text:
frequent crashes and freezes on Linux
My problem
I recently removed gdm3 from my system to switch to KDE Plasma. Since then, the normal blender starter shortcut doesn't work any more; the program appears in the taskbar and, without showing a window, it disappears, leaving no crash report behind.
I can run it in the terminal, but for unknown reasons, it has huge performance issues in the editor. If I try to open a remotely complex scene, it takes between 30 seconds and multiple minutes to open the scene.
In the editor, it runs smoothly as long as I don't do anything. Especially in edit mode of a model (in this case with about 2.500 triangles) it takes a minute to subdivide a single rectangle or add a cube to the mesh.
While those operations were pending, blender is frozen, sometimes it even froze the whole system except for the cursor.
What I've tried
I tried to run blender with debug information (blender --debug --debug-all), but I didn't get any errors or warnings.
I tried to reinstall blender from multiple sources (dnf, flatpak, snap, steam), but it changed nothing. I even installed the Windows version on Steam and ran it through proton, which resulted in the same problem.
Furthermore, I researched a lot, but I didn't come to a solution which changed anything for me.
Observations
I noticed that blender seems to have a limit at 12.5% of CPU usage.
I ran btop and observed the process. It didn't have any memory problems as far as I understood, but it took 12.5% CPU while an operation was running. Btop showed, in the upper left corner of the process details, that it used 100% CPU, which let me think it has some kind of restriction to 12.5%.
Furthermore, I noticed that it always uses one CPU core on 100%, while the others are below 10%; the used core switched during the process, but it was always one doing all the work.
Here is a screenshot of the product details in btop while I'm subdividing a rectangle:

Specs

Blender version: 4.0.2
Windowing system detected by blender: WAYLAND
OS: Fedora 39 ThirtyNine
Kernel: x86_64 Linux 6.7.9-200.fc39.x86_64
Shell: fish 3.7.0
DE: KDE 5.115.0 / Plasma 5.27.11
WM: KWin
CPU: Intel Core i5-9300H @ 8x 4.1GHz
GPU: NVIDIA GeForce GTX 1650 with Max-Q Design
RAM: 15830MiB

It's important to notice, that I didn't have this issue before on the same machine and in the same scenes, so it's likely not hardware related.
Does anyone here have an idea how to fix this problem? Thanks in advance.

Looks like a bug, you could report it using the help menu inside Blender

Hi, TheLinus. This really is a problem for the developers, we're not qualified to test and give definitive advice for problems we can't all reproduce in our own installations. We are here to help as much as we can with the use of the application and its API. So, sorry, this is off topic-on Blender SE. Please make a bug report. (I'm a KDE Plasma user, but X11.. maybe it's a Wayland thing?)


text:
Cycles render glitches
Im having issues with rendering with cycles as the left side of the blade creates some sort of glitch. Any idea what might be causing this?

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

source: Stack Exchange

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

sort: votes


text:
What Do The New Geometry Nodes Pink Colored Rotation Sockets in 4.1 mean?
I was just working on a project and happened to notice that the input to the rotation for the Instance on Points in 4.1 is no longer a blue socket as it was previously. It is now purplish in color, although the Scale socket is still blue.
I wanted to know what this represents.

Previously both Rotation and Scale were blue, as they are vector field inputs. What has changed now? I could not find anything in the manual.

There's a good YT video explaining all the node types and colours in Blender 4.1 here.

@JohnEason That's a really good explanation video! Thanks for sharing. But in the video I couldn't find the information the OP was looking for regarding what the new purple color represented

Introduced in Blender 4.0 there are new Rotation sockets (look for Simpler Rotations), which replace the old blue colored Vector sockets for the specific cases of rotation values.

Functionally they should be the same, but there are now specific nodes to deal with rotation as presented in the manual which make it simpler to work with rotations by specifying axis, angles, or quaternions, rather than vector values.
Existing nodes have since been slowly but surely converted to use the new pink colored socket for operations that deal with rotation, rather than more general vectors. In this instance for:

Distribute Points on Faces
Instance on Points
Rotate Instances
Transform Geometry

As stated in the commit Geometry Nodes: Convert four nodes to use rotation socket

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


text:
Separate selection with python
I'm trying to separate mesh in two parts with a script, I want to "cut" the mesh in a midpoint plane with bisec and than rip the vertices, this part of my script works fine, the problem is when I select all vertices that are above the bisec and perform a bpy.ops.mesh.separate(type='SELECTED'), only the vertex of the bisec was separated from the rest of the mesh, and not all the selection. Instead if I select the verteces manually(in the viewport)  the separate selection works well.

def bisect_and_select_inner_region(midpoint):

if bpy.context.object is None or bpy.context.object.type != 'MESH':
        print("Nessun oggetto mesh attivo selezionato.")
        return

    if bpy.context.mode != 'EDIT_MESH':
        bpy.ops.object.mode_set(mode='EDIT')

    obj = bpy.context.edit_object
    mesh = obj.data
    bm = bmesh.from_edit_mesh(mesh)

    # Perform Bisec
    bpy.ops.mesh.select_all(action='SELECT')
    bpy.ops.mesh.bisect(plane_co=(0, midpoint, 0), plane_no=(0, -1, 0), clear_inner=False, clear_outer=False, use_fill=False)

    original_type = bpy.context.area.type
    bpy.context.area.type = "VIEW_3D"

    # Rip vertices
    bpy.ops.mesh.rip()
    bpy.context.area.type = original_type

    # Select vertex above the bisec
    for v in bm.verts:
        if v.co.y > midpoint:
            v.select = True

    # Separate select
    bpy.ops.mesh.separate(type='SELECTED')

    bmesh.update_edit_mesh(mesh)

I believe the specification is that the result of using bpy.ops.mesh.bisect will select the cut surface of the mesh. Therefore, if you want to bisect an object, you can copy the object beforehand. The destination object is the opposite of the bisect method.

If you interact with a bmesh via python script you have to call update_edit_mesh before you do any regular bpy.ops operations. Also you might need to experiment with running bm.select_flush/select_flush_mode to make sure that your programmatic selection updates correctly.


text:
How to get updated mesh locations after object collisions?
I am very new to blender. I have a scene like this,

The top plane is a cloth, the two cylinders and rectangle are collision objects. I click play on the timeline and get this after a few seconds,

I have this code that generates a point cloud for each center of a face on a mesh. This is the code.
import bpy

def point_cloud(ob_name, coords):
    """Create point cloud object based on given coordinates and name."""
    me = bpy.data.meshes.new(ob_name + "Mesh")
    ob = bpy.data.objects.new(ob_name, me)
    me.from_pydata(coords, [], [])
    ob.show_name = True
    me.update()
    return ob

def face_centers(obj):
    """Returns median center coordinates for each face of given mesh object."""
    if obj.type == 'MESH':
        import bmesh
        bm = bmesh.new()
        bm.from_mesh(obj.data)
        return [obj.matrix_world @ f.calc_center_median() for f in bm.faces]
    else:
        return [(0.0, 0.0, 0.0)]

ob = bpy.context.active_object
pc = point_cloud(ob.name + "-pointcloud", face_centers(ob))

# Link object to the active collection
bpy.context.collection.objects.link(pc)

My problem is when I run it, the mesh locations are not updated after the simulation.

You can see the locations of the point cloud is in the original location of the cloth and not in the new updated location after the collisions. How can I get the new updated mesh face coordinates after the simulation has played? The code works as intended its just the mesh face locations are not correct and "outdated".

just try this:
if obj.type == 'MESH':
    import bmesh
    bm = bmesh.new()
    d = bpy.context.evaluated_depsgraph_get()
    bm.from_object(obj, d)

instead of:
if obj.type == 'MESH':
    import bmesh
    bm = bmesh.new()
    bm.from_mesh(obj.data)

good luck!


text:
Blender hanging when using threading cond.wait() in python
I have this code that iterates over a lot of .obj files, applies some properties, plays the animation, then write some information about it to a file
for filename in glob.iglob(source_dir+'\**', recursive=True):
    if os.path.isfile(filename) and filename.endswith(".obj"): # filter dirs

        # Import the next clothing mesh
        imported_object = bpy.ops.wm.obj_import(filepath=filename)
        new_mesh = bpy.context.selected_objects[0]

        ... # Apply cloth, translate it, resize it...

        # Clear last handler (Used if script is ran multiple times)
        bpy.app.handlers.frame_change_post.clear()

        # Multithread lock
        condition = threading.Condition()
        callback_done = False

        # Define callback
        def stop_playback(scene):
            #nonlocal callback_done
            if scene.frame_current == 60:

                ... # Get mesh data

                # Stop simulation
                bpy.ops.screen.animation_cancel()

                # Write data cloud data to file
                with open(output_file, "w") as f:
                    f.write(data)

                print(f"Wrote {file_name} data to : {output_file}\n")

                # Release lock
                with condition:
                    callback_done = True
                    condition.notify()

        bpy.app.handlers.frame_change_post.append(stop_playback)
        bpy.ops.screen.animation_play()

        # Wait for callback to finish then perform next iteration
        with condition:
            while not callback_done:
                condition.wait()
            callback_done = False

I have the handler "stop_playback" which I need to run after the simulation/animation is finished so it can finish writing to the file. But I can not start the next iteration of the loop until the callback has finished writing to the file because then variables get all mixed up and bad things happen. I tried to use condition variables so the main loop thread waits until the stop_playback thread has set callback_done = True thereby continuing to the next iteration. Thing is, this code just causes blender to hang and white screen me. I am really not sure what is wrong or how to work around this.
If requested I can share the entire code, I cleaned it up and removed unnecessary things for this post. If your curious I need to batch process thousands of .obj files after applying a cloth sim to them. I will end up doing this in headless mode but want to get it working here first.

