text:
How to get bloom effect when there is a gradient background?
So I want this kind of effect

trying to emulate the dark room effect but was thinking of adding some sort of gradient to the background to make it look interesting
but the moment i do that i get this

I lose the effect of the night time style was wondering if there is a good way to do this in in evee. My plan was to make something that emulates a lit screen in a dark room

It's hard to tell from your images, but it looks like it's possible that the World Lighting from your scene is too bright for the bloom and kind of "overrides" it. If you want to keep the look of the background without having it influence the lighting in a scene, you can mix your (gradient) background with a plain (dark) background with a Mix Shader, using the Is Camera Ray output of a Light Path node as a mix factor. This will separate the environment "look" from it's lighting and reflections.

hey so ya i have the is light ray on the shader https://www.youtube.com/watch?v=hGBd6bgEAxY used this guys tutorial to create the background, I can't seem to find the the world lighting thing u said about, i think the effect u have is exactly what im looking for, do u mean the strenght level in the background node form world? I'm still new to blender so am confused if u could post ur blend file that would be super helpfup!

just did the same procedure as urs from the pic and still am not getting the glowy effect that i have shown in my first pic

Not sure what's going on then. Maybe something to do with your bloom settings? It's hard to tell without knowing more about your file. Sorry I can't post my .blend file because I just made it as a quick mockup and never bothered saving it.

ah gotchu is there a way to chat on stack exchange i think there was a way but its been long time so i forgot i can share my setting or even the blend file

You can upload your file here - https://blend-exchange.com/ Just copy the link they give you, edit your own question (on this page), and paste in the link. Unfortunately I have to leave my computer right now, but I'll take a look later when I get back. Hopefully someone else will have a better answer for you in the meantime.

ok thank you very much

Ok I think I see the problem here. This doesn't have to do with world lighting as much as it does with your objects materials. If you want something to "glow" (with a bloom), you need to use Emission textures. I'm not sure the effect you're going for on your screen, but only one of your screen "textures" has an emission, but it's mixed with Diffuse and it's kind of hard to tell what it does. The other texture has simply a purple Diffuse shader. If you switch that purple Diffuse Shader for a purple Emission Shader and turn up the strength to something like 10, you'll see it glow.

ohh ok thank you ill try that


text:
How to create the expression of three layers of sheets becoming soft and crushed?
I'm trying to make an animation like this (see the image)

I am currently using Fluid simulation to create this animation.
But I'm having trouble figuring out how to make it work because I've never heard that you can only use one liquid and not three.
(Am I right in understanding that in Fluid Simulation, multiple Domains cannot coexist, and there must be only one Flow (Liquid) corresponding to a Domain?)
My idea is to render each layer with a background transparency and combine it with the background, etc. to make a single video.
However, I think this method will inevitably result in a sense of discomfort.
Is there a better way?

You could try Flip Fluid addon, it's paid but has a demo so you can generate color attributes for your layers and use that in cycles... but colors will tend to blend. Not sure a fluid simulation is a good solution, maybe use it as a reference and then fake it with lattice modifier and shapekeys?

@calambre So sorry for late reply. And thank you so much for polite message! I checked about Flip Fluid, but it is little too much for me.. Then I tried lattice and shapekeys! And it worked!! I really apliciate you! I was pressed for time so you save me!

ok, good it worked for you!

source: Stack Exchange

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

sort: votes


text:
The cursor to selection command doesn't consider the normal direction of the face
gif A) The cursor to selection command doesn't consider the normal orientation of the face.
gif B) You can use the Cursor tool with Geometry as the Orientation option to get the normal orientation of the face, but you cannot position it exactly in the center of the face because you position the cursor manually.
Do you know how to improve this problem?

gif A

gif B

worse filling a bug?

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


text:
Alpha texture images appear lighter than the original image
I drew a cube in the 2D drawing tool and printed it out as a png file, and imported it into the blender using the Shift + A, Images as Planes function.
But here is the problem.
The imported image is lighter than the original image.
Please see the attached screenshot.
The image opened in Paint on the right is the original.
The Reference object next to it accurately displays the original image.
However, the three Image as Planes objects on the left are displayed lightly.
Perhaps the texture responds to the environment, but I wonder if even objects with shadeless and emit options react to the environment.
How can I solve this problem?

To help you write your answer, I have uploaded a blend file containing png images.

Screenshot for additional questions about Leander's answer :
The Color Mnagement> View Transform> Raw option causes the black and white alpha textures to appear the same as the original image, but for color images, the colors appear darker.

I think you have to undo the viewtransform. E.g. if you switch to RAW via the Properties > Colormanagement >View Transform, the images display the same as the reference.

@Leander
That method has its limitations.
Of course, the RAW option displays the cube picture the same as the original image, but darker for other color images.
I have attached a new screenshot in the text.
Please check.


text:
The Blender Image Editor's zooming feature has rough filtering than other 2D software
I loaded an image to the image editor for reference and scaled for fit my screen it.
And I got pretty rough filtered view.
Other 2D software shows smooth filtering.
To help you understand rough filtering, I filmed comparative GIFs on Blender, Photoshop, Krita, and TVPaint Animation.
Is there any option I missed on the blender? Or is it the limit of the blender's image editor?
I used Blender 2.92
Blender

Photoshop

Krita

Tvpaint Animation


text:
I would like to make a wrap animation

I would like to make a gif-like animation.
I tried using cloth physics, but I found it difficult to express the point where the cloth is in free fall and the vinyl is stretched.
If you have any recommendations for me, I would appreciate it if you could let me know.

I will post the YouTube that I referred to.
●Wrap ANYTHING in Plastic Procedurally in Blender - TUTORIAL
https://www.youtube.com/watch?v=gPyRRR1lLcg&ab_channel=Simon3D
●Create Motion Graphic Animations with the cloth modifier | blender tutorial
https://www.youtube.com/watch?v=IRYA69lWET0&ab_channel=3Dschool

i don't know how perfect it should be, but maybe just a plane with some hooks animated is the much easier way doing it....?

Sorry to be selfish, but I want to make it almost perfect. However, I don't need the expression at the end of the movie where the roll is stretched like rubber when pulled and then adheres to the roll.
I couldn't get the roll and Wrap to be close together using the shape keys method, and it was difficult to animate it using the shrink wrap modifier method.
I have added the YouTube link I used as a reference if you would like to see it.


text:
I would like to adjust the distortion at the curve point of the curve modifier
Please see the image.

I am making Conveyer Animation.
I want to adjust the parts and conveyor to fit as shown in the image.
I have created a single object with two modifiers, 1. Array:Fixed Count and 2.
I am currently adjusting the spacing between the parts using the Relative Offset of the Array Modifier of the parts, but when the Curve is bent, it shifts.
Could you give me a good solution?

Can you share the blend file ? https://www.pasteall.org/blend

Thanks for replay! I added blend file!

You have not given the same curve as Curve Object for your 2 objects (Belt Conveyer and Parts.001), if you give them both the same Curve Object they will synchronize correctly

Sorry for late reply.. It worked! thank you!!

It's as @moonboots say, you have two different curves for the two objects, by using the same curve (I used Belt Curve for the two), they synchronize :

Also, your animations don't line up, the cubes went clockwise while the belt goes anticlockwise so I reversed the cube's animation to follow the belt.

Sorry for late reply..  Thank you so much!! It perfectly  worked!

You're welcome.


text:
How to make stick person like Japanese samurai
I want to make stick person like this image.
But I don't know how to make his back hair (not top hair=chonmage).
I thought, make UV Sphere and extrude  back hair part.
Then I realized, I can't extrude in a curved shape.
So.. Please teach me; ;
Blender 2.9.2
Windows 10

"Then I realized, I can't extrude in a curved shape", what do you mean by that? Maybe you want to extrude along normals, (alt e > extrude along normals)

@Alexbries
Sorry for bmy bad English. That's not what I want to do.I can't make a smooth curve because the surface is square. (Please take a look at the added image)

Create the sphere, then create a different object (i.e. a plane), use the face snap option (project individual elements) and model the hair snapping every vertex to the underlying sphere.
Then add a mirror modifier for the back of the head, a solidify modifier to get thikness, and a subsurf.

Omg Thank you so much!
Did you make under 30 minute! wonderful...!
But I wan to ask you more...
I did snap plane to sphere but it's not perfect.(please take look at added image)
So should I fix it by moving the dots one by one in edit mode?
And I want to ask you how to make a beautiful curve from a straight line?
(Around the ears and around the neckline)

I can't add image so please take look at image from this URL
https://ibb.co/GFL5ZRs

Yes, moving and extruding vertices one by one in edit mode with face snap enabled will force them to snap to the sphere. Then a simple subsurf modifier (in my example level 2) will transform jagged lines into sweet curves.

Helol Josh, finally I completed thanks to you!
https://ibb.co/5k26MCr

Very nice! You're Welcome.


text:
I want to roll the tape so that it follows the circle nicely
I want to roll the tape so that it lines up nicely with the cylinder.

When viewed from the front, the surface where the tape meets the cylinder is distorted as shown in the image.

Currently, I manually adjust the curve to follow the circle and add a curve modifier to the tape.
Is there any way to semi-automatically make the tape follow the circle?

I meant that I am looking for a way to make the CURVE in the following article follow the cylinder in a non-human-powered way.
●The article
I need to make the vertices of a mesh follow a path / curve so that the mesh deforms as it follows the path?

just increase the resolution preview of your curve:

or/and the resolution U:

Thank you so much!!! It's smooth now!
However, I have one more question. If I want to follow many curves on a cylinder like this, it is very time consuming to adjust them manually, and it is difficult to follow the circle nicely. Is the SNAPS function the only way to do this?

Hi Hana. If my answer helped you, pls click on the checkmark left of my answer. Thank you. Pls do not ask additional questions in comments because other people might have the same question and won’t find possible answers in comments because the search engine of SE does not search in comments. You may ask as many questions as you want. Thank you for your understanding.

Sorry!
Thank you so much for your kind attention!
I'll ask the above question again if I'm ever in trouble again!
thanks again!


text:
How to use Multires "Apply Base" with shape keys?
Multiresolution modifier's Apply Base button does nothing when the mesh has shape keys. Is there a workaround?

