text:
How can I paint a mesh using projections of real photographs?
We have a series of real (not rendered, taken using canon cameras) photographs, arranged roughly in a sphere around a real world object.  We have used various Structure from Motion techniques to figure out precise camera pose parameters (position, quaternion, focal length) for each shot, and using that information, we successfully "scanned" this object into a mesh.  For instance, I've had a great deal of luck taking the camera information into Blender with the mesh, creating a virtual camera for each of the real world cameras, and rendering depth maps that lineup perfectly with the original photographs.
We're now interested in attempting to texture the mesh using the original photographs.  Conceptually this is simple; I position the cameras in Blender around the mesh just like I did for depth maps, and turn them into projectors (think old school slide projectors), projecting the photograph from the real world camera each represents back out onto the mesh.
The target output of this is a UV-mapped texture+mesh I can take out of Blender and into another environment, such as a game.
Can Blender do something like this?
I'm very new to Blender.  I'm aware of both (http://wiki.blender.org/index.php/Doc:2.6/Manual/Textures/Painting/Projection) and (http://wiki.blender.org/index.php/Doc:2.4/Manual/Textures/Painting/Projection), but at first glance this appears to be an artist driven approach rather than a mechanical one.  The end result is something we can hopefully automate in python, since there are many images.

This can be done manually, by using a brush to paint the projected texture, however I am not sure of the details.

or baking the projected texture on mesh's UV texture.

You might be able to use some of the techniques from this tutorial on camera mapping.
Namely, you may want to try using "Project from View" to project selected mesh faces' UV coordinates based on the current camera view. I've never tried using it via scripting, though.


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How to hinge an object and apply physics?
I'm trying to hinge a modified torus to a hole made to a modified cube.
Torus: physics: rigid body | dynamic ON | Collisions shape: Mesh
Cube: physics: rigid body | dynamic OFF | Collisions shape: Mesh
But during simulation the torus simply flies off, instead of hanging.
[Model screenshot attached]
[]1
Blender version: 2.73a

Your described set up works fine.

The Rigid Body World

The dynamic chain element

The static collision object

Start trouble-shooting

Double check your settings.
Create a duplicate of your file and delete everything except the problem area.
Create the scene from scratch and append it to your file.
...

I started from scratch again for the problem area. Now it works. Thanks.

Earlier, I made the objects small (few cm). May be that's why it failed.

I changed the sensitivity margin under Rigid Body Collisions to an appropriate small value. Now it is working.

Your*

Also, sometimes hitting CTRL A helps too.

source: Stack Exchange

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

authors: Вадим Тютюник

sort: votes


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Skin modifier giving wierd geometry
I am getting weird geometry when i try to add the skin modifier to an edge. Im following the tutorials but my starting result is off.

to few vertices.

Thanks for the fast response. Doesnt matter how many verts i add to it i am still getting bunch of extra geometry. started with one single vert extruded it out 10 and 20 times and im always getting these in one way or another. So far this is my only issue with blender that ive had.

@kajillin try selecting the vertices with the mess and click Mark loose  in the modifier

Discovered it was a scaling issue, What im importing into only likes things scaled way up from blender. Set scale to defaults and it is working normally. Is that normal?

I think so... would you put that into an answer so we can get this question off our hit-list? Thanks

Scale was set too high for the modifier, which was putting the vertices way to close to each other giving me errors. Seemed starting at the default scale while building the mesh, and then scaling it up afterwards still enabled me to use the scale i needed for importing.

You can apply the scale of an object by pressing Ctrl+A > Scale.

This way you do not even need to re-make your mesh at the correct size, or scale after using the modifier. You can make it the desired size, apply the scale, and the modifier will work correctly.

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


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Mesh only moves in Blender units
Im new to blender, so please explain the answer clearly. I don't know what I did, but now, my meshes only move in Blender Units - it's understandably annoying. The only way they move more or less freely is when I hold the control Key.
Using blender 2.72b

This is from snapping. You must've accidently turned it on. Click the magnet again to turn it off. You can find it at the bottom of the 3D viewport (the main window.)

When you know it's on, snapping is a helpful tool to move stuff exact distances without having to type it in.

Actually it's completely common. When I first started blender I got stuck cause I didn't know how to delete the cube. And I didn't know what the lamp was.

Been there


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How do you fix hair stretching?
Okay,so I am making a fan model of Ezio Auditore and I added hair.

But the strange thing is that when I started combing the hair on the base mesh I made of him in MakeHuman,the hair particles started stretching irregularly and i had the Comb tool selected.

Can anyone tell me what's going on here,please?

Clarification needed. Did the hair particles started to behave like that right after you imported the model in MakeHuman, or did it start when you start combing? Also consider uploading your .blend to http://blend-exchange.giantcowfilms.com/ and adding the given link to your question.

Have you checked 'use modifier stack' the particle settings? The modifiers order may be also the key to solve this issue.

might also be related: http://blender.stackexchange.com/questions/58541/problems-rendering-hair-in-cycles-render/58571#58571

No,that didn't work.

And maybe the reason is because I imported it with MHX2 hair particles.
That could explain why this is acting so strangely.

Figured it out,it was the file its self.
I appended the model into a new file and now it's working perfectly,but there is still one more question.
How do you make Ezio's hair shape in blender?


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How can I find the proper focal length of the cameras in Five Nights at Freddy's using BLAM?
It's been a long time since I last posted and I need your help. For a few months now,I've been trying to find the focal length of the security cameras in Five Nights at Freddy's. Every time I tried,it was always inconsistent. Then,I found BLAM (which I'm still unfamiliar with) and I tried using it to solve my dilemma,but it didn't work either. Could someone please help me?
P.S: I heard that BLAM has a new predecessor called fSpy. Should I use it instead?
Here's an example of some rooms from FNaF2 that I want to replicate in Blender:
1. Main Hall

2. The Office

3. Parts & Services

Download and watch this. Its Free. https://blenderartists.org/t/perfect-photo-and-camera-match-with-fspy-and-blender-2-79/1135878

Thank you. I'll watch it when I go back home.

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


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How do I use IES lighting with a sphere?
( Hey,everyone! I'm in a bit of a pickle. I created a wonderful IES node setup thanks to an amazing tutorial and it works with planes and circles. However,I'm having trouble with one mesh in particular,the sphere. When I use a sphere to try and light my scene,its curvature the light scatters incorrectly. Could someone please tell me what can I do to fix this dilemma?
Lights

Plane:

Circle:

Sphere (specifically,hemi):

Node Setup

You hide a circle inside the sphere. The sphere does not shine into the scene, but is only visible to the camera. The circle is not visible to camera, but shines light into the scene. Second approach is to modify normals of the sphere with a custom normal data so that all of them point down in single direction, like on a plane.

No,I actually rendered the meshes separately. The sphere is all by itself.

I know, I am not describing your setup, I am proposing a new one. One where there is circle inside sphere, or a sphere all by itself but with changed normals.

Oh,sorry. I have a tendency of seeing things in the wrong way.

Thanks to a little advice from my commentor,Jaroslav Jerryno Novotny,I figured it out. For the first Mapping node connected to the Geometry Normal socket,change the Z-axis scale from 1.000 to 0.000. I know you're facepalming right now because this question was stupid and it had an easy answer,but c'est la vie.
Solution

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


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How can I make Perspective view resemble Orthographic view?
everyone. I'm back.

I'm creating the torso of my game character,Tanya...and I was wondering how I can make Perspective View look like Orthographic View. I saw this teaser that Emil Macko created for FNaC2 that struck my fancy and to me it looks like Orthographic view. I want to implement this so I can properly model Tanya. Can someone please help me to replicate this camera setting?

If someone helps me,I'll give them a big thumbs up.

I meant that I wanted it to be the same as this camera setting above. I need this to properly model Tanya.

Press NUMPAD-5 to switch between perspective and orthographic view in viewport. Go to the Camera settings in the properties window with the camera selected if you want to change your camera to be orthographic.


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How can I change the camera to include more of my scene?
As you see in the picture I am looking at the room modeled through the camera perspective:

I want to change my camera settings to be able to render a picture of the whole room. How can I do that?

you can change the focal length of your camera to a lower value like 24mm.

Just keep in mind, that a lot of the time, you don't want huge focal lengths in your renders. I can make a much less pleasing image, because there is less focus, and your trying to show off your entire scene at once which can b extremely distracting to look at, especially if it's big and has a lot of detail, instead, you should probably find a few elements in your interior, and try to make a few images, that focus on those objects. This should result in much more pleasing images. But the answer to your question is below.

Focal Length is the correct term, and is different from Focus distance. No one uses Field of View when talking about a lens in real life.

This is the Default 35mm frame

There are two ways you can bring more content into frame.

Lower the focal length of the camera, in this case from 35mm to 25mm

Back the camera up (I prefer fly mode over grabbing because I can see the result while doing so)

Go into fly mode, shift + f,
do not move the mouse while doing this (otherwise you will change what you are looking at)
back up, s

Note that cameras with a low focal length can look weird, look at this 10mm example

For large fields of view, you could also use a panoramic (fisheye / equirectangular) camera. In particular, you'll need a panoramic camera if you want the field of view to exceed (or even get close to) 180 degrees.

Focal lengths are good, but what I find useful for many of my projects is opening the menu by pressing "n", go into camera view by pressing 0, and then enabling the "Lock camera to view" option.  This will allow you to change the camera angle just as easily as you normally can in the viewport.


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large scale modelling, numeric problems?
I would like to create some models on the scale of 1-10k blender units. I remember reading somewhere that modelling on that scale can cause numeric problems. Is this correct?

related: http://blender.stackexchange.com/questions/3168/digits-of-precision-of-vertices-coordinates

The emphasis of Blender development is Artistic, and not high precision modelling like is expected from dedicated CAD/Engineering software. This doesn't mean you can't model or represent big things, but it does mean that you are limited to a level of precision in one mesh.
To get an idea about precision read Ideasman42's response to Digits of precision of vertices coordinates . The technical answer to your question can be found in this response.

