UV unwrapping turns the uvmap model inside out

You have the option Fill Holes turned on in the Unwrap settings which gives the undesired result in this case.

Turning it off will unwrap your model correctly.


Rigid body simulation always has a visible collision space

This seems to be caused by the Subsurf modifier on the Suzanne.

Frame 124 with the Subsurf modifier:

Frame 124 with the Subsurf applied:

In addition the Backdrop had a collision margin of 4cm, in the images above it is set to 0.

Comparison of frame 124 with the collision margin of the BackDrop set to 4cm and 0m:

I also set the Collision shape of the Suzanne to Convex Hull and disabled Collision margin.


Is it possible to render as it is displayed in Material Preview?

You can turn off your overlays, then in the 3D viewport go to View -> Viewport Render Image. You can render even viewport animation from this menu.


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


If you think in terms of layers, this layer will be your background:

All other images will be composited on top so it doesn't need any transparency or alpha channel. Do not mask it and let the background be flat and uncut.

Over your background you are using a foreground layer. Use Alpha Over instead of Add.


Cloth physics do not work with collision

Your version will be very heavy for calculation because for such a stringy collision you will have to extremely increase "Quality Step" value in Cloth Sim. I would try simple cloth mesh baked and for your hires basket net use Surface Deform modifier with Target baked simple cloth.

Basket

add Cylinder (12 sides), add few horizontal LoopCuts Ctrl+R
Ctrl+E > Un-SubDiv 1 switch squares to rhombus net ... shape it as you like
select top vertices and Assign them to Vertex Group under Data Properties
add SubSurf modifier > Simple

Simulation

add Physics Properties > Cloth > Shape > Pin Group
Bake

From here you can use your hires basket if matches lowres model shape. For example here I just

Duplicate lowres basket
Delete Cloth Sim
Delete X Faces Only
add Skin modifier
add Surface Deform modifier > Target lowres model with cloth simulation > Bind

Like now the lowres drives highres model animation and you can anytime go to lowres and run sim independently on hires model.

Notes:

More details for diamond net see this A
Cloth Properties - preset Denim, substeps 32, Vertex Mass 0,1 kg, Stiffness 30, Self-Collsion ON
Skin modifier - select all vertices and from 3Dview properties panel (N) decrease Mean Radius to 0.05


How to use image as plane with matcap turned on

The image that you want to keep is created by a material. The purpose of a matcap is to override all of the materials with the matcap material. This includes the material on your plane. As far as I know, there is no way to exclude an object from having the matcap material.

I would suggest using a custom matcap on your other objects instead, which is essentially just a material that looks like the matcap material. CG Masters did a fantastic tutorial on how to set that up here that also includes links to images that allow you to recreate the same matcap that you are using already.

Your other option is to enable viewport ambient occlusion. This won't make the objects look like they do with a matcap, but may help give you a bit more visual clarity while modelling by making corners and creases a bit darker. The option for that can be found just under where you enable matcaps. I would definitely suggest the first way though with the manual matcap material, as it's going to do exactly what you want.


Change red spot value to 0 that may help you.


Joining 2D tracking markers with an offset

To track areas that are blocked by obstacles or temporary going off-screen. Move the tracking marker before the area is hidden by pressing GG and dragging the marker to another tracking point, or offsetting the marker in Track properties panel in Marker section by changing X and Y offset position. You can then continue tracking the scene under the offset tracking area until the original tracking area is visible again, then move the marker back using the same procedure.


How do I connect these two vertices by extending them along its edge util they reach each other?

Edit: grilled by Mr Zak  ;)
You can extend the 2 edges so that they overlap: slide GG and C to extend. Then enable the TinyCAD addon, select all and right click > TinyCAD > XALL Intersect, it will create a vertex at the intersection. Remove the rest.

Or, as mentionned by the Great Robin Betts, don't slide, just select all and choose VTX Auto, it will intersect automatically, you'll just have to dissolve the remaining vertices with CtrlX:


How to make camera continuously move along the circle path?

Don't attach camera to curve. Unparent  it and use the follow path constraint on the camera. Set the camera coordinates to 0,0,0 (this should put the camera on the path, if not you can do it manually. Check follow curve, then set the camera rotation. This should work.

here is what mine looks like:


Is it possible to blend from 1 to zero in Vertext Paint mode?

Similar to the answer to Smoothing vertex_colors values this can be achieved by assigning the 'fixed color' vertices to a Vertex Group and using a script to 'smear' the color from those vertices over the rest of the mesh.

You could use the script in the linked answer but for ease of use I have packaged it into an add-on which is avialable for download from Vertex Color Blend Add-on. To install the add-on, simply Download the file and use the User Preferences Add-ons 'Install from file' option and click the checkbox to enable it.

Once enabled you should have a new option in the Paint menu for Blend Vertex Colors

Go into Edit mode on  your mesh and add a new Vertex Group - name it something like 'FIXEDCOLORS' and assign the vertices you want to have fixed colors to it. Ensure no other vertices are assigned to that group.

Use Vertex Paint to paint those selected vertices the desired colors - it doesn't matter if other vertices are also painted as those will be ignored by the 'blend' process.

Select the Paint/Blend Vertex Colors option and you should get a popup as follows :

Set the Number of steps and initial red, green, blue settings as desired and the Vertex Group to the 'FIXEDCOLORS' vertex group created earlier and click OK to apply.

After a short delay your vertex colors should be updated to blend the 'fixed' colors over the mesh.


How could I avoid UV maps when combining procedural Textures?

You have to keep them. UV Mapping is the default texture coordinate for image textures in Cycles, but the generated textures use generated coordinates by default:

  Texture coordinate to sample texture at; defaults to Generated texture
  coordinates if the socket is left unconnected. (http://wiki.blender.org/index.php/Doc:2.6/Manual/Render/Cycles/Nodes/Textures, Wave Texture)

You could simplify the setup if you pressed CtrlG to make the two nodes a group (a group looks like a single node). You can edit a group by pressing Tab.


Why are some textures disappearing in the game engine?

So instead of using multiple UV layers for scaling the textures i used the 'size' option in the 'mapping' panel. It runs faster...


How to round edges of particular faces where I have assigned emission material?

Better if you use a mix shader with a mask, instead of this method. Of course you can paint the emission pattern if you have a UV map.


Assigning my rigged model to a Mixamo skelton

Create a copy of your rigged character, go to the first frame (or a rest pose frame, if it does exist), use your rig to copy the pose of the Mixamo rig as close as possible, then go to the modifiers and apply the armature modifier.
Not necessary, but if you want to stay clean at this point you can delete the rig and all vertex groups.
Select the character, shift select the Mixamo rig and press Ctrl P (Automatic weights).
Then you can turn on and off the visibility of the two versions of your character.


I was using the GPU as render device.

I simply needed to change the render device to CPU, after which, it rendered perfectly.


Select objects, press Alt+P. Select Clear Parents and Keep Transform, if you want to keep their current positions.


It's a quadrilateral, you need to define 4 verts.

Test method, x and y are pixel coordinates of bottom left corner of rectangle, h and w the height and width (in pixels) respectively.

def draw_box(self, x, y, w, h, color=(0.0, 0.0, 0.0, 1.0)):
    #bgl.glDepthRange (0.1, 1.0)
    bgl.glColor4f(*color)
    bgl.glBegin(bgl.GL_QUADS)

    bgl.glVertex2f(x + w, y + h)
    bgl.glVertex2f(x, y + h)
    bgl.glVertex2f(x, y)
    bgl.glVertex2f(x + w, y)
    bgl.glEnd()

Run-able Example


Exact meaning of "film exposure" in blender cycles

Based on the code on gitHub (kernel_film.h), it looks like the exposure is indeed a simple multiplication, applied on the linear space before gamma correction:

ccl_device float4 film_map(KernelGlobals *kg, float4 irradiance, float scale)
{
    float exposure = kernel_data.film.exposure;
    float4 result = irradiance*scale;

    /* conversion to srgb */
    result.x = color_scene_linear_to_srgb(result.x*exposure);
    result.y = color_scene_linear_to_srgb(result.y*exposure);
    result.z = color_scene_linear_to_srgb(result.z*exposure);

    /* clamp since alpha might be > 1.0 due to russian roulette */
    result.w = clamp(result.w, 0.0f, 1.0f);

    return result;
}


How to convert an object transformed by a Hook Modifier to an object with Loc,Rot,Scal Transformations?

You can parent both your object and the hooks to an empty, that would take care of the origin.
You can also use the empty if you want to animate all the cubes relative to each other.

However:
I would strongly suggest you just use an armature with 3 bones and put one vertex to weight 1, and the other 2 to 0 for each according bone. Hooks are dangerous, they have no rest position, and an armature keeps everything neat and tidy.

You'll probably need to check a more detailed tutorial on this, but here is the breakdown:
Add -> Armature
In edit mode on your triangle, select one of the vertices -> cursor to selected.
In edit mode on armature press SHIFT A, it will create a bone at the cursor location. Call the bone 'A', repeat for 2 other verts.
Object mode, select object, then armature -> CTRL P -> with empty groups.
Edit mode on your plane select a vertex, select the group of the bone it's supposed to be dragged by make sure weight is at 1.0 and press assign.
Take One of your cubes, SHIFT-select the armature, go into pose mode, select the corresponding bone, CTRL P -> active bone, repeat.
If this was too abstract there's tons of tutorials on that online.


Is a photo editor or vector graphics software essential for 3D creation and Modeling

There is no such a rule.  In fact there are no rules at all here. It depends on what you want to do. No software is essential in digital art. You can use whatever you want or like and whatever gives you the desired results. With that said it is a fact that photo or image editing software is extremely useful when working with 3d.