It's possible to work around this limitation as following:

duplicate the mesh
apply shape keys and perform Apply Base on the new mesh
create a relative shape key to the original mesh from the new shape of the new mesh
copy multires data from the new mesh to the original mesh

The third step needs an add-on. Corrective shape keys is simple, so I'll use it in this answer, but I'm not sure how reliable it is. The Pose shape keys add-on seems like a more modern and solid alternative, but requires several extra steps for this use case.
Starting point
Initially we have a plane with a diagonal ridge in the base mesh (aka the mesh visible in edit mode):

There is also another ridge in the opposite direction done in multires only:

We want to perform Apply Base such that the base mesh gets a second shape key that matches the shape of the second ridge. We don't want to lose existing shape key. Steps:
Steps

Install and enable Corrective shape keys addon.

Duplicate the object as Plane.001, apply shape keys, and click Apply Base. Base mesh has now changed appropriately, which you can see if you disable the Multires modifier.

Re-enable Multires modifier in the duplicate object. Disable Multires modifier in the original object (otherwise next step will fail).

Select the duplicate and then original object. Create new shape key and set its strength to 1. Select Shape Keys > Specials > Add as corrective pose-shape delta. The mesh will now look right.

Enable Multires modifier in the original object. It should look deformed, because the second ridge shape is currently both in base mesh and multires data.

With the duplicate object still selected and the original active, click Reshape under the Multires modifier. The original mesh should now look correct.

You're done. You can verify multires data contains only the minimal amount of changes relative to the base mesh by disabling both shape keys.


text:
Name not reflected when generating nla strip with Python as strips.new() method
I looked at the api document and expected the name parameter of the strips.new() method to be reflected in the name of the strip, but it wasn't. Did I misunderstand anything? What is the purpose of the name parameter of the strips.new() method?

I tried to explicitly indicate the parameter name, but it didn't reflect the name either.

I tried, but it doesn't seem to work. I added the test contents to the body.

IIRC has been asked before it is being given the name of the assigned action.   Can rename the action, eg name the action "Walk"  and first strip with that action will also  be "Walk" or (as suggested above by G) rename the strip after creating.

ie strip.name = "Foo"

"What is the purpose of the name parameter" Nothing, it's unused.

Oh wow.. I didn't expect to see the C code. I feel like I've swallowed a red pill.


text:
Armature custom properties?

Custom properties added to the armature tab do not appear on the item tab of the 3d viewport side bar, unlike the object tab and the bones tab.
I’m curious about how to check armature custom properties and examples of using them.

Codewise if ob is object ob.data is armature and ob.pose.bones["Foo"[ is active pose bone, the custom properties are ob["prop"] (object) ob.data["prop"] (armature) and ob.pose.bones["Foo"]["prop"} on the pose bone.  The custom property of a "data" part ie mesh, armature lattice are displayed generally only in the data properties.

Oh, codewise! I understood. There's nothing to use for general rig manipulation.


text:
How to activate a bone in pose mode with Python?
summary
How do I activate a bone in pose mode with Python?
Specifically what I want to do

I have many bones that have child of constraints.
During the process of setting characters, I often need to click Clear Inverse / Set Inverse buttons of those constraints one by one for all, so I want to write a script for batch processing.
Below is the code I wrote. I've got a list of bones I want to iterate over and the code for Clear Inverse and Set Inverse is also available, but I'm not sure how to activate the bones to apply the operation to.
What code should I write on the commented line?

import bpy
my_bone_list = bpy.context.selected_pose_bones
for i in my_bone_list :
    # Activate the bone assigned to variable i from my_bone_list by the loop
    bpy.ops.constraint.childof_clear_inverse(constraint="Child Of", owner='BONE')
    bpy.ops.constraint.childof_set_inverse(constraint="Child Of", owner='BONE')

Thank you in advance.

Pretty well explained in Set active bone in pose mode from Python script. C.active_pose_bone should do it right?

As far as I understand, what the link describes is actually select, not active. The bpy.ops code works for active bones, not selected bones. Therefore, I actually wrote and tested the code in the way suggested by the link, but did not get the correct result. Please tell me if there is something I misunderstood.


text:
Driver-controlled mask modifier visibility / rendering causes pop effects
I am working on a stop motion style animation project.
To implement on / off toggles for facial expressions and hand-held props, we applied a driver controlled by a custom property to the mask modifier.
I finished rendering the keyframes for the animation and found that there were pops in some sections.
For example, facial expression A and B are displayed at the same time in the one frame where A changes to B, or a prop in the hand that was suddenly turned off in one frame appears and disappears.
All keyframes have hold interpolation.
Perhaps there is a problem with the driver update.
Q: My rig needs visibility / rendering toggle for facial expression, props or costume.
Mask modifiers, however, cause pop effects.
Is this a bug or a known limitation?
What is the best way to do it?

I followed Serge L's advice to check for errors in the system console and wrote the addition below.
Check the following error message.

I thought the mask modifier was the problem, but I was surprised to see the error related to binding.
I checked the character file and noticed that the eyes object has a modifier set up as shown in the image below.

But there is some doubt here.
The vertex count of the eyes object is not 6418.
I examined all the objects in my character but none of them had a 6418 vertex count.
I put the mask modifier on the eyes object last but I still see the same error on the system console.
On the other hand, the biggest question is this.
My rendering error occurred on a mouse object.
The mouse object was changing shape by a lip-sync animation, but when I checked the rendered PNG sequence, it was rendered with two mouths overlapping in a frame.
When I re-rendered the frame without modifying the blend file, it rendered correctly.
As such, the driver update missing I've been experiencing happens randomly.
The mouse object does not have an armature modifier and is just bone parented.
Can a vertex count mismatch of an unknown object with 6418 vertex counts miss a driver update for a mouse object that seems unrelated to it?

If you manually keyframe instead of driving, will it go smooth? Drivers are buggy if cycle dependency is present, open system console to to check for errors.

Yes. In my experience, keyframes were no problem.
The problem came from using the driver.
As your advice I have checked for cycle dependency errors in the system console.
I wrote an addition to the text, so please confirm it.

Bind errors usually come from modifiers utilizing binding such as Corrective Smooth, Surface/Mesh Deform, etc check if you have any. Also put a pic of driver's expression from graph editor.

@SergeL I'm sorry I came back late. The project has been completed and a new project has been started quickly. I want to study deeper into dependency errors, but I can't afford. In my next project, I will always keep an eye on the system console to manage the blend file so that there are no error messages, and I'll see if the mask modifier's visibility causes driver update errors even in clean blend files. Thanks for the hint.


text:
How to map vertex to particle (hair); or color particles with specific colors
I am trying to render CFD data in blender, where the CFD code generates output files that consist of particle positions and scalars. I have successfully loaded the data into blender and used a particle system to place a sphere at each vertex. Next, I want to color each particle using a scalar (temperature, velocity, etc.). So I created a nparticles x 1 image where the colors are the same order as I added the vertices. I tried using the particle system index to map to that image and color the particles. This works except that something in the ordering of the particles is wrong.
This image should have a nice linear coloring from bottom to top based on the particles height, however it has bands of color:

Here is the material nodes for the duplicated object (sphere):

Any ideas on how I can map the vertex order to the particle order?
Most of this has been derived from this add-on: https://github.com/SBCV/Blender-Addon-Photogrammetry-Importer/blob/master/photogrammetry_importer/utils/blender_point_utils.py
For creating the image:
def set_image_data(obj, data, cmap='viridis', limits=[0, 1]):
    '''
    Given an array of data, convert to colors using the color map, create an
    image and asign the image to the 'Image Texture' node in the objects
    material.
    '''
    node_tree = obj.data.materials[-1].node_tree

    data = data.flatten()
    npoints = len(data)

    # create the image to color the objects
    w, h = npoints, 1
    image = bpy.data.images.new('ParticleColor', width=w, height=h)

    # map data to colors
    rgba = map_colors(data, 'viridis', limits)

    # set the pixels
    image.pixels = rgba.flatten()

    # add image to Image Texture node
    image_node = node_tree.nodes.get('Image Texture', None)
    if image_node is not None:
        image_node.image = image

    # update divide node
    math_node = node_tree.nodes.get('Math', None)
    if math_node is not None:
        math_node.inputs[1].default_value = npoints

For creating the particle system:
def make_hair(parent, child, npoints=100):
    '''
    Make a Hair particle system, inspired from:
    https://github.com/SBCV/Blender-Addon-Photogrammetry-Impoarter/blob/master/photogrammetry_importer/blender_point_utils.py
    '''
    parent.modifiers.new("particle sys", type='PARTICLE_SYSTEM')
    particle_sys = parent.particle_systems[-1]
    settings = particle_sys.settings
    settings.type = 'HAIR'
    settings.use_advanced_hair = True
    settings.emit_from = 'VERT'
    settings.count = npoints
    settings.hair_length = 1  # This must not be 0
    settings.particle_size = 1
    settings.use_emit_random = False
    settings.render_type = 'OBJECT'
    settings.dupli_object = child

Why do you use Image texture? Divide node should output nice gradient on its own, just plug Colorramp before shader to colorize it.

This is just an example. In the real application I have an array of data (particle temperature) that I need to map to specific particles. So something like particle(50) has a temperature of 600C...

Maybe 32bit depth will help when creating new image, float=True. Also uncheck "random" emission in particle system.

I am using 2.79 (Latest that works on our machines) so I tired float_buffer=True when creating the image. That didn't seem to change anything.


text:
Fix missing parts of humanoid
My model is a sitting humanoid. You can see a video here, which shows the problem perfectly:
https://drive.google.com/open?id=1FcmjXTwH0bRUUeM3XCI1i6FRBi-wFu-3
The model is to be used as an enemy in a unity game. Those parts should be fixed in such a way you would expect it to look like if the missing parts were there.
Your brain already completes it, this is what the model should look like. I created an example outline on the right upper arm of the creature.
Example: arms are round. You only see parts of the arms, sometimes more, sometimes less. In an abstract way, arms are cylinders. So there should be cylinders as a rough guide along the fragments. As I wrote, your brain knows it already what it should look like.
My question also adresses the painting of the non-existing parts to make them match.
How do I fix the missing parts efficiently the way described, so it looks like a sitting humanoid?

Welcome to Blender.SE. Could you please add some info about the final usage of the model? What kind of mesh are you expecting? And how you imagine those parts should be fixed?

@cegaton You have all the data to answer the question. I made enough effort, now it is your turn.

