Troubleshooting Boolean Issues Blender 2.90.1
I'm relatively new to blender, only have been using it and following tutorials for a couple months. Typically, with enough research I can solve whatever issue or mistake I come across, but countless google searches and this one still eludes me.
Currently I am following Derek Elliot's phone product animation video where he begins modeling a phone, adds a couple bevels and a solidify modifier for the body, then duplicates it retaining the modifiers (excluding the 2nd bevel) to create the port and buttons on the outer edge of the phone before applying a boolean to those intersecting buttons so that they cut out shapes from the phone body.
When I initially followed this method, my phone became "hollow" with the 'eyedropped' shapes just becoming transparent when set to bounds. (or wire.) I dug through the comments for tips but found nothing, moved to google and forum searching where there were similar problems, but none that solved mine. (manifold problems etc.)
I began to just try some trial and error within blender and have discovered:

Default cube resized functions (mostly) properly with a boolean.
Duplicated phone mesh with phone modifiers (tutorial video) did not work regardless of placement.
Separately modeled port shape works only when intersecting the top face of the phone.
Modeling the phone at both life size scale and fictional large scale produced the same problems.

Issue seems to come from straying too far from a default mesh. Too many vertices?

I had a similar problem and am in a similar situation to you (in that I'm relatively new). I believe the solution ended up being checking where I shade smooth and manually changing the geometry so I didn't get any weird artifacts. If I remember correctly, the issue is with the two meshes having different geometry, so blender struggles to match them in a pleasing way.
Hope this helps


How to control bevel in a curve? I trying to make a rib that follows the edges of the column, but it doesn't work the way I wanted it. How am I supposed to know how much I need to turn the bevel object to get the desired effect? I don't wanna change the location or rotate the curve because it would be later hard to fit it perfectly into the vault. Or maybe there is a different way to do it?

For a Bevel-Object swept along  a curve-path, the rules are:

The Bevel Object will be projected down its own positive  Z axis.. its own positive Z is 'Front', as it travels down the path.
It doesn't matter where the path's object-origin is.
It doesn't matter where the the Bevel-Object is in the world. Its object-origin will lie on the path, when projected, (assuming no Offset in the path's Data > Extrude panel).
'Up', with respect to the path's normals, will be the Bevel-Object's own positive Y axis
'Right', looking down the path's direction, will be the Bevel-Object's own positive X axis.

This is quite hard to illustrate clearly. I suggest moving the profile-curve to somewhere it's convenient to work with, maybe the World origin, and switching on the display of the path's normals in its Edit Mode, in the Overlays dropdown.
First check that the path's normals are left-to right, at right-angles to your desired 'Up'. Setting its Twist Method to 'Minimum' in its Data > Shape panel should do that.
Then rotate the profile in Edit mode, so it's flat in XY, and its top is pointing down its own positive Y axis. In the profile's Object > Viewport Display panel, you can switch on 'Axis', as above, to reassure yourself of the alignment.


Importing SVG images to Blender I'm having trouble with imported images in Blender, they don't respond the same way as the native images on Blender do. I save .svg files with Illustrator and it is vector art. I'm just trying to get an embossed look on these images.

I think you will run into problems with such complex paths/curves. Extrude might work but I think beveling wont work well.

For an embossed look I would use the image as a bump map/texture/heigh map:

Add a plane in blender, UV-unwrap it and add your image as a bump map. You should unsharpen your image for a smooth beveling effect.

You could even mix differently smoothed images together for a more distinct look.


Cut edges in the UV Editor I have an UVMap and I try to editing that. As we can see below there are couple of faces which are not placed very well.

So I would like to separate those faces in order to place them from here:

To here:

But I can't find the solution to cut edges to separate faces in the UV Editor.

1: In the UV/image Editor select the vertices/faces thet need to be moved and use the Keyboard shortcut key Y to separate them.

2: Move them to their new position.

3 To join them back to the UV's...... select each pair of vertices to be joined then open the Weld/Align menu with the W key and choose Weld.


View image without any interface Is there a way to view JUST the rendered image while making the interface disappear (a la Photoshop fullscreen)?  I want to see literally only my rendered pixels and zero Blender interface things.  Thanks!

actually the whole interface can be removed from ANY view, not only the Image Editor. Place your mouse cursor over the area in question, then hit Right Alt+F10 (maximize view and remove interface) and then Alt+F11 (remove title bar and also task bar on Windows or dash on Linux). To get back, you can use the same keystrokes, or move the mouse cursor in the top right corner of the window, until an icon appears.


Values to straighten wave texture? I am using the wave texture and am faced with a dilemma: by default, it is rotated in some obscure way. I want the bands of the texture to be aligned with each axis (x, y z) but cannot for the life of me figure out the rotation values required to do so. Any help?

It is probably just easier to recreate it using math nodes rather than trying to align it to axis.

Use a Math Node set to Cosine; as input use your desired texture coordinates like Object or Generated.

Add a Separate XYZ node and use the desired axis as direction, then multiply it by any value to control density of the waves.

You can still run the output through a color ramp node to control progression and color, and covert the whole thing into a node group for simplicity sake, to make it visually cleaner, easier to reuse or port to other files.


Is it possible to get a camera solve of large camera dolly? I shot this footage of the beach from inside my car and i am trying to 3D track it and get some camera solve but blender doesn't seem to recognize the movement at all. I alway get huge solve erros and the camera doesent seen to move at all inside 3D viewport.
The Footage:
https://www.youtube.com/watch?v=-F5k8WtR528

Yes you can track a shot like that, as long as you decide to put some effort into it.
The shot has enough information to create 3d information, as it clearly shows parallax. You should be able to get a pretty accurate reconstruction out of it.
The most important part is that you track the island in the far background (and maybe some clouds that show enough contrast on the edges),  then parts of the middle ground (the metal bars on the beach) and close elements on the street. The elements that are in the foreground close to the camera are going to be the hardest elements to track, since they move too fast, so you will need large search boxes for the tracker. You will need to track a lot of different points in the street, that come in and out of the frame.
Place your trackers manually, don't rely on the autodetect features of blender. You shouldn't track moving elements like the waves.
3d reconstruction works by estimating the placement of points in the 3d world by computing the changes of the objects on the images. Objects that are close to the camera move faster than those far away. Computing the difference in speed, blender can determine if objects are close or far, and where the camera is with respect to the objects.
Blender's 3d tracking capabilities are quite sophisticated, but you need to understand how to make them work for you. The most important aspect is that tracking is done as accurate as possible.
You will need to babysit the trackers and make sure they are not slipping or tracking unwanted features.
The most challenging  aspect of this shot are the elements that are occluded by passing objects (the bicycle, the palm trees will block the island, etc). Those blocked elements need to be tracked in different segments when the elements are visible, and then have the trackers joined, so that blender understand that it is dealing with the same element. Other elements can be tracked using offset.

confused?
Read very carefully trough the following links (yes, all of the text), all the information you need is there:
How can I get better results when doing camera motion tracking?
and Joining 2D tracking markers with an offset


how to fix this rigging problem I have studied Blender for a while now, and I just started rigging and then this problem occurred:

The main bone is not connected to the main body bone, and I have tried to parent it to the main body bone to no avail.

P.S: This is my first post on this site so I have no clue how things work around here so forgive me if there is grammar/mistake in the question I asked, and please note that English is not my first language :D

My first guess would be that you're trying to do parenting in Pose mode. Switch to Edit mode on your armature and you should be able to parent bones without problem.


How can I rotate the rigged child leg with whole body? I'm from Korea. Please be understand my low English skill.
I made a robot and put a bone in it.
All part is connected as child and the body is currently parent status.
If I rotate the body, arms and legs rotate together.

But I want to rotate the whole body with the left leg as the axis.
It's like a ballerino spinning with one foot supported.
However because the leg is child, this is spinning alone.
Please let me know the solution!!
I really appreciate it if you can help me!

You could give your bones a root bone that would be the main parent of your bones (so it would be the parent of the current parent, that is probably the spone bone) and put the foot over this root when you'll want to make your rotation. Or create a bone under the foot and give your current main parent (first spine bone probably) a Child Of constraint that you activate (by keyframing the Influence value) only when you want the rotation to happen:


How do I get the fire to show up for the mantaflow fire and smoke effect in Blender 2.92? after setting up the explosion and smoke on my objects, then baking them, I am not seeing the fire that supposed to be there. The domain is set to gas and the objects are set to fire and smoke. The explosion is working just fine. I tried fixing the shader of the objects that are set to fire and smoke and tendering in both cycles and Evee. Is there something that I am missing?

While I'm hardly an expert at mantaflow explosions in blender, I've also noticed that it's pretty hard to get the flames to show up. From what I can tell, the 'flame color' setting in your Smoke Domain's Physics->Fire->Flame Color settings doesn't seem to have any effect at all.
I have had some luck following the simple instructions in this short video. Basically, you select the smoke domain, go into the shader editor, and increase the blackbody intensity. I suspect this is just one way to get the flames to appear as anything other than black, but it's the simplest I've seen so far.


Is it possible to hide curves' guides in edit mode? In this example I use Nurbs curves to create shoe laces and it becomes quite hard to operate curves in the regions of loops and knots because of the curves' tilt/scale guides (not sure how to call them). I would really like to hide these guides when I edit curves. Is it possible?

Those black lines are the normals for the curve.

Blender 2.79:

You can change the way they are displayed in the "Curve Display" tab.

Blender 2.80

To make them smaller change the normal size.

To make them disappear uncheck the normals box.


Will this help program my 19 button mouse? I have a Left index finger that is fused at the second knuckle , therefore I bought a 19 button mouse to compensate. The box said it has programmable buttons.( Utechsmart Venus).  I'd like to use the 12 side button's for the combination of shift,control,alt and use the keyboard for the other characters.
Will the add-on for programming keys menus and pie help with my endeavor to continue learning blender?

The "Programmable buttons" are usually configured in a system control panel for the device, you should find a place where you can specify what action/key is assigned to each button.