Another resource which can really give a sense of the relative scales we're talking about is Alex Januszkiewicz's Article On AutoCad Accuracy. An excerpt:

If you try to do a drawing that extends 4 km in each direction, Microstation's 32 bit format will limit your accuracy to 0.001 mm. The same size AutoCAD drawing can be drawn with an accuracy of 0.000000001 mm, that is one million times more accurate.

This refers to 32 bit Single Precision (Blender uses this) vs AutoCAD's 64 bit Double Precision storage.
The link for that text may not be available permanently, but if you google  "Alex Januszkiewicz AutoCAD accuracy" you will find it.


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Can Blender render pngs with the background transparent?
I would like to render an animation as a series of .png images with transparent backgrounds for use in a video. Is this possible?

One of other settings that can mess your transparent background is something in Composing tab. What I did was set perfect white color there with this tutorial: https://www.youtube.com/watch?v=aegiN7XeLow And then browse half of the internet, figure out to find the tutorial how I set perfect white background, and than discover I have to remove the middle box from Composing tab. To future me: I got that covered

Yes this is possible.
To save rendered images with transparent background (PNG format for instance), the settings are as follows for "Cycles" and  "Blender Render" rendering engines.
Cycles
Properties Editor > Render Context > Output Panel
Choose RGBA so that the alpha from the renderer is saved in the png
Properties Editor > Render Context > Film Panel
Check Film>Transparent so that the World background is transparent.

Blender Render
Properties Editor > Render Context > Output Panel
Choose RGBA so that the alpha from the renderer is saved in the png
Properties Editor > Render Context > Shading Panel
Choose Transparent Alpha type.

EEVEE (Blender 2.8)
Properties Editor > Render Context > Film Panel
Choose Transparent Alpha type.

This is the answer.

It's not working for me (Blender render) and I chose the same options. When I render, all I see is white (the material color).

One year after, and yet again it helped me.

Why does blender still spend render time with the tiles on the transparent parts?

@Anson What I believe is that the camera is shooting rays into the scene and since there is no returning ray , there must be a timeout wait before the render decides to move on to the next square.

The funny part is that this answer, while covering how, fails only on suggesting PNG as a format. PNG is incapable of preserving alpha from a render because it uses an unassociated alpha format. It is likely precisely because of this that the PNG format has almost exactly zero uptake in visual effects and imaging circles.

@troy_s You sound like you know what you're talking about, and I'm curious to hear it. Why don't you edit the answer to include some of your insight?

I can't because the answer is a bit of a trap; PNGs can never render transparency correctly from a technical vantage. Best hope is to educate the imagers around these parts so that they can become aware of the differences in alpha format, and the impact on their work.

@RegularJoe As you can see from my answer, the Film panel is Cycles renderer specific. It does not show up under Blender renderer.

@Satishgoda, this is a VERY USEFUL information and thank you.

@Hikariztw, in Blender 2.8, the Film and Output panels are in two different locations.  The Output panel has been moved from the Render context to the Output Context.

@mattthew Yeah, I do find out that thing after I press the submit button. Going to add it.

Thanks for updating also to Blender 2.8 (Eeevee) - very helpful!

I'm using Eevee with Blender 2.8. I clicked the "Transparent" checkbox in "Film", and I also tried changing the "Alpha" setting of the material, but it's still not transparent.

Make sure there is no geometry that is obstructing the background.

PNG is a broken format and cannot encode things like reflections, glares, flares, fire, etc. Emitting yet unoccluding pixels are simply impossible to encode using the broken format.

In Blender Internal, If you want the background to be transparent, you can change the output type to RGBA and in the Scene tab under Layer, untick Sky.

Unticking "Sky" was what I needed to make it work (I already had RGBA selected). In Blender 2.79 I found this setting on the "Render Layers" context.

In the render settings go under Shading and set alpha to transparent. Then under output click RGBA. Unchecking Sky in the scene tab will also work but I'm not sure if that method will have an impact on any other parts of the render or if it's just a redundancy.

Where do you see that? I don't see any Shading section, but I do see Sampling, AO, Bloom, DoF, Subsurface Scattering, SSR, Motion Blur, Volumetrics, Hair, Shadows, Indirect Lighting, Film, Simplify, Freestyle, and Color Management.

when using luxcore render in Blender, in Camera panel, turn on checkbox 'Transparent Film' (settings is different for each camera)

in output panel, choose PNG format and RGBA (alpha)


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How should I handle a split in a retopology?
What's the best way to handle a "split" in retopology? Consider the case of a torso splitting into legs:

In this case, each leg ring is made up of 16 vertices, as is the torso ring. What is the best way to attach these together with clean topology to create a good retopo?
This also applies to standard mesh modeling: what's the best way to create such a split with polygon manipulation?

Are triangles ok? If you are making this for a lowpoly model (computer game), triangles are ok. If you are going to subdivide it, they are not (probably).

@Gunslinger it will be subdivided.

it makes things more complicated but my answer below should work.

First step. Make flaps bending down between the legs.

Make a strip between them and make several loop cuts. You may have to experiment to find the correct number of loop cuts. This is important if you want to have an all quad model. The total number of edges around the opening must match the leg.

Round out the strip to match the correct shape.

Select the two loops and bridge them. If you have the correct number of loop cuts in the strip between the flaps, this should be all quads. Else you will get triangles.

Further adjust the geometry to make the bridged area more even.

Final result:

Very clean. Nice.

This is how I would do it to maintain Quads, and hence good edge flow.
As you see I did it in half first, always easier than repeating yourself.

I dont think that your edge flow is all good. Around the diamond shapes it will go vertical, around the diamond, around the leg horisontal, around another diamond and then shift down. It will be hard to make additional loopcuts on some places. Also, the face loop will follow the same pattern in some places (up, around and down).

@Gunslinger: even so, the answer describes the work-flow quite well, and the user can tweak the edge flow to their liking.


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Is this bug with addon
I have downloaded the Smart Join addon
Blender File
I'm having problem with the add-on for this model. When I click on Separate S Join the model or mesh is deleted. When i click on expand smart join there is a empty cube only no mesh inside. I do not want to Apply smart join. How can I separate my mesh with our without the add-on?

Is there a post/documentation that provides a little more info about this addon? The website provided in the repository info links to some Chinese language online lottery.

@GiantCowFilms i have given the link of addon https://bitbucket.org/aivanis/smart-join/downloads/   and not online lottery link

I was looking for additional information - I was just pointing out something was weird with the repo owner's site. As it stands I don't have much info on how the addon is supposed to function exactly, which makes it hard to determine the root cause. "Separate S Join" is not an entirely self-explanatory name. What source did you use to determine what this addon will do? Perhaps what is happening is expected behavior? Without basic documentation, its hard to find out of its user error, what the user error is, or if the addon is not doing what it should.

@GiantCowFilms this is an video which can help how the addon works https://www.youtube.com/watch?v=VaPPLJigrgY

Thank you, I think this is more answerable now.


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set temDir and outputpath via python script
I have to use blender 2.49 and I am trying to change a few settings via a python script like resolution etc. - everything is working but the tmpDir and the outputpath - which I want to change from /tmp/ to /local/ for example
I am using the blender 2.49 api and it should be:
bpy.config.tempDir = "/local/"
bpy.config.renderDir = "Path I want"

but this is not working so far.

Out of curiosity, why are you srill using 2.49?


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How to make the Glossy material in Blender not too dark?
I was making a 3D eye and when I added a glossy material to the model, the light looks great, except for the fact that the model looks too dark. Is there any way to fix it? Maybe add a better material setup for it? (I need a fast/quick material, not a complex one, I have very little time)

Try adding a diffuse shader as well. And double check your lighting.

Make sure the color of the glossy is white.

@VinceScalia Go ahead and add as an answer for the answer ratio

oookat. answering

@NoviceInDisguise If he adds the answer UV.

You can add a Diffuse shader to your material. The color of a Glossy shader is influenced by what is being reflected, so having a Diffuse shader underneath will make the color more consistent across the entire mesh, in all settings.

With a 100% white input, here were my results:
Just Glossy:

With Diffuse:

True, but he might just wan't his mesh to be that reflective, in which case this may not work... But it is nice to avoid having to create/find an HDR.

Most objects are not 100% reflective anyways I have noticed. No matter what lighting, you can always tell the color of it. Especially something complex and organic like an eye.

I agree he should add a diffuse texture, but It is useful to have any degree of reflectiveness visible, which is more what the question is.

True. I agree with that.

You need the change your background. It is currently reflecting the sky, wich is that dark grey color. I would recommend adding an HDR image To add reflections etc.
Without HDR:

With HDR:

No lights or materials were changed in the setup.
Adding A HDR Background:

Set the works "color" to environment texture. You may need to raise the strength to make it bright enough.
You can still have the grey background with a little hack if you need it:
Simply add these nodes to your world material.

Not-Ideal HDR work around
In the case you don't have an HDR, you can use this workaround. The reflections will be less realistic, but it still works well.
Add these nodes to your world material:

Result:

Make sure that the color of the glossy shader is set to white, either with an external color node (as seen in @NoviceInDisguise's answer), or with the color setting in the glossy node itself.


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Premade Materials in Blender render?
Does Blender Render have pre-made material like a chromed/metal material like other 3D softwares like 3dsMax or Maya? I know that there are more options on cycles, but does the blender render have this too?

Ni, BI doesn't have a material library included. We collected links to resources here: http://blender.stackexchange.com/questions/15355/resources-for-blender/15361#15361

@cgeaton That is a cool link, but I think the addon only applies to cycles, or did I miss something?

