Actually you think that the other parts of the mesh won't have the texture displayed because they are off the image in the UV/Image Editor but you need to know that the image is actually repeated as a pattern, that allows you for example to create seamless repeated pattern textures. So you need either to move your other faces on a transparent part of the image, or even don't unwrap these other faces of your object, or as suggested by bstnhnsl, choose Clip mode instead of Repeat in the Image Texture node.

Here is an example of an object that has the same image repeated on another face, while it looks like this other face is off the image:

If I increase the size of my mesh in the UV/Image Editor, you can clearly see what I mean:


Lighting doesn't make objects cast shadows

You need to disable Ambient Occlusion in the world properties.

If you use the shader of the sun itself to light the scene, your texture will be overwhelmed by the emission part and any detail will be lost.

You can emulate the light from the sun by using a point light centered on the sun itself. Remember to set its size to a high enough number so that it is bigger than the sun object or else light won't get through to your planets.
You can then set the emission strength of the sun to a low enough value that it still appears to be glowing but you still see all the details of your texture.

Details on the point light (Adjust these settings depending on your scene) :


Layer Brush

You can find it in the Brush browser:

From the Blender reference manual's page:

  This brush is similar to Draw, except that the height of the displacement layer is capped. This creates the appearance of a solid layer being drawn. This brush does not draw on top of itself; a brush stroke intersects itself. Releasing the mouse button and starting a new stroke will reset the depth and paint on top of the previous stroke.

Persistent base option enabled will allow to sculpt without overlaps.

See the different behavior in the image sequence below:

Remember to set the Intensity of the brush to 1, or the stroke will not reach the "capping" level, leading to an accumulation when you draw upon an already sculpted area.


How can i get a smooth rendered surface (without weird vertex lines)

Subsurf + Bevel is the way! , Kudos to Bithur for helping


Select all targets of an object's Boolean modifiers

Here's a script that adds an operator to do that in the "Select" menu.
I added 3 checkboxes to specifiy if you want to include hidden (eye icon), disabled (monitor icon) or unselectable objects, since by default they can't be selected if they are in either of these states.
The operator selects everything by default, hidden, selectable or not.
import bpy

class SelectBooleansOperator(bpy.types.Operator):
    bl_label = "Select Linked Booleans"
    bl_idname = "object.select_linked_booleans"
    bl_options = {'REGISTER', 'UNDO'}

    extend: bpy.props.BoolProperty(
        name="Extend",
        default=False,
        )

    select_hidden: bpy.props.BoolProperty(
        name="Select Hidden",
        default=True,
        )

    select_disabled: bpy.props.BoolProperty(
        name="Select Disabled",
        default=True,
        )

    select_unselectable: bpy.props.BoolProperty(
        name="Select Unselectable",
        default=True,
        )

    @classmethod
    def poll(cls, context):
        return context.active_object and context.active_object.type == 'MESH'

    def execute(self, context):
        layout = self.layout

        mods = context.active_object.modifiers

        for mod in mods:
            if mod.type != 'BOOLEAN':
                continue

            obj = mod.object

            # Logic from https://blenderartists.org/t/blender-2-8-python-hide-unhide-objects/1141228/2

            if (not obj.hide_viewport and not obj.visible_get()) and self.select_hidden:
                # Hidden with the eye icon
                obj.hide_set(False)

            if obj.hide_viewport:
                obj.hide_viewport = False #  Toggle to test visibility

                if obj.visible_get() and self.select_disabled:
                    # Hidden with the monitor icon
                    obj.hide_viewport = False
                elif self.select_disabled and self.select_hidden:
                    # Hidden both ways
                    obj.hide_viewport = False
                    obj.hide_set(False)
                else:
                    obj.hide_viewport = True #  Toggle back

            if obj.hide_select and self.select_unselectable:
                obj.hide_select = False

            mod.object.select_set(True)

        context.active_object.select_set(self.extend)

        return {'FINISHED'}

def draw_item(self, context):
    self.layout.operator(SelectBooleansOperator.bl_idname)

def register():
    bpy.utils.register_class(SelectBooleansOperator)
    bpy.types.VIEW3D_MT_select_object.append(draw_item)

def unregister():
    bpy.utils.unregister_class(SelectBooleansOperator)
    bpy.types.VIEW3D_MT_select_object.remove(draw_item)

if __name__ == "__main__":
    register()

How to use :
How to run a script

Note that you would have to re-run the script every time you close and open Blender. If you want it to be persistent, make it into an add-on.
You can also add a shortcut to the operator by right clicking it in the menu.


You can find the FBX importer and exporter code in the addons folder:

Blender_Installation_Folder\Your_Blender_Version\scripts\addons\io_scene_fbx

On my system it's here:
C:\Program Files\Blender Foundation\Blender\2.74\scripts\addons\io_scene_fbx

More about paths in blender in different operating systems

By the way, you don't need to compile from source to see this code's source, since this is a python script (you can just download and install an ordinary package for your operating system).


How do I have create two Front Ortho Viewports with different reference images on each?

You can use "Local Collections" filters in each viewport to filter out your different backrounds.
Place each of your images in a different collection.
Place your work objects in a third collection.

Create 2 viewports by click-dragging the edge of the 3D viewport.
Expand the "N" panel, then go to the "View" panel, go down to "Collections" and check "Local collections" in both viewports.
Now click the eye icon of the background collections in each viewport.
Result :


Bending a mesh along spline which it's also following,not working

I don't know if this will work for what you finally want, but for what you described, I would simply use the curve modifier and then animate moving the object along the X axis. Here's what I did

add the cylinder, subdivide it, rotate it, apply rotation and move the origin, as you did.
add a Bezier curve.
in Edit mode, position the Bezier curve to create the path I wanted
add the curve modifier to the cylinder using X as the deformation Axis.

This will move the cylinder to the starting point of the Bezier curve.  Key frame it here.

Move the time to whatever is appropriate, move the cylinder along the x axis, and keyframe.


The option in that menu is for the viewport only. To achieve the same effect in a cycles render you must either enable the setting in the world tab of the properties menu.

The best way to do this would be to enable an AO pass, which should be enabled by default.

You can then composite the AO pass with your image and control the effect after you've rendered. This is usually the node setup I use to control AO when compositing.


Why bevels on a <90º edge are egg shaped, and not circular?

This seems to be working on current version. (2.91.0)


volumetric shaders missing in blender 2.69

Volumetrics have been added in 2.70, not 2.69.

Download the Release Candidate here: blender.org/development/blender-2-70-release-candidate

(A final stable version has not been released yet)


small white tracking box i cant get rid of

This is a tracking point used for motion tracking.

It is creating by pressing Ctrl + the opposite for your select button.
To get rid of it, simply select it and press X, delete.


SpaceProperties.context
This is the enum property that used to go across the top of properties area, rendered as tabs.

class bpy.types.SpaceProperties(Space)
Properties space data
context
        TOOL Tool, Active Tool and Workspace settings.
        SCENE Scene, Scene.
        RENDER Render, Render.
        OUTPUT Output, Output.
        VIEW_LAYER View Layer, View Layer.
        WORLD World, World.
        OBJECT Object, Object.
        CONSTRAINT Constraints, Object Constraints.
        MODIFIER Modifiers, Modifiers.
        DATA Data, Object Data.
        BONE Bone, Bone.
        BONE_CONSTRAINT Bone Constraints, Bone Constraints.
        MATERIAL Material, Material.
        TEXTURE Texture, Texture.
        PARTICLES Particles, Particles.
        PHYSICS Physics, Physics.
        SHADERFX Effects, Object visual effects.

In the python console
>>> for a in C.screen.areas:
...     if a.type == 'PROPERTIES':
...         break
...
>>> s = a.spaces.active
>>> s.context
'DATA'

>>> s.rna_type.properties['context'].enum_items_static.keys()
['TOOL', 'SCENE', 'RENDER',
    'OUTPUT', 'VIEW_LAYER', 'WORLD',
    'OBJECT', 'CONSTRAINT', 'MODIFIER',
    'DATA', 'BONE', 'BONE_CONSTRAINT',
    'MATERIAL', 'TEXTURE', 'PARTICLES',
    'PHYSICS', 'SHADERFX']

Setting the panels bl_context class property to a value above defines which "tab" it is in.
Trying to set an enum to an undefined value will throw an error, as opposed to setting bl_category in a 'TOOLS' panel which creates a new tab.
To make a new tab would need to somehow add an item whilst un-re-registering the property.  Perhaps this is doable, in the back of my mind there has been a question either here or on the blender artists forum.
The property is inter-twined with context.  I wouldn't mess with it.
Alternatives

choosing one of the above for your Panel context. Remember there is the ability to subpanel in 2.8 by defining a panels parent panel.
appending or prepending draw methods to existing panels. Prepending to a panel that is always at or near the top gives high vis easy access. IMO this is under-utilized.
"take out" (unregister) panel classes that you wish to replacce.  Eg overtake one of the conexts by unregistering other panels when in "armory" mode.
or redraw an existing panel.  Panels have a _drawfuncs list that can be manipulated at runtime.


Addon or featurs in Blender capable of profiling scene?

There are several ways, with which you can retrieve information about the imported objects in your .blend file.

The Outliner shows all object in a hierarchy in the scene. In Object Mode, the header will show the vertex, face and triangle count of all objects. You can select objects in the outliner and the 3D View.

Expand an objects hierarchy with the + icon. It will reveal a mesh datablock. Click on the mesh datablock to enter Edit Mode. In Edit Mode, you can manipulate the vertices, edges and faces in the 3D View. The header will now show the Verts, Faces, Tris count of only this selected object.

Scripted

You can load a simple script into Blender's Text Editor and execute it from there. The following script will write the name, vertex count, edge count and face count to a file which is specified in line 4. You will have to change the path according to your needs.

import bpy
import os

path = "U:/PWP/Desktop/info.csv"

with open(path, 'w+') as f:
    for ob in bpy.data.objects:
        v = len(ob.data.vertices)
        e = len(ob.data.edges)
        p = len(ob.data.polygons)
        tris = sum(len(p.vertices) - 2 for p in ob.data.polygons)

        f.write(ob.name)

        for data in [v, e, p, tris]:
            f.write(',' + str(data))
        f.write('\n')

Tris count added from batfinger's comment to this answer. Excluded in the table below.