Another approach to try is to open blenders input preferences and adjust an action you want to assign to a button. Where the mouse/key combination is shown, you can click that and the next mouse or keypress will be assigned to the action. Try adjusting an action and pressing one of the mouse buttons to see if blender recognises the button, if not you will need to rely on the system configuration to set each button to emulate keystrokes.

While I am not familiar with the addon you mention, blender is very customisable, you can setup the shortcuts to suit what works for you, modifier keys can be disabled so that menus are displayed with single key presses, using python you can create your own menus - either a vertical list of items or a pie menu.


What is the difference between scene camera and data camera and how to set the FOV? I tried to set the FOV of my camera but could not do it via bpy.context.scene.camera. When I tried to access the angle property I got AttributeError, but I found bpy.data.cameras["Camera"] has an angle attribue that I could change. My script now looks like this:

def setup_camera():
    camera = bpy.context.scene.camera
    camera.scale = (-1, 1, -1)
    camera.rotation_mode = "QUATERNION"
    cam = bpy.data.cameras["Camera"]
    cam.angle_x = 69.4
    cam.angle_y = 42.5

I just wanted to know if this is the right way to change the FOV? I guess one is a camera profile the other one is an actual camera?

I'm not that familiar with the structure of Blender's type hierarchy, but according to the documentation for Blender's Object type there is a distinction between the object and the objects's data block.

# From Blender's Documentation:

# Create new lamp datablock
lamp_data = bpy.data.lamps.new(name="New Lamp", type='POINT')

# Create new object with our lamp datablock
lamp_object = bpy.data.objects.new(name="New Lamp", object_data=lamp_data)

Likewise, bpy.context.scene.camera is a Blender Object type which has its camera specific attributes stored in it's data block of Camera type, which can be accessed with the attribute data.

camera = bpy.context.scene.camera
camera.data.angle_x = math.radians(69.4)  # angle_x and angle_y take radians

The properties panel in the user interface is arranged the same way. Values like location, rotation etc. are set in the Object tab, type specific values like the Field of View of a camera or shape keys for a mesh are set in the Data tab.

You could also have more than one camera in the scene, in which case the cameras could either be accessed as objects in bpy.data.objects['<name>'] (with the camera data accessible from the objects's data attribute again), or you access the data block directly bpy.data.cameras['<name>'].
bpy.context.scene.camera would only refer to the active camera of the scene, just like the corresponding entry in the properties panel under the Scene tab.

N.B.: I assume angle_x and angle_y can't be set independently but instead are coupled by the aspect ratio. If you set angle_x, angle_y will follow suit.


clean up ugly topology I recently found a free Kitbashing kit on gumroad but when i import the .obj file on blender 2.81, all the object are tri or simply unusable like in the example below.
I know that this pack was meant to be used on fusion 369 or 3DSMAX but is it really necessary to use these 2 ?

Do you have an idea why this is made like this ? Is it a importation mistake on my part ?
I've tried to use the blender inbuilt tri to quad but to no effect...
any idea ?

anyway thanks you for your time.

ps: english is not my first language so sorry if some sentence are a bit wonky

link to the orginal pack on gumroad : https://gumroad.com/olegushenok#WagY

Select object in Edit mode, press Ctrl + F > Tris to Quads, and set the Max Face Angle and Max Shape Angle to 179 in the tool options.

Go to Object Data Properties > Geometry Data and click Clear Custom Split Normal Data

And finally, In the same tab, under Normals drop down menu, click Auto Smooth

That should take care of it, hope this helps


Blender CUDA Flatpack OS: Manjaro KDE
GPU: Nvidia GTX 1650
I tried using blender from the official repos, for some reason certain features dint work.
I installed blender from Flatpak, everything works fine exept it does not detect my GPU,
But CUDA worked fine when I used it from official repos,
Does anyone have a fix for this?
I have tried reinstalling, It dint work!

You need to install NVIDIA drivers separately via flatpak to enable GPU rendering.

Run  flatpak list  in console.
Check if you have a package with application id similar to org.freedesktop.Platform.GL.nvidia
If not run  flatpak install org.freedesktop.Platform.GL.nvidia
and install the latest drivers.At the time of writing this the latest driver was org.freedesktop.Platform.GL.nvidia-460-27-04


Knife project tool is looking rough after I extrude on a curved surface Hello Blender Stack Exchange Community!

I'm creating a cuff bracelet and using the knife project tool to "etch" text on the inside of the cuff, but the results are super rough.

The cuff (mesh circle) has a subdivision surface modifier (3) and the text is 2D (no extrusion) for reference. Any thoughts on what I might be doing wrong or how I could get a smoother etching effect?

Before knife project:

After knife project:

Apply an Edge Split modifier to your object and then select the loop edges one for each letter-symbol (if I count correctly there should be 5) and then once you select them press Spacebar and search mark sharp and press Enter

Then in your Edge Split modifier select only Sharp Edges.

However this will only fix the solution 90%. If you zoom in really close to the area with the letters you will see some "unwanted" shading. In that case I would suggest to delete the letters and try what comments suggest.


material texture won't show up In the viewport, I can't see the texture I just applied to the object.

You are in solid preview mode. If you look, there are 4 little circles in the top-right of your viewport that represent the different preview modes (From left to right - Wireframe, Solid, Material Preview, Rendered Preview) - to view your textures, pick one of the two rightmost ones (Material Preview, or Rendered Preview). You can also press Z in the viewport and pick the correct preview mode from the pie menu that appears.


Animation Nodes - Have an effector control the rotation of many objects I am trying to wrap my head around animation nodes, I have followed This tutorial and it was easy to understand and do. However I am trying to do something a little different and I am completely lost.

In the attached picture all these objects are separated and put in a group. I would like to have my empty sphere control the rotation and falloff of each object. So I can show the tiles flipping over.

The above tutorial is only for making a grid from a single object, I don't need the grid and I have many objects. So I don't know how to convert this to what I need.

Any help with the node set up would be appreciated.

Your Question

We can compose a transformation matrix out of the locations, then generate the rotation matrix using the Offset Matrices Node and then set the objects transformations to this new matrices.

Warning - Make sure not change the locations of the matrices or set the locations of the object by mistake to any value.

Recommended

If your objects are exactly the same, then you can replicate them using the Object Instancer node and set their locations using thew Distribute matrices node (See my answer here: Answer):

Note - If the object has modifiers and you want to copy them, use Copy Full Object option in the Object Instancer.

If you objects are different, then you can replace the Object Instancer with the Object From Group just as you did.


Whenever I move an object the entire scene is re-rendered Whenever I move one of the objects in my scene, blender automatically re-renders the entire scene as if I had pressed the render button. How can I turn this off?

Figured it out after 11 minutes of painstaking button pushing.

Uncheck the box that says "auto render"


Store current region 3d I have to store the current region 3d for an object in a Python addon.

context.space_data.region_3d

But I have to create a copy of this, I dont want to store a reference, is this possible?

I need the location and rotation of the viewport when this object is created, so that I can manipulate it with the data of this, even when the user changes the current view zoom or rotation.

Ok, got it, just copied the required info I needed

class ViewContext():

    def __init__(self, context):
        rv3d           = context.space_data.region_3d
        self._view_rot = rv3d.view_rotation.copy()
        self._view_mat = rv3d.view_matrix.copy()
        self._pers_mat = rv3d.perspective_matrix.copy()
        self._view_pers = rv3d.view_perspective
        self._is_perspective = rv3d.is_perspective
        self._region = ViewRegion(context.region)


Two perpendicular faces are highlighted as one (upon selection) Two perpendicular faces are highlighted as one upon selection. Actually the upper one is not recognized as a separate face at all (it lacks the dot in the middle). How has it happened and how can I fix it?

What you might be dealing with here is called an "ngon".  It's a shape that has more than four vertices.
It looks like you made a face of all of these verts with one F command before the top edge was made, or something similar.  So blender has done its best to draw it in a way that makes sense, but that is one face, technically.
It also looks like you have a couple of rogue edges down at the bottom.
In this case it's an easy fix, just select this top edge:

And hit J which is the shortcut for Connect Vertex Path.  It creates edges or splits faces where needed.


Exporting Animation without IK targets, poles bones and other controls I've created a character that has been rigged with IKs constraints for legs and arms and some other custom controls implemented through other constraints applied on control bones (like a copy rotation that copies the rotation of a control bone on the spine bones with different weights for each bone).

I'm exporting this character to use it in a game engine and obviously, all the control bones are shown in the exported "skeleton". Is there a way to avoid some "secondary" bones to be exported? I'm only interested in the final animations I don't need to maintain the logic implemented through the constraints.

In pose mode you can select all bones you need and bake the animation into a new action, removing the constraints. The movements will be the same as if the constraints were still acting.


Eevee render doesn't look like render preview So when I render the model with EEVEE the render output is different from the render preview in viewport.

Eevee render viewport screenshot:

Eevee render output:

Why are they different?

This last is the output from cycles.

Cycles render:

How do I achieve something like in the first image with EEVEE and Cycles?!?

Check if Ambient Occlusion is on in the Render panel. That might make the object shadows disappear if it's off.


Installing Blender on iMac OS-10 I installed Blender on my laptop (Win-10) and things went well.  However, my desk top is an iMac (OS-10 Yosemite).  I have no understanding of the iMac -- at all.  I read the answer to a previous question and read the guide to install on OSx.  I am totally lost.  Can you help me further?
I am familiar with GNU since I have used the GNAT developer.

You just copy/place the Blender folder in your Applications folder. To start Blender open the folder inside Applications, double-click on Blender icon and that's it. You can also drag the Blender icon and put it in your Dock for easy access.


UV Unwrapping complex drilled cube I know that UV unwrapping is a black art, and I am just beginning to dabble in it and try and understand it. Most of the time with the things I need to unwrap either a Project From View or Smart Unwrap suffices. However I have come up against one scenario where neither will work, and all my attempts to manually unwrap have failed.

The object is basically a cube (extruded SVG shape consisting of 4 lines) into which (as you may have gathered from my other questions) lots of holes have been cut through it using a boolean modifier.

On fairly simple ones a smart unwrap works adequately, since I only need to texture the top and bottom surfaces. However when it gets more complex that fails, and you end up with a number of islands in a complete mess for one surface.  Manually adding seams around the edge of the model to slice it into 6 segments results in a complete and utter mess. Doing a cube projection ends up in a complete and utter mess.

