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How to combine the multiple collections as a collection in geometry node?
I wonder how to combine the multiple collections as a new collection for instancing them on points in Geometry Nodes.
For example, I have 3 selected collections and want to random array them on a spline. I know we can make it easier by putting all unit objects into one collection but this way will not be effective anymore when you have more than 50 unit groups that need to be separated to collaborate with other nodes and some of them need to combine for nodes like this.
This will be very helpful to me for adding new future collections or changing to another combination option using the Switch Index Node.

I tried to combine them using "Geometry to Instance Node" but they made the overlapping at the collections that have multiple unit objects like Group A and B.
You can take a look at my example file (Blender 4.3 Version).

Just a simple recommendation: objects can be linked to multiple collections. Let's say you have a blue cube, a red cube, a blue sphere and a red sphere. Then you can make a collection "blue" which holds blue cube and blue sphere, collection "red" for red cube and red sphere, collection "cubes" for blue and red cube, collection "spheres" for blue and red sphere and a collection "all" which has all four objects. This way each collection can be used separately in Geometry Nodes but you can work on "all" as well.

@GordonBrinkmann How do you do that ? I've seen something similar in the doc concerning collections, I don't quite understand the process. Sorry if it's something obvious. Are you talking about GN, or about the outliner ?

From https://docs.blender.org/manual/en/latest/scene_layout/collections/collections.html#collections-menu: Link to Collection Shift-M :
Add selected objects to a collection, while keeping them in their current collection. This way objects can appear in multiple collections. A new collection can be created in the pop-up.

Amazing, thank you monseigneur !

Gordon, the linked objects for the combination collections work well when you just want some specific options. But it is not a good idea if you want a lot of random options. Maybe with more than 100 options of the combination then you have to create 100 collections manually, I guess. Not to mention that you add the new future unit objects and more options as well. So, Markus von Broady's answer below is the solution for this. Thank you for your advise.

@EricNguyen Never said it was a perfect solution, otherwise I would have written an answer. Some people are just not aware it is possible to have objects in multiple collections (see comments above). Also I never said you have to create collections for all combinations, that was just an example. As I understood the question you already have objects in different collections for different purposes and want to keep them. So my suggestion would have been now to create just one more collection, select all objects from the other collections and link them to the new one to work on them together.

It looks like you want to realize your instances with depth of 1:

Imgur mirror (SE image hosting has problems)
With this setup I don't see z-fighting of various colors, also text doesn't overlap.

Great, Markus von Broady . This is exactly what I want for the combination options. Thank you.


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Help with smoke simulation scaling and appending
I am putting together a preset pack of different types of smoke simulations (explosions, candle flame, after burner, exhaust etc... )
I would like the user to be able to append any of the smoke scenes to their scene. The only problem is if their scene is not to scale, when they resize the smoke sim to fit their scene it will drastically change what it looks like.
Is there some sort of Simulation scale feature they can use?
Or can anyone think of a creative way to help the user be able to scale the smoke sim and have it look the same at any scale?
Here are some examples:
Let's say this is the original sim that I always want it to look like.

This is a brand new blend file with the smoke scene appended, with the smoke sim copy and pasted to the new scene and scaled down (or up doesn't matter), the scaling has NOT been applied.

This image is the same but WITH the scaling applied.

In these examples there is not much of a difference between the NON-applied and applied samples (but even between these there are differences, especially with some of my other sims).
I understand that the scale affects how the smoke looks. The solution I am looking for is to have my original smoke sim to look the same no matter what scale the user uses.
I am using openVBD.

"drastically change what it looks like": can you include pictures? Is the smoke a 3D texture or openVDB?

You need to adjust the density for how much you scale the smoke. If the original scale was 1.0, the new density is:
$$
density' = density / scale
$$
If you want exactly same render result (from scaled camera closer/further from smoke), you will also need to adjust the Volume Sampling Step Size under Properties > Render Tab > Geometry:
$$
stepsize' = stepsize * scale
$$
The density can be adjusted by a driver from the material node tree. I added extra node, so the user still has the option to manually adjust:

The driver looks like this, I chose the Z axis as input:

The others can be locked from user input and their value copied from Z axis with drivers:

Can confirm that this works with no real difference.

Awesome I think this is what I needed, I am a complete noob at Python, but would you suggest I create a simple button that the user clicks after scaling and positioning the smoke sim to there scene, so it automatically applies those formulas above? is this doable for a complete Python beginner? Thanks Omar for confirming.

@icYou520 You can add driver to the node value, use scripted type and drive the node value with the scale (choose some axis). You should then lock the other scale axis and drive them also, so the object is forced to scale uniformly. Is this something you are comfortable doing or would you like me to include it in answer in more detail? I would leave the Step Size for each user to set, because that setting depends on the HW they are rendering on. You can notify the users this setting does influence the render quality of the smoke and the render time.

That sounds like a much better solution. If you don't mind showing me how you would do it with a driver and scripted type I will be very thankful. If you are ever in Southern California I owe you a beer. I will make sure to award the bonus too. Its making me wait right now.

source: Stack Exchange

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

sort: votes


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Gear motor fine until it touches other gear
I'm trying to create a planetary gear system, following the tutorial on YouTube, following everything to a tee.
I have finished making the sun, planet, and ring gear, yet once the sun moves and touches the planet, all animations jam up.
So I remove the ring gear and 2 planets to leave me with 1 sun and 1 planet for simplicity sake. Then I go another step and I remove the planet, and the sun rotates again freely.
When I reintroduce the planet, the sun will spin slowly fine. Then it touches the planet and jams.
Would anyone know what causes this issue?
Link to my file on Youtube.

Please add your blend file, so we can check it out

Hi! it's hard to understand your problem without any reference. You should add screenshots or a blend file to make sure people can understand your problem and also most of the people here are not patient enough to go through the entire tutorial and understand your problem.

try solving the problem by verifying your setup with the blend file shared in the youtube video description.
And if you can't figure it out then edit your question by adding more details and your blend file :D

Hi, thanks for getting back to me. I've just uploaded the fie unto Youtube. The first clip is the whole planetary gear. The 2nd clip shows me simplifying everything down to just the sun and planet to see if the mechanics will work.

link is: https://youtu.be/_rxy2Zmk8xU

As Chris asked - blend file would be probably needed ... in meantime check "Face orientation" (Normals direction) of those objects.

How do I upload the blend file on this forum?

Use https://blend-exchange.com and copy-paste given code to your Question via edit. Your Q would be probably closed, external links as main source of informations are not allowed, they are not permanent. Please add some descriptive image (or animated gif) to illustrate issue. Even you solve it, this site is knowledge base, so others can learn from your issues. Thank you keep this site organised.

I checked out the face orientation and saw the values were messing up the gears. I played around with the pattern and got it all working now!

You'r welcome. Just same as my comment above ... I edited answer here for you so it better fits to BSE guidelines. Please do similar for your Q. Thank you ... BTW it should be all blue :)

Okay thanks again! Blue! And questions to the blend-exchange.com. WIll do!

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


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Blender "eats" frames as I render animation with video as plane's texture

So I want to make a lightsaber.
As I animate glowing plane on top of video (I used a plane and then added video as texture as advised here) everything seemed fine. The plane was aligned with the stick I was holding in my hand.
Then, as I started rendering the whole thing, animated plane started lagging behind the video. It was like Blender skipped and duplicated frames whenever it wanted to. Any suggestions on how to solve it?
One more thing. I duplicated the "video plane" so that lightsaber isn't visible as it passes behind something. Also, I finally managed to align everything, and render was ok. As I came back to the project after rendering, it was missaligned again, but next render looked fine.

Hello, could you add a few screenshots of your setup ? The description is a bit confusing. Make sure you don't have rogue keyframes in your object's animations

Ok, added few. This "side view" are mentioned earlier planes I used as masks

I'm also a bit lost in your explanation ... when you "...managed everything, render was OK." ... you mean single frame render? Also "... but next render looked fine." Like when rendered anim again it was OK? BTW are you sure your video is at 30 fps like blender's fps is set now?

Is the video a video file or an image sequence? I try to always work with image sequences because it's less likely to have codec issues or framerate issues. Try exporting the video as an image sequence using a video editing software (I'm pretty sure you can do this in Blender, but I'm not familiar at all with Blender's video editing tools) and then use the image sequence as the texture. I believe this sort of problem won't happen then.

@vklidu I meant animating it basically frame by frame again. After that I rendered it again and it was fine. The video should be in 30 fps. It's recorded with phone, so maybye that's an issue, but in file properties it had 30.01fps. So yes, it's a video. I tried again while waiting for an answer and it seems, that it got messed up after adding these mask planes. Now I added them before animating the blades and it seems to be working fine


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How to align bottom of picture to ground when loading it?
I'm planing to do a simple animation of my drawings (scrolling and parallax effects with a camera).
Each time I'm loading a new Image as Plane, Blender align the center of the picture to the cursor, like this:

I was wondering if there's a way to automatically load the image ABOVE the Z axis, like this:

For now, i have to do this manually, which add quite many extra steps. Since I'm planning to load quite a lot of pictures, it would be a time saver.
I'm planning to have this type of result, just so you have a better idea of my humble project:

Current import Images as Planes addon doesn't have this feature ... so before some pythonist comes to help ... Blender is bundled with Align Tools addon. If you import all Images as Planes you can use addon to adjust them at once ...
Search for Align Operator
(or go to side panel (N) > Item > Align Tools > Advanced)

choose Object / X, Z / Min / Min it aligns all objects to left-bottom corner

then switch to Pivot / Active / Min to place Origin (Pivot point) also to left-bottom corner

Or use any other option ... to move all object to a World Origin (X0/Y0/Z0) press Alt+G

Thank you very much for your answer. It will help me to save time by avoiding some repetitive manipulations.

