text:
How to change the alpha blend amount with sideways transition?
I have this graphic in an answer in another SE site:

It has been produced in Inkscape, and I can easily make various parts into separate PNG files (by using layers).
My objective is to make an animated GIF (or movie) where the opacity of the blue line which goes from Tx to Rx moves sideways over a couple of seconds, to indicate the data movement.
Thus, holding the rest of the image unchanged, the blue line (the one with the arrows) might start at 50% opacity, and smoothly turn to 100% opacity, from left to right.
So far I have the blue line in a separate PNG file, and the rest of the image in another one.

Arrow:

The rest:

I made a mask, and keyframed its shape so that it gradually covers the area occupied by the area. But now I'm stuck.
I can't put it all together to get the effect I described.
So far I have this in the Video Editing layout:

But:

The mask affects both images
It just makes the image white rather than change its opacity, like this:

I've also tried various things in the Compositor without any real success.

Is there a simple and easy way of achieving this?

This is an extremely late partial answer but you may want to try this in the 3D view, create 2 planes for your two images, add another plane with a mask transparency, change the pivot point to the edge, keyframes the size and etc.

@Bradman175 That's helpful, thanks! I set up a plane with the first image, but am a bit unsure about making a mask transparency that moves sideways. Is there a link to a tutorial for doing that? Is it something you would do in the 3D view, or the Compositor?

When I have time, I will make a proper answer with some images.


text:
Weird faces blinking / overlapping problem
I stumbled upon a weird problem while modelling a wall of a building. I started with a plane, then added windows by subdividing faces (Ctrl+R) and using insets (I). Then I dissolved some edges that  didn't seemed important for my model. However after dissolving them, faces started to look weird/glitchy, like they were overlapping. Apart of that, I can't select separate faces, feels like something is covering them. That's a bit counter intuitive for me since i'm working with a 2d plane so it should be impossible for faces to overlap.
When I try to extrude, I get a sort of copy of plane, not the actual extrusion.
All this makes further work on this model impossible and forces me to rollback a few steps, which isn't a big deal, but I'd like to understand what causes this issue to avoid it in future.
I would be grateful if someone more knowledgeable could explain it to me. Please take a look at the video in the link to see what the problem looks like.
problem with 'overlapping' faces

Try Remove Doubles and search here for Z-fighting.

ye it seems as you have overlapping faces....Remove double might or might not work if it doesnt you should try and find yourselft what is happening

source: Stack Exchange

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

sort: votes


text:
Water simulation doesn't show shaded mesh in viewport
In Blender 3.1 I can't find the option to see my shaded liquid mesh in the viewport. All I see are coloured particles (left image), but as you can see on my right image it renders fine.

How can I see the render in the viewport and not the particle stream?

Could you upload your .blend file? It's rather hard to know what's causing the problem.

Done. Please note that theres no Bake included. Should be enough to quickly do a low res simulation at your end to be at the same point as me.

Select Domain and go to Object Properties > Viewport Display > Display as ... you have set Bounds ... set Textured. To hide "rainbow" particles go to Particle or Modifier properties and disable monitor icon.

@vklidu that's what I have technically mentioned in my answer... If the OP read it, that is.

Thanks for the answer. The problem was I was still showing the liquid particles. Turning them off was the solution. Thank you.

@NiclasW. Ah well... By the looks of your question it felt like you couldn't see your sim, so I never mentioned particles. Anyways, at least you got your answer :-)

@vklidu post it as an answer to get it accepted, would help others

@vklidu Edited, thanks for the suggestion :-)

Particles display
If you want to make the particles disappear, you have two options:

Or if you want to do this:
You probably have accidentally set the Visibility to bounds:

Thank you for your answer. It's not about baking. I already baked the simulation, and I also know how to change my particles. Also the mesh tab is activated. I want to shade my simulation, but can't get rid of the view I posted above.

@NiclasW. Check my edits.

Yes, I checked, but the problem weren't the bounds, but the particles from liquid occluding my mesh. Thank you.

@NiclasW. Well, I have mentioned hiding the particles. Though no problem, have fun

Blockquote
Select Domain and go to Object Properties > Viewport Display > Display as ... you have set Bounds ... set Textured. To hide "rainbow" particles go to Particle or Modifier properties and disable monitor icon.

Turning off particles was the solution. Thanks.

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


text:
Object disappearing in animation timeline
I’m extremely new to blender and following along a grease pen tutorial, it was going well but when I’m in the animation workspace my object disappears on the timeline after about 20 keyframes while in the tutorial he is able to move the timeline to 125 without the object disappearing.
The tutorial I’m following didn’t change or add anything to my knowledge to extend it, and I’m not sure if I’m getting terminology wrong as nothing comes up when googling it so I’m just stuck wondering what went wrong. I attached the tutorial (time stamp 5:39), I've also uploaded my file to blend exchange if anyone needs to look at the file.

The link to your Blend file doesn't do anything.

@JohnEason should be fixed now

Very strange! It disappears between frame 20 and 21 and there's no sign of any other keyframe or object that could be causing it as far as I can see.

@JohnEason well thank you for looking at it at least ahah!!

See my comment to @vklidu's answer which does indeed sort your problem.

Switch Timeline to Dope Sheet > Grease Pencil and delete keyframe on frame 21 ...

Ah. Yes. Not knowing much about grease pencil, I wondered what the 'Walls' entry was doing in the Outliner. You have to select that before those keyframes appear and you can then delete them.

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


text:
Segmentation fault if adding gabor.osl script node
In shading, after adding the script node, I select gabor_noise.osl ...
shader gabor_noise(
    point Point = P,
    vector Direction = vector(1, 0, 0),
    int Anisotropic = 0,
    float Bandwidth = 1.0,
    float Impulses = 16,
    output float Gabor = 0.8)
{
    Gabor = noise("gabor", Point,
                  "direction", Direction,
                  "anisotropic", Anisotropic,
                  "do_filter", 1, // Set to 0 to disable filtering/anti-aliasing
                  "bandwidth", Bandwidth,
                  "impulses", Impulses);
}

... which in turn crashes blender.
$ sudo prime-run blender
Read prefs: /root/.config/blender/2.92/config/userpref.blend
DEBUG:BlenderGIS-225.core.checkdeps:GDAL Python binding unavailable
DEBUG:BlenderGIS-225.core.checkdeps:PyProj unavailable
DEBUG:BlenderGIS-225.core.checkdeps:Pillow available
DEBUG:BlenderGIS-225.core.checkdeps:ImageIO Freeimage plugin available
Read blend: /home/me/src/blender/shark/shark.blend
ERROR (bke.fcurve): ../source/blender/blenkernel/intern/fcurve_driver.c:1035 dri
Writing: /home/me/src/blender/shark/tmp/shark.crash.txt
/usr/bin/prime-run: line 2:  1067 Segmentation fault      (core dumped) __NV_PRIME_RENDER_OFFLOAD=1 __VK_LAYER_NV_optimus=NVIDIA_only __GLX_VENDOR_LIBRARY_NAME=nvidia "$@"

$ cat shark.crash.txt
# Blender 2.92.0, Commit date: 2021-02-24 16:25, Hash 02948a2cab44
bpy.ops.node.select(wait_to_deselect_others=True, mouse_x=1163, mouse_y=815, extend=False, deselect_all=True)  # Operator
bpy.context.space_data.context = 'OUTPUT'  # Property
bpy.context.space_data.context = 'RENDER'  # Property
bpy.context.scene.cycles.device = 'CPU'  # Property
bpy.ops.node.add_node(type="ShaderNodeScript", use_transform=True)  # Operator
bpy.ops.node.translate_attach_remove_on_cancel(TRANSFORM_OT_translate={"value":(-409.649, 215.419, 0), "orient_type":'GLOBAL', "orient_matrix":((1, 0, 0), (0, 1, 0), (0, 0, 1)), "orient_matrix_type":'GLOBAL', "constraint_axis":(False, False, False), "mirror":True, "use_proportional_edit":False, "proportional_edit_falloff":'SMOOTH', "proportional_size":0.793446, "use_proportional_connected":False, "use_proportional_projected":False, "snap":False, "snap_target":'CLOSEST', "snap_point":(0, 0, 0), "snap_align":False, "snap_normal":(0, 0, 0), "gpencil_strokes":False, "cursor_transform":False, "texture_space":False, "remove_on_cancel":True, "release_confirm":False, "use_accurate":False, "use_automerge_and_split":False}, NODE_OT_attach={}, NODE_OT_insert_offset={})  # Operator
bpy.data.materials["gabor"].node_tree.nodes["Script"].mode = 'INTERNAL'  # Property
bpy.data.materials["gabor"].node_tree.nodes["Script"].script = bpy.data.texts["gabor_noise.osl"]  # Property

# backtrace
blender(BLI_system_backtrace+0x34) [0x558e3aab67e4]
blender(+0xe14cfd) [0x558e3858dcfd]
/usr/lib/libc.so.6(+0x3cf80) [0x7f5a2c3e6f80]
/usr/lib/libjemalloc.so.2(+0x4c9d4) [0x7f5a35b079d4]
/usr/lib/libjemalloc.so.2(+0x14ec7) [0x7f5a35acfec7]
/usr/lib/libjemalloc.so.2(+0x16c3b) [0x7f5a35ad1c3b]
/usr/lib/libjemalloc.so.2(+0x74e29) [0x7f5a35b2fe29]
/usr/lib/libjemalloc.so.2(+0x114b6) [0x7f5a35acc4b6]
/usr/lib/libjemalloc.so.2(_ZdlPvm+0xf) [0x7f5a35b343df]
/usr/lib/liboslcomp.so.1.11(_ZN9OSL_v1_113pvt11SymbolTable11delete_symsEv+0x4b) [0x7f5a32eb734b]
/usr/lib/liboslcomp.so.1.11(_ZN9OSL_v1_113pvt15OSLCompilerImplD1Ev+0x273) [0x7f5a32ea6543]
/usr/lib/liboslcomp.so.1.11(_ZN9OSL_v1_1111OSLCompilerD1Ev+0x12) [0x7f5a32ea67a2]
blender(+0x2b42335) [0x558e3a2bb335]
blender(+0x217f7a4) [0x558e398f87a4]
/usr/lib/libpython3.9.so.1.0(+0x14cab2) [0x7f5a2e914ab2]
/usr/lib/libpython3.9.so.1.0(_PyObject_MakeTpCall+0x30d) [0x7f5a2e8fae9d]
/usr/lib/libpython3.9.so.1.0(_PyEval_EvalFrameDefault+0x5023) [0x7f5a2e8f6b73]
/usr/lib/libpython3.9.so.1.0(_PyFunction_Vectorcall+0x1aa) [0x7f5a2e9029ea]
/usr/lib/libpython3.9.so.1.0(_PyEval_EvalFrameDefault+0x3c5) [0x7f5a2e8f1f15]
/usr/lib/libpython3.9.so.1.0(_PyFunction_Vectorcall+0x1aa) [0x7f5a2e9029ea]
/usr/lib/libpython3.9.so.1.0(_PyEval_EvalFrameDefault+0x498f) [0x7f5a2e8f64df]
/usr/lib/libpython3.9.so.1.0(_PyFunction_Vectorcall+0x1aa) [0x7f5a2e9029ea]
blender(+0x16f84ce) [0x558e38e714ce]
blender(+0x165905d) [0x558e38dd205d]
blender(+0x16138fc) [0x558e38d8c8fc]
blender(+0x1563cab) [0x558e38cdccab]
blender(+0x1a7ee30) [0x558e391f7e30]
blender(+0x1a90b59) [0x558e39209b59]
blender(+0x119ee90) [0x558e38917e90]
blender(+0x119f51c) [0x558e3891851c]
blender(wm_event_do_handlers+0x298) [0x558e38918b88]
blender(WM_main+0x22) [0x558e3890ee52]
blender(main+0x367) [0x558e385575a7]
/usr/lib/libc.so.6(__libc_start_main+0xd5) [0x7f5a2c3d1b25]
blender(_start+0x2e) [0x558e3858a0ae]