No, there are no templates so to speak. You can create or buy your own templates though, and bring them into your project using blender append functionality. The blender foundation announced a project to improve this system.
To create your own template library, open new blender file (you won't want other work in here). create a bunch of spheres, and build the materials you want. I recommend naming them carefully, since you will be pulling them by name alone.
Once you have your library, you can link or append the materials, I recommend appened, since it allows you tho change the materials in your .blend, while link you have to change them in the master, and it will affect all the files using that file.
To appened, go to file > append or hit Shift+F1.

and navigate to your .blend with the materials in it. When you click on the .blend, you will see allot of folders. Click on the one called material

You will see the names of your materials. select the ones you want for your project, and then tweak them to your needs!


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what is the best way to merge the double vertices lines in a plane to sphere object without loosing the plane UV map setting?
when i use the self created plane to sphere object , i still have to deal with the double lines from start to end borders from the original bent plane .
in the picture we can see the lines are double where they will touch eachother.
in the second picture we see the final result with the sphere using the plane uv map,
now is that still available when the double start to end border lines are merged ?
or is this impossible ?
what is the best way to merge these double lines and still have the plane uv map working?

Use W>Remove doubles to join them. Next, use Ctrl-E>Mark seem along the verts to allow for separation, basically joined edges will always remain connected, messing up your UV map, unless you specify otherwise with mark seem. Finally select everything in the UV image editor and hit P for pin to lock 'em in place. When you UV unwrap again, everything will be in order.

i works great , thanks but i have one more question about your answer, i have exported the file , and imported it in a new project , i took a look at the uv map , and it was exactly how i hoped it would be, it is the uv map from the plane, perfect ok , but if i change the uv map for a moment to see another setting or possibility , it seems i have lost the plane uvmap , and i can only get it back by redo my steps , or is there another way to get the plane uvmap back to where it was , after i changed it for another unwrap ?

also could you say "Mark seem along the verts to allow for separation."in other words ? i try to understand what you mean exactly. specially the part :" allow for separation"

you made the answer as short as possible with a few words and i have to guess exactly what it means..

@elmentor What do you mean by "exported the file", did you save it or did you export it to another software package

i stay only in blender. i exported the file as an object in a folder and then imported that object again in blender to see what happens. and than like i said , i found out the uv map is lost at the moment i am trying another unwrap for experimental purpose. the only way to get my original uv map back is to redo my steps, or is there a way to recreate this uvmap again after when i changed it ?

@elmentor Are you exporting your UVmap? if you don't know how that would be a separate question. What does the UVmap look like when it is imported? What format are you using

for import/export i use object files only.  when the sphere object is imported , the attached uv map looks like a square , exactly like the plane. it stays like that as long i don't go experiment and try other unwraps. or the square uv map will then change into another  kind of form. after changing it now i want to go back to my square uvmap that i originally had, but the only way to get it back is to undo my steps , is that right or is there another way ? can i for example import a plane uv map into a sphere object ?

@elmentor Use p to pin them if you don't want them to change. The pinning isn't exported with the OBJ format, I would recommend not using it for transferring parts of blend files, use linking and appending. My answer cannot be expected to support export formats, it isn't possible to lock a UV through OBJ

i am gonna study how the pin has to be used exactly. i hope that is the solution i was looking for.

@elmentor This is the best possible solution you can get. If you export your UV map, it will change if you re-unwrap, since you simply cannot export the settings. Its simple: If you use .OBJ and you try to un wrap again, it will change

it makes sense that you loose the uvmap and cannot get it back in the square shape that you had before unless you do the undo steps to get back , and there is no other way to recreate them again. i understand. i might use the pin function as you say , but best of all , i suggest i just leave the uvmap at its square form , and not gonna touch it...that should be fine then.  thanks for explain.

another handy way to move edges around on closed objects is edge slide with preserve UV checked.
It helps in cases *Almost like this....
Fiddling with edges on a closed shape to hand decimate.

i didn't understand this edge slide solution , but never mind , the first answer totally worked for me.  ("W"to remove doubles and Ctrl E ,mark seem etc )


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Unwanted lines showing up on rendered cube
So I have a "twisted" cube that I rendered an image from, as shown below:

I was wondering if there is a way to smooth out the diagonal lines on the cubes faces.

Set the smoothing to smooth and in the mesh properties check the autosmooth option and set the angle for cca. 60°. You should also densify the geometry

What he said ^^ A face is treated as two triangle internally in Blender for rendering and such otherwise

or you can simplesubsurf it.

Just because I want to learn, and understand... This is because the middle edge is marked as sharp?

Yes, setting it to smooth should fix that issue.

@Jerryno you may want to write your comment as an answer

Every quad is treated as 2 triangles, this is what is causing the problem. You need smooth shading for the edges inside the quads and sharp for the corners of the cube.
To do this set the smoothing to smooth and in the mesh properties check the auto-smooth option and set the angle for cca. 70° (depends on the twisting).

This way faces with angle with more than 70° will keep sharp shading between them.
You should also densify the geometry so it follows the ideal curved/bended surface closer.


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Several shape keys blocking mesh face trasformation?
I newly started using shape keys to create an animation, which is just a cube wobbling on the spot, the first shape key that I applied was the top face of the cube rotating slightly, and to this point it went all good. Then I wanted to add another shape key, making the same face rotate back to place. When I created the Shape key, I went to Edit mode, but when I tried to rotate the face, it wouldn't move at all. I could see the dotted arrow as I usually would when rotating, while the face remained still.I tried using the hot keys (R -> Z), the Mesh tools -> transform, and 3D widget manipulator and all of them resulted in the same. I tried to do the same thing to the first Shape key and it worked, while the second did not, even though both seemed to have the exact same settings

You probably enabled the option which allows you to see the applied shapekey in Edit Mode.

Please set the shapekey value up to 1, and then edit the mesh or just disable this option.

Ok so i put the value to 1.000 so I could edit the mesh and set the standard for the shape key. The thing is, when I move the value to 1, the shape simply shrinks all the way, dissapearing completely at value 1.000, making it impossible to transform. Is there any way to "reset" the shape key in any way?

here are some pics: link

Could you post your .blend file via pasteall.org. It would be easier to help you then.

ok I uploaded the file as "Spinning jello". I hope I did everything right since i have never used PasteAll.

Please post the link to your pasteall file.

There seems to be an error uploading the file... even though it worked last time.

Ok here it is: [link]http://www.pasteall.org/blend/34999

Sorry for not responding for a long time. I saw the file and you should probably delete the not working shapekey using '-' symbol in shapekeys panel and try to add a new one and edit it properly once again.

Ok awesome, thanks for your time and patience!

@Olibrot if this does answer your question please mark it as accepted


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How do I delete one single shape key?
So I added a shape key, but later I had no use for it so I decided to delete it. So I went to the Blender wiki and read the shape key article, which clearly stated "The "X" button: It allows you to delete the current key". So i did exactly that, but when i pressed X nothing at all happened. I also tried using the "delete" key on my keyboard, with the same result. So how can I delete the Shape key?

Shape keys can be added and deleted through the Properties editor (the on the right ) under the Data tab in Shape keys :

Is there a particular reason why the minus sign is grayed out when not in Object mode? I just spent awhile struggling with this while in Edit mode.


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Strange lines appearing when rendering glass
My scene is a cube standing on a checkered plane. For some reason I don't quite understand, when i render the final product lines will appear on the cube, as seen in the picture:

What really bugs me is that I rendered another picture awhile ago, with pretty much the same settings (quite close at least) but this time no lines appeared! Unfortunately the blender file that came with this picture was deleted, making it impossible me to copy from:

it would be useful to show the material node setup, the render tab (light path settings); which render engine you are using, or if you can upload a .blend file

actually the problem is gone! I simply deleted all textures and made them again from scratch... so I guess we'll never find out what it was..

actually, i have another blender file with the same problem, it's nearly the same as the one in the picture, only with some different colors and lighting, here's the link for it: link

it's the cube intersecting the floor rise it up a little and it should be clear; here is a render

OMG thank you so much! thx for your time!

The cube was intersecting with the floor which created this effect :

Select the object and hit G then Shift and move the mouse up slightly
or you can enable face snapping and move the cube to place it on top of the floor plane

Here is the render after moving the cube


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Py: List materials with texture used by mesh
I have a script that list vertices and faces but now I need to get the texture associated with each face, known that only one texture is in each material , only one mesh is in the scene and it is selected .
I only found the way to list the texture associated using the uv image editor ...
Thanks

Using blender internal, a material can use up to 18 textures to get it's final appearance. An objects face can have one material assigned to it, any and all textures in that material are used by the face.
In object mode you can get the texture used by each face with
obj = bpy.context.object
for f in obj.data.polygons:
    for t in obj.material_slots[f.material_index].material.texture_slots:
        if t is not None:
            print("Face %d uses texture %s"%(f.index,t.name))

Of course this is using Blender Internal, for cycles you will need to walk through the nodetree to find the nodes your interested in.

It's almost that. It displays the texture name, I didn't say but I need the texture "filename", I don't find how to get it now...

I just find that obj.material_slots.material.texture_slots[0].texture.image.name give me the texture name with .00X for dupplicate, I think I can work with it...