So I am now trying to add seams around the ends of each and every hole drilled in the cube - however there are hundreds of them and doing it manually will take all week - with no guarantee of success.

Is this the right way to do it? Manually adding seams to the top and bottom edges of every hole drilled through the cube? Is there a faster way of selecting these edges to add seams? (the fastest way I have found so far is to look at it obliquely and do a box select around a hole in vertex mode, then add seam, then move on to the next hole).

I think part of the unwrapping nightmare I am having with this model is the horrible mess the boolean operator has made of the mesh. It seems to have made faces overlapping each other which isn't good. Not sure how I go about fixing that kind of thing. (update: adding enough subdivides to my cube solves that, and now I can use a smart unwrap, so this now isn't a problem as such, but good to know how to deal with this kind of thing in future).

Hit Shift+G in Edit mode while having one of the edges selected that you want to mark as a seam.

This brings up the select similar dialog which offers the possibility to select other elements by similar properties (in your example perhaps edge length)

Another way to speed things up is box selection (B) in edit mode or circle selection (C) in edit mode. If you want to get certain stuff out of the way while selecting hit H to hide elements. Just make sure you unhide them before you unwrap.


How can I render all the frames and not 1 frame at a time I am trying to render my intro on Blender but when I render it it only renders 1 frame at a time. Help? I need it to auto-render

Use the render animation button found in the render context of the properties editor (or Ctrl-F12).

If you are trying to create a video the best practice is to take those rendered images and add them to the video sequence editor as an image strip and then change the render settings to whatever video output you'd like and render the animation again.


How to get a object mask as part of the alpha channel? I am trying to get the middle sphere to render as a part of the alpha for the image. In the image below where I have the test grid image at the moment it really should be transparent. How do I do that?

If you are using cycles, all you have to do is use holdout sahder node.
 Give the object that you want to have the 0 alpha a new material like this.

Then in the render tab of the properties window, under the Film section enable Transparent. You will have to save your render to a image format with a alpha channel, such as a .png.


Is it possible to set rotation to the current meshes face? On the image below I have an Icosphere that has been separated into multiple triangle objects. My only problem with this is that I need the rotations for them to all be facing the correct way, but every object has the same rotation. Is it possible to set them all to look the same but also have the rotation values that correctly point in the direction from the face?

Thank you in advance.

Particles
Duplicate Settings
Explode Modifier

Particles with Rotation setting shown. Image Above.
Particles also has a billboard setting.  Particles can be made in real ... meaning into separate objects.


My objects fade out when I increment the opacity of my background image This is kind of strange. Whenever I increase the opacity of my background image, the opacity of the other objects surprisingly decrease. This is such a pain, and since I'm fairly new to Blender I can't seem to solve it.

I've looked for a solution on Google before asking, but couldn't come with anything handy.

Any ideas? Thanks.

PD: It's like if the background image were on top of my other objects. But I can't seem to find a way to change the placement between objects and background image (if this makes any sense at all).

The Setup you're currently using is quite common in modelling, as you usually want to compare a blueprint or sketch to your model and trace some elements of that. A feasible value for the Opacity would be around 0.3, so you can see your model more clearly, but still compare to your underlay.
If you want the underlay to really be behind the model you're creating, set the Toggle Switch just below the Opacity slider to 'Back'. See comparison screenshots below:
Front

Back


How should I update a script to 2.8 that uses the removed 'scene_update_pre' handler? so I'm having trouble with this script:

import bpy
import mathutils

cam = bpy.context.scene.objects['Camera']
obj = bpy.context.scene.objects['Cube']

def drive_shapekey(scene):
    obj_mat = cam.matrix_world.inverted() * obj.matrix_world

    obj_eul = obj_mat.to_euler('XYZ')
    cam_vec = obj_mat.to_translation().normalized()
    obj_vec = mathutils.Vector((0.0, 1.0, 0.0))
    obj_vec.rotate(obj_eul)
    difference = cam_vec.dot(obj_vec)

    key1 = obj.data.shape_keys.key_blocks["Key 1"]
    key1.value = difference

pre_handlers = bpy.app.handlers.scene_update_pre
[pre_handlers.remove(h) for h in pre_handlers if h.__name__ == "drive_shapekey"]
pre_handlers.append(drive_shapekey)

It's supposed to change a shapekey ("Key 1") value, based on the angle and position of a Camera relative to the position and angle of the Object possessing this shapekey.

Of course I have named all objects and shapekeys accordingly (at least I'm pretty darn sure).
It does not run in 2.8 Eevee (didn't test cycles). The error I get is:

  'bpy.app.handlers' object has no attribute 'scene_update_pre'

Which I looked up on google ofc, and apparently a number of commands from 2.79 don't work in 2.8 anymore, including some in this script.

So this thread talks about using the new commands instead. Apparently I am supposed to use the dependency graph instead of this bpy...sceneupdate-thingy.

I've never written anything in Python before and I have no clue about most of the code (apart from obvious stuff like the matrices and that def probably stands for definition or define.).

If someone could fix this script for me, I would be very happy. An explanation would be great, too, but don't waste your breath if you have better things to do. I just need it to work. Thanks in advance. :)

There are two thing that need to be updated:

Matrix multiplication is now written using @
bpy.app.handlers.depsgraph_update_pre should be used as handler

Unless I've missed something, this should be all the changes that are necessary.

import bpy
import mathutils

cam = bpy.context.scene.objects['Camera']
obj = bpy.context.scene.objects['Cube']

def drive_shapekey(scene):
    obj_mat = cam.matrix_world.inverted() @ obj.matrix_world

    obj_eul = obj_mat.to_euler('XYZ')
    cam_vec = obj_mat.to_translation().normalized()
    obj_vec = mathutils.Vector((0.0, 1.0, 0.0))
    obj_vec.rotate(obj_eul)
    difference = cam_vec.dot(obj_vec)

    key1 = obj.data.shape_keys.key_blocks["Key 1"]
    key1.value = difference

pre_handlers = bpy.app.handlers.depsgraph_update_pre
[pre_handlers.remove(h) for h in pre_handlers if h.__name__ == "drive_shapekey"]
pre_handlers.append(drive_shapekey)


Can I Move a mesh from Zbrush to Blender? There is a way to transfer a mesh from Zbrush to Blender?

I'm using Blender 2.77 and Zbrush 4R7.

Yes you can!

Export your model from ZBrush as .obj (Wavefront Object). Even the texture can be exported on this way.

Then in Blender, "File -> Import -> Wavefront OBJ..." Make sure you have "Image Search" checked on and it will look for and import the textures as a Blender Internal material.


How do I control the armature in weight paint mode? When in weight paint mode when I right click a bone it goes into object mode and selects the whole armature but what I want to do is manipulate the bones while in paint mode, as seen in tutorials, to either move a part out of the way or test the weight painting.

The armature has to be in Pose mode, then Shift-select the mesh and go into Weight Paint mode.

If you have selection set to Right-click in Preferences then:

Sample weight (color) with Ctrl LMB
Select bone with RMB

If you have selection set to Left-click in Preferences:

Sample weight (color) with Ctrl RMB
Select bone with  Ctrl LMB

Independently of Select with option:

Paint with LMB
Rotate, Move, Scale bone with R, G, S
Paint gradient with Alt LMB


Can't Fill Circle...? I'm just trying to make one circle... But when I put it down and set the fill to "Ngon" nothing happens...

Are you in edit mode or object mode? If it says object mode in the bottom tab, press TAB to go to edit mode, usually you can fill using F.

If you're in wireframe mode you can't see the faces, Z is the default shortcut to enter and get out of wireframe


Model/Mesh Fractures Im new to blender, and new to the site. Ive researched my questions on the internet, and asked a few people, and they all basically sent me here. So i was hoping that I could get some assistance.

So Im new to blender, and starting to model some of my own assets for a Game my colleagues and I are building. Here is my current dilemma.

As I venture further into my model, and I lop cut and drag, and I extract shapes and build I come out with amazing results. However, when I add a subsurface modifier, and start to do more intricate details, and adding little things here and there, I am finding that my mesh is starting to fracture. When I turn the subsurface modifier off, if all recorrects itself.

Im getting, for lack of a better term, "phantom" faces and
edges and these "semi filled" faces appear and I cant figure out how to get rid of them. Im spending HOURS trying to figure out how to repair all my beautiful work, and I really think that solving the actual problem is something I should think about doing. So please, any assistance, would be most appreciated.

I can add a couple of images to further my explanations, if needed and someone can tell me how.

Thanks Community

Chris

http://imgur.com/a/2GC7C

There are Faces inside your model that shouldn't be there.

The best way to remove them is in Edit Mode select the bottom edge press "X" and select  "Only Edges and Faces" from the drop down menu.

Also, selecting Smooth Shading in Object Mode will clean this up.


Crease edge not working I am following a tutorial where the tutor creases the edges with "Mean crease" set to 1. I am doing the same with Blender 2.8, but it is not working as expected. The edges crease a little bit, but does not get sharp.

I am having same amount of polys

Creasing has more to do with how subdivision surfaces interpret the edges, once a subdivision surface modifier is applied, see gif for demonstration.

If creasing isn't what you're after and you're trying to create a smoothing split by marking edges as sharp, you're going to want to do the following:

Select your object, and access 'Object Data' in the properties panel, and enable 'Auto Smooth'.

Increase the Auto Smooth angle to 180 (or any preferred value).
In edit mode, highlight the edges you want to mark as sharp and press CTRL+E (for edge actions), and choose 'Mark Sharp'.


Fluid failing to enter side channels in Blender 2.80 fluid simulation I have a fluid sim under Blender 2.80 which requires liquid to flow into a main structure and fill side channels off (imagine underground passages flooding or a storm drain backing up).

Past a certain relative width, I cannot get the 'liquid' to flow into these smaller side areas, even with a lowered viscosity; all the fluid does is gain height, as the level behind rises, and inch forward rather than flow in. The relative width of the side channels seem to be important as I've sized a test area to 5m x 5m, then magnified it to 50m x 50m and still have the same difficulty (Transforms applied, afterwards).

