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How to make an animated blob?
Ok, I have never done any deforming/shape blending, and Ive been working primarily in Maya here but I thought you guys on Blender exchange might be able to put me in the right direction.
Im very new to 3d and I need to make a shifting blob - essentially taking 2 spheres that have to be 1 object (HAVE to be combined or just 1 object, its crucial for putting it into Unity) and moving them around within each other to make it look like a cartoon cloud.
I watched several tutorials on shape blending as Ive found out that this means distorting objects in an animation, but most of them deal with stretching 1 shape or face, not making bulges/moving around other shapes.
This is what I have in Maya (I could do it in Blender also) but when I go to Deform->Blend Shape, it won't let me create an animation because the last 2 shapes were created by combining 2 spheres.

I just need to bulge a sphere in an animation to import into Unity. I have no idea where to go. How can I do this?

If I got what you need, you should be able to achieve this using either a single object made by 3 separated spheres, animating them as shape keys (https://www.blender.org/manual/animation/shape_keys/introduction.html) but I don't know about how Unity will like shape Blender keys animation.

Why not just have it as three individual animated objects that share the same material? You could also do this with Metaballs although I'm not sure about the transition to Unity in that case. Collada might manage but I don't think so.

Because I have a transparent material and overlapping makes it look bad.

Have you tried using shape keys?


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Can't bake Cycles material to texture - "no active image in materials slot" or bake doesn't work?
Ok, Ive looked everywhere for this and tried following solution explained here - Export cycles material to unity
in order to make my MATERIALS (I don't have textures - just basically diffuse materials that Id like to preserve in color/roughness/low poly look) when exporting to dae for use in Unity or Xcode.
If I try to bake without following the steps above I get error - "no active image in materials slot". But right now the bake turns black.
I followed everything mentioned and learned to preserve my material I need to bake them to textures - so I

created a new blank image in UV editor
unwrapped "U" my object to the image like here: (color doesn't come thru to image but I assume thats ok?
Set Bake settings like this:

Here is the material Im trying to get to stay put as its color/diffuse/etc once I export to dae:

And the results are all wrong. Textures are weirdly transparent and baking hasn't affected anything:

What am I doing wrong here? Ideally Im trying to go the easiest possible route keeping my MATERIALS going to Unity/xcode. How can I do this? Desperate here

You shouldn't worry about how your materials will look in Blender, they will be completely different on Unity because the shaders and rendering pipeline is very different. The right approach is to assign simple materials in Blender (so you just see which is which) and only fine-tune the ones you assign in Unity.

Guessing a bit, but for this to work, you need to have an active (i.e. selected) Image texture node in the node editor. Did you remember to select it (make it active) before hitting Bake?
Also: I see you have selected multiple passes to bake. I think you need separate textures for each. (Select an image in the texture node, make sure it is still active, select a Bake type, hit Bake.)

Can you show a picture of an example of making it active? Im new to blender..

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can you have two brushes in dynamic painting?
Not getting the other brush to function , my question is that can you have two brushes in dynamicpainting painting the same canvas. ?

Yes, you can.
... "any" number of mesh objects (set as Brush) should work for the same Canvas object.

Blender Manual for more info check Dynamic Paint
When you have any issue, it is always good way to open a new file and test it with maximum of default setups, if still issue "Load factory settings" and test again.
BTW answering given Q didn't move you forward and didn't solve your issue ... try to edit your Q with something more specific that we can solve for you :)

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Star Trek tractor beam effect
I am trying to create the tractor beam effect from Star Trek. I applied an emission shader with a noise texture as the factor and set the scale on the x channel of the texture coordinate to 0. That got me close. I thought if I applied this material to a cylinder then scaled one end of it down I would be done. However I get the following effect.

Can I adjust the coordinates so the rays come together at the top? Is there a better way to get this effect? I want to use it in an animation which is why I used the noise texture. By animating the texture coordinates I can get the rotating beam effect you see in the series.

Use a volume, a mesh to block some of the light, and a spot lamp. Will write an answer ASAP

@user1509130 Did my answer address your issue? I'd appreciate it if you'd accept it if it did.

This  is written for Cycles, however the same steps apply for Blender Internal except you do not need the volume mesh. All steps including the shadow mesh and lamps are the same.

I would recommend using a cone shaped mesh set to volume, a mesh that has holes in it to give the beam shadow, and a spot lamp. Start by adding a cone to your scene using Shift+A > Mesh > Cone:

Now move it, scale it, etc. as desired and add a spot lamp using Shift+A > Lamp > Spot and move it to the top of the cone.

Now change the cone material to have a Transparent surface material and a Volume Scatter volume material in the material settings:

Now all you need to do is add the texture to the volume. I do this by adding a plane, subdividing, and then deleting some random vertices:

Now move it into the beam of light, rotate, duplicate, etc. and tweak the lamp settings and position as desired. You should end up with a result like this:

I have included the .Blend file for you to examine and compare with.

Shape key animations on the greeble prop may help to get the twinkle effect for the beam as time passes.

Good idea! Also, animating the position of the various layers can give a good result as well.

Maybe the random f-curve modifier?

You can use the select random feature to select the vertices to delete, it's just a tad faster.

Sorry this took so long. Got busy with school and haven't been able to get back to this. That is the best solution I have seen so far, and much different technique than I have been trying. It does fade out the further you go, but that may actually make it look for realistic than the original effect. Thank you!

No problem, glad to see you back

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Emission shader color saturation clipping
I stumbled on a trick that while working on one project that will help me with another, but I am not sure why it works.
When I set the color of an emission shader to a saturation of 1 the shader appears that color no matter how strong the brightness is set to. However, if it is set to about .85 or lower, the shader becomes white when very bright much like a light would be in a photo. When you apply a glare filter to the output the glare is the color of the emission node while the object itself is still white.
I understand why this would happen in camera, clipping and all of that. What I don't understand is why this happens for lower saturations in Blender and not higher ones.

I have noticed the same thing, I'm curious as well!

Easiest to explain it with an example. Let's take fully saturated blue. At power 1.0, that is RGB 0.0, 0,0, 1.0. Let's boost power up to 2.0. We now have 0.0, 0.0, 2.0. This can't be display on our monitor, so it clips to 0.0, 0.0, 1.0. Essentially negating the power increase. We have the same blue we started with.
Now let's try 85% saturation, but still at full brightness, emitter power=1.0. That's RGB 0.15, 0.15, 1.0. Let's put the emitter up to 2.0. We now have RGB 0.3, 0.3, 2.0. That clips to 0.3, 0.3, 1.0. See what happened? We raised all the channels, but only R and G had room to go up, so they increase relative to blue, leaving you with a desaturated blue. This doesn't happen with 100% saturation, because R and G are 0 in that case and don't get scaled up when you boost the power.
Btw, on the subject of the glare node, it doesn't clip linearly. I've never looked into what it does exactly, but it does some sort of scaling or clamping to avoid changing saturation or outputting superwhite values. (usually that's done by scaling down all the 3 channels by some identical value that will leave you with brightest channel=1.0)

Nice explanation! Confirms my thoughts.

I forgot that desaturating a color means you are bringing the other values up. Thank you.


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Use alpha of one texture node to mask another texture node
I have two texture nodes for my object. I'm using the "normal" node to create a bump map by connecting the "color" output of texture1 to the "normal" input of the "normal" node and taking the output to the "displacement" in "material output".
Now I need to apply the displacement only to those areas that are transparent in texture2. How can I use the alpha channel of texture2 to mask out texture1 before it goes to the input of the normal node?

I think I got it:
I used a mix RGB node and put my texture1 into the upper slot and a transparent color into the lower slot. Then I put the alpha of texture2 into the "fac" of the mix node.

@SixthOfFour There is time constraint before you can accept your own answer, I think it is two days.


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Can't make circle of objects using array modifier
Not sure what I'm doing wrong here.  As you can see in the .blend file, my cylinders are super wonky and distorted.  Trying to get them all the same size and in a tight circle with 5 cylinders.
http://www.pasteall.org/blend/39103
Thanks

related: http://blender.stackexchange.com/questions/31961/how-to-distribute-objects-in-a-circular-pattern-on-a-surface-radial-array-pola

Rather than using the empty as an offset on the array modifier, add a bezier circle the size of the circle you want and a curve modifier to the cylinder.  Select fit to curve and tweak the x offset until they fit.

Awesome that totally worked!  Thanks so much batFINGER


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How to make ribbon cable?
I've been trying to make a twisted ribbon cable using curves, the array modifier and the simple deform modifier, and I think I've come close but I just can't get the effect in the reference image.
This is the ribbon so far:

Here are my modifier settings:

Here's the reference photo:

As you can see, the cable in my .blend is not convincing and too uniform in the twist without that nice frazzled look of the reference image.
How can I achieve this?
Thanks

Update: A simpler improved file has been added with a screw modifier and with the other modifiers is completely flexible and editable. I did not add the noise though that is easy enough to do.

The original answer: Complex meshes and curves can get messy very quickly and I have tried to make a simple setup here. It uses a crude mesh created from screwing some circles around a vertical line/mesh...

...and adding an array modifier.

A subsurf is added for smoothness, but I also added a noise texture to displace the mesh a bit.

A new curve was created and added via the modifiers to original mesh.

This gives the freedom to move the mesh to the desired shape. The points of the curve can be used to manipulate the general volume with ALTS

The last part I cheated with another mesh as I think the transition can be obscured. It is duplicated to suggest more bulk and can of-course be messed with to suggest unique cables.

It's neither pretty or refined but hopefully gives you some ideas.
Updated file:

Orignal file:

Absolutely incredible.  Thanks so much for finding a solution to something that perplexed me for days!  But I have to ask; how did you get the circles to bend so nicely with the screw modifier?  I've come up with something but it has an angle of 2498 and 512 steps...I think I might be doing something wrong here :)

The screw tool (I don't think it can be called a modifier as it can only be used once) had 9 steps and 360 degrees. The Array modifier gives it the length and makes it easier for the curve modifier to deform later.

Ohhh OK I see.  I don't have much experience with the screw tool but I do have some with the screw modifiier.  Obviously different purposes.  Thanks again!

