text:
How do i go about making a 3d smile that conforms to a sphere
I am currently attempting to make an original 3d character and i am having trouble making a smile that pokes out of the sphere.
My current attempt was as follows:
-I added a 2d plane and traced the 2d smile (half of it, using mirror modifier)
-I added a solidify modifier to give it thickness
-I added a proxy plane which i subdivided via loop cuts
-Joined the proxy plane with the smile plane using ctrl p and selecting object (i selected the smile plane first)
-Added a surface deform modifier to smile plane and bound it to the proxy plane
-Added a shrinkwrap modifier to the proxy plane and gave it the head as an origin
-The result was not what i wanted so i played around with scale, subdivison, thickness etc to get to the point i am currently at.
I also tried creating the smile first and then just giving it the shrinkwrap modifier but that did not yield the results i hoped for.
It is almost at the point i want it to be, however the sides at the top poke out which is not intended, the smile is not "droopy" enough and the entire smile goes to high. You can also see that in the middle of the smile there is a bump which also appears at the bottom side of the smile.
If i try to delete certain faces or vertices the entire smile gets messed up. I also believe that the topolgy is quite messed up and will be an issue when trying to add the "teeth" and rigging.
I feel like i am complicating and that there is a really simple solution.
How would you guys go about creating the desired effect?
(images below for my reference, the current state and the topology of the smile)

I want it to look like it looks now, so a 3d object poking out of the head and then either the lines in the smile in the reference photo would be indented or the space between the lines further extruded (probably the first option but i would like to see both)

First thing would probably be deciding how exactly you want it to look. It could be lines, it could be some solid geometry representing lines, it could be actual 3d form of teeth, it  could be just a material, could be empty space where the lines are... What do you want it to look like?

@MartynasŽiemys I want it to look like it looks now, so a 3d object poking out of the head and then either the lines in the smile in the reference photo would be indented or the space between the lines further extruded (probably the first option but i would like to see both)

This method is fairly straightforward: https://youtu.be/uqaxd9gMQMU?feature=shared

I would use some duplicated rotated geometry from the sphere itself and then shrinkwrap modifier to constrain it to the sphere while moving vertices and possibly applying the shrinkwrap a couple of times to correct the positions of verts. Relax function from Loop Tools add-on would be useful to get edges more smooth. I would make some geometry with flow of topology matching the teeth on the 3d sphere that resembles a mouth and looks like the reference from the front. Then it would be easier to make separate teeth from it. That would require the topology of the sphere to not be messy.

Proportional editing would be helpful while moving vertices.


text:
How to convert photo to relief?
Just curious if anyone has recommendations for using Blender and maybe add-ons to make height map from a shaded photo, so I can take a picture of a relief carving and reproduce it for 3D printing.

I think there might be AI models capable of generating height/depth maps. I think you could use Stable Diffusion with ComfyUI to do that. It requires some time to set up and a decent GPU though. If we are talking about doing it in Blender, it's just good old modelling, but that's a whole lot of work. I would go with AI. Maybe if you already had a height map generated by AI, somebody could help you use it to make the geometry. That part is quite straight forward though - just a dense plane and displacement modifier.

If you have access to real relief, you could also take many photos of it and use photogrammetry to make a 3d model of it. Have a look at Meshroom. It's free and open source. There is commercial software like Agisoft Metashape or Reality Capture that may be more mature, but they might be very expensive. Not sure, but Reality Capture might have a free version, you could look into that, if Meshroom doesn't work for you for some reason.

Ah, thank you, that might work...

ComfyUI's ControlNet Auxiliary Preprocessors Depth Anything2 seems to work Well... Somewhat. It might be amazing for regular surface displacement maps.

source: Stack Exchange

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

sort: votes


text:
What physics settings should be used to make a knot wrap up around itself?
I am trying to animate a fishing knot, and I need to know what physics to use to make the knot pulls on to tie up.

https://www.youtube.com/shorts/p5W0b6WLg-s

This animation looks too tidy to be done with physics, it was animated procedurally.

just give a Curve modifiers to a cylinder and move it along a curve that makes this shape

You don't need physics here. Create a curve (begin with a Curve Spirals > Archemedian, you first need to activate the Add Curve: Extra Objects addon). Create a cylinder, give it an Array modifier with a low Count and a Curve modifier with the curve as Curve Object. Keyframe the Array modifier Count value:

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


text:
New GPU not recognized by OpenCL and crashes often in simple render and shader mode in viewport, help?
GPU is 4070ti and only other updated component was my PSU for a higher wattage level. Previously was using a 2080ti that never had these issues.
When using blender version 2.93 (tried 3.0 as well and 2.79 but most of what I could find online mentioned OpenGL not being supported for these so I figured maybe that was the problem) now that I have a new gpu, suddenly it crashes every few minutes just moving around the viewport in shader mode with only a few primitives. This isn't a complicated scene at all. It also either crashes when I try to render or just does nothing OR resorts to using CPU and spikes to 100% immediately turning my room into an oven and risking crashing again.
OpenGL/GPU seems to be supported in rendering and denoise UNTIL I go to preferences to double check, then it's only visible under CUDA, but nothing is recognized in OpenGL or optix

What I've tried so far from what I could find online:

making sure the studio driver was what was installed from NVIDIA, clean install
benchmark test to make sure nothing else was running poorly I was missing
downloaded 2.93 blender but the most recent update to make sure it wasn't a bug that got fixed already
tried with blender 3.0 (all the way through to the current 3.5 version that's on the front page of the site, as well as through Steam)
made sure I have enough RAM, wattage, and my gpu was supported
made sure everything was on and set to compatible in NVIDIA 3d settings
tried that again but with high performance instead

even with nothing else running blender doesn't want to actually use my gpu and crashes every few minutes. It doesn't matter which version, and not other gpu heavy programs are having issues.

Why are you using such an old version of Blender? 2.93 is from 2021, pretty sure back then there were no RTX 4000 cards so I'm not surprised those aren't well supported. Also in you image it shows OpenCL not OpenGL, which is a computing API for AMD cards not supported on NVidia. as L0Lock mentions below.

@DuarteFarrajotaRamos yeah I made a typo. I was using 2.93 and other older versions that are stable to troubleshoot and make the point that this affects old and new versions of Blender: even if CPU is unchecked it doesn't seem to utilize GPU at all and skips over to just using CPU regardless of version

You should use the current version(3.5.1 now) unless you have a good reason not to. If you want to use the GPU for rendering, you should set OptiX for RTX 4070 TI card. Make sure latest drivers are installed for your GPU. Try regular drivers, whatever they are called, not the "Studio" ones. You should not touch any driver settings. Defaults should work fine, no need to "optimize" anything. If you have RTX card and it's not showing under render devices when you select OptiX, it probably means, there is something wrong with the driver, you could try different driver versions.

So did you enable your GPU in either CUDA or OptiX, and left either of them enabled in your preferences? Is your scene small enough to fit in your GPU to begin with?

@L0Lock yes my scene was just a few primitives with basic shaders as a test. Originally since I'm new to blender and was following a tutorial I thought this was something to do with OptiX or similar but had issues with any option, even CUDA (openCL was what was used in the tutorial)

an update for anyone reading this in the future with the same issue: it turned out to be an SSD/GPU issue that just happened to only really show when using blender and trying to render. Originally thought from a tutorial that it was the method of rendering I was using but turned out to be a few problems with windows update/nvidia driver interference/ssd issue.

check event logger and fix all critical, most were PFN errors.
I went through the steps to troubleshoot that and initially ran into more issues than just blender (so the late update), but eventually this is what fixed all of it including blender render issues.
using DDU to clean reinstall NVIDIA drivers worked better than Revo clean uninstall and reinstall
then in command line running chkdsk and then scan and check offline (requires reboot) is what ultimately worked

Had to dig deep online to find any helpful answers but it seems to be an issue that's caused by a conflict between NVIDIA driver updates + Windows update + new version of blender basically all not quite aligned, and chkdsk likely worked for me from file conflicts from what I could tell online.
Hopefully anyone else who has this issue this works for them and it's not such a nightmare to troubleshoot.

glad you figured it out.

Nvidia GPUs will use either CUDA or OptiX. Any "RTX" model will benefit from OptiX.
OpenCL was for AMD and Intel GPUs and was deprecated in favor of HIP and oneAPI back in 2021 for Blender 3.0.
GPU Rendering — Blender Manual v2.93
GPU Rendering — Blender Manual v3.5

yes but the point is that on old stable version of blender and on the newer versions my GPU isn't being used even where it is recognized and even when CPU is unchecked. Blender seems to override for some reason and just not use GPU at all regarldess of option.


text:
How can a single Curve Interpolation Mode set to Constant?
In order to animate a character so that it grabs an object an throws it, I added a Child-Of constrained and keyframed its influence. In the F-curve Editor I can't set the curve which controls the influence to interpolation-mode Constant without changing the other curves (Which should be linear or bezier).
How can the interpolation mode of a curve changed independently?

You can select left-click-select every single Key in the Graph editor and press T to change the interpolation. This will always only affect the interpolation up to the next key of that one curve.
Further controls for this:

A deselects all keys, just like in edit-mode.
L selects all keys of the curve of which one key is currently selected.
Tab locks the selected curve to prevent it from being edited.

Changing the interpolation type can be done per keyframe on a curve, the interpolation between the selected keyframe and the next defines the final curve shape. Selecting one keyframe and pressing L will select all keyframes on the curve.
If you are having trouble finding or selecting a single curve in the graph editor you may want to lock all curves and then unlock the one you want to change. Tab will lock/unlock all curves. You can also click the group lock (see green LocRotScale line below) to toggle all curves in that group, then unlock the one curve you wish to alter. With all other curves locked you can use A to select all the keyframes on the one unlocked curve.
The cursor button on the header of the graph editor can also help by only showing the curves for objects selected in the 3DView.
T will show the menu to choose what interpolation to use on the selected keyframes.

