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How to better position a texture on sides?
Very often when I have to put a texture on something that is a cuboid, I always wonder how I should position the texture in the sides.
I wanted to create a wooden floor and what I did was to unwrap the mesh 1 using the option "project from view (bounds)", and as far I can see it doesn't look too fake 2. But is there a way to do better? How we should unwrap a mesh in order to look nice on the edges?
Thank you for the help

Hello :). The words look nice and improve aren't very specific. Please rephrase the question to be more focused. For opinion-based art critique try Blenderartists.org. :)

If it's a cubic shape like this, I personally don't bother using UVs (unless I have to export it somewhere else where nothing else works).
I instead use Generated texture coordinates, and I change the textures' projection from flat to box:

This way, the texture is projected from a box around the object, you can even use the "Blend" option to blend each face of the box so you don't see much seems:

Thank you seems much better! What if I have to export it in in Unity?

I think Unity has some ways to do that by itself. Otherwise, just use UVs, but maybe not like you did, I'd do something like these: https://i.imgur.com/j9ZNrnP.png   Don't forget to up vote and set this as your topic's answer in the top left corner.


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Change the colors in the Graph Editor
community this is my first question in the forum. Of course, I have been trying to find the answer for quite some time before posting, and nope, the setting I am looking for is not in the THEME tab from the settings menu in Blender.
By the way, I am using Blender 2.82a, and the problem is that I have a light blue color that interferes with the white letters in the graph editor's transform channels and it's hard to read(I have noticed most likely everyone has dark gray background), Please take look to the image.

In the view menu of the graph editor, uncheck "show group colors", and the default color should be back.
This light blue color you see is associated to the bone groups in the armature properties. It is very handy in the viewport, but make things less readable in the graph editor.

that was it. thank you so much, :) :) :) :)

Check Themes > Graph Editor > Channels Region. It controls the color behind the text.

Thank you. but that isn't the case, the channel region is set to dark gray and still, the graph editor is showing light blue, I already tried all of the colors in theme > graph editor tab "and all over the theme section" and it seems that the answer is not there.

This is rough, sorry.  I've been looking through this myself.  Is this a Blender preset theme?  Obviously this isn't the default color, so it's definitely something you can edit.  Maybe color pick that blue area, and then simply find that color, wherever it may be in the preferences.

Thanks @S. Magnusson, I haven't changed any of the color themes i have al default, and yes I did try a color picker and don't find that value anywhere in the theme section... I have noticed that it only happens when the object is a rigify armature or bone, here is an image. Thank you link... sorry just don't know how to add an image but the link is there, I tried many times  :(

source: Stack Exchange

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

sort: votes


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After Merging Duplicate Vertices, Sculpt Mode Model Drastically Effected

Ultimately, I am trying to subdivide my current model, but I can't until I clean it up. Subdividing without cleaning causes crazy protruding vertices everywhere.
Using Blender 2.8, I've begun the journey of cleaning my model by first removing duplicate vertices within the model. As soon as I do however, the model has crazy protruding lines as show above when in sculpt mode.
Solutions I've tried:

grabbing and smoothing the crazy protrusions for hours. it never seems to end up properly, not to mention, some of the lines seem to go into infinite space.
removing the faces in edit mode and then readding them. This is a terrible idea, it garbles up the model significantly.
Seeing if I can add vertices in edit mode to get rid of any triangles while maintaining other quads

I'm at the point where I wonder if I should just start from scratch again because I have no idea where I went wrong.
Note: I've added a link to my .blend file
EDIT: Re-uploaded my .blend file to the point before I merged my duplicate vertices

Welcome to Blender Stack Exchange!
See the edits below for an answer to this specific problem. Note that the eventual solution may not apply to all cases of this issue.
I have some bad news. This is a known issue with the Multiresolution modifier, and one that I have encountered many times. I think the next version of Blender is going to have a fix, but the test build I tried still has the problem.
The Multires modifier works (I think) by storing information about how the vertices it adds should be positioned relative to the ones that exist. When you change the ones that exist, it gets confused, and doesn't know where to put the vertices it generates, thus sending them off into infinity like you see. For this reason, it's best to not change the mesh once you've added a Multires Modifier. Specifically, merging and adding vertices that changes the flow of the mesh causes the most problems.
For your file, I tried deleting some sections and rebuilding them so that the modifier recalculates where the generated vertices should be placed, but couldn't get it perfect. In your case, it looks like restarting may be the best option. However, Blender has various backup files that may get you to a point before you changed the mesh. You can recover your last session, try an autosave, or check out the .blend1 or .blend2 backup files. There's questions about those on this site.
Going forward, it's best to not change the mesh when using the Multires modifier. If you have to, use the Apply Base button on the modifier before changing anything. This makes the mesh match the sculpt better, and reduces the chances of things going crazy. In your file, it was too late to try this, and that button made it go much worse. However, at least for right now, the Multires modifier limits your ability to change the mesh. Merging vertices or removing edges like you have will almost always mess it up.
For this specific instance:
For this specific case, there is a possible solution that avoids restarting. You can easily retopologize this model and clean everything up. It's a bit of work, but not bad at all.
Let's start by looking at the model in the file provided. I've circled areas where I immediately see problems.

Entering edit mode and removing doubles finds a bunch of duplicates, but causes the problems you're seeing. The top of the right leg also has a face inside the mesh that is causing issues.
So the original mesh is probably not salvageable while keeping the Multires, at least not easily.
What we can do is copy the mesh, get rid of the Multires, fix it up, and then Shrinkwrap it onto the sculpted one. This will give us proper geometry and fix all the issues.
To start, I copied the object, hid the original with H, deleted the Multires on the copy, and headed to edit mode. The first thing I did was delete half of the mesh, and add a mirror modifier with clipping enabled. I prefer this way over using the edit mode X-mirror option. This also allowed me to get rid of the face inside his right leg, as I removed the right side of the object. Then I removed doubles, and fixed any faces that weren't four sided faces (quads).
Which looks like this now:

Good geometry is important when modelling and sculpting, but takes some practice. It's always best to avoid triangles and ngons (faces with more than 4 vertices) as they do not subdivide well.
Next step is to show the original with Alt+H and delete the face inside the top of his right leg. This doesn't affect the Multires at all, but causes problems later on otherwise.
Back on the copied mesh, I added a Shrinkwrap modifier and set the original as the target. Make sure it's below the mirror modifier.
This will now stick the copied mesh onto the original. However, since the original is sculpted, the copied mesh doesn't follow the original very closely. This causes some issues with the Shrinkwrap, as it tries to find the closest point on mesh to snap to.
It's especially obvious on the feet, as it sticks to the top of the feet instead of the sides.

So back to edit mode on the copied mesh. Using proportional editing, enabled with O and using the scroll wheel to adjust the size, I moved the mesh around to follow the sculpt better. It doesn't have to be perfect.
Now the copied mesh looks like this:

At this point I also checked the mesh to look for any other issues. I did this by adding a Subdivision Surface modifier with the view set to 2. Any points with issues will show up as pinching or sharp points. I found an issue at the wrist, where there were some extra edges inside, so I deleted those. Then I got rid of the SubSurf modifier.
At this point, the mesh is clean. If the goal is only to fix the basemesh, you're done. Apply the modifiers, and make sure that the object is truly symmetrical, as the shrinkwrap often makes things asymmetric. I did this by just deleting half the mesh, setting the cursor at the center of the world and, setting it as the pivot point. Then I selected everything that should be in the exact center of the character and scaled it on the x axis to 0. Then I added and applied a mirror modifier to get the whole character again.
The modified .blend file with the fixed basemesh:
EDIT 2: Saving more detail:
Continuing with the edited basemesh created above, even more detail can be saved based on what you're next steps will be.
In order to keep this symmetrical, I'm going to start by deleting half the character again. This way I only have one half to worry about, and I can just mirror it again later.
I'll start by adding a SubSurf modifier again, and setting the view level to 3 like what you had before. Then I can add a Shrinkwrap again, with the original sculpt as the target.

Looking good.
It's not quite perfect, as the target for the shrinkwrap wasn't quite perfect, but it's nothing we can't handle.
From here, we can apply both the Subsurf and the Shrinkwrap, in that order. This will make all the vertices that the Subsurf generates real, and thus will make the mesh a lot denser in edit mode. This isn't ideal, but it could be worse. I would highly recommend making sure that your geometry is exactly like you want it to be before applying this modifier. Maybe even watch ahead in the video you're following to make sure you won't have to make any changes later on.
Once you're happy with the geometry and have applied the modifiers, we can get the whole character back. In edit mode, with the cursor at the world origin and set as the pivot point, Alt click the edge loop on the edge of the character and scale it to 0 on the x axis to snap everything in line with the exact center of the character.
Then we can add one final mirror modifier, and enable clipping again. There's a few issues in the mesh where it didn't snap properly, or where the original mesh was messed up to begin with. A few strokes with the smooth brush and a bit of repositioning with the Grab brush and it's looking good again.
You can apply the mirror modifier now, or keep it. If you're eventually going to use a Multires again you should apply it.
And that's it! Here's the final result:

The final file is included at the bottom of this answer as well. Feel free to use it, inspect it, or do with it as you please. From everything I've seen you should be good to go with the course!

Hi Brenticus, first, thank you so much for taking the time to help. I fortunately do have a copy of the project prior to merging vertices: https://drive.google.com/open?id=1guyUaC5mlULgItcxy5VagDTIE4Ujw3Fp - however I didn't find any active modifier on my model when in object mode (forgive me if I'm wrong, this is my first project). Is that copy of the project still too late?

Unfortunately I cannot open that file. The preferred place to upload blend files on this site is here: https://blend-exchange.giantcowfilms.com/. Then copy the link and add it to your question.

Thank you for educating me Brenticus, I've updated my main question link

I've added some edits that get the base mesh cleaned up. If you're interested in ways to keep the sculpted detail I can try some of those as well. Are you planning to animate this character?

Awesome steps and explanations! I really hope someone else can benefit from your post as well.
I do intend to animate this character and import it to Unity as part of a tutorial I'm doing on Udemy.

