached to the skeleton / has weight paint. I suspect 'mesh deform' should be use in some other situations

yes mesh deform is great when you have cloths, it prevents any exagarate mesh twisting, in your case I thought you could fix it with weight paint only

@moonboots tell me, now that I render my animation, it's like the surface deform modifier had never existed. Preview window = the laces stick to the shoe, rendered video the laces stay in the air without moving an inch. Do you have an idea why? (I did activate the effect for rendering -camera icon- )

maybe share your file (only keep the important part)? https://blend-exchange.giantcowfilms.com/

@moonboots after further trials, it seems that when I put the effect on the top of the modifier stack it gets back to normal. Not sure why, not sure if my modeling will look exactly the same


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my fingers are bending weirdly, what did I do wrong?

I rigged my character with rigify.
I use the scale of the drawbars to make them fold, but they fold in strange directions. The pinky folds backwards, and it's like the first hinge of the fingers doesn't fold (only the 2 last phalanx)
Can I fix this? Or do I have to delete my bones and redo from scratch?
I guess it's about the orientation of the bones before I made the parenting but I'm not sure what rule I should follow...
Thanks for the help

OK, I will try to simplify my file and put it here soon

if it's just a problem of armature, just share the armature, not the mesh, put it here: https://blend-exchange.giantcowfilms.com/

I managed to reduce the file to 50 mb, it should be uploaded soon. Not sure where it will show up

oh no it should smaller than 30...

I managed now

wow you have not chosen the easiest rig, I'll try to understand

sorry, it's the only rig that I manage to get ;(

Problem
The bones on the pinky and the ring finger appear to be rolled slightly. This can be caused by excessively rotating or grabbing the bones in those fingers. Because some widgets rely on the local transformations of the bones (especially high-level widgets to control bone-synchronized movements like grabbing, walking, and bending), they can be easily affected by their roll.
To illustrate, I added a generic wolf metarig to an empty scene and generated its rig. The third bone in the tail will be used as an example of how bone rolling affects widgets.
Below is the tail of the metrig, with the third bone in the tail highlighted. No part of the rig was modified.

The generated rig still contains a natural bone structure in a wolf's tail after curling the tail by rotating the end widget.

Now, that third tail bone has been rolled by 190 degrees and highlighted in the next image. Nothing else was modified in the process.

After posing the generated rig, some of the tail widgets are out of tune with the rest of the body, causing the tail to become unnaturally distorted.

Solution
To fix this distortion in your model, I'd compare the roll values of the problematic bones in your metarig to those of the default human metarig. (While it is possible to directly edit the generated rig, I wouldn't suggest doing so because that rig is very complex and contains many hidden bones.) Copying the roll values from the default metarig to your modified metarig should correct the bending motion caused by the rig widget.
Once you are done editing the metarig, tab into object mode and press the "Generate Rig" button in the metarig's Armature settings. This will bring the changes from the metarig into the rig.

For reference, here's a list of each of the metarig's bones in the right ring finger and pinky with their corresponding default roll values:

hand.R: -127 degrees
palm.03.R: 148 degrees
f_ring.01.R: 115 degrees
f_ring.02.R: 109 degrees
f_ring.03.R: 95 degrees
palm.03.R: 144 degrees
f_pinky.01.R: 113 degrees
f_pinky.02.R: 109 degrees
f_pinky.03.R: 101 degrees

Oh! OK I see. Interesting...
But then, is there a way to fix those rotations once the parenting is done?
I tried to reorient the bones with the Roll slider in edit mode, but of course back in pose mode the hand was all distorted.
Anyway, when I see your example above, it makes me understand that the orientation of the bones has to be really precise. Is there a "right way" to do?

@Pyra_M You have the right idea. I just edited my answer to include the solution. Hope it helps!

Thanks, I just have done something similar but the fingers still bend in a strange way, I will try with your values.
So far I still have the problem that the base on the fingers/ the first phalanx is not bending. do you have an idea why?

It feels like it should be related to the driver, but every phalanx has basically the same driver and only the first phalanxes stay in place. I understand now that the drivers are referring to a sub-skeleton I am not sure why (the rig is generated from Rigify).

It looks like you might need to rotate those finger widgets to move the first phalanx of each finger, and that scaling is just for the outer phalanges. That applies to the human metarig as well. This makes sense because humans can control the base of the finger independently from the tips. I haven't used the human metarig for any of my 3D models before, so I might be wrong.

Ok, I understand better. Those finger widgets are very abstract, especially when the automatic parenting went wrong :)
I indeed followed the tutorial from the lollipop man
https://www.youtube.com/watch?v=UpAxY519IJU
in which he modifies some rotation properties on the finger bones.
That made my hand much better, I can almost make a proper closed hand now.
It also removed all my former weight painting corrections :(
Thanks for the help!


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Since 2.82 my computer completely crash on random occasions
I am using blender since 2.8 around October.
Since I installed 2.82 the software keep crashing together with my whole computer.
Not even a BSOD, the computer just reboot while I am modelling, or more recently while doing weight painting.
I deactivated most of the addons, and that have helped, but it is still crashing several times a day.
I even tried to get back to Blender 2.81 but the crash also occur with 2.81 now.
I believe all my drivers are up to date.
my configuration is:
windows 10 pro N 64bit
CPU intel core i7 4790 @ 3.6ghz
ram 16 gb DDR3 @ 798MHz
NVIDIA RTX 2070 gigabyte
I do not overclock anything.
I really have no idea what I could do to stop the crashing
Any one have an idea?

Could be a hardware issue. I would remove the graphics card and see if the problem persists. It could be a power issue or a graphics card issue (check the Windows Event Viewer after a crash).

NVIDIA. Could also be a problem with recent driver updates. I had those crashes frequently after driver updates until I switched to AMD.

I did change my graphic card about a month ago. But the crashes didn't start before february 17th after I installed 2.82. The event viewer mention error 41 kernel-power at every crash. I am not sure how to interpret this event. Is there a way to diagnostic that kind of error?
a power diagnostic tool?
a graphic card diagnostic tool? thanks for the help

Related https://blender.stackexchange.com/questions/167937/blender-2-82-crashes-often-what-should-i-do

@metaphor_set AMD is definitely not the solution here. There are various issues with their graphics cards and software - it's the same thing if not worse. In fact, I solved the exact same problem of computer crashing while using CAD software in my co-worker's work PC by removing an AMD card. The problem could be anywhere. It is also likely to be in the motherboard as it probably was in my case, but changing graphics card was the easier solution.

@MartynasŽiemys - this is very much opinion based. Also, the comment section is not the place to discuss the age-old "my  GPU is better than yours" question in lengthy case studies.

I am not discussing which is better, I am saying the brand is most likely not the cause (...despite Nvidia being better :D )

@batFINGER thanks for the link, yes and when the crash comes so randomly it's hard to make a bug rapport.