To be honest forgot about the Screw modifier - probably easier! After 360 degrees use 'Iterations' to increase the length - that way you don't need the Array. The Curve modifier also seems to work fine that way. The only problem I had is that I needed to Apply the Screw modifier to create different materials. Still always more solutions, than just one  ...

Updated the answer and added a new file. Screw modifier was a good call -  managed to keep it editable. By filling the faces in edit mode, different materials can be used without needing to apply the modifiers.

Yes I found you had to apply the modifier too which sucks but like you said, always more solutions!  Thanks for adding that to the answer.  That will help others.


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Muzzle flash on a gun
Is there a way to make muzzle flash come out of a gun using the smoke simulator with fire and smoke?  I've seen a lot of tutorials that use an object coming out of the gun that lights up, but it doesn't seem to look as realistic as real fire.
Thanks

This tut may help: https://www.youtube.com/watch?v=yKc8WNNV4Bw

Yeah that's the one I was watching.  It looks great, but when I watch actual videos of muzzle flash, it looks more like a flash of fire but still evolving or growing like the way fire would from an emitter.  Not sure if that's being too picky :p

Usually you wouldn't want to create a muzzle flash using a smoke simualtion. The flash is only visible for one frame.
I'd recommend you to parent a plane to your gun and create a Material for the flash with animated transparency.
Plug an image texture of the flash into an emission shader, so the flash illuminates the scene accordingly.

Wow nice!  This is a very interesting method.  I wonder if a video texture would be overkill?

I used a video texture from the commercial action essentials collection. The big advantage would be, that the muzzleflashes are unique and don't look the same the whole time. Also you don't need to keyframe the transparency for each gunshot.

That's amazing!  Such a great solution.  I will check out that collection.  Thanks again


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Problem creating energy material in cycles
I'm trying to make an effect of pulsing electricity/energy in cycles but the tutorial I've been following was in blender render and used transparency options that aren't in the materials tab in cycles.  How can I make the material so that it has a harsh ripple-like outline?  Right now it looks more like a ghostly jelly :p
This is what I have so far:

But with the cube, I want to have this effect:

Could you post a link to the tutorial you mentioned?

https://www.youtube.com/watch?v=bnrsoSagIU8


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Budget gaming PC as render farm?
Admittedly, I am not very knowledgeable of hardware, but I am trying to put together a cheap render farm using the following with my Lenovo Y50 gaming laptop:
GPU: 2X Nvidia GeForce GTX 1050 Ti
CPU: Intel Pentium G4560
Motherboard: ASRock 250M Pro 4
Memory: 16GB DDR4 RAM
SSD: Crucial MX300 275GB
Power supply: EVGA 450W 80+ Bronze PSU
Case: Fractal Design Core 1100
Link: http://www.pcgamer.com/pc-build-guide-budget-gaming-pc/
Is this a workable method?  Most articles I find online from CG artists are very expensive home made setups with render nodes, routing and server cases, etc.
Thanks

I wouldn't call it a render farm as you only have one other machine, but having a system dedicated to rendering (or other computation) is extremely useful. However, consider a single better GPU rather than two 1050's. Your processor is also not to fast. What is your budget?

Well I guess I was hoping to keep adding GPUs over time to make it almost like a render farm.  I chose 2 GPUS because I read it would be faster since blender can just assign rendering to them as if they were just slaves.  But to be honest, I'm really not knowledgable about these things so I am open to all suggestions regarding GPU.  I was hoping to keep it under $1000.

How is this off-topic?  https://blender.stackexchange.com/questions/5228/how-will-two-gpus-improve-cycles-performance

Because it is opinion based and related to specific hardware.

The question I was asking was more generally related to building a render farm with GPUs instead of render nodes.  I happened to mention the hardware I was looking at but I was not specifically asking for an opinion based on that particular hardware.  If you look at the link I posted to a similar question it was upvoted 14 times and not flagged.  These questions are useful for Blender users trying to build render farms.

Your configuration seems OK so far, but your CPU is rather weak. When rendering on GPU, some tasks are also done by CPU, the BVH for example (BVH = building the scene volume hierarchy).
Further reading: https://wiki.blender.org/index.php/Dev:Source/Render/Cycles/BVH
I'd recommend an i5 or something similar with 4+ cores. Don't try to save money on your computers brain. Also important: don't put in 16 gB of RAM as one module, it is more efficient to put in 2 x 8 gB modules to the two fastest RAM lanes on the mainboard (usually those are color-coded). When you want to put in more GPUs in the future, consider choosing a bigger PSU. 450 watt seem OK for two 1050ti, but if you double that in the future, you might hit the maximum wattage and your cards will slow down under full stress (the clock speed will be reduced to cope with the low power = slower rendering). This will also happen, when your system isn't cooled well. With two or more graphics cards, you need to pay close attention to cooling. Make sure your case is bigger than normal cases and has a lot of fans (as many as your PSU/mainboard can supply). I can't stress this point enough, I almost melted my pc last month. I'd also recommend that you put in an additional harddrive as a framestore, 275 gB is sufficient for your OS and some few programs, but when you choose to render a lot, you will need more space for your projects and renders. This "framestore" doesn't need to be an SSD. As for the SSD, you might also consider a M.2 module. This is an SSD module, that is directly put onto your mainboard. But make sure there are enough PCIe slots available, to hold an M.2 SSD and your graphic cards.
A little disclaimer: I'm not an expert, so any comments and corrections by the community are appreciated. Those are just some empirical points from my own hardware fails :-)
happy rendering!

Wow that's awesome info.  Looks like I have some more homework to do.  I should have mentioned the RAM would have been 2X8GB yes.  I guess it would be better then to upgrade all those parts I listed originally to have more capacity.


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How to scatter several rocks along a path?
I've been following Blender Guru's tutorial (https://www.youtube.com/watch?v=EesfCLQD8jY) on how to create a martian landscape, but I want the rocks to scatter on just one part of the surface using a particle system.  Is there a way to do this?
This is the area I'm talking about:

These are the particle settings (for one set of rocks)

See https://blender.stackexchange.com/questions/6250/how-to-control-hair-particle-position

Short answer: You want to create a vertex group and put that in for particle density.
Long Answer:
If you assign the particle emission to to the land you'll get something like this:
Obviously we don't want the icospheres all over the plane, just a select portion. We can do this we two methods, weight pain or creating a vertex group. Weight pain will give you more control, but I'll show how to assign a vertex group because it's a little bit quicker.
So tab into edit mode. Hit "c" and paint the vertices you wish to be affected.
Now invert the selection with Ctrl "i" and go to vertex groups on the right and assign a group.
Now go back to the particle system, scroll down to vertex groups and select the group. I would recommend naming the group.

Nice!  That worked very well!  I also tried the weight paint mode which like you said gave more flexibility


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Can’t find light in scene/why is it so bright?
Ok I have a scene that used to be a darker/less yellow world lighting before I started adding some lights/emissive planes.
I wanted to go back to the lighting I had before, so I changed the world lighting back and deleted the new planes. BUT the lighting is still like this:

I’ve looked for hidden light planes, hidden suns, and checked world lighting but it’s still yellow tinted.
What could be the reason? How can I get back to the lighting from a previous scene? I’m in cycles

Ah.. Note to everyone - apparently suns anywhere light the ENTIRE scene, no matter how far away

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How to make glass material LESS transparent/maintain its color?
Ok, Ive tried everything but here is what I have for a glass material (the teardrop) right now:

With this setup:https://blenderartists.org/t/colored-glass-in-cycles/631184
Issue is the glass is really dark right now, even with all colors set to white. I need a LIGHT colored glass despite the darker background, so still transparent but not as "inky"
How can I get this?

Increase the roughness??


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Export FBX with shape keys and animations takes FOREVER?
Ok, I am following https://www.youtube.com/watch?v=1Zqy5GhUV-Q just trying to export my skapekeys/animations in FBX from Blender (going to Unity).
Granted my mesh has a lot of parts and I had total 6 animations, but it has been loading for the past 2 min now. Did I do something wrong? I'm on a Mac and blender 2.79, cycles.
How can I reduce this export time? Im not even sure it's going through at this point.

Try 'Selected Objects only' - on my machine, Blender hangs for tens of minutes if this isn't selected as it tries to export every object's animation for every object recursively.


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Very weird - Why is only ONE BONE flipped weird (Blender to Unity)?
Ok I have tried everything here. I have a model that Ive exported to Unity as FBX, using the NLA editor all following a tutorial. Everything is great EXCEPT one bone (or combination - its the left leg) are flipped upside down.
So the animations all play, but that bone is just flipped -
Here is Blender, where Ive tested with removing ALL keyframes from that leg, still no luck:

And Unity:

What is wrong here?


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Shapekeys - how to smooth out mesh wrinkles?
Ok, Im a noob with shape keys and am having some trouble with "wrinkles" that show up on the mesh (really only when rendered w/ lighting) that are painstaking/impossible to try to get rid of just going into edit mode with the shape key on.
Basically, this is the winkled shapely in edit mode:

Wrinkles when rendered:

These were caused because I used an armature to position the mouth initially, and at first this mouth was wide open.Joining the faces in edit mode makes this even worse.. how can I fix this?

I can't seem to identify the wrinkles. Can you mark them on you image? I'd also advise you to read a topology guide.

They're pretty clear - See how his face has all the lines going away from the mouth? Those shouldn't be there.


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Boolean half the time doesn't work but does union?
Im not sure if Im doing something wrong here or what is happening but about 50% of the time whenever I do a normal boolean difference modifier, if I have at all modified the big object previously, I get this instead of a nice clean cut -

Where that bottom cube sticking out was supposed to be cut away. I have no idea what to do about it and oddly a union cuts a hole, but doesn't make the insides have "walls" so to speak. Ive tried recalc normals and everything here How to cut holes in an object using another object?
But nothing is working. What is wrong? its doing an additive boolean.

Add your blendfile to the post if you can.

A Boolean Modifier usually fails for one of two reasons:

Your face normals are pointing in different directions. To the modifier it seems like the mesh doesn't have a clear distinction between inside and outside. Happens often through extrusion. Select all verts and hit CTRLN to recalculate them.
Your mesh isn't watertight. That happens when any edge of your mesh has more (or less) than 2 faces attached to it. Deselect all verts and hit CTRLALTSHIFTM. That'll select most troubling parts. It can be useful  to do this twice, first in Vertex Select Mode, then in Edge Select Mode because the clues from what gets selected are different. If that's the case, recalculating normals won't work either. I usually go paranoid and avoid holes (only one face attached to any edge) as well.


