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Convert annotations to Grease Pencil object (old GP to new GP)
I'm playing with the new version of Blender (Beta 2.8) and was wondering how I could open/import old Grease Pencil animations (done before the 2.8), which are now called annotations if I understood correctly - and load them into the new Blender as Grease Pencil objects ?
Thanks

In Blender 2.8, use F3 - Convert To Grease Pencil which will convert annotation to a GP , select the newly created GP then edit its material (stroke/color) in the properties panel for it to be visible

I finally found out and it's quite easy:

In object mode, show the right sidebar of the window by clicking n.
In the Annotations section, check which is the name of your (old) Grease Pencil datablock. For ease of reading, rename it OLD_GP.

Create an empty Grease Pencil object (SHIFT+A > Grease Pencil > Blank)
In the properties panel of that object, go to the Grease Pencil tab.
Load the datablock that we have previously renamed OLD_GP.

Now we need to assign a material to the Grease Pencil because it it currently "invisible" :

Go to the materials tab and click New.

Et voilà !

You can now remove the datablock from the annotations.

Looks like it is not working anymore as of 2.8 2019/04/08


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shortcut to show a single channel (solo mode) in the graph editor ?
Does anyone knows if there is a shortcut to show only a single channel in the graph editor ? (eg. key + click)
I always have to uncheck all channels but one to work... And that's quite annoying.
Thanks !

You can select the channel and press Shift+H to "Hide Unselected Curves". This option is also found in the Channel> Hide Unselected Curves menu in the graph editor.
You can then press Alt+H to "Reveal Curves" to bring the hidden ones back.

source: Stack Exchange

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

sort: votes


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2.8 - Is it possible to assign (override) a material to a whole collection?
I have a collection that contains linked assets.
I would like to override their materials and give them a unique material.
Is it possible to assign a material to a whole collection, and how ?
Thanks !

but if you append the assets - updated geometry isn't reflected in the linked files... so a override option is urgently needed

If your model consists of only one object you can link the mesh/object data rather than the whole object, then create a new object in the scene and set the mesh/object data to the linked one.
You can then add any material you want (as only the mesh is linked) and any changes done to the original mesh will still be made to the linked one.
Note however that modifiers will not be linked this way and you will have to re-add them yourself.
Edit : Here is a clear answer with pictures :
1 - Create your model

2- Notice the name of the object data :

3- Duplicate the object using Alt-D to maintain the same object data (as shown) :

4- Go to material settings for each object and change material link to object instead of data (data is the default option).
You can also do this step before duplicating if the number of objects is big :

Now you can assign different material to each object :

Any changes applied to the mesh will affect all objects but each will have its own material :

Notice that modifiers are object specific and if you change the modifier settings of one object it won't reflect on the duplicates (only mesh changes are shared) :

Hello and welcome to the site! As of now your answer is quite hard to follow. Could you add some screenshots or menu directions so it's easier to understand?

What i found is:
Mark the whole Collection, press CTRL+L, select Material and select the material you want.
That will Link the selected material to the whole selection.
source

Yes ! Working ! But what I would love is to be able to set a material to the collection (an object would keep its own materials but it would be overriden by the collection material).

The only way to do this is to change the materials in the original file(s).
The whole purpose of linking is to have one source in eventually multiple projects. Change the source and all the projects get updated, that have links to that source.
In your case, the collection should be the source and other projects should create links to this collection. If you do it the opposite direction, the collection doesn't make much sense.

Okay, but what if I have a collection of assets I reuse often in a file, with each assets having several materials assigned... But that for a specific project, I don't need materials, just a unique one / clay / whatever ?  How would you handle this ?

@gordie - you would append the asset to that specific project. Appending creates a "local" copy in the new file, that can be modified.

The idea is to have kind of a clay material for the whole scene...

@gordie - where's the problem with that? You just assign that clay material to every object. Can even be done in one step.

in each file then, not in the scene containing my linked objects ?

The whole point of overrides is that one can override the data.  This is why they are called overrides.

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


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problem projecting a photo onto a mesh
I want to animate a quick shot of a road (photo) where my camera moves slightly.
So I'm trying to project a photo on a mesh on a simple "tunnel".
I've read this topic, Project photo onto mesh UV texture, and I've built a scene setup using Fspy.
Once in Blender, it seems that everything is correct; my mesh does match the picture.

But once I unwrap my mesh, it doesn't work at all as expected :

Project is here if you want to have a look at the file.
What am I doing wrong ?
Thanks for your help.

are normals inside? (control+shift+N to switch normal "inside")

How did you unwrap? Make sure you are looking through the camera and select U -> Project from view.

Hello :). The perspective seem to be a little extreme, perhaps CGMatter can help :)

This is due to the extreme perspective that forces high errors on simple geometry as mentioned by @jachymmichal.
One way is to add geometry to your cube before projecting UVs from view. Here is a way using the subdiv modifier:

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


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Making a shader that would "fill" an open mesh?
I made a material that mixes two shaders using an empty which acts like a kind of mask for those shaders.
If I move my empty up, there will be more blue shader.
If I move it down, there will be more transparent shader.
My goal here is to make a glass that would be filled with water; using a single mesh with this special material, and moving my empty to "fill" the glass.

It is working quite well, but...
As the material goes along the mesh, it shows up like if the mesh missed a face; has its "cap not filled".
I was wondering if it was possible to tweak my blue shader so the mesh would always seems closed ?

Thanks !

related http://blender.stackexchange.com/questions/5113/how-to-make-one-object-gradually-disappear-as-it-passes-through-another-object

Staying inside Cycles alone might not produce the desired results..

Here i'm using the Z component of the Geometry's position socket to compare with a scalar value (Representing the distance from the ground)

Most likely you'll need to animate a boolean intersection with a plane, one slice of will be the glass/transparent material, the other slice will be the solid/diffuse material (or whatever you want).
Here i've separated them spatially to indicate they this method uses two X Objects to and two planes, both planes point in opposite directions:

The closest I get without making it complicated is this:

It uses the Normal of the upper cut to decide how much to mix between glass and transparent. The normals pointing downwards (on the cutting surface) are the faces that are mixed to Transparent most. The exact shader mixing is something you'll need to decide on yourself.

for a proper fill effect you might have to make a shrunk version of the X (offset inwards), and only animate that with the boolean intersection / plane. The outer regular X shell would then stay static.

Ok, thanks for your reply ! I was wondering if it was possible without using booleans but apparently no.  Thanks !

You didn't mention wanting to avoid the Booleans in your question, it might be possible.. but the creation of that extra set of internal faces to resemble the liquid surface will still need to be done with a real mesh I think..  Wait around for a better answer

related: http://blender.stackexchange.com/questions/8600/how-can-i-easily-animate-cutaway-views-on-multiple-objects

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


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Procedural modeling of complex shape
What is the best/easiest way to model something this:
Preferably procedural.
Also I need it to be rectangular in the finished result.
(I know it could be done afterwards with a boolean modifier but let's say I don't want to have to use this as a last resort)

Modeling this by hand would be extremely time consuming and I'm positive this could be done using mainly procedural methods like modifiers.

You sould try out the sverchok addon or animation nodes. Jimmy Gunawan has recently posted a video on how to acheive a similar result on youtube https://www.youtube.com/watch?v=M2QVSoN_51c

Do you need real geometry or is procedural volumetric material ok?

@Jimmy: Nice addon, I'll surely check this one out.

@Jerryno: Yes, I need real geometry. but this does not have to consist of one single mesh. As long as it's not obvious for the viewer.

@zeffii Here is a link to a very similar model
https://www.harolds.nl/images/producten/groot/prod__1382972819_groene-boomkruin1-650.jpg


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Particle emitter is intersecting bounding boxfaces
I am trying to configure a mesh as a bounding box to generate particles completely inside a given mesh without sticking through the 'bounding' faces.
As an example: the left cube has a volume emitter with objects sticking through the faces.
I would like the particle objects to NOT intersect the bounding mesh. (also in case of more complex objects)
The preferred method I'd like to know would result in a box with no objects intersecting it's faces what so ever.(right cube)

You might be interested in this answer: http://blender.stackexchange.com/a/68389/28015

I'm not so much worried about self intersecting as much as the emitter geometry sticking through the bounded box or custom object.


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Importing .fbx results in triangulation
What causes a Quad mesh to be triangulated when importing it in blender and how can I avoid it?
(note: the .fbx export was done in 3ds Max with correct settings)

In the export dialog, not only uncheck Triangulate but also Preserve edge orientation. This option is here to avoid issue on non-quads i think.

Unchecking Preserve edge orientation did the trick.
Thanks!


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How can I set the maximum draw type for multiple objects?
I'm currently working on a scene containing 1000+ objects which all need to be set to a different draw type to save on computationally expenses in the viewport. But doing this for every object separately is really tedious.
Therefor I'm wondering if there's a way to change the maximum draw type of multiple objects simultaneously. Preferably only the selected objects.

Just right click on the "maximum draw type" list and choose the "copy to selected" option:

Note: this function is available in many contexts (not all).
Additional information:
As said Duarte Farrajota Ramos in the comments, you can use the Alt key whilst clicking on/choosing the wanted 'maximum draw type'. And that will apply it to all selected objects without using the menu indicated above.
But this Alt key won't work here if you have the 'Emulate 3 Buttons Mouse' in the user preferences (which allows to use the alt key to replace the middle button features, if you are using a track pad for instance).

Thank you for your clear answer! I totally forgot about this feature.
I now have my scene optimized in a couple of seconds instead of the expected hours!

You can also keep Alt key pressed while changing values to apply to all selection

@DuarteFarrajotaRamos, you're right. Just for information, if you have 'emulate 3 buttons mouse' in your settings (as I have) this will not work (as 'alt' is unavailable because of that).