But, has anyone an idea how to test/diagnostic if it comes from the hardware?
I found a couple of software to test the graphic card. One called OCCT seems to test the power supply as well but I couldn't reproduce the crash.
The disturbing thing being that the crashes occurs in situations that don't demand any extra resource (i.e. moving a vertex)

For me this sounds like your graphic card uses more power than the power adaptor can deliver. And then the system becomes unstable. This would fit to your new graphics card and the kernel power error, even when it started with Blender 2.82 first. Have you checked if your power adaptor can deliver enough power to the system?
To calculate how strong a power adaptor needs to be, calculate the maximum watt values for all of your components in your pc together, and add 10% to 20% on top to have some reserve. There are some small users that are usually not worth a mentioning. A ssd usually uses around 2 watt. Same goes for ram. But a motherboard comsumes easily around 50 watt nowadays.

For the required PSU power supply you can also use online calculators to get an estimated value, such as the BeQuiet Power Supply Calculator.

OK thanks, I will try that :)

Just that i have asked, have you connected the graphics card correctly? Nowadays cards needs extra power from the power supply ...

yes I did put the extra power cable

Now I tried bequiet.com and it says:
"Your maximum wattage requirement 387"
my power supply has several figures about max power, but basically it says 'max power 500w'
but apparently  max 420w on some output, max 470w on some others, and 103W on a third type

One strange thing is that those reboots happen when I am modelling, with MatCap or Flat shading. Nothing really intensive

It's too hard to make diagnostics from here. Can't you put the old graphics card in and test if the problem still exists? That would be the easiest test. If the problem is still there then you have a problem elsewhere.

Yes, it would be the best test indeed. I will do that when I have the time.


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Vertices disappear after doing a "disolve edges"

I often end up with that problem. I must do something wrong, or I misunderstood the concept.
I don't understand why my vertex doesn't stay in place when I do a Disolve Edges in that configuration. Can anyone explain?
thanks

That's the way Dissolve Edges works by default, it also dissolve the vertices, but you can deactivate the Dissolve Vertices option in the Operator panel, I agree that it should be the default setting:

Thanks a lot! (late comment, though I had already answered)


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how to push back / repel clothes from a surface?

Hello!
I am trying to design clothes to a character that I made.
And I get stuck on that problem:
Is there an easy trick to repel the clothes from the body.
I modeled the clothes above my model but the holes keep happening.
I tried with shrink wrap Offset but it just makes the clothes to wide.
I tried to use the cloth simulator, but it doesn't solve the problem, and adds a lot of wrinkles.
thanks for the help,
Mathieu

Go into edit mode with a piece of clothing selected.
Enable proportional editing by pressing O. Turn on x-ray with AltZ in order to help you see the mesh stuck inside the model more easily.
Select a vertice that is inside the person, pull the vertice out of the character. Adjust the proportional size with your scroll wheel. This will determine how nearby vertices are affected. Repeat with other clothes.

cool it worked!


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where is the play button gone?

I must have pressed a keyboard shortcut by mistake, but it's gone for a few days and I can't find any menu to put it back.
What should I do?
Thanks

it is on the timeline. look at "animation" workspace.

The play animation button is not part of the Dope Sheet, it is in the Timeline. You've likely merged the Timeline area with the Dope Sheet by accident.
In order to add the timeline back:

Position your mouse courser between the Dope Sheet and the Properties. Right-click and select Horizontal Split.

Change the editor type to Timeline.

Oh thank you! I was getting crazy


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Pronounced color transition from light to shadow in cycles
I tried to achieve this effect in cycles for a long time. I tried to do it through subsurface scattering but after several attempts I gave up. today I saw this video and realized what needs to be done through the light path, but it is still difficult for me (
https://www.youtube.com/watch?v=UnxLy71xuPk&ab_channel=MarcoBucci

I don't believe what he is talking about in the video is true in terms of physics. There may be some truth in human preception. Light dispersion is a thing that can be visible and also we tend to see any color of light as white if it gets really intense, but there is no such a thing as hue falloff with intensity. We are used to see colder(blue) shadows and warmer (yellow) lighting outside because light that scatters in the atmosphere tends to be more blue, than the one that comes directly from the sun so shadows are colder in color and when shadows are soft, we see hue gradient. So this is basically, same as two different light sources - as if you had a huge softbox that emited weeker blue light, and a spot light that is more yellow.
I think this is the solution: have two light sources with different colors. One should be for ambient reaching pretty much everything, another smaller, casting shadows, so that the shadows of this one are illuminated by the first one. Like for example I set world lighting to blue, then used a spot light that is yellow here:


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I'm trying to make an image after using UV editor to unwrap it, but the previous image is coming up and the quality of the paint brush is pixelated
Ok so what I'm trying to do is draw the right arm right. So now I try to make a new image file for the second arm that way i can draw but even after I make one it goes to the other arm's file. Furthermore it does the same when i go to uv editor and select the new arm and project from view. I need some help pls if someone could explain. Or if you can walk me through step by step im live on twitch making it at https://twitch.tv/dashadowman_

Please clarify your specific problem or provide additional details to highlight exactly what you need. As it's currently written, it's hard to tell exactly what you're asking.

Please add a screenshot showing the UV workspace with the object in edit mode with all faces selected and a screenshot of your material nodegroups.  Also, is it possible that you have multiple objects showing in the scene?


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Striped obj/gltf
I am pretty new to blender.. I tried to make a logo from an SVG. I extruded the SVG and turned it into a mesh. But, I get this striped effect on the model when I export it... Why is this? I tried to perform a mesh clean up but hasn't helped

that looks like it might be z-fighting: two surfaces are in the same place and the render engine doesn't know which to use.  It might also be a lighting artifact.  Could you add your blend file to your question ((How to add a blend file) or at least include screen shots showing the wire frame of the text; the material nodes; and the outliner with all entries expanded?

It may also help to recalculate normals.


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Vertex groups missing when opening file
When I open my blend file,all of the vertex groups appear to be missing.
However when I tried to open it with blender's "recent files" option everything was fine.
What to do?

I also got the message "file written by newer blender binary,expect loss of data" now.

What version of Blender did you save the file in?  What version of Blender did you open the file in?

@Nathan,I opened it with 2.93 and saved it in 3.0 i think. It seems like the blend1 file works properly,but i want it to work as a blend file too.

This is expected: "Note that opening a file saved in 3.0 in an earlier version means the vertex groups will not be available.".

Can someone please write a plugin to fix this bug? Why would they break such important design features?

I had to use the Copy attributes addon to copy the vertex data: https://blender.stackexchange.com/a/16273/32655 for my case I also have to export the mesh from Blender 3.x as a .fbx to import to blender 2.x to preserver the vertex groups. Literally a extra 5 minutes of work now.


