text:
How do I rotate a face around an axis in normal orientation in Python?
I have a set of vertices for a BMFace that I'm trying to rotate around the x-axis but in the face's normal orientation. Currently I'm doing:
c = face.calc_center_median()
T = Matrix.Translation(-c)
rot_angle = 0.25
rot_axis = (1, 0, 0)
bmesh.ops.rotate(
    bm,
    space=T,
    matrix=Matrix.Rotation(rot_angle, 4, rot_axis),
    verts=face.verts
)

My guess is that I can get the normal x-axis through face.normal but I'm not sure what to do next or how to best formulate the question to learn more. There are an infinite number of possible x-axes orthogonal to face.normal, aren't there?

After some reading I managed a solution, but I'm not sure how robust it is:
tangent = face.calc_tangent_edge_pair()
rot_axis = -face.normal.cross(tangent)

The tangent is one of the other normal axes and from that the last axis is calculated as its cross product with the face's normal.
This seems dependent on which edges are the longest (the documentation for BMFace.calc_tangent_edge_pair says: "Return face tangent based on the two longest disconnected edges."), so I imagine there's a better way to approach this!


text:
Inconsistency in Python Interface for Scaling and Applying Transform on Empty Object
In Blender 2.8.x, using the python interface one cannot scale an empty object and then apply the transform using apply_tranform similar to mesh objects. Does anyone know a way around this?
The issue can be produced as follows:
bpy.ops.object.empty_add(type='PLAIN_AXES')
empty_obj_handle = D.objects['Empty']
# Pick a random scale
# The command below results in a scaled object
empty_obj_handle.scale = (0.1,0.1,0.1)
# Now applying the following command removes the scaling
bpy.ops.object.transform_apply(scale=True)

The empty object can still be scaled and the transform applied to the scaled object using the 'CTRL+A' + 'Scale' GUI hence the inconsistency.

Good remark/question!

source: Stack Exchange

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

sort: votes


text:
Object referenced by PointerProperty in Python can not be deleted properly
I am trying to replicate the functionality of Object Parent using the dropper select tool in Python (an image is attached for what exactly am I trying to replicate).:

For this purpose, I am using the PointerProperty to get a pointer to the object. Most of the functionalities work as expected, similar to the implementation above. However, if I delete the object (either using the keyboard shortcuts or the python method), it disappears from the 3D view but it is still present in bpy.data.objects. Moreover, the PointerProperty does not clear the object field as is the case with the original object parent field. I have tested this in Blender 2.79 and 2.81 with similar results. Any suggestions would be appreciated.
This is the code I am using.
import bpy
bl_info = {
    "name": "Pointer Property Test",
    "author": "Mr. Potato",
    "version": (0, 1),
    "blender": (2, 79, 0)
}

class PT_test_constraint(bpy.types.Panel):
    """Add Rigid Body Properties"""
    bl_label = "TEST PROPERTIES"
    bl_idname = "addon.test_constraint"
    bl_space_type = 'PROPERTIES'
    bl_region_type = 'WINDOW'
    bl_context= "physics"

    bpy.types.Object.test_constraint_parent = bpy.props.PointerProperty(name="Parent", type=bpy.types.Object)

    def draw(self, context):

        layout = self.layout
        col = layout.column()
        col.prop_search(context.object, "test_constraint_parent", context.scene, "objects")

def register():
    from bpy.utils import register_class
    register_class(PT_test_constraint)

def unregister():
    from bpy.utils import unregister_class
    unregister_class(PT_test_constraint)

if __name__ == "__main__":
    register()
    #unregister()

Because the object has a user (the object it's a property of)  it is only unlinked from the scene.  If you bpy.data.objects.remove(ob) the object it will also be gone from the pointer prop.  Might find this useful https://blender.stackexchange.com/a/101301/15543.   Also recommend declaring properties in the register method, rather than in panel class.

Thanks for the answer. Based on your suggestion and the link that you posted, what I think is appropriate is to check if the parent_object (selected by the PointerProperty) has less than 2 users (as if it has less than 2 users, it would mean that someone deleted it from the scene graph using the keyboard delete key). If so, I should call bpy.data.objects.remove(parent_object) in the Labels poll() method so that it is safely removed from the PointerProperty and bpy.data.objects. Does this seem reasonable?

Not sure about that, worth a go I suppose. Speculating a bit here, parent is a special case that is quite likely dealt with by the depsgraph when the object is unlinked from scene or deleted.  A getter / setter approach on the property could be the go, setting to None if the pointer is not in the scene.

Based on the suggestion by @batFinger, I realized that if I delete the object using the keyboard shortcut or using the Python console, it is unlinked from the scene and its reference count decreases by 1. Since the pointer property still has a reference to the object, it is not removed from bpy.data.objects. Therefore, I check in my Panel draw() function (which updates automatically) if the desired object is present in the scene as follows:
if context.scene.objects.get(desired_object.name) == None:
# That means that the object has been deleted from the
# scene graph, therefore remove it explicitly
    bpy.data.objects.remove(desired_obj)

This lets me reproduce the functionality inheret to the Blender when dealing with PointerProperty Objects as mentioned in my question.

The draw method is not really the place for this... suprized it works.  Usually trying to alter data in draw produces an error.

I agree, but so far it seems to work in Blender 2.79 and 2.81. Does deleting an object generates an event? and if so, can a method be bound to that event.

You may want to use an depsgraph_update_post app handler.

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


text:
How can I order the vertex index?
I'm new around here. I wanted to ask if there is any way to order the vertex index in this way?

see https://blender.stackexchange.com/questions/36577/how-are-vertex-indices-determined

Bmesh version

Here is a bmesh version of @3fingeredfrog's answer using method suggested here https://blender.stackexchange.com/a/36619/15543
Orders based on distance from scene cursor.
import bpy
import bmesh

context = bpy.context
scene = context.scene
ob = context.edit_object
mw = ob.matrix_world
cloc = mw.inverted() @ scene.cursor.location
me = ob.data

bm = bmesh.from_edit_mesh(me)
#bm.verts.ensure_lookup_table()
verts = sorted(bm.verts, key=lambda v: (v.co - cloc).length)

for i, v in enumerate(verts):
    v.index = i
bm.verts.sort()
bmesh.update_edit_mesh(me)

Could maually select all vertices in order (one by one) and retrieve from the select history
verts = [e for e in bm.select_history if isinstance(e, bmesh.types.BMVert)]

The order in question appears to be that next is furthest of all the connected verts if not visited.

In this particular case, yes, by ordering the index number of each vertex relative to its distance from the 3D cursor.
1: From the Viewport Overlays menu > Developer > enable the Indices option. The index number of each selected vertex will now be displayed in blue.

2: Position the 3D Cursor so that it is closest to "v1" and "v2" is the next closest ..........
3: In Edit mode and with the vertices selected: open the Mesh menu > Sort Elements > choose the Cursor Distance option.
now v1=0 v2=1 v3=2 v4=3 etc

Good answer, but the questions tag says scripting. Do you have any input on a scripting approach? E.g. how to position the 3D Cursor and call that operation with python?

oppps, I missed that @Dark -Z was looking for a scripting solution and have no idea how to do that with python.

thanks for the information, I work by doing it manually but do not know of the existence of any python script that does this job?

I need a script because there are many mesh that I need to order the index


text:
Transparent material from 2.79 is solid in 2.82
I just switched from 2.79 to 2.82 and I face 2 problems. In 2.79 I could simply select a material to be transparent and set the parameters (alpha etc.). I do not find these options in the 2.82 materials menu. Are they gone? Even worse: When I import old files from 2.79 formerly transparent materials are now solid. Do I have to switch back to the old version? I only need simple transparency, no imported images or more complex stuff.

Cycles still works the same.
But in Eevee, you need to enable transparency per material.
Set Blend Mode to Alpha Blend in the material settings.


text:
On object cannot be moved along X
There is a certain object which, when selected, can only be moved along a plane:

Previously, it could be moved along all three axes. It can still be rotated and scaled using three dimensions. When I select a group of objects that can normally be moved along all three axes and then add this object to the group, the X arrow disappears as well.
When I modify its X location directly in the table, it moves. But if I select a group which includes this object and then change the X location, all objects move except for this one.

Make sure that you haven't locked its Location on X:


text:
The same UI POV in all modes
In Blender 3, each mode (Modelling, Geometry Nodes etc.) has its individual UI POV (or how the user sees the scene in the graphical interface, I do not know how it is called in Blender). For example, I change the view to the currently modified object, then I change the mode and Blender shows some other object which I do not edit at the moment.
Is this possible to have a unified POV for all modes? Or alternately, can I edit Geometry Nodes in the Modelling mode?

Hi :). These are called workspaces. They're just a predefined set of editors, which you can change. So yes, you can open a Geometry Nodes Editor in a Modeling workspace.

TL;DNR: Yes you can edit Geometry Nodes in the Modeling workspace.  No you can't sync the same editor in two different workspaces so that both workspaces always show the same thing.
The manual section Window System Introduction is a good starting point for learning the names of the various parts of the Blender User Interface.
The simplest form of Blender has a single window that has a Top Bar that contains the various master menus and a collection of tabs for Workspaces.
To answer your first question, yes, you can change the layout of a given workspace.  A Workspace is subdivided into areas. As you can see from the area manual section, you can change the layout; adding or removing areas, and moving the borders to make one area larger and another smaller.  You can even split an area into two new areas or join two areas into a single area.
You can put any editor you want into a workspace by selecting it from the Editor Type menu, so yes you can have a Geometry Node Editor in the same workspace as a 3D Viewport editor.
What you can't do, is have an instance of an editor in one workspace exactly match an instance of the same editor in another workspace.  The editor windows are separate from each other and (with the exception of the timeline indicator) there is no synchronizing.


text:
Select all objects in a collection
I have several objects in a collection. Some only carve others and should always be invisible. I want to select all objects in a collection, so that I can move it without changing its internal structure. Yet Collection -> Select objects selects only the visible ones. It makes no sense to me - the carvings should move together with the carved.
So I need to make temporarily visible all invisible objects one by one, then select objects, then move the collection, then deselect the objects which should be invisible. Time consuming and error prone.
Blender has multiple methods of choosing object visibility, eye, screen, camera. I tried different combinations, and it seems that both eye and camera exclude an object from "select in collection". Any method of having an object which is invisible on the screen and in the rendering, but can be selected as a member of a collection? Doesn't "select all in a collection" sound like a basic operation"?