Having worked with Photoshop almost every single day of my life for the last 15 years or so I can say... that it does not necessarily need to be Photoshop :D . It's a good and popular choice, but you can definitely find good or even better alternatives. You can choose Krita, Affinity Photo, Gimp or even do some painting straight in Blender, but Photoshop will do as well. Or don't choose at all, use all of them that you can get your hands on. As for you not wishing to spend time on it... Well I would recommend not to think too much about it. You will not waste that time and you should be prepared to spend loads and loads of time if you are learning CG anyway. The main concepts are pretty similar in most image editing software packages and will be useful whatever you choose. In 3d graphics context, image editors are relatively simple, so it's definitely not a bad idea to just choose one and learn it. Don't make a big deal out of it.


How to model a frustum with specific radii?

Press ShiftA and choose Add Cone:

Press T to show the Tool tab.

The Radius 2 will allow you to make the top flat.

Radius 1 is the base radius, and Depth will determine it's height.

Another option to access the tool's proerties is by pressing F6


Depth of Field with Grease Pencil Objects not working

Unfortunately Grease Pencil doesn't have true camera DOF enabled yet, but there are several workarounds available:

1) Add the "blur" effect under the "visual effects properties" tab and check "Use Depth of Field". The grease pencil object will then blur with camera movement(but it only blurs the GP object as a whole instead of parts of the GP object as in true DOF)

2) Convert the grease pencil object to geometry, which will then react properly to camera DOF: https://www.youtube.com/watch?v=Fl8PXZWnxr4

3) All grease pencil objects come with a depth map.  Use the "Defocus" Node and "lens distortion" node in the compositor.  You can download an example file of the node setup here: https://www.local-guru.net/blog/2019/7/13/grease-pencil-experiment-4---depth-of-field

It's likely that true camera DOF will be enabled in a future version of Blender, but for now these workarounds may provide the result you are looking for.

Hope that helps!


The value of TextBox cannot be obtained and an error occurs

You are trying to access a member named query of your operator on lines 53 et 63, but it doesn't exist. Instead you want to access the property group you created in your register method : context.scene.QueryProps_query.query.
Side note : Don't use bpy.context in an operator, because it is not always the right context. (L.28) Use the provided context parameter instead.
import bpy

bl_info = {
    "name": "test addon",
    "author": "taichi suzuki",
    "version": (1, 0),
    "blender": (2, 80, 0),
    "location": "3DView",
    "description": "test addon",
    "warning": "",
    "support": "COMMUNITY",
    "wiki_url": "",
    "tracker_url": "",
    "category": "test"
}

class QueryProps_query(bpy.types.PropertyGroup):
    query: bpy.props.StringProperty(default="aaa")

class TestAddon_PT_Panel(bpy.types.Panel):
    blidname = "TestAddon_PT_Panel"
    bl_label = "TestAddon Panel"
    bl_category = "TestAddon"
    bl_space_type = "VIEW_3D"
    bl_region_type = "UI"

    def draw(self, context):
        props_query = context.scene.QueryProps_query
        layout = self.layout

        row = layout.row()
        row.label(text="test textbox")
        row.prop(props_query, "query", text="")

        vis_box = layout.box()

        vis_box.operator(TestAddon_OT_Operator.bl_idname,text ='modal start')

class TestAddon_OT_Operator(bpy.types.Operator):
    bl_idname = "wm.modal_testaddon_operator"
    bl_label = "Modal testaddon Operator"
    _timer = None

    def __init__(self):
        self.test = None

    def modal(self, context, event):
        if event.type in {'ESC'}:
            self.cancel(context)
            return{'CANCELLED'}

        if event.type=='TIMER':
            print(context.scene.QueryProps_query.query)

        return{'PASS_THROUGH'}

    def execute(self, context):
        wm = context.window_manager

        if TestAddon_OT_Operator._timer is None:
            TestAddon_OT_Operator._timer = wm.event_timer_add(1.00/60.00, window=context.window)
            wm.modal_handler_add(self)
            print(context.scene.QueryProps_query.query)

        return {'RUNNING_MODAL'}

    def cancel(self, context):
        wm = context.window_manager
        wm.event_timer_remove(self._timer)
        TestAddon_OT_Operator._timer = None

classes = (QueryProps_query,TestAddon_PT_Panel,TestAddon_OT_Operator)

def register():
    from bpy.utils import register_class
    for cls in classes:
        register_class(cls)

    bpy.types.Scene.QueryProps_query = bpy.props.PointerProperty(type=QueryProps_query)

def unregister():
    from bpy.utils import unregister_class
    for cls in classes:
        unregister_class(cls)

    del(bpy.types.Scene.QueryProps_query)

if __name__ == "__main__":
    register()


Import PLY doesn't display vertex colors

The .PLY importer makes a Vertex Color Layer, if you switch to it you will see the colours.

And as a cycles material:


Snap object with assigned rotation to surface

The problem here is that you've applied the rotation transformations to your button, or rotated the button around in edit mode, causing the object's local axes to no longer line up with what you consider to be upright for your object.
To show you what I mean, here are the local axes for your button object:

And here are the normal axes for the face you're trying to snap the button on:

What Blender is doing when you're snapping the object is aligning the local XYZ-axes of the button to that of the cube. However, your desired orientation doesn't match that of the object's orientation, so when the local axes are aligned to the face of the cube, the button is at an angle to the surface (in other words, the XYZ axes in the first picture are rotated to match that in the second picture).

There are different methods you can try to use to manually rotate the object back into position, but in this case, it would be easiest to just recreate your button.

If you were unable to recreate your button, you can try to rotate the origin of the object so that it matches what you consider an "upright" position for it. To do this, go to the Active tool and Workspace settings tab and select Options > Transform > Affect Only > Origins. I would not recommend this here, as this will cause unwanted movement of parented objects.

The second way to realign your button is to enter edit mode and rotate the entire object in there since transformations done in edit mode do not affect the object's origin and hence, the object's local axes.

PS: I would consider making the black part of the button the parent, not the white part. If you try to animate the white part by pushing it down, the black part will move with it in the way you have it configured right now.


everyone!

I'm the same person as the asker - had to make a new account because Stack Exchange said I hadn't used their email to confirm my email address (because I never got one).

I'm not sure why it was screwed up to begin with, but Blender works on my system now. I updated the drivers of my Display Adapters in the Device Manager.


How to recenter origins of objects on one axis

Bounding box center

IIRC center to geometry is also the same as bounding box center.

Test script, finds the bounding box center cog and only translates the z component.

import bpy
from mathutils import Matrix, Vector
context = bpy.context
ob = context.object
me = ob.data

bbox = [Vector(b) for b in ob.bound_box]
cog = sum(bbox, Vector()) / 8

me.transform(Matrix.Translation((0, 0, -cog.z)))

Changing last line to

me.transform(Matrix.Translation(-cog))

will move origin to center of bounding box.


Objects appear normal in material preview but in rendered mode with cycles they're encased in weird material blobs

The 'blob' happens when you set high Midlevel in the Displacement node.
Yours is set to 4,2 (default is 0,5)

The 'blob' cannot be selected, because it's just displaced polygons
It only happens in Cycles preview, because Eevee preview doesn't support displacement
Noise texture only suplies values 0-1, so high midlevel may look weird

  Displacement Midlevel
  Neutral displacement value that causes no displacement. With the default 0.5, any lower values will cause the surfaces to be
  pushed inwards, and any higher values will push it outwards.

  Blender Manual


Why does my texture bake come out as completely black? (The age-old question.)

Ok, it turns out that a node group that I appended from Poliigon ("Poliigon Colour Variation") somehow breaks the baking process. I'm not really sure how, since I thought the group was meant to be a black box that takes colour in and pipes colour back out, but it might be useful for others to know. Here's a screenshot of the meddling node group:


Blender exporting sharp edges to mesh file

One solution is to:

Go to properties panel
Add edge split modifier and apply it.
Export your model to any format that behaves well with the target software.

Use edge split before exporting your file.


How to copy a specific area in a 3d map?

Your request it's not so clear, but I'll try anyway.

press Tab to get into Edit Mode
press Num 7, Num 5 to get in Top ortographic view
press the X-Ray button (in the picture)
press B and drag with the mouse to select the areas you want to delete (or use the circle selection tool with C)
press Del (the "delete" button, which has different names in different countries) and choose Vertices

keep doing that until you get the area you want, and try to cut along streets or parks, so that you don't cut buildings in half
press Tab to get back into Object Mode
select your model and export it from the File > Export menu

If you want to make a game or something else and you need the map to be closed (so a smaller map instead of a portion of a bigger one), you need to create some natural barriers, like walls, mountains or sea, on the edges of the map.

While doing that you need to re-route the severed streets (just copy-paste the existing ones)


The blue Add node is a math node. Search Math, click on the result, and this will pop up.


Odd artifact in mesh only when rendering in cycles, starts at third frame

One additional cut it solved.

But ... I cant find what it cause. I checked face orientation, shading type collision, make face planar, deleted all 88 thousand duplications (merge by distance), deleted all from scene (if it is not in hidden, isolated problematic face, unpluged material, tried Normals ... but nothing affect the issue. Only triangulation. Limited disolve to make n-gon back, brought issue back. Now Im interersted too :)

Definetely overlapping faces like n-gon tries to connect in two sharp angle?


Action (animation) actuators need to be part of the object, which you want to animate.

In the .blend, the animations are applied to the "ground" plane instead.

To make objects interact with each other in the logic editor, select them at the same time using Shift + Leftclick in the Outliner:

You will see the objects in the logic editor:

Then edit the logic so that one object's controller controls other objects' actuators:

You can see the full process in this video.
Unfortunately two of the arrows don't animate correctly and I'm not sure why that is. Perhaps their transformations need to be applied?


I think doing what's described here How do rigs relate to weights? will help.

If you parent the mesh to the bones 'with automatic weights', it should try to correctly weight paint the mesh to the bones fairly well. And if still looks 'weird' on some parts such as 'too sharp' bending, or 'too soft' (like what you're experiencing), then you need to adjust the weight painting a bit.

hope it helps!


What are these strange shades in the BGE?

From the screenshots, this looks like a problem with the normals of your mesh.

In editmode, try CTRL + N to make normals consistent to see if that solves your problem.


How do I rig Walschaerts valve gear in Blender?

