Using VideoTexture.ImageRender to get camera image

Okay. I looked into the source code of Blender and it seems that ImageRender only works when rendering to a texture and it is not the currently active camera.

What I did was to add an additional plane, create a material along with a texture rendered it to that plane. After that, I was able to store the image.

In addition to that, I set the new camera as the active camera for the scene. Hope that this answer will help other people.


How to make a mask for voronoi texture (with randomness)?

The new Voronoi texture conveniently gives you a 'Position' output, which gives you (in 2D ) the X and Y coordinate of the center of a shading-point's cell.
So, if you don't want to cut your circle-'pixels' in half, you can use the distance of the whole cell from the texture space's origin to create a mask of whole cells, rather than the texture space itself.

I've scaled the whole texture down, so the cell-resolution is high enough to capture some circular curvature.


Well this is resolved.  I realize that I had the red item inside the block of glass marked to not render.  Sorry folks!


Tricky Curved Hardsurface, suggestions? (mandalorian helmet)

In my opinion it would help if you had a side view, and use both images as background.

Begin with the right side, build a very simple topology that follows the lines. Switch to front view, move the vertices one by one to make them fit to this new view.

Fill the faces, add edge loops to sharp the angles.


Material Properties-Material Preview doesnt show anything ( totally black)

it might be your graphics driver, I recently updated mine and had the same problem but when I went back to a previous version it's fixed


Despite weights being painted correctly, mesh moves in weird ways when I try to animate bones

You have overlapping vertices, so go in Edit mode and merge by distance. You'll maybe have some corrections to do though.


How to extrude equally in all directions?

The extrude tool can be pretty confusing when you want to do something simple like this, but if you use the 'Extrude Region (vertex normals)' function in the Tools > Mesh Tools menu, you can do it. However, there is another tool that can handle your problem - 'Shrink/Fatten'.

What I do is extrude (e), but without actually moving the extruded faces (to cancel the move hit esc), then use shrink/fatten (alt+s) to move the faces along their normals.

If you use Shrink/Fatten on its own, it won't actually create an extrusion, but can be used to move any existing face, edge or vertex along its vertex normals. I find it much less fiddly than invoking extrude along normals from the menu.


How do I create a squeeze tube packaging?

In this case I would not go with Curves as they aren't best choice in terms of modeling in Blender. My method is based upon simple plane which gives us very simple base geometry and allows to have nice top part of model. Starting with circle will give massive headache to close and straighten up this part of a mesh.

This is method I've used to model it:

Add a Plane - Shift + A > Mesh > Plane.
Go to Edit Mode.
Select all vertices, press E and extrude along Z axis.
Select top edge and press S > Y to squize it.
Extrude top edge along Z axis once more.

You should have now something like this:

Add Modifier > Subdivision surface and set it to 4-5 (preview and render).

Now we need to crease some edges.

Select all top vertices and set Mean Crease to about 0.6.

Do the same with bottom vertices but this time Mean Crease should be 0.3.
Add Loop Cut (CTRL + R then hover cursor over mesh) to 'main part' of the mesh and place it near bottom edge.
Choose Smooth Shading. Object Mode > Tools Panel (left side of the screen) > Shading > Smooth.

Here is blend file to play with:


How can I make a linked duplicate path with other bevel object?

Thanks to Mr.Zak's kind comment, I more or less solved it. I even threw in the twisting of the wires :)
The final solution does not use Bevel objects, but screw and curve modifiers.

In short:

for the wires, I made an object "KNX-wires" that consists of 4 circles
for the sheathing, I made another object "KNX-sheathing", that consists of a single circle
I added a curve "KNX-Path", to define the path of the cable

I then added the following modifiers to "KNX-wires" and "KNX-sheathing": screw, curve (with "KNX-Path" as curve object), solidify (to give some thickness), and a subsurf to finish.

Result looks like this. By changing "KNX-Path" in edit mode, the cable's path changes. By sliding the "KNX-Sheathing" and "KNX-Wires" along the Z-axis, they slide along "KNX-Path" following its curve. By changing the "screw" parameter of the screw modifier, I can change the length of the sheathing and wires (making the wires stick out a bit for instance).


Multiple materials on subdivided face resulting in displacement

The Bevel modifier is subdividing the mesh again creating new face which are assigned to a certain material depending on there creation method , changing the number of segments to an even number will get you the desired result


Remapped keyboard keys don not work properly in Blender only (Windows 10)

Solved, I needed to remap the virtual keys, to the proper scancode.
Did that manually editing the .klc file, because I found no way to do it in MS Layout Creator.
Then I just used the Creator to generate the setup files, from the edited .klc .

Detail by example:

I have physically switched the z/y keys on the keyboard
I have used MS Keyboard Layout Creator to alter the German keyboard
so as to type "z" in scancode location 2C (View this webpage
for scancode / virtual key settings by locale)
I have named the custom keyboard that matches my physical layout
"Deunglish" However because Deunglish started of as a German
keyboard the Virtual Key VK_Y is still mapped to scancode location
2C, despite setting this as an English keyboard with Creator.
Open the Deunglish.klc file with Notepad++ (or other editor) and
replace "y" (virtual key name) with "z" for scancode 2C.
Now you will have two definitions for VK z, assigned to two
different scan codes, in this case scancode 15.  Change that to y as
you did for z.
Load the klc file in the MS, verify and Build DLL and setup (If you
had been using the keyboard you have just edited, you need to unload
and uninstall the previous version first.  You will likely need to
restart)

You have successfully swapped virtual keys and assigned them to positions on the keyboard!
Do this for all keys that may need proper virtual key name to actual output matching, and/or to set to virtual keys to new scan codes.


Rigify rig main properties and rig layers disappeared

Open a Text Editor and see if there is rig_ui.py file there.

If there is click Run Script and check also Register. Your controls in N panel should reappear. Also make sure for future that you have Auto Run Python Scripts enabled in User Preferences under File tab (so the registered scripts are run automatically when you open blend file).
If you linked the rig into a new file, look in the original file if there is one. Both the rig and it's script need to be linked.
If there is none script to find anywhere, you need to make a new one. Create another blend file, create some rigify rig there and copy the script.

There is however a complication, each Rigify generated rig has a unique id, that matches with the script file, so the script we took will have some new random id and won't work with the original rig. Making these codes to match solves it:


How to find collections where an selected object is linked to?

There are at least 3 solutions:

If you select the object, go in the Properties panel > Object Data > Collections, you'll see the collections the object is part of:

In the 3D view if you select the object and press ShiftG > Collection, it will display the collections the object is part of:

If you select the object, in the Outliner you'll see an object icon enlighted next to the collections that contain it:


Must Vertex Group Edits Remove Current Before Assigning New?

As it turns out it seems it is just bad wording of how the controls are labeled. When it says "remove" for a vertex group it does mean that. When it says "assign" it is misleading...it should instead say "add" or "insert".

I do wish there were another button "assign" which would set the vertex group state to the current selected set of vertices...removing ones previously selected but not currently selected.


Why changing camera's far clip does not seem to clip the distance for depth map rendings?

This is essentially just a matter of interpretation and intended meaning. When the depth reports 10000000000 it’s not actually intended to represent an actual distance, rather ‘infinity’ (but it’s a suitably large enough value to essentially be regarded as that) and so it represents the rays not actually hitting anything. The camera clipping distance is effectively a tool to allow the render to be optimised (so we don’t consider details that are too distant to make a noticeable difference to the final render. It does affect which surfaces are considered for rendering but the ‘infinite’ depth is still relevant to indicate ‘nothing was hit’.

When interpreting a depth map it’s much clearer to interpret a single value (“infinity”) as an indicator that nothing was hit than a ‘variable’ value based on the camera clipping distance - maxing out at the clipping distance would require additional knowledge as to what the actual clipping distance was set to for that particular render before you could determine whether a point hit a surface or not.

If you know your clipping distance you should be able to manually limit the upper bounds with something like `min(9999,max(R))’ - ie, get the maximum value from R and then take the minimum of that and some constant based on your clipping distance.


Is it possible to copy data from one scene and paste it into another within the same .blend file?

There are other ways to get data from another scene:

A) when you create a new scene, you're given several choices:

(taken from the relevant manual section)
"

New Creates an empty scene with default values.

Copy Settings Creates an empty scene, but also copies the settings from the active scene into the new one.

Link Objects This option creates a new scene with the same settings and contents as the active scene. However, instead of copying the objects, the new scene contains links to the objects in the old scene. Therefore, changes to objects in the new scene will result in the same changes to the original scene, because the objects used are literally the same. The reverse is also true.

Link Object Data Creates new, duplicate copies of all of the objects in the currently selected scene, but each one of those duplicate objects will have links to the object-data (meshes, materials and so on) of the corresponding objects in the original scene.

This means that you can change the position, orientation and size of the objects in the new scene without affecting other scenes, but any modifications to the object-data (meshes, materials, etc.) will also affect other scenes. This is because a single instance of the “object-data” is now being shared by all of the objects in all of the scenes, that link to it. This has the effect of making a new independent copy of the object-data.

Full Copy Using this option, nothing is shared. This option creates a fully independent scene with copies of the active scene’s contents. Every object in the original scene is duplicated, and a duplicate, private copy of its object-data is made as well.

"

B) You can link any object from one scene to another.

As this other "Make Links" manual section says

"
Links objects between scenes or data-blocks of the active object to all selected objects. In some case (i.e. Object Data, Modifier) the target objects must be of the same type than the active one or capable of receiving the data. The existing data-block of which will be unlinked from them.

Objects to Scene... Lets you create links to the selected objects into a different scene than the current one. A scene name must be chosen other than that of the current one. The Link Objects to Scene Operator panel lets you choose between scenes.

This makes the same object exist in two different scenes at once, including its position and animation data. The object’s origin will change its color.

"


How do I set the Vertex color from a loop?

Enabling Deep Copy option in the Object Instancer node solves the problem. Vertex colors are property of meshes, thus in order to have different colors for different objects, their meshes have to be independent (Different copies of the source mesh), which is what Deep Copy do.


How to use Bend Modifier to create perfect polygons, (pentagon, hexagron, septagon, etc...)?

