UV Sculpt tools not working at all in 2.82.7? I'm fairly new to Blender and this is my first unwrapping here.
I'd like to manually pull and pinch my UVs to reduce the stretch of the projected UVs, however, UV sculpt tools do absolutely nothing.

Here's a short clip illustrating my issue:
https://i.imgur.com/XQLBXBU.gifv

(i know those UVs aren't pretty, but hey, I'll get there)

What is preventing the tool from having any effect on the mesh? I remember trying it out in the beginning of the process and it seemed to work, but now it suddenly is defunct.

Thank you in advance.

Ok, it got solved through recreating all UVs from scratch again. I still have no idea what happened (probably a bug of sorts), but now it works. Sad that it made me lose a couple hours of work, though.


Vertex connected edge highlighting I am having an issue where the vertex that I have selected does not highlight connected edges. This happened sometime when I was modelling and it is starting to annoy me. Following this link, It says that un-checking the edge under mesh display would make the highlight disappear. I checked it and its still checked.

Loading a new file seems to display the edge highlighting and this leads to the assumption that I might have accidentally hit another shortcut that caused the edge to not highlight.

How can I fix this issue?

In this case the vertice wasn't highlighted as expected because the Mirror modifier, which was present in stack, had button Adjust Edit cage to modifier's result turned on.

This means the result of modifier's work was visible while in Edit mode and editable more or less (so you could select verts mirrored by it, for example).

But in this case part of mesh doesn't exist (because result isn't applied yet) and hence existing vertices of the mesh aren't highlighted as usual (when edges which are connected by these vertices are highlighted too) rather than one by one. Edge is being highlighted only when 2 vertices were selected.

Note: vertices' size is increased for demonstration purposes.

To work without this behaviour uncheck Adjust Edit cage to modifier's result in order to directly interact only with real vertices of the mesh. You can check it if needed to preview changes when it's important for the workflow.

Read more about interface of modifiers and meaning of the present buttons.


Blender 2.83 GPU render slows compared to CPU I am doing animations for over 3 years and i never came across the scenario that GPU render slower than CPU.
I m currently rendering a scene and the same scene is being rendered by CPU in 9 minutes and bu GPU in 47 minutes in cycles
CPU : Ryzen 7 2700x
GPU : GTX 1060 3GB
My question is that is this scenario makes sense because if you compare benchmarks both are more of less equal in render times ,, so why such a difference?
Is scene dependent on CPU or GPU or is there something wrong with either my software or hardware?

Issue solved.
I was using Blender 2.83.1 version
but 2 days ago new version came and i installed that and render times are around 4 5 minutes which is perfect.
So this was some kind of bug that is fixed now by blender.


Blender is rendering another project, and sequencer/compositing is un-checked under Post Processing. Why? when I go to Properties editor > Render > and click "Animate", it's rendering another scene... from a separate .blend file... that isn't open. I tried closing all instances of Blender, I tried searching online (most resulting in references to the "Blender is rendering an older version my project" thread on this site) and I tried playing around with the settings. There is nothing that I can see in the Video Sequence Editor. I have un-checked Compositing & Sequencer under Properties editor > Post Processing. I have tinkered around with settings and I just have no clue what's causing this issue. I'm still very new to Blender so this is something obvious, please forgive me.

Here is a link to the .blend file: https://drive.google.com/file/d/1wIZ96s0juEdrQXfOimYC1dTM_Jmg8VE3/view?usp=sharing.

If you're curious, here is a comparison of what the scene should look like, and the scene from the other file that it's rendering (for some reason). Note that when I click "Render" it renders individual frames fine. It's just when I click "Animation" that it does this:

I forgot I keyframed the Focal Length from very small to big for a zooming in effect in each file, making them look similar. I’ll escort myself out now...


How to clump hair particles from its root? How can I achieve No. 2?

Thanks!

Choose Clump -1 as explained by the manual: https://docs.blender.org/manual/en/dev/physics/particles/emitter/children.html


Blender 2.8 python - Add Texture Image I've been attempting to create a meterial, and add different textures to the properties using a script. I am testing with just a diffuse/color first, but am having trouble getting it to work.

I've tried various posts' answers, and even Blender 2.8 documentation and they all throw errors.

Blender code:

`bpy.ops.node.add_file(filepath="C:\Users\myName\Downloads\Textures\Downloaded\flooring5.jpg", filter_blender=False, filter_backup=False, filter_image=True, filter_movie=True, filter_python=False, filter_font=False, filter_sound=False, filter_text=False, filter_btx=False, filter_collada=False, filter_alembic=False, filter_folder=True, filter_blenlib=False, filemode=9, relative_path=True, show_multiview=False, use_multiview=False, display_type='DEFAULT', sort_method='FILE_SORT_ALPHA', name="Image")`

My Error:

location: <unknown location>:-1
Error:   File "C:\Users\nmaestre\Desktop\Projects\TextureShapes\TextureMesh.blend\Text", line 48
SyntaxError: (unicode error) 'unicodeescape' codec can't decode bytes in position 2-3: truncated \UXXXXXXXX escape

Pic for ref

Current Working Code: (i found this from another post)

#Import python
import bpy

# Clear all nodes in a mat
def clear_material( material ):
    if material.node_tree:
        material.node_tree.links.clear()
        material.node_tree.nodes.clear()

# Create a node corresponding to a defined group
def instanciate_group( nodes, group_name ):
    group = nodes.new( type = 'ShaderNodeGroup' )
    group.node_tree = bpy.data.node_groups[group_name]

#ref materials
materials = bpy.data.materials
#name material
mat_name = 'Mat_Tile'
# get ref to material
material = materials.get( mat_name )

#if not our mat
if not material:
    material = materials.new( mat_name )

# We clear it as we'll define it completely
clear_material( material )

material.use_nodes = True

nodes = material.node_tree.nodes
links = material.node_tree.links

output = nodes.new( type = 'ShaderNodeOutputMaterial' )

diffuse = nodes.new( type = 'ShaderNodeBsdfDiffuse' )

#input = nodes.new( type = 'ShaderNodeTexImage')

#With names
link = links.new( diffuse.outputs['BSDF'], output.inputs['Surface'])
#Or with indices
#link = links.new( diffuse.outputs[0], output.inputs[0] )

I found a combination of other user's code with some debugging to get a working solution for now.

#Import python
import bpy
from bpy import context, data, ops

mat = bpy.data.materials.new(name="New_Mat")
mat.use_nodes = True
bsdf = mat.node_tree.nodes["Principled BSDF"]
texImage = mat.node_tree.nodes.new('ShaderNodeTexImage')
texImage.image = bpy.data.images.load("C:\\Users\\myName\\Downloads\\Textures\\Downloaded\\flooring5.jpg")
mat.node_tree.links.new(bsdf.inputs['Base Color'], texImage.outputs['Color'])

ob = context.view_layer.objects.active

# Assign it to object
if ob.data.materials:
    ob.data.materials[0] = mat
else:
    ob.data.materials.append(mat)


How do I join two objects without having the modifiers disappear? How could I join two object and maintain the modifiers?

Once I join the roof and walls, the straw (which is done as modifier) disappears.

Is there solution for it this?

Go to the modifiers tab on the side and press the apply button.

Please note that modifiers won't actually change the mesh of your object until you apply them. Before that it will just show you what it would look like in the viewport. I hope this helps!


How do I merge all of these objects into one, and only using one material and texture to apply colors using a UV color grid? I was wondering on how I'm able to join all of these separate objects into one, and be able to apply one material using a UV texture with a color grid? is there any tutorials on youtube? Im only used to maya UV texturing. thanks.

To join the objects, select them and then press CTRL + J.
but I imagine you only need a color grid material for all the objects in the scene and not really having them joined.

the easiest and fastest way to achieve this requires using and external addon.
http://renderhjs.net/textools/blender/

Once you have the addon installed you can just select all the objects in the scene (no need to join them) and assuming you already UV unwrap them, then in the UV window under the TexTools tab just press Checker Map. if you keep pressing Checker Map it will scroll between various grids


Why do seam edges move together? I have a cube where I am trying to move one UV edge that happens to be a seam. My understanding is that since the edge is marked as a seam, it should be separate from surrounding edges, but when I move the edge other vertices/edges move as well. Why does it do this? Specifically, since the edge is marked as a seem, shouldn't it be moving independently?

Thanks,

Make sure you have the Edge Selection enabled (3 vertical line icon), as well as the individual vertex selected (3 white dots).


Blender game: How can I make a ball roll while moving? I'm making a game where a robotic ball moves, collects objects and passes obstacles, and my question is :

how can I make the ball roll while it is moving ?

l'm familiar with how to make collectible game objects and with in game animation but l just don't known how to make a ball roll while moving. l understand how to program with the logic bricks.

Torque causes rotational motion; therefore, applying torque will make the ball roll. This can be done with logic bricks or with python.

For both ways start out on the ball's physics, set Physics Type to Ridge Body and adjust the radius to the the size of the ball.

Logic bricks

Then on the ball add a Motion actuator. On the motion actuator, uncheck use local torque (the L on the right) and set the torque on one of the axes.

Connect keyboard sensors to the motion actuators with corresponding torque for the axis.

Python

Using python, create a text block and add this script.

from bge import logic, events

cont = logic.getCurrentController()
keyboard = logic.keyboard.events

x, y = 0, 0

if keyboard[events.UPARROWKEY]: x += 1
if keyboard[events.DOWNARROWKEY]: x -= 1
if keyboard[events.LEFTARROWKEY]: y += 1
if keyboard[events.RIGHTARROWKEY]: y -= 1

cont.owner.applyTorque((x, y, 0))

Then connect an Always sensor to a Python controller and activate TRUE level triggering.

Result
The logic bricks or script will roll the ball. *This is a monkey shaped ball.*


how to reference which particle system the current object is using? is there a way in python to reference which particle system an object is referring to?
for example, I have a mesh named 'cube' with a particle system called 'cube_particle'. if I delete it, then I append the cube again, the second 'cube' would have a particle system called 'cube_particle.001'. if there are multiple objects, it could become quite a mess to reference which one is using which.
in python, bpy.context.active_object.particle_systems["cube_particle"] can only get object depended property such as bpy.context.object.particle_systems["cube_particle"].child_seed = 0
whereas bpy.data.particles["cube_particle.001"].child_nbr = 10, it is through bpy.data, not active_obj,
I am looking for some kind of operation to find a link between active_object.particle_systems[A] to data.particles[B].
for example, cube.001 's particle system cube_particle is currently linked to data.particles["cube_particle.002"]
thank you.

active_object.particle_systems[A].settings.name would return data.particles[B] in this case.


