text:
Comprehensive list of 'missing' features in Blender 2.8?
I am considering moving from 2.79b to 2.8, but I am still unclear of what 2.8 doesn't yet have. Is there a list of all the features it lacks (in comparison to 2.79x).
All I have so far mostly is this from 2018.

Currently, a few areas area still being completed:

Stable and well documented Python API for add-ons developers.
User interface for Collections in the 3D viewport.
Keymap for left-click select that works well with the new tool system, and a new keymap compatible with other software.
Making image empty objects a fully-featured replacement for background images.
Restore support for all the physics systems within the new dependency graph.
New subdivision surface and multi-resolution modifier implementations based on Pixar’s OpenSubiv.

P.S. also interested in features missing from Animation Nodes.

Blender 2.80 has solved all of these aspects.

Stable and well documented Python API for add-ons developers.

The Python API for 2.80 is documented in the manual. The API was completed on 24th of May, 2019. It's stable in the sense that there are no major changes between 2.8x releases at the time of writing. Add-ons written for 2.80 continue to work in 2.81 and 2.82.

User interface for Collections in the 3D viewport.

I assume this refers to the updated outliner. This has been completed, collections and view layer replace the old render layer system from 2.79. The concept is explained in the View Layers and Collections post by Dalai Felinto on the developer blog.

Keymap for left-click select that works well with the new tool system, and a new keymap compatible with other software.

The new keymap system allows you to choose between left- and right-click select. You can create completely customized keymaps. There is an Industry Compatible keymap included in Blender which may help professionals to transition from other 3D software.

Making image empty objects a fully-featured replacement for background images.

There are two image object types, the Reference and Background objects. Both are based on empties. This is only for images that do not appear in the render though. If you want your image to appear in the render, then the Image as Planes add-on is still quite useful.

Restore support for all the physics systems within the new dependency graph.

The major dependency graph changes have been completed. Some technical information about the design can be found in the wiki article Blender 2.8: Dependency Graph.

New subdivision surface and multi-resolution modifier implementations based on Pixar’s OpenSubiv.

The modifiers now use OpenSubdiv which has been integrated by Sergey Sharybin.

Thanks, can I conclude then that what I posted was the comprehensive list of missing features? If so your answer has essentially cleared it all up.

The points you've mentioned were at some point tasks on the roadmap of 2.80 during the development. It's by no means a complete list. However it wasn't anything that was ever missing from the release version of 2.80. So it depends what you intend to compare. BTW in case that wasn't clear BGE and Blender Internal have been removed, the latter has been replaced by Eevee.

Noted that the list was not comprehensive. My concerns where that after having used 2.7x to learn, (and still learning) that 2.8x could potentially throw a spanner in the works by the omission something. NB I don't mean changes or replacements, for instance BGE to Eevee.

2.81 was just released, it is worth taking a look at, it solves quite a few issues and adds a load of new stuff.
In the meantime I think you can strike these off your list.

Keymap for left-click select that works well with the new tool system, and a new keymap compatible with other software.
Making image empty objects a fully-featured replacement for background images.

If you can wait until February 2020, v2.82 will have some major performance improvements, in particular for Windows users who have had some issues.

OK, TBH it didn't seem the improvements that are coming ever really benefit me, my core interest is Motion Graphics, and that be frank even as a fan of blender it feels so very neglected. Animation Nodes is powerful but man the complexity and maths needed is terrifying. And let's not speak of the text support. Anyway I digress.

2D or 3D? The improvements to grease pencil have been amazing!  Yes text is always being asked about.

Predominantly 2d but not just, I mean the type of mo graphics C4D's Mograph excels at. My fingers are often figuratively crossed for more in this area but usually it's modeling features and other 3d areas of interest. Grease pencil is great but again it's a different field/area imo

Unfortunately Animation Nodes seems to be broken on 2.8x, at least as far as I can tell.  Yes, anything node based is math-friendly, not creator friendly.

That's helpful to know, but if so not the best news TBH.

Might work on windows, I've only tested the linux package, I'm going to try and build from source.

Thanks, I'm Mac.

I have kept both 2.79 and 2.8 on my computer. I simply changed the folder name on the former so not to have the latter overwriting the other.
My reasons for keeping 2.79: one, I download creators' past works and I like viewing them in 2.79; two, some custom addons are not updated for 2.8; three, I watch old tutorials and vlogs.

OK but how do you manage the two different versions of Python on the same device? (I am Mac if it matters).

I have no problem with the two versions. I am not too familiar with Python, though I am trying to learn it. Tomorrow, if you are interested, I will make a video of my desktop & folders and post it in re-edit.

Yes. Very much interested.

@PeterAskins I will get back to you either tomorrow our Monday, when I open PC in another location. I will screencast everything.


text:
Luxcore noisy render
When I try to render something with Luxcore it get really noisy.
I read that Luxcore was working as a camera so if the image is too dark you need to add more light in the scene or it gets noisy.
I tried but instead of having RGB noise I have white and grey noise. Why?

I read that Luxcore was working as a camera so if the image is too dark you need to add more light in the scene or it gets noisy.

This is not correct. The brightness of the image does not matter.
To reduce noise, you have these options:

Render more samples
Use the denoiser (in the render settings, "LuxCore Denoiser" panel)
Optimize your scene so you get less noise with the same amount of samples, or more samples in the same amount of render time (this requires knowledge about the settings in your scene, so I can not help with this without the .blend file)

I tried to use the denoiser many times but it doesn't work, and where can I add more samples?

Also, I'm using the Bidir engine

source: Stack Exchange

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

sort: votes


text:
Reflective diamond material
I need help on how to make this kind of reflective diamond material in blender. Im doing visuals for an artist and i can’t find any good tutorials/posts on how to achieve this kind of effect.

do you want this material to work in eevee or cycles ??

Please read [ask], did you try researching the various tutorials available on the web.

I woud like this to work on cycles

do you have other pictures of the same object?

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


text:
connecting two objects
so i wanted to connect two objects in this case its a plane connected to the bottom of a head mesh, i create a plane, line it up delete a edge on the head mesh and plane and i select both vertices in edit mode and i fill them the problem is that it shows up black while the middle is simply extruding the mesh. actually im not sure why it shows up as black?, but im trying to achieve the same results as if i was extruding the mesh. shouldnt the uv map of the head be making it atleast the same color

i joined them than filled them i think it has to do with the uv map im not sure why it turns black

Pressing "CTRL-J" in object mode should join the two objects, and make them the same color. It works in my case.


text:
ON/OFF switch for smoke simulation effectors
I'm doing a test on a project with different field effects,"WIND ,VORTEX ,TURBULENCE ... etc." and I would like to try each effector independently of each other without having to delete other effectors in the scene.
Is there a simple on and off mechanism for an effector that will disable unwanted effectors?

This is controlled by the Field Weights section of the domain object's physics panel.
There are dials for each type of field, which you can set to 0.0 for OFF and 1.0 for ON.
Another way is to create a collection and seet the effector collections. Put the active field effector in that collection, all other effectors will be ignored for the purposes of the smoke simulation.  Then swap out the effector when you want to change to another field effect.

hello, very complicated the "blender" system when wants to do for example a "test" between several "simulation object", why not do as in music software or video editing, simply add a "MUTE" button and "SOLO" to each simulation or various effects object (I have been a musician for 40 years) example add a button "ctrl M" and "ctrl S" in "Scene collection"> "filter"
to "activate" deactivate ", thank you

The key bindings you suggest are already used for mirror and snap.  The weight controls provide analogue granularity.  You can always customize the UI with Python.  Your use-case is specific and would not help animators of more complex simulations.  From one musician to another, think of these as volume controls on a mixer if you prefer.  Feel free to upvote and mark as accepted solution.


text:
Glass not rendering correctly
I've no idea where this grey is coming from. Transmission 1.0 and Roughness 0

Because you didn't put thing around your platform. That's Blender default empty been rendered.

I found a fix! Apparently my normals were facing the wrong way. You can check this by clicking on overlays and checking "Face Orientation"; Red means it is reversed. I Selected all my vertices and hit shift-n and voila no more silvery things! Thank you everyone who gave suggestions.

I believe it is reflecting the world texture. Try changing the color of the world as represented below and see if the reflection of the cup remains grey.

Another suggestion, change the IOR of your glass texture. This is related to the degree of the glass, like the ones we use in the face. Try putting it into 1 and it will show the object inside without any distortion.
Hope it helps :)

It is definitely reflecting the world but no color value can help me make the glass completely clean, I tried making the world color alpha 0 but still the grey persists. Changing the IOR value to 1 makes my glass completely invisible.

Oh man, sorry then :( If you find the answer, please post it here. I'm also curious on this one.

Definitely try @Mateus Arruda's answer first. If that doesn't work, try turning down the Alpha on that same node.

Changing the Alpha definitely helps with the weird reflections but it makes my glass itself more transparent and even a middle value looks unnatural.

A combination of the two? Try turning the "Transmission" value up. Mess with IOR, Transmission, Transmission Roughness and Alpha until you get the right setup.


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Eevee viewport and render looks blurry (won't display textures and lights as expected)
I´ve been having some troubles with eevee, the thing is that it looks blurry. It won't display my textures and lights as expected. It just looks like if it was "underwater". Besides, cycles render is way more different.
Evidence annex:
First image is eevee and the second one is cycles.

Your Eevee window is showing it is still (or stuck?) rendering shaders.

Are you using an object with a volume shader ? They react differently in Eevee and Cycles and have different setting

Yes, my clouds have volume shader. Also, my eevee window is not stuck.


text:
Blender and pyopengl rendering have some differences
I'm using Blender to make the groundTruth of a differentiable renderer which rendered with pyopengl.
However, I derived Blender's camera matrix and projection matrix and rendered them with pyopengl, but there are always some small differences. Pyopengl rendering will enlarge my model a little.I don't know what's going on. Does anyone have a standard export process in this regard? What's the difference between blender and pyopengl.
Thanks very much.

Welcome to Blender.SE. I don't have any knowlendge of pyopengl, all I can say is that exporting Blender camera to other software usually result in a perfect match. Did you tried to import other software's scenes in pyopengl? Are they shown correctly?