I think the problem is that you have the valve stem and crosshead rigged to move together.  In an actual valve, the motion is more complex

I'm not good at drivers, but what I think you need to do is match the actual cycle more closely.

Using the animation from wiki starting with the valve stem all the way to the right end of its cylinder, the piston end of the cross head in the middle of its cylinder

Steam enters, pushing the piston to the left end of its cylinder
As the piston approaches the end of the cylinder the various mechanical linkages pull the valve stem to the left.
Once the valve stem is all the way to the right, the direction of steam reverses. This reverses the direction of the piston.
The piston moves all the way to the right
Mechanical linkages pull the valve stem to the left

end of cycle.

A driver that causes the cylinder head to move as if it were driven by steam and a set of bones that match the actual mechanical linkages, down to parenting, should cause everything to behave properly.


Upgrading to 2.81 - How To Keep Settings and Addons

When you install 2.81, there is an option to import settings from 2.80. However it is unknown what custom tweaks you did to 2.80, so hard to answer if all will be that easy to transfer.

Under <user>/AppData/Roaming/Blender Foundation/Blender you'll find config files for all the version.

You won't loose addons, you will just have to copy them from 2.80 addon folder into 2.81 addon folder. Most addons will be fine, but some addons might not work under 2.81 and you'll have to wait until the addon developer updates the addon for 2.81. There are some small python API changes between 2.80 and 2.81.


How to make the light emission invisible?

You can use a Light path node to mix shaders based on the properties of the incoming ray.

For example, this node setup mixes Base material and Line material based on Line texture, then mixes that with Base material based on the kind of incoming ray; rays coming directly from the camera will see the mix of Base and Line, but other rays will "see" only Base.

So shadows and indirect lighting etc. will be cast as if Base shader was connected straight to the material output.


This is happening as a result of non-uniform scale. What this means is that you have scaled your object in object mode, and not "told" blender to adjust proportions accordingly. To fix this problem, enter Object Mode, select your object, press Ctrl+A and select "scale".


How to open system console to get output from Blender on Mac OS 10?

Right click on the Blender icon in the Applications folder and select "Show Package contents". Make an alias of Contents/MacOS/Blender by right clicking and selecting "Make Alias". Rename it and move it somewhere you like.

This opens the console in the background, next to the Blender application.

source:
https://www.lynda.com/Blender-tutorials/Set-up-Blender-console-window/486043/533594-4.html


There are a number of online resources available that keep track of a number of Blender Addons, though I am not aware of any one centralized site that covers all of them.

Your first go-to resource is going to be the Blender Wiki's Scripts page, which keeps up-to-date information on all of the addons that come packaged with the Blender installation, as well as several others.
Another valuable resource is the unofficial Blender Addon List, a listing of many Blender addons maintained by Daniel Banasik.
Yet another resource is Graphicall.org. I am aware of a number of different user compilations of various scripts, but perhaps the largest of these is on this page.

The short answer to your question is that these resources are scattered everywhere, and while there are some that cover a large number of Blender addons, there isn't yet one location that keeps track of all of them.

Furthermore, the process of pulling these resources into one centralized location would be a logistical nightmare, with whole hosts of differences between how different scripts handle updates, as well as certain scripts being made obsolete by updates to new versions of Blender. I won't say it can't be done, but it would certainly be difficult to keep track of those things any better than the resources already out there.

Edit: zeffii also pointed out that you can get a zip with the most recent version of Blender and all user-contributed addons at builder.blender.org

Update: Added the Blender Addon List and removed a link to an inactive resource.


You need to select OpenCL instead of CUDA for rendering with AMD cards.


My objects are semi-transparent, and not one behind the other in the compositor

What you describe as "transparent" is the result of adding the RGB pixel information of an image to that of the others.

When using add the pixel values of each of the images are summed and will make final image brighter.

If you want them to create the illusion of having one image in front of another, you need to use an alpha channel and have that control how images are combined.

A proposed workflow:

Render each layer with a transparent background, to do that enable the Film Transparent Option for the scene.

Use the alpha channel to determine how they combine over each other. The Alpha Over node is one of the options that will allow you to do that.

The node sockets to which the images are connected determines the result:

The background image should be connected to the top socket

The foreground image or scene to the bottom socket.

The foreground's alpha channel is used to control the overlay the foreground's RGB color information on to the background.

click on the image to enlarge

The most basic example would be like this: where the UFO is the foreground element and is combined over the landscape using the UFO image's Alpha Channel:

click on the image to enlarge

If you have more than two layers, you combine one on top of another, and then combine the result with yet another layer and so on like this:

click on the image to enlarge

Note that if the background image has an alpha channel, both alphas are combined.

click on the image to enlarge

An alternative to the Alpha Over node would be using a RGB mix node and using the Alpha channel of the foreground layer control the mix with the background:

click on the image to enlarge

Another example:

A simple scene: Three circles, the red is on top of the others and the green on top of the blue one. They've been separated in different layers.

Using the add operation will result on the sum of the values for each pixel for each of the RGB channels of the image, a simple A+B operation.

See what happens where the circles overlap, where each of the RGB values of a layer are added on to those of the other layers:

The Alpha over operation is a bit more complex: A+B(1-alpha)


Mesh disappears when removing parent armature relation

Did you notice the mesh dimensions in the 3D view sidebar? It goes from meters and centimeters to centimeters and millimeters. It's not disappearing, but shrinking to such tiny dimensions you can't see it with the armature visible.

Instead of removing the parent at the Object panel, try the following: With the mesh selected and cursor on the 3D view, press Space, then Clear Parent > Clear and Keep Transformation.

That should preserve the transformations affecting the mesh while it was parented to the armature, what won't happen if you simply remove the parent from the panel.


So I am having this bug where my model in a game is transparent when you look at it from a certain angle

It looks like flipped normals. Try to select faces of that geometry and in the left toolbar select Shading / UV tab -> Normals: Recalculate. Or select only those "transparent" faces and hit Flip Direction.


Paper model effect from Royal Institution titles

My thoughts:

Every surface must contain a paper texture, even of only slightly visible.
Make the paper look a little used (dirt, coffee stains, bit crumbled up, more hints)
Light the place as if it was miniature (soft shadows, big lights)
Focus as if it was macro (blurry background)
When drawing on the paper, use near-real pencil.
Cycles - definitely use cycles for this.
Freestyle is not a must, but can help.
Extra help is small dust particles on the ground and flying around.

I think the strong point of that video is realistic lighting: very varied sources and realistic bouncing, warm temperature. Also it doesn't stay on too long, I bet you can get a better result if you try!


It won't let me parent the Rig to the Mesh?

If you're trying to parent the rig to the model, its the other way round. You first have to select the rig you want to parent, and then the mesh you want the rig to be parented to. then ctrl+P and you should be done.
-Yoshi


Some Materials Not Rendering, But They Are Applied

Some of your objects are duplicated.  In your .blend file, I selected one of the window shutters having problems showing materials.  I moved it away, and found there was still a shutter there.  One had material, and the other didn't.  Coinciding surfaces are unpredictable - you'll see parts of one and parts of the other mixed up, and exactly what you see  may change with camera position and viewpoint.

Solution is to find and delete those duplicate objects.


Mesh is almost entirely black in rendered mode

Your model is quite a mess.

Your sunlight doesn't seems to be emitting any light - Create a native Cycles Sun or give the current one a proper shader node tree.

Your model is full of custom normals which are known to cause shading trouble - Clear your custom normals

Some textures seem to not be picking up proper UV channel - Add an explicit Texture Coordinate node with UV coordinates to your textures.

Most of your geometry seems to have Inverted Normals - Recalculate normals and make sure they are pointing outwards


Why are solid objects with refraction node so dark?

It's difficult to be sure without seeing your nodes for the material, but this is most likely due to the way the inner surface is reacting with the roughness of the refraction to refract beyond 90 degrees due to a combination of the angle of incidence of the incoming ray and the roughness. For example :

Depending on your requirement (whether you want the material to actually behave as 'refractive) you could either address this by using the Backfacing geometry input to mix between Refraction and Transparent (effectively hiding the backfaces) :

Or also use the Incoming for for the Normal so that rays are always refracted just for the roughness, not the actual surface angle :


I'm trying to create this model for 3d printing. Blender says I have zero faces even though they have area. How do I fix this?

I believe that is telling you there are zero area faces present, and that tool will  highlight them if you click on the actual button that is reporting them . You can probably simply delete the faces it has highlighted and all will be well.
Maybe a better approach would be to select all of the faces in the object (in edit mode) and then go to Mesh -> Clean Up -> Degenerate Dissolve, which will dissolve all zero area faces and zero length edges ....


Cycles and Unity render method are totally different, you can't expect a Cycles material to look the same in Unity. But you can try a few things.

Baking

Baking is a tool that allows to "convert" your material into a texture.  Doc

The advantage is that the (costly) render is done only once, and the realtime engine only have to display a texture (cheap).

The disadvantage is that most material effects can't really be baked, because they are view dependent (ie. reflections).

Lighting can be baked if you don't need dynamic lighting (ie a light that move or change intensity). You can do it with Cycles, but it's certainly easier to do it in Unity Doc

PBR workflow

Physically Based Rendering (PBR) is a workflow that is supported by either Cycles (with the Principled shader) and Unity (with the Standard shader), and many modern game engine. It won't make the Unity shader look better (it's already the default shader), but at least it allow to have a relatively similar result while you are working on your object in Blender.

Game engine side

I won't be really specific cause I'm not an expert (and that's not the place), but a lot of things can be done to boost up a Unity (or UE4) render.
I mentioned light baking. You can also use reflection probes or even Screen Space Reflection to get better looking reflections. Ambient occlusion is a great way to increase realism.


Add objects to center of mesh faces using particles

Consider

Technique 01

Duplicate a ring mesh by itself with a particle system. Then move the ring to be coincident with the original sphere.  One sphere object for shape.  One ring object for particles.
For the duplicate ring, do not render emitter.  The particles remain.  Ensure the Particles per faces setting is value 1.  Set the value of number of particles.

