How do I form planes into existing object?

You could do it with a procedural texture, but if you absolutely want to use an image texture, I see at least two ways to do it, tell me if it answers.

First, as Keavon says, you could UVmap your object with a texture.
Prepare your texture, it needs to be tileable.
As your object is already made, create a seam along an edge, and unwrap.

Your object is not orthogonal, so it will be displayed as a twisted mesh in the UV/Image Editor. It won't allow the image texture to be repeated seamlessly, so you need to orthogonalize your UV. To do that you need to use an addon like UV Squares. Once installed, open the T panel on the left of the UV/Image Editor window > Misc, press To Square Grid. Rescale the UV on the Y axis and on all axis, move it...

Don't forget to plug the Image Texture node into a Diffuse in the Shader Editor. Now your uvmap is orthogonal and the image texture will repeat seamlessly. Advantage of this method: you need only one picture and it doesn't need to be big as it is repeated. Small problem with this method: the texture may be a bit distorted on some parts.

The second method would be to paint the texture on your whole object.
Prepare a second material, create a second UV map for this one, this time unwrap with the Smart UV Project mode. Create a new (black) image in the UV/Image Editor with the "+" button. This image needs to be large enough because it will have to cover the whole object, so you need to decide, depending on your final goal. Plug the Image Texture node in the Diffuse, and load this new image. Put an Input > UV Map node before if you've created a second UV map.

In the 3D View switch to Texture Paint mode. In the T panel > Tools > Texture, create a new texture, and in the Properties panel > Texture, choose Brush - Texture to determine what texture you will use for your brush, choose your cave wall texture (doesn't need to be tileable this time).

On the T panel > Tools > Texture > Brush Mapping, choose Stencil. It will overlay the texture image on the 3D View and allow you to project it on your object. To be complete about stencil, how to change its position here.

You should be able to paint your object, and the painting will appear on the new image you've created in the UV/Image Editor. Advantage of this method: You can apply the texture as you want on the object, it may look more natural. Disavantage: As it is not a repeated pattern you need a big image that covers all your object.

With both the 2 methods, to make everything more realistic you need to complicate a bit your nodes organisation: add glossiness and bump maps, etc...


How to animate 'Bridge Edge Loop' effect

The main issue I see with bridge edge loops and using a mesh for this, is that it will be very hard to control the deformation of the mesh as it moves It would require some rigging (bones and an IK system) to work correctly, in my opinion is too much trouble.

An alternative would be to use curves and hooks.

Here's a curve with some bevel. You can control the radius of each point separately.

To add hooks, select one of the control points, press the space bar and type hook, you''l get the option "hook to new object". That will create an empty.
Do the same for the other segment of the curve and animate the movement of the empties.


"Extrude poly ribbon" (ctrl+click) not working for me

Mac: If the answers above don't work for you, try: ⎈ Ctrl⌘ Cmd LMB

In order for ⎈ Ctrl⌘ Cmd LMB to work, you must have "Emulate 3 Button Mouse" checked.

To do this: File > User Preferences > Input tab > check Emulate 3 Button Mouse box


Fluid failing to enter side channels in Blender 2.80 fluid simulation

First, in the Domain options Set Boundary to Free Slip. With just this change in the file you attached I got as far as this:

You could probably play with subdivisions / surface smoothing or make the timeline longer. It might also help to make the domain only as high as the obstacle, so the fluid doesn't overflow before filling the smaller channels.


Create terrazzo material/pattern with the standard textures

Just switch a Voronoi texture to Cells coloring, and drive it through a Color Ramp node set to Constant interpolation mode.

Adjust the Color Ramp stops to the desired color ratio so that the amount of colored flakes is close to the reference image.

You would generally want narrow black, orange and green strips, over a broader white background, so adjust proportions accordingly.

Speckle size can be adjusted from texture scale parameter. Changing size may also require adjusting color stop positions.


This can be done very easily in the compositor. I am using the Cycles node set in this example.

First, press Shift+A and add an Ellipse Mask node.

Do the same for a Blur node.

Then hook up the nodes as shown. Animate the Width and Height values by keyframes to animate the effect.

Depending on your render size you may need to adjust the blur size, but this should get you on the right track.


Baking is only avaliable in the Cycles Render Engine.
Switching to Cycles in Render Properties gives you the needed Baking panel.


Argument works in the python console but not in a loop?

You're testing all of the objects that were selected when the script reached the line
fbxs = [ ob for ob in bpy.context.selected_objects]
One of these objects has no parent, so when the line ob.parent.select = True is run, Blender tries to find a parent and raises an error when it doesn't find one.

Try this instead:

if (ob.parent):
    ob.parent.select

or if that doesn't work for some reason, enclose it in a try:/except: block.


Cell Fracture not appearing when activated

As GiantCowFilms said, the cell fracture addon is used in object mode:


Without knowing the specifics of the Maya feature, try pressing . on the your keyboard's numeric keypad. This adjusts your 3D View to focus on the selected object. You can also press / on the numeric keypad to get a "local view" of the selected object (pressing / again will pop you back to the scene view).
To show all non-hidden objects in the 3D View, press Home.
For purposes of remapping, this keymap is called Frame Selected under 3d View.


How can I change the transform by minimal code?

if you want to get exact code you shouldn't change transform in view port.
when you change the transform in this panel it works:

Location
import bpy

obj = bpy.context.object
obj.location = (0,0,0)

Rotation
import bpy
import math

obj = bpy.context.object
obj.rotation_euler = (0,math.radians(90),0)

Scale
import bpy

obj= bpy.context.object
obj.scale = (1,1,1)


I think problem in clipping settings:

The end point is extremely big! Set end point less than one thousand.


I need help trying to create piping that goes along a curved surface for half of it, then curves out away from the surface

Perhaps an alternative approach to shrinkwrapping is as follows: (It's not easy to make illustrations for this one, so I'll just try to decscribe it)

Duplicate your smokestack and tanks
Enlarge the duplicate appropriately, scaling (S) or fattening (AltS). This object is going to be the 'Form' for your pipes (they lie slightly outside the objects they are aligned to.)
Simply select edges from the 'Form', where you want the pipes on the cylinder. Don't worry about the right-angle corners, we'll get to that. If the edges don't exist, subdivide, or cut using the Knife (K) tool.
Duplicate (ShiftD) those edges, and extrude the end vertices of the duplicate sections to create the splaying straight pipes. If your model is up in Z, that will be - Select vertex, EShiftZ for the horizontal sections, and EZ for the plunge into the tank.
Separate the selection of edges (P) into a new 'Pipes' object - and bevel (CtrlShiftB) its right-angle corner vertices to give them the curve you're looking for.
Convert the 'Pipes' mesh into a Curve, and in its'Shape' and 'Geometry' panels give it a Full Bevel profile with enough resolution to make the pipes round.
If you've kept the resolutions reasonable , and dissolved out vertices in straight sections which are not contributing to the shape, you might want convert back to mesh, and put a subdivision surface modifier on the result.

I short, the method takes the vertices from existing geometry, rather than creating shapes from scratch.


Blender stores a list of the currently selected objects in bpy.context.selected_objects. It's not always as easy as this, to only effect the selected objects, but for your example you would access the current action of the selected object with the animation_data.action property:

import bpy

for object in bpy.context.selected_objects:

    for fcurve in object.animation_data.action.fcurves:

        for point in fcurve.keyframe_points:

            point.co.x **=2


Python: doing an action depending of the type of object

You are trying to assign 'EMPTY' to "bpy.context.object.type" within an if clause.
For checking the value of something, you need to use "==", not "=".

if bpy.context.object.type == 'EMPTY':
    bpy.context.object.location[0] = 8.46184


Blender connected proportional edit in UV/Image editor not working

Unfortunately proportional editing in the UV editor works differently to the 3Dview. In the 3Dview connected proportional editing will only move vertices that are directly attached to the selected vertices that you are moving. In the UV editor all points that are indirectly connected are influenced by proportional editing.

A possible solution is to select only the vertices you want to move (in the 3Dview), the unselected vertices will not be visible in the UV editor and will not be moved when you move the nearby points. Note that this can tear apart neighbouring faces at the edge of the selection.


How can I scale faces without moving them?


Driver with animation data as var target
There is a way to do this using the animation system via drivers to "answer the question  as posed"  Would look into other ways of doing this with say driving track to constraint influences to randomly located objects, or by baking an animation.
Proof of concept
Using NLA strip data as a driver target.
Have a scene with a cylinder that rotates 360 (one revolution) via a 2 keyframe action that has keyframes at 1 and 24.
It is added as a strip to NLA track "NLATrack" the strip has been given the arbitrary name "XXX".