That'll be the Screw modifier, operating on a single vertex mesh at (radius) away from its object origin?


Soft Body object going through object with Collision?

This isn't perfect but does improve the behaviour somewhat. I believe there are some limitations to the Soft Body simulation that make it very difficult to get consistent behaviour in your situation (where soft bodies are being 'hit' at relatively high speed by solid collision meshes). There also appear to be issues with baking the simulation - if the 'bake' is attempted while the timeline is at Frame 1 then performance seems to be fine. However, if the timeline is part way through the animation then the bake takes orders of magnitude longer to complete.... I suspect this is a bug but will need to do more work to pin this down. Anyway, regardless of that...

There are a few things you can do to improve your simulation.

For starters, you should always run your simulation with objects which have had their scale applied (so their scale is 1.0,1.0,1.0). The reason for this is that the simulation will assume they are at their natural scale and any physical properties will be base on that scale. In your scene the 'pins' have been scaled - but there are also keyframes on the scale to set it back again. Therefore, select each 'pin' in turn and remove the keyframes on the Scale properties. Once done, select them all and Ctrl+A and Apply Scale.

Once you have applied the scale you can adjust your collision properties to set each of the 'pins' Soft Body 'Inner' zone to 0.35 (from the default of 0.2). This value is chosen to be around half the minimum size of the pin - so that the collision zones are as large as they can be without opposing faces' zones overlapping. This should result in more chance of the soft body vertices being repelled in the correct direction.

Since the collision objects are moving quite fast into the soft body meshes, the 'choke' Soft Body Solver setting could be resulting in the soft body being prevented from being repelled away from the collision mesh as fast as it otherwise would - it usually prevents intersecting objects from being flung away too fast but in this case we want to maximize the repulsion force, so reduce them to zero on each of the soft body meshes.

Freeing all baked dynamics and then re-baking them all (after first rewinding the timeline to the start) should now produce better results - although it's still not perfect.

The next stage would normally be to increase the Step sizes so that smaller steps are used when calculating the simulation and reduce the Error Limit. This does seem to help to a point but beyond certain values the collision appears to get worse again - as far as I can tell there is a bug in the soft body calculation with very large number of steps, to the point where using a very large number (eg, 30000) results in very odd results where the soft bodies appear to be sometimes repelled and at others completely ignore the pins moving through them. I'll attempt to pin this down further and, perhaps, report this as a bug if I can.

Anyway, I hope this gives you some pointers. My best simularion was using about 100 soft body steps (100 for Min and for Max) and reducing the Error Limit to 0.01. This produced the following result :

One further point I noticed is that your scene is at a rather non-realistic scale - the balls are around 2BU in diameter which equates to 2 metres in the 'real' world. I don't know if this is intentional. This means that the 'pins' are about 0.75 metres thick and are travelling at around 12 metres per second! It's hard to imagine how a 75cm thick bar hitting a 2m soft ball at nearly 30mph would behave but it probably wouldn't be pretty!

To get more of an idea of a more realistic scale I scaled the scene down so that the balls are a more reasonable scale and produced the following :


How to create a Cycles material with python to bake a curvature map

zero025 helped me to code it:

import bpy

#Generate the textures and shader
#################################
#Get texture in data-block
###########################
tex = bpy.data.images.get("curvature")

#If exist or not
#################
if  tex is None:
    #create texture in data block
    tex = bpy.data.images.new("curvature", width=size[0], height=size[1], alpha = True)

    #Create material nodes "CURVATURE"
    ################################################################

    # Test if material exists
    # If it does not exist, create it:
    mat = bpy.data.materials.get("CURVATURE")

    if  mat is None:
       mat = bpy.data.materials.new("CURVATURE")

       # Enable 'Use nodes':
       mat.use_nodes = True
       nt = mat.node_tree
       nodes = nt.nodes
       links = nt.links

       # clear
       while(nodes): nodes.remove(nodes[0])

       d_geometry  = nodes.new("ShaderNodeNewGeometry")
       d_colorramp = nodes.new("ShaderNodeValToRGB")
       d_emission = nodes.new("ShaderNodeEmission")
       d_output   = nodes.new("ShaderNodeOutputMaterial")
       d_image   = nodes.new("ShaderNodeTexImage")

       d_geometry.location = (-100,-100)
       d_colorramp.location = (200,-100)
       d_emission.location = (500,-100)
       d_output.location = (700,-100)
       d_image.location = (300,300)

       d_image.image = tex
       d_colorramp.color_ramp.elements[0].position = 0.4
       d_colorramp.color_ramp.elements[1].position = 0.6

       links.new( d_output.inputs['Surface'], d_emission.outputs['Emission'])
       links.new( d_emission.inputs['Color'], d_colorramp.outputs['Color'])
       links.new( d_colorramp.inputs['Fac'], d_geometry.outputs['Pointiness'])

#BAKING
#########################

#Curvature map

#remove every material slot of the high poly
bpy.ops.object.select_all(action = 'DESELECT')

bpy.ops.object.select_pattern(pattern="tmpHP")
bpy.context.scene.objects.active = bpy.data.objects["tmpHP"]

for ob in bpy.context.selected_editable_objects:
    ob.active_material_index = 0
    for i in range(len(ob.material_slots)):
        bpy.ops.object.material_slot_remove({'object': ob})

bpy.ops.object.select_pattern(pattern="tmpLP")
bpy.context.scene.objects.active = bpy.data.objects["tmpLP"]

print("\n> Baking: curvature map\n")

bpy.data.objects['tmpHP'].active_material = bpy.data.materials['CURVATURE']
bpy.data.objects['tmpLP'].active_material = bpy.data.materials['CURVATURE']
bpy.ops.object.bake(type="EMIT", use_selected_to_active = True, use_cage = True, cage_extrusion = cage_size, margin = edge_padding, use_clear = True)


Rendered environment map is misaligned to World

To transform an environment texture you'll want to manipulate the Generated coordinates:


Remove Console visualization on Blender Game Closing

I'm fairly certain that it has to deal with the fact that the console has to open up the extension files (eg. the .dll files) that actually make the game run. Reason being is that "most" systems will not have the accurate extension files. So, BGE adds the necessary files along with the executable to ensure proper functioning. As far as I know there is no way to "turn them off" because it is a necessary OS function. Hope this helps with your question.


How do I add a rigidbody to an object with python?

This will add rigid body to the object (add the object to the rigid body group of the scene)

C.scene.rigidbody_world.group.objects.link(C.object)

as zeffii pointed this assumes that a rigid_body_world has been created, which is done with bpy.ops.rigidbody.world_add()


Disappearing bone shapes with rigify (show_wire)

You don't need a script, simply hold Alt when clicking the checkbox, it should do the action on the whole selection. Unless this function is broken in your 2.8 build of course x)


Using Cycles Render, how do I produce a material with a transparent section of the texture?

Make sure you are using mixing transparent node with your material. And that the Transparent node is in the top input of the mix shader.

The Blend file I attached is the file the screenshot is from.


Mirror an object feet away from parent object instead right next to it?

In object mode choose your wall and go into edit mode. Select the front face of your wall and then shifts. Choose Cursor to selected. It will place the 3D cursor at the centre of the face (the front of your wall).

Go back into Object mode and select your door (the pink cube in my case). Right click and select Set Origin > Origin to 3D cursor.

The pivot point of the cube will move to the centre of your wall (front face).

Add a mirror modifier to the cube and set the axis (in my case the Y)

The mirrored cube will mirror across the pivot point.

For your walls if they are planes (single faces) then make sure your normals are facing the interior of the room and turn off backface culling. This means you can work inside your room without the faces (walls getting in the way).


How can I make two objects look like one?

You can use the Bevel node that you can find under Input category in the nodes Add menu.

This will however require joining the objects, but it will give you a bit more control than booleans. If you need to move the objects, you can use Hooks:

If you run into other issues in your workflow because the objects are combined they might be possible to solve too.


if i moved a separated object the whole object are moved..why?

Make sure you didn't accidentally activated the Proportional Editing Tool :

The shortcut is O.


When I animate, I get 10 different actions?

If you want to merge (append) the actions into a single action you could select the keyframes in the action editor to copy and paste Ctrl-C / CtrlV them. Both are also accesible from the Key-Menu:

In case you want to cross-fade them you would need to use the NLA-Editor and arrange the actions on its timeline.


The typical node arrangement looks like this. Remember to choose non-color for your metallic, roughness, normal, and displacement images. Also, remember all meshes must be UV unwrapped in order to display the materials properly.


After you duplicate and place your object, try invalidating the rigid body cache.

One way to do that is by entering and exiting edit mode and jumping to the start frame (ShiftLeft). You'll notice the colored bar along the bar along the bottom of the timeline changes color, which indicates the cache is no longer valid.


Here is another way using beveled curves:

Add a Bezier Circle in Object Mode and press Tab to enter Edit Mode.
With all handles selected press V and select Free.
Select only one handle and press AltC to open the circle.
Press ShiftS and choose Cursor to Selected.
Select the handle on the other side of the opening and press E to extrude and Enter to confirm.
Press ShiftS, and choose Selection to Cursor (Offset) to move the handle to the other side.
Rotate the handle by 90 or 270 degress to get a circular shape (R $Axis $Degress), then leave Edit Mode.
Add a Path in Object Mode. To get a closed slice, scale the Path by .5. Otherwise, < .5.
Select the Bezier Circle again. Under Curve Properties - Geometry - Bevel Object select the name of the newly added Path (e.g. NurbsPath).
To animate the slice use the Start and End values (Geometry - Bevel Factor).

This should be the result (animated scale of the Path, Start and End values of the Bevel Factor):

Another way could be using the Array Modifier together with the Curve Modifier to get some line effects (similar to the reference you provided).

Starting from a Bezier Circle and a Plane in the same spot, add both modifiers to the Plane. You can play with the scale of the Plane, count and offset of the Array Modifier to get different effects.

Here some examples:


The problem is that you removed the armature modifier on your mesh.

The armbands don't follow the armature because you haven't set a vertex group on them yet.