If the course uses displacement maps or has you apply the Multires then you may be able to save your work still. Let me know if that's the case and I can show you how. If you can link the tutorial you are following (if it's paid just link the page where you bought it from, I just need an overview) and I can see what the best option might be.

I found the course, and have an idea of the next steps. I'll update my answer soon with some steps that allow you to recover more detail.

https://www.udemy.com/course/create-game-characters-with-blender/ - The next section after the sculpting is the retopology. I do have a few more components I have to sculpt with a level 4 subdivision (like the eyes and face), but I am more than happy to try any alternate paths you may suggest. Although it may seem I'm only 6 hours into the course, I have probably spent more like 80hrs, constantly stopping the video and trying implement the same. That being said, any ways to keep work I've done so far would be a saving grace.

Edited the answer again, and got all the detail back! Only change at the end is that the vertices are real, and can be edited in edit mode. Makes the mesh a lot denser in edit mode, that's the only downside.

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


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A way to model spiky Groot head
I want to model the babygroot from guardians of the galaxy. Here is a picture it should look like.

My problem is now: how can I model the shape of the spikes on the head. I already tried some versions. In sculpting mode, it is very hard to achieve this, because I want that the spikes are flat on the inside and outside.When I try it looks like this:

It's not round and flat and the inside is not looking very clear.
Any idea how I can do this?

Could you show what techniques you have tried and why they failed? Maybe post some screenshots

You can start with cylinder, inset the top and extrude down to make a tube with bottom. You can then bevel the bottom exterior to round off the bottom part. Then use subsurf and edge crease to detail the top part. You could use curves with profile to make the roots and branches. If you find yourself lost with modeling task you should start with tutorials and simpler shapes to learn about methods so you can build your own approaches to modeling stuff, it's half the fun! :)

Quite a lot of ways. If box modeling - do what mentioned above, rough forms extruded / whatever in Edit mode, then refine with Subsurf / Multires. If dyntopo sculpting - you can change faloff of the sculpt brush actually in the Curve rollout.

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


text:
Find "Smoke" settings under Domain tab
I am following some basic tutorials of smoke simulations. And I always can't find the settings tab "smoke" under the smoke domain settings. I jumped through some tutorials to see if I am just using another blender version (2.92) but I always have the same problem. Also, the smoke sim looks a behaves different. It feels like they have different preset settings, but the most looks the same. I am also using mantaflow as everyone else. I am very new to smoke sims but have a good understanding of blender. I hope someone can explain. Thank you in advance
Here is a picture of the smoke sim of my desktop:
´
And here is an example of a tutorial file:

The option that you are looking for is now called GAS


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Joining objects glitch/bug/artifacts
I was modeling these flowers and I wanted to join the selected parts of each flower, so I can use them as a particle system. When I selected all parts and pressed Ctrl + j I get these strange artifacts. You can see them on the second flower in the picture. All modifiers are applied. I do not know what the Problem is.

Here is the blend-file:

maybe the last object selected (the active one) has a modifier?

It had. But I applied the subdivision and I still had the same problem.

could you share your file? https://blend-exchange.giantcowfilms.com/

sure

I do have the problem with all of them

it works fine here with 2.8 or 2.9  :/

Ok, interesting. I don't really have a graphicscard in my pc. Maybe blender just has problems to show it correctly. In renderedmode it looks fine. Thank you very much already!

What is the name of this particular part (shown as picture above) in your file? (many flowers... so)

I actually do have the problem with all flowers


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Tiller ploughing land. The tiller should leave marks on the sand materiel and while ploughing sand particles should emit from the tines of the tiller
I was able to create sand, however am unable to draw lines on it.I want to animate a tiller working on sand leaving lines on sand. Plse help with video

Use Dynamic Paint to produce a Displacement.

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


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Need help with displacement mapping please!
I got a new job in, and I need to make a design for 3D printing. It's for a growing pot, and everything is allright, but I have no idea why I can't make my displacement modifyer to work.
This is the reference photo:

Here you will fin the project uv-mapped and with the displacement pattern for the ingravings:
blender exchange file:

https://www.dropbox.com/s/c1meqh0khlvv0vm/8813-058_Hvidestenpotter_Ingraved.zip?dl=0
I would really like to know how to use the displacement mapping, as it would make future work a lot easier, I just can't find anything on the problem here :/
Kind Regards
Anders

Find (or create) a cross pattern texture, add it to the material and mix its influence to be 100% at the top and 0% in the bottom (e.g. with ColorRamp which will work like a gradient making the bottom part of the image of needed color) or mix that gradient into the texture itself

Related https://blender.stackexchange.com/questions/61785/modeling-waffle-shape-of-cone

I've added the blend-exchange .blend file now Ray :)

Mr Zak I'm not totally sure about what you mean. Can you try to explain your solution a bit more detailed :)

Anyone? Still need help :/..


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Zoom to one selection of many
I'm cleaning up meshes after boolean operations. There are lots of self-intersecting geometry and I need them all gone.

Some of the intersections are really tiny and hard to see. When I have all of them selected I want to deselect every "island" of selection but one. Zoom the view to that selection.
I can do it manually by hiding everything else. Select any edge and press L. Zoom extents.
But when I have 400 intersections I wish there was a more automated way of doing it. I can probably code it in python but if someone else already did it.


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How to speed up applying decimate modifier?
I have a dense mesh with uniform density. Each polygon is of about the same size. Details are varying, so I can reduce the mesh and still keep most of the shapes. So I add a decimate modifier.
When I set the level of decimation, it takes time as there is a lot of calculations. Sometimes minutes.
But when those calculations are done, I apply the modifier, it takes the same time again.
I am guessing that the first calculation is discarded and done again for some reason. Is there a way to work around it. I think it is this way for all modifiers but mainly noticed it for decimate (also booleans).


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Start Fluid simulation before frame 0
I want an object to emerge from the water. So I've created a domain and a water object in order to create my water.
When I begin the simulation it needs several frames for the water to settle down into the domain (edit: I could have simply made the Flow object a bit bigger than the Domain but anyway...), so I thought I should begin the calculation at frame -50 for example (Cache > Frame Start), so that the water has already settled down when the animation begins, but it doesn't change anything (!?!), the animation is exactly the same and it still takes several frames for the water to settle down.
What am I missing? Thanks. File here.

The Offset value you can enter in the Cache settings is just usable if you're loading a saved simulation cache and doesn't work for baking. Baking can only be calculated between positive Start and End frames. Before I simply retype everything that's in the manual, here is a screenshot:

ooh ok thanks  ;)  I'll put your answer as accepted

a bit tedious for the collision object animation though as you need to offset it then bring it back

Sure, but I'm afraid I can't change that :D

come on Gordon, please...  ^^

NO! (evil laughter) :D sorry for being off-topic

actually it looks like if the Flow is a bigger than the Domain it works as well, so I don't have to wait for the water to settle down

I'm sorry, actually that's what I usually do - I didn't think of pointing that out because I was too focused on the offset topic.

no problem, it was useful to know anyway


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how to fix this fluid simulation
It's my first post in here, so I hope a friendly soul wanna help me.
I got this problem with my fluid inside of my obstacle. I want to "flood" my pumpkin head from inside out, to force the "honey"-fluid to come out from the mouth or so..
you can find my project here:

It seems like though, that the obstacle has an "invisible" "fill" or "wall" inside of it...

I have already tried to adjust different things on my fluid simulator, but, nothing seems to work out for me. I'm new to blender, changed from maya, so maybe it's just a stupid mistake I have overlooked.
I hope you can help me :)
Kind Regards
A

Hi, welcome. This could depend on the mesh object, probably. Usually with fluid interactions many factors can give weird results. Check obstacle object mesh for usual things, like unapplied scale, normals, double geometry, etc. I suspect this would be hard to solve without having your file. If you wish so, you can share it on http://blend-exchange.giantcowfilms.com/ then edit your question and paste the provided link.

Hi m.ardito!
Thank you so much for your answer, I have postet the link for the project now! :) I maybe have an idea about the problem could be something with the mesh, after deleting faces and adding the solidifyer.. I don't know if that can cause some problems.. as you say, The problem is the mesh of the obstical. The fluid runs perfect out of the mesh..

I tried your file, and noticed the "obstacle" (which has unapplied scale, as the domain and fluid too) was really a high detail mesh... but had 2 "geometry creating" modifiers not applied:

a solidify to give depth to your pumpkin shape
a catmull clark subsurf (level 4!) to smooth it out

that gives over half million polygons...
(note I uploaded - valid - images but atm I they don't show up... I guess imgur.com has issues... I'll fix this later if still needed. edit: now they seem ok.)

in order to check the mesh as the simulation could see it, I initially applied the solidify modifier, and inspected the resulting shape with the 3d print toolbox tools ("check all") which gave a lot of issues, and you can easily see that your solidified shape has many badly topologized surfaces (due to the modifier).

It does not seem that bad, at first glance, but since you later add a c/c subsurf (level 4) to this, the bad surface just becomes more smooth and detailed, but if you disable the c/c subsurf modifier, it is easy to spot several part of the mesh that have that bad topology

this kind of (resulting) mesh issues can easily give bad fluid sim results, imho. I would try to

remove the subsurf
fix topology after applying solidify
test the fluid sim with this simplified and fixed mesh

and/or practice with a much simpler obstacle mesh (think of a basic cube with a simple square hole), to be sure the simulation is correctly working with that, and only then, replace the obstacle with something more complex (but with good topology).

Thank you so much dude! I went in to fix the small awkward faces and verticese (spells?), so the model was much simpler. Then I removed the top of the mesh, and made a "stock" or what it's called in english? from the buttom, and then added it to the top of the mesh, so the top was only one face instead of 400 million.
Wasn't really thinking about it, but now I will make sure all my future models evoid being complex builded! what can you say.. you learn something new everyday :P
Thanks again!
Best regards


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Exported Uv maps have no color (Fixed)
Whenever I export Uv maps from blender and open them in any program like unity and gimp, they miss all color and only have the basic Uv outlines for the object, anyone know what I am doing wrong?