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'Mesh' object has no attribute 'uv'
I'm trying to update an old script and I'm near to achieve my goal but I'm locking at getting uv coordinates because the old script used the texture assigned using the UV image editor and the new one need to use the texture assigned with material.
Then the thing I don't find is how to get the uv as easy as the vertex coordinates.
This is the code I have to get faces:
face_count = len(self.ob.data.polygons)
print("face count: "+str(face_count))

for f_index in range(face_count):
    uv_polygon = self.ob.data.polygons[f_index]

    vertices = []
    # export the triangle
    for i in range(3):
        vertices.append([self.ob.data.vertices[uv_polygon.vertices[i]],
                        self.ob.data.uv[uv_polygon.vertices[i]]])
    try:
        Face(vertices, uv_polygon.material_index)
    except:
        Face(vertices, -1)

The error appears here: self.ob.data.uv[ uv_polygon.vertices[i] ]
because uv is not an attribute of mesh.
Thanks

The Blender OpenGL Exporter Addon has the code necessary to do this.  http://ksolek.fm.interiowo.pl/Blender/

UV coordinates are stored in ob.data.uv_layers.active.data[loop_index].uv since the mesh system update (NGons are supported from 2.63 on). Note that a loop index is required, not a vertex index.
UV textures are stored in ob.data.uv_textures.active.data[face_index].image.
http://www.blender.org/api/blender_python_api_2_73_release/info_gotcha.html#ngons-and-tessellation-faces
You might wanna use the tessface mesh (triangles and quads) for your export. Don't forget to triangulate quads, your original code doesn't seem to handle them at all. Here's an example:
https://code.google.com/p/blender-cod/source/browse/blender_26/export_xmodel.py#518

(About the quad it is handled in the full code)
Is loop_index equivalent to uv_polygon.vertices[i] in my code ?

Every face used to have 3 or 4 vertices, and the uv data was stored on face-level (fixed-size array of 4 elements, each storing a pair of UV coordinates). Since the amount of vertices per face is now unbounded, it's no longer stored there. It's rather stored per-face vertex (=loop). You can get all loop UV pairs like: [ob.data.uv_layers.active.data[li].uv for face in ob.data.polygons for li in face.loop_indices]. Note that .tessface_uv_textures has an interface like the old mesh system (no loops, stored on face-level).

I'm nosure to understand this notation, I'm not advanced in python (as I need the list of uv corresponding to the vertices I listed)
About tessface_uv_textures I first updated my old code using that but I had no data, like if it's not getting material...

I found the solution, for thus who will look for, as I'm getting vertice indices with uv_polygon.vertices[i] the uv indices are gotten with uv_polygon.loop_indices[i] which gives self.ob.data.uv_layers.active.data[ uv_polygon.loop_indices[i] ].uv to get the uv's.


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Wrong texture unrwap when combining two textured objects with boolean union
sorry for bothering, but I'm having a slight problem with using the union feature in the boolean modifier. I'm currently creating a wooden bridge that is made out of several textured planks. My goal was to create this bridge in a .blend file, and then append it into another file where all my final objects were combined. Whin I did this, I saw that I would have to append all the single planks from the file. I used the boolean union to combine the planks into one mesh, since this would make it easier to handle. But when the objects were in union, the unwrapped faces of one of the objects would deform and get randomly placed somewhere in the material of the other object. This would stretch out and show the wrong part of the texture at the wrong face.
tl;dr: Textures from different objects get messed up using boolean union, what other ways can I combine objects?
Does anyone know how to solve this? is there some other way to combine the items without ruining the texture? The mesh is also kinda complicated, and mapping the faces and creating the texture would be inconvenient AFTER combining all the objects.


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Heightmap on top with flat sides?
I have a plane with a Displace modifier, as well as Subdivision. I've imported a heightmap and got it to the desired height, however I'd like to make this into a solid block.

Essentially I want to bring the edges straight down, with totally flat sides and bottom. I've tried a few things such as extrusion, solidify and thickness, but neither worked as intended (possibly a conflict with the subdivision).
This looked like what I wanted, but it still doesn't provide the results I'm looking for.
If I simply extrude the outer edges down, this is the result:
https://gfycat.com/charmingbarealbino

have you tried to assign the extruded part to a vertex group, as suggested in the link you provide, or here by Marty Fouts?

Make a cube

In Edit Mode

select the vertices of the top face of the cube.
Create a new Vertex Group
Assign those vertices to the new Group
Add your Displacement Modifier
Set it to use your new Vertex Group

I simply used the landscape generator to generate a landscape, tabbed into edit mode, selected the bottom faces and extruded it down the Z axis
Maybe you need to apply your modifiers before extruding or apply all transformations.


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How to select objects and join them with Python
My problem is that I have a scene with many objects , which are grouped into EMPTY, I need to take all of the objects in the parent (EMPTY) and unite them into a single object , if you do it manually, it takes a lot of time

Can't you just select them all and hit Ctrl+J in Object Mode?

Yes I can, but it will take a very long time , about an hour for one scene , such scenes have a lot of

I work in the project company , and we are developing a 3D model of the plant , import the model into a blender , and ultimately have a huge number of objects and groups , only about 10,000 teams and 600,000 objects

Here's the pseudo code:
make sure nothing is selected to start off.

for every empty that has children:
    1. select all children of the empty
    2. set first child to active_object (or any child)
    3. invoke a bpy.ops.join
    4. deselect everything

Because you can't join anything to an Empty, You have to programmatically set a Mesh Object to be the Active Object then join other selected mesh objects to it.
Here's the python:
import bpy

# get the list of empties that have children
empties = [e for e in bpy.data.objects if e.type == 'EMPTY' and e.children]

# we need to deselect everything first
bpy.ops.object.select_all(action='DESELECT')

for empty in empties:
    for obj in empty.children:
        obj.select = True
    joiner = empty.children[0]
    bpy.context.scene.objects.active = joiner
    bpy.ops.object.join()

    # deselect everything before the next iteration
    bpy.ops.object.select_all(action='DESELECT')


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What is best workflow for having a scene with multiple light setups?
I have a scene with interior room design and I created several light setups for it (daylight from windows, powerful electric light from the ceiling, moody evening light from floor lamps). What would be the best workflow to work with that and be able to batch render them?
For now I have each group of lights in different layers. I can then select which layers I want and start rendering. However this doesn't allow me to batch render several setups at once, because there is no command-line to switch layers on/off.
I read about scenes and wondered if making several scenes which would have same objects, but different lights would do. Batch rendering is possible. But I'm afraid that working further on the design, adding new objects etc. will be tricky, as I will have to somehow synchronize all objects between these scenes.
How is this normally achieved?
I need still images only, no animations.

UPD: if you aren't familiar with scripts, I can provide non-script way.
For example, I have 2 light setups on 2 layers:

Now I'm going to animate visibility of lights, I will have first light setup visible on frame 1, second — on frame 2.
I'm setting 1 frame, and in outliner setting invisible and unrenderable objects from all light setups except first. In my case it is lamp:

Next I'm adding keyframes for visibility and rendering  for all lights in all light setups including first. To add a keyframe you must move cursor on icon and press I, icon will be highlighted:

Next i'm going to frame 2 and doing same procedure for second light setup.

Setting end frame in render properties and enabling all scene layers

In the end I'm checking light visibility by moving from frame to frame.   Now I can render object in 2 light setups by rendering animation with 2 frames.

I ended up using Render Layers, however I will try to use this method (animation) to render multiple images from multiple cameras, which I also need to do. It looks like this will work for it. Thanks for help.


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Blender hangs for a minute
My blender hangs very often for a minute on two. Sometimes it doesn't, in 90% cases it does. Typical places where it hangs are:

at startup, just after showing console window, before showing UI.
at file -> Open, before showing file / folders UI
at File -> Export -> FBX - before showing UI, it hangs while the menus is still visible

This makes it really annoying to work with. What could be the reason for the problem? I tried disconnecting the network, because I thought the network drives might confuse it, but this didn't change anything. My files are all on local drives.
I run on Windows 64-bit, hardware is a decent laptop with 16 GB RAM, but it seems the problem happens when nothing is really going on, what would require gears.
The console doesn't print anything new in these cases.

This happens for me on Windows 10 when using a non admin account. I couldn't find a solution yet.

@stacker  It happens to me on my Win10 Surface3 tablet, even with the admin account.

If I had to guess, from your description I would say it is Blender trying to access some unreachable location. Such behaviour seems to be connected to disk reading activity, like when opening or browsing for a file or location.
I've had a similar problem a while ago when I had a faulty DVD drive installed. I later came to find out that disconnecting it made blender behave again.
Is your hard drive health poor, or is it very full?
Check if some other program is reading or writing heavily to the disk, or if you have a optical disk drive installed that may be causing access delays.
Are you connected to a network? If so check if you have any configured network drives or remote places Blender might be trying to access.
Try disconnecting all that and see if the delays still happens.

@Arek said, "I tried disconnecting the network, because I thought the network drives might confuse it, but this didn't change anything."

@dedwarmo: I did disconnect network before entirely, not network drives. This did not help.

I verified it has sth to do with network drives. If "My Computer" is opening instantly, Blender starts fine. But if it's showing a progress bar for a minute trying to figure out network states, so does start Blender. Is there any workaround other than removing network shares? I have some number of them, need them for work, and they point to locations which are only sometimes available (while on VPN or when some virtual machine is running)

Ok got it and posted as another answer.

I marked the first correct answer as accepted. This is indeed a problem with network drives. But it seems I found a workaround, so I post it here.
The workaround removes all network drives from Blender, so it doesn't hang while trying to access them. It will also kill the possibility to save / load files to network drives in Blender. I do not need this feature so this is fine for me.
Before you start with this, try running Blender as Administrator (right click on its shortcut and choose 'Run as administrator'. I heard it might remove network drives on some systems. It did not work for me however. Verify by going to File> Open in Blender and see if network drives are still there.
Steps which resolved this for me:

Create a new user in Windows. I named it "Blender". Set administrative rights to it so it can access all the files and create a valid, strong password for it so nobody will login to the PC with it.
Create a shortcut somewhere (ie. desktop) to start blender. It can be a copy of the blender shortcut which is in the start menu (Start -> find blender -> right click -> copy, then right click on desktop -> paste).
Change the target of this shortcut, so it is not:
C:\Program Files\Blender Foundation\Blender\blender.exe
but instead:
runas.exe /savecred /user:Blender "C:\Program Files\Blender Foundation\Blender\blender.exe"
If your path to blender.exe is different, adjust accordingly. If you username is different than Blender, also change it.
Now double clicking new shortcut will start Blender on this different user account. At first run it will ask for the password - enter the password set for the Blender user.
Blender will start instantly, because this new user doesn't have any network drives mapped.
If caring for look, you can change the icon for the shortcut, because now it doesn't look like anything Blender like. Just find 'Change Icon' button in shortcut properties, navigate to:
C:\Program Files\Blender Foundation\Blender\blender.exe
and set a proper icon.
Blender is now like fresh install without user settings. You can copy your current settings by copying:
C:\Users\\AppData\Roaming\Blender Foundation\Blender\2.76\config\userpref.blend
to
C:\Users\Blender\AppData\Roaming\Blender Foundation\Blender\2.76\config\userpref.blend
This path might different on your system or different Blender version. Do the same with other files in this folder: 'bookmarks.txt' and 'recent-files.txt'. If you have more files there, consider them as well (I only had those).