Didn't know that,never used Emulate 3 Buttons Mouse feature myself, but nice to know. Maybe add those to your answer as well.


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How to convert a cycles material node setup to a python material generation script?
Is there a way to convert a cycles material node setup to a python script which in it's turn can generate a new material with the same node setup?
Also, is it possible to somehow retain the x,y postion of these nodes for easy readability?

Yep, that's possible. Hardest part is finding a way of holding the data (used nodes, their connections etc.) in any reliable way IMHO.

You can probably create a node_group programmatically and then instantiate the group.
Do you know what the setup looks like in advance? I suggest you load a node_group from a template Blender scene.
Here is an example of how I append nodes from external Blender scenes, I personally like this approach a lot, you can find the source files here:
def import_material_node_groups():
    """ Load the archilogic cycles material node groups from the node-library.blend file.
    """
    filepath = os.path.join(os.path.dirname(os.path.realpath(__file__)), 'resources/node-library.blend')

    with bpy.data.libraries.load(filepath) as (data_from, data_to):
        data_to.node_groups = data_from.node_groups

    for node_group in data_to.node_groups:
        log.debug('Importing material node group: %s', node_group.name)
        node_group.use_fake_user = True

# Material group node (The datablock is not yet assigned)
node_group = node_tree.nodes.new('ShaderNodeGroup')
node_group.location = (0, 0)
node_group.node_tree = D.node_groups['group-name']

Alternatively you can programmatically create a node group (see this question, and then instantiate it like shown above.
Each node comes with a location data, so you can save your node locations with "location" or you can programmatically order your nodes if you know what they should look like.


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How to render an environment only pass?
I'm having trouble rendering an environment only pass.
The problem I'm having is that objects in the scene will cause the environment pass to include blacked out regions where they're positioned.
Is there a way of having the environment pass rendered completely without objects masking out certain regions?

@cegaton it works, I'm wondering what passes I can uncheck to boost render times though. I've unchecked everything and excluded all scene layers. I've only checked the environment lighting pass and 'use environment' (render sky in this layer). Am I forgetting something?

@cegaton If you can put your comment as an answer I'll mark it as accepted. Thanks!


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Is there an easy way to see what is consuming the most memory?
Is there an easy way to see what is consuming the most memory?
For example:
-Objects / Object data
-Textures
-Lighting
-Particle Systems
-Material duplicates
-Caches
-Anything else that can cause unnecessary memory consumption...
I'm trying to cut down on memory consumption in a very large scene that would otherwise take ages to do manually.

Perhaps: http://blender.stackexchange.com/questions/3183/troubleshooting-blenders-memory-use-memory-statistics

@JamesThomas This doesn't seem to do anything. Broken feature?

It works for me.  Start it in the command line ("cmd" in windows) navigate to Blender's folder. perhaps "cd \Program Files\Blender Foundation\Blender" then "blender --debug-memory" then in Blender, open the file you want to test.  Then open the spacebar menu, run "Memory Statistics" and change the window back to the console to see the detailed memory statistics.  If you have problems, try googling some, and if you still have issues, detail what you did and see here so we can help.

http://www.lifehack.org/articles/technology/20-tips-use-google-search-efficiently.html In case this helps.  I knew almost nothing about this till I searched.


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How does blender really save a blendfile?
While working on a blendfile that is approximately 1GB and consists of many different objects, groups, materials, particle systems, etc.
When saving your file, does blender overwrite the entire 1GB blendfile or does it simply add, change or subtract certain data to the repository?

Information about file format here in github https://github.com/dfelinto/blender/blob/master/doc/blender_file_format/mystery_of_the_blend.html

According to the Blender wiki provided by lemon:

Saving and loading complex scenes in Blender is done within seconds. Blender achieves this by saving data in memory to disk without any transformations or translations. Blender only adds file-block-headers to this data.
A file-block-header contains clues on how to interpret the data. After the data, all internally Blender structures are stored. These structures act as blue-prints when Blender loads the file.

If I read this correctly, it means that blender just performs something like a memory dump and writes that to a file and just adds some meta data to it. This is a quick way to write big chunks of data to the harddrive, but makes for a though job when re-loading the .blend file.
This is because during load you must check for changes in platform, blender version,... as described in the wiki article as well.
All in all I think the answer to you question is yes: Blender does indeed write the full 1GB file to your harddrive. It is a lot faster than writing (for instance) a 1GB Word document because blender just 'dumps' the data rather than exporting it in a document format that is fairly easy to interpret on reload.


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How to select objects based on texture data?
Is there a way to select all objects in a scene that are using a certain texture?
Without differatiating materials, linked or appended data, lost database connection and so on.
For example:
I import a scene with a lot of different objects.
Some of them are using the same texture but on different materials.
I'd like to select all the object that are making use of this texture, even if they are located in different materials or lost their connection to the library (linked/appended materials).
Note: Not sure if what I'm asking for is eligable as one question. Just hoping that there is a simple solution for selecting objects based on texture data.

In theory Select Linked via Shift+L in Object mode is designed to do that. However I know it to work like you describe only in BI; it didn't do anything in Cycles (as it uses node-based material and thus texture is a node).

In the outliner editor window, at the right hand side of the menu bar, where the default item in the selection window is "all scenes", activate the drop down menu by pressing the arrows at the right side of the button, and select the menu item "data blocks". In the data blocks list, find "textures", and click on the plus-sign-in-a-circle to the left of the entry, and click on that to expand it. This will show all textures in the scene, and allow you to select them, or if not, to at least determine which objects in the scene are using the texture.


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How to resolve the Z pass when rendering with subframes?
Currently I'm trying to render my scenes by making use of subframes to save on rendertimes through rendering on multiple nodes.
But when I do this I'm having problems combining the chuncks from the Z pass.
As you can see in the combined image below the Z pass does not show correctly.
It seems to reset the nearest and farest point of each individual subframe.
How should I go about fixing this? I'm all out of ideas.
 Any help would be greatly appreciated!
Combined Z pass chuncks:

Example of the python script I'm using:
cat >subframe.py <<EOF
import bpy
bpy.context.scene.render.border_min_x = $SF_MIN_X
bpy.context.scene.render.border_max_x = $SF_MAX_X
bpy.context.scene.render.border_min_y = $SF_MIN_Y
bpy.context.scene.render.border_max_y = $SF_MAX_Y
bpy.context.scene.render.use_border = True

def add_subframe_to_fo_path(scene):
    scene.node_tree.nodes['File Output'].base_path = '$OUTDIR'
    for file_slot in scene.node_tree.nodes['File Output'].file_slots:
        file_slot.path=file_slot.path + '_X-' + str($SF_MIN_X) + '-' + str($SF_MAX_X) + '-Y-' + str($SF_MIN_Y) + '-' + str($SF_MAX_Y)

bpy.app.handlers.render_pre.append(add_subframe_to_fo_path)
EOF
blender -b *.blend -P subframe.py -F PNG -o $OUTDIR/frame_######_X-$SF_MIN_X-$SF_MAX_X-Y-$SF_MIN_Y-$SF_MAX_Y -s $START -e $END -j $STEP -t 0 -a

Node setup:

Hardware/software specifications:
Blender version nr:  2.78a
Render engine: Cycles
OS: Linux Ubuntu

@cegaton I'm normalizing because I want to use the output image as a custom mist effect to overlay on my renderlayers. and also to use as a lens blur alpha in photoshop. Leaving out the normalize node seems to resolve the issue I'm having. But now however I'm not able to stitch the EXRs

Your Normalize Node is scaling the values so they range from minimum to maximum for each part individually. Leave it out and you should be fine. You could use a custom normalization scaling that is predefined and does not depend on the maximum and minimum of one subframe, or scale the Zpass of the whole image after merging.


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Compound rigid body in cycles
I would like to create a compound rigid body. I had a look at this video, therein compound bodies were created by sampling primitive bodies together. The collision shape was set to a primitive like box or capsule. Than these bodies were all parented an so connected to each other and acted as a complex body.
However, the video used the blender-game mode, where the physics panel looked different to the one available in cycles-mode. In opposite to the video there is no option to set the collision bounds to compound.
But probably some images to explain:
That hook is the a hierarchy of 9 cylinders, each is a rigid body.

That is how it looks like in the outline:

This is the view of the physics panel:

Finally I connected each body with another, using »fixed« as constraint type, but all in all, the resulting body is not stiff and deforms, what is not what I want. I would like to have a completely stiff body. How can I gain that?

Could you provide your .blend as a starting point? What you are looking for should be possible.

You'll probably have to increase the number constraint solver iterations in Scene > rigid body world. That said, you might be better off using the Triangle mesh collision shape on a normal hook model. Also note that this feature was written as part of the 2013 Gsoc, but doesn't seem to be integrated yet..

You can also use Override Iterations and increase the number of iterations in the constraint panel for the constraints.

give it a shot…

This is not possible in official blender at the moment, however this feature was written as part of the 2013 GSOC.
I haven't seen word of it since, so if someone knows why it hasn't been integrated with master yet, please tell me :P
The closest you can get is the Mesh collision shape:

I don't know if this is an option for you, but you could Join the meshes (Ctrl-J) into a single mesh, eliminating the need for Fixed constraints.
If that is not an option, then increasing the number of iterations as suggested by gandalf3 and user2859 is probably the best way to work around the wiggle inherent in the Bullet physics engine.