A cone is added to the scene with a driver on its Y Euler rotation.  It uses a method we are going to define later.  The animation data of the Cone object is single property var named "ad"

The script.  Defines a list of random angles choosing from  -90 to 90 degrees with 5 degree steps.
The method point takes the animation data of the cone as a variable.  From this a strip named "XXX" in the track "NLATrack" is found.
From the strip  get the repeats, from the action the action length and other info.  Haven't made a good fist of getting the maths just right by checking other strip properties like start frame etc.
For each repeat there is a random number added to a randoms list available to the driver namespace.  (Will not be saved with blend file)
The current repeat is calculated by the whole number dividing the current frame by frames in action.
How far between this and next repetition is the linearly interpolation of remainder of current frame divided by frames in action divided by frames in action.
import bpy
from bpy.app import driver_namespace as dns
from math import radians
from random import choice

dns["randoms"] = dns.get("randoms", [])

def point(ad):
    if not ad:
        return 0
    frame = dns["frame"] # current frame
    strip = ad.nla_tracks['NlaTrack'].strips["XXX"]
    action = strip.action
    repeat = int(strip.repeat)
    nframes = int(action.frame_range.length)
    randoms = dns["randoms"]
    if frame < 0:
        print("Reset Randoms")
        randoms.clear()

    while len(randoms) <= repeat + 1:
        randoms.append(radians(choice(range(-90, 90, 5))))

    rep = min(int(frame // nframes), repeat)
    drep = (randoms[rep+1] - randoms[rep])
    #return randoms[rep]
    return randoms[rep] + (frame % nframes) * drep / nframes

dns["point"] = point

First image below shows result of uncommenting (removing hash #) from
        #return randoms[rep]

Second with the linear interp.


Scaling has not been happening from the center point

So, in the Pivot Center option, instead of Active Element, choose Median Point:


Cannot Select Linked When Sync Selection Is Enabled

That's nothing about UV in this case. That's because you were trying to tweak pose in Rest position. Just remember to simply switch to Pose Position to continue tweaking. :)

Location:
Properties Editor > Object Data Tab > Skeleton > Pose position

BTW, there are indeed two such messages, located in:

source/blender/editors/transform/transform_conversions.c
source/blender/editors/uvedit/uvedit_ops.c

True, it's a strange message for bone transform system, which seems hard to make sense, probably needs to be improved.

Edit:

In the latest build, this puzzling message has been fixed as "Cannot change Pose when 'Rest Position' is enabled". So it is not an issue any more.


How to import a .max model into Blender?

.max is the native internal format of 3DS Max, just like .blend is Blender's native format. To get models into blender use an interchange format such as Obj, Collada or FBX.

If you only have the .max file and no access to 3DS Max, then yes, there's no way to import it into blender, just like there's no way to import a .blend file into Max, or a .max file into Maya.


dirty vertex color with the multiresolution

Not currently. I know of one person who has been on a campaign over this issue for a long time now.
I always have UV's built early so what I do is duplicate the object then move it to another layer.  Then I apply the modifier and bake the results to a texture.

Then I delete the duplicated object and apply the baked texture to the original model which still has the modifier.

Once you get used to doing this it can be usually be redone within a couple of minutes so you can redo it easily if you have updated the mesh and require a rebake.

Here are the relevant bake settings that I use.

BTW, even though there is a bake pass type called Vertex Colors, it does not produce the results that I expect.  For me it always bakes much darken than it should but maybe I'm doing something wrong.  The settings I showed here work well.


node.add_node by code -> use_transform doesn't work

There are two operators called: bpy.ops.node.add_node() and bpy.ops.node.translate_attach_remove_on_cancel(). To get the same result, you put the second(modal) operator in your return and use the INVOKE_DEFAULT option:

class NODEEDITOR_texture_image(bpy.types.Operator):
"""Image Texture\nHere you can load an image as a texture"""
bl_idname = "node.texture_image"
bl_label = "texture image"
bl_options = {'REGISTER', 'UNDO'}

def execute(self, context):
    bpy.ops.node.add_node(type="ShaderNodeTexImage", use_transform=True)
    return bpy.ops.node.translate_attach_remove_on_cancel('INVOKE_DEFAULT')


Texture showing in preview render, but not in finished render

you have hidden some objects from the viewport but not from the render
change from this

to this


Find the frame when passing a certain point on the path with the path animation

Adjusted with Delay Action and Curve Interpolation.
I made an interpolation curve with reference to From Fcurve.
Thank you to everyone who looked at the question.


It seems you start the simulation from frame 1000 - It might be so that you need to start from 0 or 1. At least then it started to simulate for me (after adding the cloth modifier and pinning the flag)

You can increase the simulation from 250 to 1250 from the Cloth's cache settings:


Why when importing an obj file nothing appears even when zooming?

The first thing you have to check is if there are any objects on the Outliner Window.

If there are, that means that you've successfully imported something. Then is just a matter of finding where it is and at what scale it was imported.

Select the object in the outliner and pres Numpad Period to center the display on the object.

You might need to adjust the Clipping Distances on the 3D viewport's properties panel (N) if the object is too large or too small:

Blender 2.8x

Blender 2.7x

Sometimes the mesh can far away from the actual origin of the object. In that case it might take a bit longer to find the geometry, as the  Numpad period  will center the view on the origin. In that case you can enter Edit Mode Tab, press A to "select all" of the geometry and press  numpad Period  again this time to center on the selected vertices.

Read: Unable to see anything after importing .obj file and obj file not displayed properly


Cycles Material Texture not showing in render

Your UV map is disabled.

Enable it in Properties > Object > UV maps by clicking the camera icon next to your UV map:


I thank God for one interesting and unexpected hack He showed me. This might help someone if your scene falls within the following criteria:

If you have a lamp inside some occluding geometry, AND the shadow of the occluder happens to fall across a mirror surface with a reflection plane applied, THEN you can increase the lamp's "Bleed Bias" (I used 0.05) and the SHADOW will actually erase the lamp from the mirror's reflection. Note this only works if the shadow falls across the mirror surface. Proof below:

With bleed bias at 0:

With bleed bias at 0.05:

With bleed bias at 0.05 and reflection plane on floor. Note how the reflection of the lamp shade improved, but now you lose the ability to see the mirror's reflections in the floor's reflection (no reflection of reflection). EDIT: Technically, from this angle, the floor would not reflect the mirror's reflection but rather the ceiling. Cycles confirms this. However, Eevee is still incorrect since the floor's reflection plane cannot reflect ANYTHING in the mirror's reflection planes.

EDIT: Here is the Blend file including one occluded light (inside the lampshade) and one non-occluded light floating in space. You can see that the shadow of the occluded light only erases itself, NOT the other light floating in space. Each light would need its own occluder.


A strange problem with rendering glass in Cycles

After pressing random buttons, and trying to fix mesh - successfully i did it!
There was problem with my mesh - gaps caused mirror modifier, and some other things.

There is how I fixed it:

At first I was searching for something wired in mesh, found not connected edges, so I selected them.

And scaled them down. pressed s + x (axis of scaling) + entered 0 on keyboard

After scaling them together i removed doubles by selecting all edges press two times a then click w > Remove Doubles

In the end, with selected mesh I pressed Mesh>Clean up>Split Concave Faces...

And Voilà!

 :)


How can I create a stained glass light effect?

Add a spot lamp, then go to texture panel, clic on the lightbulb (lamp texture) and add your texture.
I don't use BGE so I couldn't help more with it, but it looks like what you want.


How to draw shapes in 2.8x from a script - does bgl still work?

BGL still works. The old snippets used fixed function pipeline which is no longer available in Blender since it is running on OpenGL Core profile. Programmable pipeline for OpenGL is actually much easier, more understandable and a more streamlined way to do things. Just use regular modern tutorial for OpenGL to draw a rectangle, make sure that tutorial is using Core profile, and not FFP.

In order to draw outside the viewport, you need to hook your draw handler to multiple Space sub-types, and determine visibility on what you draw based on the cursor position.

You can use GPU module alongside with BGL (technically it is also an OpengGL wrapper. The only difference is that BGL is a direct 1:1 mapping of OpenGL function calls and GPU module provides a set of convenience classes to automate certain common tasks. But they are still using the same single OpenGL draw context.


Comprehensive list of 'missing' features in Blender 2.8?

Blender 2.80 has solved all of these aspects.

  Stable and well documented Python API for add-ons developers.

The Python API for 2.80 is documented in the manual. The API was completed on 24th of May, 2019. It's stable in the sense that there are no major changes between 2.8x releases at the time of writing. Add-ons written for 2.80 continue to work in 2.81 and 2.82.

  User interface for Collections in the 3D viewport.

I assume this refers to the updated outliner. This has been completed, collections and view layer replace the old render layer system from 2.79. The concept is explained in the View Layers and Collections post by Dalai Felinto on the developer blog.

  Keymap for left-click select that works well with the new tool system, and a new keymap compatible with other software.

The new keymap system allows you to choose between left- and right-click select. You can create completely customized keymaps. There is an Industry Compatible keymap included in Blender which may help professionals to transition from other 3D software.

  Making image empty objects a fully-featured replacement for background images.

There are two image object types, the Reference and Background objects. Both are based on empties. This is only for images that do not appear in the render though. If you want your image to appear in the render, then the Image as Planes add-on is still quite useful.

  Restore support for all the physics systems within the new dependency graph.

The major dependency graph changes have been completed. Some technical information about the design can be found in the wiki article Blender 2.8: Dependency Graph.

  New subdivision surface and multi-resolution modifier implementations based on Pixar’s OpenSubiv.

The modifiers now use OpenSubdiv which has been integrated by Sergey Sharybin.


Make sure that the separate objects joined together are all carrying the same material, and that the texture to be painted on is in that material. Also, make sure that you are not also seeing duplicate objects that are persistent in the viewport - try moving the main object to another layer and see if anything is still on your main layer.


How do I add a Panel to the Rigid Body Panel?