# Python backtrace
  File "/usr/share/blender/2.92/scripts/addons/cycles/osl.py", line 30 in osl_compile
  File "/usr/share/blender/2.92/scripts/addons/cycles/osl.py", line 91 in update_script_node
  File "/usr/share/blender/2.92/scripts/addons/cycles/__init__.py", line 103 in update_script_node

$ sudo prime-run blender --version
Blender 2.92.0
        build date: 2021-04-25
        build time: 11:39:34
        build commit date: 2021-02-24
        build commit time: 16:25
        build hash: 02948a2cab44
        build platform: Linux
        build type: Release
        build c flags:  -Wall -Wcast-align -Werror=implicit-function-declaration -Werror=return-type -Werror=vla -Wstrict-prototypes -Wmissing-prototypes -Wno-char-subscripts -Wno-unknown-pragmas -Wpointer-arith -Wunused-parameter -Wwrite-strings -Wlogical-op -Wundef -Winit-self -Wmissing-include-dirs -Wno-div-by-zero -Wtype-limits -Wformat-signedness -Wrestrict -Wnonnull -Wabsolute-value -Wuninitialized -Wredundant-decls -Wshadow -Wno-error=unused-but-set-variable -Wimplicit-fallthrough=5 -D_FORTIFY_SOURCE=2 -march=x86-64 -mtune=generic -O2 -pipe -fno-plt -fuse-ld=gold -fopenmp -std=gnu11 -msse -pipe -fPIC -funsigned-char -fno-strict-aliasing -ffp-contract=off -msse2
        build c++ flags:  -Wredundant-decls -Wall -Wno-invalid-offsetof -Wno-sign-compare -Wlogical-op -Winit-self -Wmissing-include-dirs -Wno-div-by-zero -Wtype-limits -Werror=return-type -Wno-char-subscripts -Wno-unknown-pragmas -Wpointer-arith -Wunused-parameter -Wwrite-strings -Wundef -Wformat-signedness -Wrestrict -Wuninitialized -Wundef -Wmissing-declarations -Wimplicit-fallthrough=5 -I /usr/include/python3.9 -fuse-ld=gold -fopenmp -std=c++17 -msse -pipe -fPIC -funsigned-char -fno-strict-aliasing -ffp-contract=off -msse2
        build link flags:  -Wl,--version-script='/build/blender/src/blender/source/creator/blender.map'
        build system: CMake

Does it relate to building blender for scripting by myself?
Similar problem.

The easiest way is to download official build to test if crash's too as your build. Or try to Load factory settings under File menu > Defaults. Sorry I can't help with reading crash log.


text:
How to set background material as an object material in cycles?
How do I set an object to render as the background material? As shown in the below images the Sphere and background would render out as transparent in a PNG sequence.
Images are just sample. For my use, boolean or similar doesn't work, so some magic material would be best :)
In old Blender it was known as something like "set background as a material".
Any help greatly appreciated!

What you show looks like the Shader > Holdout node:

You can also enable the Holdout option in the Object panel > Visibility > Mask:

Also as Vklidu suggests, you can enable the Holdout option for a collection in the Outliner, remember to activate in the Outliner's filter:

To make your background transparent, go into the Render panel > Film, and enable Transparent.

@vklidu oh yes thanks I forgot this one

... too many options :) You can delete me from description to clean it up :)

Yes!! I completely forgot about holdout!! Huge thanks!!


text:
My imported Character from Daz 3d appears black when rendered in cycles, but the materials are normal in look-dev mode
I imported a character I designed in Daz 3d and when It came already Uv unwrapped, but when I add image textures from polygon onto the character it appears in look dev mode perfectly fine.

However when in render mode it appears completely black even with the light intensity maxxed out. Help please I'm very new to blender and have been trying to figure this out for days

Are there lights in the scene? and are they string enough?

yes  I put the light directly in front of the characters face with the size to .5 to accurately test it, but at most there are little shiny spots but its almost completely black

Increase the power to some large number and try

unfortunately that also doesn't seem to work, even with the wattage at 5000 for the light, could it be an issue with the nodes?

Is there any duplicate mesh that is fighting the one you are looking at, and do your mesh normals point outward?

Please attach simplified blend file via https://blend-exchange.giantcowfilms.com to let us check your setup. Thank you

Go into Blender Modifier and select Subdivision surface and it will work. Thanks


text:
How to unlock the subdivision settings
I can't figure out how to get it back to being normal, with it set like this, I'm unable to change any of the green-highlighted settings.
How do I fix this?

The green color (and the yellow on Optimal Display) indicates you've set keyframes for those values. Right-click on them and choose "Clear Keyframes".
Green color means, there are keyframes for this value but not on the frame you're currently on. The yellow color means, there is a keyframe right on this frame.
When you are on a yellow-colored value, right-clicking also gives the option to "Delete Keyframes". If you do this, only the keyframe on this frame will be deleted and others (if there are any) will stay, so the color will switch to green.
If you want to completely get rid of them (because it seems you've set them accidentally), then "Clear Keyframes" is what you want to  do.


text:
Import a path from a csv file and display it on a mesh?
I have created a mesh (.obj) and run several A* searches on it which yields to me a .txt file where each line is:

x,y,z
x1,y1,z1
...

I would like to find a way to ideally import these as a single object, showcasing the route my A* search took along the mesh, but haven't found anything that seems to support that such a request is even possible. Am I missing something here?
EDIT: Here are some screenshots to highlight the data I am working with to hopefully make the question clearer.

Image1: This is the mesh my process makes (the holes are expected), where the obj consists of the vertices and faces which
compose it.

Image2: After running A*search, this is the type of output I have, where the path is just a list of vertices visited. I am able to index them to the structure that holds their coordinates for the proposed line I want.

Shortest path between start and end nodes on mesh found. ['start', 50502, 50504, 49191, 49193, 47885, 46610, 46612, 45361, 44131, 42932, 41745, 41747, 49583, 39442, 38322, 37213, 36176, 35120, 34086, 33055, 32041, 31045, 30068, 29098, 28140, 27195, 26270, 25351, 24602, 23779, 22490, 21352, 20240, 19154, 18098, 17064, 16059, 15082, 14134, 13214, 12536, 12576, 13495, 14441, 15417, 16421, 17454, 18511, 19592, 20704, 21844, 23009, 24176, 24923, 25846, 26775, 27711, 28688, 29658, 30638, 31625, 32633, 33659, 34694, 35744, 36810, 37900, 39020, 40152, 41305, 'end']

Image3: This is what I am hoping to accomplish. A line drawn on the mesh from each point to point.

object as in mesh, or curve, or edge curve or...?

Would a better title be: 'How do I import a path from a csv file?' ... Also, FYI,  the GN  Shortest Path node, (which is a Dijkstra search) will let you trace your paths directly, inside Blender.

I’d like it to be imported and displayed as line segments that I can change the color of for visualization purposes. Since the requirements of my project are that all computation regarding the build and search of the mesh needs to be self contained, I am only using blender/mesh lab for visualization and mesh design measurements.

What's a line segment? Curve, edges, polygons? I would recommend a curve, bc. you can easily change thickness and shape. But coloring different segments depending on the csv. might be tricky. But please provide more details and perhaps screenshots.

Added additional detail to make clearer my problem

Are the output numbers the indices of vertices or the coordinates (x,y,z)? Anyway, you can write a Python script to import the values and mark the corresponding vertices of the mesh. Or you can create a mesh line from them. Then convert it to a curve as you wish.

@Thomas ??? https://www.youtube.com/watch?v=-NOqNMWukl0 https://blender.stackexchange.com/questions/273207

version 01 - Shortest Path node
Robin Betts's comment is right - most direct solution could be use Shortest Path node under Geometry Nodes system ... you can get idea here or here. Since your Q is aiming to a different approach I'm not going to go further here.

version 02 - Text file (CSV) - Index of Vertices
You can copy values from your Image2 (I suppose values represents vertex numbers - indices) and place them into text editor. At row 1 type some name (like "short-path" or what ever) and run find/replace operator to change comma with space to enter character, so your text file end up with single value per row.  Save as .csv format.

This file you can import into a Blender with Blender Spreadsheet Importer mentioned in version 03.
Now when values are imported as vertex attributes, select your terrain object and use this geometry node tree to distribute vertices at their locations ... (big thanks to @RobinBetts answer again)

At last, to connect vertices into a path ad Realise Instances node and node group seen in last image of version 03. Note: the "B" value is just a limit of vertices to be connected.

version 03 - Text file (CSV) - XYZ
Import CSV data of XYZ as Attribute for Geometry nodes. Each row contains three columns of X Y Z values. For simplicity I used just three vertices. -the first at loc 0, 0, 0, second at 1, 1, 1 etc.

To import CSV data for Geometry Nodes use this great addon Blender Spreadsheet Importer by simonbroggi.

Data are brought into blender as object attributes ...

And set this node tree ...

... to generate line add this node group ...

Node group seen in image above ...


text:
I'm trying to make my model have a texture that flashes different colors at once
I need to know how to make the yellow fur texture become as a flashing color texture.
The colors for the flashing texture are in this order:
red - blue - green - yellow - white - purple
They have to be pastel variants of these colors in order to make this Super Sonic model become Hyper Sonic.
The particles should be sparkles.