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Linked Objects, Drivers and Animation of custom Properties
I have created an Object with some Shape Keys. To simplify the planned Animation, I have created four custom Properties on that object and connected some drivers, so that the change of one Property effects multiple values of the Key Shapes.
That does all work as expected is seems to be pretty nice! But I would like to use that object in an Animation where it should appear two times. So I created a new Blender File and linked that object two times and made a proxy out of each.
In Summary: One File, containing two proxies, linking to one Object in another file.
When I try to animate these properties, It happens that no matter which of both I select, all the key frames are created for the second object I have linked. Except for one Property.
In Curve Editor (Animation View), the curves to edit are always the ones of the Object that is not selected.
Am I facing an error here, or do I have anything missed? Is it possible to do what I would like to, or can't that be done with linking?
Any Help appreciated! Thanks in ahead!

I'm facing the same issue. Did you manage to find the issue? And it even gets messier with three or more proxies. Blender never seems to find the right target.

It seems like this is not supported yet in blender. to bring in the same object multiple times you need to save the object again as another copy and import that separately...
people have answered this here:
multiple copys of character with rig linked in the same file


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Chandelier with physics
I would like to model a shape which is enclosed like such a chandelier, so that I can apply some wind force to make it move.

The basic structure of the enclosing, cloth like material should somehow look like that:

I have had a look at lot of tutorials showing how to make String/Noodles, but there are two things I do not really know how to do:
1.:  How to attach a rigid Disk on a string, or chain of vertices
2.:  How to create this whole lot of string with this whole lot of disks attached?
I appreciate any help, since I do not have any Idea how to do that. If coding is necessary, its no problem, I fine with it, since coding is what I normally do!
Thanks in Ahead!

You were probably searching for the wrong keywords for your tutorial, you may want to search for "Physics Chain" instead.
This one seems to put you in the right direction.
Anyway you will have to model your chain of links in some sort of rest pose, using the Physics tab in the 3D view Toolbar set all chain objects to Add Active except for the ends of the chains or any fixed objects they will attached to, which should be set to Add Passive instead.
For all of them make sure you change the Collision shape to Mesh under the Properties window > Physics Tab > Rigid Body Collisions Panel > Shape and the Source to Final if they are using any sort of modifiers.
Also set the Mass and Margin properties to a low value under the Rigid Body and Rigid Body Dynamics panels, like 0.001 depending on the dimensions your objects.

You will almost likely need to increase the precision steps of the simulation  to a higher value under Properties window > Scene Tab > Rigid Body World Panel > Steps per second. Probably a high value like 1200 or higher.
Also for simplicity sake if you have repeating parts in your lamp like equal chain strings you may want to make a group out of them and clone the group instance instead, so Blender will only calculate physics for one instance. Although if you plan to make it react to physics this will not work.

When using rigid body physics you need to make sure you work in dimensions larger than 1 cm, or the objects will act chaotic.

This looks really good! Gonna check it out tomorrow morning!

I have tried following each step, but the objects are just »exploding« so I guess they are too small… What should the smallest length be? In this case the diameter of one of the rings? Do I have to work in a metric/unit bound system, or can I also use no unit?

Well in metric units those are quite big and out of scale, actually, each of the larger circles is probably around 2 m diameter. You might have to model it intentionally big and scale it down after baking. I had a lot of exploding problems too, you'll have to tweak values a lot. I had to increase the simulation steps a lot, otherwise objects fell through each other, and reduce the mass and gap of all objects a lot too. Don't forget about the mesh settings for modifiers I mentioned

I don't know what is wrong with my tries… Can be anything from geometry to proportions to settings… Do you think you could post the .blend file from above anywhere, so that I could compare? I would really appreciate that, since It took me a whole day to delay the explosion of the chain to frame 100.

I'm afraid I lost the original file, not sure I ever saved it in the first place. I uploaded a similar one, download link in the answer above


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If I'm using hair particles for grass using groups, how can I create dead spots?
By dead spots I mean places where grass won't grow on my plane e.g. for walkways. I've been wondering this for a while but I haven't seen anything in regards to it online. Thanks!

Possible duplicate: http://blender.stackexchange.com/q/6250/599

@TLousky you gave a link to the same answer gandalf3 suggested as a duplicate :).

Hah! Silly me, deleted it.

Yeah turns out I wasn't using the correct words when searching. Hard to search when you aren't aware of the lingo! Thanks for the help and sorry for the duplicate post!


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How would I make these curved indents in this water bottle? Picture in description.
I'm relatively new. I know how to make a water bottle starting with a circle and extruding upwards while using a combo of extrude and scaling to make indents, but how would I do something like this? I'm still trying to wrap my head around some of the photos I see out there. This is such an incredible program. Thanks for your help!

I know how to do this, I should have time to post an answer tonight a little later

Start by making the main outline of your bottle. Once you have that, hover over the section you want to add the inset to and press Ctrl+R. Use the scroll wheel to select exactly how many you want.

Now use Ctrl+Tab+E to switch to edge select mode. Holding Alt+Shift, right click on the newly added loop-cuts. Press Ctrl+B to bevel and roll the scroll wheel one click to add another loop cut in the middle.

Now select the inner loop-cut on each of those rings. Now press Ctrl+. (period) to change to the Individual Origins pivot point. Scale the selection down as desired.

Now go into orthographic mode, and press Numpad 1 and select the center vertices as shown. Move them up as desired. Go ahead and press Numpad 3 and do the same thing. Enable a Subdivision Modifier, and bevel the edges using Ctrl+B.

Final result:

If something is unclear, let me know

Wow I didn't think I would get an answer thank you SO much. Really. This community is really easing the initial learning curve of this program. This technique is going to help me in many occasions.

I am actually having a problem. I have selected the middle loop cuts, but when I press control+period nothing happens.

Acutally I figured it out. You press and CTRL+. and then you scale it.


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when i press "p" it doesnt play my game
I am making a game in blender and when I press p to test my game, the screen goes white and when I press escape it goes back to normal and I don't know if my game is working or not.

switch to tectured veiw

Possible duplicate: http://blender.stackexchange.com/q/34116/599


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Saving painted version of model
For some reason, when I go to 'Texture paint' and paint my model, it doesn't keep those changes when I get back to the normal object stuff, and I didn't observe much, but sometimes it even doesn't save my painted texture so I have to start all over again, anyone please help?

And how can I do it?

All these instructions are weird and confusing.

@KapKing What exactly is confusing? What have you tried so far?

I tried the UV Mode thing, tried ways to find the textures to be able to right click them and find 'Save' and tons of other methods I can't remember :/ but now it seems to have saved :D

Now I noticed, it keeps the changes from texture painting, but doesn't export the texture :/


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How do I make the .mtl file contain a color for every coordinate
My .mtl file looks like
Blender MTL File: 'None'
Material Count: 1
newmtl Torso1Mtl
Ns 1000.000000
Ka 0.000000 0.000000 0.000000
Kd 0.800000 0.000000 0.000000
Ks 0.200000 0.000000 0.000000
Ni 1.000000
d 1.000000
illum 2
map_Kd Torso1Tex.png
map_Ka Torso1Tex.png
map_d Torso1Tex.png
so when I try to import an .obj file with .mtl file into Roblox Studio and this is the reason the object isn't colored.

Sorry I forgot to finish my sentence. So I want to know, what can I do to make it contain a color for every coordinate, just like the title says.

Seems like you'll find your answer here:
http://gamedev.stackexchange.com/questions/21303/how-can-i-include-vertex-color-information-in-obj-files

Thanks but, it has to be .obj and .mtl to be able to convert it into Roblox, and the 2nd option, I think he said make the .obj file itself have the color data, which is bad, since I need them to be seperate, also I don't have much experience other than Lua :/


text:
Rendering smoke and volume object which is emitting light causes black spots
I'm creating animation with shooting gun.
I've created gun model, smoke emitter which is placed at the end of the barrel and muzzle flash - volume shader with emission.
Everything looks fine until the smoke starts to flow out the barrel cause you can see 'muzzle flash' which looks like big black spot inside, even when volume density is 0.000.
Another problem is that smoke also affects muzzle flash when volume density is 1.000 there are transparent deformations which causes holes in flashing object.
It looks like smoke is ruining everything in my animation. Because without this effect everything looks really cool.
I've tried to separate gun, smoke and flash. I can easily render each of those but rendered together causes same problem (gun with smoke - good, gun with flash - good, flash with smoke - bad, gun with flash and smoke - big fail) .
Image:

I still don't know how to fix this. Maybe it's just a bug and that's why I'm asking: Do you know how to solve this problem or maybe just how to separate layers? And why smoke and emission (even if it should be 'transparent') affects each other so much?
By the way - I'm working with Blender Render.

It seems as if the transparent part of your material is not getting deep enough into the geometry. You should try adding a mix node with a transparent shader and see if it stops the cutoff of the smoke.

Simple transparent shader works well I mean that if alpha is set to 0 smoke looks good and shader too if alpha is set to 1 - the problem is that i can't use alpha in transparency options because I'm not using Surface (where it is possible) but Volume shading where density defines 'alpha' (not 100% sure) and volume density causes problems with smoke and shader itself (black spots). I mean everything would be fine if i use simple shader but muzzle flash looks better if it's volume. By the way - mixing nodes is only possible in cycles or maybe I don't know about something.

It looks like i've solved my problem. I've changed muzzle flash volume object that was appearing and disappearing - now it's a paricle emitter. Particle lifetime is just one frame so it looks pretty similar to previous effect. Smoke is not hidden anymore because there is no object that could do this - particle emitter surface is not visible and muzzle flash particle is there for very short time.
Strange thing is (which I've not expected when i was thinking about this solution)  that particle - which is an object with volume shader - is not bugging anymore! I mean there is no black deformations inside flash object even when all objects are on the same render-layer.
This funny trick fixed my problem but it will probably still exist if someone try to render smoke and volume object inside which is not moving or disappearing - black deformations on volume and hidden smoke when volume density is set at 0.000.