You'r welcome :) Consider mark answer as accepted so others can see it as solved and system is not pocking it in repeatedly ... https://blender.stackexchange.com/tour ... You can change it anytime to another A, like if someone will extend or rewrite the addon for you. Thank you keep the site organised.

Another way ... also not automated, but quite efficient is
under Options of 3D view header to Affect only Origin.

When enabled Snapping to Vertex

And Alt+G to Clear Location that now moves all images to zero location by bottom edges of images.


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Uv map messed up, textures and uv map do not match
i've extracted a model from a game because i'm creating a mod, i've already made the textures but for some ideas i wanted to modify the meshes BUT, whenever i try to put texture on it, texture are messed up and second, uv map is messed up too, i would like to understand if i m making a mistake or not,
texture in shader editor is color to color, alpha to alpha
when i unwrap in the uv editor all the vertices are fit incorrectly (Img 04) as you can see the mask doesn't fit the texture, the same goes for the shell, i.e. therefore i cannot put the texture correctly
hope to find someone that show me the right way cuz i m not understanding where is my mistake... i want only to understand where i do wrong,
i can give more information if you need, i think i explained everything to help me out, follows the screens, thx to everyone.
Texture messed up

UV Map messed up

Shader Editor

UV Map unfitted

it's not clear, you've unwrapped your character, given him a texture that works fine, then reworked the topology, then re-unwrapped?

Whoa thx, i explain everything, i ve extracted the model, i imported in blender the ,rip files, then i linked the texture via the shader editor, i didn't changed yet the topology, i ve only worked on the original one to match the textures, nothing else, texture and uvmap of the model just extracted do not fits, that s the major issue, the same goes if i work with .obj files,i've both so if can be useful to solve i can work with the objs thx to everyone

cool, thx Vklidu, i think i can share it now, this is packed with textures, shader, about the uv map i tried today too to fix but few things, looking at the shell you can see it s different, nope size is about 1.7 Mb no problem at all

ah sorry i thought i did, my bad, i will upload a new one, now the file has been packed, about your question, from .CPK original format file from the game, i extracted with ninja ripper, in format .RIP, and from those files i started working with blender, btw the data in my files are the same .RIP files extracted, i didn't make any change, therefore you are working with the original ones, thx a lot Vklidu

Hi there Vklidu, the "mess" comes out once i want to add the texture to the mesh, i think is a blender related matter if the texture do not fit the meshes, i m asking, ah yeah is there something about fixing the uvmap using softwares like Photoshop then re-add the texture in blender, could be my case? could it be useful? i heard about this generic fix for any case not because could be related to my case, thx a lot

Sorry this discussion is not moving forward. Sure, you get the mess when you add texture in blender, but this mess comes from wrong UVmap that came with model (if you didnt unwrap). UV doesn't match the texture, that is not a fault of blender. So there has to be another texture that match this UV or the UV was for some reason regenerated somewhere in the process of conversion (NinjaRipper or RIP). Photoshop can handle UV for 3D, but I don't thing it has better tools than blender).

The only way to unwrap UV that will match this texture is to use the same unwrap algorithm used for source. BTW UV on your two screens are different and also UV in provided blend is different so there was some manipulation. The last think I can try ... share your RIP file. I highly recommend to edit your Q, delete all unnecessary and add info about source format NinjaRipper app, .RIP conversion and share RIP file... and delete all comments here I will delete mine (if you want to attract others to help with your issue).

Hi there Vklidu, thanks for everything so far, the .RIP files are part of the entire mesh, so sharing it will be having an arm or the head and nothing more than that, i can share them no problem, just one thing what kind of info about the source format of ninja ripper do you mean? To sharing the .RIP file i can always use blend-exchange since is the the uploader used here or i need to use another hoster? Thx a lot!


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How to use vPython into blender?
I want to use vPython in blender. Is there any way to implement this into blender? I want to create physics animation. In vPython the arrow vector attached to the moving object is really fantastic which changes according to magnitude and direction of object's property (velocity, force etc. ). I want this in Blender scene. Any help would be appreciated.

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


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How to rotate bone group 90 degrees for all frames?
Let me preface my question by saying I'm a very newbie user. I have a weapon model and the arms need to be rotated 90 degrees for every frame for the whole animation (and i've got a few more weapon models that need this to be done, but unfortunately it's a very lengthy process.) Is there anyway I can change the Rotation of a bone group for all frames of an animation?
Here's a picture of what I want to do, if it helps:

Have you tried selecting the entire curve in the graph editor for the correct axis (the one you want to rotate around) and moving it up/down 90 units? BTW I can't see your picture...please post it with the BSE (Blender Stack Exchange) image tool.

i'll try that now, and I updated the image. thank you

First of all, you shouldn't have a keyframe every frame : )

maybe I got the terminology mixed up. i've just decompiled a model and want to apply the rotation every keyframe since it must have been edited in the decompile process. i can't figure out how to actually use the graph editor to change it for all of the future keyframes

The armature should not have really have keyframes on its object at all: just its bones. Then the rotation for the object could be easily applied with Ctrl-A > Apply Rotation.
If the above is absolutely impossible, you could try something like this, but I will warn you it'll get messy fast! This will iterate over every frame and apply the rotation, then add a keyframe.
import bpy

scene = bpy.context.scene

for frame in range(scene.frame_start, scene.frame_end + 1):
    scene.frame_set(frame)
    bpy.ops.object.transform_apply(location=False, rotation=True, scale=False)
    bpy.ops.anim.keyframe_insert_menu(type='Rotation')

You could also, like I said before, do something like this (if you're fine with the rotations getting screwed for the time being):

i need everything to rotate off of that center point, i don't want to rotate the bones individually if you get me, which is what it seems like this does. ill try your script out first! thanks

the python script failed: http://i.imgur.com/r02uQRY.png

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


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Crop out only a side of a video
I need to crop out only the left side of a video. Assuming this image is the video, i want to crop out the black side and maintain only the blue part.

Instead of black do you need nothing (crop) or transparency (Alpha 0)?

Possible duplicate of Simple Masking/Stencil in the VSE

I just edit the question. I need to crop out the black side

Normally you cannot crop (redefine) video size from VSE, since it's globally set in Dimensions panel under Render Tab. So you have to redefine the Resolution(s) after cropping in VSE to remove stretching effect:

With the strip selected, in the properties panel in strip input check image offset and image crop.
Under image crop enter the amount you want to crop to the left box and under image offset enter the same number in the x box.


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Delete frames from a video
I'm new to editing videos with blender. How can i delete selected frames from a video?

Related: http://blender.stackexchange.com/a/15376/2843

My best recommendation to trim videos by frames is Joyoshare Video Cutter. You can also refer to this guide, which tells you how to do it online: Trim videos by frames

For this you only need select the strip with the Right Mouse Button and press K to make cut where the cursor is positioned.

i'm sorry for asking, but how can i select the stream? I'm trying with [kbd]B[/kbd] then select the portion in the strip section, but it doesn't work

This doesn't delete the frames, stretching brings them back


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Merging model faces
Can anybody give me a hint whether it is possible to merge neighbouring faces of the model which edges are not straight?
I've made in photoscan 3d model of a few sculptures. Program is good but I wanted to add a base for it and refine it a bit in Blender.
Edges of the surface look more like a saw than a straight line, thereforeI'd like to ask whether ther is a possibility of merging faces extruded from such edges into one face (or at least smaller number of faces). If yes - how to do that?
This is how the edges are aligned:

I was going to clean it up and download on Sketchfab to give others chance to see it. This is purely for display - not for 3d print.
Thanks in advance!

Could you provide a screenshot?

As always, it depends entirely on the purpose of your model (still render, animation, 3D game asset, printing). So without knowing more, my answer would be "Well, yes - maybe, but no."

Pycoder - You can find the screenshot in the edited question.
Methapor - I am aware that it is not simple :) Thanks for pointing this down. To be more specific: model is going to be uploaded on Sketchfab. I do not have any plans to print it or use in a game. I am looking for a possibility to simplify and refine a model for more smooth display via web browsers

I would advise against merging selected faces on the screenshot as that would create an awful Ngon in the bottom of the mesh which might provide you with just unexpected surprises like unsupported Ngons for any other application or strange shading artifacts. There aren't that many faces at least compared with the print itself.


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UV Map Faces Unwrapping Out Of Order
I have an issue where my faces are unwrapping out of order (it would seem).
I've selected all my faces and unwrapped them, but there is ONE face that seems out of order during texture mapping.
You can see the circle that doesn't complete properly.
I have this issue often. Is there something I can do to sort the faces?

from what's visible, it seems that th rightmost "circled" face is overlapped to another one, maybe? because a slice of the blue circle seems to be missing, but could it be "covered" by that lst face?... difficult to say, only from the above images

Could it be the result of a boolean operation on a cylinder?

I don't know... it is really difficult from just those picture above. Could you pack the texture and upload it (or that part only) to http://blend-exchange.giantcowfilms.com/ then edit your Q and add the provided link, maybe?

you should be able to use the line select tool and scale up more so it covers the whole image, But Im not too shure :D

Scaling isn't the problem. Look at the circle and how it's mapping on the surface. It's missing a face on the right side. Not sure if it has to do with the "always selected" face during UV map editing. :(

oh I see are you able to scale forward or backwards to see if it helps?

Scaling just seems to move the error around as long as the Circle lands in the middle (where it needs to be). What's odd is that the mesh in the UV map looks perfect. As I select the faces in edit mode, the proper face selects in the UV map. I'm slightly confused, because I have the concave version on the other side, and it works perfectly.

yes I am slightly Confused too this is why I hate messing with UV's


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Some animations makes the model lean forward. sometimes almost 90 degrees on the X axis
I'm currently trying practicing animation and animating a very broken down model with separated parts like separate neck, head, fingers(except the feet) just to test out how to deal with that scenario. I just mentioned those because maybe it's necessary. So after I finished an animation, I cycle through them to look at the how I spaced out the keyframes most of the time. But sometimes, there's an animation that just messes up the whole model's rotation even when I made sure to put an initial keyframe for rotation and location for each movable part to prevent those scenarios. I nuked my animations multiple times already and it still happens for some reason, and it's quite annoying. I'll include the blend file so you guys inspect it. I guess you could already know which animation should not make the model rotate when you open the file. The "swordAction" animation rotates the model
I don't know how to include videos here, so here's a link

I can't see the armature rotating like you say, it will rotate if you give it the swordAction action, because this action is supposed to make the sword rotate, if you give it to the armature it will make the armature itself rotate like any kind of object. Is it your problem here? Because I can't see any keyframe that would affect the armature object itself in the other actions...