Also the Dopesheet and graph editor work similarly, you may find the dopesheet an easier way to select the keyframes you want. The same T shortcut will let you change interpolations in the dopesheet.

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


text:
What do the preferences keyframing options actually mean?

The reason I'm asking: It seems that I've fumbled too much with these options and weird things happen.I couldn't find any meaningful explanation in the docs.
What do these options influence, especially on keying and editing actions (poselibs)?

Auto Keyframing:
Enable it and create a new scene, add a cube for example, then move the cube, scroll to a different frame on the timeline, and move the cube again. Keyframes will automatically be created for the transformations (inserts a LocRotScale group if you e.g. use G to translate the object).
You can find the same toggle in the timeline header (icon only, red circle).
Show Auto Keying Warning:
If Auto Keyframing is active, a notice will appear in the upper-right corner of the 3D View during transformations, to inform/remind the user, that new keyframes are going to be added (if one confirms the transformation).
Only Insert Available:
Keyframes will be added to existing F-Curves only, and no new groups are implicitly created for you. So manually keyframe e.g. Location once, then change time and move the object around. Keyframes will be created for its translation, but not for rotation or scale, because rotation and scale don't have keyframes / F-Curves yet.
Visual Keying:
From blender wiki:

This is to be used with objects or bones that have
  certain constraints that can affect the key values. For example,
  setting a key on an object with a Copy Location constraint would
  normally set the key for it’s unconstrained location. Enabling this
  option causes the key to be set for the constrained location.

Only Insert Needed:

Will add keys only when needed (i.e. only to F-Curves controlling
  properties that are changing).

For completeness: the documentation on Timeline has more detailed information.

Only Insert Needed still missing, anyone? @stacker: I marked my answer as CW, 'cause I knew it was incomplete (missing 2/5 of what was asked for) and with room to improve my 3.

@stacker: that quote for "only insert needed" is pretty meaningless... doesn't really explain, and are there even IPO curves in Blender newer than 2.49? Don't we use F-Curves now?

I understand it this way: A keyframe will only be inserted when a property e.g. loc or rot is actually changed.

This is something that looked like a bug to me but I finally figured it out. Let's say you're animating a footstep. Set xyz location keys at frame 1, go to frame 10 and with 'Only insert needed' enabled move the foot on the x axis. Rather counter-intuitively keys are set for all xyz, not just x. However to to frame 5 and try it again. This time a key is inserted only on the channel that changed.
Ie it only works between existing keys. Seems like a design limitation to me as I'd expect it to apply to unkeyed space, but once you know it's still useful.

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


text:
How is the direction of interpolation determined?
I keyframed two poses and expected the arm to move upward (shortest way) like:

But what actually happens is that the lower arm moves the other way around to reach the second pose.

Is the interpolated movement always clockwise? Can the direction be influenced, or could there be some other reason for this behaviour?
I use quaternions if this matters.

The issue you are having looks like it's related to the way quaternion rotations work.
A bone in the rest position would normally have values of 1,0,0,0, a W value of 0.001 will leave the bone in roughly the same place, yet a W value of 0.0 will flip the bone in the opposite direction.
I'm pretty sure this only happens using quaternions when all 4 values are 0.0.
So it would appear that your animation curves manage to travel from positive to negative values to cause the flipping.
An easy solution may be to add a pose in between to define a pose between the two extreme poses, instead of having it take the shortest path.

Thanks, this was the closest thing, I just wanted to double check whether I mainpulated the W value, but actually I had set the rotation to euler (probably to check another issue).

I believe it depends on which direction you actually rotate it in in the 3D view. Try remaking it, making sure to rotate it in the same direction you want it to rotate during the animation (and not to rotate it more than 180 degrees).


text:
Render layer- or render pass-like options when you can't use Film | Transparency?
I have a scene containing

An object
An animated screen with an image texture/transparency material, which passes in front of the camera, adding a mist-like effect to the scene
A background/ground, etc
Environmental lighting

In the animation, Screen 2 passes in front of the camera, causing the scene to appear misted or muddy behind Screen 2.
I would like to "hold out" Item 1, the primary object, and produce a series of rendered images in which Item 1 appears as it does with the "screen" down but the remainder of the image appears at each point to reflect the screen's progress.... making the rest of the scene progressively mistier.
The rub: I need the cube to reflect the environmental lighting effects of the complete scene (less the animated scrim).... I can handle this in instances when my background can be transparent, but in this case I need my environment and lighting because of their contributions to my object.
This is a gimped up file, but includes the animated scrim.  All input welcome.

Is it possible to dissect this effect from a reference and show an example of the desired outcome?

The desired outcome portion of my sample image shows what I would like to have: The primary element unchanged by the mist screen, but those portions of the environment also behind the screen appropriately influenced.


text:
Rigging when bones must achieve conflicting goals
I have a question and words seem to fail me when searching here for an answer. Although this is related to a swim cycle, it is a problem I have encountered before: How do I achieve more than one goal for a bone: For example, a constant Y rotation, with a Z rotation axis saved as a separate action?
Here are details: I have created a swim cycle, deflecting a tail along the Y axis of three bones:

I would like to be able to add a flutter on another axis -- say Z -- and have that action smoothly intersect with the underlying cycle whenever and wherever it is used. Here is a Z wiggle:

In fact, I would like to do that with a flutter on the primary (Y) axis, too:

What I get, however, is the situation where the flutter action -- placed higher than the tail cycle on the NLA editor -- works fine, but ends up leaving the tail cycle deformed by the last position of the flutter NLA event. In the image below, the Z flutter has left the tail kinked downward:

My hope was to create action clips that added special or non-repeating action to an underlying strip but ended the "new" action -- the flutter in my file -- with a smooth return to the position of the underlying strip -- my swim cycle... Sort of like "take this cyclical position and add 10 degrees Z rotation, then subtract the rotation until it blends into wherever the underlying action strip is.."
So, that, with a question mark after it, is my question. How to achieve?

Hi rcgauer, I'm not quite sure I understand your question.  If you just want to blend the flutter strips out smoothly, you can always select the strip, change extrapolation to 'Nothing' and tweak the 'Blend out' field to ease out of that strip's influence.  Also in your file, only one of the layers isn't muted, so make sure they're unmuted.

Sorry... yeah: I understand they were muted... but I am going to try the extrapolation and blend out tweaks...

Actually, that is it... A combination of both, really... Some dialling in required, but this gets me there! Thanks

Glad it worked.  I'll add a more formal answer for anyone else looking.

To be able to 'ease out' of an action strip that's higher up the stack and back onto a lower strip's:

Ensure the higher strip's Extrapolation values (found in the properties bar) are set to Nothing.
Play with the Blend out fields (also in properties bar) to phase out of the Action strip's influence.  You can get a visual sense of how much easing is occurring by looking at the descending slope on the right part of the action strip (circled in picture).


text:
How to create a new catalog in the Asset Browser using Python?
Using this code gives an error.
How can I create a new catalog?
import bpy

bpy.ops.asset.catalog_new()

It's not exactly simple but here you go:
# Find the asset browser window
def find_asset_browser():
    for each_window in bpy.context.window_manager.windows:
        each_screen = each_window.screen
        if each_screen.name.lower() == "layout":
            for each_area in each_screen.areas:
                if each_area.type == "FILE_BROWSER":
                    for each_space in each_area.spaces:
                        if each_space.type == "FILE_BROWSER":
                            if each_space.browse_mode == "ASSETS":
                                return each_window, each_screen, each_area, each_space
    return None, None, None, None

# retrive the context of the asset browser
asset_browser_window, asset_browser_screen, asset_browser_area, asset_browser_space = find_asset_browser()

# set it to local
asset_browser_space.params.asset_library_reference = "LOCAL"

def add_asset_browser_folder(_):
    # open it with a context override
    with bpy.context.temp_override(window=asset_browser_window, area=asset_browser_area):
        bpy.ops.asset.catalog_new(parent_path='')

# use a timer to wait for the asset browser window to be ready
bpy.app.timers.register(lambda: add_asset_browser_folder(None), first_interval=0.1)

But this is the better way, by directly editing the 'blender_assets.cats.txt' (this way you can have names):
def create_catalog_if_missing(catalog_names, catalog_path):
    """
    Creates a new Blender asset catalog file if it does not already exist.

    Args:
        catalog_names (List[str]): A list of directory names that make up the full catalog name.
        catalog_path (str): The path to the directory where the catalog file is located.

    Returns:
        None

    """
    print_function_name()

    catalog_names = catalog_names[:-1]  # Exclude the last item assuming it is an asset
    catalog_file_path = Path(catalog_path) / "blender_assets.cats.txt"
    with open(catalog_file_path, "a+", encoding="utf-8") as file:
        file.seek(0)
        existing_catalogs = file.read()

        # Process each subset of the catalog_names for directory depth
        for i in range(1, len(catalog_names) + 1):
            full_catalog_name = "/".join(catalog_names[:i])
            simple_catalog_name = "-".join(catalog_names[:i])
            catalog_entry = f"{full_catalog_name}:{simple_catalog_name}"

            # Check if the full catalog name is already listed to avoid duplicates
            if catalog_entry not in existing_catalogs:
                new_uuid = str(uuid.uuid4())
                file.write(f"{new_uuid}:{full_catalog_name}:{simple_catalog_name}\n")

create_catalog_if_missing(["catalog_1", "catalog_2", "catalog_3"], "E:\\Blender\\FOLDER CONTAINING 'blender_assets.cats.txt'")


text:
Rendering worked one time and now is not working
I am trying to make PHP and Blender Python render a 3d model to a website in headless mode. My server is an Ubuntu Linux server on a DigitalOcean droplet.
This worked one time and successfully gave an output of the render. I deleted the png render to try again and it does not work anymore.
Using Blender 3.0.1 for the blend file it is trying to read and blender -v on Linux reads the same version.
Code:
<?php
$head = '
import bpy
import os
bpy.app.debug = True
';
$save = '
# Set the environment variable to indicate running in background mode
os.environ["BLENDER_OPTS"] = "--background"

bpy.ops.wm.open_mainfile(filepath="/var/www/projects/game/render/umi2.blend")

for ob in bpy.context.scene.objects:
    if ob.type == "MESH":
        ob.select_set(True)
    else:
        ob.select_set(False)

bpy.ops.object.join()

bpy.ops.view3d.camera_to_view_selected()

origAlphaMode = bpy.context.scene.render.film_transparent
bpy.context.scene.render.film_transparent = True
bpy.context.scene.render.filepath = "/var/www/projects/game/cdn/renders/avatars/53.png"
bpy.ops.render.render(write_still=True)