I hope this will help somebody.


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Project Image onto Cubemap
I am quite new to Blender and Textures, so this Question has probaly asked before... I have got a skybox and an Image and I would like to project that image onto that Skybox, so that it looks undestorted when looking through the camera onto that part on the Skybox.
On the Image below I have tried to line out what I would like to do

What I basically want is that the projection on the right looks as the Image on the left, from that very Point of view.
All in all I need the UV-Map, is there any "standard procedure" I could apply?
Thanks in Ahead!

Use Project from View option in the Unwrap menu (U).

To make texture appear on the mesh just like you see it in 3D View window unwrap the mesh using U > Project From View. From the wiki page:

Project from View option maps the face as seen through the view of the 3D window it was selected from. It is almost like you had x-ray vision or squashed the mesh flat as a pancake onto the UV map.

Note that because this option takes into account only parts of the mesh which are pointed to the viewer in 3D View, you

will get some stretching in areas where the model recedes away from you.

So use it when you know that you won't see areas in scene where faces of this mesh aren't pointed to camera.


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Create Outer Envelope of a Complex Object?
Given an complex shape that has unwanted inner structure inside the skin, I'd like to create an outer 'envelope' of the surface that ignores that internal structure. e.g. imagine a bunch of intersecting pipes, and wanting a solid that is just the outside surface, rather than the interior mess of walls at pipe-join spots.
So I'd hope to lose the non-manifold bits and end up with a sealed structure. On a simple shape I can do it manually, but on a complex one it would be prohibitively time consuming.
I've heard there's a shrink-wrap function somewhere, but I assume if you did a shrink-wrap of say a square bird-cage, you'd end up with a cube rather than the open space for the bird, which I'd also need.
Rgds
Ross.

If I understand correctly you'd like to model joint between 2 similar meshes. I don't think you can use shrinkwrap in case when you'd like to create a joint. Maybe related in case of pipes - http://blender.stackexchange.com/questions/42591/how-to-aproach-the-modeling-of-duct-work-piping-wiring. Another shapes may require another approach

Sounds like Boolean operations might be what you want, but hard to tell without more info. Also Boolean operations have very strict requirements and limited situations where they work well, so some care would have to be taken. Please edit your question and provide more details about your question, like some screenshots or if possible a Blender file.

Could you please add some screen captures so that we could understand a bit more how is the mesh you are talking about ?


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Seeking add-on for notes
I often wish there were an add-on to embed notes in a blender design, tacked to specific points in the model of an object. I mostly do 3D models for mechanical designs that get 3D printed, and sometimes for things that get built the old-fashioned way (cut, join, glue etc).
I would expect notes like that to behave like the "Grease Pencil" or "Ruler/Protractor" tools do now. Not physical objects, but like an info layer.
As a design evolves, many features have reasons for being as they are that may not be obvious so I need to make notes elsewhere, in a separate file.
"The flange needs to be 1cm wider near the bolt" or "Don't reduce the overlap to less than 1mm near the left side."
Those sort of spatial notes would be great embedded if I could attach them to the geometry directly, so I'd see visually why I did a thing, or changed something.
Also would be great for revisions - "previously tried at 1cm, need at least 2cm here."  This would reduce risk of repeating past mistakes.
Anyway - searched for such an add-on but haven't found anything. Anyone know of something like that?

Don't know of anything like that off hand. If you can't find anything, I'd be happy to quote on building it for you. You can contact me at todd@resonancemedia.ca.

You can use Grease pencil, created separately for object, with Stroke Placement option set to Surface. Then the text will be snapped to the mesh surface and it'll be seen only if that mesh is selected (if you haven't tried already).


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How to achieve a solid glass/emission material with certain refraction and color
I'm having trouble recreating this material in cycles:

It's a solid glass bulb with a LED inside and copper threaded fabric which gives it a copper colored glow.
I'm not sure how to achieve a similar hue / glow and IOR.
Any pointers into the right direction would be greatly appreciated!
Blendfile:

More reference images avaiable on:
http://bocci.ca/84-series/

One way to achieve it is what you already have setup, just mix a Glossy with an Emission Node and fake the effect perfectly. I could optionally ditch the Glass node if you don't need the transparency and want to simplify the setup.
If you want a more accurate and real material at the expense of more noise and don't mind the extra render time, then you can do it with actual translucency.
Mix a Glass and Translucent node and add an actual light source inside the map. This light source may be anything from an emission surface to an actual lamp.

You may also want to re-unwrap to improve you lamp UVMap so the texture is better distributed over the surface.


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Not able to delete certain materials from blendfile
I'm having trouble deleting certain materials from my blendfile.
In the example below you can see that the material appears to have multiple users while in fact there are no other objects in the scene that have this material assigned.

In the material browser the material shows as follow:
(however it should be called ''0 old Red Leather'' if no other users have this material assigned if I'm correct)

I've tried unhiding all objects, selecting linked materials by pressing SHIFT+L, saving and reopening the blendfile  but none of these methods seem to work.
What else could I do to delete these materials from the blendfile?

could you share the file through http://blend-exchange.giantcowfilms.com/ so we can check it?

@m.ardito I can't share the blendfile as it is subject to a NDA.

can you try duplicating the file, then on the copy delete all objects, then examine the material: it should become orphan, imho.

You should be able to press X button to the right of the materials dropdown while holding Shift key. It will remove any users of that datablock from the file and the 0 number will appear next to the material name.


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Bump map causes strange shading
What is causing this strange shading when adding bump/normal maps?
This happens in the viewport and the final render.
See image below were the sun transitions into shadow.
It should be more smooth.
Blender v2.79
Cycles
HDRI lighting

Bump map close-up:

Also, it seems that adding subdivions increases quality but at a great cost of performance.

Given the image, and the fact that subdivisions help, I'm inclined to say that it's a terminator problem.
Sadly, it's a common problem on most ray/pathtracers, so your solutions are:

Increase subdivisions.
Increase light sizes. This will make shadows softer, and will mask the problem a bit.
Use a non-tracer renderer (like Blender Internal or, maybe Eevee), that doesn't have this problem.


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How can I get shader node values based on object angle?
I'm trying to automatically change a blackbody's value based on a sunlamp's directional angle.
When the sunlamp shines horizontal, I would like to have a minimum value represented in the shader editor (minimum value = user defined).
When at it's utmost vertical position, I would like to get a maximum value (maximum value = user defined).
I've tried out a couple of things:

Manually adding keyframes (this breakes the correct values when the sun's path deviates from eg. different seasons.)
Adding drivers (also breakes the correct values over time, and I don't have a lot of experience with drivers and their possibilities)
Using the sun's greatest height in additon of a constrained parented object to determine a min. and max. value (this also deviates when using different times of the year. I felt like I was really overthinking this one)*

Note:

If possible I'd like to get an additional proposal for adding some sort of fallof to the values so their values don't change in a linear way as much:

Is it possible to get these values in both object and world shader nodes?

That can be similar to this (replace the camera by the lamp): https://blender.stackexchange.com/a/147730/19156


text:
Anyone else having wrongly named boolean settings?
It seems that when I use the boolean modifier it switches the resulting boolean option between difference and union.
This can't be normal right?
I'm using blnder 2.75

Can you explain better? You ask to difference the 2 meshes in figure one and nothing happens?

Yes, I ask to difference but I get an output that is union. and vice versa.

Recalculate normals (Edit mode > select all > Ctrl+N). Related - http://blender.stackexchange.com/questions/46399/boolean-does-not-slice-correctly-using-difference

It happens to me too. When I get the wrong boolean modifier and I can see it I just keep changing it until it works.

This can't be normal right?

Funny, it is because of normal(s). Recalculate surface normals with Ctrl+N in editmode. Also make sure the scale of the object is not negative (apply scale Ctrl+A)
Normals specify what is considered outside and what is considered inside of mesh. Booleans take this into account.

Would be useful if you mentioned how you can tell that normals need to be recalculated.

Thanks!
I feel kinda ashamed I dind't think of that. It didn't even occurred to me because I started out using basic shapes.

@RayMairlot You can tell it needed this by the dark purple/grey color of the mesh geometry.

@RayMairlot There is no specific way to tell - when you scale an object to negative values you won't see a shading difference. There are other situations when shading looks the same. You can tell by the booleans working weird - that's about it.

@Jerryno I was alluding to the fact that the shading of the objects in the screenshot were dark, indicating inverted normals. I just thought it might be useful to include that that can help deduce that normals are the issue.

Let's simplify the example.
If you want to difference one mesh from another one like the example

Take 2 DIFFERENT MESH and in the first one select the modifier Boolean.
NB BEFORE DOING THAT REMEMBER TO CHECK (could be your problem) that both the meshes have faces not oriented inside. I.E Select first mesh - EDIT MODE - Ctrl+N
and then you can use the modfier right
press apply and you did it!


text:
File optimization: Duplicate or linked duplicate?
I'm currently in the process of optimizing my blend file.
I am still relatively new at blender and would like some documentation on file size and render time reduction using linked or unlinked duplicates.
For Example: I have a architecture scene wich is currently 2GB in file size with a LOT of trees and bushes. Should I best use duplicates or linked duplicates? and what are the advantages/disatvantages? could I cut down on render time and/or file size?
As a former 3ds Max user I was quite familiar with proxys but I don't have the  knowledge to apply this technique in blender (yet).
Therefore I'm reaching out to this awesome blender community for a little help.

related: http://blender.stackexchange.com/questions/19736/how-can-i-save-memory-in-cycles-when-i-have-a-lot-of-duplicates/19739#19739

Especially in the case of things like trees you could use linked duplicates.
You can create those with Alt+D.
But if you have already created the normal duplicates in your scene you can still link them by selecting all objects that you want to convert to a linked duplicate, then select-click the object that you want to link them to and press Ctrl+L in object mode and choose "Data".
That will turn all these objects into instances. That means they share the same mesh. However, you can still transform the objects, by moving, rotating, scaling so that they look a bit different.
A common problem when using Linked Duplicates is that this will usually also mean that they have the same material. However, you can also have different materials on linked duplicates by changing the material link in the material tab in the properties editor from "Data" (which means the material is linked to the mesh) to "Object". By doing so you can have objects that share the same mesh and still use different materials on them.
That way can decrease the file size A LOT.