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How to get shadows on the ground plane? (Noob)
I'm using Blender Internal. I have a ground plane set as receiving shadows, I have two light emitting planes, both have cast shadows on. I am using indirect lighting to utilize the effect of the light emitting planes. But I get no shadows cast on the ground plane, by the main object, a robot. How to get these shadows? Sorry for the noob question, I just suspect I'm missing some simple tick here or there, that will switch it on. :-)

In BI, the shadows may be achieved only by Spot lamps. in case of not turning on Raytracing option in Shading scroll (which is rather resources consuming)

Helpful. I have done some testing, and I figured I can use Area Light instead of Light Emission, but it gives a pretty hard raytraced shadow. An option would be to do a little bit Environment Light, say 0.1 this gives a nice soft shadow. And it seems Cycles would be a better option, only I already have all materials in BI. Will do some more testing later on today. Cheers.


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What shortcut to open Node Wrangler menu in 2.8?
I need the shortcut that will open the Node Wrangler menu in 2.8. I found this thread: Shortcut list txt for node wrangler from 2017. It says Ctrl+Shift+Alt+wm.call_menu. But what is wm.call_menu?? Anyway, I need a shortcut valid for Blender 2.8.

Shortcut for the Node Wrangler's Quick access menu in 2.8 is Shift+W.
Shortcut for Node Wrangler's Quick access menu in 2.79 is Ctrl+Spacebar.
You can also press T to open Properties shelf on the right in 2.8 or N to open Toolshelf on the left in 2.79 and prior and open Node Wrangler addon's tab; there you will find all the tools it provides with shortcuts shown if you hover over them as well as the Quick Access shortcut  written in the top.

I don't have any idea what Ctrl+Shift+Alt+wm.call_menu actually is; wm.call_menu is a command entered into RNA field in the user prefs shortcut dialog and has nothing to do with a shortcut itself, it's a way to tell Blender menu with some choices should appear. The source for the choices is then pointed out in the Name field.


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Weight Painting - Can't smooth this deformation
I have a rigged and weight-painted letter A. I'm content with all the weights except for the letter's left shoulder (Shoulder.L) bone. See image. The deformation is crooked, not smooth. I tried the Smooth, Levels, Normalize, Weight gradient, Blur etc. tools and I can't get it right. I tried reapplying automatic weights also with no success. Is the problem with weight painting or is it the underlying geometry (however the geometry here is very simple).
How to properly smooth this "left shoulder"?
Note that the other deformations on this letter are smooth, when I rotate the bones.
(I'm using Blender 2.79b)
I'm attaching a stripped down .blend file.

Oh, lame me! I understand now. I had to smooth the other bones' influence. The problem lay not with the Shoulder.L bone, but with the Neck bone and the Shoulder.R bone. They are influencing each other.
I would only like to add, that switching between bones and smoothing out the imperfections with the Blur tool does wonders.


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How to position the center of the Glare Node effect (in ghost mode) off center?
It seems the Glare node in Ghost mode is always centered in the frame.
I have 2 render layers:
1 for the Background and the Asteroid (with Object ID).
2 for a Sun object (A light emitting Sphere with Object ID).
I combine the Background, the Sun with Glare and the Asteroid on top.
When I Translate the Sun Object in the compositor, it affects the Glare, it changes intensity and shape, but it is always centered in the frame, even if the Sun travels from right to left edge of the frame. So it doesn't follow the Sun. It's just in the center.
How to position/control the Glare effect, so that its center follows the Sun traveling from right to left? (Note: I can't just put a Translate Node after the Glare, because the Glare will get clipped at frame edges.)

This is how lens flare actually works, its an internal reflection of the lens and describes the aperture that the path of light enters. All light passing through a lens goes through the centre at some point. So moving the flare centre around doesn't make physical sense.


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Weight Painting - Stiff vs Flexible Deformation
I have a rigged and weighted letter A. I particularly need to understand why, despite a nice gradient in the weight painting, a part of the deformation is nice and flexible (marked in green on the screenshot). And part is stiff like it's 100% weighted, though it looks like a gradient in the weight painting (marked red in the screenshot).
What I would like is that when I pose the bone, the deformation follows the weight-painting gradients on both sides. So it's flexible and smooth.
I would like to understand how to control this, so I'm more in control of the deformations.
I'm attaching a stripped down version of the .blend file.

What you're missing is another bone for the last horizontal part of the mesh, which will act as a "balance". In Blender Weights are always normalized, to distribute the movements between deforming bones, but if a vertex is weighted to one bone only, the normalization is calculated between a weight and zero: so a weight of 0.0001 and a weight of full 1.0 are treated the same way (both values are infinitely larger than zero).
The vertices in your "green zone" are affected by two bones, which blend their action, while the vertices in the "red zone" are affected by one bone only, leading to a "rigid" behaviour.


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Setting specific FPS for video
I have a video that was recorded using my laptops webcam.
According to the mplayer tool, my FPS for this video is set to 29.75 FPS (using the mplayer -identify -frames 0 myfile.webm command).
In blender's video sequence editor, under Dimensions, FPS, I choose custom, and then type in 29.75 for my video, but when I press enter, it rounds up to 30FPS. My video and audio tracks don't line up.
Why doesn't it let me set the specific FPS? How can I best rectify this situation?
Thanks.

What happens if you use the 29.97 preset? Is it still off?

Yes, at 29.97FPS I have 81002 audio frames and 80407 video frames, at 30FPS I have 81083 audio frames and 80407 video frames.

After playing around with it a bit, I think it might just not be possible at the moment. Is there any chance that you could use an external video editor/video converter to bring the frame rate to 29.97 or 30? Also, I think this might be something worth talking to a dev about. It doesn't seem to good to be to limit frame rates. I just checked, and you can't add anything about 120 also, which could be pretty limiting.

I happened to test with some other video @120 FPS, and that does work fine. FYI.

Have you tried to play with the framerate base? fps 60 with base 2.017 seems to set 29.75 fps, but I don't know if this works for you... this BA thread has similar issue, it seems http://blenderartists.org/forum/showthread.php?138831-Frames-per-second-base

hmm, maybe some time remapping is also needed... ?

As you have noticed the FPS can only be set to integer values. To get a fractional frame rate you need to also set the framerate base which you can find right under the FPS.
The easy way to get the right base value is to enter a calculation which is the set fps divided by the target rate. eg 30 / 29.75, when you then press enter it will show the value of 1.008 and the frame rate will show as Custom (29.75 fps)


text:
Baking Ambient maps, black noise?
I have been struggling a lot lately with AO map baking, and just ran into a new problem! I'm currently trying to bake out occlusion maps for a few rocks, been doing it to several different ones with little problem, but just finished rendering a few out from a few very highpoly rocks and get weird black "pixelspots" Not sure what I'm doing wrong, i am on highest sampling possible, and i tried raising the "bias" which helped, but as it decreases the amount of shadow aswell its not quite the solution i wanna go with!
Has anyone bumped into this, and got a solution for it?

No, I have not had this issue before

Could you show a bit of your scene&setup? Or upload a portion of the file? Maybe it could be helpful in guessing where the problem cames from. Does it happens even if you append the objects in another file? Does it happens to "new objects" too?

Ye, haha that was actually me! but this isn't the same problem as far as I can tell, but ill upload a portion of the file! And I'm doing the multires method when trying to bake the AOMAP! https://drive.google.com/file/d/0By4AwCMVSPt4MEZkMDNzXzBHdG8/view?usp=sharing

Here is the solution for this baking senario:
Note The result are correct, you will need deep crevices to create really
dark shadows or details. If you need more shadows on your ambient map consider using a 2D image editor like photoshop or Gimp to up the levels.

Change your baking bias from 0.001 to 0.01

Oh okay, well i did do that before, and it did solve it but it removed a lot of the shadows as well! But i guess ill just use PS to increase the amount of shadows as you said!


text:
Why do measurements change when switching from Global to Local in edit mode?
Why does the edge length information shown after ticking Edge Info -> Edge Length under Mesh Display change after choosing Global or Local?

2.76 is quite old, upgrade to a newer version. Edge length in Global coordinates depends on a lot of things like object scale, modifiers, deformations applied among others.

Global is based on the 'World' coordinates (0,0) where 'Local' is relative to its self, which could be anywhere in 'World' space. [hope i got that right].


text:
Part of the Mesh goes missing
I was modifying some of the weight paint for a hand model that I was getting ready for some simple hand animation gestures and when I started doing some of the animations I saw that there was a piece of my mesh missing. How do I fix this? Do I have to start all over? pictures and file below.

File here:
https://drive.google.com/file/d/0B5Q_BpDCNgg6cG9zM2UxeFlwcDQ/view?usp=sharing

Still need some help I don't know how to solve this.

I checked the weights and they're quite decent. It is really strange it deforms in the ugly way. I had similar problem with strange mesh deformations some time ago and had to build (retopologize) my model again from scratch to make everything work properly. Maybe it's some kind of a bug??

Thanks, Did not know what retopologize ment until I looked it up. I'll give it a try.

Imho weights are not that OK. there are many isolated vertices here and there that have weights and (always imho) they should have zero.

I just post this to show some error in the weights. I downloaded your file and just reset the pose of all bones (ALT + R)
then selected bone.001:

this bone is not supposed to influence the hilighted area...
there are also many minor errors, maybe just 1 vertex here and there, quite subtle on various bones, but those also "move" your geometry in unexpected ways...


text:
Can I display the image from a camera on a plane in the same scene?
OK - I have a small spacecraft with limited vision inside. The spacecraft is racing against others. I want a holopanel to either side of the pilot, displaying what is to either side of the craft. It this possible in the scene? I want to try and avoid faking it in post if I can.
I will be rendering in Cycles as a short video.

I don't think  Blender is capable of render two cameras in the same process.
But you can make the light from the sides reaching the camera in the old way: make a hole in the ship and bend the rays by 90° (with a mirror).

In the picture above you can see Suzanne in a whaleish vehicle with some other smaller spaceships (red, yellow and green) on both sides.