I am not very familiar with rendering software and can only operate blender. The problem now is that rasterizing with pyopengl will lead to slight deformation of the rendered image, which does not fully correspond to blender. I don't know if it is related to the accuracy of the camera matrix


text:
Collection instance on point Geometry nodes
I'm beggining with the geometry node by trying to distribute collection of trees on a plane.
When i'm using the whole collection it distribute it with the original position as one object.

I tried to use the separate geometry node but the whole collection dispear.

What is the right way to get separated object from the collection on each point?
Thanks a lot !

All these checkboxes should be checked:

I just tried it doesn't do anything

@a33 In addition to the answer shown, try removing the Separate Components node. The instances are already separated as soon as you have activated Separate Children.

It fix it ! Thanks a lot !


text:
Render animation don’t start first frame
I try to render my animation but since 1 day the render automatically start at frame 1528 for no reason. When i try to render single keyframe it works perfectly fine but "Render animation" doesn't want to work from frame 0 to 1527.
When i tryed to set the animation range from 0 to 1500 blender didn't even launch no render.
I leave the .blend here if someone can spot the issue it would help me a lot !
Thanks in advance !
https://app.box.com/s/iix6xm6a8fyh3t74em2b1t38cyepua4y

You have disabled Image Sequence > Overwrite in the Output Properties, so I would guess you have already rendered frames 0 to 1527 and did not delete them before starting a new render. Good idea if you started rendering, had to pause and want to resume rendering later. Bad idea if you want to start again from the beginning. Since I do not have your drive in my computer I cannot check if the files are there, at least I can say it started rendering at frame 0 for me.


text:
Convert Hair into volume mesh or surface
I'm trying to import hair simulation in realflow to make fluid drip on it.
The problem is that i need to make the beard being a volume instead of edges or curves so i can triangulate them.
Is there a way to wrap a mesh on the beard to simulate a surface or just a way to convert the whole beard as a mesh?
Thanks a lot,
Mathieu

Clicking Convert on the particle modifier instance will convert the particles to a mesh object. Make sure you delete/hide the old particle system otherwise you'll have a duplicate floating around.

Then convert that object to a curve object.

Set the curve bevel to some small number to give it any amount of geometry, just so its not an infinitely thin curve.

Use the same previous command to convert that back into a mesh.

Then use voxel remesh to get a simple "meshified" version of the hair object.

It's highly likely that there is a better way to do this, but this is just what I managed to figure out.

i will try this i think it might work well ! thanks a lot !


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Rigid body collision not happening
I'm trying to make a simple collision between 2 chess pawn. One is animated and the other is not.

I made the basic rigid body settings but the animated pawn is just passing through the other one.
This is the setting for the animated pawn then the setting for the not animated one.

I don't understand where is the problem from..
Thanks a lot !

pls provide blend file, thx

here it is, its not in the main scene but in the scene.001 : https://we.tl/t-PRSxMmeyTK

hello, maybe make a file with only the important objects

there is only the important objects in the scene 2 of this file

@a33 Yeah, and all the objects in the other scene which makes this file unnecessary large.

You've messed up the Rigid Body World a lot, not sure what steps you did to get there but here's how you get the animation working:

Remove the Rigid Body physics from all 3 pawn objects, "Petite cailles.017", "Pied cavalier.003" and "Moto1.003" as well.
Select them all (or at least the motorcycle and its pedestal) and press Ctrl+A > Apply > Scale.
Go to Scene Properties > Rigid Body World and click on Remove Rigid Body World.

Go to the Outliner window, switch the Display Mode to Orphan Data in the dropdown menu at the top, expand Collections, select all that are called "RigidBodyWorld..." by shift-clicking on them, press X to delete them.

Now add Rigid Body physics to the pawn objects again. Remember to set the motorcycle objects back to Animated.
Go to the Scene Properties > Rigid Body World again. The End value is at default 250 again, set it back to 950. Press Delete All Bakes (this is important, although you've delete rigid bodies before, there might be a cache stored somewhere).

You could now press Bake or Bake All Dynamics or run the animation from frame 1 and the rigid body simulation would work - which in this case would mean the unanimated pawn would fall through the floor. So I suggest adding another step ;)

Enable rigid body physics on the chessboard object "Chessboard.002" as well, set it to Type > Passive.

Thank you so much you literally saved me !

I'd forgot the Orphean Data thing for reseting the rigid body world it will help for a lot of project !

@a33 Glad I could help. Would you mind considering to accept the answer then?

sorry i've forgot about that as well


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How to access Object Display properties?
I'm trying to change properties so that I map have edges drawn over the object when in object mode.
The standard google answer is to use Object->Properties->Display then click on wire etc.
There is even graphic of the display panel in the manual.
https://docs.blender.org/manual/en/dev/_images/editors_3dview_object_properties_display.png
(from page: https://docs.blender.org/manual/en/dev/editors/3dview/object/properties/display.html)
Problem is, the display panel I see is quite different.

Since the manual is for 2.78 I figure there must be a different panel that I haven't found yet.
So, looking for a clue on how to access this display panel.
If that's not available. Is there another way to have wire frame overlay the texture view when in object mode?

I suggest adding a picture of the display panel you are seeing.

This is Display rollout in the Properties shelf in the 3D Viewport, you're searching for the Display rollout in the Properties editor > Object tab. See also https://blender.stackexchange.com/questions/12213/set-all-selected-objects-to-be-displayed-as-wireframe, for multiple objects - https://blender.stackexchange.com/questions/15888/how-to-make-objects-draw-transparent-wireframe-in-the-viewport

You can change this from the Object properties as shown below:

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


text:
Can I un-hide everything without selecting everything?
I'm familiar with the Shift+H keystroke to hide everything except selected objects. When I reveal everything again with Alt+H, everything is selected, which is often troublesome, especially if I just want to quickly check how my object editing is reacting with other objects.
Is there any way to reveal all the hidden objects without also selecting them?

Yep.To hide and view anything on view port,you could just toggle the small eye like icon on the outliner. This is especially helpful when there are a lot of objects on the scene. see I have plane as well but I've toggled it off,so you cant see.You can toggle any number of items on or off to hide or view.Hope this was helpful

This doesn't actually work in 2.80 -- Shift-H hides everything except the selected object, but when you look at the outliner there is no single spot on the tree where a click will unhide the other objects.

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


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How to make an object fit in a unit cube?
In my blender object, there are hundreds of vertices, normals, faces and etc and the thing I want to do is to make it fit in a unit cube. I've tried almost everything including

Trying to find an option in file->export.
Selecting all the things using A button,
    assigning into one vertex group and
    pushing normalize all button in "Weight tools" pane.
Scaling the object somehow.
None of them works. So I need a little help. Please show me the way how to do it.

Can you explain more, I don't really understand what you are trying to do. Are you trying to scale the object, or morph the object into a cube shape?

The thing I'm trying to do right now is to scale the object in a unit cube. AFAIK, to use hundreds of wavefront obj in OpenGL, every vertices in every object should be within range of 0 to 1 to use them efficiently when it comes to managing all the objects. So I want to make every vertex within range of 0 to 1

Respecting the overall proportions, or fitting to the unit cube ?

Respecting the overall proportions.

Is that 1 object (with hundred of vertices, etc), or several objects ?

Every obj file has only one object. So 1 object.

You can use this kind of script (works with the active object) :

Alternative script, so that :

Rotation and scale are previously applied (avoid border effects when export)
Place all the vertices between 0 and 1 (previous script only matters about overall dimensions)

import bpy
from mathutils import Vector

obj = bpy.context.object

#Eventually apply transforms (comment if unwanted)
bpy.ops.object.transform_apply( rotation = True, scale = True )

minX = min( [vertex.co[0] for vertex in obj.data.vertices] )
minY = min( [vertex.co[1] for vertex in obj.data.vertices] )
minZ = min( [vertex.co[2] for vertex in obj.data.vertices] )

vMin = Vector( [minX, minY, minZ] )

maxDim = max(obj.dimensions)

if maxDim != 0:
    for v in obj.data.vertices:
        v.co -= vMin #Set all coordinates start from (0, 0, 0)
        v.co /= maxDim #Set all coordinates between 0 and 1
else:
    for v in obj.data.vertices:
        v.co -= vMin

This is exactly one I was looking for!!!

@Windforces, note that the vertices coordinates wont be between 0 and 1 here. Just the size is scaled down to 1 (like in Todd answer). So tell if it is ok.

@Windforces, edited in case of need (added a more complete script)

Just scale the object down until 2 of the scale coordinates are less than 1.0, and the third is equal to 1.0. Simple enough unless I don't understand the question properly.

Guess this would be a simple answer for my question

Do you need to do this many times? Perhaps a python script would make it easier?

I'll try to make the python script. Thanks for the advice!

@Windforces, Todd, sorry, I did not saw that before posting


text:
How to convert mesh back to text object?
I converted text to mesh now i want to convert mesh to text, how  i can do it?

I think you can't. Maybe you can undo (ctrl-z). Usually, I keep a copy (maybe hidden in a layer) of the text object that I convert to mesh, just to be able to start again from the text...

It cannot be done.  I mean, as m.ardito states, you can undo, or duplicate the text and keep a copy for backup, but converting to mesh is a one way, destructive action.

while not being able to turn it back into its original state, you can in fact grab every vertex and copy the material automatically. But you can never reside it back to its original state.
https://youtu.be/OEkrQGFqM10 should help a little
you'll probably want the vertex location command
which can be found here How can I get vertex positions from a mesh?
and basic location command is
bpy.context.object.location.x
bpy.context.object.location.y
&
bpy.context.object.location.z


text:
Why doesn't smooth "smooth completely"?
I have a plane, subdivided at 10, with sub-D modifier at 2. Smoothing is turned on. When warped as cloth, why can I still see individual polys which are bent from others at less than a 90-degree angle?

I would think not enough subdivisions in your plane. I would try more cuts than 10 depending on how large the plane is. Maybe 20 to 30.

Cloth needs a lot of subdivisions to look decent. A subsurf modifier will not satisfy this requirement because cloth sim is applied to the base mesh only. You will need to either apply the subsurf or subdivide the mesh more. Then you can place another subsurf after the cloth modifier, with smoothing on to get a smooth surface. I would suggest caching the cloth and saving your file before you apply the subsurf. It can get pretty big if you're not careful.

I added the Smooth Modifier and this did the trick. 10 subdivisions x 2 sub-surface is plenty, with the Smooth Modifier.

@Italic_  You don't need to apply the subsurf, just put it above the cloth sim in the modifier stack.