Does this answer your question? Hi! Is there the way to select all the objects inside collection using shortcut (Blender 2.8)?

@brockmann select one -> shift G -> collection seems to behave in the same way.

I think this is a question where it's worth stepping back and asking what the real problem is.  Here, you want two things: you want objects to not be visible (probably, to prevent them from obscuring your view) and you also want to be able to move objects.
I make a lot of non-rendering objects.  Rather than hiding these objects, I set their display to wireframe, in properties/object/viewport display:

These objects are still selectable, but they're difficult to select in the 3D viewport-- you have to click close to the actual edges.  They're still easily enough selected via operations like select all or select similar.  They won't show up in a viewport that has overlays disabled (and I usually work with two 3D viewports open, one with overlays disabled.)  That's good enough for a viewport render.  They'll still render in a "real" render, which is probably a problem, but it's an easily fixed problem.  We can disable their visibility in renders in a number of ways.  One way is to disable show in "renders" in properties/object/visibility/show in:

Once we do those two things, we have a convenient, non-rendering object that won't get in the way, that's easily hidden when necessary via clicking on overlays, and that we can still easily select and edit.

You can select the first object in the collection and then go down to the last object and Shift select, this will select all objects that are between the two selected ones(even if their visibillity is set to off).

It does selects objects, but at least in one case, when I try to move them, only the visible ones move together. If I make an already selected object visible and try to move the selected objects again, then the object just made visible moves as well. So there is kind-of two-level selection in Blender?

Is is particularly visible when I delete objects in a selection made that way: all objects disappear. Now I undo, move objects in the same selection and only the visible ones actually move.

The BlenderBim add on https://blenderbim.org/ adds the functionality to right click on a collection and select all.


text:
Angle measurement shows only integer values, is it possible to increase the precision
In Blender 2.92, the measure tool shows distances to the precision of 6 digits after the decimal point, but only integer angle values. This question suggests that previous versions showed two digits after the decimal point.
The linked question has three answers:

copy and paste that value, but I do not know how it is supposed to work;

use N shortcut then "mesh display", but in my version nothing like that shows;

use an extension;

use a script.

Is there a simple way of increasing the precision to at least one digit after the decimal point?

The shipped add-on MeasureIt Tools allows you to set precision:

and gives you a nicer display


text:
Precise, concise edge length measurement using a decimal point
I switched on edge length measurements. For a length of e.g. 1.054 I get a value "1m 5cm". It lacks precision, takes place and is hard to read. Any way of getting a precise value with a decimal point and preferably no unit lengths at all?

you can change your units here:

if you set Unit System to none you will get this:


text:
Rotation in local coordinate system: angle edition gives strange results
If I rotate an object in its local coordinate system, Blender behaves in a way which I do not understand.
Example. Let there be an object:

I rotate it with a mouse, by dragging the red ring:

Now I want to make a small correction by editing the text field Rotate/Angle in the dialog at the bottom left. As such edition previously gave unpredictable results, just to test it out, I select that text field and confirm with enter exactly the same value as was there before. I would expect the mesh to stay in place, but it is not the case:

Again, just to test, I press Ctrl-Z to undo and the mesh state goes back to the first picture, skipping the second step as if it never existed.
I do often such small corrections and it works, but not in this specific case of rotation in local coordinates. Why?

This is a known bug.

I suspected that it is a bug, but Blender has so many switches that I also asked myself if I did not inadvertently toggle something which resulted in such a counter-intuitive behaviour.


text:
Find angles between list of sorted vertices using vertex.co.angle()
I am trying to use the technique described here Python: Calculate angle between vertices to determine the angles between a list of vertices that is sorted left to right on the x axis
        mylen2 = len(vertices)

        if(mylen2 > 1):
            a1 = vertices[mylen2-1].co.angle(vertices[mylen2-2].co)

            if a1 > pi * 0.5:
                a1 = pi - a1
            print("{:.2f} degrees".format(degrees(a1)))

My output looks like this:

but my vertices are like this:

I can't imagine these angles are all less than 10 degrees especially since many appear to be on a 45 degree angle.
How can I correctly find the angles for a list of vertices in degrees?

Vert co as a vector is from origin point.

Diagram where the red ico is the origin of a mesh and the other icos are the vertices.
Question code is calculating the angle designated as alpha above between the vectors defined by the  two vertex coordinates.
It appears you are after (beta) the angle between the vector made from two verts
vec = verts[i].co - verts[i - 1].co

and the x axis Vector((1, 0, 0)).angle(vec) or if the points do not all lie on same XZ plane, the projection of vec onto the XY plane containing point    verts[i - 1].co.
Example from python console, consider vec = Vector((1, 1, 1)) ie this is the result when subtracting i-1th vert from ith. Meaning if you travel (1, 1, 1) from vert[i-1] you will be at the location of vert[i]
>>> vec = Vector((1, 1, 1))
>>> x_axis = Vector((1, 0, 0))

Angle between 3d vectors
>>> degrees(x_axis.angle(vec))
54.735612876297274

To project as 2d vectors onto Y=constant plane, can get the signed angle between the 2d vectors ignoring y.
>>> degrees(x_axis.xz.angle_signed(vec.xz))
-45.00000125223908

the vertices are all on y=0

Okay. I get that co gets the angle from 0,0 but how do I get the angle between two of the vertices?

There is no angle between two points. without some other reference vector. Have explained what you are calculating in question (alpha) and how to get what I assume you are after the angle beta.  Can't go north west from point A to point B without having some reference of what north and west is.  Just looked at link posted in question, also points out that a reference vector is required.

or to put this another way, have used grease pencil to demonstrate the angles alpha and beta. Edit your question with diagram of expected  "angle between two vertices".

yes beta. The angle between the two points.

if co.angle() returns the angle of vertex2 relative to 0,0, I assume I have to subtract vertex1 from vertex2 then run co.angle on the result to get the angle between?

Please read answers (above and https://blender.stackexchange.com/questions/34926/python-calculate-angle-between-vertices) mine explains  how to get the beta angle shown using the X axis as arbitrary reference vector.. The latter uses the Z axis as the arbitray "north" vector.  Points do not have an angle between them.


text:
edges.new - Edges Not Adding Correctly (black not solid orange)
I'm using a python script to create edges.
For some reason, my script is recognizing some edges, displayed in solid orange.
Others are not recognized the same and are displayed in black.
(see image)

When I manually select two of the verticies on a black line and hit f the edge is added correctly and displays orange. This is specifically a problem because I cannot face-->fill the shape until all the edges are displaying as orange.
I'm adding the edges like this:

class Graphics:

    def __init__(self,bm):

    def drawLoop(self, bm, lines):
        for i in lines:
            self.drawLine(bm, i.p1tuple(),i.p2tuple())

    def drawLine(self, bm, tup1, tup2):
        v1 = bm.verts.new(tup1)
        v2 = bm.verts.new(tup2)
        bm.edges.new((v1, v2))

My Main is like this:
import bpy
import bmesh
import sys

obj = bpy.context.object
me = obj.data
bm = bmesh.from_edit_mesh(me)

graphics = Graphics(bm)

bmesh.update_edit_mesh(obj.data)

Perhaps you're adding duplicate vertices, where the v2 of one edge is also the v1 of the next one?

@RobertGützkow I thought that might be possible. Though I'm not sure how to test for it or how to fix it. I've tried removing doubles to no effect. I should also mention that the parts of the shape are built at different points in the program. If that makes a difference?

That can be overlapping meshes. But the provided code can't run properly and you provide too few information about the input lines.

Look like you are creating 2 new vertices per line. Unless I am mistaken... you are creating disjointed segments. Instead, shouldn't you just create a new vertex, then the new edge between the previous vertex and the new one?

@Bruno I think you've got it. Rookie mistake, really.

@Bruno Fixed it. If you put this in an answer I will give you the bounty.

Roger that, thx!

Look like you are creating 2 new vertices per line, that's creating disjointed segments. Instead, just create a new vertex, then the new edge between the previous vertex and the new one, etc...


text:
How to distribute collection on shader displaced object?
My well subdivided plane Object has a shader with a nice displacement.  My GN distribute collection as instances on points does not follow the visible geometry, instead it follows the level plane.  How do I get the GNs distributed objects to follow the visible geometry in Viewport Shading 3dView?

Well, if the displacement is done in a shader material, the answer is quite simple: you cannot distribute the GN objects on the visible geometry. There is a reason why shader displacement is only showing in rendered view: shaders are calculated at last before rendering. Modifiers to which Geometry Nodes belong are calculated before the shader, so at the time the result is calculated the displacement does not exist. You'll need an actually displaced mesh or a Displace modifier for that (and if the Displace modifier is on the GN object itself, it needs to be before the GN modifier.


text:
4.1.1 Adding gobo to area light does not work
I am trying to add a noise gobo to an area light as shown in many different tutorials.  However my noise / color ramp do not seem to have any effect not matter how much I adjust.  I've experimented with different values such as a wave and image texture as well as using math to increase/decrease the values going into the color ramp and nothing changes or works.

I found this blender thread that seems to be related but I am not sure if this will help me or how to utilize the info since I have 4.1.1 is sounds like I'd not have that issue.  https://projects.blender.org/blender/blender/issues/121174 - I tired the Geometry nodes 'Incoming' socket too and noted that my Area light does not seem to have a 'soft falloff' control.  It almost looks like the gobo might be working with the incoming socket but I cannot adjust the ramp enough to get the desired deep contrast.  This is why I tried to adjust the values with a math node (add and/or multiply/divide)
My basic question is "How can I add a simple ramp adjustable noise gobo to my area light"?  The normal way is not working for me.  Am I missing something obvious?