The created csv file can be opened in various applications such as Notepad or any Office Suite.


Can I make video game clips from any game like Minecraft ones?

People can make Minecraft videos in Blender by importing characters+rigging and worlds and then animate and render them. For example this question has images that shows some of the process:
Cubic character armature deform
It's not like people are making screen captures of a game they played, then importing that video and applying a different skin/texture to the characters, that's not how it works. It would be the same as if you recorded a bit of Starwars and expected there to be an easy way to redress all the storm troopers to look like indiana jones.

Currently there are no easy ways to replace garments on recorded footage, but that doesn't mean there aren't complicated ways.
The literature
Ways are emerging to help automate the process of match making and garment replacement, but they are early proof of concept, and are not likely to be included in Blender any time soon (or indeed possibly never)


Import human from MakeHuman has modifier which has (robe, hair and penis) which should not be there


Try setting your camera Focal Length to a number in the range 20mm — 105mm and see if that helps.

Focal length = 1m is a very exaggerated setting and you've probably set it by mistake

Edit:

also, your clipping Start and End settings are weird. Start must be smaller than End, and End should be much larger: try 1 meter!

To summarise: it looks like you have messed up with your camera settings. Creating a new camera and deleting the existing one should fix your problems.


You had not applied the rotation to your object.  Since you had rotation amounts in each axis field, it caused the lid to rotate in the wrong direction when you tried dragging only one field in the properties tab.  It was causing it to rotate on the object's local axis.

You can apply the rotation by selecting the object in Object Mode, hitting ctrl-A, and selecting "Apply Rotation."  Now, if you use one of the fields to rotate the object, it will rotate as expected, on the global X axis.

As for the axis object that you wanted to get rid of, it turned out to be an empty in your scene, which looks like was the parent of the case objects.  Just delete that if you want, or, if you want to keep it, just hide it.

RBlong2us out!


Rigging - Sword like object influenced by 2 bones

If there's only to be one parent switch, the Child of Constraint should do that, but for multiple switches or just plain simplicity, I'd be looking at (as you mentioned) visually switching between two swords, or even easier - splitting the project up between two or more Blend files, each taking over from the previous and each with the correct parent assigned. (Ctrl+P)
The transition would be simple enough.  As the hand would firstly have to move to the sword's handle you'd need to animate that in the 1st file with the pelvis as the parent.  Once the sword handle is gripped, that would be where the next Blend file takes over and with that running, the hand is the parent.
A similar case is here:
How can I copy animation from an object while it was attached as a child and then paste that animation to it after detaching it?


If I understood your question, you have to combine two different materials into one, using the alpha channel to mix between the two shaders.

In my example I created a material for all the faces except the zone of the logo, then duplicated it, assigned the dupli version to the faces of the logo zone, then added in the dupli version a new principled shader, with the image as base color.

Then I used alpha channel to mix between the two shaders.


Snapping doesn't work properly with collection instances

You can only snap the Origin of Collection Instances.
I see this as design limitation that you have to work around. The Instance doesn't really know about its own geometry. You can however snap things to Instanced collections geometry.
Aternatively you can use linked duplicates with ALT+D, but you won't be able to one-click-select your group objects anymore unless you parent all but one objects to the last one and deactivate selection on these. But this is not always desirable.
I feel this kind of workflow is not ideal with the Blender toolset. You could try your luck in Vertex or Face Instancing with an object which you use as a parent to your instance collection.
It might help put the matter into perspective to reflect on the actual thought process behind Collections. They are not meant to be a modeling workflow, and they are more than a simple container, because objects and other collections can be part of an indefinite number of collections.
Collection Instances are a great way to reduce load on the hardware, and they can save a ton of clicks, but they definitely weren't designed to be used in an actual modeling workflow. They are great for scattering multiple instances of grouped objects, but you will have trouble actually placing individual ones precisely. I think we'll have to wait for either a big improvement in this regard or a new tool altogether.

To hide the source Collection, Click on the checkbox next to the eye icon in the outliner (top right of the screen). This will exclude this collection from the current view layer.
If you want it to disappear from the outliner altogether, right click on the source collection > Id Data > Unlink. You won't be able to modify it afterwards though (unless you're fine with the finicky process of re-linking it to the scene) so I wouldn't recommend it.
Or you can use it in another scene or another blend file and instance it in your current working scene but again this is more tedious than excluding from the view layer.


Convert a STL mesh object outline to a path (to trace the outline of an STL)

I found a workaround which may help others where grease pencil isn't needed but can be used if they want to.  Note: To use Grease Pencil Convert To Path it needs to be in 2D
2D slice (Good for copying threads from STL's to 3D print and if you want to use Grease Pencil - Convert to Path)
-Center Object pivot point and / STL to Origin
-Apply scale and Location object transform on STL / Object
-Create Mesh Plane (larger than object)
-Select Plane - Add Boolean Modifier
    Options - Intersect
    Object  - STL or Object
    Solver  - Fast

-Hide STL / Object (allows to see 2D section)

Extra: Can Select Plane and do a G - Z to see sections
Extra Extra: Can do in Geometry Nodes

3D slice (to view internals)
-Same as 2D Slice but change Solver to - Exact


The former Boolean bugs as soon as you have overlapping edges, vertices or faces, you need to use the Exact option in the new Blender version and it will work fine:


Alembic eye mesh not following the character body

Nevermind. I found the answer after spending my entire day to get that eye mesh. Solution was: My rig eyeball has the same naming convention and alembic dont read same name file so i had to separately export the eye mesh from maya to blender. And now its working:)


Mesh Deformer Modifier - Low poly mesh with softbody simulation deforming a high poly mesh

Parenting only effects the origin and the transforms of the object, never the mesh. There are two ways to achieve this however.
1. Lattice: you can use a lattice modifier, which can be given a softbody component
2. More practical: Mesh deform modifier. It's a bit cumbersome to set it up, but I'm sure you'll find help with that online.


You should add a Force Field. [Shift + A] -> Force Field -> Turbulence

Make sure it's in the same layer as the particles object you want to affect, to get the a turbulent flow of the type you linked.

It looks like what you did was add turbulence to the Particle System in the Force Field Settings tab, which makes each individual particle act as a force field (if you turn on Self-Effect in that tab, you'll see how this affects the particle system).

The Field Weights settings tab controls how much each type of force field affects the particles.


Why does Photoshop read my exported Blender 16bit file as 32bit?

Because 16bit EXRs are floating point, but Photoshop's 16bit format is integer.

Integers represent simple whole numbers, in the case of int16, pixels are values from 0-65535. Floating point uses a special representation, sort of like scientific notation. It's still 16bits per channel though. Floats are less precise than integers, but allow a wider range of values. This is often useful for visual data, since our eyes have a very wide dynamic range but are not terribly precise.

The problem Photoshop is trying to deal with is the lack of dynamic range. 16bit integer (int16 for short) has 2^16 values, so it has 16 stops of dynamic range. 16bit floating point (float16 for short) is able to pack 30 stops into the same 16bits by using its scientific-notation-like way of writing the values. In order to avoid smushing that dynamic range, Photoshop needs to import it in 32bit mode.

On a further note, I would advise against importing OpenEXR files into Photoshop. In most cases, it's best convert to a display-referred format first (like 16bit TIFF or PNG, which is integer btw) which better accommodates Photoshop's editing model. See this question for related info: Render with a wider dynamic range in cycles to produce photorealistic looking images

Additionally, Photoshop is not equipped to handle data within OpenEXR such as additional passes, z-buffers, etc. As you can see from it's confusing switch to 32bit (due to lack of float16 support), Photoshop is simply not designed around the sort of data stored in an OpenEXR. "Pre-chewing" the data using Blender's compositor or another scene-referred comp tool (such as Fusion or Nuke) will make life a lot easier.


To do it manually, in edit mode use L to select linked points and adjust the radius property which will be applied to all selected points. The radius property can be found in the properties sidebar N.

Or you can automate it with python. A curve object can have multiple splines, each spline then has multiple points. Note that bezier curves and nurbs curves use different property names for the points. For bezier curves it is bezier_points while nurbs curves use points.

import bpy
import random

c_obj = bpy.data.objects['BezierCurve']

for s in c_obj.data.splines:
    spl_rad = random.random()
    # change to s.points for nurbs curves
    for p in s.bezier_points:
        p.radius = spl_rad


How to delete face that doesn't have vertices

As indicated in comments, the face you're trying to edit belongs to a different object than the one you're editing.

The dark-orange outline indicates that there were multiple objects selected when you edited Edit Mode. If you try selecting multiple objects, you'll see that the last one is outlined in light orange, and all the others are in dark orange. That highlighting remains on the earlier objects when you enter Edit Mode.


This is math heavy.

So in this case, the only thing that varies, texel by texel, is the tangent.  The tangent is a vector that points in the direction of delta UV (well, either U or V, I can't remember.)  In order to represent this on a texture, you code how much the tangent has been rotated from a "base" UV map.

So start by making an additional, "straight" UV map.  Now you need to know the difference in the tangents between the two UV maps.  To do this you can use the arc cosine (math node) of the dot product (vector math node) of the tangent vector of each UV map (tangent node).  This will give you a value ranging from 0 to pi that represents the amount of rotation, but not the direction (clockwise or counter).

In order to determine the direction of rotation of the tangents, you need to create another vector.  Start by taking the cross product (vector math) of your two tangents, then take the cross product of the cross product vector and one of your tangents (probably the undistorted tangent).  The first cross product is a vector orthogonal to both tangents, while the second forms an orthogonal 3D basis with the undistorted tangent and the first cross product.  Now you can use the dot product (vector math) of this second cross product with your other tangent (from the distorted UV map) and evaluate whether it's positive or negative to determine the direction of rotation.  Putting this together, you can generate a value ranging from -pi to pi:

(dot(cross(tangent1, cross(tangent1,tangent2)), tangent2) > 0) * arccos(dot(tangent1, tangent2) - (dot(cross(tangent1, cross(tangent1,tangent2)), tangent2) < 0) * arccos(dot(tangent1, tangent2)

(What if any dot products are 0?  Or what if any cross products are 0 vectors?  Then that means that tangent1 = tangent2, and there is no rotation; it is equal to zero.)