# Reset the alpha mode to its original value
bpy.context.scene.render.film_transparent = origAlphaMode

';
$python = "
$head
$save
";
echo "$python";
//echo "successfully rendered";
        $pyFileName = "/var/www/projects/game/render/render.py";
    file_put_contents($pyFileName, $python);
    //exec(escapeshellcmd("blender --background --python /var/www/projects/game/render/render.py"));
    $blenderCommand = "blender --background --python /var/www/projects/game/render/render.py 2>&1";
        putenv("DISPLAY=:0");

        $output = shell_exec($blenderCommand);
        echo"
Output
";
        echo $output."";
?>

Log: (When going to url to render it in background)
import bpy import os bpy.app.debug = True # Set the environment variable to indicate running in background mode os.environ["BLENDER_OPTS"] = "--background" bpy.ops.wm.open_mainfile(filepath="/var/www/projects/game/render/umi2.blend") for ob in bpy.context.scene.objects: if ob.type == "MESH": ob.select_set(True) else: ob.select_set(False) bpy.ops.object.join() bpy.ops.view3d.camera_to_view_selected() origAlphaMode = bpy.context.scene.render.film_transparent bpy.context.scene.render.film_transparent = True bpy.context.scene.render.filepath = "/var/www/projects/game/cdn/renders/avatars/53.png" bpy.ops.render.render(write_still=True) # Reset the alpha mode to its original value bpy.context.scene.render.film_transparent = origAlphaMode
Output
Color management: using fallback mode for management Color management: Error could not find role data role. Blender 3.0.1 Color management: scene view "Filmic" not found, setting default "Standard". Read blend: /var/www/projects/game/render/umi2.blend Unable to open a display Aborted (core dumped)

Any help would be appreciated, again it did work one time so I'm not sure why it's not anymore CHMOD is set to 7777 practically everywhere.

I've edited your tags. It is helpful if you are talking about python to have the python tag on the question.

https://blender.stackexchange.com/questions/294098/why-does-my-cube-not-render-in-python Seems related. EEVEE cannot just render without display connected to GPU. See https://blender.stackexchange.com/questions/150526/blender-2-8-aws-ec2-command-line-eevee-render/174537#174537

What is up with the outdated 3.0.1 version everywhere? Just use Snap Store or download current version from the website.


text:
Make object in glass material not look like its underwater?
My object inside my glass dome is just a normal cube, but when I render the image, my cube looks like its underwater. Is there a way I can keep the glass dome and and have my cube look normal?
render.png

If you're using a Glass Shader, try bringing the IOR closer to 1, but not all the way to 1 because that will cause you to loose the dome reflections.
Default IOR - 1.45 - Cube is bent

IOR at 1.0 - too low - Cube is normal but glass shape (reflections and refraction) is completely lost.

IOR at 1.10 - More realistic - Glass is still visible without bending the cube noticeably. However, notice the background is refracted differently as well - you will have to find an appropriate balance that works for your project.

Most likely your glass is just a single surface with no actual 'thickness'. This means that Blender will treat it as if it's a solid piece of glass with the cube embedded within it, which is why it appears as if the cube looks like it's in water (actually it's within solid glass).
The simplest solution is to simply add a Solidify modifier to the glass dome. This will automatically add additional faces to your mesh to make the suface have 'thickness' instead of simply being a boundary into the glass.


text:
How to do this type of trailing effects?
Here is an example of how I wanted to do those types of trailing effects as seen in this video:
https://www.youtube.com/watch?v=zXOAtC7MOLE

Now how do I do this effect in blender?

This might be what you're after - (top comment) - https://blender.stackexchange.com/questions/71400/motion-trail-effect-on-video-in-vse

The simplest (and worst quality) solution would be to just have a few colored texts flying with the same animation (but each next one having an increased time offset of the start of the animation), and then in GIF or APNG format, disabling frame disposing, so that the pixels aren't cleared before drawing each frame.

In order to reproduce the effect it is useful to know how it would have originally been produced.
At the time of the original effect being produced (early 1970s) there were not the digital tools available now. All video effect would have had to have been produced either via completely manual processes or via analog video editing techniques. In this particular case the effect is produced via video feedback where the existing image is fed back into the next frame so as to produce the 'ghosting'.
The video would have been shot in reverse (so the ghost images would have projected back from the text instead of coming out of the background) and the frame sequence reversed (by playing back in reverse). Multiple instances of the same shot would have been overlayed (with colour adjustment) and used to mask out the preceeding sequence so as to layer multiple colours over each other to produce the final shot.
We can produce similar results with a very similar (but much less labour intensive) process.
The first step is to set up the 'video feedback' to produce the ghosting. This has already been covered in https://blender.stackexchange.com/a/212906/29586 where it's used to feed back the previous frame for a 'life' simulation. The same technique can be used for other feedback effects.
Setup the scene with the camera pointing at a plane. Place your 'text' object (or whatever you want to 'ghost') in view of the camera.

Set the output path in the render output properties to a suitable location and create the material for the plane.

The Image Texture is set as a 'sequence', pointing at the same location as the render output location. The number of frames should be set to at least the number of frames of your animation and the Offset set to '-1' to indicate it should be one frame behind the render.
Rendering the animation should result in no change in the image (since the rendered image from the previous frame is the same as this current frame).
Alter the material so as to inject a difference between the frames and show/hide your text at appropriate times. I opted for a rotation, zoom and distortion - similar if this had been achieved with a 'real' camera, producing the following material and result.

Now the VSE can be used to combine and layer mulitple sequences together with Modifiers used to adjust the colours. The final frame is retained at the end for persistence.

Note that here I've imported the Strip from the relevant frames of the redered result. In the strip properties (on the right) the 'Reverse Frames' allows you to reverse the sequence. I've added a 'Color' strip at the bottom for a black background and set each of the 'layers' Blend mode to 'Screen' so that they overlay. Duplicating the strip and offsetting each duplicate gives the different 'layers' and the Modifiers can be used to adjust the colour with a Color Balance modifier.
This produces the following result :

no that wasn't I was looking for.

@cd20 Update your question with more clarity as to what you’re actually looking for if this answer doesn’t match. I’ve done my best to interpret what you were asking. More detail in the question will give someone more to go on as to what you’re actually expecting.

...or if you’ve solved it yourself just add your own answer and mark that as ‘accepted’ - instead of replacing an existing answer with an edit.

I already solved it myself with a different solution. So I think it's okay... :/

Fair enough. This site works by users taking the time to share their experience and help solve each others problems. It would be good if you could add an answer to allow others to learn from your solution.

I cannot reliably get this method working. This relies on blender to not care if the png files exist to use a -1 offset version of it, but blender, in my case 2.93, seems to not want to pick up on the offset generated png file to use. Also frequently the material colour turns magenta, indicating there is a problem with the material.

@placidchat It is a bit picky in getting the settings right. Make sure you've set you 'Output' path and thenrender a few frames using 'Render Animation' (manually stop once you have some frames). Point the Image Texture node at that image and then make sure to set 'Frames', 'Start Frame' and 'Offset' appropriately - if that's wrong then it will pick up the wrong or a missing frame. TBH, I don't know if rendering on GPU might cause a problem as it might cache frames -perhaps there's an issue with 2.93 also caching frames.... you could create a new question toask about that and link to this one.

Also, see https://blender.stackexchange.com/a/212906/29586 (linked in the answer) as that also sets up in a similar way and that might give you some clues as to what's happening.

After playing around with it. Yes it seems to work. The -1 offset will cause blender to render the first couple of frames with the magenta colour, after which the rest of the frames seem to work. If there's a problem with viewing the feedback, disconnect any mapping vectors into the image texture node to check first


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My character with soft body still go through wall a little (animation)
I have
A character with softbody (and ik armature if you are wondering),A wall,Collision enable
The character deforms itself on the wall as i want but some of the mesh still passes through the wall.
This would not be a problem but the fact is that my wall is a transparent glass and i do not want anything passing trough it since it kills the effect i want to make.
I tried a lot of tweaking with softbody(since tutorials are non existant) but a small part of the mesh still passes through  no matter what.
To put it more simply , how to make a wall that cannot be penetrated by anything , all other things are secondary.

At the moment this question is too vague to answer - we need to know more of how this is set up - preferably with screenshots, etc of the mesh, the setup, what’s going wrong, etc - as much as you can provide. In addition it would also be good if you could provide a simplified .blend file to make it easier for someone to replicate your situation (but this should not be instead of the additional detail).

I should have put it more simply , how to make a wall that cannot be penetrated by anything , other things are secondary

The blender physics simulation doesn’t work with absolutes, only forces - give something enough velocity or enough force and it will pass through a surface. However, there are some simple general things you could try - in particular, make the simulation work with smaller intervals so forces and velocities are proportionally smaller. This can be achieved by increasing the ‘Steps per second’ setting for the simulation. If you can provide a more specific example of your situation I can try and provide a more specific answer.