The PHYSICS_PT_rigidbody_panel class is only present in the properties_physics_rigidbody.py script - it is simply a base class to provide common properties to the other panels in that script.

The step you are missing is bpy.utils.register_module(), with the properties you need for the panel you get the following -

import bpy

class PHYSICS_PT_rigid_body_worldmatrix(bpy.types.Panel):
    bl_label = "Rigid Body Coordinates"
    bl_space_type = 'PROPERTIES'
    bl_region_type = 'WINDOW'
    bl_context = "physics"
    bl_default_closed = True

    @classmethod
    def poll(cls, context):
        obj = context.object
        return (obj and obj.rigid_body and
                obj.rigid_body.type == 'ACTIVE' and
                (not context.scene.render.use_game_engine))

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

        ob = context.object
        rbo = ob.rigid_body

        row = layout.row()
        row.prop(ob, "matrix_world", index=12, text="X")
        row.prop(ob, "matrix_world", index=13, text="Y")
        row.prop(ob, "matrix_world", index=14, text="Z")

if __name__ == "__main__":
    bpy.utils.register_module(__name__)


Orthographic camera mirrored in viewport?

This is because the Object mode Mirror tool works by scaling -1. (the same thing will happen if you manually scale the camera by -1.) You will also notice that in addition to the viewport being mirrored, Object Normals appear reversed.

from the wiki about Edit mode mirror:

  The mirror tool in Edit mode is similar to Mirroring in Object mode.
  It is exactly equivalent to scaling by -1 vertices, edges or faces
  around one chosen pivot point and in the direction of one chosen axis,
  only it is faster/handier.

note that using an Orthographic or Perspective camera does not change this behavior. It is the same on both.

(as already mentioned by Polosson),
The solution is to Rotate the camera instead of mirroring it.

Also as already mentioned by Polosson, one way to do this would be to

Select the building, and press Shift+S > Cursor to selection
Press . to change the Pivot point to Cursor
Select the Camera and rotate around the Z axis by 180 degrees. (R+Z+180)


trying to make a "glow" effect on a scene to be composited over VSE

The only way I could do it was to produce two separate movies/images.  One for the black obects, the other for the white objects which are blurred when mixed in the compositor.

Here are the nodes...

One thing to check is your Render output;  Open the "Post Processing" tab, make sure PNG format is selected, and also set it's RGBA box to on. (highlited) to ensure the Alpha Layer is included in the render.

Note that a separate folder for the output png files, (one for each frame) is a good idea.

The rendered pic I got was as we see in the backdrop above, complete with an alpha layer and ready to overlay another pic or movie as required.

If you're stuck I can attach the Blend file...

ADDENDUM:
Here's how my output looks when overlaying an image or movie -

The mixing/scaling can also be done in Blender's 3D window.  I tried that and the result was the same.

The Blend file follows and will open up in the 3D window which holds instructions on how to recover the two images needed for the compositor.


Exporting FBX to unreal engine deforms my mesh

The issue was having shape keys on the mesh, i made a new shape key from mix, set it as the basis and then deleted every shape key, deleting the new shape key as last and that fixed it.


A mesh "jumps" forward after parenting to an armature

Here is an example of an armature, edited in pose mode and, after this edit, made parent to the mesh (a cube):

This involves a 'shift' between pose and edit mode.

You could say 'there is no stable position for the mesh'.

To correct that, two possibilities: move the pose back to the edit position, or move the edit position to the pose.

Move the pose back to the edit position

To do that, simply use the pose menu, go to 'clear transform' and select 'all'. Doing this the pose will come back to the edit position:

Move the edit position to the pose

This time, we use the pose menu, go to pose then 'apply' (or CtrlA) and choose 'pose as rest pose'. Doing that, the edit position will be the pose position.

In both approach, the result is bones positions are the same in edit mode and pose mode (which is the best practice to define a 'stable' or 'reference' rest pose).

Depending on your need, you may have to parent mesh to armature again after that.

Additional indications: to avoid all that, adjust the bones in edit mode, not in pose mode. Also, if you scale the armature to the mesh, don't forget to apply this scale (CtrlA) before parenting to the mesh.


Cloth Pinning checkbox missing in Blender 2.8

Oh I missed that!
It is under Shape Menu.


Make dialog windows windowed and not fullscreen by default

In the system preferences > Interface > Editors > Temporary Windows , change  File Browser from Full screen to New Window.


Viewport and render artifact with distant objects

Internally, Blender uses floating-point numbers to represent vertex coordinates. Floating point numbers can represent a very wide range of values, but they grow increasingly imprecise at very large or very small scales. The Working Limits section of the Blender documentation gives some example precisions at various scales.
If you want to work with very large coordinate values, you can use the Unit Scale scene property to globally scale everything in the scene into the numerically stable range. Of course, this has the consequence of making smaller values less precise, so you ultimately just need to pick a scale and stick to it.


Creating a driver on a constraint with python?

Add the driver to the object, the data path is relative to that:

# We want Object.pose.bones[...].constraints[...].rest_length
# So use an object and the data_path 'pose.bones[...].constraints[...].rest_length'

BaseLenghtDrv = bpy.data.objects[armature].driver_add('pose.bones["'+str(GrpName)+'_bone"].constraints["Stretch To"].rest_length').driver


Blender 2.74 loop tools make circle disappear

Your object has a pretty extreme object scale on it. To get an idea of how extreme, this is what it would look like without it:

If you apply the scale to the mesh with ⎈ CtrlA it then works as expected:

See Why are the longer edges being beveled more? for some more detail. Suffice it to say that loop tools sees the mesh without the object scale, and that tall thin hole is confusing it.


Best way to make smooth UV sphere with hole through it

I can think of three ways to make this shape, not using a boolean.
Using a UV sphere (this is the best way), scaling a torus, or modeling it from a cylinder.
I'm not going to show the cylinder, because the other two methods are better, and after seeing them you will already know all the techniques used to model it off of the cylinder.
I'll start with the UV sphere.
With a default UV sphere, Tab into edit mode. Select both the top and bottom vertices at the polls of the sphere. Press CtrlNumPad + once, to enlarge the selection. Delete those selected vertices X > Vertices.
Select the inner edge loop on both the top and bottom, AltRMB to select an edge loop.

Now with that selected bridge the edge loops. W > Bridge Edge Loops.
Add one to the Number of Cuts while the bridge edge loops operator is still active.
Select the only edge loop in the middle of the new bridged part, and press CtrlB to bevel it. Move the edges until they are closer to the corner (this will make the subdivision surface look better).
A gif of all that:

Scaling a Torus
Add a torus, and change the Minor Radius so that the "hole" is smaller.
Now what I like to do is add a sphere in the same spot as the torus, it will only act as a guide.

With the whole torus selected, scale it to make it fatter (with the default rotation that would be along the Z axis).
Now select the bottom and top edge loops, and scale them along the Z until they about line up with the sphere guide in the background, this makes it look more round and less torus like.
Do the same for the first pare of edge loops on the inside of the "hole". At this point it looks like a sphere with a hole, not a torus.
Only thing left to do is straighten the inside of the hole. I did this by dissolving the middle three edge loops into one, then just scaling it to the same size as the top and bottom.
Again an nice gif of the above process:


How to render a background image in 2.8?

To do this without making it the background of your whole scene like handle does, I reccomend the images as planes addon.

This makes your image displayed on a mesh plane, meaning it will show up as desired in the render.

First enable it in the preferences:

Then just add an image as a plane from the add menu:

And then it should show up in your scene as you want.


Why does my texture look fine in preview but not when rendered?

You are using a normal map texture only. You need 2 textures: the bump map, and the diffuse. The following image show the steps for setting up the two textures:


When I tick the use nodes button no nodes appear on my screen

This can have multiple reasons.

You can try View > View All, (Home) to show all present nodes.
If there are none, you can also add them manually through Add > Search


How can I change a set of objects colour transition location in Z Axis?

You can use 'object' from the texture coordinate node :

The object output (from texture coordinates) is decomposed into X, Y, Z. Here only Z interests us.

The math node is here to tune the overall scale (real Z variation) to fit into the ramp (0 to 1).
I used divide and 12 as value because the stairs here are 12 meters tall.

On right : the stairs made with an array modifier
On left : separated objects

Edit : note that the colorramp is not mandatory here. You can short circuit it.


Can I create a noise texture with a "darker end"?

You can add multiple materials to an object in Blender. In Edit Mode just select the faces of the outer part and assign them to a new material. In the example I've done this for the outer, middle (white line), and the inner part.
The "darker end" can be created with a ColorRamp and a MixRGB node in the node setup. Set the mode of the MixRGB node to Multiply and factor to 1.0. To move the "darker end" of the outer part to the bottom right I had to add a Mapping node and rotate the position a bit.

The shading for the inner area looks similar. Just swapped the grey values of the  ColorRamp to darken the top right part of this area a bit.

If the colors appear too dark you might need more light in your scene. The logo on the screenshot is 3m tall (to get the shading right) and there is a 3000W point light, 3m radius (affects the shadow softness).
With a Solidify modifier you can add some depth/3D to your logo and it gets some nice light reflections. Add a plane as background to see the drop shadow if you want.
I removed the Alpha channel since it's always 1 and it had no use(?). If you activate the Node Wranger addon that ships with Blender you can press CTRL + SHIFT + LMB to get a preview of the selected node. This can help a lot to see what's going on.