What is bone space, armature space, object space, world space, local space? So, I thought I understood Local space and World space but then I started seeing "Bone space", "Armature space", and "Object space" in tutorials. Now I'm just so confused. How do Bone, Armature, and Object spaces compare to World and Local spaces? I tried searching to no avail.

You don't have to go into detail. I'm sure I'll be able to figure things out in a minimal amount of information.

Thanks! :]

The description of spaces in the constraints section of the blender manual is fairly good: https://docs.blender.org/manual/en/latest/animation/constraints/interface/common.html#space-types
If you are familiar with the concept of local space vs world space, then object/armature/bone spaces are particular local spaces. Object space is the local space for a given object (e.g. mesh, curve, empty etc). Armature space is the object space of an armature, but is especially relevant in pose mode when contrasting with bone space, which is of course the local space for an individual bone.


Three.js export option is sometimes disabled I'm trying to export models from some format (.obj, .3ds, .blend) to Three.js but sometimes they can't be exported. Can someone explain why?

This is what happens:

The Three.js option in the export menu can't be selected.

In Blender there is a difference between active and selected,
typically its fine to think of active as last selected.

Notice when you select the object, its outline (or wire) color is brighter then other selected objects.

The poll only succeeds (i.e., the operator is only enabled) if bpy.context.active_object != None: see io_mesh_threejs/__init__.py:323.

This will be the case right after you deleted an object, imported models (e.g. OBJ) or certain operator calls. These operations can clear the active_object, although objects may still be selected.

Select any object (or set active_object to an object with python) before you open the File > Export panel.


Is there an add-on for batch STL importing? I've been able to track down add-ons for batch Obj import and batch STL export but I can't find one for batch STL import. Does anyone have a link to such an addon or have a python script?

Start with importing obj file:bpy.ops.import_scene.obj

Then you export the scene with bpy.ops.export_mesh.stl : doc

After doing this, you need to delete all instance inside your scene and loop the process again. Should be a fairly easy add-on without tricky point.


Set a bones matrix to a custom matrix I have a script in which I compute a custom matrix for each bone of a skeleton. I know I have switch to edit mode but then I read that the property edit_bone.matrix is read-only for bones. Now, because I know how matrices work, I thought, I would just set the bones matrix to Identity() (edit_bone.head to (0, 0, 0) and edit_bone.tail to (0, 1, 0)). But when I then do transform the bone the outcome is not what I expected. The script-snippet is the following:

for bone in self._data.edit_bones:
    ebone = armature.edit_bones.new(bone.name)
    # ebone.head = (0.0, 0.0, 0.0) # already default
    ebone.tail = (0.0, 1.0, 0.0)
    t_matrix = Matrix(bone.transform) # use blender-intern Matrix
    # the following call should set ebone.matrix to t_matrix
    # cannot do that directly, is currently wrong
    ebone.transform(t_matrix)
    print(t_matrix, ebone.matrix, sep='\n')

This gives the following output:

<Matrix 4x4 (-0.9665, -0.2564, -0.0119, 17.7405)
            ( 0.0171, -0.0183, -0.9997,  0.0280)
            ( 0.2561, -0.9664,  0.0221, -0.0120)
            ( 0.0000,  0.0000,  0.0000,  1.0000)>
<Matrix 4x4 (-0.0530, -0.0119,  0.9985, 17.7405)
            ( 0.0227, -0.9997, -0.0107,  0.0280)
            ( 0.9983,  0.0221,  0.0533, -0.0120)
            ( 0.0000,  0.0000,  0.0000,  1.0000)>

Notice how the translation is correct but I don't understand why the other part isn't. Can anyone give an insight what is going on and provide a solution to my problem?

bone.transform() also didn't work very well for me, so I used a method I found in a blenderartists post to extract the roll and tail from a matrix:

def vec_roll_to_mat3(vec, roll):
    target = Vector((0, 0.1, 0))
    nor = vec.normalized()
    axis = target.cross(nor)
    if axis.dot(axis) > 0.0000000001: # this seems to be the problem for some bones, no idea how to fix
        axis.normalize()
        theta = target.angle(nor)
        bMatrix = Matrix.Rotation(theta, 3, axis)
    else:
        updown = 1 if target.dot(nor) > 0 else -1
        bMatrix = Matrix.Scale(updown, 3)

        # C code:
        #bMatrix[0][0]=updown; bMatrix[1][0]=0.0;    bMatrix[2][0]=0.0;
        #bMatrix[0][1]=0.0;    bMatrix[1][1]=updown; bMatrix[2][1]=0.0;
        #bMatrix[0][2]=0.0;    bMatrix[1][2]=0.0;    bMatrix[2][2]=1.0;
        bMatrix[2][2] = 1.0

    rMatrix = Matrix.Rotation(roll, 3, nor)
    mat = rMatrix * bMatrix
    return mat

def mat3_to_vec_roll(mat):
    vec = mat.col[1]
    vecmat = vec_roll_to_mat3(mat.col[1], 0)
    vecmatinv = vecmat.inverted()
    rollmat = vecmatinv * mat
    roll = math.atan2(rollmat[0][2], rollmat[2][2])
    return vec, roll

Then, to set it:

tail, roll = mat3_to_vec_roll(matrix)
bone.head = matrix.to_translation()
bone.tail = tail*boneLength + bone.head
bone.roll = roll


How to make a rigid body go up? I have 2 cubes, I want them to collide with one “falling” upward and the other downward, i tried to make the mass -1 but it set it to 0.001kg and not -1. How can I make it “fall” upwards

Mass is different than weight. Having a negative mass would cause all sorts of physics problems.
There's no easy way to flip the gravity for one object without flipping it for all. However, what you can do is create a wind forcefield pushing one of your cubes up. I'm no expert so there could be a better way that I'm not aware of.


Generate faces form single mesh edge? My first post, and no im not suck in edit mode!

I downloaded a model of an oil rig from blend swap created by "B M." as i'm hoping to model one of my own.

Upon opening the blend file i noticed that the beam like support structures pictured below are modeled in a particular way where it looks to be single verts with edges that then somehow generates faces around it.

This don't seem to be the work of a modifier. Something seems to be going on under the 'Shape Tab' within 'Data Object' options, as when i tweak the 'Fill values' and the 'Bevel Factor' the geomerty generated around the faces of the single Vert and Edge begins to take shape / deform.

In sum

What is going on here?
how do i achieve this type of modeling?
what other applications could this type of modeling be used for?

Thank you in advance.

There are three distinct ways to do this.

Either use Bezier Curve objects. They have the advantage of being simple to edit for tubular structures, can easily bend and make curves, and can have custom sections

Use a mesh with a Wireframe modifier. It is fast to process and is a mesh, so can have a lot more modifiers on top than a bezier curve

Use a skin modifier. It is slower to process and computationally heavy to handle, but will generate cleaner topology and have proper intersections at the joints.


Checkered face on cube On cubes, one of the faces has a checkered face, that doesn't like to cooperate with what I am doing. Can someone shed some light on what exactly this face is, and what it's purpose is?

Basic ingredients of a mesh are triangles (tris), quadrilaterals (quads), and polygons with n sides (n > 4, n-gons). N-gon is the least often used, and indeed Blender's own support for true n-gon is fairly recent (2.63).

The lower right face of your problematic mesh is a concave quad. Normally, proper rendering of a concave polygon requires it to be decomposed/fragmented into several convex polygons, a doable operation but potentially expensive [PDF] for realtime display. Blender doesn't do such operation, blindly drawing a face for each connected edges in each polygons in a mesh, hence the "ghost face".

To avoid such occurence, manually convert the quad to tris (select the face, then press Ctrl-T) for the upper and lower part of the quad:


Add Bmesh to another Bmesh I'm using a scrip Subprogram of Animation nodes to merge that will merge a list of objects using Bmesh (Because it holds the UVs)

But now i'm stuck at merging two Bmesh as the picture below explains.

SO i've managed to do the trick using the answer of CoDEmanX here : enter link description here
Still very strict to use and have a high ms

import bpy

AN= bpy.data.node_groups['NodeTree']
L = AN.nodes["Data Interface"].value

def OB_list_joiner(L,b,n):

    ctx = bpy.context.copy()
    P=[]

    for v in L :
        o=v.copy()
        o.data=v.data.copy()
        P.append(o)

    for v in P:
        bpy.context.scene.objects.link(v)

    ctx['active_object'] = P[0]
    ctx['selected_objects'] = P
    ctx['selected_editable_bases'] = [bpy.context.scene.object_bases[ob.name] for ob in P]
    P[0].name = n
    bpy.ops.object.join(ctx)
    return P[0]

if N not in bpy.data.objects :
    O = OB_list_joiner(L,True,N)
else :
    O = bpy.data.objects[N]


How to precisely set orthographic scale I am trying to get an orthographic render out of Blender with precise accuracy. The scale that I would like is 1"=1'. To prepare my scene, I have changed units to Imperial with separate values. I then changed the output dimensions to 7200x5400 - so that I can get an 24"x18" output at 300ppi. My problem now is setting the orthographic scale. I have tried 12 (for 12 inches in a foot), but the resulting render is too small. After fiddling with the scale manually, I figure that I'd need something less than 7.4, but I don't know how to get a precise scale for my use case.

Unfortunately the answer by Duarte Farrajota Ramos does not address the orthographic scaling in imperial units. However, after pulling my hair out for a few hours, I finally understood that the Blender cameras do not respect the scene units (is this a bug?). So what I did was to set the orthographic scaling to 0.9144 so that it would match a yard (it seems that a yard is a better target than a foot) and then adjust the unit scaling in the scene properties, and voila, it works!


How to set a fixed background image as reference for sculpting? The background should be fixed and not change with the orientation of the model:

All the information I can find is about using background images for modelling reference, by using empties, planes etc... But they all stay fixed to the model and rotate along with it depending on the viewing angle. I just want the grey viewport background to be like a kind of wallpaper with all my reference images.

Is it possible to do this?

Example: Joe Menna uses this all the time in Zbrush, like in this movie (starting at 10:30).

It is possible!

A few steps needed for it though.