This is just one of many methods. My example features 3 colors, but you can add as many as you need.
Here's the node setup (it is recommended you put everything in a node group, like I did. If you don't make sure there's a value input node in the place of the group input):First, it takes the value and compares it to a set number. Then, it changes the color depending on which value is true (You don't need one for the first color, since that's the color that will be displayed when all other values return false)I've animated the value with a simple linear function generator, and below is the resulting animation:


text:
Sticker not match the model after rendering

Sticker not match the model after rendering. How can I fix this.

Apart from the visual problem: Is it really a good idea to (graphically) suggest pouring hot coffee into a thin-walled glass without handle? Just a thought. ;-)

If you are saying the right screen is correct ... So that is just because of viewport limitation.
The left image (render) is actually a result of your shader setup ... Sticker appears on outter side and is doubled by appearing also on inner side of glass wall.
We don't know nothing about your material setup or model, but if you are using solidify modifier you should apply it and use UV texture coordinates to specify where sticker should appear.
Or more flexible way ... use a sticker as separate plane object Shrinkwrapped onto glass model (or deformed by another way around glass surface).


text:
Rigging is moving part of mesh in unwanted way
The spine is moving odly at the higher part - the mesh is stretching and I don't want it. How to change it?

Hello, hard to know, maybe share your file (the armature only if it has to do with the armature)

@moonboots how do I share the file here?

in weight paint mode hold shift and click in an area that is doing weird stuff. It should show you all groups the vertex belongs to. Odds are that some vertices are in groups they are not supposed to be in.

try https://blend-exchange.com/ if it's too heavy use another platform like workupload.com

@moonboots I edited the post with the link

Your goal is a rig or straightening spine? To make model straight you can create a curve along spine, add a strip deformed by Curve modifier, select model and assign Surface Deform modifier with Target to Strip, Bind it and disable Curve modifier for strip ... so your model becomes straight.

So it doesn't look like the bones are stretching, it's rather the mesh that is stretched, because these vertices are part of vertex groups that they should not be part of. When you parented you should have kept a straight mesh, not spiraled, so that they were no risk of bad vertex group assignment, so either straighten your mesh and armature and parent again, or here is a quick (but not ideal) fix:
Remove these vertices from the groups they should not be part of:

Then select the armature in Object mode, shift select the mesh, switch to Weight Paint mode, select the front bones, then Weights > Assign Automatic from Bones:


text:
Making a circular fade to transparent with nodes
So I have made my y axis of this plane 'fade' to transparent ...

any idea how I can set up some nodes to make it start fading from the blue circle and then be fully transparent by the time it reaches the red circle?

I have been trying a lot of different setups but can't seem to make a circular fade work
Any help is appreciated!

I think you need a simple circle (spherical)gradient, to control the transparency. Here a simple basic set up.You could add a math node before the ramp to control it, if the texture coordinate node is not enough.The texture could be, also,connected in the object space of the sphere,to let the transparency follow the object around

I guess you might also add that the texture can be put in the object space of the sphere, if @Cameron wants the transparency to follow the sphere around...

@Robin Betts .Yes, edited and added your suggestion, thanks.

Genius .... really great answer and exactly what I was looking for!!!

Deep appreciation from Deutschland!


text:
Saved image is darker than the render
After toggling every switch I can't seem to figure it out. Basically I have a test render (on the right), I saved it, and then I open it (on the left) and it is several shades darker
I have no idea why.

Read this thread: Blender image output gets greyish touch. As a follow up, learn about view transforms.

I'm sorry, but the image was not attached to the topic. Can you post them again, please?


text:
Bic Lighter - Solving subdivision warping issues while cutting holes
I have been a little stuck with this model and I can't seem to figure out how to ground these cuts in the proper way so that my mesh does not warp. In my mind the way it is modelled now should be very smooth, but it has lots of warping around the cuts.
Anyone know of a decent solution? Any on hand example someone could share?

THANK YOU!

UPDATE:
So I think one issue I am having are these loops cuts that are stemming from this cut out on the flame shield. I feel like I should probably be terminating these red lines elsewhere or ground that cut out differently but I have not found a great solution yet, however when I space out those red lines the issue does subside.

Also here is the incomplete .blend.
This is a WIP model and I had not yet figured out how to cut in the tab on the side in combination with the holes on the front. My subd modelling is a bit rusty.

hello do you have a reference image of the real object?

Hello and welcome. Please use a title that matches the content of the post. It should read like a question, be descriptive but succinct, unique and identifying, summarizing the problem so that anyone searching for similar issues is likely to find this. Remove anything superfluous, avoid using words like "this", "help with", "issue" or "question about", instead describe what "it" is. Remember, your title is the first thing visitors see, answers you get depend heavily on it. See What is the problem of asking “How do I do this?"

Your problem is that your getting into too much detail with too little topology. You have to think iteratively. Like start with the low-res cylinder shape, get the overall form figured out. Then add one subsurf to get the overall rounded shape. Then once you're happy there apply that and then model with that geo.

You can't expect to go from 8-16 sided cylinder to full model without some compromise. The messed up shading you see is that comporomise.
Your end goal is to have as close to even topology as possible, especially on curved surfaces.
Right here you have huge disparities in the spacing of your geo.

The one on the left has only 2x the cylinder sides and it looks alot better already.

Without modifiers.

Well I have certainly considered when and where to apply modifiers, but I was trying to keep this as simple as possible and often applying subd can lead to a lot of geo on places I don't want it.  I did update the post and include the asset I was working with if you are interested.

This is the nature of 3D modeling. You have to keep it as simple as possible while also adding detail where required to meet the needs of your project. That's just art, in general, really.

I think there are moments where you can't get around a mod commit, but you can absolutely step down the spacing of your geometry in different areas and still have a subd mod work fine. I posted an answer below, essentially giving those ends someplace to go.

It seems to work fine with this topology:

File:

Hey thanks! So I did try that ( I also uploaded the model to the post if you want to check it out ) and it seems like it still had warping to some affect ...

See my edit, I've linked my file

I got an answer up

Alright, so I finally solved this one.
What ultimately fixed the issue was basically extruding that inner edge, now I planned to do this with the solidify mod, and probably still will knowing that it will fix this issue, though I still would be interested if this shape could be cut out cleanly out of a mesh with no depth
However most things are 3D and this has 100% cleared up the issue I was having.


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Measure Tool - How to Copy Measurement Value to my Clipboard (Blender 2.80)?
How do I copy the active ruler/protractor's measurements to my clipboard in Blender 2.80?
In Blender 2.79, pressing ⎈ CtrlC could copy the value to the clipboard, but it doesn't work this way in Blender 2.80.
Always manually writing down or memorizing 5-digit measurements and calculating angles to decimal places is very time-consuming.


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Snapping to vertex while scaling
I want to snap the outer circle to the inner.

For that i turned on snapping to vertex, selected the scale affect, selected the outer circle and try to scale it down until dimensions of inner circle. But when cursor snaps to one of inner circle's vertices, the outer circles's dimensions jump to infinity, i guess. Like on the image:

Why is this happening?

In the snapping menu, under "Affect" section there is "Scale" button.

ok, I didn't know this option, it works fine for me, maybe show your snapping setup or share your file: https://blend-exchange.giantcowfilms.com/

Switch Pivot Point from Individual Origins to Median Point, don't ask me why in that case it made the scale and snap bug though.


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Blender 2.78c on CentOS python environment
What I am trying to do
Trying to run python modules such as osgeo(GDAL), and others in blender.
  These modules have been installed on the system python environment using pip.
Things i have tried
Deleting blender python environment
Fatal Python error: Py_Initialize: Unable to get the locale encoding
ImportError: No module named 'encoding'

Tried symlinking system python to replace blender python
Tried copying python libraries into blender libraries
Tried both python3.5 and python3.6 - i believe blender uses 3.6
What happens
Regardless of my attempts i get either the module cannot be found or python locale error
Other Information
I am running CentOS 7.  Blender 2.78c from binaries x64(blender.org).
What doesn't makes sense to me is when I install on ubuntu using ppa I don't have this issue.  I am trying to avoid compiling from source if possible for reason i am not going to get into here.
Any help is appreciated.
**Updates**
Installing Pip into blender environment
Pip now working in blenders python environment.  gdal fails to compile with gcc error importing Python.h
Successfully symlinked system python to blender python:
/usr/lib/blender/2.78/python/bin/python3.5m  --> /usr/bin/python3.5m

Blender now runs off system python environment but still does not see gdal
If i run /usr/bin/python3.5m  --> import osgeo : it works
If i run /usr/lib/blender/2.78/python/bin/python3.5m --> import osgeo : fails to import

If you can, install from system repositories. I've heard that CentOS's isn't very good at this, and on Windows you can't, so here are some other solutions.
The first thing to try is deleting the python folder from the blender install. (you don't need to symlink it, remove it entirely) This should make it use the system python.
The next thing to try is to install pip inside blender. This isn't too hard to do, and is useful in many other cases (eg want a portable version of blender with a specific module)

Download get-pip.py and rename it to get_pip.py
Start blender's python runtime (inside blender/2.78/python/bin/) and run the executable (python3.5m on linux 2.78c) from a terminal.
Add your download folder to the path so python can find get_pip. Do this with:

import sys
sys.path.append('~/Downloads')  # Change path as required

Now you should be able to import get_pip, and run get_pip.main().
Then, to install things, you can use:

import pip
pip.main(['install', 'osgeo'])

You could try it from blender's built in console, but on the windows version this does funny things (like opening lots of instances of blender!),  so I haven't gone into detail.

CentOS repos are terrible.  The newest version in repos is 2.68 that I can find.  I have already tried deleting blenders python environment and get a python error.  I will update question when I get home with specific error message.  I will try the pip suggestion also.  Thank you for your suggestions.

So I tried your suggestion.  I got pip working in the blender python environment.  However gdal fails to install referencing various libraries missing from python-devel.  I have this installed for all the versions of python installed on the system but since this is not part of those environments i cannot install it for this.  Not sure where to go from here.  Any other suggestions would be appreciated

I'm afraid I haven't come across this issue. You could try copying the necessary libraries from /lib64/python3.6 into blender/2.78/python/lib/python3.6 Also check inside the site-packages subdirectory - this is where pip puts things.

Thanks for your suggestions.  I'll keep playing around until I figure it out.

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


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Is it possible to completely go into fullscreen?
I have hidden everything except the top header with the menus. Is there a way to hide that? Would scripting this require a lot of work ?
Edit:
 thanks for the reply. It still leaves the top header with the menus.alt + f9 hides the bottom '''footer'''. Isn't there a button for hiding the top one? Would scripting of that be complicated ?
Edit2: here's what i would like to hide in the 3d view

...think you misread = F10 is what you should be trying not F9

ALT F10 = something somebody already thought of. Repeat ALT F10 to exit fullscreen mode.
This is what I get with mouse over default 3D layout ...