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How to change texture based on Height / Slope of object
I would like to merge two different textures using an Shadermix node and for the factor to be based on the vertical slope of the geometry.
Basically I want the flatter areas of the model to be one texture and the vertical areas another. I dont know how to do this? Any thoughts / ideas.

The direction that the geometry faces is its normal.  The up vector in the world is 0,0,1.  You can find the angle (in radians) between two unit-length vectors by taking the arccosine of the dot product of those two vectors.
Taking it all together, we can make something like this:

When the normal is facing in the +Z direction, there is no slope, and we're emitting green. As the slope increases, we mix with red emission.

You can use the Normal output of the Texture Coordinate, then put a (Converter) > Separate XYZ and use its Z output, now the color will depend on how the slot is close to Z:


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Realistic Friction Rigid Bodies
I am trying to do a "satisfying" video with physics and don't really know much about them. My problem is I can't figure out the right settings to make it look realistic.
Perhaps it is something to do with friction? It seems that if I change the numbers it doesn't really affect the results. Any help would be welcome.
Thanks!

WC

Blender File Download

I've increased the Mass (0.5) and Bouciness (1,2) of the balls, and also put a circle (Type > Passive, Shape > Mesh) on the front and back so that the balls don't jump out, and it seems to work fine:

Thank you! Did you come up with those numbers by just playing around with it?

I never would have thought to change the bounciness

yes just testing the parameters, also maybe switch the balls from sphere to mesh


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How to Constraints Objects to Curve Path?

Hello, I am somewhat new to blender. I am working on a short animation and want to have a sun/moon objects rotate through the sky. I thought it would be easy to somehow constrain the objects to a circle curve and then all I would need to do is animate the curve.
Is there a way to do this? I cant figure it out. Thanks for the help.

First problem is that you're using a mesh as the path.
What you want to use is the bezier circle under the Curves menu when you press ⇧ Shift +  A
Once that's done,

Click your moons and then ⇧ Shift click your curve
Press Ctrl + P and choose Follow Path.

That should do what you want

As it’s currently written, your answer is unclear. Please [edit] to add additional details that will help others understand how this addresses the question asked. You can find more information on how to write good answers in the help center.


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Way for my texture to emit light/glow on the Eevee engine
So, im working right now on a scene which ends with this red Ruby, im tryning to find a way for it to glow but keeping all its details, already went with the alpha map trick but doesnt get the finish version i want, its there a step im missing or there's another form??

In Eevee you have a very fast bloom function:

However that makes everything pixel bloom as long as it's brighter than the threshold. If you want to make single objects bloom you need to mask them some way and then use the mask for a glow effect in the compositor (post render). One way is to use object pass index.


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3d Print material 2.7x to 2.8 fix
This shader was a favourite of mine that I can't quite get to work right now, does anyone now to fix it without getting a pink object.


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Can "Exclude from View" be kept disabled during an append? Can it be done with Python?
This is a minor thing, but I was curious if this was possible.
I have generated a character rig that looks like this in the outliner. Notice the wgt folder is "disabled" and its contents are not visible (checkbox to the left of the eye is disabled)

However, when I append this character by just appending the "Character" collection, the wgt folder comes fully open. (checkbox enabled)

Now, pressing the checkbox is no issue post-append, but I was curious to know if there was a way to prevent this from the character .blend file so that it doesn't open when it's appended, and if it can be done with Python.
Thus far, I have this code that does a good job of excluding it on its own .blend file during the character rig generationg, but it doesn't prevent it from opening on append.
def recurLayerCollection(layerColl):
    found = None
    if (layerColl.name == "wgt"):
        return layerColl
    for layer in layerColl.children:
        found = recurLayerCollection(layer)
        if found:
            return found
layer_collection = bpy.context.view_layer.layer_collection
layerColl = recurLayerCollection(layer_collection)
bpy.context.view_layer.active_layer_collection = layerColl

layerColl.exclude = True

If it can't be done, no issue - but I'm curious to know if there's a way to do it solely for the sake of convenience.

You'd have to add your own custom logic when appending with a python script, because the exclude state is not stored on the collection but on the view layer (as illustrated by your code snippet). If you don't want to go that far you can try something else.
What you can do is disable the collection with the monitor icon instead.
First enable the monitor icon restriction toggle in the outliner settings.

Then disable the collection in the outliner :

You might want to also disable it from rendering otherwise its elements will show up in your renders.

Thanks for the follow up. Is there a way to make it so a python script (a text block) gets automatically ran when there's an append that includes that text block?


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Mesh created with Geometry Nodes is slightly shifted compared to mesh created with XYZ Math Surface
I was trying to complete my answer for this question. I'm creating an XYZ Math Surface via Add > Mesh > Math Function > XYZ Math Surface using the following parametric equations:
X: (g*f)/16*(3/2*((u**2 + v**2)*(1 + (u + v - 1)**2) - 2*(u**2*v**2 - 2*(u*v - u - v) - 1))/(u**2 + u*v + v**2 - u - v + 1)**2) + (sqrt(3)/6*(3*u + 3*v - 2)/sqrt(u**2 + v**2 + u*v - u - v + 1))*f/2
Y: (g*f)/16*(3/2*sqrt(3)*((u**2 - v**2)*(1 + (u + v - 1)**2))/(u**2 + u*v + v**2 - u - v + 1)**2) - (1/2*(u - v)/sqrt(u**2 + v**2 + u*v - u - v + 1))*f/2
Z: (g*f)/16*(3/2*sqrt(2)*((u**2 + v**2)*(2 - (u + v - 1)**2) - (u**2*v**2 - 2*(u*v - u - v) - 1))/(u**2 + u*v + v**2 - u - v + 1)**2 - sqrt(2)) - (sqrt(6)/3*(-1)/sqrt(u**2 + u*v + v**2 - u - v + 1) - 1)*f/2

parameters:
U min:  0.00
U max:  1.00
U step: 72
V min:  0.00
V max:  1.00
V step: 72
F:  2.00
G: 0