I don't know if it's an armature problem. Even when the sword wasn't there on my previous animations, some animation would just rotate the whole rig/model on a weird, unexplanable(for me at least) way.

Could you please share a video of your problem with the whole interface? I can't see it rotate with the current settings, unless I give it the swordAction action

Ok, I'll try to record one. That was what I meant. swordAction somehow rotates the whole thing even when there were intial keyframes for the other animations for rotation and location to prevent that scenario

Added a google drive link for the video

The action called swordAction is supposed to rotate the object to which it is assigned, if you assign it to the armature object, it will rotate this object. If you put another action above it in the NLA it may cancel this rotation, depending on this second action and depending on the strip settings

Yes as I say it rotates as soon as you give it swordAction, swordAction is not attached to an object in particular, it will act on the object to which you'll assign it, if this action consists on a rotation, it will make the armature rotate. If you then choose another action, if this new action has no rotation information, the armature object won't rotate back to a default rotation, it will keep the rotation inherited from the previous action.

Also you need to note that there are 2 sorts of keyframes for an armature: the keyframe that you can give in Object mode to your armature object itself, and the keyframes that you can give in Pose mode to its bones.

Ok, thanks for that info about the types of keyframe. I looked at object mode and there was rotation applied to swordAction somehow. That would be very helpful in the future for troubleshooting. Thanks man

Your armature rotates as soon as you give it swordAction, swordAction is not attached to an object in particular, it will act on the object to which you'll assign it, if this action consists on a rotation, it will make the armature rotate. If you then choose another action, if this new action has no rotation information, the armature object won't rotate back to a default rotation, it will keep the rotation inherited from the previous action (here, swordAction).
Also you need to note that there are 2 sorts of keyframes for an armature: the keyframe that you can give in Object mode to your armature object itself, and the keyframes that you can give in Pose mode to its bones.
I guess it's generally not recommended to give an object action to an armature, if you want to rotate the whole armature, rather parent it to an empty that will have the rotation action.


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What's the right setting for an array to fit a curve perfectly?
Even though I set the array modifier to fit curve and the object with the array modifier has it's origin on it's very center, it really doesn't fit quite perfectly. It either is too many or too few or just about perfect. I wonder if there is way to make it symmetric as well

hmm, I see. So just eyeball the offset get it to look right? Welp, if it's the only way

sorry my comment was wrong as Nathan said

To fit a curve without stretching, the array has to have the exact same length as the curve.  Here, our cube is 1 unit wide, but our unit-radius bezier circle has a circumference of about 2 times pi.  So there's no right number of cubes:

In order to perfectly match the circumference, we need to scale the mesh, which we could do to eye-- or, we could take advantage of a few curve settings to let Blender do this automatically for us:

By enabling stretch and bounds clamp on the curve, in properties/object data/shape, we're telling Blender that we want any curve deformed objects to start at the first control of the curve and stretch all the way around the curve to the final control (or back to the first control, for a cyclic curve like this.)
There are times when we don't quite want the whole curve, but we can still use stretch + bounds clamp, by creating stray vertices:

By creating a stray vertex (and, here, changing the array to a constant offset), it's a different bounding box that is being stretched to the curve, so we can use the position of that stray vertex to limit the end of the curve.  If we wanted, we could use another stray vertex on the other side of our cube to limit the start.
Stray vertices don't get rendered, but if you don't want them around, you can follow this up with a mask modifier to get rid of any stray vertices you're using to control the curve.

I didn't know about Stretch and Bounds Clamp, so thanks for that. Obviously, this is a much simpler/better answer than mine. I feel like your images might be a bit confusing due to the scale and distortion though, so I made this video to demonstrate the method with a setup more similar to OP's: https://i.imgur.com/H8VB62I.gif I was gonna edit your answer to add it but I wasn't sure about the etiquette. Cheers.

@Kuboå I'm sure there are some people who would rather not see their answers edited, so it's probably a good idea in general to ask, but personally, I'm grateful for any edits.  I figure it's all about getting good answers out there, and that works best as a team effort.

This is what I'm looking for. Thanks man

You can do this by using the Constant Offset mode of the Array modifier. To make the copies fit exactly, you need to know the exact distance there should be between them, and to know that, you need to know the exact length of your curve, which you would then simply divide by the number of gaps between the copies you want to have (i.e, 1 less than the copies).
First, to get the length of your curve, you can use the Curve Tools addon that comes with Blender. Once that's enabled in Preferences > Add-ons, select your curve, go to N > Edit > Curve Info and click "Length", which will populate the box to its right with the value. Copy this number (you can simply hover over the box and press Ctrl+C), then go to your Array modifier settings, click into the appropriate Distance box, and enter [YourCurveLength]/[NumberOfTotalCopies-1]. For example, if you have a curve with a length of 14 and you want 6 copies, you would enter 14/5.
This will also naturally result in a symmetrical setup.

Additionally, if you wanted to offset the position of the first and last copies of the array, you could switch to Fit Length instead of Fit Curve, then do the necessary math work inside the value boxes to accommodate the new situation. In the example below, I moved my mesh object +2m on the X axis as seen in the Item tab, so for Fit Length I subtracted twice that amount from the curve length to trim from both sides, and for Constant Offset, I did the same (in parentheses) before dividing by the gap number:

Could also be looking into using stretch+bounds clamp on your curve to auto-scale the array.

@Nathan oh you're right I didn't notice the stretch + bounds clamp

@Nathan I must admit I've never used those options, I don't know what they do. If you mean that's a simpler method, maybe you should post it as an answer?

@Kuboå I should, but I'm lazy right now.


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IK issue when hand is near face
I'm not entirely sure if I have a clear title but I provided some images to show what my current problem is.

Here's how the pose looks like. As you can see, the elbow is too high. I tried to move pole target to counter it, but it's not affecting it. What could be a good way to fix this?
I've added the file so you guys can check it if you want

The issue seems quite straight forward, the elbow needs to be fully open in order for the hand to reach that pose. The solution would be to either adapt your model and rig to the pose, or adapt the pose to the limita of your model and rig. The later is more often than not the most usited.in your case, i'd say a real human would not have his shoulders and spine square straight like you did, which is part if how we manage to do that when fencing.

Are you sure the hands are in the correct position? The hand palms of both hands point to the outside of the body.

@L0Lock I didn't quite get what you meant with square straight at first, which got me confused. That's something I didn't consider at first, the model was mostly for testing purposes so I just made it simple. Quite disappointing that I might have to change a pose that I thought was possible.

I mean that, the spine and shoulders poses are extremely straight and at square angles, that just not a pose that mechanically works with a human body. So unless you want to use wayarounds like stretching or dislocating limbs, you can't expect to make this work. Also check your limbs lenghts, it might be too short to being with, which doesn't help either.

@L0Lock oh, ok. I got that wrong again lol. I did move the shoulders as it looked weird that the arms were too close to the body. I just moved them to the side, of course, mirrored. I'll see if moving them in would fix it

I regenerated the rig from my backup metarig which I didn't move the shoulders and the issue is still there. I added a fresh metarig to double check and my shoulder position and limb lengths are the same as the fresh one

I think the problem is you are enabling IK_Stretch=1, allowing the armature (and mesh) to stretch beyond what it can attain. Try setting IK Stretch to 0:

and you'll see that your pose goal might be impossible for your armature -- is why the arm is straight and not bent, and the arm is actually stretched.

On the first rig I made, I did turn off IK Stretch. On the current one, turning it off still doesn't really give my expected result

It looks like you need to set the pole angle to either 90 or -90. I get this issue a lot on my models when the elbow poles aren't at -90 and also make sure your bones aren't completely level and straight or they will not bend and behave correctly.

I'm quite sure that I fixed the roll. Just checked it and corrected the rolls, still the same result

Nothing in the blender file, no objects in layers.

I just downloaded the file and it's exactly what I uploaded


text:
Copy Rotation not working, but was working initially

So I was making some changes to my rig, with some constraints applied to some bones. After regenerating it, for some reason, the constraint for curling the fingers stopped working. The screenshot I added is the constraint on the generated rig for the fingers. That constraint was already working before, and I didn't change it before regenerating. What could be the reason this thing stopped working?

It is because you regenerated the rig, replacing your generated rig and thus losing changes you had made to it.  If you need changes to persist through regeneration, you need to making edits to the metarig.  Presumably, this is Rigify (although it would be good to specify that in the question.)  You can see more details on how metarigs can be edited for Rigify at https://docs.blender.org/manual/en/latest/addons/rigging/rigify/metarigs.html .  In general, if you want to edit a rig to do exactly what you want, you probably don't want Rigify, you want to make your own rig.