Unable to pose rigged hose or keyframe it

Unfortunately, bezier curve control points themselves are not keyframe-able.  You can, however, make a "hook" to those control points by selecting them in edit mode and pressing ctrl+h.  The hooks created this way are keyframe-able, and should give you the level of control you are looking for.


Calculate surface by logarithmic function?

math.log(x)

Yes you can use the log method in the XYZ surface, just have to remember that log(x) will throw a math domain error for any value of x less than or equal to zero.

Bad Example using helper method a = log(u) if u < 0 else 0 the equations are x(u, v) = u, y(u, v) = a, z(u, v) = 1

Unfortunately the minima of u and v can not be set greater than zero.  To set a range for say u to [1, 2] could set up a helper method b = u + 1 and use b for u. Similarly for v


That's the intended behaviour. Right click menu is for special actions based on the type of object you have selected, not for adding new objects.

To add an object, ensure you are in Object Mode, then either

use ShiftA
or left click on the *Add" button at the top of the Viewport


Can models with experimental features be exported?

Adaptive subdivision and micropolygon displacement are only processed at render time. They can't be exported in FBX. If you really want all that geometry, you have to use regular subdivision and a regular displacement modifier. However the level of detail used in Andrew's tutorial is unusable for a game engine. You should use the old method shown at the very begining of the video that is create 3 circles, add a screw modifier, an array and a curve modifier like this :

and add a normal map to get the details.


Rendering with direct lighting takes too long

For direct lighting in Cycles, you need to set bounces to 0, not 1, as done by the Direct Light preset. There is a bounce of indirect light in your render.

If you want to get performance closer to Blender Internal direct lighting, you can switch to branched path tracing, lower AA samples to e.g. 8, and increase the samples on the individual lights and world as needed to reduce noise.


The border around the colour swatch indicates that it is keyframed, which is causing the colour to go back to it's animated setting. The border on the colour swatch is equivalent to the green and yellow backgrounds of keyframed numeric values.

Right click  on the colour and choose "Clear Keyframes" to remove all of the animated data. The border will then disappear and your colour selection will stay.

If you only want the colour to change at a certain part of your animation, then you need to add keyframes to make the colour change when you want it to.


How to drag select through all geometries, not just visible geometry

It works the same way in current versions.
Just toggle the X-Ray button and you can select all faces/vertices under the cursor.


How to make such a strange file has no active object?

How to make the scene without any active object.

Since the issue is solved, I will explain by myself.
Consider the case where are two objects "Cube" and "Cone" exist.
"Cube" is selected and on the first layer. But the layer is turned off. On the other hand, "Cone" is active and on the second layer turnd on.
When "Cone" is deleted, active object will be None. However, "cube" is still selected.
If you turn on the second layer, the scene is completed.


Type coordinates for an object and move all other selected objects accordingly

Select all of your object while holding Shift. Make sure you select the object you want at the center last.

While all the objects are selected, press Ctrl + P and select "Object".

Now when you move the object that the others are parented to, the rest will move along with it.

Make sure your 3d cursor is in the center by pressing Shift + S, and then selecting "Cursor to center."

Now, select the object you want at the center, press Shift + S, and select object to Selection to Cursor."


In Edit mode you need to select at least one face or one edge of your object, or the whole mesh, meaning you want to cut this face/edge/whole mesh. Then activate the Bisect tool. On the bottom of the Tools panel (on the left of the 3D View) you can enable some options. I guess the best is to leave everything as it is. Then to separate the two parts you've created, keep the cutting selected, then press V to rip, now you can select a half or the other with L. To make another object with one of your halves, select it and press P > Selection.


@Tyler, Welcome!

Btw, your picture is showing your 2.76 Blender version (in the error log), but you are not saying much about which simulation, if you built it, or if you get it from friends, websites... it could be a buggy file, a buggy simulation, or not compatible, somehow, with your blender version (eg: it could be a very old file)... it could  be pretty much anything... help others help you giving some more info about how and where this is happening...

Anyway (again from the error log) it seems to use a "cellblender" addon, though. Did you have that addon installed? It's not in Blender by default... but if it's there it could be a different version from what your simulation expects (maybe an oldaddon version), or it has some bug...

I guess it is this:https://github.com/mcellteam/cellblender (related to http://mcell.org/): "CellBlender is an addon for Blender (2.6x-2.7x) to create computational cell biology models for use in MCell and potentially other cell simulation biophysics engines"

It could be needed to update the addon, or your Blender version, too. Version 2.78 is the latest in the 2.7x series.

edit:
I just installed mcell and cellblender, using latest blender 2.78 on my Windows 7 desktop pc, and then followed the "first time running" steps

http://www.mcell.psc.edu/tutorials/first_time.html

after which I ran this very basic tutorial, http://www.mcell.psc.edu/tutorials/single_molecule_diffusion.html

and it seems to work:

Maybe you can download and install a fresh new Blender .zip file (so you can keep the one you have installed), and double check to follow all required steps...

If this can help, here is the .blend file that I used to get those torus above:


According to Imgtec, the problem is not all meshes are triangulated. This python script fixes that.

Full discussion here.


Hair particles are not fitting my fractal ground

Set Random velocity to 0

As state by the Blender manual's page about the option:

  Gives the starting speed a random variation

Each object, having a different emission speed, is found at a different distance from the surface at the current frame (even if it is the staring one).


How to merge 2 parts of the same object?

Recorded a quick video showing how to easily do it.

The steps are:

Create two loop-cuts on the smallest/thinnest part.
Snap the new loops along the X axis(or whatever axis are appropriate for your mesh) to the mesh you want to merge it with.
Select the faces your mesh is going through and create an inset face.
Scale down the new faces and snap the edges into the thin piece.
When all edges/vertices are overlapping use Alt+M and select "By Distance" to merge overlapping vertices.
Finish off by either manually selecting and deleting the interior faces or use Select - Select all by trait - Interior faces to select them and delete


Does Blender offer network rendering on a LAN

There is no accepted, included, out-of-the-box way right now.  It's on the roadmap of features for them to add, but they haven't reached that feature yet.

Not to say you can't do it, though.  It will just involve custom scripts, python scripts, and some fiddling around to get it going.  Google "Blender network rendering", "Blender distributed rendering", and "Blender render farm" for some ideas.  Without more details about your situation, I can't really recommend anything more specific.


How can I sepearate objects into individual files?

If the purpose of your question is to manage your items separately I would recommend making groups - which is done by selecting the objects and CTRL G. The advantage of this is you can choose to have one file with them both linked in, and the other two groups appended into separate blend files. This gives you the freedom to work on them separately and then just update the mother files...as it were.


Unselected vertices and edges move along wth selected ones

Most likely you've turned on proportional editing.

To turn it off press the O key.

Or use the proportional editing icon on the bottom of the screen:

Follow this link for more information on proportional editing


Can a Mesh Deform modifier be successfully used with a fluid simulation?

No - a fluid mesh cannot be used directly as the deformation object in a Mesh Deform modifier, nor can it be deformed by a Mesh Deform modifier.

The reason for this is that the Mesh Deform uses the change in the mesh of the 'Object' to affect the target mesh by reacting to the changing location of each individual vertex by 'binding' vertices together - by determining how much a vertex in the 'target' mesh would be affected by the position in the 'source' mesh and averaging those deformations over all vertices. For this to work there must be a fixed number of vertices in each mesh (the source and the target). In a fluid simulation, the mesh is not actually deforming from frame to frame but is being effectively re-built for each frame to represent the fluid in that frame. Since the fluid mesh is effectively rebuilt each frame it is not actually the same vertex that represents a particular part of the fluid throughout the animation - and this breaks the deformation.

That said, if your requirement was to deform an object within a fluid as that fluid moves, there is a solution by using another mesh to deform based on the fluid and use that as the Deform Modifier source.

First, create your fluid simulation :

Add another mesh with sufficient geometry to capture the motion of the fluid - eg, a subdivided Cube. Make sure you add enough subdivision to capture the required detail of the fluid (you'll probably want more detail than I've added in my example images - I purposefully didn't subdivide too far so as to be able to clearly show the mesh deforming). Add a Shrinkwrap modifier set to shrinkwrap to the fluid - the 'Project' mode of the shrinkwrap is useful here so that vertices can project up to the surface :

You should now have your "shrinkwrapped" mesh deforming to the fluid :

You can now use this as the source of deformation :

This can produce the following result :

The other alternative is if you want to deform the result of the fluid simulation base on another mesh (which is your actual requirement), and this cannot be done with the Mesh Deform modifier due to the changing vertices throughout the animation (due to how the mesh is completely rebuilt between frames).

However, this can be achieved with a Lattice Deform instead. A Lattice deformation is very similar to a Mesh Deform but is greatly simplified - instead of being based on the 'target' being within the 'source' mesh (and so the effect of each vertex is applied to each vertex in the target), it is the actual deformation of the whole lattice that affects the whole of the target mesh (regardless of whether it is within the source mesh or not). You could potentially also apply a Mesh Deform to your Lattice so that the mesh deform affects the lattice and the lattice affects your fluid simulation.

If you could update your question to include more specific examples of what you're trying to achieve I could include more specific details of how this could be applied to your case.


is it possible to make an animation / render of just the glossy passes?

Here how to in Cycles:

First, enable Glossy passes in Render Layers:

Next open node editor in Compositing mode and click Use nodes

Here is the glossy passes, all of them are important.

To make glossy pass you should combine this 3 passes in specific way.
Add 2 Color mix nodes (Shift+A -> Color -> Mix) Change one of them to Add, second to Multiply. Gloss Direct will add to Gloss Indirect, then this sum will multiply by Gloss Color (Connect nodes in this way):

So, in this point you can start to render


Connecting body parts or clothes problem

you could parent them. I would add an empty and place it in the center of the object. Then select all the parts of the object and clothes, select the empty last. Then ctrl + P --> object. If you select the empty and move it, the rest will follow.


Updated: Cycles show missing Texture (magenta)... until i reconnect the materialnodes

Found a solution! Converted the 16-bit png-files into 8-bit png-files. With these the problem doesnt seem to appear. But i'm still curious... perhaps someone has an idea why that happens with the 16bit Textures.