Which look like this if I'm not mistaken:
$$
x(u,v) = \frac{g \cdot f}{16} \cdot \frac{3}{2} \cdot \frac{(u^2 + v^2) \cdot (1 + (u + v - 1)^2) - 2 \cdot (u^2 \cdot v^2 - 2 \cdot (u \cdot v - u - v) - 1)}{(u^2 + u \cdot v + v^2 - u - v + 1)^2} + \frac{\sqrt{3}}{6} \cdot \frac{(3 \cdot u + 3 \cdot v - 2)}{\sqrt{u^2 + v^2 + u \cdot v - u - v + 1}} \cdot \frac{f}{2}
$$
$$
y(u,v) = \frac{g \cdot f}{16} \left( \frac{3}{2} \cdot \sqrt{3} \cdot \frac{(u^2 - v^2) \cdot (1 + (u + v - 1)^2)}{(u^2 + u \cdot v + v^2 - u - v + 1)^2} \right) - \frac{1}{2} \cdot \frac{(u - v)}{\sqrt{u^2 + v^2 + u \cdot v - u - v + 1}} \cdot \frac{f}{2}
$$
$$
z(u,v) = \frac{g \cdot f}{16} \left( \frac{3}{2} \sqrt{2} \cdot \frac{(u^2 + v^2) \cdot \left(2 - (u + v - 1)^2\right) - \left(u^2 v^2 - 2 \cdot (u v - u - v) - 1\right)}{(u^2 + u v + v^2 - u - v + 1)^2} - \sqrt{2} \right) - \left( \frac{\sqrt{6}}{3} \cdot \left( -\frac{1}{\sqrt{u^2 + u v + v^2 - u - v + 1}} - 1 \right) \right) \cdot \frac{f}{2}
$$
When I try to map the nodes in a custom node group named XYZ-Surface, I get a surface that is lower on the z-axis. They should be coinciding with each other:

All the other surfaces I made worked perfectly except this one. Since it is the Z that is shifted, the problem must probably lie in the Z equation. However, no matter how many times I recheck the node tree, I can't understand why it's not positioned correctly. I have checked this several times now to no avail forcing me to seek for extra eyes to look at this.

Here's what's inside the main Geometry Nodes modifier:

It must be something very simple for sure but I just can't spot the error I made. EDIT: Maybe not as simple as I thought since I discovered I have the same shifted problem for the bottom surface.

Jeeeez .. this is hard labour! Your existing answer is heroic :)

Is there really no way to just write a function in Geometry Nodes? We need to use a separate node for every single instance of every mathematical operation? That makes debugging something like this SO difficult...

@RobinBetts thank you! it was a pain but nice learning experience too with the organizational part in GN! For Lawton: Yes currently you have to manually map the nodes but there are a lot of reusable parts. I could have also grouped some custom nodes into another bigger reusable custom node. There is an addon which allows you to input expressions but I'm not sure how usable this is. It's also already outdated, as its latest version is 3.1 https://blendermarket.com/products/node-expressions?search_id=30672263

@HarryMcKenzie Node Expressions  crossed my mind. I didn't realize it had been updated to include GN. It's by Rich Sedman, of this parish, who, (I'm sure he won't mind me saying,) has been a primary example for me to try to emulate, here on BSE. :)

@RobinBetts hey guys good news look what I've found. https://github.com/WannesMalfait/Blender-Add-ons/releases I was able to immediately copy all the python equations and paste them to instantly create the node tree. wow should have known this earlier and saved so much time XD

There is an error in transposing the equation from XYZ Math Surface code to LaTeX. The last part of $z(u,v)$, computed in the frame "Z Equation Term 2", is written as:
$$
z(u,v) = (...) - \left( \frac{\sqrt{6}}{3} \cdot \left( -\frac{1}{\sqrt{u^2 + u v + v^2 - u - v + 1}} - 1 \right) \right) \cdot \frac{f}{2}
$$
whereas it should be (from the pseudo-code):
$$
z(u,v) = (...) - \left( \frac{\sqrt{6}}{3} \cdot \frac{-1}{\sqrt{u^2 + u v + v^2 - u - v + 1}} - 1 \right) \cdot \frac{f}{2}
$$
To debug, taking advantage that $g=0$, I specified $u=v=0$ for every grid point, yielding constant functions easier to track, after I noticed that the shift is almost the same at the four corners.

Side Note: I checked the rest and I could not find any mistake in the transposition. I did not checked the GN graph however... But after correction of the "Z Equation Term 2" frame, both surfaces are superimposed.

This is a video about Harry and Stef: https://www.youtube.com/watch?v=M61xXdVlP5o

oh my.. those parenthesis killed me lol. thank you so much! nice video btw! :D

A lesson in elegant debugging! Now I know there is such a thing :) @MarkusvonBroady :D great find! The copywriters earned their bucks, for once.


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How can I smooth out White Jagged Edges in Greenscreen Keying in Compositor?
I have a greenscreen video footage of a person, and I’m using the Keying node in the Compositor to remove the green background. However, I’m encountering an issue with white, jagged edges around the person. I’m looking for a way to smooth out these edges while maintaining a crisp outline and avoiding a hard cut-out effect, especially around the hair. This is the original video:

Here’s what I’ve tried so far, but I’m facing some challenges. The jagged white edges are leading to a rough output and forcing me to apply excessive feathering.

What techniques or additional nodes can I use in the Compositor to achieve a smoother edge with a more natural, feathery effect? Any suggestions to refine the outline and eliminate the jagged edges would be greatly appreciated.

I think your main problem is that you aren't actually greenscreening the video here, you're using input video that has already had some kind of matting applied. That green background is artificial and the white artefacts around his ear and neck are visible there. It's going to be a challenge for sure when much of the "bad matte job look" you're trying to avoid has already been baked in. Do you not have the actual raw footage with no matting applied?

@Jakemoyo Yes, I used vmake to remove the background, but it didn’t do a good job, leaving white jagged areas. Since MP4 doesn’t support transparency, it just added a green background.

Yeah, I really think thats where most of the artefacts are coming from. I don't think you can squeeze blood from a stone here if you don't have a good base of footage to work from.

@Jakemoyo thank you for the confirmation! well I guess I'll just have to stick with that from Vmake. It's unfortunate that there aren't any free video background removers online that can produce HD footage for free. Adobe and CapCut used to have one but now it's for premium use only :(

You do have the raw footage though? You could still try to see if you could key that manually in Blender, maybe add a little manual roto. I don't think the only solution has to be using an AI to remove the BG and you're left to tidy up whatever it spits out.

@Jakemoyo yeah I have the actual footage https://drive.google.com/drive/folders/1vjLxY5OzrzMX9UFu2GG_D42oQnu7b05l?usp=sharing but it is white background and when I try to key it, it will also remove the parts of the face XD

Yeah, then maybe you can key it most of the way with the Keying node, get a clean background removal (with some of the face removed), then create a basic garbage matte via manual roto that covers most of the subject roughly (any old shape that covers the artefacts will do, it doesn't have to be pixel perfect), then just subtract that from the matte coming from the keying node. Don't feel like you gotta get it all done with one single step. Use two or three "rough" passes layered on top of eachother to get a clean final result.

@Jakemoyo I solved it via bash scripting to remove the background from the original video.

I was able to come up with a better solution that removes the background of the frames in the original video via bash scripting using rembg. The result is a PNG sequence.

rembg is an open-source Python package that utilizes AI models to
remove backgrounds from images. It’s designed to help users quickly
and efficiently eliminate backgrounds from various types of images.