...and as Sambler says once more with F11 and even the Blender bar is hidden.

Alt-F11 also makes the window fullscreen - removing the window titlebar.

Oh I understand now. You must be in the 3d View Full (I was in the customized view) to use the alt + f11 and alt + f10. The shortcuts do not work in other views. However shift + space does not bring up the properties menu.


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Blender render transparency in 3d view. Normals/faces shading issues
what is causing that shading effect ? I need the bottle to be a little transparent and some faces  inside are not recieving any transparency. The effect dissappears when I set alpha to less than 0.3
I have tried recalculating and fliping normals, also checked the box  for double sided in ''type of data to display and edit'' shelf. I am out of ideas.

It looks like the effect is happening where the mesh has edges. Also mesh is subd'ed.

Not sure which effect you're trying to get, but try changing transparency method to Z-Transparency. This will create not masking but alpha transparency.

i basicaly need a transparent material to display in  the 3d view

backface culling helped a little bit but not entirely.


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Extruding outwards evenly
I would like to know how to extrude with even length in all directions. When I extrude with selected faces I get some lengths higher than the others.

This is especially seen when you subdivide:

Did you 'extrude and move on individual faces'? or did you 'extrude' on 2 axis? Also when you 'extrude and move on individual faces' you should first apply the scale and/or rotation (menu shortcut: CTRL + A).

Extruded with Alt + E -> region(vertex normals). Applying scale and rotation did not help either.

After the extrusion you can trim the 3 axis in the toolshelf (T).

does not work when extruding along vertex normals


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Randomly tint generated instances
I'm a relative Blender novice, but I've started using Geometry Nodes to generate a roof from a single roof tile mesh, adding randomisation to the position and rotation of each instance to create a somewhat jumbled, hand-made appearance:

This is done using what I imagine is a pretty clunky set of geometry nodes that I've made through trial and error:

What I want to do, but have so far failed to achieve by trial and error and internet searching, is to randomly tint the colour of each tile instance by varying the value of the material colour ramp factor for each instance, but I can't work what node to use, nor how or where to insert it into the node tree to affect individual instances:

Any help would be gratefully received. I've uploaded a copy of my Blender file here.

Simple instancing ...

... works with just Random.

Note:
If your node-tree contains Realize Instances node, use Input > Geometry node > Random per Island socket in material node-tree (works only in Cycles).

I can't believe it was that easy. That worked a treat. Thank you!


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While trying to make a walk/run animation CTRL+SHIFT+V doesn't work correctly
So, I'm following a tutorial to create a character + his walk and run animations.
The tutorial says to create half an animation and then we copy and mirror the 2nd half.
In the video - everything mirrors correctly for the guy, but for me mirrors the upper half of the body correctly (same position, angles etc. of the arms), but legs get deformed a bit.
As seen in these pictures (frame 1 and frame 9 which needs to be opposite to frame 1)

hello, please share your file: https://blend-exchange.giantcowfilms.com/

Are the bones perfectly mirrored? Try to see if the roll is the same on both the right and left leg in edit mode. Otherwise it could be an inverse kinematic issue.

Meant to say the legs should have OPPOSITE rolls (one positive one negative, same number).

@moonboots  here you go, didn't know how to do it when I created the problem. Thank you

@MrWaffleman I've done my model using the mirror modifier and after adding the core bones (middle) and the left side - I've used the 'Symetrize' option and when I reset the mesh with ALT+R & ALT+G to remove all rotations and such, it's symetrical! The left lower leg is at -177° and the right one has 177° roll.

The symmetry of the IK controllers is bad, here is what we have currently:

If I delete the right leg and symmetrize the left leg, here is what I have:

Now it works correctly, except I'm not sure about your feet Copy Rotation constraint but it's another problem... (I would rather parent the feet to the controllers and give them a Copy Location with the lower legs as targets and the Head/Tail value at 1).

SOLVED! Firstly, I wanna thank you. Really don't know how the symmetry got messed up since I selected everything and did the symmetrize, but does not matter now. I'm quite new to blender and for now I'm just following some basic tutorials and that's what the guy did in the video. After I get everything up and running, I'll re-do it and try your solution for the feet. Once again, thank you very much!


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Can you bake multiple rigid body simulations in a single file?
I've looked at various similar questions but ...
a) don't quite understand and
b) they were for older versions of blender.
I'm now on Blender 3.5
I am doing a Rube Golberg machine. First part is a ball rolling down shelves and into a basketball hoop which i've done wiht rigid body. Because it's finally worked i've baked it for frames 1-300 so it doesn't magically stop working.
I now want the ball to carry on it's journey and it's going to knock some other things down etc. Can i bake a 2nd sequence of events in the same blender file?
I think i've read somethings about different domains and compositing but if someone could explain in a simpler way that would be brilliant.
Thanks
Richard

If you want the same object to continue its course you'll need to enable its Animated option, then bake again

but that would be "hand animated" as opposed to adding rigid body to any other objects after that?
I've found that if i now add other objects to the scene, they interfere with the physics of the original objects (even though they're nowhere near eachother in the scene!!)

Could you please show an example of what you want, as simple as possible, it would make things clearer?

If you think about it, what baking rigid bodies mean and what the animated checkbox does, you should be able to answer your question yourself.
Baking a rigid body means:

Blender creates keyframes
Blender removes the rigid body

The animated (in rigid body settings of the object) checkbox (checked) means:

The object is still part of the rigid body simulation
The object won't move at all if you don't keyframe it

The animated checkbox (unchecked) means:

Blender "takes" the "velocity" (animated keyframes for location before) of the object and animates the object in its simulation

So if you want an object to be a rigid body after you baked it so that other objects react to it, you have to add the rigid body again and check animated. But be aware that even if it now e.g. crashes against another ball and this ball will move (if it has rigid body) your animated ball will just continue its speed without any effect to the collision because now it only has keyframes.
Note: There is never a "in-between" state for Blender. Either it is animated (it moves via keyframes) or Blender calculates rigid body simulation. But yes, you can change that every frame if you like.
For longer rigid body simulations you would "normally" make copies of all rigid bodies e.g. after 300 frames because you don't wanna start the simulation always from frame 0. So you "bake" all rigid bodies, then copy them, give them all rigid bodies again and check animated on frame 300 and uncheck animated on frame 301.
If you mean the baking of the rigid body world under "cache": AFAIK you can only bake it once.

I think this is the clearest explanation! thank you so much. Can i just check that i've got it right in my head.
I was at frame 1: Added ball and floor etc with rigid body and collisions etc, animated tick box was unchecked. Pressed Play and it simulated the movement etc BUT each stage of the movement is not assigned to a specific keyframe at this stage.
At frame 300. i stopped the simulation and baked it. This then stopped the stimulation and essentially locked in each location/rotation etc to a specific keyframe. [like it was almost hand animated]

So now, at frame 301 i check the "animated" box and it restores the rigid body world settings to the ball at surfaces but the ball will only move to where i have animated it to move?

@Chris ... Oh +1 ... now I see I wasted my few hours ... previously your answer confused me, especially first two points, I thought you mixed bake types ... now I realised I was working on version 3.4 ... but 3.6.5 LTS has the operator you mentioned Bake to Keyframes  (I'm not sure about OP's 3.5) .... Grrr

@BuddingBlenderer: yes, so if you wanna have a start velocity you have to keyframe location 2 times so that Blender takes it into account. And of course you have to keyframe checked animated and later unchecked animated.

you wasted a few hours....!? for that answer...really? cannot believe that.

@Chris ... old, slow ... ? :) WIth all the gifs, screens, optimisations, structured text, plus other approaches I wanted to try ... yes a few hours :) My bad. Time to upgrade my home machine :)

In this example I split sim into two parts ...
Frames 001-050

Scene Properties > Rigid Body World > Cache set Simulation Start 1 / End 50 and Bake cache

Select object you want to keep baked as it is and go to 3DView > Object > Animation (or search for) Bake Action operator and enable Visual Keying at frame range 1-50 (it will generate keyframes per each frame).

Frames 051-100

Scene Properties > Rigid Body World > Cache set Simulation Start 51 / End 100 and press Delete All Bake
for object with keyframed simulation go to Physics Properties > Rigig Body > Settings, check Animated and press "I" to create a keyframe for this checkbox at frame 50 ... go to frame 51 uncheck Animated and create another keyframe for this checkbox

now just repeat Bake Cache and Bake Action for these frames as described for first frame sequence

Notes:

You can simplify the process bellow by baking entire sim cache and use Bake Action operator for a frame range you set in popup window.
Your last paragraph "I think i've read somethings about different domains and compositing ... " Domains are related to fluid physics (volume, liquid) there is cache stored into individual files per frame (can be also saved externaly) and can be combined in various ways since only naming convention matters. Compositing is also possible, but it is based od rendered images.*


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How do you create interactions with other objects?
I have this little Ball i made up, however i have a problem, I can get the ball to interact with other object, however i cannot get the test objects to move from the impact, what am i doing wrong?
Edit:
I placed a cylinder in the scene however the ball when making the impact with the cylinder wraps itself around the cylinder, i do not want that, i need for the cylinder to knock over or have other objects in the path to interact with the ball

Can you give a little bit more detail on what the end result that you are trying to achieve is? From the sounds of things though, you may want to consider looking into rigid body physics.

Please add screenshots of your problem and provide a .blend file to be able to help you

@Tak sorry for being late on this but I cannot find a way to post the blend file i am sorry i cannot for the life how to attach the file.

@BenMadison http://blend-exchange.giantcowfilms.com

@Tak thanks and their you go i got a old version of blender but it is safe i added so stuff to the ball to make it pretty.

@BenMadison answer provided with screenshots and an updated .blend file. You can accept the answer if it solved your problem :)

You need to use rigid body physics to do what you want.

Select your sphere, then add Dynamic Rigid Body to it as shown below:

Then select your ground plane and add Passive Rigid body to it as shown below:

This is the result, the sphere will fall and when it hits the plane it will land and stop as shown below:

Updated .blend file can be found here:


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Wrong textures appear in rendered view
So, I have tried a tutorial about building a medieval house and everything worked quite okay for me until I came to the point of applying textures. I didn't follow the tutorial there because i remembered doing it differently a few years ago. I got into it again quite well and applied almost all the textures to the faces BUT... in my 3D view it looks like this, well, like it is supposed to look. Somehow.
And then when I look at it in rendered view, it shows that somehow only the stonewall texture got applied to some of the faces.

I tried activating the wooden frame around the house and apply the texture again but the suddenly all the textured faces from the second image were covered with the wooden texture.
I put a new material, put a new texture, clicked on assign in the material window and everything, I just can't get it. Also, what is bothering me is that i can't seem to apply any texture to the main structure (the house itself). I would be glad if someone could to help me.