If you remap this to the 0,1 range (add pi, then divide by 2*pi, math nodes), you can bake it to a texture on your undistorted UV map and you have an image map of the rotation of your tangents.

How do you use this texture to regenerate your anisotropy?  Load as non-color data from your undistorted UV.  Now rather than feeding this into tangent, you can use it directly as a rotation input for your anisotropic shader, which accepts input in the 0-1 range anyways.  Don't forget to use your undistorted UV map to generate the tangent vector.

Order of operations on cross product matters, and rather than getting into details regarding that, just be aware that you may have to invert your rotation depending on how you do it (rotation = 1 - rotation, subtract math node).

Once you do this, you can safely delete the distorted UV map.  Your rotation is coded on a texture, and you can access it with only 4 vertices.


Scripted scene building - where to begin?

This might get you started

BlendData.libraries
csv

import bpy
import csv

file_csv = ".../layout.csv"
file_components = ".../components.blend"

with open(file_csv, newline='') as fobj:
    reader = csv.reader(fobj)
    layout_table = list(reader)

required = set(col[1] for col in layout_table)

with bpy.data.libraries.load(file_components, link=True) as (data_from, data_to):
    available = set(data_from.meshes)
    missing = required - available
    data_to.meshes = list(required & available)

if missing:
    txt = bpy.data.texts.new("missing_components.txt")
    for comp in missing:
        txt.write(comp + "\n")

objects_data  = bpy.data.objects
objects_scene = bpy.context.scene.objects
name_to_index = {mesh.name: index for index, mesh in enumerate(data_to.meshes)}

def create_dupli(id, name, location):
    try:
        mesh = data_to.meshes[name_to_index[name]]
    except KeyError:
        return

    dupli = objects_data.new(id, mesh)
    dupli.location = location
    objects_scene.link(dupli)

for id, name, x, y, z in layout_table:
    loc = tuple(float(val) for val in (x, y, z))
    create_dupli(id, name, loc)


I guess it has to do with the Bool Tool which automatically switch the display of the boolean object you're using to Wire. Go in the Properties panel > Object > Viewport Display > Display As and choose Solid (or Textured)


How can i merge these two meshes without non manifold edges?

There are several ways you can go about doing this. If the two patterns must be part of one mesh for your purposes, the use the second two options, but if they don't need to be merged into one, then first option will probably work better in the long run and is nondestructive.
Parenting the Meshes
First, if you don't need the objects to actually be a part of the same mesh, you can parent one to the other. This will allow them to be transformed, keyframed, and animated as one object, but won't cause the problems of non-manifold geometry. This approach may also make texturing easier. You can parent them by selecting one mesh, hold shift and select the other. Then press ctrl+P and set parent to object.
Merge and Manual Editing
If the objects need to be part of one mesh, you can join them by selecting one mesh, hold shift and select the other. Then press ⌘+J to join the meshes. Once complete, you can go into Edit mode, ensure you have Vertex Select enables, and go to Select > Select All by Trait > Non Manifold. This will identify any Non Manifold geometry in you mesh and you may be able to fix it by hand.
Merge and Remeshing
You can also try remeshing the object once merged. Go to the Sculpting window and locate the Remesh option near the top. You can adjust the size of the new faces from here (based on Voxel Size). The smaller the Voxel Size, the more detailed the new mesh will be, but it will also take longer and create and object with many more vertices. This approach may also cause unwanted geometry between the two objects.
As mentioned previously, the first approach will most likely yield the most desirable results.


There are many video-tutorials for this topic on Youtube and (answered) questions here in BSE. To get you started I selected some of them for you:

How to Make Rust

Quickly Add Dirt to Crevices

Using Ambient Occlusion to add Grunge

Need to make (node setup) of realistic dirt/ grime/grunge on top of image texture of ceramic tiles


I suggest using custom transform orientations and a track-to constraint to get the cameras pointed at the faces. Please see the demonstration here: https://youtu.be/1Mu6loumKj0


Material in material preview window becomes pale

i would propose you change your shader nodes like this:

Don't use the transparent BSDF but the color for the first shader.
I just hope you don't need this transparency...
result in material preview:


How can I UV unwrap a mesh based on its 3D perspective in the viewport?

Enter edit mode
Select the face that you want to be unwrapped
Press U then choose "Project From View"
Note : "Project From View (Bounds)" will fit the UV to the texture space like the image down below


Why does the zoom sometimes stop at a point?

Explanation (Brief)

Blender's 3D navigation uses a central point to orbit around.

In practice this is good for modeling an object which you rotate about a lot to see from all sides(think of a potter using a wheel).
However this makes it awkward to explore a scene or model an object from the 'inside', for example.

There are some ways to use Blender without this being an annoyance. ... read on!

Explanation (Detailed)

Blenders view is constructed by 3 elements.

location: the point of interest that orbit when rotating the view-port (the center of the screen).
distance: the zoom level (distance from the location).
rotation: value for yaw-pitch-roll (around the location).

linked to API reference.

Typically users don't need to worry about this detail, however zooming will only change the distance which is an offset from location (where 0.0 is zoomed in as far as possible == no offset).

Solutions

Early on using Blender I was quite annoyed by this limitation, of course there are ways to set a new view-center, common way is to select an object and press numpad ., but what if there are no objects where you want to look at? .. or the object is very large? (a terrain mesh for eg). Sometimes I found myself rotating the view 90d, panning, then rotating back - which seemed an unnecessary workaround.

Here are some ways to navigate in large scenes or scenes with no obvious center...

View Dolly: CtrlShift + middle-mouse or Shift++/-works similar to zoom but translates the view center (like panning forward).I think this is the most direct answer to your question, but listing other methods too.
Walk/Fly Mode: ShiftFAs with dolly this can move the view back and fourth (using the mouse wheel), but you can also look around using the mouse and WASD keys, its a mode all on its own and has pros and cons which are better explained elsewhere.
Auto Depth (Interface Preferences): useful in combination with Zoom To Mouse Position, Using these will make sure the distance is always the value under the mouse cursor, this means you have to consider where you click when moving the view but can also be very handy since it gives you a lot more control.If you work with large scenes - like a game level for example, and want to move around a lot, I'd recommend to try these options. See this video for a demo.
Border Zoom: ShiftB: Also sets the center-point when zooming.
Center the view around the mouse cursor:AltFThis will take the position under the cursor and make it your viewpoint center.
Center the view around the 3D cursor AltHome
NDOF (N-Degrees of Freedom), also known as a 3D mouse, hardware you can use to navigate a scene with Blender, See devices made by 3dconnexion. Blender's 3D View supports this, allowing you to explore a scene. Walk/Fly modes also support NDOF devices.(Note, this is not a promotion of 3dconnexion, in fact there are very few companies who make such hardware, So currently Blender only supports 3dconnexion)


How would you create a cd material in Cycles?

Here's the fake iridescence effect I achieved. Try to experiment with Mapping and Anisotropic nodes settings.

Here's an animated gif (click on a picture below to see a larger version).


How to do texture painting on a character?

It sounds to me like you don't have your UV maps set up properly. Did you unwrap the model after shaping it? What you're describing is something I've had happen when Blender is still trying to use the UV map for the object I started with, when extensive modifications have made that useless. For example, paint appearing on two parts of the mesh at once suggests that you have portions of your UV map overlapping each other.

You have two options, I think: first, you could UV unwrap. To do that, go to the "UV Editing" tab with one of the pieces of your model selected, select the whole thing, press "U" and then click "Unwrap". It may result in a pretty bad map, so you may need to look up some tutorials on UV unwrapping. You'll also need to unwrap each piece separately, and it'll probably be easiest to use a separate image texture for each one.

The second option is easier but not as good for detail -- you could just vertex paint. For that, just switch from "Object Mode" to "Vertex Paint Mode"; I'd also recommend looking up a detailed tutorial on using Vertex Paint, though it's not terribly complicated.

Oh, and one more option: if all you want is a single color, all of this is overkill -- it would make much more sense to just change the material to one that uses the right base color.


UV Maps - is it possible to use the third channel (W?)

Looking into the Blender source code, the UV processing does not account for the third channel - so this is not possible within a single standard UV map. In order to store an additional (W) channel you could use an additional UV map - eg, 'UVMap1' could hold U and V while the 'U' channel of 'UVMap2' could hold the 'W' channel. However, this method does not provide a simple method of manipulating the UVW map (since the W channel needs to be manipulated separately.

That said, by considering the two UV maps as a 'front view' and a 'side view' of UVW space we can achieve a similar effect - but you need to be careful when manipulating the UV maps to ensure they stay consistent.

To demonstrate, start with your initially unwrapped mesh - a standard UV map :

Copy the UV map (click the '+' alongside the list of UV maps in Edit mode) and rename them to make it clear that one is the UV "front" view and the other is the 'WV' "side" view. 'Select all' (A), scale to zero in the X-axis (SX0Enter) and select everything and move it to the size (GX then drag to the side). You should now have something like this :

Now to move points into the W dimension you can simply select them (or select a whole face) and drag them along the X (U) axis with GX.

To combine the separate 'front' and 'side' UV maps into a UVW map you simply need to separate the channels and re-combine into a single UVW vector :


creating n random points on face of mesh

as it is written bpy_extras.mesh_utils.face_random_points(num_points, tessfaces) takes tessfaces not faces and to get access to the you'll have to calculate first :

obj = bpy.context.object #Gets the object
me = obj.data
me.calc_tessface() # recalculate tessfaces
tessfaces_select = [f for f in me.tessfaces if f.select]
bpy_extras.mesh_utils.face_random_points(400, tessfaces_select)


The object looks like a shirt. It has it origin centered, I can tell from looking at the transforms. Technically the object is centered. The problem is that the rotations aren't matching, Blender using the Z axis up, and marvelous designer apparently uses the Y axis as up. If you rotate the object on the X axis 90  or -90 degrees it should line up.