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


text:
Rotating a cylinder distorts it
When a cylinder is rotated, it is distorted and does not rotate cleanly.
The scale, position, and rotation values of the cylinder are set to 0 or 1.
The origin is also set to be the center of the cylinder.
What could be the problem?

create a new cylinder without textures and rotate it. same problem?

The bug does not occur in the new cylinder.

Then it sounds like your cylinder isn't actually a perfect cylinder. Select all the edge rings on the mesh that make the cylinder circular and then use Loop Tools > Circle to even those out. Then Shift+S > Origin to Geometry and see if that fixes things.

Thank you so much...!!

the problem is, that your cylinder is not aligned to the axis you are rotating.
If you look from above (7) you can see this clearly:

Ohh I don't know why I did not realize that... but thank you so much !

you are welcome


text:
Rendering starts, but data is black
Rendering starts, but data is black
When rendering is started, it starts without problems and the render screen is displayed correctly, but as soon as rendering is finished, the screen turns black. Of course, the data is also black.
I tried export formats such as PNG and mp4, but all remained black.
Other projects render fine, so I think the problem is with this project, but I don't know what the problem is...
The data is so heavy that I couldn't post it on this site, so it would be helpful if you could check it from the Dropbox URL.
https://www.dropbox.com/s/5mlrd1gal40j3i6/220301_Purfume_RENDERTEST_light.blend?dl=0

Hello and welcome.  Can you [edit] your question to include a picture of your compositing workspace?

Thank you. I added a picture but I don't know this is what you want.. sorry

Try the Image output instead of Noisy Image output from Render Layers.
I don't think Noisy Image exists in newer versions of Blender, but the socket may still appear under some conditions.

Thanks for reply. I tried it and it worked!!! Thank you so much!! I decided to study about Node as soon as possible...! Thanks again!!


text:
I would like to apply the simulation of softening, melting, and extrusion only to the part that is pushed
Please see the image of the animation flow.
Object A comes down from above, pushes objects B, C, and D, and adheres to object E. At this point, objects C and D soften and melt.
At this point, objects C and D become soft and melt. (They do not become liquid. Image of very soft slime)
Object B is unchanging.
In addition, object A pushes objects B, C, and D, causing some of the softened and melted objects B and C to be pushed outward.
However, only the parts of objects B and C that are softened, melted, and pushed outward are the parts that object A touches.
As a result, the layer consisting of objects B, C, and D becomes a layer about 2/3 of the thickness.
[Question]
How do I specify that only the parts of objects C and D that touch object A should change? (Even if I select some of the Vertex in Edit Mode, Physics could not be applied.)

There are some rule in this site. I didn't make the rules and i cannot say i like them...but i think they will close your question. One rule is: you should only ask one question. You asked at least 4 questions...

Thanks! okay I got it

one possibility (of several) is to use a liquid with some viscosity settings.
You can even animate the viscosity (so high value before the cylinder press hits it and less high if it hits).
Here are some examples of different viscosity, in which i pushed a cylinder from above (as you did in your sketch):
Viscosity: 0.01

Viscosity: 0.05

Viscosity: 0.1

Viscosity: 1

Note: with the current state of the physics engine i do not think that it is possible to make this all with one simulation. So i think you have to "kind of" fake it. That's what 99% of all blockbusters do and that's what vfx is ;)

Thank you very much for your detailed answer.
I had no idea what I was doing, so just knowing that this animation could not be expressed in a single simulation was a very useful hint.
I'm going to bed now, so I'll try it tomorrow and get back to you.

Mr. Chiris
Good morning.
I've been researching and trying Quick Liquid, but I'm having trouble getting the animation that you've shared.
Also, am I correct in understanding that you are using the Force Field Wind to push the center part from above?
Is there anything else I need to set other than Viscosity in Liquid?
If you don't mind, I'd like to know the values you set.

I have researched and found that Force Filed does not affect Fluid(Liquid), but how do you recess the center?
Just adjusting Viscosity doesn't make it look like the gif you shared.

you are right, sorry, forgot to mention that i pushed a cylinder from above in the fluid. Added the blend file and corrected my text.

Thank you so much!!
I've been eagerly awaiting you...!!
I will try the blend file now.
I will reply again.

Sorry for the late reply.
I've got the general framework as shown in the GIF, but I still have a problem: 1.
I want to make it look like C and D are hard (keeping the shape of the square) until object A and C and D touch. (Even if I set the viscosity to 5, which is the maximum, it still looks soft...)
Or can I set the start of the simulation to any frame instead of tweaking the simulation settings?
Image:https://ibb.co/QMNH9rV

Yes you can. It is in the domain settings. Open Cache settings.

Ohh it worked!! Thank you so much again!!

Glad I could help. Please click on the checkmark left to my answer, if it helped you. Thanks

Ohh sorry I forgot it! Thank you Mr. Chiris!

you are welcome


text:
I would like to export a video with a transparent background so that it doesn't get laggy
I can export the file with a transparent background, but when I play it using VLC media player, it is very choppy. I would like to make it play smoothly.
I'm currently rendering with the following settings
Transparent: ✓
Color: RGBA
Quicktime, OT rle / QT Animation

I've tried setting the Keyframe Interval to 0 and exporting it, but it didn't smooth out.
What is the problem with this?
This is my laggy movie.(This is famous File Transfer Service)
https://4.gigafile.nu/0223-d6710b3301cca03e2eaa83d962a32517e
you can download from this button.

I could not solve it by using Quicktime. Realtime compression and 64 render samples gave me half-smooth half choppy render, but it's not enough. There may be a bug in the encoder.
However, it worked fine with PNG, RGBA, %0 compression. And, you have more control over your video when you render it as an image sequence.
You can import PNG sequence to Blender and export it again as a video file format, or you can use other video editing softwares to give its final shape.
Does that solve your problem?

Sorry for late reply.
And thank you so much polite answer.
Actually I tried to export as PNG then export it again as .mov or .avi something.
But nothing changed...
Can you tell me what Output Properties you used to export the PNG as a video?
I usually output PNGs as mp4, so I know how to do it, but mp4 is a codec that doesn't support background transparency, so I need to output it as mov or avi, and I'm surprised how hard it is...

Sorry, I forgot to say that I've changed the Keyframe Interval to 0. It did not work in Quicktime but worked in PNG for me. Also, I've done this in both Blender 3.0.1 and Blender 3.1.0 Beta for MacOS Arm versions. Which version of Blender are you using?
To export RGBA video, I usually import the video to After Effects, export to Adobe Media Encoder then Select "Quicktime -> Animation" with "alpha channel". This always work for me.

Thanks for reply. Is it correct to say that after exporting as PNG, I exported the mov file using Image Sequence with the keyframe interval set to 0, and it became smoother?
I've tried with 3.0.0 Alpha/ 3.0.0/3.0.1, but none of them worked.
I'm using Davinci Resolve, so I tried that too, but it didn't work because the background transparency turned green, so I'm thinking of completing it on Blender.
(I wish I could use Adobe, but...)

I've downloaded the Da Vinci and imported sequence to it. I had no problem like green background or whatsoever. With these settings, I got a clean render with alpha: Format: QuickTime, Codec: Apple ProRes, Type: Apple ProRes 444, Export Alpha: Checked.
It seems like the latest Da Vinci has a problem with image sequence imports. It does not detect the image sequence, so I've imported all the PNGs to media window. Then go to Preferences -> User -> Editing -> General Settings -> Standard Still Duration -> Frames: 1. I've done this because every PNG frame on the timeline is 5 seconds long.

Can you get clean exports with PNG settings right now? I've written the above comment as you are clean with PNG export. Please tell me if there is still a problem.

Oh, thank you so much for testing to use DaVinci Resolve. I tried it but I use windows so I can not export as Apple ProRos..(Sorry I should mentioned it before...)
I got clean PNG by your settings. I keep try to find the solution. thank you.

I cannot use my Windows PC right now, so I cannot try it. But last week, I had clean alpha renders with the encoder I've mentioned above using Adobe Media Encoder. ProRes is not MacOS only encoder. I cannot check it right now, but Da Vinci probably has that encoder in Windows. Did you check it? It would be bad not to have that in the Windows version of Da Vinci. I was thinking about changing my workflow into Da Vinci.

I see. I don't know this way is best or not, but I found this video about how to export Apple ProRes in Windows. I use DaVinci Resolve Studio(need licence) so I could use this addon. I got ProRes video. but it still choppy. So I tried other codec AVI, that looks smooth for me. But I can not import that avi file to DaVinci Resolve. So I am trying to find the solution now. BTW, I recommend DaVinci Resolve to use as render. If you make video for YouTube or someting, I recommend Adobe.

As I mentioned  before, export the video in DaVinci Resolve, it looks wired green background. (you can see here https://www.dropbox.com/s/mu9b3jm1scxqq68/laggy.mov?dl=0) But when it import to DaVinci Resolve, it looks perfectly transparent. I can not understand what is happen... https://www.dropbox.com/s/c90olthkq5x3fcd/Screenshot%202022-02-16%20194030.png?dl=0
(I used export setting→quicktime/Grass Valley)

Sorry for many reply. Finally I found the answer. I export in DaVinci Resolve as below setting. Frmat:QuickTime, Codec:DNxHR Type:DNxHR444 12-bit Export Alpha:✓
Thank you so much for so many anwer. I could not reach this way without you, Mr. Hazer.  Thank you so much!!!!
https://www.dropbox.com/s/r5bxqjghp0dirob/Screenshot%202022-02-16%20194544.png?dl=0

I've found another solution. Render your .blend file with these settings => File Format: FFmpeg Video | Encoding -> Container -> Quicktime | Video -> Video Codec -> PNG | Encoding Speed -> Realtime (this is for me to get quick result) | Color -> RGBA (this becomes available after you choose video codec as PNG) | Keyframe Interval -> 0. With this way, I got clean render and you don't have to work with another software. Can you check it?

Ohh Thank you!! I will check it soon! Thank you so much again...! ; ;

Your solution is perfectly worked!! this way is better! it save my time a lot. I've never seen polite people like you. I don't know how to say but... Thank you so so much!!!

Glad that it worked! Cheers ^^

Cheers!!!


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I want to use fog to show that it is heated

I want to create a fog like a Gif.
I tried to make it with volume node by referring to the Tutorial, but I am not satisfied with it.

Would it be better to use a simulation?
If you know a better way, please let me know.