I downloaded 4.2 and switched from an Area light to a spot light and that seemed to make a difference.  The spot light has the 'soft falloff' control.  I am still hoping for more clarification on this topic

Making a gobo with an area light requires only a few things:

a texture. It could be an image, or procedurally generated. Since it's basically a plane emitting light, the default texture coordinates (UV) already works out of the box.
Light beam spread MUST be zero. Even 2⁰ is enough to make the projected texture significantly blurry.
Use the light's size to control the size/ratio of the projected texture.

Doing any color modification on the texture is done the same way as usual, by adding nodes after the texture node. I.E. to control the color intensity of my texture, I could use a Color Ramp node:

To control the feathering of the texture as it goes to the edge of the light's projection area, this however requires a bit more elbow grease. I like to use the UV input, Separate the X and Y channels, use a Math: Ping-Pong node, a map range to control the offset and the gradient of the feathering, then multiply both channels and multiply the result to the texture:

Which of course can be turned into a nodegroup for easier (re)usage:


text:
Landscape ANT is gone
After dealing with an add on named ANT Landscape, present but not operational, meaning I could see it and click on it but nothing would happen, and today it was gone, not totally because in the Preference section, and add-ons, ANT Landscape is there and selected but that's it.
What am I missing? Oh yeah! I'm not a stable genius.
Thank you for any help you could provide me with.

You mean when you go to add it, (SHIFT+A > Mesh > Landscape), nothing happens?

SHIFT+A .> MEsh > ?Landscape is no longer there. I'm gonna uninstall and reinstall.Thanks!


text:
Polygon Material_index Animation
I would like to change polygon material during an animation with the following code.
However, the animation does not show the color changes of the polygons.
What is going wrong, isn't it possible to animate polygon material changes?
What is the best solution to do it with Python?
frame_count = 1

for polygon in polygons:

    bpy.context.scene.frame_set(frame_count)
    polygon.material_index = 1
    polygon.keyframe_insert(data_path='material_index', index = -1)

    frame_count += 10

Hello, could you add more information about what your code snippet is supposed to achieve ? Currently, you are trying to add a single keyframe per polygon at a 10 frame interval between each polygon until there is no more polygon left to iterate

We have a path over a surface, every polygon of the surface that we visited should change its color.
We are using to visualize some software algorithms on surfaces.

Random keyframing polygon material indices

Code below run on a default cone with 4 materials of colour: red, green, blue, yellow.

Can set the frame in keyframe insert

All polygons are given material index 0 at frame 1

At the frame 2 times the polygon index plus 10 the polygon changes to a random choice of material slots with material.

Example script.
import bpy
from random import choice
context = bpy.context
ob = context.object
me = ob.data

choices = [i for i, s in enumerate(ob.material_slots)
        if s.material]

for p in me.polygons:
    p.material_index = 0
    p.keyframe_insert("material_index", frame=1)
    p.material_index = choice(choices)
    p.keyframe_insert("material_index", frame=2 * p.index + 10)

Using Drivers

It is a low level version of dynamic painting

In which case here is an example of using a driver instead of keyframing an fcurve.
Example below selects face index based on integer global distance of face center to emtpy.  Have left in test driver method with  test prints
The world matrices of the empty and the mesh object are added as driver variables, and passed to driver method by way of locals.
The image above is on a 16 x 16 grid, takes a while to run.  On my system a 100 x 100 grid works but takes a while and can get unresponsive.
Select the mesh object and run script.
import bpy

context = bpy.context
ob = context.object
me = ob.data

bpy.ops.object.empty_add()
mt = context.object

def add_driver(face):
    face.driver_remove("material_index")
    fcurve = face.driver_add("material_index")

    driver = fcurve.driver
    driver.use_self = True
    driver.expression = "x(self, locals())"
    var = driver.variables.new()
    var.name = "mw"
    var.targets[0].id = ob
    var.targets[0].data_path = "matrix_world"

    var = driver.variables.new()
    var.name = "emw"
    var.targets[0].id = mt
    var.targets[0].data_path = "matrix_world"

def x(self, locals):
    print(self)
    print(locals)
    mw = locals["mw"]
    emw = locals["emw"]
    d = (mw @ self.center - emw.translation).length
    return min(int(d), 5)

bpy.app.driver_namespace["x"] = x

for p in me.polygons:
    add_driver(p)

Related
This one randomly sets color of faces of a modified (eg subsurf) mesh using a frame change handler.
https://blender.stackexchange.com/a/183440/15543

@Mirko cheers.  Have never ever seen, nor tried this.. thanks for the heads up! Opens numerous possibilities.

it is a low level version of dynamic painting and very handy, thanks for your support


text:
Bones/Armature do not show up once I change the view
I am very new to Blender and I am attempting to create a humanoid for a gaming program. Currently, I am trying to animate my character and I have my armature set up on the front of my humanoid. Unfortunately, if I try to change the view of my humanoid, the bones disappear immediately. How do I fix this?
This is the first view with the bones displayed
The bones completely disappear when I change the view

are you sure that the armature is not far away on the right or on the left? Try an alt G to see if it doesn't come back to the center...

Ahh I'm such an idiot. Looks like the bones were just really far away lol. Thank you so much!


text:
ID Mask by Pass Index in bpy
New to Blender, and the documentation for bpy is throwing me for a few loops. I got a setup in the compositing layer working for my desired goal as shown:

This renders an image and a color-coded mask for each of the three unique pass_index marked objects (below), and am trying to automate this through a bpy script as there are many variations I'll need to render.

Each object can be given a pass index in bpy via e.g. bpy.data.objects['foo'].pass_index = bar, but I'm having trouble figuring out how to separate each layer(?) via pass index as the compositing nodes do. Simple camera manipulations and the like are straightforward (I have a script that can import the stl, setup camera/lighting as required, and produce images like the left one above), but I'm lacking the terminology to search the right question or understand the documentation- and recent changes between 2.7x and 2.8x make a number of older guides very difficult to understand...
Related would be the steps of adding a color and recombining to form a single image as shown in the compositing layer, but small steps first. Any help would be appreciated, thank you!

Using ID Masks for compositing is a very bad idea. They will cause serious problems with the edges if used for compositing compared to alternatives. Consider Cryptomatte instead. That's a way better solution in vast majority of cases.

In the days when Cryptomatte was not around, what was the right way and purpose to use ID masks in blender?

Specific answer for the task at hand (image segmentation) is given by the bpycv module. This isn't the same as a general compositor -> bpy solution, but posting here in case someone else also happens to (somehow) miss bpycv, yet find this post.


text:
How do I parent a bone to another bone for an imported model?
I have an imported character model where the sword is floating near the ground and I'm trying to get it to be in the correct place near the hand.
There is already a bone on the handle of the sword which is called sword_1 and it has a dashed black line to another bone which cannot be selected and doesn't seem to have a name (see picture).
There is another bone called weapon_root which is exactly where the weapon needs to be, near the end of the dashed black line, but I don't know how to move the sword there.
I have tried to make the weapon_root the parent of sword_1, but it didn't move the sword at all and it didn't seem to do anything because in the bone hierarchy they were still at the same level.
What should I do to get the sword_1 bone to follow the weapon_root bone origin?

Hello, maybe share your file: https://blend-exchange.giantcowfilms.com/

The dotted black line is called a relationship line, and it reveals that some kind of connection, either a parenting connection or a constraint connection, already exists between Sword1 and whatever this unnamed bone is. In either case, you will probably want to break this connection and start over. With the Sword1 bone selected, go to the Constraints tab in the Properties Panel, to the right of your 3D View, and check whether anything shows up. The relationship line is probably coming from something that will be found here. The other place you can check, but seems less likely, is the Object tab (not Object Data tab), and look under the Relations section, to see if the bone has a parent. If you found any connections, remove them. If you found none, then select the whole armature in Object Mode, and then tab into Edit Mode, then select the Sword1 bone, press Alt + p, and choose Clear Parent. Now your Sword1 bone should still be part of the armature, but shouldn't move with any part of it during posing. Go into Pose Mode, and move the Sword1 bone to the hand position. It might be a good idea to make sure the armature is in its rest pose before doing this, which can be activated in the Object Data tab, under the Skeleton section, where you'll see two buttons, Pose Position, and Rest Position. Choose Rest Position to see the rest pose. Once you've activated the Rest Position, however, you can't move any bones until you return to the Pose Position. So after activating the Rest Postion, press Ctrl + a and from the Apply menu, choose Apply Pose as Rest Pose. Now return to the Pose Position. You shouldn't have to do this again. It's a kind of calibration effort to ensure that you're working from the rest pose before adding constraints. If you add constraints without being in the rest pose first, weird things can happen.
Finally, while in Pose Mode, select Sword1 and create a Child Of constraint for it, and point this constraint to the hand IK target bone as the constraint's target. You will want to press the Clear Inverse button after creating the constraint to get the sword to remain where you placed it. It should follow the hand now when moving the IK target, and by keyframing the influence slider for the constraint, the sword can be released by the hand, or retrieved by it, any time you want.


text:
Export 3D text for threeJS
Blender v2.82: I have three models, all 3D text converted to mesh with colours and material added.  I want to export these 3 models for use in a reactJS application using threeJS.
I am not sure of the process here.  Do I have to unwrap the UV before exporting?
I reference the model in the code here:
const { nodes } = useLoader(GLTFLoader, "models/1_BigW5-Wmesh.glb");
The files are exported as .glb - will they still work with the threeJS renderer?
There are many demos of this but all seem to use cubes and spheres, not an imported model...

Select the text open search menu (Space, F3, depending on your settings) type in convert, choose Convert to -> to mesh. You won't be able to change the text in Three, for that you'd be much better off creating the text in Three.js.

You can test the GLB models in a viewer like https://gltf-viewer.donmccurdy.com/ — if they work there, they e exported correctly and should work in threejs. You only need UV unwrapping if the models have textures.


text:
Making sense ot the 3D View and aligning and rotating objects by specific values
I am trying to line up a camera and a mesh in the 3D viewport.  I am having LOTS of problems.
a) I have a green line - I assume this is the X axis, though it is not labelled, same for the blue line. How do I see all three axes?
b) I set the cursor to world origin and then set my mesh to cursor, but the mesh seems to just go wherever it wants to go - and certainly not to the cursor.
c) is there a trick to navigate around the 3D space without it turning upside down or moving in an unpredictable manner?  How can I even tell if it has turned upside down?  Is there any way to move the view in a single axis at a time?  I am just usinhg my Mac trackpad with 2 fingers but it drives me crazy.
d) after selecting object I noted that the Y scale was slightly different - setting it back to 1 (same as X and Z scale caused the model to disappear altogether - I never found it again...
e) I thought that having a collection including lamp and camera might be causing Blender to snap the collection rather than just the mesh - but I moved the mesh out of the collection and it made no difference.
Really, this is driving me nuts!
f) Setting the mesh origin to cursor evidently does not move the mesh to the cursor - so how do I move the mesh itself so that it is sitting EXACTLY on all three axes?