It will never reach condition.notify inside the frame_change_post handler because to the handler to be called Blender should finish and exit your script and progress its modal execution but it is stuck at condition.wait inside your script.
Consider this example. It will not start printing frames until it waits for 5 seconds.
import bpy
import threading
import time

def print_frame(scene):
    print(scene.frame_current)

bpy.app.handlers.frame_change_post.append(print_frame)
bpy.ops.screen.animation_play()

time.sleep(5)


text:
Dark faces in edit mode
so as you can see in the pictures some faces are abit darker or idk what to call them
i've tried recalculate normals but didn't help, same thing with merge by distance, blend file enter link description here

That's a normal smoothing issue. If you set the default cube to smooth shading, it looks weird as well. That is because the interpolation of the face normals tries to cover 180 degrees over one edge. Starting at -90 on the left the true normals are 0 and to +90 on the other side (relative to the global up axis). That's simply not enough geometry to do that kind of interpolation.
3 solutions:

More geometry, e.g. using a SubSurf modifier (easy, but heavy on the
    polycount)
Manually add edge loops, not a good idea for your
    specific model.
Using edge split.

The cube by default is set to flat shading which splits every edge, so each face has its own normals, no interpolation. Nothing looks too dark, but everything is choppy. Edge Split (for example done by a modifier) lets you decide at what angle there will be a split between two faces, to stop interpolation between them.


text:
Weird colors in normals map
so everytime i try to bake normals i get these weired colors

Things worth mentioning

im using blender (blender cycles)
ray distance = .1

Blend file
https://drive.google.com/file/d/1h5ofCYo1R8Fzeo7yEXAsSBvmBSD0_Aqz/view?usp=sharing

Welcome to the site :) For future reference we prefer .blends to be uploaded here

If you increase the bake Ray Distance to, for example, a value of 3, it works. It looks like it's because your objects are big on the scene, if I decrease them and apply scale it will need a lower value.

Thank you, i've tried but still doesn't seems to work(same problem)

it's weird because if I open your file and just change the Ray Distance, it works fine. By the way, you're not in Blender Internal, you are in Cycles.


text:
what is mean black & white texture
I download .obj modeling file on the internet
I open the 'texture' file there is a lot of black and white image.
I think black is mean that a part of a model.
Can I select only the black part of UV map or model?
I want to put on a material to the black part.
Thanks!

Add some pictures it will be easy to help.

The map could be a roughness map, metallic, Transmission, and so.
GrayScales give you a value for drive a single parameter.
Can you post images?

https://imgur.com/a/3jQejmu

yes! it's a value channel.
This map could be controlling values like roughness, metallic, transparency, SSS.
The map can't be Diffuse, because is using values like zero and one.

How can I use value channel? Should use node? Can you show me an example? Really thanks

Please post model printScreens and the "demo" result.


text:
Gradient background idea
I just curious that how can I make this gradient background?
I use gradient image texture but It didn't look like this.
Should I use light set ups?
Thanks.

I guess there are many ways to do it but here is one:

Create a plane that you bend on the background. Give it a Subdivision Surface modifier and a Smooth Shading.
Create a Spot and play with its parameters (mainly Lamp Size, Spot Shape Size and Strength).
To give no influence to the World, disable all its Ray Visibility options .

Maybe just flood the cove a bit so your answer shows a gradient in the background? .. If I haven't misunderstood the OP..

you're right, I've edited, I think it's better


text:
Assign more than 2 shape keys to same object bone
Initially I had 2 shape keys for my eyebrows which I used as a driver using a bone z location (-3*var and 3*var). This worked fine. But now I wanted to create a third shape key. So after that I added this key to the same driver bone using expression 6* var. But this does not work. Seems like only 2 shape keys work at a time using this setup. Can anyone explain it to me why so?
Thanks!

I think I could help if I knew more details. Could you link your .blend file?

Are you putting th driver on the shapeKey's influence? Also, what is the variable? Some variables don't play nice with drivers in the old (2.79) depsgraph (I think this is fixed in 2.8).


text:
Better to add extra bones before or after generate rig
Im using rigify addon and plan to add some shape keys and some drivers later on like for facial expressions and talking. Is it a good idea to add those driver bones to the metarig before I click generate rig or should I generate the rig and then later on edit the new rig by adding more bones?


text:
video sequence editor seconds milliseconds
Is there a way to see the units in seconds+ milliseconds rather than seconds + frame in video sequence editor? I am trying to sync dialogues from a track in audacity and every time I have to do the math of converting seconds to frames.

Why not let Audacity display the frames to match those in Blender? You can adjust the view down there in Audacity...

yeah, that's what I ended up doing. Thanks!


text:
Baking rigid body physics - Blender 3.0
This is probably a basic question but I can't find an answer that is relevant to Blender 3.0
I baked an animation with rigid body physics and particle physics for 300 frames.
I now want to extend the animation to 400 frames. The particle simulation keeps going but the rigid body simulation still stops at 300.
How do I re-bake the rigid body physics again so that the action keeps going for 400 frames? Blender 3.0 doesn't seem to have a 'bake' button anymore.
Thanks

For the rigid bodies you need to bake or delete the bake in the Scene panel > Rigid Body World > Cache

@moonboots Thank you so much!

For the rigid bodies you need to bake or delete the bake in the Scene panel > Rigid Body World


text:
Objects are automatically attaching themselves to rigify rig
My rigify rig has dotted lines to the world origin as if there are object constraints, however I haven't added any contraints. I am unable to add new objects in to my scene without them automatically attaching to my rig - if I add a cube and try to move it, the rig moves with it too. Does anyone have a clue as to why this is happening?

If it's a rigify rig, those are to the rig's root bone.  Select the rig, go to pose mode, open the sidepanel (shortcut 'N') and see if "Root" is selected.  It's probably not, so the boen doesn't show up.

@MartyFouts Thanks for commenting. I couldn't find an option anywhere for 'root'. I ended up deleting the rigify and using the armature to pose instead.


text:
Is there any way to change viewport preview pass through script?
I have mastering blender, but i'm absolutely beginner in python or blender script.
i just can use the script trough copy from the "Info" area then paste to "Text Editor"
then Run it.
but i get confused to change preview passes trough script
the line from the "Info" (when i switch the passes) is
bpy.data.screens["Scripting"].(null) = 'NORMAL'

i copy and paste to the editor, so like this
import bpy
bpy.data.screens["Scripting"].(null) = 'NORMAL'

and the script won't run, its get invalid syntax
any help will be appreciated
thank you

Developer Extras
Relying on the info area to write scripts is IMO not the way to go.
Some posts explaining how to find what the property is.
Changing the shading type in Python
Blender python : How to set object appearance in viewport?
With developer extras turned on mousing over the property

Telling us the type and its property of interest View3DShading.render_pass  For a 3D viewport, will find any property setting belongs to the space.   Scrolling to References at bottom of page confirms this ie SpaceView3D.shading is an instance of View3DShading
To the python console:
>>> for i, a in enumerate(C.screen.areas):
...     i, a.type
...
(0, 'PROPERTIES')
(1, 'CONSOLE')
(2, 'VIEW_3D')
(3, 'TEXT_EDITOR')

Area 2 is a view 3d, its active space
>>> space = C.screen.areas[2].spaces.active

The render pass property of shading group
>>> space.shading.render_pass
'COMBINED'

Set to something else.
>>> space.shading.render_pass = 'MIST'
>>>

Note in a script to run from the context of a view3d, then use
space = context.space_data

thanks a lot for the answer, and i've try it.
but sadly its only work in "Material Preview" not in cycles render preview as well
https://blender.stackexchange.com/questions/187390/why-this-simple-script-only-work-in-material-preview-not-in-cycles-render-pre


text:
Switch Direction curve splines without bpy.ops?
Is it possible to switch direction curve without calling bpy.ops.curve.switch_direction() ?
its would be nice if there a way to switch direction from the data curve without selecting point in edit mode.


text:
Intended way to change object color outline during modal?
Let's say, when you moving the object (by pressing G)  the outline color would change to white during operation.

Since I don't know how to achieve that, so i tried to implement that by changing the theme color temporarily during modal operation and restoring back the color on Confirm or Cancel the operation.
its work as expected indeed, however if an unexpected error happens during modal, the color changed will still remain unless changed back manually (or reset) through Preferences.
so I'm wondering if there is any intended (or the best) way to change outline color during modal operation?
import bpy
from bpy.props import IntProperty, FloatProperty, FloatVectorProperty

class ModalOperator(bpy.types.Operator):
    """Move an object with the mouse, example"""
    bl_idname = "object.modal_operator"
    bl_label = "Simple Modal Operator"

    first_mouse_x: IntProperty()
    first_value: FloatProperty()

    color: FloatVectorProperty()

    def modal(self, context, event):
        C= bpy.context

        if event.type == 'MOUSEMOVE':
            delta = self.first_mouse_x - event.mouse_x
            context.object.location.x = self.first_value + delta * 0.01

        elif event.type == 'LEFTMOUSE':
            C.preferences.themes[0].view_3d.object_active= self.color
            return {'FINISHED'}

        elif event.type in {'RIGHTMOUSE', 'ESC'}:
            C.preferences.themes[0].view_3d.object_active= self.color
            context.object.location.x = self.first_value
            return {'CANCELLED'}

        return {'RUNNING_MODAL'}

    def invoke(self, context, event):
        C= bpy.context
        self.color= C.preferences.themes[0].view_3d.object_active
        C.preferences.themes[0].view_3d.object_active= (1,0,0)

        if context.object:
            self.first_mouse_x = event.mouse_x
            self.first_value = context.object.location.x

            context.window_manager.modal_handler_add(self)
            return {'RUNNING_MODAL'}
        else:
            self.report({'WARNING'}, "No active object, could not finish")
            return {'CANCELLED'}

def menu_func(self, context):
    self.layout.operator(ModalOperator.bl_idname, text=ModalOperator.bl_label)

# Register and add to the "view" menu (required to also use F3 search "Simple Modal Operator" for quick access).
def register():
    bpy.utils.register_class(ModalOperator)
    bpy.types.VIEW3D_MT_object.append(menu_func)

def unregister():
    bpy.utils.unregister_class(ModalOperator)
    bpy.types.VIEW3D_MT_object.remove(menu_func)

if __name__ == "__main__":
    register()

    # test call
    bpy.ops.object.modal_operator('INVOKE_DEFAULT')

I believe changing it in the theme is the only way to do that. Obviously if your code crashes the code that changes it back will never get run. The only way around that would be to catch the exemptions with a try: except:


text:
Screen space refraction option seems to be in Blender 4.1.1
The screen space refraction option is missing in the material settings tab.
Am I missing somthing or is there a way to get the same result another way?
In the Blender doc it says it is still supposed to be there.