I'll have a look at the bugtracker... to see if it's been reported. If not i'll post that in there. (Thanks Matt!)


Apply Scale to your mesh first in object mode.

Ctrl+A >> Scale.

Now try Inset faces again with I.


Why do objects in front and back view look reversed?

Front in Blender is considered to be Y axis, when the camera is facing towards positive Y you see the side of an object facing negative Y direction. This doesn't have to make any sense, it is not supposed to as there is no one logical reason to have it any one particular way.
You can use the shortcuts Numpad 1, Numpad 3 and Numpad 7 to quickly switch the viewport to front, side, or top views, you can also hold Ctrl to reverse the direction when using these hotkeys, Numpad 2,Numpad 4, Numpad 6 and Numpad 8 rotate the view, holding Ctrl with these 4 will pan it and Numpad 9 reverses to the other side.
You can also use the gizmo at the top right corner for this:

See the documentation for more info
That should really cover all your precise navigation needs whatever side you need to view.
And I just realized, you might be talking about inverted normals...
Would it hurt to post a picture to help me avoid wasting my time when trying to help?.. Anyway, if you are seeing something like this:

Go to edit mode(Tab), select all(a), open normals menu(Alt+n) and choose flip normals(f):


Why is some code being skipped in the BGE?

After some time i now found the solution.
The problem was that this code was executed in a Try execept function. thats why i got no error (my bad). But the actual problem was that the object i was looking for wasn't in the list. this is caused beacause the object was parented to an object on an active layer but the object itself was on an inactive layer. I searched in both lists (scene.objectsInactive and scene.objects) but the object wasn't in any of them.

fazit: you shouldn't parent objects on different layer when one of those layer is Inactive.


Bump map not showing differences for different height

I'm not sure the Z depth value is helpful here.
I used this Robin Betts' answer for the height map instead

Render the height map
Set Bump Distance to correspond to your object's max height (0,5 m in my example)
Done

Geometry with 0,5 meters max height

Generated Height map

Bump Distance with 0,5 m height


Here is a step by step calculation using vectors:

import bpy

obj = bpy.context.object

edge = obj.data.edges[0] #An edge, the first one

vIndex1 = edge.vertices[0] #Get the indices of the vertices of this edge
vIndex2 = edge.vertices[1]

v1 = obj.data.vertices[vIndex1] #Get the corresponding vertices
v2 = obj.data.vertices[vIndex2]

vCoord1 = v1.co #Get their coordinates
vCoord2 = v2.co

edgeVector = vCoord2 - vCoord1 #The vector formed by these two vertices

edgeVector.normalize() #So that it has 1 unit length

distance = 0.5 #Say we want to move v2 of this distance of 0.5 units

v2.co += edgeVector * distance #Translate the vertex

You can summarize by:

v2.co += (v2.co - v1.co).normalized() * distance #Translate the vertex


This is a common issue, it's called "Fireflies" by the community and there are a lot of ways of dealing with them.

Here's one good article, but before you dive into it let's discuss where they come from in the first place.

Cycles is a PathTracer. For each pixel it sends out a bunch of light rays from the camera, bounces them around and then sees where they end up to determine the color of the pixel. This works because physics doesn't really care if times is going forwards of backwards in this case.

You can determine how often a light ray bounces around by adjusting the "Samples" option in the render tab. Try 100, 200, 300 and so on - more samples means more calculations means more render time, but also less fireflies and noise in the image.

An alternative to that is the "Denoiser", which you can find in the "Render Layers" tab on the right. It's a tradoff between quality and performance, give it a shot if your render times are too long.


How to control the angle and range of a light

If you want to keep it in cycles, you'd better model your own lamp as anything can cast light. This way you can control the shape and with a light falloff node you can control the distance.

assign the correct shader : emission for the face you want to cast light, plastic or anything else for the other parts.


Can't combine render layers when compositing

Nodes inputs have this behaviour: the upper input is considered as the "background", the lower is overimposed as much as the fac slider goes toward 1.0, with the choosen blending mode (in your case: screen).

In your nodes setup the first mix (screen) node has the fac set to 0.0, meaning that the lower input (blur 5 and 5) is excluded, you only have the "35 and 35" working.

Iin the second mix (screen) node you should switch the two inputs.

In Blender generally we use a different way to manage the layers than Photoshop or others image editors:
you could render the "background" scene with transparent sky, set the sun scene as background (upper input of a mix RGB node, set to "mix"), normal scene on the lower input, use the alpha value of the normal scene as FACtor, so that the only part of sun scene is visible only on the transparent portions of the normal scene.

The image  in the fac input (alpha of the normal scene) means: black = show upper input only, white = show lower input completely mixed with upper according to the choosen blending mode, greyscale inbetween.

To inspect the images of the various outputs of the nodes: Ctrl click them more than one time: they will show their various values in a circular mode.

If you understand this general behaviour you will be able then to let the sunlight "bleed" on the normal scene.


How to import a pose from a different file?

You have to parent the armature to the mesh, select the mesh, and then select the object, and then do crtl+p and then parent with automatic weights.


Reflections of the environment at infinity are extremely sensitive to the interpolation of normals across faces, which are calculated from the vertex, (or per-face vertex,) normals at the corners of triangulated faces at render-time.
So one thing you can do to adjust the regions of the environment which are reflected, and therefore the 'focus' of the reflections, is to introduce, and/or adjust bevels on loops surrounding relatively large faces, as on the right, below.

You had some changes of angle without bevels in your model; I put a couple of 2-segment bevels in there, and adjusted their profile with overlays switched off. so I could see what was up without wireframe in the way. I also replaced your other bevels, to adjust their widths and profiles.
My result. of course, may not be exactly the one you want, but if you go ahead and do the same with your copy, you'll see how dramatic the effects can be.


There are mainly four steps you should take, when following your approach with emissive materials in Eevee:

In the Color Management panel, set the View Transform to Raw (if you're not saving as OpenEXR)
Use the RGB slider to set the color values or be aware of gamma correction
Be aware of floating point inaccuracies or use OpenEXR as file format with Float(Full)
Disable anti-aliasing

The first point ensures that the exact scene referred values are stored without mapping them to different values through the view transform. The filmic view transform would be useful for realism when rendering a scene, but not for non-color data such as masks.

The second point ensures that you don't get confused with the gamma correction. By setting it through the RGB slider, you're directly entering the values used in the scene without gamma correction as explained in the manual. The output will therefore contain these exact values when using the raw view transform as long as the image format can represent them. You can use the hex values, but be aware that they are interpreted as gamma corrected. This is common practice, but I've seen people get confused by this.

  In Blender, the Hex and HSV/HSL values are automatically gamma
  corrected however, for the RGB values, they are in Scene Linear color
  space, and are therefore not gamma corrected. For more information,
  see the Color Management and Exposure page.

The third point ensures that the selected color value can be accurately represented in the image format and is exactly the floating point value you chose in the color picker. If you use OpenEXR, you don't have to set the View Transform to Raw because it already stores the raw values. Of course you can choose a different image format, but it may not be able to represent the color accurately because of lower floating point precision or because it uses the [0-255] range per color channel.

The last point ensures that only the exact colors appear in the image an no blending between colors happens in adjacent areas. When using Eevee set the Filter Size in the Film panel to zero, for Cycles select Box Filter.

There are other options to accomplish the same task in the compositor. For instance if you'd be using Cycles, the Cryptomatte would give you masks for objects or materials.


You simply have to tell the Viewport to actually display textures/materials. Currently it's rendering "solid" which is often the best option to model (Some prefer MatCap)

To solve this, select Texture or Material in the highlighted dropdown:


Modeling objects using polar coordinates rather than cartesian coordinates?

This looks like a job for Custom Orientations. ('+' in the Orientation dropdown, after making a defining selection)

To flatten to a defined plane, select 3 vertices which define the plane, (or more, for an averaged normal), create a Custom Orientation from them, and with a suitable pivot point, SZ0. I usually set the pivot to 'Active Element', and make a vertex I want to lie in the plane active.
To translate elements in a defined direction, select 2 vertices which define the direction, and create a Custom Orientation from them. Then it's GY (optional numerical entry) on selected elements.
To straighten vertices to a line, select 2 vertices which define the line, and again, with a suitable pivot, it's SShiftY0

etc, etc.

If you do this a lot, it's probably worth creating a keyboard shortcut for the addition of a Custom Orientation, and maybe setting that operator to 'Overwrite Previous', and/or 'Use after Creation'.


Blender is a 3d creation tool. It already has everything you need to make any kind of graphics or architectural visualisations including 3d floor plans like this.

If you wish to work with 2d drawings, Blender can produce lines that can be exported as vector formats including dxf, it is also possible to import vector drawings to Blender and there are many modelling functions in Blender that can be used to work with 2d lines(curves or mesh edges). However it is not designed for this kind of work specifically and for this task you may want to use specially designed software because that might be easier. Special 2d CAD drawing software like ArchiCAD or Revit usually has templates, pre-made libraries of standard symbols, ways to print the drawings or save them to PDF and other useful functionality. It is possible to achieve that in Blender, however it will take a lot longer and will most likely be a lot more work if you only need 2d drawings.

There are some add-ons that aim to provide some functionality related to this. You might want to check Blender-Archipack out and search for more add-ons realated to architecture.

As for plans to make Blender into something that could be used for 2d architectural drawings specifically and would have all the expected functionality of 2d CAD software packages there does not seem to be any at Blender Foundation which is the main organisation developing Blender and it is probably unlikely there will ever be such plans as Blender is designed as specifically 3d creation tool and that is very unlikely to change. It is open source however, so there is nothing stopping anyone to take on such a task and make whatever they want from Blender, however there does not seem to be any serious projects like that at the moment.


This is possible in EEVEE and Cycles without compositing by using the Light Path Node>is Camera Ray output.
A node setup like below will allow you to do just what you are asking:

This produces the following result in the EEVEE viewport:

Notice that the background rotates, but the lighting does not.


Array with more than one empty is it possible?

Array + Curve Radius is the way; you just need to use duplifaces with the scale option instead of arraying the final object directly.