First off, red is X axis, green is Y, Blue is Z (up, down). Secondly, I'm not sure about all the rest of the issues you're having navigating the 3d viewport, but I would HIGHLY suggest using a mouse (there are many decent usb compatible mice you can get for well under $20). It will make your life a whole lot easier. Lastly, to center an object in the "middle" of the X,Y,Z axis - in object mode press SHIFT + S > Cursor to World Origin, then select your object, SHIFT + S > Selection to Cursor.

If your object is going somewhere "on it's own", it's likely that you have offset it from it's local origin in edit mode  For example: I make a cube at world origin (0,0,0) - I enter edit mode, select the whole cube and move it 20 units along the x axis - if I do this, in object mode the cube will still be at 0,0,0, even though the cube is 20 units away from the center. This will however be shown in edit mode. This is the difference between local and global offsets. You can see the difference by pressing N and looking at your object's coordinates in both object and edit mode.

Thanks mate.  I did evebtually work out how to move the mesh once - thereafter it wouldn't move at all - I had to shut down and open a new blender window and reimport the model.
I still can't align the camera to an axis - there are many ways to move the camera but I will be rotating three models and I need the camera to be perfectly aligned on the X and Y axes and I can't find any way to do that...
I used a 3 button mouse before, but it drove me crazy just the same... :-(
I never get the Y axis displayed !

dI solved this issue by selecting the camera and moving it to the cursor at world origin.  Then with the camera view open in another window I was able to move the camera along the X and Y axes until the model came into view (upside down!) and then rotate the camera until the model was the right way up - using the rotation properties box to specify the exact rotations - 90 / 180 / 180.
The Y axis alignment was done by eye - I could not find any way to centre the camera exactly on the centre of the model.
It will have to do...


text:
Perspective Camera does not change view when moved
I have a perspective camera, aligned with the model on the X Y Z axis but moved some distance away from the model in an attempt to fit the whole model in the camera view.  But moving the camera does not change anything.
Also, I have a lamp which is not intense enough to show the model properly but increasing the luminance makes no difference.
What is going on here?

Ok, I wasn't being aggressive enough with the luminance.  I increased the power setting to 5000 and that worked.
Ditto with the camera - I moved it a long way back and the model image then fitted in the camera window.
It would help if Blender provided a range for these settings - you might expect to double the luminance to get a better view, but not to increase it 5,000 fold!

Most likely you are dealing with a model that is huge, unfortunatelty you provide no information whatsoever about your scene. It is recommended to create objects in real world scale. It makes sense that lights that are too distant need to be way brighter than usual.

Its not a huge scale.  It is real-world scale for the viewer.  It is just text for a headline so the text is about 1.75cm tall in the web viewer.  As for the lamp, moving the lamp closer made no difference.  Its distance from the model is dictated by the camera and teh lamp is just above it.


text:
Video Editor, Why there is audio in gap area?
I'm new in blender video editor. I have seen some tutorials about blender's video editor and I have applied it on a test video clip.
But I saw a strange thing: there is some audio in gap area.
There are audio in red rectangle area. Why?


text:
Weird issue with faces
When I try creating a new face at a certain place, it seems to be back to front or something for some reason. When I bevel the edge the vertices are also in the wrong places.
Here's a few images to show what I mean:
Before I add the new face:

When I add the face:

When I add another face adjacent:

When I try to bevel:

i think flip normals will help you out. https://blender.stackexchange.com/questions/29132/how-do-i-flip-normals-on-this-model

@user2038206 You were right. Thank you :)


text:
Particles/fluid attaches or fills the volume of an object
Holla,
Right, so I'm curious on how to achieve a certain effect via two different approaches.
What I'm sort of trying to achieve: https://www.youtube.com/watch?v=KFYFh8w4758
Case 1: I'm looking for a method for particles to exit the emitter, follow a path until near the target object, and afterwards be attracted and stick to the surface of the object, or fill the volume.
Case 2: Same thing, but closer to the Daredevil intro, where the particles fill the exterior of the shape from bottom up.
I couldn't find anything remotely close online, so any help would be hugely appreciated!


text:
When I open blender I have some issues

When I open Blender this is what happens when I start a new project. How do I fix this issue? I also tried to add a Mesh, just as a circle and it did what the second picture shows. I don't even know how this happened.

Check if your hardware fulfills the minimum requirements. If its does, try to update your graphics driver. If it doesn't use an older version of Blender with lower requirements or upgrade your hardware.

Hi. Please make the title of your question specific to the problem you are having and not just the general topic. Thanks.

It seems that your startup file has some issues. You can go back to the factory startup file by doing the following:

Go to File > Defaults > Load Factory Settings. This loads in the startup file that would come with a new installation of Blender.
Go to File > Defaults > Save Startup File. This saves the current .blend file (in this case, the factory one you just loaded) as the startup one.
If 1 and 2 do not solve your problem, you may also have to reset your preferences by going to Edit > Preferences (while in the factory file), click on the menu button in the bottom left corner, and click Save Preferences.
If 1, 2, and 3 still do not solve your problem, you may have to reinstall Blender.


text:
is there a way to freestyle the trasnparent images?

So i made the mout on a plane and used a mix shader and transparent shader to make it transparent, i only want the external freestyle line, and want the mouth highlighted as well but it only out lines the plane

With Freestyle, no, this is not possible; Freestyle acts on the geometry, not the rendered alpha.
However, it is possible to mimic Freestyle in the compositor by using edge detection to spot the transition between regions - in this case from opaque (low alpha) to transparent (high alpha).
See https://blender.stackexchange.com/a/186173/29586 for an example using the Normal and the Depth to detect edges - in your case you could use the same technique on the Alpha as is used on Depth. This will detect the edges of transparency.


text:
How to make this stadium roof in Blender?
How to make this roof in Blender using modifiers? This is Bunyodkor stadium.

You can search more images on google.

Hello :). Please, tell us what you tried and where exactly you are stuck. So it's not just asking for a tutorial.

@cegaton I don't think it would hurt to give a few pointers

Alright...this isn't an answer yet, but I just wanted to include this reference image which helps you get a better sense of the structure for now. This is going to be a long one.

I'm not going to go into all the fine details on how to go about modelling this, but here are some general tips.
1) Model a single exterior pillar, than use an Array modifier then a Curve modifier. This will allow you to repeat the pillar across the exterior of the arena.
2) Use a Cloth simulation for the drapes. You're going to need to subdivide it a lot, and add a lot of wrinkles into the base cloth mesh so that there is enough cloth to produce the wave effect. The cloth will have to be shaped similar to the arena's curvature, so it doesn't look like a tablecloth draped over the arena.
As for the collision objects, notice in the reference image I included how there appears to be strings pointing towards the center of the arena that are holding up the drapes. Thus, you can imitate this by creating an array of invisible cylinders for the cloth to wrap around.

3) As far as the physics settings for the cloth go, you're going to want to reduce the various stiffness settings to allow it to bend more easily.
I've done a rough render of the arena shown below using this method. It obviously could use more work, but I think it gets the point across enough.
Hope this helps!


text:
begin_result(): error with argument 3, "w" - Function.w expected an int type, not float
def update_result(engine, width, height, output_file):
    # debug("Reading result %s %d %d" % (output_file, width, height))
    try:
        result = engine.begin_result( 0, 0, width, height)
        lay = result.layers[0]
        lay.load_from_file( output_file)
        engine.end_result( result, cancel=False, do_merge_results=True)
        return True
    except:
        traceback.print_exc()
        engine.end_result( None, cancel=True, do_merge_results=False)
        pass
    return False

result = engine.begin_result( 0, 0, width, height)

here I've got an error like: "begin_result(): error with argument 3, "w" - Function.w expected an int type, not float"
result = engine.begin_result( 0, 0, width, height)

any helps, guys?
It works fine in Blender 3.1.0 alpha but with 3.2.0 it gaves me error

int(width), int(height)? https://stackoverflow.com/questions/3387655/safest-way-to-convert-float-to-integer-in-python

Thanks. It works fine ))

Convert the floats to integers: https://docs.python.org/3/library/functions.html#int
int(width), int(height)

Safest way to convert float to integer in python?


text:
How to make default path to the executable file via Blender Python API?
I'm working on render engine which need to select binary executable file for working engine properly but I would like to include that binary executable file inside my addon (e.g.: <my_addon\bin\engine.exe>) and post relative path to that exe file via addon istelf not as "Select path to exe file"-like method. By default for selecting path to exe file is works like this on my addon:
exe_bin_dir: bpy.props.StringProperty(name="",
                                             description="",
                                             default=util.switchpath(tempfile.gettempdir())+'/',

There is "util.switchpath" not by default, it does mean it takes "switchpath" defined operator from inside "util.py" file and pin here.
So, my question is how to code for make default path to my addon like for example:
exe_bin_dir: bpy.props.StringProperty(name="",
                                         description="",
                                         default="./<my_addon/bin/engine.exe>"

What am I must overwrite here on three dots?
"default=..."

Why would the render engine be an exe file?

The addon itself is an exporter which export scene and then it will open with that executable file as command line method. Otherwise the addon itself cannot do the job without the exe file.

You didn’t explain why the render engine needs to be a separate executable file.

The engine is not exe file. The engine itself binary exe file which has core inside it pre-compiled. My addon is exporter and render scenes via exporter as geometries and naterials and finally render it inside Blender by using that exe file command-line mode.

What engine are you using that you only have access to as an executable?

pbrtv4 by matt pharr and wenzel jakob

That render engine is open source, and is written in C++, as is Cycles. I recommend you look into the possibility of implementing it the same way Cycles is.