Huh? What are you talking about? All the changes I made were applied to metarig before before I regenerated the rig. And I mentioned it worked before, right? I used the term rig because I would presume that that's immediately understood as relating to rigify by a blender forum. "Presumably. this is rigify"? Have you looked at the tags I used? And what's the use of rigify if it can't even handle a few additional constraints?


text:
Blender 2.8 DECALmachine PIL not installing on Windows
I've been trying to get PIL to install via the DECALmachine addon. I've ensured that my Python on my Windows machine is up to date: Python 3.8, PIP upgraded, PIL installed. I know that Blender uses its own Python.exe. Is there a way to get Blender to use my machine's Python? I haven't been able to find where the PIL DLL is install to attempt to move it inside the Blender bin folder.
I've ensured that all my Blender Foundation (and below) allow not only my user account by Admin account have total access via the Properties. I've run Blender in Admin mode and clicked the Admin options to install PIL inside the Addon DECAL interface, nothing turns the checkmark to green.
The first error I get is:
Ensurepip: C:\Program Files\Blender Foundation\Blender 2.82\2.82\python\lib\ensurepip False

I've confirmed this module is installed properly.
Has anyone else dealt with this?
Thank you in advance.

https://blender.stackexchange.com/search?q=%5Bpython%5D+system+python  If your blender and system python are same (x.y) to have 3rd party module available for both system and blender can pip3.8 install --user foo    To use system python can rename python folder in installation. (See other answers in search link above, for other methods that may suit)

Blender doesn't use your system's Python interpreter by default. That would require the use of --python-use-system-env in Blender 2.82 and later (see this answer for more information). Additionally your system's Python interpreter and modules would need to be compatible with the version Blender expects. Blender 2.82 use Python 3.7.4.
While it's unclear why DECALmachine fails to install Pillow, it shouldn't be necessary to use your system's Python interpreter. The script below will try to install the package and import the module.

Start Blender and open the Scripting workspace
Create a new text block (Text > New)
Copy and paste the script into the text editor
Open the console (Window > Toggle System Console)
Run the script and check the output of the console for errors.

import bpy
import os
import ensurepip
import subprocess

try:
    import PIL
except ImportError:
    # The import failed, therefore we check that pip is available and attempt to install the package.

    # ensurepip.bootstrap() also calls pip, which adds the environment variable PIP_REQ_TRACKER. After
    # ensurepip.bootstrap() finishes execution, the directory doesn't exist anymore. However, when subprocess
    # is used to call pip, in order to install a package, the environment variables still contain
    # PIP_REQ_TRACKER with the now nonexistent path. This is a problem since pip checks if PIP_REQ_TRACKER is
    # set and if it is, attempts to use it as temp directory. This would result in an error because the
    # directory couldn't be found. Therefore, PIP_REQ_TRACKER needs to be removed from os.environ.
    ensurepip.bootstrap()
    os.environ.pop("PIP_REQ_TRACKER", None)

    # Try to install the package. This may fail with subprocess.CalledProcessError
    subprocess.run([bpy.app.binary_path_python, "-m", "pip", "install", "Pillow"], check=True)
    import PIL

print(PIL.__version__)

A more generic version that allows install packages in a simple way:
import bpy

def ensure_and_import_module(module_name, package_name=None, global_name=None):
    """
    Ensures that the required package is installed and imports the module. It will attempt to install the package
    through pip if the import of the module fails.
    :param module_name: Module to import.
    :param package_name: (Optional) Name of the package that needs to be installed. If None it is assumed to be equal
       to the module_name.
    :param global_name: (Optional) Name under which the module is imported. If None the module_name will be used.
       This allows to import under a different name with the same effect as e.g. "import numpy as np" where "np" is
       the global_name under which the module can be accessed.
    :raises: subprocess.CalledProcessError and ImportError
    """
    import os
    import sys
    import importlib
    import ensurepip
    import subprocess

    if package_name is None:
        package_name = module_name

    if global_name is None:
        global_name = module_name

    try:
        # Attempt to import the module and assign it to globals dictionary. This allow to access the module under
        # the given name, just like the regular import would.
        globals()[global_name] = importlib.import_module(module_name)
    except ImportError:
        # The import failed, therefore we check that pip is available and attempt to install the package.

        # ensurepip.bootstrap() also calls pip, which adds the environment variable PIP_REQ_TRACKER. After
        # ensurepip.bootstrap() finishes execution, the directory doesn't exist anymore. However, when subprocess
        # is used to call pip, in order to install a package, the environment variables still contain
        # PIP_REQ_TRACKER with the now nonexistent path. This is a problem since pip checks if PIP_REQ_TRACKER is
        # set and if it is, attempts to use it as temp directory. This would result in an error because the
        # directory couldn't be found. Therefore, PIP_REQ_TRACKER needs to be removed from os.environ.

        ensurepip.bootstrap()
        os.environ.pop("PIP_REQ_TRACKER", None)

        # Try to install the package. This may fail with subprocess.CalledProcessError
        subprocess.run([bpy.app.binary_path_python, "-m", "pip", "install", package_name], check=True)

        # The installation succeeded, attempt to import the module again
        globals()[global_name] = importlib.import_module(module_name)

# Make sure that Pillow is installed and PIL can be imported
ensure_and_import_module("PIL", "Pillow")
print(PIL.__version__)

Thank you very much for the script. It failed on "import ensurepip" however from the terminal, it says that it's already installed when running from python.exe within the bin directory.

@DrTyrell What command are you running in the terminal to check this? Apparently you have broken something in your Blender/Blender's Python installation if ensurepip can't be imported.

Will it break everything if I'm running purely Python 3.8?

@DrTyrell I haven't tested it, but I would assume that there could be some incompatibilities. Since it would be a guessing game to figure out how/what exactly broke your install, please uninstall Blender 2.82 and delete C:\Users\[insert username here]\AppData\Roaming\Blender Foundation\Blender\2.82. This will completely remove all preferences/keymaps/add-ons. Install the most recent stable version of Blender. Don't mess with the file/directory permissions and use the Python interpreter that is included in Blender.

I switched back to 3.7.4 and ran everything from an Admin level account for install, and it worked. One does have to manually update pip and ensurepip, then run Blender from Admin permission, pressed the Install PIL Admin and it BING it worked. Then restarted Blender and we're good to go. Thank you again!

@DrTyrell No problem. BTW you can avoid using admin privileges for pip by using the portable version which you can place in any location. This avoids the issue with pip trying to add files in C:\Program Files\ which requires admin permissions.

Ok, crazy. After getting it to install correctly it told me to restart Blender. After restarting, it needs to be installed again. It installs every time now but after restart, it's missing it. I've confirmed every module is satisfied in both local Blender bin and in the global location, but it continues to fail. Boo.Your script above fails on "ensurepip" as if that's not installed.

Let us continue this discussion in chat.


text:
Network Render Errno 2: No Such File or Directory
FIRST:
I'm on a Mac. I'm running 2.78.
SECOND:
Got the Network Rendering setup perfectly. I've sent jobs over my network. Once a job chunk is processed, the job fails due to Errno 2, No such file or directory [insert job directory file here].
ATTEMPTS TO SOLVE:

Initially used /tmp/
Switched to a directory I made on my Desktop
Gave R/W permissions to ALL groups including "Everybody"
Ran Blender from the command line in SUDO mode

WHAT HAPPENS:
The files are created on the Slave machine, but it throws an Errno 2 upon finishing a chunk. It looks like it's trying to access the EXR file to send it back to the Master.
I own several computers, and all of them are failing in exactly the same way.
Suggestions?

https://www.youtube.com/watch?v=y3EcpkwLCFI This is Moby Motion showing how to do this and he made key point about UNCLICK Overwrite and Click on Placeholder because this keeps track of what each machine has done. The tutorial is 9 minutes and wow cool

authors: Діана Бурковська


text:
How to get HDRI Environmental Maps to light a scene?
I'm using HDRI's in Blender 2.8 (cycles) and I don't understand how these are supposed to work to create realistic environmental light. The BLUE in the "Sky" shots is casting so much BLUE that my entire world looks ridiculous.
Is there a way to use JUST the sunlight within the HDRI to create more realistic sunlight?
UPDATE: I think the trick is to ensure that the trees or mid-point of the HDRI is exposed as to cut down on the sheer amount of blue influencing the rendering. This version looks acceptable to me.

Without seeing the HDRI or your scene all we can do is guess. Many people have used many HDRIs to make many very realistic scenes, so... As to your bolded question - if you want no blue from the HDRI, use a sun lamp instead with nothing for the background.

http://blog.gregzaal.com/2013/07/24/cif-2-hdr-lighting/ in this nodetree you can add RGB curves to adjust a color Tint.


text:
How does one create a particle cloud that collides like real smoke?
I'm familiar with all the volumetric methods of creating cloud looking things. I'm familiar with particles from emitters.
What I really need is a cloud of smoke that moves like real smoke when an object moves through it.
I was thinking it could be done with particles emitted using zero gravity, then set a collision on them and move them when hit by an object, but I'm not sure how to set that up.
This is a very quick two second scene requirement, so I can use millions of particles if necessary.
The end effect would be like a person walking through a cloud and disturbing each particle of smoke.

Thank you for your thoughts.

Why don't use smoke sim directly? If you really need particles, you can use smoke sim as force field for particle system. One thing that I'm not sure about in Blender, if there was some progress in collision, because when I tried wind tunnel last time, there wasn't any vorticity behind the collider.

The problem is that Blender emulates smoke using a volume shape. It doesn't actually have individual particles that collide with an obstacle. To my knowledge.

@DrTyrell: This isn't totally true - but in parts. The smoke itself does not react to collision (unfortunately) but if you are using particle created smoke and collision objects, of course the so created smoke does "kind of" react with the collision, but only as the particles do. So later on, if e.g. the smoke would be moved by wind/gravity - it would go through the collision objects [1]: https://i.sstatic.net/XiljB.png

I was thinking I could create a volume that distorts in shape to simulate the collision.

i am also not very experienced with smoke, but i would force fields parented to your object give a try. This might help and give that illusion.

Here is what I meant by Smoke as force field for particles and here what is wrong with turbulence seen in the first anim. ...

We should probably ask - What did you try and where did you fail ... :)

Smoke Simulation
Like in my comment simple smoke sim seems to handle your needs ...

Vector visualisation ...

Here is a slice on Y axis where you can see what I mean by  -no backflip turbulences ... smoke reacts on collider movement but not exactly as in a real world ... part of vorticity is missing ... but like I mentioned for your purpose it could work ...