Another way to add many objects (like e.g. trees) to your scene is to use Group Instances. Usually this is done by having a separate blendfile for the object that you want to use as an instance, or, so to say, as a library object.
Example
Create a file with the tree. Select everything that belongs to the tree (but not lamp or camera) and create a group by pressing Ctrl+G. The outlines and wireframe will turn green to indicate that these objects belong to a group. Give the group a proper name ("tree" e.g.). Save the file in your project folder. In your main scene file, open the file menu (F1) and choose "Link" (or use Ctrl+Alt+O right away). In the now open file browser you navigate to the tree file and click it. That will bring you inside the blendfile directory, where you can go to a folder named "Groups". There you can choose your group ("tree") and link it to the scene. The tree is now attached to an Empty object. You can duplicate, move, rotate and scale this group instance, but you cannot edit the mesh or material, because all the data is linked in from the original file.
This is probably the cleanest way to add library objects to your scene.

Thanks, I got my file size down from 2GB to 1.2GB converting the trees to linked duplicates

I'm not sure that the benchmarks you seem to be asking for exist, that is, what the cost in render time and file size is for various options that affect file size. And some of this may be of more important earlier in the workflow. For example, if you are contemplating a stand of trees, you can decide earlier on whether you're going to have a more natural stand of trees, containing a half dozen or dozen trees (like a wild grove, in nature), or whether the trees are going to be more like an orchard, consisting all of a single type of tree. In the latter case, you can use linked duplicates of a single mesh; in the former, you might need to duplicate multiple types. Depending upon the specific trees, you may be able to use duplicates of several objects. On the other hand, in a "native" grove, even consisting of a few species of tree, you might find use of duplicates much more limited on account of taking to account the different sizes of trees on account of their diverse ages. A similar situation might apply to an interior scene. You might need only one type of seat in a model of the interior of a movie theater, for example, where you need dozens of type of individual chairs if you are modeling a furniture warehouse.
There are other factors that can affect the file size, too. For example the best decisions you make about the exterior of buildings in the scene can have an impact. Consider two nearly identical buildings to be seen very close up. A brick wall, up close, may have a vastly larger size because of the much greater number of bricks needed to cover the surface of the wall than a wall of the same size which is concrete construction, with a wall sided with wood somewhere in between. So, if you're going to have three buildings, one with concrete walls, one with wood siding, and one of masonry construction, your choice of how to place these buildings will have a bearing on the file size. Placing the masonry building closest to the camera may well result in a much larger file size than if the concrete structure is closest, because in the latter case, the masonry building can be suitably modeled with image textures, where in the former one, each brick may have to contain a eight vertices.


text:
Why does the ambient occlusion pass result in a black environment?
Why does the AO render pass result in a black environment?
Shouldn't this be white as default?
Also, Is it possible to get a transparent environment within the AO render pass?
White should do just fine as well.
PS: I know there's a workaround by making use of the Object/Material index to mask out parts of a layer. but this is really tedious if you've got a large complex scene.

Hate this too, makes no sense. You could put a White plane far away from the scene and only enable it to be seen by diffuse rays, should be visible in AO pass I reckon. It is a workaround though.

This could work for a simple seen which only requires AO.
Problem with this technique: It would cancel out the environment texture.
Which in it's turn could be made visible though by using 'is camera ray' etc. in the node editor. But yet again...tedious workaround :)

AO render pass result in a black environment cause it doesn't contain Alpha channel.To get any AO You have to have some objects in field of view, otherwise there is nothing to cause Ambient Occlusion.
There is a very simple way to achieve AO pass with transparent background.
In the node setup You have on the attached image (assuming, that You have transparent background enabled) You just need to attach Alpha output from Render Layer Node to Alpha input in Composite or Viewer node.

authors: Диана Костромитина


text:
Colors from imported image in compositor aren't displaying correctly
When importing images for use as a starting image in blenders compositor the colors do not display correctly.
I tried different ways to fix this issue but can't find a solution.
My guess would be that it's a gamma issue but I can't be 100% sure.
I may be colorblind but can still notice that this isn't right. :)
Any suggestions?
Import image node:

Original image:

Imported/Saved image:


text:
How to achieve a flat colored render pass from material id/index for masking
I'm trying to get a render pass that splits all different materials into flat shaded objects (like material id in 3ds max) with anti aliasing.
The output colors aren't important. (random colors are just fine as they will be used as masks)
Render engine: cycles
 NOTE: I do NOT want to use python for this.
What is the simplest way to achieve a result like this?
And...should I use seperate render layers to get the best render time?

I was looking for a solution to this problem from the very first day since I have switched to Blender 4 years ago. I understand the benefits of Cryptomatte and different ways of usage. But I wanted just one easy pass with material ID with every render, which I can save to PNG and use in Photoshop. In the end, I have made my own addon. If it could help anybody, please enjoy it. https://blendermarket.com/products/cid

You ask a question to which there is no simple answer based on your requirements:

no python - this limits any automation and implies a lot of work
with anti aliasing - this is something cycles cannot do yet on masks

The anti-aliasing issue of ID masks (first render, second without, last with):

The perfect solution would be to render the scene with each material being a different color emission shader of strength 1.0 - without python this is time consuming to set up. Low samples would be enough for this and you would get the exact anti-aliasing like in your final render.
Another solution is to give each material a different ID and render the MaterialID pass in ridiculously high resolution and then down-scale. The good news is you will get the pass with just 1 render sample!
In compositor you will get all the colored ID masks (but aliased) like this easily:

The anti-aliasing after down-scaling will not be pixel-perfect with your final render and will depend on your downscaling algorithm.

You can actually do exactly what Jaroslav Jerryno Novotny suggested (except normalize, just divide by your highest index there) in the material itself.
Create an override material for a 2. RenderLayer, use the node setup above and you can RGB split, or put your tint colors in the material directly. That way it's anti-aliased and will actually take DoF and MB into account.


text:
Objects losing their transformations in scene when re-opening saved file
A couple of imported objects (.fbx) always return to their original location (center of the scene) as they were imported when saving and re-opening a scene.
I tried to apply transform, scale and orientation using ctrl + A without any result.
What could be the issue? I feel like I'm running out of options here.

I don't know the issue, but maybe there is a simple workaround. You could create a empty at the middle of the object and parent the object to the empty. I hope it helps.

Thanks for the comment, yes it should be a possible work around but I do not want to over complicate the scene as it already is pretty complex.

FBX files often come with default pose "animation". Make sure the objects don't have animation keyframes. You can tell if the location boxes in the properties-panel are yellow or green. Also if navigating between frames with left / right arrow keys causes them to reset.
As for workarounds you can make a new mesh object like a cube and navigate to "Mesh" tab and use the mesh dropdown to select the mesh of the imported object. That way you should have a clean, unmodified object using the imported mesh.

It was indeed the animation that caused the problem I was having.
Used spacebar -> clear animation data to get it resolved.
Thanks for the help!

I often noticed imported fbx were parented to the center. I used to alt + p to unparent them and position them manually, quite time consuming.. Now I avoid them and get objs instead.


text:
How to scale multiple objects on a given axis?
I made a simple model of a house (fig.1) .
Now, I want to copy the house and mirror it negative 1 on the Y-axis in global orientation.
It should give me an exact mirrored copy of the original but instead all of the different objects get flipped in unwanted directions (fig.2) .
The house contains multiple objects (roofing, windows, doors, etc.)
I've run into this problem once or twice in the past but did not find a solution or why this is happening, nor could I replicate it in a clean blendfile.
(I know about the transformation orientation settings as well as the different options to set the pivoting point of one or multiple objects.)
Does someone know why this is happening?

Parent the duplicates to an Empty and then scale that empty by -1 on one axis.

Nice tip, thanks! This way I can apply the scale and rotation after I mirrored the objects. only thing to keep in mind, as always: flip the normals :)

Before mirroring, apply rotation and scale to all of your objects Ctrl+A.

Thanks for the comment, however I can not apply the rotation and scale because some objects are linked duplicates (ALT+D) .
This should not make a difference as the transformation orientation is set to 'Global' right?

It makes the difference: you should apply rotation and scale to the original source objects (and it's a good habit to always apply rotation and scale after modeling, exactely to avoid this kind of problems).

There is a workaround: if an object is rotated 30 deg on the X axis you can set the rotation to 0, make the mirroring, then set the X rotation to - 30.

The workaround solves all rotation issues, To bad that I have to do this manually for all objects where the rotation is not zero. Guess I have to figure out a new workflow for future projects. It still blows my mind that the Global orientation does not affect this.


text:
How to apply uv-mapping post-modifier?
I am trying to apply uv-mapping to an object after adding a solidify modifier to a plane.
The problem that I'm having is that the mapping is applied to the plane and not the resulting solid body. (which causes texture stretching)
It's important that I can keep the modifiers, so applying the modifiers is NOT an option.

