Why does Cycles sampling give diminishing returns? This may seem like a obvious/basic question, but I am still curious, and I don't know the answer.

There will obviously be a big difference between an image rendered with a single sample and one rendered with 500 samples, but there will be a smaller difference between an image rendered with 1000 samples and 1500 samples.

What is the technical reason for this?

From what I understand of how cycles works, it fires one ray per pixel from the camera, which bounces and translates through objects at random angles.

It would make sense that samples would bounce in directions that have already been sampled, but I would think it would be possible to skip sampling "duplicate samples" by skipping bounces that are at a similar angle to previous bounces?

Cycles and all other path tracing render engines use Monte Carlo integration. The probabilistic error after N samples of Monte Carlo integration is:

This means that to halve the noise you have to take roughly 4x more samples.

Actually, we can do a bit better. You mention skipping samples in directions that have already been sampled, and we do this to an extent. Cycles uses Quasi-Monte Carlo integration, which means it uses a sequence of random numbers that is distributed well over all directions to avoid such duplicate samples.

Quasi-Monte Carlo has better convergence than basic Monte Carlo sampling, but it's difficult to quantify and depends on the scene and settings. The integral for global illumination is high dimensional which makes things quite complicated.

To halve noise you need somewhere between 2x and 4x more samples in practice.


How can I create a model like this? (see image) How can I create the models like in the image quickly?

When I rigged a figure I made and tried to animate it, the arms and hands were not bending correctly. I used separate objects for the head, hands, abdomen and so on, and then combined them using Ctrl + J.

There may be multiple ways of achieving this but I will be using metaballs for now as they offer a quick solution. Add metaballs on the fly, adjust, when you get an acceptable mesh, convert it to mesh ( alt + c), sculpt, add armature and pose it to achieve the final look.


I want to smooth only the outer faces of a circle I am currently working on a medal where I want a smooth the extreme outer part of it but without touching the rest especially the upper face.  However even when I add one subdivision modifier, I get the result I want but the upper face grove lines emitting from the central circle are ruined.  A you can see in the photos.

I  have marked the edges as sharp (Edit mode/mesh/shading/sharp) but without a result.

OK, for 3d Print this should work fine:

Add 2 edge loops along the sides.
Press CRTL num plus to extend your selection, so it covers the entire rim
W -> subdivide
Choose these options (lower left at your VP imediately after hitting subdivide)

You might need to tweak the rim, bc. it may become concave. Easiest would probably to delete the new edge loops around the "coin" again.


Help with an alpha brush - camera setup So I was trying to make my own alpha brushes.
but I have a problem with the opacity at the edges of the brush...
Not being so familiar with blender nodes i'm really not sure how to adjust the settings to achieve a smooth transition outwards.
I think likely its either my camera settings or the adjustments to the image...
I'm still trying to adjust the settings and keep tweaking it... but hopefully someone has some ideas what might be causing the problem.
rendered image also has a slight gradient visible below ... ill try playing with the distance... maybe that will help.?

you tube vid of problem

your sample bias setting is screwing you over here. I tried your first file, and just loading as a texture, and using it without any editing, on Area plane, anchored mode, and custom falloff set to all max, it worked fine. I would however suggest you didn't use the fade on the edges, seeing how this alpha is a full object with hard edges, and not truly just a texture, but a belt buckle...?
in any case, blender accepts black-backed alphas by default, because they're easier to produce and provide much more detail in the most often used direction. Generally, grey-backed alphas (the background grey at 50% brightness) is used in alphas with both positive and negative deformation.


How do I get a better understanding of the coordinate system in blender? With link to this question, one of the main problems that have not promoted the understanding of the node system with Cycles is blender's coordinate system.

These coordinate system values are said to have been represented as RGB values(e.g. generated, object, normal etc.), analyzing the output with the viewer node and mapping node, I'm not being able to get how this actually works:

I can't really interpret how it really works. Example in the image above, the location and scale are basically almost the same thing viewable.
It's not even a constant RGB(don't know how to put it), there's a gradient of the RGB values, so I don't think it could be an offset representation from the bounding box origin. So, summing it all up, how does this work in blender?

Generated coordinates

Here is a simple base setting, converting the 'generated' output to color.

Generated gives a vector composed of X, Y and Z space coordinates. But these space coordinates are limited from 0 to 1 along the bounding box of the object.

X, Y, Z, put into a color, respectively correspond to R, G, B values of the color.
So, black is at the origin (0, 0, 0) and with is at the opposite (1, 1, 1).

To check that the values correspond to the bounding box and are not above 1, we can try this experiment :

Add an independent vertex inside the mesh at its lower corner (the black one), and change the setting of the nodes like this :

On the image above :

Top left, the cube vertices are shifted, but the bounding box is larger thanks to the independent vertex we added before
Bottom, a holdout is applied if any coordinate is bigger than 1
To right : the result. The cube is nearly white because X, Y and Z are closed to 1. And notice that no holdout is applied (so nothing is bigger than 1).

Color

Try these two setups :

Same color (apparently), but different input values.

But we can check that the resulting color has a G value over 1, thanks to the hold out again :

So here we now know :

Concerning the generated X, Y, Z values : between 0 and 1 along the bounding box
Concerning the color : eventually above 1, but "no direct impact" on the rendering if above 1 (let's say that the diffuse shader does not take care if > 1, so the shader limits the value to 1)

Mapping node

We come back to this kind of setting :

If we shift the X value over 1 (3 below), finally the shader will show it as if 1.

If we scale up the X value (30 below), rapidly as X grows the value will be over 1. If 30, the value is > 1 when X is 3.3% of 1 = 0.033.

That's why the final result is the same, except for the slice where X is between 0 and 0.033.


Alpha channels in cycles canceling out each other I have two images with alpha channels that overlay each other. In Eeevee it works fine but in cycles, the front image's alpha channel blocks out the image behind it. Is this something that can be fixed by some adjustment in the cycles settings?
Thanks,
Rusty

One possible reason could be that in the Cycles render settings the "Max Bounces" for "Transparency" are set too low. Since Eevee is not a raytracing engine it doesn't need those settings. The default settings however should be high enough. With two images Transparency bounces must be set to 0 to block out the underlying image.


Materials in the game engine have no shadows I am trying to make a game in blender, but any material that I add to anything in the game has no shadows

Use dynamic shadows. Check the shdow propery of your lamp object.

Or bake your shadows in blender render or cycles, what can lead to better performance, however they will be static.


My water simulation (preview) outline is not clear? I am a newbie to Blender, I have followed a tutorial (Blender Guru) on how to make a water simulation. The water has a dark outline instead of being completely clear!

I have set this test render on 20 samples. What have i done wrong? The background is the lighting so maybe the background needs to be brighter/darker?

Is it supposed to be like this? Any help is appreciated!

This was made in cycles render engine, the final render will be on 450 samples..

set my enviernmont texture and used the background as the texture. how is this?

It looks like you just needed more lighting. The water was reflecting your black background, so thats what you see.

I just added an HDRI and it seems to look a little better.


How to render an Equirectangular Panoramic image with Eevee I want to use Eevee to render 360 panoramic images. I do not want to use cycles because of the render time for my project. I tried searching google and this site but the last time this was asked was about 2 years ago: Is it possible to render 180º equirectangular with eevee engine?
My only thought is to create multiple cameras, render each camera and then stitch together in another program. Is there an easier and faster way?

There is this VRRenderer script by EternalTrail that works okay for rendering a stationary camera. However it does not animate and the camera cannot be parented to another empty or object. (Correction - it can render an animated camera or imported camera, please read the update below)
Here's a video explaining how it works.
https://www.youtube.com/watch?v=ND8T5_VCcN0
I have tried installing it as a addon as described in the video but it didn't work for me, what worked is opening the python script directly in the scripting tab in Blender and then running the script. Following that you should be able to see the eeVR tab on the side of the viewport. You have to save the blend file for it to run and also it writes the renders in PNG and into the same folder of the of the blend file. Seams will appear if you turn on AO and bloom in Eevee. Turning on overscan will apparently fix the problem but I have yet to try it.
Guess I'll have to wait for the Blender developers to come out with a dedicated Panoramic renderer for EEVEE. Cycles is good but the render times just take way too long when time is limited.
Update after some experiments.
I have trying to use an imported alembic cache export from Maya and although I can see the camera animated, the VRrender script does not want to render from the camera. As explained earlier, this is a limitation in the script. I tried deleting all the cameras and used a single camera and the script automatically renders to that camera. I tried manually keyframe animating it and the renders correspond to the keyframed animation. Eventually I figured out from other forum posts that I can just duplicate the alembic exported camera, delete its alembic constraint, then apply a transform constraint to follow the alembic constraint camera. Following that I select the duplicated camera, then go to Object => Animation => Bake Action to bake the keyframes into every frame. In the Bake Action options, I turned on only Visual Keying and Clear Parents. My Camera animation had over 2700 frames so it took a while for the keys to be baked. This is the workaround I'll use until the official Panoramic EeVee render is available.


How to load a video in a MovieClip node How to create a "CompositorNodeMovieClip" node and load a video using the python api in the node editor.

My progress so far...

bpy.context.scene.use_nodes = True
nodes = bpy.data.scenes['Scene'].node_tree.nodes
links = bpy.data.scenes['Scene'].node_tree.links # create the movieclip node
movieClipNode = nodes.new("CompositorNodeMovieClip") # get the video clip
videoClip = bpy.data.movieclips.get( videoPath );

but videoClip is returned as null..

you are using incorrect key , the key is the name of the movie clip

#load new movie clip
bpy.data.movieclips.load(clip_path)
#get the new movie clip
movie_clip = bpy.data.movieclips.get(clip_name)
#assign movie clip to the node
bpy.context.scene.node_tree.nodes['Movie Clip'].clip = movie_clip


Removing cusp/crease when using array, mirror and subsurface modifier Below image shows the shape I'm trying to make seamless, I have mirrored it once along the highlighted edge and ensured the stack is in order to avoid a crease.

However in the below image, after I've made an array of the shape I'm getting a crease on the array seams. Is there a way to remove/blend this crease as well as in the previous mirror?