Having been through boundary type settings, viscosity settings, domain height (less volume is not necessarily better) and one or two other options (3am never is a good time to still be working, let alone remembering) can anybody suggest other parameters which will allow the simulation to unfold as hoped? A much higher resolution? Boundary subdivisions? Animal sacrifice?

I've reproduced the effect in the attached test file.

Thanks,
Quin.

First, in the Domain options Set Boundary to Free Slip. With just this change in the file you attached I got as far as this:

You could probably play with subdivisions / surface smoothing or make the timeline longer. It might also help to make the domain only as high as the obstacle, so the fluid doesn't overflow before filling the smaller channels.


How to render a very complex scene using Render Layers? So that the Alpha Over property is implicitly applied to every frame after I do it on the first frame.

I am using Cycles Render, and Blender 2.75

Edit - The full image has soldiers and the plane. One image has the plane and one image as only the soldiers.

The soldiers are animated, but are in a different layer than the plane. I want them to be rendered with the animation along with the plane without moving them to the same layer (using Render Layers.)

P.S. The soldier count will increase greatly later.

This is the soldier layer -

This is the plane layer-

This is the full one (both soldiers and plane) -

Okay, I'm going to get the ball rolling by answering your question at face value. Here's a simple alpha over composite with 2 Render Layers.

I have 2 Scene Layers active, and have assigned each scene layer to a render layer. You'll notice that the shadow is rendered on the ground layer. This is because both layers go into memory and the monkey casts a shadow on the ground even though the monkey is not rendered in  layer one. If (for memory reasons) you did not want the monkey to affect the render calculations for Render Layer 1, you would add an Exclude selection for layer 2 on the Ground Render Layer. If you did this it might help with the rendering load, but you would lose your shadow on the ground, and would have to render it another way. If your ground object was really complicated and heavy (rendering wise), you could add a second simple plane on a third layer that could be used to generate the shadows for your solider layer, and the composite the 3 layers together.


Can not join two vertices I'm a very beginner in Blender. I'm trying to connect two vertices laying on the same plane (these edges were a part of a face that I deleted earlier):

But when I select them and press J it shows the Could not connect vertices error. How to solve it? What I'm doing wrong?

J only works on faces that already exist, it's basically a shortcut to cut a face between vertices (like the knife tool but just for cutting a face between vertices with a single button press)
You want the F key for this one. It will "fill" an edge between the 2 vertices.
If you want to make a face from 3 or more vertices, select the vertices and hit F to make a face.
F can be used in many different situations, like simply selecting a single edge that has other edges connected to it and boom, instant face. Try it out!


Grease pencil and Unity I have made a face animation using Grease pencil on my 3D model and I exported the model as FBX to Unity. In Unity, I can't see the face. It's just blank on the 3D model. What happen to the face animation I have drawn?

I also tried converting the GP into mesh but when I tried converting it, it gave me this notice "Current GP strokes have no valid timing data, most timing options will be hidden!"

Short version: Render it out and make a Sprite Animation.
Long version:
Click on the Faces, where you draw the with your animation, of your Object.
Say "Object by selected". Now you have a extra Object.
Take the Camera and fix it to your Animation.
Render the whole GreasePencil Animation out. Just the GreasePencil. Use the Transparent Shader.
Create a Sprite Image, based on your rendered images.
Import your everything in Unity.
Give your Mesh the normal Materials and the FaceObject is a Sprite Image.
I learned it here.
https://www.udemy.com/course/blender-28-game-character-creation/learn/lecture/14405776#notes
I hope that helped:)


How to make scopes that actually magnify using materials like glass? I have been trying to create a scope (sniper scope) that actually uses glass shaped like a lens to magnify into objects (I know this is not conventional and not how they do it in normal fps games but I wanted to try this out). It wasn't entirely successful as when I tried to magnify it more, more I increased the IOR the more distorted it got. I've probably got something wrong, and is it even possible to do this, is there a way to fix this?
Basically do any of you have any idea on how to approach this as I think im on the wrong track.

It is posibbly to do it. Try building a Kepler or a Galilei scope. A kepler scope is easy to build, but the image is inverted. Here is one I made:

To zoom, scale up the objective lens along the point where the empty is located, or scale down all the other objects along that point. The background image is missing, replace it with anything to see the sope working.


Is there a way to fracture part of an object using the fracture modifier? Basically, I have an object (A) that is falling, hits the ground and then gets hit by another object (B).  When the A lands, it stays in tact.  Then B hits it and fractures using dynamic fracturing in the fracture modifier.  However, it fractures the object A entirely...but I only want the surface to fracture.  Is this possible?  Keep in mind no meshes can be separated in object A beforehand because it will fall apart in mid air before it hits the ground.

Here are some examples of the type of fracturing I want:

Thanks!

I guess you are still asking about how to fracture your cartridge/crowbar scene ?
I tried now with prefracture and one particle helper object and the fracture addon "timing" feature, where you basically can delay the FM simulation by x frames. This just simulates the intact object and records keyframes, then it plays it back as animated rigidbody. After Frame X is reached, the animated checkbox will be disabled by keyframe and simulation takes over.
The helper object was carefully placed near the supposed impact point of the crowbar, and additionally some weak constraints were created to hold the shards farther away from impact together. In this blend's case X was Frame 85.

Edit: in this case i even could disable the constraints entirely. Looked even a bit better :)

Looks like this:

But take a look into the blend I prepared here.

Edit: Reworked version of the new question blend:

I did the following:

Removed all modifiers from the cartridge
Removed solidify from ground, extruded it properly
Set origin to geometry on ground
Made the ground a Box shape, with 0.0 margin
Moved the helper into the cartridge, so its particles "intersect" it
Since the crowbar impacts 2 times, I duplicated the helper and moved it
added FM with Voronoi+Bisect and Extra Particles and Helper group
disabled Uniform in FM, executed fracture again
constraint settings: "vertex" (set the radius to a low value before switching to vertex !!!)
breaking angle to 5 degrees

Then I played a bit around with different angles, constraint settings (centroid vs. vertex, limits, search radius, breaking angles) but it turned out those were the best settings imho. You get 2 impacts with them without the cartridge sliding away too quickly. But it breaks a bit more than just making a hole into the surface. Note: the animated crowbar acts as if it had infinite mass (i assume) so changing its mass while being animated should have no effect in theory.

Edit: final attempt of mine, couldnt get much closer... although tweaking for a while. Converted the keyframe animation into deltas and rotated the cartridge... so it gets a better hit pattern according to the crowbar anim.
Not sure if there are still too many shards, note some variation in shard size adds up some detail (imho). If still too many, feel free to reduce particle amount in helpers or alternatively the shard count in FM (applies to uniform)
Tried hard so the top is smashed and the bottom stays relatively intact.


Set parent with automatic weight error So I have this Blender model:-

I tried  using ctrl P -> set parent with automatic weight. It shows an error code saying:

  "bone heat weighting: failed to find solution for one or more bones"

What can I do? Do check the blender file to check the my mistake(s).

that will happen sometimes and there is no solution but to add weights yourself. you could try with envolope weights too, but that wont always work either. you could try checking your scale rotation and location too. they should be at 0 0 0 for rotation and location, and 1 1 1 for scale. Also looking at your model, you have some complex things like the finger blasters, and I may be wrong, but it also looks really high poly, so that may be an issue.


How can I put the compositor viewer node result back into Cycles? I am doing this experiment with Compositor Nodes and Cycles Nodes. There are times where I want to blur an image from Cycles and to bring it into Compositor, simply blur it and back to Cycles.

I have a feeling that this is not possible. But maybe there is a trick to be able to do this in a way that even though it is not realtime, it can be triggered and bake as needed?

A simpler test is if I am using Compositor, load an image, blur it or make adjustment and then export it into Viewer Node, is there in anyway I could ready that "Viewer Node" image into Cycles? -->  I tried this does not quite work, I am getting pink color.

You could probably do this with multiple Render Layers:

first layer renders or loads an image and blurs the result as desired
second layer renders the rest and composite it with the result of 1, either directly or by loading an image texture from file saved in 1.

example:


UV unwrap ignores mirror on part of the mesh? So I made this character, or half of it while mirrored along X, as you can see here

But when I apply the mirror and try to unwrap the UV I get this

Notice how the mouth is different on one side, I don't understand it as it should be exactly the same. Everything else unwraps perfectly, and the only thing I did was work on that part of the mouth with the mirror invisible so I could see better from the inside. But I've looked at it and  it is definitely the exact same mesh on both sides. I've tested it a bunch of times now, same result every time. Mark seams, apply mirror, unwrap, and the mouth area is always wrong. Any ideas to why this would happen?

I had this same issue and it was doing my head in, but it turned out because the mouth and face were separate materials, the pinning of the face were messing with the mouth.


How to switch back to default view after switching to camera view in blender 2.92 I am using the awesome Blender 3d Software
I can switch to camera view using ctrl+alt+0

But how to switch back to normal view which was earlier before navigating to camera view

I don't know if I understand the question, but the hints given here with switching the layout and using the pie menu make me think I'm completely wrong. What I read in your question is, you were navigating in the 3D Viewport and hit Ctrl+Alt+Numpad 0. This is the shortcout for Align Active Camera to View. This means, your camera is aligned to what you see in the viewport in that moment and this is the new camera view.
Usually you only have to press Numpad 0 to switch between Camera Perspective and the normal navigation view, the User Perspective. Let's say the camera's looking on the left side of an object, and you navigate your view to the right side. Numpad 0 switches between left and right side view.
My problem is now to understand what you exactly want. Numpad 0 gets you to camera view and back to what it was before, you can toggle between them. This doesn't work if you move the viewport when in camera view, because it exits Camera Perspective and becomes the new User Perspective.
If however your camera is now looking differently at the scene than before, that's because you used Ctrl+Alt+Numpad 0. This moves the camera to a different location and rotation to fit the Camera Perspective to the active User Perspective. Switching views doesn't get your old camera view back because your camera is no longer in the same location as it was before.
To get it back the only thing you can do is Undo your action with Ctrl+Z, but as all undo actions this only works as long as you didn't do too much inbetween or didn't close and re-open your file.


smoke flow outwards from a source I'm trying to make a realistic rendition of the head of this character using a smoke simulation.