Reffer Tutorial
https://www.youtube.com/watch?v=MoggY_6v5qQ&t=229s&ab_channel=RyanKingArt

You could create this node setup: Noise Texture > ColorRamp > Emission > Volume input of the Material Output. To animate it, keyframe the position of the ColorRamp needles, the W factor of the Noise Texture (set to 4D), etc...:

If you use Eevee it will need a bit more tweakings: In the Render panel, under Volumetrics, lower the Tile Size down to 2 and increase the Samples to have a better resolution (and also the Distribution value if you can't see the result in the camera).
If you don't want your fog to emit any light, use a Shader > Volume Scatter instead (or a Principled Volume) and plug the ColorRamp into its Density input:

Thank you so much for plite reply!
I tried your way!
Image : https://ibb.co/fNzZgQ4
but I would like to ask you more 2 questions,
1.I want to prevent fog from penetrating through it. (I want the fog to be invisible where there is a metal box in the foreground.)

The color is a little light, perhaps due to the light, so we want to make it darker (we have selected a darker color in node's color ramp).

I am sorry for the repetitiveness of this question, but I would appreciate your response.

Hello, what do you mean, penetrating through what? The fog will stay within the shape that you'll give to your object. For the color, please see my edit

I would like to hide the fog about the circled area of the image.
In the first Gif I posted, you can't see the fog in the area that is covered with the box. I want to do the same.

I have added a blendfull and would appreciate it if you could tell me what is wrong.

@Hana It looks like it has to do with the Distribution value in Render panel > Volumetrics, try to lower it down

So true!
Thank you so much for all your kind words!

Note that in Eevee by default you can only use cuboids for volumetric, unless you use Volume Empty

Thank you so much again!
I tweaked the numbers after that and got an expression I was happy with! Thank you very much

@Hana Glad I could help  ;)


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I cant disable Proportional Editing
So I was making a car, but I couldn't move a vertice. I saw that someone else had said this question and one person said to turn off proportional editing. But when I tried it wouldn't turn off. I unchecked the box that said proportional editing, but when I came back to make sure it was unchecked, it would still be checked. EDIt: It if off, but when i move any edge, vertice, or face it automatically turns on.

Have you tried hitting 'o' on the keyboard? That's the default shortcut to disable proportional editing

Yes, it but it doesnt work. Also tried Alt+O

I opened blender again, proportional editing is off, but when i   move the vertice, it turns on automatically

Interesting... I haven't had that problem, and it doesn't seem to come up a lot. There are a few similar bugs posted on developer.blender.org:
See https://developer.blender.org/T64019 and https://developer.blender.org/T64011

Same bug for me. Can't disable it

Same here in Blender 3.0, Proportional Editing comes back automatically in object mode.
My workaround:
Go in Edit Mode, toggle Proportional Editing on and off.
Back to Object Mode, select one or two bones and Proportional Editing seems to work normally after that.

I think the real culprit might be the Mirror option under the Options dropdown in each viewport.
I have no idea why it's sometimes turned on, maybe a cat walked on my keyboard. But when random vertices are moving when I don't want to, it's usually that. It needs to be turned off for every object individually.


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why dosen't the motor constraint work properly?
I made a simple car with physics and rigid body constraints. The car can go downhill, but I wanted it to go uphill. so I added a motor constraint with an angular velocity of an inpulse of 10 and a max inpulse to the wheels. I connected the front wheels with the body using motor constraint but the motor constraint makes the body go forward, but the wheels keep rotating in the opposite direction of what it should be. I tried rotating the empty, but that just makes the body go backward and the wheels rotate forward. I have the body of the car selected for the first rigid body to be constrained in the motor parameters and the wheel on the second rigid body to constrained for every empty.

Hey there, welcome to the Blender Stack Exchange! I'd like to help, but I'm not sure what you mean by "motor constraint" because there isn't a constraint with that name as of Blender 2.92. Could you try adding a minum reproducible example?

he means the rigid body constraint - type motor


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Best way to tile a complex shape with a texture?
I want to take a texture, say a basic black/white checkerboard, and apply it to a complex shape (a bit of level geometry for a game in this instance). At the target scale, it will be much smaller than the target object, maybe 1/5th of the width of the bottom square area in my image, but it should tile to fill.
Deformation is not desired, so for example even if there is a hill in the geometry the checkerboard texture should be the same as-the-worm-crawls distance from square to square everywhere.

I have tried fiddling with texturing options but it seems mostly it is made for simple shapes, and treating this shape like a cube or sphere leads to understandably strange looking results.
I also thought about getting orthographic projections and applying UVs but it seems like a bit of an intensive workflow and it will also lead to deformation in the shape when texturing hills and the like.
Below is the actual kind of end result I'm going for, so eventually I'll also want to find a way to tack on these "edges" to the shape, but for now I'd like to just start with a looping texture. Note that because my target end result looks like this, I only care about the top and bottom of my shape separately when it comes to looping textures and thus there doesn't need to be consistency between the sides.
Any advice would be appreciated! I'm very new but I know that I could do this already in one of several painful ways. I'd rather do it right, from the beginning since I will have to generalize this process to many other geometries later on.

Edit: Here is an example of the simple approach of getting a UV map from an orthographic projection causing some warping on slopes, which I'd like to avoid if possible.

I do not understand the “as the worm crawls description.” Hills will not be able to have a perfectly tiled texture, because you cannot make them out of a flat piece of fabric without cutting. The attached screenshot’s textures only work because the curved terrain is bent along only one axis.

Oh, hm. I suppose that is true. In that case I can accept deformation, but not in the case that a curve is only along one axis. I meant hill more like a slope that is pictured here but I didn't really think about a 2-dimensional hill when I wrote it. In the image I think it should all be able to be textured with no deformation for example (also the checkers needn't perfectly fit into the contour of the shape and can overflow a bit if needed)

Ok, well, sounds like a standard UV map, possibly with “repeat” set for image input mode.

Therein lies the question - how would I set up the UVs to make sure that I don't warp the hills (here I mean just the 1-axis slopes)? If I get UVs from an orthographic projection looking down -Z I will see the hills as flat and thus the checker texture would be messed up. Is there a way to do a "distance sensitive" solution here?

@EmptySet The standard UV ▸ Unwrap operation is “distance-sensitive” in the way you describe.

Perhaps I don't know what selection to do that operation on. Doing that with all faces selected yields a mesh that overlaps itself in weird ways and would be hard to get neat orderly checker patterns to map onto I assume. Doing it "from view" on an orthographic projection gives the warping I showed in my question. Doing it on just the front faces yields something that does not seem to be distance sensitive. If you can give an example procedure including the selection process I will try it out though!

I think a simple unwrap would do just that. You just need to set all the outer edges of your shape as seams, so the UV unwrap 'knows' where to separate the shapes (UV islands) and avoid distorting and overlaping in the UVs.
To set edges as seams: in edit mode, select only the outer edges of your platforms and then click on "edge" and "mark seam".
Then select all faces, hit "U" and "Unwrap". I think it should give a pretty good result. Might need to tweak a bit in UV editing, like rotating the islands so they align with the texture pattern and stuff like that.

Thanks for the feedback. I tried it out and it was a bit of a mess but I think the solution is going to be simpler, more modular geometry plus an approach like you mentioned.


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Using a 32 bit grayscale TIFF in the displace modifier
I have a problem with very obvious banding showing up when using a TIFF generated from an Digital Elevation Model in ArcGIS. The image you see uses an exported 24 bit TIFF. I think it could be solved if I can use an exported 32 bit grayscale TIFF from ArcGIS, but this won't load in Blender. I can also export the height data as an ASCII file, but see no way of using this, except by maybe writing a Python script.

I've read something about Blender being able to use OpenEXR, but I can't figure out how to convert my TIFF to this format. I'm on a Windows 7 machine. Can anyone help me, or know a way to solve this without converting to EXR?

You say the above image doesn't load in blender, what error are you getting? What options do you have when exporting?

The image you see above is with a displacement map that does load, however due to it being low bit depth you get the obvious banding on the plateau at the top.
When I try to use a 32bit TIFF it doesn't load correctly. I get no errors, but no displacement either. I can export a number of different formats, but TIFF is the only one supporting 32bit.

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


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Is there a way to change the color wheel used in the node editor?
I really dislike the color wheel for picking certain colors, especially browns. I would really like a few more options to pick the colors. A large amount of swatches would be especially nice. Now I often go to a site listing color codes and copy paste these into Blender, which is a laborious process.

For brown, just go to red and reduce the value(slider on the right). If you can come up with a way that allows full control over the hue, saturation and value in an intuitive way, let me know, 'cause even Photoshop failed at that...

You can choose from four different color picker types in the user preferences:

Perhaps you like one the options better:

You might be also interested in the Palette addon which only works only in paint modes (Image Painting, Texture Paint, Vertex Paint, Weight Paint)


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Is it possible to use a texture to control the size of particles?
I'm trying to make a forest with a particle system, but I want a controlled variation in tree size. Is it possible to use a displacement texture or something similar to control the size of the particles?

This method also allows for controlling size of particles.

Just add a texture to your emitter and in the influence panel of the texture choose Size for emitter particles or Length for hair particles.


text:
Cryptomatte is showing the same color for different materials?
I am using cryptomatte. That mostly works fine for me but I found it uncomfortable sometimes. As you all know, the pick color of Cryptomatte depends on the name of the material. The problem is that sometimes Cryptomatte gives the same color for materials with different names.
Please see the attached example:

I deliberately renamed the material to reproduce the extreme case. Notice that the pick colors of all six cubes in the Cryptomatte node are all white. This is on the easy side. Imagine a situation where you pick adjacent materials that are adjacent and have the same pick color in a much more complicated scene. You can change the name of the material to avoid this, but I think it's not a good idea to rename a material that's named according to the rules that make sense for any project.

Q: Is there any solution for this case? Has anyone else experienced this inconvenience?

I've written more about thibsert's comments below.
My viewer node's display channel option is set to "Color and Alpha" rather than "Alpha".
The new GIF below shows that.
In addition, it shows that the color of the cryptomatte pick color changes when the material is renamed.
A new color has appeared but still pick colors that have the same color in two adjacent cubes in the top right corner.
In particular, in my experience, the pick colors of background objects and small props were often displayed in the same color, which was inconvenient.

Please make sure your viewer Display Channel isn't set to "Alpha" but to "Color and Alpha".