If I understand correctly, you want your adodn to select this file automatically, but also to let the user define an other path if they want to ? Why don't you hardcode the path and use a string property path that's empty by default ? if the user changes this path, then use this one, else use the hardcoded one ?

Yes, I would like addon will automatically search that exe file and use them by default not user changes the direction. Because I will put exe file by default inside to "bin" direction of the addon.

I solved my problem with this method:
curentDirectory = os.path.abspath(os.path.dirname(__file__))

class EngineRenderSettings(bpy.types.PropertyGroup):

exe_bin_dir: bpy.props.StringProperty(name="",
                                         description="",
                                         default=os.path.join(os.path.dirname(curentDirectory), 'bin'),
                                         subtype='DIR_PATH')


text:
How can I copy and transform a bone's location movement to another bone?
I'm trying to setup root motion for an animation that I have but I'm struggling to get it working right.
My armature has a root bone named root and its child is the pelvis bone.
This is the original animation:

What I'm trying to do is copy the location keyframe data from the pelvis bone to the root bone. I thought it would be as straightforward as this for each keyframe:
root_bone.location = pelvis_bone.location

But this results in:

After some digging I noticed that I get the same results with the unmodified animation if I uncheck "Local location" under the pelvis bone's "Relations".

So I'm guessing I need to transform pelvis_bone.location somehow? I don't understand in what way though.

As thoose 2 bones have a different orientation in edit mode, transferring the motion from one to the other is not a simple matter of copying and pasting keyframes.
Some deep math and Python code can be used for this purpose, but the simplest way (that I often use) is to bake the pelvis animation to an empty, and then bake the empty animation to the root.
To do so:

Add to the animation a keyframe in which the whole armature is in rest pose and perform any of the following operations with the timeline set on that frame (I assume that the root bone in rest pose has 000, 000, 111 transform values)

Add an empty in the same exact location of the pelvis bone, set a copy location constraint targeting that bone, then go to Menu > Object > Animation > Bake action (all preferences turned on)

In the graph editor move the X loc curve as a whole to bring the X value at current frame to 0 (manually or using simple math operations). Do the same for Y and Z loc curves.

Add to the root bone a child of bone constraint targeting the empty (do not confuse object constraints with bone constraints)

In pose mode go to Menu > Pose > Animation > Bake action (all preferences turned on)

Delete or turn off loc animation of pelvis bone, delete the empty.


text:
Proxy/Link –> Problem seeing colored Proxy rig over black Linked rig
Hi blender stackexchange community!
I'm trying to Link my rigged character into a blank animation scene for the first time, to be able to rework my source scene in the future and get updates in all my animation scenes.
The collection-linking process works, then I create a proxy of the rig selecting only the Armature (that works too). My problem is that when I'm in Pose mode with the Proxy only selected, The black linked-collection (and rig) overlaps over my colored Proxy-rig (the "Bone Groups" colors I initially chose in my source scene). I actually somehow see some of the colored controllers(bones), but not the others.
That's the original colored Armature:

And that's when I show the linked-collection:

Is there a way to hide all the rigging stuff in the black linked-collection and only keep the geometry shown, so that the colored Proxy-rig controllers are the only ones showing up?
I tried to make the Proxy "In front" of the Linked-collection, but it doesn't work. And If I hide the linked-collection, I'm missing the geometry.
Thank you very much for your feedback!
Carl

I think I have the answer (sorry for English, it's not my main language). All you have to do is disable the rig in the viewport (hide too). Save the file. Then follow the steps you did before (link colecction and make proxy) and you are done.

Amazing Joel! Thank you! I will try that soon! :)

Select your proxy and go to Object Properties -> Viewport Display and put your Proxy in Front and display as Solid. Let me know, if this solved your problem.

THanks Atkay, I'll try that!


text:
Table Cloth/Sheet Ghost
I’m a beginner and don’t know very much about cloth simulations yet. I’m trying to make a little animation of a cloth falling onto a table and then a sphere comes into frame and flies around the table before eventually going under the table and coming up through the table. When it comes up through the table, I want the cloth to now be draped over the sphere, like a sheet ghost. When I do this, the sphere lifts the cloth slightly before just breaking right through it. Is there a way for the cloth to move with the sphere when the sphere comes up through the table??

it depends on your settings and how quick the movement is. Have you applied the scale to the objects (Ctrl+A > Scale in Object mode)?

please share your file so that we can test: https://pasteall.org/blend/


text:
how to render from frame before 0 (minus frame)?
I have an animation that I messed up and had to start it from frame -20, but when I render it starts from frame 0, how do I render from there. Thanks

you need to move all your keyframes, or maybe there's a script to move the whole timeline?

You can allow negative frames by checking in: Edit>>Preferences>>Animation>>Timeline>>"Allow Negative Frames"

@FFeller yes but it doesn't seem to allow you to start a render before frame 0

@moonboots You can't type in a negative start frame, but if you click on a negative frame in the timeline and hit ctrl+home, it works fine. (I always use this method, thats why I didn't realized this).


text:
how to retain colour when you import .stl file into blender
I had a .spk file, then exported it into blender as a .stl file. but when I imported it into blender and went into rendered mode there was no colour. there was no colour in material preview mode as well.

Seems stl file format doesn't support colors by default, only in its binary version: https://en.wikipedia.org/wiki/STL_(file_format)

is there like an add-on for this maybe?


text:
How to select all marked 'seamed edges'
I have a maze and I want to select all of the 'seamed edges'.Maybe there is an addon for this? Thanks in advance.

You can do this with "Select Similar".
Select one of your edges with a seam, then go Select > Select Similar > Seam, to quickly select all the edges with seams.


text:
Bake selected constraints relatively to the parent?
I need to store an animation of the object while preserving its dependencies to the parent. The object is connected to the bone using the Child Of constraint. I transferred some animation to it using the Copy Transforms constraint. How do I bake the Copy Transforms but keep the Child Of? So if I turn off the "Child of" I will have an animation playing in 0;0 coordinates.


text:
Subdivision modifier isn't working
That's something new. Blender 3.3.0 ignores the subdivision modifier in my scene. Has anybody ever had the problem?
I checked different viewport shading options.
Checked GPU Subdivisions in the preferences.
Render sees the subdivision just fine. Viewport doesn't.
I'm kinda out of options

Figured out. In the Render Properties uncheck Simplify


text:
Change the shape of the "solidify" edge
community! I need to solidify the flat mesh but the edge should have some C-shape on it. I know it is supposed to be done with GN, and I saw the solution some time ago, but I can't find it anywhere now when I actually need it. So here's the approximate sketch of what I need (yellow overdraw) and the nodes that I have by far, that are providing me the flat edge. I need to add some loops on the thickness edge and bend them (preferably controlling with the curve).
Any advise?


text:
Window's glass - black stripes
Does anybody has an idea, why the black artefact is rendered as on attached screenshot?
Glass material is just assigned to two faces of the window.

what happens if you just use the Glass BSDF node, just for testing.

Might be something to do with your second mix shader node having nothing in the second input?


text:
constraining object to a Joint
There are a problem about constrain a group object to a joint.like is

I want let the group of glasses to be constraint by the head joint.
Could you tell me how to achieve it?
Thank you!!
Hanwen

What do you mean exactly? If you mean you want the glasses to be parented to the head bone, you can parent the glasses to the armature with the "With Empty Groups" option, then select the glasses, go in Edit mode, select all, and in the Properties panel > Data > Vertex Groups, select the group to which the glasses are supposed to be part of (it has the name of the bone, like for example Head), and click the Assign button

You can also parent directly to the bone if you want.

yes it's just that if he ever decides to join the glasses with the character object, the glasses will already be assigned to the right bone


text:
Rigging Problem
I am a newbie to the Blender.
I always have some confusion about the rigging.
Hoping you can provide some insight into a bit of confusion i have.
If you are Maya user before, u might know there are three different way to let
 a Joint follow another one.
1, you can parent them.
2,you can constrain them.
3, you can use the relationship Editor to connect their parameters.
The reason you use three different way to constrain the two joints is that have a clear outline and let the main control curve can scale the Object.
So, I want know is there any similar way to control joints?
Take the project as example.

If I want the L_Arm IK01 follow the Spine02 and I do not want parent them, is there any other way to achieve it?
Could you give me some advises about the blender rigging?

your question is too broad, you should ask questions one by one. About your precise question: you want L_Arm IK01 to follow Spine02 but you don't want to parent them, but why don't you want to parent them, as it would allow you to make arm follow spine? You could give the arm a child constraint but I'm not sure it's the solution. If you want your arm to be independent, IK is precisely here for this purpose, so maybe give a bit more details...

In general, in blender you can use parenting, constraints or drivers to copy some or all of one object's transformations to another.


text:
Vector node question
I am a Newbie in blender.
In general, If i do a character in Maya, I will sculpture a high poly in Zbrush and export the normal map and displacement map to Maya. Then I texture it and rig it.
But, I found there are some different in blender.
So, Hoping you can tell me what is the different between vector map, normal map and bump map in blender? and the different between displacement map in maya? and the pipeline of character modeling in blender.

Bump Mapping and Normal Mapping
Bump mapping and normal mapping are technically the same thing. They both add fake vectors and manipulate existing ones to generate the effect of higher polygon numbers by faking geometry light reflections. Both can be used for render purposes and in game engines as well. The difference between them is the amount of information they yield.
Bump maps are grey scale images, they provide their information using values between black and white. Normal maps are RGB images, they provide additional directional information using red, green and blue.
The modern way to fake geometry through light reflections are normal maps due to higher accuracy. Some games still use bump maps in some cases, where the effect is less noticeable and the smaller file size reduces loading times.
Micro Displacement (not to be confused with Vector Mapping)
Micro displacement at this point of Blender development is only possible within Cycles render engine for render purposes. At this point it cannot be baked to a texture. It works only on high-poly models and only offers benefits in conjunction with Blenders fairly new adaptive subdivision feature.
Micro displacement provides more detail on models in general and adaptive subdivision reduces detail on objects that are further away from the camera. Combine them and you reduce render times significantly.
Vector Mapping Node (as shown in your screenshot)
The vector mapping node is used to transform image or procedural textures. You can manipulate their size, rotation and location.