Stack order:
Mirror
Array (With Merge option ON)
Subsurf


How do you make a cube with another cube inside it? I am making something similar to a slime in blender, with softbody.
I don't really know how to put a cube in it, with a darker color.

Try putting one cube inside the other, and use a Material like this on your outer cube:

Transparency can be a bit of a pain in eevee sometimes, so I opted for this form of shader graph to give you more control. You can change both the BaseColor as well as the Glossy tint separately (to get that slimy look), as well as change the IOR of the Fresnel if you need the slime to seem thicker/thinner. Also because of the way EEVEE handles transparency, the inner cube cannot be transparent as well (unless you are using a single material - the graph for which is substantially more complicated). Because of this, it doesn't matter quite as much what material you give it (I used a copy of the same one for time savings sake - I just disconnected the Transparent and associated Mix Shader).
Lastly, I threw in a Noise Texture as a Displacement to make the outside more "slimy" and bumpy looking as well. Also, pay attention to the Blend Mode highlighted on the right (switching away from opaque is necessary for transparency in EEVEE)


How to render mist path as png sequence in Eevee? Is there any way to do this? Stil mist path image is cool but I need 2000 frames of it to control the depth of field of my animation dynamicly.

I'd like to add that you don't have to render your animation twice, you can output as many passes or composites as you like at the same time using a File Output node:

SHIFT A -> Output -> File Output


Particle system hair lines are facing downwards. How to make them facing upwards? I was creating a doughnut following a famous Blender tutorial on YouTube. I duplicated the upper part of a Torus and made them into a separate object. At this point, when I added a particle system (hair), the hair lines were facing up.

Then, I deformed the object using the sculpting mode. At this point, if I add a particle system, the hair lines look like below; they are facing downwards. I have searched Google and found answers and posts about moving the origin, but it did not work. Is moving the origin the answer? I am using Blender 2.81.

The project file can be downloaded from this URL: https://filebin.net/pyj0vqo1787i4y1r/test.blend?t=uco3o5we

It seems like a Normal problem. Particles have a reference direction based on the poly surface. Try to flip your normals as you rather a hairy doughnut than a bearded one. This is a good article: https://www.katsbits.com/codex/flip-normals/


Values of the normal of a selected face I need to be able to find the normal of a selected face (given that we are in edit mode), or be able to compare the position of the face to the origin of the object. I have no idea how to start either of these things because I'm new to blender python scripting. With any advice you already have my thanks.

You'll need to :

import bpy

Then get the object you want :

obj = bpy.context.active_object #The active object
obj = bpy.data.objects['Cube'] #The object by its name

Then for the object information :

obj.location #Object position rotation, scale
obj.rotation
obj.scale

Object faces are in data.polygons :

p = obj.data.polygons[0]
p.select #Indicates if the face is selected
p.normal #The face normal
p.vertices #The vertices indexes

The vertices and their positions :

vIndex = p.vertices[0] #Index of the vertex from the face p
v=obj.data.vertices[vIndex] #The corresponding vertex object
v.co #Its coordinates

It can be a good way to learn how to navigate through the objects hierarchy using the Python console and CtrlSpace for auto completion and discover the object properties (in complement to the documentation) :


Can we add or remove bones to a Metarig with Rigify add-on? I'm adjusting a metarig (a skeleton) for a bipedal character mesh with the Rigify add-on. But I want to remove the metarig's bones for the face and add some bones for the feet (my character has long floppy flippers).

My question is: With Rigify, can we add or remove bones to the original skeleton without breaking the rig's widgets before or after we push the button "Generate rig" ?

Short answer is yes. The process is a bit more involved if you want to use all the features.

To delete the face, highlight/delete all the face bones, including a bone inside the head called "face". I suggest you hide the head bone,  or "spine 06" in 2.79, box-select, delete and unhide.

For the toes, add them as children of the "Toe" bones. For the extra functionality, you will want to:

Pose Mode > select the root of each toe bone you just created
In the Bone Properties Panel and find Rigify Type (bottom panel) you can choose limbs.simple_tentacle, limbs.super_finger or basic.copy_chain.
In that same panel, choose the layer where you want the Tweak Bones to be. You can look them up in Object Mode under the Data Panel > Rigify Layer Names


Cycles : shadows on smooth shaded mesh, strange behavior I wonder if this is a bug, or if I missed something...
When a light hits tangentially convex surfaces with "smooth shading", the shadow on this surface seems to "partially ignore" the smoothness of the surface. Here is an example with a simple cylinder :

On the left, a cylinder with "flat shading". Everything's ok.
On the right, the same with "smooth". We can see an edge, bad shadowed.

With or without the "Edge split" modifier, no matters, the edge is still there. The shader is a simple white diffuse shader with no texture nor displace.

I have to add a subsurf modifier with at least 2 levels, which will insanely increase the vertex count... And I can't do that for my project.

I hope someone already saw it, and have a little tip to share. Or if someone already know it's a bug, or a limit of the current Cycles renderer ?

I believe what you're looking at is called the "Terminator Problem" which is a ray tracing issue. I think most rendering engines actually suffer from this problem.

I think the solution is to add more geometry or play around with your lighting setup.

You can read more about it here.
https://developer.blender.org/T37814


Wierd line that disappears in edit mode There's a line in my project that I don't want. I dont know how it got there, and I don't know how to remove it. It just sits there. If I right-click on it, it says that it belongs to an object on the opposite side of where this line is!

If I enter edit mode, (which is what I did when I tried to remove it,) it disappears!

Does anybody know what this might be, or even better, how to fix it?

It looks like some stray edges.  Go into edit mode and press ctrl+shift+alt+m to select the non manifold geometry and then press x delete it. This can't be done in face select mode.


Blender crashes entire PC on Cycles rendering - need help diagnosing the problem I have a MSI i9 PC (32 GB of ram) and a RTX 2080. The computer crashes on any Cycles render but for our purposes here, I'm using the Blend file attached to this ticket.
Here's what I've done to diagnose so far:

Used 2.92 and 2.93 (beta)
GPU and or CPU rendering.
Optix or Cuda
Memtest tests pass
CPU and GPU stress tests pass (running for 30+ min)

The crash happens every time within the first minute of the render. One time Blender crashed (didn't freeze the computer). Here's the crash file.
Here's what the screen looks like EVERY time it crashes.

Any ideas on how to diagnose this issue?

This is most definitely a hardware issue; but don't despair, the fact that it isn't with Blender doesn't mean it can't be fixed. I rendered it on 3.0a on my own machine (desktop, Linux Mint, FX-8300 processor with a GTX 1660 GPU) and it rendered fine.

That looks like a laptop screen, and if I'm right, the first thing I would suggest doing is checking its operating temperature. If you've got an RTX 2080 in there it can't be more than a few years old; but you would be amazed at what I've seen a little stray cat hair do. Cooling mats exist for this very reason, though to be fair, it's also why I stay the heck away from rendering on a laptop when I'm anything short of desperate. But, you use what you've got.
I'm also noticing that your i9-9900K, which is rated for around 3.60 GHz, is reportedly jumping to 4.55 GHz, which causes a massive heat output increase. (Massive.) Do you have your machine overclocked in its UEFI settings? Because for 3D modeling, overclocking is definitely not your friend, and you should consider switching it all off and waiting on it. There's a very good reason that those aren't the factory settings. This would also explain the wait time of a full minute before your entire machine goes down.
If neither of these is working, then the traditional debugging method is to simplify until it stops happening, and then isolate the probable cause. For "any cycles render", does that mean even for the default cube with no material added? At any resolution? Have you checked the Blender error log, traditionally (on Windows) at C:\Users[your username]\AppData\Local\Temp\ ? That may contain useful information for you. (They always end in ".crash.txt", though I haven't rendered on that OS in a long time.)
I would suggest turning off any overclocking settings if you've switched them on, and grabbing a cheap cooling mat. If it doesn't do the job, most stores will accept them for returns. Nine out of ten it's your temperature getting out of control. Grabbing some electronics-safe compressed air, and maybe some cotton swabs and rubbing alcohol, and cleaning out the vents won't hurt you either. At minimum you should keep it elevated enough for proper heat exchange. (In a pinch after a hurricane, I once managed that with a cooking grill... long story.)
Hopefully that will help you get to the bottom of this. Good luck! And props on the H✭R poster, you make me feel less old.


PC Freezes while rendering If I try to render a image in Cycles, the PC renders like 3min then the Screen freezes. I can´t move the mouse or do anything. I tried to render with Graphic Card and the CPU togther, only cpu and only gpu. The PC freezes every time.

My specs:

Graphic Card: AMD Radeon 580
CPU: AMD Ryzen 5 2600
RAM: 8GB
Mainboard: Asus Prime B450

Thanks for every answer!

you must be using to high resolution or to many samples or to high poly count

https://www.youtube.com/watch?v=8gSyEpt4-60

tutorial for lowering cycles render time/workload on the computer


Cloth sim sag between pins I'm trying to get something that looks like a cloth object pinned to the wall at the corners and centre using cloth sim.  I'm having a few issues (not getting enough wrinkles and creases, etc), but currently the biggest problem I have is that the top edge of the object remains almost perfectly straight, whereas a real cloth object pinned to a real wall would sag a bit.  I think getting the correct sagging behaviour would improve the other issues I'm having with lack of creases.

I'm starting with a plane object pinned in 3 places, with a simple cube behind it to serve as a wall to collide against.

My cloth sim is configured as such:

When I run it, the results aren't too bad, but as you can see the top edge of the banner is more or less perfectly straight, as if the fabric is being stretched between the pins, where in real life the cloth would sag a little between the pins if it wasn't being pulled taut.

I think if I could get the actual pin position to be slightly closer together than the vertex group pins then that may help produce better results.  I've tried messing with weights and having different starting angles for the flag when I run the sim, but the top edge always remains straight.
What can I do to improve the results from my sim?
EDIT: I've tried using the "rubber" preset instead of the "cotton" one, and whilst that does product sags, it also doesn't produce much in the way of wrinkles in the material.