It's an option in Eevee, not Cycles

Not sure what the title is supposed to mean.

Screen Space Refraction is an option available in Eevee, not Cycles, you are probably in Cycles


text:
How to print material names (two materials) for selected object
Main Problem
I work on some specific script which generated list - creates new CSV file and I try to attach information about name materials so name would fit to name of object.
I am pretty new in scripting so please help me understand that. I have found many similar topics, but I just can't use it as I need; (like material index name or number, or object data, or active material) :/
I try find that in internet, but I can't find like this. Closest to my need is:
context = bpy.context

mesh_objs = [ob for ob in context.selected_objects if ob.type == 'MESH']

for mesh in mesh_objs:

    print("active_slot:", mesh.active_material)

And that generates this:
active_slot: <bpy_struct, Material("MaterialOne") at 0x000001EB95BE5008>
active_slot: <bpy_struct, Material("MaterialOne") at 0x000001EB95BE4A08>
active_slot: <bpy_struct, Material("MaterialOne") at 0x000001EB95BE5008>
active_slot: <bpy_struct, Material("MaterialTwo") at 0x000001EB95BE5008>
active_slot: <bpy_struct, Material("MaterialOne") at 0x000001EB95BE5008>
active_slot: <bpy_struct, Material("MaterialTwo") at 0x000001EB95BE5008>

But I need something like this (it can look different, this is no problem), for example:

of course only selected Objects
situation when you have more then 2 materials on slot 1, and on slot 2 is basically one or none

MaterialsList
Cube.001, MaterialOne and DiffrentMaterialOne
Cube.002, MaterialTwo and None
Cube.003, MaterialOne and None
Cube.004, MaterialTwo and None
Cube.005, MaterialOne and DiffrentMaterialOne
Cube.006, MaterialTwo and DiffrentMaterialOne

Let me know if it is possible.

Hello ! You can't have more than one material per slot, could you elaborate on what you are trying to do ? (the end goal and the input objects)

StackExchange rules require one question per question, so you should probably make additional questions for your second and third questions. Have them point back to this one for details.

Hello and welcome. Please don't ask more than one question per post. Use the [edit] below, to break this into multiple posts so that each focuses on a single issue. Make as many separate questions as necessary.

If you are serious about learning how to script, I strongly suggest you watch the video tutorial series Scripting for Artists from Blender Studio.
I will answer your first question, but as has been pointed out in the comments, you need to split the other two questions into separate posts.
Your original Python fragment is very close to what you need.  But you need to append .name to mesh.active_material to print the name instead of the Python representation of the object:
import bpy

mesh_objs = [ob for ob in bpy.context.selected_objects if ob.type == 'MESH']

for mesh in mesh_objs:
    print("active_slot:", mesh.active_material.name)

But since you want all of the materials associated with the object, there's a simple way to do so.  mesh.material_slots is a list of all of the material slots assigned to a material.  So you can use a simple loop to print them all:
for mesh in mesh_objs:
    for slot in mesh.material_slots:
        print(slot.name)

But that prints the slots on separate lines, and it prints a blank line if the object has an empty slot.
If you don't want the print to add a newline, python has an optional argument to print, that says what to end the print with instead of the new line.
So here's some code that uses that option, and by the way includes the name of the mesh object in the output:
for mesh in mesh_objs:
    print(mesh.name, end = ", ")
    for slot in mesh.material_slots:
        print(slot.name, end = ", ")
    print()

Notice the additional print statement in the for loop?  That's because the previous print statements had not terminated the line.
This code doesn't print exactly what you want.  It has (at least) four problems:

It uses ", " rather than "and " between the materials
It adds an extra ", "
It doesn't print "None" if the material slot is empty
It doesn't stop at the 2nd material.  It will print every material associated with your object.

There may be others, but they may be problems you won't care about or encounter.
Now I would argue that the last problem isn't a problem.  You seem to be limiting things that don't need to be limited.
I leave you the first two problems as exercises.  The first one is trivial, and having seen how end = works in print you should have no problem with it.  The third problem is solved with an if statement that prints something different if the slot is empty.  That should be easy to figure out.
The last one also requires changing the logic of the code.  There are many ways to fix it, but I leave it to you to pick one.
Finally, there's an issue with the way you've described the problem.  As mentioned in the comments on your question, a material slot can only have one material in it.  I assumed that that was an error in the description and wrote the code and explanation using that assumption.
As I mentioned earlier, I will only answer the first question here.  Please ask additional questions for the 2nd and 3rd points.


text:
How do I move certain vertices to another mesh?
In blender - I have a mesh finished, but I need to add a moving object, but I already made a mesh, and I need a hole EXACTLY the size too, so I need to get the vertices where I want the moving part to be, and turn it into it's own mesh that I can animate, kind of like adding a new object with the Add menu.
Edit: this was solved by Allen Simpson, Apparently I just have to press  P.

Hello, what you mean exactly by turning some vertices into their own mesh?

@moonboots I updated the original post, it should be more clear now.

Do you mean duplicating the vertices and Separate By (P) -> Selection?

@Allen Simpson Yes!! Exactly! Thanks a lot!!

I'll try to find a duplicate to link this to, I think your title is good for search results.

https://blender.stackexchange.com/questions/6184/splitting-pieces-of-a-mesh-into-a-new-object?noredirect=1&lq=1

@DiamondUp Welcome to the site, this question was closed due to a lack of detail.  This isn't "bad" or a punishment or anything, in this case it's just been linked to a canonical answer.  Feel free to ask more questions, we're glad to have you here. https://blender.stackexchange.com/tour


text:
There's something wrong with my topology, but I'm not sure what
I am working on chair design for my portfolio. And there's like this tearing or jagged edge where the side of my mesh meets the top. Any assistance/ advice would be appreciated.
This is the image in edit mode. Note the front area, that's curving

In this image it's in object mode. The area looks kinda sharp, but it's only in this small area

hello, please share your object so that we can check (upload and copy paste the URL it will generate): https://pasteall.org/blend/

Thanks for the grammatical edits, and for reaching out. Below is the URL to the modelhttps://pasteall.org/blend/56ca9f49736e433aa3ef56b7792ede26

Try recalculating normals (SHIFT N) and also merge by distance. If it didn't solve it, inspect your mesh in x-ray mode to see if there's extra faces inside the mesh.


text:
Glass looking wierd in rendered result

That's the glass in the  rendered viewport shading. But when i render it, its coming out totally wierd.

How do i go about this please

There is indeed some weirdness going on here - however it looks like the geometry might be different. As suggested, try to go through your modifier tree and see if anything there is odd. Alternatively could you provide a link to the file?

it looks like there is a solidify modifier in the preview but not in the render

You most likely have modifiers that are not visible in render mode, changing the way it will look. Make sure that every modifier is enabled for rendering.

Thanks so much guys. I had the use modifier during render button turned off. Turned that on and the glass came out well.

Please don't use answers to write comments. In future put this in the comment section under your question.


text:
How do a make a material continuous on separate objects?
I am trying to make a puzzle of about 20 individual(seperate) pieces and have a material I made for it be applied across it in a continuous manner. I need the pieces to be an object of their own so that I can move each one independently. However, when I apply the material individually, each piece has the exact same appearance instead of each a part of the appearance I want. I hope I'm making sense. Here is an image as an example of what I mean. The 9 blocks on the left collectively give me the desired continuous appearance. The 9 on the right don't. Each one is a copy of the same pattern. The only way I have been able to have get it to be continuous is by joining the 9 blocks but that won't allow me to move each piece idependently. Any ideas?

did u try to use object as input for texture coordinate?

@Chris Dude thank you so much. That was it. Problem solved.

If you plan on using UV coordinates, you can select multiple objects at once and unwrap them all in the same operation.


text:
How to make a table with 2 materials for the top?
I'm trying to make a round table and I'm still really new to blender.
The table is supposed to use 2 materials for the top, wood for the edges and glass in the middle.
I tried to use the boolean modifier with 2 cylinders and after that didn't work I tried it with filled in circles, which also didn't work.
I hope you can help, thanks in advance!

Some images of the mesh and an image of what you're trying to achieve would help! https://meta.stackexchange.com/questions/75491/how-to-upload-an-image-to-a-post.

select both faces of the table in face select mode, and press I to inset

edge -> bridge edge loops

extrude individual faces -> S -> 0

select all inner faces (also on the bottom side)

add new material -> glass -> assign

invert selection

add new material -> wood -> assign (e.g. you could get a free wood texture from free blenderkit add-on)

you might get this:

so go back in edit mode again, in face select mode box select the "rest":

select your glass material:

and hit assign

This works for cycles.
In Eevee you have to use alpha blend as blend mode in the glass material:

I appreciate you constructing an inner face in this situation :p

yes, else the glass would break - as every construction worker knows ;) i am just totally disappointed of Blender SE that until now nobody wrote that i cannot use this geometry because it is totally shit... ;) i mean, just hitting F to build a gigantic n-gon - that was just tooooo easy ;)


text:
Looking to explode wood block in 2.8
I am looking to explode a wood block and reveal a text logo in blender 2.8. My original idea was to make cube with a remesh modifer and apply with a quick explode. The problem was that no matter what I did there was a bug in the code that wouldn't apply the explosion correctly.
My second attempt was to make a cube ND Subdivide it with loop cuts it accepted the quick explode but the result was not a real explosion, the particles just pealed off of the cube but would not lay down in a pile or without a collision set up they would not all fall through the floor correctly. Either way I was looking to explode the  cube not to have it just fall to pieces.
Idea?s

You may have a look at Cell Fracturing, either the standard in-build one or the standalone add-on version. There are many great tutorials for it on YouTube, too.
Maybe you can adapt this tutorial from CGGeek? You only need to add a ground (rigid body, passive type), play with the shard settings (wood usually has a high number of long splinters) and maybe use an object to push the wood from behind instead of below. Also, no smoke sim needed, obviously.
https://www.youtube.com/watch?v=J70DijACZm0
Another (older) tutorial, could serve as a reference for settings:
https://www.youtube.com/watch?v=w_m81zF9WtY


text:
uv map not visible in object mode
Here's what I hope is a simple question.
I have a mesh with a wood texture map and a bevel modifier. The woodblock displayed correctly using the cycles render engine.
The trouble came when I added a remesh modifier then the block displyed correctly in edit mode but not in object mode or when I rendered it.
Please disregard the bad placement of the map  enter image description here

Can you post a .blend file to look at?