Nice workaround, thanks for the explanation

Excellent answer, thanks for contributing to the community!

Duarte Farrajota Ramos is right with his answer. I find a similar behaviour when I had some network drives mapped at work, after only using standby came home where those aren't available any more and I want to open anything in Blender that uses a File Browser. It seems to wait for some timeouts. Disconnecting all network drives usually disables these time lags for me.
This has already been reported as a Bug, but has been archived and is now a ToDo:

Add timeout to file browser, so network which is hicking up does not annoy artists

Good to hear it is on the roadmap. Is there any workaround other than removing network shares? I have some number of them, need them for work, and they point to locations which are only sometimes available (while on VPN or when some virtual machine is running)

I think, adding this mentioned timeout would be a workaround only and the real problem is based in Windows so that Blender only get's some notification pretty late after some network timeouts and is just innocently waiting for them until being able to display or use the complete drive list.

Ok got it and posted as another answer.

I had a similar problem, and it turned out that, while I had no mapped network drives I still had some inaccessible network locations pinned in the Windows "Quick Access" menu. Here's a page from Microsoft on how to remove such items. After that, Blender starts in 5 seconds! yay!


text:
Is there a way to batch render images from several cameras?
There is one scene, but several cameras and I would like to render this over night to have one image per camera (no animation). Is this possible? I don't see a command-line switch to select which camera to render.
I'm using cycles render, if this matters.

Simplest way (even without command line): https://blender.stackexchange.com/questions/3502/how-can-i-make-a-camera-the-active-one/3503#3503

Do you mean the method with markers?

OK I will take a look at this, I didn't use any animations and frames so far so something new to learn...

I used this method and it works great!

Probably the simplest way is to use Multi-View cameras as described in this answer. All that is required is to enable ‘Views’ in the Render Layer properties and configure one view per camera with a particular suffix. Set your cameras with the same name and matching suffixes - so, for example, you could have suffixes of ‘_L’, ‘_R’ and ‘_T’ for left, right and top, and name your cameras Camera_L, Camera_R and Camera_T.
When rendering you will now get an image produced for each view. Each inage file produced will bear the relevant suffix - eg, ‘0000_L.png’, ‘0000_R.png’, etc.

I actually hacked together an addon that allows you to do this (windows compatibility only and only Blender 2.8 tested). Once installed it adds a panel to the Output Properties tab with a button for rendering all stills and a button for rendering all animations.
https://github.com/astonfuture/render-all-cameras-blender-addon


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Shading / smoothing - how does it work with edges, faces, vertices?
There are options in edit mode in Shading/UV to mark faces, edges and vertices smooth or sharp / flat, but I don't understand how do they work and can't find it anywhere in internet. I understand basics and I see difference between smooth / sharp edge. But how are those three (edges / faces / verts) related?
I see I can make a face smooth and this changes the look in Blender, but it doesn't make the edges around this face smooth. Are these unrelated? How does it work then? What is a difference between marking all edges of the mesh smooth, or marking all the faces smooth? What is the point of having all edges around the edge sharp, and the face itself smooth? Or the other way around?
Then there are also vertices which can be smooth or flat, but this seems to be related to edges. It looks like it just changes all edges connected to this vertex to sharp / smooth. Is this correct?
It would be great if someone could explain it a bit.

I think smoothing is an operation on edges only.
https://www.blender.org/manual/modeling/meshes/smoothing.html

This article mixes edges and faces, which confuses me even more.

If you have a cube and you set everything to render as smooth, then the faces of the cube will be shaded as though the object were a sphere. You can still clearly see that it's a cube since that's obvious from the geometry of the mesh, but the shading will try to behave as best it can as though the cube was actually smoothed say using the subdivision modifier.
Now take a cylinder. If you create a standard cylinder then you can clearly see that it's not perfecly round, that the sides are made of 32 faces. In order to make this appear perfectly round you could increase the resolution of your mesh, which would lead to worse performance and longer render times, or you could just change the shading to smooth. Now if you change the shading to smooth for the whole cylinder then the shading will again try to make the cylinder look as though everything was smoothed, that's good for the sides, but it's not what you want for the caps, since you still want the cylinder to clearly be seen as such. That's when you'd need to go and change the shading of individual faces of your mesh in order to maximise the appearence. Go to edit mode, select only the top and bottom faces (the caps) and mark them as flat. Exit edit mode and you'll see the cylinder displayed perfectly, smooth on the sides, but flat on the caps.

Ok, but this is somthing I understand, as stated in question. What I don't understand is how edge smoothing relates to face smoothing. I can make all faces of the cylinder smooth and all edges sharp. Or I can make the opposite. What is a difference between smoothing faces and edges?

if you smooth a face (quad) you're smoothing 4 edges/ 4 vertices...

So basically, it's a question of how deep/detailed you want to go. If setting this for the object as a whole is enough for what you want, then you don't need to go into edit mode. If as in the example of the cylinder, you need different settings for some faces, then you can set that on a per face level in edit mode. From there you can go deeper with edges and vertices if you need to smoothing the be more specific....

Well I wanted to control smoothing on my mesh entirely. The shape is more complicated than a cylinder and it has some faces, which should be smooth on some edges, and not on others.

According to "if you smooth a face (quad) you're smoothing 4 edges/ 4 vertices" - it seems not correct to me. I create a cube in Blender, select all faces in 'edit mode' and set them to smooth. They change the look. Then I select all edges and make them sharp. They become blue colored, but the faces remain smooth. I can then select any face and switch it between smooth / flat and see changes in the look of it, but the edges remain blue / sharp.

So basically you're saying that you need to control smoothing on the level of edges or even vertices. Well, you can do that, just select the edges that should be smooth and make them smooth, then select the edges that should be flat and make them flat...

what you say is true. I didn't realise that the options in shading/uvs are not the same for faces and edges. Setting something to sharp is not the same thing as setting something to be rendered flat. I was going to suggest you try the edge split modifier next, and it's related to marking edges as sharp. with it you can choose to display as flat the edges that are marked as sharp. It can also automatically set edges to flat/smooth depending on the angles, which can be quite a time saver.

I tried Edge Split modifier, but while it did a good work in some cases, it didn't do anything in other cases. In some cases where it works, it gives good results which I can't achieve by manually setting edges / faces to smooth. If it doesn't provide good results, I can't fix it because I don't understand the basics - hence this question.


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How to get a pose bones rotation (custom exporter)
Well after weeks of searching online and nothing found I decided to ask online. I want to get the x, y and z rotation of a pose bone or even just a bone. I can't seem to get it working I have a rough understanding of matrices and would really like it if I could figure this out. So please guys help me get the x y and z rotation of a pose bone/bone (I am writing a custom armature exporter)

Welcome Jp Silver :) These answers might help: http://blender.stackexchange.com/questions/3618/global-pose-rotation-of-a-bone/5438#5438, http://blender.stackexchange.com/questions/1283/how-to-get-world-space-matrix-of-any-pose-bone Please start with the tour: http://blender.stackexchange.com/tour Anyway, enjoy blender.SE!


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Particle system: How to place random objects with children?
I'm trying to place a group of trees that include an armature and leaves in a separate mesh scattered over a land. The problem is that only the tree's base is placed by the particle system, even though the leaves are a direct child of the base (see screenshot):

The first 3 trees in the middle are placed manually, the other ones are being placed by a particle system, as you can see, without leaves.
I found this answer, but it uses 'whole group' to tie objects together. The problem I then have is that I can't create a 'list' of trees to place at random. I wanted to comment on said answer instead of making my own question but I didn't have enough reputation to do so.
What would be the best way to use the particle system to place random objects such that I can still use objects with children? Thanks!
Other reasons for using Particle System:

I can use a mask to distribute trees manually (like this guy)

Please state your experience with Python.  How many trees are being placed?  Are they relatively static?

This is a known [situation] with particles.  Python can address this or systems which use Python.  Children are not necessarily copied with particles or animated. Yet you could coordinate animated groups via Python to use the location and rotation and size et cetera of Particles.

If you are in the favorable position of having a few trees and need immediate results I would place them manually. (No Particles) I have placed animated objects using Particle information. Yet we still need to know your Python experience. Also you might want to state if you want a pre made solution ... or you want to learn something by building your own solution with Python or tools using Python.  Lastly there are tools that do crowd animation ... where your trees could be the crowd ... you may want to search for such add ons.  I have not used them and cannot remember the names at this time.

@atomicbezierslinger my Python experience is highly proficient, are you suggesting I'll try using Python? (I was thinking about it, but hoped for a more integrated solution)

@atomicbezierslinger there aren't many trees to be placed but it's nice to know how it works in case I do need to place more of them, also I like it better when placed at random rather than doing it myself, as somehow the results seem more favorable.

Many people have seen this deficiency in the past.  Particles do not seem to copy hierarchies.  I have used Python or something like Python [?] to deal with this.  Yet I still had to manage copying a heirarchy which seems to be best documented and observable by Blender duplicate mechanism.  So my goal in the past was a little Python exploration and getting results.  The duplicated items in my past example were animated with a particular style.  I was willing to pay programming time for that style.  Please state how much animation your trees exhibit.