Anyway I think it would be easier to put two cameras and composite the holograms in post. You'll surely have much more control on their final appereance.


text:
apply cloth with different body
there is a tight cloth which I want to apply to a body
but the cloth shape is different since the cloth comes from the different body.
I tried to fit it as much as possible and used sculpt painting,
but it ruins the texture alot.
is there any other way to fit cloth to the body?
sorry I'm still new to blender.

Have you tried simulating the cloth object as "cloth" in the Physics panel? It'll make the object behave like real cloth. Set the cloth as "cloth" and the body as "collision", and press the "Play" button in the timeframe, and it should go well.

I am not talking about the animation. and even if I tried cloth and collision it doesn't work because the cloth doesn't fit with the body at all, and it actually causes the cloth just break apart and fall down. maybe tweak cloth mesh to fit the body shape can be the solution, but its gonna be a hard work since there's alot to do.

JKIM, could you please upload a .blend file? I'll see what I can do.


text:
I would like to copy object shape and apply it to another object
Let's say I have 2 bodies with different shape.
Body A is more fat while Body B is thinner.
I want to change body A to have a body B shape,
but keep the body A vertex group, weights and bones.
is this possible?

Check out this: http://blender.stackexchange.com/questions/34758/how-about-blendshapes-not-shape-keys May be helpful.

its not exactly what I wanted since 2 bodies has different vertices and edges. but thanks anyway this would be helpful.

Different vertices and edges? Do you mean 2 bodies has a different number of vertices?


text:
How to check if a texture is already in the blend file before importing it while appending an object?
Matthew here with yet another question :p
Anyway...I found an answer by @zeffi on how to append an object using python, that's all goods, but the trouble is, every time I append that object, it imports the textures in, every time, which means that after about 5 appends, I have 5 copies of every single texture, which slows blender down dramatically, and also increases my file size from 150mb to something like 1gb...sooo, here is what I was thinking, in steps:
Append the object, then check if all the textures imported in with the last 'append' are there already, and if they are, then delete them, otherwise leave them there. It sounds pretty simple but I just don't know how to go about it. Here is the part of code that should concern so far:
class AddMacBook(bpy.types.Operator):
    bl_label = "Add MacBook"
    bl_idname = "macbook_controller.add_macbook"

    def execute(self, context):
        item = context.scene.ignit_panel.add()

        macbook_path = '/Users/MacBook/Documents/Blender/Blends/MacBook/Macbook.blend'

        macbook = 'Macbook'
        screen = 'Screen'
        Directory = macbook_path + "/Object/"
        m_path = Directory + macbook
        s_path = Directory + screen

        wm = bpy.ops.wm
        wm.append(filepath=m_path, filename=macbook, directory=Directory)
        wm.append(filepath=s_path, filename=screen, directory=Directory)

This should obviously be an builtin append feature. I guess the way that 3d studio max does it is best. It checks for materials that has the same name, If the names are the same, a dialogue box will pop up asking you if you would like to keep the material and rename it,  or use the one already available in the blend file.

Do you know how I could achieve the same effect?

related: http://blender.stackexchange.com/questions/44542/how-to-check-if-a-texture-is-already-in-the-blend-file-before-importing-it-while and related http://blender.stackexchange.com/questions/17876/import-object-without-bpy-ops-wm-link-append

lol, the first link is this exact question! And the second one, does it not import textures?


text:
How to rotate a 'non-active' object with python?
I have a laptop model and I want to be able to control the rotation of the screen through python. I have a basic menu with a slider. I had an armature and a bone and I got that working but it only worked when it was selected and in pose mode, however I want to be able to control it regardless of whether its selected or not. So I removed the bone and separated the screen from the body. But now its the same thing, I can only get the screen to rotate when it's selected...
This is the line of code that rotates the screen:
bpy.context.object..rotation_euler[0] = (self.screen_rotation * 0) + ((1 - self.screen_rotation) * 1.58825)

How can I make so I can rotate the screen without it having to be selected?

You could lookup the object by its name:
o = bpy.data.objects["Cube"] # Cube represents the name of your object

and manipulate the rotation
o.rotation_euler[0] = (self.screen_rotation * 0) + ((1 - self.screen_rotation) * 1.58825)

authors: Χρήστος Φιλιππίδης


text:
How to make my prop search show the objects in my scene?
I have a simple object selector using a prop search. At the moment it runs but doesn't show any of the objects in my scene. This is what it looks like:

How can I get that to show all of my objects?
Here is my code, I've dug out only the parts that should concern it...hopefully
class IgnitProperties(bpy.types.PropertyGroup):

    screen_selector = StringProperty(
        name="",
        description = "Select the screen that goes with the unibody to rotate the screen properly!"
    )

    coll = CollectionProperty(
        type = bpy.types.PropertyGroup
    )

class IGLayoutDemoPanel(bpy.types.Panel):

    def draw(self, context):
        # Screen Selector
        layout.label(text = "Screen Selector:")
        layout.prop_search(scene.ignit_panel, "screen_selector", scene.ignit_panel, "coll", icon='OBJECT_DATA')

When using property search, you need to specify the collection of objects you want to search through in the 3rd and 4th parameters (in our case the list of objects in the active scene):
layout.prop_search(
    scene.ignit_panel,  # Object with your custom property
    "screen_selector",  # Your custom property
    context.scene,      # Object that contains the collection you want to search through
    "objects"           # The collection property
)

Anyway to ask not Camera nor Lamps and only pick from Geometry?
"objects" seems to inclusive.


text:
What is the C# Mathf.Lerp equivalent in Python?
I have a basic menu script with a slider. The idea is that the slider will control the rotation of a bone. That bone will then rotate the object. I worked out the exact euler angles to rotate it by, and now I'm a little bit stuck. I've used C# for quite some time and C# has this thing called Mathf.Lerp, and I wondered if there is a python equivalent? If so, what is it?
Here is what I'm aiming for:
elif origin == 'screen_rotation':
    bones = bpy.context.object.pose.bones

    Mathf.Lerp(bones["Screen"].rotation_euler[1] = 0, bones["Screen"].rotation_euler[1] = 1.58825, screen_rotation)

Related: http://blender.stackexchange.com/q/19595/599

Lerp typically means linear interpolation.
Assume A, B, C are floating point values.
Assume C is in the range [0.0, 1.0]
lerp(A, B, C) might be implemented as
value = (C * A) + ((1-C) * B) // convex combination
When C equals 0 value equals B.
When C equals 1 value equals A.
When C equals .5 value equals the average of A and B.
Of course you can switch the factors (C) and (1-C) depending on your desired implementation.  You can also switch A and B depending on your desired implementation.

Ok, so is this right? bones["Screen"].rotation_euler[1] = (self.screen_rotation * 0) + ((1 - self.screen_rotation) * 1.58825)

Ok, it works, but only when the bone is selected and in pose mode...

The Blender python API provides the equivalent functions for linear interpolation (Lerp):

Vectors.lerp
Matrix.lerp

The quaternion alternative of euler angles requires spherical lerp

Quaternion.slerp


text:
How to fix 'AttributeError: 'Mesh' object has no attribute 'active_index''
I'm trying to use python to make a very basic tool to add a new uv map to the selected object and uv unwrap it with a lightmap pack, then select the default uv map as the active one, change into object mode and hide the object. So far it gets up to un wrapping the object but then it stops and gives me the following error:
bpy.ops.object.hide_view_set(unselected=False)
Traceback (most recent call last):
  File "/Applications/Unity 5/Projects/Cartoon Driving/BlenderAssets/Map 01/Map 01.blend/lightmap_creator.py", line 15, in execute
AttributeError: 'Mesh' object has no attribute 'active_index'

location: <unknown location>:-1

Here's my code:
import bpy
from bpy.types import Menu

class Fence_Operation(bpy.types.Operator):
    bl_label = "Lightmap"
    bl_idname = "lightmap.lightmap_panel"

    def execute(self, context):
        bpy.ops.mesh.uv_texture_add()
        bpy.ops.object.editmode_toggle()
        bpy.context.object.data.uv_textures["UVMap.001"].name = "Lightmap"
        bpy.ops.mesh.select_all(action='SELECT')
        bpy.ops.uv.lightmap_pack()
        bpy.ops.mesh.select_all(action='DESELECT')
        bpy.context.object.data.active_index = 1
        bpy.ops.object.hide_view_set(unselected=False)

class IGLayoutDemoPanel(bpy.types.Panel):
    bl_label = "Lightmap"
    bl_idname = "lightmap.creator"
    bl_space_type = 'PROPERTIES'
    bl_region_type = 'WINDOW'
    bl_context = "data"

    def draw(self, context):
        layout = self.layout
        row = layout.row(align = True)
        scene = context.scene

        row.operator("lightmap.lightmap_panel", text = "Lightmap")

I don't quite understand how to fix this though, I just copied the code that came up in the Info panel when I actually did it, and dumped that into my python code. Why doesn't that work? Does anyone know how to fix it?

Replace
bpy.context.object.data.active_index = 1

with
context.object.data.uv_textures.active_index = 1

The mesh is not a collection and has no active_index, hence the error.
Also consider using the last in the collection rather than by name 'UVMap.001'
context.object.data.uv_textures[-1].name = "Lightmap"

To get on my soapbox replace bpy.context with context as context is passed via the parameters, eg def execute(self, context).

authors: Александр Гаврилюк


text:
Merging multiple uv maps with textures into one
I have 11 mesh items with 11 individual UV maps that have already been connected to 11 separate image textures.

When I combine the meshes into one mesh, I have many overlapping faces in the resulting UV map, and re-sizing the islands distorts the textures.

Is there a way to avoid manually re-arranging the textures to a new, single UV, such as with texture baking?
Note that this is in the Cycles render engine.

You can try to rename UV maps before joining objects. As they are named differently, Blender won't join them. But there's a limitation to UV maps quantity. Probably it's possible to combine e.g. 7 at once, bake texture, delete these 7 and so on. Not sure if it's convenient though.

Unfortunately I think my skill in Blender is too little to wrap my head around texture baking, so I'm just going to redo the single texture. Thank you very much for trying, and maybe I can attempt this when I know a bit more what I'm doing :)

Have a look at the texture atlas addon


text:
Any help with that material?
I'm trying to make my material look like this

I played with nodes but couldn't come up with anything resembling the yellow material in picture.