UVMaps are meant to export UV layouts not color information, what you want is to export textures

I think you are using Export UV Layout function - this just exports an image containing a wire so you know where to paint the texture.
If you already have the texture and just want to save it, open it in UV/Image Editor and press F3.


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(Fixed) Knife project removes vertex points but leaves faces untouched
So I am trying to make a hole for my barrel but whenever I use the knife the faces I selected stay but the vertex points get removed, not sure what causes this and restarting blender didn't fix it.

Here is the file

can you share the blend file? maybe something wrong with model...

as far as I can see, you have some modelling issues. You were modelling with modifiers activated. Also, the interior of the gun is a different object. You have to merge/join those objects then perform the knife project. To join models select the desired objects, and press ctrl+j.

Thanks so much for pointing that out, not sure what I did to create 2 of the same objects but that was the problem, cheers

remember that modifiers/editions/etc will work on a object at a time, that's why join meshes might be what you need


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I'm doing something wrong while trying to PARENT an object together
I'm doing something wrong while trying to PARENT an object together.
I'm not sure I'm following the steps correctly.
Note the "dotted" string seems still attached to between the Icing & Donut still after "parenting".
Hope someone can solve this problem.
Thanks hugely and regards in advance.
Mike

Hi. After reading your question, I'm still not sure what the problem is? You say you keep "making a mistake". What mistake? What isn't working with the parenting? Please add any additional details you can by using the [edit] link below the question. Thanks.

Please add meaningful headlines. Blender StackExchange (and StackExchange in general) is a Q&A site and nobody finds your question and resulting answers under "Frustration with making the same mistake". You can edit your question by clicking on the edit link below it.

Apply transformations to both the objects
Select the child object then the parent object, ctrl+p ("keep transform" - this maintains distance between objects)

I have selected keep transform. When I then grab G the object and move it away ts still detached (as in attached imame)?

Try to apply transformations before you parent them, apply (location, rotation, scale) by clicking ctrl +A, make sure scale is not uneven.


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How to make objects in a video glow?
Regarding my previous question, how to remove background, I wish to do the following:
There will be a narration so I will need each object to glow while I talk about them, how can you do this? Please demonstrate on one (or more) of the videos.
Thanks in advance
EDIT
I would like the object to emit light, affecting the other objects.

Could you be more specific about what you mean by "glow"? Do you want these objects to appear brighter or should they emit light that affects the environment or do you want something like a fuzzy glowing outline? A single still image would help.

Please add some more details to the question, it is not exactly clear what you are asking. Try not to reference other posts too much when asking and instead try to create a unique, self-contained question.

You might be interested in this ideo tutorial: http://www.blendernerd.com/five-ways-to-create-glow/

@iKlsR I know but gandalf3 told me not to put two question in one question so I had no choice but to do this.

@Fweeb look at the edited question. Thanks :)

You are asking for a tutorial. Instead of giving you the tutorial (this is not a place to demonstrate a whole tutorial) I am going to show you a workflow. Now you can google each of these topics.

Import movie into blender.
Render out as separate images (for convenience).
Place a grey plane in front of the camera.
Shine a spotlight on it where the object you want to glow is.
Insert keyframes and move the light. The light will get animated. Seeing the images from the video in the background helps.
Use the compositor in blender to render out a new movie. The grey plane should be multiplied with the images you rendered out earlier.


text:
How to move render to the left for space for text?
Currently, I have this:

However, I need space!:!
As you can see above, I need space to write text on the right, while keeping the background gradient.
I had a look here: How can I resize/move the "canvas" of an image in the compositor?
But it doesn't seem to work.
This is an example of my current compositing:

.blend file: http://www.filedropper.com/xtruder22_1
Many Thanks

You could either do that in post processing (i.e. GIMP) or you could simply make the camera bigger and position the image to the left.

I'll see if there are any other answers.

@CharlesL Thanks loads, but I'll stick to the answer ;)

You can use the Transform node, for example:

Wait, did you make a text object in blender or did you edit the image? Thanks :)

@TimTimmy The text part was captured from yur quesion. :P you can either make it on the BG image. or put it in a separate render layer (or scene), then use another set of Transform and Mix (or Alpha Over) node to composite further (Another Transform node may be needed, too).


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Mirroring Blender 3.0 is not doing what I want it to do? How to get them into the right place?
I want to get the bed legs from the left to be mirrored to the right.
Whenever I try the legs don't get on the right spot

Whenever I add a mirror modifier and click Y then they are in the middel of the bed.
I first thoughted the red X was not in the middle, moved the whole screen so the red X is in the middle but after then I want to mirror it just gets in te wrong spot. Is it remembering still the red X axe? I also read before I post this to move the origin, the little orange dot, but don't know how to move or where to move to, one I found said make an empty,, post was from 2016 and shift A wasn't doing anymore what I read in that post
I am just started with blender (some days) and not much experience with drawings, the youtube video I found, was too fast for me to follow and missing some information for a beginner.

In advance thanks for your answer
All the best
Esa69

Thx. I have understood following:  empty = just create a (shift a) plane and name it empty1, move (g) the empty1 to the middle of the bed, then add modifier mirror on the Y axis and it works indeed, Placed a picture 4 after your answers to explain for others.

Ps: Shift a is the shortcut key for adding any object into the scene. It should still work in 3.0.

Don't have time to write a full answer, but IIRC the mirror modifier works off the object's origin...

dunnowhattocallmyself thx for your answer, At the time I read it first time (before I posted this) I could not find empty in the menu. because of your answer I understood, maybe make your own and just call it empty. Is there a better way to make emptys?

thx Ron Jensen, dont know what you mean, Googled IIRC and found here and there but dont knwo the meaning of it. What I did wrong I thinking now, is that the bed was not exact in the middel of the X axis, therefor mirror worked but not to the end of the bed but in the middel. But didnot know how to reset it without starting all over. The empty solution did work, not so nicely done if I wanted, but I am not expecting after few days of playing with blender to do all perfectly, but I got the idea how to solve this, thx for your help

I also had problems with the mirror modifier in the beginning.
The most logic way to use it: just use an empty as mirror object. This should be placed where the origin is in your upper picture.
If you then use the mirror modifier:

it should work.
Explanation how the mirror modifier works without mirror object:
The object mirrors itself at its own origin point. This is very easy to understand, if you add a mirror modifier and move the object in edit mode:

Thx. I have understood following:

Thx. I have understood following:  empty = just create shift a plane and name it empty1, move (g) the empty1 to the middle of the bed, then add modifier mirror on the Y axis and it works indeed, Placed a photo to explain

When I made a plane, moved it too middle of bed, you still can see the plane, so I did a move down out of sight, is there a way to make an empty which is better then my plane and move it out of sight? btw If I delete the plane then it also deletes the mirror Y axis so I couldnot delete the empty1 plane I used

You don't need to use a Plane! To add an Empty to the scene, use SHIFT-A and the Empty items are around halfway down the main menu with a 'Y' shaped icon, not on the Mesh submenu. You want the Plain Axis Empty type.

Woowww  Thx John, thats the first thing I missed, didnot see that empty in the middel, thanks mate,

@ESA69: maybe you should read the answer text more carefully next time. I wrote: "just use an empty". And in the first picture you can clearly see in "mirror object": Empty

and it would be nice, if you could click on the checkmark left of my answer, if it helped you.

@Chris Didnt see the checkmark ,
John Eason solved it for me as I didnt know whats an empty , I am like one week new with blender, so all is new for me. Didnt see checkmark for
John Eason to use

Hi Chris , I don't agree, it wasn't clear for me what you ment, I am sorry for that and yes I did read your email several times, maybe I am too stupid, but I don't know where to find empty until John Eason said to look in the menu and search for empty see above and then with all comments I couldn't figure out where the empty was, I google always before asking, but finding or missing the point about the things I cant find or think about I use to ask the community, thank for your  friendly answer and your help is much appreciated. I wish you a wonderful day.

@Chris, Do I need to close this case somehow? For me me problem has been solved, I also documented as much possible for others to learn from my question

As I wrote: if my answer helped you, just check the checkmark left to my answer. But you don’t have to do that. Then it is not „closed“, but other can see that the answer works and helped you to do it. You can also write your own answer and check your own answer as right.


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Environment choice for a color-only objects
My question will definitely sound incredibly noobish, but I started to play with 3D graphics and Blender just a few days ago (after a month-lasting struggle with OpenGL basics) and I've run into trouble.
I have "created" a nice small bunch of models for a 3D game, determined that I wouldn't use a single texture for the appearence of the objects. This is what they look like:

Right now I'm trying to create some environment (terrain, lights...), but all of my previous attempts have failed.

I tried to create a hill without modifying it´s color. Result: the hill is unrecognizable, it has just the same color as everything else.

I played with Z-transparency. Result: better, but nothing delighting.

Instead of trying and experiencing failure again, I want to ask: is there any way I could create (a visible) terrain consisting of hills and valleys without using textures? Are there any specific ways of doing things when doing "cartoon graphics"?

You need to use better lighting. If you have shadows and such, you will see the form better.

Thank you... Well, I'm a beginner. What does better lighting include? Right now I'm using point lights from several sides of the scene. Do I need to add something special for better shadows?

Use a sun as main light to get better shadows. A sun is a "all scene" light that has parallel rays from anywhere. Just give it an angle (try 45° to see) and your whole scene has shadows. Add some other types to make things look better here or there.

reduce sun's size (properties) to get sharper shadows.

Wow, thank you. Just one more question: if I want "hills" on an adjusted plane to drop shadows, is there something special I've got to do?

enable Ambient occlusion to get better lighting " you should lower the light source intensity "
move the light source to get the shadows where you want
use proportional editing to create hills
add decimate modifier to get the LOW POLY look

This doesn't really answer the question


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Animated procedural stylized water ripple in Cycles material
I'm trying to find out how to create a procedural material that creates an animated diffuse ripple around any intersection or 'edge'.
e.g. cube lands on water surface, edge of water touching the side of a pot, etc.
On the top right of the picture below is a quick breakdown of a few of the elements.