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Question about the pamameters of Arcto in sverchok's "Profile Parametric Node"
<2v rx,ry> <float rot> <int flag1> <int flag2> <2v x,y> <int num_verts> [z]

As the syntax above shows，ArcTo has 3 parameters（ float rot, int flag1 and int flag2 ） between the radius vector and the coordinate vecter.
I've found that the third(int flag2) can be used to set the direction of the arc(CW or CCW),but I can't find out what the other 2 parameters( float rot and int flag1 ) stand for and can be used to do.
It will be kind of you to tell me the answer, and thanks in advance.^_^

We (team sverchok) encourage you to use the github issue tracker to tell us which parts of our documentation are unclear. We try to cover everything but sometimes might gloss over some details like this.

This node was intended to closely resemble the SVG style of specifying paths, and you should really look at what SVG specs say about ArcTo
;; straight from the svg specs
(rx ry x-axis-rotation large-arc-flag sweep-flag x y)

For a deeper description see this github issue tracker post:
https://github.com/nortikin/sverchok/issues/350#issuecomment-51353886

Thank you very much for you answer and tip.
Maybe be I should read more issue tracker posts.


text:
draw text always face the viewer in 3D view
I'd like to write a script to draw some text in 3D view, and I need it always face the viewer, how can I achieve this?
update:
My own answer as below.

What have you got so far? Where are you stuck and what didn't work as expected?

What do you mean by blf?

Do you expect someone to write a script for you, or have you started working on one? It would be useful if you share what you have so far, and explain what precisely is giving you trouble.

@DuarteFarrajotaRamos Sorry for my unclear question, I've update it.

You should post that as an answer bellow instead, preferably with a short description of what you did wrong, and how you fixed it.

@DuarteFarrajotaRamos OK, but any clue of the documentation for types.SpaceView3D.draw_handler_add()?

No, Official info seems to be missing https://docs.blender.org/api/blender_python_api_current/bpy.types.SpaceView3D.html#bpy.types.SpaceView3D.draw_handler_add

Thank you for all of you comments, and sorry for my rough question.
But I guess I have found the answer:
I've used wrong arguement for the bpy.types.SpaceView3D.draw_handler_add() function. 'POST_PIXEL' shold be used here as the 4th argument, but 'POST_VIEW' was used. I guess 'POST_PIXEL' is for 2D text, and 'POST_VIEW' is for 3D text.
Code and screenshoot as below:
import blf
import bgl
import bpy

RED = (1.0, 0.0, 0.0)
GREEN = (0.0, 1.0, 0.0)

position_1 = (50, 50, 0)
position_2 = (0, 0, 0)

def draw(position, color):
    blf.position(0, *position)
    blf.size(0, 20, 72)
    bgl.glColor3f(*color)
    blf.draw(0, "hello,world")

_handle = bpy.types.SpaceView3D.draw_handler_add(draw, (position_1, RED), 'WINDOW', 'POST_PIXEL')
_another_handle = bpy.types.SpaceView3D.draw_handler_add(draw, (position_2, GREEN), 'WINDOW', 'POST_VIEW')

update:
I've asked someone in our community, and I was given some tips about the 3rd argument, which maybe represent for region type and enumerate in 'WINDOW', 'HEADER', 'CHANNELS', 'TEMPORARY', 'UI', 'TOOLS', 'TOOL_PROPS', 'PREVIEW'.
Code and screenshoot as below for your reference:
import blf
import bgl
import bpy

RED = (1.0, 0.0, 0.0)
GREEN = (0.0, 1.0, 0.0)
BLUE = (0.0, 0.0, 1.0)

position_1 = (0, 0, 0)

def draw(position, color, text):
    blf.position(0, *position)
    blf.size(0, 20, 72)
    bgl.glColor3f(*color)
    blf.draw(0, text)

_handle_1 = bpy.types.SpaceView3D.draw_handler_add(draw, (position_1, RED, 'WINDOW'), 'WINDOW', 'POST_PIXEL')
_handle_2 = bpy.types.SpaceView3D.draw_handler_add(draw, (position_1, GREEN, 'HEADER'), 'HEADER', 'POST_PIXEL')
_handle_3 = bpy.types.SpaceView3D.draw_handler_add(draw, ((100, 0, 0), BLUE, 'CHANNELS'), 'CHANNELS', 'POST_PIXEL')
_handle_4 = bpy.types.SpaceView3D.draw_handler_add(draw, ((250, 0, 0), RED, 'TEMPORARY'), 'TEMPORARY', 'POST_PIXEL')
_handle_5 = bpy.types.SpaceView3D.draw_handler_add(draw, (position_1, GREEN, 'UI'), 'UI', 'POST_PIXEL')
_handle_6 = bpy.types.SpaceView3D.draw_handler_add(draw, (position_1, BLUE, 'TOOLS'), 'TOOLS', 'POST_PIXEL')
_handle_7 = bpy.types.SpaceView3D.draw_handler_add(draw, (position_1, RED, 'TOOL_PROPS'), 'TOOL_PROPS', 'POST_PIXEL')
_handle_8 = bpy.types.SpaceView3D.draw_handler_add(draw, ((400, 0, 0), GREEN, 'PREVIEW'), 'PREVIEW', 'POST_PIXEL')
_handle_1 = bpy.types.SpaceView3D.draw_handler_add(draw, (position_1, RED, 'WINDOW'), 'WINDOW', 'POST_VIEW')

But I‘m still confused about the draw_handler_add funciton. I've read the api documentation for this, but is shows "Undocumented".
Anyone can help me, or explain it for me?

I'm sure you've got this figured out by now, but I think this link would be handy here.   By calling draw_handler_add you are providing the instructions which are used every time the SpaceView3D needs to be redrawn ( due to a zoom, pan, window resize etc ). The problem then becomes how to cancel these instructions.


text:
why does menu_func() in this example reference a self when it is declared outside of a class
I'm learning bpy myself, and I don't have much knowledge of python。
I read the templates in text editor to learn scripting myself, but I found some thing weird in the Operator Mesh Add template:
import bpy
import bmesh

def add_box(width, height, depth):
    """
    This function takes inputs and returns vertex and face arrays.
    no actual mesh data creation is done here.
    """

    verts = [(+1.0, +1.0, -1.0),
             (+1.0, -1.0, -1.0),
             (-1.0, -1.0, -1.0),
             (-1.0, +1.0, -1.0),
             (+1.0, +1.0, +1.0),
             (+1.0, -1.0, +1.0),
             (-1.0, -1.0, +1.0),
             (-1.0, +1.0, +1.0),
             ]

    faces = [(0, 1, 2, 3),
             (4, 7, 6, 5),
             (0, 4, 5, 1),
             (1, 5, 6, 2),
             (2, 6, 7, 3),
             (4, 0, 3, 7),
            ]

    # apply size
    for i, v in enumerate(verts):
        verts[i] = v[0] * width, v[1] * depth, v[2] * height

    return verts, faces

from bpy.props import FloatProperty, BoolProperty, FloatVectorProperty

class AddBox(bpy.types.Operator):
    """Add a simple box mesh"""
    bl_idname = "mesh.primitive_box_add"
    bl_label = "Add Box"
    bl_options = {'REGISTER', 'UNDO'}

    width = FloatProperty(
            name="Width",
            description="Box Width",
            min=0.01, max=100.0,
            default=1.0,
            )
    height = FloatProperty(
            name="Height",
            description="Box Height",
            min=0.01, max=100.0,
            default=1.0,
            )
    depth = FloatProperty(
            name="Depth",
            description="Box Depth",
            min=0.01, max=100.0,
            default=1.0,
            )

    # generic transform props
    view_align = BoolProperty(
            name="Align to View",
            default=False,
            )
    location = FloatVectorProperty(
            name="Location",
            subtype='TRANSLATION',
            )
    rotation = FloatVectorProperty(
            name="Rotation",
            subtype='EULER',
            )

    def execute(self, context):

        verts_loc, faces = add_box(self.width,
                                   self.height,
                                   self.depth,
                                   )

        mesh = bpy.data.meshes.new("Box")

        bm = bmesh.new()

        for v_co in verts_loc:
            bm.verts.new(v_co)

        bm.verts.ensure_lookup_table()
        for f_idx in faces:
            bm.faces.new([bm.verts[i] for i in f_idx])

        bm.to_mesh(mesh)
        mesh.update()

        # add the mesh as an object into the scene with this utility module
        from bpy_extras import object_utils
        object_utils.object_data_add(context, mesh, operator=self)

        return {'FINISHED'}

def menu_func(self, context):
    self.layout.operator(AddBox.bl_idname, icon='MESH_CUBE')

def register():
    bpy.utils.register_class(AddBox)
    bpy.types.INFO_MT_mesh_add.append(menu_func)

def unregister():
    bpy.utils.unregister_class(AddBox)
    bpy.types.INFO_MT_mesh_add.remove(menu_func)

if __name__ == "__main__":
    register()

    # test call
    bpy.ops.mesh.primitive_box_add()

self is used outside class indef menu_func(self, context):.
I was taught that self can only be used inside a class, so I'm confused.
Anyone can help me?