Technique 02

See Duplication on faces.

Above the deleted faces of duplicator.

Above rendered image smoothed and using subdivision surface modifier.

Link

Tapering a tentacle mesh with uniformly scaled suction discs

If your particles are static you might even use the Array Modifier.


Camera Prespective under Animation screen layout showing mirror Image

I think you may have accidentally scaled your camera to a negative number. With the camera selected, open up the properties panel with N and see if the camera's scale is anything smaller then 0.

If you have scaled the camera, then just make the X axis a positive number again, and your render will work as excepted.

There really is no reason to have the camera scaled to anything but 1, except if you are looking to flip the image. However if a three axis have a negative number, after changing the camera's scale you will have to reposition the camera.


This is a partial solution. For simple scenes it'll work fine, but more complex setups will run into problems very quickly.
/*
 * Checks if, for this ray, the object is already inside the named object.
 */

    shader Intersects(
        string Container = "",
        output int Intersects = 0
    ){
        if(trace (P, backfacing() ? -N : N )) {
            string name;
            getmessage("trace", "geom:name", name);
            if (name == Container) {
                Intersects = 1;
            }
        }
    }

This shader returns 0 if there is an intersection with the named object, and 1 if there isn't.
It is adapted from a script by Secrop found here, as well as the Dipper script Robin Betts suggested to me from an earlier answer here.
I essentially just combined the two, while stripping them both down to the bare minimum. I'm not entirely sure, but I believe there is a bug with the getmessage() command. It appears to often do nothing, rendering much of the related logic unnecessary/redundant/ineffective. For instance, in Secrop's script, neither the backfacing() check, nor the material:index check(!) appear to do anything at all.
As far as I can tell, there are no such redundancies in this script.
That being said, it's entirely possible, I'm missing something here. Certainly, adapted from Robin's script, the call getmessage("trace", "geom:name", name); works just fine, so I don't know where the issue lies.
Workflow:
Here is an example setup.

Note, the deformed cutting cube also interacts with the sphere, to close it back up. Without that, the sphere would be missing some walls and it'd render more like a shell, rather than an enclosed surface.
Currently the setup basically has the cube cut out a piece of the sphere, equivalent to the Boolean "Difference". Using different variations of this node setup, you can also get it to work like various other Boolean operations.
Limitations:

The materials here are completely unchanged. As you can see, it may get confused in certain situations. Suzanne looks, like she partially is made of glass or something. Given how she's entirely made of diffuse materials, this certainly isn't supposed to happen. This must be the cube material getting confused about the location of the inside of the sphere.
Here you can see the same scene but with the roles of the cube and the sphere exchanged (just flip the mix shader input for both).

Note, Suzanne does not touch the sphere. If the script worked perfectly, Suzanne's chin would be yellow throughout. It shouldn't be view-dependent, but strictly about whether a mesh is inside another.
There may be ways to fix these issues, but I'm not sure how.
At any rate, that's the reason why this won't be the accepted answer.
The reason I put it as answer anyway is because for relatively simple setups, this will likely already work perfectly.
One simple workaround, that may, however, not always be feasible (depending on your situation), is presumably to have several such masking objects, none of which, I assume, may intersect, all of which affect the meshes they intersect in a uniform way. (For instance, if the setup renders glass walls for one object it intersects, it ought to do so for all objects.)
This next one I'm not quite sure whether there is an issue here:

In this variant, I made the cube, now clear glass, cut out a piece of the now diffuse sphere. To close the sphere, in the intersecting area, the cube generates a diffuse shader matching the sphere. Consequently, those faces will not be glass shader ones.
Now I'm not entirely sure. This would depend technical details. But does Cycles count this situation as escaping the glass to hit a diffuse mesh? Or will it think it was diffuse all along, making it more like the interface between air (vacuum) and this diffuse surface?
I'm not entirely sure it will actually make a difference, but I think it might: Namely in the case of total reflection. If Cycles thinks this is a glass-to-diffuse transition, the right setup, I think might cause total reflection, rendering the diffuse surface entirely invisible behind the internal reflection of the glass. If it rather considers this a case of having been diffuse all along, things will go wrong when internal reflections become important.
Unfortunately, for my ultimate use case, that would definitely be an issue. I'll have to see whether it works there.
Finally, I'm less concerned about it working with Volume shaders, but I did a few quick tests and it actually appears to work fine... To a point. It's certainly easy enough to make something look super weird.


The rendered images differ from the images in the toggle camera view

The difference is due to different lighting. Currently the viewport shows objects in studio lights but the rendering happens in sunlight. To see the rendered image in viewport: Change Viewport Shading to Rendered:


Painting a dog with texture paint, TOTAL NOOB

Firstly you need to unwrap mesh into UV editor in Edit mode.

STEP 1: Goto "Edit mode" in 3D viewport by pressing TAB key or using the menu below

Once you are in Edit mode like this

Drag the window below just like this

Now, follow the image below to go into UV Editor.

Then hit U in 3D viewport and press "Unwrap" in the menu from the image below

After the unwrap you'll get unwrapped mesh in UV Editor something like the below image.

But you can see that all the unwrapped mesh is overlapped in UV Editor in image no.5.
You have the same problem with the mesh.

Now the solution starts.

You need to select the vertices of the mesh so that when unwrapped it needs to be unwrapped good. Check out the reference cube image that has its vertices selected.

After the selection of vertices in the mesh hit Ctrl+E in 3D Viewport and select "Mark Seam".

Then hit select all the vertices A+8 x2times, after all the vertices are selected, Hit U and select "Unwrap".

Now, after the mesh is unwrapped correctly, create new texture

And continue your Texture Painting.


Strange bug with the Subdivision Surface Modifier

Check for faces inside the mesh. These are referred to as interior faces and they mess things up in ways similar to what's going on in your model.

One way to find them is:

Go to Edit Mode (Tab)
Make sure to deselect everything (A key)
Open the Select menu (bottom of the 3D Viewport window)
Choose Select All by Trait > Interior Faces

If anything ends up selected, hit X or Delete.

If that doesn't work, you'll have to hunt it down by hand. To do that:

Enter Edit Mode
Turn off your Subdiv modifier (eye icon in the modifier pane),
Delete a face near the problem area,
Rotate your view around and peek inside.

If you see an interior face, select and delete. And when you're done, of course, replace the face you deleted.


Cannot find the 'Manipulate Object Centers Only' button. Is this an addon?

I would post a comment to the above answer, but apparently I need 50 reputation for that so I have to add an answer instead.

The book the OP is referring to is "Blender Foundations: The Essential Guide To Learning Blender 2.6", by Roland Hess. I have this book myself and the text where the author refers to the Manipulate Object Centers Only is in a tutorial where we are trying to box model a simple chair. The effect he wants to achieve is to splay the 4 chair legs out from each other by selecting their bottom faces and using the scale tool:

  However, if you just select the bottom faces of the legs and hit the S
  key, they will move apart as you scale them up, but they will also
  grow in size. We'll try a new pivot style to solve the problem. Beside
  the pivot style menu on the 3D view header is a button called
  Manipulate Object Centers Only. This magical button causes
  transformations to only affect object centers, not their component
  structures. The effect works both in Object mode and Edit mode. In
  this case, selecting the four faces on the bottoms of the legs and
  enabling Manipulate Object Centers Only will move the faces away from
  one another when scaling without actually changing their size.

Note how he mentions the setting works in both Object mode and Edit mode, this seems to imply that we were meant to switch out of Edit mode to Object mode, switch the setting, the come back to Edit mode but he doesn't implicitly tell us this in the book. Having said this,  and after trying it myself this setting doesn't appear to do anything in Edit mode as the above users mention.


What Free 2D CAD programs can export to Blender?

I understand anything that will export/save 'SVG' files. SVG can be imported into Blender. There's quite a few questions about how Blender treats SVG in here.

An SVG option under save/export has rapidly become fairly standard for most vector drafting applications. I'm not up on the free stuff right now, so I'm afraid you'll need to do the leg work to find out which one's will save SVG files. Hope this helps.


Can I control an object using a driver with multiple inputs?

I got it working like I wanted to:

Upper eyelid

Just add both values (slider and ctrl_up) as variables and use Type: Minimum Value, since they are going from positive to negative and we want the smallest one.

Lower eyelid

Just add both values (slider and ctrl_down) but use Type: Scripted expression, and invert var2, so when it moves up, it still gives a negative number.

Here's the final blend:

Hope this helps someone with understanding drivers!


Struggling to model irregular rounded shape, any recommended tips/tutorials?

Assuming this is an exercise; that you're not wanting to retopologise the original in some radically different way..
This is a subdiv. model: the topology is a that of a Round Cube.
So, starting with 1/4 of one of those, mirrored left to right, and keeping the poly count at the minimum to capture the curvature:

.. just shovel the vertices around under proportional editing, while looking at the result under Catmull-Clark subdivision, level 2. You could use a more orthogonal reference, for accuracy.

Add a Solidify modifier for thickness, creasing the rim, and, after applying the modifiers, extrude the fillet.


Why does this geometry say "Nothing selected"?

I found the issue! Somehow I managed to hide all the vertices without hiding any faces. Unhiding everything with Alt + H fixed the issue for me.


As of Blender 2.83 (currently in alpha at the time of this post), this can be solved by using the "Adaptive Sampling" option in Cycles. Adaptive sampling will automatically stop sampling in areas of the frame that are no longer noisy. To enable it, check the "Adaptive Sampling" box in Render Settings > Sampling

Once adaptive sampling is enabled, the render and viewport samples settings become the maximum number of samples that a pixel can have. How many samples a pixel actually gets will be adjusted automatically based on how noisy it is. Once Cycles sees a pixel as no longer being noisy, it will stop sampling it.

Under Sampling > Advanced, there are 2 additional options, Adaptive Min Samples, and Adaptive Threshold. Both are set to 0 (automatic) by default.