In 3D material view:
The image corresponds to the preview but what is bothering me is that the whole structure is affected and i can't obviously have a different material for different parts of the structure. AND the UV editor shows the "right" texture for the selected face.

In rendered view:
It still looks the same like in the image above in my original question.
Texture view:
Also still the same.
So, what did i do wrong?
By the way, here is the file:

I would suggest watching the 'applying textures' part that you skipped when watching the tutorial.

Are you using Blender Internal or Cycles?

I'm using blender render. And i checked the tutorial already. It was some weird stuff about exporting uv maps, editing them in a picture program and stuff like that... since i don't have a picture program it's quite pointless. and there was nothing about my problem either.

I just figured out that if i select for example the chimney and try to apply a texture/material to it, it applies it to the whole structure (while i*m in in 3D material view).

Please consider using http://blend-exchange.giantcowfilms.com/ At least give us screenshots :)

Your object uses only 1 material and 1 texture. Hence it can show only 1 texture while rendering. It works in Texture shading because Blender Internal uses face textures to show images on the selected faces of the mesh. I suggest you look into tutorials about assigning different materials and textures in BI.

See http://blender.stackexchange.com/questions/5203/how-do-you-apply-a-texture-to-select-faces-of-a-mesh and http://blender.stackexchange.com/questions/6534/render-not-showing-uv-texture

Found the problem!
Some faces overlap and causes some rendering problems. Go into Edit Mode and move some of the faces away from its overlapping part.
Note: Since you didn't give me a texture to work with, I simply used my own...

Another solution: Remove Doubles (Press "w"), but this will make you have to unwrap some faces again.
Nice house by the way!
Another problem: The overlapping faces that are causing render problems isn't properly unwrapped:

I'm assuming you know how to unwrap, so go ahead and do that!
P.S: Select everything in Edit Mode and press ctrl + n. This will recalculate the normals and make you feel more organised ;)
Happy Blending!

Cool, I'll try to do that. Thanks a lot! :)

No problem! If it was helpful, please upvote!


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Extruding surface while keeping the shape
here is the picture of what I would like to get(example nr. 2). I need the edge frame to be same in width and length. Also the extrusion is on surface (without depth) I tried extruding region, but it did not give me the result I wanted.
 I know I could just adjust the scale and do it manually, but that would be eyeballing without achievign accuracy. I would like to know if it is possible to extrude or inset while keeping the shape (even edge space)

Related -http://blender.stackexchange.com/questions/21107/can-shapes-with-rounded-corners-be-extruded-with-even-thickness

Inset the face

Go into edit mode. Select the face. right-click
Press I to inset the face.

OR

Press W to open the Specials menu.
From the Specials menu, choose Inset Faces. I

OR

PressCtrl+F to open the Faces menu.
From the Faces menu, choose Inset Faces. I

OR

Choose Mesh > Faces > Inset Faces from the edit mode menu.

With the object selected in Object Mode. Press "Ctrl+A" and click "Scale" to apply the any scaling operations you performed in Object Mode. Now in Edit Mode, select the plane and press "I" to inset it.


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Is there any other way without array modifier?
I am looking for a way to model circular objects without array modifier. Something like this for example:

Edit: as you can see the dimensions tab has numbers. I think that is what's messing the mesh around. Have I modelled my basic part incorrectly ? Is there a way to reset the dimensions of an object?

Why do you wanna avoid array modifier if it only improve your workflow and save you time?

because in my case I  have dimensions not equal to zero so I am getting distortions. This is with the transformation and rotation applied, but i have altered dimensions that I cannot clear

dId not understand your issue with "not equal to zero" are you saying that your model has a distortion and the "Wheel" is not a perfect circle?

Remodelled my mesh and did everything from the beginning. It worked. Would be helpful to know how to reset the dimmensions though.

Your scale is correct ... they are all 1.0, this means that you have not altered your dimension in any way after you created the object. What do you mean you cannot clear the dimension? The dimension is an imaginary bounding 3-dimensional box around your model. If you change the value in the dimension ... you will notice that scale factor also changes depending on the amount you stretch your model in respective axis.

Yes, indeed. I misunderstood the workings of the array modifier. It is clear to me now. This should be deleted. Thanks for the replies hawkenfox. Got some information from your last post.

Maybe you can use both X and Y symmetry in the mirror modifier.
Like so..

It does depend on the complexity of your subject. In many cases Array will give you more control than the mirror modifier but for less complex objects this may be helpful.


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How to fix a disappeared addons tab in user pref. menu?
I was watching a video on how to script an addon. When I loaded my script, the addons tab menu disappeared. In the script in the bl_info properties I deleted the

"warning": "",
"wiki_url": "",
"category": "Add Mesh",

I have tried reloading factory settings, but it did not help. I know reinstalling probably would help, but isn't there another way ?

This is the script I used for adding an object into the scene:
bl_info = {
    "name": "Head mesh",
    "author": "sensim",
    "version": (1, 0),
    "blender": (2, 78, 0),
    "location": "View3D > Add > Mesh > Basic head mesh",
    "description": "Adds a new basic head mesh"

    }

import bpy
from bpy.types import Operator
from bpy.props import FloatVectorProperty
from bpy_extras.object_utils import AddObjectHelper, object_data_add
from mathutils import Vector

def add_object(self, context):

    verts = [Vector((-1.1349272727966309, -1.7702020406723022, -1.0)), Vector((-1.0, -1.0, 0.7697991132736206)), Vector((-1.1349272727966309, 1.7702020406723022, -1.0)), Vector((-1.0, 1.0, 0.7697991132736206)), Vector((1.1349272727966309, -1.7702020406723022, -1.0)), Vector((1.0, -1.0, 0.7697991132736206)), Vector((1.1349272727966309, 1.7702020406723022, -1.0)), Vector((1.0, 1.0, 0.7697991132736206)), Vector((0.34025609493255615, -0.34025609493255615, -0.19741106033325195)), Vector((-0.34025609493255615, -0.34025609493255615, -0.19741106033325195)), Vector((-0.34025609493255615, 0.34025609493255615, -0.19741106033325195)), Vector((0.34025609493255615, 0.34025609493255615, -0.19741106033325195)), Vector((1.0, -1.0, 1.5482919216156006)), Vector((1.0, 1.0, 1.5482919216156006)), Vector((-1.0, 1.0, 1.5482919216156006)), Vector((-1.0, -1.0, 1.5482919216156006)), Vector((0.6152846813201904, -0.6152846813201904, 2.309370517730713)), Vector((-0.6152846813201904, -0.6152846813201904, 2.309370517730713)), Vector((0.6152846813201904, 0.6152846813201904, 2.309370517730713)), Vector((-0.6152846813201904, 0.6152846813201904, 2.309370517730713)), Vector((1.0, 0.308607816696167, 0.7697991132736206)), Vector((1.0, -0.308607816696167, 0.7697991132736206)), Vector((0.839706540107727, -0.2591400146484375, 0.5348026752471924)), Vector((0.839706540107727, 0.2591400146484375, 0.5348026752471924)), Vector((1.0, -0.308607816696167, 1.5482919216156006)), Vector((1.0, 0.308607816696167, 1.5482919216156006)), Vector((0.8649244904518127, 0.2669224739074707, 1.8155105113983154)), Vector((0.8649244904518127, -0.2669224739074707, 1.8155105113983154)), Vector((1.6463451385498047, 0.308607816696167, 0.7697991132736206)), Vector((1.6463451385498047, -0.308607816696167, 0.7697991132736206)), Vector((1.6463451385498047, -0.308607816696167, 0.9704011678695679)), Vector((1.6463451385498047, 0.308607816696167, 0.9704011678695679)), Vector((0.9206359386444092, -0.5034536123275757, 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1.769901990890503)), Vector((0.6621315479278564, 0.49928683042526245, 1.7157901525497437)), Vector((1.0, -0.6543039083480835, 1.5482919216156006)), Vector((1.0, -0.6543039083480835, 0.7697991132736206)), Vector((0.7401045560836792, -0.44110357761383057, 2.0624403953552246)), Vector((0.7401045560836792, 0.44110357761383057, 2.0624403953552246)), Vector((1.0, 0.6543039083480835, 0.7697991132736206)), Vector((0.5899813175201416, 0.2996980547904968, 0.16869580745697021)), Vector((1.0, 0.6543039083480835, 1.5482919216156006)), Vector((0.5899813175201416, -0.2996980547904968, 0.16869580745697021)), Vector((0.9319220781326294, -0.6377922296524048, 1.7014949321746826)), Vector((0.7940413951873779, -0.5443528890609741, 1.9580446481704712)), Vector((0.8146589398384094, 0.5022628307342529, 1.9149503707885742)), Vector((0.9254456162452698, 0.5931446552276611, 1.6957820653915405)), Vector((0.6621315479278564, -0.569290280342102, 1.7157901525497437)), Vector((0.6095027923583984, -0.526117205619812, 1.8199052810668945)), Vector((0.6095027923583984, 0.526117205619812, 1.8199052810668945)), Vector((0.6621315479278564, 0.569290280342102, 1.7157901525497437)), Vector((0.457908034324646, 0.1799527108669281, -0.02492871880531311)), Vector((0.457908034324646, -0.1799527108669281, -0.02492871880531311)), Vector((0.7220546007156372, 0.1370525062084198, 0.36232033371925354)), Vector((0.7220546007156372, -0.1370525062084198, 0.36232033371925354)), Vector((0.5899813175201416, 0.15850260853767395, 0.16869580745697021)), Vector((0.5899813175201416, -0.15850260853767395, 0.16869580745697021)), Vector((0.7715945839881897, 0.1799527108669281, -0.013859517872333527)), Vector((0.7715945839881897, -0.1799527108669281, -0.013859517872333527)), Vector((0.6496176719665527, 0.15850260853767395, 0.1365136206150055)), Vector((0.6496176719665527, -0.15850260853767395, 0.1365136206150055)), Vector((0.3584824204444885, 0.1370525062084198, 0.3188619315624237)), Vector((0.3584824204444885, -0.1370525062084198, 0.3188619315624237)), Vector((0.22640913724899292, 0.15850260853767395, 0.12523742020130157)), Vector((0.22640913724899292, -0.15850260853767395, 0.12523742020130157)), Vector((0.8025145530700684, -0.35401302576065063, 1.93897545337677)), Vector((0.8100641965866089, -0.428521066904068, 1.8883529901504517)), Vector((0.6221407651901245, -0.5084813833236694, 1.7949036359786987)), Vector((0.8025145530700684, 0.35401302576065063, 1.93897545337677)), Vector((0.841262698173523, 0.46513837575912476, 1.8623204231262207)), Vector((0.6221407651901245, 0.5084813833236694, 1.7949036359786987))]