Setup a simple plane object and use the array as desired on it. This plane will only be used as "emitter" for the true geometry you wan to to array.

The array on its own will guarantee constant spacing. Then add a Curve Modifier and adjust the curve radius as you already described.

This will distort the plane, but not any duplis it may have, so now parent your true array geometry to said plane object with the array.

In the Properties Window > Object > Duplication turn on Faces, and tick the Scale option.


Bump Map Painting - Low Resolution (Cycles)

I've had this issue too, I think its caus when creating the image theres a option for 16 bit / 32 bit image and you should use that rather.

And change the image nodes Linear to > Smart.


Most efficient way to repeat a cutout pattern

One way to do this is with a radial Array Modifier (read about it here: How to make a circular array using offset object as center? ) and a Boolean Modifier or the Booltool add-on.
first, for convenience, put your round cylinder thing right in the middle of your scene.

Then put a little cylinder, the size of one of the little holes, on the edge of your big cylinder (make sure it sticks al the way though). In exactly the same spot, put an Empty (can be any Empty or Object). In the image I used a Plain Axes.

Now put an Array Modifier on the little cylinder. Put in the right a number of cylinders in the Count field (just put 100 first and adjust it later).
Uncheck all the Offset boxes, but check the Object Offset box. As a target, choose the empty.
Then make sure the Transform Pivot Point (here at the bottom of the image) is set to 3D Cursor. Press Shift + C to put the 3D cursor in the middle of your scene, and because you put the big cylinder there, in the middle of the big cylinder.
Then rotate the empty on the z-axis. (I think you will need only a fraction of a degree)

Then duplicate your tiny cylinder and go into Edit Mode. Move it a little bit down and a little bit to the side (to get your alternating circle cutout pattern).

Activate the Booltool add-on in the Preferences window.
Select the cylinder array, and then shift select the big cylinder. With both objects selected, choose Difference.

Then hide or delete the cylinder array.
Result with three arrays:

If you want less holes, apply the Array Modifier, and delete the holes you don't want before using Booltool
You can also apply the Array Modifier to two rows of tiny cylinders, make them one object by selecting them both and pressing Ctrl + J. And then put another new Array Modifier on the new combined object with a Constant Offset or Relative Offset in the z-axis direction. And then do the Booltool actions.


object parented to bone does not stick to its place

Your rig uses weight paint for moving the body parts, whereas your glasses are curves with empty parent, which is parented to the bone - head.
Rotating bones causes them to affect the body with the weight used from weight paint, and the decorations are just parented to them, so body is deformed with weight (more or less), and decorations are just copying full rotation from it's parent.

So, when you rotate head you are affeting the neck as well, so weights are applied. However, your accesories use only head bone transform info.


FBX Importer AssertionError (unknown location -1) when importing .fbx from wow model viewer

That kind of issue must be reported to our tracker, with an .fbx example file to reproduce it…


The long and short of it is that the values for lights in cycles don't directly correspond to values you'd use in everyday life.  Sun lamps are expressed in irradiance, for example.  Things in blender also have default values that are often set to meet the needs/expectations of the greatest number of people and may not necessarily be what you need.
You can read a little more in the documentation.


I assume the normals are correct and there is no hole in the mesh since its from the web.
Delete the vertex groups on the mesh and try scaling it up, the automatic weighting works better when the faces are more spread out.


Mirror material works in blender but does not work in standalone game?

For some reason the obj["RenderToTexture"].refresh(True) makes it not work. If I change it to obj["RenderToTexture"].refresh(False) it works also in standalone for me. Strange...


The second line with "X Y Z" of the "direction to rotation" node is to indicate which axis of the object is to keep to the direction indicated in the "guide" vector in the bottom part of the node.

Here we have Z=1 (up) as guide so using Y will align to Z.

A complement: using this guide you can also plug the target's rotation as guide. This will give the following effect (note that AN is clever enough to automatically convert the rotation as a direction, adding another "rotation to direction" node):


Same class name is not an issue.
when a register-able class is registered it is added to bpy.types with a name generated from the bl_idname.
eg
class Foo(bpy.types.Operator):
    bl_idname = "object.test"

if succesfully registered will be known to blender as the class
bpy.types.OBJECT_OT_test

or similarly after running question code in text editor (__main__ thread)  The OT stands for "Operator Type", similarly PT and MT are Panels and Menus respectively.
>>> bpy.types.OBJECT_OT_test
<class '__main__.OBJECT_OT_CustomOp'>

>>> bpy.ops.object.test.idname()
'OBJECT_OT_test'

>>> bpy.ops.object.test.idname_py()
'object.test'

Can also import it as a module from text block, and run the register method. This is, IMO, a better way to test simple addon code in blender as it gives the option to unregister, since the classes are no longer "lost" in the main thread.  Find Link
>>> myaddon = D.texts['Text'].as_module()
>>> myaddon.register()
>>> bpy.types.OBJECT_OT_test
<class 'Text.OBJECT_OT_CustomOp'>

So has now re-registered the operator, this time belonging to the "Text" module.
Having a variable the same name in the scope of its own  module is no issue.  Having another matching bl_idname will overwrite the one registered previously.
Would either stick to naming convention and
class OBJECT_OT_test(...):
    bl_idname = "object.test"

or not at all
class TestOperator(...):
    bl_idname = "object.test"

whereas feel question's OBJECT_OT_CustomOp is some hickly-dy pickle-dy in-between sort or arrangement.


Select your domain. Go to the particle properties tab. Change "Render As" to "None"


If your video sequence has transparency such a png, then the video sequence editor VSE, can layer the video with alpha transparency setting.
There is always the simple fade to black and start over with alpha transparency.
The particles themselves can fade to black in a more random fashion with the particle info node.


Use some transparent object and make the boolean difference with the door.

Modifier setup on right below:

Alternatively, if for instance the boolean fails, you can modify the door material so that everything above an empty is set transparent:

The node setting compares the empty position (object texture coordinates, so one location) to the correspondant location on the object surface (also one location). If the Z part of these locations are showing that the door is upper the empty, alpha is set to zero.


Use Blender Python Libraries Outside Blender

mathutils available as pip module, use
pip install mathutils


Movement/rotation etc. hypersensitive in perspective view but normal in orthographics

Create 2 3D View windows.  Creating many windows in Blender is Easy.

One in Orthogonal View.
Perspective View

Perform the operation in Orthogonal,  while viewing in Perspective.  Also start your change with the mouse reasonably far away from the item in question to dampen the operation.  For example for small angles start with the mouse far away from the object.
Also other tools exist beyond Grab.  Try the Snap operation.


Actually you can animate mask in two ways:

By Inserting shape key for selected mask points:

By parenting one or more mask points to a tracking marker in Clip Editor. First select one or more mask points, then hold Shift and select the marker, press Ctrl P:

VSE Mask modifier effect will be synced with the changes.


You should probably reinstall blender. The reason your screen goes black is probably because when blender "crashes" he starts to pull huge amounts of ram so keep your task manager open and before he eats more than let's say 80% you force close it. If the problem keeps happening I can't really help you much. It's probably some system error.


Is there any way to import a .json model into Blender?

Have you found this addon here? https://github.com/warmwaffles/io_mesh_json and here with https://www.barneyparker.com/blender-json-import-export-plugin/ comments


How to import 12-bit tif image sequence in Video Editor?

According to the Blender Manual, 12-bit TIFF is not supported (but 8 and 16 bit TIFF is): https://docs.blender.org/manual/en/dev/data_system/files/media/image_formats.html

I suggest converting the sequence to a different format (e.g. 16-bit TIFF, which is supported); there are several softwares that can achieve this. (I often use FFmpeg for this purpose—please let me know if you'd like help with FFmpeg.)


Cloud generator addon unable to create mesh?

The Convert button will only appear if you use the particle system to create duplicates of other objects or when creating hair. To create duplicate objects, under Render in the particle settings, change from Halo to either Object or Group (the latter can be used to duplicate several objects with a single particle system). In the image below, I've created 1000 duplicates of an icosphere.

To generate hair, change Type from Emitter to Hair in the particle settings. Since hair is probably not what you need here, I'm only mentioning it for completeness, and further explanation of it is a topic for a different question.


The scripting tab can be enabled under Settings->Plugins->7_scripting. When you restart MH, there should be a Scripting tab under Utilities. I have not yet run across any documentation, but the GUI does have some example API calls that you can append to your script by clicking the button. Good luck; I'm trying to figure out how to use it, too.


Something is wrong with "Link object data" in Blender 2.81

Set Origins First.

Speculate that the array objects are the result of applying array modifier and separate by loose parts.

Notice they all share the origin of bottom left corner original.

When you link data the non offset mesh of active is given to all objects of array, hence you have all objects in same location.

Simply set origin to geometry of array selection (eg in question GIF, after selecting all white spheres, and  before selecting red object and linking object data.


How to create a mesh imprint of one object onto another?

Select the ocean mesh
Apply a Decimate modifier (to the ocean mesh only) try a ratio of 0.2 to
start with.

Retry the Boolean modifier using the Difference option again.


Where is the Overlay dropdown in Blender 2.9? it appears to be gone from the viewport

The text "Overlays" has been removed but the button is still there. There is just a small down pointing arrow.


How to split an inset from another inset

if you hit "I" twice, it will inset individual faces. It's in the modal description:


Create the designs in photoshop or whatever image editing program you use. Export them with alpha.

In your material node, add a new image texture and mix it with your regular wood texture. Go to texture paint mode and load your art from photoshop as a texture for the brush. Set the brush mapping to Stencil and orient your view appropriately.

Here's a tutorial on how stenciling works in Blender: https://www.youtube.com/watch?v=VnfTSXWF21A


I could be wrong, but for view bound meshes, even though Blender doesn't render those polygon faces, they still render the vertices points for meshes, which is still a performance hazard. By the way, I totally forgot the wireframe modifier works at run-time for 0.3x. Does this solve your problem?


How can I switch between Move/Rotate/Scale with shortcuts without straight altering coordinates?