Why are there fewer objects when I use “dyntopo” to sculpt small objects?

I found my own solution to the problem.Increase the value of resolution...


Duplicate and slide edge (rip from boundary)

Select the edge on the border and add a loop cut there. Since usual Loop Cut And Slide tool (Ctrl+R) won't do in this case due to 5-pole, use Offset Edge Slide instead.

This way will create triangle after cutting and sliding along edges which compose 5-pole, small  cleanup is required there to merge one vertex to another.

See Offset Edge Slide in manual.

As mentioned in comments by @Leander, Offset Edge Slide indeed has options you can enable while executing it. Like Loop Cut and Slide, it provides:

Even mode which matches the shape of the created edge loop to existing edge loop from one side;
Flipped option which controls which edge loop will be taken into account by Even mode;
Clamp which allows to toggle limiting to existing edge loops.


Molecular script addon permanently stuck in simulating state

Add  "free bakes" to Quick Favorites  and "process simulation left..."
At view port just press Q and menage simulation from there.
Good luck


How to check how much GPU memory is used by object?

Objects like trees or toothbrushes take up much memory.
For trees, even games use object instancing. While copying the tree, use Alt + D. This will keep you from editing the trees individually but will keep the memory requirement low, you can also have a few trees and create an illusion by rotating them, (fake it!)

Too many leafs will unevitably result in high memory need. I strongly recommend you to take a look to this cycles instancing test.

If you don't want to lower the details, you can try caching the required files on your computer(cycles only). To do this, you need to use the (Cache BVH) checkbox under the "performance" section of render tab.
User preferences also let you to adjuct the available RAM to use.


Make a new Custom Transform Orientation per object, and name them to match. You will then be able to choose the custom transform as you also choose  Global/Local/Normal/etc. Object Mode deals with the object as a whole, so it won't give a good result using Normal for instance, where you might use that in edit mode as you make selections of individual elements of the object mesh.


How to make an object transparent in the viewport?

One option is to set the alpha value (fourth component) of Material.diffuse_color:

float array of 4 items in [0, inf], default (0.8, 0.8, 0.8, 0.8)

import bpy

# Get the object in context
obj = bpy.context.object

# Get the active material
mat = obj.active_material

# Set the alpha value of the diffuse color
mat.diffuse_color = (0.0 , 0.0 , 1.0 , 0.7)


How can I change Blender's output image resolution?

For texture backing the resolution of the target image is what's important. The first step for baking is to create a new image in the image viewer were the normal map will be stored.  Here you can set your desired resolution.  If you use cycles, you need to add the texture node to the material of the object you want to bake to and select the image you just created. Next you can go to the bake settings in the render tab, mark selected to active. Make sure you select the objects in the scene, the one that you want to bake to needs to be selected last (it has a bright orange outline). Then you can press the bake button and once it is finished, save the image from the image viewer.


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.


How to create a flat base to a photogrammetry model in Blender?

What I do usually is profit from the new vertex group options for generated geometry in the solidify modifier from version 2.83+.
First let's say we have an ocean modifier on an object.

Create a new vertex group.

Add a solidify modifier, set the Shell Vertex Group to your new group, and the Thickness to 0. This will effectively duplicate your geometry in place.

Now add a plane at the altitude at which you want the bottom of your foundation to be. Scale it so it is larger than your terrain.

Add a shrinkwrap, set the target to your plane, vertex group to your new vertex group, set the mode to project on the Negative Z axis. Hide your plane.

Now add a new material for the dirt/soil, assuming the first one is your photogrammetry raster info.

Get back to the solidify modifier and set the material offset to 1. Result :

With "proper" shaders:

Note : The geometry will be ugly if viewed from upside-down but what you can do is check "Only rim" in the solifidy modifier to only keep the rim of the object.


Possible to bake boolean difference or use "exact" only when "fast" fails?

You can add both booleans, but disable the exact boolean. Then, you can keyframe their toggles on frame 0, by hovering over the buttons and pressing I. Then, you can go to the first frame, where you need exact boolean, toggle between the booleans, and again use I to keyframe them. Then on the first frame after that, where you no longer need exact, you can again toggle them and keyframe them, and so on.


Mirrored simple colored material doesn't render while BGE game

This is problem with normals orientation.
Object is composed of multiple non-manifold meshes. There is one selected on the screenshot below and moved away, it's a wall while as I understand windows were left in place:

In this case Blender won't distinguish what is inside and what is outside so recalculating won't work here. Best solution in the long run is to remodel. This would allow easier selecting, adding details if any etc.
Fast and dirty solution though, if time is important and if the building isn't going to be visible from inside or from close distance, is to flip normals manually in places where you want them to be inside. Select a face, run Select Linked (Ctrl+L) and flip normals inside. You can enable Backface Culling in the Properties shelf to see which faces require repair.


To merge the legs with the torso, select the two objects (the legs and the torso) in either order, and press CTRL-J key. The object you select first gets merged into the object you select last, so if the first object you select is the legs, and the second is the torso, the surviving object is the torso. If the first object you select is the torso, then the surviving object is the leg object.

But why do you want to merge the legs with the body? In blender, for one element of a character (like a leg or an arm) to articulate relative to another element (like a torso) the elements need to be separate objects. After merging (or "joining") the legs to the body, moving the legs relative to the body (or the body relative to the legs) becomes impossible with ordinary modeling and animation techniques. So, if you're modeling a non-movable statue, go ahead and join the objects. If the character is to be animated, leave them separate. In fact, if the character is to be animated, you probably want to separate the legs into four objects, one object for each of the lower legs and and one for each of the upper. Similarly, when you get there, if the feet and hand are to be able to articulate, each foot and hand will need to consist of multiple objects, depending upon how detailed you want the animation to be.

To preserve the ability to animate the character, you would use a different mechanism in Blender: you'd parent one object, for example an upper leg, to another object, the torso, and in turn, parent the lower leg to the upper. There are several tutorials available on Youtube easily located by using your favorite search engine with the parameters "Blender tutorial parent objects".


Not unflipped normal but some faces are unusually brighter?

I figured it out. I had left some faces detached from the same-object mesh. How could I do that!
All I had do to was to merge vertices of the loose faces with the vertices in respected positions. The edges of the  loose faces were positioned just beside other edges of the larger mesh. So visually, there were two edges side by side. Merging vertices solved the problem.


Is it standard when creating a 3D game model to only use one mesh?

Copying a couple performance tips from this thread —

Reuse geometries and materials whenever possible
Use instanced geometries for faster mesh instantiations
Merge meshes when possible

The main thing is that the more meshes and materials you have, the more draw calls you are making to the GPU, and you'll get worse performance than if you were drawing the same number of triangles using fewer meshes. Performance considerations in e.g. Unity may be a bit different, where the engine is probably optimizing your model somewhat for you.

If you're having issues exporting animation, that's probably unrelated: there are a fair number of open bugs about animation in the three.js Blender exporter. May have better luck exporting FBX or glTF (with either of KhronosGroup/glTF-Blender-Exporter or Kupoman/blender2gltf) before loading in three.js.


Why is the shoulder moving when I move the left forearm bone?

Select the mesh, activate the two little buttons on the armature modifier so that it shows its effetc also in edit mode, then move the forearm in pose mode. Back to the mesh in edit mode select one of the vertices that is movin weird: in the "N" properties panel you will see that they have some weight from forearm bone (maybe 0.000001) and expecially from the f_pinky03.L bone: thoose weights are causing the unwanted deformation. So select all the weird vertices and remove all weights to have everything fine.

Remember that even a very tiny weight, if it's not "balanced" by another bigger one, will cause a big movement, because Blender does an automatic normalisation between all assigned weights.


In [version_number]/scripts subfolder of your Blender installation, or in any additional path(s) for scripts you've set in User Preferences, there's a folder templates_py (and one for osl too). Just put the templates there; in the menu, each _ in the file name will be converted into a space and each beginning letter of a word capitalized.


How to know the name of the an active preset dropdown?

Thanks to @AFWS

print(bpy.types.CYCLES_PT_integrator_presets.bl_label)

active preset is in fact the name of the bl_label


you are using a separate timing for the playback ( time line ) and the render ( render tab ) you have two options to render the frames you want :

1- Keep the timing separate and set the render timing in the render tab :

2- Use the same timing for playback and render by disabling the alternative time range and set the time from either the render tab or the time-line


Exporting .mtl (with .obj) and multiple textures

Wavefront doesn't support multiple textures. You can only add one diffuse/specular/normal/... texture per material. To export both, you'll need to bake them together to one texture.

See the specification here: http://paulbourke.net/dataformats/mtl/


How to move object to a global position using hotkeys?

When moving an object you can type in measurements that are distances from the current location of the object to move. Similar options are available for scale and rotate.

With 2.70 we also have an advanced input mode which lets us use some basic python to calculate the distance with something like sin or pi. I don't know of any access (yet) to the current global location to use in this calculation.

So to set the global location of an object you need to edit the object properties.

These are also available in the properties sidebar (Press N) of the 3dview.

If you have a python console visible you could also alter the active object by typing in C.active_object.location.x = 0.0 or C.active_object.rotation_euler.y = 0.0 You can also access any object by name with D.objects['Cube'].location.x = 0.0

C and D are predefined variables in the blender python console C = bpy.context and D = bpy.data


Set the Output to "AVI JPEG" in the render settings.

Also , to set the place where it is saved , Click next to "/tmp/" , That folder image. Then select where to save. After doing all these steps you can then render and it will appear where you saved it.
UPDATE:
One of the big changes in 2.79 is that they finally separated containers and codecs.
The encoding options from previous versions are still there, but now they have organized differently
If you select FFMpeg video, there will be a new tab for Encoding options.