    edges = []
    faces = [[9, 1, 3, 10], [10, 3, 7, 11], [53, 52, 20, 23], [8, 5, 1, 9], [2, 6, 4, 0], [2, 10, 11, 6], [3, 1, 15, 14], [0, 9, 10, 2], [4, 8, 9, 0], [14, 15, 17, 19], [7, 3, 14, 13], [6, 11, 8, 4], [81, 78, 27, 26], [1, 5, 12, 15], [16, 18, 19, 17], [15, 12, 16, 17], [13, 14, 19, 18], [48, 49, 21, 24], [23, 20, 21, 22], [20, 25, 31, 28], [24, 25, 26, 27], [52, 54, 25, 20], [53, 23, 66, 68], [81, 26, 38, 82], [49, 55, 22, 21], [24, 27, 37, 32], [29, 28, 31, 30], [24, 21, 29, 30], [21, 20, 28, 29], [25, 24, 30, 31], [38, 39, 47, 46], [82, 38, 46, 83], [26, 25, 39, 38], [16, 12, 33, 34], [48, 24, 32, 56], [54, 13, 36, 59], [50, 16, 34, 57], [13, 18, 35, 36], [51, 81, 82, 58], [58, 82, 83, 62], [36, 35, 43, 44], [56, 32, 40, 60], [59, 36, 44, 63], [57, 34, 42, 61], [32, 37, 45, 40], [34, 33, 41, 42], [79, 57, 61, 80], [39, 59, 63, 47], [33, 56, 60, 41], [37, 79, 80, 45], [27, 78, 79, 37], [78, 50, 57, 79], [25, 54, 59, 39], [12, 48, 56, 33], [35, 58, 62, 43], [5, 8, 55, 49], [18, 51, 58, 35], [22, 55, 69, 67], [7, 13, 54, 52], [12, 5, 49, 48], [18, 16, 50, 51], [11, 7, 52, 53], [67, 69, 77, 75], [69, 65, 71, 73], [55, 8, 65, 69], [23, 22, 67, 66], [11, 53, 68, 64], [8, 11, 64, 65], [71, 70, 72, 73], [68, 69, 73, 72], [64, 68, 72, 70], [65, 64, 70, 71], [77, 76, 74, 75], [66, 67, 75, 74], [69, 68, 76, 77], [68, 66, 74, 76], [51, 50, 78, 81]]

    mesh = bpy.data.meshes.new(name="New Object Mesh")
    mesh.from_pydata(verts, edges, faces)
    # useful for development when the mesh may be invalid.
    # mesh.validate(verbose=True)
    object_data_add(context, mesh, operator=self)

class OBJECT_OT_add_object(Operator, AddObjectHelper):
    """Create a new head mesh object"""
    bl_idname = "mesh.add_basic_head"
    bl_label = "Add head mesh object"
    bl_options = {'REGISTER', 'UNDO'}

    def execute(self, context):

        add_object(self, context)

        return {'FINISHED'}

# Registration

def add_object_button(self, context):
    self.layout.operator(
        OBJECT_OT_add_object.bl_idname,
        text="Add head mesh object",
        icon='PLUGIN')

# This allows you to right click on a button and link to the manual
def add_object_manual_map():
    url_manual_prefix = "http://wiki.blender.org/index.php/Doc:2.6/Manual/"
    url_manual_mapping = (
        ("bpy.ops.mesh.add_object", "Modeling/Objects"),
        )
    return url_manual_prefix, url_manual_mapping

def register():
    bpy.utils.register_class(OBJECT_OT_add_object)
    bpy.utils.register_manual_map(add_object_manual_map)
    bpy.types.INFO_MT_mesh_add.append(add_object_button)

def unregister():
    bpy.utils.unregister_class(OBJECT_OT_add_object)
    bpy.utils.unregister_manual_map(add_object_manual_map)
    bpy.types.INFO_MT_mesh_add.remove(add_object_button)

if __name__ == "__main__":
    register()

edit2: also getting this error message if i try the script.

Please provide the script that leaded to this happening

Please paste the script here http://pasteall.org/ as the link you provided required signup and no one here will do this as you need to help others help you

what OS are you using and what blender version are you using as well?

Blender 2.78 in Windows 10

Same, I'm using the same version and win7. Please download blender from here http://mirror.cs.umn.edu/blender.org/release/Blender2.78/blender-2.78a-windows64.zip and install your script and see if it is working

tried reinstalling and also tried using this zipped version none helped

so could you please say the detailed steps you did after downloading the folder from the link I sent you?

I unzipped it and opened it. Then I went to user preferences menu and then the addons submenu.

I have found out that it is a bug. There is no other way to fix this unless you reinstall blender. After you uninstall you must also delete all the registry entries (windows button + R -> regedit -> edit -> find -> look for "blender" -> delete all found blender related entries ). Also delete all the left over data from '\program files', '\documents'. Then in file explorer fileline enter '%appdata%' and check for Blender file left overs. Delete them if you find any. Then install blender again. Don't forget to save your preferences and keybind configs!

I tried installing the script and it worked for me as shown below and I still have the addons showing in the user preferences. Try to download blender from here and install your script and it should work.

perhaps I need to delete the registry files or everything Blender related in my computer, because neither using the version you've provided neither uninstalling and installing helps ?

@Sensimas so when you downloaded the folder then opened blender then user preferences nothing was in the addon tab? Even without running the script?

That is right. It was a blank window with or without script. Also when I tried opening the script, I got an error message ( picture in the first post)

Do not delete Blender, go to your %appdata% folder and to this path
C:\Users\[INSERT USER ACCOUNT HERE]\AppData\Roaming\Blender Foundation\Blender\2.79\scripts\addons

and delete the offending script, reload Blender or hit refresh and it should come back.


text:
Is there really no way to add edge loops with maintaining geometry?
I often come into situations where I would need more geometry when modeling using subdivision surface. Maya has a tool for that. It works by adding edges by subdividing but still maintaining the form of the mesh. Here is a link showing how it works:
 https://www.youtube.com/watch?v=qVX_II7VQxI&t=130s
Here is a picture hopefully clearing my question:

ctrl + r???????

This: https://blender.stackexchange.com/questions/13545/is-there-a-tool-similar-to-mayas-edit-edge-flow-in-blender?rq=1 might also help

I don't think this is a duplicate: the question isn't about how to add edge loops, but how to add them in a way that they don't change the surface when working with subsurf. Normally, edge loops with subsurf make the edges sharper which isn't always intended. (Note that the subsurf modifier is just an easy way to visualize the effect)

@Sensimas If the duplicate question isn't what you meant then you need to [edit] your question and add additional details to explain how your question differs.

This is NOT duplicate, watch the video linked.

The last shape was adjusted manually (not mathematically) so it differs from the first one, but the idea is to add geometry while the shape remains the same when subdivided. The tool is creating new geometry to match the original geometry  with edges right where you need them.

I have not found any information on the web regarding that sort of tool in Blender therefore I conclude it does not exist. However I think the workaround might work in some situations depending on your needs. Here is what I used:

select your mesh
alt +c (convert to) -> mesh from curve/meta/subd/text
cleverly use the edges you need for your shape and remove the ones that does not affect it

Hope it helps.


text:
how to make viewport display diffuse maps in full color? (2.8)
I am  painting textures onto 3d meshes so I need to see the color exactly as it is, but in texture paint mode my colors are 100% bright (white is 100%), but in viewport colors get as if it was in lower light (white is like 80%ish grey).
How to make viewport display diffuse maps in full color (like displayed in textures) ?
flat shading is on, still no result.

Try setting viewport Overlays -> Texture paint Opacity to 0.

Managed to experiment the solution out. Here's how:
Rendering tab (evee rendering selected) -> color management -> display device (set to REC709)

I had this issue but with Vertex Color insted. I realized if I set Viewport Shading to "Texture" instead of "Vertex" it displayed full brightness. If anyone needs this info.


text:
Is there a way to bake materials/textures, that use nodes, into materials/textures that can be used in the game engine?
I am using some fairly irregular shapes, and most of the tutorials I have found have been about baking cubes or rectangular prisms, and I can't get that to work with my shapes, or have been about Blender Render. The objects that I wish to bake are pictured below.

It is supposed to be a building, and there are two rectangular prisms joined to make it. The prisms have been aligned face to face and edge to edge so I know there is no gap or anything between them. The same goes for the door and door frame. The top of the larger of the rectangular prisms has a knife project on it so I can easily remove a section of it and add things on the inside of the building. There is nothing inside it yet as I want to bake it first.
Thanks in advance to anyone who helps, and if there is any information you might need that I have not supplied please tell me.
UPDATE: I tried the solution offered by @pycoder and I got an error saying that there is no active image found in one of my materials. Is this something that is required for baking?

see this other answer for more info and examples: http://blender.stackexchange.com/questions/13508/how-do-i-bake-a-texture-using-cycles-bake

also if your room is completely closed, add a new lamp inside like point or area, with enough power to illuminate your "room"...

Nothing really changes from a rectangular baking tutorial to anything else except for the UV mapping. Try using "Smart UV Project" to unwrap a complex object quickly, then go through the baking steps.

Add the image texture that you want to bake to in all of your materials (on the object that you are baking).
Setup the bake settings (depending on what you want to bake), then hit the bake button.
Save the baked image.

Okay so I just tried that, and I got a much better unwrap than before (actually its perfect now). However I got an error saying there is no active image found in one of the materials. Is there a way to bake without needing an image reference? Or is there a way to use an image without distorting the material? Is this something I should create a new question for?

Every material needs an image in it, but it shouldn't "distort" your material. It just needs to be sitting as the active node somewhere, not connected to anything else or contributing to the material in any other way. The "baker" will find the active texture and know where to bake to.


text:
Glass - How to make visible light source behind (eevee)
I'm trying to build a simple metro train. My goal is to make the windows transparent so I can see from the inside the lights that are out of the train. I tried to play around with the settings that are within the Glass shader but I cannot do it. I get the effect only on the outer side. Im a newbie.
This is from the inside:

This is from the outside:

As you can see I get a reflection which I dont want. I want only the glass to be transparent from both sides.

maybe this will help? https://blender.stackexchange.com/questions/148559/how-to-hide-lamp-reflection-in-eevee

Basically add texture/material to the glass object.

You have transparent glass if you can see inside. From outside you see black because of black environment, but you have invisible the light behind the glass, right? I changed title. If Im wrong change it back. Thank you

Light source behind a glass (Eevee)

To see through a glass enable

Properties editor > Render Properties tab > Screen Space Reflections > Refractions
and under Material Properties > Settings > Screen Space Refraction

To see a light source like a Point

add a Cube (in location of light) with Principle Volume shader
decrease Density to 0.1 or lower and Anisotropy increase to 0.9

Thank you all! Gonna try your solutions.