A thick inner 'ring' ripple that wraps around the cube.
A thinner outer ring.
The foam at the edge of the water.

I'm not a math wizard, so I kinda followed a thread and got this node setup:

I hope I understood and got the description for the nodes right. Here's the result:

A few problems come up here.

Is there a way to 'distort' the circle into a wavy ripple around the cube as shown in the breakdown?
The ripples don't follow the shape of the cube since it's
calculating from the origin point.

For problem #1, I'm thinking of using #noise.random() to generate random values which then goes into a sine math node but I have no idea how to make it only affect the edge of the circle.
For problem #2, I believe that I'll have to start over and use a different approach but before I do that, I'm hoping that there's someone here that knows where to go from here.
I did try to tinker with dynamic paint but it doesn't work with fluid sim. It outputs an error saying no UV data is found.
I don't want to ask too much, so if there's a solution just for making the circle 'distort' around the cube over time, that would be good enough. Thanks in advanced.
Cheers.

Here is the thread that I mentioned in the post: https://blender.stackexchange.com/questions/26388/can-i-refer-to-another-objects-properties-from-a-cycles-node-shader-drivers-i

I don't think there is any way to achieve #2, at least not automatically. You can't access shape information, or geometry intersections from inside Cycles shaders as far as I know. You would have to manually define a "square shaped ripple". Have you looked into Dynamic Paint feature? Not sure if it is an option for you, but may greatly simplify your workflow.

Can you post a .blend file?

@DuarteFarrajotaRamos Since you suggested it, I looked deeper into the features and oo la la it can actually paint vertex weight. It solves problem #2 elegantly. I'll update the post about it later.

@ScottMilner Sure. Thanks for the link! I was looking for a place to upload the .blend file. Links to it should be in the post now. You have to bake the fluid sim yourself if you want to test it with the fluid animation but it shouldn't take long at that resolution.

You should post your findings as answers below with a short explanation of how to achieve it and why it works or not.

Distorting The Circle
I did some more experimenting and I got like a 50% success in distorting the circle.
I added 2 cross product nodes and 1 normalize node to screw around with the x y z values before plugging it into the multiply nodes which are now in the 'circles' node group.
The theory: The 'circle' node group draws an infinite amount of n unit lines from the origin of the cube, creating a sphere with a radius of n units. Where the sphere intersects the fluid, a circle of diffuse material appears on the fluid.
To achieve the distortion, a relative IRL suggests that I randomize the radius of the sphere by jumbling up the x y z location data of the cube. It should be able to mess up the radius enough to make a wavy looking circle. I used cross product because it was the one that came close to the desired result.
I wish I could explain this better, but then again, I'm no math wiz.

It looks close but when I render out the animation...

I got electricity instead. Coooooooooool but still not what my project team needs.
Aside from how it looks like electricity, it still doesn't hug around the cube as much as it should and there's very limited controls on how much it spreads out.
Trying Out Dynamic Paint
I never considered trying out the vertex format but as suggested, I looked deeper into what it does and it works like a charm for problem #2. The setup is shown below.

The node setup doesn't look like a nightmare anymore. Thanks, Duarte!
This is still an incomplete answer. I might update this answer as I find out more stuff. Feel free to add on top of this or come up with a better solution altogether.
What's Next: How to make the distortion behave properly (or find something else that behaves properly) and hopefully, apply that on top of the dynamic paint.
.blend file with the electric ripple thing:

.blend file with dynamic paint:


text:
Armature Deform with sharp limits
I have a requirement to rotate part of an object, leaving other area intact, so have created a bone and defined the vertices belonging to the bone. Since the part to be rotated is very sharply delineated I am using manual vertex assignment. However, when the the part is deformed some portion of another part of the object is also getting deformed, which is not desired. I tried setting the paints in the weight paint mode, but here also the brush either includes the unwanted portion or subtracts from the part itself.
A related query is: I have seen highlighted lines extending from vertices to neighboring vertices, that seem to be indicating weights (or influences? not sure...  I am new to blender). What's the logic of applying these weights and is there a way to change them? They are sometimes seemingly arbitrary. In the attached figure for example, A influences B and F but not C. Why? And how, if at all, to change this influencing?

For "mechanical" models that do not deform each piece, you could even avoid weighting altogether, separate the pieces into their own objects and parent each piece directly to its parent bone.

Yes, eventually that's what I may have to do.

I found a workaround:
1) In edit mode, select the vertex group assigned to the bone and hit P to separate the selection from the main object
2) remove the vertices from the main object that belong to the bone (there's actually just one in this case)
3) In object mode select the main object and the separated one and hit ctrl-J in order to join them. Now if I select the vertex at the tip of the part to be moved, there is no influence shown to the main part vertices. Maybe there is a double vertex at that position, but that doesn't create any problem for me for now.

Interesting! I don't know why that works, but I'm glad it does. (:

yeah :) Maybe, I'm doing too many wrong things, which cancel each other and in the end there's left something that is close to the right :))

You don't actually need to use Weight Paint to change the bone influence. Try this:

Find the vertex group you've been modifying in the Mesh tab of the Properties panel. (It'll probably be named after the bone.)
Select all the vertices and hit Remove.
Select only the ones you want the bone to move, and hit Assign.

You can see which groups the active vertex belongs to in the N panel, under Vertex Weights, and can edit them manually if necessary.

Whoops, hit the post button by accident. More coming...

Actually, I am not using automatic weights but defining vertex group of the bone manually as shown in the first diagram (the highlighted vertices were added manually to the bone vertex group). The more interesting problem though, is the one related to default assignment of influences. How is it determined? It is certainly not based just on the distance between the vertices as can be seen clearly in diagram 3.

Hm. Well, if you're doing manual assignment, it should work. I wonder what's going wrong. I think the default assignment is based on the distance from the bone--you can switch your bone view to Envelope to see this.

Are there any other vertices in that vertex group, and are those selected vertices part of any other groups?

No, there are no other vertices in the group. I have double-checked that. I also removed the double vertices. Thanks for your responses btw. I found a work-around that I am describing below.


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How to force copy location of a vertex to modified object?
I have two objects, out of which:

one (d1) is making rotation and translation.
The other object (d2) has curve modifier applied to it.

The requirement is: d2 should copy the location of d1 (actually, an empty that d1 is parented to) during motion, with vertices A and B sticking together all along.
But, since there is a curve modifier on d2, vertex B get shifted to a lower position and the copy constraint uses the unmodified location of B for the location copying resulting in a gap between the two vertices.
Is there a way to force vertex B of the object d2 to stick to vertex A of d1 regardless of the modifiers on either objects?
I also tried parenting an empty (e1) to the vertex and creating another empty (e2) at the modified location for d2 to copy the location of, but that didn't help.
Here are the steps to reproduce the problem:

Open the attached blend file
Go to the time-line view at the bottom and move the pointer to zero frame position. The objects (page_0...page_5) on the right hand side are all straight (i.e. unbent) and stacked on top of each other. Each page is parented to a rotation axis and has a curve modifier applied to it.
As you move the pointer to frame 13 the top object (page_0) rotates to the left side, the shape-key on the curve makes the page to bend, page_1 parent empty copies the location of the page_0 empty during this motion, so two top objects are stuck together
Now if you continue moving the pointer to frame # 25, page_1 undergoes rotation as well as translation, it shifts to left side, page_0 also rotates by a few positive degrees so that the two pages are aligned in their angle. Page_2 parent empty copies the location of page_1 empty during this time so these two pages are together.
The requirement is just as the right hand side page is stuck to the turning page, the left hand one should also have the same location so there is no gap between the pages during the rotation. But as you can see in the animation, this is not happening because of the curve modified bending the vertex that's supposed to be copying the location of the turning object.

Hi, since this could be particularly bound to how you specifically set up your contraints, modifiers, I suggest you to share the file (use http://blend-exchange.giantcowfilms.com/ to upload the file, then paste the provided link in your question's text), to make finding a solution easier.

Sure. Here's the link:. Please have a look at the first 3 left hand side objects at the time of rotation.

ok, I pasted your link in the question text, but in the file objects seem to be named differently, not d1/d2, e1/e2... please edit your question and add some reproduction step...

Appreciate your help. I've added the reproduction steps.


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Workflow to model and texture a jigsaw puzzle
Goal
Create a repeatable workflow to model and texture different 500-5000+ piece jigsaw puzzles for use in Tabletop Simulator.
Question
How would you model and texture a 500-5000+ piece jigsaw puzzle from a vector cut template appropriate for import into Tabletop Simulator / Unity.
I'm familiar with Generating jigsaw pieces from svg curves but think he quits just when it gets interesting.  Looking to move beyond 2d.  This is a complete, albeit small, puzzle cut template:

Edit: I removed my incomplete/attempted solution to reduce this to a single question.  Hope this is better.

Is this actually a question? What are you trying to ask here? Please limit it to one specific question. If you have multiple questions, please post each separately.

No, it's not a single question.  It's a broad request for help; I'm clearly lost.  I believe the goal is clear.  Is there a better place to post this?

Broad questions are not appreciated here. Related: https://blender.stackexchange.com/questions/59086/generating-jigsaw-pieces-from-svg-curves

Thank you for linking that.  I didn't have enough reputation to do it myself.  It was my hope that this picks up where you left off.

You can post this on blenderartist.org (i think).

The question would be more clear and specific if you [edit] it with screenshots of example vector templates, objects you created etc. If any part of the linked answer isn't clear you should point out more concretely what exactly, show the steps you've done and the step you're stuck on

I had as many links and attachments in the original question that I could (two, thanks stack exchange).  I removed them because they were part of my incomplete solution.  Which I'd gladly post again as an answer (though probably completely misguided; I came here for help), but stack exchange won't let me.  Can't include them because it's too broad.  Shouldn't remove them because it provides context for the question.  Argh.

"How would one go about projecting an image across all these individual piece objects? That then get baked into textures? That can then be applied in TTS?"
I would just use the single image as the texture, and each piece would start out being in the same object mesh so that they can all be unwrapped from view at the same time and carry the same material - then you can separate each separate piece with P - 'separate by loose parts'. No baking needed.
Incidentally, I advise you to increase the resolution of your curve object before converting to mesh if you are concerned about the edges of each piece.