Default settings, just changed stiffness has indicated below:


Color picker default behavior? Just a theoretical question here.
Why is the color wheel selector in blender white in the center? Is there any reason not to use the neutral colors that usually are in the center of the color wheel?

You can change the color selector type in the user preferences.
To open user preferences, press CtrlAltU then under the System tab change the Color Picker Type. I think you may be looking for the Circle (HSL) type.


Is there a way to visualize border edges of meshes? When editing a mesh, it sometimes happens that two faces are seemingly connected by an edge, but these are actually two edges on top of each other. Often enough I only notice this way later. For example when moving one of the faces, revealing the hole in the mesh.

In Maya there was an option to highlight border edges. Does Blender has something similar?

Or this there another workflow in Blender to detect gaps?

Did you mean check non-manifold?

Type select non manifold in search-bar (F3 or Space) in verts select mode(edit mode) when selecting nothing.

It will help you to select something not manifold including separated holes


Blender renders plane in distorted way when enabling displacement only vs. bump displacement I'm trying to use a plane with an image texture to render a topographic map of the US. When I add a subdivision modifier and use a bump only surface displacement, I have a fine looking map:

When I try to use displacement only, however, I get this much less fun looking thing:

Is there a reason for this, and if so, what can I do to avoid it?

p.s. I'm very new to blender, so please forgive anything egregious in the wording!

edit: here's my set of settings for reference:

You have the Strength property on the Displace modifier turned up too high. Turn it down to 0.1 (or lower).


Texturing problem distorted and messed up I'm having a little trouble with texturing this blasted coffee cup- When I place the texture onto it it comes out warbled and distorted.

It looks like you have a lot of vertices along your vertical edges, you should try to delete them with a X > Dissolve vertices and see what happens.


How to create parallel edge between vertex and edge? I'm pretty new to blender, how would I create an edge between the marked vertex and the edge.
The edge I want to create would follow the same direction as the edge above it.

the Toolpanel (t-key) have no Join tool maybe you lock for.
But operator exist in the edge or vertex menü to solv your problem.
Mouse rightclick brings  a compact menü with operators
but depense on the select modes you choose (vertex,edge,or face) .
and left click or rightclick 2.8 Mode you use and  choose .

It could be that joining from a vertex to edge needs extra steps or actions.

So.
Select the edge thats needs the conection  with
 activ 'edge select Mode '.
and then
rightclick with the mouse and  look and  click on  the  edge Menü operator

'subdivide edge'.

This subdivide the  edge  and creats one new vertex in the middle of your selected edge .

Now use the vertex select Mode.
Select the  new created vertex on your edge  hold shift key and select the second vertex .
rightclick with mouse and find i
n the vertex  menu operator    called 'Join " .
That it.
a new edge conection between your vertex and edge(new vertex) is created that flows like you want.
Wfg


Why does my mesh rotate face down when i delete my bone? Ok so, I got this bone that I wanted to get rid of so I can start over with fresh new ones.
The bones were once weighted with my legs mesh but then I deleted them.

So when ever I delete the bones my entire leg mesh just turns face down and move a little out of place.

Why is it doing this? it's kind of annoying.

Here's what I mean.

That's how it looks totally normal.

This is how it looks all wonky and crap..

I'd appreciate it if some gave me a hand. Idk if this is like some sort of bug, or what?

Are you sure the bone you are deleting is not the parent to any other bone, because if that is the case their parent would become NULL and the tranformation they were inheriting will become garbage (or maybe just 0 in Blender).
So make sure you undo parenting prior to deletion.


How do I make the Particles and Curve Guide Work? I have a sphere and added particles to it. The curve was selected. In the physics tab i selected the force type as curve guide. Why are the particles not following the path? The particles still dropping down. Whats going wrong? Any suggestion or help. Thanks

Simple Fix

With the Curve selected ... Click on Path Animation which is depicted below with the Yellow Arrow.  Fix with a Click.  This might seem unexpected to you.
Use the curve guide settings below.  There is a goal to help the OP achieve his/her desired visual. The OP can still specify the goal in the original question.
Change the Particles to a longer lifetime. Easier Visibility.  Later Change to your Artistic needs.

Path Animation Clicked. Curve Guide Works. Spiral not so obvious. Curve Guide Settings not to OP Artistic taste perhaps.  Image above.

Curve Guide to fulfill Artistic taste of OP. Spiral Very Obvious. See the settings in the Curve Guide Panel.   2 Images Above.

Change the lifetime of particles in the particle panel of the sphere. Image Above.

Notice the Circles magically appear on the ends of the curve. Image Above.

Particles in Ascencion.


How to make phosphorescent material I was wondering if it's possible to make a phosphorescent material that stores the light-energy. I don't mean like fluorescent just by putting a emmision shader.

I mean if light shines on it and then you mute the light, the material stores the light for a period of time until it fades out into darkness. You get this material sometimes on the pointer of analog wristwatches or like on fluorescent jackets.

Hope my explanation is clear

I provided a video for better clarification, also used Eevee because the render is fast, but you can use cycles too.

What you want is to simply animate a emission property and a light brightness, in the case of cycles, you could use only the emission shader.

You will also need another shader when the light fades off, so you mix the emission with the other shader, for a nice effect, I applied the same texture to the emitter. To the sphere to not cast shadow, I simply set the shadows to none in the materials tab.


How can i make something Invisible if the Light is on? So i make a "Lights Out" animation and there is a light that is flickering and I want to make a Person Invisible when the Light is On and Visible when the light is of. How can I do that ?

First click the camera icon in the outliner to be active or inactive then you insert a keyframe .You insert a keyframe by pressing the letter I while the mouse is over the camera icon.  Or context click to see the menu appear with a choice insert keyframe.

I suggest inserting at least 3 keyframes and traveling through the frames to see how the setting is maintained until the next keyframe.  Look at the camera icon and see if it become bright and then less bright or muted while moving the frame position.

The render visibility camera icon and the 3D View visibility eye icon near the arrow. Yellow indicates a keyframe. Image above.

Please know that for options and convenience the camera render icon does [not] affect the 3D View.  You must press render to see the difference.  You can animate 3D View visibility of the [Person] with the 3D View eye icon in the outliner near the camera icon... and that is your choice. It may be useful to know where the [Person] is, even if [ Person] is not rendered on some frame. Blender can suit your needs. You may also keyframe the 3D View drawing of  the [Person] as wire or bounds. The hint of the [Person] may be valuable.

You might even consider changing layer visibility to avoid clutter.
If you have a simple still shot ... you can move objects off the viewable area. This idea is for simple circumstances only.


How do I produce a final rendered image using Cycles in Blender 2.8 in the Image Editor, as before? There doesn't seem to be a button that when pressed would produce a render in the image editor, to the specifications made in the rendering options.

This is still possible. You can configure it in Render > Display Mode > Image Editor


Shadow catcher not working? I have made a car model and i'm ready to render , I decided to try to make a shadow catcher plane ( which has never worked )

Im using and HDRI image and set up the nodes correctly , yet it still doesn't work.

As said in the comments you cannot use HDRIs to cast shadows but the reflections are still showing up. You can't render the first layer without that transparent options else you won't be able to add that Shadow Plane correct? So here is my Solution:
For the first layer enable Environment Pass and then add it in the compositor like this:


Different shading on same objects These two objects have same settings (same material, same object settings, both are cut out + extruded pices of a sphere), but the smaller one has wery different shading. How to fix?

all the normals are OK

Select the loopcuts (one by one) and use the edge slide CTRL + E --> edge slide. and move them to the sides. Or you can move them by pressing G two times so it will slide along the edges.


Making a realistic infinite mirror tunnel You know when you're standing between two walls that both have mirrors on them and it makes it look like each mirror is an infinite tunnel going into oblivion?

Something like this:

(photo from Daniel Hong's website).

So, I'm trying to achieve the same effect in a claustrophobic elevator scene, using planes with a glossy material, and it looks like the reflections somehow stop or become very dark after a few bounces:

How could I make the light fade little by little after each bounce and not really ever become completely black?

To make more bounces:

Go to render panel and in Light paths section increase Bounces on Min, Max and Glossy

To get rid of Darkness:

Go to materials and change both mirrors color to pure white:


Where is User Preferences now in Blender 2.8? It's no longer in the File menu, it seems?


Optimize Blender's user interface for performance As a simply a Blender hobbyist, I can't justify the an upgrade  to improve the performance of my computer. I wondered, "What could I do that I'm not already doing that could make Blender run faster?" I realized that lowering quality settings in the UI could help lighten the load on my machine.

What GUI settings, preferences, or add-ons are there to help optimize Blender's performance?

I realize that changes like these could have only a trivial effect on overall performance, but I'm really wanting to squeeze every last drop of computational power out of my machine.

I'm looking for optimizations of any sort, including GPU performance, CPU performance, and memory efficiency.

Thanks for your time!

In The System tab of User Preferences goto Opensubdiv Compute and try using OpenMP or CPU.

Also on that same tab, scroll to the bottom and increase your Memory Cache limit. It should be set to 1024 by default. If you have 8gb of ram, then click that box and type *7 after the number 1024 (so 1024*7) which equals 7168, which means that blender will use 7 of the 8gb of RAM for memory. Be careful and play around with this value, try to stay in multiples of 1 so you use 1, 2, 3, 4 ect GB of RAM.

To better fine tune blender to your machine, read up on the settings available to you in the user manual.
https://docs.blender.org/manual/en/dev/preferences/index.html

I would suggest working in blender internal, as this side of blender is not so resource intensive. You may also want to work on low poly projects. This will also help you with modeling.
However, if you would like to speed up renders in cycles, take a look at this video: 18 Ways to Speed Up Blender Cycles Rendering - https://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=2&cad=rja&uact=8&ved=0ahUKEwiGiNO38abbAhVhITQIHcloBGAQFggxMAE&url=https%3A%2F%2Fwww.youtube.com%2Fwatch%3Fv%3D8gSyEpt4-60&usg=AOvVaw2jR9KDsJDWUto-lZ-N4csG

You could also optimize your windows start up by removing things that you don't need to start when your computer boots up. De-fragment, and uninstall any programs that you don't use anymore. Aside from that, I do not believe there is much you can do without upgrading your hardware.