If the answer solved your issue consider mark it as accepted (grey big checkmark under vote arrows), it is only your privilege to do and you can uncheck any time too. It is useful for others to see it from main list it was solved. Thank you


text:
Export particle system to meshes (stl/obj whatever) without converting
I'm trying to create rubble-pile objects for a simulation. My simulation code can import STLs or OBJ files. These rubble-piles need to be made of many smaller constituent meshes that follow a certain size distribution. See my image where the number of smaller objects is much greater than that of the large objects.

I have a particle system that uses an object collection to fill a volume (in this case, the Itokawa surface mesh), and I may at times need 50,000+ particles/objects. Blender has no problem generating this distribution, and does so basically instantly. But if I want to export it, I have to convert all 50,000+ particles to instanced meshes first, and this either A) takes forever, or B) crashes Blender. It also makes exporting 50,000 objects to a single file a major chore. Is there some way, possibly with scripting, to just stream the particle system straight to an exported mesh file without having to create instanced objects in the object tree (or without having to create every instanced object all at once)? Or does anyone know when something like this can be done with Geometry Nodes that acts like a modifier (since the export applies modifiers upon export)?
I have found that if I create a second object and give it the modifier of "Particle Instance" and point it to the main object that has the particle emitter, I get half of what I want, in the sense that it is an exportable collection of instanced objects, but the instanced objects are all just clones of the object with the modifier and doesn't respect the size distribution.

BTW if you want to let us inspect your file share it via https://blend-exchange.com with only objects needed to reproduce your issue.

OK ... Have you tried Alembic export ... or decimate rubble-pile instances low-res before export... Or to use geo nodes instead?  I'm not sure we can help... We don't know how dense elements are ... Even you will share your file we use different hardware processing power so it wouldn't be easy say what could work for you.


text:
Is there a way to automatically discard shapekey "offsets" for individual verts, based on their difference to basis?
I know this is the sorta thing you'd usually code up with a simple script, but I'm absolutely python illiterate.
As far as I understand, shapekeys internally store their offset to basis when they're relative. However, over time I feel like a lot of my shapekeys have become "messy".
In the sense that a lot of vertices that aren't VISUALLY affected by a shapekey, still are moving a tiny amount, which within blender rarely causes issues but in other workspaces can cause minor normal shifts- Which is obnoxious at best.
I wonder if its possible to write a script that effectively goes through all shapekeys, and if a given vertex' "offset vector"(?) is less than a threshold, it gets clipped back down to 0.

Try this code. I set the threshold to 0.1m so that means if the vertices differ by only less than 0.1m, then it will set it back to the same position as in basis. Feel free to change it to another value. It then goes on to iterate through all shape keys except the basis and compares all vertices to the basis using your threshold value.
import bpy

threshold = 0.1

obj = bpy.context.active_object
mesh = obj.data
basis_key = mesh.shape_keys.key_blocks[0]

for key in mesh.shape_keys.key_blocks[1:]: # loop through all shape keys except the basis
    for i, vert in enumerate(mesh.vertices): # loop through all vertices
        diff = key.data[i].co - basis_key.data[i].co
        if diff.length < threshold:
            key.data[i].co = basis_key.data[i].co


text:
Blender Cycles: baked texture Render black
as the title says, all my texture render as if there is no light. ive added planes w/ emissions, sun,spot ect. to no avail. im using blender 2.93 and a very low poly mesh. with a mixed shader (Diffuse and Glossy). here is what it produces.

Seems to me like switched face Normal orientation ... you are baking inside of bag.

No ive even double checked by flipping faces

Please share your file via https://blend-exchange.com because it looks exactly like that ... btw did you selected Image texture node before baking?

 here is the file. and yes i selected Image texture node before baking @vklidu

Thanks ... next time please insert code into your Q via edit :)

You are right, your normals are oriented right, but your UVmap shares same place for outer and inner faces ... this caused your issue. You probably created models as single sided, unwrapped and added/applied Solidify = same UV for original unwrap and newly generated faces of Solidify.
You would have to separate them in some way ...

fastest - just create another UVMap layer - unwrap as Smart UV Project and add Image Texture node with the same newly created image into each material

Thank you ill try that and update

Update:  Thank you vklidu, i removed the  Solidify unwrapped Smart UV and it worked perfect.


text:
Created concrete material by following a 2.79 tutorial in 2.8 and messed up true displacement
Here's the tutorial I followed:
https://youtu.be/wmtAVNDtc_w
The only change I made was i skipped a portion with the image texture around 5:30 because i didn't find any major change without it and he youtuber didn't provide any link for the image. So now I'm left with a mesh that ignores true displacement in eevee and takes it too far in cycles
here are some screens links as the page isnt allowing me to upload them directly:
https://photos.app.goo.gl/FPrTejKkSQqiCWVdA
And here is the blender file:

What's your question? You haven't asked anything. Be specific if you wish a specific answer.

I want to fix the messed up mesh that I'm left with, check out those screens to understand the situation

please share your file: https://blend-exchange.giantcowfilms.com/

You can post images so they are shown with your question so people can see them straight away instead of clicking on a link. If you make it hard for people to help you, there is less chance for you to get the help you wish to get. It's best to follow the format of the platform as much as possible. You should also describe what you think is wrong in the images, what the desired results are and how the results you get differ from them.

i understand that sir, but for some reason the page doesn't respond to submit whenever i try to upload one directly

Due to adding vector displacement not so long ago to Blender you have to use dedicated displacement node to convert scalar to vector displacement.

I would say that your shader structure is outdated. It is better to mix RGBs instead of shaders, and use Principled BSDF instead of mixing Diffuse and Glossy. Take a look at the blend file. Although this is not the best example to demonstrate the superiority of the approach, I changed it so it would reflect the idea without altering the artistic component. The shader became heavier but more realistic and PBR.


text:
Modelling cell division in blender
I want to make an animation where a simple cell divides into two but how could I animate that Morphy or glooby division (organic not simple cutting into two halves or duplicating like copy and paste)? I have seen a lot of tutorials using metal balls but they are too rigid and cannot be modified to a great extent like meshes.
Edit like this video https://www.youtube.com/watch?v=FvgEaDVCKfA&feature=youtu.be#t=1m52s

@JachymMichal I am not asking about how to make a cell I am asking about how to make the glooby and morphy-like division

Sorry, my bad. In that case I'd also stick to metaballs, but I'm in no way expert on this. Good luck.

you should picture of what you want, is it realistic or not, etc...

you linked to a 4:50 video, could you [edit] your answer to point out where does the animation you want occurs?

The part where carcinogenic cells start division at 1:52

Yes metaballs are perfect for this purpose

Here may be an alternative to Metaballs, I remember seeing something similar done with 3DS Maxs symmetry modifier so I attempted to try something with Blenders mirror modifier in combination with other modifiers.

On your mesh that you want to split go into edit mode and select some vertices where you want there to be tension during the animation and apply a hook modifier then a mirror modifier (use a empty for your mirror modifier origin) and then apply some smooth and sub D modifiers towards the end. Maybe the animation can be baked and then soft body dynamics could be applied but I've never tried that though, just a thought.

Good answer but the original problem persists because we want the new meshes not to mix with each other but unfortunately they will mix again after separation

What you are trying to accomplish sounds like it would require multiple techniques and hacks to get the correct end result, or you made need to look into a more procedural approach. Metaballs is probably your best option if this is for  some sort of medical animation. Maybe check out the Animation Nodes add-on

how did you animate it? i cannot recreate the effect unless in edit mode

The empty connected to the hook modifier is keyframed to help create the pull apart effect.

As Jachym says, you should use metaballs.

ShiftA to create a metaball, call it for example A. Give it a material with a bit of noise. To increase its resolution, decrease the Resolution value in the Properties panel > Object Data > Metaball. Duplicate it, it will be called A.001, as you can see A.001 will merge with A.

If you want to make metaballs that won't merge with others, just duplicate a metaball and give it a different prefix, like for example "B" (but don't give it any suffix). Duplicate B. B and its copies won't merge with A and its copies, it will only merge with B and its copies.

In your video, the cells behave a bit like softbodies, as I don't see how you could mix metaballs and softbodies, what you could do to fake this effect is gather 3 metaballs, keep them together as if they were one object and make them bounce a bit. Maybe someone will have a better solution...

Very good answer but I want also the formed or new cell (metaball that appears after merging) not to mix or merge with the original cell after separation.

mmh you're right, not easy

anyway you have teached me a new blender trick. I think the answer may involve some python codes.However, as a trial you can change the stiffness of the metaball from active element settings and this might partially solve the problem but still the metaballs will not be able to bounce over each other or stand on each other.

Thanks for this, I've been wondering how to create an extra set of Metaballs that would not merge with others in the same scene.


text:
What would be some approaches to get low noise images from cycles with given render time for indoor scenes?
For an animation of 10k frames I would like to find a tradeoff between render time and quality. With a given approximately render time of 1 minute per frame it would take 167 hours (a week, 24h per day) to render the full animation.
For outdoor scenes I simply increase the number of samples to achieve this.
For indoor scenes I use the Limited Global Illumination preset plus Ambient Occlusion and fiddle around the distance slider until the image looks 'bright enough'.

The lighting test scene has transparent windows, some emitting planes.
The results are:
with 50 samples (3 minutes):

with only 20 samples a lot more noise (~1 minute)

Which settings should be taken into account when trying to reduce noise for a given render time?
Completely different approaches are also appreciated.

Reduce max bounces to 4(you don't need more), Use filter glossy to maximum. Use like 50-75 samples. Try to avoid using roughness(it makes a lot of noise). Make object Mix shader and put shader in bottom, than set the factor. There are a lot more suggestions which should help.
Here
are some more things to use.


text:
Where can I change mixing of an action in NLA?
I combined two action strips in the NLA-editor but the forward movement fades in (red curve in the image below)  I would prefer to have this linear. Where can I change this behaviour? Action blending and extrapolation doesn't seem to have an effect.

The relevant setting is Blend In/Out. To ignore keyframes in strips below the active one, turn off Auto Blend In/Out, and set both blend values to 0:

More generally I suggest, for bones that will be animated in a layer, to avoid keyframing it in strip actions in all other layers. Or do it in such a way that the strips don't overlap. That'd save you some headache when the animation mixing gets more complex, especially if there are semi-overlapping action strips. Not used carefully, action blending could cause jerky movement that's hard to tweak.


text:
What do the bars between keyframes mean?
Between some keyframes a bar is drawn, when is a bar displayed?