You have to use a camera for this to work, the camera can be set up so the boundaries are at the edges of the screen, activating "lock camera to view" (function is in my favorites menu) makes it then possible to look around and rotate the view while staying in the camera.
After setting up the camera view, we need to add a background image or images to the camera, each image can be placed on the screen and scaled to our liking, allowing us to make a collage like in the mentioned video. If you made a collage of all the references already, fine, less images to load and position.
Under the camera object in the "Background Images" header we have the "Add Image" button. Clicking on that gives us a new entry "Not Set" under which we can Open/Select an image either from disk or use an already loaded one in the scene by using the little image icon with the arrow down, left to the "Open" button.
Once the image is loaded/selected, we have options like color space, alpha, depth (here we chose back) as well as frame method, where i would go with crop, to keep the image in ratio rather then stretching it. Further there is the X and Y offset which allows us to position the image(s) where we want them. Lastly rotation and scale for the fine tuning as well as options for vertical and horizontal flipping.
Once a picture is set up we can set up more by repeating the 3rd and 4th step, til we have all the screen estate used up. It is even possible to pack in more images that would lay on top of each other and show or hide them depending on their need.

Don't forget to save the file and eventually pack the images in the .blend file to open the file and realize the images are gone.

With all that said, here a little visual demonstration:

Excuse the small size, the 2MB upload limit forced me to cut down on size. Hope it still shows the essential part, that is, it works.


Can't change Pose Position of Armatures to Rest with Alt-G,R,S combo I just started using blender a few days ago and I've been tinkering around with simple armature models. In previous attempts, when I wanted the armature reset, I would do the Alt-G,R,S combo or 'Clear Transform' but now it doesn't seem to work. Is there an alternative option to explicitly replace the pose position with the rest position?

Ideally, I'd like to actually use the "Rest Position" Armatures for pose changes.
Earlier, I've tried to look for a method like this just to give an idea of what I'm trying to do:
1. Copy the Armature from the "Rest Position" tab
2. Proceed to the "Pose Position" tab, delete the Pose Position and...
3. Replace it with the "Rest Position" Armature so I can translate it since I'm in "Pose Position" mode.
That hasn't worked out for me and I'm stumped.

Edit: Nvm, just found out that the difference between resetting the "Pose Position" and "Rest Position" is that "Rest Position" doesn't take into consideration the effect of the IK constraints.

In the properties panel, under the armature settings you can reset the pose to the rest position by selecting "Rest Position."


Reliable path for add-on data storage How can I use the python API to find the most reliable location that an add-on can use to store data like images, assets, etc. automatically?

It's important that this location:

doesn't change for different versions of blender
doesn't get deleted on system reboot like some temp folders
is available on every OS

One option I've found is to use bpy.utils.resource_path('USER') which ends in the version number (on windows C:\Users\blah\AppData\Roaming\Blender Foundation\Blender\2.78), but then do a relative jump to the folder above it. Is there a better way?

Set it once in the addons User Preferences.
Suggest using a property in  addon preferences  The user chooses the folder.  I had deleted this answer, as it is not "automatic", however setting a storage location once,  is IMO, not a huge overhead.
Modify the script in link with a folder property
class ExampleAddonPreferences(AddonPreferences):
    # this must match the addon name, use '__package__'
    # when defining this in a submodule of a python package.
    bl_idname = __name__

    assets_folder = StringProperty(
            name="Assets Folder",
            subtype='DIR_PATH',
            )

    def draw(self, context):
        layout = self.layout
        layout.label(text="This is a preferences view for our addon")
        layout.prop(self, "assets_folder")

And then when you need to access it
    preferences = context.preferences
    addon_prefs = preferences.addons[__name__].preferences

    assets_folder = addon_prefs.assets_folder


What is keeping the translate arrows from working on the 3D Manipulator Tool I can't figure out why my translate arrows are no longer working. If I use the tool bar or the hot keys I can get the rotate and scale to work as I would expect, but I can not get translate to do anything. It was working in a previous save, so I went back and compared and couldn't figure out any differences. I then proceeded with the old file and it stopped working again. Anyone have any thoughts? I tried changing the system ->selection to OpenGL Select as I found in one forum without luck. I haven't been able to get anything else to work. I've uploaded the file to my google drive if anyone would be kind enough to let me know why this super frustrating thing keeps happening. I'm assuming a setting keeps getting toggle on/off or something similar, but can't figure it out for the life of me.

https://drive.google.com/file/d/1UNvRaJPZeD5GIx_VaVf7pyUgePMDLXHg/view?usp=sharing

Thank you so much for your help,
Brendan

Snap to Grid is enabled (and the object is smaller than the grid)

The selection can be moved, you are just not providing an input that would be able to overcome the thereshold of the snap to increments.

If your object would have been 10 time bigger, you would now experiencing a stepping in using the grab tool, but as it's dimensions are small, you are not able to jump over the first step.

The solution would be to disable the "Snap suring transform" option.


Modeling workflow for symmetrical indented plane I'm fairly new to blender and don't have a good overlook of what can be done with the modifiers yet. Currently I have a plane with a more or less centered ridge, now I wanted to make an X-crossing by copying that plane, turning it around 90 degrees and somehow combining it with the first one. However it don't find a way to do this.

Basically, I'm looking for function that aligns an object to the axis minima of 2 other objects. Or any other way to accomplish this.

Okay, here are some pictures to better show what I would like to acquire.

Assume I have a plane like this:

Now I copy this plane and rotate it around 90 degrees around the Z axis. The result looks like this from above:

And like this from below:

These two planes are joint to get a single object. Now what I would like to have is something like this:

This was done creating a second plane with a higher vertex count and using shrinkwrap. However, the curves in the "rift" are a bit smoothed and not as sharp as in the combined origin mesh. When I use projection for shrinkwrap I get artifacts.

This was the best I was able to get. Is there a more simple method and/or a method which is more exact, meaning I get the sharp corners where the "rifts" are crossing?

starting with two objects like you describe:

Add a shrinkwrap modifier

to get something like this:

Some faces look beveled because the quads forming the mesh cannot accommodate the deformation properly.
To correct the topology of the edges in question, there are two options:

1: Press Ctrl T to triangulate the mesh.

2: Manually subdivide the offending faces selecting vertices and using J to join the edges.


script custom previews in a menu I want to know how to create a menu with previews for an add-on. Until now I know that this is related with the bpy.utils.preview. I'm making an add-on that appends objects from a .blend file, I know how to append objects but what I want to do is to create a menu with previews of the objects /(similar to the matcaps menu - see below), select them and then press an "import button" to append the object.
Here's some documentation about the module:
https://docs.blender.org/api/current/bpy.utils.previews.html
https://developer.blender.org/diffusion/B/browse/master/release/scripts/templates_py/ui_previews_dynamic_enum.py

Also, as this is an add-on I don't know if I should have a def register() and a def unregister() inside this .py file as well as in the __init__.py file.

By analyzing the two provided scripts, as well as the free version of Pro Lighting: Skies I was able to understand how to create a previews menu.

Here is my script that I commented in if you want to study it.
If you run it in Blender's text editor, it will create a panel at the bottom of the Object properties area.

The key parts of what you want to do are:

Create a property collection

This happens in the register function so only one is created. Because you want the the images folder to be predefined, we hard-code the location inside of the script. You also set a globally defined preview_collections variable to hold the collection. Then you create an EnumProperty to hold the images. This has a function to generate the images from the folder.

pcoll = bpy.utils.previews.new()
pcoll.images_location = bpy.path.abspath('//images')
preview_collections["thumbnail_previews"] = pcoll
bpy.types.Scene.my_thumbnails = EnumProperty(
    items=generate_previews(),
    )

Generate Previews

In the generate_previews function, we create a pcoll object that references the one we created in the register function.

def generate_previews():
    pcoll = preview_collections["thumbnail_previews"]
    image_location = pcoll.images_location
    VALID_EXTENSIONS = ('.png', '.jpg', '.jpeg')

    enum_items = []

    # Generate the thumbnails
    for i, image in enumerate(os.listdir(image_location)):
        if image.endswith(VALID_EXTENSIONS):
            filepath = os.path.join(image_location, image)
            thumb = pcoll.load(filepath, filepath, 'IMAGE')
            enum_items.append((image, image, "", thumb.icon_id, i))

    return enum_items

Access the values

We can then access this preview collection in any Blender UI Panel with

row=layout.row()
row.template_icon_view(context.scene, "my_thumbnails")

Or however else you named it. Then you can use bpy.context.Scene.my_thumbnails to access the currently selected image name. From there you can create an append button to append from a file based on the image name.

Using in an Addon

To use this method in an addon, you need to change a line in the Previews.py file. Instead of getting the location of the images folder based on the current .blend file, you need to get it based on the location of the addon. So change

pcoll.images_location = bpy.path.abspath('//images')

to

pcoll.images_location = os.path.join(os.path.dirname(__file__), "images")

In the __init__.py file, the register and unregister functions need to call the Previews.py's register and unregister functions.

def register():
    bpy.utils.register_module(__name__)
    Previews.register()

def unregister():
    bpy.utils.unregister_module(__name__)
    Previews.unregister()

And finally, because you use bpy.utils.register_module(__name__) you need to remove the register_class call in the Previews.py file to register the UI class, or it will be called twice.

# Delete this, as well as the one in the unregister function from Previews.py
bpy.utils.register_class(PreviewsExamplePanel)

I have updated the Gist on GitHub with the changes.


Image Texture box mapping - offsetting vectors on opposite sides? Lets take a cube for example. I put an Image texture on it with box mapping on. It all works well, but one thing I notice is that the opposite sides are using the exact same position of the texture, which makes sense of course.

However is there a way to offset the vector(s) so that the textures on opposite sides would be using the different position of the texture?

I tried offsetting using Geomtry: Normal data thinking that I could offset each vectors with the Normal data (-1.0 to 1.0), but I haven't had any success with this yet.

Geometry > Normal socket is the way.

If you separate the vector components with a Separate XYZ node you can use the desired axis as mask for combining whatever you like (colors, textures, even shaders).

Use use the desired axis as input for the Factor socket of a color mix node. Then plug whatever you want on each color input. In your case just use the same image texture node with different vector input for coordinates.

With a Vector Mapping you can transform it however you see fit independently.
I added an additional Vector Mapping node because the Normal output of the Geometry Node is in Worldspace, meaning if you moved or rotated the mesh it would always point to the same global side.

The image illustrates the same cube object viewed from different sides in two separate viewports.


camera image not rendering In Blender 2.8, I have applied a Background image of a sky-scape to the camera view and have hit render. However, the rendered image shows the cube and gray world background, not the cube and the sky background image. I have fiddled about with the settings but to no avail.

Any thoughts?

Edit 1

I believe this question to be different than the question, "Why won't my 'background' render" (of which this question was closed as a duplicate) because the image I have is a Background image. The question mentioned by Ketchup boy 2002 relates to an image applied to an empty, which apparently is not renderable.