The blender physics simulation doesn’t work with absolutes, only forces so it is not possible to give a mesh a property that will absolutely prevent anything penetrating - give something enough velocity or enough force and it will pass through a surface.
However, there are some simple general things you could try - in particular, make the simulation work with smaller intervals so that forces and velocities are proportionally smaller. This should result in the collision having an effect before the impactor manages to get through. This can be achieved by increasing the ‘Steps per second’ setting for the simulation. For very fast simulations or extreme forces (such as a soft body string wrapping around another mesh) you may need to increase the steps per second by orders of magnitude (perhaps from 60 to 6000 or more). Increasing the steps will provide a more accurate simulation at the expense of requiring more simulation CPU time.
Other options are to ensure your Normals are set correctly and to adjust the collision bounds (eg, Soft Body settings) to be appropriate to teh mesh. For example, see How to get the physics engine to wraps a string around the moving part of a motor constraint


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Node to calculate angle to camera
I'm looking for a node that allocates a value based on the normal's angle to the camera (I've seen some people use it to fake fresnel), but I can't seem to remember what it was called, so was wondering if anyone could clue me in? Cheers.

Perhaps Layer Weight?

@lbalazscs I think that's the one!

You do know there is an actual Fresnel node right?

@PGmath Yeah. I'm not using it for fresnel though, and layer weight seems to be more flexible.

The Vector Math 'Dot Product' node takes two vectors and returns a Value based on the magnitudes of those vectors and the angle between them. If you pass this node the Normal and Incoming vectors then the result will be larger if the ray is along the normal and approach zero as it becomes more of a glancing blow. Specifically,
Dot Product = MagnitudeA x MagnitudeB x cos(angle)
So if the two vectors are Normalized (which can be ensured by passing them through a Vector Math 'Normalize' node) then the Value output by the Dot Product will simply be the Cosine of the angle between them.
This can be used to mimic the Layer Weight 'Facing' node as follows :

Or you can emulate a Fresnel effect by including a Power Math node :

Varying the inputs or manipulating the Vectors can achieve effects not normally possible with the standard 'Fresnel' and 'Layer Weight' input nodes.

authors: محمد حلمي السعيد ابوزيد


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Is it possible to make the image appear in the order of object number
https://www.youtube.com/watch?v=j5jUoLAXmCA&feature=youtu.be

This is a video of the Eiffel Tower that I made to appear by designating a frame myself.
but I want to frame automatically in the order of object number or creation so that they appear in the video.
So, I want to make a video that appears in order, one by one, block by block like the Minecraft building videos.
Is there a way to use an animation node or another way?

the build modifier does this kind of thing but it's face by face (if you join all your objects), not object by object

The AddOn Animation Nodes and "ID Keys" can achieve what you want. Check out here: https://www.youtube.com/watch?v=s4wcSW-e_Pg

I thought at first about achieving this using Drivers but it's too difficult to clone the driver to each object visibility without resorting to scripting - so I figured why not just use scripting anyway.
I'll vary by height as it's simpler - but you could tweak the code to change the order of visibility to use some other property (could assign a property to each object or use the position in the list of objects (which will relate to the order of creation).
Start by creating a new Scene custom property named 'Height' and set it to be able to vary over a suitable range - this should be keyframed to reveal the objects.

Next, open a Text Editor window and paste the following code in a new text block named 'hideshow.py' :
#Hide objects above some threshold
import bpy

def frame_change_hideshow_objects(scene):
    height = bpy.context.scene["Height"]
    for obj in bpy.data.objects:
        if obj.location[2] > height:
            if obj.hide_viewport != True:
                obj.hide_viewport = True
                obj.hide_render = True
        else:
            if obj.hide_viewport != False:
                obj.hide_viewport = False
                obj.hide_render = False

bpy.app.handlers.frame_change_pre.append(frame_change_hideshow_objects)

Click the 'Run' button (a 'play' button in the header) to execute the code and it will install a “handler” to run on each frame change. Each time it runs it compares the value of the scene property ‘Height’ with the Z coordinate of each object in turn, flipping the visibility based on the height if it has changed.
Now keyframe the new 'Height' scene property to vary over your range. Play the animation and your objects will show/hide based on whether they are above or below the 'Height' :

In order to use the image id instead of Height, rename the scene property to something appropriate (eg, 'RevealID') and amend the code to compare that with the point in the list of each object (ie, the number of times around the loop) :
#Hide objects above some threshold
import bpy

def frame_change_hideshow_objects(scene):
    revealId = bpy.context.scene["RevealID"]
    objcount = 0
    for obj in bpy.data.objects:
        objcount+=1
        if objcount > revealId:
            if obj.hide_viewport != True:
                obj.hide_viewport = True
                obj.hide_render = True
        else:
            if obj.hide_viewport != False:
                obj.hide_viewport = False
                obj.hide_render = False

bpy.app.handlers.frame_change_pre.append(frame_change_hideshow_objects)

In my example this produced the following result. Note that the objects were created using 'Grid fill' particles so they are created in an uncontrolled sequence (this is why basing on height was simpler!!) :

For better results you would need to take more care in the creation order of the objects than I did - or re-sequence the objects in some way. Alternatively, use a method of revealing the objects that isn't based on the creation order such as by height as described above, by amending the code.


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How to create a rope
I have a buoy on the surface of a fluid simulation that moves around.
It has no Rigidbody attached, only a few rotation and location constraints which should cause no problem.
I am wanting to create a rope that attaches to the floor of my simulation and the buoy. It should fold relatively naturally as the line slacks. I have attempted one tutorial which got me close, creating a rope that bends and is affected by gravity, but it breaks if I try to attach the end to the buoy. (Link Below)
https://www.youtube.com/watch?v=ydX7bzLFbTo
I have tried hooking a bezier curve but it didn't want to attach to the vertice. (The little icon said I couldn't :( )
If anyone has any tutorials or ideas, it would be great if you could post them.
I have a relatively good knowledge of blender though I am a bit vague on where to find buttons and such :)
If any additional information is required I will help where I can.
EDIT:
Apologies, but i am on a school laptop and websites like imagur.com are blocked, so no images :(
FYI, i wont see yours either, sorry ;P
My fluid simulation is basic, restricted by the domain and a starting fluid object and some small waves.
I have a small plain subdivided with shrinkwrap on it wrapping to the fluid domain, so it 'follows' the surface
I then have a buoy that is constrained to that small plain by z axis and all rotations so it seems to "float" on the surface
I have another Plane on the floor with a passive rigidbody and collider
Now the string (this is what i did):
I had a single edge, one vertex at the buoy, another on the floor. I then subdivided it 30X. I then saved each end point separately to a vertex group. I then hooked the vertices to the floor and buoy (I also tried empties). I added the softbody simulation and followed the steps in the link (maxing default and stiffness). The rope held place but only the first vertex moved when the buoy moved. I then tried disabling goal, getting a realistic rope effect, with no edge stretching as should be, but both end vertices would not stay hooked.
Im stumped, but this is the closest I have gotten.
I don't have any add ons if that makes a difference.
If you want to know any preferences or settings of blender or solo objects, just ask :)

Does it have to be rigid body? While it can be done with rigid body constraints and then hooking a curve along the chain of rigid body objects, it’s probably simpler to achieve using Soft Body. See https://blender.stackexchange.com/a/98438/29586

Related https://blender.stackexchange.com/questions/100642/wave-modifier-physics

Thank you Rich, I had never thought of this, I will give it a shot and see how it goes, and yes I do require the rigidbody as it must not fall through the floor, but it should be little problem with what you suggested.

Thankyou Rich, this is the closest I have gotten, but the rope i have made falls withought being pinned to the empty. It stays when I use goal, but it doesnt move like i want it to. I have constructed it as multiple verticies in a line and it works great as a rope but i just can't seem to get the end vertice to attach. Any ideas?

@BigfootBlondy without seein your SB settings it's difficult to tell. Yoo need to use the goal pin setting (using a vertex group that just has those hooked vertices) to pin the hooked vertices in place and set the goal strength and stiffness so those SB vertices stick to the hook. If you can share some details of your setup I should be able to help.

I added more information to the original post. I am absolutely stumped. It's probably something basic but surely it is possible to do this...

Have you set the Vectex Group in the Soft Body Goal to the vertex group that you have added your end point vertices to? This is what tells the soft body which vertices to pin and which to leave to be free to move.

Also related

THANKYOU!!! can't believe I missed that. Many thanks for the quick responses, very good for my first help request!

Many thanks to Rich for helping me solve this!
I created a single edge at the length I wanted my string/rope. I then subdivided it till I saw fit (will not look choppy).
Create three vertex groups:
  One for one end, one for another, and one with both (in my case
  pin_Float, pin_Floor and pin_Ends)
In turn, click on each control object and hook to the specified ends (not the double ended one ;) )
Add a soft body to your string and set 'default' and 'stiffness' under the 'Soft Body Goal' to max. Then underneath assign the vertex group with both ends to 'Vertex Group'
Play and adjust the settings under 'Soft Body Edges' until the rope moves as required
I also applied 'Soft Body Self Collision' and a Skin modifier
The Rigidbody and Collision physics can also be applied making it very easy to use.
Again, thanks to @Rich Sedman for his help.

What does this answer provide, which isn't found in the original answer? Currently, I don't see the difference.

I missed the part to select the vertex group in the soft body goal settings. mostly a minor error by me. I was just repeating the process in detail for anyone having the same issue I did :)


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Get pixel data from rendering in script using built blender python module
I need to get the Pixels of the render pass to convert them to a numpy array within a python script. From my research there are 3 possible ways to solve this:

using a viewer node in Compositor
using a GPU texture
saving to disk and loading image

I made it work using the first option like this:
pixels = bpy.data.images['Viewer Node'].pixels
arr = np.array(pixels[:]).reshape((height,width,4))

However as stated in a lot of other questions and answers (that are a couple of years old) this does not work when blender is in background mode or in my case when using blender as a built python module, since the rendering of viewer nodes was disabled for performance reasons when in background (Python render script different outcome when run in background). I tried fixing the source code according to the answer given in the linked question which solved the problem but now blender doesn't free some memory blocks (probably since the Viewer buffer is not freed in background mode).
Since all the posts asking this question are already a couple of years old and for Blender 2.x versions i wanted to ask if there is a better for solution for retrieving the pixel data in Blender 3 or someone has advice on how to fix the memory leak?