You can also render files without blender open, to my understanding, from the command line. There are several tutorials on youtube about this. And even addons to use for this purpose.


Rigid body objects exploding I have a rigid body simulation where all the Suzanne heads are exploding outwards and going through a solid object and I can't really find out why. I am using blender version 2.8, any help would be appreciated.
I want the Suzanne heads to pour out of the box into the bowl. The box is animated.

these are the Suzanne head settings

I figured it out, the issue wasn't with the Suzanne heads but with the box they were in. It's collision was set to Convex_Hull making the box solid all the way through instead of being hollow. Therefor causing the Suzanne heads to fly outwards. Simply changing this setting to Mesh did the trick. Thanks to everyone who tried to help.


Determine if object is bezier circle curve? I'm trying to modify my local copy of dynamic spacebar to include a "Snap to Curve Intersection" option on the "Snap Cursor Menu" starting with circle-circle intersections and circle-path intersections for straight paths that will snap the cursor to the closest intersection to its existing location.  I've gotten as far as making a new menu option that only appears enabled when two curves are selected and broken out a separate curveIntersect function to encapsulate the whole thing but I'm having trouble finding a way to distinguish curve types.

So the questions here are:

Does anyone know how to determine curve types from within an addon, or are those only applied at the time of curve creation and all checks would have to be based on their vertices?

Is there already an addon that does this which might save time, or a function built into Blender to handle curve intersections that could be called to pick the from a list of vertices by distance from the existing cursor position?  (so far I haven't found one anywhere in the API)

Worried I might have to go at this completely from scratch as my existing repository of c# functions for 2D geometry doesn't include bezier intersections I might port over to python.

this will return the curve type

bpy.data.curves['curve'].splines[0].type

the output is in  [‘POLY’, ‘BEZIER’, ‘BSPLINE’, ‘CARDINAL’, ‘NURBS’]
for more info Spline


ReferenceError: BMesh data of type BMesh has been removed cause and fix I've made a lot of scripts that had this error: ReferenceError: BMesh data of type BMesh has been removed. While I've usually found workarounds I would like to know what causes this error and how to fix it for future scripts.

Edit:
This is my fence.

import bpy
import bmesh

class Create():
    mesh = bpy.context.active_object
    bm = bmesh.from_edit_mesh(mesh.data)

    def Verts(self,pose):
             self.bm.verts.ensure_lookup_table()
        self.bm.verts.new((1,1,1))
        bmesh.update_edit_mesh(self.mesh.data

class Modal(bpy.types.Operator):
    bl_idname = "object.modal"
    bl_label = "Modal Op"
    bl_description = "Other thingy"
    bl_options = {"REGISTER"}
    @classmethod
    def poll(cls, context):
        return True

    def invoke(self, context, event):
        bpy.ops.object.mode_set(mode='EDIT')
        context.window_manager.modal_handler_add(self)
        return {"RUNNING_MODAL"}

    def modal(self, context, event):
        c = Create()
        if event.type == "LEFTMOUSE" and event.value == "PRESS":
            c.Verts((0,0,1))
            print("Test")

        if event.type in {"RIGHTMOUSE", "ESC"}:

            return {"CANCELLED"}
        keys = ["WHEELUPMOUSE","WHEELDOWNMOUSE","MIDDLEMOUSE","LEFTMOUSE"]

        for i in keys:
            if event.type == i:
                return{"PASS_THROUGH"}

        return {"RUNNING_MODAL"}
def register():
    bpy.utils.register_class(Modal)

def unregister():
    bpy.utils.unregister_class(Modal)

if __name__ == "__main__":
    register()

Assigning class properties

The error you were seeing was in the way you were setting the bmesh in your Create class. The property bm will be the bmesh for the context edit mesh when the sctipt was run, rather than, what you want,  when the operator is invoked.

Suggest rather than instancing the class in modal loop, make one instance in invoke and use that.  Add a constructor to your Create class with an argument context to ensure it is for the context mesh.

Example where the bm is set as a class property of the operator.

import bpy
import bmesh

bmeshes = {}

class Modal(bpy.types.Operator):
    bl_idname = "object.modal"
    bl_label = "Modal Op"
    bl_description = "Other thingy"
    bl_options = {"REGISTER"}

    bm = None

    @classmethod
    def poll(cls, context):
        return True

    @classmethod
    def bmesh(cls, context):
        me = context.edit_object.data
        cls.bm = bmesh.from_edit_mesh(me)

    def invoke(self, context, event):
        bpy.ops.object.mode_set(mode='EDIT')
        self.bmesh(context)
        context.window_manager.modal_handler_add(self)
        return {"RUNNING_MODAL"}

    def add_vert(self, loc):
         return self.bm.verts.new(loc)

    def modal(self, context, event):
        # no longer in edit mode
        if context.mode != 'EDIT_MESH':
            self.bm.free()
            self.bm = None
            return {'CANCELLED'}

        me = context.edit_object.data
        if self.bm is None or not self.bm.is_valid:
            # in edit mode so try make a new bmesh
            self.bmesh(context)
        if event.type == "LEFTMOUSE" and event.value == "PRESS":
            v = self.add_vert((0, 0, 1))
            # update after all operations
            self.bm.verts.index_update()
            bmesh.update_edit_mesh(me)
            print("added", v)

        if event.type in {"RIGHTMOUSE", "ESC"}:
            return {"CANCELLED"}

        if event.type in ["WHEELUPMOUSE","WHEELDOWNMOUSE","MIDDLEMOUSE","LEFTMOUSE"]:
            return{"PASS_THROUGH"}

        return {"RUNNING_MODAL"}

def register():
    bpy.utils.register_class(Modal)

def unregister():
    bpy.utils.unregister_class(Modal)

if __name__ == "__main__":
    register()

For panel code to have an edit mode bmesh I often use a global dictionary

bm = bmeshes.setdefault(me.name, bmesh.from_edit_mesh(me))

which can be set / cleared using the panels' poll method.


How can I push down an action with only modifiers https://www.file-upload.net/download-12536795/push.blend.html
In this file (on the camera) I have an action with only modifiers (in this case noise) - but I can't push that track down in the NLA Editor, if I click the button nothing happens. When I try the same thing with python it says "action has no data". How can I do this then?

Already found the solution:
Bake the curve - because, at least in this case, the modifier replaces it, but the Editor won't grumble about no data being present


Solidify issue at sharp bifurcation location I am trying to solidify a stl file which has a sharp edge at the center. When I try to solidify, there seems to missing faces in the solidified region. Normals seem fine. Any thoughts on it?
Sorry if its a noobie question :)!

Best,
Rahul

You have two main issues.  The first is that you have a transition point which is joined by a single vertex.

That one vertex will cause you problems with several areas of Blender. Sculpting, Rendering and generative Modifiers to name a few.

There is no face at that center point and I imagine this is what's causing the Solidify Modifier to fail.

The other problem with this model is that the quads have all been converted to triangles and the loops are sort of spiraling around so un-triangulation is certain to fail because there are no loops with clearly defined axis.

Without quads that have well-defined loops, some important modeling tools will not work. So to start with we should try and avoid this as best as we can with the repairs to follow.

You can start by selecting all the vertices around the edges and use 'Make Face'f so there is a well defined face to start working with.  You can do this by using Alt+'Mouse-Select-Click' on one of the boundary edges.  In this case it will select both perimeter loops since they are attached but you can simply unselect the second loop to get started.  This will be easier to do in wireframe mode using the Circle-Select toolc and 'Menu-Select-Click'(this will un-select).

Now with the new face selected use 'Extrude'e to extend the edges out into some extra faces.  Repeat this for the other side, select both faces and use xthenf for 'Delete->Faces'.

Now you can also run 'Remove Doubles' from the 'Specials Menu'w to clear up some of the overlapping Vertices.

Once you've done that you can select some of the edges which are close together and double tap g to slide them over to nearby edges.  If you have 'AutoMerge Editing' activated, the overlapping vertices that result from this will be removed automatically without you having to repeatedly use 'Remove Doubles'.  Using these tools you should be able to clean up many of the rendering errors that are visible along the boundaries of the model.

That one vertex is still a problem but now it's only visible from the inside.

I was not able to repair this without Applying the Solidify Modifier.
The modifier is causing the vertices at the junction to be difficult(each of them has a 'virtual position' as well and this is causing some logical conflicts some of the mesh editing tools).  If you want to clean that area a little more then you should Apply the Modifier.

You should consider looking for an import option that can maintain quads, it will allow you to use a lot more of Blender mesh editing tools.

UPDATE:  After trying again, I was able to repair the inside areas without applying the modifier.  Using a combination of 'Join'j and 'Edges->Rotate Edge'Ctrl+e and sliding vertices with gg, the area can be fixed but it's a bit of a Rubik's Cube to solve.  When the Solidy Modifier causes one of the editing operations to go bonkers, use Undo and try adding or rotating a different edge.

I've posted a video to Vimeo that shows this in action https://vimeo.com/119991069


Moving Key Frames All Together One Time I always get this problem of moving all the keyframes all together. I have to go by each object and count the frames which is very difficult and time consuming.

My question is...Is there a way to select all objects and move all their KEYFRAMES at once in the timeline?

The dopesheet window is what you are looking for, it has a button with which you can manipulate only selected objects.


Naming for image sequence? I am working in compositor and VSE and find that Blender does not seem to understand image-sequences named like 120311_115058__001.jpg?
What are the rules for naming img-sequences?
Thanks

There should be no issue with such naming. As long as the end of the file name is that of the sequence, for exqample: xxxx_xxx_#### in which # stands for the frame number.

If you are importing into the VSE make sure you select all of the frames that are part of the sequence (press A).

As for the compositor use an Image Sequence node you just need to select the first image in the sequence. Then enable Match movie length and Auto_Refresh.


When in draw mode, creating lines/curves, how do I drop or finish the line? I can't find the right button or instructions on how to place this line into the frame. When using the pen tool, the object drawn automatically places once I release the LMB. However, when using the line tool, no button finishes the line editing. RMB only erases the line.