I had been reluctant to join the meshes only to separate them later.  I worried that it might be a lossy/approximate operation.  Once they're in the same mesh, you just UV unwrap the mesh, apply the image as a texture, then separate again?

Yes, I suggest trying it on a simpler project as a proof of concept first so that you make sure it will work for you. Join, uv project, and then separate.

This doesn't seem to be doing what I want/expect.  If I open  extrudedpuzzlecutascurves.blend, box select the curves, convert to mesh, join, separate by loose parts, I go from 54 objects to 162.  That's without even trying to texture anything.


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Geometry nodes: unable to use "reflect" vector math tool
Perhaps I'm not that far from succeeding, but I can't figure out how to properly use the reflect option provided by the vector math node.
I want to mimic the way light paths reflect against a parabolic mirror, thus materialize the way its focal point distorts when rays come at a certain incident angle. The following allows me to create what I would call the incoming rays field (i.e. parallel rays coming from the sun in my scene). Then I was expecting to mix this vector with the normal vector of each face in order to indicate the direction of the reflected ray. I fear I'm not very clear. Here's the node setup

Could anyone give me a little push to solve this?
Thank you,
Vincent.
Edit: Something quite closer to the solution, but my rays point outwards, it's quite puzzling for a reflection, isn't it? I fear I am missing something crucial with Euler-to-vector transforms.

Sorry for the noise, I solved my issue simply by applying a vector math Scale set to -1 to my output vector (before Align Euler to vector node). It works the way I wished.
Thanks for reading!
V.


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Grease pencil line art is missing edges
I want to outline the edges of the following chip object using a grease pencil line art modifier. However, it only outlines some of the edges: only the ones forming the silhouette of the object. The other edges are missed, even though their angles (90° and 135°) are well within the set threshold. I added a cube to show that similar edges are outlined there. Any idea what could be going wrong?

Here's the .blend file, in case that helps.

For some reason, your chip object isn't affected by Line Art modifier > Edge Types > Crease Threshold. I'm unable to find why. Any idea what operation/modification you may have done on the chip object ?

@Lutzi I created it by importing the shape from a .dxf file, converting that to a mesh and then extruding. Maybe that has something to do with it? I would have thought that the final mesh should be identical to one created by other means..

Correct normals
Some of your normals are pointing inwards. First select your chip object, go to Edit Mode, A to select all, Alt+N > Recalculate outside.
Disable auto-smooth
Still with the chip object selected, disable Auto-smooth

Tweak grease pencil
Select your grease pencil object. Then you can tweak the Crease Threshold. If you go all the way to 180°, you'll see one of your face isn't flat. You could just set it to 179°, or rework your geometry to have flat faces.


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Creating Zspheres in Blender. Trying to add CTRL + A to geometry node modeling
I have been trying to make a form of Zspheres in blender. I have gotten ico sphers at the vertices, and generated cylinders on the edges. I am having trouble changing the scale of each individual vertices. using "S" hot-key doesn't work, nor does "CTRL+A". Can someone help me out?
{UPDATE} It works!!!Thank you once again to Crantisz for helping me find the missing piece to my puzzle. You sir/mam, are an absolute boss. Anyone who wants to use this setup can go ahead and copy it, I would love to see how people use my little pet project. Tag me on istagram,@sonne3d, so I can check them out.

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

You can use vertex groups for that:

Enter the vertex group in the modifier

And use it:

Thank you so much man. I have been yanking my hair out over this for a few months now. I tried out your additions to the node tree, and it worked like a charm. If you would like to use the setup, please feel free to add it to your arsenal. And anyone else who wants to use them, go right ahead

The only issue I am having is when the joints are close together they are effecting each other unlike how yours shows, they are warping when moved closer together.
Something in the setup I am missing.
I set the radius input type to float, flipped the field from input to attribute and set vertex group: group
I realize they are sharing the same circle loop to bridge, they need a unique loop per each edge.


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How to add/edit tag of an asset from another asset library using python (add-on)?
This link specifies how to add a new tag to an asset present in current file.
After adding a new asset library, I want to add a tag to the assets present in that library.
This link mentions that it is not possible through Blender UI and it also mentions that it is possible through add-ons.
asset_libraries = bpy.context.preferences.filepaths.asset_libraries
for asset_library in asset_libraries:
    library_name = asset_library.name
    library_path = Path(asset_library.path)
    blend_files = [fp for fp in library_path.glob("**/*.blend") if fp.is_file()]

    for blend_file in blend_files:
        with bpy.data.libraries.load(str(blend_file)) as (file_contents, data_to):
            print('file_content objects : ', file_contents.objects)

The above code prints an array of strings, i.e., all object names.
I want access to the object itself, in order to add a new tag to it.
Any help or direction would be great. Thanks!

bpy.data.libraries.load lets you import items in your current file, but it doesn't let you modify the data in the other files (AFAIK). So unfortunately you do have to individually open all these files, add the tags, then save the files.
import bpy
from pathlib import Path

tag_name = "My new tag"

asset_libraries = bpy.context.preferences.filepaths.asset_libraries
for asset_library in asset_libraries:
    library_name = asset_library.name
    library_path = Path(asset_library.path)
    blend_files = [fp for fp in library_path.glob("**/*.blend") if fp.is_file()]

    for blend_file in blend_files:
        bpy.ops.wm.open_mainfile(filepath=str(blend_file))
        for obj in bpy.data.objects:
            if not obj.asset_data:
                continue
            obj.asset_data.tags.new(tag_name, skip_if_exists=True)
        bpy.ops.wm.save_mainfile()

Link to the docs
Plugging my (free) addon which lets you batch set tags, author and other good stuff from libraries from the Asset Browser interface :
https://github.com/Gorgious56/asset_browser_utilities

I have updated the code and it is crashing on open_mainfile() in add-on.

@KarthikNagaraj It's best not to modify the question too much because then the answers becomes irrelevant :) Without seeing more of your addon code it's hard to say why exactly this happens. Usually these kind of crashes come from the context not being initialized correctly. Using a timer to pause the script a little bit can help : https://docs.blender.org/api/current/bpy.app.timers.html

I am using from pathlib import Path whereas, your code uses from pathutils import Path and usind your import gives me error:
ModuleNotFoundError: No module named 'pathutils'

With a couple of timers, I was able to open multiple blend files one by one, add tags to all assets, save the blend files and re-open the original file(where the script execution started).
Thanks @Gorgious

@KarthikNagaraj glad it helped ! If you want to, you can modify my answer or add a new one to showcase your solution, might help other people in the future. Cheers :)


text:
Can i automate object duplication and relatives modifiers parameters?
I created a section of a rope and assigned it to a curve. I now have to repeat the exact same process for other curves, each time duplicating the section of rope and changing the target curve in the modifiers. Is there a way to automate the process with a script?
The object to be duplicated is called "00_Rope"
The curves collection is called "Curves"
The curves names are "ObjNurb", "ObjNurb.001", etc
I need to add an array modifier set to "FIT_CURVE" to each duplicate and a Curve modifier.

Yes. This is exactly the sort of thing that Python scripts are good at.  You might want to follow the "Scripting for Artists" tutorials on YouTube to see how easy it would be to write your own.

if you want that somebody of us should write it for you, you have to give us much more details - e.g. what you mean with "section of a curve" - what the names should be and so on. With so less information we cannot do so much...or you learn it by yourself as Marty said, but as bloody beginner you would need weeks without help - i would guess. But yes, the answer to your question is yes.

I added the information you suggested, as I reckon I have not been specific enough. I tried scripting some myself but I seem to have the most problems in getting the the data right when getting the object to duplicate and where to get each new curve. @Chris

You might be interested in a 'Ropify' GN group

ok, this script does what you want:
Before you run it, save your blend file with a different name so you can get it back if it doesn't work. (in other words: make a backup)
Select your rope object, then run the script.
Big thank you to relaxed who helped and explained me how to improve the script:
import bpy

def addCurveToNewObject(obj, curve):

    bpy.ops.object.duplicate_move(OBJECT_OT_duplicate={"linked":False, "mode":'TRANSLATION'}, TRANSFORM_OT_translate={"value":(-0, 0, 0), "constraint_axis":(False, False, False)})
    bpy.context.view_layer.objects.active = bpy.context.selected_objects[0]

    if len(bpy.context.selected_objects[0].modifiers) == 0:
        bpy.ops.object.modifier_add(type='CURVE')

    bpy.context.object.modifiers["Curve"].object = bpy.data.objects[curve.name]

col = bpy.data.collections["Curves"]

for curve in col.objects:

    obj = bpy.data.objects["00_Rope"]
    bpy.context.view_layer.objects.active = obj #sets the obj accessible to bpy.ops

    addCurveToNewObject(obj, curve)

@ Chris bpy.ops.object.duplicate_move() creates a new object that shares most of the data blocks with the original by default, including modifiers. The Curve modifier is already there, only the target curve needs to be changed. In the function you might delete everything after line newCreated = bpy.context.selected_objects[0] and insert newCreated.modifiers['Curve'].object = bpy.data.objects[curve.name].

You probably noticed that there is one rope object more than curves after execution. The original object is already assigned to a curve, but a duplicate is created for each curve, including the first one. One way would be to change the loop call to for item in range(1, len(col.objects)): and call the function with addCurveToNewObject(obj, col.objects[item]).

Thank you relaxed! I will update my answer soon. Not at my laptop in the moment.


text:
How to create reusable Python component
This follows from Garrett's fantastic answer here: In Python, given x-value on 2D Bezier Curve, return y-value
(EDIT: question generalised as per suggestion)
Say we have a Python file Foo.py containing the function X(p,q)
I would like to set things up so that my scripts can call X(...), rather than have to copy-paste its definition into each script that wants to invoke it.
How to accomplish this? And where is the right place to put Foo.py?

This question appears to be off-topic because it is about python module / package organization and nothing blender-specific.

this question would be better suited for stack overflow

This question seems on-topic because it requires a Blender-specific answer (see my and Pi's answers).