Problem

This behavior is because Object Data > Background Images only shows the image in the viewport -- there is no physical image. An easy workaround uses compositing.

Workaround

First, go to the Render tab > Film dropdown and check Transparent. This will tell Blender to only render the cube as opposed to the cube and the gray background.

Next, switch from the Layout layout to the Compositing layout. Add an Input > Image node and use the bottom left button to select your image (it has already been added to your .blend file, so it should be there).

Add a Distort > Scale node and connect the Image node > Image output to the Scale node > Image input. Set the Scale node > dropdown to Render Size. Add a Color > Alpha Over node and connect the Scale node > Image output to the top Alpha Over node > Image input. Connect the Render Layers node > Image output to the bottom Alpha Over node > Image input. Connect the Alpha Over node > Image output to the Composite node > Image input. Your nodes should now look like this:

Render.


Play Rendered Animation is all gray I have created an animation that plays properly when I'm in normal object manipulation mode but when I try "Play Rendered Animation" it just shows a blank gray screen (below), though the /tmp/*.png values are changing. I have tried this with Blender Render and Cycles Render with the same output.

I definitely have a light source, and here is what it looks like when I simply click Render for the current frame:

What should be happening is that spacecraft in the image does a "flyby" of the planet. I am using Blender 2.76 and am very new; your help is much appreciated! I can't figure out how to attach the .blend file, but here are the error messages I have in the terminal:

Executing command:
'/Applications/Blender/blender.app/Contents/MacOS/blender -a -f 24 1.0 -s 1 -e 200 -j 1 /tmp/0001.png'
ndof: 3Dx driver not found
playanim_toscreen: no ibuf for picture '/tmp/0039.png'
playanim_toscreen: no ibuf for picture '/tmp/0052.png'
playanim_toscreen: no ibuf for picture '/tmp/0030.png'
playanim_toscreen: no ibuf for picture '/tmp/0035.png'
playanim_toscreen: no ibuf for picture '/tmp/0045.png'
playanim_toscreen: no ibuf for picture '/tmp/0052.png'

So there might be a number of things that are happening. Firstly, I would just create a folder and set it as the location where it saves all the rendered images. I personally don't like using the temp folder because there might be other stuff in there. Then you need to go to the Video Sequence Editor and select "open" and select all the images you rendered and the play it.

Here is a Tutorial

The other thing that is unlikely is maybe something is in front of the camera that is hidden to the viewport but isn't hidden in the render check this in the Outliner. If you want to do a test animation to see how things look just lower the settings and samples and then put it together and see how it looks or you can just play the animation in the viewport. Hope this helped, best of luck to you.


Why does this procedural material distort at larger scale? I'm trying to learn more about procedural textures, and I created a concrete texture loosely following a youtube tutorial. At the scale I worked at, it looked just like I wanted. However, when I tried to apply the texture at larger scales, pale stripes appear on the surface. It does not seem to be related to the mesh, but to something inherent in the texture.

.blend example: https://drive.google.com/open?id=1kInkSXyzw1h-rgxYs9mBZdOlMhCCb83c

Could someone tell me what went wrong here and how  can fix it?
Thank you in advance!

The culprit is this musgrave texture :

I set the dimension to 0.4 and the patterns disappeared. Try never going so low with the dimension parameter because it causes repeating patterns.


Tool sub-menus don't always appear I'll be short. When i use some Blender tools which should make a sub-menu appear in the left window, it doesn't always happen. For example, according to a tutorial I was following, I should have gotten the sub-menu you see in the picture after using "spin", but it doesn't appear. Maybe it's something related to the fact that I'm using Blender 2.75 while the tutorial uses some 2.5x? How can I get that sub-menu to appear?

Thank you in advance.

You just need to click the little 'plus icon' to open the 'Redo Panel':


Random crash while rendering I'm using Blender 2.75, 64 bits with two GTX-980.
I work with a script that render without issues with low resolutions (up to 480p). However, when I try to render with higher resolution the rendering process crash randomly with Error: EXCEPTION_ACCESS_VIOLATION. By randomly, I mean that sometimes it renders up to 10 images before crashing, and sometimes it crashes at the first one.
I've put two logs at the end (one successful and one failed) of the same frame being rendered at 720p.

How can I identify the source of this issue? I think that it has to do with some  performance preset, but I don't know what to look for.

Rendering successful

Fra:244 Mem:209.85M (0.00M, Peak 404.40M) | Remaining:00:02.05 | Mem:1331.54M, Peak:1331.54M | Scene, RenderLayer | Path Tracing Tile 9/9
Fra:244 Mem:209.85M (0.00M, Peak 404.40M) | Mem:1327.59M, Peak:1331.54M | Scene, RenderLayer | Finished
Fra:244 Mem:209.85M (0.00M, Peak 404.40M) | Compositing
Fra:244 Mem:209.85M (0.00M, Peak 404.40M) | Compositing | Determining resolution
Fra:244 Mem:209.85M (0.00M, Peak 404.40M) | Compositing | Initializing execution
Fra:244 Mem:219.73M (0.00M, Peak 404.40M) | Compositing | Tile 2-9
Fra:244 Mem:219.73M (0.00M, Peak 404.40M) | Compositing | Tile 2-9
Fra:244 Mem:219.73M (0.00M, Peak 404.40M) | Compositing | Tile 3-9
Fra:244 Mem:219.73M (0.00M, Peak 404.40M) | Compositing | Tile 4-9
Fra:244 Mem:219.73M (0.00M, Peak 404.40M) | Compositing | Tile 5-9
Fra:244 Mem:219.73M (0.00M, Peak 404.40M) | Compositing | Tile 6-9
Fra:244 Mem:219.73M (0.00M, Peak 404.40M)
Fra:244 Mem:219.73M (0.00M, Peak 404.40M) | Compositing | Tile 9-9
Fra:244 Mem:219.73M (0.00M, Peak 404.40M) | Compositing | Tile 9-9
| Compositing | Tile 9-9
Fra:244 Mem:219.73M (0.00M, Peak 404.40M) | Compositing | Deinitializing execution
Fra:244 Mem:219.73M (0.00M, Peak 404.40M) Sce: Scene Ve:0 Fa:0 La:0
Saved: D:\software\3dgenerator_blender\renderWrap\F_01_Original\Apt\lightNone\noPose\8febee5b-daa2-40de-8aac-754aeb1a486e.png
Time: 00:12.80 (Saving: 00:00.16)

Rendering failed

Fra:244 Mem:209.85M (0.00M, Peak 404.40M) | Remaining:00:02.11 | Mem:1331.54M, Peak:1331.54M | Scene, RenderLayer | Path Tracing Tile 9/9
Fra:244 Mem:209.85M (0.00M, Peak 404.40M) | Mem:1327.59M, Peak:1331.54M | Scene, RenderLayer | Finished
Fra:244 Mem:209.85M (0.00M, Peak 404.40M) | Compositing
Fra:244 Mem:209.85M (0.00M, Peak 404.40M) | Compositing | Determining resolution
Fra:244 Mem:209.85M (0.00M, Peak 404.40M) | Compositing | Initializing execution
Fra:244 Mem:219.73M (0.00M, Peak 404.40M) | Compositing | Tile 1-9
Fra:244 Mem:219.73M (0.00M, Peak 404.40M) | Compositing | Tile 2-9
Fra:244 Mem:219.73M (0.00M, Peak 404.40M) | Compositing | Tile 5-9
Fra:244 Mem:219.73M (0.00M, Peak 404.40M)
Fra:244 Mem:219.73M (0.00M, Peak 404.40M) | Compositing | Tile 9-9
Fra:244 Mem:219.73M (0.00M, Peak 404.40M) Sce:  Ve:0 Fa:0 La:0
Fra:244 Mem:219.73M (0.00M, Peak 404.40M) Sce:  Ve:0 Fa:0 La:0
Fra:244 Mem:219.73M (0.00M, Peak 404.40M) Sce:  Ve:0 Fa:0 La:0
Fra:244 Mem:219.73M (0.00M, Peak 404.40M) Sce:  Ve:0 Fa:0 La:0
Error: EXCEPTION_ACCESS_VIOLATION

I had the same problem and I think it's a threading issue.
(AFAIK the render engines are written in C++, so it's not surprising considering threading and memory management in C++ are a PITA).

You should keep your CPU levels to below around 50% for the blender-app.exe process.
In my case, if I bring down the threads to a max of 4, the scripts run without problems (still using all cores).
Slows it down somewhat, but at least it keeps running...

Something like this in a script file:

cd C:\Program Files\Blender Foundation\Blender
blender -b "your_blender_file.blend" -t 4 -a
pause

Hope it works for you.


How to setup reasonable ragdoll constraints between body parts? I'm trying to create a ragdoll to animate a falling person, following How To Make Any Rig Into a Rag Doll in Blender (Tutorial).
Basically, it means that you create a cube (rigid body) for each bone, and the connection between the bones is converted to an empty with a rigid body constraint that is set between every two cubes.
E.g. this is how my ragdoll looks like:

Note: The ragdoll is human size and 2m above the plane (so should fall once physics kicks in).
The second frame looks like this:

It looks like the ragdoll was hit by something really bad, not just obey gravity (what it should do) - the head is pulled backwards and the spine really breaks.
Here's a zoomed view of the spine area:

The highlighted object is the empty, and it's setup so that:

It has a generic physics body constraint.
There's a zero limit on the distance. This (I belive) means the two spine cubes cannot change distance from the empty - it should act as a hinge.
There's a bit of freedom in changing the angle (between objects?) - represents the common back of a person (non contortionist).

Why is there such a big change from the 1st frame to the second?
Note: I also tried with no angular limits (thinking the limits are outside the initial rotation and might cause an abrupt change), but it didn't seem to help.
For completeness, here's the .blend file for this.
Thanks.

FWIW, the simple answer for my question is that the constraints between objects are fine as they are.
There is some physics force or bug (yet to be determined) that causes this to happen. Why? Because if I move the whole ragdoll to somewhere else, this doesn't happen.
Added a followup question trying to identify what's that mysterious force, but the ragdoll "wiring" seems fine.


First move object with rigid body physics, then animate manually I'm trying to make an animation in which my object first drops on a surface by using rigid body physics but later rotates towards the camera driven with manual keyframe animation.

I know there is a "animation" button in the rigid body settings. However activating it seemed to completely remove the earlier physics-driven animation from my object.

Is there a way to first animate with rigid body and the continue the animation manually via keyframes?