Any chance you figured it out? I need to render images very quickly, ideally without saving them to file, only using bpy, without opening the GUI. I found lots of questions with similar intentions but all dead-ends

@OrenMatar We ended up rendering and reading on a drive that was created on RAM. We used the standalone bpy from pip. When the question was created this wasn't fully supported therefore the issues. Should work fine in newer versions though.


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UV project on object without the projection on the back of it
I'm using a camera to reproject an image on a mesh using UVProject and a material with image texture + emission shader, and it appears that the image is also visible on the back of the object.
Do you know why and how to get rid of this projection on the back?
Many thanks
Edit: below is my UV editor
Blend file added

Hi mooboots, here it is

Could you please pack your image (File > External Data > Pack Resources), save and share your file? https://blend-exchange.com/

Okay, it's added

Oh OK i missed the UV Project thing, I'm not sure that you can avoid that, what were you trying to achieve exactly

I'm aiming at projecting multiples images from multiple point of view on the same object, using scripting. I have another camera for rendering the whole scene

UV project basically makes a flattened version of your mesh from the camera's perspective. If you do not want the back parts of your mesh to feature that texture, you have to select these part and unwrap them again, and move them somewhere in your UV space that doesn't show the texture.
In your material, set your image texture's repeat mode to clip so that the picture isn't repeated.
Alternatively, create a new material slot, assign the back parts to that slot and put a completely different material in that slot.

Thanks for the precision! I'm aiming at projecting images on the same object (a more complicated one), using bpy scripting. Therefore is there a way to select the front or back parts automatically, then? Btw in the images I posted the "clip" mode is already on.


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Every time I extrude 2 faces, a neon blue line appears, slightly askew, and blue. I need to extrude in a straight line. Help?
I was modelling a robot, with curved legs made of spheres hacked into 8 even pieces. I tried to extrude 2 faces to make part of the joint that connects 2 of the legs (named paddles for some reason), and a blue line keeps popping up, bringing the extruded faces upward slightly, while I try to move the extrusion backwards (-Y axis). Anybody know what's going on?

I forgot to mention, but the legs are sliced in a way that the top half has 4 parts, and the bottom half has four parts.

It's probably extruding in the Z direction because you'll see a blue line while youre extruding in that direction. Please add an image of your full Blender screen to your question so that we can see what's going on. In Blender, Window > Save Screenshot and then https://meta.stackexchange.com/questions/75491/how-to-upload-an-image-to-a-post.

By default the faces will extrude on their Z axis (face normal axis), if you want to extrude them on another axis, press X or Y or, in case you want to extrude on local axis, double X or double Y

or press z again to extrude along global z axis. u will see in the upper left corner that it extruding along its normal

thanks for the help!


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Why Is this artifact happening when baking AO?
I'm pretty sure I understand the simple process behind baking but sometimes I have hard times as such because of these weird artifacts.
And topology is on point, all quads, with no overlapping verts or anything :(

I think you had a hidden Object, if not can you provide the blend file?

OMG hahahahaha!!! I figured this out and now that I did i was going back to comment on my own question and already found someone who knew the answer


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How to preset Blender shaders and textures?
In Blender, versions 2.79 and before default to the diffuse shader. In versions 2.80+, they default to Principled BSDF.
Even though this is a nice shader, is there a way that I can actually preset the shader Blender presets to when opening?
Same for textures: Is there a way that when I open Blender, I can have a preset texture?

This is actually quite easy to do:
You can set up the .blend file that Blender default opens.
If I wanted to set up default shaders, I would simply go to the shaders tab, and select the shader I want to be the preset.
Same goes for the textures: go to the textures tab, and select the default Blender texture I would want to be the preset.
Now comes the magical part:
1) Save the .blend as (default.blend) or whatever.
2) Press CTRL+U to give you the "save startup file?" menu, and select it, or for the python-lovers' sake:
bpy.ops.wm.save_homefile().
3) Re-open Blender, and discover the new changes you have made.
This is how to preset default settings in Blender (not modifiers or unset simulators), and I hope it helps all that read this post!

It looks simple but it isn't! If you try to create a new material, you'll still get the principled node as default. It's hardwired in the source code.

You're right, but it is always good for other things. I.e. Starting with cycles default renderer.

But still not the correct answer to this question.. A solution would be to add a new material.new2 operator to startup/bl_operators, and change the all the original material.new calls to this new operator. It's not that easy, but doable.


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How to create a laser beam in Blender?
I am modeling a laser beam in blender, and I was wondering exactly how to achieve the "beam" look of the laser.
I don't exactly want to use a bright red lamp, or an emission shader, because obviously laser dots don't really change in size as you increase the distance between it and the producer.
Here is an reference image of a beam similar to what I am trying to achieve:

There are a couple questions similar to this one, but they obviously do not give information about achieving the volume of the laser, or the bright "star" at the end.
A detailed node setup for a type of projection like this would be the correct solution to this question.
Part of the problem: When I tried the laser lamp node setup for my lamp, it had no effect except for color.
Here is a picture of the lazer lamp's node setup with the model of the lazer case in material view:

This is in rendered view with a volume cube surrounding everything. (Lamp is still selected):
This is my model of the laser case:

Here is the .blend if you want to work with it:

https://blender.stackexchange.com/questions/1096/making-a-laser-in-cycles-straight-beam-of-light   https://blender.stackexchange.com/questions/53548/using-nodes-for-laser-line?r=SearchResults&s=9|44.0767  and also https://en.wikipedia.org/wiki/Lazer

How do I achieve the star at the end? A detailed node setup for this?

I modeled the lazer projector case, and assigned materials to it. I also added the lazer shaders to the lazer projector itself, the ones shown in one of the other questions about lazers.

Just for reference, this is NOT A DUPLICATE. The other question associated with this one has to do with making the lazer dot, not the beam. I am looking to make the beam. I would be happy if you would re-open this question, as it may help future users of this site. Thank you!

Please read https://en.wikipedia.org/wiki/Lazer


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How to apply thickness XYZ to this spiral not a
I have used the screw modifier to create a spiral, but after finishing and applying the modifier, I realize that I did something, and now my spiral is only a line. There was a question recently closed that sounds like this, but I am asking if there is a way to apply something like a lattice to it to make a 3D mesh from it. This is what I am trying to fix:
File here:

Hello :). Why not just convert it to a curve and apply a bevel?

When I tried that it disappeared.

Weird. Works fine for me, just tried it. If all else fails, you can share your file and I'll try to replicate it.

I am not sure if this would work, but my brain tells me you could just:

Select all the vertices
Extrude along y, type in small number (like .01 or however thick you want), press enter
Extrude & scale along shift+y, type in another small number, press enter
Extrude along y, type in same small number but negative
Extrude  & scale along shift+y, type in same small number but negative
Remove doubles

If it works I can post as answer, or if you would be willing to upload blend file that'd be great ;)

Why was this question closed? It has nothing to do with the other one.

The other question answers increasing the thickness of a curve, I can't convert my object to a curve.

Sorry that your question got closed... I checked out your .blend file, I have the solution. Essentially the issue is that you have too many vertices on top of each other. Assuming you are using blender 2.8 or higher (if not use remove doubles), go into edit mode on the spiral, select them all, and then press Alt+M and select distance on the pop-up menu. Type .01 in the Merge Distance field. Now you should be able to convert the mesh into a curve

Could you post this as an answer ?

You can't post answers on a closed question.

I tried the solidify and it worked!! Thank you @cegaton


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Merging two spheres with different radii
I see many posts here on how to merge cubes, but I think my problem is a little more complex.
I'm very new to blender and am trying to create a model of the human lens. The front and rear surfaces have different radii of curvatures. This is no problem and I used to sphere meshes with the correct radii, and then cut them using the bisect tool the model shown here is a reasonably accurate staring point:

I am now trying to merge the two models. Because the spheres are not bisected along their equator, you can see that both "halves" end with a sharp edge. In the human lens there is, of course no such sharp demarcation between the two parts of the lens - it is a smooth curve.
That is my question - how do I smoothly merge the two parts of the lens model while making it look "organic"?

The way you cut your spheres will leve you with very poor topology and uneven border to bridge together. You'd probably have a lot more success cutting along the perpendicular direction, or using revolution surfaces instead with a screw modifier.

See https://blender.stackexchange.com/questions/79697/connect-two-walls-with-a-curve and https://blender.stackexchange.com/questions/66733/how-would-i-smooth-a-90-degree-pipe-angle/

Thank you. I've accepted the answer below but will definitely need to look at the bridging method you link to.

Bridging two sections with  a different number of vertices will yield untidy topology ... perhaps an approach like this would be more flexible?

Start with some sort of sphere for the lens (here I've used a rounded cube). It helps to set its display property to X-Ray.
Create 2 vertex groups in the lens: one of all the vertices above the equator ('top'), and one of all the vertices below the equator('bottom').
Create 2 high-resolution spheres 'top' (the lower one in the illustration) and 'bottom' (the higher one) to represent the curvatures of your lens. (It helps to set their maximum display to 'wire')
Assign 2 Shrink-Wrap modifiers to the lens. One is set to affect the 'top' vertex group with the target sphere set to 'top'.. the other, vice-versa. Perhaps pop in a Subdivision Surface modifier at the bottom of the stack.
Uniformly scale your target spheres and move them along Z until you are happy.

Variations might include leaving a wider unaffected margin between the vertex groups, and/or scaling that margin in XY to get the transition you'd like between the spherical sections.

Excellent, thank you. I have a lot to learn!

Definitely look at Duarte's way using revolution surfaces - this way is a bit tricksy, and just happens to work here.


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Adding A Face / Faces between two objects
I have a Hemisphere inside another hemisphere as per the picture below:
I am extremely new to blender, but would like to create a face between the outer and inner hemispheres. I have selected all the vertices around the "cut" on both the inner and outer object and then used "create face" and was hoping to end up with essentially a solid object with a "scoop" taken out of it - kind of like if someone scooped the yoke out of a hard-boiled egg. Instead, a face was created across the entire surface - so that the inner hemisphere was completely hidden. I was also hoping this would work because each shape has the same number of vertices around the edges I wish to join (the smaller hemisphere was simply copied and rescaled from the larger one).
How might I achieve this goal of ending up with a single solid-looking object? Many thanks for any ideas.