This means that the keyframes which the bar connects are the same.
From the manual:

When the value of a given channel does not change at all between two neighboring keyframes, a gray (unselected) or yellow (selected) line is drawn between them.

E.g. If you insert a LocRot keyframe on frame 1, then rotate and insert another LocRot keyframe on frame 10, the Location will not have changed so there will be a bar drawn between each location channel keyframe:


text:
Normal baking corner problem
Good evening!
I've looked at other similar topics but none resolved my issue.
The problem is corners after baking normals and applying them to a mesh.
Both cubes have same amount of bevel.
I have subdivided only 5 large square faces and sculpted them for the High res. cube.
Unwraped with smart UV
What could be the problem?

Problem looks similar to this: http://blender.stackexchange.com/questions/53025/rendered-texture-looks-messed-up/53146#53146
But the normal is already non-color.

Try increasing Margin in the Bake options for normal map (if it wasn't already).

Tried margin of 0, 3, 16, 64 .. Doesn't help..

Does the mesh have doubles / any not expected geometry ? Also make sure that UV map islands don't intersect and have enough space between them. Maybe upload it and add a link here

@Mr Zak Thanks for Your time! Here is the project:

Well, problem is definitely not the non-color data.. rather than the topology of your high-poly mesh, and maybe UV map for the low-poly cube. I'm really unaware how that cube can make Smart UV Project fail like it does, but anyway big faces of your cube intersect with bevels (not desired), although the main problem is high-poly I will try to elaborate in answer if it goes well

The problem are the ngons with 124 vertices/edges on the high res cube.

Adding a triangulate modifier to the cube solves that issue.
Also, the front and bottom faces of the low res cube are overlapped in the UV, so you should unwrap it again.


text:
Size of fluid increasing with no understandable reasons
Initial volume:

After rotating, size of fluid became bigger:


text:
How to show open dialog box that can navigate to blender datablocks
How to show open dialog box that can navigate to blender datablocks.
I can show open dialog that can select .blend files, but how to select specific datablock just as 'File->Link' or 'File->Append' does?
Below is the code I am using ( copied from template ):
def read_some_data( context, filepath ):
  print("running read_some_data...")
  print( filepath )
  return {'FINISHED'}

class ImportSomeData( Operator, ImportHelper ):
    bl_idname = "import_test.some_data"
    bpy.ops.import_test.some_data is constructed
    bl_label = "Import Some Data"

    filename_ext = ".blend"

    filter_glob = StringProperty(
        default="*.blend",
        options={ 'HIDDEN' },
        )

def execute(self, context):
    return read_some_data(context, self.filepath)

Thanks!

The question I would ask in response to this is why you would want to do this, if the feature already exists? I presume you want to access data blocks from code, rather than a visual interface, then?

No @MaVCArt, if you have a question, ask it in a different thread lol :p Let programmers be programmers, that's why we have the internet in the first place ^_^. My boss said I couldn't reasonably render 11 billion points in a browser application. I didn't even have to prove him wrong! (see potree) Anyways, hovering over the append/link commands exposes the python code executed when you click them. I LOVE LOVE blender for this epic use of open source tooltips. Turns out your question has already been answered here:
http://blender.stackexchange.com/questions/3

You need to use bpy.data.libraries. The class has a function load which read the datablock of a blend file.
Here an example of how to draw such dialog box to append either a group or an object.
class open_blend_file(bpy.types.Operator, ImportHelper):
    """Import a .blend file to append model from"""
    bl_idname = "blend.open"
    bl_label = "Import"
    bl_options = {'UNDO'}

    filter_glob: StringProperty(
        default="*.blend",
        options={'HIDDEN'},
    )

    group: BoolProperty()

    def get_lib_groups(self,context):
        l = [];
        if os.path.exists(self.filepath) and self.filepath.endswith('.blend'):
            with bpy.data.libraries.load(self.filepath) as (data_from, data_to):
                groups = data_from.groups;
                # objects = data_from.objects;
                for g in groups:
                    l.append((g,g,g));
        if len(l) == 0:
            l = [("None","None","None")];

        return l;

    def get_lib_objects(self,context):
        l = [];
        if os.path.exists(self.filepath) and self.filepath.endswith('.blend'):
            with bpy.data.libraries.load(self.filepath) as (data_from, data_to):
                # groups = data_from.groups;
                objects = data_from.objects;
                for o in objects:
                    l.append((o, o, o));
        if len(l) == 0:
            l = [("None","None","None")];

        return l;

    lib_groups: EnumProperty(
        name = "List of groups in the .blend file",
        description = "List of groups in the .blend file",
        items = get_lib_groups
    );

    lib_objects: EnumProperty(
        name = "List of objects in the .blend file",
        description = "List of objects in the .blend file",
        items = get_lib_objects
    );

    def draw(self, context):
        scene = bpy.context.scene;
        props = scene.property;
        layout = self.layout;

        row = layout.row();
        row.prop(props,'import_from', expand = True)

        if props.import_from =='Groups':
            if len(self.lib_groups)>0:
                row = layout.row();
                row.prop(self,'lib_groups', text = "Groups", icon = "GROUP")
        else:
            if len(self.lib_objects)>0:
                row = layout.row();
                row.prop(self,'lib_objects', text = "Objects", icon = "OBJECT_DATA")

    def invoke(self, context, event):
        context.window_manager.fileselect_add(self)
        return {'RUNNING_MODAL'}

    def execute(self, context):
        if self.group :
            name = self.lib_groups;
        else:
            name = self.lib_objects;

        if self.group:
            blend_file = self.filepath + "/Group/"
            bpy.ops.wm.append(directory=blend_file, link=False, filename=name, autoselect = True);

            group = bpy.data.groups.get(name);
            if group is not None:
                bpy.ops.object.empty_add(type='PLAIN_AXES', location = (0,0,0));
                obj = get_active_object();
                obj.name = group.name;

                for o in group.objects:
                    o.parent = obj;

                group.objects.link(obj);

        else:
            blend_file = self.filepath + "/Object/"
            bpy.ops.wm.append(directory=blend_file, link=False, filename=name, autoselect = True);

        return {'FINISHED'}

What does scene.property look like? I get the error:
AttributeError: 'Scene' object has no attribute 'property'

Ahh, got it. 'propterty'  can be  a PropertyGroup with a StringProperty 'import_from'.

It seems there is now way to bring this dialog box that Append and Link are using.
I've wrote some custom append operator by reworking the code from the previous answer, hope it will be useful.
import bpy
import os

bl_info = {
    "name": "Blender Custom Append",
    "author": "@Andrej730",
    "version": (1, 0),
    "blender": (2, 90, 0),
    "location": "",
    "description": "",
    "warning": "",
    "category": ""
}

def append_data_block(filepath, data_block_type, name, link=False, relative=False):
    with bpy.data.libraries.load(filepath, link=link, relative=relative) as (data_from, data_to):
        if name not in getattr(data_from, data_block_type):
            return {
                "data_block": None,
                "msg": f"Data-block {data_block_type}/{name} not found in {filepath}"
            }
        getattr(data_to, data_block_type).append(name)
    return {
        "data_block": getattr(data_to, data_block_type)[0],
        "msg": ""
    }

class CustomBlendAppend(bpy.types.Operator):
    """Import a .blend file to append model from"""
    bl_idname = "blend.custom_append"
    bl_label = "Custom Blend Append"
    bl_options = {'UNDO'}

    filepath: bpy.props.StringProperty(
        name="File Path", description="Filepath used to import from",
        maxlen=1024, default="", subtype="FILE_PATH"
    )

    filter_glob: bpy.props.StringProperty(
        default="*.blend",
        options={'HIDDEN'},
    )

    def invoke(self, context, event):
        context.window_manager.fileselect_add(self)
        return {"RUNNING_MODAL"}

    def get_lib_groups(self, context):
        l = [("0", "", "")]
        if os.path.exists(self.filepath) and self.filepath.endswith('.blend'):
            with bpy.data.libraries.load(self.filepath) as (data_from, data_to):
                for data_block_type in dir(data_from):
                    data = getattr(data_from, data_block_type)
                    if data:
                        item = (data_block_type,) * 3
                        l.append(item)
        return l

    def get_lib_objects(self, context):
        l = [("", "", "")]
        if self.data_block_type != '0' and os.path.exists(self.filepath) and self.filepath.endswith('.blend'):
            with bpy.data.libraries.load(self.filepath) as (data_from, data_to):
                objects = getattr(data_from, self.data_block_type);
                for o in objects:
                    l.append((o, o, o))
        return l

    data_block_type: bpy.props.EnumProperty(
        name = "Data Block Type",
        description = "List of data blocks in the .blend file",
        items=get_lib_groups,
    )

    data_block: bpy.props.EnumProperty(
        name = "List of objects in the .blend file",
        description = "List of objects in the .blend file",
        items=get_lib_objects,
    )

    def draw(self, context):
        layout = self.layout
        layout.label(text="Data Block Type")
        layout.prop(self, "data_block_type", text = "", icon = "GROUP")
        layout.label(text="Data Block")
        layout.prop(self,'data_block', text = "")

    def execute(self, context):
        if self.data_block_type == "0":
            self.report({"ERROR"}, "Select a data block type")
            return {"CANCELLED"}

        if self.data_block == "":
            self.report({"ERROR"}, "Select a data block")
            return {"CANCELLED"}

        if not os.path.exists(self.filepath):
            self.report({"ERROR"}, f"File not found:\n'{self.filepath}'")
            return {"CANCELLED"}

        db = append_data_block(self.filepath, self.data_block_type, self.data_block)
        if not db['data_block']:
            self.report({"ERROR"}, db["msg"])
            return {"CANCELLED"}

        props = context.scene.AppendedDatablockProps
        props.data_block_type = self.data_block_type
        props.data_block_name = db['data_block'].name
        props.blend_filepath = self.filepath
        print(db['data_block'], props.data_block_type, props.data_block_name, props.blend_filepath)

        return {"FINISHED"}

class AppendedDatablockProps(bpy.types.PropertyGroup):
    data_block_type: bpy.props.StringProperty(name="Data Block Type", default="")
    data_block_name: bpy.props.StringProperty(name="Data Block Name", default="")
    blend_filepath: bpy.props.StringProperty(name="Blend Filepth", default="")

def register():
    bpy.utils.register_class(CustomBlendAppend)
    bpy.utils.register_class(AppendedDatablockProps)
    bpy.types.Scene.AppendedDatablockProps = bpy.props.PointerProperty(type=AppendedDatablockProps)

def unregister():
    bpy.utils.unregister_class(CustomBlendAppend)
    bpy.utils.unregister_class(AppendedDatablockProps)
    del bpy.types.Scene.AppendedDatablockProps

if __name__ == "__main__":
    register()
```