Adaptive Min Samples dictates how many samples Cycles will take before beginning to check if a region is noise-free. Checking for completion adds some overhead, so you don't want to do it when the image is still hopelessly noisy. The default setting of 0 puts this in automatic mode, which will set it to the square root of the maximum samples setting. This is good enough in most cases, although if you're using a high number of samples (such as several thousand) and have blank areas in your frame, manually setting it to a value such as 32 may give some performance improvement.

Adaptive Threshold sets a metric that defines when a pixel is "no longer noisy". The default of 0 puts this in automatic mode, which is usually fine if you're using denoising. If you need to adjust it manually, smaller values correspond to less noise. For final renders, values such as 0.001 are common.

In this example image, adaptive sampling allows the render to finish twice as fast (10sec instead of 20sec) at 1024 samples while producing the same final image.

By enabling the "sample count" pass, you can see a "heatmap" of where Cycles needed to use more samples. Darker values show fewer samples, with the darkest being areas that stopped right away at the minimum number of samples. Brighter values show more samples, with white being areas that went all the way to the maximum number of samples.


I think you're complicating the operation, the 2 most basic ways to do it is with a Simple Deform modifier or with a Curve modifier.

With a Simple Deform modifier (easiest in my opinion):

Create your brick.
Give it an Array modifier with the count of brick you want, enable Merge and First Last.
Give it a Simple Deform modifier, choose the Bend mode, and an angle of 360°.
Your well will automatically be 8 bricks / 360°.
If you don't want the bricks to stick to each others, increase the Array Relative Offset value a bit and reduce the Simple Deform Angle (to adjust the first and last bricks).

With a Curve modifier:

Create your brick.
Create a curve. Put its origin somewhere on its circumference, put the brick at the same position as this point.
Give your brick an Array modifier with the count of brick you want, enable Merge and First Last.
Give it a Curve modifier. You will need to adjust the curve size to make the first and last brick stick to each other. When you scale, use shift to make it more precise.
If you don't want the bricks to stick to each others, increase the Array Relative Offset value a bit and scale the curve.


Can you change the bit rate or quality in general for .png formats while rendering?

PNG is not a lossy format like jpeg. It can vary the file size just with compression quality. Think of it as a zip packer. The more you set compression level, the more time it takes to compress, but the more compact file it produces, but after unpacking a file is the same. The compression level you can change in the output settings. Also PNG can be with or without alpha channel (RGBA / RGB). And also you can save 8 bit or 16 bit per channel color depth.
So, if you render to PNG, it's like rendering to bitmaps (BMP) and then compress them with zip. No quality degradation on any settings. Just time and file size - that's what you can play with.


My Lamp does not glow as I want. The lamp does not have a material properties section

I'm using Blender 2.9.1.0. Bloom is found under Render Properties when EEVEE is selected but not when Cycles is selected.


Remove "Preferences:" label from AddonPreferences, no bl_label to " "?

It's hardcoded in user prefs UI.
Agree it is a wasted line of space and have also looked into removing it.
Unfortunately the label is hardcoded in the user preferences space UI  and used in the USERPREF_PT_addons panel which displays the addons in the user preferences.
Snippet from scripts/startup/bl_ui/space_userprefs.py
# Show addon user preferences
if is_enabled:
    addon_preferences = prefs.addons[module_name].preferences
    if addon_preferences is not None:
        draw = getattr(addon_preferences, "draw", None)
        if draw is not None:
            addon_preferences_class = type(addon_preferences)
            box_prefs = col_box.box()
            box_prefs.label(text="Preferences:")  ## <<------ HERE
            addon_preferences_class.layout = box_prefs
            try:
                draw(context)
            except:
                import traceback
                traceback.print_exc()
                box_prefs.label(text="Error (see console)", icon='ERROR')
            del addon_preferences_class.layout

which shows how the label is added to the UI layout box to draw into, using the draw method of your addon preferences class.
Options,
can edit it out in code above, and save over the original. Wouldn't recommend changing the UI code this way.  Although in this case searching  for box_prefs.label(text="Preferences:") in script to insert a hash comment character could be offered up to the user, who like us would like it gone.
Override with changes.

Make a class based on this one, with desired edits,  and override by unregistering old, registering new, to override the old.
Silly example, image above. Re-write the draw method and reregister new class using it.
import bpy
from bl_ui.space_userpref import USERPREF_PT_addons

# unregister
if USERPREF_PT_addons.is_registered:
    bpy.utils.unregister_class(USERPREF_PT_addons)

def draw(self, context):
    self.layout.label(text="My New Addons Draw")

cls = type(
        "MyNewAddonsPrefs",
        (USERPREF_PT_addons, bpy.types.Panel),
        {
            "bl_idname" :  "USERPREF_PT_addons",
            "draw" :  draw,
            },
        )

bpy.utils.register_class(cls)

Related
How to re-register a built-in operator?
Note.
One very handy little "trick" shown in snippet above is how the layout of the userprefs is "monkey patched" onto your addon prefs class, so within your addon prefs draw self.layout is the UI layout box.


Multi extrude a vertex in the coordinate direction

I've uploaded on GitHub a script that allows you to extrude selected vertices in all directions.

https://github.com/parameciostudio/extrude-vertices-all-directions

You can set the amount and choose whether select created vertices or not.

How to install

Open up extrudeVerticesAllDirections.py in the Text Editor and press Alt+P

How to use

Select a mesh object and toggle into Edit Mode (Tab)
In the MISC tab of the Tool Shelf (T) you'll find a new Extrude in all directions panel
Set the extrusion amount and whether select new vertices or not (if not, original vertices will still selected)


AMD GPU Material in "material preview mode" and "rendered mode", is entirely gray as background. Only outline is displayed

Update: Blender 2.92.0, 2.91.1 and 2.83.11 will contain workarounds for the missing / incorrectly rendered surfaces of mesh, curves and metaballs as well as the incorrectly rendered wireframes caused by bugs in the graphics driver.

The graphics driver version Adrenalin 2020 Edition 20.11.2 and later appear to cause issues for several users, as reported in T82856 and related tickets. Installing a previous driver version should solve these problems until the bug in the driver is fixed or Blender provides a workaround for the problem.


How to achieve the perfect material for an aircraft glass canopy

Well let me say you that almost every jet has something called iridescence effect and you have tried hard to fake it but its ot a big deal to do  it you need to know that the effect of iridescence is created only in the border of the glass take for example this  and also the effect is minute in some angles but more visible in some , for the effect you need to use noise and hue saturation nodes. here is the setupand here is the result [3]
note if you want more colorful effect then reduce the factor of fresnel .also make sure to apply solidify modifiers to your glass . greetings !!!


In the current development version of Blender 2.82 the option can be found in the preferences. The Interface tab contains the Editor panel, which contains the Temporary Windows sub-panel, where the Render In option is located.


Blender ID Authentication - Issue with Login

If you have any issues, contact us at cloudsupport@blender.org. Stack Overflow is not the place for this.


Problem with particle system in blender 2.9

Are you using any kind of material based displacement on your emitter? If so, that could case the object to be rendert at a different position then in the viewport.


I'm sure there are multiple ways to do it.  Physics are unnecessary (which is nice, because it's faster and easier without them.)

We start with a root bone.  Then we have a rotation control, parented to the root  Then we have a deforming bone for the inner/middle section (depending on if you want the axle handled differently), which is parented to the rotation control.
Finally, we have the bone for the outer section.  This is the only constrained bone.  It is parented to the middle bone, but has inherit rotation disabled.  It is floored in both directions to our root bone, so it only moves side to side with the rotation of the inner body.
There are plenty of constraints we could have used to acquire this behavior.  I just happened to pick floor constraints.


Can I use Blender Game Engine (BGE) to create a simple interative movie?

I suggest to split the animation(s) into several segments. That means you have one ActionActuator for each segment defining the begin and end of the action to be played. E.g. start:1, end:200

To deal with each single segment I recommend to use a state of the build-in state machine. This allows to focus on the specific segment without creating too much spaghetti bricks.

Here is an example with two states. You can configure your ActionActuators as you like, but I recommend Mode:play

State A:

State B:

As you hopefully see the structure of each state is pretty similar.

when entering the state -> start playing
when the playing ends ->
transit to the next state (can even be the same one, if you want to
implement a loop.

And yes, you can transit to other states on any event you like, e.g. key press.

To get more details have a look at Action sequences with logic bricks - the power of the ActuatorSensor. It comes with an example.

I hope it helps


Figured it out don't worry!

I don't know how or why it worked, but I basically just tested a sample animation a couple of times using the same format above but in different blender files until eventually, (and miraculously) the borders disappeared on their own. It seems my Blender was a bit buggy.

However, I wouldn't recommend this if it doesn't work for an extended period of time, but mine luckily worked after 2 or 3 tries.


(Python API) Importing, Setting Pivot Point, Locating and Rotating

I suspect that all of the points in the geometry are relative to the origin, but that likely does not explain the problem you are experiencing.   I found this function on the web, it seems to move the pivot point without the problems you are experiencing.
import bpy
from mathutils import Vector, Matrix

def set_origin(ob, global_origin=Vector()):
    mw = ob.matrix_world
    o = mw.inverted() @ Vector(global_origin)
    ob.data.transform(Matrix.Translation(-o))
    mw.translation = global_origin

# call the function:
set_origin(bpy.context.object)


How to Change the Origin when moving a Collection Instance

First Method : Set the origin in the base collection

To change the origin of a collection instance, you have to go to the object information panel, then the collections foldout and choose "set offset from cursor" with the drop-down popup on the right of the collection name.

Second Method : Set the origin in the collection instance

There is another way to do it as pointed out in the comments. Select the collection instance and type F3 to search for "Set Origin" and choose accordingly to your case. Alternatively go to Object>Set Origin.

Note that this will be a bit more work if your object's origin is not in the center of its geometry. You can still manually place your cursor and choose "Set Origin" "From Cursor".


How can I make an animation of mesh pieces assembling (something like an explode modifier in reverse)?

Precondition
For this approach you will need the tiles as separate meshes (it doesn't appear to be your case).
To make an object into separate pieces (if they are already disconnected, but part of the same object), in Edit mode: select all the vertices (A), then P > "By loose parts". It's convenient to also select all the new meshes (that now share the same origin point) and do Object > Origin > Origin to center of mass.