I'm looking for something similar to 3ds Max's uvw-map with a box projection in the modifiers panel like shown in the image below:

Geometry generated from a modifier is not directly accessible until after the modifier is applied. Otherwise, we would be able to control each UV vertex of an object with a subsurf modifier before committing to it.
Please explain why you must keep the modifiers, so that we can help you find a change in workflow to answer your question.
For now, the answer is that it is not possible to apply UV mapping to geometry made from a modifier that hasn't been applied.
Here is an example of a possible work around that may meet the behavior of your 3ds Max reference. First, I'm making these assumptions about your workflow:

You are using a repeating texture that doesn't rely on precise UV
positioning.
You are creating assets for rendering purposes.
You are using Blender Render instead of Cycles (May work, I'm not
experienced with it.)

Instead of using a UV-map to determine the texture positioning , Assign a material and texture to the object and use its texture properties to map an image to generated coordinates using a cube projection.

The results will not be reflected in the view-port (You must use view-port shading set to material to see it), but creating a render will show the texture projected on all sides.

Thanks for the explanation! To explain my workflow a bit better, I'm indeed using seamless textures or procedural in some cases.
I'm not so much creating assets and I'm rendering in cycles.
The reason I'd like to achieve this is that I always strive for a non-destructive workflow. For this project in particular It's an architectural visualization where I'd like to easily be able to tweak the thickness of the window sill at any point in time without losing uv-mapping data.
It's the workflow I had in 3ds Max and this worked out great for me in the past.

I recently managed to achieve in Blender 2.79b exactly what you wanted to do, I just checked that if it was already possible in the 2016 version 2.77a. You only need to add a UVProject modifier after the Solidify modifier that you don’t have to apply, and add some empties as projectors to specify in the "projectors" field of the UVProject modifier. For your example where you want a full "box" mapping on the 6 faces, you need 6 empties with their Z arrows pointing in the 6 spatial directions X+, X-, Y+, Y-, Z+, Z-, and you can also scale/move them if you want to adjust the texture scale/position.

That enables to project textures with a virtual UV mapping on the "rim" faces generated by the solidify modifier. With this setup you can for example export your objects to SketchFab without applying anything: on this model https://skfb.ly/o7WuC I created all the wooden lacework, stairs and balustrades of the mansion this way (other different but similar case, I also managed to apply textures on the bulbs without applying the Screw modifier, using a UVWarp modifier)

Octane for blender can do that. In shader editor there is a "box projection" node you input in your texture's "projection slot". Works with solidify perfectly. Cant find this in cycles as well :(


text:
How to change world background based on active camera?
I'm trying to create a scene consisting of multiple cameras which all should have it's own unique environment. But I'm having trouble setting up an automated node setup.
How can I setup the world node editor so when a certain camera is set as the active camera, the correspondent background is activated for rendering?

EDIT:
Blendfile for testing:

one (different) way could probably be animate the world settings in sync with camera switching... or, link objects (not cameras) to more than one scene, and set each camera in different scene, changing scene world settings...

@m.ardito This would be a nice enough workaround for a simple 'still' project. I already looked at using the timeline to change cameras and nodes. But this will cause conflict when rendering animations.

I was editing my comment, updated.

I found numerous of workarounds but I consider these as a 'dirty' workflow.
I also want the solution to be scalable for future complex projects.
Therefor the node editor should be the way to go I think.
For example: when linking a lot of scene objects you'll lose a general overview of your project. When making lots of adjustements this will most likely result in missing or unnecessary objects in certain scenes...

maybe you can use a "script" node to switch world output setting different "background" nodes strenght based on active camera... ? that would require creating a python script, though, I can't yet help with that...

I don't think you can access active camera from inside a shader, so it is fundamentally impossible to do what you want directly without workarounds. You should probably setup several different scenes with linked objects so they are kept in sync, and add different worlds to each, and different cameras

Actually, I believe it is possible with drivers - to capture the location of the active camera - and you can then set up your environment to react to that stored location. I have successfully tested this and it's working (so animating the active camera is successfully updating the scene). I'll write up and submit a proper answer later.

If I were Python savvy I would probably approach this by writing a script that when rendering, for each frame gets the name of the active Camera, and then chooses a World with the corresponding name.

This can be achieved using Drivers to feed an attribute of the Active Camera into the Environment material.
The current active camera can be determined using Python (as defined here) using :
obj_camera = bpy.context.scene.camera

We can distinguish between the different cameras by setting the Pass Index of each camera object to specific values - eg, 1, 2, 3.

In the Environment material, add a Value node, right-click the value field and select 'Add Driver'.
Ensure the Value node is selected and swap to a Graph Editor window and select Drivers. Highlight the newly added driver and open the properties panel with N. In the Drivers panel, set the Type to Scripted Expression and set Expr to 'bpy.context.scene.camera.pass_index'.

Note : You'll need to enable the File/Auto Execution/Auto Run Python Scripts option in the File/User Preferences settings if it isn't set already (this allows Blender to run Python code).
You should now find that as the Active Camera changes the value of the Value node in the Environment material changes to reflect that camera's Pass Index and this can be used to generate values (using Greater Than/Less Than maths nodes) to drive the Mix Shaders to select the desired material.

Note : The displayed Value value for driven values doesn't always update immediately in the node tree - but the actual value used by the Environment material is correct (it has simply not been refreshed on-screen). Moving the mouse over the Value node should trigger the display to refresh.


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How to force compositor nodes to execute?
Whenever I add certain compositor nodes after a render is done, it doesn't execute these automatically without re-rendering (By automatically I mean whenever a change to the node setup is made, regardless the state of the rendering process).
I'm specifically referring to the ''file output'' node here.

Is there a way to force this node to execute?
(Automatically and/or manually)

So, it turns out there is no easy way (if any) to trigger either compositing or file-save in both the GUI and the Python API. Or at least not without re-rendering the image.
Based on this anwser I made an extension that does the following:

Make a new dummy render layer
Disable all scene layers
Render the dummy layer (and only that layer)

As a byproduct it will re-composite all your render layers and thus re-trigger the compositing of your image.
Afterwards it will delete the dummy render layer.
To make it easy I made it so that you can search for "recompose" by hitting space or hitting the "Recompose" button in the Node Editor when you're inside the Compositing Node Tree.
You can find the addon here: http://cloud.webvi.be/index.php/s/NYbHNlrVX4ZikXn

Good answer. One thing would you put the addon on github? I don't like random file sharing sites. (plus the link is not permanent)

@Wouter The link is dead, basically rendering this question effectively empty. This is not a regular forum, according to site rules links to answers are not answers if the link goes missing your answer becomes an empty shell without content. Answers should be substantial and stand on their own without relying on external data like links, videos or images. Instead of having users go through external links, either transcribe essential parts of the process here, linking the source, or posts these in the comments section instead.

Generally Ctrl Shift click on the last node connect the viewer and force a refresh of the compositor nodes. If it fails, you can use an UV editor window, choose "viewer node" and save the result as image, without a new rendering.

Hi Josh, thank you for your response.
Refreshing the nodes isn't the problem.
Also, this is just an example. My real workflow requires an autosave on multiple file outputs. This would be really tedious to do manually with the F3 ''save as image'' command.

Ah, ok! It can be useful for others users.


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selective color correction
I am trying to change the colors of an image texture separately but I can't figure out how to do this.
Every color correction I make results in a color change for the other color as well.
What can I do to change for example the greens to blue and Reds to yellow?
Also, is it possible to do this for an image containing 3-4 different colors?

How to do Color Correction in Blender https://youtu.be/NN8rxOumzyU

See https://blender.stackexchange.com/a/194471/35559


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Getting limited random node values
I'm looking for a way to get a random value between 2 given integers.
As an example:
In this particular case I need to get a random blackbody value that's between 3000(min) and 5500(max).

Any thoughts?
Thanks in advance!

This can be solved with some (for my level) clever use of the math node:

A quick rundown of what the nodes do in this case:
Subtract: calculates the difference between your desired minimum and maximum value. In other words, the maximum amount of variation that could happen, in this case 2500.
Multiply: Multiplies the previous calculated value with the output from the Random value of the Object Info node, which lies between 0 and 1. This creates a random value between, in this case, 0 and 2500.
Add: Adds the randomly generated value of the Multiply node to the mininum value you have specified, resulting in a random number which cannot go below your desired minimum or above your desired maximum.
In this case what happens is:
3000 + value between 0 and 2500 = value between 3000 and 5500
(No i do not know the proper math symbols, but I think you get the point.)
Result:


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How to delete 'Mark Sharp' edge properties?
I have a model which I've given some sharp edges using the 'Mark Sharp' function.
Now I want to edit the model and remove all the properties of these edges.
I want to keep the edges. I only need the 'Mark Sharp' to be removed.
(note: I don't care about losing the UV-mapping data')

If you used Mark Sharp function, then you probably noticed Clean Sharp just below it. Select the edges and use it (Ctrl+E>Clean Sharp).

Thanks! Problem solved.
One thing though:
I mostly use the spacebar for quick acces to certain functions.
I noticed this option did not display in the quick search, however it did when I entered the CTRL + E shortcut. Is there a reason for this?

I don't use quick search very often and I have no idea why, although it's an interesting observation.I don't see any obvious, logic reason.