Install it on your command line (Ubuntu App if you're using Windows) using pip
pip install rembg

And install all its dependencies:
pip install click
pip install filetype
pip install asyncer
pip install gradio
pip install aiohttp
pip install watchdog

Create a shell script extract_frames.sh with the following script which extracts all frames from your video:
#!/bin/bash

usage() {
    echo "Usage: $0 --input <input_video> --output <output_folder>"
    exit 1
}

if [ "$#" -ne 4 ]; then
    usage
fi

while [[ "$#" -gt 0 ]]; do
    case $1 in
        --input) input_video="$2"; shift ;;
        --output) output_folder="$2"; shift ;;
        *) echo "Unknown parameter passed: $1"; usage ;;
    esac
    shift
done

if [[ ! -f "$input_video" ]]; then
    echo "Error: Input video file does not exist."
    exit 1
fi

mkdir -p "$output_folder"

ffmpeg -i "$input_video" -vf "fps=30" "$output_folder/%04d.png"

echo "Frames extracted to $output_folder"

And another shell script file remove_bg_frames.sh which will bulk remove the background for each image:
#!/bin/bash

usage() {
    echo "Usage: $0 --input <input_folder> --output <output_folder>"
    exit 1
}

if [ "$#" -ne 4 ]; then
    usage
fi

while [[ "$#" -gt 0 ]]; do
    case $1 in
        --input) input_folder="$2"; shift ;;
        --output) output_folder="$2"; shift ;;
        *) echo "Unknown parameter passed: $1"; usage ;;
    esac
    shift
done

if [[ ! -d "$input_folder" ]]; then
    echo "Error: Input folder does not exist."
    exit 1
fi

mkdir -p "$output_folder"

for img in "$input_folder"/*.png; do
    if [[ ! -f "$img" ]]; then
        echo "No PNG files found in the input folder."
        exit 1
    fi
    filename=$(basename "$img")
    rembg i "$img" "$output_folder/$filename"
    echo "Processed: $filename"
done

echo "Background removal completed. Check the output in $output_folder."


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How to join two separate mirrored objects
I’ve sculpted two heads seperate withe the Mirror modifier. Also the shrink wrap is Al over the two objects. If I join them, the points don’t clip and I can’t merge the points, because the mirror modifier isn’t on the same side. Can someone help me ?

Difficult to imagine what you're talking about without some images! https://meta.stackexchange.com/questions/75491/how-to-upload-an-image-to-a-post

Hello, Sarah, and welcome. It is very hard to understand what you might mean in this question. As John has commented, a  descriptive image of your situation may help   us get there.


text:
How can i create a new edge loop / vertices where i've joined two separate objects? Boolean gives me strange results

Hello, I am very new to blender.
I would like to join the top part of my vase (the long bit) with the base, and bevel out the join so its not so sharp. (same with the handles.)
I've tried to use the Boolean modifier but it looks really strange and i'm not sure why. I know my shapes are wonky on purpose.
Ideally i'd like a new edge loop where they intersect so i can bevel it. What else can i try?

Joined objects without Boolean

Objects with Boolean (Union) and it's gone weird.
Thanks for any help.

You need to correct the topology, or cut a in your bottom object, make a circle from this hole (right click > LoopTools > Circle) and extrude up your vertical tube?

@moonboots Yes I'll try and combine this method with Harry McKenzies method and see what happens, thank for your replies

@HarryMcKenzie Thank you for your answer, I'm currently trying to follow it to attach my jug handles to the long bit, after cutting a hole and extruding the long bit. I've selected my handle mesh and in edit mode, clicked "Intersect (Knife)" but it's telling me No Intersections found. Do i need to Join the jug object with the handle object?

yes first join them so they are part of same mesh. select the handle then shift select jar then press ctrl+j


text:
How can I make the Rotation property easier to edit on the Graph Editor?
First time trying to animate in Blender.
Im animating something spinning 720 degrees and my Graph Editor looks like this zoomed all the way out to accomodate the keyframes for the Z Rotation.

It's really hard to see and i can't accurately click the bezier handles even when zoomed in. All my other keyframes are small at the bottom

Here it is zoomed in to the other keyframes but now I can't see my Z rotation ones. I'm used to the After Effects graph editor where it proportionally scales the graph editor depending on the values for that property. How can i do something similar for Blender? Sorry I don't know how to word this question to google it!
Thanks.

i don't think (AFAIK) that it is possible to have different scales at the same time in one graph. You can zoom to one of it  - of course - but the downside is then, that you might not the the other graphs at the same time. Maybe a solution for you might be to open two graph editors at the same time with different graphs zoomed.

You can drag mouse on the axis indicator on the right of the dope sheet to scale the view across only the Y axis. It's a little clumsy but it should allow you to see your handles better.

apologies for my ugly arrows.

Hi @ruckus I'm the OP (Olivia) but i forgot the login to my account, and this one is too new to upvote or reply to your answer but that's helped for me, sorry for the slow reply!

Hey no problem im here to help. this might help with your account problem.


text:
Seamless z rotation loop animation still has jitter when rendered
As a test, I am using the default cube and an empty which the cube is parented to.
I have 360 frames with playback set to 60 frames a second. I rotate the empty in the z axis between 0 and 360 degrees. Key frame 1 is set to 0 degrees, key frame 360 is set to 360 degrees. Total animation lasts 6 seconds.
I have also applied a linear transition between the key frames for a constant speed, as suggested by others here.
Playing the animation in Blender looks lovely. Once exported and played in any video playback application, e.g. VLC, Windows Media Player etc, there is a slight jittering/jump when the animation loops.
I've tried setting frame 0 (outside of the rendered range, as suggested by others).
I've also tried setting keyframe 361 (outside of the rendered range, as suggested by others).
I've also tried 0 - 359 degrees, but all attempts have no impact on making the loop appear seamless.
I've also tried adding the rendered animation (mp4) to a web page video container set to loop, but the issue is still there.
I'd like to get a better understanding of what I might be doing wrong:

Am I setting the keyframes for the rotation incorrectly?
Is it due to the limitations of the video playback application / video html container, I'm hoping not

Thanks in advance :-)

For 1. well it seems you tried different variations, I guess one of them should have been correct. See my answer how it usually works. On question 2. I don't think the container is not able to loop seamlessly, but you just said "mp4", there are a lot more settings for encoding quality etc. so maybe it has something to do with it.