Fluid inflow looks like a "shower" - How do I make the inflow more "cohesive"?

I can think of two reasons, either the inflow object is the wrong shape or its inverted inside out.

Try to recalculate the normal's or switch to a different shape like a cylinder.

If you upload your .blend, I can make one with your specific example
https://blend-exchange.giantcowfilms.com/


Empties have no geometry

You are using an Empty object to display the image (you can that from the icon in the outliner), but as stated by the manual:

  The “Empty” is a null object. It contains no real Geometry, [...]

This means that the object has no faces, no materials, so the engine has nothing to render. What you see in the viewport is just a "gizmo", useful to work with but has no influence on the rendered image.

The Image-Empties can be useful to quickly put some movable references in the scene. If you want to render the image, I would suggest to use the Images as plane add-on, that starting from an image create a true object in the scene.


Why are there borders around faces when I extrude?

If you create a new file, create a cube, or use default one, subdivide it, select some faces and hit E only once for every time you want to extrude, there should be no borders around the extrusion:

It would be a common beginner mistake to press E a few times this way creating more extrusions so this might be it. You could just start over from scratch since this is not very complex and the objective here is probably more to learn then to save a few minutes.


Is it possible to create instance with different scale animation data but the same mesh with python?

Here is a test script, select an object(s) and run. It will add the selected objects to a group, remove any animation already on those objects. Then using the group create 20 group instances with random locations.

Using code similar to here to create a simple 2 keyframe random scale action

import bpy
from random import uniform

def random_scale_action():
    action = bpy.data.actions.new("RandomScaleAction")
    data_path = "scale"
    # (frame, value) for keyframe point
    for axis in [0, 1, 2]:
        # new fcurve
        fc = action.fcurves.new(data_path, index=axis)
        # add a new keyframe point
        fc.keyframe_points.add(count=2)
        for kfp in fc.keyframe_points:
            kfp.co = (uniform(1,100), uniform(0, 1))

    return action

context = bpy.context
scene = context.scene

# create a group and add the selected objects to it.
group = bpy.data.groups.new("CubeGroup")
for obj in context.selected_objects:
    # remove any animation data.
    if obj.animation_data:
        obj.animation_data.clear()
    group.objects.link(obj)
# create 20 randomly located dupli_groups.
for i in range(20):
    instance = bpy.data.objects.new('dupli_group', None)
    instance.location = [uniform(0,10) for i in range(3)]
    instance.dupli_type = 'GROUP'
    instance.dupli_group = group
    scene.objects.link(instance)
    instance.animation_data_create()
    # give a random scale action
    instance.animation_data.action = random_scale_action()


How can a rigged model be used multiple times in a scene?

One you have imported the model. You can add it to the scene just as you would add any other object. Just open the Space Menu and go to Group Instance and you should see a new entry there for the rigged model.


can't read custom property from linked material using python

Unless defined as a bpy.props property hasattr won't work. . Use material.get("prop") or check if "prop" in material.keys()


How can I add a second colour to an object?

What you are doing at the moment (I think), is applying different materials with different colors to certains faces i.e. parts of the mesh. The example image you posted is using one material for the complete mesh and distributed by some texture which is used as mix factor between two colors. A simple example - very simple, you can do so much more complex things, but I would suggest you watch more tutorials on these things because this is too much to put in single answer here - you can see in the following screenshot:


How to extrude surface keeping face angles

As far as I know it can't be done with extrusion directly, but it can be approximated using the Move Along Normals operator.

Select the desired face and press G,G (G key twice) to initiate the Move Along Normals operator.

Move your face "backwards" towards the existing geometry so it slides along existing edges and Blender picks up the correct directions. Once along the desired edges, while moving, press C to unclamp movement.

Once unclamped you can now freely move "forward" towards opposite direction, while still keeping the alignment of the previous geometry.

The downsides of this method are that you won't be able to move in absolute distances in Blender units, only in percentage increments, and there won't be an edge left at the original position, if you did want to keep one there.


how do i connect a sun lamp to a sky texture with a sun in eevee 2.92?

Yea sorry I figured out by using this link as a guide, tho I did have to make some edits as I had an actual sun texture, course now I have to figure out how to make a moon texture.
how to parent my sun to environment hdri?


The closest modifier to what you seek is the Solidify Modifier. One reason it's not called the Extrude Modifier is because it does a lot more than a simple extrude. For instance it can extrude in two directions simultaneously by using the Offset parameter.

The normal direction of the faces determines the direction of the new thickness .


The logic bricks are never shared.

The BGE is not designed to do that (unfortunately).

In your situation it is not a big deal.

Equal objects

You can get equal objects (inclusive the same logic), by creating a group (with the sphere). Place the group object in another layer, scene or blend file.

Then create instances of the group within your level scene. Instances share everything of the group object. This includes logic.

Dynamically created

Place an instance at a hidden layer. Dynamically add copies of that instance via Edit Object Actuator (Add mode) or via Python.

This will even work in conjunction with already placed instances.

Dynamically created copies.

Place the sphere with logic at a hidden layer. Dynamically add copies of that object via Edit Object Actuator (Add mode) or via Python.


You will have notice, that connecting a more dense edge loop to an edge loop with less vertices will fail.

The solution is to use intermediate faces inbetween, translating the vertex count to a higher one and vice versa.

The resulting quads will subdivide well and work with deformations.

If the area won't deform or is planar (not the case with rounded/concave/convex surfaces), there is no reason not to use triangles.

The topology guides page has many useful tutorials including Optimal Edge Flow Loop Reduction featuring this visualization.


Select the mesh that you want to deform and go to the object data properties menu:

Then you can change the viewport mode to weigth paint in the upper left corner:

Now you can select the bone how misbehaves in the bottom right under the vertex groups
and paint over it a weight of 1 means that the movement of the bone Influences the mesh 100 % and a weight of 0 means that it doesn't influences it.


This could be happening because there is no geometry to block the light.
At 12AM, the sun is below the horizon, so the Earth should cast a large shadow on the city. In your case, however, there is no geometry to block this light, and so the sun is able to shine on your tower from below.
You could create a huge plane at z=0 to emulate the Earth's shadow. Alternatively, as you suggested, you can animate the sun's strength to make it dark at night.


Animation Nodes: How to shoot in text like bullets

Here the simplest example that I can create:

Create a loop with object iterator:

when you can add a "Invoke subprogram" node

Put here Separate Text Object. It will breake apart your text and in loop we will transform text letters one by one

Next, add animate Matrix node. This node will create a transition beetween some object (I created an empty), end each letter, that we grab from loop. To get transform matrixes, use Object ID Key node (to get initial transforms of letters) and Object Matrix Input to get empty's position and scale.

In animation node you can set duration of animation of each letter an setup interpolation.

Next, it's need to add time info node to set time to animate node.

To give each letter offset in time add 2 Math nodes. One to multiply Index with offset in frames, second - to add this offset to time:

and finally it's need to apply this transform matrix to the object, use Object Matrix Output Node:

Don't forget to connect "object" to Initial Transforms and Object Output!


Why is it the body clipping through shinkwrapped shirt?


Wouldn't it be a simple light problem...

If your lights are not setup wright as you want your scene to be lit, then you have nothing to bake since the texture you already have...I guess what you want is to have the object lighten as it would be if you put some dynamic lighting in Unity...


Why are some of my command line arguments being ignored?

Blender doesn't get to read any of the arguments after -f 1, as per the manual:

Note
Arguments are executed in the order they are given!
The following command will not work, since the output and extension are set after Blender is told to render:
blender -b file.blend -a -x 1 -o //render
The following command will behave as expected:
blender -b file.blend -x 1 -o //render -a
Always position -f or -a as the last arguments.


How do I "shift select" from object A to object B in outliner?

You can border select (B and  LMB drag) the items. If you want to select the in the 3D View as well, do a  RMB click and choose Select.


vertices are not selected properly, and i cant recalculate normals

Maybe what you're talking about is only a problem of mesh display: In the 3D View, press N to display the right panel, then in the Mesh Display panel, enable Faces, Edges and Crease as it is supposed by default? In 2.8 it will be in the header menu > Viewport Overlays panel.


How do I toggle an objects visibility in blender game engine?

This is very easy to do. All you need is a Boolean property to be toggled, and when that property is true, the visibility will be true, and when that property is false the visibility will be false. In this case we are using NameOfProp as the name for the Boolean property, but of course it could be anything.

A working example can be found here.


You need to limit the IK movement for the bones. The parameters are found under the bone tab. Check the limit option for the proper axis.

The line signifies where the bone(s) will go to accommodate the IK and will change when you change the degrees. Set it where ever you like.


You can enable "parents" in side bar Tool>Options to affect parents only.

This feature has been added in 2.81 release.


select all you need to duplicate
press copy
and then place the marker of the timeline where you want to paste
them and press paste


Creating Trees and Grass for unity ? How to add alpha layer to Vertex Colors?

If you use one of the recent nightly builds of blender

you can use the Blender Vertex Color Master Addon to get access to alpha channel.

From my quick experiments, the FBX exporter supports vertex colors. They show up in Unity. I couldn't text the animation because you didn't mention what shader you were using.