Simple keyframed animation with a randomized starting point

Place your tiles in their final position.
Go to the last frame of the animation, select all the tiles, set a keyframe (I > "Location")

Go to the first frame.
Move the object to their average starting position behind the camera.

Hit Space for search (F3 in Blender 2.80), search "Randomize Transform".
In the tool parameters, adjust the "Location" values, especially along the direction parallel to the camera orientation.
Add a new keyframe (I > "Location")

Done! Final result seen from the camera:


When I move or scale objects, keyframes are being added

Seems like you accidentally enabled Auto Keying. In the Timeline, uncheck the first icon (the circle) of the animation controls :


UE4 - FBX -Blender not exporting animations

apparently a bug in blender 2.9
being investigated


In Object mode, select your object and press Ctrl+A, then select Scale.

This will make sure the Local scale of the vertices, match the Global scale of the scene.

This probably happened because you scaled your object in Object mode rather than in Edit mode.


You can control particles emission with animated Black & White Color influencing an emission Density.

In this example

particles are emitted from circle's vertices (but source can be Face or Volume as well)
by default are particles emitted all the time
with Texture (Color) you can influence density of emitted particles

Technically you don't let blender to stop / start emitting particles, but texture says how much dense particles should be emited. Black color means emit zero particles, White means full density of emitted particles.
Animation Sequence
Go to Particles Properties editor > Texture and ad New.
Switch tab to Texture Properties and select type Image, simply because it is black by default, so you don't have to setup nothing else. Just go to Influence panel and enable Density

Now you have two options

animate color from black to white or
I decided to animate Density parametr from 0 to 1

... means zero influence of black density - it let particle system emit as normal, one means full influence of black density that is zero particles.
If it is too overhead you can choose first option and in Texture enable Color Ramp and animate color. Result is the same.
Set one cycle of keyframes and go to Graph editor and change interpolation T to Constant that will works like switch ON/OFF in time.
Animation Repeat
To let blender repeat this animation open Graph's editor properties (side panel) N, go to Modifiers tab and add Cycles


How can I convert data from camera data node(view distance) into a file output(image or CSV or anything)?

Here's a small script that renders the scene and stores the Z_Pass into a CSV file, with {X, Y, Distance} in each entry.
All you need to do is paste this in the text editor and execute.
import bpy
import numpy as np

dest = 'C:/tmp/z_data.csv'
backgroundD = 10**10

def getCoordFn(x):
    def gc(i):
        return i%x, i//x
    return gc

def getpixelz(image):
    arr = np.array(image.pixels)
    pix = arr[0:-1:4]
    gc = getCoordFn(image.size[0])
    zpix = [(gc(i), d) for i, d in enumerate(pix) if d < backgroundD]
    return zpix

def writeCsv(data):
    with open(dest, 'w') as file:
        for p in data:
            file.write(f'{p[0][0]} , {p[0][1]} , {p[1]}\n')

def prepareRender():
    rn = bpy.context.scene.render
    rn.engine = 'CYCLES'
    rn.image_settings.file_format = 'OPEN_EXR'
    rn.image_settings.color_depth = '32'
    cl = bpy.context.scene.cycles
    cl.samples = 1
    cl.pixel_filter_type = 'BOX'

def prepareOutput():
    scn = bpy.context.scene
    scn.use_nodes = True
    bpy.context.view_layer.use_pass_z = True
    nt = scn.node_tree
    nt.nodes.clear()
    r = nt.nodes.new('CompositorNodeRLayers')
    v = nt.nodes.new('CompositorNodeViewer')
    nt.links.new(r.outputs['Depth'], v.inputs['Image'])

def execute():
    prepareRender()
    prepareOutput()
    bpy.ops.render.render()
    image = bpy.data.images['Viewer Node']
    writeCsv(getpixelz(image))

execute()

Note that this overwrites any setup you have in the compositor.


Multiple textures on a surface - transparency problems

Ah silly me, this node setup actually gives the correct results. The problem was that I had another material slot on the same surface which had an older incorrect transparency node setup (which was causing these problems)...

Here's a render with the above node setup showing no transparency issues!


Intersection of objects taking into account plane scale

In the end I did was to cast a ray, from that ray create a bisection with a flat plane, then I got the closest edge and vertex in the bisection from the ray hit position then explored the topology of the mesh getting only the vertices I could reach from that point:
# Perform bisection
        bmesh.ops.bisect_plane(
            bm,
            geom=bm.faces[:] + bm.edges[:] + bm.verts[:],
            clear_inner=True,
            clear_outer=True,
            plane_co=plane_co,
            plane_no=plane_no
        )

        # Bisection cleanup
        closest_edge = self.find_closest_edge(bm)
        vertex_list = self.get_reachable_vertices(closest_edge)
        for v in [v for v in bm.verts if v not in vertex_list]:
            bm.verts.remove(v)

Example of exploring topology:
    def get_reachable_vertices(self, closest_edge):
    edge_list = [closest_edge]
    vertex_list = [v for v in closest_edge.verts]
    for v in vertex_list:
        for e in [edge for edge in v.link_edges if edge not in edge_list]:
            edge_list.append(e)
            if (e.other_vert(v) not in vertex_list):
                vertex_list.append(e.other_vert(v))

    return vertex_list


Will this old method work for you ... using a prerendered hemisphere normal texture.

Basically I have attached a shadeless material of a normal rendering of a hemisphere. You will find the image packed in the blend file. Using a orthographic camera I render from the top view of the model. Also I have replaced the color of the background to a flat normal color which is (R0.5,G0.5,B1.0)

This is where you change the background color under the world tab on the
properties panel.

Hit the render button on the Render panel and you should get this result.

Let me know if you have further queries.


EEVEE and Cycles render lighting differences

TL,DR
EEVEE and Cycles are two completely separate render engines with very different approaches to produce an image.
You can't possibly expect to even remotely match a real time OpenGL based rasterizer with an unbiased path tracer image.
The long explanation
While they are very compatible to a certain degree, share most material and shader definitions; and the lamps and workflow are mostly interchangeable, they are very different under the hood, and quite opposite in very fundamental ways.
Both are aimed towards producing rendered images from a 3D model with varying degrees of realism, and both use a physically based approach to the definition of materials, but that is where the similarities end.
Cycles is a raytracer, a physically based unbiased path tracer, whose aim is to approach as closely as possible the real word physical phenomenon of light dispersion and interreflections through tracing of photon rays.
On the other hand EEVEE is rasterizer, a realtime OpenGL based render engine, compatible with PBR material creation. It has support for baked indirect lighting, screen space reflections, screen space ambient occlusion, and other modern commodities provided by current generation graphics hardware. While it is quite advanced and has extensive features to increase photo-realism it is easy to forget that at the end of the day it is still at its base a rasterizer (the most basic form of rendering computer graphics), with main purpose being speed and responsiveness over realism.
With this in mind it is virtually impossible to make a render made in EEVEE match one made in Cycles. Renders made with different engines would be very hard to match even for slightly different implementations of the same algorithm, let alone for two so fundamentally different rendering approaches.
You can't possibly expect a real time OpenGL based rasterizer to even remotely match a unbiased path tracer.
EEVEE

Cycles

This is easy to forget because both are deeply integrated into Blender, with a lot of common settings, having a similar workflow, sharing most material definitions and texture settings while using the same node tree based shader definitions. These similarities are very superficial, mostly at UI level however, under the hood very different calculations are happening and a whole lot of work has been put to make them work so well in tandem, and make their outputs match so closely.
Work is constantly being done to make the transition between the two as smooth as possible. Results are tweaked so that light intensity and material properties match as close as possible. Don't expect miracles however, there will always be differences between the two.
If EEVEE was ever able to produce the same results as Cycles at a fraction of the time we wouldn't really need raytracing at all, and Cycles would quickly become obsolete.
Here a few current limitations or real time rendering. EEVEE can´t really handle environment shader occlusion, HDRI world maps can't generate shadows and reflections are always visible regardless of occlusion, without baking. Most reflection types require baking for correct results, and don't handle interreflections too well. Transparent objects often can't be seen through other transparent objects and consecutive refraction effects don't carry over.
Solutions
Luckily, as user L0Lock mentions EEVEE and Cycles shader trees support multiple material outputs, and each can specify different target render engines within the same material, meaning you can tweak shaders to compensate for each render engine without having to make separate materials or fully rewrite your node trees.
Just add two Material Output Nodes to your shader tree, pick the render engine from the dropdown menu, and adjust your shader tree accordingly for each, diverging only where adjustments are required.

For lights, nodes are not yet supported in EEVEE, so if your lamp uses a node tree then EEVEE currently ignores it, virtually allowing you to tweak Cycles result from the node tree, while EEVEE will always display the direct result of the lamp at Object Data level properties, meaning you can independently tweak viewport results from the Properties Window parameters while Cycles uses the nodes one.
Otherwise if the results don't match well enough I'd advise creating two separate scenes, link all objects and data, then make unique users on a case-by-case basis for each single lamp or material that needs individual tweaking.


I figured it out. What you do, is you go over to your toolbar, and you hit "set handle type" then you can go down to the menu that popped up as a result of hitting it and change the handle type to your liking.
The shortcut for this is "V".


Shape On Animation Path Is Wobbly And Shape Not Facing The Right Direction

If the cube is not animated, the wobbling should be only due to realtime viewport delays, but a true render should be fine.
When you parent or constraint a follow path function, Blender creates a modifier inside the graph editor, generating a straight infinite line. You can delete the modifier and add manual keyframes on the path animation properies tab, knowing that the number of frames (100 in my example) is the value needed to complete the curve, and the evaluation time is the value of the keyframe (so that 50 will mean half path, 33 one third, and so on).


Numerical value of keyframe in the Graph Editor

Show Sliders

From the graph editor view menu toggle view sliders

Now each fcurve has a slider in the channels region.