The answer lies in what happens in the register function, below the menu_func:
def register():
    bpy.utils.register_class(AddBox)
    bpy.types.INFO_MT_mesh_add.append(menu_func) # <<< This is the interesting bit

As you can see here, the menu_func is appended to the INFO_MT_mesh_add type as a new method. INFO_MT_mesh_add is the Add Mesh Menu in the blender UI.
This is the class where you will be adding the menu_func to, not the add_box operator.
This function is added to the Add Mesh Menu, and when you call it from the blender UI, it will be executed like any method. That means that it will get the class instance as the function's first parameter, "self".
The word "self" has no real meaning by itself, and is merely the first parameter this function receives. It is a convention in python (and some other languages) to call it "self", but you could call it "james" and it would work just fine.
When the function is a method in a class, it automatically gets the instance of the class as the first parameter when called from the instance (or the class itself if its a @classmethod, in which case we usually call the first parameter cls instead of self).
class someClass:
    def myMethod( self ):
        print( "I get the class instance as my first param 'self'" )
        print( self )

clsInstance = someClass()
clsInstance.myMethod() # myMethod will get clsInstance as the first parameter

We could write it this way though, and it would work just the same:
def to_be_method( self ):
    print( "I get the class instance as my first param 'self'" )
    print( self )

class someClass:
    # Reference to_be_method as our class' own myMethod
    myMethod = to_be_method

clsInstance = someClass()
clsInstance.myMethod() # myMethod will get clsInstance as the first parameter

So as you can see in the example above, we define a function outside the class and used the "self" parameter, and then referenced this function inside the class.
Appending the menu_func into the INFO_MT_mesh_add class does something similar, which is why it's fine and works well.
I hope this explains the situation rather than confuse you even more! :)

The self argument in menu_func(self, context) could also have been written as:
def menu_func(caller, context):
    caller.layout.operator(AddBox.bl_idname, icon='MESH_CUBE')

The fact that it is written as self is a choice and a convention. The name isn't as important as the position of the arguments and the number of arguments in that function. Using self, context helps you and others see that it is being called from another place that does have a self and context.
Why a menu_func at all?
Using a function like menu_func() allows us to describe a portion of the layout from our own add-on. If you couldn't specify it externally you would be forced to always edit your menu additions to INFO_MT_mesh_add manually, and each time you upgrade to a new version of Blender.
prepend(menu_func) vs  append(menu_func)
Let's say the draw function of INFO_MT_mesh_add looks like this:
def draw(self, context):
    layout = self.layout

    # menu_func is called here if you used INFO_MT_mesh_add.prepend(menu_func)
    # in the registration function

    ...existing menu items ...

    # menu_func is called here if you used INFO_MT_mesh_add.append(menu_func)

For example if you use .append, you'll get your item at the end of the   draw function, you might imagine that the code that python executed is equivalent to
def draw(self, context):
    layout = self.layout

    ...existing menu items ...

    menu_func(self, context)

That means inside the draw function, the function menu_func is called with the self and context available to the drawing function at the time of calling.


text:
Render time problem on character animation
When I woke up this morning I opened my last project but I started to want to render an image containing my animated character, rendering became extremely long or even impossible. Yesterday I did not have this problem while I did not modify it.
I'm sure the problem comes from the character because when I hide it the problem no longer occurs.
I don't understand but maybe one of you can help me...
I attach the .blend right here: https://app.box.com/s/peg6wb0l4h3q5bhwheih9d8xa4tyfnf1
Thanks in advance !
PS: I'm using 3.0

It seems like the problem is not happening when i disable the Motion Blur.
The fact that it is due to the character and the motion blur, i think the reason is coming from an not wanted movement from something in the character that the motion blur is not able to calculate or to understand.
If someone knows..

I've also seen that sometimes rendering time gets crazy when the movement of an object is not continuous and jump from a position to a completely different one (motion blur doesn't understand).
The problem is that it doesn't happen in my animation so perhaps there is a bug in a vertex or armature animation...


text:
Is there a way to make an animated procedural texture loop seamlessly?
After following some tutorials online I've made a basic texture from overlayed noises that scrolls up a shape on the Z axis, like fire.
I've noticed that the texture will go on forever, which would be fine if I were making an animation, but I was hoping for this to loop seamlessly, so that I could then somehow export it as a series of images for use in an old game (which is limited to flipbook style sprite sheets rather than fancy shaders etc.)
Is there some way to make Blender limit the generated texture so that it will loop how I wish it to? (while being able to specify the speed etc.)
And while not strictly Blender related - if not, is anyone aware of another program which can create procedural textures similar to Blender, that can be looped seamlessly and exported as frame-by-frame textures/sprite sheets?
Many thanks for any assistance!

May be relevant: https://blender.stackexchange.com/a/195316/35559

In my example the noise texture gets duplicated (they have to be identical).
Noise A: its mapping Z loc is animated from 0 to 1.
Noise B: its mapping Z loc is animated from -1 to 0.
Mix factor is animated from 0 to 1.
All animations have to be interpolated in a linear way (select all on Dopesheet, right click > Interpolation > Linear).

.

This also can be interesting https://www.youtube.com/watch?v=GbkFn2yaOgg

Just wanted to mention, of course if someone wanted the animation to slow down and speed up etc. one could still use Bézier interpolation, might not look as seamless from its motion, but with your setup it is still seamless regarding the procedural texture. Without this kind of mixing the first and last frame would have different textures and there would be a jump visible in the noise.

Thank you for your response! Unfortunately, this did not give me the effect I was hoping for; as mentioned in my question, it is necessary for the texture to move only on the Z axis, upwards, like fire. With this node set up, the texture appears to move up and down rather than scroll upwards on the z axis in a seamless loop =/

If you copy my setup, which is different from that in the video, it's possible to get the scroll upwards as requested.

Hey Josh, sorry for the confusion; the comment was directed at yourself. I tried the set up in your image, but the result isn't a seamless loop in a single direction: half way through the animation, the texture changes direction from upwards on the Z-axis to downwards on the Z-axis. From beginning to end, this gives it a kind of bouncing effect between the top and bottom of the mesh it's applied to.

It means that there are wrong values in keyframing. Try top texture Z from 0 to -1, and bottom from 1 to 0.

That's done it! Yeah, rather than -1 to 0, the second node had to be 1 to 0. Thank you for your help!


text:
how to get rid of these weird black mesh patches on my donut icing?
so, i am following a youtube tutorial of how to make the donut and i followed the exact same steps.. i repeated the whole process 3 times to make sure i am not doing any mistake but still these black mesh patches do not go away. i am a beginner and this is the first time i am using blender. please help me.These appear only while moving or rotating the donut And also i already solidified the icing but it does not go(but it reduced little but still there). i will attach the image:

you probably have 2 donut objects overlapping

Looks like your icing is overlapping the donut. Select it and move it up a little bit and it should disappear.

Yes, I think the icing is overlapping with the donut or maybe there is a duplicate object overlapping the main one.


text:
Can see through strokes in blender grease pencil
For some reason I can see through my grease pencil strokes and fills. How do i stop this.

Please clarify your specific problem or provide additional details to highlight exactly what you need. As it's currently written, it's hard to tell exactly what you're asking.

this video helped me with these kinds of things:
https://www.youtube.com/watch?v=VE1IRA-OgcQ

The stroke here is clearly not cyclic, so filling would probably not occur here.
It would help if you showed a screenshot of your material settings, because chances are, the fill color is also transparent.
Go into the stroke properties tab, enable cyclic on the current stroke, and check that the material fill color is opaque to some degree.

You need change Stroke Depth Order from 2D Layers to 3D Layers:


text:
Movement/transform gizmo isn't "flat"
I'm a complete newbie to Blender and have been following a couple tutorials about viewmodel animation. An issue I've run into though is that when I select anything, be it a model or a part of an armature or a bone or whatever, the movement gizmo is not positioned correctly.  I have no idea when this happened or why, and I don't know what kind of question to search to find a solution. Help/guidance is much appreciated!

Please clarify your specific problem or provide additional details to highlight exactly what you need. As it's currently written, it's hard to tell exactly what you're asking.

To add some clarity: I have everything set to global position, so I don't know why it's askew. I genuinely don't know how else to describe this situation.

Still looking for help.

could you please share your file? upload and copy paste the URL it will give: https://pasteall.org/blend/

https://pasteall.org/blend/1624509f058d4f72a40b14a078fa2b35 Here you go moonboots

@moonboots sorry to ping but I forgot to in my previous comment. I'm still having this issue and still haven't found a solution.

You've disabled the Header > Show Tool Settings option of your header menu, which is currently at the bottom of your 3D view, right click on the header menu to display this pop-up then choose Header and enable the Show Tool Settings option:

Now you can see some additional functions, like this Orientation dropdown panel, it overrides the orientation you've selected in the Transform Orientation panel, choose Default instead of Cursor:

Thank you, this fixed it!


text:
object mode, can not cancel select
I'm in object mode in blender 2.81, and I select 1 object, and then I click on empty area, it does not cancel the selection, I can not drag mouse to select multiple objects.

Can you add a screenshot? Perhaps you've accidentally changed some configuration that causes this behavior.

You may have disabled Meshes in the View Object Types menu.

Or less likely might be in tweaks mode, click and hold the mouse to change back to box select.


text:
Need help Animating water
So I am trying to animate some tectonic plates for my geology class and I want to make the water fall as the plate moves  and then go back up, creating some sort of waterfall loop, but I dont want it to spill to the sides. Any ideas of how I can do It?

If I understand the question, this is fairly easy to do.  In Blender 2.79-2.81 you need three different types of features for water.  These are all selectable in the physics tab under the fluid button.  You need the Domain of the problem which limits where the blender physics engine calculates the water interactions.  This needs to be a rectangular block.  Then you need your water (the ocean in your case) which can be larger than the domain, but only that part in the domain will be animated.  Then you need a fluid obstacle which in your case are the tectonic plates.  When you run the simulation by hitting 'bake' the water will not flow out of the domain unless you put a drain or an outflow in it. You can put an outflow between the plates and set it to drain only when the plates pull apart.
Hope this helps.

It wouls be useful to link to the official blender docs for fluid simulation.  Also this doesn't really solve the problem as the domain must completely enclose all participants in the fluid simulation.  Please read [answer].

Merlin, I fail to see how your point is relevant in this case. I did some further tests. and as I stated, the domain does not have to completely enclose the water, but only that fluid that is in the domain is involved in the calculations.  You were correct that the obstacles  have to be completely in the domain to affect the fluid, but this doesn't change the answer.  Also I typically find the documentation to be: Out of date, inscrutable, incomplete, or just missing.  My first stop is always YouTube and only if I can't find an answer there do I look for docs. If not there, then I ask here. :)

Actually the fluid sim documentation is a) a primary resource and b) actually quite good, thorough and up to date.  It's a shame you don't think it is relevant.  Also the domain doesn't need to be a rectangular block, it is defined by the bounding box of the domain object.

That's good to know about the documentation. I'll check it out.  Though hopefully the new Manta Flow build will be ready soon.

I've always been curious about that and the  Flip Fluids addon.  So little time to play with these things sadly.

To fake the water surface rather than to simulate it, an animated Noise texture used as bump on a Glass shader could be used, in particular when you don’t want to simulate spectacular tsunamis. Some hints can be taken from How to animate small water surfaces in structures?.
There is also the Ocean modifier (see various tutorials).


text:
Just getting started, what hardware?
I am just getting stared in Blender and am enjoying the heck out of it so far.
I have two systems I could work from and I'm trying to determine which would be better

A 2.5Ghz i5 four core laptop with a 1060
Ryzen 5 3.7Ghz four core / 8 thread with a Vega 11.