@thibsert Of course thibsert.
My viewer node display is set to "Color and Alpha".
I have attached a new GIF at the bottom of the text to prove this, so please check it.


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Cryptomatte Boundary Artifacts?
I got Boundary Artifacts while using Cryptomatte.
I wrote a question on the same topic, and I read a comment that low resolutions could be an issue, and added a resolution perspective to write more specific questions here.
Rendering was done at 2560x1440 and layered the image using an Alpha Over node that takes the Matte output of the Cryptomatte node as a factor.
Even when working at high resolutions, the 1px Boundary Artifacts are still noticeable, and the more distant the object from the camera, the more vulnerable it appears.
How to use Cryptomatte correctly?
I've attached images and blend file to help you understand.
ⅰ) comparison of the original and processed images

ⅱ) Compositor node tree

ⅲ) processed image with 2560x1440 resolution (Click for larger screen please.)

ⅳ) blend file
Open the file and render it in F12 and you will immediately see the artifact. You can check the raw and processed images by turning on/off the Switch node in the raw/fx frame.

Additional example.
I watched the introduction to Cryptomatte from Blender Developer.
And I saw connecting the Matte output of Cryptomatte to the factor of the Color FX Node instead of the Alpha Node.
I mocked this and created a new node tree.

However, Cryptomatte also seems to have limitations.
You tried to change the red petals to blue, but Cryptomatte doesn't mask the petals completely, so you can see the red color remaining on the border of the leaves.
(Please click on the image to see the edges of the blue petals at larger size.)
I tried a technique to adjust the mask area using the Dilate / Erode or Bilateral Blur and Colorramp nodes, but there were limitations.

After testing up to this point, I think there's an appropriate range for changing colors with Cryptomatte.
If excessive color changes are required, re-rendering the 3D data seems to be the correct way to do it.

I have to check if there is a workaround, but what you're trying to do seems generally problematic with mattes. This has also been previously reported on the bug tracker.

I was looking for a solution to this problem from the very first day since I have switched to Blender 4 years ago. I understand the benefits of Cryptomatte and different ways of usage. But I wanted just one easy pass with material ID with every render, which I can save to PNG and use in Photoshop. In the end, I have made my own addon. If it could help anybody, please enjoy it. https://blendermarket.com/products/cid


text:
Non-procedural tiles in blender
Good day everyone!
I've got 5 textures of a porcelain stoneware (tiles). Their size is quite big (60 cm x 119 cm), so it's not the usual small tiles. I tried experimenting with brick texture but I can't make it the right size, because the texture settings do not allow the control over the exact size of a brick, and I also got problems with applying the material to it. I also tried wooden floor addon, but again ran into problems applying the materials. Thought about making the tile texture of those 5 in photoshop, but it would be too repeated, and I want it to be more randomized. Of course I could make each tile individually and place them by hand, but it would not be efficient. Perhaps some gentlemen and ladies here could come up with an idea.
I want to place these 5 textures on and object as tiles and make them randomized, I'm making a bathroom. But can't understand how to make it good and efficient.
Thank you!

Hello, could you rephrase your post so your question is a little more clear ? Thanks :)

Hi. What's your question? How to make them seemless or how to map them onto an object? What's your goal?

Your question is hard to understand, if you want to make non repeatable tiles, you could use a porcelain texture and put your islands independently over the image in the UV Editor, scale them, rotate, etc

I'm sorry for my mistake, completely forgot to ask a question. c:
I want to place these 5 textures on and object as tiles and make them randomized, I'm making a bathroom. But can't understand how to make it good and efficient. Thank you.

No problem. Have a look into: https://blender.stackexchange.com/questions/15076/what-is-the-easiest-way-to-have-a-material-randomize-the-image-textures-it-uses (related or dupe)

Does this answer your question? What is the easiest way to have a material randomize the Image textures it uses?

Thank you!
But it doesn't quite solves the problem. Because the tiles do not fit on some walls in one piece, so i need to cut them somehow. I've put an image in the post.

you can use this node tree setup:

I made just 3 planes with 3 different materials.
Randomly i choose one of them in the geometry nodes setup.
result:

and of course, with every different seed, you get another result:

UPDATE:
just found out...it is even easier with collection:

other seed:

UPDATE:
I copied my result 3 times, moved them and added a cube.
To the one i added a boolean modifier and i got this:

blend file:

Thank you!
But the problem is that some tiles do not fit onto a wall as one piece and there's some small corners as well, so i need to cut them somehow. How do I make it work? I'll put an image to the post so it's easier to understand.

did you try the boolean modifier?

No, I did not.
So I make a plane using geometry nodes with those tiles, stick it onto the walls and use boolean on this plane?

i added my blend file so you can check it out

it doesn't care which object you take for the geometry nodes modifier because it will generate a new one from the grid.

Thank you!
Got it how to do this, last question is how can I control the gap between the tiles? To make it a little bit smaller.

Just change the sizex/sizey in the grid node


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How to rotate past 180 degrees with python?
I need to rotate an object along arbitrary axis (local Z) in the range of 360 degrees. However, the rotate_axis method limits the angle value to 180 degrees and adds a sign (+/-) to allow for 360 degrees rotation. So if I need to animate a rotation of an object by more than 180 degrees it behaves in an undesired way (Animation 1).
This is the code from first animation:
obj.rotation_euler.rotate_axis("Z", radians(40))
The second animation was made with manual input into rotation Z field.
What I'd like to achieve is shown in the second animation. I know it is sometimes difficult to come up with a solution without knowledge of what the end product should look like. The final effect is a cube that follows an animated path combined of multiple keyframes on a sphere. Like a car driving on the surface of the earth. (see below animations)

What I need to do is to rotate a cube (first picture below) so that its' local Z axis is aligned with a sphere normal (blue side up - second picture below), and its' local X axis is aligned with a line joining two visible plain axes (red side facing one of plains - third picture below). Now at the end ot this operations I need to have a 360 degrees data instead of +/-180 in order to avoid overrotation as shown in the first animation above.
Take a look at the animation at the end.

Here you can see what I am dealing with. When rotation around Z skips the 180 the cube is overrotating.

Possibly related: https://blender.stackexchange.com/a/215778/60486

What if the cube is at a place on the sphere, where the normal of the sphere (and so the Z axis of the cube) points where the X axis of the cube is supposed to point as well?  https://i.imgur.com/K8SwAB9.png

That is impossible. There are over 1000 cubes like this moving around the sphere using various paths. Moreover, the local X axis must always be perpendicular to normal, while the local Z must be always parallel to spheres’ normal.

Yes, it's impossible for a vector A to be parallel to a vector C and a vector B to be perpendicular to a vector A and parallel to a vector D if vectors C and D are parallel - because that would mean that vector B by being parallel to D is also parallel to vector C, and therefore parallel to vector A, and yet it's supposed to be perpendicular to vector A. So you need such a vector B that is both parallel and perpendicular to vector A.

try this:
import bpy
import math

scene = bpy.data.scenes["Scene"]
mycube = bpy.data.objects['Cube']
mycube.rotation_mode = 'XYZ'

scene.frame_start = 1
scene.frame_end = 100

mycube.rotation_euler = (0, 0, 0)
mycube.keyframe_insert('rotation_euler', index=2 ,frame=1)
mycube.location = (0,0,0)
mycube.keyframe_insert('location', index=1, frame = 1)

mycube.rotation_euler = (0, 0, math.radians(360))
mycube.keyframe_insert('rotation_euler', index=2 ,frame=100)
mycube.location = (0,-13,0)
mycube.keyframe_insert('location', index=1, frame = 100 )

result:
https://youtu.be/gpL9Hx3w-eA

Yes. I am aware of this. That was one of my dead-ends as I need to rotate along arbitrary axis parallel to sphere normal. So still I need to find the euler rotation  that I could pass to an object.

ok, then i don't understand what you want. maybe make a drawing what you want to have...

Have a look now.


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Can I Create a Linked Duplicate Consisting of Only Those Mesh Parts Defined by a Vertex Group Owned by the Duplicated Object?
I have made this mesh...

... and I have create two vertex groups. One for the whole mesh, called  "Start"...

... and another one which excludes a part of it, called "End".

How can I duplicate this object as linked, but make it look as it is with the second vertex group ("End"). Meaning, with the last part excluded. Is that possible?

You can "Duplicate Linked" the object with Alt+D.
Then, on the duplicate, add a Mask modifier, and select the Vertex Group you want to keep.
(You can also select the vertex group you want to hide, if you tick "Invert" (double arrow icon) next to the Vertex group field)

Very nice, thank you very much, I'll need this way too!!! But, is there any other way to do that, so as not to add extra vertices, edges, faces etc? Like when I just duplicate the object as linked.

If you duplicate As Linked (Alt+D), the mesh will be shared between the two objects so, no. If you do a simple duplicate (Shift+D), then you just need to delete the vertices you don't want.

Pity... It could be really useful if we could have one mesh and then duplicate it's vertex groups as linked without to add extra vertices, edges, faces etc to project!!! Is there any place-forum I can talk about it? As suggestion...

Well, the whole point of linked duplicate is to keep the exact same mesh, it's a design decision... Design can be discussed on RightClickSelect : https://blender.community/c/rightclickselect/

Thank you very much!!!

Also, it's worth knowing than a Linked Duplicate don't use more memory (BECAUSE it's the exact same mesh). So my answer is still quite efficient in term of memory usage and disk usage. However, it could be a little bit slower to display and render, because of the (small) extra calculations required by the modifier.

While this works, it's worth noting that linked duplicates don't respect lattice deformations. I don't know why. I imagine a lattice's tweaks do not reference the mesh data node directly. Whether this is a limitation or a strength of lattices I guess depends on one's perspective. But at the very least, one should be aware of this issue. Also, to be clear, i'm not criticizing the answer. I realize that this issue has nothing to do with the proposed solution. It would be just as evident in any other case of putting a lattice on a linked object, while not putting on its duplicate.

Also, lattices on linked objects cannot be applied. The option is grayed out. This is a curious outcome, and I've never seen anything like it elsewhere. It seems applying the lattice should work even in the case of linked duplicates, since there is only one mesh data node in use between the two objects. One wonders why there would be any kind of conflict that would prevent the applying of the modifier. Might be a bug.