When the scene frame is on a keyframe, highlighted yellow, updating will change the keyframe value. When green, will add a new keyframe at that frame.


Shading problems,tris mesh with black marks

Looks like Shade Smooth is on. If that is the case, try switching the shading to Flat (Object Mode > Right Click > Shade Flat), or turn Autosmooth on (Object Data Panel > Autosmooth).


How to set 2 different material front back to a mesh

I'm not sure why you're using a Transparent node. Plus contrary to what you say your cape has thickness as you've given it a Solidify modifier. So you need to either apply or remove the modifier. Your node organization must look like that:


You can use the wm.tool_set_by_id() operator.

Example for a button:

layout.operator("wm.tool_set_by_id").name = "builtin.select_box"

Example operator:

import bpy

def main(context):
    bpy.ops.wm.tool_set_by_id(name = "builtin.move")
    for ob in context.scene.objects:
        print(ob)

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

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

    def execute(self, context):
        main(context)
        return {'FINISHED'}

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

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

if __name__ == "__main__":
    register()


Is there a way to export each render layer seperate but as animation?

Yes this is possible, for this you will need to use the compositor.

Activate use nodes and delete the composite output node.
You will be left with a Render Layers input node.
Create a copy of this node for each render layer you wish to create output, and select a separate render layer for each node.
Connect a File Output node to each Render Layers node using the yellow image connection dots.
Create a separate output path for each file output node.


Create animated textures in time with the music in blender 2.81

Check HERE or HERE Animation Nodes Scripter


Measure length of "curve" (or similar) by drawing on mesh

Nevermind, found my solution here:
How can I make curves "stick" to a model?
Instead of drawing a selection and then creating a curve from that, you can draw your curve and have it snap to the object as you're drawing.


Curved glass reflections in Glass material

The simulation of refraction depends on light rays being bent twice. Once on the way into the glass, via a front-facing surface, and once on the way out, through a back-facing surface. Your 'good' glass has thickness, so it works. Your 'bad' glass doesn't.
No thickness:

With a Solidify modifier: (No rim. 'Fill' unchecked, so as not to bother with normals interpolating over the rim walls)

If you want a rim on your glass, you will have to bevel it too, to sharpen the interpolation of normals from rim to surface.


Can I access a mesh's local vertex positions in Cycles Nodes?

You can easily use use the Object texture coordinates from the Texture Coordinates node to achieve this.

The socket will output XYZ values in object space, than can be used as RGB values or mapped with a Color Ramp node.

All you have to do is use a Separate XYZ node to get the Z component of the coordinates, and optionally a Math node set to Absolute so you can easily have symmetry along Z, if that is what you wish to achieve.

Taking this a step further, you can calculate the distance as sqrt(x^2 + y^2 + z^2) (and remove the Absolute node) as follows :

Feed this into a 'Multiply' Math node to allow you to scale it as necessary and link this into the Color Ramp.


I found a fix! Apparently my normals were facing the wrong way. You can check this by clicking on overlays and checking "Face Orientation"; Red means it is reversed. I Selected all my vertices and hit shift-n and voila no more silvery things! Thank you everyone who gave suggestions.


Okay I looked at your file. There are some major problems, you are working on your lighting too soon. You have no materials applied to any of your objects. You need at least a basic material to setup lighting. Also your camera isn't placed very well to catch the action, it is barely getting the barrel at all. Fix these first then try to get the lighting. I would use a sunlamp, not the spot lamp.


What does the icon to the left of the object name in the outliner mean?

If you examine the "add objects" menu, visible by using the SHIFT-Akey combination, or the  Spacebar > Akey sequence, you will see that the icon to the left of "stem final copy", and "stem_final" in the excerpt of the image of the outliner panel you link to is used for one of three object types: an empty object, a force field, and a group instance. None of the three is a mesh, and so cannot be part of a boolean operation, as these take two mesh data.

You can create something equivalent to an empty by adding a mesh object, and in edit mode selecting and then deleting all of its vertices, but I don't see in the Blender Manual any information on converting an empty, force field, or group instance to a mesh.


Switching colors of a texture painted texture

When texture painting, you can change the active colour in the brush settings which can be found in the toolbar region by pressing T.

You have two colours available under the colour wheel, press X to toggle between the two while painting.

While it hasn't been added to the manual, you can create palettes of colours to easily switch between common colours. You can find some info about using palettes at the bottom of these release notes.

After you have finished painting one of your colour versions, go to the UV/Image editor and save a copy of the texture image with a unique name so you have each version available later.


How to UV unwrap multiple animated objects at once

Follow these steps and you should be able to get this done.

Add a camera to the scene that points in the direction you want to project the texture. (Optionally, make it orthographic.)
Select all of the cubes you want to apply the texture to.
Run the simulation until you get to the frame where you want to apply the texture.
Add a UV project modifier to the active cube. Under the Projectors field, pick the projection camera you added from the list of objects.
In order to make sure that the image is being projected at the correct size, switch to Blender Render and the Textured view mode. In the N panel, set Shading to Multitexture and check Shadeless. This will let you preview the texture mapping independent of any material settings.
In the UV project modifier, pick the image you want to project from the list and check Override Image.
Press CtrlL to Make Links between the active and selected objects. You want to apply the UV project modifier to all the active objects so pick Modifiers from the list.
Make adjustments to the UV Project modifier in order to get the projection you want. You will need to re-link the modifier to the other objects after each change.
When you're happy with the results of the modifier use AltC, convert to Mesh in order to apply the UV Project modifier to all of the cubes.
Set up a material that uses the texture you're projecting and use CtrlL to link the materials to the other cubes.
Render out the image sequence and bob's your uncle.


Make sure to have texture created with "Node Editor".  This is the basic node for texturing in Cycles Render.

From 3D View, toggle to Node Editor -- make sure to toggle "Use Nodes"


  If the Mouse Sensor is set to Left Mouse Button, it will simply register if the mouse button is pressed, regardless where you do it.

  You can combine it with a Mouse Over Sensor and use an And Controller. Then the Actuator is only triggered when the mouse is over the right object and LMB is pressed.


You can use a mask strip modifier:

In the above example scene1 contains a cube, scene2 contains a Suzanne, and mask_sequence is a black and white mask.

The mask modifier can use either a mask or another VSE strip to modify the transparency of the modified strip according to the darkness of the mask. If you set the blend type of the modified strip to Alpha over, the strip(s) underneath will show through the transparent parts.


Where to start with UVW files and adding them to a object

You don´t add them to an object previously treated with uvw maps. If they are present and not knowing what kind of obects is, is somewhat difficult. But, you can check the uvw maps appplied to the object in the corresponding uvw editor in Blender. For that you need to go into edit mode and select all the faces as shown in the screenshots.
In order to select all faces and don´t miss anyone go into wireframe mode which is the first sphere in the shade view as shown in the second screenshot in the upper right part of the screen. .


The mix node is for mixing different shaders, or materials, not different parts of one material. To add the "Texture" effect you want, I took a look at your file and reconfigured your shader to use a Bump node.

First, within the Chocofur_Fabric_Basic material, I removed the overlay node (unnecessary) and replaced it with a Bump node, routing the Main_Color input directly to the shaders and the Bump into their respective Normal inputs.

Back in your main material node setup, I removed redundant nodes and hooked the sideways skirting color into the Main_Color input of the fabric shader and the Chocofur texture image into the Texture_Input input of the fabric shader.

Here is the final Blend file:


In the graph editor or dope sheet select all of the keyframes you want to delete and then you can delete all selected items at once.


You could use the bridge function of the loop tools add-on if you have it enabled. You can find it under user  preferences> add-ons if you don't. In the attached gif I used a curve for the handle of my cup, and a cylinder for the cup itself. Press  Alt+C  to convert the curve object to a mesh object, then  Shift and RMB to select both objects. Then press  Ctrl+J to join your meshes. Now you can delete the unnecessary faces, and bridge the appropriate edges. To do so, use  Alt+RMB  to select your first edge loop, then Shift+Alt+RMB to select your second edge loop, and click bridge under the loop tools options.


Invisible Physics to Certain Objects in the BGE

You can do this with collision mask and collision group.

These options are found in the physics panel. To fix your particular problem, select the invisible collision box for the player and put it in collision group 2.

Next, select the bullet and while holding Shift click on the 2nd box in collision mask. This will stop the bullet from colliding with anything in collision group/layer 2.


How to select only camera's across multiple scenes in bpy?

Always looping over context scene's objects.
Logic error, you were only ever looping over the context scene's ("the first ones") objects.
Test code below, selects all and only camera objects.  Sets the scenes camera as active for each viewlayer.
import bpy
for scene in bpy.data.scenes:
    bpy.context.window.scene = scene
    for ob in scene.objects:
        ob.select_set(ob.type == 'CAMERA')
        # set scene camera to active for each viewlayer
        if scene.camera:
            for vl in scene.view_layers:
                vl.objects.active = scene.camera


Why is there no color in my lava material?

You need to enable Displacement Only or Displacement and Bump in the settings for this material.

Also your AO node is currently connected to the Material Output.


You can try this way.

Add -> Mesh -> Plane

Select the Multires mesh and in the Mirror tab -> Mirror Object-> Plane

Select the plane and adjust the center part moving the plane in x axis in my condition


This Pink Material shows that you added an Image-Texture without adding an Image. Go to Node-Editor and check your Material properties (Added Image correctly? Connect all Shaders and Outputs?)

Use the small Button in the corner down on the left side and choose node-editor.

I made an example for how the "Node-Tree" should be although you should choose the "UV" output from "Texture Coordinate" if you've wrapped your Mesh (Not Generated as I did).


Continuous Looping animation - Differing rotational speeds

Driver Based approach.

For the planet I have added a driver to its z rotation.

 pi * frame / 40

where frame is known to the driver namespace as the current frame. The rotation is 0 degrees at frame 0 and 360 degrees (2pi radians) at frame 80.

A satellite object and an orbit circle is added. A follow path constraint, with follow curve and fixed position.

The driver is added to the offset.