Remesh modifier changes the topology of the original mesh. This change can be significant or insignificant depending on the settings you chose. If the UV map looks mangled after using this modifier, then you either have to change the settings to better fit the original mesh or redo the UV map after applying the modifier so it fits better.

I'm not sure how to post the blender file. I forgot to mention I'm using 2.8

I went back and tried to add the uv map again but it didn't work.

I also wanted to add a shot of the object in the object mode but it didn't allow me to post 2 pictures. The object mode and rendered image shows the block as hust solid brown without the grain


text:
Running blender from the command line
My blender will not run and it's been suggested that I run blender from the command line with a factory reset option however I am not familiar with how to do that.
What is the actual command after c:> ?

I'll be describing two approaches, one for the case that you don't know where the blender.exe is located, there other for when you do.
In case you don't know Blender's install directory:

Open the Windows Explorer WIN+E
Navigate to C:\Program Files\Blender Foundation\Blender and verify that the blender.exe is present. If it is continue with step 4, otherwise step 3.
In case you didn't find the blender.exe go back to C:\Program Files and use the search box to search for blender.exe. When it's found right click on the item and select Open File Location.
Click in the address bar that displays the current path and replace the text with cmd. Press enter and a command prompt should open with the working directory set to the path where Blender is located.

If you already know Blender's install directory:

Open a command line WIN+R and type cmd and press enter
If Blender is on a drive that isn't C: you will have to change to the correct drive. You can do this by typing the drive letter and pressing enter. For example if Blender is located in K:\05_Download\blender-2.80-windows64, you would type K: and press enter.
Change the directory to where Blender is located. Use cd to change the directory, for example cd K:\05_Download\blender-2.80-windows64.

Now you can start Blender with the (temporary) factory settings. Once you close and restart Blender without the flag it will load your preferences. This is better than doing a factory reset, when you only need to temporarily disable preference loading.
.\blender.exe --factory-startup

Another flag that is useful in case Blender crashes is --debug which will display debug information on the command line.
.\blender.exe --debug

The full list of command line arguments can be found in the manual.

Running Blender from the command line is unlikely to make any difference. If Blender does not run correctly, check that your Graphics card supports OpenGL version 3.3 and other minimal hardware requirements and that your graphics drivers are up to date. Also try re-downloading Blender and re-installing it. Also try the zipped version.
You do not need to run Blender to reset user preferences(factory reset), you can delete(maybe backup first) the user preferences files that are on %appdata%\Blender Foundation\Blender\[version number].

I tried and ran blender from the run/command box and it ran correctly but did not save the settings when I closed and re-ran the program.


text:
reset preferences file
When I run blender from the run/command box, in windows 10, the program launches and runs correctly however when I close and reopen the program the original bug is still there.
I am trying to reset the preferences file to clear a bad reference. How, where and what is the name of that file.

Did you try to reset the preferences in Blender? Edit > Preferences to open the preferences, then click on the button in the bottom left corner Load Factory Preferences and then Save Preferences.

Yah! It finally worked it was so easy yet no one suggested it.


text:
Error which halts program
This is an error message which stops the program. I did a complete delete and reinstall and the problem followed.
This is a windows 10, 2.8,  running on a Lenovo yoga 730 with 8 meg ram.
I also tried installling 2.81
Report error
Traceback (most recent call list)
File “C:\blender\blender2.80\2.80\scrips\bl_operators\wm.py”,line525,in execute value =                 context_path_validate(context, data_path)
File “C:\blender\blender2.80\2.80\scrips\bl_operators\wm.py”,line85,in execute value =                 context_path_validate.%s” % data_path(context, data_path) if data_path else Ellipsis
    File “,line1,
    AttributeError: SpaceError’
   Location :-1

try running from the command line with blender.exe --factory-startup to stop it loading any existing config files.

I am not familiar with running programs from the command line. What is the actual input after c:> ?

I tried and ran blender from the run/command box and it ran correctly but did not save the settings when I closed and re-ran the program. I'm not quite sure how to find and delete the preferences file you are referring to. Can you be a little clearer what the name of the file is and where to find it?

once you have blender running you can go into preferences and the little hamburger menu has the option to save preferences.


text:
How would I wrap a texture around a cylinder without it looking off?
Im making a chrome exhaust muffler for a racing game but when I try to texture it, i get this ugly line going down the center and when I look at the uv map it seems that one side of the texture is jumping to the other side of the surface, if that makes sense so it looks very off. How would I fix this?

This is because your texture is not "seamless" mainly due to the reflective shine in the middle:

You need a seamless texture and then bake the shine on it if you need it on the texture.
Something like these: https://naldzgraphics.net/free-seamless-metal-textures/
But since you said it was for a game, you'd have to make sure the textures are allowed for use in games and not just personal use.
Alternatively, you could look into "Procedurally Generated Textures" there are lots of tutorials on it. This is a great way to generate seamless textures without the worry of copyright.


text:
Meshes not showing up correctly in Blender when opening a blender file
I seem to be running into some trouble while using Blender. Whenever I try to open a blender file in my latest version of Blender, none of the meshes in the said file show up. I can see thin lines in wireframe view, I can't see any meshes in solid or material views, and I can see a transparent version of the meshes themselves in rendered view. Maybe there's a bug with this program. But regardless, I need some help finding a solution to this problem I'm currently having.

Hello and welcome. can you attach your blend file. https://blend-exchange.com

An image of the effect you're seeing would help but it sounds like a graphics driver problem. Have you updated the graphics card drivers recently?

I might have found a solution myself. All I had to do was disable GPU Subdivisions.


text:
Recreating Microbots Scene
I'm trying to imitate this scene from big hero where he uses a lot of microbots to form a bigger shape.

I think I'll have to use a particle system with the microbots as an object and have a model of the thing I want the microbots to take the shape of but I can't get any further than that. Can someone tell me how it's done?
Thanks

My answer here might help you... https://blender.stackexchange.com/questions/274508/what-is-the-best-way-to-naturally-animate-hundreds-objects/274527?noredirect=1#comment471233_274527

It did, thank you


text:
UV wrap Eye Img on sphere
I have this img and I want to correctly texture a sphere with it. I have minimal no knowledge of UV unwrapping. I want to apply it to either half the sphere or to both halves. I tried making a seam to split it in half then unwrap it but I either did it wrong or it didn't work.

Help : )

If you want to use UV mapping but have no idea how it actually works, I would strongly recommend watching a few tutorials on this topic, since this site is not for giving tutorials but rather answering specific questions. So, for example, if you would tell us how you tried to unwrap your model or show a screenshot of what the resulting UV map looks like...

I did it. I mirorred it then made a seam in the middle and tweaked it on the img and it worked


text:
Make particles interact with a flip-fluids simulation
I want to make a particles from the particle system to interact and create ripples on the fluid simulation. Again I'm using flip fluids. I tried setting the emitter as an obstacle and tried to set the object(of the particles) to an obstacle too but I had no luck with both.
Need help ( :

This is a bit odd. I believe mantaflow doesn't support using particles as effectors for collision, only for smoke inflow. Are you familiar with the new simulation branch for geometry nodes? You could potentially make your own basic particle system, realize the instances at the end, and use it as an effector in the liquid sim. I haven't tried it, but it should work. Mantaflow does support animated meshes, as collision objects.
A superior fluid system is the FLIP FLUIDS Addon. It's not free, but it is open source, so if you're willing to compile it yourself, you can get it for free. It might support particles, but I'm not certain.
Keep in mind, if you've got a static mesh or fluid surface and you want to create small ripples, you'd use Dynamic Paint. However, it loses the ripple movement when the underlying mesh changes, especially the vertex count.
It's kinda disappointing that Blender's fluid system is still somewhat limited, but iam hoping the upcoming simulation nodes will bring some improvements.

Well said, that's what I did btw used dynamic paint and it was actually more preformance friendly.


text:
Export rigid body simulation as fbx
I made a Rigid body sim and baked it now I want to export it as fbx. I didn't want to place a camera and have it as a vid. I wanted to be able to view it as 3d but whenever I export it the animation is just not appearing. I set path to copy and unchecked nla strips.

AFAIK, doesn't really support deformations outside of bones and shapekeys. Use Alembic instead.

I'll try that but I hope someone finds a walk around

You can't really force a format to export a data it can't support x) Meanwhile Alembic is designed to export such things.

Your right, Can you tell me how to view alembic files. the default 3d viewer for widows doesn't open it

Use Blender or any real production tool. Windows' 3d viewer is barely a playtoy.

I think the only software that exports RBD data as FBX is Houdini. It transfers the simulation data to shapekeys animation


text:
Fluid Disappearing
i have a rigid body sphere rolling down a ramp and it is an inverse obstacle containing water(flip fluids)
as it rolls down the water disappears gradually
Video of bug
can someone help me please
thanks in advance

I do not own FLIP Fluids, but the main leak seems to happen as the fluid pushes up against the pole of the UV sphere, which has a lot of edges connecting to one vertex. I suspect the high edge connection count may be a weak point in the fluid collision detection, so I recommend you use an icosphere instead as it has uniform connecting edges. You may also have to turn up quality steps or other precision settings on the fluid simulation as well, though. As a general rule of thumb, more force means more simulation errors and instability, and the more precision needed.

Thanks for your help but, i attempted it with an ico sphere yet the issue presisted

You did rebake the cache and try adjusting the other settings, yes?

i rebaked with the same settings


text:
Break stuff *without* cellfracture
I'm making a scene where a bullet is shot at a glass object fracturing it completely. cell fracture is great and usually works but it has 2 major flaws. the first is that it sometimes misses fragments in the mesh and you end up with a large gap in your fractured mesh. and the other is that the object appears to be cracked even before impact. The 2nd problem can be easily avoided by keyframing the appearance of shards and the disappearance of intact mesh and it usually passes unnoticed in a quick-paced collision but my scene is slow motion with a high frame rate and I'm trying to make it as realistic as possible so it's not really an option.
If ur lazy read from here:
Is there an addon or a workflow or even a geo node tree that enables me to break objects (glass mainly) realistically where the fragments separate and break gradually and only when collided with?


text:
Does scaling a mesh/curve object to 0 remove its render impact?