There you can select the container and the codec for the output file.
Container is the file format for the file, (Mov, Avi, Ogg, MP4, to name a few) sometimes is referred as a "wrapper".
Codec (short for Compression-Decompression) Is how the image is compressed. The picture quality, file size and processing power needed to view the file are largely determined by the kind of codec used and the settings used for it.


Thanks to batFINGER I've found the answer

import bpy
from mathutils import Euler

for area in bpy.context.screen.areas:
    if area.type == 'VIEW_3D':
        area.spaces.active.region_3d.view_rotation.rotate(Euler((0, 0, 0.01)))


Hairs of particle system on wrong places

The origin point of these buildings are not at the center of the building's base.

Place the 3D cursor at this base, for instance snapping it to the selected base
Then in object mode, choose 'object/transform/origin to 3D cursor'

To say it another way, objects as particle instances are moved/placed so that their origins are following the particle.


How to Keymap a Custom Operator with Properties

I believe the .axis appended to the end of the .new() constructor may be throwing your solution - it's being seen as an attribute of your keymap's properties, rather than referencing an idname for the operator which I believe is in your case
armored.zero_vertex
Here is an example of an implementation of a custom keymap applied to a hidden operator. It might be useful for reference:
The class definition surfaces the custom/hidden operator with its bl_idname
# Surfacing the Operators
# They can now be looked up via their bl_label attribute with the search function on default hotkey F3

class PREFERENCES_OT_toggle_emulate_3_button_mouse(bpy.types.Operator):
    bl_idname = "preferences.toggle_emulate_3_button_mouse"
    bl_label = "Toggle 'Emulate 3 Button Mouse'"

    def execute(self, context):
        context.preferences.inputs.use_mouse_emulate_3_button = not context.preferences.inputs.use_mouse_emulate_3_button
        return {"FINISHED"}

And then the keymap is applied:
km = wm.keyconfigs.addon.keymaps.new(name=idname, space_type=space_type)

kmi = km.keymap_items.new(idname, type, value, ctrl=true)

properties = kmi.get("properties")

for name, value in properties:
   setattr(kmi.properties, name, value)

keymaps = keymaps.append((km,kmi))


Is there a way to control master volume in vse?

There's a setting under scene data properties, here:

I never used that, but I think that even in VSE, some scene setting could be relevant... I just tried and it seems to work...


Strange shading on faces in Blender 2.8?

The "odd shading" is shadow from your lamp.

Try moving your lamp lower and forward some.


The greyed parts of texture are the parts with high reflection, so they reflect black background and this cause this effect.

Glossy shader is connected to bottom input, so value 1 in Fac slot make material pure glossy, value 0 is pure diffuse. This values are stored in texture as a colors: 1 = white, 0 = black.

What do you need to do is change white to grey, so from value 1 to smaller one.

One way how to do it is plug ColorRamp node between texture and Fac slot on  Mix Shader Node.
Now you can control values by colors. In this case you need to change white to appropriate gray = change value from 1 to less than one.

Also you can moving slides closer together and adjust contrast.

As second - for nice reflections you need something to reflect. Usually hdri environment map. You have black environment in your scene = black color in reflected from your materials = ugly grayed reflections.


How to extrude objects during game play?

Depends on what you mean with "extrude".

In terms of mesh-editing the answer is no. This is simply because you can't add faces to meshes from within the BGE.

As this does not help you with what you want, I suggest to get rid of the "extrude face" idea towards an "extrude effect". It does not add faces, but deforms the mesh in a way that it looks as it would do that.

There are several ways to achieve that:

armature deformation -> it can animate scaling too
shape key deformation
scaling animation -> would effect the complete mesh
mesh manipulating via Python (not a simple task)
adding objects
...

Without more information I can't tell what option is sufficient with your situation.


Rigid Bodies copied from one file to another don't work

There are a couple of topics in this question actually, so I'm going to cover them separately.

Copying Rigid Bodies objects between files

As you did, copying is simple as Ctrl C and Ctrl V.

In my case (running 2.77 RC1) when you paste the objects they keep the highlighted green.

What this green means is that the object is assigned to a Group. When working with Rigid Bodies, Blender add them to a group named RigidBodyWorld automatically. This is the way Blender knows what objects are into the simulation.

If you don't have your objects in the group, add them manually.

In case that you don't have Rigid Bodies working simulations into your scene:

Select all the objects you pasted
Press Ctrl G
Go to the operator panel (at the bottom of the Tool Shelf) or press F6 and change the name to RigidBodyWorld.

If you have other working Rigid Bodies into your scene, add them to the existing RigidBodyWorld group:

Select all the objects you pasted
Also select one of the existing Rigid Bodies in your scene, having this last object as the Active Object.
Press Shift Ctrl G
Select RigidBodyWorld on the pop-up menu.

Making your Rigid Body World work

Now, you have all the objects into the RigidBodyWorld group and they have all they Rigid Body properties as they had in the file where you copied them. But, if you are into a scene with no simulations, they'll don't work.

When you add a Rigid Body, Blender creates a Rigid Body World automatically, but if you are copy/pasting objects between scenes, you have to active the Rigid Body World manually.

Into the Properties window, go to the Scene tab and look for the Rigid Body World panel. Activate it.

Click the Group Field and select RigidBodyWorld

Now, if you play animation, you'll see that your Rigids Bodies are working just like in their original file.

Simulation VS Animation

Just a clarification: when you paste Rigid Bodies, you are not copying their animation because there's no animation linked to them.

Animation stores within an object as keyframes, and simulation does by caching. The simulation cache is a group of files that stores the transformation of the objects in every frame. Contrary, the keyframes just store this information in some frames and Blender interpolates the movement between them.

So there's no way to copy the simulation itself into a new file by pasting the Rigid Body objects until you convert the simulation into keyframes by Baking the simulation. Here there's a question which covers that: Baking rigid body transformations


Quick answer: Yes it does.

I set up a simple scene to test this.  Cube scaled up be 10, set as the Fluid Domain.  Added cylinder set as Fluid Inflow.  I then baked, and it dripped out of the cylinder, landing on the bottom of the domain.

If you would like, here is a .blend file with my test scene, however you may need to bake the fluid sim again (should take about a minute):


You should begin with less edge loops. Also, use the Mirror modifier as the hat seems rather symmetrical. Now you could do it with some extrusions, but maybe it's better to keep concentric circle to have a better topology. So enable the Proportional Editing option, drag up some vertices and edges, then inwards. At the end, add a Solidify modifier to give thickness, and a Subdivision Surface to smooth it.


How to scale objects along the length of a curve and keep them all facing the same way

As far as I know you will either be able to scale them progressively or orient them correctly at once, not both.

Using the arch as duplifaces in an arrayed plane you get correct orientation always facing one axis but no scaling.

You can then make duplicates real and clear any erroneous rotations introduced by the curve modifier.

Then scale them by hand or using proportional edit as desired.

Otherwise use the the array directly on the arches. It will not orient them correctly, but you can control scaling point buy point through the curve radius property.


How can I Copy and Paste the form to another object?

If at any moment you want to change the mesh of an object for another one (here for example you want to switch from the cube to the cone), select the object, go in Object Data and in the top dropdown menu (Browse Mesh Data) select the mesh you want:


convert sverchok script node to script node lite

I found conversions other users have performed, and diffed the two versions to check the changes they made. They only seem to change the syntax of the input/output in such a way that sv_main is no longer used:

every item in the lists in_sockets and out_sockets is now defined at the start inside bracketed (""") comments with the commands in and out
after the in / out command the variable name is given, followed by the variable type
the in variables also get a d default value, which was in sv_main before, and an n value of 1 or 2
if the default value is [] then n=1 otherwise n=2 (I dont know the meaning of this)
all code in sv_main is just executed at the end of the script and the def and return lines are just deleted

For instance
in_sockets = [
    ['s', 'maximum branches', npoints],
    ['s', 'branch length', dist],
    ['s', 'minimum distance', min_dist],
    ['s', 'maximum distance', max_dist],
    ['s', 'tip radius', tip_radius],
    ['v', 'tropism', trop],
    ['v', 'End Vertices',  verts_in],
    ['v', 'Start Vertices', verts_start]
]

def sv_main(npoints=100 , dist=0.05, min_dist=0.05, max_dist=2.0, tip_radius=0.01, trop=[], verts_in=[], verts_start=[]):
    out_sockets = [
        ['v', 'Vertices', [verts_out]],
        ['s', 'Edges', [edges_out]],
        ['s', 'Branch radii', [rad_out]],
        ['s', 'Ends mask', [ends_out]],
        ['m', 'Leaf matrices', mats_out],
    ]
    #some code
return in_sockets, out_sockets

Is converted to
"""
in npoints s d=100 n=2
in dist s d=0.05 n=2
in min_dist s d=0.05 n=2
in max_dist s d=2.0 n=2
in tip_radius s d=0.01 n=2
in tropism v d=[] n=1
in verts_in v d=[] n=1
in verts_start v d=[] n=1
out verts_out v
out edges_out s
out rad_out s
out ends_out s
out leaf_mats m
"""
#some code

I took these code snippets from a sverchok script by elfnor, so thanks to her for the example!


2.8 Eevee Composite Object over background lacking Transparency

You have to tell Alpha Over what is transparent - black in the Jupiter .jpg image is set to be transparent in this example and ColorRamp helps adjust what is transparent and what is not. The Transform node is for the position and scale of it.


How to acces all objects via Python in the Game Engine?

You can access all objects from the scene by its name:

import GameLogic
scene = GameLogic.getCurrentScene()
obj=scene.objects['ObjectName']

To access the vertices:

import GameLogic

scene = GameLogic.getCurrentScene()
obj=scene.objects['Cube']

mesh = obj.meshes[0]

for v in range(mesh.getVertexArrayLength(0)):
    vert = mesh.getVertex(0, v)
    print( "%d,%d,%d" % ( vert.x, vert.y, vert.z ))

print( dir( vert ))


Blender 2.8 Beta will not run on Linux Mint.

sometimes blender quits before being even fully loaded or just not responds and for this behaviour You may try to access the folder where blender executable file is and run './blender' or 'sudo ./blender' or if You have blender installed as package just run straight these commands without searching for path to blender exec file. If there's an issue it will be printed in terminal. As an example, one instance of Blender not working in Linux Mint was an unsupported video card, or your computer not having the latest installment of (OpenGL 3.3) installed.