In order to make a smooth looping rotation from 0° to 360° degrees you have to consider that 360° = 0°, so if your rotation is 0° on the first frame and 360° on the last frame, the initial position of your object is on two frames, while all other angles are just kept for one frame which can make the loop switche from end back to start look strange.
Usually it should work like that: if your animation goes from frane 1 to frame 360, you would set the rotation to 0° on frame 1 and 360° on frame 361. This way the animation ends one frame before the rotation switches goes to 360° = 0° and thus make it look smooth.
This way the angle of rotation is (frame - 1)° which ends at 359° on frame 360, the next frame would be 360° but it goes back to start where you have 0° again.
In general this is how it works - and it doesn't matter if the frames are as many as one per degree - even if you want a very quick rotation within 50 frames, you have to set the 360° not on the last frame 50, but the last frame + 1 = 51.
If however this doesn't make a seamless animation in any of your video players, then there is either something not as described in my example or the players are somehow not capable of playing the video file seamless. But this is something we cannot solve here.

Thanks Gordon. I think that the video players simply can't loop precisely as Blender does.
I will have a go at trying other methods such as rendering out PNG's and then importing them into Adobe AE or something and then export that as another movie file to see if that works. If you ever happen to try the steps I originally took just to confirm I am not going insane, that would be fabulous! Thanks again and good luck out there!

Well, the first step you described is setting frame 360 to 360°, this will definitely not loop seamless, no need to try that. The other things (setting frame 0 to 0° or frame 361 to 360°, or just going from 0° to 359°) all result in my answer more or less. An easy way for you to see if it is the players would be to render an image sequence and edit it together two or three times so that you have 12 or 18 seconds. If it loops seamless within the movie but not at the end, then definitely the playback is the problem, not the loop itself.

Thanks again Gordon for your views and guidance. I will definately try that.


text:
Animating an Object to Appear / Disappear
I need to animate an object's visibility from opaque to fully transparent in a scene, and this object has many materials that are shared by other objects in the scene.  As I understand it, my only option is to create a single user copy of each of the materials for the object I need to 'disappear', then add a transparency shader to each of these materials and then keyframe that shader's strength (for each material) in order to achieve this.  This seems very complex for such a simple objective.  Anyone know of a better way?

I personally think the best way is doing that in comp...

Thank you - I should have mentioned, I am using Cycles to render.

If you don't want to fade in/out, but simply make objects appaear/disappear you can keyframe object visibility ('visibility' section in 'object properties' tab).

related https://blender.stackexchange.com/questions/150660/keyframe-object-in-and-then-out-of-scene/150668#150668


text:
How to remove HDRI background in lookdev mode?
How to remove HDRI background in lookdev mode? I'm using Blender 2.9.

Very easy. Go to shading tab and set the world opcity to 0.

Aaaaah. thank you very much! I figured it was something simple and obvious like that.  Much appreciated!


text:
How do you turn off the 'Auto X-Ray Mode'?
Every time I enter edit mode, X-Ray is automatically turned on.  I know how to toggle it on and off, but I want the default entry into edit mode to have X-Ray off.  Any suggestions?

maybe you have the same shortcut for edit mode and xray toggle?

interesting idea. I think you're onto something with that, although its not quite the problem.  I'm using Hard-Ops addon and one of its pie menus is used to quickly enter object / edit mode. When I use that, it auto turns on xray, but when I enter with normal Blender it doesnt. Your suggestion revealed that, so maybe its an option in Hard Ops I somehow toggled on.  Cant seem to find it still.  Thanks for your input!

Unfortunately I don’t know hardops….

No worries - I appreciate your suggestion. Thank you.

This can be fixed by turning off the Toggle X-Ray ON option for Modes Pie in the MACHIN3tools add-on preferences.


text:
Why is this boolean slowing my simple scene down so badly? I'm using it as an 'Intersection' to see on this portion of an array passing through
Boolean shown in wireframe, allowing smaller rectangles (with array modifier active) to be seen as they pass through along the Y axis.  FPS is set to 30 but playback crawls at around 7fps. The boolean is definitely the culprit - when I deactivate it, playback is fine.  How can this simple modifier slow things down this much? What am I missing?

can you please explain a bit more, what you want to achieve? Maybe a boolean modifier isn't necessary...

Hi Chris, I am trying to make an animation where only the section within the boolean will reveal the rectangles passing through.  I'm trying to build a stylized smart phone, showing screens passing by as they are scrolled through. I've seen this done online with no issue, so I'm not sure why this approach isn't working with my setup.

a boolean operation is not always that easy. It depends on the geometry which is used. And looks like in your case it must be calculated each frame. I asked because sometimes you can "hide" things with e.g. a plane or something else without using boolean modifiers. This would be much quicker.

Interesting. Can you briefly describe how you would hide something moving with a plane?

I am not sure what you want to cut out, but here is what i mean: [1]: setup: https://i.sstatic.net/txk8B.png -> if the camera is above it "sees" this: [1]: https://i.sstatic.net/Wy5MP.png. And you could get the same result with a boolean modifier. It depends what you want to cut out. So IF you just want to cut-out something like a phone frame and render only the phone frame, this could be an alternative.

So what exactly is creating that gap in the blue plane? Is it another, unseen object?

Hello, try using the "Fast" solver, the "Exact" one is notoriously slow.

Ah yes! that totally worked - thank you so much, Gorgious!


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Weight painting doesn't work properly if bones are moved
I am following the RPG graphics tutorial  to learn how to rig and animate a body(Although I am following on blender 2.8). Everything has been going fine up until the weight painting. Now, the weight painting works fine if I don't modify the pose in any way. But if I do pose the model and try to paint, blender acts as if I didn't modify the pose at all. I can have both arms up in the air, but I will have to paint as if the model is in the resting position. Does anyone know what can be causing this?
The tutorial
Blend File

The good news is your .blend file is fine. I had no trouble weight painting after changing the pose.
If, by any chance you didn't upload your latest version of your project, please make sure Pose Position is enabled, the Armature Modifier is turned on in the Modifier Tab and remove all keyframes or set keyframes for the current pose on the current frame.
I hope this was helpful to you.
On a side note: you should switch the Shading from Look Dev to Solid in Weight Paint Mode, otherwise the textures will make it harder to see the colors from your Weight Paint.

This is really strange because you are the second person to say it works fine. It is the latest version of my blend that I sent and for some reason it's just not working for me.


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Blender problem UV texture after applied subdivision surface

Can someone help me to fix this UV texture please ? Thank you. The texture should be like first image after I applied smooth in Subdivision Surface in Modifier. Thank you for any helps !

It looks like part of your mesh isn't unwrapped and the subdivision modifier streches that part out.
But maybe the newly created geometry is dragged around your entire UV Map similar to this:
In that case try separating part of your leaf using P and then joining both objects again by selecting both in Object Mode and pressing CTRL + J

It worked for my leaf Thank you !


text:
How to add trailing light effect to finger tips?
(as advised I deleted my previous question)
I would like to add a light streak effect to the finger tips of this animated dancer.