Glad to hear you liked that function I wrote!  But perhaps you could streamline the question, so make it more generic and get rid of the references to getYfromXforBezierObject, NumPy, etc.  You could just call the function foo().  It just seems like there's some extraneous details...

Sorry all, I have rewritten the question. I think that the question of "where to put the file" does have some specific 'Blender' relevance. (I can see that "How to access a function from another file" OTOH is a pure Python question")

You could save the file into the site-packages directory, which is found by going to your Blender folder and then 2.70 > python > lib > python3.3 > site-packages.
Say your file is called "Foo.py" and has in it a function
def X(p,q):
    return p + q

then, after saving it into site-packages, in the Blender text editor or console, you could use:
from Foo import X

I figured out what I need to do.
I have my own ~/Dev/BlenderScripts folder (as per http://wiki.blender.org/index.php/Doc:2.6/Manual/Introduction/Installing_Blender/DirectoryLayout)
I set File > User Prefs > Scripts to "/users/pi/Dev/BlenderScripts"
(Note: using ~ does seem to work but it doesn't show up on sys.path; I have filed a potential bug: https://developer.blender.org/T39680?workflow=create)
Then with the mouse over the 3-D view, I press F8, which reloads Python stuff.
Then I check in Blender's Python prompt by doing:
import sys
sys.path

And it will show up /users/pi/Dev/BlenderScripts/{ addons, modules, startup }
I then create modules/Foo.py, which contains function:
def X(p,q):
    print( (p,q) )

Then from another script, or from Blender's Python prompt, I do:
from Foo import X
X(1,2)

It appears that inside your scripts directory, there must be at least one of the directories: addons, modules or startup.  And you must put the file into one of these.  I know this is what you did, but could you make it more explicit (that part tripped me up)?

You have a full article on the blender wiki wich is going to help you:
http://wiki.blender.org/index.php/Dev:2.5/Py/Scripts/Cookbook/Code_snippets/Multi-File_packages
I've nothing to explain all is in the wiki.


text:
Create gridlines in Python
I'm making my own Python routines that distort space. I would like to visualise the effect of this distortion. To this end I want to create {x,y,z} aligned gridlines, so that I can observe the effect of the transformation on them.
So an x-aligned gridline would be say 1000 points between x=-50 and x=+50 with y=z=0, and the points would be joined to one another by line segments.
How could I create such a gridline using Python?
I found resources such as:

Scripts/Cookbook/Code_snippets/Three_ways_to_create_objects
askubuntu.com/..../how-to-make-a-mesh-by-using-python-script-on-blender
stackoverflow.com/.../how-to-create-a-simple-mesh-in-blender

but in each case it creates primitives from verts+faces, not verts+edges

You can create a grid primitive and remove the faces:
import bpy
import bmesh

sce = bpy.context.scene

me = bpy.data.meshes.new("Grid")
bm = bmesh.new()
bmesh.ops.create_grid(bm, x_segments=32, y_segments=32, size=50)
bmesh.ops.delete(bm, geom=bm.faces, context=3)
bm.to_mesh(me)

ob = bpy.data.objects.new("Grid", me)
sce.objects.link(ob)
sce.update()

This will give you a grid at origin, dimension x/y 100 and with 1024 vertices.

from_pydata():

it creates primitives from verts+faces, not verts+edges

You can either pass two sequences for verts and faces, or you give it verts and edges - it should work the same.

I've just completed a similar project. Here's what I had:
import bpy
# allows reading csv files
import csv
# currentstep is a csvfile with directory ie "C:\myfile.csv"
with open(currentstep) as csvfile:
    csvreader = csv.reader(csvfile, delimiter=',')

    #skip header row
    next(csvreader)

    #for each row, set x,y,z coordinates
    for row in csvreader:
        x=float(row[0])/100
        y=float(row[1])/100
        z=float(row[2])/100

        #create vertex
        vert = ( x,y,z )

        #append vertice to list of vertices
        verts.append(vert)

# CLONE ARRAY
vertsclone = list(verts)

# INDEX ARRAY edge from a to b
averts = []
bverts = []

# loops through vertices and connects them according to rule
# (rule = X & Y are equal)
while vertsclone:
    currentvert = vertsclone.pop()
    for vert in vertsclone:
        # check if x and y are equal; if so, add one vertex to averts,
        # the other to b vertices
        if currentvert[0] == vert[0] and currentvert[1] == vert[1]:

            averts.append(verts.index(currentvert))
            bverts.append(verts.index(vert))

            vertsclone.pop(vertsclone.index(vert))

# take list averts and list bverts and create edges by linking them together
# in indexed list (ie vertex 1 links to vertex 8)
edges = list(zip(averts,bverts))

# Create mesh
mesh = bpy.data.meshes.new("csv_input")
object = bpy.data.objects.new("csv_input",mesh)
bpy.context.scene.objects.link(object)

# create mesh data from python csv
# Verts are (x,y,z) Edges are 2-dimension lists of indices, ie (1,2); faces
# are n-dimension lists of vertices ie (1,2,3,4)
mesh.from_pydata(verts,edges,faces)
mesh.update(calc_edges=True)

You can modify the above at the Create Mesh step with whatever your rule for create the edges. In your case, you'll likely just create a set of vertices, and connect them as you go in a square pattern.
All you need to remember is that an edge is defined by a list of vertex indices.
So with mesh.from_pydata(verts,edges,faces) you can import any type of mesh data. If you just add vertices, it'll only create those. If you only add vertex and edges, you'll only get that. If you do vertex and faces, edges will be generated for themselves.
ie:
#mesh data for mesh.from_pydata
verts = [(1.3,3.2,4.2),(3.3,3.4,2.1),(3.3,3.8,3.6)]
edges = [(1,2),(2,3)]
faces = [(1,2,3)]


text:
Select everything except ears from mesh of head
I have a triangulated mesh (100k+ vertices) of a head.   I need to select everything apart from the ears, and reduce the vertex density on that selection by 16x or something.
Here is what I'm dealing with:

I've already asked a question on how to do that and got a very helpful answer: Reducing vertex density as distance from point increases
My problem is selecting the ears.  I would like to get a high level of control; simply using box select isn't going to cut it.
So I select a vertex path around one ear:

Now I'm stuck, can someone guide me?
What are the steps I need?   This is my guess:

somehow store the vertex-path
do exactly the same for the other ear
now might there be some tool like Microsoft paint's flood-fill,  where I just hit one vertex on the skull, and it will select be entire skull up to and including the boundaries I've just created (i.e. it will avoid the ears)
then I decimate, which I have instructions for

Is there some tool I can use that will just let me draw on the surface, and then  it will figure out an appropriate vertex-path?   when I do this on a 2M vertex model, it is going to take ages manually clicking 500 vertices.
EDIT: I got one step further:

I think youo are asking for how to choose the best selection method in this case, right? If so, I think the WIKI Indroduction for Advanced Selection contains all you need, actually.

What about using 3D view > Header > Select > Mirror for mirroring the selection?

@gandalf3 Mirror Selection currently requires strictly mirrored elements. I don't think it will work well in the OP's case.

@LeonCheung Good point, I didn't notice that the OP's mesh was not mirrored.

That is some nasty topography. 3D scan, I take it, right?

Yes, http://ir-ltd.net/  This is a good point; I've created a separate question just now to address it: http://blender.stackexchange.com/questions/5613/tidy-up-mesh-topography

Using circle select rather than box select might make things easier.
C, then click and drag, right-click to exit, middle-click to deselect rather than selecting.
EDIT: You can also use the mouse wheel to change the size of the circle.
(key word here is might, I don't know what the performance is like for you. I'm sure editing a mesh like that wouldn't be fun on my computer.)

Another way: If you don't mind adding some extra points on the model, you may also consider to separate ears by cutting them off using Knife Cut or Knife Project tool:

PROS: Almost perfect clean separation.
CONS: Add extra vertices to the original mesh. You may judge and weigh if this is acceptable.
Then CtrlG to add those vertices to a new group for the restraining usage in Decimate modifier panel.

If I was in your situation I would go to Edit more, clicked on Z to toggle to wireframe mode, and used combination of loop select/deselect (Ctrl + Left mouse to add to selected area, Shift-Ctrl + Left mouse to subtract from selected area). It would take a few iterations, but you should get what you want in a minute or so.
Positioning head for the first select so that two ears overlap in your view (for example by toggling to Ortho mode with keypad 5 and to Right view with keypad's 3) would speed things up. After you did first select -- it is better to avoid this exact position, so you do not unselect something you did not intend to.

One way to quickly select a string of vertices is by using the Select Shortest Path tool.

Select two vertices for the end points of the string selection:

Press Shortest Path in 3D view > Header > Select:

Result:

It only selects in straight lines, (no curving or circles) but I imagine this could speed up your workflow a bit.
You could use this to select your boundary and use Select Boundary Loop Inner-region.
Do this for both ears, then invert the selection (CtrlI)

One way is to hide the ears.
Once you have the loop around the ears selected

press H to hide the selected vertices
with the mouse over the ear press L to select all connected visible vertices
press H to hide the selected vertices
repeat for other side
simplify the mesh
Press AltH to unhide the ears

You may want to cleanup a bit around the edge that was hidden, but the hidden vertices will not be effected by any editing actions taken on the visible vertices.
You can also hide incrementally, so you can select a few vertices at the tip of the ear, press Ctrlnumpad+ to increase the selection then H to hide them, select some remaining ear vertices, increase the selection and hide them... till you have hidden the area you want protected.


text:
Understanding Fisheye
I set up a basic scene with a fisheye camera aimed at a sphere, with another sphere vertically above the camera, and another to the right (all three at the same distance):

(Note: Need that top pulldown on "Cycles Render")
Result is:

Now, I'm curious why the fisheye doesn't draw all three the same size. I was hoping it would fire rays out with an equal angle-gap.
Imagine we have a 1000x1000 image, and we are just looking at the 1000 of pixels along the centre-line, so (0,500) to (1000,500)
So I was hoping:
AngleBetween(pixel[1]-ray, pixel[2]-ray) == AngleBetween(pixel[501]-ray, pixel[502]-ray)

However, clearly this is not the case.
Why are the objects on the edge of the screen getting magnify-warped?
Is it possible to know what Blender is doing mathematically, without digging through the source code? (as far as I know, FishEye is a generic term for this type of warping, it is not an exactly defined projection...)
Also, is there any way to prevent this?
LINK: Spherical / Custom projection at code level

The problem is that you're trying to map a hemisphere (the view) onto a plane (the rendered image). There is always going to be distortion.
But you're right, you might be able to choose what distortion you get. Have a look at the various projections used in geospatial software. If you want equal angles, perhaps one of the equal area projections would suit you - although I suspect Blender's fisheye lens is already some kind of equal area projection.
As for implementing a different projection, you might be able to do it with an OSL shader, by placing a lens object in front of the camera.