You don't need anything bound to the armature but the body parts which need bone deformations. So eyes and teeth could most likely be parented (or Child Of constrained) to bones, rather than being skinned with automatic weights. In fact, you likely wouldn't want the eyes skinned in any case. Depending on how your rig is built, you will likely want eyes parented to eye control bones so that their orientation can be changed easily.
Note regarding parenting vs. skinning of the eyes: If you want the eyes controlled by bones that exist within your main armature, and don't want to use parenting or constraints to do it, then technically, you CAN bind them to the armature. But if you do this, the eye objects will need vertex groups. The name of the vertex groups must correspond to the name of the bones which will control them. The eyes technically don't even have to be separate objects from one another. They can be two joined spheres, provided they have unique vertex groups, with only the vertices for each eye assigned independently to each of those vertex groups. The eye bones will find the spheres if their vertex group names are the same as those bones, and control them. The important thing is to have only one vertex group assigned to ALL of the vertices for each eye (meaning no other vertex groups exist for the eyes, and so no other bones will ever influence the eye geometry). Then your eyes will move as if they are directly parented to the eye bones, even though they are technically bound to the armature in the same exact way that any other "skinned" mesh is bound to the armature. But the bind behaves as if it is a direct parenting relationship. Meaning rigid. This behavior results from only having one vertex group involved. If only one vertex group exists on an object, then only one bone can ever influence the vertices for that object.
Note on unjoining objects with modifiers: Whenever you unjoin objects, they keep all prior existing modifiers. These modifiers will now exist for ALL newly separated objects. This includes armature modifiers. Simply make sure that you only have the modifiers you need for all your objects as they now exist. Strange things can happen if you have the wrong modifiers in place, and the resulting issues can be hard to track down, since you might not be thinking of this separation step as a possible cause.


To view the deformation by an armature in edit mode you have to check the two options of the armature modifier (1) Display modifier in Edit mode (2) Adjust edit cage to modifier result. They're located next to the visibility icon. This allows you to edit the mesh in its deformed state. – Leander Sep 18 at 10:14


As pointed out int he comments above, you don't have the entire stem of the glass selected. To select it all, press Z to enable wireframe view. This will let you select through the mesh as well, not just what you can see. Then use the box select tool with B to select everything you want. Change back to solid view again with Z and the scaling will work as you expected.


My project just stop working after a while

Well, nobody answered, but that's it.
I abandoned Blender 1.9 and I get back to Blender 1.83
now everything is perfect.


I believe that this is because of two reasons.

You'll want to increase the Draw Path Steps (should match particle Steps in particle settings for view port hair to match rendered results) to add more detail while you comb. Draw Path Steps is found in the Tools Panel while in Particle Edit* mode.
Make sure that Deflect Emitter is on in the tool panel while in
particle edit mode and set it where the hair no longer collides.


This is a great question, and had to think about it, but I think I have a simple solution:

Go to Draw Mode
With the box tool draw a rectangle at any location and orientation you want in the 3D Viewport.
Hit Enter to confirm the box location, orientation, size
Optional: change your view so you can understand this technique is not dependent on world view
Enter Edit Mode
With the Selection Tool active set the Selection Mode to Select Only Points or Select all Stroke Point

Select the whole rectangle you just created

Now switch the Cursor tool

With the Cursor tool selected go to the tools Settings and and set the Transformation Orientaion to Local

From the 3D Viewport Menu chose Grease Pencil > Snap > Cursor To Selected (you can also use the shortcut key: Shift + S  )

Go back to Draw Mode
Draw with any tool on the rectangle and then move your view to see that the strokes are in the same drawing plane.

You can see the drawing plane by turning on the 3D Canvas in the Viewport Overlay (In the Edit Grease Pencil section, put a checkmark next to Canvas to turn it on)


UV Maps not preserved after Boolean Modifier

take a look at this , I have had the same problem : Using Boolean Wraps texture awkwardly

they answered by saying i have to use the "Knife tool" Or knife project . The boolean should heavily be avoided , especially when you have already textured your mesh because it adds un necessary edges , doubles and vertices .


Physics Animation Sequence with Transparent Plane

Film tab appears with Cycles Renderer (here v2.79a):

The "Transparent" option in Film tab is for the background only. For any mesh to be transparent as well, you have several options. Make sure you select RGBA in the PNG options in order to include the transparency.

define the material to be transparent:

uncheck the object from rendering:

make it invisible to camera:

I am sure I am missing some other means! Note that all those methods may have side effect like shadows etc.


Object appears transparent in render but not in viewport

When you use the tracking feature, blender sets the compositor up using three layers:

One Layer is the movie, on layer is the objects you want to add, and one layer is the shadow/ao layer to project the shadow and ambient occlusion from the object to the background(movie).

As I can see from your nodesetup, the cubes are only visible on the background layer, but not on the foreground layer. Meaning you see the shadows and ambient occlusion but not the object iteself. Thus you have to

either adjust the visible layers in the render layer setup
or move the cubes to a layer that is rendered to foreground (probably the first layer, the second layer usually includes a plane to cast the shadow on)


Object texture not showing up when selecting "texture" viewport shading

Found the answer:

When using Blender Render, you only need to UV unwrap an object and add a picture to make it show up in texture viewport.
  When using Cycles, you need to do as in BR and then add a material, go to node editor and add an image texture. Select the picture you UV unwrapped the object to, and without connecting the node anywhere, the texture shows up in viewport texture mode.


fSpy importing camera into an existing scene

"It seems relatively easy" indeed, but it helps if you take some time to explore the real power of f-spy.
The first piece of information you need is the lens focal length and camera sensor size used to make the original image. Without it is going to be hard to get accurate placement.
Unfortunately f-spy wrongly labels "focal length" settings for Sensor Size
You might need to refer to a Lens to Field of View calculator (there are many on the internet) to get the field of view for your lens in degrees (not in mm)
The second part of the puzzle is working with real measurements, fSpy will not guess them for you.

Then, manually move the 3 axis tool in f-spy to set the origin and alignment of the scene: the white dot will determine the placement for the "floor" on the blender scene.
Without any real measurements there all you will get from spy is the  field of view on an arbitrary scene with arbitrary scale and relative distances, making it harder for you to approximate existing elements in blender.


You have set your keyframes to be 'Protected'. Click the padlock icon next to the 'Rotation' channel to unlock the keyframes so they can be edited.


The Exact solver option will be introduced with the release of Blender 2.91 as documented by the release notes. The design task for the boolean redesign was T67744 and the commit that introduced this to the master branch rB9e09b5c418c0a436e3c84ccf38c065527988b0a0.
The release of Blender 2.91 is planned for the end of November 2020. You can download the daily builds of the beta version from builder.blender.org.


Two perpendicular faces are highlighted as one (upon selection)

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

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


How to preserve measurements when manipulating an object

after applying the array modifier seperate the object :

in edit mode hit  P and select seperate by loose parts
set the origin to geometry for all objects
for the side objects set the origin to the side faces

scale all to induvidual origins


You can just use a nurbs path (or any curve) with a curve circle as a bevel object...

Model the curve into place, and choose the circle as the bevel object in the curve>geometry properties and adjust from there.


If you decrease your Subsurf subdivisions (View and Render) down to a value of 2 this will fix the problem, I guess a high subdivision creates additional faces that try to smooth but actually mess with the topology.


How to update 2d-shader coordinates when camera moves

Edit: as I wrote all that is below, I just realized the question was explicitly about 2D shader...
You just missed to call
self.update_region(context, None)

from inside the callback, which is itself called at each drawing.
Though, as it is the calculation is not correct. You should use object world matrix (see the previous answer).

Previous answer (I don't delete it as that could be useful):
As you want to move during the operator, you are in 3d, use:
gpu.shader.from_builtin('3D_UNIFORM_COLOR')

instead of:
gpu.shader.from_builtin('2D_UNIFORM_COLOR')

Also, in this case, use POST_VIEW, as indicated in the documentation.

draw_type (str) – Usually POST_PIXEL for 2D drawing and POST_VIEW for
3D drawing. In some cases PRE_VIEW can be used. BACKDROP can be used
for backdrops in the node editor.

self._handle = bpy.types.SpaceView3D.draw_handler_add(draw_callback_px, args, 'WINDOW', 'POST_VIEW')

One shader is needed.
You can start from object axis and convert them in world space:
def draw_callback_px(self, context):

    obj = context.active_object
    mat = obj.matrix_world

    shader = gpu.shader.from_builtin('3D_UNIFORM_COLOR')
    shader.bind()

    bgl.glEnable(bgl.GL_BLEND)
    bgl.glLineWidth(2)

    origin = mat @ Vector((0, 0, 0)) #Convert coordinates in world space
    x = mat @ Vector((2,0,0))
    y = mat @ Vector((0,2,0))
    z = mat @ Vector((0,0,2))
    batch_X = batch_for_shader(shader, 'LINES', {"pos": [origin, x]}, indices = ((0, 1),) )
    batch_Y = batch_for_shader(shader, 'LINES', {"pos": [origin, y]}, indices = ((0, 1),) )
    batch_Z = batch_for_shader(shader, 'LINES', {"pos": [origin, z]}, indices = ((0, 1),) )

    shader.uniform_float("color", (1, 0, 0, 0.2))
    batch_X.draw(shader)

    shader.uniform_float("color", (0, 1, 0, 0.2))
    batch_Y.draw(shader)

    shader.uniform_float("color", (0, 0, 1, 0.2))
    batch_Z.draw(shader)

    # restore opengl defaults
    bgl.glLineWidth(1)
    bgl.glDisable(bgl.GL_BLEND)


My Environment texture is displaying as a fully spherical texture

Make sure the aspect ratio of your environment texture is 2:1.  It seems to me that this is the reason for the massive distortion of your background.


Problem with animating 6 objects combined into 1

You should have to do it with separated bullets (objects).