Blender lets you exclude one axis from transform actions.
Type the letter, X or Y or SZ to constrain after pressing the transform hotkey G, R, or S that you wish.
Or, type Shift + (letter corresponding to axis to exclude), G followed by X would move along the X-axis. G followed by Shift + X  would move along the Y and Z-axis.


In the material nodes, on you image texture change linear to closest. This should fix it. Then also try going into material view mode.


I've found the issue.

You need to disable autosmooth normals in Object Data.

Properties->Normals->Auto Smooth uncheck


Linked Objects, Drivers and Animation of custom Properties

It seems like this is not supported yet in blender. to bring in the same object multiple times you need to save the object again as another copy and import that separately...

people have answered this here:
multiple copys of character with rig linked in the same file


I'd say it's this bit

    dir = camera.location - pointer.location
    intersections = []

    for face in bm.faces:
        verts = []
        #print(face.index)
        for vert in face.verts:

            loc = obj.matrix_world * vert.co
            verts.append(loc)

        dir.negate()
        found = geometry.intersect_ray_tri(verts[0], verts[1], verts[2], dir, camera.location, True)
        intersections.append(found)

dir.negate() is being called for each face, effectively flipping the the ray on each iteration, giving a 50% chance of hitting the tri when it is in camera to pointer ray path.

Suggest setting

dir = (pointer.location - camera.location).normalized()

in the first place, and removing dir.negate().


Finally i got it now.

Every face have a direction, some faces had a wrong side, so i had to flip the faces.


I found the solution. It is a bug in Blender and it does not accept (0,0,0) as angular velocity. It should be a small number instead of 0 for example (0.00001, 0.00001, 0.00001)


Determine if a Python file is running in Blender?

edit: This answer will not work since Blender 2.91 because the meaning of sys.executable changed, see https://developer.blender.org/rB04c5471ceefb41c9e49bf7c86f07e9e7b8426bb3.

I found an example of this on the "Blender as a python module" wiki: https://github.com/TylerGubala/blenderpy/wiki/Caveat---Importing-Addons#development-of-new-gui-addons
Their suggestion is to test os.path.basename(sys.executable) for a prefix of "blender" vs "python", eg.
in_blender = os.path.basename(sys.executable or '').lower().startswith('blender')

(Testing sys.executable is a little better than sys.argv[0]. A script with a shebang line called like ./blender-script.py will have a sys.argv[0] of "./blender_script.py" (giving a false positive), while its sys.executable will still be the path to the python interpreter.)
Another idea is to test that sys.executable is the same as bpy.app.binary_path
try:
    import bpy
    in_blender = (sys.executable == bpy.app.binary_path)
except ModuleNotFoundError:
    in_blender = False


What causes this glitch in this mesh? How do I remove it?

I took a look at your file. First I tried switching to the smooth brush and putting the strength to 100 to try to smooth it out. It seemed to look better after but there was still something majorly wrong with it.

Then I checked it out in edit mode and noticed a naughty 5 sided NGON inside the mesh.

Ngons = bad bad bad. So I would fix that for a start. :)
Another thing I noticed while trying to give you a fixed version of the sculpt is that during your sculpting, you've managed to move the mesh off the centre of the grid, so now the sculpting is no longer symmetrical, so be casreful when moving your object and make sure the origin sits at 0.000 on the X axis at all times.

Now editing your sculpt in edit more when using the multi-resultion modifier can cause it to break your sculpt. (this is to do with the fact that all vertices are numbered and the multi-resolution modifier identifies the location of each individual vertex by it's assigned number). So if you delete a vertex and replace it, then the vertex numbering is all changed and it causes major problems with your sculpt.

The best way to solve this is to first:

1) Go into Object Mode >> change the location of your sculpt to 0.000 on the X axis.

2) Go into Edit mode >> Remove your ngons (faces with more than 4 polygons) and try to make all your faces into quads (four polygon faces). I saw the back of the leg was an ngon and the upper legs contain two ngons each so there at least 5 ngons you can try to make into quads :)

Then press W and "Remove Doubles". Also, press Ctrl+N to make sure all your normals are facing outwards (these two are just in case).

3) Unfortunately, now you'll need to delete your multi-resolution modifier in Object Mode.

4) Now press Ctrl+A and Set Rotation and Scale. (Again this is just in case).

5) Now you'll have to start sculpting again. Yes, it's a pain in the backside but think of it as practice and usually when i have to do a sculpt twice, the second time always turns out better!

Good luck and happy sculpting!


Ok guys, it wasnt that hard, just had to change about 4 parts in the code where I get the height of the area and do a simple height - y to get the y position (same for the mouse cursor)


DanPro (https://www.youtube.com/channel/UC4lLVkUGPtM5pnS3ZskvECg) answered my question with this post (https://blenderartists.org/forum/showthread.php?412404-Corrective-shape-key-driver-for-the-shoulder) and this tutorial (https://www.youtube.com/watch?v=wUs04SGUnVI).
Quote from DanPro in the BlenderArtists link:

The shoulder does not rotate on the Y axis for the standard Rigify Rig. It only rotates in X and Z and that is on the bones Local axes. I can't tell from the screenshot how you have the bone aligned so I cannot tell you which axis to use. (Turn on bone axes display.) You can find this out by using the hotkey R, then X,X, or R then Z,Z (if you are using Normal or Global Transformation Orientation). Change your variable to this other axis, once you determine which it is.
Also, change the bone to ORG-upper_arm.L instead of the FK bones. This way, whether you are using IK or FK controls to pose, the driver and corrective shape will still work. The ORG bones for legs and arms is the intermediate that switches between IK and FK, so this is the bone that should be used to drive corrective shapes. (In most cases. Exceptions always apply.)
One more tip, a human cannot raise their arm like in the screenshot unless they involve the shoulder. The shoulder needs to be raised whenever the arm reaches the T-pose position and above.

His rigging tutorials are the best I've found on YouTube.


Things have to be completely contained in the fluid domain in order to be considered/Calculated.  You may need to scale up the domain so it completely covers the scene and the obstacles.  Also, if your domain's scale is off, your particles may phase through things because of size differences.  Try scaling your scene up (to around 4 or 5 meters), but also know you will increase the cache size and simulation complexity.

I'll load this up later to make sure, but this looks a lot like my struggles with the fluid sim.


Add-on has a warning that "this script is RC". What does this mean?

RC means Release Candidate that is a final stage of beta version.

Software release life cycle

The warning is added by the Authors of the add-on in its bl_info dict, it does not come from Blender itself. Warnings like that are an attempt by the Authors to inform you (the user) about the add-on's state of completion


How do I get a python script to run after the .blend file loads from the command line?

Command line arguments are run in the order they are given. So at the minute, yes, the Python file is being run and then the 'test.blend' file is being opened.

To fix this you just need to put the blend file part of the command first and the Python file after:

blender test.blend -P test.py

Now your file is opened then the Python commands are run in that opened file.


Why do colours display differently in texture and solid view? (3D scan)

The bottom picture is possibly what the texture actually looks like, and the texture in the top is affected by the lights in the scene if it is not set to Shadeless in the material. Might want to look at the corresponding texture in the UV Image Editor and check for the green there.


Forcing Subdivide to create non-zig-zag edges

The problem is that you have a "triangle fan": A bunch of triangles converging on a single vertex (also known as a pole). The subsurf modifier will not work well with that.

You need quads.

Delete the vertex at the center of all the triangles.

Select the inner ring loop and press E to extrude and without moving the mouse press escape

Then scale all of the vertices to 0 (S0)

That will make all of the newly created vertices converge in a single place. And the subsurf should work well.


How to make an object automatically squish slightly at point of impact, while animating

What I did...

1 Created a UV Sphere
2 Created a 2X2X2 Lattice
3 Created an empty
4 Parent the UV Sphere and Lattice to the empty object.

Now ...

1 Create a vertex group selecting the bottom half of the sphere
2 Named the group "GroupSquish"
3 Fit the lattice and deform it's bases, leaving the top half lattices untouched.
4 Made sure the lattice only affect the "GroupSquish" vertices on the sphere.

Finally ...

Move the sphere up and down you should see the effect the lattice have on the bottom half of the sphere. Of cos I created this pretty quickly and you could
fine tune the effect further if needed.

So logically you can now animate the ball going up and down and it should just deform. And add horizontal/lateral(XY Plane) motion by animating the "empty" object! Voila!

Here is the blend file !!! How generous of me :)


You can use static custom properties for this;

import bpy

def foo(self, context):
    print("my test function", self)

bpy.types.Scene.testprop = bpy.props.FloatProperty(update=foo)

This will print:

my test function <bpy_struct, Scene("Scene")

When the property is updated, through:

 bpy.context.scene.testprop = 11.0

Note that the FloatProperty function takes the arguments:

FloatProperty(name="", description="", default="", maxlen=0, options={'ANIMATABLE'}, subtype='NONE', update=None, get=None, set=None)

Which are all optional; This does, however mean, that you can define set and get functions for the property.

You can also use StringProperty and BoolProperty

If you want to add it to the UI, in a custom location, use something like:

class myPanel(bpy.types.Panel):     # panel to display new property
    bl_space_type = "VIEW_3D"       # show up in: 3d-window
    bl_region_type = "UI"           # show up in: properties panel
    bl_label = "My Panel"           # name of the new panel

    def draw(self, context):
        self.layout.prop(bpy.types.Scene, "testprop") #Make sure this matches the name you gave to your property.

bpy.utils.register_class(myPanel)

It will be found under the Scene tab, in the Properties panel, otherwise.

The custom property is basically a field and can be read, programatically, as:

bpy.type.Scene.testprop

And delete them with:

bpy.ops.wm.properties_remove(data_path="scene", property="testprop")

You can check the relevant docs here, and the API here.


For a Third Person game, how would I go about making the character's arm follow the camera?

It really depends on how you are controlling your character and camera; there are many different methods (ie. camera actuator, edit object actuator -> mode: track to)

The way I would go about setting up controls like Just Cause 2 (shooting) is to add an empty for the location of the camera behind the character, and another empty (or object) for a reciticle and when holding down an "aiming" button move the camera to the location of the empty and "track to" the reciticle with both the camera and the arm/gun. And make the mouse control the reciticle.