Making a bone match another bone's rotation on a single local axis I've been trying to solve this problem for a very long time, but I've only ever come up with partial solutions.
I'm trying to do the following—please use the example rig in the attatched file to follow along. The bones (from top to bottom) are "Head, Neck, Torso, Base." Head and Torso are parented to Base, Neck is parented to Torso.
I'd like bone "neck" to rotate on its local Y axis as bone "head" rotates on its local Y axis, regardless of what other rotations on other axes bone "head" may possess.
I'd like this to work even if bone "torso" or "base" are rotated as well—this is the part I get tripped up on. In whatever setups I've managed to create, rotating the bone "base/torso" makes the neck rotate too much, creating annoying artifacts.
Could somebody please present me with a solution to this troubling dilemma?

Did you mean to link a file?

The simplest thing to do is try a copy rotation constraint in local space.  For what you're trying to do, this sounds like good enough.  Here's how to set it up:

You can see that the neck, even though it has no transformation, is following the Y axis rotation of the head, regardless of rotation of the torso.

If you rotate head, the neck will rotate with it; if you rotate torso, the neck will rotate with it as well.  That means that neck might rotate too much for your taste, but then, you really have to put more thought into how you want neck to behave.  You could always use transformation constraints or drivers to rescale any rotation to a certain desirable range.

I said this was the simplest thing to do.  Copying rotation in a single axis is dangerous, because Euler angles aren't really cleanly divisible into axes: by rotating a bone in its Z and X axes, you can create Y axis rotation, and there are places where one axis of rotation seems to turn into a different axis.  This can create unexpected behavior and poor interpolation.  Copying rotation from a single axis is really only safe when both bones involve only ever rotate on a single axis.

What's better is to think instead about where you want your neck to face, and to use a locked track constraint (locked in Y in this case) to face that point.  But that requires rethinking the problem slightly.


Using drastically different scale sizes for different objects I'm making my first complex scene and am trying to emulate the size of real world objects. I have a pack and a sword, which will be the main focal point of the piece. The kicker is, in my mind's eye, there's a huge mountain in the distance. I want to put it in "real world" scale so it sells the the distance and size when I set the camera f-stops. If I set my scale to miles or km, it gets really hard to find the pack and sword in the view port after I scale them to size. How do I go about using different such drastically different units of measurement in the same piece?

You can use outliner to select object and then numpad period "." key for centering it on the viewport.


Baking in Cycles ver 2.9 issues Has anyone else had issues with baking a texture in cycles in the 2.9 version?  Whenever I try to bake the texture, it crashes instantly.  I tried it on a simple plane and cube thinking that my scene was too complex but it does it every time.  The last version of 2.8 still works great.  Is there a new setup, or will it be a bug fix in the future?

There is no such issue with me when i do baking :)
Set render settings to default (Supported , CPU) maybe you are using Experimental for GPU .
I had some Crashes when I was using Experimental for feature set
I hope this helps you
GL.


How can i add stylized cracks on my sculpture? How can i add cracks on my stylized game asset sculpture ? And how to get a good result without having to increase the polycount? Also how can i get a non-destructive workflow where i can continue to sculpt without the cracks and then edit the cracks?

Most artists are dragging an alpha of a stylized crack on their sculpture, you can find a set of popular alpha on the Gumroad page of Michael Vicente aka Orb here: https://gumroad.com/l/nOkHw
You will also need an high polycount to apply the alpha's details.

But the best way to apply cracks is by creating a mesh that you will use to cut your mesh with boolean, you will get more realistic cuts and non-destructive (with Modifiers and BoolTool brushes). You can use the BoolTool to work faster, you will have to select your crack mesh (completely closed) first then the mesh to cut and use the Difference operation.

If you use the Brush Boolean menu in the booltool you will be able to edit the cracks. Add an edge split modifier with a 30 degree angle to display your cracks correctly, sometimes the smoothing appears badly arround booleans.


How to bring back objects? I pressed unlink on a torus and it's gone. I've tried searching online but nothing has worked. any way to recover it? I'm pretty new to blender and this is really annoying.

control+z = undo a number of times etc/menu = redo also.
alt+h to reveal hidden if hidden.


Does CPU matter when rendering with GPU? A bit of context: I've got two graphics cards (not in the same build, my motherboard cannot support that), a GTX 1060 and a GTX 960. I use the 1060 for most rendering and gaming and such, but the 960 is just collecting dust. I'm gonna get a PC from my school that I want to install the 960 into and use it as a rendering machine, but of course since it's a school PC the processor will be pretty bad. Will this low-end processor bottleneck my 960's rendering significantly? Or will the difference be minimal?

No.  GPU rendering is just that.  CPU will have little to no effect - pretty sure.
I am a little hesitant if system memory plays a role if you run out of graphics card memory, that could be an issue, but I'm not sure about that.


How to easily toggle a Boolean property? I want to write a simple toggle for an existing UI Boolean property. Every time I run the following code Blender should either show or hide the name of the object in the Viewport, depending on the current state. It works fine, but I wondering if it is really necessary to to call the property 3 times for this easy task.

import bpy

obj = bpy.context.active_object

if obj.show_name == True:
    obj.show_name = False
else:
    obj.show_name = True

Is there a more elegant way to write this?

This can trivially be done as:

obj.show_name = not obj.show_name

Which basically says: if True, make it not True (i.e. False), else if False, make it not False (i.e. True).


Object is darker after joining it with another object just like it I tried to join these two boots and the child becomes dark?

I separated them from the legs and then remodeled them, flipped the boot to the other side, and reattached them.

It is likely that your normals are flipped. If you used the Mirror command, then it will have flipped them. To confirm if this is the problem, go into edit mode, open the N panel, and turn on Face Normals by checking the box under the Mesh Display tab.

If this is the problem, then you can recalculate or flip your normals by selecting the mesh in edit mode and using the commands under Shading/UVs in the T panel.


Why are the figer tips not moving with my hand in pose mode? May armature moves but the finger tips on the hand are staying in place.

I belive I have recreated the problem with the image above
Check to see if the finger tips are weight painted. Weight painting controls how a model's mesh is manipulated whenever bones are moved. This means if a mesh is not painted correctly, you will get issues like part of the fingers not moving with the rest of the hand.
When in "Object" mode, select your armature, then also select your mesh which contains the fingertips

Weight painting mode 101:

    Single bone's weight paints can be viewed with ctrl and selecting that bone
    Multiple bone's weight paints can be viewed with shift and selcting multiple bones
    this mode will show a heatmap showing the weight of parts of the mesh

        dark blue = weight 0.0 -> this part of mesh is not affected when the selected bone is moved/ will               stay in place no matter how the bone(s) are moved
        dark red = weight 1.0 -> this part of mesh will completely move with the selected bone

    click on the mesh to paint on weights for certain bones

For more reading, here is the Blender Weight Painting Manual
So to fix the fingertips, you would select each of the bones at the tips of the fingers indivisually and paint the tops red with a brush with weight 1.0. This should make the fingertips snap into place as shown below.

Once you've done this with each finger and its respective bone, you should be able to go into pose mode and pose it however you want without the issue

Hope this helps


Blender fold cloth/paper/rubber Any ideas/concepts/methods to fold a mesh in a zigzag shape?
My idea is too make it folding, somehow like a falling cloth but in a more clean? controllable zigzag shape.
I need this work in animation.

Created an animation by playing with shape keys (as in picture), but the animation looks stiff.

thanks.
I know, horrible grammar, peace!

Ended up with animating the curve using empty but in a reverse way. This mean I pose the curve in zigzag shape first then animate it to straighten shape.


How to cut faces away? I have a cube and I want to cut along an edge so that I can move a face away from the cube.

Basically I want to make a cut along the orange selected closed line and at same time keeping all the faces (I just want to be able to move away faces without deforming the cube).

Note that my initial mesh is just a cube subdivided once, but seems the functions are a bit bugged:

Here's what I tried so far:

Attemp 1

Vertex Edit mode -> Edge Select -> Select ring to cut and press V

Don't work here's the result:

Attemp 2

Vertex Edit mode -> Vertex Select -> Select vertices to make a ring and press Y

Don't work either here's the result:

In edit mode using “Face Select” select the four front faces. Press ”P” and choose "Selection" from the drop down menu.


Blender model deforms too much in unreal Alright so I created a mesh in blender (okay, i threw some crappy sculpt onto the UE manni, and drew over it)

I keep getting 2 problems.
Finger tips just go where ever they want.... Seems weird as they are weighted exactly to that section... And my character pulls his back through himself.

On these photos the left shoulder is set to ONLY be weighted to shoulder. And the right fades out into 1/2 across back. Results arent very different.
I also tried weighting back to the spine_03 that is right there but that REALLY pulled it making it pass the neck and everything.

Can anyone give some insight on how to straighten that out?

My FBX i made in blender is here:
https://drive.google.com/open?id=1-V...wbODXgvo79ds9h

Going in and setting all the weights to a much smoother rate of change, and removing some from the auto weight option cleaned this up.


Is it possible to attach an object to the end of a curve and have the object point in the same direction as the end of the curve? I've come up with a few ways to do it but they're all hacks, and none of them work with the build modifier.

I want something that will keep the object at the end even when the build modifier is being used so that the object seems to move along with the curve.

I was wanting to make something that looks like this:

That way the cube is pointing along the curve no matter how the curve shape is modified. This seems like something that blender should be able to do on it's own.

You can do it with a little trick.

Create the cube and the curve
Create a plane at the exact same position as the cube and scale it down so it is inside the cube. Do it in edit mode so that its object scale won't change
Parent the cube to the plane
Mark the plane as dupliface in the instancing section
Add a curve modifier to the plane

This is the start of the curve, though...

Edit: to do it at the end of the curve

Parent the cube to the curve
Set the curve as 'path animation' with only 1 frame
Adjust the cube orientation so that it fits the first control point of the curve


How to "unlink" bone? I've been following along in a tutorial on animation and I must've inadvertently clicked on something because I've animated a part of the model that shouldn't be attached to a bone/armature. (Notice the double rectangles to the upper left of the robot head. These are part of the robot's head, and should remain fixed to the head, but instead they're animated along with the arms).