I'm currently using the latest build of Blender 2.8 as of this post's timestamp, and I noticed I can't keyframe the viewport visibility parameter (see above) in the Outliner like in 2.79. The render visibility parameter (already yellow/keyframed) works fine.

This error is probably because the feature is not implemented yet, but this whole situation has made me look into other methods of hiding and unhiding objects in my animation. Specifically, I want to know if scaling a mesh or curve object to 0 will remove that object's impact on render time, as if it was never in the scene.
It makes the most sense to just use 2.79 until this new Blender version is finished, but I vaguely recall overhearing once that keyframing this parameter with a large number of objects at a time is not recommended, so it's a good opportunity to explore alternatives.
So does scaling to 0 remove an objects impact on render time? If not, what are some other ways I can animate object visibility (excluding keyframing a material's transparency)?

Yes, if the object is 0, it does remove the object from render time.
Good Luck

Honestly, I should have tested this before making the post lol. Thank you! I checked with an old file of mine, and rendering objects scaled to 0 does, in fact, take as much time as deleting them from the scene altogether.


text:
Blender 2.8 - Get Environment Texture Path from UI to python script
i'm unable to get inside a python script the path of th Environment texture that i assign in World->Color from the Blender UI.
I want to set the .hdr there and than get from there the path (C:/.../123.hdr) for other uses, but i need it inside a script.
Thanks for help!

Finding things with the python console.
The scene has a world.  context.scene.world. When nodes are being used the object will have a node tree. world.node_tree The tree has nodes. Consult the manual or the many questions / answers re nodes for more info.
Note: The properties space has a world member of context context.world other spaces may not
Here is a simple example using the python console.  C is a convenience variable C = bpy.context
>>> C.scene.world
bpy.data.worlds['World']

>>> C.scene.world.node_tree
bpy.data.node_groups['Shader Nodetree']

Here I've used autocomplete CtrlSpace to expand available options
>>> C.scene.world.node_tree.nodes['
                                   Background']
                                   Environment Texture']
                                   World Output']
>>> C.scene.world.node_tree.nodes['Environment Texture'].image
bpy.data.images['Untitled']

See that the environment node has an associated image.  Since I've simply added a blank untitled image it has no filepath.  A loaded image will.
>>> env_img = C.scene.world.node_tree.nodes['Environment Texture'].image
>>> env_img.file
                _format
                path
                path_from_user(
                path_raw
>>> env_img.filepath
''

Adding an environment node, given you have a path to the image path
>>> world = C.scene.world
>>> world.use_nodes = True
>>> enode = C.scene.world.node_tree.nodes.new("ShaderNodeTexEnvironment")
>>> enode.image = bpy.data.images.load(path)

Related:
How to set a background using the cycles render engine with the API

The only thing that is missing is to then link the node: node_tree = C.scene.world.node_tree node_tree.links.new(enode.outputs['Color'], node_tree.nodes['Background'].inputs['Color'])


text:
Cut object into two objects with a plane
is there a way to cut an object into two objects with a plane without duplicate that object and extruding the plane in both direction applying a boolean operation?
My mesh is complicated because it is generated by a 3d scanning so the knife project isn't enought.
The knife project gives me the line where the two object should be separated, but i need to separate the objects manually along a very complicated mesh resulting in a waste of time.
Thanks!

https://blender.stackexchange.com/questions/5320/cutting-a-mesh-in-half https://blender.stackexchange.com/questions/50591/how-to-select-part-of-a-mesh-by-using-a-helper-plane

Xylvier, thank you very much for writing this add-on.
It is exactly what I need for a project I am working on.
With limited experience in mesh manipulation I need to show results to my employer, and your add-on is helping me get there, while creating time for me to learn to work properly with meshes from scratch.
Have a great day!

While i can suggest to use bisect, i have an even better solution, i wrote a little "free" add-on for exactly this situation. Called it Bisectplus, as it can take a plane object and generate 3 vertex groups which represent the cut loop, as well as both sides (which include the center each) to make it easy to use for further operations.
The source-code can be found under https://github.com/Xylvier/Bisectplus/
As it says, seeing is believing:

No harm was done to the monkey.

even if you cut objects with a plane, you will not able to see it, because plane has thickness of 0. you make create loop, and cut it with a V button


text:
How to add logo/decal while mix shader already full connected?
Hello my dear blender artists,
i know if we want to add some logo/decal on the model, we need to add image texture and connect it to the mix shader fac and turn the texture in stencil mode. but, what if the mix shader already full connected? how can i add the decal then?

you can add a new Mix Shader after the existing one

yeah i think about it too but, where should i connect the new mix shader then?

@ApasipepOyong: please click on "accept answer" so other users although know that the answer helped you. thanks.

Here is an example of what it can give if you want to add another decal. If you want an image to be displayed just plug the color output of the Image Texture into the color input of the Diffuse. You can also use another UV map if necessary (here, see the Input > UV Map before the new Image Texture).

aw.. thank you so much bro. you da man!


text:
How to make object on the conveyor snap to indexing rotary?
I tried to make an animation for bottle filling automation.
when the object smoothly can move on the spinning conveyor, it wont snap/stick to the indexing rotary which will be used as a grabber to place the object to each process (filling water, dropping bottle cap, screw down the bottle cap, and so on).

hello, could you please share your file? https://pasteall.org/blend/

ok sure. kindly please wait

here : https://pasteall.org/blend/891424f3017143bca8b3d67049565e10

seems complicated even if you correct some things like scale, origin position, etc, I hope a physics expert will find the right settings (if it's ever possible to do it correctly), but don't you want to simply fake it with some keyframes?

haha i knew it. using keyframe is always the last option.

i'm still thinking how to make the blue fence to become a wall so that object will eventually move straight to the red rotary thing and not fall down.

Maybe you can use a little bit of both, enable the physics until it reaches the snap point, then use keyframes to put it in place, and re-enable physics afterwards and use an invisible object to prevent it from going haywire

yeah bro, that's really cool.

but still, it is very obvious to see the bottle easily snaps to the rotary thing which seems not so realistic. it should be a little bit shaky movement that the bottle might aligns itself to the rotary.

I agree.  It was done in a hurry. I'll have a go at that...

wow dude! how you do that? it's really beautiful

I'll have to write it up and post up an answer with the Blend file.  Give us a day or two. Grass on the property is turning into a jungle here.

great! many thanks to you

Bottle conveyor belt -  (Blend file below)
EDIT 3/11/2021  (added 2nd movie clip)
This is a bit of a mouthful but I thought it best to describe in detail so it can be done step by step by those without experience.  The process itself didn't take all that long.
An alternative to swapping bottles could be to use the 'Child-of' constraint.  I personally find duplicate bottles easier in the long term and more straight forward.  Either way, you'd still need to Rotoscope.

All of this was animation without physics.  All keyframes are using linear interpolation.   You may have to go into the Dopesheet regularly to select ALL keyframes, then set them to 'Linear' with 'T'.
The details -
The leading bottle (bottle 1) is keyframed forward so it bumps into the rotary cam.  From there it was rotoscoped (see below) to emulate physics (bumps around) and enter the slot where it is visually switched with a duplicate bottle.
That duplicate is located in the rotary cam's slot permanently and parented to it.  It and it's siblings are all traveling around with the cam continuously as though on a merry-go-round, but not visible until needed.

At the switch-over frame, the 3D cursor is set to the duplicate's location with SH-S and the original then set to that EXACT position with SH-S again.  ( "Selected to 3D cursor" )
The original is switched (keyframed) to invisible in the Outliner and the duplicate switched to visible.  The change-over will be undetectable.
.
On exit the original bottle is again required to be be at the EXACT location of the duplicate where their visibilities are reversed.
Initially when Bottle 1 enters the slot and switches to invisible, it remains where it is.
The duplicate travels around with the cam, and at the exit frame, will be switched to invisible again.
Bottle 1 however will still be at it's previous location so it needs a keyframe at the exit switch-over frame to place it at the duplicate's precise location. (with SH-S)  That makes it casually stroll across to reach the duplicate where it will re-appear in the slot it entered, about to exit.
Once visible again Bottle 1 is rotoscoped a few frames to have it exit 'naturally' before one or more keyframes takes it down to the 2nd conveyor and out of sight.
Play the animation one frame at a time to see how it's done at the entry and exit.
Wobblies -
These are simply VERY slight rotations in X or Y axis every two frames.  At 25 fps, that's 12 every second which looks about right.  (try every 3 frames for 30 fps)
Once bottle 1 is wobbled this way, those keyframes can be exported to all the others in the Dopesheet.  Actually if each bottle is a duplicate of it's leading bottle, it would inherit those keyframes anyway.
Wobbling will be in synch like a chorus line so stagger some by sliding their imported keyframes one frame to the left or right.
A Note here. -
Whilst you might not want 'wobbly' rotation angles however slight when switching between bottles, you'd probably get away with it here because if there is a slight angular difference when switching over, that would probably be seen as just another wobble.  If it doesn't look right or 'jumps', re-keyframe Bottle 1's and the duplicate's Rotation to 0,0,0. at that frame.
Rotoscoping -
Is a term I use here to describe the adjustment of a bottle's movement, one frame at a time. (Manually keyframed frame by frame)
Subsequent bottles -
These are also animated to follow the others uniformly until either being bumped into a leading bottle or the rotating cam itself.  They can be rotoscoped manually as with Bottle 1 for a few frames to get it's entry looking right and matched to the duplicate's location.
(you'll notice that each duplicate bottle's location in the rotary cam slot is set to appear as though being pushed around by the slot's trailing circumference whilst being 'forced out' against the outer circular barrier)
.
4-Bottle Groups -
Once the first 4 bottles are done, further 4-bottle groups can be duplicates of the first.  They will inherit all keyframes and their behavior will be identical with the first group.  Timing along the first conveyor would need to be organised so the first of any group bumps into the cam at the same cam position as Bottle 1 in the 1st group.
With that achieved, entry behavior for each 4-bottle group should be the same as the others, requiring no further Rotoscoping unless appearing a little too linear.  If so, tweaking of individual bottles every so often is a simple matter of a little extra movement to one side or the other and keyframing that but not too much otherwise they'll be seen to 'jump'.
-===========-
Whatever action behavior is required, when the physics engine won't behave as you wish, animation allows you that freedom and without instabilty.  When unsure how to go about it, use the physics engine on a dummy object to give you the action it produces.  You then have a reference you can copy manually. (if it's usable)
.
Bottle Transparency -
The clip was rendered using OpenGL (direct from the viewport in vers 2.77) so the transparency may have to be re-organised in 2.8+ .
Conveyor Rollers -
These were a hurriedly done array and rendered as a pic.  That was used to texture the conveyor sections and their Diffuse keyframed to vary - cyclic fashion.  A much more effective solution would be to render a rotating array of rollers and use that for texture, or even place 3D rollers there direct.

wow! awesome dude! a big thank to you!!!

how can i follow you? do you have any account like youtube or tiktok that i can follow?