... or you can add another Force Field parented to Collider (mentioned by Chris if I understood it right :) )
So I have to ask again - What is the specific reason you need particles.
Probably add some more screens or mockups to express better what didn't wok for you and what specific effect do you expect. Thank you
Smoke Simulation used for Force Field > Fluid Flow
Here is example with Particle system driven by Fluid Flow Force Field issuing smoke sim ...

Such nice visualizations!  I'm going to have to post a Q asking how you did those, unless you stop me because it's too 'obvious'.. :)

... all is under Smoke Domain > Fluid Properties > Viewport Display :)

likewise! I don't know why our paths haven't crossed, recently :)

Incredible. Thank you! My need is to show a close up of a vehicle push through fog just as you have it. The effect is important to the director if you know what I mean. ;)

Great if you found it useful ... Good luck with your project


text:
How to keep or transfer edge attributes after using Mesh To Curve Node?
I have a problem with a node setup that converts the imported mesh to N-gons mesh (I use this to clean up the imported mesh for the next instancing module nodes).
And the integer attributes assigned to the edges are removed after using the Mesh To Curve Node.
As you can see in the screenshot below, 3 attributes: blank, door, and balcony were assigned to some edges.

This happens after using the node setup. The attributes were removed.

I tried to capture these attributes the way I did with the Position attribute but it did not work, maybe I missed something.

How can we keep these assigned attributes while keeping my node setup?
See my nodes in the following file.

I think edge attributes are lost by Mesh to Curve node. Could you try and capture in Point domain before this node ? An other way could be to Sample Nearest edges after the Fill Curve nodes with target the Group Input Geometry.

This is not too simple, but a few hints: the attributes are kept in the point domain (but that means they will be interpolated and will probably be messy). You can use the final edge positions to "sample nearest" edge of the original geometry. The drawback here is that the final geometry doesn't seem to follow the original and some weird results appear. You could also try to resample the curves in small segments to use the point domain in a better way (just use float instead of boolean, then you will have interpolations that make sense or are wrong only at corners.

I do not understand why the "Fill Curve Keep Position" frame, but is there any reason not to simply proceed like this: https://i.sstatic.net/eArFu1ov.png ?

The frame [Fill Curve Keep Position] is used to fill any closed curve, preventing the flattening of curves on the plan, unlike the way the node [Fill Curve] operates.
Your node works fine. Thank you, @SteftAncien.

Anything against just deleting the inner edges without all those weird set positions?
Anyway, the solution is "store the attribute" again sampling from edge position to nearest edge.

It works! Thank you, @Daniel Moller.


text:
Locally rotate bone in IK chain without affecting other bones
I have a long snakelike cylinder with 5 bones in it, attached to an IK control bone, to make it slither.

Now I want the IK target bone (the one that has the IK constraint modifier), to rotate locally (roll around it's y axis), without affecting other bones in the chain.
This is not working: The other bones slightly move, too.

How can I have one bone roll, without affecting other bones?
These are the constraint settings:

I am rotating with R + y in local transformation orientation.

In this gif you made doesn't seems like the other are also rotating. Can't you do this rig with Spline-IK rather?

@AAAYerus they're not rotating but they sure are moving.

Depending on the needs, it's better to do with Ik-spline, it's more precise.


text:
Instancing faces as objects
I am trying to make a procedural cave system. I have created 5 different walls and I want to instance them on the faces of the white object named as "Cave" (Check outliner).
I have applied rotations and scales of walls.
I made sure all the walls z-axis look the same direction which is world space z-axis.

I have tried a simple GeoNode (got instructions from reddit and chatgpt, I am not much familiar with GeoNodes). 2nd picture is the result of the GeoNodes.

If I could describe what I am trying to do properly, could you help me?

Yes, you have instanced your objects on the faces. What exactly is your problem?

"If I could describe what I am trying to do properly, could you help me?" - it depends how you ask your question. You can read this post that explains how to ask a good question on BSE.

A naive solution: click "reset children" in the collection info, and plug a "normal" node to the "vector" input of align rotation to vector

This is the answer to the question being asked.  However, if I were trying to guess what OP is trying to do, it is stack all the rocks in the form of whatever tunnel he creates.

Your objects are not rotating correctly for a couple reasons.
Applying scales/transforms is a good step.  To make sure your objects' origins are correct, you can select them and use (f3 to search) Origin to Geometry.
Separate and Reset Children can both be checked if you don't want the instanced objects to move when you move the corresponding collection info objects.
Adding a Normal Node to the align rotation can help to rotate instances correctly.
In the image below all instances are basically walls of the default cube with noise textures:

If this solution still doesn't work for you, and you are more interested in stacking all these irregularly shaped rocks, you can try this node tree.
The process is described in a video called Turning ANYTHING into Rocks - Blender Geometry Nodes.  Here is the procedure:
a)first break the imported object into a series of a more or less hexagonal grid cells but randomize the generation(, Triangulate, Dual Mesh)
b)splits their edges somewhat Randomly,(Random Value, Split Edges)
c)give them subdivisions to round them,(Subdivision Surface)
d)add noise to them and extrude them. (Noise Texture, Extrude)
The result is quite different and does not even use instances, but creates procedurally generated geometry per face, the advantage being, we can create a bunch of stacked stones that are all irregular shapes.

To add more randomness to the shapes:


text:
DXF line layer not rendering in Freestyle SVG Export
I'm working on a project in Blender 4.1 where I need to export lines as a SVG for use with my plotter. I am using Freestyle SVG Export.  I've imported a DXF file from QGIS, which contains line geometry, into Blender. The lines look fine in the viewport but are not visable in the camera view when rendered and do not export as a SVG. I have tried adding a skin, this makes the skin appear in the camera view but it is not exported as svg. Also i have pressed E in Edit mode and did some weird sliding thing and this also does not appear in the SVG. As well, i tried the wireframe modifier, however it appears to do nothing at all.
I have tested Freestyle SVG and it works when i create simple shapes in Blender but not when I import lines from a DXF file. The lines are very simple it should not take long to export. I have a super fast computer, total overkill, so its not that either.
Does anybody have any suggestions or ideas?


text:
How to drive shape keys based on the angle between two bones?
My character rig needs shape key correctives when it makes certain poses (eg. lifting the arms, the shoulders need to be corrected with a shape key so they don't lose volume).
I know you use a driver for that, but the way I find it in books and tutorials is to use a "Rotational Difference" driver between two bones (like between an arm bone and a reference bone pointing in the direction that should activate the shape key, so the driver is 1.0 - rotDifference), and use that driver on the shape key. Like this:

The problem is that this driver doesn't work well for this, because when the bones roll around their aim vectors (without changing their actual directions), it still triggers the shape key:

How else can I activate shape key correctives based on the rotation between two bones (and only their directions)?

This answer was written for Blender 2.79 and 2.80. The latest versions of Blender from 2.82 and above (like 3.0, 4.0 etc) have a "Swing" driver type that can be used for this: https://docs.blender.org/manual/en/latest/animation/drivers/drivers_panel.html#rotation-channel-modes
So the original text below is obsolete as it was written before this new driver mode existed. It's kept for historical purposes anyway.
Original answer:

For an ultra-fast driver for corrective shape keys based on the angle between two bones, you can use this one:

The driver type is Scripted Expression, with this line (depending on your Blender version):
Blender 2.7x:
poseBones[A].matrix.col[1] * poseBones[B].matrix.col[1]

Blender 2.8x:
(Same line as above, but replace * with @)

(In order for this expression to work you need to enable the Auto Run Python Scripts setting in Blender. On 2.80 it's in Preferences -> Save & Load -> Auto Run Python Scripts and on 2.79 it's in User Preferences -> File -> Auto Run Python Scripts.)
This expression uses the dot product of the bones' aim vectors, a mechanism known as a "pose reader", used with pose space deformation (PSD).
As the bones rotate during animation or posing, the driver will output a value in the range [-1, +1], going from -1 when the bones point in opposite directions, up to 0 when they become perpendicular, up to +1 when they point in the same direction.
Replace A and B in that expression with the indices of the two bones involved. The indices are from the bones list of the armature, and the only way to find them is by using Python. But it's simple:

Select your armature object;
Change the editor to Python Console;
Type the next line in the console and hit Enter:

C.object.pose.bones.find("My Bone")

Instead of "My Bone", use the name of the bone whose index you want to find, then press Enter to see the result. Do this once for each bone so you'll have two numbers, like 12 and 103 for example. Put them in the expression (in any order), inside the poseBones brackets:
poseBones[103].matrix.col[1] * poseBones[12].matrix.col[1]

Next, the other driver variables are:

A Single Property type variable named 'poseBones', used in that expression. The ID type is set to Object, and the object itself is the armature that has the two bones involved. The actual path to the property in the object is pose.bones, write this in that field. See more details in the Notes section below.

(Blender 2.79 only, not needed for 2.80+):
A dummy Transform Channel type variable, it needs to point to any bone in that armature (any indeed, like the root bone). This variable is unused but is an essential piece, it's a way to force Blender 2.79 to evaluate the driver every time a bone in your armature moves from animation or posing.  Set the channel type and space to Location X and World Space, respectively, which makes this very fast to evaluate.
Again, this variable is not used in the expression and is only needed when on Blender 2.7x.

Your driver is ready to be used, with no roll changes or sudden flips.

Notes:

The two bones used in the expression should not be animated in scale (be it their own or inherited scale from their parents), they should only be animated in position and rotation. This means that they need to have a scale of exactly 1 in all axes, for the entire animation, otherwise this will mess with the speed of the driver because it affects the length of the matrix.col[1] vector.
If you need to animate them in scale, simply add a child bone to them and animate the scale of the child and deform the mesh with that child bone, not the parent.
You can adjust the timing and speed of this driver by playing with the driver graph curve, like using easing or bezier handles.
For example, when used with shape keys, you can make the graph minimum be zero and maximum be 1 (click to enlarge):

The natural rate of change of this driver is senoidal because of the dot product that it uses in the expression. If you happen to need linear speed, adjust the bézier handles of the curve in this way to keep the rate of change constant (click to enlarge):

The poseBones variable in the driver is referencing the .pose.bones property of the armature object (like bpy.data.objects("Armature")) and not the armature data (like bpy.data.armatures("Armature")). That .pose property exists in objects only.