I am using a particle emitter that is assigned to a vertex group (finger tips) but I am unable to get them to give me a streak effect.
So far I can only get this:

and I would like something closer to this: (I'd be delighted with something far more simple)

I've seen tutorials on line but they were in Blender Render and not Cycles. Is there a way to get the streak effect with a particle emitter in cycles?

Related https://blender.stackexchange.com/questions/24251/how-to-create-motion-trail-in-cycles

You can achieve this by using particles to trace out the path of the motion and converting each particle system into a Curve object. The curves can then be used to draw the trails and animated using keyframes to match the motion.
Start by adding particle systems to the mesh. It's important to have a separate particle system for each 'trail'. The order the particles are emitted will control the order of the points in that trail.
There are two ways of achieving this.

Create a mesh with a single vertex and add a particle system. This can then be duplicated, positioned, and parented to the moving mesh so that it follows the motion. You can create as many of these 'trace' objects as are required.
Emit the particles directly from the mesh being traced. It's important that each particle system emits from a single vertex - so use Vertex Groups to limit the emission for each particle system, adding a particle system for each.

Ensure the particle systems are set to emit the particles with no initial velocity and that the relevant Field Weights are set to zero so they are not affected by any forces present. This should result in the particles 'hanging' at the point they are emitted.

Once you have the emitted particles, open a Text Editor window and paste the following python code :
import bpy

def particles_to_path(objName, tracks=1, particleSystem=0, curveResolution=0, bevelDepth=0.1):

    object = bpy.context.scene.objects[objName]

    particles = object.particle_systems[particleSystem].particles

    trackNo = 0
    trackPoint = 0
    curves = []
    splines = []

    for p in particles:
        if trackPoint == 0:
            # Create new track
            curve = bpy.data.curves.new('particlePath', type='CURVE')
            curve.dimensions = '3D'
            curve.resolution_u = curveResolution
            curve.bevel_depth = bevelDepth
            spline = curve.splines.new('NURBS')
            curves.append(curve)
            splines.append(spline)

            #set first point
            print(spline.points[0])
            print(spline.points[0].co)
            spline.points[0].co = (p.location[0], p.location[1], p.location[2],1)
        else:
            # Add point
            splines[trackNo].points.add()
            splines[trackNo].points[trackPoint].co = (p.location[0], p.location[1], p.location[2],1)

        trackNo += 1

        if trackNo >= tracks:
            trackNo = 0
            trackPoint += 1

    # deselect all
    for curve in curves:
        curveObject = bpy.data.objects.new('particlePath', curve)
        bpy.context.scene.objects.link(curveObject)
        #...select it?

particles_to_path('Trace',particleSystem=0, curveResolution=8)

The code defines a function (particles_to_path) which will use the particles emitted by a particle system on an object to create a Curve object. Note the last line in the script which invokes the function, specifying the object 'Trace'. This will use the first particle system on the 'Trace' object and will create a Curve. To invoke the function on multiple particle systems, simply duplicate the last line and change each as appropriate.
For example, for multiple objects named 'Trace', 'Trace.001', 'Trace.002', 'Trace.003', etc. use the following lines :
particles_to_path('Trace',particleSystem=0, curveResolution=8)
particles_to_path('Trace.001',particleSystem=0, curveResolution=8)
particles_to_path('Trace.002',particleSystem=0, curveResolution=8)
particles_to_path('Trace.003',particleSystem=0, curveResolution=8)

If you have multiple particle systems on the same object, each emitting from a single vertex then you can use the 'particleSystem' parameter to indicate which particle system to use (0 = the first one, 1 = the second one, 2 = the third one, etc.) :
particles_to_path('myMesh',particleSystem=0, curveResolution=8)
particles_to_path('myMesh',particleSystem=1, curveResolution=8)
particles_to_path('myMesh',particleSystem=2, curveResolution=8)
particles_to_path('myMesh',particleSystem=3, curveResolution=8)
particles_to_path('myMesh',particleSystem=4, curveResolution=8)

Once you have generated the curves, simply adjust the curve properties to generate the required trails. For example, set Resolution and Fill in the Shape settings to generate a curved shape...

...and use the Geometry Bevel settings to adjust the 'trail' - setting Start and End to position it along the curve :

Note that the Taper Object can be used to specify an additional curve object which defines the shape of the bevel along the curve (with Map Taper enabled to taper the bevel along the Start-End interval rather than the whole curve).

Carefully keyframing the Start and End will allow the trail to be animating. Ensure to set the Interpolation of the animation curves to Linear so it matches the motion of the particle emitting mesh.
For the material, you can use a combination of Emission and Scatter on the Volume. This will allow the trails to be partially opaque while still emitting light. Mixing in a Transparent shader based on the light path allows them to be hidden from all but the camera (so they don't reflect off of the surfaces). Including variation based on the Random object info provides automatic variation for each trail (you could assign individual materials manually in you prefer more control).

This can produce the following result :

Blend file :
Applying this to the example 'dancer' mesh can produce the following effect :

EDIT: I have since packaged the above script as an add-on as part of this answer, available from here. This makes it much simpler to run and avoids the need to create and edit a custom script.

WOW! Thank you so much. I learnt a lot from your answer! :)

Can we do the same thing with Animation Nodes?

@unfa From what I’ve see of Animation Nodes for other questions, I imagine so. However, I’ve never got very far with AN - I struggled to get it to install on my system due to python and library issues - so I don’t really have the experience to comment on that. Perhaps start a new question linking to this one and asking if anyone can do similar with AN.

How exactly do you set up the taper path object?

@Legoman The taper object is essentially just a path that varies alog its length to define how your curve bevel tapers - the further from its own local Y axis, the thicker the bevel. See https://blender.stackexchange.com/a/8691/29586 - hope this makes sense.

Rather than the PS, consider using the pose bone's  motion paths directly, to  visualize  and  drive your generated trail.  API doc

@batFINGER That could work if you had a bone but what if the point of interest is a vertex or a face - or if the animation is without armature (such as rigid body). Using a particle trail does require more set up and steps but gives the added flexibility.

Also works for objects. Parent an empty to a vertex, copy location constraint  to vert group  for examples.