Translucent polyurethane gradient material node setup

I suspect all colors are the same, but what changes is the transparency and maybe the roughness. That is the data that would be useful to reproduce the material accurately.
In any case, the basic setup n cycles would be a glass shader, where you can control the roughness and a combination of volume absorption, for the color, and volume scatter for translucency.

Hex codes for color are not very useful, as they are meant for sRGB display referred images displayed on a monitor, and blender does not work that way. The same color can look very different depending on the lights and surrounding elements.


How can I do a monitoring/guard CCTV camera effect with blender?

If you are trying to achieve this effect on the right:

Use the compositor and distort the source image with a Lens Distortion Node in projector mode. This can make it appear like a fisheye lens. Security cameras have a wide field of view. You could add horizontal lines to simulate an old tube monitor screen. Use a wood texture node and scale the x axis to 0 and the y or vertical axis to a very large value, then multiply it with the source, after distortion.

Also security or guard cameras operate in low light so you could remove the color with a  Hue Saturation Value node.

For extra value you could add glare to the source image to blow out highlites and make a slightly blurry image, as these cameras often have poor optics. If you are making this effect in 3D I would still suggest using the compositor.


Most likely your curves need cleanup.
Diagnosis
You mentioned joining all objects after import, make sure all segments are closed curves, not separate lose segments inside one bezier object.
I would advise checking for any loose vertices, and more importantly overlapping segments, which are the most likely to cause the artifacts similar to your screenshot. Besides that very tightly close vertices, very short segments, and mostly very sharp angles tend to cause problems with beveling.
Illustrator often adds filters and effects (like drop shadows, outlines, or contours) that when converted to SVG become loose curves overlapping the original shape that often cause issues. Make sure to disable or exclude them before exporting, or cleanup afterwards
In your case the most likely culprit is the the font objects. Check the text part of your logo, fonts are often sloppily designed or of low quality, or simply not prepared for 3D modeling and contain overlapping or very close together vertex which can cause problems.
Cleanup
To clean up the curves the best method I could think of consists of selecting one vertex belonging to a text character; make sure you select the right one as there are often several overlapping. Blender highlights the whole spline that vertex belongs to with a different color so make sure you are not selecting a duplicate by checking if the whole character is marked with a different color (as opposed to marking only the single vertex you select).
Then proceed to select all linked vertex by pressing Ctrl+L making it easy to hide them with H
You are then left only with the loose or duplicated vertex visible which can easily be discarded by deleting

Anyway here is the clean file, problems were as suspected the font objects


How do I link constraint data between objects?

Select object/-s without constraint/-s first, object with them last, in Object > Constraints menu choose Copy Constraints To Selected Objects.


reseting rest pose is offsetting my armature and model

First of all in pose mode pose your character where you want to be the new rest pose, then select the mesh and apply the armature modifier, then select the armature and, in pose mode, apply the pose as rest pose; then re-parent your mesh to the armature.


Concentric circles evenly spaced in UV mode

ok the answer was pretty hard to find :P so what you basically wana do is to have a uv consist of concentric circles .This could be done if you select all the inner rings except the vertice at the mid of the concentric uv map and smooth them.But this can't be done in blender..... So what I did was to create 2 shape keys a key with the original mesh and an other one in which I smooth out all the inner rings (except the vertice in the center of the mesh).Then Uv unwram it and change the shape key value and you got it ! (I will upload a blend file with an exaple)
Also be sure to set the options so you achieve maximum smoothness

Edit: If you have many edje rings and dont want to select them by hand you can do
this:

So what you can do to select the rings is:Create a new shape key and transform your mesh similar to mines*(orange arrow) (note the red circle options) .Then do the options that are pointed with pink (you should change to ejde select mode purple) and after you click the option that the pink arrow is pointing you will have ALL the edje rings selected.

*What I did was to grab the midle vertice and pull it up


V2.79 - What are the new numpad keyboard shortcuts for changing camera view?

Press CTRLAltU to open User Preferences
Navigate to Input tab and change the keyboard preset back to Blender.

Also, you can select the preset directly from splash screen:


Actually I recalled another option called Knife Project.
In Edit mode of the cube remove the top face like this:

In Object mode select cube first and sphere second.

Then go to edit mode. Select all. Make top orthographic view and use Knife project operation from Mesh menu.

Check Cut trough box

Now you can delete your cube and when you go to edit mode with your sphere you can see faces were intersected. So you can select them separately and assign another material.

Hope it helps!


"Cannot Execute Boolean Operation" on a subdivided mesh

After some tries I've found a way to do it:

Select your curve, go in Edit mode, select all and W > Remove Doubles. You must have duplicated some vertices somehow, that's what causes your problem. Now you could apply your Boolean but still, you won't get a good result, so wait a bit.
To simplify your topology you can also do a X > Limited Dissolve.
Now, select your shield and apply the Subsurf and the Solidify modifier.
Then apply the Boolean modifier, it will give a correct result.


Text turns into squares in BGE, text not visible

It looks like the background object is covering the text.

You need some distance between the text and it's background.


How do I select one of two imported models?

rebooted my system and when i got it back up, it was working fine.


Volumetric Cube catching Torus Light
Is this what you are looking for?

Cube with Principled Volume Shader
(Density 0.1 / Anisotropy 0.95)
Torus with Emission Shader
(Properties editor > Object > Visibility > Ray Visibility > Camera OFF)

So what you see is only light rays catching on Volumetric

Something more colourful ... Torus with Noise texture and Displacement Modifier.


If you used the current version of Blender(2.83.4 at the time of writing) you would not have such an issue. In 2.79 this operation used to not work correctly with Individual Origins selected as pivot point for transform operations. Select another to fix this:


The solution to this is actually quite simple:

You cannot have any errors in your python scripts/modules, else the Standalone players animation will not run, it just sits there, making you feel sad inside.


How can I join these two meshs together?

This can be done using the Pivot Point, Snapping, and View Transforms.

We start with the honeycomb, and the target mesh in random positions (the line of green faces are the target faces):

Next, we want to do a little setup.

Set the Pivot Point to cursor, and set the snapping to vertex, and change the type from closest to active.

Note: You don't need to enable snapping, when you want to use it simply hold down Ctrl while doing a transform.

The first step is going to be getting one corner of our honey comb to match up with one corner or our target face

to do this, select the honey comb, and then Shift select on vertex along its one of the outer edges so it appear white:

Now using G-Ctrl, move the mesh to align with one corner of the target:

Next, select one of those two vertices, and use Shift-S>Cursor Two Select to bring the cursor to that vertex. Now if you use R to rotate, you can see that the mesh pivots around that point.

In order to make this a little less visually confusing, free hand rotate the mesh around the cursor until it is roughly in the right place. This doesn't have to be exact.

Next select a face along the target row of faces:

and then hit Shift-Numpad 7. *Whoosh* you world has been turned upside down.

What has happened is that the view port as been aligned to the face. We can now use R to rotate around the view port axis, and snap our mesh into place along that axis (carefully note which vertex is active):

Select that face again, and this time use Shift-Numpad 1 to go into a view that is aligned to the front of the face.

Repeat the similar steps as above:

Finally, the honey comb now lines up along the back of the line of faces, however, it is still at an angle. TO fix this last one, select one of the faces along the honey comb that runs paralleled to the line of faces:

Try Shift-Numpad 1, or 3, until you get a profile view, and then snap into place:

Your honey comb is now aligned.

Note: I used View Transforms for this example. I was originally going to use Transform Orientations, but realized that they were needlessly complex. However, if you do lots of this kind of stuff, they are worth learning about.


At the top of the bit that sticks out you have another face extending out at a 90 degree angle. The Solidify modifier is intersecting itself right there and making things go strange.
If you remove that overhang, switch the modifier to Simple, and enable Even Thickness you will get a better result.


As a beginner myself, I think the best way to learn blender is by trying to model something you find interesting. That way, you're going to know what you want to do, and then know what tutorial you should search on the internet.

Because only following tutorial from chapter 1 to end is going to be boring, if you don't know what you want to make or project based.

Just try to model something, and when you don't know how to do what you want to do, google it. I've come pretty far compared to when I was starting by using this method.


I know it's a late reply, but I think I can help, if I understand correctly.

You can use keyframes on fluid simulations.  The best way to slow down the simulation is to set keyframes in the "Speed" field.

You will have to set the keyframes and then rebake the fluid simulation so they can be applied, this can be annoying if you are using a large domain and/or high resolution to the simulation as it can take a long time to bake and rebake till its right, so it's better to bake it with a small domain and low resolution so that you can quickly check to see if the fluid is behaving the way you want, then crank-up the domain size/resolution for your final render.


How to divide a circle into slices for each side

There are several approaches.

Adding rings

If you have a circle that is a triangle fan and you want to give it rings, just Circle Select C the edges that make up the "spokes" of the circle, Esc out of Circle Selection, and Subdivide W > "Subdivide".

In the Operator Panel on the left you can adjust the number of subdivisions.

Creating a triangle fan

If you don't yet have a triangle fan and need to create one, select the edge loop of your circle, Extrude E, then Scale S inward. Type "0" to scale in to the absolute center, Enter to commit. Remove doubles W > "Remove Doubles".

Note that the face normals may not be pointing in the direction you want. In the GIF above this is evident from the dark shading. You can remedy this by selecting the faces of your circle and pressing W > "Flip Normals".