This answer is amazing. It just so happens to be exactly what I need right now. Thanks for posting.

Is there some reason you're also using a "dummy" variable in your screenshot of the driver editor?

@Nathan that dummy variable is the one described in the "Next, the other driver variables are:" section. It's only needed on Blender 2.79, so if you're using 2.8x that dummy variable can be ignored, as the driver already updates whenever any bone in your armature moves (I'm guessing from improvements done to Blender's depsgraph).

@R.Navega Thanks, my bad, didn't read closely enough.

You should accept your own answer ;-)

@BrunoBieri thanks for the tip! By now it seems the new driver Swing & Twist modes (since Blender 2.82, devnotes in here) can be used for that, I haven't experimented with them, though. See Swing and X \ Y \ Z Twist in the manual.


text:
Where are these 'flares' coming from? New User

I'm getting these 'flares', for lack of a better word, appearing all over my camera viewport and rendered animation. They come in just about every colour you can imagine and I can't for the life of me figure out what's generating them. Using Eevee if that helps.
If anyone has any suggestions then help would be greatly appreciated! I'm quite new to Blender and am working through the terminology.
As I'm not sure where they're coming from I'm not really sure what information to include in this post so I'm sorry if it's:
a) a super simple answer or
b) an incredibly vague problem
Thanks in advance!

Would you mind uploading the blendfile to https://blend-exchange.giantcowfilms.com/? It's kinda hard to find the issue from the image alone

@haarigertroll
Thanks for replying! Here's the link:

Last night I changed the tile size from 2px to 4px in the volumetrics for a cube that the scene sits in and haven't checked to see if that changed anything yet this morning

BUG report https://developer.blender.org/T77202 Related https://blender.stackexchange.com/questions/167395 https://blender.stackexchange.com/questions/163706 https://blender.stackexchange.com/questions/192735


text:
Water simulation hangs over the surface of the collision object
I created a water particles but they seems to hang over the surface, why is this happening?

Still the water hangs over the ground even with Collision Surface Thickness zero:

could you upload a link to your file so I can take a closer look?  you can use this link: https://blend-exchange.giantcowfilms.com/

check the "Thickness" of the Effector -> Collision objects.  Set them to 0 or 0.001, as that is the distance BEYOND the mesh that effects the liquid

Your domain is too big, scale it down as much as possible to just cover expected simulation range in a scene. Something like this ...

You use a lot of colliders with very chaotic topology. I would suggest to use one simple that would be faster in simulation and it prevent from leaking water. Bake simulation and for rendering disable this simple collider in Outliner.
In this example I used a subdivided Plane  with Shrink Wrap modifier > Projection > Z to quickly recreate your colliders.

Increase value for "Resolution Divisions" that is too low. 64 is not enough to generate a grid dense enough to bring water closer to collision objects. One division is represented as a cube in domain corner. Amount of divisions is always a longest side of domain divided by this number.
This is your current Domain with Res.Div. 64

My Domain scaled down with Res.Div. 64

My Domain scaled down with Res.Div. 128

My Domain scaled down with Res.Div. 256

So as you can see each time the Resolution Division is increased, simulation is closer to collider thanks to detailed grid (division) of domain.

Here is a fluid simulation with a liquid Effector Collision Thickness of 3 vs a Thickness of 0

and here is a domain where collision distance is too large and particle radius is rather large (2.0):

In other words, try dropping your collision thickness to '0' and particle radius to < 1.0.

Karol react to your suggestion by "I tried everything you said, but it didn't work. How can I get over with this? I drop the thickness to 0, then to 0.000001 and nothing...". His post was hidden because was written as answer and not as a comment.

@vklidu Try a thickness of at least 0.4 or 0.5.

Karol (author of OP) was asking ... not me :)


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Assign metaballs to trails form a particle system
currently switching from C4d to Blender, I try to reproduce some classic motion graphic effects in blender.

To illustrate my question, here's a link to watch (6min 45s): https://mattrunks.com/fr/formations/cinema-4d/eclaboussures-2d-x-particles
I am stuck when I want to assign metaballs to my trails. I could render my particles as object with a meta ball as reference, but the look will be some spheres and I want more a stroke look. Like this ...

Is there a way to achieve this?

https://blender.stackexchange.com/questions/194011/is-there-any-technique-to-give-a-metaball-effect-to-the-particles-emitting-from/194013#194013

Use type Capsule instead of Ball ... There you can specify length ... https://docs.blender.org/manual/en/latest/modeling/metas/structure.html

Thanks guys, great example from Duarte Farrajota Ramos, looks like I missed this capsule...

If you will be able to reproduce this effect by this way, please create answer, I m interested :) I'm quite skeptic about using meta object, since they have very low connectivity for such "elastic" effect presented in video. ... and please next time attach some screenshots instead of external links that are not permanent (this site is meant to be a knowledge base). Thank you

Yes you're right, I am not able to reproduce this elastic effect with the meta balls. Maybe I will check later with a cloth object, since I am new to Blender, I don't know if this approach would make sense. (Got it for the screen shot)

In particle system you have render, select object and now your trail is rendering a specific object that you select

I didn t notice you could replace the trails by an object after caching them, thank you!


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I'm having problems while unwrapping uv's from some meshes I have
They will either not update or become a mess if I reset them before. I'm using correct seams, I have tried appending the meshes to a new file, I've even sent the file to another PC wondering it could be a bug with my blender, but none has worked. I think it maybe has to do with my file settings, but only the meshes seem to fail, while not having overlapped topology or any other common problems. It happens with all of the separate meshes oxcept for the pigtail for some strange reason. I've also applied all transforms to all of them.

Have you tried applying the mirror modifier?

@BK.yep, and other modifiers and still the same problem

@vklidu sure, I kind of worked around it with a lightmap, which for some reason was the only way it unwrapped decently, but it comes with the problems you would expect from a lightmap (texture bleeding so I need a bigger texture, among others).
At this point I really want to know why it happened, because I wouldn't want it again, plus I just followed my usual workflow which hasn't caused me any problems.

Btw, I'm trying to texture paint, and only the geometry that wouldn't unwrapp correctly paints as if I had an airbrush with texture, which is kind of annoying, but not a mayor problem, I'm just wondering if there is any kind of relation there

Those mentioned parts of UV are Pinned.
(vertices marked red)

Press Alt+P to Unpin and Unwrap U again :)


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Thumb moved on it's own when I didn't animate it
I don't know what is happening to my rig, because for some reason, the right thumb moved on it's own only on the last (for now) animation I was working on. I already finished a couple of animations and this is the only time I got this weird issue. Here's what the thumb looks like on the current animation I'm working on:

It seems to be just going down. I don't think it's following the right foot because on the animation I was doing some sort of stomping motion on the right foot, and when the right foot was raised, the right thumb was already almost at the bottom of right hand. It looks like this.

remove the thumb from all vertex groups and reassign to the correct vertex group?

From the screenshots, it is unclear whether this is a rig issue or a skinning issue. Can you verify that the bones are behaving as expected, and that it is just the skinned mesh that's deforming unexpectedly? It will speed things up if you can share the file.

It seems like the thumb bones on the animation is moving on it's own. I added the file so you can check it. The specific animation that is having the issue is called "rig_ox_summon_wall"

You've keyframed location onto thumb.01_master.R .  So, your thumb moves.  To fix, delete the keyframes on this bone (they don't do anything else.)

Oh, I didn't know that thing moved. Thanks a lot, man.

The bone "thumb.01_master.R" has wrong key-frames.
Look at the picture below :

Yeah, a guy commented about that above. Thanks anyway


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How to animate a rig and props simultaneously for Unity?
I was trying to animate a character rig with a prop and got some unexpected result. The reason why I'm animating a separate prop is because what I have in mind is, in Unity, I'll turn off the prop's MeshRenderer and I'll parent whatever "real" prop that I need on that props position. Now, the animations for the rig was exported properly, with a bit of issue. But the props animation somehow got applied to the rig as well. On one of the rig's animation, the left arm did some weird thing and it didn't follow the hand properly.
I'll add my blend file here as I think it might be easier if you guys can see it yourself.

This is what the model looks in blender.

Here's what it looks like in Unity(the other side is alright)

And here's what the animation of the prop looked like in Unity

I've already seen this as well and I'm not quite satisfied with it's answer
UPDATE:
I kinda found a workaround for that prop animation affecting the rig. What I did is I just gave the prop it's own bone so the the animation the prop needs only applies to it's own bone. Unfortunately, that weird exported forearm behavior is still there.
UPDATE:
Here's what the model's hierarchy on Unity, I already made the model humanoid:

UPDATE:
After following the answer below, I realized that my model can't be recognized as humanoid because Unity can't find a head bone. I think I kinda have this problem before as well

Are you treating the skeleton as a Humanoid skeleton or a Generic skeleton in Unity? Can you show the bone/game object hierarchy that gets generated? Just drag the character into an empty scene, and expand its hierarchy.

Hi, sorry for the late reply. I already added a screenshot of the game object hierarchy of the model.

Can you try to make the sword bone a child of the hand bone and test if it makes a difference? For some reason, the MCH bones are getting exported as well. Can you select Only Deform Bone when exporting?

Will try later. But I didn't have that sword bone before and the main rig still have that arm issue

Yes, but when you didn't, you still had the object there which caused a bigger issue. As far as I know, Humanoid skeletons have strict requirements. Having additional bone hierarchies and extra objects just confuses the automatic process of bone mapping. That's why I am giving you suggestions to remove as many of the extra stuff as possible to make the automatic process figure out the correct mapping without manual intervention.