My current belief is the addon may serve your needs. If searched and found, you would become that expert because I did not use the add one.  Blender Particles system is not intended for highly animated where each particle has some independent organic movement.  So if you can find that addon or another addon that is a reasonable approach.   Particle systems with visual dust have less scrutiny than tree swaying in the wind perhaps.  You may not be using  some features of particles such as collision.  My comments above about using some readable attributes of the particles system are still valid.

@atomicbezierslinger they currently just have an armature. I didn't start on animations yet, I wanted to experiment with a slight wind.
I was thinking of making a python script that "replaces" dummy particles (i.e cubes) with a full copy of said tree (with children). I think that might be the best way to solve this, especially since there doesn't seem to be an integrated way to do this.


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Blender cycles won't render halo particles
I am an inexperienced user of blender, and created a scene of a manikin using blender  2.69 and rendered it using cycles  to produce a .png image which I was very happy with. I wanted to progress further and incorporate the use of Halo particles with this scene, but discovered that cycles will not render halo particles. (I looked at the 'dupli'  option but this won't give the same effect as a BI halo particle when rendered).
Question 1 - will the new version of blender  - v 2.74  using Cycles render halo particles or do I have to retreat to Blender Internal - BI (Blender render).
Assuming it probably won't, I opened my blender file and attempted to render my scene using blender Internal.  The result was  a complete blacked out manikin and only a white floor visible.
Question 2.  Am I going to have to start all over again, because I need to use the halo features of BI and using cycles seemed to have put me up a blind alley, or is there something on my current file that I could change/focus on so I can get it to render (and therefore use the halo features) with BI.

You could render just the particles in BI and composite them over your cycles render via separate scenes. See http://blender.stackexchange.com/q/1756/599

That's because you're coming from cycles and all your materials are cycles node materials.. either delete them and create BI materials or click on the little nodes icon right from the "x" in the material panel...

Since the Gooseberry Branch we have Halos in Cycles with the Point Density Texture. So you don't need to start from Scratch.

Hi Samoth, thanks for your comment, clearly I need to upgrade to the latest blender version! but I'm currently head down in a java/android project, so won't be able to try out your suggestions for a bit, but hopefully this will save me huge amounts of time when I get back to this :-) .


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How to make the Image Input node process every file in a sequence of OpenEXR or OpenEXR Multilayer .exr files?
My setup  i5 2500K processor @ 3.3 GHz  and 24GB ram.  Using Blender  v2.79b
I have rendered out a set of 11 frames  in  OpenEXR and  OpenEXR Multilayer format. Each  set is produced from rendering a 3 layer blender file.
Using an image node, set to image sequence  (as below)  these 11 files are connected to a composite node with the output set to produce .png files.

In both file types, the image node only processes the first file and produces blank files for the other 10, with the multilayer file format producing pink output .png files and the Open EXR files being black .png files.
I've read elsewhere that the pink colour is produced because there's no image there. I've  picked up the images  individually one by one in the image node, and it displays the image content of the file perfectly.
Why can't the image node process every file in the image sequence using the Animation button?
Can I have some help on this, I have an animation of 530 frames to composite and doing them one by one  rather wastes my processor!

Mixing standart EXR + multilayer EXR in one sequence is a deadend. If you need additional passes besides Z-depth then stick with multilayer for whole animation.

Sorry I think you misunderstood what I've being doing, I'm not mixing them, I just tried each type as I couldn't get either one of them to work, and I'm not using any passes, just trying to get  from .exr to a .png

Can you share a stripped file? No need to attach textures, you can even replace your objects with simple cubes, just leave renderlayer setup untouched.

Not sure what you mean here,  need a bit of guidance,  is the 'stripped file'  one of my rendered .exr types, or are you speaking of my starting blender file?

Whole .blend file you are working with to https://blend-exchange.giantcowfilms.com

I'm trying to strip the file down, but having problems reducing the size and being able to replicate the render & layer settings I've got in my original  blend file - this may take some time!

Well I've  simplified  things down to the minimum, still using my original render settings, it’s a 530 frame fly round. The blend file  'Stripped down test file.blend' was used to create 11 .png frames with a transparent background. I then fed them into 'REC-Composite-take1.blend'  as an image sequence in the node editor compositor window, and attempted to put a yellow background on all 11 .png frames.

Needless to say it failed and only produced one frame with  the yellow background from the  first frame in the sequence, thereafter all frames were just yellow.  So try it for yourself!
I think there must be a bug. I didn't bother trying any .exr files, as if it can't manage .png  there's not much point trying .exr!  I look forward to your results/comments!
only problem here I can't get the giantcow thing to work at all,  so not sure if you'll ever get to see the files above!!

If your file is too big, then upload to any filehosting you can

I may have cocked this up completely but  view this question and it may have the links to my uploaded files   https://blender.stackexchange.com/questions/123314/broadly-how-to-combine-pre-rendered-images-in-openexr-or-openexr-multilayer-for


text:
Extrude seems broken
Just starting out, created a planar mesh, in edit mode, hit E to extrude, and I get this:

Extrude doesn't create any perpendicular faces or vertices, it just duplicates the flat mesh and grabs it. What's going on here?

I think you might have hit Extrude once, and not moved the mouse and now there are duplicates of every vertex. You can remove doubles and Extrude again, should work fine.
This is what you're seeing:

Select everything, press W -> Remove doubles. Then try to extrude again:
This is what you want to see

There were no duplicate vertices, but I realized what was happening when I viewed face normals- somehow I had a duplicate face on the other side (the entire n-gon).

As you've only started out using Blender it may be difficult to track down the exact steps that introduced this confusing result (hitting F joins selected faces, i suspect that was involved too).


text:
How to swap the active image bake for multiple objects
I'm currently working on a model in blender I plan on baking the ambient occlusion normal maps and textures. But for each map I want to bake I have to manually select each part of the mesh and change it to the desired image to bake onto. Is there any way I can assign an image to all of them at once without having to manually swap them?

I guess that you use Blender Cycles engine. In this case, I think this is not possible. Cycles baking is done into image which must be present in the node tree for each material. There is Bake Tool addon which probably speeds up this behaviour, it's paid though. So by default you add image texture node for each material, you can Ctrl+C > Ctrl+V them.

I was using blender render.


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How to fix non-manifold boundaries
I am new to 3d modeling, and I have some problems after finishing my project. To preface, my goal was to create a tiger mask.
My problem is that when I show my non-manifold elements, I have some non-contiguous and boundaries non-manifold, shown below:

As I said, I am new to 3d modeling, but I did notice that the boundaries ones were shown where there was a hole or opening, as in the eyes, mouth, or back. Why would this be? I could find nothing that would cause the non-contiguous ones as well.

Related - http://blender.stackexchange.com/questions/7910/what-is-non-manifold-geometry. Loops which are disconnected from other geometry even if have connections to parts of mesh (like those selected on your mesh) are also treated as non-manifold. If you add some thickness to your mask, the mesh will be treated as manifold. You can use Solidify modifier for that.

If the mesh is not closed, that is one type of non-manifold geometry. Adding a Solidify Modifier is one solution, if you're concerned about it. In real life too, a mask could not be infinitely thin.

Thank you, this seems to have fixed my boundaries, but I still have quite a lot of non contiguous. What could these be caused by and should I worry about them?

I realize you have long since figured it out, but this is one of the top Google hits for when I was trying to find out.  Non-contiguous means that some of the normals are facing this way and some are facing that way.  Recalculate your normals, and if you have a good mesh, it should work itself out.

For me, the usual cause for non-manifold surface due to boundaries is disconnected or doubled edges/vertices. Inspect the edge to see if there is something underneath or if you have a degenerate (0-area) hole in the mesh (e.g. 3 vertices in a line creating 3 edges resembling a flat triangle instead of the two valid edges etc.). Merge by distance is quite useful in this case, sometimes after some helper cuts through the faces.
Similarly, you usually get non-contiguous due to flipped or otherwise broken normals on only part of the mesh. They are detected as non-manifold because a transition from a valid to flipped normal creates a manifold boundary. Mesh -> Normals -> Recalculate (probably outside for anything other than interiors/rooms etc.), and it should be fixed.


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how to show all layers with hotkey (emulate numpad enabled)
How can I show all layers with a hotkey? ~ key does not work. (correkt key according to blender wiki) https://en.wikibooks.org/wiki/Blender_3D:_HotKeys/3D_View/Object_Mode
 - Because (I have sensei format and a swedish keyboard).
I want to quickly be able to view a background image only, hiding all objects, in use when sculpting to see my ref image for one second. - this is possible with show all layers hotkey, and so how can i find or change the hotkey for show all layers in the user pref? Thanks.

The ` key (tilde) should work with Emulate Numpad activated. It might have been remapped to something else, refer to the answer by @sambler for relevant details.
There are several other ways to work out this problem:
Use the Local View on some empty object

Local view isolates the selected object or objects, so that they are the only ones visible in the viewport.

Local View

Add an emtpy from Shift+A > Empty.
With it selected, press Numpad Slash on the keyboard (if Emulate Numpad is used, / button is accessible for that).

The viewport will enter Local View for the empty object; as it is small and doesn't reflect any geometry it won't mess around in the scene. The background reference image will be available for fast and easy previewing.
Note:

you can also use any object from the scene for that; select it and enter Local View.
this way is accessible from the keyboard, however you should have some dummy object for it to work.

Use background image settings
Background images can be set up to be visible behind the scene objects or in front of them.

Front / Back
Choose whether the image is shown behind all objects, or in front of everything.

Note:

in order image to fully cover the objects the Opacity setting should be increased to 1 (or something higher than default).

this setting is inaccessible from the shortcut; you'll need to use Background Images rollout a lot from the Properties shelf.