How do I "unlink" the "head" element(s) in question so that they stay fixed?

Also, I've now just gotten into a state where I can't select anything. The properties area is now all about armatures, and I can't see/recover the "normal" tool icons like "wrench" (for boolean operations, etc.) or "sphere" (for materials, etc.), so I can't do "normal" editing operations.

Here is the file on GitHub: https://github.com/DragonForest/first-robot.

Thank you!

In Edit Mode, select the Bone and press W

You can switch the bone direction and others


Shrinkwrap or Skinwrap modeling technique? I heard about this technique on a youtube video but when i tried to replicate it it just doesn't work. Essentially the technique consists in model different hard surface parts and then smoothly join them together only with the shrinkwrap modifier instead of boolean the parts and retopologize everything. Here the video, the technique i'm talking about is at the min 16:04
https://www.youtube.com/watch?v=oJbxu_GLMz0&list=WL&index=1&t=1145s
I tried but the final result it wasn't like in the video despite having followed the same process that is just apply the shrinkwrap. Does someone know anything about it? .

Not sure exactly what you did, you should show some images of your project.
I tried and it looks like the example, he also said that he needed to make some adjustments before the "Apply" to get what he wants.
Just the shrinkwrap modifier with a Wrap method in "Project"


python : creating 4D simplex by connecting all vertices with ever possible triangular face I'm creating higher dimensional shapes (4+ dimensions) and for a simplex, every vertex is connected so that any 3 vertices you pick form a triangle. this is simple to do with shapes with a low vertex count but the face count grows exponentially as the vertex count goes up to the point that a simplex with only 32 vertices would have 4960 faces.

Doing this by hand would take forever so what I'm looking for is possibly a python code that would make a triangle face between every possible group of 3 vertices in an object.

Alternatively, I don't necessarily need all the internal faces, just the internal and external wireframe, since I'm not using glass refraction, I'm just using transparent faces with gloss. Really I just need the external faces visible and all the lines visible with the wireframe modifier. I tried just making a wireframe model and putting the wireframe modifier and having a separate mesh shrink wrap to it for the external faces, but unfortunately both those modifiers only work based off faces rather than just lines and verts so if there are any work arounds that would fit this method I'm open to hearing that too.

4-simplex or 5 cell

Bmesh Script

Result of running on 9 vert circle, without faces

Test script to run in edit mode.

removes all edges (and henceforth faces) of mesh
adds an edge from each vert to every other vert
if make_faces is True will add a face for each set of 3 vertices

import bpy
import bmesh
from itertools import combinations as combos

make_faces = False

context = bpy.context
ob = context.edit_object
me = ob.data
bm = bmesh.from_edit_mesh(me)
# remove edges and faces
for e in bm.edges:
    bm.edges.remove(e)

edges = [bm.edges.new(c) for c in combos(bm.verts, 2)]

if make_faces:
    [bm.faces.new(c) for c in combos(bm.verts, 3)]
# str(bm) for total verts edges faces
print(bm)
bmesh.update_edit_mesh(me)


Why my object change material when using node shading I made a simple object (one cube) and assigned the color to face that i wanted as follow (photo 1)
I turn on the "use node" in material tab and named it "Top and Bottom" respectively
Then I opened node shader and click the material slots
The material previewed in viewport interchangeably as I click different material slot in node shader. (photo 2)
If I bake while this happened, it's directly bake like this (photo 2)

I'm not understand why it happened even though I assigned the material? Is this normal? Why it happened?

enter image description here

Hope it'll help somebody out there, i already found the answer after messing around with it. So here what I found
Clicking on the material names in the node editor will also change the material of whatever is currently selected (or the group of vertices that have been assigned that material).
If you want to edit different materials in the node editor that are all part of the same object you can use the "Slot 1" and "Slot 2" options to the left of the material name.
TLDR; it changes if you select (material icon), it'll changed whatever the material. To change anything in node for material (in green box). It'll make the baked texture remain as intended.


How can I simulate powder with a particle system? I want to simulate powder, are particles the best job for this and if so what settings could I use to achieve this in Blender?

Particles:

You could use Newtonian or Fluid type Particles to simulate the powder, with the gears and funnel as Collision objects.

For example:

Add a plane (ShiftA> Mesh > Plane) and add a particle system to it.
Set the Lifetime to a number greater than the scene End frame
Set the Physics to Fluid in Particles > Physics
Add an Icosphere (ShiftA> Mesh > Icosphere). You may want to set the Subdivisions to 1 in the Redo panel or the F6 menu for situations with many small particles.
Set the particle Dupli Object to the icosphere in Particles > Render > Dupli Object
Set the size in Physics as desired, I used .001
Enable Simple in Particles > Children and set the Radius and Uniform Roughness as desired.

The Radius defines how far child particles are allowed from the real particle
Uniform roughness gives some randomness to the locations of child particles

Set the Cache Step in Particles > Cache to 1, this will record the location of each particle every frame. The default of 10 often gives strange results.
For object you want to collide with the powder:

Add a Collision physics modifier in Properties > Physics
Increase the Particle Damping factor. By default particles will bounce very high, this setting controls how much velocity the particle loses on collision with this object.

Bake


Compositor - How to math same Result for any Render Size Any time I change Render Size it ruins all my node-tree setup.
Common workflow in compositor is to work in some lower resolution to set wanted effect. Like 50% or 25% of final size.
But many values are based on current image size on input.

Does exist any math combination that can be applied to a node-tree to protect result? A math that equally increase or decrease values in one place?

In this gif example is used the same node-tree to generates lens flare.
Rendered on 10%, 25%, 50%, 100%

The current compositor is not relatively aware. Hence some pixel based nodes give different on different resolutions. There is a new design for the compositor that will overcome this issue, but this still needs a lot of development time. https://developer.blender.org/T53790


How to order a list of vertices based upon position? I have a list of vertices:

But the list looks like this: [0, 1, 2, 3, 4, 5, 6, 7].

I need a script to sort the list to be like the order in the loop itself: [3, 2, 1, 0, 4, 5, 7, 6].

What list are you referring to?

the numbers shown in the image are indexes of each vertex in the obj.data.vertices list; a list of these indexes: [0,1,2,3,4,5,6,7] (8 vertices).

In the edges in obj.data.edges list you'll find the indexes of vertices that define the edge; sample: [[0,1],[1,2],[2,3],[0,4],[4,5],[5,7],[6,7]]  (8 edges).

It feels like you want to reorder edges so you can loop them based on their index in obj.data.edges; sample: [[3,2],[2,1],[1,0],[0,4],[4,5],[5,7],[7,6]].

In that case you'll need to search for a start vertex the loop. A vertex which belongs to only one edge is a fitting approach. There are 2 of those in your sample, in this code the first appearing in obj.data.vertices list is selected:

vecount = []
for e in obj.data.edges:
    while(len(vecount)-1 < max(e.vertices[0], e.vertices[1])):
        vecount.append(0)
    vecount[e.vertices[0]] += 1
    vecount[e.vertices[1]] += 1
startidx = vecount.index(1)

Now obj.data.vertices[startidx] is the starting point of the loop
Now you can create an array of edges, sorted from starting point towards end point:

edges = []
doneidxs = [startidx]
curridx = startidx
while (len(doneidxs ) != len(obj.data.vertices)):
    for e in obj.data.edges:
        if e.vertices[0]==curridx or e.vertices[1]==curridx:
            if not e.vertices[0] in doneidxs:
                toidx= e.vertices[0]
                break;
            else:
                if not e.vertices[1] in doneidxs:
                    toidx= e.vertices[1]
                    break;
    edges.append([curridx, toidx])
    doneidxs.append(toidx)
    curridx = toidx

Now you can apply the new order of edges by updating vertex indexes in the edge vertices arrays:

for e in obj.data.edges:
    e.vertices[0] = edges[e.index][0]
    e.vertices[1] = edges[e.index][1]
obj.data.update()

Run this code having the mesh selected (3D View, OBJECT mode), starting with pointing out that's the object you want the code to work on:

obj = context.active_object
...(above code)...


How can a blender driver python script access scene properties like FPS? I would like to be able to access properties of the current scene such as render.fps, frame_start, and frame_end from within a python driver script.  I have some data that is defined in terms of seconds, and I'd like the drivers consuming that data to work in two different scenes which have different frame rates.

edit: I tried using bpy.context.scene, but it turns out that is often wrong.  Let me be specific:  The driver is being evaluated to calculate the position of an object in scene "cave" and bpy.context.scene refers to scene "splash" .  In a 1-scene .blend bpy.context.scene works fine.  In a multi-scene .blend, bpy.context is not necessarily populated with what a reasonable person would consider 'the context of the driver'.

Inside script editor define your own function and register it for driver use:

import bpy

def driver_fce():
    scn = bpy.context.scene
    # You can use here:
    scn.frame_current
    scn.frame_start
    scn.frame_end
    scn.render.fps
    # etc..

    return 0    # some value

# Register it to driver namespace under name 'driver_fce':
bpy.app.driver_namespace['driver_fce'] = driver_fce

Use it like this:

Note that such drivers on node properties do not update correctly and its better to use frame change callback handler instead in that case.


Faster Process suggestions for Interior Renders I'd love to get pointed in the right direction on this. I need to make some interior renders for a project at work, but my process has always involved unwrapping and then texturing. But it'll be 80% concepting and idea generation, so I would need to model soooo much crap and that process seems so backwards in this time crunch! The Uv and texturing portion is what Im slowest at , wondering if there is a decent process that can skip alltogether or drastically speed that up.

I dont need to go for insane photorealism. Would nodes be the direction, or some other trick or method I should pursue?

If you are creating scenes multiple times, each with similar ideas/looks, why not create an asset pack?

Firstly, create your tables, windows, chairs, vases, couches, curtains, etc. and put them on a single .blend file, group them by object type, then import the file whenever you want to use them. It saves loads of wasted time.