Hi I took the liberty of updating Rich Sedman's script to work in 2.8
import bpy

def particles_to_path(objName, tracks=1, particleSystem=0, curveResolution=0, bevelDepth=0.1):

degp = bpy.context.evaluated_depsgraph_get()
object = bpy.context.scene.objects[objName]
particle_systems = object.evaluated_get(degp).particle_systems

particles = particle_systems[particleSystem].particles
trackNo = 0
trackPoint = 0
curves = []
splines = []

for p in particles:
    if trackPoint == 0:
        # Create new track
        curve = bpy.data.curves.new('particlePath', type='CURVE')
        curve.dimensions = '3D'
        curve.resolution_u = curveResolution
        curve.bevel_depth = bevelDepth
        spline = curve.splines.new('NURBS')
        curves.append(curve)
        splines.append(spline)

        #set first point
        print(spline.points[0])
        print(spline.points[0].co)
        spline.points[0].co = (p.location[0], p.location[1], p.location[2],1)

    else:
        # Add point
        splines[trackNo].points.add(1)
        splines[trackNo].points[trackPoint].co = (p.location[0], p.location[1], p.location[2],1)

    trackNo += 1

    if trackNo >= tracks:
        trackNo = 0
        trackPoint += 1

# deselect all

for curve in curves:
    curveObject = bpy.data.objects.new('particlePath', curve)
    bpy.context.scene.collection.objects.link(curveObject)
    #...select it?

particles_to_path('objectName',particleSystem=0, curveResolution=8)

Thanks Bent, always nice to see new approaches

Just noticed this answer. Thanks for the update to the script, @Bent. I have since updated the add-on available at https://github.com/baldingwizard/Blender-Addons/wiki/Particles-To-Path to work at 2.8+


text:
How can I switch connected Falloff nodes on a keyframe?
I have an an animation setup that uses a Falloff node to animate my scene into view and at a set frame I want another Falloff node to handle the fade out of the object but right now I have to manually connect the node at my desired frame.
FADEIN:
The Offset Matrix node is set to End and the object fades into view.

FADEOUT
The Offset Matrix node is set to Start because I want the object to exist and then Falloff by reducing its scale. I can keyframe the Offset Matrix node's options but I have to manually connect the FADEOUT Falloff node and continue from that frame. I'm sure there is a better way to do this but I've been unable to solve it.
Is it possible to switch connected Falloff nodes on a keyframe?

I continued my SOW browse and came across a post that mentioned the Switch node. I combined this with a Compare node using the Time Info node and I have exactly what I needed.
Credit to 3pointedit for asking this question How can I drive the Switch nodes True/False value?


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Is it possible to use compositing to remove patterns in rendered images?
I rendered hundreds of frames and when I reviewed the results I found that the camera can see 'through' my stack of objects to the background and a grid pattern is visible. I could render again with an object to block the light path but I'm curious if compositing provides another approach.
Is it possible to use compositing to remove such patterns in rendered images?

You could use the Mist pass with a color ramp and color invert to strengthen it, or you could do like the included image, enable an Object Index pass so you could then get a strong mask and invert it to affect the areas outside of the object. In this way, even if you need to render frames again, you can lower your settings all the way so that the result is as small as possible and just use the pass to affect the frames you already have.


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Volume Absorption is only applied to the "top" of a mesh
I am following the BlenderGuru tutorial of making a cup of coffee, but when I make the coffee liquid using volume absorption, the coffee only appears to absorb light from the top. When I adjust the view to the sideview, it still looks transparent.
Anyone know what I do wrong? Please see the image with nodes attached.

I checked out the video you mentioned. I can't listen, because I can't find my headphones, but around the 11:20 mark he discusses re-calculating normals. Have you done that step? I think recalculating-outside should fix your problem.

Hi Chris, thx for the reply. I have selected all the vertices, and done the recalculation of normals. it looks all blue in the "face orientation" view. But still, the volume absorption only applied to the top!

I am new to Blender, so I can't say I solve this problem (I am quite sure if the coffee cup is animated, the coffee liquid won't looks right)
, but I do discover what causes this problem.
When the scene setting is like the follow (the camera looking at the perpendicular to the light source), the side of the coffee mesh looks transparents.

I changed the scene setting like the below (the camera facing the light source)

Now the volume absorption works! the side of the coffee is now brown instead of transparent.
I am guessing this is due to how volume absorption works. If there is no light passing through the mesh to your camera (i.e. camera perpendicular to the light source), the volume absorption calculate that there is no light absorbed at all, meaning transparent. (but in real world, it should appeared darker, or something else, but not transparent).
Hope this makes sense, if you guys happens to know how to make it more realistic, please tell me. thanks!


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Laser bolt glare problem in blender 2.9
So I'm trying to build a laser bolt like in Star Wars, and I added a cylinder with an emission texture. The problem is, in Star Wars, the laser bolts have glare, so I added a glare node in the compositing tab. I rendered the image with the camera, and there was no difference.

Please add the .blend by using this uploader: https://blend-exchange.giantcowfilms.com/b/LgRwe6jm/, without knowledge of the rest of your setup it is nearly impossible to determine the actual cause (without lots of external knowledge), it basically becomes guesswork

Does this answer your question? Glow with depth in Blender? read also: control halos in compositor based on emission levels

try changing stroke dropdown to fog from glare node of simply mix original image with a blured one

You need to use a higher value then 0 in you Mix Slider from the Glare, or the Glare wont mix in your Picture. This will make you Picture a little bit darker but the glare will be visible, you can counter the darkness with the Threshold Value.


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is there a way to change the saturation value by using a light?
My scene's background is too bright and too saturated compared to my foreground.
To lower the brightness, I used a lamp with a negative value, which made my background darker. But is there a similar solution to lower the saturation or the contrast?
How do you manage globally the colors/saturation/etc. of big parts of a scene?
Thanks!

i would search for the reason of your bright background, and reduce that. But since we have nearly no information about your setup - we can just guess. Maybe turn down the strength of your background node in your world shader? If you wanna have a precise answer, pls upload your blend file. thank you.

@Chris sorry for being so vague, but my question is very generic. Is there a way to reduce locally the saturation of a set without changing the shader one by one, in the same way that you can reduce the light with a lamp with a negative value?

my problem is also to have the saturation reduced uniformly

Hi Pyra, i also just know the trick with the negative value of a lamp, sorry.

Please flesh this question out a bit. Is your background an HDR ( World) .. or lit components of your scene?

@RobinBetts it is lit components


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in GreasePencil, how to add inbetween frames like the F5-key in Adobe Animate?
Is there a way to easily add inbetween frames, without using the mouse and moving everything by hand?
Like the F5 key in Adobe Animate?
Thanks!

Could you please elaborate what F5 does for non adobe users?

Are you talking about Interpolate Sequence?

@brockmann basically F5 adds a space in front of your keyframe. So if you want a keyframe to last 2 frames or more, you just press F5.
It is very covenant to adjust your timing while drawing, without having to use the mouse and going in the timeline.

@ChristopherBennett no no I don't talk about the interpolation tweens. I just want to quickly make the dark bar that is between the keyframes longer. You know what I mean?

AFAIK you can't, but it's totally possible to do this with python scripting

Too bad, I don't know anything about Python. Thanks @Tomreggae for letting me know

I wrote an addon that makes this a bit faster: https://github.com/bergamote/greaspencil_nudge_frames

@wilks EXACTLY WHAT I NEEDED! Thankx