This is my solution for your particular flow:

Create a shape key and you can animate that shape key.

See the image below:


I am new to blender and when I sculpt it isn't smooth like in videos I have watched

On the Tool panel (on the left of your 3D View, displayed with T), have you tried to:

Decrease the Detail Size?
Enable the Smooth Shading?


Batch rename objects with number sequence?

import bpy

for i, obj in enumerate(bpy.context.selected_objects, 1):
    bpy.context.scene.objects.active = obj
    obj.name = "object" + str(i)

Just replace "object" with "your name" and run this in the text editor (make sure you have all objects selected that you want renamed).


Make an object always the same shape as another but thicker?

You can try the Displace Modifier for static meshes, with no texture assigned it will simply offset a mesh for the specified distance.

It looks like you need something different though, so try the Shrinkwrap Modifier, with an Offset value.


I want to texture parts I have modeled in CorelCAD

Your immediate concern

You want to unwrap the model but when you unwrap a model by default it is trying to give you what it thinks is the best two dimensional projection it can for the model you provided.

If you want to have the wood grain aim a certian way you will need to manually rotate the UV "Islands" in the uv editor to match the orientation you want. You may also need to scale or translate the islands so that the grain looks the same size etc.

Selection of Individual UV Islands

By default, the UV editor will only show the UV map for faces that you have selected in edit mode. This can be used to your advantage.

Select the faces that you want to have the wood grain oriented in a particular way in the 3d editor window.

Select the areas you want to modify in the uv editor. To have the effect you want, you will need to select whole faces.

In uv editor window and you can use R to rotate, S for scaling and G to translate the UV islands in the image editor.

You can choose from several "uv selection modes" in the uv editor, but the default is vertex so I will assume you are using that mode.

If you select only faces you want to rotate at once from the 3d view, you can use A in the UV window to select the UV islands for them.

You might also find CTRL + L useful. This shortcut selects every visible "linked" piece of geometry. It works in the 3d view or on the UV editor. So if you select one of the vertices in the uv editor and press that combination of keys, you will select all the linked UV islands.

Final thoughts:

Blender is very useful and fun software but it does have some learning curve to it. It sounds like you might be new to UV editing in blender as well.

In addition to this answer I'd recommend looking for some tutorials on the topic because they might help you in the long term.

Blender Guru (AKA Andrew Price) has a tutorial in some of his begginners series that is pretty useful for understanding some of how to unwrap particular kinds of geometry.

Here is a link: Begginer UV tutorial


This is not at all a "physically accurate" simulation by any stretch, but it may be able to approximate the desired effect with a bunch of modifier trickery using a Vertex Weight Proximity and a Cast modifier.

Use the Vertex Weight Proximity to make a vertex group weight vary according to the distance to a random object, in this case a "cancer ball", then use said vertex group to drive the influence of a Cast modifier set to Sphere.

You can then dynamically adjust the size of the "cancer sphere" (and shape too) to influence the distortion of the blood vessels


In the BGE you can use your rig as it is but you have to animate using the Action Editor. To play these animations you need to use the action actuator.

If you want to use the rig in Unity you simply just need to export the rig from Blender as *.fbx. Select 'Armatures' in the export options. When importing to Unity you have to select 'Rig' in the import settings.

I don't know much about CryEngine but you might consider taking a look at the addon 'CryBlend'.

As far as I know you can import *.fbx files in Stingray too, so it's the same steps I explained above for Unity.


Is there a way to make a quick animation PREVIEW, to evaluate motion, etc.?

You can OpenGL render a movie with the 'Render OpenGL' movie button, found in the lower right header of the viewport.

It'll use your regular render settings for frame ranges/formats.  Personally, I like to render a sequence of pngs/jpgs into a temp directory, and then load the sequence in the Sequence editor.  But some people prefer a separate movie player application.


Global keyboard shortcut to execute text editor script

If you are only going to re-executing this script when 3D View is open you might add the shortcut to 3D View (global). I propose a different shortcut as alt+p is for showing the 'clear parent' menu, but it's up to you.

At the end of this list..

generic_executor.py

# something to test with..
import bpy
import random

x = random.randint(-6, 6)
y = random.randint(-6, 6)
z = random.randint(-6, 6)

bpy.ops.mesh.primitive_cube_add(radius=1, location=(x, y, z))

operator.py

import bpy

class GlobalScriptRunner(bpy.types.Operator):
    """Tooltip"""
    bl_idname = "view3d.global_script_runner"
    bl_label = "Global Script Runner"

    #@classmethod
    #def poll(cls, context):
    #    return context.active_object is not None

    def execute(self, context):
        print('i get called')
        textblock_name = 'generic_executor.py'
        textblock_as_string = bpy.data.texts[textblock_name].as_string()
        exec(textblock_as_string)
        return {'FINISHED'}

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

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

if __name__ == "__main__":
    register()

To wrap this into a reusable add-on requires more time than I have, but it's not the purpose of this answer. The benefit of having this as an addon would be that you could create a panel for 3dview in which you can type or select a textblock to be executed when the shortcut is triggered, rather than this hard coded suggestion, where it only executes a textblock named generic_executor.py

edit:

Here's something you could use as a starting point, it creates a panel in 3dview (right side panel) and allows you to pick a textblock. Whenever you trigger the operator view3d.global_script_runner , it would look at the name of the selected file and execute it.

https://gist.github.com/zeffii/2b488961226ee1ecefcf


Alternative Render engines can I use instead of Cycles for AMD Radeon GPUs?

AMD GPUs have a long history of issues with blender cycles, unfortunately the support for those cards is not 100% due to issues with the drivers.

You can try other rendering engines like the ones listed on the Resources for Blender Some of them have addons that integrate the render engine directly to blender. Some of them you can use for free, others are commercial products.

External Render engines:

Luxrender  is a physically based and unbiased rendering engine. Supports Blender integration.
Yafaray is a free open-source raytracing engine which supports both biased an unbiased rendering methods. Supports Blender integration.
TheBounty is a free montecarlo raytracing engine. (fork of Yafaray)
Mitsuba is a research-oriented rendering system in the style of PBRT.
Appleseed is a modern, open source, physically-based renderer designed for production rendering.
Jot is a program that lets designers, artists and animators directly annotate 3D computer graphics models (and animation) for stylized (NPR) rendering [in real time].

A blender exporter and more up to date info can be found here.
Nox is a free stand-alone, physically-accurate state-of-an-art renderer. Windows only(open-source since 2014 but seems original authors abandoned).
Aqsis is a cross-platform 3D rendering solution adhering to the RenderMan standard.
POV-ray is a high-quality, Free Software tool for creating stunning three-dimensional graphics. Supports Blender integration.
PRMan Another cross platform integration of Pixar's RendermanProServer 20.0+ (Free for non-commercial use).
V-Ray for Blender An add-on that packages a .blend file and converts it into a format that V-Ray standalone knows how to render.
B-Maxwell
The B-Maxwell add-on is a basic exporter from Blender to Maxwell Render (Windows and Linux). "B-Maxwell add-on offers seamless integration with Maxwell Render and Blender"
Octane-Render Commercial plugin for blender available. GPU accelerated Unbiased rendering engine.


Interpolate motion between motion track keyframes

Tracking is an art. Perfect automatic tracking is hardly ever possible and will require some manual supervision and/or interpretation.

For a few frames you can manually move the tracking points in the tracking graph (that green and red graph that gives you the speed at which the trackcers are moving in the horizontal (red) and vertical (green) axis)

Other things to try: animate the settings for weight and stab weight. Or bring down the coorelation when tracking fast moving objects and bringing it up again when the motion slows down. And of course you can always use the clean-up tools in the solve tab.


I get weird shapes when I extrude and scale a mesh

You are using Proportional Edit with the "random" falloff setting. To turn it off, click on the blue button in this menu and select "disable":

or press O while in Edit mode


Animation of proportional editing deformation (cylinder to figure eight)

You can do it the other way around:

Create your 8 shape:

Once you are good, in Object mode, create a basic shapekey and a second shapekey:

Keep the second shapekey selected and in Edit mode, select all and right click > LoopTools > Circle:

Back in Object mode, use the shapekey Value to morph from the circle to the 8 shape:


You should use the Stretch To constraint:

Build your cable, create an armature, with a small bottom bone, a central bone as long as the cable, and a small top bone that you unparent.

Select the armature, go in Edit mode, in the Properties panel > Object Data > Display, choose B-Bone. Select the central bone and in the Properties panel > Bone > Bendy Bones, segment your bone (for example 6).

Switch to Pose mode, keep the central bone selected, in the Properties panel > Bone Constraints give it a Stretch To constraint with the same armature as Target and the top bone as Bone.

Back in Properties panel > Bone, enable Use Custom Handle References and in the In and Out fields choose the bottom bone and the top bone so that the central bone will bend properly.

Parent the cable to the armature With Automatic Weight.

Move the top bone, the cable should follow.

What you could do to give it the right bend is to put an empty at the exact same position as the top bone, give the top bone a Child Of constraint, then move the empty to where it is supposed to be in the back of the head and parent it to a bone.


Why is there no subtracting effect for sculpting brush?

Found my problem, it looks like that the "F smooth" doesn't have an add/subtract option. I just want to smooth a little bit out and then work around that. Sorry for the waste of space. Perhaps the option "add/subtract" might be welcome for this option also.


Spherical gradient texture on plane not working

Connect Texture > Gradient Texture (spherical) to Diffuse color node, as a vector choose Object and add Color Ramp to play with colors and color blends.

Edit:

For transparency you can choose Color Ramp as factor for Mix Shader.

Edit 2:

I have created scene with the same unit settings as yours and here is what we have:

Plane, scaled to 2x2m.

And this very same setup but with applied scale (CTRL + A).

Edit 3:

I have checked it in Blender 2.77a and 2.78 RC1 and it looks all the same. So my guess (as Blender docs doesn't cover much about Texture Coordinates > Object) it's not a bug but this is how those calculations works. Other textures behave the same. You can 'fix' texture scaling in Texture tab without setting Mapping node and calculations there are correct - scale 100.