(frame / 40) % 1.0

At frame 0 and frame 40 will be at 0 and 1 offset (same position) respectively.  The % is python modulus, ie the remainder when divided by one.  Related

Ok so now have a planet that revolves once in 80 frames and a satellite that orbits every 40 frames.

To loop the animation, set 1 and 80 as start and end frames.


How to convert sapling leaves to linked duplicates?

Getting the location is very easy but getting the rotation is not.

I don't know if you need the leaves to be rotated exactly as sapling generates them, but there is another way to achieve a very similiar result (if not even better) and have all leaves instanced.

Go into edit mode -> select all faces -> press P> By loose paths

To recalculate origins, press ShiftCtrlAltC and select Origin to Center of Mass

Now link all the objects to one leaf with CtrlL

Before the next step, it is important to hide everything because we will be using Proportional editing in object mode to randomize the rotations

Turn on Proportional editing (blue circle or shortcut O) and set its Falloff to Random

You also need to set the Pivot Point to Individual Centers

Then it's time to rotate either way you wish, rotation of the other visible objects will be randomized. This is the result after hitting AltH to unhide the trunk

This step is just an extra, to hide all the dotted black lines (relationship lines) you can uncheck them in the 3D View's N menu under the Display tab

This is it!

Could you elaborate why you need this? Maybe there's a different solution to the problem and this is an unnecessary step. For example you can get the rotation data through Geometry > Normal in the node editor for setting up materials.


Don't run the script directly, instead, you can import the textblock as a python module, and execute a function it defines.

import myscript
myscript.main()

There are some caveats:

The script name must be unique to avoid colliding with existing Python modules.
You will have to define some function in the module to run.

But the advantages are:

Faster (no need to re-parse the script every time), (the compiled bytecode is kept between executions).
More flexible since you can pass in arguments if you like, and have multiple functions too.
The ability for variables to persist between executions (the module could contain a counter for example that increments each time. or values could be cached to avoid re-evaluation each execution).This is also something to watch out for, in case you accidentally re-use global lists, dicts etc...
More useful exception messages (__file__, __module__ for example will be defined)


Displacement Modifier and Texture Coordinates

Local is when you are using the object's own XYZ coordinates, regardless of it's placement in the global coordinates. For example, When you rotate an object in object mode the object will no longer be aligned with the world

Global has to do with the XYZ grid that starts in the origin 0,0,0. The transformations occur using the world's coordinates.

Here's a small example of how If your object is not aligned with the global coordinates you'll get different results using the displace modifier:


How do you rig and orbit an object while it follows a path simultaneously?

Ok, here's what I have so far. I'm still trying to work on the keyframed rotation start, but the object keeps staying in the same place when everything else keeps moving.

Here is the base setup. I used a simple flattened cylinder as a disc, two bezier circles, one of them scaled by 10 in edit mode, and another cylinder I made skinny and transformed/duplicated in edit mode so it becomes one object comprised of 2 cylinders sitting on either side of the disc. I made them all in the center because that way I could be assured they all have the same origin.

I parented the small bezier circle to the flattened disc, and applied a Path Follow Constraint to the two-cylinder object, pointed at the small circle. I set it to follow curve, and noticed that this changes the transform for some reason. I simply went to edit mode, selected everything, and moved it back over the flattened disc (for me it was simply a 1 unit transform on the Y, I think). Anyway, once it was back over, I Animated the path.

Then I selected the flattened disc and added a Path Follow pointed at the larger curve (which represents your main path). I checked Follow Curve, Animated the path, and presto - two cylinders rotating around the center of a disc that is moving around the scene.
I know this isn't the final result you're looking for, but you requested my steps up to this point, so there they are.
I'll upload the blend, in case you want to have a look. It's nothing special. I'll also keep working on how to keyframe the cylinder rotation start delay (assuming that's the part you want delayed). I'll post an edit to this answer if/when I find it.
File is here -


What is the best way to distort the shape of this leaf image plane? (i'm a complete beginner)

have not used Blender much in a long time either but hope this is what you're looking for.
I screen captured your leaf image used it as a reference to model a grid around it deleting the excess, made a material to map the image to the leaf, did a quick UV map , set displacement to bump, went into shading and changed settings to distort the surface.

rendered single leaf and it looked good , in object mode duplicated it nine times , took each leaf into edit mode > sculpt mode and used the elastic deform tool to distort the shape from flat plane.

I rendered both sides this is the bottom so it seemed to work good.


Don't bother to do your animation work in Blender. Unity's animation tools are quite robust, and animating in Unity will make it easier to make different animations and behaviors for one model.

Blender behaviors like showing and hiding can't be translated accurately into Unity behaviors. So even if you had it working in Blender, you would have more work to do once you import it into Unity.

Just export what you have in Blender WITHOUT any animations and put it in Unity. Drop the model into your Unity scene, then open up the Animator. Click the dropdown under the record button and select [Create New Clip].

To show and hide your cube, go to the appropriate frame of the animation, then enable/disable its Mesh Renderer. This will automatically add a keyframe to the animation clip. Do the rest of your animation as you would normally, adding rotation keyframes and such.


Shortcut to toggle a specific combination of layers?

The only way possible would be Shift+2+3+4, I think.


Is there a way to reset the camera to avoid clipping?

If you press Num . (dot on numpad) Blender will center 3d-view around selection, and move view as close as it possible with considering of
cliping settings and size of bunch of selected objects


Where is the brush selector of grease pencil?

The manual is for 2.78 which is not official yet...but can be test driven. Check your version before looking for functions that might not be in previous builds.
Brushes become available once you start drawing, or click on one of the drawing buttons in the Grease Pencil Tab - in the Tool Shelf.
You can adjust the colour on the other side in the Properties.


It's not really a different style of armature.  It's just an armature without meaningfully placed bone tails.
The essence of a bone, for skeletal animation purposes, lies in it having two characteristics:

An origin about which it can rotate (and/or scale; translation doesn't really need an origin);
A hierarchical structure from which it can inherit a transformation from its parents.

To do those two things, you don't need bone tails.  And in fact, many skeletal deformation systems have no conception of bone tails-- their bones are points, not lines.  The only thing you need for a bone is the head of the bone.  This is common in game engines, where any unnecessary data is scrubbed out in the name of efficiency, and that's why you're going to see game rip models without meaningful bone tails.  The game never stored their tails, because it didn't need them.
That doesn't mean that meaningfully placed bone tails aren't useful in Blender.  In Blender, bone tails do three things:

They establish bone length data for autoweights and bone envelopes;
They, along with bone roll, establish per-bone local axes;
They act as an extra pocket of information that you can use with bone constraints.

All three of those things are very useful.  Autoweights are a great start on weights that save a ton of time.  It is a pain to fix an A-pose arm twist bone when its local axes are oriented with the world axes at rest.  And good luck creating even a simple leg IK without a meaningfully placed shin bone tail.
However, if you want, you can work with an armature like this.  You can weight paint manually.  You can create non-deforming control bones to deal with constraints, or just not use any constraints.  You can pose it entirely visually, never limiting rotations to any local bone axes.
It's just, you lose out on some easier ways of doing things by ignoring your bone tails.


Several add-ons throw error "DLL load failed. %1 is not a valid Win32 application."

Try the following:

Close Blender
Rename C:\Users\YourNameHere\AppData\Roaming\Blender
Foundation\Blender\2.79 to
C:\Users\YourNameHere\AppData\Roaming\Blender
Foundation\Blender\2.79.bak
Use your login in Windows instead of YourNameHere and your version
of Blender instead of 2.79
Start Blender again


Eeeeeeh… that answer sounds horribly complicated to me!

Assuming you are getting mouse coordinates from event e (from invoke or modal callbacks of an operator), and assuming that operator runs into the main ('WINDOW' type) region of the UVEditor space, something like that should work (code not tested):

region = C.region
reg_x, reg_y = e.mouse_region_x, e.mouse_region_y
img_size = C.space.image.size

uv_x, uv_y = region.view2d.region_to_view(reg_x, reg_y)

img_x, img_y = uv_x * img_size[0], uvèy * img_size[1]


That's because the scene camera was set to the mesh itself, instead of the Camera:

Just imagine: Can you see your own face without a mirror in real world? :P

Solution is simple: Go to Scene tab (located in Property Editor), use the actual camera object instead of the default one. Or select the camera object then press Ctrl Numpad 0 to set it as the active Camera to the scene.

Another issue in this case is that the Aperture type of the camera was set to Radius, which makes everything blurry with current parameters. Or you can simply switch to F-Stop to solve the blank render issue:


How to break a voxelated object into voxels?

The Remesh modifier is made for modeling the surface only. Despite the look could appears quite similar, they are not voxels. It's probably easier to look for another workflow such as...

Particle system - Grid

From the manual:

  Particles are set in a 3d grid and particles near/in the elements are kept.

The emission algorithm automatically kill the particles outside the mesh (it must be watertight for correct results). Then you can just duplicate a cube in each particle's location as shown in the picture below.

In order to get the cube size that allows no gap between faces you must take into account the reference object bounding box's size and the grid resolution parameter.

In the provided example, for a cone that stays inside a cube of 1 unit and a resolution of 100 particles, the cube size is 0.01 units.

And here's a Suzanne made of cubes splashing on the floor:

EDIT: ADDED BY OP

For those who can't figure out how to make those particles behave well physically:
Is there a way to make particles behave like rigid body objects?
Look at the answers by WChargin and MarcClintDion.

In a nutshell, the generated blocks are particles internally, so they will always behave like points, dimensionless. But we want the boxes to behave like real cubes, don't we? So, we extract (generate) real objects from those duplis, by doing this:

Now that they are independent objects, we enable  physics on one object and copy it to all the rest by doing this:

Done.

By the way,
If, for example, you are making them fall on a floor and letting them scatter away, some might pass through the plane, as in the OP's case. So you should increase the (floor) plane's collision margin until no cube passes through.
If it is apparent that cubes are not actually touching the floor due to increased collision margin, then you can change the plane's origin to make them look like they are really hitting the floor.