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How to do basic parametric modeling onto a spline
I'm looking for a way to do some basic parametric modeling in blender.
I have 3 pieces i'd like to use as a base.
1 starting section, 1 middle and 1 ending.
Is it possible to generate a combined model onto a spline using the starting and end section to close off the model with one or more middle sections based on the total length of the spline?
Example:

Starting from this thread (Make a 3D tube with a bezier curve), I figured that the curve modifier had to be used somewhere. First the spline and the length however.
Use  the following spline settings:

For the length of your object, you can use the array modifier with "Fit Type" set to 'Fit Curve' and then select the curve you want to trace. Then pick your start & end cap. Next up append the curve modifier and take the beziercurve as the object. (deformation Axis = x)

Lastly figure out how to reposition your endcaps so the vertices close up. (I haven't fully grasped the math behind this myself).
EDIT: Considering the end caps. Turns out the array matches them perfectly when you just 'snap attach' them in edit mode to the middle section that you want to array. As in the picture below.


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How to scatter objects based on texture color data with Geometry Nodes?
So the idea is to interpolate a heavily pixelated image into 4-6 tints of grey.
Based on the value of that local pixel I want to add a specific object.
The plane will be subdivided into the corresponding pixel sections. (This should make it easier to distribute the objects in my opinion)
Is there a way to achieve this using geometry nodes?
See image below for the result I'm trying to achieve:

i think it is not possible with a pixel dependency because Blender works on vertex/faces/edges basis.

@Chris I feel that there should be a way to do this given we have an ''Attribute Color Ramp'' & ''Attribute Sample Texture'' node. I will be subdividing the image so that the edges are touching the pixel borders, this way I would be able to distribute on faces.
Just need to figure out how to extract multiple specific color values from the texture.

If you translate the positions (in this case the Faces of a grid) to a range of 0-1, you can capture the color values at certain positions of an image.
You can then translate these positions directly into indexes with the node Map Range, which will select the corresponding object from your collection as the value for Instance Index with the node Instance on Points.

Here is a summary of the node group that leads to the described result:

Here is the blend file:


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Applying a curve modifier to an extruded plane causes plane to become a line
Surely this is some setting that is wrong, but what?? I trying to bend an extruded plane using the curve modifier, but as soon as I select the bezier curve in the modifier, I lose all dimensions of the plane!  Top down ortho of plane & bezier curve before modifier

Probably something with the curve, e.g. its Radius parameter (see in Edit mode on the Properties shelf > top rollout, it should be set to 1 to get expected behaviour), but not necessarily. If you can upload the  blend and include link here

Is there any scale or rotation involved?

Also see https://blender.stackexchange.com/questions/64579/why-does-adding-a-curve-modifier-move-my-object-to-the-center-of-the-curve and https://blender.stackexchange.com/questions/51909/mesh-deforming-when-add-bezier-modifier . This has been asked countless times, I'm sure following the steps on those questions will yield good results.

It is possible to get a flat path using only a curve object, by setting the extrude property. You can also add a solidify modifier to give it some thickness.

The extrusion may not align the way you want at first, adjust the tilt to get it right, which can be found in the properties region N. You can use ⎈ CtrlT to adjust the tilt interactively.

If you want a mesh object after you have created your path, ⎇ AltC->Mesh From Curve will turn it into a mesh.

There was a scaling problem (even though I applied scaling & rotation) but I couldn't find the Transform > Radius that Ramos described. I found that if I zoomed in far enough, what I thought was a line was the horribly deformed extruded plane. I tried numerous re-scaling of both the plane & the curve, and with the hint that Mr Zak supplied, went to the Bezier curve's shape properties, and unchecked 'radius' (path/curve deform) and set Minimum's Smooth (Twisting) value from 0 to 6.00. Mostly by luck(?) I got the desired results. Mission accomplished! Thanks all.


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Cycles: Front plane's alpha pixels getting 'canceled' by rear plane's alpha pixels
I am rendering a scene with three planes that all have emission shaders.  Farthest from the camera is the room plane (#1) with a movie texture, close to the camera is the face plane (#2) that has an RGBA movie (alpha channel) texture, and flying across the scene is a plate plane (#3) that has a PNG image texture (alpha channel).  Lighting is irrelevant, since there are no other objects in the scene. The #3 alpha is working as it enters the scene (the green circle below), but as it moves in front of plane #2, #2's alpha bits are turning #3s alpha bits to black (the red circle below).
Here you can see the object view with the two planes overlapping (the plate plane is rotated about 45 degrees) When #3 completely overlaps #2, the plate is surrounded completely by a black square.
The transparency is accomplished with the "standard" set of nodes on both planes #2 & #3.

I see that in your second screen shot, in the Render Context Tab, under the Film panel, "Transparent" has not been enabled. Have you tried enabling it?

YES! Cegaton you nailed it.  The Light Paths transparency (both Min & Max)  were set to zero as I erroneously thought that since there were no lights in the scene, that wasn't needed. I failed to understand that the setting also related to the EMITTED light from the emitter shaders.  One bounce is all it took!  Cegaton, please post the answer & take the credit.


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How does the Vector Math Normalize node work?
As I understand, the normalize setting should convert a vector into a unit vector. However, I am confused as two what the second vector input does in this operation. Normalizing should only require one vector input right?

For the normalize option the node will only normalize the first input vector (set the length to 1). You are right, a second vector isn't needed for this operation.
This example shows how it can be used to multiply a vector by a scalar:

I recently encountered another instance of this with Cycles nodes where only one of the inputs is actually used.  I think this was done to avoid the extra code needed for lots of different node configurations.  It is confusing.


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Is it possible to store rigid body cached/baked data into an external folder?
Is it possible to store rigid body cached/baked data into an external folder, instead of directly in the blend-file so that the file-size is not too large? I feel that storing the data externally seems more convenient, as then I have more control to bake in chunks.
This is an opposite question to Is it possible to bake fluid simulation into blend file?
Similar to rendering an animation to individual frames and convert to video afterwards, so that it is possible to render in chunks.

The storing is to external folder I mentioned is the same way as baking fluids

No, there is no option to bake to external cache.
The workaround would be to convert simulation into an Action: Viewport header > Object > Animation > Bake Action (turn visual keying on).

You can store this action in another .blend to link it somewhere later, or in another file format you can import where you like.
If you want to simulate in chunks, you will have to animate the Animated tag under Rigid Body settings to control till which point is the last Action and where the simulation continues.

thanks! could you give an example? I cannot find the viewport header


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Double simulation time to achieve 0.5 speed effect (slow motion)
I have a rigid body simulation set up, but I would like to double the simulation time; each frame in the last simulation, should last 2 frames now. I keep the same frames per second, to achieve the 0.5 speed effect (so actually scale time by 2. Does someone know how to do that? Thanks :)

Go to animation then go to dope sheet summary and press A, make that the diamonds become orange then S and press 2, use G to move the diamonds to the time you expect.
If you have no diamonds put animation and go the panel with the cube and put the start time<(frame), press I, select locrot, then there will appear diamonds, same to the next frame

Thanks, but if I understand correctly this will only work if keyframes are used, right?

yup, but as you can see is easy

Yo guys, I am late and the post is dead, but for you people using Blender 2.8+, there should be in the flip options the [Time Scale] slider, use that.

sorry but you are thinking of fluids. This question is asking about ridged body


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Intersected meshes make chain break
When I use Rigid Body physics and the meshes intersect each other, like the picture, the chain breaks when simulation (AltA) is done. I use 'mesh' as collision shape and increased the solver iterations and steps per second. What could I do to make the chain not break when I do the simulation? Thanks :)

Could you add the .blend? Maybe lowering the mass of the objects could help (they are quit thin) I had this when animating a chain it teared off until I tweaked some params, unfortunately the my .blend is gone: http://blender.stackexchange.com/questions/13916/how-do-i-animate-a-character-with-dangling-chain

This is the blend file: http://www.pasteall.org/blend/36320

I made the meshes heavier, because I thought that more mass means stronger connection, at least that's what I've learned :)

My Blender crashed so I updated to 2.74 and it still is freezing with you file. Check the Sensitivity param it should be > 0

Since I had no luck with your file I created someting compareable.
Getting this working is tricky. You need to find balanced parameters most important are mass and sensitivty.
A mass of 100 is way to much and sensitivity should be > 0, e.g. 0.01 (probably blender units).

With a mass of 1.0 the simulation breaks after 90 frames:

When the mass of the second ring only is increased to 2 it works as expected.

Thanks, you made the first chainlink 'active', but unchecked 'dynamic' right? Or did you make it 'passive'? But my chainlinks are more complex, does it make it more difficult to tune the parameters?

@FacebFaceb The first one is set to passive otherwise the whole chain would fall down.

Yes, but if you make the first chainlink active, but turn off 'dynamic', it won't fall down and the chain has less chance to break


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Is it possible to have a plane with its normal as reference for Transform Orientation
Is it possible to have a plane with its normal as reference for Transform Orientation (Global, Local, Normal, Gimbal, View axis)? For example, I would like to select every face and scale to 0 to the normal Z-axis:

But if I select every face then this normal Z-axis changes:

Ctrl+Alt+Space to create a transformation orientation aligned to the face then select all and S, Z, Z, 0

You can create custom transform orientations. The shortcut is ⎈ Ctrl⎇ AltSpace or in the properties sidebar in the Tranform Orientations panel you will find a small + that will create a new orientation based on the current selection, in this panel you can also rename and delete any custom transforms you have created.
Once you have defined a custom transform you can activate it in the transform orientation menu so that your transform manipulator is oriented the way you want.

authors: Владимир Родионов


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What are surfaces and metaballs used for?
I use very often meshes and curves, because I know what they are used for (meshes for renders and curves for follow curves). But I actually don't use surfaces and metaballs. What are surfaces and metaballs used for?

I use meta for liquid effects that are hard to achieve with mesh. Just like the liquid metal in Terminator... I think those were meta

With metaballs you can create base models quickly, that have even face distribution consisting of quads that is good for sculpting.