I honestly don't yet know much about 3D modeling and assumed that the system with the better GPU would render faster.
I loaded a few test scenes on each system and did a casual comparison and was surprised to see the  RYZEN system pull way ahead on my first test.  However the next scene I rendered favored the Intel system.  Over several scenes it varied back and forth.
So can the individual scene render better on one type of hardware than the other?  If not, which system should be better?

well if you are into sculpting or complex scenes, choose Ryzen.
If you are into asset creation, you need that dedicated GPU! first one would be nice for that.
If you are into rendering, I would not advice you to do night long scene renders on a laptop! so none of them!!

The 2nd system would be better at rendering only using the CPU, but the 1st system would be better at rendering with CPU + GPU combined, along with running EEVEE better, since it uses a dedicated GPU. I'd suggest the 1st system, since the GPU should be able to pick up the slack of the weaker CPU, though you'll have to go into Blender's settings to enable Blender to use the GPU at all. (Also the fact that rendering with only GPU is faster than rendering with only CPU. Still turn both on though.)
Go to Preferences > System and tick off both CPU and GPU to enable this.


text:
Object not rendering/Object teleporting. Blender 2.8
I created this Sci-Fi thing and the ships (which I made in a different blender project) are not rendering. I can't find anything that can help me. I am using Blender 2.8.

This is the render: Google photos link to large render output
Also, when I load the save, all of the ships go to the middle where you can't see them, which makes it look like the final render. So the issue might be that the ships keep teleporting to the middle.

How to upload an image to a post

@DuarteFarrajotaRamos I tried to fix it but the image is too large.  Going to leave it to the OP to sort out, but tidied up as best I could

Just fixed it. There was an animation on the ships. I deleted them and everything was working. Thanks for the help.


text:
How to make "Weight Paint" affect all vertices, even those with zero weight?
There is something that I can't understand about the "Weight Paint".
I was testing some stuff with a few Models, I need to decimate and fix this one for VRchat, but how does the original model rotating all parts so smoothly?
For example, when I rotate the Head bone of the Original upwards, the head looks nice and it seems to stretch all vertices nearby even if the weight of those are "0". That gives is a smooth look.
When trying that on my version of model with an almost self-made Rig, it only affects the vertices that are painted.  This deforms my model in an unexpected way.
I made 2 screenshots for an example:
Original

My version

Why does the head of the original affect all those vertices on the neck with 0 weight and stretch them slightly, while on my version its just pulling on the painted ones?

A smooth deformation of a bunch of vertices is always due to a balancing between 2 or more different weight assignements: if a vertex is weighted to a vertex group only, it will move with its relative bone rigidly and exactly, even if the weight is 0.00000001. Instead, if it has some weight relatively to two (or more) vertex groups, the movement is calculated making a comparision between the two values, with an automatic normalization; normalisation means that if one value is 0.001 and the other is 0.009, they are treated as 0.1 and 0.9 and their sum will be treated as 1.0.
So it's importany to analyze all weights, in your case not only head bone but neck bone also. If you select a weighted vertex in edit mode, you will find in the "N" properties panel a "vertex weights" tab in which you can inspect all weights and have a better understanding of the behaviour.
To solve your problem you will have to give some weight to the neck vertex group, so that vertices near the neck will be pushed to two different actions: the head bone will try to move them while the neck bone will try to make them stay in place.
Image is 2.79 but 2.81 is the same.


text:
How to access data related to individual particles?
I would like to create simple drivers to manipulate individual data points for things like Particles and Array Modifiers.
Just as an example, when I create a particle system, if I create a driver for the Size parameter, it changes the size of all the particles simultaneously (as it should).  But I would instead like to access the size for each individual particle.
For something like an array modifier, I would like to access the data paths for each instance.  For example, add a randomized driver to create different iterations of the original mesh.
Are either of these examples possible?

While we can read particle data, we can't alter it. See my response here. I expect animation nodes will be your solution.

@sambler - Thanks.  Are you saying that animation nodes could accomplish the same thing?  For example, with particles, I want to have the particles generate get larger over time... but all the particles should keep their size throughout the simulation.

Animation nodes can duplicate an object and place it at the location of each particle, you can then calculate the size and rotation of each instance which can include the frame number in the calculation. Actually this answer should get you started.

As Sambler said, Animation Nodes is your best option. Here are some examples:
Controlling the size of individual particles based on time (They get bigger as time passes):

Controlling the rotation of individual particles based on a random vector.

Wiggling the size of instances cube:

+1 - Quick question: In the first example, just looking at one individual particle, will the particle keep the same size throughout the simulation?  Never used animation nodes before, but it looks like each particle would continue to scale with animation length.

@bertmoog That is true, current node tree will make it keep scaling. But you can just make it fixed. Tell me exactly what you need and I will provide an example.


text:
A quick way to merge all object while keeping all extra data and modifiers?
I was trying to export model I made to the game engine, but it was made of a lot of smaller object, so I wanted to merge them before doing so.
The issue is.. something always breaks when I do so.
-If I use Boolean to merge them - vertex groups get lost, and so is the skinning.
-If I apply all the modifiers, join everything with Ctrl + J, then apply Armature modifier again - normal transfer I did in separate objects get lost. Setting them up again may work, but there are a lot of them and they all have masks, so doing it everything by hand each time I want to export the model will take too much time.
Is there some good way to do so?

The only way to do this would be to have all the modifiers applied on the final merged mesh, with Vertex Groups to turn them on and off on different areas. Not only is this not practical, it's costly and not possible for every modifier.
You shouldn't need to merge your meshes when exporting, the exporter should be able to apply everything and merge according to the settings you chose

I see. What format exporter can do this? I'm using FBX now, but I didn't see any "merge" options there. And Unity's importer go no merge options as well.

follow up as answer for the convenience of image:

This is the settings for the fbx exporter, when you're choosing the file name.
There are no specificially merge options because the process of exporting will merge everything set to be exported. You can limit this with the Selected Objects and Active Collection switches.
You also have a switch for the application of your modifiers.

Hmm? It does not really merge everything - it does apply modifiers, but when I import mesh in Unity - I still have separate objects for each object I had in Blender. And yes, I can select what I export with those options you mentioned, and I used them.

do you have them under the same collection ?

I have all them in single collection, then some of they are in different sub-collections. I tried moving them all in single one and exported, but it changed nothing.


text:
Why is my hair flat?
I am having an issue getting my hair particle system to show up in object or render mode. Attach below I provided pictures to help with the explination. I have already combed and puffed the hair particles to my liking in particle edit mode however, when I return to object mode or render the image my hair particles dissappear and show as it they are flat against the models head. All except the front hair line particles which are standing straight up? All of the particles are on the same system so I don't understand why part of them are acting one way while the rest act another? I've tried everything the internet has giving me and I'm still as a loss. Please help me figure out why my hair isn't hair. enter image description here

I finally figured out it was the hair dynamic setting. I never did figure out which specific setting in hair dynamics was causing it but when I simply turn off hair dynamics it fixes the issue.


text:
How do I get my UV islands to be symmetrical? Why is my unwrap asymmetrical?

I've checked that the model itself is actually symmetrical. I even deleted half then mirrored and applied to make sure and the face still comes out crooked in the unwrap.


text:
Volumetric Shade coming out ultra low resolusion
any ideas why my Volumetric shader is doing this to the monkey? Thanks a lot :)!

Just seeing that this is an evee vs cycles thing. Is it possible to get decent fog details in evee?

Well, you didn't show your settings, but generally speaking you can get more details by using a smaller Tile Size and more Samples in the Render Properties > Volumetrics options. However this won't change the volume to match the shape of Suzanne. Quoting from the Blender manual about Eevee Limitiations: "Volume Objects - Object volume shaders will affect the whole bounding box of the object. The shape of the volume must be adjusted using procedural texturing inside the shader." So in Eevee the volumetrics always have the cuboid shape of the bounding box (where density > 0).


text:
UV Texturing has unwanted seams
I have this problem where if I apply an image texture it gets oddly distorted or doesn't line up. I can't seem to figure out what I am doing wrong.
Here are 2 images showing what I mean.

How to upload an image to a post

we don't know enough about your image or UV map, please show some screenshots or pack the image and share your file here: https://blend-exchange.giantcowfilms.com/


text:
How can I hang an object on a rope or cloth simulation
I have created a spider's web with cloth simulation, which works well.
I now want to hang objects on this web and simulate the weight of these objects acting upon it.
How can I pin objects to some vertices in the cloth simulation and make the web interact with instances of falling or pinned objects?

As no one could give a complete answer yet, I'll show you an easy hack/workaround that maybe is sufficient to solve your problem:
In my example I have filpped the plane, put it over the cube, made the cube a collision object, made the plane an unpinned cloth, let the cloth fall on the cube and wrap around it, found a keyframe in which the deformation was good, apply it as shape key, rotated back the plane so that the deformation was toward the bottom.
Then I animated the cube with 3 keyframes only: the start, the contact and the bouncing end; turned the second keyframe's interpolation form Beziers to bouncing, adjusted the values.
Then I went to the plane's shape key, set its max to 2 and min to -1, so tho have room for deformations in both directions, set manually a keyframe over every max and minimum of the bouncin curve, adjusted the curve in graph editor (there is more room to further adjust, but I think  it's enough for the tut purposes).
Ten minutes bouncin!

Thank you very much.
But to hang an object at a cloth simulation is not possible?

I don't know :)


text:
my picture is just grey and white
I loaded a file and the 3d model is white. I looked at different hoping to find a preset that will give the model color but I couldn't find it.
I then went to UV/editing to put an image in, but there was no color either.

It looks like you haven't added a material to your model. You need to add a material, create an image texture node referencing your texture, and connect it to the base_color of the Principled BSDF that appears.
The material can be added by clicking on the +New button above the shader editor (while the mesh is selected), or in the materials tab of the properties panel (on the right, its icon looks like a checkered sphere). You can add the image texture node by pressing shift-a and choosing texture>image texture.
If you want a shadeless texture in EEVEE, use the Emission BSDF node from the shift-a>shader menu.

Image textures needs UV Unwrapped Object.
You have to UV unwrap it first!
Select the object an switch to Edit Mode.
Press U and unwrap it!