A single face cannot have "holes" in it. You can create two faces instead. For example

Perfect - thank you for helping me take my initial steps with this. I've learned a general rule that's bound to become part of what I do in the future!


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How could I create a 3 Dimensional scribble or doodle?
I am trying to create a scribble drawing but make it spherical as if the pencil or pen lines are twisted within. I have tried to extrude planes and uv map a texture to those planes and unfortunately I lose dimension when planes are parallel to the camera view.

Any thoughts to approach this would be appreciated.

You might try using a curve object

I wrote a small plugin (not addon.. so this must be run from the text editor and it will add itself to the 3d view) -- https://gist.github.com/zeffii/9497c16760f36ed52d15 -- this auto rotates the 3d view to help with the grease pencil drawing -- unfortunately it's not continuous ..working on that...

There are a couple ways you could go about this.
Curve object

Add a curve object (I used a path, ⇧ ShiftA> Curve > Path)

In edit mode (↹ Tab), extrude a vertex around randomly (⎈ Ctrl LMB is a fast way to extrude a vertex many times)

Use the Randomize operator in edit mode to further increase randomness (Space> Randomize)

Grease Pencil

Enable Continuous Draw in 3D view > Tool Shelf > Grease Pencil and press Draw to start drawing

Draw scribbles while rotating the view at intervals

Once you are satisfied with your scribble, convert it to a curve object with the Convert button in the tool shelf:

After adding a curve you'll have to give it some thickness (otherwise you won't be able to see its shadow). See how to do it here: http://blender.stackexchange.com/questions/22932/how-to-add-thickness-to-a-curve (check out a pink vertex's answer).

Thank You! I was thinking of extruding along a path may do the trick then adding some material and texture to rough it up.

Rough render and post effects from instagram http://tomstuder.tumblr.com/post/126561215317/scribble-blender3d

@tomstuder nice result. Looks like a charcoal sketch a bit. How you achieved this interesting texture?

Here is the blend file - https://www.dropbox.com/s/qmk3r0xpmxgpcev/scribble_revised.blend?dl=0

Here is the refined sketch

Use a long strand of hair with 2 or 3 children, then use one of the styling options to randomise them, ie curl, braids etc


text:
Import python modules
I am running Blender 2.49 with Python27 (for testing) and am trying to import webbrowser and os. When I try webbrowser the console returns "no module named webbrowser" when I try os it returns "no module named genericpath". This is extremely annoying as I've looked at various forums on how to do things such as adding the module to Blenders script path and what not, but nothing has worked. I would greatly appreciate any help.
Thanks,
Alex

why are you using 2.49? UNless you have a good reason to use 2.49 you should be using 2.7. There is a huge difference between the two.

As for testing, I don't think you will find more than ten people that still have 2.49 installed and none of them would use it very often. Python scripting in 2.49 and 2.6x is not compatible so you don't need to test any new scripts in 2.49. I would say 2.63 being the first version with bmesh would be the extreme oldest version to test any scripts with and depending on what your script does you may have trouble getting it to work an a version that old.

Okay thanks for the answers and i understand why using new versions is important. The problem is that I want to make 3d printing calculator with php. But to get the dimensions of the objects im passing them through blender and running a script that is out dated and doesn't work with newer versions of blender.

There are a lot of useful tools in recent Blender versions to measure and prepare for 3d printing: http://wiki.blender.org/index.php/Dev:Ref/Release_Notes/2.67/Print_Tools

Wow that looks great! Thanks for the link, I'll see if I can just incorporate those tools with the new version then.


text:
command-line export data to php
I need to open an STL file with Blender, run a script that finds it's dimensions and send them to a php page. All of this should essentially be done through command line or a python script.
So far I've been using cmd with this command:
blender -b C:\blenderTesting\test.blend -o C:\blenderTesting\ -P C:\blenderTesting\test.py

blender -b C:\blenderTesting\test.blend opens the file in blender
-o C:\blenderTesting\ sets the folder for the file to be saved to when finished
-P C:\blenderTesting\test.py runs the python script that finds the dimensions of the object
When I use the above command cmd returns, Error executing Python script from command-line: C:\blenderTesting\test.py (at line 231).
This is the end of the python script
def write(filename):
    outputFile = open(filename, "w")
    outputFile.write(String);
    outputFile.close()

This is line 231 of test.py
Blender.Window.FileSelector(write, "Export")

I'm assuming the problem is that since I'm running this script via Blender background mode it can't open the export window in Blender. I don't want to do this anyway, since I want the script to automatically save the data in a php file. So is there a way to change the ending (line 231) of the python script to automatically save the data without using the export window?
If not, could I accomplish this another way?
Thanks for the help!

Uhm, could be I don´t get your problem, but calling write directly in your script doesn´t work for you?

if I open blender with the GUI and manually run the script that finds the data, and manually save it then it works fine.

Calling your write(filename) should also work in background mode. What errors do you get when trying this?

This is nice but I need to make it automatic, so I run it through the command-line. The problem is with the "Blender.Window.FileSelector(write, "Export")" line. I think this is because blender can't open the Blender.Window.FileSelector since it's being run in the command-line.

I know you want to do this automatically. Instead of calling Blender.Window.FileSelector.. just call write.

okay, I tried "write(C:\blenderTesting\test.php);"

but it came up with an error pointing to the : in (C:\blenderTesting\test.php)

filename should be enclosed in ""

ah just added parenthesis, write("C:\blenderTesting\test.php"); but know its returning invalid mode ('w') or filename on the line "outputFile = open(filename, "w")"

try "c:\blenderTesting\test.php" or "c:/blenderTesting/test.php"

That did the trick! Thanks a lot for all the help.

You could run Blender through PHP, pass arguments (see here) and let Blender print JSON-encoded data wrapped by some text markers. Extract and parse the JSON-data with PHP and use it.
Example implementation:
https://github.com/CoDEmanX/blend_stats
Note that Blender.Window.FileSelector(...) is only valid in Blender 2.4x, API is completely different in 2.5x / 2.6x.


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transparent background for volumetric smoke? Bug?
I'm trying to use transparent background in a simple smoke simulation.
As soon as I check transparent, in the film settings (cycle), the image loose the color (it is indeed transparent but black).
I've a simple volume shader and just a white background
EDIT: as requested here is the blend with a quick smoke with default settings, nothing specific.

I've seen this closed bug and this question maybe the bug is still there?
Anyone can confirm this behavior and have a workaround with the compositor?
Because simply mixing the black transparent png with the color doesn't produce the same result

Can you upload your .blend file? I'm also puzzled.

I'd help but the smoke domain is a complete black box. :/

As far as I'm aware this bug is not/never has been fixed. Note that the report was closed as "archived", rather than "fixed".

Thanks gandalf I've missed that important detail! Maybe the issue has changed since then, because in the other thread the proposed solution shows a colored render instead of black. I'm looking for a way to uniformly color the current black transparent output restoring the color it has when rendered with a white environment color. The current tones of grays seems correct it just seems to be missing the color and I can't find a way to add it in the compositor!

Short answer: You want to use the volume scatter shader for this, not absorption. (or use the post-pro workaround in the other answer).
Ok, let's back up a bit and I'll try to explain why Cycles produces the values it does with the absorption shader: First of all, the volume absorption shader does not add energy to the ray or add contributions for a light in any way, it can only remove them. This is because absorption does not alter a ray's path, it merely removes energy from it. With transparent film, it's subtracting from the already black background, thus leaving you with a black smoke plume. "But wait!" you're probably saying, "my background isn't black, it's white!"
Oh boy. What a fun can of worms we got into here. So when you're rendering with a transparent background, you need to make the RGBA color of the background black. The reason for this is how the alpha over operation (or "normal" blend mode in Photoshop parlance) works. You can read the formula here: https://en.wikipedia.org/wiki/Alpha_compositing If you look closely, you can see what it does is multiply one layer by the alpha (blacking out the transparent portions) and multiply the other by the inverse of the alpha (blacking out opaque portions) then sums the results. So the function of the alpha channel in this case is to tell the software what part of the existing background to remove to allow the new background to be added.
This works just fine for 100% transparent sections no matter what else you mess up along the way (like writing the RGB channels as non-zero). It's partially transparent areas where the problems start. The non-zero RGB values in the background represent incoming energy from the background, which you do not actually want. You're providing different energy values later by way of comping in your final backplate. When you have a partially transparent region though, you want to preserve some energy (the energy reflected by the occluding object), so rays returning the value of the occluding object have non-zero RGB and an alpha value of 1. (ok, they might have RGB=0 if the occluder is black, but let's just assume it's not). Rays that continue to the background have an alpha of 0, thus the average alpha provides the proper scaling factor so the right amount of composited backplate energy is left on the pixels.
But what if those backplate rays came back with a non-zero RGB? The alpha channel does not distinguish between colors from the occluded object and colors from the backplate, it just represents how much energy is supposed to pass through the occluder. Thus, you get an unnatural glow as you are stacking the energy of the render background and final composited backplate, where this wasn't supposed to happen. Oh yeah, and because of antialiasing all objects get a partially transparent region around their edges, so even opaque objects get a halo if you don't black out this background.
And all this glowy mess isn't fixable in post either, at least using just the main beauty pass. If you have an occluded environment AOV (like cycles' environment pass) you can subtract that from the beauty pass and straighten things out, but no messing with a "convert premultiplied" switch will do the job.
This is all fairly arcane, so to make it easier on the user when you enable transparent film Cycles just stops all camera-ray contributions of the world background, forcing it to return RGB=0 in all cases. Your volume absorption shader tries to remove energy (especially red and blue energy) from a ray that has no energy to begin with, thus your smoke is black. Using the scatter shader instead causes it to REFLECT green light, thus remaining visible on its own. If you'd rather have the glowy green look, you can also specify that directly using the emission shader instead of, or in addition to, the absorption shader.