How do I animate rotating 90 degrees, then rotate back to the original place?

You need to use basic keyframing.

Got to the start of your animation, it I>Rotation move ahead in your timeline, rotate it by 90o and I>Rotation. Move the the next location of the spin animation, and repeat the above steps.


I'm stupid. I forgot to add a material modifier.


Shaders are implementation specific, and there are no real standards as to how to process, store, or describe them.  Blender uses a variant of OSL for cycles, and a slightly different version for EEVEE.  Unity uses DirectX (HLSL) and OpenGL (OGLSL) shaders (based on the target platform), Unreal can do something similar.  Substance uses a proprietary format for their PBR shading.

Occasionally, if two tools are widely used, the parties involved will make a bridge between the two.  However, without knowing what you are trying to export to, we cannot give much advice.


When you add a torus, you have the Adjust Last Operation panel floating in the 3d view. It may be collapsed so just expand it.

The panel is only available after an operation and once you perform another operation it disapears.
These settings are specific to Add torus operation, other operations will have other kinds of settings in the same panel.


Just like Blender Sushi Guy demonstrated with nodes, the same math can be done with driver expressions.

Add a driver to the Constant offset off an array modifier.

Add a driver to the scale (or position) of the stripes.

Create an empty to control the stripes.

To have one less variable, I set the camera as orthographic with a width of 10.

no       number of bars
gap      size of gap between bars
width    width of bars
10       total width

Fixed gap size, varying stripe width

We need to set the width, and the position of the first stripe, based on the number of stripes and the gap size.

Size (X)

(no + 1) * gap + no * width = 10

width = (10 - (no + 1) * gap) / no

Constant Offset (X)

(We have to divide through the width, since the modifier bases its offset on the width.)

[(10 - gap) / no] / width = offset
[(10 - gap) / no] / [(10 - (no + 1) * gap) / no] = offset
[(10 - gap) / no] * [no / (10 - (no + 1) * gap)] = offset
(10 - gap) / (10 - (no + 1) * gap) = offset

Fixed stripe size, varying gap width

We need to set the gap size, and the position of the first stripe, based on the number of stripes and the width of the stripes.

Location (X)

(no + 1) * gap + no * width = 10

gap = (10 - (no * width)) / (no + 1)

Constant Offset (X)

[(10 - gap) / no] / width = offset
(10 - gap) / (no * width) = offset
(10 - (10 - (no * width)) / (no + 1)) / (no * width) = offset


You almost certainly don't have to do this. Just export the objects, then you can animate them in your game code. As for animations, I'm not sure whether those can be exported in glTF, but there should be a way to export them somehow.


How do I control the armature in weight paint mode?

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

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

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

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

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

Independently of Select with option:

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


Color palette as a replacement for the default color picker

Palettes are a rather nightmarish landscape because frankly, most folks don't understand what an encoded value represents.

That is, in software, an RGB triplet is an encoded representation of exactly two facets, both of which must be communicated via ancillary metadata beyond the three values themselves:

A value representing some degree of visual energy according to some typically unnamed and arbitrary scale. “What visual energy curve is applied to these values?”
Referencing typically unnamed and arbitrary coloured lights. “What colour of light do the three channels reference?”

That is, given an RGB triplet alone, you are missing the aforementioned two critical bits of metadata to decode an RGB triplet into meaningful data. Further, to close the loop, you would need the metadata of your existing context.

As you may have guessed, many palette formats store the arbitrary series of three values as their format, making the erroneous conclusion that such values have any meaning at all.

So the idea of a palette of swatches that has some meaning when used with some other arbitrary list of values is sadly delusional; in order to achieve this you must have an iron fisted controlled colour managed pipeline.

Pantone too suffers from this. Pantone is useful in so far that it references a series of spot printing inks. But how to communicate how a particular Pantone ink appears on a given paper under a given illuminant? A proper colour managed pipeline can accommodate this, but a random triplet of RGB values from some table or horrible website is woefully inadequate. It is a fool's errand and those that frequently seek such solutions by meticulously copying and pasting those RGB encoded values eventually wake up from the chemically induced haze and realize the complexity of any such endeavour.

In the end, there are tremendously complex transforms from a display referred subtractive system such as Pantone to a scene referred additive system such as the reference space that Cycles uses. Could you foreseeable bridge the two? Plausibly, but it would require quite a grasp on colour management and an application thereof.

TL;DR: Find precise chromaticity values for any given series of swatches in xyY and identify the illuminant / white point for the values. Transform the values to your working reference space, whatever it happens to be within your renderer. In Cycles default for example, this is assumed to be REC.709 lights with a D65 white point. Another option is to use an “All in one” RGB image (such as those used for 3D LUT generation), transform it carefully from the colourspace required to the destination, and then sample from that image.


Default lightning, or how to adjust materials properties correctly

I found solution in "Cycles Encyclopedia" written by Blender certified trainers Frederic Steinmetz and Gottfried Hofmann. (Available on blender store or blendermarket.) Authors use this "Blender Material Preview Scene" by Robìn Marin. So I thing this can be considered as default scene for Cycles material settings.


Simple python script to stitch images into movie failing with incorrect context

Ditch the operator.
Have updated the code from
Importing multiple movie clips inside one directory via script

look at all images in a path
glob on "*.png"
to use pathlib.Path

Adding each image as a strip.
import bpy
from pathlib import Path

# glob all movie files from
dir_path = "/home/batfinger/Pictures"
img_dir = Path(dir_path)
glob = "*.png"
frame_duration = 24
files = sorted(list(img_dir.glob(glob)))

# get sequence editor
scene = bpy.context.scene
#scene.sequence_editor_clear()
sed = scene.sequence_editor_create()
seq = sed.sequences

# add movie strips
for i, fp in enumerate(files):
    ms = seq.new_image(
            name=fp.name,
            filepath=str(fp),
            channel=i + 1,
            frame_start= i * frame_duration + 1 ,

            )
    ms.frame_final_duration = frame_duration
    # print some details
    print("%s ch: %d fs: %3.1f len: %d" %
            (fp.name, i + 1, ms.frame_start, ms.frame_final_duration)
            )

Adding images as sequence to one strip.
import bpy
from pathlib import Path

dir_path = "/home/batfinger/Pictures"
img_dir = Path(dir_path)
glob = "*.png"
frame_duration = 24
files = sorted(list(img_dir.glob(glob)))

# get sequence editor
scene = bpy.context.scene
#scene.sequence_editor_clear()
sed = scene.sequence_editor_create()
seq = sed.sequences
duration = len(files)
# add image strip using first
fp = files.pop(0)
imstrip = seq.new_image(
    name=fp.name,
    filepath=str(fp),
    frame_start=1,
    channel=1,
    )
# add the elements
while files:
    imstrip.elements.append(files.pop(0).name)

imstrip.frame_final_duration = duration
imstrip.update()


How to I get rid of these flippin' edges?

You cant dissolve those edges. Some polygons simply have too many sides. I fought this many times importing project from Autocad and applying wireframe modifier for cool looking render. Anyway in case of the ring how do you imagine polygon data saved without edge going through the ring? It is simply not doeable to make one face polygon ring without edge going this way.


Add the depsgraph.
Since 2.8 most handlers take both a scene and a depsgraph argument, the latter is generally a kwarg.
If set up as a simple function this is fine
import bpy
# test clear
bpy.app.handlers.frame_change_pre.clear()

def my_handler(scene):
    print("Frame Change", scene.frame_current)

bpy.app.handlers.frame_change_pre.append(my_handler)

However if using a method of some instanced class, the way blender is wiring this up under the hood requires the extra argument defined for depsgraph. (Even if it is always None in FCPre)
Code below, same result as code above.
import bpy
# test clear
bpy.app.handlers.frame_change_pre.clear()

class MyClass(object):
    def my_handler(self, scene, depsgraph):
        print("Frame Change", scene.frame_current, depsgraph)

my_object = MyClass()
bpy.app.handlers.frame_change_pre.append(my_object.my_handler)


Different image textures for one material (Cycles)

You could assign a Vertex Color layer for each texture. Then use the Attribute and RGBMix nodes:

To cut down on layers you could use a channel per texture:

Separating colours from a single layer can be done too but it's a little more complicated:


unexpected reactions in a quiet simple rigidbody physics simulation

I had no problems with the following settings:

Split Impulse enabled in Scene > Rigid body world:

Both the cube and the sphere with Mesh collision shape and Margin set to 0.

It is important in this case to set the Margin to 0 because the collision margin for mesh is not embedded into the object, so it will collide with objects that are near the object's surface but not actually touching it (unless it's set to 0).

It is also important to use the Mesh collision shape in this case, because Convex hull will collide with any objects in a convex part of the mesh.

To visualize this, have a look at the convex hull operator. Try applying it on a Suzanne, the result is roughly what Suzanne's collision shape would be if it was set to convex hull:

Applied to your cube object, you can see why it was causing a collision with the sphere:

Mesh is currently the only collision shape that can handle collisions with concave shapes. There was another shape developed in GSoC 2013 which also could handle concave shapes by breaking them into smaller convex shapes, however this is not yet integrated with blender officially.

The reason why Mesh is necessary for the sphere is because the sphere you are using is not a perfect sphere, while the collision shape is.

Since the concave depression in the cube exactly matches the "facets" of the UV sphere and the Sphere collision shape's radius is equal to the longest dimension of the object's bounding box, the sphere collision shape will intersect the cube slightly and cause a collision.

To visualize this, I have added a highly subdivided sphere to simulate the perfect sphere of the collision shape and scaled it so that it's radius is equal to the dimension of the UV sphere. I then used Clipping border to make only a tiny cross section visible:

As you can see, the "perfect sphere" intersects the cube, causing a collision to be detected:

The ground cube set to Box collision shape with a .04 margin (the margin is embedded for the box collision shape).
All objects have scale applied (CtrlA) and origins centered (ShiftCtrlAltC).

Result:

Example blendfile


Which is more efficient? duplifaces, particles, or group instances?