Related - http://blender.stackexchange.com/questions/40565/mixing-colours-to-create-a-gold-shader ?

Material appearance is the result the interaction of multiple factor such as the light, the environment, how the object is modeled and, finally, the shader itself. Could you show what you have done so far to get an idea of where exacty you are stuck?


text:
how to separate one object into different parts?
I do not know exactly what I did, but I am a beginner/noob with Blender. When I select one shape all of the shapes have an orange outline. I don't really know but they are all somehow on the same line/tab. I wanna put them each back to their own tab. Look at the picture to see what I mean. 3 of the shapes have an orange outline when I click "cube" even though it should only be one cube. I wanna make each one its own line again. See how the cones are not selected, each cone has its own separate line/tab. I feel like it is really simple to fix, but it is probably a rare problem so I do not know how to fix it since I am new. Any help would greatly be appreciated.

Try following these steps:

Select the object (In this case it is 'Cube')
Go into Edit Mode (Press Tab)
Press A (Deselect/Select) until everything of that object is selected
Press P -> By loose parts

All of the objects should each have a different 'outline'


text:
Rename folder/file in blender file browser?
Is it possible to rename a folder in the blender file browser? How about a file?

You can do this using Ctrl+LMB. Simply hold Ctrl and click on the file or folder you would like to rename.


text:
Mesh deform a curve with shape keys
How do I deform a curve or a mesh using the mesh deform modifiers and key frames. Basically, I'm trying to bind the curve to the mesh when the mesh at its Basis key. I then turn up the influence on another key(on the mesh). The curve does not deform.

A curve is defined by a number of points and the connection between each point is then calculated. Any deform modifier on a curve can only move the points that define the curve, it cannot distort the curve in-between two curve points.
To get the benefits of a mesh deform modifier on a curve you need to be sure that the areas of the mesh that are deformed by shapekeys are surrounding a point in the curve.

I don't know why I didn't think of that. It's odd that the modifier is even available for the curve, since it doesn't work properly.


text:
Ocean modifier source code
Is source code for the ocean modifier accessible? I looked through my Blender installation, but I can't find it.
I'm trying to create a game (not in Blender because it's for iOS/Android) and would like to use real-time generated ocean waves rather than using prebaked .obj files, but have no idea how to make waves like that on my own.

You can't find the source within the Blender installation because it's compiled code (C/C++).
An probably older implementation: Blender_Ocean.c has pointers to the original paper by Jerry Tessendorf Simulating Ocean Water.
You find the current source file in GIT version control

From Blender's wiki:

The core simulator was developed by Drew Whitehouse, for the Houdini
  Ocean Toolkit. This was ported to C by Hamed Zaghaghi and integrated
  in a patch for the Blender 2.4 series, sponsored by ProMotion
  Studios/Red Cartel during production of the short film Lighthouse.
In this work, Matt Ebb re-integrated the core simulator for Blender
  2.5, and added additional functionality, fixes, and optimisations, sponsored by the 'Save the Ocean Sim' project.

So perhaps the Houdini Ocean Toolkit is a good place to start for a non-Blender implementation.


text:
Render transparent object distortions but not the transparent object
I'm trying to render some artifical object behind glass.
This object has its material properties in such a way that it produces refraction (raytrace transparency with IOR > 1), reflections, and it casts a shadow.
The setup:

I use a real-life image as a background to render the scene, you can see the results before and after the process:

http://www.youtube.com/watch?v=30pFzvcwQnc
Please note that the model is not an accurate representation of the real object (I'm ok with that).
I want to get rid of the transparent model on the right image and keep only the distortions on the apples, the reflections of the apples on the object and the shadow cast upon the table (there is no real table in the model, it's just the image)
It should look like the original object (the glass on the left image) is casting the shadow and producing the refraction and the reflections.
As the model is an approximation of the real thing, it is ok not to have accurate distortions.

Are you using BI or cycles?

No, I´m quite new in blender

Gandalf is asking which renderer you are using. Blender Internal or cycles? Check the drop down in the header at the top.

Ups, it is Blender Internal

You can separate the reflections/refractions by enabling those passes in Properties > Renderlayers.


text:
My Blender File Won't Render!
I've got a  file and it fails to render, I'm not sure why.
When I hit the render button a grey pixelated screen comes up and it doesn't seem to process. I've tried playing around with the settings, but I get nothing. When I hit Open GL render then it looks like the render version of the image, but  it doesn't include the background color scheme!

As long as your question is that general, I doubt that anyone will want to guess the dozens of possible reasons why you don't produce an image. Please be more specific. Do you get a black screen? does Blender crash? Does anything happen when you press F12? Have you tried rendering from the menu instead of the keyboard shortcut?

And, maybe, add a link to your .blend for us to see what happen?

I'm not sure I'm understanding.. When you press OpenGL render it looks like the actual render, not an opengl render?

It is hard to understand what you are asking. Please edit the question with more specific details and attach screenshots and or a blend-file.

OpenGl Render doesn't render the World Color. It renders the theme color. Hit Numpad 0 to check where the camera points. Put a new object (shift a) right in front of the camera and testrender, then provide more detail. We'll work it out.

Maybe take a look at this: http://blender.stackexchange.com/a/5286/1259  Sounds like your problem. Short answer: Check for any stray video strips in the VSE.


text:
How can I obtain an even vertex density base mesh?
I modeled a simple wall with a window using a cube and loop cuts. I also set the crease of each edge to 1.0. I intend to sculpt it now to get a rougher look. The problem is that when I add a subdivision level with the multiresolution modifier,  I get a mesh with a highly varying vertex density.

Is there any way I can subdivide it to get a base mesh with an even vertex density?

You don't need to crease, You can just set the sub-surf to simple.

Why don'y you first subdivide the cube to whatever density you want and then cut out a window?

Add loop cuts to the larger parts of the wall ctrl R, so that the size in between the loops is about the same as the thickness of your wall. Then subdivide, if the base mesh has about the same size topology, then subdividing will yield same size topology.

You either need to have square faces before subdivision or use something such as the re-mesh modifier. I should note that the re mesh modifier will only work well on simple meshes such as the one you're working with. I would experiment with the Blocks mode as well as sharp, being aware the the Blocks mode will mess with the shape of your mesh.

Do you not like large images? You shrunk both the question's and my answer's images, why?

They can make stuff painful to read, as well as making the page very long. Also, for some people(with bad internet), they can make the page slow to load.

@David You can remove the M from the end of the file name, and they will go back to normal size if you want. eg. imgur/examplem to imgur/example.

I know this is old, but I'm going to necro this because I found a work-around.  Be sure never to rescale (in part or in whole) your objects.  Cut your objects to their general shape with boolean difference operations.  This will maintain the uniformity of the mesh when you use the remesh modifier.
Example:
Let's say you want a slab.
Ordinarily you would simply start with a cube and scale one dimension of the cube to the slab thickness.  This, however, results in scaled mesh points.  When you remesh this, it will remesh with squares on the unscaled sides and rectangles on the scaled sides.
Instead, start with a cube, but create a second, larger cube as well.  Use the larger cube to cut the first cube into a slab using a boolean difference operation. Doing this will allow the remesh modifier to generate a uniform, square mesh on all sides regardless of the mesh size you choose.
Alternatively, you can begin with a plane and extrude it to the slab thickness.  I've discovered that this kind of thing works too.
I don't know why Blender works this way, but it does.
Once again: My personal rule is to never scale an object until I am finished sculpting it.  Every time I've violated this rule, I've suffered for it.
Here are some other tips I've found useful:

When working with multiple objects, always remesh them to the same Octree Depth.  If you don't your boolean operations could go wonky on you.  Following this rule will also guarantee the most uniform mesh on your final object.
Always remesh your objects immediately before you use them in boolean operations.  Again  inconsistencies in the mesh due to boolean or sculpting operations can cause unpredictable results.
When remeshing, use the "Smooth" option if you have used brushes to sculpt your objects and you plan to use boolean operations on them later.

Unfortunately, once the quality of the mesh is compromised (e.g.: the object above) there's no way to "fix" it short of manually editing the mesh, in which case, you might as well just start over again.
Hope these help.


text:
Bake Fluid Simulation via CLI or Python?
I would like to run a fluid simulation on a headless Ubuntu machine I have lying around. I did manage to find a bug report on the issue but to no avail. Has anyone else had any success? Or perhaps a better solution to my problem?

Works fine for me.. Is it possible you could upload a file where it doesn't work?

You can't upload .blends directly to SE at this time, but pasteall is a good blender-specific option for temporary usage. For more permanent storage, there's blend-exchange

It works fine for me... It spits out a bunch of errors like you describe, but it still bakes

It's a bit more complicated than it could be because fluid simulating baking is only exposed as an operator. That means it expects an active object in the context, which is usually provided by the user interface that is not available in background mode.
It is possible to pass this object to the operator manually however. The following is an example script that bakes all fluid domain objects in all scenes:
import bpy

for scene in bpy.data.scenes:
    for object in scene.objects:
        for modifier in object.modifiers:
            if modifier.type == 'FLUID_SIMULATION':
                if modifier.settings.type == 'DOMAIN':
                    bpy.ops.fluid.bake({'scene': scene, 'active_object': object})
                    break

This works when executed from the command line with a command like this:
blender --background file.blend --python script.py

Just out of curiosity, are you Brecht van Lommel, the Cycle Developer?

Yes, that's me.

This answer just made my day - only the co-producer of Blender could figure out how to bake fluids.