Thanks for your explanation of why this problem shows up! Unfortunately I understand better the problem and I see there is no easy solution, however I can't replicate your proposed solutions. Subtracting AOV  (as shown by @cegaton below) leaves trace of the white environment light as you can see here. I know Volume scatter works but the results looks very different! Plugging directly the emission (with density>strength)  in the volume socket I got nothing. Using it with an add socket works but the results are different. Any better setup?

It's kind of a tricky problem, because a single RGBA image does not store enough information to get the result you want (filtering the background image) with an arbitrary background. Alpha becomes the average attenuation, but the color comes from the green attenuation being weaker than the red and blue. I think emission+absorption (add shader) or putting the color back in post are your best bets.

As an workaround I would use compositor as @Rick Riggs suggest, but in a very different way:

Render the smoke over some color that is not included in the smoke and then key it out in external app compositor that keys transparent gradients/transitions well.
If the smoke is lit or emission based render the smoke over black background and using this trick turn that black background into transparent.

This is a very neat trick but how can I apply here? If I put any background it'll alter the light of the volume absorption, this is not an emission shader.

@diramazioni Yes this is true. If you have a thin smoke that get's effected by the background emission and it's an issue then the only option is that black background.

The black background will make the smoke vanish completely being 0 the light the volume absorption shader is able to absorb! Do you imply some other trick with ray visibility cycle property? I've tried but wasn't able to make it work in any way. Maybe using an emission shader with add in the volume socket is the way to go? Do you have a working example of your idea?

@diramazioni If you have black smoke render it on white like you have the image with green smoke, then invert, make the black transparent, then invert back. Yes I have a working example, our entire studio smoke pipeline is based in this transparent channels pipeline. I'll apply it to the file you provided.

@diramazioni I see what the problem is now, I will use a bit different setup to solve it and will edit my answer.

@diramazioni I have bad news. The correct setup works in CMYK color space and makes white transparent. I am unable to reproduce it in Blender:(

No problem! thanks for trying anyway and pointing to that neat hack I didn't know. If your studio use transparent smoke how is your setup? Do you use volume scatter? Maybe it's just for print since CMYK. just curious

@diramazioni we run these: http://www.howtogeek.com/59634/remove-backgrounds-automatically-with-a-free-photoshop-action/ and similar postproduction effects in compositor software. If Blender could do the CMYK white extraction that would be it.

I think your best bet for now, is to use your Black and White version, and run it through the compositor like so to get your color back.

What if the smoke is multi-colored from lighting for example? This setup is just coloring it with single color and in a weird manner. The correct thing is to render the smoke over some color that is not included in the smoke and then key it.

Rick I've tried your setup and I wonder how you got this result, and the rationale behind it because I can't replicate. From the screenshot I can't see the value of multiply, but beside the numbers why a multiply operation of a black image over black would produce any result? Can you provide an example file because frankly I'm a bit puzzled, The result looks good, but I hope you haven't started by using the png posted here with the non transparent white background, I can't figure out otherwise why of this node setup

I did start with your png greyscale over white.

As far as the multiply object goes, notice how the first multiplier is acting as an intensity control on the mix factor by value. The next item is an invert not a black image, so in other words if i am to take the source image's greyscale and invert it then I get its b&w opposites (hope that clarifies that). Now because I am also making the invert of the source image as the alpha channel, all that is left is the multiply of the source left overs and your color of choice.

As for the multiply number specifically, I would say start at 160, and slide up or down until you like it.

Oh no! You should have read more carefully. The output it's a transparent b/w image as you can try your self with the provided blend or any smoke simulation with just a volume absorption as material and film-transparent setting. The white background of the uploaded png I think it's added my the image service here at stackexchange because I've uploaded a transparent one!

You should be able to basically render out the alpha pass and plug that into this solution.


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Why is my alpha pass binary (just 0's and 1's) in Cycles?
In Blender Render, my rendered alpha pass has intermediate values (e.g., 0.83) at the boundary -- great for anti-aliasing compositing!

However, when I switch to Cycles, my alpha channel is always binary, i.e., consisting of only 0's and 1's.

For some other reasons, I have to stick with Cycles. How would I produce an alpha pass with intermediate values in Cycles?

@wizzwizz4 Monochrome is single chroma, single hue in colorspace. The term Binary image is correct here. Binary is subset of Grayscale and that is subset of Monochrome.

@wizzwizz4 Since there is an image showing what it is and there is even explanation in brackets in the title, I fail to see the problem you are trying to solve. At least people will learn what Binary image is. Black&White is used as synonym for Grayscale, it's misleading same as Monochrome was. People not understanding something is normal and does not justify avoiding correct terms, it even might spread confusion. Binary is the best how to call this and there is no problem with it because this is not a casual site, here you will come across many more technical terms.

You have only 1 sample set for Cycles:

Any particular sample in Cycles will return either 1 or 0 for the alpha channel. Antialiased alpha edges are built up by averaging multiple samples, some of which strike the occluding object and some which do not. Using a larger number of samples, such as 16, will fix the issue.

This is cool. But how many samples are enough? Hmmm.

That's one of those nebulous "it's enough samples when it's good enough for you" things. Technically, any sample count greater than 1 gives some antialiasing. The more samples, the more antialiasing. There's no way to say definitively when it's enough. 10-20 is a nice ballpark in a lot of cases, but who knows? Rendering is complicated.

Roughly speaking, ~32 samples will clean up images with only diffuse and no bounce. But usually you'll have much more than that. If you have bounce light, you're looking at ~250 for diffuse to clear up, ~500 for glossy, and anywhere from 1,000-3,000 if you have complex reflections, glass, volumetrics, etc. This can be brought down with certain settings, and the use of the denoiser.


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Planes rendered into two triangles of different colors?
I defined some glossy planes by specifying the four vertices and vertex order for each. I rendered them in Cycles under an outdoor HDRI lighting. Strangely, some of the planes split into two triangles rendered in very different colors.

At first I thought it was due to surface normals, so I made sure the surface normals all point to the camera. However, the problem persists.
Why is it so, and how may I fix this? Many thanks!

Is your mesh smooth shaded? It looks like it is flat shaded ,so non planar quads will inevitably show visible sharp edge. Make your mesh smooth shaded, check Auto Smooth under Mesh Data in the Properties Window or add an Edge Split modifier. You may need to manually mark some edges as Sharp in Edit Mode if you have a mix of Smooth and Flat shaded areas in the same object.

@DuarteFarrajotaRamos Thanks a lot! I just tried enabling Auto Smooth and am having a new (different) problem. I've updated the question. :-D

Try adding an Edge Split Modifier, if that isn't enough try marking smoothness-breaking edges as Sharp under edit mode. If it is still not enough, you may actually need more geometry by subdividing your mesh with a Subsurf modifier, though that will require adding a lot more control loops

@DuarteFarrajotaRamos many thanks again! As a newbie, Edge Splitting and Sharp sound like the opposite to what I want -- they sound like something that breaks the smoothness? Also, I am actually free to add more geometry to subdivide my mesh, and my computation resources allow for that too. In this case, I can just further subdivide my mesh, right? Does subsurf have more advantages than this? Thanks again!

Subsurf is non destructive, so it can be adjusted dynamically

@DuarteFarrajotaRamos Just tried subsurf, but it is weirdly rounding my quad plane. Question updated -- any ideas? Huge thanks!

That is what subsurf does, it rounds things. If you have a mixed round/sharp geometry and don't want something to be rounded you have to add control loops. GO watch some tutorials https://www.youtube.com/watch?v=nBkwodrQq_4 and https://www.youtube.com/watch?v=aQZ5ZAldzu4

@DuarteFarrajotaRamos Thank you Sir! Your comments already solve my original problem. I guess it would be better for me to ask a new question on these followup questions, which I just did. Thanks and happy new year!

For future readers: (TL;DR) This triangle effects can be removed by enabling Auto Smooth under mesh settings.
Credits to @DuarteFarrajotaRamos:

Is your mesh smooth shaded? It looks like it is flat shaded ,so non
  planar quads will inevitably show visible sharp edge. Make your mesh
  smooth shaded, check Auto Smooth under Mesh Data in the Properties
  Window or add an Edge Split modifier. You may need to manually mark
  some edges as Sharp in Edit Mode if you have a mix of Smooth and Flat
  shaded areas in the same object


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Hot to make nonwoven fabric material in Cycles?

Due to complexity I am unable to make this material with shader nodes. Can anybody please advice how to approach this?

I hope you don't mind my edit. If you ask for resources, this will just get closed as off-topic, but someone can help you learn instead. If you find that I changed the meaning of what you wanted to communicate, please edit the question again. It would be helpful if you describe what you have tried as far. What failed?

You could use a Voronoi texture as Bump map, put its Randomness at 0 and rotate it 45°, mix it with a Noise to have some nuance, also plug a Noise into the Base Color of the Principled BSDF to have a grainy color:

File:

plz share file.

@atek, sure check my answer


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What would be the best way to hollow out the space for nostrils while modelling a head?

I finally got the skull where it should be more or less. Is it possible to add in some nostrils? What would be the best way to hollow out the space? Thanks.

There are many ways to do this. One way would be to just inset some faces and then extrude them towards inside.

You will probably want to edit the topology of your model using another modelling tools later to add more detail to the forms. That's why I would recommend watching some video tutorials about modelling.

Thanks Martin. I haven't checked out any tutorials yet what are those. I'm not sure how I really learned this. Sometimes I just want a visual as you provide.

Well, if that works for you, then it's great. It's just that I think it might be easier to get yourself familiar with these things watching videos, because usually a lot of functions are explained together and they demonstrate ways to use them. If you look for Blender modeling tutorials on YouTube I am sure you will find a lot to chose from. People will try to answer all the questions here, that's fine if that works for you, I just think it might be faster with videos. I don't know, I guess whatever works... It seems you are on the right track.