Hi again ,  I'm not on Social Media.  In between other things I take a look in here to learn and hopefully return the favour when I see a question where someone is asking for help. (and where vers 2.77 would still be relevant)
Following? - The only thing I can think of on this site is to click on a User's name and go into their profile.  All questions asked & answered are listed there.  Thanks for your comment BTW.  @Apasipep Oyong


text:
IK bone arrange for kid riding toy
Hello Blender artists,
i wonder what could be the right IK bone arrange for this toy mechanism?
the motion loop is more like this : https://www.youtube.com/watch?v=bhKRtBNinEM

Just use a simple arm IK rig. The "hand" (IK target) stays in place while the "shoulder" rotates in a circle.

The pole target is needed to prevent a "180° flip". Make sure the bone rolls are correct (check the bone axes), that the deform option is disabled for the helper bones and the bone hierarchy is correct so you can move the whole rig properly. The yellow bone has the IK constraint.


text:
Ocean Waves Simulation Setting
i wanna make an ocean wave simulation but i stuck with couple of experiments that has bad result as shown below. what is the best setting to make it looks really good?

Hi :). You can try the Ocean Modifier instead. It's not a fluid sim, but can look rather good.

There are several step by step tuts like ... https://www.youtube.com/watch?v=DmeCqQgj74Y$ FlipFluid https://www.youtube.com/watch?v=SWhPJmfLzNo ... https://www.youtube.com/watch?v=SWhPJmfLzNo ... so you would have to ask probably more specific.


text:
anyone knows how to make this cone tent in blender?
i got difficulty when making a cone shaped tent.
it is a combination of square and cone, i think.
i have tried so many times to make it but still far from the actual shape.

please click on "accept answer" so other users although know that the answer helped you. thanks.

Start by creating an 8 sides circle (move up) and a plane (4 sides)
connect them manually - three vertices from the circle to one plane edge.
extrude the bottom of the plane and create a loop cut in the middle of the edge - the loop cut won't go all the way up, you will have to connect the middle vert on the circle to the new edge using J.
now you will be able to add a loopcut across the faces, use LoopTools to circle the loop cut and scale it down a bit.
add few more and scale a bit more until you get the desired result.
this is what I got:

You can now collapse the top circle to one vertex or leave as is and just cap it and add a bevel and a subdivision modifier.
Result:

wow! i understand now.

thank you guys for your help. i feel like i'm really falling in love with blender that it literally can make ANYTHING.

You basically start with a plane.
Subdivide it using an odd number (Like 29)
Select the center vertex, use proportional editing in "Sharp" mode and pull the vertex up along the Z axis.
Select the outer vertices and extrude them down the Z axis.

You can also do this with a 4 sided cone which will make it a bit more realistic.

This way geometry gets stretched, not sure this is the right approach

I guess the cool approach would be to use cloth simulation. Anyway, we can always remesh I think.

could be, but might be an overkill for this object and also remesh is not great


text:
Weird UV after sculpting
after sculpting in blender i tried to import my model to 3D coat and substance painter but it has weird UV that results a very bad texture.
how to fix this?

Apply Transforms? idk, would be great to see uv screenshots within blender


text:
Emboss image with height difference
is there a way to emboss an image to a shape with height difference, for example with a 2D circle the center is the highest position and the outer is the lowest height?
*need to be applied not only on simple shape

You can use a height map on bump node via image texture. You can download height maps online or create your own. White areas will emboss more and it will reduce according to black and white.

as far as im aware its  only affecting the texture(?) is there a way to make it affect the mesh itself?

You may have to Convert Material Displacement to a Mesh which will be little bit complex. As you mentioned that "*need to be applied not only on simple shape" in my point of view Convert Material Displacement to a Mesh will not suitable on complex models.

Thank you for your responses, really appreciate it

@alvaro You could bake the texture (without displacement, just plugged straight into the material output) and then use the image as the texture for a Displace modifier.

To nondestructively displace a mesh, you use the Displace modifier.  The modifier takes a texture to modify the mesh with, which can be any of a number of built-in procedural textures; or you can use an image texture.
The mesh you wish to displace must have enough geometry to be distorted, of course.  Here's an example with a plane:

Create a plane
In edit mode subdivide edges to give it a lot of geometry.  Here I used 10 cuts.

Add a displace modifier

Left click the New button to create a texture for the displace modifier.  You can change the name if you'd like.

Go to the texture properties and make sure that Displace and your texture's names are selected:

I used example as my texture name.

If you want to use an image, select it using the Open button in settings. For this example I selected a built-in Clouds

If you are still in edit mode, the change won't show up, but when you return to object mode, your mesh will be displaced.


text:
Having Issues with Volumetric Fog
how are y'all doing? I have a slight problem going on with creating volumetric fog. Here's the story:
I was following along with a tutorial from Ducky3D and he got to a part where he started showing how to do volumetric fog in the shading tab. That's where everything stop! I did the exact same thing where my fog was there and the moment I add a noise texture node, it complete disappears. I played with all the settings on the noise texture and nothing. I search and review many other videos and questions in forums about this but nothing in close comparison.
Check this out:
This is from trying with a Mix Shader node mentioned and shown from someone's answer to another question on here

Here is what happens when I add the Noise Texture connected to the ColorRamp to the Mix Shader...Gone.

This is following along with the tutorial (don't mind the other nodes, just pay attention to the connections)...still gone.

However once I disconnect the Noise texture from the ColorRamp...it reappears.

I do not know if it is something I am doing wrong or some setup settings I need to setup in Preferences but I am at a lost and I need y'all collective minds because HELP!!!!!

There is a bug (https://developer.blender.org/T85778) that relates to the rendering of emission with non-zerodensity.... I don't know whether this could be related but I'm mentioning it anyway.

@RichSedman thanks for the mention of the bug but after looking at it, my only guess is that the Principled Volume node has a bug in it or something that pretends texture nodes from functioning with it because it works fine with the ColorRamp but the moment the texture node is connected, the fog disappears which is strange.

After further digging, found the culprit...it's a bug between Blender and the iOS system for Apple computers (EEVEE Volumetrics disappears when I plug in a noise texture to density node) (https://developer.blender.org/T65873) One that seems hasn't been fix completely yet but currently trying some work arounds to achieve volumetric fog
UPDATE!!!
Recently received a recommendation from an account from Youtube where I asked Ducky3D about this issue. Account name, Blender Fun. The recommendation was substituting the Texture Coordinate with Geometry from the "Input" drop-down menu in the Shading Tab. You can play around with the connections but if I remember right, everything below "True Normal" makes the fog disappear. However, this is a solution to create Volumetric Fog for Blender users on Mac, iMac, and Macbook.


text:
Seeing colors properly through colored glass
I have this simple model of a youtube Icon and I'm trying to make the red part transparent red but at the same time see the white triangle pure white.

Why not putting the white triangle outside of the red jelly? Or both a bit like a stained glass, white solid triangle in the center and red transparent around  ?

You could use the Compositor to overlay the 2 objects

if something like this is what you wanna achieve:

i used an HDRI and i "cheated" to get the white color of the triangle by giving it a massive emission:

Red shader:

this is with less emission and a bevel for the red part:

That's a good idea. Thanks for the help.


text:
Object to hexagons
I want to change a model into hexagons. looking for a similar result:

Is there a way to rearrange the topology of any object to be made out of hexagons, sort of like the triangulate modifier but to hexagons instead of triangles?
Thanks in advance.

If you already have tris you can use dual mesh.
Starting with triangular faces such as an icosphere some tutorials use the dual mesh node to change the faces into hexagons.

In your example picture, a second step might be to split the edges of the faces, scale the elements, and then extrude them.

If we want to separate the extruded hexagons later, there is one problem, which is that they are not capped on both sides.  This can be solved by adding another node to create the missing face:

Another couple examples, using the triangulate node to change the mesh first:

This method does not always work, depends how evenly the triangles are stacked.  In an Icosphere it works very well.
I realize a more advanced answer or node group is out there, but this is a simple trick.

Is there a way to separate each hexagonal to be a different object?

Well, I have two ideas about that.

You could apply the geometry node modifier.  Then,  select the whole object, and press P to separate by "loose parts".  This would make each hexagon a completely separate object.   This would work if your tree is "triangulate>dual node>split edges>scale elements>extrude>group output".

Or, if you want to keep it as one, but track their IDs you could do some research into how the index works in geometry nodes.  There are many related questions.  The user Quellenform has a good answer concerning hexagons.

https://blender.stackexchange.com/questions/264036/how-can-i-create-a-hexagonal-structure-with-geometry-nodes


text:
Is there a way to assign dynamic paint canvas to a vertex group
I want to assign dynamic paint canvas to just a vertex group instead of the whole object. is there a way to do so without having to separate the vertex group?

I used the Waves option of the Dynamic Paint modifier, but for the Paint option you can use basically the same method, just store and write to the vertex color instead of the position.

With Geometry Nodes, you can save the original position of each vertex before the Dynamic Paint modifier and then after it mix the current position with the original depending on a weight group.