Now you have to adjust faces in UV Editor for desired result.
For more about UV Mapping refer this, this or this

UV Mapping only works in Edit Mode


text:
How to make better looking lights/lightbulbs
Just throwing an emission shader just yields a completely solid light, which i don't want. Throwing a glass-like shader on a bulb made around a light (via emission) basically just shows the light and the glass would be nearly invisible.
Not like this:

Something like this:

(The brighter bulb, on the right)

welcome to [blender.se], please note that there are formatting tools to import images from imgur.  It is important to properly format your question in order to entice others to answer it.

Try to look, whre does the lightbulb really emit light and model this part, and make the outer part really out of glass. Try to do verything like it looks in a real lightbulb and then tweak your values until youre happy. Except they are in a far distance, then you might just use an light source in form of  bulb in purpose of shorter render times.

Edison bulbs have tungsten filament in them that's how they emit orangey light while heated.
Model that filament and set that as an emission object. You can insert the filament's temperature in blackbody shader and give that as a input for color of your emission shader of heated filament.
You can use glass shader for outer body, but it will cost higher for render times, so i recommend you to make a fake glass shader.you can search that on internet.
If you don't want to make it then you can enable cycles material library addon and import fake glass node group. This addon comes inbuilt with blender.
If you are using eevee, mesh lighting would not work. So you will have to place a point lamp near filament and set the same colour as filament.
The emission shader of filament will not be able to lighten up other objects in eevee. But turn on the bloom and you will be able to see it glow because of the emission shader


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How to get a pixelated image?
I'm trying to make an animated pixel art sprite. I can render it no problem at its normal size settings, but when I set the image size extremely low, it doesn't come out like it should in avi jpeg form. When I render the sprite at its full resolution, it looks like this:
I tried to pixelate it by setting the resolution extremely low, and got this:
That's what I want. I want the image to be pixelated, but when I export the full animation as an avi jpeg video, it completely blurs the image beyond all recognition because it's such a small image. This is what the output looks like:
How do I render / export / format / scale the image such that I will get a sharp, clean pixel animation, with every frame looking like the second picture?

Not sure where a setting is or what codecs work with this, but the term I think you are looking for is "interpolation", you want that off.  What program are you viewing the exported animation in?  It could be that program just smooths the image to whatever scale.

@root Does blender support a format that doesn't compress and supports alpha?

@root would the best way to add an alpha masked sprite to a program like Unity be to render a series of PNG images instead?

related: What is the relation between the scale nodes that includes the pixlate node?

You can use a Pixelate node in the compositor. Go to the Compositing Screen Layout or open a Node Editor some other way. Make sure the Compositing Nodes button is selected.

Use the following setup. Notice how the left side of the gun is pixelated, but the right side is normal. In the final render, it will all be pixelated. Additionally, see how the both Scale node's X and Y values are equal. Also notice how between them they equal 1 (0.2 x 5 = 1). This means that the overall scale of the gun image doesn't change.

If you so desire, you can copy the node setup straight from the following file (gun not included) (sorry) (it does include an awesome hippie monkey, tho). Lastly, you can read more about the Pixelate node here.

Pixelated:

Normal:


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A way to get Rate of Change in translation or rotation into a shader node
I am doing a space scene with a space ship, and i'm trying to be physically realistic when it comes to how ships move in space.  As such, I only want my thruster effects to fire when the Rate of Change of rotation or translation is changing.  I could animate it all by hand, but I don't want to if I don't have to.
Is there an input node I can get this information with?  Everything i've seen is just plain location data.  Oris there an addon or script I haven't been able to find?  Can this information even be retrieved with a script and i'm up a creek?

Its possible to control nodes values with drivers, did you try that?

@Denis Thanks for that, I hadn't thought of using those in that way.  I was stuck trying to do it only in the nodes.  I can drive a shader value off my rotation and translation info, but not the rate of change of that info.  At least, not that I can see.

You can achieve this by considering the F-Curve values in the graph editor. If the change in curve evaluation values between two neighboring time steps is greater than that between the previous time step neighbors, you have acceleration. I'm on mobile now so I can't test how to make this work with the node editor, but I'm sure there is a way. Will post an answer if I can make it work once I reach my computer.

@UlfAslak There is no way to evaluate an F-Curve at specific frame in driver, because that requires non-build-in function on that curve. This can be done with pydrivers. They don't update right on nodes though (dependencies issue) so when scripting its better to script this with frame change handlers.

Apparently both answers doesn't solve your issue. Please let us know what else you need.

Sorry, didn't know I needed to check a checkmark.  Thanks for pinging me on this.

Blender doesn't give value changes off the sleeve. What you need is to evaluate an animation (F-Curve) in current and previous frames and compute the difference. This solution uses a script that adds a custom frame change handler. Other way could be with PyDrivers or using Animation Nodes plugin.
Run this, it will add new properties to objects and it will update them every frame. You can access them in driver:
import bpy
from mathutils import Vector, Euler

curr_frame = None

def frame_handler(scn):
    global curr_frame
    if curr_frame != scn.frame_current:
        curr_frame = scn.frame_current
        for obj in scn.objects:
            obj.speed = (obj.matrix_world.translation - Vector(obj.last_loc)).length
            last_quat = Euler(obj.last_rot).to_quaternion()
            quat = obj.rotation_euler.to_quaternion()
            obj.angular_speed = quat.rotation_difference(last_quat).angle
            obj.last_loc = obj.matrix_world.translation
            obj.last_rot = obj.rotation_euler

bpy.types.Object.last_loc = bpy.props.FloatVectorProperty()
bpy.types.Object.last_rot = bpy.props.FloatVectorProperty()

bpy.types.Object.speed = bpy.props.FloatProperty()
bpy.types.Object.angular_speed = bpy.props.FloatProperty()

if frame_handler not in bpy.app.handlers.frame_change_pre:
    bpy.app.handlers.frame_change_pre.append(frame_handler)

Added props of interest are:

speed (in blender units per frame)
angular_speed (in rads per frame)

Use them in driver like this:

Here I am driving Y-scale and view-port material color with speed:

Note: this will only work when playing the frames sequentially. If you jump around you will get crazy values. This is a very simple handler using values from last and current frame, but it could be adjusted to read from the Fcurves of objects if you need.
Also it expects rotations in euler, but it transforms it to quaternions anyway. So if you want quaternions no problem.

This a pretty awesome solution! Addressing your comment to my comment, you can get the F-Curve value at every frame, so my clever idea was to write a script that evaluates the acceleration at each frame using this property and then somehow implement it as a node that would output a value between 0 and 1, to be routed into e.g. a mix shader in the node editor. Didn't get that far in the process, and your solution seems to be working pretty great, so cheers!

@UlfAslak Oh I meant you cannot get the Fcurve value with driver native functions. With scripting (PyDrivers, OSL script nodes, etc.) the possibilities are indeed endless.

@Jerryno too bad it can't be done directly with the drivers, but this solution is neat!

You could also play with Animation Nodes Addon by using Location Velocity and Rotation Velocity values of the Object Info Node. Following example uses translation velocity values to drive the strength value of an emission shader:

Test rendering of a simple sphere animation

Create an Object Info Node,
Split the velocity values (x,y,z) into single ones by the help of a Seperate Vector Node,
Add Math Nodes to calculate the sum of the x,y,z velocity and
Add a Cycles Material Output Node to plug the result into a shader value:

Scene Setup (click to enlarge)
This example is just an idea, things like combining Location Velocity and Rotation Velocity values or creating a color by these values are also possible with simple math, of course.

Preview Scene (click to enlarge)

I don't see Object Info node anymore, do you know what node to use instead in latest version?

@Neil unfortunately Velocity sockets have been removed in latest versions, see: http://blender.stackexchange.com/questions/44556/there-is-no-object-info-node-in-animation-nodes-addon I'll update the answer as soon as possible.

Using Animation Nodes, you can compute the velocity of an object based on the F-Curves of its animation as described in this answer. You can then pass that velocity to Cycles in a form of vertex color map per object using the Set Vertex Color node.

To calculate velocity, you need to know where the object is (which is easy with Animation Nodes) and where the object was (which is harder!).
Here's a slightly hacky little trick that works in Blender 2.8. It uses Python to store data from the previous frame, which you can then use in your simulation. This only works when playing the frames in order, if you jump around on the timeline it won't evaluate correctly without some additional stuff.
This approach is a much-simplified version of that suggested in Omar's excellent answer here: How to store particle locations in a list?
The process is as follows:

Important: set Auto Execution to Frame Changed only.
Read the data from the previous frame - in this case a Vector3D storing location XYZ. This is done with the node labelled 'Read Data', which is an expression node set to animation_nodes.previousTransformValue
Do whatever you want with the stored value. In this case, wejust set the sphere to the cube's previous position using an Object Transforms Output.
Read the new transformation data (with the Object Transforms Input).
Overwrite the temporary data with the current frame's data. This is done with another expression node, labelled Write Data, with the expression animation_nodes.previousTransformValue=[newTransformValue, dummyInput][0]. It has two inputs, newTransformValue (a Vector3D with the new location data) and dummyInput, an Object Input. Dummy Input actually isn't used in the calculation, but having it connected forces the nodes to evaluate in the correct order. If we left that out, we might end up writing over the data before we'd used it in our calculations, which would leave us with the current frame's value instead of the previous frame's!

Note:
This approach only works when frames are playing sequentially, and will be incorrect on the very first frame. You could add extra data which specifies what frame the data is from, and then initialize the data to a known value if the data is from the wrong frame, but the simpler option is just to start playback one frame earlier.


text:
object animation / keyframe moving wrong object?
I'm animating a sliding door. I have two window panes and one frame.  They are not parented to each other and I have separated them from a single object. It is three total objects.  I cleared all location, applied locations to all three as well.
However, when I add a location keyframe to just ONE door to swing open, the whole frame moves along with that door object. I did NOT keyframe the frame object. Why are these other objects moving when I specifically key framed a totally different object for location change?
I have uploaded my blend file to google drive:
https://drive.google.com/file/d/0BzM6QGd0jb8YU0hiUTRVMS1BVmc/view?usp=sharing
The sliding door model is on layer 2 and i have attempted to make an animation in dope sheet called "sliding_door_open".  All I do is grab the left door, move it -2 direction on the X axis and insert location key frame, etc.