The maps are the same as in any other software.
Displacement Map
Widely used. Grayscale data, often 16 or 32bit to avoid stair casing. Offsets the vertex points in the normal direction. Use tessellation for higher details.
Vector Displacement Map
Used in Z-brush and some other software. Image data contains a vector offset  (16 or 32 bit) that is used to displace a vertex. Since this is a vector the displacement is not limited to the normal axis. Use tessellation for higher details.
Can be baked from a shape key with a scripts.
Normal Map
Used widely. Image data contains the surface angle vector which is used for light reflection and shadow calculations. Can be in object space or tangent space. Can be in OpenGL format or DirectX format (direction of Y swaps). Does not offset geometry.
Bake with built in, or external tools. Often from high-poly to low poly.
Bump map
Old technique that is in most cases replaced with Normal Maps. Image data contains gray scale where the gradient between dark and light values are used to create normals. Does not offset the geometry but can be used for parallax offset in some softwares. Often authored freely with photoshop or gimp.


text:
Array modifier not duplicating around an empty
I am very new to Blender but I have spent at least eight hours trying to solve my problem using You tube tutorials with no luck I am trying to use the array modifier to put treads around a torus. In edit mode I move it to where I want it. I select the tread object and add an array modifier. I set the count and it works like it should.Now I add an empty and select object mode and then I select the empty. If I rotate the empty now the tread object rotates but  now it's one object even though the count is set to 25.

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

Not clear what the problem is. When arrayed with modifier there won't be any individual objects and you can't edit them separately unless you apply modifier. If you want to spread objects with circular array make sure to put origin of the object to be arrayed in the same place as for the empty they are arrayed around


text:
Rotating a bezier path
I'm trying to make a graphic that describes how to orient a planetary orbit in 3D.  I animate my planet going around in an ellipse on a Bezier curve.

Next, I want to perform several rotations on the ellipse in space.
What is a simple 30deg x-rotation for the ellipse cylinder object is a -90 x, -30 y and 90 z rotation for the Bezier curve, which it accomplishes at a different rate. In this image you can seem them both rotating, but the Bezier ellipse lagging behind the cylinder.
Any idea what might be going on and how to fix it so they all rotate together at the same speed?
I'm using Blender 2.79 on Windows 10.

This really shouldn't happen.. did you apply the transforms of the curve and ellipse at the 0 position, so their local axes are coincident? (..and BTW, it's possible you don't need the cylinder at all, you could just use a filled and extruded  2D curve.. the planet could still follow that....)

everything had their origins at the center of the "Sun" at (0,0,0)

..and the local axes were aligned to the world?

No idea why they behave this differently. But you could try parenting you curve to your object by selecting the curve first then the object (with Shift held down) and hitting Ctrl+P on the keyboard. Then you can animate your cylinder object and the curve will follow automatically.


text:
Thread limited processing in 2.8 builds?
I have been trying the 2.8 Blender Bot builds. None of them have even attempted to use more than the first 16 processing threads of my Threadripper CPU, leaving 75% of the computing power idle. Many 2.8 features "burn up" these first 16 threads. Is it possible to use these builds across my entire 64 thread CPU?

By "processing" you mean CPU rendering? Please specify.

No, not rendering. In this case, sculpt editing a mesh. The 2.8 Windows build blasts away at the first 16 threads, with each stroke, but ignores the rest of the 64 potential threads. If I were to render with the CPU, however, it would still only utilize the first 16 threads. I suspect these builds are inadvertently limited to 8 cores of processing. If it were a trivial change in the builder, it would be great to have the entire 64 threads enabled!

The rendering is weird, maybe there is some optimization to be done. As a bit offtopic: also try zbrush, it will use all threads nicely. If performance is a concern and you payed that much for your HW you might as well use it, it's way faster with better brushes.

Some tasks have limits to how far you can reasonably parallelise them, however I would have though that with rendering particularly you should be able to benefit. This is likely a bug and should be reported to https://developer.blender.org/


text:
EEVEE Glass shader doesn't show through itself
I am having an issue with my glass shader where objects using it do not show up through each other.

Here is my current setup for the shader:

No.  Refraction, which the glass shader uses, is very limited in Eevee.  This is the nature of rasterization vs. raytracing.  Use Cycles if you want to do crazy things with refraction.

Try something like this for your "glass" shader. As Nathan mentioned, rasterized transparency will always be lacking compared to Raytracing, and though EEVEE really doesn't like transparency through transparency, this shader attempts to strike a happy medium. Try it and see for yourself. Pay attention to the Blend Modes on the right, including the backface culling and show backface checkboxes (I just noticed Show backface is covered in my image, but it is un-checked):

However, glass is very much assisted (both in eevee and Cycles) by the use of an HDRI environment map. Switch to your World shading tab and add an Environment Texture (not Image Texture) with your HDRI. Blender's built in HDRI's are in the blender folder at .../2.93/datafiles/studiolights/world and many more can be found online for free. One of the most popular places is HDRI Haven (https://hdrihaven.com/hdris/).

If you want the effect from the lighting, but don't want the image in your background, you can separate them by using a Mix Shader, using the Is Camera Ray output of a Light Path node as the mix factor:

Not a bad solution. Before this, I used a cheap workaround of just mixing between a the Glass BSDF and a Transparent BSDF. That way you get just enough proper transparency and refraction for it to be 'good enough'.

Make sure that Render Properties -> Screen Space Reflections -> Refraction is on

In EEVEE Objects with refraction on in their shader can't be seen when they're behind other objects.
Here's the best "fake glass" EEVEE Shader I've found

In this shader disable Screen Space Refraction.
Set the blend mode to "Alpha Blend"
enable backface culling
The RGB Curves gives fine control over the Fresnel effect but isn't really necessary


text:
Edit string input for geometry nodes?
How can I edit a string input in geometry nodes from the modifier properties? It seems to be the only type that cannot be edited (other than "Geometry" which just doesn't display at all).

I have had no trouble with this. Are you sure the type of input is set right?

Yes, it's set to "String". I have another input for a camera set to "Object" and it works just fine.

What version of Blender are you using?

3.5.1. I noticed the issue on 3.5.0, but updating changed nothing in a fresh project.

No problem editing string from modifier:

Make sure you have "Hide in Modifier" unchecked:

Edit:
Blender 3.5.1

Nothing out of the ordinary as far as I can tell:
https://imgur.com/a/Bg29y9O
Also, "Hide in Modifier" doesn't seem to work either:

@Sandberg Strange... it does look correct in your screenshot. Could you maybe upload the file in your question? Or probably is something messed up with the node, does it work if you delete it and create a new one?

It seems like you're using a custom display of the modifier stack, either through modifying the source code or an add-on. Try disabling it or using an official version

@Gorgious Heaven's sake, that was it. And it looks like the issue was fixed in the latest version of the add-on.


text:
Custom startup scene breaks addons?
I run Blender with my own custom startup scene. I've installed some new addons recently and a couple of them just didn't work with no error or indication of the problem. What I discovered is that opening Blender in the default startup scene with my same preferences fixes the problem.
What exactly would cause a modified startup scene to break addon functionality and how could this be properly prevented? There shouldn't be anything fundamentally different between it and the default.

I guess this is very highly speculative to answer since we have no information how much and what you have changed in your custom startup scene, and even if you would have revealed which new addons are affected by this, you cannot expect us to know how all these addons work.

@GordonBrinkmann I figured, but the only things that were changed were the layout and removing the default objects. Resetting preferences changed nothing, but resetting the startup scene did. Only thing I've read that could indicate is how much might change between versions, potentially requiring re-building your startup scene.

I'm not sure what versions have to do with it. Are those addons made for a different version of Blender? Or have you used an old startup file for a newer version of Blender or...?

@GordonBrinkmann The addons are verified for the latest version, so I assume it's because I was using an old startup file made on a previous version. Not sure why that's would cause problems though.

Well, the startup file stores a lot of things, not only the default cube, lamp and camera, but also the render engine settings, some editor settings etc. And some of the things are changed or maybe even vanished from one version to another so I can imagine that this causes problems. And in your question  you just said your own custom startup scene. Customizing alone usually is no problem - that's why you have the option to save it. But features change, so it's best to customize the file that matches the version it is used in.

@GordonBrinkmann The weird thing is that disabling and enabling the addon in the modified file does nothing, so the conflict must be more deeply embedded. Oh well.

It's not weird to me now that I know that you used an old startup file. I don't think it has to do with the addons per se, since the enabling/disabling of them is stored in the user preferences which you can change without having to save them in the startup file. I guess it's something in the basic features of Blender that is incompatible with the old file, so the foundation is the problem, not the addons built on top of that.


text:
When rendering in Eevee, result is zoomed in compared to viewport camera
I've been playing about with Blender 2.8, getting use to the interface etc. I've rendered a still frame from an animation, but the resulting image outputted is slightly zoomed in, this is the same wether I render in Eevee or Cycles. am I doing something wrong? or is this some weird bug?

screen cap of eevee camera view

Actual Eevee render

Cycles render

camera settings
If you need to see anything else please let me know
Best
simon


text:
How do I make it say (1) Plane in object and edit mode?
I have a plane in both object and edit mode but near the axes it says 0 plane. Is there any way I can fix this?
(Sorry if my explanation doesn’t make sense)

Press the right arrow on your keyboard. That will change the current frame to the next one that is frame 1. The number indicates current frame.

Thank you  , sorry for being an idiot♀


text:
LuxCoreRender render times incredibly slow
I started a render with LuxCoreRender while ago and I'm experiencing a problem
Simply it takes 12 minutes or more just to initialize ever single frame, and if I try to stop it before the frame is initialized, blender crashes.
May it be all the volumetrics, lights or...? Seems like something is heavy but I didn't do anything different from what I did with Cycles. Any idea of what the hell is happening?