Modifiers (including Lattices) are linked to the Object, not the Mesh. I understand that it is sometimes frustrating, and can seems unclear - but it's an intended behavior, not a bug. Anyway, the comments are not the place for this kind of extended discussion ;)


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When I render the smoke simulation, I get weird colors and skewing in some frames
I'm trying to render a nuclear explosion and it looks good in viewport. But when I render, some frames skews the smoke simulation, and sometimes it's just all orange.
I'm on 2.83.
Nvidia Geforce GTX 1060, Intel Xeon E5 2650 v3.
Here's some examples on how the frames look and the blend file. Frame 0133 is how it's supposed to look.
https://drive.google.com/drive/folders/1LUoLZ7tJmpXPBf-GAozhMXZquCEES8-9?usp=sharing

Is this with cycles or eevee?

Cycles. Eevee worked fine.


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How to create a hook modifier on every point of a curve using python
I made a script to add a hook modifier on every point of a curve using a for loop but I get an error in 2nd iteration.
Below is the code:
import bpy

curve = bpy.data.objects["Ellipse"]

bpy.ops.object.mode_set(mode = "EDIT")
bpy.ops.curve.select_all(action = "DESELECT")

for spline in curve.data.splines:
    for point in spline.bezier_points:
        point.select_control_point = True
        bpy.ops.object.hook_add_newob()
        bpy.ops.curve.select_all(action = "DESELECT")

Below is the error details I get in 2nd iteration
Error: Requires selected vertices or active vertex group
Traceback (most recent call last):
  File "\Text", line 11, in <module>
  File "C:\Program Files\Blender Foundation\Blender 2.83\2.83\scripts\modules\bpy\ops.py", line 201, in __call__
    ret = op_call(self.idname_py(), None, kw)
RuntimeError: Error: Requires selected vertices or active vertex group

From what I gather, it seem that the hook modifier is applied before even the point is selected. But I don't know how to resolve this. Any sort of help is much appreciated. Thanks in advance.

EDIT: in this answer hook is added to each vertex to animate a mesh using slightly different code:
How can I animate a vertex translation of a triangular mesh?
In short, this will work (tested on Blender 3.0):
import bpy

curve = bpy.context.active_object

# this can fail, check bpy.ops.object.mode_set.poll()
bpy.ops.object.mode_set(mode = "EDIT")
bpy.ops.curve.select_all(action = "DESELECT")

for spline in curve.data.splines:
    for point in spline.bezier_points:
        point.select_control_point = True
        point.select_left_handle = True
        point.select_right_handle = True

        bpy.ops.object.hook_add_newob()

        point.select_control_point = False
        point.select_left_handle = False
        point.select_right_handle = False

What you experienced is the essence why you in general should not use bpy.ops in scripts: the side effect of bpy.ops.object.hook_add_newob happens to be that new object is selected and the curve is deselected. I suppose it messes with execution of the operator bpy.ops.curve.select_all(action = "DESELECT") but I did not do extensive research.
To ilustrate the problem: add new curve, select one of points and execute in sripting:
>>> C.selected_objects
[bpy.data.objects['BezierCurve']]

>>> bpy.ops.object.hook_add_newob()
{'FINISHED'}

>>> C.active_object
bpy.data.objects['BezierCurve']

>>> C.selected_objects
[bpy.data.objects['Empty']]

In my opinion this is better but more complicated solution:
import bpy

curve = bpy.context.active_object

for spline in curve.data.splines:
    for i, point in enumerate(spline.bezier_points):
        m = curve.modifiers.new(name='scripted hook', type='HOOK')

        o = bpy.data.objects.new("empty", None )

        bpy.context.scene.collection.objects.link( o )

        m.center = point.co
        o.location = point.co + curve.location

        m.vertex_indices_set([i*3, i*3+1, i*3+2])  # left handle, point, right handle?
        bpy.context.evaluated_depsgraph_get() # magic spell
        m.object = o

If you omit the line with depsgraph evaluation, the hook modifier will activate too quickly and the vertex will be moved by object. I do not know why...

I have been fighting with bpy.ops forever now. half the time it works and half the time it doesn't. This saved me a ton of time from having to  change my whole approach thankyou.


text:
How Can I Rotate a Bone by More Than 360 Degrees?
I have downloaded a model from Sketchfab. It's a space ship.
This ship was not rigged, so I've tried to rig it myself. But I have a problem: I would like to rotate the rotors of the aircraft. So I tried to rotate the bone that I attached to the rotor, but I found out that when I try to rotate the bone it rotates only by 360°.
Can somebody tell me how I can rotate my rotor by any amount?

As Markus von Broady says, "It's impossible to go outside of 360 degrees range in quaternion".
So open the N panel, choose Euler instead of Quaternion and enter the value you want on the rotation axis you want.

Thank you very much. when I have change it to ZXY Euler it works fine

It's impossible to go outside of 360 degrees range in quaternions: "[...]rotation angles differing precisely by the natural period will be encoded into identical quaternions and recovered angles will be limited to { 0 , 2 π } (in radians)"  https://en.wikipedia.org/wiki/Quaternions_and_spatial_rotation

ok thanks for the precision, I'm going to edit my answer


text:
Blender 2.8 startup function working in addon
I want the addon search bar to be filled on startup:
import bpy
from bpy.app.handlers import persistent

@persistent
def addon_search(scene):
    bpy.data.window_managers["WinMan"].addon_search = "editor"

def register():
    bpy.app.handlers.load_post.append(addon_search)

This works but can I just check that this isn't looping or dangerous?
Do I need to remove the load_post handler after it has loaded?
Also why does it not work in an addon, it adds the handler but never runs.
bl_info = {
    "name": "Test",
    "author": "Test",
    "version": (1, 0),
    "blender": (2, 80, 0),
    "description": "Auto-fills addon search field",
    "category": "3D View"}

import bpy
from bpy.app.handlers import persistent

@persistent
def addon_search(scene):
    bpy.data.window_managers["WinMan"].addon_search = "editor"
    return None

def register():
    bpy.app.handlers.load_post.append(addon_search)

def unregister():
    bpy.app.handlers.load_post.remove(addon_search)

if __name__ == "__main__":
    register()

Ok figured it out, addons get loaded after the startup.blend is loaded, so load_post wouldn't work. Also in 2.8 scene_update_post has been replaced with depsgraph_update_post. (Which is much better imo) So i run the search and then delete the handler:
bl_info = {
    "name": "test",
    "author": "test",
    "version": (1, 0),
    "blender": (2, 80, 0),
    "description": "Auto-fills addon search field",
    "category": "3D View"}

import bpy
from bpy.app.handlers import persistent

@persistent
def addon_search(scene):
    bpy.data.window_managers["WinMan"].addon_search = "editor"
    bpy.app.handlers.depsgraph_update_post.remove(addon_search)

def register():
    bpy.app.handlers.depsgraph_update_post.append(addon_search)

def unregister():
    bpy.app.handlers.depsgraph_update_post.remove(addon_search)

if __name__ == "__main__":
    register()


text:
Why does an update function loop when string property is reset?
I have a string property, when it is updated it runs a function which runs an operator, the operator clears the string at the end to reset it. This makes the function (string_update) loop to infinite recursion. As I understand, order of events should be:
update string
run function once
run operator
finish
What am I missing?
import bpy

def string_update(self, context):
    bpy.ops.test.test()
    print("Ran")
    return None

class test_vars(bpy.types.PropertyGroup):
    test_update_string = bpy.props.StringProperty(
        name = "",
        default = "",
        update = string_update
        )

class Test_Op(bpy.types.Operator):
    """"""
    bl_idname = "test.test"
    bl_label = "test"

    def execute(self, context):
        bpy.context.scene.test_vars.test_update_string = ""

        return {'FINISHED'}

def register():
    bpy.utils.register_module(__name__)
    bpy.types.Scene.test_vars = bpy.props.PointerProperty(type = test_vars)

def unregister():
    bpy.utils.unregister_module(__name__)
    bpy.utils.unregister_class(test_vars)
    del bpy.types.Scene.test_vars

Every time you update the prop, it calls the update method.  Your update method calls an operator that updates the prop ... which calls the update method which calls the operator which calls the update method which calls the operator.....

In the execute method of the Test_Op class, you should access the property like this to prevent the update method from being called:
bpy.context.scene.test_vars["test_update_string"] = ""

That works perfectly thank you so much, would you mind explaining why this doesn't trigger the update?

@Way2Close The get set example emulates ("This is what the RNA would do internally") the way blender properties use custom properties as storage.


text:
How to register a property group in blender 2.8
Is there a way to add a property group to this method of registering, without adding a separate register/unregister function?
classes = (
    some_scene_variables
    some_operator,
)

register, unregister = bpy.utils.register_classes_factory(classes)

At the moment I am doing this, which works:
classes = (
    some_scene_variables,
    some_operator,
)

def register():
    for cls in classes:
        bpy.utils.register_class(cls)
    bpy.types.Scene.myvars = bpy.props.PointerProperty(type = some_scene_variables)

def unregister():
    for cls in classes:
        bpy.utils.unregister_class(cls)
    del bpy.types.Scene.myvars

But it seems wrong to change how I am registering just because I want to add a property group.
Thanks
Edit:
Something similar to this (just for illustration, I know this would in no way work):
classes = (
    some_scene_variables
    some_operator,
    bpy.types.Scene.myvars = bpy.props.PointerProperty(type = some_scene_variables),

)

register, unregister = bpy.utils.register_classes_factory(classes)

Can you clarify your question? Change from what to what? Inheriting from PropertyGroup should work with your code above: class some_scene_variables(bpy.types.PropertyGroup)...

@squarespiral The first code block shows what is described in the Blender 2.80 manual. register and unregister are generated using the register_classes_factory method. But since they are auto-generated, how would you add the PointerProperty to the scene now?

So you want to get rid of the lines starting with "bpy.types.Scene.myvars =" and "del bpy.types.Scene.myvars"?