+1 for a solution path that doesn't involve recompiling the entire Blender source tree :)


text:
Freestyle line set is drawing things outside from the view
I'm working on an office scene  with Blender 4.1 and I have created a freestyle line set, but it is drawing things that are hidden by another object, here I leave You the render with and without the freestyle line:

Hello, AdverickMegrezWD, it certainly looks as though Freestyle has been unable to detect occlusion, here,  possibly due to floating-point resolution? I think it would help folks take a shot at answering if you could share a stripped-down version of your file showing the error on https://blend-exchange.com/ . Then we could try out our solutions before posting.

Uploaded the Blend file


text:
How to change mid mouse button function for a keyboard key?
"The Summary"
I need to change shortcuts that involves, mid mouse button and movement of the mouse, specifically "The shortcut for the Pan View Function" and the user preferences only allows me to put a single key or the mouse only. How can I set a combination of keys and mouse for a shortcut?
"The large explanation"
For medical reasons I stop using mouse, now i use just the pen of my tablet, the thing is that the button on the pen that I mapped to be the central button of the mouse is breaking easily with the continuous use, I bought a second pen and now it is begin to fail, I want to replace the mid mouse button function with any other key "I know i have to do it shortcut by short cut, that is not the problem" the problem is that the user preferences menu only allows me to change it for a single key, I need a combination of the movement of the mouse and a key, How can i do it?

Thanks Duarte Farrajota Ramos and thanks a lot cegaton that was exactly what I was looking for, thanks man!

Click the little arrow to the left to expand the key mapping properties.
There you can choose from the predefined modifier key combinations (Ctrl Shift or Alt), or use any other as modifier.


text:
pannel Landscape
Dear Blender community,
I am new in Blender, and I build the landscapes for some specific application. After creating Landscape (Shift+A, Mesh -> Landscape), I lose the panel "Landscape." Do you know how to access this panel again?

Can I click on the created landscape to access its parameters?

I don't think "I lose the panel "Landscape." is really good explanation of your problem because it might be not clear what you expected that panel to do but it is your decision to edit the question

"Can I click" You can't

Amaizing note:
Note that you can only set the parameters at the time of creation of the object.


text:
How do I create an edge on a non-standard shape?
I am trying to create a horizontal line around a corner but Blender won't allow me to do cuts with crtl+r.
My intent is to make 4 edges so that i can make it go inward (it's supposed to be the lid of a box)

Some extra info: I am unable to use the knife tool (K) because from the front and rear view the box is obstructed and I don't want to cut a line through the entire model.
If there is a way for me to add a Vert on an edge with it being able to slide, much like the crtl+r shortcut does for edges that would be a way.
Edit: This was marked as possible duplicate where the solution was using the knife tool but like I said above I'd like to avoid using this as I'll have to make it "cut-through" which will cut the entire length of a 6m long model with a bunch of details.

The solution will be the same, removing the Ngons (visible in the screenshot) and tris (if any) as they will prevent Loopcut from working. It isn't important whether you're dissolving or adding geometry when fixing, e.g. you can dissolve the edge in the top of the left cube so there aren't ngons on its sides. Knife tool won't cut through the model if you disable Cut-through

But the side which isn't allowing the loopcut is a plane with 4 corners, not an ngon, that's the reason I had to make a small triangle at the bottom. The thing with the knife is that I can't make the cut unless I allow it to cut-through because of where the side is hidden in the model.


text:
Double faces on UV map?
I added seams to a cylinder that had a solidify applied to it, the inside is fine and is all connected on the UV map as it should be with the seams  I added but on the outside the majority are messed up with a bunch of duplicates that I can't delete.
If I do remove doubles it doesn't remove any verts and if I move the face either on the 3d view or the map it moves the same face with the same verts and edges connected? I've never seen anything like this...

If possible upload the file here https://blend-exchange.giantcowfilms.com/ and include link in the question or in comments. Usually if islands in the UV map are split to multiple small ones then there's something with the mesh. Removing doubles might not help due to many reasons, like too low threshold, too high threshold or something alike

download file is at the bottom, thanks for the help!

I can't tell how was that done but there are overlapping faces in the mesh which cause z-fighting, broken face loops and non-contigous uv map. Removing doubles won't work as expected due to small distance between faces to delete and faces to leave. I'd suggest removing those overlappings maybe even manually. One more flexible approach is removing solidified geometry and using Remove doubles

How do I go about removing the double manually? removing the face seems to delete "both"?

It doesn't delete both, that's what is shown in the gif. There are some faces which are not overlapping though. To remove solidify see https://blender.stackexchange.com/questions/81583/quick-way-to-remove-solidify-thickness

I deleted the entire thing and remade it with extruding instead. Thanks for the help.

Smart UV Project works for me on 2.79. I added a primitive cylinder Edit/Face mode/deleted the cylinder top face. Back to Object mode/added "Solidify Modifier" (BTW hate that name), applied "Solidify Modifier". Back to edit/face mode, select all/apply Smart UV Project at default settings. Result is fine.
So are you saying that the faces/verts of the outside of the cylinder are locked to the inside faces/verts?

I'm not using the smart project, I'm manually unwrapping. and as far as I can tell on the model it all looks good, just looks like some faced are duplicated but they aren't...


text:
Draw visual bounds around UV islands
Is there any way to draw visual bounds around UV islands to represent edge padding?

What do you mean by "visual bounds"? Do you want to draw in some way line along the bounds of each island?

Yes, exactly that. A line that is offset by a set number of pixels.

By a set number of pixels? I don't think it's possible to do with that precision. You can use Face selection masking when painting to select one face of the UV island, use Ctrl+L to select all the faces from that island (there should be seams for this to work) and enter Texture paint without deselecting; then with Face selection masking you will paint only on one island. That doesn't provide with precision of how many pixels do you want to paint

I’ve added a picture to illustrate what I have in mind. This is to ease up manual UV packing when trying to keep certain distance between islands.


text:
When I add text to blender it disappears when I start the game engine
When designing my game using blender 2.79 when I start the game engine the text object added disappears:

can you attach your .blend via http://blend-exchange.giantcowfilms.com ?

please don't duplicate questions... https://blender.stackexchange.com/questions/92830/text-disappers-when-i-play-game-in-blender-2-79

Your file is fine on my laptop. I can see the text.

I can see the text as well when pressing p. Maybe try to update your graphics driver or reset blender settings?

I just solved the issue. I had earlier changed the ui font of my blender. So it made the text object invisible when I render. I had to reset my preferences.

I just solved the issue. I had earlier changed the ui font of my blender. So it made the text object invisible when I render. I had to reset my preferences/settings.


text:
Why is Density not showing up as a source option for my Voxel Data?
I am following a tutorial and I am working on smoke right now. However, it will not render due to the voxel data not having Density as a source option even though I followed the tutorial. This is my screen:

This is the tutorial's screen:

And yes, I do have a Volume material on the domain object.

The options for that setting were changed in 2.65, which was part of the addition of fire.
In older versions like in the tutorial, only smoke data was used to define the density of the volume, with the addition of fire, there are now two sources. Previous options of Density, Heat, Velocity were changed to Smoke, Flame, Heat, Velocity.
If you are only simulating smoke then use Smoke instead of Density. If you have fire and smoke, then you can create a texture for the fire data and another for the smoke data.

I believe I tried this, but nothing showed up when I tried rendering the image. It was a blank screen, but I have lamps placed and followed the tutorial.

I just tried again, and the same thing happened; when rendered, it is just a black screen.

If the whole render is black then it won't be your smoke texture. This question has a lot of solutions to black renders. Did you set the material density to 0.0 before doing the texture? Where is your camera? can the camera view more than the smoke sim? it may be that your smoke domain fills the camera view - in the viewport change to rendered preview while you know that you can see more than the smoke.


text:
Area of mesh moving along bone despite not being weight painted
I have made a simple character model and am adding a skeleton to it, so i can use it as reference and so i can get a feel for how rigging and weight painting are.
The white box (Shoulder_L) has weight and is the one linked to the bone that's within it, however for some reason some vertices in the right arm move when i pose the shoulder, despite not having any weight.

(The area within the circle is where the vertex that moves is located)
Blend File

The right arm and shoulder have weights form Arm_L bone that are causing the deformation.
You can clearly see it when in vertex selection masking and adjusting weights levels in the Weight Tools panel.
To fix that problem set weights from Arm_L on the right shoulder and arm to 0, or use Subtract Brush on that areas.


text:
Objects disappear in eevee render blender 2.8
I just downloaded Blender 2.8 beta and when I try to render any object in Eevee engine, the object disappears and only the outline is shown.
Here is my model in the layout mode -

and when I click on render and choose Eevee engine, this is how it appears

Although in cycles render, it looks perfect

Could you please help. I know it must be a setup issue but there is no help available online either
Uploaded the model here -

The light strength of EEVEE and Cycles sometime don't match. Try to increase the strength or change your light source

I tried with sun and spot light. Nothing seems to work. In fact the object does not show up in LookDev mode either. Definitely looks like a setup issue although unable to wrap my head around it

If you can upload your file here https://blend-exchange.giantcowfilms.com/ then add the provided link editing your question.