If you don't need the waves to reflect at the border of the weight group, you can simply mix the original and deformed positions:

But if you want them to reflect, the regions must also be split before the Dynamic Paint and then, after it, merged together:

 $\text{Blender 3.6.5}$

Very good walkaround thanks


text:
Shape key depending on another
If I have a shape key that extrudes the mesh upwards. then I want to make another shape key that will extrude the mesh(which is already extruded upwards) sideways, when I try to do so, only the original vertices can be edited not the new one created by the first keyframe. Does anyone know how to do that?

Shape keys do not support operations that create new geometry. You can imagine them as just a list of vertex coordinates for each vertex that was present at the time the shape key was created. If you create new vertices by extruding, the shape key you made previously won't have any reference to those.
A solution to your problem is doing all the extruding first and then creating the two shape keys afterwards. Select the second shape key, go into edit mode and then move the part of the model you extruded sidewards back to its original position. With the second shape key set to 1, select the first shape key and 'undo' the movement of the first upwards extrusion. Now you have two shape keys that "extrude" your mesh, albeit with inverted values.

Note that in doing so, you need to think about how it will look while the fake extrusion shapekey is disabled: overlapping geometry might produce z-fighting issues.


text:
Stretch cloth to a limit then tear
I was wondering if there is a way to make cloth stretch to an extent and then tear. For example: have cobwebs(cloth) sticking between an object and wall then, the object starts moving so the cobwebs stretch with the object to a limit, and then it tears (if not possible They can just leave contact with the object).
Thanks in advance.

$addon

Nice thanks but how to stretch it

It looks to be a tricky (probably try to contact the author)... basically I tried to Hook "Plane_Original" object, but behaviour is weird. Without addon I was partly lucky with Sewing feature, but cut is not broken completely -connections still drag the cloth ... now I'm playing with Tension Map (procedurally under GeoNodes) that sounds like the right direction, but in Cloth combination it seems like some circular dependency or  what ever ... I will give it a try this afternoon.

Procedural Tearing
So I got something (not ideal), but looks like a working concept ... Tension Map used as factor for Split Edges under Geometry Nodes.
Tension Map
I used geometry node group developed by CGVIRUS studio (here re-colored to better see just stretch part) ... general issue with that (with tension, node group is great) - the most stretched (red) part is the dragged corner, that is not what we want (to just tear the tip of cloth).

For that I painted another Weight Map (stored in Vertex Group) with "fragile" part at centre ... so when mixed together with tension map you get something like this (tension at top edge).
Or  you can paint your place of tearing (called Custom in my file), just switch to Weight Paint mode, don't forget to change it than under geo modifier panel Tension Map > Weight Paint.

Tearing
To make it all works I had to use three planes here ...

The first keep it as it is to be used as a reference for Tension node group (I will check that later, there has to be easier way to access original vertex position to compare, I did it somewhere already).
The second plane with Hook, Cloth and GeoNodes>Tension modifiers
The third plane is used for final result - Surface Deform, GeoNodes>Tearing, Cloth modifier (modifiers used in this order)

Notes:

there was an addon for Tension Map, it just didn't work for me under 3.4 (I will check if there is not newer version) addon doesn't need to keep original mesh so on one hand cleaner scene, but for future you would have to care about external addon :)
Even I Weight paint an edge to be split it always split at least face. Those middle faces in place of tear just faults down so I added Separate Geometry node that "deletes" this part
Luckily for us the "delete" quite nicely compensate missing back stretch of teared part of cloth. Since geometry is changing for cloth sim at every frame, blender continue to sim from that point without knowing about stretch anymore here.
There is quite nice hack of tearing based just on a few modifiers, check last video tut
Or there was a build of Blender 2.79 with Fracture Modifier that had Cloth Tearing feature (still can be downloaded, just for Mac user -like me, I could not find it there).

Thank you, this helped alot If you find a solution for the middle part keep me posted please

OK updated ... check also note links.


text:
Different looking objects
Just a quick question. why do all professional YouTubers have this different look of blender objects.
for example:(screenshot from a tutourial by ducky 3d)

while mine looks like:

I'm talking about that hard look and white border that looks like bevel

It's the Cavity option in the Viewport Shading panel:

Thanks but what exactly does it do other than that??

nothing, it just makes your object look different if you think that it's more convenient


text:
Is there a way to use lighting in a scene with an image texture without changing any of the colors in the image? (Eevee)
I am new to Blender and I'm trying to put this thing into a video, but the final render in the video has different colors than the regular image because of a light source. Is there a rendering method or a way to prevent colors from changing from a light source?

Couldn't find a duplicate, but I'm sure similar enough questions have been asked.

[...] use lightning [...] without changing [...] colors in the image

Changing colors of a texture is called shading:

Shading refers to the depiction of depth perception in 3D models (within the field of 3D computer graphics) or illustrations (in visual art) by varying the level of darkness. Shading tries to approximate local behavior of light on the object's surface [...]

Therefore if you want to remove such behavior, you want a shadeless material, which you achieve by removing a shader:

The concept "color" of most peopel is a bit unspecific. Color splits in Chromaticity and Luminance. If you light something brighter you increas its Luminance therefor changing its Color.

As mentioned in the Answer about Shading... you can avoid this using a Shadeless Material.
Aditionaly in the Render stage your Colors go through a Color Transform.
And Finaly your input texture and Saved Output File have a Color Space.

This ar all complex topics on there own... and you have to get everything right if you want the same "color" out .. as you put in... I wish you a nice journey:
https://blender.stackexchange.com/a/92301/47253

You can use an Emission Shader for your image object. Eevee doesnt support shader based lighting, so you only get the absolute values of your image.


text:
How do I instance a small object evenly along a complicated shape?
I made this mathematical mesh and I'd like to add 10 regularly spaced small spheres along each of its curves spiraling out from the center, like the highlighted one. The problem is that the vertices themselves are not evenly spaced (they get farther apart toward the outside).
How can I do this?
At first I thought I could use the instancing tool but I definitely don't want one sphere per vertex.

one way you can do is duplicate the selected vertices, separate as new object and the give it a geometry modifier and use poisson disc with the distance you like and very high density.

@Chris thank you, how do you do that for a set of vertices? I can only get points distribute to work when the points are distributed over a volume mesh. On a line I don't see any generated points.


text:
Get Alembic Frame range from imported file via python
Is it possible to use python to get the frame range stored in an imported alembic file? I assume it's on the cache datablock but I can't see anything that would yield this information.
many thanks

do you have some answer to this question?

Only thing I could think of was save the current timeline range, then grab this again post import as Blender sets the timeline to what is in the imported file. You can then restore the original range and have the Alembic range as a variable


text:
Adding linked shaders from the Asset library with python
is there a way to assign shaders that are in a linked asset library? Iterating through the scene the asset lib shaders are not present - and as a linked asset, this scene link only seems to be created if I manually drag from the asset browser onto the geometry. Is there a way of doing this via code, so I can assign library shaders via Python?


text:
Change the linked node on a node group using Python
I'm trying to figure out how to change the linked node in a node group on a material via python
bpy.data.node_groups['Group_Shadow']

I'd like to do the equivalent of picking a new link via here -

Kinda similar to my other answer there.
It's not that trivial because some nodes change their displayed name depending on what they are representing. Group nodes are used to modify node groups but a node group is an actual standalone node tree.
So the green node you are seeing is not actually the node group it represents, but a virtual link to it. You can enter a new interface to modify the sub-node tree it is linked to, by using TAB or clicking on the icon on its top right corner, but they are two different entities.
That being said, you'll need to know your group node's unique identifying name, which is different from its displayed name, which is the sub-node-tree's name.

import bpy

ao = bpy.context.active_object
m = ao.active_material
nodes = m.node_tree.nodes  # Get material nodes
gn = nodes.get("Group")  # Get the group node (Name is case-sensitive)
gn.node_tree = bpy.data.node_groups.get("NodeGroup")  # Change the group node's node tree

That's awesome, many thanks. I had been circling around querying the node_tree, thinking there would be a list on some property. The notion of get rather than set here would have taken me an age to figure out, if at all. Cheers.

Well you can also do bpy.data.node_groups["NodeGroup"] but using get prevents throwing a KeyError exception if the name can't be found. Instead it simply sets the group node's node tree to None


text:
Problem with animating a character with no limbs
I tried to make a player character akin to Rayman, and after trying to create an idle animation and exporting the file in .fbx the animation bugged out and animates only a part that is not even animated in the first place, and is in a spot that shouldn't even be.
However, I did try to animate without a skeleton, would that fix the problem?
I am new to blender and game developement, I basically picked it up 2-3 days ago and I've been grinding ever since, so if someone could also explain to me why this happened for the future I would be grateful.

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

Hello and welcome! Can you add more details on how you rigged the model, which game engine is used, does the animation work in Blender, is the model one object, etc? Reading your questions let me know: you made a nice Rayman-style character, the idle animation doesn't work when exported as FBX, and you're new to Blender. Not enough information to answer the question.

I didn't rig it at all, I use the unity game engine, but the picture is from the built in 3D model viewer for windows (looks the same in Unity too though), the animation works in Blender, the model is several objects, one for each body part, I don't really know what else I can add to this, like I said I'm new and learning as I go so I'm not yet familiar with all of the things of the program.

Hmm, I'm still not sure what you did. Have you created the model in Blender, exported it, and animated it in Unity? ... maybe checkout Imphenzia's channel. He has a lot of Blender and Unity videos like this one https://youtu.be/pwZpJzpE2lQ.

It appears to have fixed itself when I added a skeleton


text:
Inconsistent UV-surface sizes on different models
My workflow starts in Blender (v2.93.0, OsX), where models are exported to GLB/GLTF and then imported in a web application running ThreeJS.
I have a bunch of products, all similar in size. Some have more extra details than others, creating larger UV-maps.
The problem is that the level of complexity in the products creates UV-maps where the similar parts get different amount of space in the UV-map. The result of this is differences in the textures.
I unwrap using Smart UV-project.
Is there any way of controlling a specific face/surface's percental coverage of the total UV-map? That way I can make sure all products have the same look, no matter of their complexity level?