Check the source
As with a lot of blender, can check the code for bpy.utils.register_classes_factory
def register_classes_factory(classes):
    """
    Utility function to create register and unregister functions
    which simply registers and unregisters a sequence of classes.
    """
    def register():
        from bpy.utils import register_class
        for cls in classes:
            register_class(cls)

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

    return register, unregister

As you can see it does no more than register unregister classes.  (Notice the reversing of list in unregister)
I would recommend using your own register methods. Even prior, would recommend own register methods over the now defunct bpy.utils.register_module()
To still use the factory, in conjunction with your own methods.
foo, bar = bpy.utils.register_classes_factory(classes)

def register():
    foo()
    # do other stuff

etc.  Or write your own factory that also takes type, property pairs.


text:
I need to run an operator after variables have been restored
I need to run an operator once an addon has been registered but at them moment if I do anything with "foo_number" it is at default rather than the saved version of it:
bl_info = {
    "name": "foo",
    "author": "",
    "version": (1, 0),
    "blender": (2, 79, 0),
    "description": "",
    "category": "3D View"}

import bpy
from bpy.app.handlers import persistent

class foo_variables(bpy.types.PropertyGroup):
    foo_number = bpy.props.IntProperty(
        name = "foo",
        default = 1
    )

class foo_update(bpy.types.Operator):
    bl_idname = "foo.foo_update"
    bl_label = "foo"
    bl_options = {'REGISTER'}

    def execute(self, context):
        print("some operation")
        # do something with foo number

        return {'FINISHED'}

@persistent
def update_op(scene):
    bpy.app.handlers.scene_update_pre.remove(update_op)
    bpy.ops.foo.foo_update()

def register():
    bpy.utils.register_class(foo_update)
    bpy.utils.register_class(foo_variables)
    bpy.types.Scene.foo_vars = bpy.props.PointerProperty(type = foo_variables)
    bpy.app.handlers.scene_update_pre.append(update_op)

def unregister():
    bpy.utils.unregister_class(foo_update)
    bpy.utils.unregister_class(foo_variables)
    del bpy.types.Scene.foo_variables

I now have this, but I cant find a way to remove the handler without it breaking:
@persistent
def update_op(scene):
    # bpy.app.handlers.scene_update_pre.remove(update_op)
    bpy.ops.foo.foo_update()

def register():
    bpy.utils.register_class(foo_update)
    bpy.utils.register_class(foo_variables)
    bpy.types.Scene.foo_vars = bpy.props.PointerProperty(type = foo_variables)
    bpy.app.handlers.load_post.append(update_prefix)

def unregister():
    bpy.utils.unregister_class(foo_update)
    bpy.utils.unregister_class(foo_variables)
    del bpy.types.Scene.foo_variables

if __name__ == "__main__":
    register()

Personally wouldn't mix handlers and operators like this. Why not do something directly with scene.foo_variables in the handler.  Also how are you re registering this to test? If unregister is called it will clear the variable.

I was just using an operator to test it was working in the right order, I have managed to get it working as I want, by registering bpy.app.handlers.load_post.append(update_prefix) and removing the handler.remove from the function, but now the problem is I am not removing the handler so it is still running? I added the new code to the post

Actually bpy.app.handlers.load_post only runs after a file is loaded, So I could probably just leave it like this without it doing any unnecessary loops? It will only run update_op if a new file is loaded?


text:
Blender system console character encoding
I'm using Blender on Korean Windows 10.
While studying Blender Python I opened the System Console to check for error messages.
By the way, some characters are displayed correctly in English and others are displayed as random characters that have no meaning.
As far as I know, it's probably an encoding issue.
But I don't know how to fix this.
Help...

I realized that the Translation option in the Interface tab of the User Preferences causes this problem.
I hope there is no interference between UI Translation and the Systeme Console.


text:
How to execute python inside blend file from command line
I'll explain the numbering of what I did.

I created a text file called lowRes inside the blend file as shown in the attached image.

And I noticed that when I click Run Script in Blender run with GUI, the resolution of all scenes is changed to 128x72.
Then undo by pressing Ctrl + Z, set it to 1920x1080 resolution, and save the file.
And I did the Command Line Rendering using the code below.

blender -b "my.blend" ^
-P lowRes.py ^
-S "scene 01" ^
-o "//output\##" -F PNG -f 3 ^
-S "scene 02" ^
-o "//output\##" -F PNG -f 5

good.
03.png and 05.png were generated as expected.
But the resolution is 1920x1080, not 128x72.
The python code doesn't seem to be running.
What am I doing wrong?

FWIW This works as expected for me.  The -P is for an external python script. If so: make sure your script is saved in same folder as CLI.  Passing a wrong name for script it fails silently and renders images with default size.  If the script is a text block in blend then   blender -b --python-text "lowRes"

@batFINGER amazing! That works for me!
--python-text was listed in the official manual but I haven't looked into it closely.
I have one last thing I want to know.
As far as I know, if you don't have a textblock or external python file, you can run python code with --python-expr.
But I failed to execute lowRes code using --python-expr.
I am using Notepad.
How can I write code that works correctly?

An example of using expression blender -b --python-expr "import bpy; print(bpy.data.scenes[:])"  Personally wouldn't do it. Would use the external script. (Save from notepad with a .py extension)

@batFINGER Am I misunderstanding expression?
I expected to include the code for scene.render.resolution_x and scene.render.resolution_y after --python-expr.
However, from the example you wrote, it seems that --python-expr doesn't work alone.

Not sure what you mean by working alone?  Have to somehow put the whole script into a single line expression.  Again: I  Wouldn't use that option.

@batFINGER Thank you for your time. I understood.


text:
How to Bake Texture Sequence in Cycles?
I would like to use EEVEE's Shader to RGB and Cycles's Fisheye Lnes Camera together.
To emulate Shader to RGB in Cycles, I want to render texture sequence of diffuse passes that respond to the lighting being animated in Cycles.
However, the bake function seems to handle only one frame.
Is there a good way to solve this problem?

You can try the add-on I wrote for this answer, recently updated for 2.8x: blender-image-bakery.py

@p2or
Thanks! I tested the add-on. It did a great job of animation baking, but it could only bake one object at a time. There are many objects and materials in my scene. It feels inefficient to join them as one object for baking. The blender's built-in bake feature supports multiple objects. Is there any way to process to bake animations and multiple objects at the same time?


text:
How to import text(scripted expression for driver) together when linking a character
I used the phrase bpy.app.driver_namespace to create a function for scripted expansion that can be used in the driver and it works well in the local character file.
However, when I try to bring my character through a link in another blend file, the text is missing text. To use the character, you had to manually link text to set the execution and registration options.
However, the latest characters in Blender cloud, such as Spring and Rain, automatically come in with text when link.
How do I achieve this?

https://blender.stackexchange.com/questions/194681/rigify-automatically-link-ui-text-file-in-2-8  (Same principle, assoc the text file to the model)

Thank you. The link was helpful.
When the following code is executed, text is associated with the object and the text moves together when you link the asset. bpy.data.objects['my_armature']['my_script.py'] = bpy.data.texts['my_script.py']


text:
Removing Weird Armor Textures/Objects on a Minecraft Model
I really want to remove the armor texture after downloading a template, but I can't figure out how to remove the armor object and the armor texture! Please help me!
If you want to check out the file itself, click here: Minecraft Blender Intro

Wondering what it looks like after rendering it, click here: [link] (https://www.youtube.com/watch?v=NYDOx_e1Zt8)

I am having trouble understanding the nature of your problem.  Is it that you cannot remove the armor, or do you not know how?

Please upload the .blend file so we can understand the construction of the model and textures.


text:
How Can I Easily Model Machine-Thread on a Cylinder?
I am modeling valve cap for my car radiator, but I am struggling with the lower part of it (thread). What would be the easiest method to shape this thread?

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

What have you tried as far? Can you edit the question and share some screenshots of your attempts so it's clearer what exactly it is that you are struggling with?  Adding a meaningful title would also increase your chances of getting good help.


text:
Jagged and pixelated edges from bezier taper on bezier bevel (Realistic lightning?)
I was trying to create a realistic lightning but if I use a taper bezier to curve the outer edges of the lightning bezier with a bevel, the edges get really pixelated and jagged. Also the mesh gets disconnected by the end. (See screenshot)
I was trying to put the lightning into another collection and another view layer, and then blur it in the compositor. But the layer with the lightning collection in it (its the only active one on that layer) is empty in the render layer node. But now I am thinking, "Is this even the proper way of fixing the issue?" All I want is for the taper to be not as jagged as it is.
What would be your solution for this?
All help is appreciated.
I included the current animated state of the lightning in my .blend file.

Blend file: Blend file Lightning


text:
How can I get the Total Face Area of multiple meshes?
In edit mode, there's an overlay option to measure the face area of selected meshes. The problem is when selecting multiple meshes you get the individual face areas for each mesh.
What I'm looking for is a way to sum all face areas to get the total face area.

I only find an overlay option called Face Area, under the Measurement section of the Overlay pulldown, while in Edit Mode, and it only seems to get the area of single faces. While multiple faces can be selected in Edit Mode, and the area for each shown, I see no way to get an added area even for the faces that make up a single mesh. The wording of your question suggests you were able to find a way to get the total area of the faces of a single mesh, but not a way to get the combined area of the faces from multiple meshes. Were you able to get the total area of a single mesh, and if so, how?

Total face area of selected meshes
Calculates the total global face area of all mesh objects selected.
Uses bmesh from object to get modifier deforms, and transforms using the world matrix to take into account scale.

import bpy
import bmesh
context = bpy.context
dg = context.evaluated_depsgraph_get()

bm = bmesh.new()
areas = []
for o in context.selected_objects:
    if o.type != 'MESH':
        continue
    bm.from_object(o, dg)
    bm.transform(o.matrix_world)
    area = sum(f.calc_area() for f in bm.faces)
    print(f"{o.name} faces: {len(bm.faces)} area: {area}")
    areas.append(area)
    bm.clear()

print(f"Total Area: {sum(areas)}")

Thanks! All I would add is that the numbers it gives are still Metric square meters, even if you change your scene Blender units. If you want Imperial square feet, simply multiply by 10.764. So print(f"Total Area: {sum(areas) * 10.764}")


text:
Curious to Know Official Names and Meanings of Various Properties (Custom, RNA , ID, etc.)
I sometimes find it difficult to recall what type of properties a Blender user or addon has, as well as what choices it brings. ("Set Driver", etc.)
I know there are clear differences between how to add new custom properties, but I'm still not clear on what the meaning is of things such as ID property, RNA property, or custom properties, when a Blender user referernces them (In forum or here).
Property A: We can add new property of obj, armature, or any IDdata,
obj['prop_a'] = 3.0 #(I added prop_a for current active obj)

https://docs.blender.org/api/blender_python_api_current/info_quickstart.html#custom-properties
In this document, it is called a "Custom property".
We can access this property by using a dictonary key. But we cannot access it by "obj.prop_a".
Then:
PropertyB: use bpy.props then add it for object
bpy.types.Object.prop_b = bpy.props.FloatProperty(name="Test Prob")
bpy.data.objects["Cube"].prop_b = 0.5

https://docs.blender.org/api/blender_python_api_current/bpy.props.html#module-bpy.props
In this document, the property is called a "custom property" also.
If it has no RNA_UI, then we cannot edit values such as min, max, etc. It is labelled as "API defined".
So what is the formal (or official) name, when we distinguish these properties for general use? And while hoping to find clear documentation which guides us about these distinctions and details to a greater extent (so that we can make a script)?
And I often see users make offhand reference to custom properties, ID properties, or RNA properties. But which is which? I'd really appreciate if someone could elaborate on this (or tell me a link which can guide me toward getting a better understanding of these things.)