You can use the Rigid Body Tools panel available from the toolshelf. Just setup your objects as normal, select the one you want to manually animate after the simulation and hit Bake To Keyframes.
(In this example, I have a cube as the active object with its mass set to brick and the plane as a passive object)

A dialog will popup, select the start and end frames and optionally the frame step and hit OK.

Once this is done you should see the rigid body simulation keyframes for the object appear in the timeline from the start and end frame you specified. You can then select the object and manually animate from thereon and even tweak the baked keyframes if you want.


Mesh with cloth simulation not responding to wind I came across a model of a boat, and I tried to add some wind and cloth simulations to the sails and flags. The sails respond to the wind, but the flags do not, they just fall. In both cases I followed the same procedure:
Get a bunch of vertices to act as the "pinning vertex group", reduce the mass to about 0.02, reduce springing to 1, bending to 0.3, and check self-collision.

Initially, I thought that maybe they were too high to interact with the wind, so I put another wind source beside them, and still nothing. Also of note is the flag on top of the 3rd mast. I have no idea what is going on with that, but I have a feeling that it's a result of the mesh trying to fall, but it keeps interacting with itself to create a mess.
My .blend file

The mesh is actually responding to the wind, but it takes a value of 20k force to make it respond as desired. The flag has a much larger distance to be suspended by the force of the wind so it takes a much greater force. The sails are suspended so they respond much more readily.

Try reducing the mass of the flag so that it doesn't take as much force.


How do I bend a cylinder like this? I'm adding a necklace to a character I have. I made a hollow cylinder and need to bend it to fit the model

One way could be use a cloth simulation, very rough example:

which  works like:

here after adding a subsurf (as last modifier)


Why doesn't updating a particle settings object `frame_start` field work? (in Blender 2.8) I am creating a ParticleSettings object from python (Blender 2.8). All of the properties are set correctly but for frame_start, which does not change. Any ideas of why?

ps = modifier.particle_system.settings
ps.count = num_particles
ps.frame_start = explosion_frame
ps.frame_end = explosion_frame + 2
ps.lifetime = FPS * 3
ps.emit_from = 'VOLUME'
ps.normal_factor = 3
ps.tangent_phase = 0.5
ps.tangent_factor = 3
print(ps.count, ps.frame_start, ps.frame_end, ps.lifetime, ps.emit_from, ps.normal_factor, ps.tangent_phase, ps.tangent_factor)

The problem was that I was setting frame_start first, to a value greater than the current (at the time) frame_end. frame_start needs to be less or equal than frame_end. The following version does work.

ps = modifier.particle_system.settings
ps.frame_end = explosion_frame + 2
ps.frame_start = explosion_frame


Strange reflections in EEVEE Is there a way to make the eevee scene look like the cycles one?

The problem here is that you are using Screen Space Reflections.
Eevee uses various shortcuts in order to get good visual renders with minimum render time. In the case of reflections, Screen Space Reflections usually produces results which are good enough in most situations - where everything that is 'Visible' (screen space) is mapped through any reflective surfaces to provide those reflections. This means that only things that are in 'line of sight' need to be rendered but has the downside that if anything would only be visible as a reflection that it will not be rendered.
In your example, the dark shadows you can see in the reflection are those bits of the scene which are not directly visible to the camera - ie, it is behind the cube. Since the reflection provides a view of that 'hidden' section, Eevee cannot render it - and so it shows as an additional dark shadow in the reflection.
The solution is to use a Light Probe (in this case you can use a Light Probe Plane on the floor) to give Eevee a hint as to what to consider for reflections.


Blender Internal renderer question How do I enable, for example, additive blending for a material? Do I need to use node? I am trying out to create a light ball.

I searched the internet but only found answers for cycles.

Edit:
The result should be like the first picture in this topic: How to get additive blending in cycles?

Using nodes would be only way to make additive blending for material.
Though If You're making a light ball in Blender Internal You don't need it. Just go to material, find Shading make Emit higher then 1, go to World, check Indirect Lighting switch Gather(right below Indirect Lighting) to Approximate and voila, You got ball, that emits light.


Low quality textures being baked to high poly mesh in cycles I want to bake a high poly spaceship to a low poly one in cycles. I do know the procedure(uv map the 2 objects, bake AO on the high poly mesh, select the high poly first, low poly later, then select 'Selected To Active' and press bake.) I have used a Ray distance of .02. But the problem is the low resolution texture I'm getting on the low poly mesh
Notice the jagged edges on the left ship?
The meshes were overlapping, I just seperated them after the bake to take a screenshot. Here is another image of the settings.

My question  is, how do I generate an even finer high res bake? Is there anything I'm missing out? Or any way to get Anti-aliasing done?(Not even sure if it applies here!)

When you baking something, you have to create new Image in Blender. There is no way to change existing image resolution in Blender, so you should create new one, bigger, put it in appropriate Image Texture node and bake again into new image.


Blender or CAD software for making a robot/character with swappable parts I would like to create a robot that is assembled from smaller, individual, and swappable parts. For example, the normal hands can be swapped with wolverine-like claws at the joint providing the same wrist rotation and mobility.

I understand that Blender is not as precise as actual CAD - Is blender actually useable for engineering?. However, I don't need extremely precision when different parts join. For example, in this SFV video - https://www.youtube.com/watch?v=grX4qILHIlU, Akuma has different hair styles and clothings, is Blender an appropriate tool for making characters with swappable parts?

Expanding a bit on Duarte Farrajot Ramos' comment above: if you want to engineer routinely, then there are more focussed tools than blender. For the purpose that you describe, blender might suit you fine.

I myself do use blender to prepare engineering models for simulations. Not needing some of the more advanced CAD features, blender turned out to be a practical and very cost effective tool for me with the added advantage that I can model and visualize results using the same tool.

When you want to do precision modelling there are a number of guides and tutorials available on how to tweak blender for that purpose:

Several relatively simple precision tips can be found in this answer: How to model effectively using exact measurements?
An older but very extensive tutorial can be found here: http://www.rab3d.com/tut_blen_precision_guide.php
blendermama has a nice collection of hints: http://blendermama.com/precision-work-in-blender.html
And there are some tutorials on youtube of course: https://www.youtube.com/watch?v=kOxN4CHeBPQ

There are also a number of addons that help: Edge Tools and Caliper from http://www.blender3darchitect.com/ (which also has great tutorials) as well as tinyCAD.


Why is my vault's bevel unevenly applied? I don't quite get what's going on. I tried everything: applied rotation, scale, tried re-making the geometry, and nothing works. Could it be that a slight misplacement of a vertex causes such a dramatic change in bevel? It makes no sense. This was created from being mirrored, but it won't apply right. I tried all modes, which I will show below. There is only one that works, but since it doesn't apply it evenly to the bottom portion, I cannot use it as it destroys the top. I need this in order to get the profiling right (otherwise it shows an ugly, impartial application which I demonstrate below as well).

Here are the different types of modes of bevel that I tried (note that they're exaggerated to show how they are unevenly applied).

Offset (note the twisting of one side and another side's disproportionate look):

Width (it looks OK, but it's not when the bevel is applied in excess because it shows that not everything is scaling in the same amount):

Depth (really weird--should not be such a dramatic difference!):

Percent (this is the only one that works relatively better, but it applies most heavily at top, whereas I need it to be applied to the bottom evenly, too):

Here's the reason for why I need the bevel:

Here's what happens when bevel is applied:

Any advice is greatly appreciated!

Note that the file is found here:

How do you get to Killarney?  Well, sir, I wouldn't start from here if
  I were you....

Just teasing.. I think some of this may have been be easier if executed before the array was applied. (Making an array out of arch-peak-to-arch-peak sections may still speed things up when adding detail?) This is a fix, rather than a solution, I'd like to know why the Bevel works the way it does.. whether the algorithm could be improved.

Make a copy of your existing path-curves (you can CtrlJ join them into one curve object to save time later) call it, say 'Miter Path'
Make a copy of your existing profile curve, and delete all but its flat base .. 'Molding Base'
Use the Molding Base as a the Bevel Object for your Miter Path. You now have a set of ribbons
With the ribbons anywhere you like in Z, select them, and then the Vault object. Put the (active) Vault into Edit Mode
From an orthogonal view down Z, hit 'Knife Project' in the Tool region. This will cut a set of edges into the vault where you would have liked the bevels to be.
There will be some extraneous vertices.. there are various ways of tidying them up ..  I selected one of them , then used Select > Similar > Number of Connecting Edges to find the rest, and then X > Limited Dissolve to get rid of them.
I also selected the penultimate vertices around the pole of the vault in order, hit J to make a ring of edges, and deleted the faces at the pole, assuming there will be some kind of boss or rosette there in the end.
Now you can delete the faces between the knife-projected edges and CtrlE > Bridge Edge loops creating the flat bevel to accommodate the molding. CtrlR cut a loop down the middle of each bevel.
ShiftD Duplicate the central loops of the bevel,
P separate to a new object, and AltC convert to a curve - U resolution 1 - this will be your new path for the molding profile
Move the origin of your molding profile to the center of its base - (this point will lie on the path). Use the molding profile as the Bevel Object for your new Molding Path. You may need to rotate it in Z in Edit Mode to get the molding to face the right way.

I apologize  for the lack of step-by step illustrations - everything important is done by step 5.

Alterations on Layer 11.


Fluid simulation render is distorted (video example included, Blender 2.75a) See video sample HERE

Here's another example

This has happened on multiple projects -- this was only a test project I made. When I create a fluid simulation, bake, and render it, some of the frames render out distorted (and those frames take a much longer time for Blender to render; the others work much quicker).

My question is, why is this happening? And is there a way to fix it?

UPDATE: Seems to be related to the motion blur, exclusively in the Cycles engine. When I turn motion blur off, the distortion - both geometry distortion and shading distortion - appear to be gone. When enabled, they occur.

Running Blender 2.75a x64 on Kubuntu 15.04 x64, KDE Plasma 5.3.2, and rendered with 2x Nvidia GTX 660's via Nvidia CUDA for Linux. Latest proprietary drivers used.

Thanks!

I discovered in other forums that this is a limitation with the fluid simulation and motion blur effect while rendering. Blender can't render a fluid simulation with motion blur, otherwise you end up with issues like these. Disabling motion blur will result in fluid rendering fine.


The window to set the textures is missing so I downloaded this gun online, and it has no textures. Usually their is a section on the right with many categories... one lets you add textures, but when I opened this blender file there was no option to add textures, here is a picture.

You don't have the properties window opened, where you will find the 'Textures' tab. If you look in the bottom right corner. There's a small cube with two arrows, next to the 'View' menu. Click that cube, and select 'Properties' to display that window.