I do not know the specifics of Blender's implementation. But, it seems to me, they would use the exact same algorithm in both cases. With particle instancing, you have a position vector and a transformation matrix for each particle. The only difference with dupliface is the position vector is determined by an object's face, rather than a particle.

So, memory is going to be the same. Render time should be the same, unless you're using extra features. For example, you can have objects deform along a particle's path when using particle instancing. The deformations would take extra time to compute when rendering.


Joining an array before using a displacement displacement map

I'm not sure what your situation is without a .blend file, or at least some screenshots. The best advice I can think of is: Apply the array modifier before doing anything else. If your going to use a displacement map after, then I guess you'll need to UV unwrap again.
Hope this helps


Quickest way to create panel buttons with quick functionality

Main concept is that Operators executing something based on given data (e.g. convert all polygons of object xy to triangles). Properties on the other hand can either store the actual 'state' of something (e.g. Wireframe ON/OFF) or any 'value' (e.g. Subdivisions=3 or Crease=0.0001).

In fact, Operators like OPS.object.delete() can be called because these are 'functions' (note the parentheses at the end). However, a Property like Object.wireframe just stores True or False so it can not be called (it's basically not a 'function').

Means that you have to write an Operator if you want to change/toggle any Property.

Another way which you might not think of, is expanding each property to make it look like a 'Button', which also gives instant feedback to the user whether the property is ON/OFF.

import bpy
from bpy.types import (Panel, Operator)

# ------------------------------------------------------------------------
#    Operators
# ------------------------------------------------------------------------

class SimpleOperator(Operator):
    """Print object name in Console"""
    bl_idname = "object.simple_operator"
    bl_label = "Simple Object Operator"

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

# ------------------------------------------------------------------------
#    Panel in Object Mode
# ------------------------------------------------------------------------

class OBJECT_PT_CustomPanel(Panel):
    bl_idname = "object.custom_panel"
    bl_label = "My Panel"
    bl_space_type = "VIEW_3D"
    bl_region_type = "UI"
    bl_category = "Tools"
    bl_context = "objectmode"

    @classmethod
    def poll(self,context):
        return context.object is not None

    def draw(self, context):
        layout = self.layout
        obj = context.object

        layout.label(text="Properties:")

        col = layout.column(align=True)
        row = col.row(align=True)
        row.prop(obj, "show_name", toggle=True, icon="FILE_FONT")
        row.prop(obj, "show_wire", toggle=True, text="Wireframe", icon="SHADING_WIRE")
        col.prop(obj, "show_all_edges", toggle=True, text="Show all Edges", icon="MOD_EDGESPLIT")
        layout.separator()

        layout.label(text="Operators:")

        col = layout.column(align=True)
        col.operator(SimpleOperator.bl_idname, text="Execute Something", icon="CONSOLE")
        col.operator(SimpleOperator.bl_idname, text="Execute Something Else", icon="CONSOLE")

        layout.separator()

# ------------------------------------------------------------------------
#    Registration
# ------------------------------------------------------------------------

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

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

if __name__ == "__main__":
    register()

You should definitely read: How to create a custom UI?


Add a boolean property which is False by default. On collision, set it to True and play the sound only on collision AND if the property is equal to False.
Change the state on collision. States behave like layers, only the current active state(s) get executed. For a detailed explanation see: https://docs.blender.org/manual/en/dev/game_engine/logic/states.html


BGE place object on 3D graph based on user input?

I do not think the BGE is sufficient for text interaction or diagrams. It is possible, but not easy.

I suggest you look at something like presentation and/or table calculation applications.


The reason here is clearly low resolution of the fluid. Just increase the resolution. If your mesh walls are thinner than the fluid simulation cells, this will happen.


Boolean Modifier (Difference) Issue Persists Even After Applying All Transformations, Recalcing Normals, and Fixing Non-Manifolds

There are were inverted normals, so Shift+N to recalculate them.
Overlapping edges between boolean cutter and source object. This is healed by moving edge away from the cut. It's a front view: yellow edge is source, white is cutter:

Lots of ngons, so consider doing retopology. I added Triangulate modifier to make it more boolean-friendly:

Also keep boolean object's geometry as simple as posible, avoid excessive edges which doesn't contribute to final shape.


How to light an object consistently? Like a matcap

Matcap Material

Matcap Material + Your Texture (here as UV_Grid)

Workbench

Both examples here...


What kind of topological structures are there?

Your example shows geometry with Subdivision Surface algorithm on top.

Subdivision Surface works with quads, and when they're not there, it transforms the geometry.
Your image shows Subdivison Surface applied on top of triangles.


Weight paint brush does nothing to my mesh

It seems that you have 'Vertex selection masking for painting' ON.

Either turn that OFF or go to edit mode to select some vertices.

I hope this helps


Hold Ctrl then click the object name in the ouliner.


How to connect 8 vertices to 3 with all quads?

Your situation has an even amount of vertices.
They cannot be connected with only quads.
Each inserted quad will always add/subtract exactly 2 vertices to/from a hole and you will always end up with 3 vertices in the end.
After adding one more vert you can easily achieve quads for example like this:


How about using gravity? If you put gravity as z=10 (i.e. pushing upwards) and y=10 (pushing against back of stacker), then that would do the stacking. If you then animate the Physics/RigidBody/Settings/Dynamic toggle, you can turn gravity off for each object until the stacker reaches it.

You might want to use an invisible plane or two as passive rigid bodies to control the movement, as the stacker geometry is relatively complicated so might not work well as a collision object.


Did you look closer of your UV in image mode? The UV coordinate sometime give a small error upon manipulating (Floating-point error).

And if you want a clear edge of checker pattern, change the interpolation method from Linear(Default) to Closest as below:

And for precisely assign UV, use your pivot point:

1. Unwrap your mesh

If your mesh is a clear plane with square and rectangular, a normal nuwrap can do the job, check if the UV mesh is rectangular and perpendicular in UV editor.

2. Set Pivot to 2D Cursor

Once you enter the UV editor with the mesh, you can see the UI panel on the right, there is a 2D Cursor similar to 3D Cursor, set it to (0,0) if the UV map can scale from origin.

Or you can choose any location once upon you know how the pivot point work.

3. Scale your UV to specified value by directly type in number (aspect ratial of your rectangular)

The number just like a virtual text input block. It is a pretty standard parser in a  lot of application, even Photoshop use number pad to type the value of layer transparency. Type down the number, you can see it in the bottom of the status bar(if you didn't toggle off the bar)

This should work as below:

This method only solved the general checker pattern. If you want a more complicated mesh, I would recommend using script for it.

Addition

What does closest interpolation do and why is it necessary?

Closest interpolation give you a sharp image texture, while using linear method, your checker edge will be blur out if resolution is low. Not necessary, but I will do it if I want a sharp edge(it also improve a little tiny performance, just a little).
Why do we need to set the pivot point to 0.0?

You can set the pivot point to else where, if the UV origin you want to scale is known (you can read the vertex UV value in UI Panel). But most of the time Blender put unwrap vertex in 0.0, 0.0.
Am I right to change the interpolation in the node editor of my material?

Yes, node editor is the most common and general place you can change your shader behavior. The image textures node by default use linear for scaling, just because it is a common and light weight method to deal with 2D scaling. Feel free to change it if the linear method is too coarse for your rendering (I love Lanczos BTW, but Blender didn't implement it)


Mac computers do not play avi files unless you use another video player to see it.

I recommend you to render your movie in mp4 format.

See this related answer:

MP4 video settings


Another way to do it would be to use the Screw modifier:

Create a simple edge, move it away from its origin:

Give it a Screw modifier, play with the Angle value:


Why does increasing resolution and then downsampling to desired size increase render quality?

If you render at 256x256, each pixel gets only 16 samples of AA.

If you increase the resolution to 1080x1080, the same area is now covered with 16 pixels (4x4). So the area now get's 16 times more AA samples.

By rendering larger you get also less noise in the image on the Ambient Occlusion and that also helps with the clarity when sampled down to small size.


Fire appears in preview, only renders emission

I recently had a similiar problem. Your render, in fact, is correct, but the result is displayed incorrectly. This is due to the way alpha is represented in the viewer, which uses straight alpha rather than premultiplied, so emissive volumes like fire can't be properly modelled. For a detailed explanation, see this answer.

To see the fire, just try switching to RGB mode instead of RGBA in the image viewer and you'll see the flames:

As suggested in the linked answer, a solution would be to use an EXR image wich has premultiplied alpha. If you can't use an EXR however, you need to convert the premultiplied alpha to straight alpha in the compositor, then save as e.g. PNG:


Can we Trigger AN with 'Active' camera object location change?

You can use a Scene trigger with the path camera.location.


How to reveal type of material nodes in 2.8

This seems to be a Node Group.
It is not a node by itself - rather a kind of a directory/folder.

It contains a node tree, with different inputs and outputs.
To enter or leave it press ⇥ Tab or the little top right arrow

Inside of a node group.

It is used to organize complex node trees, or sharing node trees across materials.
You can also rename your group, or the nodes inside of it - so it's easier to navigate.

Further reading:
Node Groups Page in Blender Manual


Start to render when you go to bed?
If the render is not completely done in the morning, just continue from the last frame of the previous render session.

If that's not enough of an answer, please provide more info.


Is it possible to isolate parts of an armature so the mesh will never deform?

You could select the shell in Edit mode, go in the Properties panel > Data > Vertex Groups, on the right of the vertex groups list, click on the down arrow button and choose Remove From All Groups. You could now assign these vertices to your big body bone vertex group, or create a new bone, child of this big bone, give it a name, create a vertex group with the same name and assign your shell to it, so that you have a bone completely dedicated to the shell, if you ever need it to move slightly differently sometimes.

You say "I thought that I could paint the weights by bone, but it looks like it's only possible to do so by the whole armature (at least from what I can tell)", I'm not sure what you're saying, maybe you're missing that if you switch your armature to Pose mode, then select your mesh and switch to Weight Paint mode, you can select one bone and see what influence (i.e. vertices groups) it has on the mesh.


Plane rendering in render preview but not when performing an actual render

As @Leander said in the comment, I had disabled rendering in the objects property. Enabling it worked.