Have you checked the animation curves after selecting all objects, and also constraints or hooks on those objects? If you can't sort it out checking most common places, nobody can't help you without having the file, I guess.

I have checked those things and still not sure why. I have uploaded a link to the .blend file.

In that file, I see only one door sliding... as expected. ?

I'm unable to make both doors swing.. everytime i add keyframes the whole frame moves or other "wierdness" happens

ok, but is not clear what you wish to achieve: there are 2 doors. should they slide  together in opposite directions, so to free the door passage? Or how?

Yes should slide opposite... freeing the passage like regular sliding doors you see everywhere

Ok, I'll write an answer so to be able to attach images and files.
As I wrote in the comments above, I tried your file and it just is wrongly keyframed, it has no other weird problems, to me.
What you have to do is reset the keyframes for the two sliding doors, and I'll show you how, below.
Your file hase several shapes, so I created a new empty blender file, and then just imported (appended) the three relevant objects from your file (cube.003, cube.004, cube.005), and since also their existing keyframes were imported, I use this as a starting point to reset animation for the sliding doors, as desired. But you should be able to use your file (I tried and it works also there).
This is what I imported (appended) from your file: there is a keyframe for the left door but is moving in the wrong direction (it goes to the right)

To restart from scratch, first I've deleted all existing keyframes for the door setup:

Then, at frame 1 I selected both doors, and inserted a keyframe there, for the starting position

This is what you get after (I also moved to frame 21)

Then I selected the left door and moved it X -2

And moved the right door to X +2

This is the desired final position, at the frame 21 so, let's add a keyframe for both selected doors:

The result is shown in the f-curve editor:

I'll add the file here for your reference:

Let me know if there something that needs to be explained more.

Thank you for the great explanation above! Do these animations go to the same animation action in action editor if I need to export them in, lets say fbx format or something?


text:
Flame in an animation
I have been trying to get fire on an "Ark of the Covenant" for months.  It shows that it is there when I run the Timeline playing the frames.  I set everything up in the node editor, exactly as the tutorials say.  But the flame still will not animate.  I don't use GPU.
Does anyone know how to solve this problem.
Thank you very much.

Welcome to the site, what are your simulation settings? Node setup? We need more information than "exactly as the tutorials say". You can edit any new information and screenshots into your question.

I think you need to "bake your simulation"
It sounds like you are recalculating it every single time you play it
and your computer isnt fast enough to calculate the animation in real time
But if you bake it, it will save the calculations so it wont have to
re-calculate it all the time.
https://www.blender.org/manual/physics/smoke/baking.html


text:
Procedural texture on moving hair particles
I have hair particles with procedural texture on it. When I animate the particles, texture does´t move with them and this looks odd.
How could I make texture move with hair particles? Is it possible?

The base of the hair doesn't move so why would the texture?


text:
Way of seeing data as image anywhere in a Cycles nodes setup?
I made a complicated nodes setup for a material using Cycles.  Is there an easy simple way to peek at the data passing through any node, to view it as an image?  I desire something like an oscilloscope, where I can touch a probe to any point of the circuit and see what kind of signal is there.
In Blender Internal, I could make many Output nodes and hook them up anywhere, and they'd show the data as a texture on a sphere, cube, Suzanne or whatever.  There doesn't seem to be anything like this for Cycles nodes.
Example of using Output to monitor textures along the "circutry".  (This is not any sensible texture; just messing around with BI nodes.)

maybe you could share an image of one such BI node setup?

Plug it into the output node? There isn't really a viewer node or anything like that in cycles.

Personally, I use a temporary Emission shader and connect it to whatever I want to look at. I also have a small viewport render open almost permanently.
The emission shader renders really quickly taking only a couple samples to converge, so it's nearly instantaneous, especially if you go into local view (Numpad /).
I've recently released an add-on that uses this method, but sets it all up for you so you simply have to Ctrl+Shift+Left Click a node to view it's result (just like the compositor).

[Update: The Node Wrangler add-on mentioned is included in Blender now, simply enable it in your user preferences]

Whether you use an emission or just a diffuse you can input a colour from anywhere in your node setup and send it straight to the material output. One thing we don't have is a shortcut to connect to material output like we do with the composite viewer node. But then material node setups are generally smaller than composite nodes so wiring a node to the output isn't as hard.

I've actually added a feature to the Node Efficiency Tools addon that makes/connects the Emission node using a hotkey, so it acts exactly like the Viewer node in the Compositor. I'm waiting for Bartek to check it out, but you can still download my version of the addon from my comment at the bottom here: https://projects.blender.org/tracker/index.php?func=detail&aid=33543&group_id=153&atid=469

Protip: Set that small viewport to local view with the emission shader only (or its own layer, but that pollutes) and it'll eat up less computing power.

Just to note, you can go into local view by pressing / on the numpad.

Use Node Wrangler add-on.
It's delivered with each copy of Blender.
Go to Main Menu > User Preferences > Add-ons > Search "Node" and enable "Node Wrangler" add-on.
Then you can Ctrl+Shift click on any node and it'll be automatically connected in such a way so you can see what is coming out of each the node, and how is it contributing to the material.
I also advise you to read Node Wrangler's documentation, because it does much more cool things that ease up working with nodes:
https://wiki.blender.org/index.php/Extensions:2.6/Py/Scripts/Nodes/Nodes_Efficiency_Tools

That's what Greg Zaal said a few years ago ; )

There is currently no way to do exactly this is cycles, but you could arrange your screen in such a way as to have a "preview" when you plug your nodes into a Cycles output.

Or also use the preview in Properties Panel > Materials > Preview

I use those, but they show only the final material as would be rendered.  I want to see the data at various points throughout the node network.

@DarenW Yes.. unfortunately, AFAIK that's as close as you can get currently. (you can use multiple outputs, but you have to disconnect the other ones to make sure it's actually using the right output..)
And you can't see different points at the same time :(


text:
Why do normal map ridges become grooves in mirrored object?
My model has a pair of objects, one a mirror image of the other, like bookends or a pair of wheels.  They use the same cycles nodes material involving a normal map.  Ridges on the one object appear as grooves in the other.  It looks as if the normal-x component and the mesh x coordinates aren't in sync.
Note that I prefer to use normals, rather than the Displacement input of the Material Output, due the nature of the work, fine details. I don't care about seeing bumps or groove profiles along the edges of the objects.  But I did try Displacement anyway, and got the same result.   The attached images might not be the perfect example, but shows the problem.
I thought maybe "Apply Transform" might fix it, so each object has points in the same world coordinates, but nope, this didn't fix it.
Added note: experimenting on a new scene, it seems that applying the transform causes the problem. For the example shown, I had already applied the transform a few weeks ago when starting the project.  So the question is: how to have ridges not grooves for an already-applied-transform mirrored object?

Related: http://blender.stackexchange.com/questions/1093/mirror-reflection-invertion

I think the negative scaling is getting applied, flipping the normals inside out. Try going into edit mode on the object where the normals are incorrect, selecting everything and doing CtrlF > Flip normals.


text:
Adding UV Mapping to Mesh
I am trying to apply an image to a wavy mesh I created in Blender. I am not sure how to do this. I don't think I have any seams because its one panel so I tried just unwrapping which didn't work. Then I tried marking the edges as seams but this also failed to work. Where are the seams if any and how do I apply an image?

I'm afraid your link doesn't work here, can you add a screenshot? stackexchange allows adding pictures inside the posts.

Do you want to unwrap this as one object?

Yes. I have an image to span the entire side of the container

Blender has a difficult texture mapping system.
To view an image on a 3D model, you need to do the following:

Select a mesh object and go to Edit Mode.
If the mesh has not been unwrapped, define your seams (Ctrl + E > Mark Seams) and unwrap it (U). Only the selected faces will be unwrapped, so make sure you have what you want unwrapped selected. Also, only the Unwrap choice guarantees that faces will have the same more or less spacial layout in UV space as they have in the 3D mesh surface, seams included.

Switch to a UV Image Editor while still in Edit Mode.
If your mesh has been unwrapped and there are some faces selected in the 3D Viewport, these faces' uvs should appear in the UV Image Editor. If this does not happen, make sure there is no render result displayed on the UV Image Editor.
Now you can assign an image to your mesh by either opening a new one from the menu Image > Open, selecting an already opened image from the drop down menu or generating a new image from the menu Image > New.
This image will be applied to the selected faces. However, it may not appear in the 3D Viewport yet. For that to happen you have to set your 3D Viewport to Textured View by hovering the mouse inside it and pressing Alt + Z. You can also change it the view manually in the footer.

If you try to render your mesh, there will be no image on it. The image has simply been attached to the mesh's UV layer. To make the mesh render with this image, you need to explicitly create a material, add a texture and change the texture's type to Image, set the image, change the Mapping to UV and assign the texture to color.

Yes, it is long winded and confusing. Sorry :)

I understand how to do everything except "If the mesh has not been unwrapped, define your seams and unwrap it (shortcut U)" Can u please look at the image and explain where the the seams are because I am confused as to where they are. Thanks.

@BDGapps you don't need seams, it is a flat object. And if you did have any, they would be around the edges.

Seams usually show up as red so you may not have defined them (It's not very clear from the image), to define them use Ctrl-E->Mark Seam when in edge select mode. But even selecting the faces you want to unwrap and unwrapping them is sufficient. However I don't think the issue is with that. For instance, you haven't applied an image in the UV editor in the right screenshot.

If u look at my image on the right side you will see what shows up when I don't mark the seams. It does not look like the same mesh that has been unwrapped.

As explained in 4, only selected faces show up in the image editor. So if you select all with A you should see everything. I worry though that the rest of the mesh may not have been unwrapped. Did you select all before unwrapping? (I suspect not, if you haven't defined any seams)

If u look at it when I put an image over it the mesh doesn't unwrap correctly.

@BDGapps try going into top view and choosing Project from view when unwrapping. I don't know why you are getting so many pieces. Additionally, make sure you have no stray seams about. Use Ctrl + E to clear them

To get continuous faces of the mesh stay continuous in UV space you need to use the first Unwrap option, not smart unwrap or lightmap packing.

@Psy-Fi I am just using the regular unwrap

@iKlsR can u please explain what you mean by this "choosing Project" from view when unwrapping

@BDGapps go into the view where the large side of the object is visible and press U to unwrap, but choose Project from view, this should make a flat uv map.