Objects and physics not being rendered I was working on a scene with 2 groups of particles that were supposed to collide with an object.

I set the physics on the "collision object" to collision, in the preview the particles did collide, also in the render preview, but strangely in the final render the particles just went through the object.

I then started to watch tutorials to see if I did something wrong, nothing. As I'm kind of new in blender, I don't really understand the functions of some features, so I tried to bake everything and started messing with the cache in the particles settings.

Finally checked if the problem was in the particles settings or in the collision object, so I put another plain emitting particles into the same scene, still colliding with the object but with different settings.

Again in the preview everything was ok, also in render preview, but in the final render (both animated and only picture), neither the new plain nor the particles emitted appeared.

My conclusion is that the problem, has nothing to do with the particles or the collision object. I don't know if it's possible, but I think the final render is working with a previous version of the project.

I already checked the camera option in Cycles settings and the camera icon, that's not the problem.

Instead of using "collision" for the collider in the physics tab, use "rigid body" and uncheck "dynamic" (in the photo "dynamic" is checked)

and make sure it gets rendered.

In the particle tab of the emitter set Collision Group on RigidBodyWorld (it should appear if the collider is set as Rigid Body).

It should work.


Where did my bones go? I know they're still there, I can see them in the object hierarchy window, I can add and remove vertices to their component groups, but I cannot get them to display in the viewport. What did I do to cause this?

Blend file:
https://www.dropbox.com/s/vuvf2lpxyv5veq9/HK_HollowKnight.blend?dl=0

You messed up something with the workspace. I couldn't find out what, because in the menu the bones are checked in, but after I added a new Layout workspace I could see every bones.


Edge length wrong with scaling option Why is the edge length not changed when I scale the object?
As in the picture below, the description of the edge length is not changed from 2m after scaling.

Changes you make in Object Mode aren't taken into account in Edit Mode.
You need first to Apply Scale in Object Mode with ctrl A :

It will be reflected in Edit Mode:


3d function surface parameter entry I'm trying to follow a tutorial that involves using a 3d function surface, but in the tutorial, the location of the text entry field seems to have changed in the recent 2.8 update.

https://youtu.be/DqBOva04lcE?t=336

where can I locate the entry field shown in this video now?

After you add your math function mesh, on the bottom left of the 3D view you will see the operator editor (circled in middle image). Open it to view the various parameters of the operator you last executed, including the add math function mesh.


Hard/blur shade lines around newly added faces Im very much a beginner so the things ive tried are:

Pushing individual vertices deeper into the head this resulted in a decrease but not a fix:

Ive tried to use "Smooth Vertices" but this didnt help.
Reapplied subvision modifier but outcome didnt change.

Has anyone had this before and knows how to solve it or why this happens?
Added a picture of my mesh without subdiv modif visible in viewport.

Instead of creating new vertexes and then using the fill hotkey F, I was able to resolve this by extruding 2 new edges and merging vertexes with existing ones. Then extrude 2 more edges and merge all vertexes and in this way I created 4 new faces that dont have any issues. Still dont know what caused it but this worked to solve it atleast.


How do I restore the original window configuration? I have made a real mess of things. Each time I try to close one "viewport" or whatever they are called, another one is created, and now my entire screen is a MESS. I just want the original window configuration back, with Tools, Outline, and main window. Right now, I can't even access User Prefs, to see if that's how to do it because there's some kind of "wrench" over it, and it cannot be opened. Help?

In 'User Preferences' under the 'File' tab, you can uncheck the 'Load UI' option.

Save User Preferences.

Then restart Blender.

This will cause blender to load the default window layout.

If you want to keep a window layout, you need to remember to re-check 'Load UI' once blender has restarted.

To close individual panel, you can drag the corner with the arrow of neighboring panel with the same height or width. This is using the outliner to close the properties panel.

The link posted by @poor has this answer, you just have to wait until the end of a 30 second gif to see it in action.  (is there a TL;DW for gifs?)


Create a boundary mesh around complex mesh I have a mesh which has many faces and I want to create a simple mesh around it's shape to kinda form a bounding box around it's parts so that I have less faces and have simple bounds around the object shape.

As shown below I made an example of what I want to do, where a bound where set around the parts of the mesh. I want to know how this can be done for the whole mesh. My blend file can be found here

I made and addon that do this. actually work in 2.7.8 a. download

actually you need fix your mesh.

full video:
https://www.youtube.com/watch?v=CIMbexeP3aE


changing rotational axis this setup is rotating anticlockwise like a screw  (I've added the keyframes for the rotation) but now, I want to slant this set up a bit (30 degrees) when I do so, keyframed values are not working properly. I tried changing the pivot points and all, but nothing helped me. I did some research on the internet regarding this, but i cannot understand it clearly. I'm a very beginner to blender, please be kind enough to guide me through this.

-peace-

Create a controlling empty and use as parent.

Create an empty in a useful place.  Perhaps the base.
Parent the components to the empty.  You may choose to not include any object already parented to others. Do this by selecting the children first.  Select the parent last.

Press Ctrl-p
Select from the pop up menu

Rotate the empty which should rotate all the children in unison.


How to get the volumetric display not to show overlapping triangles I was following a tutorial online and ran into an issue with my system. (Using EVEE for the render)
I have a noise texture mapped into a emission shader then connected to the volume on the material output. I get these strange overlapping triangles instead of the look that the tutorial has. I have also increased the end and put the tile size to 2px in the volumetrics. I have included a screenshot.
My system is a Dell precision T7500 with an Nvidia K4000.
This happens on all versions of Blender that is final releases.
Thanks.

You need to reduce the 'End' setting to increase the number of volumetric 'slices' that are cutting through your volume.
Eevee renders volumes by effectively sampling a number of "slices" through the volume and combining the results. The samples are spread throughout your scene starting from the 'Start' volumetric distance and ending at the 'End' volumetric distance. By having your Start and End very far apart you are spreading out those samples and effectively wasting them over parts of your scene that don't include volumetrics.
Reduce your End until you just start to see your volumetrics "clipping" out of view (I'm guessing it will be around 5-10 (rather than 1000 that you have set). This will concentrate the volumetric rendering within your actual mesh rather than far beyond it - thereby drastically increasing the detail within your volume.
It's hard to tell scale from your screenshot - I'd assumed it was perhaps the default cube. Anyway, the key is to set Start and End each to just before it starts clipping your volume - so reduce End until you just start to lose some of your volume and then increase it slightly so it appears again. Then increase Start until it also just starts clipping your volume - then decrease slightly again so it just reappears. This way the Start is just on the boundary needed to see your volume while the End is also on the far boundary.
Note that if you're using the Viewport, the Start and End are in relation to the current view position in the scene - moving the viewport will potentially move your volume outside the Start/End clipping range and your volume will disappear. Same applies to camera view and when rendering.

Discovered during investigation that there seems to be a bug when the volume is purely emissive - adding any density changes the behaviour in ways it should not. Reported bug https://developer.blender.org/T85778 to allow this to be investigated as it results in odd results when adjusting the Start/End and/or Distribution Volumetrics settings.


Smoke Simulation Dissolve does not work I have another problem with smoke! I thought during rendering that the simulation just stops working but after a few tests, with an easier set up in another scene, it looks like dissolve of the smoke domain is not working right. In one frame all the smoke is there, in the next it is completely away.

This "Away" Frame moves when I change the dissolve parameter.
Please help me, I'm completely lost.
Thank you
Laura
Blend file: https://drive.google.com/file/d/1rRE-W2XO8i1YlcYtsUnCfLGOQTDS4ws6/view?usp=sharing

The Problem was the adaptive domain. It stops simulating with a small amount of smoke. Without it, it works


boat structure modeling - shape to curve along a surface I'm trying to model a boat structure using blender. I'm using curves or a subdivided mesh for the hull (outside shape) to define the outside. For the bulkheads (cross sections) I'm using planes and using a Boolean modifier to conform to the shape of the hull. This all works and is almost parametric in the sense that I can modify the outside shape of the boat and the bulkheads (cross sections) adjust to fill the outside shape.

What I'm stuck on is how to model the stringers (red parts in image). These are basically a bar (T bar or square bar essentially a rectangle) that conform to the inside of the hull.

From a blender modeling perspective - the question and problem I'm trying to solve is how to make a mesh or curve bend along the inside of a curved surface?

(I'm trying to model the red bars in the picture)

Both of these methods require a  set of edge-loops in the hull where you you would like the stringers to run.

A destructive method:

Select the loops which will become your stringers, ShiftD duplicate them, and P separate the selection to a new object
AltC in Object Mode, convert the new object into a curve
Set a full bevel, minimum resolution, on the curve in its Data tab, adjusting the depth.
In Edit Mode, all selected, set the Mean Tilt of the curve to 45 degrees
Assign a Shrinkwrap modifier to the curve, target the Hull, 'Nearest Vertex', 'Keep above Surface' with an Offset sufficient to raise the stringers onto the hull.

This method has a few disadvantages: Without adding a profile object, you can only have square-profile stringers.. you can change the shape of the hull a little and the stringers will follow, but not far before the Shrinkwrap goes out of range, and has to be applied.

A non-desructive method:

Make the selection of edge-loops as before, and make a Vertex Group from them
AltD make an instance of the entire hull
Add the illustrated modifiers to the instance, aimed at the Vertex Group.

The Bevel sets the width of your stringers (not necessarily 3 segments)
The Mask hides all vertices outside the bevel
The Solidify puts a thickness on the remaining faces, and sets the depth of your stringers

Now any changes you make to the hull will be reflected in the stringers, and widths and depths can be edited after the fact. You can add a further bevel, if you like, to round out the profile.

With appropriate  crease values put into the Solidify modifier, and in any Solidify assigned to the hull, both can  have a Subdivision modifier assigned, and stay in good shape.


Crop a portion of an image? I'm trying to do what I thought would be the simplest thing, which is to crop a portion of a screenshot of a webpage and zoom in on it (yes, I'm new to Blender).

After I've imported the image and added "Effect Strip" > "Transform" I can crop "Top" and "Right" (if I check "Image Offset" that is, otherwise it STRETCHES the image), but changing values in "Bottom" and "Left" just MOVES the image, it doesn't crop it.

What am I doing wrong?

instead of using the "video editor", you can use the "compositor". Add the image sequence, still image or video, then add a node "transform" and there, you set the X and Y values and scale. You can keyframe those values, so they can be animated, so the part of the image will gradually be cropped and zoomed (as you change the scale values) to fill the area you want.


Beveling an extruded object I've got this logo as svg vector file, extruded it to make it 3d and assigned a simple material. Now the edges should get beveled, but it doesn't work. Any tips?