Starting with a triangle fan

When you create your circle there is an option for Fill Type. Set it to Triangle Fan and you will already have a circle made up of tris.

Insetting

A less common approach, but good to know about.

If you have a circle that is an n-gon, with the face selected, press I and you can inset it inward. Finally, Scale S in to "0" and Remove Doubles W > "Remove Doubles".

Beveling the center vertex

If you're starting from a triangle fan, one more approach you can take is to bevel the center vertex to create the edge ring necessary to perform a Loop Cut. If you type in a near-zero value the 8 resulting center verts will be right on top of each other and you can easily patch the center hole later using Remove Doubles.


Translucent material (a sheet of paper) with image texture?

You can use the transmission input on the principled shader in cycles for this.
To distinguish the one side from the other you can use the input node Geometry Backfacing. Adjust the ramp node to get the thickness you are looking for.

If you need to color your translucency this could be a way to solve it. Allowing some of the light from the backside pass by adding in a Translucent shader and then mix this. By using a mix node the energy from the incoming light will be handled more correctly than with an add node.

I hope that the Principled shader will get support for color transmission in the future.


I think you should apply all the modifiers in the properties panel before exporting (starting from the upper, down to the lower).

If you want to export also the armature, after you applied the armature modifier to the mesh, go to pose mode and "apply pose as rest pose". Notice that this operation will destroy your animation (except for the last frame, that becomes the new "rest pose".


I eventually found a way. It doesn't really feel like a proper solution but it works. In Cycles, you have to switch to material mode and you will then be able to see all layers. But the problem is that your object will interact with the lights so you have to also temporarily make your material shadeless.


The problem was in the construction of the mesh. I added loop cuts to each of the lines and then bended it using the simple deform modifier.

Final result


In Unity vertex weights are normalized, meaning the sum of all weights for each vertex has to be 1. (It might also be the blender converter/exporter that does that, I don't know)

So if the 0.1 weight is the only weight applied, it will become 1.
You should add 0.9 weight to another bone (probably the root-bone) to fix it.


Handler Function doesn't update Text Object in 3d_View

An issue of scope.
As mentioned in a prior answer.  Defining frame current outside the handler sets it to what the current frame was when question script above is run and the handler is registered.
If you want current frame when the handler is run
def frame_change(scene):
    frame_end = 200
    frame_current = scene.frame_current
    print(frame_current ," = script start")

secondly recommend don't scope an object outside the handler, instead within the handler
ob = scene.objects.get("Text")
if ob:
    # it exists do something to it.

Also don't mix context with handlers. Every chance it will not work as expected, especially when rendering.
Related.
Handler-script updates in viewport but not in render
This should work in 2.7
Notice for 2.7x use frame change pre, for 2.9 use frame change post.
Notice the use of the div operator
int(frame_current) // 10

to set on each frame, otherwise will not set properly until a 10th frame using the modulus == 0 operator.
import bpy
from bpy.app  import handlers

from bpy.app.handlers import persistent
@persistent
def frame_change(scene):
    frame_current = scene.frame_current
    frame_end = 200
    obj_active = scene.objects.get("Text")
    print(frame_current ," = script start")
    if obj_active is None:
        return # no font object named "Text"
    if frame_current <= frame_end:
        obj_active.data.body = str(int(frame_current) // 10)
        print(frame_current , int(frame_current) // 10)
    print(frame_current ," = script end")

def register():
    handlers.frame_change_pre.clear()   # use when testing will burn others
    handlers.frame_change_pre.append(frame_change)

def unregister():
    handlers.frame_change_pre.remove(frame_change)

if __name__ == "__main__":
    register()


Image texture showing up in texture mode but not render

You have connected the image texture directly to the surface output, but it needs to be connected to the Color input of a shader, for example a diffuse, like this.

World map courtesy of NASA, downloadable in several pixel resolutions from NASA Visible Earth

Below is the same material as it appears in the node editor, to make it clearer how to connect them.

In case your texture has an alpha channel, that doesn't get passed through the Color sockets. Instead it's passed separately through the Alpha socket. This can be used to mix multiple shaders, depending on the alpha channel, but to simply use it for transparency, connect it like this.

The logic here is, that when the alpha is 1.0 (i.e. fully opaque), the lower Shader socket to the Mix shader is passed to the material, and when the alpha is 0.0 (i.e. fully transparent), the upper Shader socket gets passed to the material, and anything in between, causes a corrsesponding mix of the two to get passed to the material.


Assigning vertex groups to bones precisely

Fast and easy way to do it is in edit mode, select the part of the mesh that you want to be effected buy one bone, then in vertex groups select the group of related bone and assign weight with value of 1.

Then select other other vertex group and hit remove button.

Then repeat the same process on the other part of the mesh assigning or removing weight that you want to be associated with that part of the mesh.


To copy an object you have to be in Object mode, right click on the object that you want to copy and the press Shift + D to duplicate it first.

The duplicate will be in grab mode so right click to get out of grab mode without changing its location.

The object will still be selected but if it isn't, you can look in the Outliner for it. It will have the original object name followed by a number indicating that is a duplicate such as Object.001.

You then press M to bring up the layer move popup menu and click the button for the layer that you want to move it to or alternatively type the number corresponding to the layer.


How do I remove the numbers displayed for lines on a mesh when you "A" a mesh?

Nvm, tinkered and realized had to deselect checkboxes for Edge/Face info under "N."


Move items equally from each other/centre/angles?

I think Object\Transform\Push/Pull is what you are looking for.
Select all objects in Object Mode and use Object\Transform\Push/Pull from the menu. As the name suggests it will push or pull from the center of all objects.

Based on your comment I assume what you are really looking for is an circular array. Here's a good tutorial for it: https://www.youtube.com/watch?v=bLGYsd4lEjY
Once you set it up you can move your object in edit mode (so the origin stays at the same position) to push/pull the array from the center.


What does "self lit" mean, and why is it a good thing?

It refers to models that already have the lights prebaked using lightmaps or pre-render all the model and bake it into a texture. Both are useful for real-time visualization of static scenes, since it can show photorrealistic results without have to render everything everytime. You can get more information about in the links below:

Lightmap: https://en.wikipedia.org/wiki/Lightmap

Baking: https://www.youtube.com/watch?v=sB09T--_ZvU


Objects may appear illuminated, if ...

they are illuminated by lamp objects
they are illuminated by mesh lights with emission shaders
they are emitting light completely or partially, if they have an emission shader
the wrongheaded use of an Add Shader in a material
they are illuminated by the world (background shader)
ambient occlusion is activated

The Ambient Occlusion is activated in your scene.
Uncheck Ambient Occlusion to disable it.
It is found under the World section of the Properties Panel.
Also make sure no light emitting objects are hidden by pressing AltH to unhide all objects.


Lengthen an edge infinitely (a.k.a. vanishing point)

Since your screen resolution is far from infinite, moving points far away will quickly reach the pixel size of your display. Starting with a 2m default cube, extruding an edge back 5000m should be plenty enough to simulate infinity and have them join at a subpixel level. Before doing this, don't forget to increase the Clip End limit of your viewport of camera.

Here is a simple way to do it in the view port:


Camera Tracking - How to Reconstruct LocRotScale Marker To Empty?

Select your empty. Press F3 or spacebar for "SEARCH", type: "bake animation". Select Rotation, Scaling, etc.. Leave everything at default. Press OK.
In a new workspace window, switch to GRAPH EDITOR (shift F6). Select in your outliner the recently baked empty (if it's not already selected), you should open the eye icion in the graph editor, and find the channels you're interested in (rotationXYZ, and ScaleXYZ) now they should contain baked data.

From your question is not cleared if you did the tracking using blender tools of if you're importing it from another software. But at leas if you're inside blender, the previous described procedure should get data into your empty to track or follow.


Python: Enter or leave "User Perspective (local)"

Check the menu in the 3D view, and right-click the "View Global/Local" menu item. You can then choose "Copy Python Command". It'll give you bpy.ops.view3d.localview(), which is the operator that is executed when you click on that menu item.

Note that it does require a context of a 3D view, so if you try to execute that command as-is in the Python console, it'll refuse (your Python console doesn't have Global/Local view). However, if you execute it as part of your own operator running in a 3D view, it'll be fine. In that case you can also simply use context.area.spaces.active.local_view instead of iterating over all areas in the current screen.


Your issue comes from your object design : the cylinder and the circle should be in a single object + the circle should have a thickness + The circle should be an extrusion of a ring of the cylinder.

The idea is to create the cylinder, to add a loop on this cylinder and to extrude this loop to create the cicle.

Here is a full how to :

Create a new project
Delete the cube
Add a cylinder : press Shift + A then select Mesh and Cylinder
Enter in edit mode (TAB)
Press S then Z to enable Z scrolling
Move the mouse to increase the hight of the cylinder.
Press ENTER to validate.
Move the mouse cursor in the center of the cylinder
Press CTRL + R to add a loop cut : a pink horizontal circle should appear at the middle of the cylinder like this :

Scroll up the middle mouse button to have 2 pink circles like this :

Press the left mouse button
Move the mouse up to place the new ring
Press the left mouse button to validate
Enable the Face select mode (CTRL + TAB and select Faces)
move the mouse cursor on a vertical edge of the middle ring you have just created
Press ALT + RMB : this ring should be selected (in orange) like this :

Press E to extrude this ring and press LMB to validate immediatly (without moving the mouse)
Press S to scall the ring and Shift + Z to lock Z scalling
Move your mouse to increase the diameter of the ring like this :

Press LMB to validate

To enable Freestyle :

exit Edit Mode (TAB)
in the Render panel, enable the Freestyle option
launch render (F12)

Here is the result (after adding materials and reducing the circle thickness :


Is there anything like Meshmixer's “Attract Tool” in Blender?