Re custom properties   AFAIK would call any non API defined property custom... eg ob["foo"] or ob.foo. Not ob.location as that is already a member of bpy.types.Object   For want of a better name could call ob["foo"] an instance property, since it is (most likely) only defined on one object.  Whereas setting up ob.foo makes the property available to all objects of that type.

There are essentially three types of properties in Blender. It seems like their distinction has always been a bit murky.

built-in properties. These are defined in C code and exposed to Python through the RNA system. They could be called RNA properties, although I don't know if the term is typically used in that sense. These properties are always there and often have some restrictions in their usage. They can only be accessed as a Python attribute.
Registered ID properties. They are defined in Python code using bpy.props.*. Originally they could only be registered on ID types (datablocks such as Objects, Meshes, etc.), hence the name. Now, confusingly, there are some other types such as Bones, and Sequences, that can also hold ID properties. They can be accessed as a Python attribute. Using the subscript operator instead succeeds but gives you "bpy id prop" object instead of the value.
Custom ID properties. They are usually created through the user interface, but Python can also be used for that. Internally, these are also ID properties, so they can be created on the same datablocks and other types as registered ID properties. They can only be accessed by a subscript.

If you have a Python object, you can list the first two types of properties through obj.bl_rna.properties and distinguish them by obj.bl_rna.properties['name'].is_runtime. RNA_UI helps to distinguish between custom ID properties that have been created or edited through the UI and those that have been set by Python.


text:
Blender using too much memory?
I have a project with 4 objects in the scene. The total face count is 46,594. The viewport shading is set to Solid mode. Yet, my memory usage is at 15 GB. I've applied the multires modifier on 2 objects with the viewport level at 0. At 1, the memory usage goes up to 32 GB.
What am I doing wrong ?
My specs:
I7 3930k
32GB RAM
Gtx 980ti
File Link:
https://drive.google.com/file/d/1XmkH0xof6VzGU1cBndevUEKt3V8VWCoS/view?usp=share_link

Also I'm noticing that in edit mode, as I select faces of an object, the memory usage increases exponentially. Almost 1 GB per tiny face selected. Is this normal ?

Hey! Could you pack your Blend.file and upload it to https://blend-exchange.com/ please :)

The file is almost 1.2 GB. Can I upload such a big file ?

1.2GB is quiete large,  what exactly causes this large of a file if you only have 4 Objects with just 46k faces? You can try to make a copy file and strip everything that does not impact the lagging and upload it

Is it because I'm using 2-4 materials/textures on each object? Would you accept a Google drive link instead?

The memory usage is most likely due to using high res textures, try to use lower resolution while working on your file.

You can upload it to dropbox, googledrive or Wetransfer and ill try my best

Here's the file: https://ci3.googleusercontent.com/proxy/vHmGjk3ipgOdvL4NFHoq_evvaRSyFclPlSq-4vUNYZG-xyZ8ENVoSEBWMQbkiab0tJLDaZrFUl4kO9yA4RNTvjb1R3J6GmvUdnEcf6MMyeoXNeCokUMfzbSobtXRIXQ=s0-d-e1-ft#https://ssl.gstatic.com/docs/doclist/images/mediatype/icon_1_generic_x64.png

Hi. Please don't post essential information like links, file downloads or additional details in the comments section where it can be easily missed. Instead edit them into your original post with the [Edit] button above. Comments are transitory by nature, are hard to index or search for, and may be erased at any moment.

I can't download it sadly

Sorry for that. Once more :.    https://drive.google.com/file/d/1XmkH0xof6VzGU1cBndevUEKt3V8VWCoS/view?usp=share_link

How do you get a file to 1.2GB with 46k faces? Massive simulations? If it's only the Multires in Render Mode, delete it b4 upload. Also check if that reduces the RAM in VP.

I have no clue Frederik :) I've already uploaded the file ... Please check it out if you're free.

The google drive link is private. You need to change the access permissions to "link/public" (or so) so everyone that has the link can access the file.

Sorry again ! The link has been updated ...    https://drive.google.com/file/d/1XmkH0xof6VzGU1cBndevUEKt3V8VWCoS/view?usp=share_link

The file is really huge for the little meshes you have in there. I've extracted the textures. That's about 185 MB. So the remaining blend file is still 1 GB big. It looks like the two MultiRes modifiers eat 850 MB for breakfast. If the modifiers are applied (or removed) then the file size drops to 150 MB with 1.1 million vertices. I've expected something around 60-90 MB. Well, ok. But 850 MB doesn't look right, it looks like a memory leak or bug. Tested with Blender 3.4.0b. Maybe you can drop the file size if you apply new MultRes modifiers + "ShrinkWrap-copy" the original mesh.

Thanks ! I'll give it a try ... But can you confirm that it's a bug ?


text:
Tracked footage renders but not the 3D object
My 3d object doesn't render. Only the tracked footage appears when I try to render the scene. What could be the problem ?

Here's the .blend file.
https://drive.google.com/file/d/194iS-WFTLlGNtrLZ-7vMW65P0wfpIX3R/view?usp=sharing
Thanks in advance.

Got it ! However, I couldn't find a solution to my problem on the forum or elsewhere. So I thought uploading the actual file was the only way to know where I messed up. If someone comes up with a solution to my problem, I'll make sure to post the solution like you suggested. Thanks :)

https://blender.stackexchange.com/questions/53632/render-result-is-completely-blank See #4 also https://blender.stackexchange.com/questions/51179/blank-image-when-i-render and https://blender.stackexchange.com/questions/31243/black-screen-when-creating-movie

The problem is, in the Output Properties under Post Processing > Pipeline the Sequencer is enabled. This is by default and usually no problem when you create a 3D scene and want to render it, as long as there is nothing in the Sequencer.

But you have a strip with a movie clip there, so the Sequencer determines what the output shows - and there is no strip for the scene. The problem now is, you can press Shift+A > Add > Scene, but the only option available there is "New Scene", you cannot choose the active scene in which you are in.

To do this, you have to create a new scene with the New button next to the scene name. I would not copy the original scene but start with a completely new scene.

If you now go to Video Editing and try to add a scene strip, there appears the name of the other scene ("Scene") to choose it as input. This way you can have many different scenes where you create 3D contents and additionally have one scene only for the video editing. In your case you have to add the movie clip there as well of course.

If you just want to render your object to see how it looks and do not care for the movie clip, you can disable the Sequencer in the post processing pipeline while you render.
If you do not want to use the Sequencer from the Video Editing at all, you can go there, delete the strip containing the movie clip and since it's the only one, your scene will now be rendered normally. To get the movie clip in the background you can add it in the Compositor and use an Alpha Overlay node to composite the 3D scene above it.

Hey @Gordon Brinkmann could you copy paste this answer over to https://blender.stackexchange.com/questions/53632/render-result-is-completely-blank/ ? Feel free to ping me there for a free upvote

@DuarteFarrajotaRamos I did post it there now as well, but I saw the reason I give in my answer is already there, only that their solution to that is a bit simpler... just disabling the sequencer.

Yes, yours is a little more thorough, that is why i think it is a good addition. Thanks for posting!

It worked ! Thank you so much :)


text:
Is there a formula for processing a rendered area in compositor without affecting other areas?
In various scenes I have areas that could be isolated using cryptomatte or material id or view layer and I want to effect that area only. With colorramp, the result applies color to the entire output rather than the isolated area. On a case by case basis, I can fiddle with the result using color key, alpha over, mix etc. and get an acceptable result. But, what I really want is a way to do this simply every time.
I tried using holdout shaders and view layers. For example, from back to front is:

background
torus
plane
sphere

So, I created view layers:
Background collection:
background + torus holdout + plane holdout + sphere holdout
Torus collection:
Torus + plane holdout + sphere holdout
Plane collection:
Plane + sphere holdout
Sphere collection:
Sphere
But this didn't work. Combining them, in compositor with Mix blend mode, the result does not show the background behind semi-transparent areas of the sphere. Plane does not show the torus in transparent areas, etc.
It seems to me like such an obviously needed thing, that I'm hoping there is a formula to achieve this in compositor. Is there?

Please share your screens of setup or simplified file https://blend-exchange.com (given code paste into our Q via edit). Thank you

Thanks @vklidu I uploaded a blend file that shows one of the approaches I've tried to take. If you attach the "all" render layer to a viewer, you can see what the unaltered scene looks like.
The combination of other render layers, with colorramp muted shows roughly the view layers combined. Unmuted, colorramp affects the entire view.
My goal is to have a repeated method to mask areas and replace them with an altered rendition.

Sorry long day ... I'm not sure if I catch the point ... if your issue is lost alpha after Colorramp add Set Aplha node behind. Colorramp is black&white node only.

Thanks @vklidu That almost works. It fixes the issue with the colorramp extending outside of the render layer. But, the torus ends up with transparency where, in the "all" render layer it looks opaque (perhaps it's showing the background there).
My issue is not these specific things. I am hoping to find a general method of separating areas, processing them and composing them in compositor, similarly to how someone would use layers and transparency in photoshop/gimp.

Actually, I guess it's doing exactly what it should. So, I'll just call that the answer and try to learn how blend modes work.


text:
the texture is covering holes i created when exporting fbx
the texture ( color or picture ) is covering holes i created, please help
in the blender app everything showing correctly (in the Material Preview)
but when when viewing it in 3D viewer this problem occure

please show us more screenshots e.g. of your mesh or provide blend file

From the image, it looks like overlapping face

I think the problem in the export settings, because the texture showing correctly only when i export it as .glb