Edit 4:

Good catch with other dimensions. Now I'm totally stuned about it.
But here is a method that is working with every dimension scale (applied or not). Don't ask me why it is working, but it is working :)

You need to change Texture Coordinates to Generated then in Texture tab change Location to X > 5mm and Y > 5mm (this is part that I don't know why 5mm is ok for 2, 20 and 200m, this was my lucky guess) and Scale to 0.5.


How to use an if statement inside the draw function to change the UI at runtime?

Found the problem, 'icons' wasn't recognized because it was from a different class, I just had to reference it.

icons = scene.ignit_panel.icons

if icons == 'Brightness':
    row.prop(scene.ignit_panel, "brightness_icon")
elif icons == 'Backlit Keys':
    row.prop(scene.ignit_panel, "backlit_keys_icon")
elif icons == 'Volume':
    row.prop(scene.ignit_panel, "volume_icon")


There is an addon that allows you to do this, you can download it here:
Import GPX. You will also need to download the .gpx file from the website you linked in your question (select Download as > GPX Track).

Install the addon and activate it.

Go to File > Import > GPX (.gpx)

Select the .gpx file you downloaded, make sure that Use elevation for Z-coordinate option is checked, and clickImport GPX.

It may seem that nothing was added to the scene but you'll notice a new object in the Outliner (with the same name as your .gpx file). You can't see it in the scene because the track is very big (it's 2 km wide). Unless you want to keep it the original size, select the object, press N to open Properties panel, and change scale to something like 0.005. You should be able to see the whole track now. Apply the scale by pressing Ctrl + A > Scale.

Press 3 to view the track from the right side (ortho) and Tab to Edit Mode. Select all vertices (A) and extrude them (E) down on Z axis (Z).

Press S > Z > 0 to align vertices on Z axis.

Go back to Object Mode (Tab), press N to open Tool shelf and enable smooth shading on the object.

Enable Auto smooth option in the Object Data panel, and set the Angle to 80°.

Add Solidify modifier and set preferred Thickness (3 cm look nice).

Add a ground plane, add a white diffuse material to both the track and the ground plane, add lights to the scene (only sun lamp in my scene) - and render.


Select all vertices, hit X button and select Limited Dissolve from the menu.

Then hit F6 button and adjust Maximum Angle to get desired result.

Then to triangulate the mesh hit Ctrl+T shortcut.


What are the colored/highlighted edges in edit mode?

Those edges have been marked.
There are actually five types of markings you can apply to edges:

Red - UV Seam
Blue - Bevel Weight
Purple - Edge Crease
Cyan - Sharp Edge
Green - Freestyle Edge

You can mark edges yourself from Edit Mode using the Edge menu (Ctrl+E).

Colors in Blender 2.79:

Red - UV seam
Orange - Bevel weight
Pink - Edge crease
Blue - Sharp edge
Green - Freestyle edge


Some other suggestions for VSE performance enhancement:

Convert your video into image sequence (e.g. PNG), then reload them to VSE to replace the original video strip, which can solve many unknown problems caused by codecs.
Use Proxy to speed up even further.
If you are using scene strips, it is highly recommended to toggle Open GL Preview (from the properties of the preview) for faster real-time preview.
You can also consider setting priority for Blender process (e.g. in the task manager / resources monitor utility of your OS), which is generally not recommended unless necessary.


How to batch rename embedded (linked) textures in a scene?

This question was answered at blenderartists. See the solution with a phyton script here:

https://blenderartists.org/forum/showthread.php?441069-How-to-batch-rename-embedded-(linked)-textures-in-a-scene

Thanks to the users Photox and MartinZ for help!


Rigid body hair mesh clipping and collision issues

From the looks of it, adding more bones that better aligned with the finer details of each mesh seemed to solve the issue of why some collisions were working better than others. I noticed the bones were more or less adhering to the rigid body parameters, but visually it wasn't apparent because the braids attached to them weren't perfectly aligned.


Using 'Bake Sound to F-Curve' to Drive Animation -- Invalid Python Expression

Drive the pose bone custom property.
Please note, didn't see the image correctly, it appears you have baked sound onto armature bone (the structure). In most cases recommend using the pose bones, which belong to the rig object, not the rig. If you really want to use the armature bones, go to second part of answer
Check out examples here https://docs.blender.org/manual/en/latest/animation/drivers/workflow_examples.html#workflow-examples
Without checking the tute, you are going down the garden path.  Am assuming this custom property is on a pose bone of the object (pose mode), not a bone of the objects armature data (edit mode).
In example below have a property "prop" on a pose bone named "Bone".  This was set in pose mode, with bone selected in the Custom Properties Panel with Bone tab selected.  Consider this the prop I have baked sound on. Change names to suit your case

The object of interest is
bpy.data.objects["Armature"]

not
bpy.data.armatures["Armature"]

which btw is
bpy.data.objects["Armature"].data

In driver variables we do not use this as the data path instead choose the ID object, be it an Object or an Armature, a Mesh etc etc.. It is an Object type in this case.

For a single property type driver variable the path is relative to object selected as the driver variable target.  Hence in case above this is
bpy.data.objects["Armature"]

and the path to the custom property from here is
pose.bones["Bone"]["prop"]

This can be copied from the UI by right clicking over property and choosing "Copy Data Path" and pasting into path field of driver.  Result of paste.
pose.bones["Bone"]["prop"]

Using the Armature bone
On closer inspection it appears you have driven the armature bone. Would suggest changing this to the pose bone for most use cases.
If it is the case, then select the armature from Armatures when creating driver variable and use

bones["Bone"]["prop"]

as the path. As can be copied from

in object mode.


Your active camera has Depth of Field enabled and the focus is controlled by the object camera DOF. But for some reason, your camera DOF is in the nirvana. If you select it and try to grab it with G the location is nan(ind)?! Similar to this question nanind-m-location-for-camera. (Honestly, I don't know how to fix this.)
I just would delete the bad object, create a new Empty and specify it as DOF object. Move the Empty (Sphere in the screenshot) to your model. This is where the camera's focus is. The background will be blurry.


Will additional lights make an object appear strangely colored?

Yes, I think the additional lights are making the objects darker.  I moved everything to a different area, not moving the lights, and the color is coming back.  To me this makes no sense.  More lights should wash it out shouldn't it?


Is there any way to select all the "edge faces" of this cut-out sphere?

I suggest using select similar > perimeter. Press  Shift  + G to bring up the selection menu after selecting a face loop similar to the desired loop with  Alt  +  RMB , then adjust the threshold until you have the desired results. Double check your model to make sure there isn't a missed face anywhere, but this should get all of them. In my example, the threshold was 0.030


Cycles Render Option Not Showing Up In Blender 2.77

You have to enable it in user preferences and addons.


All of the options are there, just select Add curves Spirals (it doesn't matter which one, you can change them later.

The options are on the toolshelf.

It the toolshelf is not open you can press T to access it. Or pRess F6 to get a floating window with the same options.


Use the Decimate modifier in the Collapse mode, then adjust the Ratio property as desired.

Bad topology and occasional glitches are to be expected, you may have to do additional cleanup by hand. You can also try the Remesh modifier if you wish to retopologise.


I'm not sure what you want, but if I understand correctly, you can make the background image color information remain in the image while still making it completely transparent.

This can be done with the Set alpha node, with an Alpha of 0:

However, in the video you linked to the scene is rendered without any information about the background image at all.

Here is a setup that will do this:


Move selected vertices to grid with by a specific distance

You can change the grid unit settings and snap to the grid:

Though, 0.0000002 could be a floating point accuracy issue.


Applied Subdivision Surface Modifier To a Mirror Modified Model The Model Enveloped in on Itself

Your model seems to have faces at the border between the two halves, so to Blender it looks like they are separate.

Remove these faces
make sure that the mirror modifier is above the subsurf modifier
make sure that Merge is enabled for the Mirror modifier


Instead of an emission shader just add a "Holdout" shader and anything behind it will be left out.


What causes AttributeError: 'Material' object has no attribute 'texture_slots'?

Material.texture_slots is only available for blender internal render.

How to add a Texture to a Material using Python?


Use the Boolean Modifier. Or if you want to have a better workflow use the BoolTool addon. Tutorials on how to use them are enough out there and its quite simple but I will explain it nevertheless.

Add the Boolean Modifier to the first object you want to merge.
Click that little eyedropper in the object box of that modifier.
hover over the object to merge with and press LMB
Apply the modifier and delete the mesh that you selected with the eyedropper

All of that can be done with the BoolTool addon with one click on the Direct Union button


Enable Clipping on the mirror modifier:

To get it to scale completely as it would have before deleting half and mirroring, you must use the 3D cursor as the pivot (.). The 3D cursor also has to be in the center of the cylinder. The easiest way to get it there is selecting middle vertices and pressing ShiftS>Cursor to selection.


Loop multiple objects along the same path

Using Drivers and Follow Path constraint.

Drive the offset of the constraint from 0 to 1 using Fixed Position.

Hard coded 250 as the path length in frames. The driver method has two parameters, the current frame (scene.frame_current is known to the driver namespace as frame) and the offset at frame 0.

import bpy

path_length = 250 # path length in frames

def offset(frame, start=0):
    # start position at frame 1
    f = round(frame + start * path_length)
    return (f % path_length) / path_length

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

Sample file and image with Cube (offset 0), Cube.001 (0.2) and Cube.002 (0.4).


The two standards for DVDs are NSTC or PAL. Both are a rather low quality format by today's HD standards. You said that you are coming from old media, so going to DVD there will be no loss in quality.

Blender makes it quite easy with presets. Here I'm assuming NSTC.
Everything you need to set is in the Render tab of the properties window.
There is a preset for the dimensions: TV NTSC. The preset for the output is split among two headings Output and Encoding. Choose MPEG for the file type, and make sure it is set to RGB. Then the default DVD preset for the encoding works well.


Why blender keeps crashing while rendering this simple animation?

I found the solution, that is to render with console only and limit the number of threads to 2 instead of auto with the command:

blender -b "file name.blend" -a -t 2