Does this mean we can in fact bake multiple domains with one command? The UI complains when there are multiple domain objects

In Blender 4.0.2, I hunted around for a while. The bake function, from Brecht's answer above, complained about 1-2 args, and I didn't know how to solve that. Here's what works for me:
Create a script bake_fluids.py, like:
import bpy

for scene in bpy.data.scenes:
    for object in scene.objects:
        for modifier in object.modifiers:
            if modifier.type == 'FLUID':
                if modifier.fluid_type == 'DOMAIN':
                    print('baking...')
                    object.select_set(True)
                    bpy.context.view_layer.objects.active = object
                    bpy.ops.fluid.bake_all()
bpy.ops.wm.save_mainfile()

Then run it like:
/Applications/Blender.app/Contents/MacOS/Blender \
    --background \
    ~/BlenderFiles/test_render1.blend \
    --python bake_fluids.py

Notes:

change the path to blend file to your own blend file
If you're not on Mac, use the Windows or Linux path to Blender executable, as appropriate, e.g. simply blender, on Ubuntu, perhaps)


text:
Problems with rotation and scale importing blender object to unity? Replicate unity cube?
I am having real problems and am very new to blender/unity. Right now I have a script that resizes and creates variable longer blocks from a basic cube in unity. I won't show the script as that might not be relevant but this is the result when the script is run to give you an idea -

The original prefab is the default unity cube but the script scales it, etc.
I am trying to replace this cube prefab with an altered cube (a cube with the top right and left edges cut off) to create variably-sized platforms such as this -

I am very new to 3D and so started by just created a simple modified cube in blender -

When I drag this cube into unity it shows up well however when I plug it into my script it elongates the cube in the wrong direction, etc. I know the rotation is off, so I tried to fix that first by rotating the object in blender (this did nothing) and then creating an empty Gameobject and rotating the object there as Unity says, but nothing is working.
In addition to rotation I think the scale of the blender cube is much bigger than unity cube. Furthermore I do not know how to add colliders or other components to my blender object if I just import it- seems I have to drag it into an empty first or the options are all grayed out. Mostly I think I just don't know how to properly import from blender to unity despite tutorials.
This is what happens when I run my script as opposed to original picture  -

Clearly a lot is going wrong here. I just want to replicate the default unity cube in blender and modify it so when I bring it back to unity I can use it in my script. How can I do this? What am I doing wrong?

Yes, Blenders scale is different, if you are using FBX (which i would recommend for Unity likes it), there is an export options called: Apply Transform (Experimental!). This works for me, otherwise, scale your final mesh down to compensate (Unity's scale is 100x smaller, so it makes the cube's scale 100x100x100, you can also adjust the mesh import scale in Unity, instead of compensating in Blender).
In Blender, if you make any changes to the rotation in object mode, you need to apply that rotation (CTRL - A) before it exports it. Also, the reason the rotation is wrong is due to Unity using the Y axis as its up axis, and for Blender this is Z. You can compensate by making the up axis of your mesh the Y axis in blender. See posts like this for more info: http://answers.unity3d.com/questions/174832/stopping-the-270-degree-fbx-default-rotation-on-im.html
If you are still experiencing issues something is going wrong in Unity, and you should post the issue in the Unity section, with your script included. And good luck and have fun learning!

I really need some help. I am not using fbx i am just saving my .blend file into unity. I think the scale isn't a problem anymore its just rotation. I've watched all the tutorials and again I've rotated my object to have y axis up in blender but nothing is working. What would you suggest?

Just to be clear, are the custom cubes scaling wrong or not scaling at all? For you say it scales it wrong, but from the picture it appears they arent scaling at all. The only problem i can think of off the top of my head is that maybe you are scaling in the wrong space (local / world). Or maybe Unity handles cubes weird when importing .blend, you could try making only the cubes .fbx (never imported .blend in Unity myself.)


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How to mirror cut or modification made to basic shape?
I am very very new to blender and have seen similar questions but just need an explanation - I have finally succeeded in cutting the edge off a cube using the boolean modifier here -

and I need to know how to make this EXACT same cut on the other side. I have gone over many tutorials and attempted to use the mirror modifier but the best I can come up with is duplicating the object, flipping it and trying to join it to the original. There must be a better way here.
How can I mirror any modifications I make to an object across 1 axis of the object?

Just wanted to add that for this particular mesh manipulation you can simply select the edge and press Crtl+B for Bevel, if you don't need the exact measures of the cutting object. Selecting the edge on the other half will result in what you want to achieve here.

I can't see any reason to not use Mirror modifier in this case, either before creating that beveled edge on the top or after.

Blender wont mirror operations made on a mesh but will mirror the mesh itself, in the state it is when the mirror is applied.
So, most of time, you may anticipate that your shape will be symetrical and define the mirror appropriatly.
By default, mirror is applied along the x-axis (1) and at the center point of your mesh (the yellow dot you can see in object mode marked 2 here).
In this example the mirror position corresponds to the plane defined by X=3, as the mirror is on X and is defined relatively to the object's center at the position (3, -1, 0).

This previous image shows a cube. But in fact, only a half cube is defined in this example :

This half cube is not a plain figure, but some kind of open box as a face is missing (see above) because the final mirrored cube does not need an inner face (at least this is the most common situation but this is not mandatory).
Once the mirror is placed and if you want to use the boolean modifier, some tricky things may happen (boolean modifier is not allways so simple) : or the intersecting object is not itself mirrored or it is :

If it is not, all is fine, and you obtain this kind of result when you apply the boolean modifier :

But if it is the two shape will be intricated, and that's probably not what you want :

So to avoid that, an easier way is to work on a half of the model (not mirrored) and add the mirror modifier once finished with the boolean.
In my opinion (but the following remark may be considered as subjective), using the boolean modifier is not the simpliest way to start using Blender, even if it seems "simple" at first sight (it may also have some other unwanted consequences).
So for a begining, I'd suggest to keep using the mirror modifier (if you need it) but go in edit mode to model your shape manually.

I've tried to follow your answer but I'm only able to mirror after selecting another object (i.e. camera or lamp) and this results in the mirrored object stuck on a different axis.. what am I doing wrong here?

@skyguy can you provide a screen capture of this ?

Good detail to your answer, but the premise to it is simply not true. See my answer for further clarification.

@pycoder, this question was bumped just now... and after a new read, I still wondering... what is false 'in the premise'?

@lemon If you do what I showed in my answer, the operations can be "mirrored". You said that "Blender wont mirror operations made on a mesh," but this is not true.

@pycoder, I meant operations like cutting, subdividing. I was not able to do it just using X mirror. Or am I missing something?

@lemon That's correct. Transformations work, but you can't change the vertex count in real-time like that. However, by clever use of the Symmetrize tool, you could keep up with it quite easily...you could even write an add-on that did it every time that the vertex count changes...

Blender does allow you to do this, but a mirror modifier is more often used:

Just enable the X Mirror option in 3D View > Tools > Options > Mesh Options > X Mirror. Note that this will only mirror along the x-axis (that should be your mirror axis anyway) and will only work if the mesh component (vertex, etc.) is at the exact same position as the one on the opposite side. To insure symmetry use the Mesh > Symmetrize tool.


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How to achieve this low poly lighting?
Ok, new to 3D lighting overall here and Ive gone through every Blender lighting tutorial for low poly like PigArt, etc but can't achieve this lighting/rendering - low poly so that the triangles are defined but more glossy:
https://dribbble.com/shots/3471048-Xbox-clubs-image
OR
These are different from just a basic sun light, the world set to white color and everything that is described in tutorials. Ive tried setting materials to glossy but still can't get this.
How can I do this? Any good tutorials?

Cycles or Blender Internal?

cycles renderer

I've looked at the other works from Alex Pushilin and here is my attempt to reproduce it.
Setup is very simple. One Sun Lamp with warm color and small Size and RGB Background (this one is with Spherical Gradient).
For materials I've used Principled Shader with Roughness - 1.0.
Most important thing here is to use Filimic Color management. I've used Look > High Contrast with a little correction from RGB Curves.
Also I've lower a bit Saturation in Compositing.
Every probably will need a little bit different settings.


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One single texture turns out black
I have a bit of a weird problem. Im working on a simple road, and sidewalk. Ive applied both the sidewalk texture and the road texture. But here is the problem, the sidewalk texture is showing up perfectly fine in "material-mode" and "realtime render mode", but the road texture only shows up when i render the objects. And here is the weirdest part of all, if i load any other texture to the material instead of the road texture it shows up fine, but as soon as i load back the road texture it turns black again.

Is it possible you could upload the .blend?

Yes of course! https://sprend.com/download.htm?C=5d34eca9a1014a2db098313f0ef0accd

For future uploads please use file service which doesn't delete files 2 hours after successful download. In case of Blender.SE you are welcome to use blend-exchange service.

Oh well, didn't even thought of that, but here is a new link, blend-exchange didn't seem to work for me. http://www96.zippyshare.com/v/fZDnyXTh/file.html

Could you please upload the file somewhere trustworthy, like dropbox? Or at least something that doesnt make my watchguard go all crazy... Anyway at first sight I would say that you can't see the road texture because it wasn't applied in the UV editor window to the mesh, while the other one was. To fix this, go to the UV editor while in edit mode on the black mesh, and select the texture you want to preview on it.

Well I'm sorry for that, but anyways, i tried fixing it like you said, but now i can't even enter "material mode". Blender just crashes when i try to. But i can enter "texture mode" which shows my different textures blend into one without any problem, so it seems to be some problem with the material itself! I might be completely wrong, but it feels like that is the problem.


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My Particle System just stopped working
I have a big problem, I just finished making a fairly demanding scene, And i did a render just a while ago, but then i tried importing a tree into the scene before final rendering, it ended up being a bit too much for my computer. So i deleted the tree and got back to rendering, but all of a sudden blender just crashes whenever i try to render.
And it seems like its a problem that has occurred with the particle system, because I can't even turn it off or deleting it without crashing blender, And also before this happened i could render at 60000 particles now it crashes even if i pull it down to 1.
Another thing is, I can disable it from rendering, and at least render without the particles, but it doesn't seem to be a performance issue, as i couldn't even render it at 1 particle.
Do anybody know what might be going on?
(Also just one more thing, I can't even move the object that has the particle system applied to it without crashing blender.)

Did you cache the particle simulation?

No, I didnt do anything, as far as i know anyways! All I really did was making a tree, and the tree was making the scene too slow, so i deleted it, and then when i decided to keep the rendering going without the tree, it just didn't work anymore! I even tried appending every object i used to a new blender file, but the particle system crashed the new blender file aswell!
But is there a way to see if i accidentally cached it?

It would have been something you would have had to actually do yourself. Maybe try uploading your .blend to Blend-Exchange

Yes I tried uploading it, but its too big for Blend-exchange, so i uploaded it on google drive, here is the link https://drive.google.com/file/d/0By4AwCMVSPt4aDFRZURZb3AxNHM/view?usp=sharing !