Just figured out. LuxCoreRender doesn't like hair that much as Cycles does, so try to not increase the value too much. I also disabled my CPU and let the GPU work only and render went a bit faster tho.


text:
Blender has problems rendering some parts of an imported FBX model
I am a data scientist, with no knowledge on 3D modeling, and my goal is to make various rendering of a model by controlling the camera through a Python script. Writing the Python script was quite easy (great interface!) but I'm facing rendering problems and can't figure out how to tackle this.
The model has been made in some Autodesk software, with very simple forms (mostly cylinders/tubes). I have imported the corresponding FBX file. Blender has problems rendering some parts of it. The model probably need some cleaning… but it's actually rendered correctly in MS 3D Viewer (and I suppose, in the original Autodesk software), so there's likely a way to reach that in Blender without cleaning too much?
Here's a snapshot using the viewport's solid view:

Here's a snapshot using the viewport's render preview:

Here's a snapshot from MS 3D viewer:

I have tried:

removing the hidden/unnecessary faces
using some boolean union / split edge modifiers (but I might have chosen faces that were not meaningful)
switching from shade smooth to shade flat
changing the renderer for eevee or cycles, and playing with the parameters

The "cycles" renderer does not show these mistakes, but is quite CPU/GPU intensive and since I want to take +100000 captures, I'd rather avoid it.
Do you have any advice on what I can try?
Maybe there's another renderer in the add-ons that I can try?
Thank you!

I'm not sure where's your problem, but sometimes you need to reset the split normals of imported fbx, you could try Properties panel > Object Data > Geometry Data > Clear Custom Split Normals Data. If it doesn't work, maybe share your file: https://pasteall.org/blend/

Is the model by any chance very far from the world origin ?

Did you export the textures/

Thanks for taking time to help me!
@Gorgious was correct: my model was very far from the world origin! I've added a body.matrix_world.translation operation in my script to automatically fix this, and the rendering is now impeccable!

@FrançoisP. It's a very common floating point precision error :) Blender (and many other 3D softs) don't bode well with very high coordinates. You can also set the object origin to geometry, then clear the transforms

@Gorgious
I do not see how I can "set the object origin to geometry, then clear the transforms".
Do I set obj.location (they are all equal to (0,0,0)) to the mean of the vertex coordinates?
Then what is the property corresponding to the "transforms" so I can clear them? I've looked at matrix_world, matrix_basis, matrix_local and none of them seem affected when I change location.


text:
Cannot use/find a setting in physic settings
I'm new to blender and I'm enjoying it. You guys made it absolutely amazing.
My problem is  about some settings, I'm creating Animated rain by watching a tutorial in YouTube,
but it's on Blender 2.8 and I'm using  Blender 2.92. In physic settings fluid
option the settings are different in 2 versions, I need to change speed, subdivision,
particle generation, and baking it after that. I need those settings, with out it  I can't finish that part. So I need help. And I have
another problem in rain drop size, when rain drops the
size of the reflection is big and they all combined together and it doesn't seem like dropping
actually real .
I don't know what to do next.
So, What can I do for it?
I expecting answers soon as possible and other options.
If I can't do anything for the  physic setting problem,
can I open the 2.92 Blender file in 2.8 Blender?
I'm 15 and doing this project and I need to complete it or I'll get the name "Quitter"
Thank You,
Yours Sincerely,
-Arosh Adithyan

I don't think they have changed.
you should select the domain object to see those options.

and also you can open projects in other version.

2.80 fkuid simulation was change a bit for 2.92. You could download 2.80 from the website


text:
How do I make my object look smooth without using the subdivision surface modifier?
Sorry if I phrase this incorrectly but I was following a tutorial for a character model (the link should be below, end of part 4 and beginning of part 5) and I don't understand how he got the body to look so smooth. I tried applying the subdivision surface modifier but it only made my object look flatter, like this:
It originally looks like this in sculpt mode:
And like this in Object Mode:
I want it to look smooth and not so blocky like in the tutorial:
https://www.youtube.com/watch?v=wdsY4BtlcpQ&list=PLvgIVNDU-Dxjb3eukDF5W0l0-6ShO9OiM&index=5
Thank you for your help
P.S.: Sorry if I added too many pictures to get my point across. Also, I am a novice at Blender, and yes, I know, even without the blockiness of my character's body, it doesn't look like the one in the tutorial. I'm doing my best so please disregard that if you can.

I think most of the effect you're seeing comes from switching the default Shade Flat (which uses a single Normal per face when shading, from what I can tell) to Shade Smooth (which interpolates -- that is, smoothly averages -- between the face normals to get useful normal information in between the basic face normals).
For example, here's an Icosphere with Shade Flat on by default:

And here's what happens with Shade Smooth turned on (in the sub-menu indicated in the above image):

Secondarily, you may also find it useful to use the Smooth Vertex (from the Vertex sub-menu in Edit Mode) transformation to improve the smoothness of the model. I believe Daniel Kreuter, the YouTuber who made the tutorial you're following (I recognize the mesh-work, having followed the same tutorial myself in the past), makes liberal use of Smooth Vertex; he explains this in one of the tutorial's earliest videos (and that he likes to hotkey it to the 'Q' key).


text:
How do I get rid of the tear in the middle of my object after using the mirror modifier?
I'm sorry if this question has already been asked, but I was following a tutorial and after sculpting, I reapplied the mirror modifier but my mesh looks like this:
Is there is any way to fix this without applying or deleting the mirror modifier.
Thank you, a blender novice

it looks like you can't use both Multires and Mirror, so maybe delete the Mirror and if you want to mirror, go in Edit mode and go in the bottom menu > Mesh > Symmetrize, it will symmetrize your object with the Multires sculpting

Put the mirror modifier before the multires. Keep clipping on, but make sure all the vertices at the middle are snapped over to center line.

I tried but it said "Cannot move above modifier requiring original data"

Can you try to delete multires modifier and add it back after mirror


text:
How do I make my mesh look thicker around the collar?
Is there a way to increase the thickness just around one part, the collar,  the jacket? It is a seperate abject from the dress. Thank you.

Try the solidify modifier on the jacket


text:
How to " no-flood-fill " a texture?
By No-Flood-Fill I mean filling like in paint. A fill brush in blender fills the entire object. This is not the result I am looking for. However, I want to fill only instead of a certain color?
Any help would be really appreciated, thanks. :D

Use the Fill Tool in the 2d Image Editor and you can then use the Thresh hold setting to dial in your desired tolerance. This threshold feature is not possible as of yet in the 3D view in Texture Paint mode, as it is a different process for painting under the hood. I believe that google search should have brought you to a thread here if I am not mistaken(I made that picture).

Hum... There's supposed to be a Threshold option allowing you to manage that, but... I can't find it myself anymore...
I just found a picture on google :

Dunno why it's gone. Probably shouldn't be, maybe a bug.

I don't know why this is downvoted, I'm seeing the same thing. I can't find the threshold setting under fill. And I'm doing it on the 2D side. Is this a bug?!

https://blender.stackexchange.com/questions/174101/trying-to-find-the-threshold-setting-for-the-fill-brush-in-2-8?rq=1
I found this link, maybe this is what you are looking for?

yes, it's back since then


text:
Rig deformation issue, possibly stuck on something?
I'm having this issue with my model. Once I applied the rig the left side (models right) seems to be snagging on something yet it's a mirror of the right side. Does anyone know what could be causing this? I noticed by moving the other leg it changes the shape of the deformation as well.

do you use bone envelopes? if yes, then they might be overlapping, they seem sticking to the other ankle. you can set the envelope radius in the bones "deform" tab. if you are using vertexgroups additionally, see if thats causing the issue, by unchecking it. the left foot vertices might belong to a group called like the right ankles bone.


text:
Jerky boat motion, how can I smooth this out?
I followed these two methods to animate a large yacht hull:
https://www.youtube.com/watch?v=smArCTzxGpE
&
https://www.youtube.com/watch?v=sfi7HW8qHAo
I'd like to mention that I am a Blender newbie and that I have not finetuned materials, environment and the amount of foam generated in my file.
Basically my ship is guided along a curve with the help of an underwater slider plane.
Here is what I got so far:
https://youtu.be/W1eDkpwtL8U
Unfortunately this is way to fast in boat movements (not boat speed) for a large yacht.
A large yacht would usually not have the transom exit the water that far.
What can I do about this?
I tried already to reduce the rotation around the horizontal axis in the hope that would smooth the motion out.
Please have a look for this on the attached screenshot of my setup.
Or is it more of a scaling issue between ocean and yacht?
This is closer to where I want to go:
https://www.youtube.com/watch?v=UtoG8jPQEyE
But I'd like to use a slightly(!) less slick ocean.
A last question, this:
https://youtu.be/zlIVtofxY-I
has a nice wave distribution along the hull (=bow wave, followed by through and stern wave) What is the method to achieve this? I did not understand that from the description given.
Is it the shape of the plane which slides along the pathcurve? Do I need a modifier on it?
Thanks up front for your input!

Drop us your .blend file using https://blend-exchange.giantcowfilms.com

Uups Lukasz, just saw your reply. I had missed it before.
Thank you for offering that, but I am not able to share the actual file due to copyright issues.
Still, I got it to work a fair bit.
Now there are more questions arising. Maybe someone can help on the base of the current result:

https://youtu.be/2kjzzCOgbDU

Current questions are:
1)WAKE
How can I have the wake fade out gently, rather than sudden as seen in youtube?
Looks also like its stretching and suddenly does snap more towards the boat like a rubberband. I suspect this is due to the tiled ocean surface.
2)WAVE ALONG HULL
I like to deform the bowwave and also show the through forming along the hull when the boat is moving.
Whats the best way to do that?

3)SEASURFACE
I am working in mm units throughout and do not want to change this. Still I want to achieve a less slick sea surface with more and smaller waves. Any idea how this could be done?
I tried already more chopyness, but that does not help.
4)PICTURES
How can I attach some screenshot in this thread?
Thanks for any help.


text:
Blender 2.8 Cycles - Winter landscape, weird artefacts in few of the cut-out trees
I come across an issue when rendering tree particles.
All of my trees in the attached image are from the source tree. The source tree is free of alpha mask problems. As one can see, most of them show up perfectly fine.
Still, some show strange black artefacts. Which seems weird as they are part of the same particle system.
Any suggestions? I appreciate your help.
Thanks.