However I'm having a hard time getting the smoke to billow outwards from the face; it seems to only flow in a straight column whether using temperature difference or any of the wind settings. Should I crank up the strength of the turbulence field, or do you have some other ideas of how I might achieve this, another sort of force field maybe?

Here's my setup as it stands now:

Thanks for your help.

You may want to try using a particle system to control the smoke. If you add some normal velocity to the particles they will spread out form the head a lot more. Particles will still be affected by the force fields, but you will also have a number of other controls as well to control how they behave.


Loop cut and slide didn't complete the loop Not only that, the object is no longer manifold, and I haven't been able to fix it.
Look at the right side of the loop.

When a loop cut doesn't complete, it is usually because it hits a triangular face.

Before you did the loop cut, you have a misplaced quadrilateral. On the corner where the cut ends, there is an extra edge. If you move to the bottom corner of the object where the line is, there are two extra vertices.

The image below has the vertices highlighted.

Delete these vertices and then try and complete the loop cut.

You have to ensure that no extra faces like in your mesh exist. If a loop cut fails, your mesh will almost always have an error like this or a triangular face.

Good luck with your project and I hope I helped,

BFB


Script to select all vertices in an object and assign new vertex group I have a blender file which often has multiple objects in, which when they need editing together I have to assign a new vertex group to to easily select them.

Right now my process is;

Click the object,
Hit tab to select all vertices,
Go to Vertex Groups and hit add,
Rename it for that object,
Hit assign and be done.

Sometimes I have 20 objects so this gets repetitive. Is it possible to create a script in python that can do this for me, and possibly in a batch edit so it does it for all objects selected? If so, how would I go about it?

Thanks.

The code below is loops trough every selected object:

delete all vertex groups
create a new vertex group named as the object itself
then assigns every vertices in the object to the group

So all you need to do is, select your objects then Run Script.

import bpy
import sys
import logging
# config for logging
logging.basicConfig(level=logging.DEBUG)

def createVertexGroupForObject(aObject):
    # set to object mide : "VertexGroup.add(): cannot be called while object is in edit mode"
    bpy.ops.object.mode_set(mode='OBJECT')

    # remove all vertex groups
    for vertexGroup in aObject.vertex_groups:
        aObject.vertex_groups.remove(vertexGroup)

    # add new vertex group with the name of object
    newGroup = aObject.vertex_groups.new(aObject.name)

    # assign objects vertices to vertex group
    verticesToAdd = []
    for vertex in aObject.data.vertices:
        verticesToAdd.append(vertex.index)

    try:
        newGroup.add(verticesToAdd, 1.0, "ADD")
        logging.debug("\t\tvertex group added")
    except:
        logging.error(sys.exc_info())

# get selected objects
selected = bpy.context.selected_objects

for obj in selected:
    logging.debug("\tselected: " + obj.name)

    createVertexGroupForObject(obj)


Deleting vertices and edges In the attached image how can I delete the 2 highlighted vertices and edge and leave the surrounding edges, faces intact?

When I hit 'X' and select 'vertices', a gaping hole is created with adjoining faces/edges deleted.

In Edge Select mode (keyboard shortcut 2), select the edge you want to get rid of, press the space bar and type dissolve... then choose Dissolve Edges.


Zoom in and out without a mouse wheel I am using blender on a tablet, for those times when I can't plug a mouse into the tablet, I would like to still be able to zoom in and out on the viewport.

What ways are there to zoom in and out other than using the mouse wheel? I can't find any buttons or input boxes in the user interface that control the zoom of the view port.

Is it possible to enter a value somewhere for how far in or out the viewport is zoomed?

The simplest way to zoom with a tablet, in my opinion, is to use Emulate 3 Button Mouse from File > User Preferences > Input.

This allows you to zoom in and out with Alt+Ctrl+LMB  drag.

Then you can also orbit with Alt+LMB  drag. And you can pan with Shift+Alt+LMB  drag.


Ranining Cubes to form shape This is the .blend file I'm working with

I created this model with a processing sketch that translated colors into volumes. Now I'd like to have a rain of cubes, having the cubes to land in their proper position to build the batman image. How can I do this? animation node? collisions?

You can evaluate a Delay Falloff and use a multiple of the output as the z location of the objects as follows:

You may also randomize the order using the Offsets input.


Blender 2.8 Import Function does not find .obj or .ply file for import As the title says, my .obj file that I want to import into Blender does not show up at all after hitting "File" - "Import" - "Wavefront .obj" as if it doesn't exist.

It definitely exists in the correct folder as I can open it in File Explorer and I've tried dragging it into Blender with no luck. I've also tried a .ply version of the same file but it doesn't show up in Blender's search window either.

The weird part is that I've already imported nearly a dozen other .obj files from the same folder that are all exports from MagicaVoxel (Just like the new file I'm trying to import) with no issues at all.  Those files all show up perfectly fine in the Import window but my new files don't.

Trying to import into a new, blank blender file doesn't work and trying to open that file directly with Blender even causes Blender to CTD with no error message.

What's the deal here?

Dragging it into Blender won't help, as Blender's drag and drop handling doesn't auto-check the file type and apply the relevant importer (unfortunately!).

It's possible that when you select Import > Wavefront (.obj) the file is being filtered out of the view for some name-based reason. You can disable filtering in the top right corner to view all files without extension filtering.

If none of that works and the importer is having some problem with the actual file, you'll get some sort of error message in the system console. But it doesn't sound like you've got that far yet.

"trying to open that file directly with Blender even causes Blender to CTD with no error message."
That one would be a bug, then. It should be able to notice that you're trying to use Open on something that's not a .blend file and not crash, but it seems you have discovered a case where that isn't happening.


How to bake wireframe to texture? no i'm not referring to export uv i'm modeling an hard surface with subdivision, bevels and so on.
I would like to bake the final wireframe to texture, with all the subsurf, bevels, bools etc.
Is it possible?

I'm not sure this is exactly what you want but you could duplicate your object, apply all the modifiers to the copy, in Edit mode/Face Select mode, select all and inset individual faces (double i), give a color to the selection, invert selection and give another color to the wireframe, then bake the result?


UV textures not applying to skin modifier Please excuse the fact that I am a beginner in Blender. There may be something obvious that I am missing.

An exercise I tried recently:

1) Open a new blender default file.
2) Collapse all of the vertices of the cube to the centre.
3) Add the skin modifier to the object.
4) Extrude the vertex.
5) Open UV editing, and try to unwrap the mesh to apply texture.

I observed that I was unable to apply a texture to the mesh. I suspect that this is because of the fact that blender is trying to apply texture to the underlying mesh, rather to the mesh generated around the edges and vertices by the skin modifier. Would there be a way to UV map the skin generated mesh, and if so, what would that method be?

Thank you in advance.

Post Script:
if you have any criticism of this question, I would appreciate being told what it is, rather than just receiving a down-vote. Also, for this particular question, I spent several hours googling to try and find a solution, however, the Internet tends to siphon one into the most popular results, rather than the most helpful, but obscure, so it is entirely possible that I have simply been barking up the wrong tree.

You must Apply the skin modifier to be able to unwrap the mesh. Once applied, you will get acces to the generated mesh. Just press the "Apply" button in the modifier parameters.


How to line up armature and mesh after deleting the armature modifier? So I accidentally deleted the armature modifier and when I go to make another one, my object warps. When I try un-checking vertex groups, the armature will line up with the object again but I cant use it for animation. So how do I line up the armature and mesh with keeping vertex groups checked?

Before adding armature modifier

After adding armature modifier

To fix this follow the below steps:

Select your mesh
Hit ctrl+A and choose apply Scale
Do same step 2 and apply location and rotation
Select your armature
Switch to Pose mode
Hit Space Bar and choose "Apply Pose as Rest Pose"
Select Mesh then select armature and hit ctrl+P
Parent with automatic weighting

It will be working fine as shown below:


I can not get "track To"constraint to work on my eyes I have bones in the eyes names Eye.L and Eye.R I have bones in front of the eyes marked Eye_Look_At.L and Eye_Look_at.R - The course instructor says to add a "Track To" constraint on the Eye.L and Eye.R bones and choose "Armature" and the corresponding Eye look at bone. I have tried everything to try and move the eyes with the Eye_Look_At bones but nothing is working.

blend -  https://pasteall.org/blend/58c09422bd24405191af0c587d16b8e3

You just need to choose the right Track To direction, i.e. the bone axis that is supposed to point towards the Target, which in this case is Y, and it seems to work fine:


How to keyframe mesh vertices in Python I'm updating all the vertex coordinates of a mesh frame-by-frame in python and need to animate but can not figure out how. Here is a small abstracted script - the python isn't pretty, but it makes an icosphere gaussian hiccup (a little like this coarse GIF):

import bpy
import bmesh
import numpy as np

pi = np.pi
make_ico = bpy.ops.mesh.primitive_ico_sphere_add
ok = make_ico(subdivisions=3, size = 2.0, location = (0,0,3))

ao = bpy.context.active_object
oo = bpy.ops.object
ok = oo.mode_set(mode='EDIT')
me = bmesh.from_edit_mesh(ao.data)
ico0 = np.array([vert.co for vert in me.verts]) # get ico vertices
ok = oo.mode_set(mode='OBJECT')

n_frames = 101
bpy.context.scene.frame_end = n_frames

zmin, zmax = ico0[:,2].min(), ico0[:,2].max()
zc = np.linspace(zmin, zmaz, n_frames)

sig = 0.3
ico = np.zeros_like(ico0)
data = []
for i in range(n_frames):
    ico[:,:2] = (1.0 + np.exp(-(ico0[:,2] - zc[i])**2/(2.*sig**2)))[:,None] * ico0[:,:2]
    ico[:,2] = ico0[:,2]
    data.append(ico.copy())

for i_frame in range(n_frames):
    ok = oo.mode_set(mode='EDIT')
    me = bmesh.from_edit_mesh(ao.data)  #DO THIS EVERY TIME?
    for (vert, co) in zip(me.verts, data[i_frame]):
        vert.co = co
    bmesh.update_edit_mesh(ao.data)  # update
    ok = oo.mode_set(mode='OBJECT')
    bpy.context.scene.frame_current = i_frame + 1
    # something about keyframes HERE?