Blender also stores temp files, and sometimes these may not be cleared. You might have a lot of big sym files somewhere.

Try selecting the source of emission set your key frames back to 0 (it must be 0 even if your animation starts on key frame 50) and hit alt+a, this should reset the animation or I might have missed the boat entirely, ether way it doesn't hurt to try

Suggestion like this should probably be posted as comments.

I tried do this, but i don't really see the point with this? the only thing that happens is that it starts the timeframe when i hit alt+a? And the blender still crashes afterwards!

While I misunderstood the question a bit. What happened to me in the past is the particle system would restart but only go up to a cretin point so I reset the animation. I am sure this is not what you meant. Have you checked if you have an Auto-save of your blend before you added tree

Oh okay then i get it! Well I've tried looking for one but i haven't found one so far, so i guess there isn't any unfortunately!

I will try downloading your blend file, and see if I can find the problem, but I am only a noob, I have only worked with blender for 3 years

Hay, I have downloaded your file, I just want to know what the sizes the file is, because google drive say it is more the 202mb but when I downloaded it it was only 2.8mb. Now when I opened it is said that the file was not complete.

Yes I think it should be 202 mb, Im not really sure how it actually got to that size, its sounds like a lot, but i think thats the size anyways!

I was not able to open, the file, I think it because of my computer spec (I am running blender on an old ibm pc) but I am going to a friends house some time this holiday that has a better computer, so it might take some time tell I can give you an answer, sorry for keeping you waiting


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Broken quads, weird rendering?
I have a bit of a problem, at the moment I'm creating a few rocks for game purposes. Im starting of sculpting them and then baking them from multires, and applying that to the lowest "subdivision", just plain hi-res to low-res.
Now the problem I have ran into is that when i use the lowest subdivision all my quads are "broken" and when rendered it looks all weird(I'm attaching a picture of it). And this is not a one time thing, this happens on every rock i create!
Now my question is, how do I solve this? without having to manually change every vert, which i tried but it took like 1 hour, and when i was done i noticed that changing them made a bunch of other quads get broken instead.
And is there a way to get around this completely?
And i have also noticed that this only happens with Cycles and not with blenders internal render!

It looks like the terminator problem

Well, It may be, I'm pretty sure its a render based problem as it only occurs in cycles, but the question you referred to didn't really have an answer! I mean I probably could play around using different light settings, but this is not just for one scene, so obviously the lighting and stuff like that are going to be different for every occasion!

Try adding a subsurf modifier to get more geometry.

Yes That indeed solves it, but still isn't a solution I can use, as the whole point is to have as little geometry as possible!

If subdividing geometry is not an option then I think the solution is to change lighting. One lamp setup isn't good enough. Add 2-3 lamps, increase their size. This will make shadows softer and may (almost) eliminate the problem.

Select your mesh.
In the object mode in the left panel of your 3D view there is bunch of options such as trnaslate and rotate and...
In Shading section you can see smooth and flat button side-by-side.
Click on flat then you'll see your mesh as it is.
If you want to use smoth shading option, your mesh should be hi-res (at least a little bit) or it will be like what you can see in your attached image.
Take a look at this (the same object all the time):

select ur lamp, go to right menu, in properties select sun, scroll down, click to lamp, set size value more than 1 (dont use Hemi fow lowpoly models) and all will be okay (answer for someone who will find this problem fix in google and will open this page)

Blend in a very slight emission shade (eg. strength 0.1) using Pointiness as the fac of a mix shader node for your rock material only, that way you don't have to kill your lighting setup.

Have you tried this?

Go into Edit Mode.
Select all polygons / faces.
Hit W Select "Remove Double"
Hit Ctrl + N
Hit W Select "Shade Smooth"

Note If those triangles disappear as you move your light sources in the viewport.
Don't worry about them they are just viewport's limitations.

Yes Ive tried all of those steps unfortunately! I guess its just a "bug" or as you say limitation! Ive even tried adding more geometry and using edge split modifier, that does help, but still doesn't remove it all! But I guess its just one of those things you have to live with as it seems!

If at all possible do upload the blend file model, I am sure some of us would be interested to look at the trouble you are having and learn something from it.


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How to get around triangles?
Im very new to blender, so this is probably a very simple question, I guess thats why i haven't really found a solution online for it. Ive been working on other 3d softwares that just doesn't handle certain situations the same!
Basically my question is how to skip using triangles when working on a model. for example the screenshot ill be attaching, i have my base of the mesh finished, and then i wanna extrude a part of the mesh which will create triangles or actually in this case even worse, Ngons.
Basically i used the knife tool to cut out the part of the mesh i wanna extrude, i thought about using loopcuts But that would create just so many more faces, faces i don't really need.

Personally, I don't trust the knife tool unless it's to do something very specific. It can make lots of irregular faces if used as a freehand tool. I'd rather stick to loopcuts and not worry about the extra faces.
Judging from your second screenshot, seems like you're trying to make some kind of piece/emblem from your current mesh (which is starting to look pretty weird). I'd recommend to make that part as a different object and then join or parent to your first object.

Well, i agree, its very hard to trust the knife tool, I guess i might use the loop cut instead.One problem though, sometimes on bigger models the loop cut doesn't work as well for me, i guess its because i might not line up all verts like they should, but i might focus on getting my verts to line up better!

Also, on the second part, i would join it if it could be a different object, but really, what I'm doing right now is a jerry can. If you check out some jerry cans, they really have that emblem as part of the metal/surface, so thats why join wouldn't quite work, unless you talk about some other function, that actually join those two as one!

I really recommend doing the piece in your second screenshot as a separate object because its shape goes diagonally, so you're either going to have to use triangles, or end up with a deformed mesh. Also, if you work with separate objects, you can do modifications to one piece without affecting the rest of the pieces when doing things like loop cuts.

Oh, I see now. Looks like the kind of things you can do with textures or bump maps; you could look into that, because modeling that shape is going to be hard.

Well, I'll try using triangles, cause i really need it to be integrated to the model, and the more i think about it, the more i realize how hard it would be to create without any triangles!

Just one last thing. Google "jerry can model" or "modeling a jerry can". You can see images of wireframes (they do look complex) and a couple of videos. Hope that helps.


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Where are IPO curves and deltas?
I'm following an old tutorial from January 2006 (Blender Art Magazine). It mentions IPO curves and delta channels. I'm now working in Blender 2.75a and I can't find any IPO curves except the Graph Editor and F-curves. Also can't find delta channels. Has it changed since version 2.40? If so, how or where to find the same functionality in new Blender?

The online manual states that "In Blender 2.5, IPO Curves have been replaced by FCurves, however, editing these curves is essentially still the same."
https://www.blender.org/manual/animation/editors/graph/fcurves.html
I'll dig more for "deltas" info.
[edit] see this thread an BA it may help you: http://blenderartists.org/forum/showthread.php?219126-Move-Existing-f-Curve-to-delta-equivalent [/edit]
I discovered there is an option "Animated Transforms to Deltas" available through the space bar command search tool, it should derive by this GSoc work http://aligorith.blogspot.it/2011/05/gsoc11-greeting-goodies.html (this is what the last comment in the above cited BA thread refers to)


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How to close a pipe with a perfect hemisphere?
I have a sort of pipe shape which I want to close with a perfectly proportional hemisphere. Problem is the pipe does not have a perfectly round cross-section. It is a little squashed, but still I need to close it with a nice proportional ideal hemisphere. Is it possible?
I tried to pull the middle vertex out with proportional editing, using smooth or inverse square falloff but the result is bad. I also tried to fit a hemisphere, and attach it to the end of the pipe, but the pipe is not a perfect circle.

Using the bevel tool is a simple way to do this. First remove all of the edge loops on the endcap so you just have a single n-gon like this:

Note that I scaled the cylinder to give it an elliptical profile and skewed the face so that it is not perpendicular to the axis of the cylinder. I did this because this is how it appears to me in your picture. If you make your endcap perpendicular to the profile axis you will get a cleaner (more spherical) result.
Be that as it may, I used the Bevel tool which is located in the menu: Mesh > Edges > Bevel with the settings shown on the bottom left of the following image:

Using 8 segments achieves a well rounded result, although as I previously mentioned, the dome shape is distorted because of the angle of the face in respect to axis of the profile. I found that the "Depth" setting worked the best in this situation because I was able to extend the bevel very close to the convergence point without getting overlap. You may want to experiment with the settings to get what you want.
Addendum:
Just to clarify what I mean about getting a cleaner, more spherical result by making the end cap perpendicular to the profile axis, here is a comparison:

Exactly the effect I'm looking for. Very flexible solution too.

LOL, my answer seems like using a chainsaw to cut a sheet of paper in comparison to this elegant fix, nice!

Glad this worked for you. That's hilarious TLousky :) I appreciate the compliment.  I'm a machinist, and I too am sometimes guilty of attacking a problem with brute force when a simpler solution has not yet presented itself.

If you don't need a really perfect hemisphere, you can simply use the root or sphere proportional editing falloff types.
But if you really do, then follow these steps:

Delete all the faces at the tip of your pipe, and fill the tip with one ngon face.

Select the outer edge ring in the tip of your pipe, then use the looptools --> circle tool to make this loop a perfect circle ( W --> looptools --> Circle).
If you don't have the looptools available, activate the addons from the user preferences).

Open a text editor window and paste the following script there. It will calculate the angle of the face from the face normal.
'''
Run This script after you selected the face that should be
replaced with a hemisphere (in Edit Mode of course).
we'll use its normal to align the hemisphere.
'''

import bpy, bmesh
from mathutils import Vector
from math import degrees

bm = bmesh.from_edit_mesh( bpy.context.object.data )
normal = bm.faces.active.normal.copy()

upVec = Vector( [0,0,1] )

rot = upVec.rotation_difference( normal ).to_euler()

print( "Type this into the rotation values of your hemisphere object to align with the face")
print( [ degrees(a) for a in rot ] )

Open a system console (Window --> Toggle System Console) to see the script's output.
Select the ngon face at the tip of the pipe and run the script (press the "Run Script" button in the text editor window).