The Bevel Tool won't work, because of too tight topology.
And without Clamp Overlap you'll get ugly artifacts.
You need to keep enough space for the beveled edges, use n-gons if necessary.


Box lid does not open right in animation https://www.reddit.com/r/BlenderDoughnuts/comments/ehcs83/y_is_it_doing_this_lol_help_please/?utm_source=share&utm_medium=web2x
The lid of the box can be positioned, but once the keyframe created, the rotation has completely changed to different things. Please see the video above.

No Option is available somehow.

The issue is that you want it to rotate on one axis only. However, the local axis for that object is not aligned in that direction, so Blender is trying to rotate it on both the x and y-axes to get it to that new position.

Here's a plane rotating the way you want it to. I've shown the local axis of the object to make it clearer how the plane is only rotating on its local Y-axis.

Now I've applied the transformations of the plane and applied keyframes in the same object positions. You can see how the local axes no longer align with the direction of rotation.

Uh oh! That is not looking good. So how do we fix it?

The first thing you want to do is to clear the object's animation keyframes.

Next, activate the Select tool while in Object mode. You're then going to need to go to the Active Tool and Workspace Settings tab. Under Options > Transform > Affect only, select Origins.

Now, select the box lid and rotate it with R. However, now you will only be rotating the object's origin, not the position of the object itself. Align one of the object's axis so it is normal to the plane of rotation (something that looks like the Y-axis in the first gif, this axis should stay in one place while the object is rotating).

After that, reposition your object and set the keyframes for your animation again.

PS: Nice job with the donut tutorial! I like what you've done with it.


Why does my computer freeze up when updating the preview window in cycles with gpu compute? Whenever I update a material with the rendered preview window open my entire computer freezes up and requires a reboot. This only occurs in cycles when using gpu compute. I have linked to a video showing how this occurs only with gpu compute. I can also link to the .blend is necessary.

Thanks for any help or ideas!

After further research I have found that amd gps are not completely compatible with blender cycles, could this be the reason for the crash?

Video

Go to the User preference and check for 2 things.

Is the correct Graphics card listed in the Compute Device section?
Is CUDA enabled or if your GPU actually support CUDA?

UPDATED ANSWER
Yes there is a limitation on the support for AMD GPU unfortunately, at the
moment it's pro nvidia. Feb 2016.


How to find number of animated frames in a scene via python? I need to find the number of animated frames after importing a bvh file  in blender. scene.frame_start and scene.frame_end only returns the start and end frames in the timeline.

My bvh file has 880 animated frames. How can I set my scene length automatically?

Could you please suggest a solution?

If the duration of the scene is known, simply use bpy.context.scene.frame_end and assign a custom duration value to it - this will overwrite the current playback/rendering range:

import bpy

# get the current scene
scn = bpy.context.scene

# assign new duration value
scn.frame_end = 880

In order to adjust the scene duration dynamically (based on the included animations) you'll need to iterate through all the relevant objects in the scene  and read their keyframes by using either Animation Data or Actions.

Keyframes via Animation Data

Use animation_data to get the keyframes of an object. Following example reads the keyframes of the selected objects and prints the first and the last keyframe to the console.

import bpy
import math

# get keyframes of object list
def get_keyframes(obj_list):
    keyframes = []
    for obj in obj_list:
        anim = obj.animation_data
        if anim is not None and anim.action is not None:
            for fcu in anim.action.fcurves:
                for keyframe in fcu.keyframe_points:
                    x, y = keyframe.co
                    if x not in keyframes:
                        keyframes.append((math.ceil(x)))
    return keyframes

# get all selected objects
selection = bpy.context.selected_objects

# check if selection is not empty
if selection:

    # get all frames with assigned keyframes
    keys = get_keyframes(selection)

    # print all keyframes
    print (keys)

    # print first and last keyframe
    print ("{} {}".format("first keyframe:", keys[0]))
    print ("{} {}".format("last keyframe:", keys[-1]))

else:
    print ('nothing selected')

Keyframes via Actions

Use bpy.data.actions to get a list of actions in the scene, but actions are not associated with objects, scenes or nodes. Following example reads the frame range of all F-Curves within the actions of the file and prints the first and the last keyframe to the console.

import bpy

# check if actions is empty
if bpy.data.actions:

    # get all actions
    action_list = [action.frame_range for action in bpy.data.actions]

    # sort, remove doubles and create a set
    keys = (sorted(set([item for sublist in action_list for item in sublist])))

    # print all keyframes
    print (keys)

    # print first and last keyframe
    print ("{} {}".format("first keyframe:", keys[0]))
    print ("{} {}".format("last keyframe:", keys[-1]))

else:
    print ("no actions")

Test scene

Console Output of both methods:

[1, 5, 7, 18, 21, 30, 47, 49, 67, 69, 75, 84, 100]
first keyframe: 1
last keyframe: 100

Speed comparison

Animation Data method takes 0.000446319580078125 sec.
Action method takes 0.00011038780212402344 sec.

Adjusting the timeline

As mentioned above, in order to set the beginning and end of the scene, you can assign the calculated values to bpy.context.scene.frame_start and bpy.context.scene.frame_end:

# get the current scene
scn = bpy.context.scene

# assign new starting frame
scn.frame_start = keys[0]

# assign new end frame
scn.frame_end = keys[-1]

Final Note

It really depends on what you want to achieve. Using animation_data is slower, but using action.frame_range can be dangerous, because if you have to delete an object during the process, the actions of the objects remain until the blend file is saved again. See: https://blender.stackexchange.com/a/27235/3710


Can't find the Shader/UVs tab I have a very basic problem: I want to create a 3D-logo. Therefore I imported a svg from Inkscape an extruded it. I know, that I have to select it in Object Mode, go to Edit Mode and then unwrap it in order to map the imported image on the 3D model.
But: there is no Shading/UVs tab. If I create a cylinder or a cube, the Shading/UVs tab is there, if I want to use my extruded object, the tab isn't.
What do I have to do to find the Shading/UVs tab? Why is it sometimes hidden and sometimes not??

Curves object's type doesn't have that panel

That panel is available only for Mesh type objects like the cube or the cylinder. Unrwapping is an operation related to faces, polygons, which in the filled and extruded curves are generated "on the fly" and not directly accessible.

Curves are an object type on their own, so you'll need to convert the curve to mesh in order to access those operators.


Can I let a tracking marker paint a mask? I want to do some retouching an a video shot and it would help to be able to use a marker to "paint" a mask.

By paint I mean how you paint with the grease pencil. But instead of your mouse cursor you use a tracking marker to paint.

Is there any way to do something like this?

EDIT: In my shot the actor pretends to spray paint a wall that is already finished (We forgot to shoot an important shot at the beginning). Now I tracked the sprayer and want it to "paint" the color on the wall.

But I can imagine other use cases for a functionality like this.

You will probably need to do it with dynamic paint, as Charles recommended, and it is possible without solving a camera motion:

You can easily set it up by tracking the wall where he is painting with a simple 4 point track, so you get 5 markers. Then, link empties to those markers, hook a plane's vertices to the wall markers and parent a cube or other object to the "painting" marker, so you can get a canvas (plane) that deforms with the footage without solving or reconstructing geometry.

Set the dynamic paint to output an image sequence of the object painting's on the plane, and then use that image sequence in the compositor as the mask, or alpha, that you need to create the effect that he is painting it.


Blender FBX/OBJ house export doesn't include interior I'm not exactly sure how to be able to render this house mode with the interior for use in Twinmotion. I can look 'inside' the house in Blender and see materials/faces/etc, but but it goes into twin motion, going into the house doesn't show the blackface of the walls etc (like no-clipping mode).

This is it in Blender:

I'm not sure how to add a .blend file here (any suggestions)? Thanks!

stphnl329 was right. I can't believe I didn't notice it, but the main exterior walls (which are hard to make out in wireframe) are just planes of no thickness. I added a solidify modifier and applied it, and all is well! Thanks!


How to change the default value of Image compression? Hello I found a little problem right now I'm working in a project using blender I bake a lot of textures but since this bakings are a lot of test I want compress at 100% why because I use a Git repository and that increases the repository size.(Of course I try to avoid binary files)

So after explain what I'm doing I'm tired of change the value every time that I open Blender.Compression value is 15% I want to change that default when I start blender

I already tried to use Ctrl+Alt+U. System Tab->save users settings that is OK with the plugins but I always have to change Compression value 15% When I open a new blender file.

Set the compression level to 100%, then press ⎈ CtrlU> Save startup file.

Note that this will save everything, including view position, objects, etc. as default.


Weight Paint only Upward Faces Can I somehow accurately only apply weight paint on faces pointing upwards?

In edit mode select the faces you want to modify and then, in weight paint mode, enable the faces or vertices selection masking button. Remember that weight is a property of a vertex relatively to a vertex group, so face normal is not taken into account.


Selecting and moving a subpart of a mesh I have a question about this tutorial. At about 17:00 min Blender Guru creates a window and then selects a door of this window and moves that door to the left. I have tried to follow him doing that (you can see the strokes he makes) but I have still questions.

He seems to select a part of this mesh (window) and then simply moves it away. How is it possible that he can just move away part of this mesh (I mean it is connected to the rest of this mesh). And he also seems to do CTRL +L, why is that ? I simply don't understand this select and move away operation.

The door is here a subpart of the window mesh object.

This subpart is defined as a part of the mesh (some vertices and faces between all the others). And this subpart is not linked to the rest of the window vertices. This is like you have here a subset of the vertices dedicated to the door.

As this subpart is so some kind of "vertices isle", he can select it by just selecting (with the mouse) one or two vertices and then use Ctrl+L because this shortcut means "select linked" or "starting from a selection, select also all the vertices linked by one or several edges to this primary selection".

Concerning the "move away" : this is the consequence of above. Inside the window object, door vertices are not linked to the other vertices. So they can be moved independently in edit mode.


Powdered sugar sprinkling? I'd like to know how to create a powdered sugar sprinkling like the one shown on top of the cake in the image below. If you could provide a picture of the node setup for a material, that'd be great. Thank you! :)

Shader Method
I used a Noise Texture with a Color Ramp set to Constant to generate a sugar sprinkle mask.

Then I mixed some noise into Generated Coordinates and separated out the Z axis.  I could then apply another Color Ramp to isolate the top of the cake.

Multiply these two masks together with a Math node and you get a mask that you can use as the Factor of a Mix Shader between your cake and sugar.  The top Color Ramp controls the size and density of spots of powdered sugar.