Uploaded the model

I have a similar problem with EEVEE, I changed camera angle, added extra lighting and finally downloaded 2.82 but it did not resolve the issue. when I rotate the camera around a set of objects it will render perfectly in preview, all looks sweet, but in the final render with certain angles it starts dropping objects from the scene. I am now running it in Cycles to see if that resolves the issue and that seems to solve it, not sure yet because in Cycles this animation will take a lot more time

Totally work fine with me.

Try to load that file in a clean UI(don't load UI) and another build of Blender 2.80.
Also the data in %APPDATA%/Blender Foundation/Blender/2.80(Windows) should be cleared for new preference. (or load factory preference)

Downloading a new build help resolve this issue


text:
Can I specify the direction along which Edge Slide follows?
I have an issue related to Edge Slide.
During Edge Slide with mouse, I can specify a direction along which moving edges follows WITHOUT clamping by disabling clamp (by depressing C) when the edges move along a desired direction. (see the video in the link)
Issue
After operating with mouse I want to numerically specify the slide amount.
However the direction is reset to the default direction after typing the numeric amount.
Can I specify the direction?
Thanks

Not a solution, but you can specify slide amount numerically during Edge Slide operation (before confirm). As for me, it's looks like a bug, maybe you need to post bug-report?

@Crantisz
Thanks for reply in the comment :D

you can specify slide amount numerically during Edge Slide operation (before confirm) Ah, it's practically a good enough solution. However I'd like to post a bug report (or question?) for this issue. Thanks

Also change the clamp setting when you alter the operator properties.

I think what you are attempting can't be done. The direction of the slide isn't following any edge which is why it snaps to the direction that has an edge to actually follow. That suggested a workaround: extrude and scale (shift-Z) to create edges for the slide to follow. I just tried it to test and it allowed numerical entry after setting the slide direction. An easier solution is shown below. Simply snap the cursor to the pivot point you require and scale from the cursor. Hitting S->shift_Z->numerical value:

This is kind of difficult to explain, but you can lock the slide into a specific angle by holding Alt at the right time.
Step by step:
The problem
For reference, this is what the unmodified mesh looks like before we start:

I try "lift" the window sill edge up by Pressing GG, but it fails (the wall unintentionally gets thinner):

So we press Escape try again.
The Solution
Notice the small yellow line above? That's important - we need to adjust its angle. You hold Alt to achieve this, BUT - you need to do this before it's at the wrong angle.
In this case, I first GG slide the edge down:

Notice how the small yellow line now points in the direction I need it to. Now, while in this position, hold (and keep holding) Alt while you slide. It will now lock that direction in place:

Finally, click the mouse or press Enter (all while still holding Alt) to lock in place.
This trick can also be used when selecting multiple vertices in completely different places.


text:
Strange Twist in Bezier Curve
I am trying to add a simple 2G timing belt to a pair of pulleys.  I am using a bezier curve with some modifiers to replicate a belt tooth long it.  Things seem to be going ok, but for some reason, there is a twist at the top of the curve and I cannot figure it out.  Specifically, the teeth are pointing out at the top and pointing inward (the correct way) along the rest of the curve.  Additionally, at the transitions to the top, there is a violent twist?  A picture is worth a 1,000 words right:

Can somebody help me out here so that all of the teeth are pointing to the inside along the entire path?

Blender 2.90.0 (2.90.0 2020-07-30) on MacOS 10.15.5

Compare to the default setting of curves, twist method was changed. I'm not very sure what's this setting doing. But set it back to Minimum will solve the problem.

Reply to the comment
Select all the points than set the Mean Tilt to 180 degree.
(Actually you can control the rotation of any point one by one. Just choose the points you want to twist than use the Tilt button from the left sidebar. Than click and drag the yellow circle.)

Humm.  I tried that with no win.  I will try it again.  I also noticed that the belt is backwards in your screen cap.  Is there an easy way to reverse it so the teeth are pointing inside?

Yes there is a way to control the twist. Check the second part in the answer:)

Cool.  Will give it a try in a few minutes.  Thanks.


text:
Use of Curve Modifier to Make G2 Timing Belt
I have been trying to get a G2 timing belt to work in Blender.  All in all I think this is conceptually a pretty easy task as outlined by https://www.thingiverse.com/thing:411517.
Make a core repeatable pattern...
Use the array modifier to make it longer...
Use the curve modifier to put it in the right place.
Ok, I cannot seem to figure out what the orientation should be to make the core part (one tooth of a GT2 timing belt) to look right.

Can somebody take a quick look at this file and tell me where I am going wrong?
(I did this before and got it to work, but again, I seem to be stuck and not sure where I went wrong.)
Blender 2.90.0 on MacOS

You've scaled down your curve and applied the scale, now its vertices raidus have been scaled down as well and you need to bring it back to 1: Select your curve, go in Edit mode, select all, open the N panel > Item > Mean Radius, choose 1

@moonboots Thanks for the pointer.  I have added an answer below for this.  I now need to go and look up what the Mean Radius parameter means. :).

Thanks to @moonboots for the comment pointing me in the right direction.
The answer was to go into edit mode for the curve, select all the points, and then set the "Mean Radius" for all of the points in the curve to 1.
If you "apply" a scale to a curve object, the radius of all the points is subsequently changed from its previous value to a scaled version of the radius.  Blender is simply "applying" the scaling factor you have selected to some of the internal properties.  For example, if you scale your curve by 0.5, then the radius for each point is then changed to 0.5 times its original value.  Typically, the radius is set to 1 (unless you are doing something interesting and fun).  Then when Blender uses the curve in a curve modifier, it will scale the original object by the values in the radius as it is placed along the curve.  This is why setting the radius back to 1 (i.e. no scaling) fixes this problem.

actually it's the scale applying that has changed the vertices radius, if you scale down the curve to 1/3 of its size, the radius will remain 1, but if you apply the curve scale, the radius will be scaled down to 0.33. It's not a bad thing to apply the curve scale, but don't forget to bring the vertices radius back to 1

Right, that is why I specified "Although you might have applied your scaling". Let me see if I can edit my answer to be a bit more clear about that point.


text:
Lighting a room with true to life lamps
Ok, I know that this question must have been asked before, but I am having a hard time finding the right posts or finding an online tutorial which will help me get past this.  Here goes:
I am trying to replicate my basement right now and I am struggling to get the two lights which I have in the basement to correctly light the room.  It seems as though the picture is very grainy and does not get a lot of light although I have the lamp power turned way up.  I have downloaded a simple light fixture from online and then placed a lamp inside of it.  I have tried to use area and point lights with no real success.  I have edited the "glass" material to be a mix between the glass and the transparent shaders.
I am really at my wits end as this is simply not working as my gut would tell me.  Also, there seems to be a large difference between when I render the scene and when I just change the viewport mode to show rendered.  I would be grateful for any help on this.  Any other advice is also welcome.  I am not a blender regular and just starting to get my hands dirty here.
Configuration
Setup is OSX 10.13.1.  CPU rendering on Blender 2.79.  Using Cycles
Blend file

Example Images
Render

Viewport Render
Note: This image was scaled to meet the max file upload requirements of 2MB

This tutorial is probably the best ever for realistic lighting. (Does cost money)


text:
How to dynamically simulate physics with python?
I try to simulate dynamic behavior in blender using physics for rigid bodies.
Some objects should fall down onto a moving plane.
(there is a previous question related to that:
animation locations with python
but the positions seems just to scratch the surface of the problem).
I would like to animate the plane depending on the falling objects positions, so that they interact with the falling objects (e.g. do rotations of the plane).
But I would like to set coordinates dynamically while running the simulation
(running the animation here means: counting scene.current_frame manually).
One aspect of the simulation works fine: if I increment the current_frame,
the objects with rigid_body = active do fall down.
But changes in rotations of the plane seem to be not recognized.
A bpy.ops.transform.rotate(value=2,orient_axis = "X")
seems not to be recognized during the animation.
Is there a way to consistently implement dynamical changes
of the environment while stepping through the frames
(without adding keyframes for the dynmaically changing rotation and position of the plane, ) so that they dynamically interact with the rigid_bodies?
The planes physics property is set to passive rigid_body.
To demonstrate the issue, here is the blend-file:

Please run the script, which starts a frame_handler.
Then start the animation (from frame 1 to 100).
In frame 10 the cup is turned upside down from the script.
this is visible in the viewport, but the sphere still seems to
falls into the original (unrotated) cup. So the physics calculation
does not seem to recognize the rotation, althought the
viewport does.
So how can I inform/adapt the environment, on which the physics calculations rely about/to the changes in the cup rotation?
-> edit: one additional thought after experimenting with the
physics parameters:
if I also set the cup as an active rigid boy (and place
it onto an additional plane, which is passive then),
the rotation will be integrated into the physics simulation.
but this unfortunatley has the side effect, that the dynamics
of the system is compelelty differnt. To fix this, might
be more complicated than to understand the structural
way blender python interacts with the physics environment.

edit:
I found some interesting information here:
https://www.youtube.com/watch?v=YpUyGJ-do4o

So following the ideas in the video one approximation to the combination between external control and integration into physics calculation could
be to set the rigid body settings to "animated" in e.g. each odd
frame, and then to "dynamic" in each even frame.
This allows a possibilty to set positions and rotations via a python script and let the changed values be incorporated into the
physics calculations.
Anyway: even better would be a bpy way to set positions
directly into the physics world in arbitrary frames,
to get a fluid frame by frame simulation with external control
of some objects.

I tried this:
      frm = scn.frame_current
      if (frm % 2) == 0:
          cup.rigid_body.kinematic = False
      else:
          cup.rigid_body.kinematic = True
      cup.rotation_euler.rotate_axis('X',math.radians(rotVal  ))

and it surprisingly works.
Here is the blend file:

Of course this is only an approximation. Even better would be to
directly change the data, which are actually taking for the physics calculations to  have more control about the simulation.

Meanwhile I found out, that usage of drivers (using an empty as driver to control the rotation) also solves the problem,
so that circumstancial resetting the kinematic-variable is
not necessary with  this driver-approach.