This looks like a combination of Vertex Weights and a Shrinkwrap modifier.

On the object to be deformed, in its Data tab, Vertex Groups panel,
create a vertex group .. call it something like 'Shrinkwrap'
Assign vertices to it. Vertices can have a weight between 0 and 1 in the group, or not belong to the group at all.
One approach would be to assign only the vertices you want to deform
to the group, with weight 0....
Assign a Shrinkwrap modifier to the object, targeted on the object you want to shrink to,and affecting only the Vertex Group you've created.
Now in Weight Paint mode, you can hit 'Restrict' in the Tool tab > Options panel to protect vertices outside the Vertex Group from being affected..
.. and paint weight into the group. As you paint, the vertices will be drawn to the target.

There are numerous options .. in the modifier, and in the way you paint or assign weights to the vertices, (for instance, you can forget painting, and assign weights in Edit Mode) so really, it would be good to have a mooch in the docs and play with them, and if you get stuck and there's a particular way you'd like the tool-combination to behave, come back with a comment, and we can be more specific.


I had a similar problem and am in a similar situation to you (in that I'm relatively new). I believe the solution ended up being checking where I shade smooth and manually changing the geometry so I didn't get any weird artifacts. If I remember correctly, the issue is with the two meshes having different geometry, so blender struggles to match them in a pleasing way.
Hope this helps


Why can I see though my Mesh (even in renders)?

The problem was blend mode , the blend mode was set to alpha blend , when i changed it to alpha hashed , it got solved


Animation: How to bake physics to export to Sketchfab

Select the toruses and the rig then export it to fbx. In the fbx exporter "Main" tab (lower left corner) check in "Selected objects". In the "Animation" tab disable "All actions" and "NLA Strips".


Python script to extrude with scale restriction

thanks batFINGER, your suggestion worked like a charm.  this is it:

    bpy.ops.object.mode_set(mode = 'EDIT')
    bpy.ops.mesh.extrude_region_move(MESH_OT_extrude_region={"mirror":False}, ...snip...
    bpy.ops.transform.resize(value=(1.5, 1.5, 1), constraint_axis=(False, False, False))
    bpy.ops.object.mode_set(mode = 'OBJECT')

with some magic numbers.


Is there a way to simulate water balloon physics in Blender?

Do you want a physically accurate simulation ? Or just something that looks like a water ballon ?

If you want something that simulates the look of a water ballon I would suggest looking at soft body but If you want to go in depth, You would need to put a fluid simulation inside a soft body or a cloth simulation ( but you will need a pretty buffed up computer for that ).


Getting noise texture to flow continuously across multiple objects

One way of doing it is to add an empty to the scene and using it as a texture coordinates provider in the material. My guess is that you have something like this for now:

So after adding an empty to the scene and using it in the texture coordinates node, you'll get this:

Hope this helps!


Blender 2.8 Beta - Unknown Rectangle when camera is selected

That is the Render Border. When rendered shading is active, the render will be constrained to that portion of the screen. You can disable it with CtrlAltB, or you can enable and/or draw a new one with CtrlB.

See Render Border's related check boxes - How do they work? for a more complete overview of its functionality.


How can I make the camera taller in the Blender Game engine?

By making your camera taller do you mean to change the resolution? Your character and your camera should never be the same object. Make a cube (this will be your character), and parent the camera to it. The camera should be set to no collision and the box to dynamic. You can change the shape of the cube if you want the character to be taller. Or if you just want the camera to be higher up you could just move it up in the Z-axis.
If you are meaning resolution then you can simply adjust it in the Output tab under dimensions.


Use a Particle System
You can easily do it with the built in tools.

Start by creating the array, be sure to enable the merge option.
Create a Hair type particle system, set the number of particles equal to your array repetitions and the render type to collection and choose "pick random".
Enable the advanced options and make sure to "Use Modifier Stack" (option enabled). Disable Random Order and set 1 Particle per face.

BAM! Done.
Now it's only a matter of adjusting the rotation and the size of your instances.

You can inspect my file with the proper values for size and rotation here:


Your probably looking for bpy.context.selected_bones

Or ... selected_editable_bones


How do I make bevel equal on both sides of the edge?

It's because your object has non-uniform scale.

First, go to the object mode. Then press Ctrl + A -> Rotation & scale (object-apply)

Then try again


It's possible when Surface> NURBS Curves or NURBS Circles are used. Add and select them all and join with Ctrl+J in Object Mode. Next go to Edit Mode and press A followed by F. In edit mode you can stretch your shape to the endpoints and edit it. Once done,you may use Alt+C to convert object to mesh. NB: the number of control points must be the same for each element.


I want to add keyframes for a "Dynamic Paint" modifier setting "Alpha" Using Python

I've found that you can keyframes in many different locations along the data_path, not just at the object level.
This conversation clarified that a bit:
Adding Keyframes to Evaluation-Time Using Python
using-python
some_obj.modifiers["Dynamic Paint"].brush_settings.paint_alpha = 0
some_obj.modifiers["Dynamic Paint"].brush_settings.keyframe_insert(data_path="paint_alpha", frame=150)
some_obj.modifiers["Dynamic Paint"].brush_settings.paint_alpha = 1
some_obj.modifiers["Dynamic Paint"].brush_settings.keyframe_insert(data_path="paint_alpha", frame=190)


Selected to Active texture baking incorrect colors + Blurry texture

I fixed the incorrect color baking problem by unticking "Interpolation" and "Mip Map" from the original's "Image Sampling" panel, and then baked the texture. As I'm using the model in Unity, I fixed the blurry texture by setting some values in Unity's inspector panel.


cloth simulation, cloth(plane) collide at center of of the cube instead of at the surface

This can be because if many problems you should try these:-
Make sure that all modifiers on cube are applied and that on plane the cloth simulator is the last modifier or is only equipped with cloth modifier.
Also increase permeability of collision modifier on the cube as 1 and check that it is setted to volume rather than being on object origin.
Also try deleting and again adding the cube in the file it is not working.
If it still don't work then you may even delete the plane and add it again in your scene.


Why some parts of the object don't move with the armature?

The first reference picture looks like some vertices have no vertex groups (weightpaint) assigned.
You can fix it by selecting the responsible vertex group in the Properties Tab -> Object Data Properties (the green triangle icon), switch to Weightpaint Mode and use some blur brush on those lacking parts.
This helped me a lot so far.


Access color of a point given the 3D position (on the surface of a polygon)

Some indications for a way to do that (maybe there are other possibilities... I'd be interested if some other answer could offer something more simple).

From the comments below the question, I assume the following entry parameters:

A mesh
A ray cast point 'V' on the mesh, so you also have the corresponding polygon index 'P' (considering you are using BVHTree from the mathutils module)
A UV map
A texture

First thing: at some point, you'll need to match V position on P to the V' position on the UV map part where P correspond to.
That can be done using barycentric_transform (function which can be found in mathutils.geometry), but a triangle is needed (as we need all to be convex).
This means that you need to work on a triangulated mesh (you could also triangulate on the fly, but I don' know how to do it).

So the overall process can be the following:

Get your mesh
Triangulate it
Ray cast and obtain V and P (a triangle)
Find the UV map part P' corresponding to P
Calculate V' using barycentric_transform
Remap V' on the texture

Some indications for all that using bpy and bmesh modules

Get your mesh

Snippet

import bpy
obj = bpy.data.object['your mesh name']

Triangulate it

Snippet

import bpy
import bmesh
def TriangulateMesh( obj ):
    bm = bmesh.new()
    bm.from_mesh( obj.data )
    bmesh.ops.triangulate( bm, faces=bm.faces[:] )
    bm.to_mesh( obj.data )
    bm.free()

Eventually, work on a copy:

def CopyMesh( obj ):
    copy = obj.copy()
    copy.data = obj.data.copy()
    bpy.context.scene.objects.link( copy )
    return copy

Ray cast

Snippet

from mathutils.bvhtree import BVHTree
... some code and at the end:
location, normal, index, distance = bvh.ray_cast( ... your parameters )

index here is P.

Find the UV map part corresponding to P

Get 3D vertices indices

verticesIndices = obj.data.polygons[P].vertices

P vertices coordinates in 3D space

p1, p2, p3 = [obj.data.vertices[verticesIndices[i]].co for i in range(3)]

P UV map vertices indices are found in:

uvMapIndices = obj.data.polygons[P].loop_indices

The UV map

uvMap = obj.data.uv_layers['your uv map name']

The coordinates of P vertices in the UV map space:

uv1, uv2, uv3 = [uvMap.data[uvMapIndices[i]].uv for i in range(3)]

Calculate V' using barycentric_transform

V' is given by (make uv1, 2 and 3 as 3D vectors before):

V' = barycentric_transform( V, p1, p2, p3, uv1, uv2, uv3 )

Remap V' on the texture

Get the texture, the pixels and texture dimensions:

image = bpy.data.images['your texture name']
pixels = list( image.pixels ) #Faster than accessible image.pixels[x] each time
width = image.size[0]
height = image.size[1]

From V', get x and y. These values as give as if the image size was (1, 1). So you need to rescale and modulo x and y, then reach the corresponding image color using 'pixels' (which is a linear byte array of individual color components RGBA).