It is also possible to directly keyframe the positions of the mesh vertices
Edit updated for 2.8.
import bpy
from mathutils import Vector

def insert_keyframe(fcurves, frame, values):
    for fcu, val in zip(fcurves, values):
        fcu.keyframe_points.insert(frame, val, options={'FAST'})

obj = bpy.context.active_object
mesh = obj.data
action = bpy.data.actions.new("MeshAnimation")

mesh.animation_data_create()
mesh.animation_data.action = action

data_path = "vertices[%d].co"
vec_z = Vector((0.0, 0.0, 1.0))

frames = 0, 25, 50, 75, 100
values = 0.0, 3.0, 5.0, 3.0, 0.0

for v in mesh.vertices:
    fcurves = [action.fcurves.new(data_path % v.index, index =  i) for i in range(3)]
    co_rest = v.co

    for t, value in zip(frames, values):
        co_kf = co_rest + value * vec_z
        insert_keyframe(fcurves, t, co_kf)


Subsurface modifier has no "render" option I have a subsurface modifier on the character that I am working on. But at some point the "render" option just got ...bugged? (And I don't know when or why this happened) It doesn't look right and does not work for rendering either.

I can however change it to a multiresolution modifier and subdivide + render it that way.

However I would rather know what's going on here before going forward.

If you enable "Experimental" features (it looks like you have done that)

the subdivision modifier changes a bit and it allows "adaptive" subdivisions. You are not forced to use it though.

To not use the adaptive feature, just use the "Levels:" slider under it: it works exactly as the "Render:" slider works in the non-experimental version.

(you can switch back and forth, the value stays the same)


Sunlamp inside of a Cave So I'm working on a scene where I need to light a city inside a cave with four sunlamps, except when I add the cave box the light gets stopped by the cave. How can I stop that from happening?

Use spotlights instead. The sun lamp is a special case where the position of it doesn't matter, only it's direction. You could possibly choose to disable shadow rays (Object properties -> Visibility -> Ray Visibility: Shadow) but I doubt that you'll get the desired result.


How can I group Vertices for easy painting I am starting to paint my character with few basic colours, but there are multiple vertices throughout my mesh, is there a way to assign groups to specific vertices of that mesh, for when selected I can easily apply a material. Thanks!

Yes, its possible!

In Edit Mode, select the vertices. In the Object Data panel create a Vertex Group, name it what you want and hit Assign.

Now, in the 3D view menu, Tab back into Paint Mode and toggle Face Selection Masking for Painting . You will notice the masked areas are now grayed and can't be painted.


Emission Problems in Blender Render So I'm trying to make an intro for my youtube channel, and I made a shockwave effect for the background. It looks great, and as expected, my username without a material is pitch black in the render since it has no emissions on the material. But, when I do use even a fraction of an emission to help the colors pop out, the whole thing is blindingly bright. It doesn't even have to be an emission material! A lamp shining on the object is enough to recreate the same problem.

As you can see, the object is too bright, but it also doesn't show the true colors. I'm using a blue material and, get this, an orange material. I'm assuming the shockwave is providing light that is reflecting its own hue on the text. How do I make the true colors of my text pop out? (I also hope to give it some reflective lighting effects with a point lamp, but thats for another time.)

Since I can't yet comment, I have to reply as an "awnser."

You could maybe try rendering the username on a different scene with less light sources.


Setup an inverted pendulum simulation with BGE I'm very new to Blender. I'd like to setup a very simple rigid body physics system using the game engine. The system is simply a pole hinged in the middle of a block, which can move horizontally on a plane with friction, and walls to prevent it flying off the plane. It responds to a horizontal force that acts on the block, at every frame/timestep.

It's well known in engineering as the 2D cart/pole problem, aka inverted pendulum, and the rigid body equations are well known, but in Blender we don't need them! A simulation would start with the pole upright, and then apply random forces/impulses, (actuate it), horizontally on the block. When the pole falls below horizontal, its physically impossible for it to get back to vertical, and the simulation can end.

Setting this up procedurally would be a really nice/helpful introduction to rigid bodies and actuators in the BGE. I think in terms of the BGE/Physics the only scripting needed is to use a random, applyForce(...) or applyImpulse(...), on the block at each frame/timestep.

I'm not really sure that the game engine is needed for this simulation, only physics, as there is no user interaction? The output is just the sequence of rendered images, for a small time step/frames per second, and the value of the actuator/force applied at each timestep/frame.

Perhaps a the easiest place to start is from the [domino's tutotrial][4]

The things I'm stick on are,

How to hinge the rod to the block, I think I need a constraint, OR Maybe I should use a single armature bone ?
To apply a random force or impulse at each keyframe, I think I need something like bpy.ops.anim.keyframe_insert ?

I made a simple example in the game engine of a mouse controlled inverted pendulum. It answers only your question about the hinge, but maybe you can go from there.

The body block has a rigid body constraint, type hinge, target is the pole. The weight at the top is parented to the pole.

I'm sure it's not physically correct, but I had to change translation and rotation damping in the physics properties of the pole to have a chance at controlling the pendulum. I also reduced the mass of the pole.

If you'd like to have a look, here's the blend file:


Blender 2.8 (python) - how do I get the vector of the direction the camera points In python, how do I calculate/find/retrieve the XYZ vector from the location of the camera and through the midpoint of the camera view?

In the example below the camera is at location (7.4, -6.9, 5.0) and points at the origin (0,0,0); therefore the vector should be (-7.4, +6.9, -5.0)

I suspect the camera's location and rotation parameters hold the answer, but the I can't figure out the calculations.  For example, in moving the origin there is clearly movement along the Y axis, but the rotation on the Y-axis is zero so I don't know how to do it.

Since a clear rotation camera (0,0,0) point down z-axis.

So the vector should be $camera\ rotation\ matrix\times Vector(0,0,-1)$

In code:

v = Vector((0,0,-1)) #Down vector
v.rotate(camera.rotation_euler)

v #this vector

  Except

  Keep in mind that camera can have another transform by parent offset and some other modifier. If the camera rotation is not pure, you will need to apply the transform to that rotation as well.


How to fit an image to the UV Editor window's borders? I try to place the rendered image inside the UV Editor window so it fits its borders precisely. Unfortunatelly it isn't possible using a Mouse Wheel. Are there any ways to do it?


What are the differences between lamps in Cycles and Blender Internal? I've noticed that if I have an existing scene setup for Blender Internal and I switch to cycles, the lighting is completely off. I sometimes have had to start a new scene and import the models I want from the previous scene to get the lighting to work.
What is different in the way they work?

Cycles uses a physically correct light falloff by default, Blender Internal uses a smoothed falloff with a Distance parameter. Cycles can give a similar falloff by using the Light Falloff node with Smooth parameter.

Cycles lamp strength for point, spot and area lamps is specified in Watts, while Blender Internal has no clear physical unit that I know of. For Cycles this means you typically need higher values, as you couldn't use a 1W lamp to light a room, you need something stronger like a 100W lamp. For Blender Internal the default Distance of 30 means you can use lower strength values.

Sun lamps in Cycles are specified in $\frac{\text{Watts}}{\text{m}^2}$, which requires much smaller values like 1 $\frac{\text{Watt}}{\text{m}^2}$. This can be confusing, but specifying strength in Watts wouldn't have been convenient, the real sun for example has strength 384600000000000000000000000W. Emission shaders on meshes are also in $\frac{\text{Watts}}{\text{m}^2}$.


How to set transparent pixel in UV In my sprite UV i set it some UV to transparent in my pixel editor.
These pixels appear black in the viewport.

When I search about it I found various answers but for old blender versions, and the menus aren't the same at all now.

view capture

Assuming you're using Eevee:

Per my comment, I think the problem is that your PNG's alpha channel (the second output in your Texture Input node) is not being used to do anything, and Toon BSDF interprets the fully Transparent pixels as black by default. Because of this, I get the same problem with this image of mine, where everything Black is actually Transparent (pixels with alpha=0):

We can fix this by setting Material->Blend Mode to Alpha clip (this assumes you have already set Context->Render Engine->Eevee), Context->Film->Transparent, and using a slightly more complicated shader, which uses our PNG's alpha channel to explicitly control the mix factor between a Transparent BSDF and the color information in our Toon BSDF:

Note that the math node could also be deleted if you switched the order of the inputs to the Mix Shader node.


Split areas on a subdivded icosphere I created an icosphere with a subdivision level of 1. Then I added an EdgeSplit, a Solidify and a Bevel Modifier to the object. In the end I subdivided the whole icosphere. I am doing it this way because I want 20 areas which are then divided into smaller pieces and not 80 small pieces like it would happen when I would choose a subdivision level of 2.
Now it looks like this:

Now I want to split every of the 20 faces into 4 pieces. I am doing this by selecting the three middle vertexes and then use split.
Now it looks like this:

When I now try to do the same thing for the adjusting areas it does not work anymore. Maybe one vertex is already in use from the other area and therefore I can not use it anymore.
Is there any way to get the same result for every area?

In Edit Mode subdivide your Icosphere one time

Select all, and Split, Faces by Edges with ⌥ Alt + M

Change pivot point to individual origins and S to scale a bit smaller.

Add Solidify and Bevel modifiers in object mode.

Result:


Placing different types of Grass I'm trying to place two kinds of grass on a ground plane:

The exposed ground north of the east-west road should have short (Bahia) grass, with a sprinkling of weeds.
The exposed ground south of the east-west road should have long (Rye) grass, again with a sprinkling of weeds.
The ground covered by pavement or water should have no grass or weeds.