Secondly, You may know this already but I'm going to mention it just in case. Use the boolean modifier for windows. It's a time saver. This is a great thing to use on the asset pack windows as well.

Thirdly, if you don't want to use an asset pack and need to create unique objects whilst cutting back on time, create objects with single colours or built-in textures like noise. This often means you do not need to worry about UV unwrapping. This though may not be what you are looking for but it is quite a viable option.

Fourthly, whenever possible, keep your objects in a cube-like fashion. UV unwrapping becomes 100X easier. Plus, when your items are like this, you can use smart UV unwrap and it normally works a treat. If your meshes become complex, take a look at the decimate modifier. It may help, or it may not.

Fifth, Create all your models, then texture. I know this may sound stupid and people will argue with me on this one. I find this something of personal help. It may work for you, it may not. I just find that you can keep yourself in the modelling headspace much easier if you're not switching between two tasks. Plus, if you find an object doesn't quite work with the scene, you don't have to re UV unwrap it when you're done. 'OHH, but it's not the same without colour'. That, my friend, is what my recommendation 3 is for. Add solid colours before you texture. Ensure everything works well together.

Sixth. Simple but helpful. Use backface culling on the walls, floor and roof so you can see your scene from the outside.

Finally, use the mirror modifier. The number of times I see people using the mirror modifier to create their object, to only apply it and UV unwrap the whole mesh. If you have used a mirror modifier, or can use one, it can halve the time spent on each object. Even if you need to texture each side slightly differently, (the left handle needs to be blue, the right red) still UV unwrap with the mirror modifier. Once you have unwrapped, apply the modifier and both sides UV will appear on top of one another. Move the handle to where you want it.

Tadaa, Seven wonderful tips, as you requested :P

You may use them, you may not, but all my recommendations are up to the preferences that suit the user.

BTW, I would love to see a render of your scene when you are done. I love the look of interior designs :D

Good luck with your project and I hope I helped,

BFB

Quick afterthought:

If you want quick, less realistic renders and the option to look in realtime, I recommend checking out Blender 2.8 and its new feature EEVEE.
It does take a while to get used to the new interface and it is still in production, riddled with bugs, but for what you are doing, I believe it will help you allot, particularly with texturing.


Selecting a specific cube in an array to change properties I am trying to iterate over an array of cubes that I created and assign a new location to each one. I am having trouble with my iterating code. I know the issue is somewhere in how I am referencing each cube.
import bpy

cubes = []
for i in range(10):
    cubes.append(bpy.ops.mesh.primitive_cube_add(size=1, location=(i*2, 0, 0)))

for cube in cubes:

    cube.keyframe_insert(data_path='location', frame = 1)
    cube.location = (10,0,0)
    cube.keyframe_insert(data_path='location', frame = 120)

This operator does not return a reference for the created object.,
bpy.ops.mesh.primitive_cube_add(size=1, location=(i*2, 0, 0)))

so change to the following.
bpy.ops.mesh.primitive_cube_add(size=1, location=(i*2, 0, 0))
cubes.append(bpy.context.active_object)


Modelling a twist like this procedurally I'm trying to achieve more or less this kind of twist on a model, but I want to do it procedurally rather than by hand. How would I go about this?
Picture for reference:

Thank you in advance!

As you suggested, you can use Simple Deform modifier for this

One modifier set to Twist for the spiral
Angle around 1080° for three twists, and use limits to move it up/down
Second modifier set to Taper, and adjust to your needs.


How to limit the rotation of a bone in an FK chain? Im using metarig to rig a model of a robot and the arms and legs have brackets connecting the joints where rotation in a certain axis would cause part of the model to twist into the mesh of the bracket. To stop this from happening I want to limit the rotation of the middle FK but after messing with every possible combination of constraints and rotation locks I still cant get it to work. I have attached an image of the arm I am working on.

just add the limit rotation bone contraint to that bone, and uncheck the axis that you wont use and then play with starting and ending rotation, for example if you want it to have a limit of 90 degrees just add 0 deg as starting and 90 as ending and thats it.


How to make a game autosave and autoload I need my game to always save all settings and scores, also always load them when running game. And... I want to also save theese objects, which has disappeared from scenes(collected points, boost ups, etc.) Who can help me, please?

There's probably a much easier way, but you could have variables which change depending on what level your in ect, along with others that toggle the use of boost ups and collected points etc. Then you can save these variables to different .txt files so that they're the same when you start up the game next time.
For Python Variables:
Connect this script to a keyboard sensor, with a status of All Keys, followed by an always sensor. The pytho controller is in module mode. You need a folder next to the .blend called "SaveLoad". And finally add two game properties to you object just so that you can see that the script really works.
S Key to save, L Key to Load and A Key to change the variables, but obviously you can easily modify the code to you needs of automatic execution.
import bge
from bge import logic
path = logic.expandPath("//SaveLoad/")

cont = logic.getCurrentController()
own = cont.owner
keys = cont.sensors["Keyboard"]

var1 = 20
var2 = 60

def save():
    global var1
    global var2
    for key,status in keys.events:
        if status == logic.KX_INPUT_JUST_ACTIVATED:
            string = bge.events.EventToString(key)

            if string == "SKEY":
                info = str(var1)+","+str(var2)
                file = open(path+str(own)+".txt", "w")
                file.write(str(info))

            if string == "LKEY":
                file = open(path+str(own)+".txt", "r")
                line = file.readline().replace("\n","").split(",")
                var1 = int(line[0])
                var2 = int(line[1])

            if string == "AKEY":
                var1 += 1
                var2 += 2

    own["prop"] = var1
    own["prop0"] = var2

For Game Properties
This script needs to be set up the same way as the variable script, but yet again you do have the option to change it to your needs.
from bge import logic
path = logic.expandPath("//SaveLoad/")

cont = logic.getCurrentController()
own = cont.owner
keys = cont.sensors["Keyboard"]

### Use keyboard
for key,status in keys.events:
    if status == logic.KX_INPUT_JUST_ACTIVATED:
        string = bge.events.EventToString(key)

        ### Save "prop" and "prop0" to file
        if string == "SKEY":
            info = str(own["prop"])+","+str(own["prop0"])
            file = open(path+str(own)+".txt", "w")
            file.write(str(info))

        ### Load "prop" and "prop0" from file
        if string == "LKEY":
            file = open(path+str(own)+".txt", "r")
            line = file.readline().replace("\n","").split(",")
            own["prop"] = int(line[0])
            own["prop0"] = int(line[1])

        ### Change values
        if string == "AKEY":
            own["prop"] += 1
            own["prop0"] += 1.3


Smooth Shading distorts mesh? Why does this happen to my object when I apply the smooth shader and how can I fix it? I am working with a low poly mesh, or at least trying to keep it low poly but, I would like it to look smooth and not jagged. Each time I use the smooth shader it completely distorts the mesh. Do I need more faces? How can create that without using the knife tool? Thank you for any input.


Alpha rendering with White background I have applied a material and texture to a blender mesh. It renders in the 3D view with a white background in the texture paint mode. Is there a way to show the transparency correctly in this view?. Having read posts on the internet about rendering alpha, suggestions were you need to:
1) Ensure the texture is set up to influence the alpha channel (which it is)
2) "use Alpha" is ticked in the texture image options
3) Material is set to "Z transparency", with an alpha and specular value of 1

In the material window, you can see the transparency working. However in the 3D texture paint view, it shows as a white background.

Thanks,
Mark.

Does it help if you switch the shading of the 3d view to GLSL? You can switch between "Multitexture" and "GLSL" in the properties panel (open with N key in the 3d view), under the "shading" group. Material alpha should be 0, and texture alpha influence > 0 (texture transparency shows transparent in the material) or <0 (the inverse of the texture transparency   shows transparent in the material)

See this example:


What is going on with the Extrusion? Hi so I am currently creating a Witcher Wolf School Medallion just for fun, However it's decided to do this with the last extrusion. I saved before this happened so I've being unable to fix it.

What is this and is there any way to fix it? I appreciate any help given!

Gemma

By default your extrusion will follow the normal of your face, so if your face is slightly tilted on the Z axis it won't follow the Y axis. If you want your extrusion to follow the Y axis, you need to constraint the extrusion: press E to extrude, then Y. Also don't forget to activate the Clipping option of the Mirror modifier, it will prevent the creation of any inner faces.


Delete all scale animations from specific animation Is it possible to somehow delete all scale animations from a specific animation?
I am creating animations for unity, and in unity I get alot of warnings if I use scale animations, because they cost much performance.

Sometimes I accidentally add scale animations, then I have to find the specific bones and delete the scale animations on them one by one.

Is there a faster way, maybe a script?

Select all bones/objects
Open Graph Editor or Dope Sheet
Type "scale" in search bar
Select all keyframes and delete


Is one sample rendering in Cycles sufficient for a simple texture shot? A scene to produce a 2D texture image (for use in another scene) consists of one camera and one rectangle. The rectangle uses only one shader - Emission.  The Emission's color and strength are controlled by a fancy nodes setup using images and perlin noise.  There are no diffuse, glossy or other shaders. Just Emission. There are no other objects in the scene, nothing to bother rays/paths between the camera and the glowing rectangle.

Do I need to render with multiple samples?

Of course, I did the obvious and set Cycles' Render Sample to 1, and the result looked fine. But maybe I have a quirky scene that happens to do that.  There doesn't seem to be any sources of randomness in calculating any one pixel again. Rendering with hundreds of samples is necessary only if there's scattering such as with Diffuse of Glossy.  Am I right?

As cegatron mentioned, if your happy with the result then you only need one sample. Something to consider is that one sample also effectively eliminates anti-aliasing.

By choosing Branched Path Tracing you can also get more control over the samples used. You might have a scene that uses SSS so you can increase the subsurface samples but keep the glossy samples at one.


Making a scene, using Blender render but want to add tree's that are done in cycles I Making a scene, have already put a lot of work into it. Little town, with model T car's and misty mountains, using a lot of lamps. I wanted to add tree's to the scene and learned how to do them in cycles, but cycles is not working well in my scene. Is there a way I can create tree's without cycles or away I can link in the cycled tree's into scene and render it normally?