Just out of curiosity, did you try the Generic skeleton?

I downloaded your file, cleaned up a few things, and exported the bare minimum to an FBX file (no weapon is included). I uploaded it to WeTransfer here. It imports fine in Blender on my side. Can you verify that it imports fine on your side in Blender and in Unity? If it works, I will write an answer with the steps I followed.

Oops, I forgot about this. Will try later, I'll surely be able to check this out as I'll have more free time later this evening

Hi @MrA, I just tried your fbx file and it fixed the arm issue, but has the main model floating issue on the sword_pos animations

I inspected the FBX file, and it seems that there were indeed more animations in the file. This probably confused Unity once again. I most likely forgot to uncheck some boxes when exporting the FBX file. Anyway, I think I have all the information I need to write an answer. I will do it now.

The way that I've done this previously was to add an extra bone to the deform skeleton for the prop. Since you're using Rigify, this kind of edits will be overwritten if you regenerate the rig. That's why I suggest to do this when you are sure you won't need to regenerate the rig.
The bone you add should preferably be a child of the hand that holds the prop; however, if the prop is expected to switch hands or be mounted on the torso or back, it may be better to make it a child of the root bone. While animating, you can parent it with constraints to whichever bone makes sense depending on what you want to achieve.
The prop mesh you use in Blender will be parented to the bone just to help you visualize the bone's movement, but you won't need to export it, and you won't animate it. You will animate its bone as part of the character rig. In Unity, the animation of the bone prop may get discarded, because no mesh is skinned to it. However, I believe there is an import setting to change this behavior.
Your new mesh in Unity should be instantiated as a child under the prop bone. Make sure to pick a good default position and orientation for the prop bone to eliminate the need to adjust the position and orientation of weapon in Unity after instantiating it under the prop bone.
Your file came with a number of animations. Depending on your FBX export settings, this can lead to issues. I suggest to uncheck NLA Strips and All Actions. Since your file has many objects, I would also limit the export to Selected Objects only which will be the rig and the character only (no prop mesh as mentioned above). A screenshot is attached below.

I believe the right arm bug was caused by a parenting issue in the bones. In my test, I baked the animation on the deform bones clearing the constraints. Then, I fixed the relationships between the bones to make the rig have a clear hierarchy. I also deleted all bones except the deform bones. The deform bones are on the third layer from the bottom right (layer 29 where the first layer is layer 0).
I am sorry if this is too much to take. Skinned assets are the hardest and trying to add complexity on top of this makes a complex mess.

Ok, that only deform bones fixed the issue I think, and not including the props as well. And maybe 4.0?

I am not sure if you mean swords in two hands or a sword that is held by two hands. For the first, you will need an extra bone on both hands. The sword in the right hand will be attached to the extra bone in the right hand. The sword in the left hand will be attached to the extra bone in the left hand. Everything else will be the same. For the second, the original setup will work fine as the weapon will follow one hand. When animating, you will typically add a constraint to parent the other hand to the weapon after placing it where you want on the weapon.

Just did some additional testing and I think your proposed process made the head disappear so Unity can't recognize the model as humanoid. I'm thinking that maybe I'll just do some ugly stuff on Unity to "animate" the swords and stuff by adding an empty GameObject to the chars hands, parenting the weapons there and coding it's rotation if needed

All the bone fields are filled in. I can't see the problem.

Except for the head unfortunately, because if you look at the other screenshot, ORG-spine003 doesn't have any other child bone left except the left/right shoulders

I see. This is sadly an artifact of how Rigify does parenting for the bones. That's why you ended up with so many MCH bones in your export. In my manual clean-up, I remove those bones and re-establish the deform bone hierarchy to be something that Unity can easily pick up. Honestly, when I use Rigify, I don't use its deform skeleton directly. Instead, I attach my character's skeleton to it using constraints. It an extra step that saves me so much headache in the long run.

Let us continue this discussion in chat.


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Another boolean modifier problem

Blender 2.78. i have a model that as best i can tell has all of these for every object on every layer:

all normals correct
no doubles
no internal faces
no loose geometry
fully manifold

the three cutouts for objects are to be applied using boolean ops to carve away affected geometry; lift guide, glue plugs, and lift nuts. the first two apply properly. when the boolean op for lift nuts is added, the window clip disappears.
i've browsed page after page of boolean op problems here and elsewhere and gone over my model intently. i don't think i've missed something so then i'm left considering that i'm naive to some aspect of this.

You using n-gons extensively. I would always expect problems with trying to use booleans with them.

Blender's Boolean Modifier sometimes seems to work completely random. This is mostly the case when you have objects that are a little more complex than basic shapes like cubes, cylinders and the like.
In this cases it's helpful to show the modifier exactly what you want by creating overlapping parts. Just pull the lower vertices of the lift nuts down a little so they clearly overlap the window clip.

awesome, this was perfect. i'll have to remember this as i haven't encountered this problem before

From my experience it seams, that when using boolean you should always make ends of hole cutting mesh, stick out of the mesh, that is being cut. So in this instance you have to go to edit mod and raise up top vertices of bolts, above surface of window clip and lower bottom vertices of bolts below surface of window clip. This will solve the problem.
p.s.
By bolts I mean cutouts, lift nuts and cutouts, glue plugs

ah, a very helpful hint to have. i'll mentally bookmark this to check when my boolean fails next time. thank you


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Object disappears in game engine
I am working in the game engine. I have tracked camera to follow the ball. When I play the animation, ball appears for half the time and then it disappears. Also the colors in the background do not appear. Only black color appears.
Also when I start it in game logic and start the standalone player, nothing is displayed. Please help me.
How can I share my .blend file here?
Its kind of urgent... please

I've removed the animation. Can someone tell me why do the colors disappear?

You can upload your file to Blend- Exchange and edit the resulting link into your question.

The file is quite large... 111MB...

A ball with a ground should be less then 1MB. Better prepare a simple demo file. We really do not want the other things. [edit] there are 13Mb of data. How to use this file?


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Problems With Incredibly Noisy Renders In Cycles
I'm attempting to create a space station hallway in blender Cycles as concept art for a game.  After modeling the entire station, I decided to do some simple test renders to see how the lighting would work through the window opening out to open space.  After tweaking the material to make a better window, I started rendering it out with a sun and very few inner materials (I don't apply materials until I really get the lighting down).  After doing this, I came up with this render on 500 samples:

Essentially the entire thing is incredibly noisy.  While I know that this question has been asked before I couldn't find anything that would help it.
How can I make this less noisy? I've tried a lot, and it just stays bad.  Any help is appreciated.
Here's the blender file:

Testing without materials attached may not be giving me the same results as you, but I have modified a couple of settings to generate this render:

I have increased your sun lighting somewhat and I added a spacey HDRI image as background, mostly so I could see what was going on inside the station. I then added a slight amount of clamping to direct and indirect. That render is at .10 and .05 respectively, I think. Smaller clamp amounts may have worked.... depends upon what you are going for.
HDRI from Blender Guru Pro Skies, not my work.
If this is moving in the direction you intend, I think some combination of clamping direct/indirect and working with the light paths -- https://www.blender.org/manual/render/cycles/optimizations/reducing_noise.html -- may get you where you want to go....
EDIT=====================
Sorry. I deleted your original file, so I downloaded again and made changes only to sun power settings and clamping to produce this:

I did not pack the space HDRI into the new blend file, as I believe it is copyright by Andrew Price in his Pro Skies.... so the second render was made without an HDRI in place.  Here's the modified file:

And just FYI: https://www.blendernation.com/2017/01/21/creating-looping-corridor/

I'm sorry but i'm pretty bad at blender.  If you could potentially share the blender file so that I can look at it and learn for myself, that would be immeasurably helpful.  If not then I'll just scrutinize it as much as i can.

Alright that solved my issue.  Thanks for the help!


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Trouble locking an object to an axis while moving them!
Using either the G-- x,y,z or even the gimbal, the object seems to jump out of alignment along one of the other axis.
For example, trying out Blender Guru tutorials, trying to move a circle vertically down, I would press G, then the axis to lock... but the circle seems to "jump off the rails" so to speak... and seems to come closer to me.
Even in a pure side view where it appears to only move vertically, soon as you swing into a 3d view... it has mysteriously moved out of the axis I was trying to move it along.
I'm not using the move excluding a certain axis, and I've played with the various orientation controls in the move menu.. I'm stumped.. and unable to move any precisely!

you say that the object jumps, which looks like you've enabled the snap option, then what you say doesn't fit that explanation... maybe share your file? (keep only one object) https://blend-exchange.giantcowfilms.com/

OMG I'M A CERTIFIABLE IDIOT! Thank you SO much!! I knew it had to be something simple!!!

You have to disable the Snap option. Right now it must be set to Increment, which means that the object will snap to the 3D view grid.

This is rather a comment.

what do you mean? Actually this is the solution he was looking for...

@Lukasz I added a manual link. Would you care to explain why this doesn't answer the question and what would be needed to answer the question?

@Leander, moonbots: this is a one-liner and I'm officialy told to avoid them every time I write them which is a rarity. Second It's a one-liner with a link, which is not welcomed here as far as I know.

Only a single user can be notified with @ - comments. I have read the help center and failed to find anything about "one-liners", only the statement Brevity is acceptable, but fuller explanations are better. . Even if the link goes down, the information is still there and OP can look up "Snap" by theirself. I think this does not have the negative aspects of a link-only answer. Either way, I would be happy if you added some info with an edit.