Not sure what you mean by "complexity level". Using smart uv project is a bad idea in general because you're wasting a lot of UV space, I'd suggest unwrap the objects properly. Anyway, I guess your actual issue is a non equal texel density right? There is an add-on which might help: https://github.com/mrven/Blender-Texel-Density-Checker

@brockmann Complexity-level is the amount of faces. Some products have extra details that takes up more space than others in a UV-map. Causing the common areas to vary in size.
I also bake AO-maps with a margin of 1px, that's why I use Smart UV Project which let's me add margin for all UV-islands.
Will take a look at the plugin. Thank you!


text:
Blender Internal: normal map facing wrong on barrel mesh
I made a barrel model from a Sphere and textured it normally, but the Normal map generated from the image (InsaneBump) looks displaced and weird. It shows some strange stuff, like this:
Object mode:
You see that the top is displaced and the sides look like the sides of a sphere. Different projections didn't change the result. What am I doing wrong?

could you upload a .blend on blendswap? From those screenshots alone its a bit tough to figure out the problem^^

@Chris here it is link :)


text:
composing green screen video behind objects in 3d scene

please as you can see from the image, i want to compose myself behind the desk but the nodes available can only move the image in y-axis (vertical) and in x-axis (horizontal). There is no node to push the image backwards.
please if anyone has solution to this, i will very much appreciate to see it.


text:
Subsurface modifier problem in blender
I have a problem with the subsurface modifier. I am new to blender.
The modifier does this:

I know the reason. It's because I have some geometry on the back:

So on the back I have a corner. This is the top view:

I know I have a problem with the corner from the top too but that is a different problem that I need to fix.

@cegaton Thanks for the info. It fixed my problem.


text:
Which shader to use when baking normals?
I wanted to bake normals from a sculpt onto a lower poly mesh into a texture. Then I found out that the shader used on the source objects affects the resulting normal.
So I tried making a new project, made a plane with a noise texture for a bump map, another with a texture, and tried baking from different shaders from first plane to the second, and got different results:

It appears that Diffuse BSDF's normal map looks most contrasted, Glossy's is smoother, and Principled's is somewhere in between. Enabling coat for Principled produces a fourth result, smoothest of them all.
Roughness settings doesn't appear to change much, but IOR setting on Principled does. I suppose Principled just combines Glossy and Diffuse based on Fresnel with set IOR for this, which is why it looks in between of the two. Changing shadow terminator settings on the source object doesn't affect much either.
Anyway, this all leads me to my question. Which shader should I use when baking normals from? What's the reason for the difference between Glossy and Diffuse? Is it a Blender bug, or there's some actual consideration to make?


text:
I want to join two objects but subtract the parts that will overlap
I have a hollowed out irregular bowl shape with a specific thickness that I want to stick a rectangular solid handle on the base. Ideally it would completely surround the end of the bowl shape but I want to maintain the inside hollowed out form of the bowl.
When I try to push the shapes together, the solid filled handle overlaps and fills inside the bowl it is joined to. I was wondering if there was a way to maintain 100% integrity of the bowl whilst freely adding the solid surrounding handle?

an image with what you want you have would be very helpful

thanks ok ill upload

I think its Boolean difference maybe? Im looking for videos right now on YouTube

i still don't get it....or do you want this? [1]: https://i.sstatic.net/TPYEr.png ...yeah, it is a sphere, not irregular...but that way?

 but I want that inside removed not maintained. Maybe I will have to make the main bowl solid first, do the boolean difference and then hollow the bowl again afterwards?

yeah that way but my shape is a bit more complicated as it has a slit down side so the boolean method is just subtracting the part that is in physical contact

I want the rectangular surround but maintain the hollow centre inside if that makes sense

i know you meant irregular...so like this, right? [1]: https://i.sstatic.net/sosYO.png

Yes, did you see the picture https://ibb.co/PtM5jqv

The solution to your problem is: duplicate your irregular part. Then close the top face.
Use this as boolean modifier object and just hide it in render and viewport display.
example:

duplicate that object and close it:

move it to the box

give the box a boolean modifier with the closed object:

set visibility of closed object:

result:

put back your original object:

Hint: "normally" you wouldn't move the original and the cutter object, i just did it here that you can see which object is which.

That's amazing thanks so much I will give it a go :)


text:
How do I make shell splashes and large calibre gun fire?
I'm working on a new project about a world war two destroyer called HMCS Haida. I've been playing around with particle systems and smoke/fire domains but all of my renders come out looking unrealistic.
For example, my most recent render came out looking like this:

It's a major improvement over my previous attempts but it still looks very un realistic. For reference, I'm attempting to create an effect similar to this:
World of Warships: Naval Legends HMCS Haida.
Obviously I do not own this footage, all copyrights belong to Wargaming.net and I only clipped it for example purposes.
I've also been trying to create more realistic water/ocean scenes. If you have some idea of how to create that kind of water explosions (from shells landing) please share, the best I figured out is to create a smoke domain.
In my opinion the water appears too glassy. Water in the turbulent ocean shouldn't be so mirror like. Advice, criticism's and suggestions are all welcomed. I'm still rather new to Blender, but I want to make this project look as professional as possible.
Thank you for taking the time to read this, I look forward to your responses!

Is this for Eevee or Cycles? How do the shaders for the fire and the water look like?

It would be nice if you could tell us what render engine you are using and show us the shaders for your fire and water.

Sorry, forgot about this post until recently. I'm using the cycles engine. https://imgur.com/a/e0yK42e Shaders.


text:
Distribute instances on plane faces, and make Instances face the borders of the mesh using Geometry Nodes
I've been looking for a way to distribute instances on a mesh and align the rotation of each instance to the direction of the border it would be place at. For instance:

On this exemple, "A" is the current result I'm in, a simple "Mesh to Points" > "Instance to Points" distribution.
The nodes look like this:

"B" is the result I'm looking for. Where the instances face the border edge of the face they're instanced on.
The final goal of this would be to distribute houses and buildings on a large scale neighborhood in a more accurate way, where they all face the correct direction and using plane meshes for every city block
"C" is a most advanced version of what I would need, where a larger plane can be used as source mesh, and only the faces touching the border of the plane would be instanced on, leaving an empty space in the middle. but don't know if it is possible, so "B" would be fine for now.
I'm not the most advanced user of Geometry Nodes, quite the opposite really. I learn the most I can from tutorials and try to apply the principles learned to my specific problem, but I haven't being able to find any sort of reference on how to create this specific type of alignment. I would appreciate any solution or direction on how to achieve this.

Easy. Use a switch to store a vector attribute in face corner domain. If Edge Neighbors = 1: store (self_position - face_position), otherwise store <0, 0, 0>. Then interpolate this attribute to faces. Now for each face the attribute is either <0, 0, 0> (internal face), or a direction towards the edge (can be diagonal, but it's easy to detect such case and then multiply by <0, 1, 0> vector) Then Align Euler to Vector using this direction.

Oh, a single face is a special case with <0, 0, 0> direction like with internal faces, but I guess it's not hard to support this special case.

@MarkusvonBroady I don't know how much experience Paulo has with Geometry Nodes, I'm quite good at Blender in general but not GN in particular. Could you elaborate this to a real answer? How do I "interpolate this attribute to faces"? The only thing I get is the corner tiles pointing diagonally outwards, all others stay the same...

If the grid height = 1, make all arrows up (the input geometry is a tile with an arrow pointing up, that is $+y$).
If the grid width = 1, make all arrows point left (just realized maybe you want the top to point up and bottom to point down, but it's the easier part of the tree…)
For all other cases as I wrote in the comment.
Detect borders by checking number of neighbors = 1 and capture that on edges.
For the face corners lying on those borders, capture the difference of their position and their face position (direction from face center to border-face-corner).
For face corners not lying on the borders, just capture $<0, 0, 0>$ vector.
Convert faces to points, so the face corner attribute interpolates to face domain, and then is copied to newly spawned points positioned at faces centers.
The interpolation from face corners to face simply averages the directions.
On a side it's an average of two same directions and two zeroes, making it still the same direction just with half of magnitude.
On a corner the average produces the direction of the corner, which is the problem Gordon Brinkmann mentions.
On a face inside, all corners have zeroes, so the average is also $0$.
Spawn the input geometry (the tile) on those new points.
I wonder if someone reads those walls of text.
Check the length of the averaged vector is bigger than zero (the $0.1$ value is just a threshold for precision-related safety).
Convert the boolean to integer implicitly: false = 0, true = 1.
Use the integer as an index of the instance: 0 is the just created single quad, 1 is the input geometry (arrow tile).
Set the rotation by aligning Euler to Vector.
The vector to align to is either the original vector, if there was no $y$ component (so either left or right), or the vector with $x$ component removed (as I wrote in the comment; so either up or down).

Vertical line patch

Markus I can't believe how detailed and thorough your answer is.
Thank you SO MUCH for taking the time to not only explain, but to also document and illustrate your answer!
I'm new to the forum and having my first post answered so thoroughly and with so much care leaves me with no words!
I'll be studying your demo file as I'm sure there's a lot to learn from it.
Once again, you have my total appreciation! Thank you so very much!

This is perhaps a much more reasonable answer, instead of mental gymnastics, just calculate and spawn 5 zones separately:

Markus, do you want your other answer to be downvoted? seriously... ; )

@lemon I'm thinking about writing a 3rd answer…


text:
Animation...why is it being added to my objects
Everytime I Duplicate an object, scale an object it apparently adds a key Frame to my object. I have no idea why. I am not doing any animation nor ever have.
I can delete the animation key frame by menu option in Object Mode: Object/animation/ClearKeyFrames.
Can't find any setting that I may have accidently changed.
Assistance would be appreciated

Are you using the default Layout workspace which has a timeline below the 3D workspace?  If you are, it's possible that you accidently clicked the white circle in the timeline header that means 'automatically generate keyframes'.  Try clicking it once to see if the problem stops.

Thanks for your suggestion. I closed the timeline space in the 3D workspace as I don't do any animation. However, just opened and noted that the white circle was actually highlighted. Turned it off and now OK. Don't understand why is was highlighted. Is there a shortcut that I may have used in error ?. Thanks

No shortcut that I know of, but it's something that people sometimes accidentally click without noticing.

Click on this white circle to disable "auto keying" and blender will stop automatically adding keyframes.

Adding @Marty_Fouts comment as a formal answer.