Thanks Martin. How do I search for them are they on YT? This stuff comes easy at for me at funfundachtzig, I thought tutorials just for millenials. :-) Thanks very much for informing me.


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how to efficiently build a rippled roof?
I'm currently trying to reproduce this in Blender:

However, I'm not sure how to proceed with the roof and it's "ripples". I haven't found a proper texture yet and testing with other metal textures doesn't give me the feeling I wanted.
Making many loop cuts might give me a feel but it's also very performance-consuming. Another option could be using a wave texture but I wonder if this is the best solution. What do you guys think?

Hi, Christian. I edited your question and put the picture directly into it so it follows the guidelines of the platform a bit better. Hopefully it will make it easier for the people who might attempt to answer. Hope you don't mind. Also, the picture does not show the roof very clearly. It's a bit hard to see how it is made so this might be an obstacle for solving the problem. Do you maybe have some more image of what exactly you are after? If not it's definitely a good idea to find some.

Hello Martynas, thanks for your comment. I purposely didn't upload the picture as it wasn't mine and I wasn't sure about copyright. What I'd like to achieve is to have an iron roof that comes close to look like that: Link

@MartynasŽiemys: now you are just one step away from prison... :D

You could use an Array modifier to repeat the same pattern, have you tried? If it's not for close-up shots you could also bake the normals

You can loop cut a plane several times, select every other edge and move up on the Z axis.

Then Shade Smooth and select all the short edges and Ctrl + B Bevel to the desired depth.

Or just apply a Wave Texture as Bump data for the texture (mind the Distance value).


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How to use an opacity mask in a material in Blender Cycles?
Following a tutorial about creating a stylised tree, I ran into a problem. The tutorial is for Maya instead of Blender and Substance Designer. I modelled on Blender.
In the tutorial for Maya they manage to insert the basic color map and the opacity mask well, which I can't do in Blender. I have attached images with the problem. I tried to search on the net but I can't achieve showing only the leaves and the branches as it happens in the tutorial.

there are some wrong inputs in your image
basic mask setup in blender:

I did it anyway but thanks for the help. does it involve anything to invert transparent nodes and base color?

there is a color invert node in the color tab

I solved, sorry for the trouble. I fiddled a bit though, I solved it with a lot of luck xD


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How can I align a model to three custom points with a Python script?
I want to align the axis of a model to three points with a Python script.
How do I do this?
I pick three points that form a triangle with a right angle
like this:

I made point A the origin (0,0,0).
Then I think I should rotate the model around the point A
so that AB and AC are aligned to the axis, but I'm not sure how I can do this.
Should I get each vector's angle that separated x,y,z?
Or is there any option in Blender to use for this?

Create the matrix world
The rotation part of an objects world matrix is an orthogonal matrix where the columns represent the local axes.
To demonstrate, in test code below,  I have added a plane and removed one vertex to visualize the  three points A, B and C ensuring the angle between  BA and CA is 90 degrees.

Cube (orange wireframe) aligned to 3 vertex, 2 edge "plane" Vertex 0 for B, 1 for A and 2 for C
The vectors BA and CA, normalized,,  are used for the x and y axis directions.
The cross product of x and y is the z axis.  (The negated value would be the "flipped" option)
Finally build the matrix world from the 3 axis vectors, make it 4x4 and the translation A.
Test script. Move and rotate the "plane" then run script to align "Cube" such that its origin is at A, and the x and y axis align.
import bpy
from mathutils import Matrix
context = bpy.context

scene = context.scene
tri = scene.objects.get("Plane")
# global coords of 3 verts in plane.
b, a, c = [tri.matrix_world @ v.co for v in tri.data.vertices]

x = (b - a).normalized()
y = (c - a).normalized()
z = x.cross(y)

M = Matrix([x, y, z]).transposed().to_4x4()
M.translation = a

# Cube is the test object

ob = scene.objects.get("Cube")
ob.matrix_world = M

Note I have used blender 2.8. Replace matrix - vector multiplication @ with * for prior versions.

You can use Damped Track constraints.

Add two damped Track constraints.
Choose an object (B, C) and an axis, that should point towards the object (Z, Y). Then enter them as the Target and the To in the constraint settings respectively.


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Why is Solidify modifier producing results I did not expect?
Solidify modifier is not working the way I expected. I have a simple extruded mesh and I want to give it a solid thickness with Solidify modifier. When the modifier is added it does not produce a perfect even mesh at the edges.

How can I give a solid thickness to my mesh?

Firstly, when you have sides that move outwards, they will not align well. Secondly, The solidify tool is not made to fill in thick walls perfectly. it is mostly used for adding thickness to glass and other thin sheets. I recommend using the extrude tool and manually moving different faces around. What I did was extruded the whole wall away from the main face. I then grabbed any overhangs and pulled them upwards/downwards as required.

as said by Bigfoot, when you try a negative value, it will work better. Also try to enable the Even Thickness and High Quality Normals options. And if it's still not good, as said by Bigfoot, give thickness with extrusions and work with the vertices


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Texture painting appears on wrong faces or not appearing at all
Painting appears wrongly in Material Preview and Rendered mode. It appears correctly only in Solid display mode.  Faces are in correct orientation, recalculated normals and outside too. Applied all transforms.  Tried removing and adding materials and UVMap. Still the same. First it was painted wrongly but after many attempts to correct this behavior I ended up with no texture drawing in material preview and rendered modes at all... By the way I am making this donut independently and In my second file which I did following the Donut Tutorial everything works fine.

File with texture painting issues

...and this is the one following the tutorial

In the shader editor, the image texture input is linked to the "generated" coordinates.
Plug it to "uv" or remove it (as "uv" is the default).

Without uv, Blender cannot write/map to the texture correctly.

Thank you! This has finally solved my problem.


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My Character is Destroyed when I Move any Bone

When I've finished my character mesh and I parent it to my bones, it makes it stretch when I move any bone.
All the mesh have effect and moving Random.
this link for my blender file:
https://drive.google.com/file/d/11BLVjRA3f0ixPRzBzymJMkamyy8-tEDw/view?usp=sharing

try subdividing the mesh I think that should help

I did it maram but nothing happen thanks for try

As you see your face normals are flipped, you need to recalculate (select all in Edit mode and ShiftN):

Also your feet are tweaking because of their Pole Target, I'm not sure what you are trying to do there but try a rotation of the feet bone in Edit mode: CtrlR-90 for the left foot and +90° for the right bone.

Thanks for that help, you take images and explain very well, ☺ man wtf this success and very useful bro i cant say anything but you helped me omfg thanks for you sir!!!!

thanks for you sir i will ask God for let you get in the right way and success in your life!! you dont know how much i waste for try to fix it ;)

how do i can support you sir ?? i will do anything for say thanks

@Rami Alyazje you're welcome   ;)


text:
Cloth not falling
I have just been following this tutorial of how to make simple clothes (the jacket) which should involve sewing
https://www.youtube.com/watch?v=W9GDWKzf1mc&t=758s
I followed all the rules as best as I could but at about 12:30 where he hits space bar to make it fall, my cloth did not fall...
I have checked some other questions and tried to apply some fixes that were suggested.
My problem is that when I hit space bar, the cloth will not fall after I tick 'cloth' I have also checked that gravity is at 1.0000 and that all eyes or on. Does anyone have any idea what I am doing wrong?

I am trying to upload my .blend file for this project. Please just comment back to me to let me know if it hasn't worked instead of closing my question. I'm trying to learn!

Does this answer your question? Cloth simulation doesn't work for particular object

Scale the sleeves on Z so that they cover the arms enough, apply the Mirror modifier, recalculate the normals, merge by distance (the overlapping vertices seem to be the original problem here), increase the collisions Quality, it should work better.


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How to Fix Masking for Separate RGB Node
Newbie here, I'm trying to follow a tutorial and encounter below problem.
I am unable to mask properly. If you see the SEPARATE RGB gives a gray output in G for the stem.
Whenever I try to mask the stem, it mixes up with others.

First, I have set up the TOP and the RIDGES using 'SEPARATE R' as the influence factor for Mix Shader . It gave me below:

Using the 'Separate B' as influence factor for the Mix Shader and just rearranging the connections. But the RIDGES are visible when using this, so I have used 'SEPARATE R' to move forward.

Now, when I attempted to mask the STEM of the mushroom using 'SEPARATE G', I am unable to do it correctly. The STEM texture mixes up with the other texture that it made it not visible.

Since the SEPARATE RGB have calculated different shades of black, I am having issue on masking. How can I fix the masking using SEPARATE RGB? Or what is the better approach here?
This is the paint image that I have done:

Here is the file:

your mask is full black in the file attached here. You should paint it (appropriately to the uv map) in either r, g or b for each part of the uv map.

Apologies for that @lemon , Im trying but I am unable to attach it to the .blend file.

I try an answer, but it could be wrong without this mask texture... tell me...

Yes I have included the image in the main post.

The TOP = [1.000000, 0.014897, 0.020143, 1.000000]
The RIDGES = [0.014239, 0.004859, 1.000000, 1.000000]
The STEM = [0.522476, 0.118687, 0.016875, 1.000000]

If top (orange part?) is a mix of full red and partially green and blue, the result should be a mix. Is that what you want?

Yes.
In the tutorial, the lecturer have used mostly S= 1 V= 1 and then the Hue he selected different colors.
I'm not sure if I should use only colors that is following that order when I need to do MASKING.
So I went and just pick a color having different combination on HSV

A close up on the mix shader nodes:

The first one on the left:

If red, this is top
Else, this is ridge

The second one, on the right:

If green, this is stem
Else, this is either top or ridge (depending on the previous mix shader)

So you need:

Red for top
Green for stem
Other (blue, or eventually, simply black) for ridge

Thank you for this @lemon.
Somehow I now understand that I can only use Red, Blue and Green in the image paint to dictate the masking.
What I was doing before is to copy whatever color I gave in the ColorRamp, and use the same in the image paint.