First check that you aren't in local view as this disables the 3Dview layers. When in local view you won't see the layer buttons in the 3Dview header and if you have the view name at the top of the viewport you will see (local) there.
You can find the shortcut settings in the Input Preferences, if you enter layers into the search box you will see a list of actions involving layers with the shortcut keys, clicking the key will allow you to change the shortcut used and then you can click Save User Settings to enable that shortcut each time you start blender.

The default key for "show all layers" on a Swedish keyboard is Ö.


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How can I project text around a sphere using shrinkwrap modifier?

 text object doesn't project correctly to my mesh sphere, and often (but not always) blender crashes when I try "Mode project".
I can't get the text to wrap correctly around the mesh.
So, why doesn't "project mode" Do anything? (except crashing blender) - When i am able to apply it, nothing happens.

Thanks in advance, / Dan

Please edit your question and provide more info. It's not clear what you are asking. Show us some screenshots and reference images of what you are trying to achieve

ok, updated... does that make more sense? =) can you help me fix the problem? - i still didn't solve this. thanks..

Curve objects alone don't work well with the shrinkwrap modifier, it can only project correctly the border vertex, but since the "text fill" has no subdivisions it has no geometry, so can't  be projected as expected. You will probably have to finish your text object first, then convert to mesh, subdivide it manually, and only then shrinkwrap. If blender crashes you should report a bug with the file attached.

Check this Blend file:
For the Shwinkwrap modifier to generate a smooth result in a situation like this, more geometry is needed. You need to subdivide the Text Object first to provide the necessary detail. Luckily, this can be done dynamically using modifiers:
Setup a Subsurf Modifier on the Text object. Set its mode to Simple instead of Catmull-Clark to avoid distorting your Text object. Subdivide as many times as needed, but try to stay on the lower end (I chose 2 for Display and render):

Now, to use Projected as a mode, you'll need to setup the Axis correctly as well as which direction Blender is supposed to look for the other object to wrap on: I chose my sphere as a Target, then set the Axis using the check boxes (note that for the modifier the LOCAL Axis of the object counts. In the first screenshot you can see that the blue arrow correlates with the direction I want to go in, so that's the Z direction). The direction field now lets you choose the direction in which Blender looks for the Sphere. Again, look at the first screenshot: the Blue Arrow points AWAY from the sphere. That means, to make the Text wrap towards it, the Direction needs to be set to 'negative'.


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nurbs curve not bending mesh correctly
on this car tire model, the nurbs curve is not bending the mesh (surface of intended car tire) correctly:
It is obvious what I mean by looking at this screenshot, and feel free to inspect my blend file:  https://app.box.com/s/s7vi3l06lf9vv6ir9j5ysfz9t0v9qhka

what i want is the mesh perfectly (smoothly) aligning, bending exactly right together at each end. I've been trying for hours to manipulare the nurbs curve, and since i'm a newbie to blender, still don't know how to fix the curve just right.
Any tips?
Cheers / Dan

You just need to reset the object rotation values for the nurbs curve so that it is exactly 90 degrees on the X and Z axis. Then it will line up correctly.


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why grid lines + scale doesn't update, when controlled via python console?
I can successfully controll the grid_scale & grid_lines in bpy.types.SpaceView3D.
I know this, because the console tells me that my input has been recieved, for example, when I write: bpy.types.SpaceView3D.grid_lines
the console prints my new value.
But here's my question: Why doesn't the values update in the Blender Properties panel, I mean visually in my current scene? (check my print screen you can see the values haven't changed. - that's the problem.)
I'm new to scripting so a simplified answer would be brilliant.
Thanks / Dan

Difference between a class and an instance.
bpy.types.SpaceView3D is a class, it has a grid_lines property. The blender UI has a window, made up of screens, made up of areas, within each area an active space (what you see in that area). The active space in a view 3d area is an instance of the bpy.types.SpaceView3D class.
Running this code in the text editor will change all 3d view spaces grid lines to 10 and scale to 2
import bpy

for screen in bpy.data.screens:
    for area in screen.areas:
        if area.type == 'VIEW_3D':
            area.spaces.active.overlay.grid_lines = 10
            area.spaces.active.overlay.grid_scale = 2

in the python console the active space is not a 3d view area, rather a python console.  Similar to above but in console
>>> type(C.space_data)
<class 'bpy.types.SpaceConsole'>

>>> for i, a in enumerate(C.screen.areas):
...     i, a.type
...
(0, 'INFO')
(1, 'PROPERTIES')
(2, 'CONSOLE')
(3, 'VIEW_3D')
(4, 'TEXT_EDITOR')

>>> space3d = C.screen.areas[3].spaces.active
>>> type(space3d)
<class 'bpy.types.SpaceView3D'>

>>> space3d.overlay.grid_lines = 10

If the code is invoked, via a button or menu (for example),  in the context of the 3d view, then the 3D VIEW space would also be context.space_data

Brilliant answer! You made me understand what's going on, and thanks for your help, & for the perfect clarity!


text:
How to do seperate render passes in blender?
I a lot of VFX breakdown that uses something they call "render passes". From what I see, they are rendering the clip in seperate ways (like rendering the ambient occlusion, specular, shadows, depth of field, etc individually and then combine it). Is there any way I can do this?

Of course. But it really depends on the shot, your render engine and particularly on your further compositing/math workflow/skills whether this makes sense to do at all. For the most cases this is huge overhead, but if you really need full control about image color values this answer could help implementing a workflow.

Actually, your question is a little bit vague, you have everything you need to begin to understand this topic on the Blender Reference Manual
Short answer, because this is a huge topic, and your question implies that the concept itself isn't quite clear for you (the reason I advised you to first read the manual ;) ), but the concept is to :

activate the needed passes in the render layers section

use nodes to separate the different passes

This opens a lot of possibilities, because you can independently tweak every passes, export each ones to different locations, if you have just one parameter to modify, it doesn't need to re-render everything, etc...


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How many objects touch one chosen object?
I am making a simulation using Blender physics. I pour many objects in cube-shaped box. I need amount of objects which touch one particular object. I know one way: at first I return location of each vertex of each object and then for one object I compare its vertices coordinates to possible touching object's vertices. If distance between two vertices is less than constant number (that constant depends on distance between two neighbor vertices of one mesh) this means that this is touch point. Then I count this touch points. But this algorithm needs lot operation ((amount of objects)(amount of vertices on each object)(amount of possible neighbors)) and lot time to be completed. I wonder if there is any script or option in Blender which returns how many other objects touch each object. P.S. Perhaps it is possible if we add collision sensor from Game Engine but I don't need this.

Does this help: http://blender.stackexchange.com/questions/9073/how-to-check-if-two-meshes-intersect-in-python ?

Yes it helped me to find out that there is no way in Bullet physics engine to directly test for collisions

as @stacker said the answere was in How to check if two meshes intersect in python?
this the "new" code in order to answer your question:
note:  the "chosen object" must be the active object.. I mean the last selected object... check:

import bpy
import bmesh

def bmesh_copy_from_object(obj, transform=True, triangulate=True, apply_modifiers=False):
    """
    Returns a transformed, triangulated copy of the mesh
    """

    assert(obj.type == 'MESH')

    if apply_modifiers and obj.modifiers:
        me = obj.to_mesh(bpy.context.scene, True, 'PREVIEW', calc_tessface=False)
        bm = bmesh.new()
        bm.from_mesh(me)
        bpy.data.meshes.remove(me)
    else:
        me = obj.data
        if obj.mode == 'EDIT':
            bm_orig = bmesh.from_edit_mesh(me)
            bm = bm_orig.copy()
        else:
            bm = bmesh.new()
            bm.from_mesh(me)

    # Remove custom data layers to save memory
    for elem in (bm.faces, bm.edges, bm.verts, bm.loops):
        for layers_name in dir(elem.layers):
            if not layers_name.startswith("_"):
                layers = getattr(elem.layers, layers_name)
                for layer_name, layer in layers.items():
                    layers.remove(layer)

    if transform:
        bm.transform(obj.matrix_world)

    if triangulate:
        bmesh.ops.triangulate(bm, faces=bm.faces)

    return bm

def bmesh_check_intersect_objects(obj, obj2):
    """
    Check if any faces intersect with the other object

    returns a boolean
    """
    assert(obj != obj2)

    # Triangulate
    bm = bmesh_copy_from_object(obj, transform=True, triangulate=True)
    bm2 = bmesh_copy_from_object(obj2, transform=True, triangulate=True)

    # If bm has more edges, use bm2 instead for looping over its edges
    # (so we cast less rays from the simpler object to the more complex object)
    if len(bm.edges) > len(bm2.edges):
        bm2, bm = bm, bm2

    # Create a real mesh (lame!)
    scene = bpy.context.scene
    me_tmp = bpy.data.meshes.new(name="~temp~")
    bm2.to_mesh(me_tmp)
    bm2.free()
    obj_tmp = bpy.data.objects.new(name=me_tmp.name, object_data=me_tmp)
    scene.objects.link(obj_tmp)
    scene.update()
    ray_cast = obj_tmp.ray_cast

    intersect = False

    EPS_NORMAL = 0.000001
    EPS_CENTER = 0.01  # should always be bigger

    #for ed in me_tmp.edges:
    for ed in bm.edges:
        v1, v2 = ed.verts

        # setup the edge with an offset
        co_1 = v1.co.copy()
        co_2 = v2.co.copy()
        co_mid = (co_1 + co_2) * 0.5
        no_mid = (v1.normal + v2.normal).normalized() * EPS_NORMAL
        co_1 = co_1.lerp(co_mid, EPS_CENTER) + no_mid
        co_2 = co_2.lerp(co_mid, EPS_CENTER) + no_mid

        co, no, index = ray_cast(co_1, co_2)
        if index != -1:
            intersect = True
            break

    scene.objects.unlink(obj_tmp)
    bpy.data.objects.remove(obj_tmp)
    bpy.data.meshes.remove(me_tmp)

    scene.update()

    return intersect

obj = bpy.context.active_object
contador = 0
for sub_obj in bpy.context.selected_objects:
    if sub_obj == obj:
        print("is the same active object")
    else:
        obj2 = sub_obj
        intersect = bmesh_check_intersect_objects(obj, obj2)
        print("There are%s intersections." % ("" if intersect else " NO"))
        if intersect:
            contador +=1

print("How many objects touch one chosen object?: " + str(contador))


text:
Export rigid body location without baking to keyframes
I'm making simulation in blender for rigid body. I need object location in the current frame. I use following command
bpy.context.scene.frame_set(250)
bpy.data.objects['Object'].location

but this command returns the location corresponding to the initial frame.
Neither changes object location in Location panel during simulation. I know I can bake rigid body transformations to keyframes but I need another way to get location of object because baking takes long time for multiple objects. Is there any other command which can print object location after transformation without baking?