You will need to increase the transparency bounces in the render settings.

https://blender.stackexchange.com/questions/42023/transparent-textured-planes-produce-black-artifacts

Thanks Leander & Duarte. Btw, I had to bump it up considerably. 12 transparency bounces did not fix it...

24 did fix it...


text:
How can I change video (or image sequence) speed (slow or fast) in blender composition?
I want to use slow down effect in composition. I can't find any control. I found time node.
https://docs.blender.org/manual/en/dev/compositing/types/input/time.html?highlight=time%20node#example
But I can't figure out how to use it.

I'm not particularly familiar with this area of blender, but for changing timings I think you want the video sequence editor not the compositor.

You want to use Time remapping, a quick google search for that will help you.  Also when I get to a computer I will update this answer.

Time remapping will not work in my case. I want to change play back speed of one image sequence but I don't want to alter another sequence in composition. Time remapping will change speed of both image sequences. Thanks.

if you are using the video sequencer you can add an effect called speed control to your clip.


text:
Creating a path with differential equations
I'm currently trying to create a 3-D vector field based on an equation. Once I create a vector field, how to actually make the object move along the vector field when placed at a point?
My Approach:
Every vector field has an associated system of differential equations. For example, for a vector field, $$\vec A = x \hat{i}+y \hat{j}+z \hat{k}$$ the associated system differential equations are, $$\frac{dx}{dt}=x \\ \frac{dy}{dt} = y\\ \frac{dz}{dt}=z$$ and the corresponding solutions are $$x(t)=x_0 e^t\\ y(t)=y_0e^t \\ z(t)=z_0e^t$$
So now, we have path(i.e.) by varying t, we obtain a set of $(x,y,z)$.
Is there a way to solve this system of ODEs with blender. I found an answer, that was relevant, Can you animate objects using differential equations?, but I couldn't understand how to implement all those in this context.

When I have understood you correctly, you have already the solution of your diff eq, and you know x0, y0, z0 as parameters of this solution, defining the start location. When you run under Python a loop by incrementing t in discrete steps, you will be able to create a 3d chain of vertices with these coordinates and use this polygon as path for animation (convert to a curve, if needed). Since I am a newbie myself, I cannot provide any code, however.
Greetings from Germany, Tschöbbel

Thank you for answering. I just gave an example, for a field. In general, $\vec A= P \hat{i} + Q \hat{j} + R \hat{k} $ the corresponding equations are, $\dfrac{dx}{dt}=P, , \dfrac{dy}{dt} = Q,, \dfrac{dz}{dt}=R$ for which I don't know the solutions.


text:
Blender Fracture Build Bake to Animation for Alembic export
I am using the custom Fracture Blender build for a tree shatter simulation: https://wiki.blender.org/index.php/User:Scorpion81/Fracture_Documentation
Haven't used the physics system in Blender at all, but wanted to see if it was possible to have a physics simulation of a tree shattering and export that as an .abc for import into Unreal Engine.  I can run the simulation just fine, but can't figure out how to correctly bake it so that the results are preserved and can be edited in animation/or exported to Alembic.
Does anyone know of a tutorial on how to do this?
Check out the blend file here:

You should just try to export the set up FM simulation via "File->Export->Alembic". Then set your desired frame range and while exporting, the FM simulation is being run in the background and the mesh is dumped out once per frame. That's why the resulting .abc file becomes rather big, 145 MB in this case. And note you will have to re-map the materials manually... only the material assignments are exported / imported, but the values of the material settings AFAIK not (they differ between different programs, this might be the reason.)
I have set up an example blend with a tree fracture scene, derived from your initial blend. In blender you should just need to export this to Alembic. But in case you also want to edit something, it becomes much more tricky IMHO.
You could also convert to keyframed objects, but this will mess up the "fixed" normals again (only FM supports this).
Edit: I did not use fixed normals here, because they work better with more regularly divided base geometry, and best with autohide / automerge. But when the simulation runs and the mesh gets hit, you might get temporary artifacts at the splinters. Instead i tried to mimic the behavior with an Edgesplit modifier. The result is not as smooth as the other approach, but is visually "stable".
Here is the example blend:

Hey man, thanks so much, learned a lot from your blend.  My simulation knowledge of blender is very limited, so didn't even realize I had to actually animate the "striking object" I was manually manipulating that.  The fracture build of blender is amazing, love it, the finished result looks amazing in Unreal. It complained about some of the meshes (for some reason it couldn't triangulate them) but once I added a triangulate modifier in blender it imported just fine.

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


text:
Missing faces when switching from Sculpt to Edit mode in Blender
When I switch from Sculpt mode to Edit mode, I run into an issue where the faces on one arm of my model are not showing. Beforehand, I had applied the mirror modifier so that I may use the hide option in sculpt mode. Thank you in advance for any help!
PS. This is the first time I am posting a question so forgive any incorrectness in my methods or if my question is foolish.

Are you sure the faces aren't hidden? In edit mode, hit Alt-H to see if they were hidden.

Oh wow, thanks. I assumed that hiding faces would hide the vertices as well. I had not known it was possible to hide only faces and keep the vertices. Thank you!

You might want to check that you don't have duplicate vertices too. Because according to the screenshot it appears there might be duplicate vertices. Go to the Tools panel, and press the "Remove Doubles" button.

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


text:
How can I render a toon character's head to always be visible in front of his body?
Currently, I am working on a cartoon that will be modeled in 3D and rendered into 2D. The art style we want to go with isn't technically accurate within 3D space. The character has no neck and his head always appears in front of his body whether in front view or side view.
Does anyone know of a way that I can make the head object always visible in front of the character's body object and only through one layer of the character's body? Sort of like how Freestyle has QI range for rendering lines behind a certain number of faces. I want to do that, but for meshes.
Blend File
Reference images:

you could make it a flat object with a constrain to always  point it to the camera

authors: Сергей Верховых


text:
Polygon Artifacts Traversing Solid GIF
I've got a workflow that takes a Gif, converts it to a point cloud, smooths and meshes it using MeshLab and exports a bunch of Obj files. Every Obj contains the color geometry for some part of the image, the modelling is imprecise and there is overlap between some of the boundaries.
Using blender I walk through this solid with a camera using a ortho perspective. Because there is no lighting or advanced rendering I'm using Blender Render and shadeless materials. I think the artifacts are from rendering inside of objects. Towards the end of the solid (frame 170-180), the render start to look cleaner with minimal artifacts.

But for the rest of the traversal I have nasty artifacts like this. Here's the original Gif for reference.
Blender File
Anyone give me some insights on this?


text:
Is it possible to use vertex paint with symmetry? Mirror modifier not an option
Model is rigged, UV-mapped, shape keys made, etc., so I can't cut the model in half and use the mirror modifier to "cheat". Help appreciated.

Spoiler alert, this is only a workaround, there's no native way to paint with symmetry on vertex paint mode, :'(
1) Make a vertex group assigned to one half of the symmetrical model
2) Duplicate-link(pressing "alt-D") the object and mirror the duplicate with "Ctrl + m" and then press "x"
3) Add a "Data Transfer" modifier to the original object
4) Set the source object as the duplicated object
5) Tick "Face Corner Data" and select Vcol, tick on Generate Data Layer at the bottom of the modifier
6) Set the vertex group to the previous vertex group created in 1)
7) You must see the original model with the vertex colors symmetrical and live painting with symmetry, you could apply the modifier when you have finished painting.
8) If the results are not as expected you can play with the method of mapping the source, the default method is "Nearest Corner And Best Matching Normal"
Modifier not viewport seen

Modifier viewport seen, live painting symmetrical vertex colors

PD = I have heard that is pretty hard to implement a x-mirror option for vertex paint mode because vertex color is face-corner data, but I don't believe that, :(

Workaround #2:
If mesh is uv mapped, then load an image texture in a slot and paint with the preferred axis symmetry turned on in the symmetry tab of the painting tool bar.
Save the image to disk, and then go to the Data tab in the Properties editor and add a new vertex color slot. Go to the Bake panel in the Render properties, and turn on 'Textures' for what to bake, and tick the option to 'Bake to Vertex Color'. Press 'Bake' and you should then have your image texture colors delivered to your vertex color slot.

authors: عمر عادل محمد


text:
Rotating watch hands, not working....
Trying to rotate watch hands using an Empty, but no matter what I try, the hand rotates on a weird axis alignment.
What am I doing wrong?
I've tried Parent, Parent Keep Transform, Inverse Parent.
I've tried applying Rotation to the object before parenting and still same issue.
Apply rotation to the empty before parent, just does this weird axis flipping thing.
Thanks,
alldaron

blend file on dropbox:
https://www.dropbox.com/s/g211oqyzvtnvljv/HANDS.blend?dl=0

.... animate the rotation of the watch hands...

You can use a bone instead of the empty to control the hand, just rotate it in object mode to match the hand axis rotation , when you parent the hand to the bone, choose bone in the set parent to menu, then when animating the bone, make sure to do it in pose mode

I appreciate the reply; yes, this is how i rotate it for initial posing, but when I try to animate the rotation over 24 frames by placing keyframes at frame 1 and 24 for rotate, then press play, the animation doesn't adhere to the z-rotation.

example video here: https://youtu.be/5XFYyhyLpVk

Just reset the rotation of all objects, add a 'master' empty, parent the dial and the controlling empty (the one that controlls the hands) to it, animate it at its default position, then you can rotate the 'master' empty to change the whole clock rotation

awesome thanks, one last question, is there any way to do this without resetting the rotations, since the scene is already posed.

I edited my answer, also here's a file with both methods used
http://www.mediafire.com/file/aun1wvukaa5tejj/HANDS.zip


text:
How do I select things behind/near the gizmo?
I've looked everywhere but I can't find a way to select things "behind" the gizmo in 2.80. It's like there's a forcefield that gets in the way. I didn't have this problem in 2.7x. Is there some setting that allows me to select through the gizmo so I don't have to keep disabling it while editing?

I had the same problem and the solution is to go to
Edit > Preferences > Keymap then select Drag under Activate Gizmo.
and it should work.

Thank you... finally don't have to toggle the gizmo on/off to select things. You've saved me from thousands of extra clicks.