Then you must have defined seams everywhere. Delete them by selecting everything and using Ctrl-E->clear seams. Define them properly, only at the sides of the Container. Note after redefining seams, you have to reunwrap.

@Psy-Fi am i doing mark seam or mark seams

Oh, it's singular, sorry :)

@iKlsR I have no "Project" in view. Next to where I select that I want to view to be UVImageEditor the next button says view but when I click on it Project is not there.

@BDGapps Project is an option when you press U for unwrapping

@iKlsR that got it to work but the graphic is on both sides of the container and I only wanted it on the outside

@AntonyRiakiotakis by any chance can you please update python script for the same

You definitely don't need seams for this mesh. Seams are to unwrap something that is not flat like a ball or character.
I recommend the following:

In edit mode select all vertices A

Ctrl + E, choose Clear Seams

Deselect all with A, then select only one wall of your model. C is a good tool for this.

press the numpad 1 or 3 so that the viewport is looking directly at that wall. It's best not to be in perspective mode, change to Ortho by pressing 5.

Press U and choose Project from View

Because you only have one wall selected, in the Image Editor there will only be one wall . Use G to grab, R to rotate your unwrapped mesh in the Image Editor. Preview in the 3D Viewport to line up your texture as you like.

Repeat steps #3. through #6. for each wall. Note that its ok if your walls over lap in the Image Editor when all selected. Also, a good tip is, if  Numpad 1 gives you the view of the front wall Ctrl + Numpad 1 will give you the back.

If you haven't already, follow Psy-Fi's #7 step to add you texture to the mesh as a material texture. Now you can render.

A couple things you need to understand about this texturing process is:
Un-wrapping your object and opening an image in the Image Editor has not textured your object even if the texture shows up in the Viewport. Only when you actually assign a material with the desire texture is it textured. The reason is, Blender's Image Editor is a really powerful tool that allows you to paint a image texture by drawing directly onto your mesh object in Texture Paint Mode. So, it allows you to view images on a mesh even when they are not its assigned texture.

i updated your post with the kbd syntax, have a look at the source.

Project from view is indeed how an image would have been mapped onto this container in reality. Seams are used by the Unwrap tool which will flatten and stretch out the side as if it was e.g. a piece of cloth. If an image is mapped like that it will be distorted too much.

For macOS

Add a Workspace selecting General > UV Editing

Click the Edit Mode or press the Tab button on macOS

At the bottom menu, select UV > Lightmap Pack

Click OK


text:
How to draw a 2D bounding box of a 3D object
I'd like to visualize a bounding box of a 3D object in the 2D rendered image like in the example image below.

My idea is to use the line draw function presented here but I don't know how to transform the 3D bounding box coordinates in the object into 2D coordinates for the line drawing.

related: http://blender.stackexchange.com/questions/7198/save-the-2d-bounding-box-of-an-object-in-rendered-image-to-a-text-file


text:
How to find evenly spaced coordinates/point cloud of an object?
I'd like to convert a mesh object into a point cloud. I started using the vertices:
coordinates = []
for x in range(len(obj.data.vertices)):
    v = obj.matrix_world * obj.data.vertices[x].co
    coordinates.append(v)

Plotting the coordinates I get a point cloud as expected:

However, depending on the mesh, there are huge irregular gaps between the points. Is there a way to "interpolate" between the coordinates to get a regular pointcloud?
I found this proposal but couldn't make use of it.

Are you planning to use this data in Blender or another program?  Your answer may allow different answers to the original question.

Thanks for your hint, I am planning to export the coordinates.

Consider the Remesh Modifier. [Apply] the Remesh modifier with the button in the modifier to get a new mesh with vertices equally spaced as a simple description.
Remesh On Below.  View Eye Active.

Remesh Off Below.  View Eye Inactive.

You may also consider the Loop Cut Tool if you want some particular control of the division of loop cuts.

A Blender Particle System can emulate the point cloud.

Close up view of the particles emitted from vertices.

to have even space / grid like you may use emit: faces + particles/face = 1 (onli for jitter variant..) or so

Thank you, the remesh method works fine! However, I am still facing one problem: If the mesh is not "one piece" it gets deformed very badly (I hope that description is clear)

Ahh, stupid, I didn't see the "Remove disconnected pieces" option. So thanks again!

A solution is to set particles on the object and to use GRID instead of (default) random in the settings
(Note that also works on Volume, if the case, to fill with points)
Use No for physics to get fixed particles.

To further get the coordinates of those particles use:
gridVectors = [p.location for p in bpy.data.objects['Cube'].particle_systems[0].particles]

that if u need to further use coords in script

Also note that the grid acts a bit weird sometimes, more like the remesh tools, so the particles may or may not be on the faces, but rather at a distance, not quite controllable.
In the pic, I added particles to these meshes with settings as shown.

You wrote [a variant]. A variant of what?

A variant of getting even points. By saying "a variant" I assume there are other ways. Also I'm not very pleased by the level of control over grid particles, or how they work sometimes.    Should I say "a solution" ?

Thank you, but I can't find this option in Blender 2.74. What is the Python API method for this action?

Sorry, I updated now to show I use particles. And what you see is particles settings.


text:
Limited set of output codecs in Fedora Linux. How can I enable others?
I'm trying to render a video using blender, it have some images and sound, if I render it using just the default options I get no sound.
Searching on internet I found that I need to use other format than AVI JPEG to set some codecs options, I just have "AVI JPEG", "AVI RAW" and "FRAME SERVER". I'm keep looking but I can't found any information to solve my problem.
Im using fedora and actually I have
xvidcore-1.3.2-5.fc20.x86_64
ffmpeg-2.1.7-1.fc20.x86_64
packages installed.
EDIT:
When I had the problem I had the last version of blender installed from blender download site, I also tried installing blender from dnf, also tried with buildbot, so this answer didn't solved my problem.

Blender is shipped with fedora, but without ffmpeg. Try downloading an official blender version from blender.org.

@poor at least my fedora doesn't come with blender, I have blender installed from the website.

mmh, also using CentOs (rhel) here and I get this selection: https://i.sstatic.net/zqwE0.png - my os should be older than yours... weird.

Possible duplicate of How can I enable mp4/h264 as an output option?

@Samoth as I already pointed out in the comments: I downloaded blender from Blender.org and that didn't solved my problem.

@lcjury Yeah, Linux and Packages... it doesn't always work like one would want... So you need to ensure, Blender is using the correct ffmpeg libraries. And that these support the codecs you want to use. Have you tried the buildbot Version mentionend by insaner below? But the usage of ffmpeg is buggy on Windows as well, so don't be too sad about your system. But maybe another Linux might work better with Blender. Didn't try it out myself yet as I need AviSynth with Blender on Windows with Pismo File Mount...

@Samoth I'm going to start being Ultra Super specific with my question :/

Fedora ships blender with ffmpeg disabled for stupid legal reasons.
You can rebuild blender from the fedora source rpm with -DWITH_CODEC_FFMPEG:BOOL=ON as root as follows:
# cd /var/tmp
# dnf download blender --source
# rpmbuild --rebuild blender-*.src.rpm

The latter will most likely fail which is fine because that would be the one you already have. Install the BuildRequires:
# awk '/BuildRequires:/{print$2}' ~/rpmbuild/SPECS/blender.spec \
    | xargs -r dnf -y install

Enable ffmpeg, rebuild and install:
# perl -pi~ -e 's/WITH_CODEC_FFMPEG:BOOL=OFF/WITH_CODEC_FFMPEG:BOOL=ON/' \
    ~/rpmbuild/SPECS/blender.spec
# rpmbuild -bb ~/rpmbuild/SPECS/blender.spec
# dnf reinstall ~/rpmbuild/RPMS/x86_64/blender-[0-9]*.x86_64.rpm

Now you have blender with matroska, h264 etc :)
Optionally versionlock your version:
# dnf install python-dnf-plugins-extras-versionlock
# dnf versionlock blender

Pål

I just ran into this same problem, and didn't see this question, someone else linked to it from mine. I too use fedora (fc17 in my case) and using the buildbot self-contained build (which you don't need to install, just unzip and run the blender executable) I got all the expected codecs showing up as options. I'm currently working on making a spec file to easily turn it into an rpm so you can install it via yum, rpm or whatever. I will update this answer once I've done that.
Hope that helps.
EDIT:

For you fedora users out there, I included the promised RPM .spec file in my answer to:
How can I enable mp4/h264 as an output option? so you can package the standard binary builds from blender builder.
Please let me know if it helps any of you.

Blender from the fedora repository doesn't have that option.
In fedora 34 you can install Blender using flatpak. First you need to install the flathub remote
flatpak install flathub org.blender.Blender

There it does have the File format FFmpeg Video in the output properties.
Now we can continue with cretaing a text animation with transparency.
As metaphor_set say if you install from the official website you must have installed FFmpeg in your operating system.
To install ffmpeg install RPMFusion repositories(both free and non-free) then run.
sudo dnf install ffmpeg

First thing to check: Is ffmpeg installed in the system. "rpm -qa | grep ffmpeg" should list what exactly is installed. If Blender doesn't find the binary, it doesn't list the option.

With the pictures and sound in the VIDEO SEQUENCE EDITOR, In the Render Tab choose the following settings :
RENDER -> ANIMATION
OUTPUT -> H.264
PRESET -> H.264
FORMAT -> MATROSKA (MP4, AVI, XVID, etc..)
CODEC -> H.264
AUDIO CODEC -> AAC

Have you read my question or I explained it wrong?
"I just have "AVI JPEG", "AVI RAW" and "FRAME SERVER"". I don't have the output option "H.264" and I can't see the encoding menu.


text:
Blender 2.8: face on edges get inverted when doing the beveling operation
I am trying to bevel(Ctrl + B) an edge but it gets inverted

What have i done so far

Ive tried Ctrl+N to normalize object -> doesnt work
tried Merge vertices by distance -> doesnt work

please advise

to recalculate the normals select all and Shift N (not Ctrl N), maybe try that?

thanks it works :)


text:
Possible to keep materials after remesh?
I'd like to:
Join multiple meshes/objects with Ctrl+J, they all have different materials.
Is it possible to preserve material data where it's remeshed?

are we talking about materials with uv and image textures? Or simple colors?

Materials, not baked textures.

Join - keeps materials ... Remesh - generates completely new topology and materials are not preserved since they are originally assigned to a specific vertices.