Perhaps you could add a tree image with a transparent backdrop. Then in the nodes remove the backdrop with a transparent node, and apply some different shaders such as specular and bump or normal maps to give the realism effect. This is what is used in most games as it uses minimalist faces which saves time in your final render, However they are used for distance scenes. This is the only other way of creating a tree that i can think of without creating a 3D tree, whether that be sculpted or generated with the Tree plugin.
Hope this helps Mate.


Bevel Tool not cutting evenly Does the Bevel Tool only evenly Bevel if the object is a pure cube or square?

My Bevel Tool currently only cuts into one face, at a sort of 5-1 ratio rather than an even spread.

In this example, I want the bevel to 'corner off' the, well, corner. As marked in red.

I'm a newish modeller and it's possible some settings are scrambled or something.

Thanks!

You have a couple of coincident edges.

If you start with an edge close to the corner, the bevel will be clamped on one side (left and middle, below). If the edge is slid all the way down so you can't see it, the bevel will only happen on one side (right).

Note, if you're in Face selection mode, and you have face markers switched on, you can see the scrunched face .. it's the dot in the middle of the corner edge.

Solution: Remove doubles (2.79: CtrlV,R. 2.8: AltM Merge > 'By Distance')


Why are these mesh white and does not appear in rendering? I'm trying to edit this intro https://www.youtube.com/watch?v=fya4qXcCzeU, but the mesh contained in the intro does not appear in rendering, the mesh appears all white in preview.

In the video contains the link with the file blender.

Thanks to all who tried to help me

Cheers!

While you are in Object Mode press W and then Clear All Restrict Render. Hope it helped


knife_project in python I am a blender noob trying to use bpy.ops.mesh.knife_project() in my script. It fails with the message:

  RuntimeError: Operator bpy.ops.mesh.knife_project.poll() expected a
  view3d region & editmesh

Already tried this method. It fails with the same message

Here is the relevant part of my code. insulator is the active mesh object. knife is the curve object to be used as knife.

knife.select = True
insulator.select = True

override = context.copy()
for area in bpy.context.screen.areas:
    if area.type == 'VIEW_3D':
        override['area'] = area
        override['space'] = area.spaces[0]
        for region in area.regions:
            if region.type == 'WINDOW':
                override['region'] = region
                break
        break

bpy.ops.view3d.viewnumpad(override, type = 'BOTTOM', align_active = True)
bpy.ops.view3d.view_persportho(override)

#bpy.ops.object.mode_set(mode = 'EDIT', toggle = False)
#bpy.ops.mesh.select_all(action='DESELECT')
bpy.ops.mesh.knife_project(override, cut_through = True)

The view changes to bottom and orthographic view, but the script halts at knife_project.

The blender python reference gives very little information about this function.

Any ideas?

You walked in right direction, but the code should be wrapped in operator execution method, register and call it from Operator Search using chosen view.

I've made this gist from operator_simple.py template, it works from object or edit mode with active object as target and other as knifes.
https://gist.github.com/Begalov/763688551b49004d92ef227ddd7694d6


Normal map when painting in blender I am painting a model using the texture paint tool.  I am painting the diffuse of a moss texture onto a building I created.  I also have a normal map that goes with the moss texture.  Is there a way for me to recover the UV coordinates that are being generated when I paint my model.

There must be some mapping between what is appearing in my texture that I am painting and the texture attached to my brush.  How can I recover these coordinates so that I can use them to generate a normal map?

Regards,

Final result:

Overview:

As far as I know there is no way that Blender could generate normal map from diffuse map.

There is similar approach to what is going on in software like Substance or Quixel but it is painfully manual and not such fun.

In those apps you generally paint by stacking materials on layers and mask them one by one; and this you can do in Blender as well.

Steps:

You will need both Diffuse and Normal texture for both materials and created texture for painting Mask.

Node setup:

Texture Paint:

Set Slot to Image, choose your mask and start painting.

Final thoughts:

This is not ideal method especially when you need more layers/masks, this is why more and more people looks at software mentioned above (including myself).

There is another approach I can think of. You can paint your diffuse, then export it and generate Normal map in chosen app, then load it to Blender.

Blend file (textures packed):


add object at specific location with python? This might be a really stupid question-I'm working in bpy right now and want to add a plane at a specific location...I know that How to add an object at a specific posistion in Blender Game Engine works for bge but am not sure if it'll work in bpy...

The tooltip of the Add > Mesh > Plane menu path shows this information, press Ctrl+C to copy it to clipboard.

Tooltip

All of these menu items trigger operators and take several optional arguments, location=(x,y,z) included. The same applies to the other items in the Curve, Surface Metaball etc., menus.

Docs

The total list can be found in several locations, in the docs

Blender's Python Console

use the auto complete feature (ctrl+space) in the Blender python console after typing bpy.ops.mesh.primitive_

The arguments to the bpy.ops.* can be found doing auto completion too

Info Panel

You can see the history of most of the code which has been triggered in the UI, in the Info panel if you drag it down


Online colour grading LUTs So, I was researching some stuff about colour transforms, and found some companies who sell colour grading LUTs.
They did include with the free samples a set of transforms from a bunch of recording formats to rec709, so that the grading LUT will be applied to a rec709 input.

I wasn't considering buying, but I was wondering how useful these would be. Given the expected pixel output 'x' depends on the transform performed on a given pixel input 'y'. Can we genuinely expect 'x' out for any 'y' put in after the conversion to rec709?

If I have recorded for example, Alexa Log-C or RED Log, can I reasonably expect that my Alexa Log-C or RED Log pixel is the same as someone else's Alexa Log-C or RED Log pixel, to convert to rec709 and from there to an orange(or teal) 'film look' pixel?

You absolutely nailed it; they are a load of codswallop and rubbish.

The bottom line is that all colour transforms are based on a chain of assumptions. The moment a single assumption is wrong, or a single transform is out of order, the whole stack becomes invalid.

TL;DR is you can trust the transforms if you know they are the correct ones and they are / were applied properly. However, I would be at least as skeptical with purchased LUTs as one should be with HDRIs; prepare to be underwhelmed at best, and outright scammed at worst.

Fantastic question and welcome to the forum.

;)


Selection based on UV and Texture Edit : The script work, I was using the wrong texture.

following my previous question, I'm working on selecting vertices in edit mode based on the UV coordinate and a grey scale image.

Here is my script at th moment :

import bpy
import bmesh
import math

obj = bpy.context.active_object
me = obj.data
bm = bmesh.from_edit_mesh(me)

bpy.ops.mesh.select_all(action="SELECT")
bpy.ops.uv.select_all(action='SELECT')

uv_layer = bm.loops.layers.uv.verify()

uv_name = "MyTexture.png"
tex = bpy.data.images.get(uv_name)
pixs = tex.pixels[:]
texSize = tex.size[0];
# adjust uv coordinates
for face in bm.faces:
    for loop in face.loops:
        loop_uv = loop[uv_layer]
        x = math.trunc(loop_uv.uv[0]*texSize)
        y = math.trunc(loop_uv.uv[1]*texSize)
        if ( x >= 512) : x = 511
        if ( y >= 512) : y = 511
        value = pixs[((y * texSize ) + x)*4]
        if(value < 0.5):
            loop.vert.select = 0
            loop_uv.select = 0

bmesh.update_edit_mesh(me)

For some reason it lacks accuracy as some vertex who are too close from white pixel but are on black pixel are selected :

I thought it was the trunc operation but changing it to a ceil or round didn't change the lack of accuracy.

Any help is welcome.

I was using the wrong texture, the script works fine.

I was loading the wrong texture in the script and looking at another texture in the background of my UV editor.


My object is smooth in solid view but not in rendered mode In solid view, my object's smooth however in render mode it's not. What's the problem?

Solved! Just increased value of view in render in subdivision surface modifier


Objects From Group, list order issues - Animation Nodes I run Animation Nodes to drive shapes on a rig with bones - such a better solution to Drivers.

But currently the shape Group list I use to select that particular object (needed for updating the rig and keeping the group relatively dynamic)gets the object list order mixed up sometimes.

Why does this happen? Is there a way to sort the group object list order with Animation nodes?

If you have a list of object [Object B, Object A, Object E, Object C, Object D] and you wish to order them as [Object A, Object B, Object C, Object D, Object E], simply construct a list such that its elements are that of the list at the indices [1, 0, 3, 4, 2].


Cannot duplicate metaballs I made a little cloud using Metaballs:

I would like to duplicate the Metaballs to a different layer to back up this cloud, then convert the main layer's Metaballs into a mesh.

When I select the Metaball objects and duplicate them to another layer, they remain on Layer 1 and the elements copied onto the other layer have no mesh:

This is what gets duplicated and moved to Layer 2.

Meanwhile on Layer 1 the duplicated Cloud on the right has not been moved to Layer 2.

So obviously there's got to be another way of doing this (maybe I convert the Metaballs into a mesh, copy the mesh, then Undo conversion? Or duplicate the Blender file).

I'm just trying to work with Metaballs in a non-destructive way to go back to my Metaball setup if I need to.

How Metaballs Works

A metaball object can contain multiple metaballs which you can add in the edit mode of the object, all metaballs in the same object tend to be polygonized together, that is, they combine forming a single mesh. Moreover, if another metaball object that possibly contain multiple metaballs have the same "predot" name (Object, Object.001, Object.002, ... all have the same "predot" name), it will also be polygonized with the metaballs of the original object and thus it becomes part of the output mesh. All metaballs that form a mesh are called a Family.

If a metaball was created outside of the family (by having a different name), it will no longer polyginize with the other families and will only polygonize with members of its family. So you see that naming is crucial in metaballs.

Solution to your problem

All your metaballs have the same name even the ones you duplicated, thus they belong to the same family and they polygonize together forming a single mesh. When you move the duplicated metaballs to a different layer, blender has to decide which layer to put your generated mesh (Because it is a single mesh since it is a single family), so it just put it in the layer where the base metaball is, the base metaball is the object with pure name, that is, a name without numbers (Object in our previous examples.)

So to save a backup version of your metaball, simply change the name of its objects.