Lukasz-40sth, I first answered him with a simple comment, that's why I didn't feel the need to make a complete answer   ;)   but you were right, I've completed


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Rain - How can I get all hits to register in the image sequence?
I am trying to make a rain simulation with particles and Dynamic Paint - create wet maps and splashes on impact etc.
Everything is working except for one basic thing. The wet map is only picking up about half or less of the impacts so only some drops are getting hits on the image sequence. The rest seem to be ignored.
I have tried setting the substeps to max and this doesn't do anything.
Played with scale influence and radius as well. Even with scale influence on max it still doesn't register all the hits.
Tried upping the subdivisions of the rain instance geo ( icosphere ). No effect.
Thanks in advance !

I'm leaving this message to the time-travellers ... frustrated as me as well.
versio 01
The issue here is moving particle, that appears on one frame above ground and at next frame bellow ground. You need to increase Subframes of particle emitter object (left image) to increase chance the particle to be noticed by Dynamic Paint's Canvas object. I assume you increased Sub-Steps of Canvas (right image).

I used Weight in this example, but it is the same for Image Sequence output.
Even with high Subframes it can be hard to match all small particles at contact location per frame. For that people are using rain drop as a stick (basically 3 sided Cone), that increase drastically chance for DP. Reason for such drop shape is visual similarity with Motion Blur effect (so in animation at normal speed it is not noticeable).

Note: Subdivision of particle object doesn't make difference since Brush object is using its Volume.
versio 02
Anyway ... at my example with just particles (as Halo) I set ground Plane as Collider with Damp 0 so particles looks like Die on Hit or Killed, but like now I can control affecting Canvas by set particles Life-Time ...

Here also noticeable bug ... at Weight Paint mode particles doesn't respect collider object in viewport, but they are taken into account, don't worry.
Sure ... this works only for flat emitter and ground to all particles have the same time to reach distance from emitter to ground at the same frame amount. Sounds limited but usual case is flat road or street, so not a big deal.


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Wierd faces after I moved one vertex of quads
I am new to blender. I searched the forums for an answer to my question. I couldnt find any.

I loop cut a cube (vertical center)
I Pushed the loopcut on the Y Axis so the whole shape became like >>.
I pushed down the upper vertice of the head on Z axis.

This means I should get a VALLEY shape.
Problem : The side left tf the screen divides into 1 raised half and one proper half. This means i get a ^ shape bend instead of a / shape bend which joins in at the vertice. Please tell me how it can be resolved.
[

Ok man. I am new here so I didnt know. I will add in a few mins

See is it clear? Where is the Q? in blender edit mode?

Result comes from fact that by draging only one vertex of a quad face makes face non-planar, in viewport hardly seen as two triangles (there is not any other mathematical way to result). In real life if you take plate of glass and you would take one corner lower you would have to split plate by diagonal cut between any two corners.
In your case is one face triangulated in shorter (red) direction and second in longer (green).

Yet not sure how final surface should looks like for you, but you can create like negative shape from two triangles and "cut" it out by Boolean modifier > Difference from your base mesh.
Create a new object with two triangle faces. Like that you keep faces planar.

For Boolean modifier you will need a non-manifold mesh. So extrude it by Solidify modifier to create one close mesh. It is non destructive way. So you can go to edit mode and adjust the "cut" shape anytime.
Now use Boolean modifier for your base object to Difference it.
Also I changed the viewport display mode for this object to "Wire" so you can see how Boolean modifer perform on base mesh.

Note: Blender has also an operator, you can search Make Planar Faces, that can recalculate them into flat faces, but in cost of distortions of all selected vertices.

Ok. So I need to increase vertices? But that wiil increase my Vertice count.

What is negative shape?

You dont need increase vertices, it depence what final shape should looks like. I edited A. If it is not what you are looking for add some mockup - image from internet that looks like you want to end-up-with or your hand scatch drawing (shaded?) from which we can see how result should looks like.

Ok man I will try and come back to you. You are a real blender person. Others avoid hard questions. How can I save this answer to desktop?


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Camera Clipped View
I cannot figure out why the camera displays and renders a portion of the image, but not entirely.

I am attaching an image image of what the camera is actually displaying, and will try to figure out how to attach a 2nd image of the scene I am trying to accomplish

Thanks for your help

Does this answer your question? Render result is completely blank See situation number 11.

Try to turn up the clipping distance on your camera. You do this by selecting your camera, then goinh to it's menu over on the very right and turning up the Clip end.


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Baking normal map
Trying to bake maps but all i got its a mix of it. Why not separated? Who knows?

Thats the result i must have

Looks like the only problem here is transparency between the UV islands..which is the result of alpha channel present in the image. It's possible to preview it without the channel by toggling option in editor or eliminating alpha channel as It doesn't appear to be required by normal map.

To bake from hi-poly to lo-poly without a cage, you need to increase the Ray Distance. 0.5 or 1 should be fine.

It do not works. Not 1 not .0.5.

Then you might want to upload your .blend to http://blend-exchange.giantcowfilms.com/ and pasting the given URL into your question. Anyway, I'm still pretty sure that the Ray Distance is the problem. And maybe you want to give a more clearer description about what you mean by "separate".

I added the image which xplains 'separation'.

I wanted to upload. But it seems that my project is too big for that(-=


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Extrude curve given by mathematical equation
How can I extrude curve given by mathematical equation?
I know how it works for a Bezier Curve.

I tried to use Solidify modifier but it doesn't work

Okay, the problem seems to be that you need to turn off "u-wrap" and "v-wrap," in the function menu.
I also turned off show wireframe.

I tried using the solidify modifier on the xyz surface mesh you made, and it seems to work.
Is that not what you mean?

I edited my question, this is transparent in my case


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Only rendering a frame at a time?
I'm rendering pngs for an animation, and all was going fine, but 3/4 of the way through it stopped, and now it needs me to click "animation" to render each png, rather than just going to the next frame on it's own. My frame step and end frame are correct, and all was going well until frame 120/150

That's one of the situations where a blend file would be really helpful

all you have to do is change where it says start: 1 at the bottom where it says start to whatever frame you got to. So in your case it stopped at 120 so change start to 120 and end to 150 (or whatever frame is the last one in your render.)


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Render zoomed further than viewport
So I'm trying to render a scene, and everything looks fine in the viewport. But when I go to render it, it seems to have zoomed in way further than it's supposed to. I think it's zooming in on the backpack, but I have no idea why it would do that. There's nothing inside the camera, and there's nothing set to render that's not visible in the viewport. The first image is what it should look like, and the second image is what I get when I render it.

Can you edit your scene to only include the most necessary parts to produce the error and upload it to https://blend-exchange.giantcowfilms.com/. This way other will be able to help your more easily.

not sure what you meant about editing it, but here's the file (i think?)

It is due to the particle system set on the ground (coniferous)

Thank you! I'm not sure why that broke it since it wasn't actually in use, but I'm just glad it's working now.


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How can I put different textures/materials on different parts of the same mesh?
Title pretty much says it all. I have just started using blender 2.7, been on it for about a month, and have spent hours watching tutorials and reading and playing around with it.
I have built a model of a house, not for anything specific just wanted to do a whole model from start to finish as a learning project. I am happy with the model but I just can't get the textures to work. I am using cycles render but have also tried blender render. I textured the roof: marked seams>unwrapped>new material> nodes etc, and it looked really good, I was happy with it, so I marked seams for the door frame, unwrapped and set the texture and nodes etc but the wood texture applied itself to the roof as well as the door and made the rest of the model go a brown colour with out displaying the texture. I played around with the roof and got the right texture to display again, but it displayed on the door as well.
I really don't know what I am doing wrong, even when I follow a tutorial it doesn't work for me. I even tried a simple sword model, thinking the house might just be too much for a beginner, but the texture for the handle would assign itself to the whole model, none of my textures will stay seperate like I want them to.
This is really frustrating me as I am eager to learn and this would be an amazing skill to learn alongside my computer science degree, but it just won't work. Hopefully I am just missing something really simple and obvious, but a knowledgeable helping hand would be great.
Many thanks.
Edit: the post marked as the same as this one hasn't helped, I have worked through that thread a few times and it hasn't solved my issue. The uv maps won't hold seperate textures for me, blender applies the latest texture to every material and uv map on my project.

I have seen that post and worked through it quite a few times but it hasn't helped. I have tried using different uv maps for each part of my model but the textures I am applying are showing on every part of the model that I have worked on. I can't have a roof texture on the roof and a wood texture on the door and brick texture etc etc because every time I do the next section of my model it replaces all the previous textures I have done, eg: roof shows the door texture, then the roof and door show the brick texture etc.

Do you click Assign button each time you select adjacent parts of the mesh and create new material ?

I have tried clicking assign and new material, I've tried not clicking assign as well.

Every uv map I use has a different node setup, each one has its own texture node with a different image opened but whenever I do a different section of my model it over rides the textures I have already done.

Upload your file to http://blend-exchange.giantcowfilms.com/ so we can take a look.

OK thank you, I hadn't heard of that site. Will be able to upload it sometime this evening. Thank you.

I think you may be confusing different things or using wrong terminology. Uvmaps don't use nodes, and there is no way one texture could be bleeding into a different material slot. There are *Textures, Materials and UV Maps and Material Slots, they are all distinct stuff.

Im pretty sure my terminology is off lol, i am still really new to blender. What I meant was i make a new unwrap for each part of the model I want to texture, I then set up my nodes in cycles render, attach a texture node, point it to the new uv unwrap for that section and add any shaders that I want on it. It works absolutely fine on the first go, but when I do the next section of my model it all seems to go ok but when I attach the texture node it overwrites the texture I did previously for a completely different part of my model.

I have uploaded my .blend file to blend-exchange:

As far as I can see the question still is a duplicate. All the mesh uses one material. The reason for that is when material is created it's automatically assigned to all the faces. You should create new one, assign some faces to that and only then will you have those faces go away of the first material. To check where is material assigned click Select just next to Assign.

I have managed to do it. I think it was the way I was doing the seams which was messing it up. Thank you to everybody who took the time to answer and try and help, I really appreciate it. Thank you.

authors: Михаил Лебедев