Yes, Location/Rotation/etc. returns the values visible in relevant fields of the object transform in the UI, kind of 'initial' transformation. To get final one, you can use:
bpy.context.scene.frame_set(250)
bpy.data.objects['Object'].matrix_world.translation

Note that:

This gives you absolute position of the object (world space), if you want its relative position (to parent e.g., local space), you'll have to use matrix_local.
You should bake physics simulation before using frame_set().

Thanks so much. I actually used this to export a model after doing physics simulations for.


text:
Bending a railway line
I'm entirely new to Blender and am learning as I go, so I need a bit of step-by-step guidance please.
I'm working on some voxel based graphics, creating them in MagicaVoxel, exporting as .obj files and then importing into Blender. Most of the graphics are easy enough, however I have a railway line which looks like this:

In this case I want to 'bend' the railway line to become a curve, I need to make a number of curved sections in this way. I want to use these as 'tiles' within a game design environment (Unity) and so the rail needs to stay flat to the 'ground' of course and I want the straight and the curves to fit together, like pieces from a model railway would.
I've looked at some online videos and so on and ended up playing with the Simple Deform - Bend modifier, but I can't get to grips with it at all, the results I'm getting are nothing like my expectation!
Can anyone please provide me with some advice to help me understand how to approach this? Any guidance would be gratefully received. Thanks.

I'd recommend using an array modifier and a curve modifier. See my answer here: http://blender.stackexchange.com/a/2867/599

a lattice could also do the trick.

Bithur - Can you provide any pointers on that?

basic (but good) tutorial on lattice from blenderDiplom : https://www.youtube.com/watch?v=x_kcXMzASds

@gandalf3 Using a curve modifier has the disadvantage that in general the railroad ties will not be square anymore after bending the object along a curve.

@maddin45 This can be worked around by arraying a plane object, then using duplifaces to put ties on each face of the plane (http://blender.stackexchange.com/q/5910/599). However with reasonable curves (for a railroad) the distortion on the ties is quite subtle to begin with.

curving a mesh will result in...a curved mesh! if tou want the wood part to keep rectangular, you'll have to separate them.

My inexperience with Blender is proving to make working through these suggestions rather slow work for me, I haven't managed to achieve what I'm looking for as yet. I appreciate your help so far everyone. If anyone is able to put up a video of how to do this I might find that a better way to understand what to do. I'm finding that Blender is a rather overwhelming tool for a newcomer to 3D editing work.

First apply an array modifier to the train tracks. With a distance set to one, this will make the rail segments touch, and iterate. Then, add a bezier curve. Select it, press tab to switch into edit mode, and then manipulate it to get a good shape. Apply a curve modifier to the rail, and set the object to be the bezier curve you created. The rail will curve to match your bezier curve. An invaluable resource in blender is the modifier encyclopedia on Andrew Price's website. Great tool for reference. Hope this helps!

I didn't manage to follow these steps completely; when I get to the point where you say 'Apply a curve modifier to the rail, and set the object to be the bezier curve you created' Blender says 'Modifiers cannot be applied in Edit mode' - what does this mean?


text:
UV mapping - Comes in reverse and then mis-wraps to other parts of the bottle
I tried to uv map a liquor label onto a bottle and it comes in reverse.. fine... so to compensate I reverse the png file so it's shown correctly.. however now the label shows up on the side of bottle too.. which of course was NOT part of the UV faces I selected. Any ideas how to fix please?
The png label and blend file are here:  http://www.aworkofmarc.com/1/blender/teeling

It's not necessary to rotate the image so to map it on the model in different ways. You can select adjacent UV map island as it's reverted, press S > Y > -1 to invert it by Y axis.

The label shows across all the bottle because this UV map consists not only from front UV island. There are others for all the parts of the bottle, so the image is mapped on those parts too. I'd recommend using masking - paint on the model parts where label should be and use it as a Factor input

Can you direct me to where or how I do "masking - paint on the model parts where label should be and use it as a Factor input"  Sorry I'm so painfully new / inept.

Related - http://blender.stackexchange.com/questions/19039/how-do-you-overlay-an-image-on-a-shader-in-cycles. The only thing you are left to do is to create a mask (black - no image shown, white where image should be seen)

Also related - http://blender.stackexchange.com/questions/7476/cycles-compositor-apply-color-balance-node-only-on-a-part-of-image


text:
Blender 2.75 to 2.76 When adding an object I can't find the tool menu now!? Add (Vertices / Depth etc)
Please see picture.. When I add an object there used to bne a place where i could adjust it before clicking off of it -- now that menu has gone somewhere and I can't find it. Am I missing something, I didn't turn on?

Click the + icon at the bottom of the region.
When the redo menu is resized to nothing, it is hidden and the + button for re-showing it appears:


text:
Forcing Blender to measure ONLY in inches (not feet)
I have Blender set to Imperial but I want to work ONLY in inches. So for example, 13 inches to show as 13" and NOT 1.1'  and 72" to show as 72" and NOT 6'
Is that possible?

I believe if you check the separate units check box that should give you what you at least the thing displayed in feet and inches(rather than decimal notation).  But I don't know if it possible to have it only show in inches as noted in your example.

That's better... I guess.. Thanks. But still it would REALLY be best if I could get it to show ONLY inches.  Is there an addon out there that might do it? I searched a bit but didn't find one.


text:
Rendering ruins the scene with drastic object displacement and stretching
As the screen shot shows when I render this scene the objects were completely displaced and the label stretch as compared the window render. Any ideas as to what's causing this?

Probably some modifiers were setup so to affect only on rendered image, not on viewport preview. The same with the plane - it could be hidden in the viewport, but nor in render.

If Mr. Zak's comments don't solve it for you, post the blend file.

I stripped the modifiers and it corrected the scene. Thank you.

Related - Why is part of my model not being rendered; also - Object not visible in render (in your case it's viceversa)


text:
Is it possible to have a Material input node in the Cycles Renderer?
The Blender Render(er) has the so called "Material Input Node", where a previously defined material can be selected. The questions is, whether there is an equavalent for the Cycles Render(er).

No. However you can do something sortof like this with renderlayers, see http://blender.stackexchange.com/q/2612/599

What would you use it for? Node groups can help both in linking materials or creating an interface where you can plug in maps...

It may help you to note that Mix Shaders and Add Shaders are the two types of nodes that can actually combine other shaders. So if what you're trying to combine can't be handled by one of those two combination methods then you need to tackle it at the color level, using MixRGB nodes and such.

I think the ubershader would be the closest to the old material node.

@Carlo In BI you can use the result of one material in the nodes of another material, which allows you to do things like this.

Thanks for the link @gandalf3. I never thought of that usage: BI will always have its say! I'm with you, a perfect equivalent cannot exist. Were you (the questioner) looking for getting the material result?

All the given answers in the comments work correctly and as I expected.
I finally ended up using the Node Groups.


text:
Boxes not colliding with each other
I want two boxes two collide with each other but they don't. I have triangulated the faces and the rigidbody has dynamic and active on. Keyframes have been set with the end keyframes ending up with the boxes at the same location.

Is this for the game engine? Do you have a blend file you can post?

@AnthonyForwood It is tagged [tag:rigid-body-simulation].

@Shady Puck - I have no idea what that means.

@AnthonyForwood It's like the game engine, but a lot simpler. It's what Scratch is to Python (coding languages) or Cycles (Blender) to Renderman (Pixar). See BlenderGuru's awesome beginner tutorial called Quick Rigid Body Fun.

What????? I mean I don't know what tagging means or what telling me that has to do with anything.

I thought I did. So much excess stuff on websites in general that I can't be bothered to read every little thing or spend a lot of time searching for what is claimed to be there. Not my fault. Important things need to be more distinct./

From the information given, it seems you are trying to use dynamic rigid bodies with keyframes, but haven't set them up to allow the animation system to take over the simulation. There is a difference between the two setups, so I will leave a basic example of of how this can be done:
First the difference between the two:
Dynamic rigid bodies-
strictly controlled by physics:

Animated rigid bodies-
controlled by the animation system until you change this!:

Here's how to set it up:
1. Add a rigid body simulation. Active, and dynamic, and select
    animated. Also, use the collision margin, and set this fairly high. The limit is 1. Do this for both objects. You can also play with the mass options if you like. Also, apply transforms with Ctrl+A>rotation & scale

2. Insert a location keyframe at frame 1 for each object with I>location.
3. Select and add a keyframe to the animated checkbox in the physics panel at the same
    frame the simulation will begin by hovering over the checkbox and pressing I.
4. Set your end keyframe for the collision of your objects, and again choose location, or what whatever is applicable to your needs.
5. At the frame following the collsion uncheck the animated
    option in the rigid body options for each object, and set a new
    keyframe.
From this you should be able to expand and make many interesting simulations from colliding cubes to anything else.