Check the number of vertices your pipe has and use it to create a UV sphere object with the same number of segments.
Cut the sphere in half by deleting the lower verts / faces.
Copy the angles specified in your system console to the XYZ rotation values for your hemisphere (bottom two lines in the image below).

Select the pipe again and snap the 3D cursor to the center of your ngon (Shift + S --> Cursor to Selected).
Select the hemisphere, then snap it to the 3D cursor (Shift + S --> Selection to Cursor).

Join the pipe and hemisphere (Ctrl + J), delete the ngon you created earlier, then select the two edge loops at the tip of the pipe and start of the hemisphere, then use the looptools bridge tool to join them (W --> Looptools --> Bridge).

This is a very handy method. Good to keep in one's toolbox. However for some reason the rotations are inaccurate. It didn't match. Also for some reason LoopTools won't make a perfect circle out of the ending. It shifts only very slightly, though I tried various settings.

I would do like this:

Select the end face(s)
ShiftS > Cursor to selected
ShiftNumPad 7 (Align view to faces)
Add a sphere:

Set the number of segments, the radius etc to match the tube
Check "Align to View"

You might need to rotate the sphere to match the tube
Remove the unneeded part of the sphere and the end face(s) of the tube¤
Select the half sphere and the matching vertices of the tube
Press W > Remove doubles

(¤ Do this while the view still is aligned to the end faces. Tip: Enable vertex snapping (hold Ctrl) while rotating.)


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Render wireframes with hidden wires?
I need to render my models in wireframe (no solid). I first turned to the Wireframe modifier, it works great. Only I can see through to the wires at the back of the model. I need to render only the front-visible wires, otherwise it just clutters the view. Is it possible and how? (No matter if it's BI or Cycles in this case.)

Have you tried to adjust the Clipping parameters of the Camera?

I don't think that will work as I have 2 rows of models, one behind the other, so I need to render front-wires of both rows, and hide back-wires of both rows.

Ok, I played some more. And I found an acceptable solution. I use the Wireframe modifier. I set it to solid (don't replace original). I set 2 materials on the object, white and black. Set the solid to white (emission shader) and the wireframe to material offset +1 (meaning black). And I get a nice clean geometry with only visible wires and edges.


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Depth of Field F-stop not doing anything?
I'm trying to achieve DOF using Blender Internal 2.75a. Everything seems to work, except that the F-stop doesn't seem to do anything, nor in the Defocus node nor in the camera DOF settings. I just get a uniform blur, no focus plane. I followed tutorials and read some posts but couldn't find the correct solution. See the image for my settings. Note that I am focusing on the Eyes object. How to make it work?

I don't think the defocus or vector blur nodes expect a normalized Z pass. What happens if you delete the normalize node?

When I remove the normalize node it sort of inverts the effect. There is no blur, and I have to turn off use z-buffer and it gives the same blurred result as before. Uniform blur. And F-stop in the Defocus node is then greyed out.


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Compositor Backdrop disappeared
I have a little, though important issue with the Compositor. I had a Backdrop and everything worked well until I wanted to check what the Viewer Border checkbox does (red in the image). I clicked, the backdrop disappeared and I can't get it back in any way (unchecking the checkbox won't help). I also checked that it is file dependent, in a new file everything is ok. What to do?

sometimes it helps to ctrl-shift-click on the node again where you want your viewer node (auto-)connected.

yes, this I tried, but it still won't show up

hm, no idea then. i tried to recreate it by using that viewer border checkbox, but the backdrop still worked. if it's only your file, as you say, maybe transfer all the content into a fresh one?

Does it show nothing also if you connect other nodes to the viewer output? I see lots of nodes working with alpha and your render layer doesn't have a preview image. Are you sure that there is something to backdrop?

try ctrl + alt + b and fit operator.

@Carlo: I double checked connecting the Viewer to other nodes, and you were right, my mistake, it is due to the lack of preview in the RenderLayers node. Somehow there is nothing to backdrop. Ahhh! Got it. I had to turn off the sequencer in Post processing, and there is a RenderLayers preview again. It renders again! Woof, problem solved! :-)

Good! Consider to make a proper answer with what you discovered and mark it as accepted. Here in the comment is quite hidden.

Ok, so this is the solution. I had to switch off Sequencer in the Post Processing tab. I had added an image-sequence to the sequencer at some point, which made the Sequencer rendering take over over normal 3D scene rendering. That is why the RenderLayers' node preview disappeared and consequently the backdrop, as there was nothing to display (from the last node in the hierarchy, I checked other nodes and they did display bits and pieces as should be). I somehow connected this behaviour with the Viewer Border checkbox which I checked and I got confused, but it seems it had nothing to do with it. Now that I have the RenderLayers preview and the backdrop back again, I can't replicate the behaviour of Viewer Borders affecting my backdrop.


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How to bake alpha in Cycles?
I'm preparing to re-model a Table Mat (like a Tatami Mat) tomorrow. I will need to do some baking from geometry onto a plane-texture. I know how to do that, except I don't know how to bake the alpha? I don't see alpha in the list of what I can bake in Cycles. There is transmission, but I think it's not the same. Is there a way to bake alpha? I'm pretty sure I will need it to compose materials in the Compositor. Would it help if I set world color to transparent in the Film tab in the Render properties? Will it then bake with transparent alpha?

I don't think it's possible to bake alpha directly, but you can try making a new shader mixing a white and a black emit shader together using the alpha of your textures as mask, then bake that into a new texture.
It will be a bit tedious if your scene is too complex, but I don't know of any other way. If you have too many objects it's probably a good idea to try to automate that using python.

For cycles what I did was bake 2 times creating 2 textures, 1 the regular bake texture and the other is just a glossy bake type, only the color and that created a B&W image that then you can use as a mask in photoshop...

leave your alpha node plugged in, and bake with combine to your texture. Than alpha output works from your base color texture image.

Maybe its off topic, but I was just playing around and it may be helpful how to bake UV background as alpha
Once you set your material bake it

Save picture with these settings

Bake it again, and here you have UV alpha background

Here result

I'm not sure what you need but I believe you should be fine just baking the textures and use it as diffuse while using another texture with alpha information on the same material to provide the transparent areas.

authors: سلومي بومحمد


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Cant select/move multiple keyframes even with B select?
Ok, it is very inconvenient in the dopesheet trying to move multiple keyframes but only able to move 1 - even when a batch has been highlighted orange.
Per other answers Ie used the B key to select multiple:

But then when I try to move them with left mousekey, only 1 moves at a time. Is there a way around this?

The dopesheet behaves similiar to the 3D view.
The right mouse is used for selecting objects or keys. Incidentically, the RMB followed by a movement before releasing the mousebutton selects an object/key and immediately enters the translation operation.
But since you only want to do a translation, you have to initiate it with a shortcut as intended. The correct way is to do a box selection and then...

make sure the cursor is hovering in the dopesheet (so it will receive the keys pressed and not some other window; Blender is context sensitive)
press G (grab) to enter a translation operation (G key down and up)
move the mouse, (moving the keys)
press the left mouse button to confirm the operation and exit the translation.

OR
4a. press the right mouse button to escape the operation. The keys will snap back into place.

BTW I think select multiple keys and lost this selection while moving is not intuitive. Anyway I love Blender! :-)


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How to make infinite mirror room in eevee?
Alright I looked at Making a realistic infinite mirror tunnel and am trying to make an infinite mirror room in 2.8 eevee.
The answer says to increase light path bounces, but obviously this doesnt apply in eevee where lighting settings are limited to:

What Ive tried is making a mirror material (100% metallic, 0% rough) and put a reflection plane on every wall. I then upped the distance to like 5m on each -

however I still get maybe one reflection of the center object at best.
How can I do this in eevee?

Looking for answer to this question I found this
https://www.reddit.com/r/blenderhelp/comments/nb3niz/how_to_see_mirrors_in_mirrors_in_blender_eevee/

I'd like mirror reflections to be visible in other mirrors in Eevee.
Can I do this with the kind of mirror that relies on reflection planes
and principled metallic materials with backface culling (in this case
in the shader but could have been set in Material Settings instead)?
Currently, mirrors appear in other mirrors as grey surfaces.

And in general the answer seems to be

Eevee can't do this.

I do remember seeing a script that took the output of a camera in the scene and showed that on a surface - making it function as a mirror, and perhaps allowing it to do more than reflection planes. But I can't find it anymore :-/


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Is there a way to displace or randomize shape of metaballs? Achieve effect like this?
Ok, Im trying to create a cartoonish effect in eevee somewhat like the fire and the energy ball by Violet here -

Specifically what Ive tried so far (to mimic specifically the distortion on the energy ball by Violet) is a particle system emitting metaballs of various sizes and at various velocities, so they merge together to create an oddly shaped blob:

Issue from here is, I want the sharp edges/additional distortion that the above example incorporates. Mine is pretty uniform just spitting out meta balls.
How can I distort a meta ball particle system or achieve this effect otherwise? I cant apply a displace modifier to the meta ball so I dont know where to go next.


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Shapekeys - Meshes have same number of vertices but still get error "mesh must have same number of vertices"?
Alright, I had 2 identical meshes and slightly modified the vertices on one. I need to join the other as a shapekey on the first. So I decimated one so it has exactly the same number of faces as the other, as measured by decimate modifier.

Yet when I do the "Join as shapes" shapekey option, I get the same error  "mesh must have same number of vertices".
I have applied the decimate modifier. What is wrong here?

Same number of faces doesn't  correlate to same number of verts.

Ok @batFINGER so how would I get same number of verts to do this?


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How to get fluffy material like this - do I need hair particles or just material?
Alright, this is a Blender x Substance question but all ties back to Blender materials. Ive been trying to nail something like this (NOTICE the little stray fluffy hairs on the surface of the cloth material.

Ideally I'd like to achieve this with material alone, and I know this material was made in Substance. I've looked everywhere and can't find a great cloth material for Substance or Blender that has these fuzzy hairs, and actually looks realistic.
How can I do this? Do I need to incorporate a hair particle system?

Hello :). Simon Thommes made a great procedural knitwear shader. It uses microdisplacement for that fluffy look.

The closest result I managed to find was this tutorial:
https://www.youtube.com/watch?v=T8NT5Bth450&t=301s