What I've read here and in grass tutorials suggests I'll need both vertex and weight groups:

Divide the ground plane into two vertex groups -- a Bahia group from the center of the road north and a Rye group from the center of the road south.
Weight-paint the ground so exposed ground has a weight of 1 and covered ground has a weight of 0. (Call this weight group Exposed Ground?)
Set the Bahia particle system to use both the Bahia vertex group and the Exposed Ground weight group for Density.
Set the Rye particle system to use both the Rye vertex group and the Exposed Ground weight group for Density.
Set the weed particle systems to use the Exposed Ground weight group for Density. If I don't specify a vertex group, the weed particle systems should emit from the entire plane, masked by the Exposed Ground weight group, yes?

Will these steps show tended grass north of the road and wild grass around the swamp in the south, with grass and weed particles emitting only from exposed ground?

Thanks in advance for your help!

Crissie

From what i know there is no such thing as Weight group in Blender.
What you need to do Crissie, is:

Create 3 vertex groups - north(reaching from the edge of the east-west road to the last north most vertex), south (reaching from east-west road edge to the north most vertex), and weed (those two earlier groups combined, so all terrain except the east-west road) and assign appropriate vertices with weight 1 to them.
Use weight paint to cover lake part with weight 0 for south group.
Use the same method to cover road and pavement with weight 0 for north group.
Use the same method to cover road,pavement and lake for weed group
Use north group for Density in Bahia particle system,
Use south group for Density in Rye particle system,
Use weed group for Density in weed particle system.


Blender Python: Declare Property Group (on the stack?) The questions keep coming, I know. I cannot find this simple answer anywhere. It may be because I'm not sure exactly how to phrase it in searches.

Is it possible to declare a variable of a custom type that is derived from bpy.types.PropertyGroup?

I have a situation where I create controls for the active object. But I would like to show these controls in a disabled state when there is no active object (or any object at all). So my (possibly terrible) idea is to declare a local variable of the property group used by objects and use the data in this temporary property group to draw the buttons and controls. I know I can just skip drawing the associated controls, but I don't like how disruptive it is to have the panel contents shift around when it happens.

Here is an example of what I mean:

class MyClass(bpy.types.PropertyGroup):
    Var : BoolProperty(
        name = "Stuff",
        description = "my stuff",
        default=False
        )

def draw_panel():

    if active_object:
        draw_buttons(active_object.MyProperties, disabled=false)
    else:
        temp_props = MyClass()
        draw_buttons(temp_props, disabled=true)

So the controls would be associated with a temporary property object. However, the code temp_props = MyClass() does not work. It appears that bpy_struct requires some type of "constructor parameter" (I'm not sure what these are called in python)?

If there is a better way to handle this, please feel free to slap me out of this idea. And in either case, how would one go about declaring a class derived from a property group or bpy_struct locally within a function? Is it even possible? I can't seem to find anything in the API docs about initializing one of these objects on our own.

One simple way to accomplish this is to set up a PointerProperty on the scene to store these values:

def register():
    bpy.utils.register_class(MyClass)
    bpy.types.Scene.temp_props = PointerProperty(type=MyClass)

Now you can reference the properties in your draw_buttons call with bpy.context.scene.temp_props:

def draw_panel():

    if active_object:
        draw_buttons(active_object.MyProperties, disabled=False)
    else:
        temp_props = bpy.context.scene.temp_props
        draw_buttons(temp_props, disabled=True)

You can also store the PointerProperty to many other ID structs from bpy.types (e.g. Object, World, ViewLayer, etc.).

(related: How do I register 'Scene' properties with Python in 2.8?)


Having trouble parenting cloth to armature I am doing the Clinton Jones (Pwnisher) Alternate Realities challenge, which for me, is my first big project. I am trying to perform the function whereby you parent the clothing item you've made for your character to the armature and do a data transfer from the body mesh to transfer vertex groups to the shirt. So far, I've been unsuccessful and I am unsure if the issue is that my body mesh came with an armature when I imported it in Daz so the name of the vertex groups differs from the base armature that the project file came with that I've retargeted my body mesh to or if it's something else.
All told, the big issue is that the arms are clipping through the sleeves so whether I'm able to solve this through rigging or other means is fine by me, I'm just at a loss for a solution so far. Project file here: https://gofile.io/d/KY3kGL.

You have a cloth simulation with a "runaway" animation. There are several problems with this. Mainly with the modifier stack.

the Mirror modifier on the shirt should be applied and removed from the stack.
the Armature modifier on the shirt has the wrong armature and the modifier should be on top
the Data Transfer modifier should be bound first, then applied and removed from the stack
the body mesh is rather high-poly (65k vertices) and has a (fortunately deactivated) Subdivision Surface modifier on it. The mesh is heavy for animation.

But even if you fix these issues the shirt has still weird deformations when the character is posed. And it gets worse if you run the animation. I afraid the topology of the shirt is not something that is ideal for this.
If this is your first big project it might be easier to make the shirt from the body. I would use a cloth simulation with an animated character only for cloth where it is really needed, like a tie, a skirt, or a dress.
To create a shirt from the body copy the body, add and apply a Decimate modifier with 2 un-subdivision iterations. Then add seams where the real-world cloth has seams (top of the shoulder, around the arms at the shoulders, and at the sides). Select the faces (L, limit to seams), duplicate them, and separate them. Remove the nipples and the belly button and grid fill the holes. Remove some edge loops at the front of the neck (it's not done in the screenshot).
Then go to Sculpt mode, and inflate the new shirt a little bit so it doesn't look so skin-tight. With the MultiRes modifier and Cloth brush you can more details and wrinkles. Bake the normal map from the MultiRes before you render animations. Add a Soldify modifier to give it some thickness if you like.

Finally, parent the armature (With Empty Groups), and transfer the weights from the body. Check the modifier stack and make sure the Armature modifier is on the top of the stack. Then it should deform fine.


How to texture a downloaded model made of stretched triangles? I'm a beginner in blender. Trying to texture a 3d furniture model which was downloaded from the manufacturer site. Geometry is made of stretched triangles. This causes problems of stretched texture which is visible on render.

I unwrapped the model with "smart uv project" but the geometry is still stretched
Is there any solution to texture it properly or I need to remodel it to make it quads?

What if I need to use dozens of real furniture models like this?
Should I model everything from scratch in blender?

some pictures to explain:enter image description here

This is caused by N-gons and double vertices.

If you only need simple shading, go Object > Shade flat and disable Autosmooth.

You can also use Mesh > Clean up > Limited dissolve to merge flat faces.
Before any larger changes, the mesh should be properly repaired.


Problem lookDevs blender 2.8 mode I have a problem, when I put in Lookdevs everything is dark, even having light in the scene, it appears the changes only when active up there, the option "Scene Ligths, but the reflections do not appear, I do not know how to solve, here Here's a print to better understand:

In the tutorial in question, it looks like this:

Thank you in advance for your help!

There's are 2 things that affect overall lighting in the scene

lights
world

The Look Dev viewport shading allows you to see what your objects would look like in predefined lighting conditions.  This is configurable to allow standard studio lighting setups which can be useful when modeling and animating.

You can override both the scene lights and the scene world to use the lighting from your scene.

In the general case, and unless you know what you are doing you should leave both boxes unchecked (as shown in the screenshot below).

Now, there is one other thing which may cause a problem.  If this is very small then the amount of ambient light will be low and you will have a dark Look Dev setup. Make sure that the world strength setting is something sensible (probably 1.0)

I hope this helps, there's a lot of learning in blender, but also a lot of fun too.


What is causing my frames to "flicker" after being rendered? I am having an issue in my renders where random frames are "flickering".  I am having the exact same issue this person was having and no one seemed to be able to answer his question:
 What causes rendered frame "flickering"?

Here is my animation with the issue: https://www.youtube.com/watch?v=UcIcOf4g3-g

I have put hours into finding a solution and I can't seem to find one.  Here are the solutions that I tried:

I have tried rendering with motion blur OFF and it fixes SOME frames.  Still not a definitive solution though.

I have messed with camera settings.

I have rendered the shadows separately and the meshes separately.

Rendered with GPU and CPU.

None of these seem to make a difference.

I don't believe this is z-fighting because no faces intersect with each other ever.

I am on a very tight deadline and I can't find a solution.  Please let me know if anyone knows a solution.

Dropbox link to the Blender file: https://www.dropbox.com/s/9q2jf745go6u1l9/flickering_problem.blend?dl=0

Well you have a scene lit by three sun lamps which is not very conventional, but that should not cause problems by itself.

The real source of the problem is that your lighting seems inconsequential and  the lamp placement random and not well thought out.

You lamp objects are intermittently inside and outside of animated objects. That will obviously lead to seemingly random lighting variations across frames.


Open Blender GUI from .py script Can I open GUI window from bpy module and control scene from script?

Example:

import bpy
bpy.context.window_manager.windows["Default"].open()

Blender built as a python module does not support a gui interface, it's runs as if blender was started in background mode. You can verify this by checking the background value

>>> import bpy
>>> bpy.app.background
True

If you are working on an addon, you can edit the scripts and then  disable/enable the addon to re-load the changes in blender. You may also want to look at the notes on remote debugging using eclipse.

You can open a text file in blender and run it as a script, you can reload the file after changes and then run it again. You may find the addon I link to in this answer helpful, the other answer there shows how to run a script straight from the file in blenders python console.


Cell Fracture Destruction I'm currently running into a weird issue with my scene and not sure how to overcome it. Firstly my cell fractured object with connections seems to be breaking before the ball hits it and when the ball hits the object not every connection is broken. Regardless of what threshold I use. Does anyone have any ideas?
Blend file:
https://pasteall.org/blend/a72bfbff307e424aacbc919d672b8026

Thanks,
Mitchell

delete all your constraints and your cells

select your original cube again, subdivide it 4 times then and hit F3 and restart cell fracture

use these settings (margin is important -> set to 0.01) and hit OK

before doing anything else hit M to move all created cells to a new collection - name it cells

on frame 25 keyframe "animated" for your sphere

on frame 26 uncheck animated and keyframe it

select one cell of your new collection

under physics properties hit rigid body

scroll all the way down and check "deactivated" and "start deactivated"

right click on your cells collection and choose "select objects"

then tap on object -> rigid body -> copy from active

start animation and it works

i made a quick video tutorial for you...but (!) this takes hours to upload, because my internet upload speed is slow as shit...so maybe in a couple of hours you can see it.
https://youtu.be/gizvc8fXhPY


Rendered frame doesn't match what is shown in rendered viewport There is 1 single frame out of a 1500 frame animation where the rendered image doesnt match whats happening in the scene. every other frame looks fine and is working as expected. As a result there is a noticeable stutter due to this 'dodgy' frame. I cant work out for the life of me what is causing it.