I can't speak for metaballs, but surfaces are the geometry you would use before computers could handle smoothing polygon models. The idea of a nurbs surface is that you have a number of isoparms, which are the control points, much like a lattice. The computer interpolates smoothly between adjacent isoparms, which generates the smooth surface you see in the viewport. It was a very efficient way to render a surface with the hardware of the time.
Today, surfaces can be used for hard surface modeling, ie cars, planes and environments, although their use is fading quickly.

Metaballs can be used to simulate some "special" fluids, like ferro fluids and soap bubbles.
Most of the time though, they are just a cool effect for motion graphics :). Specially in abstract designs.
Nurbs Surfaces can be used to model any object with smooth surfaces. Their strength (compared to poly modelling) is handling complex curves smoothly. That's why they are the preferred modelling method for industrial design and manufacturing. There are even machines that take NURBS data and cut pieces for you.
Note that NURBS in Blender are underdeveloped in comparison to poly modelling.

And film production 99% of the time calls for polygons, so nurbs aren't really a focus for non-engineering development.

Didn't say they should be.


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Rotate a cube around Y axis m*360 degrees in 200 frames?
I have a cube that I would like to rotate m*360 degrees around the Y axis in 200 frames where m is an integer. So I go to frame 1 with the default cube, press I for insert keyframe and press rotation. Then I go to frame 200 and rotate the cube around the Y axis m*360 degrees. I know two ways to do this:

press R, Y and manually rotate it m*360 times with the mouse, click leftbutton and press I for insert keyframe and press rotation
press R, Y and type 'm*360', enter, press I for insert keyframe and press rotation.

However, only the former option works; the latter option will result in a rotation of 0 and result in no rotation. For small m the former manual option is okay, but for larg m the latter option would be more handy.

You can type m*360 directly in Transform>Rotation window. This would be the easiest and most transparent way to do that.


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Is it possible to export shape keys to c4d pose morph?
I try to export a model with shapekeys (a ManuelBastioni character), in order to import it in c4d. Is there a way to transfer these data to the equivalent in c4d (posemorph tag) ?
I'm almost sure I've already done that, but I can't remember anymore how...
Thx,
J

Ok, I managed how to do it :
In the blender fbx export options, "apply modifiers" must be unchecked :

Import fbxinto c4d, and so are the blender's shape keys converted to c4d's pose morph :


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Importing textured psd into blender not showing correct colors in blender
Im using blender 2.75a. After I export my uvmap from blender, edit it in photoshop and try to reopen the psd file in blender. I don't see the changes I made in photoshop. Instead I see totally white background and no textures applied on my character. Is there some other way of texturing uv map in blender 2.75a? or am I doing something wrong?

Even though PSD is not presently listed among Blender's supported image formats, it is partially supported. Some PSD features will work and some will not.
Excerpt from the link Ray Mairlot has provided:

What works:

8-bit images (with or without alpha)
16-bit images (alpha discarded)
Photoshop files saved with 'Maximum Compatibility'
Cycles, Blender internal,  BGE (and player)

Known limitations
(due to OIIO dependency):

Images with less than 4 channels show a wrong thumbnail (bug may be in  OIIO)
Packed images are not supported
We do not write PSD files.

So if you want to be sure your images will work in blender, you can either:

Export your texture in a fully supported format instead, such as EXR, TIFF, JPEG, or PNG. (If it contains transparency data, use PNG, EXR, or TIFF.)

-OR-

Stay within to the guidelines of "What Works" to keep your PSD files compatible.

Well that did import the png file but it doesn't seem to be applying the texture. Anything else I have to do?

Thanks bro. Got it. I used to nodes to apply my image as a texture.

Glad it's working for you :-)

It may not be mentioned as a 'supported image format' but PSDs are supported: http://lists.blender.org/pipermail/bf-blender-cvs/2013-October/059753.html

@RayMairlot Hey, thanks for that info! I wonder why it's not listed as a supported format. Maybe it is considered to be partially supported?

Perhaps, or the documentation just isn't up to date.

@cegaton Done.  :-)

The thing for me was making sure the psd was in RGB format, not CYMK or something else.


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How modeling a complex object into a shape draw by a sharp line?
After hours of tutorials, and the first help of Carlo, I'm looking in a way to force an object, like a "bone" (so not exactly a regular cylindre, with a lot of meshs) to shape itself into a sharpe path of 3 or 4 points (path converting in meshs after alt+C, let s call it "a guide").
So the idea is to use this guide like a tool to shape the bone object linked and without deformation (like a solid object) as you can see :

So to begin with... it s difficult : because it s not a bezier item, it s a complexe cylindre. So I can t use "bevel object"  with an object like that...
After this step, I think there are two possibility to see the problem :
1) You can superpose pieces of the bone if they split on an exact point of the guide (so exactly on the point between two lines). I will know how I have to "cut the bone" (so remove littles triangles) to shape it exactly like the guide (with boolean union modifier for exemple!), but like it s an object more like a triangle long bone object, one of its faces is large and have to be always at the bottom part of the modeling...
So 2) No superpositions but a complexe serie of movements (spin, translation,..) of the pieces on after the other to touch themselves in a "solid" mode, to force the large face to be always at the bottom...
Like that the little triangles removed will be much more smaller +++

I know it s very difficult to have the 2) option. S I think the first one with boolean modifier will be more than enought (but if you have an idea of course..).
Thank you so much for your time and help in this difficult modeling!!!!!

I think i found something, not really easy.
Create an armature, enter Edit mode, make it flat and subdivide the bone (W, subdivide and choose the number)

In pose mode (Ctrl+Tab), rotate and scale your bones to fit the shape you need

Select all your bones and store the pose in the pose library, we'll use it later. Now cancel the rotation of your bones and apply the pose as the rest pose.

Now add a cube, in edit mode, move the faces to fit the armature and add an edge loops for each bone joint. back in object mode, parent the mesh to the armature (select mesh 1st then armature, Ctrl+P, choose automatic weights)

Now select your bone object (the thing that you'll cut) duplicate it with Shift+D, move the duplicate to the armature and parent it to the 1st bone (select the mesh then the bone, Ctrl+P, choose bone). Do as much duplicates as you have bones and parent them the same way.

Now select all your bones (armature) and apply the pose your stored earlier and clear the scale (menu or Alt+S)

If the cube mesh needs it, correct the vertex groups. This should be simple with a lowpoly mesh and few bones.

Now apply the armature modifier on the cube and in edit mode separate the elements (select and P). Add faces to close them.

Now you have 3 cubes usable as booleans to cut the 3 bone objects where you need. You can easily move the bone objects along their local coordinates for minor adjustments.

Thank you soooo much!!! It s working very nicely! amazing idea to combine the cubs with the armature first to use them like boolean modifiers after that! I can complete my work thank to you Bithur. You are the best!

Glad to help :) Think about accepting answers : http://blender.stackexchange.com/q/35459/11431


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How to make an edge copy the shape of other edge?
I have a plane that I use as canvas with dynamic paint and a sphere that I use a brush with dynamic paint too, so they both produce a wave:

My question: how can I make the edge (red) copy the edge (blue)?

I'm trying to clarify what you are looking for in an answer to this question. Are you hoping to find a solution that would mimic the cross section of the (blue) edge on the (red) edge throughout the animation lifetime? In other words, if there is no waves affecting the (blue) edge, then the (red) edge is strait, but when the wave(s) deform the (blue) edge, then the (red) edge shows the same deformations?

yes you're correct :)


text:
How can I make duplicates of an object using empties as placeholders?
How can I make duplicates of an object using empties as placeholders? For example I have a cube as original. After that I place some empties with a certain position, rotation and scaling and then turn those empties into duplicates of the original cube?

First select the cube and create a group Ctrl + G
Then select all your empties and go to the Properties Panel > Object > Duplication click Group and then choose the newly created group from the dropdown.

If you have selected more than one empty, hit Ctrl + L with all of them selected and click on DupliGroup to have the Group property copied to all of them.


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I deleted a preset, but can't reobtain with Load factory settings
In the recent version of Blender, panel Properties, Render tab, Dimensions section, I deleted a preset, but I can't reobtain it.
I tried this: File > Load factory settings, but it doesn't affect the presets.

Somewhat related http://blender.stackexchange.com/questions/62597/how-can-i-recover-camera-presets-in-blender/62600?s=1|0.9838#62600   render presets can be found here https://developer.blender.org/diffusion/B/browse/master/release/scripts/presets/render/


text:
material groups are linked with another, how can I unlink them from another?
First I will describe what I have done:

In node editor, I added material nodes
I selected material nodes and grouped it
I duplicated the group
Then I edited one of them

However, when I edited the duplicated group, the same edits and the same modifications were applied to the original group too.
My question: why is this and how can I unlink them?

Click that number next to the group name:


text:
Does Blender have different languages (language as in speech language as english, not computer language as python)?
Sometimes it's more convenient for me to use Blender in another language. Does Blender have different languages (language as in speech language as english, not computer language as python)?

Yes you can change the default interface language in blender.
To do so open the User preferences, go to the system tab, on the bottom right of the screen there is a checkbox that says "International Fonts" check it then select one of the translations then choose to apply it to "Interface" or "Tooltips" or both.

Also note that not everything has been translated, some languages more than others. If the language you use is not complete or is non-existant, you might want to consider contributing.

In Blender 2.8x to 2.9x the language/translation preferences can be found in Edit > Preferences > Interface > Translation.
The translation can be selectively applied to different parts of the UI as explained in the manual:

Tooltips
Translates the descriptions when hovering over UI elements.
Interface
Translates all labels in menus, buttons, and panels.
New Data
Translates the names of new data-blocks.