Particle System Method
Instead you could "model" a sugar particle by adding an icosphere.  Put it somewhere out of camera view.  Give it a suitable material for sugar.
Start a Particle System on your cake.  Set it to Hair and under Render select to Render As Object and set the Instance Object to your Icosphere.

Since we're emitting from faces you have to worry somewhat about an even distribution of faces on your object.  I didn't bother since this is just an example, and it might be useful to someone to see the consequences of it.
I've marked all the settings I changed to get this result.  (Note: Hair Length is the same thing as Normal Velocity.  In this case it is in effect a multiplier for your object scale.)

I thought maybe interpolated children would solve the problem automatically.  It does not, although it may make it easier to deal with in some cases and it provides an interesting result nonetheless.  Also beware that at default settings you'll generate 100x the number of particles on render.

If you want to limit to only a certain region, you can create a Vertex Group either through assignment or Weight Paint mode, and assign this as the Density group of the Particle System.


Issue with creating high precision Ngon faces ( screencast of the issue in action )

Trying to get a better understanding of face creation. I've got some very high detailed faces I'm trying to make that will later be used with a subdivision (multires) for animating a displacement map.

I'm nearly zoomed in 100% ... a few steps out ... and trying to create some Ngons. Most of the time it works perfectly but occasionally I will get a face that seems to ignore one of the vertices. When this happens the edges are created using the errant vertex but the face seems to skip it.

The faces are all co-planar (0 distance on the Y axis). I even selected everything and re-scaled to 0 on Y to be sure but it didn't change anything.

I've made a video showing what I'm doing. Basically trying to make sure I don't have any faces that are below a certain size near my seam. To do so I'm selecting nearby vertices and moving them to the seam edge vertices with auto-merge on. Then I'm deleting sub-optimal faces and re-creating them with the newly positioned vertices.

Take a look at the short screencast linked above to see the face being created with the strange edge. Perhaps this is just a wireframe preview bug? But I haven't seen it happen elsewhere in the model.

The precision I'm going for is sort of silly but it's one of those labor-of-love projects. I've found ways to make the ngon the way I want it to work, the video shows one workaround, but I've had most of my workaround methods fail and it becomes awfully intensive (I'm optimizing a couple thousand faces this way).

NOTE: I'm using Gooseberry with wireframe colors on a different mesh that is adjacent to the one being used. Not mentioning this because I think it is the issue (this occurs when switching to the standard distribution). Just letting folks who might be confused by seeing nearby edges in an unusual color.

It's a kind of warning that you are creating a concave quad face.

Ther's an article that explains they should be avoided.

Remember that render engine base their calculations on triangled meshes. Concave quad faces, as non planar quad faces, are not automatically splitted in Blender.

You can see how it works by adding a plane and move the vertex with fixed z till is placed inside the triangle made by the other 3 vertices


How do I fix irregular surfaces enter image description hereI already read some post related to this issue, did what they say but I still having the same problem. As you see in the picture the surface of my mesh has many irregularities (cheeks). I tried fixing quads so I did delete all the cheek area and modeled again but the irregularity still appearing, It is a rigged mesh so I don't think is a problem with doubles. Can somebody help me to fix this ?

enter image description here

I see one vertex on each cheek with 8 edges going into it, that's just bad modelling. I recommend CG Cookie's tutorial: https://vimeo.com/3835507


Is there any way to generate Inverted or taper geometry by using displacement? Is there any way to generate reversed taper geometry? In other words: I'd like to generate the geometry you can see in the following picture just by using displacement modifiers or by using nodes:

Q: Is something like this possible by using displacement? The purpose of me thinking that this is nearly impossible is because if having a larger displacement on top, how am I supposed to depict a tapering gradient bellow it visually on a map? You can not show a dim gradient bellow a bright surface on a displacement map right?
Note: This question is not specifically about cones, it is about any type of displacement where I have a bigger surface on top of a smaller surface.
For better illustration consider a plane , Subdivide it 100 times and switch to cycles rendered mode with Displacement type set to Displacement and bump. The if i create the following Node tree , i can get the following result. The node tree is finding the Length of the origin and using a color ramp to manipulate the falloff of the resulting spherical gradient and passing through a displacement map to get the final result , but how can i taper at the bottom and have a bigger surface at the top?

I write an answer as proposed to by @SHikhaMittal. Though, still not sure this is the wanted result.
As this is about "any shape", have used an image, like a decal, to drive the displacement.

The shape is colored with "wireframe" node, so that we can see the result of the displacement in term of geometry.
The nodes:

Bottom part is the decal used to drive the displacement scale. It is 0 outside of the image.
The middle line is to offset the normal around the mesh center. X and Y parts are scaled and added to the normal in order to drive this normal "outside".
Top part, the wireframe colors.

Remarks:
We can notice that the scaled and displaced part looses resolution, because we only keep a small amount of vertices and scale them.
The other answer by Bruk, using another way to do it (scaling down a larger part along a cylinder) should avoid this issue.


Displacement Stretched I have a simple displacement setup as follows:

When I apply this same material to two differently sized objects, the displacement seems stretched on the larger object:

Scale has been applied (Ctrl+A).

Is there a way to make the displacement the same 'scale' on objects of any size?

Here is a link to the sample .blend file:

https://1drv.ms/u/s!AqKxXPZzafVQla8hzonVpxSvpK9jwQ

This was created using Blender 2.8 beta.

To have consistent scale, create an Empty in your scene and make it control the texture scale.

Create an Empty
Edit your material by adding an Input>Texture Coordinate, using the Object socket and linking it to the Empty in the "Object" dropdown

Scale (, Rotate, Move) the Empty to make the feature the size you want. This will apply in a coherent way to both objects that share that material.

Big Empty

Small Empty

Note: if your object is going to be moved in animation, and you want the texture to stick to it, then you should either (1) parent the empty to it, (2) consider following Mark Jackson's answer (although you will need to adjust the proportions of the texture manually), or (3) use an UV map.


Robot arm move a box I'm doing a simple robot arm that turns the arms around and do different movements. But I can't figure out how I should do if the robot should pick up something like a small box?

Should the box be connected in some way to the armature to be able to follow the  movements of the arms? Perhaps I want the robot to pick up the box after some time and not from the beginning, how do I connect it then or what is the best approach?

To do an animation of this (without using Rigid Body physics) you would simply need to constrain the Box (object being acted upon) to the Clamp of the Robot.
The problem happens when you sit it back down.  You must somehow apply the new transformation but as far as I know, you can't animate Apply (I haven't found a way).

The solution is somewhat fiddly and inelegant and there may be a better way (apart from rigid body), but it works.

1.) Add a Copy Transform Constraint to the Box and select the Clamp as the Object of influence.

2.) For this demo, I set the Clamp's Origin to the location of where I want the Box to be when "clamped".  This is basic so I won't go into detail.  (Ctrl + Shift + Alt + C)

3.) I animated the Clamp to descend onto the box to that point (Shift+S

4.) (gif anim frame 49) At this same frame, keyframe the Constraint Influence to be 0.00 by pressing I.  You could also keyframe the "Eyeball" instead (enable/disable constraint).

5.) (gif anim frame 50) On the very next frame, keyframe an Influence of 1.00.

6.) (gif anim frame 202) Animate the Clamp however you want and sit the box back down, keyframe the Influence to 1.00 on this frame.  Also, with the box selected, press I and select LocRot.

7.) (gif anim frame 203) On the very next frame, select the box, then Shift Select the Clamp.  Right-Click on both the Rotation and Location Transform menus and choose "Copy All to Selected".  Select the box only in 3D View and press I and select LocRot.  Keyframe the Influence back to 0.00.

This sounds more complicated than it is, I just wanted to get everything in here in case you weren't clear on something.


Access operator's property with python Is it possible to access the property of an operator (such as the filepath to the append operator) by python ?

Passing properties to an operator, here's a small example (see the test call towards the end). This snippet is an elaboration on TextEditor > Templates > Python > Operator Simple

import bpy

class SomeOperator(bpy.types.Operator):
    """Tooltip"""
    bl_idname = "object.some_operator"
    bl_label = "Simple Object Operator"

    property_one = bpy.props.StringProperty(default='state one')
    property_two = bpy.props.StringProperty(default='state two')

    @classmethod
    def poll(cls, context):
        return True

    def execute(self, context):
        print(self.property_one)
        print(self.property_two)
        return {'FINISHED'}

def register():
    bpy.utils.register_class(SomeOperator)

def unregister():
    bpy.utils.unregister_class(SomeOperator)

if __name__ == "__main__":
    register()

    # test call
    bpy.ops.object.some_operator(property_one='woop_one', property_two='woop_two')

if you want to call such an operator from a layout element..

# if you want to pass a single property
row.operator('object.some_operator').property_one = 'some_new_value'

# if you want to pass multiple properties
some_op = row.operator('object.some_operator')
some_op.property_one = 'some new value one'
some_op.property_two = 'some new value two'

Autocomplete

If you don't know the name of the properties, then you can use the Python console's autocomplete.

In this example hit ctrl+space after the parenthesis ( , here you see lines is the only property you can set.

Documentation

Another resource is the current api docs use the search feature, type in for example bpy.ops.text.scroll and it will show the signature.

In the case of WM_OT_append you should be looking for bpy.ops.wm.append.

Tooltips

Use the tooltip that appears by default upon hovering of menu items / buttons:


How to join objects with Python? I try to do this:

bpy.ops.object.select_all()
bpy.ops.object.join()

in my script. It selects all the stuff like CtrlA but fails on join() (CtrlJ) with the following error message:

  Traceback (most recent call last):   File "", line 1,
  in    File "C:\Program Files\Blender
  Foundation\Blender\2.71\scripts\modules\bpy\ops.py", line 188, in
  __ call __
      ret = op_call(self.idname_py(), None, kw) RuntimeError: Operator bpy.ops.object.join.poll() failed, context is incorrect

the message is from console.

How can I make this work?
CtrlA, CtrlJ actually works.

If you don't want to change the real selection states, you may wanna use an override:

import bpy

scene = bpy.context.scene

obs = []
for ob in scene.objects:
    # whatever objects you want to join...
    if ob.type == 'MESH':
        obs.append(ob)

ctx = bpy.context.copy()

# one of the objects to join
ctx['active_object'] = obs[0]

ctx['selected_objects'] = obs
# In Blender 2.8x this needs to be the following instead:
#ctx['selected_editable_objects'] = obs

# We need the scene bases as well for joining.
# Remove this line in Blender >= 2.80!
ctx['selected_editable_bases'] = [scene.object_bases[ob.name] for ob in obs]

bpy.ops.object.join(ctx)