The frame just before it looks fine and so is the one after.

what ive tried:

disabled rendering on all objects and re-enabling them one by one to see if there were any overlapping geometry or object.
checking the graph editor for any mistakes in the animation of objects.
restarting blender multiple times.

So as i was writing the first part i tried to see what was going on 'behind the scenes' and i discovered something which makes me scratch my head till my scalp falls off.

The following renders are from the exact same frames as seen above but from the view of a different camera. ill let the images speak for themselves...

What you see in frame 451 actually occurs to frame 452 aswell but its flipped vertically.
The rectangles are emissive on one side and the backface is set to no material so it cant reflect or absorb any light.

And you'll just have to believe me when i say that everything looks normal in the rendered viewport. I can provide screenshots of the rendered viewport if you want proof.

edit 1-
Here is a screenshot which hopefully displays most of the info about the scene.
I believe it may be something to do with the way i animated the rectangle to spin. Its just supposed to rotate around the Y-axis at a constant rate. If my guess is correct i would still like to understand why this happens?

this screenshot should show that there are no modifiers on either light source and that the rendered viewport displays the image correctly. Rendered image is of frame 451

Many many thanks to any replies.

OK so I saw right with what i said in edit 1. After changing the animation in the graph editor the problem was fixed. Instead of setting the next frame back to 1° after it reaches 360° then repeating it, i made the line continue upward to 720° and onward.

note- the issue arose only when the frame was on 360° and 1°. both the rectangles opposite each needed to be changed. if only one was changed in the graph editor the issue still exists but with only half the "severity".

I still dont understand why this would cause such a thing to occur, an explanation as to why this happens would be great. Is this a bug?


Draw grease pencil over render without live rendering I am drawing a grease pencil layer over my subject based on a specific camera angle. The camera is locked, and the grease pencil strokes are being drawn while looking through it.

In order to draw the grease pencil layer properly, I need to be rendering the subject. However, if I viewport render, it impacts performance too much to comfortably draw. So I need some way to run a render and paint the grease pencil over it. I could render the subject and then paint over it with grease pencil in post, but I'm trying to keep the whole thing dynamic as there are other grease pencil elements that are not camera specific.

Is there a way to project a render back within the camera bounds so that it exactly lines up with the subject? Is there some other way to handle this issue?

The Background Images features for Cameras lets you do this easily. It lets you choose an image that will show in the Camera, with a variety of options for placement. If you choose Render Result and leave the rest default, then your render will exactly overlay the model. You can then hide the model and paint your grease pencil as needed.


High resolution Output for Blender 2.8 I need some advice for the output settings in Blender 2.8...

When I render an image with 2000px x 2000px the output has the resolution of 72x72.

Now when I render the same image with 3000px x 3000px the output resolution is... still 72x72. When zoomed in the image shows ugly pixels...

So: Is there a chance / way to have the resolution output at 300x300 (ppcm)? The only solution I came up with is to increase the image size massively... and therefore the rendertimes insanely.

Let's see if you guys can come up with an answer. Thnx

I think you mean dpi – dots per inch – markets default high resolution print setting.
If you're not printing, only pixel resolution matters, and it's basically the same scenario with a different resolution:

a 3000x3000px image at 72 dpi is 105x105cm.
a 3000x3000px image at 300 dpi is 25x25cm.

A high dpi image not necessarily will be crystal clear when you zoom in. Only the size in pixels count when you're looking at the screen.


How to see several texture slots at once? (cycles) I am trying to paint a model with the help of texture slots to layer the colors, problem is, the things I paint on the new, transparent texture slot won't appear and I have no idea why..?

To see the effect of a new image added in the material draw mode when painting, be sure to actually have it mixed into your other image as if you were dealing with layers in an image editor program. Here I use the image of alpha 1 and white as a base and another image with 0 alpha to overlay on top of the white image, mixed with factor of 1 in the color mix node before sending to the shader. I plug the alpha socket of the 0 alpha image into the mix factor of the color mix node to control how it mixes them, revealing the colors underneath in the other image.

 Remember to keep adding the images to the lower mix inputs, as Blender uses a top to bottom stack (like added lines of code in a text editor)versus the bottom to top style we see in image editors(like layers of acetate on top of each other). I believe the disconnected image node is mainly used for baking out a shader to a single image.


array modifier and parenting when I make lets say 3 cubes with the array modifier, apply and then separate in edit-mode I  have 3 cubes that behave differently in a parent child relation than when create the cubes otherwise (by adding or duplicating).
The array cubes in a parent relation do not edit simultaneously in editmode, while the ones created by adding or duplicating and put in a parent-child relation, do edit simultaneous in editmode.
Does the applied array modifier have an effect on the meshes later on when put in a parent-child relation? Or am I missing a setting somewhere?
Thx in advance!

The key concept here is linked data.

When you create geometry with the array modifier, all of the instances behave as a single object, they share the a common origin (or pivot point) and any changes made to the geometry of the original will be replicated in all of the instances.

If you apply the modifier you are creating a single object, comprised of copies of the original mesh, but the geometry of the independent meshes it contains is no longer shared. In other words: an object can have different disconnected meshes, and all of them will have a single origin (pivot point), but If you edit any of the meshes in edit mode, all others will remain unaffected as they do not share any data.

Likewise, if you Duplicate an object in object mode, or by adding, you create a completely separate object, that shares no mesh data with the original object. If you parent the objects they will behave as one in the sense that you can rotate, scale and move the parent, and all of the children will follow accordingly, but if you edit the mesh all of the meshes will be unaffected as they do not share the same mesh data.

If instead of a duplicate (⇧ Shift+D) you create a linked duplicate(⎇ Alt+D) you will create two objects that are independent, in the sense that they have different origins and can be rotated, scaled and moved independently, but they share the same data. Editing the mesh of one will change all of the copies that share the same linked data.

Look what happens in the outliner as the linked copies are being created, even though they are different objects (suzanne, suzanne.001 and suzanne.002) the mesh data is the same (suzanne as the original one)

Lastly, those independent objects that use the linked data can then be parented, so that they can be rotated, scaled and moved following the corresponding transformation on the parent object.


How do you allow an object to rotate around an axis? I am trying to create a wind turbine and I am wondering how to allow the blades to spin freely during the animation.  To specify,  I have a wind force field and a base with the blades of the turbine connected to  a rotor.  Here is an image:
I want the animation to start and when the wind blows I want the blades to spin but not fly away.  I would think that you need to use a rigid body constraint but after trying all the types it still flies away.  I am using blender 2.8.

I believe it would be easier to animate it, use shift + axis.

add a key-frame where it should start with the desired rotation, and then add other key frames where you want the 'fan' to turn and the angle of choice. (i chosen 359 because im not sure if i set it to 360 it would just not move, but go ahead and experiment! )

blender will automatically interpolate the key frames you set.

but if you really want accurate physics then im afraid i also don't know :(

but maybe this post will help.


Intersections in 3d model How can I remove some intersections in my model?
They cause wrong slicing for my printer.
The model consists of a path curve and a profile curve.
I use the bevel in the path curve with the object the profile curve.
I use Blender 2.8.
Thanks.

Blender 2.81 adds support for the Voxel Remesh operator, which can efficiently get rid of intersecting geometry such as meshes generated by tightly turning or self-intersecting beveled curves, for example this one:

The step by step process goes like this:

Ensure that the endpoints are capped - you can manually add faces later but since you are using a profile curve anyway, it's easy to add caps right here:

Convert the curve to mesh: Object -> Convert to -> Mesh From Curve/Surf/Meta/Text.

Press F3 (operator search) -> type "Voxel Remesh"

The result should now be something like this. Note that there are visible "welds" because the voxel resolution is not too big.

To adjust the parameters for the voxels, select the mesh, enter sculpt mode,

Then on the properties window adjust the settings for the remesh operation.


First time to try water simulation but I can't do it I used HDRI image to light my scene. I was just trying to learn how to simulate fluid. In the viewport, the fluid is in good shape:

But it renders the domain in the final image instead of rendering the particles, even after baking the simulation! how can I solve this?

In the newly updated fluid simulation (Mantaflow) you need to enable ‘Mesh’ in the settings. This uses the fluid particles (that you can see in your screenshot) into the final mesh. You may need to re-bake the simulation to see the result (there are some known issues with Replay cache mode not always auto-detecting that the simulation has changed and needs rebaking - try changing the Resolution or change the cache to Final to allow it to be baked).


Motion capture animations to IK rig I have .bvh (sometimes even .fbx) files with motion capture data that I want to retarget onto my own custom IK rig (or even a rigify one would be better).

The question is: How do I go about it?

The final product is supposed to be an IK rig that has a retargeted animation from .bvh.

I know of retargeting tools in Blender. Problem is: I can't get my head around the workflow. Can I retarget animations to IK rig? If no, how do I add IK after?

Most of the retargeting tools copy the bone rotations from the .bvh motion capture into FK bones of the rig. After that the animation can be copied to IK bones through FK/IK snapping scripts. When doing this manually from .bvh to a simple IK rig, you will encounter 2 difficulties:

Problem 1: The IK rig has extra control bones that the .bvh does not have. The rig structures differ. You need to add these bones to the .bvh rig and drive them with constrains from the motion captured bones. You have to usually add IK Pole bones, Hip location,.. (depends on the complexity of IK rig what you need to add) so you have all the bone locations and rotations to drive all the control bones of the IK rig:

Here the yellow bone tracks head of a bone up the chain and tail of a bone down the chain with 50% influence to stay right in between them. The green bones are just parented to yellow ones.

Problem 2: Usually the source .bvh armature has different proportions than the rig we need to transfer the capture to. When copying from FK to FK, there are not so many issues with proportions, because only the rotations get copied. IK rig on the other hand also relies on position of its controls. So before copying those, the .bvh source rig's bones have to be edited to proportion.