The Blender Manual is right. There is a viewer node under Output, but it's in the Composite Node Editor. I bet you are looking in the Material Node Editor.

To get one in the Material Node Editor, you have to activate the Node Wrangler add-on, then you can use Ctrl+Shift+LMB to create a temporary Viewer Node.


For render - ensure Vertex Color name matches with the Name in Atribute node field.
For export -

PLY - exporter works for me (vertex color option is enabled by default)
ABC - exporter can also store vertex color data, just enable it in export options
OBJ - exporter doesn't have this feature. So you can export as PLY or ABC and use free app Meshlab to export as OBJ with vertex color.

Alternatively you can Bake vertex color into texture.


I did 3d model at work, did save .blend file to cloud... textures missing at home

Go to File menu / External Datas / Find missing files, then select the right folder on your computer.
A way to avoid this is to check "Automatically pack into .blend" (in File / External Data) before saving ; this will include every texture into the blend file.
Another (better?) way is to use Relative Path data and keep the same folder structure. I usually don't "move" a blend alone, but his entire folder, including his textures/assets/etc subfolders.


It is pretty much the same. Go to the world settings. And then under surface you can change the strength. Of course you
also can change the color of the environment there:


This is because some objects are not set to be rendered:
In layer.001:

In layer.002:


First tried to find out if it was an interior face, but it is only an edge I could delete. However I need the extra geometry for shading purposes.
Then I was pointed to Non-manifold fixes from Gleb in a Bendernation post and with the addon '3D print toolbox' I found a way to fix the geometry by cleaning up 'distorted' faces. Some extra geometry was added and the result is that the orange line isn't visible anymore.


Annoying uv or pbr map After sending project

This can happen when the Normal Map is set to sRGB (the values are then gamma corrected).
Make sure your client has it set to Non-Color.
It works just fine for me, Blender 2.83.


Those in the image definitely look modeled, not some sort of bump map or normal map trick, but both techniques can be used or even combined to achieve desired effect.

Deciding whether to model them or use some trick like normal maps or bump mapping/parallax mapping will largely depend on the purposed of your model , where or what for it will be used, and the limitations of that system.

If you are doing regular rendering with cycles/blender internal and have no/very little constraints in terms of polygon counts you should definitely consider modeling them for more realistic accurate results.

If your computer is slow or can't handle the details, or if they are not the main focus of the artwork and will be very far away/out of view you may consider using some sort of simplification like a bump map or a normal map to simulate the effect.

You can combine both techniques (modeling + normals) to obtain even further detailed model.

You may also choose displacement maps to generate actual geometry bumps from an image texture, at the expense of higher polygon counts. These are generally more suited for organic or irregular models.

If you are planning using it in some sort of game engine or real time visualization where complexity is a limiting factor you may bake the details into normal maps or bump maps from a high poly to a low poly version of the model

Either way, if you want to do it very accurately, you will probably have to model the gribbles in 3D yourself anyway, so you can use it later to bake it to the lower poly version.

As to the modeling part they seem to be simple boxes repeated across the surface, nothing too special about them. Use modifiers like Array for repetition, or the Shrink Wrap to place "2D" shapes across the larger surfaces then give them volume with a Solidify modifier. You can keep the greebles as a separate object parented to the main mesh so as to not increase the polygon counts/triangulation of the original, and still be able to turn them off or reuse them elsewhere with ease.


How to unparent children and keep them (where they are)?

Select the circles, go to Object > Apply > Make Instances Real or press F3 and type "Make instances real"


AttributeError: 'tuple' object has no attribute 'append'
You explicitly break your loop.


How to batch rename materials or auto assign them to the name of the texture file

Using blender internal, the textures can be found in bpy.data.textures. By looping through this you can easily match the texture name to the image it has.

import bpy

for tex in bpy.data.textures:
    if tex.type == 'IMAGE':
        tex.name = tex.image.name

Usually the image name is its filename without extension, if you have image names with extensions, you can use os.path.splitext to remove the extension.

tex.name = os.path.splitext(tex.image.name)[0]


Reset multiple shape key values back to 0?

Yes, just click on the X button near the value field.

2.7:

and 2.8:


How to choose 1 vertex, change its coordinates, and have its mesh move along intact with it?

If you move the object in Object Mode, it moves all at once, but if you want to use Edit Mode for whatever reason, you could:

Turn on Proportional Editing (either press O or select it at the bottom of the 3D view) move the vertex by using the 'Grab Tool' (G) and then typing In the coordinates into the 'options panel' of the Toolshelf (T)
Once the vertex is where you want it to be, scroll down in the same
panel to the proportional editing section, and increase the
'Proportional Size' until the entire mesh moves to the desired location


Trouble exporting in correct file format

Blender will never generate text files for images, it cannot do that. This is a user error and improper configuration in blender or the OS

What might be happening is that the option to add the proper extension to the file name has been disabled and the OS does not know what kind of file it is dealing with. If you are using windows the computer cannot guess what to do with files that do not have the 3 letter extension at the end of the file name (like *.jpg)

Options to fix the issue: on the already rendered images just add the proper extension to the file for exmaple: image01.jpg (if the image is a jpg file).

For future renders enable the File extensions box on the output settings.

If your OS is still trying to open files with the .jpg extension as text, then you need to configure it to use a different deafult app. In which case it is not an issue with blender and will require you to learn how to use your computer and set the default app to open image files.


Learn Blender 2.7 now or wait for the 2.8 Beta release?

Learn now, and it's ok to start with 2.8

Blender 2.8 makes many changes to some fundamental aspects of how we interact with the software and with each workflow. Most notably: layers are gone and the objects are organised differently; using workspaces for different kind of tasks is now visually encouraged (with some great default workspaces!); the creation of materials is done with a new efficient LookDev mode.

Many shortcuts were changed, included commonly used ones; almost all the icons are changed too, and the interaction with the Viewport has been improved in many ways.

Since it appears that the Alpha 2 version is stable for most of the users, I'd suggest trying Blender 2.8 directly. You won't have the burden to re-learn new shortcuts and to get used to new defaults.

Just don't rely on an experimental version for anything professional, but as I understand you are just trying to pick up a new hobby/interest, and Blender 2.8 won't hurt you! Some tutorial creators have already started publishing 2.8-based videos (but 2.79 tutorials will be mostly fine too, with some effort to figure out the hotkey changes)


How to create a simple list in the UI with Python API that would display data from Python?

Ok, I've got it. But still do not fully understand.

bl_info = {
    "name": "Collection Menu",
    "author": "CoDEmanX",
    "version": (1, 0),
    "blender": (2, 65, 0),
    "location": "",
    "description": "",
    "warning": "",
    "wiki_url": "",
    "category": ""}

import bpy

coll_data = [
    ("Option A", "The first option, can be found by searching '1' as well"),
    ("Option B", "You can find this by searching for 'roflmao'"),
    ("Some text", "Some more descriptive explanation"),
    ("Blabla", "Talking stuff...")
]

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

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

    def execute(self, context):
        print("test")
        coll_data.append(("a", "b"))
        bpy.app.handlers.scene_update_pre.append(collhack)
        return {'FINISHED'}

class Actions_List(bpy.types.UIList):
    def draw_item(self, context, layout, data, item, icon, active_data, active_propname):
        if self.layout_type in {'DEFAULT', 'COMPACT'}:
            # You should always start your row layout by a label (icon + text), or a non-embossed text field,
            # this will also make the row easily selectable in the list! The later also enables ctrl-click rename.
            # We use icon_value of label, as our given icon is an integer value, not an enum ID.
            # Note "data" names should never be translated!
            split = layout.split(0.3)
            split.label(item.label)
            split.label(item.description)

        elif self.layout_type in {'GRID'}:
            pass

class MyColl(bpy.types.PropertyGroup):
    #name = bpy.props.StringProperty()
    label = bpy.props.StringProperty()
    description = bpy.props.StringProperty()

class MyScriptPanel(bpy.types.Panel):
    bl_label = "MyScript Panel"
    bl_idname = "OBJECT_PT_myscript"
    bl_space_type = 'PROPERTIES'
    bl_region_type = 'WINDOW'
    bl_context = "scene"

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

        col = context.scene.col
        idx = context.scene.col_idx

        if idx >= len(col):
            #context.scene.col_idx = len(col) - 1
            text = "(index error)"
        else:
            text = col[idx].name

        layout.template_list("Actions_List", "", context.scene, "col", context.scene, "col_idx")
        col = layout.column(align=True)
        row = col.row(align=True)
        row.operator("object.simple_operator" , text = "All")

def collhack(scene):
    bpy.app.handlers.scene_update_pre.remove(collhack)

    try:
        scene.col.clear()
    except:
        pass

    for i, (label, description) in enumerate(coll_data, 1):
        item = scene.col.add()
        item.label = label
        item.description = description
        item.name = " ".join((str(i), label, description))

def register():
    bpy.utils.register_module(__name__)
    bpy.types.Scene.col = bpy.props.CollectionProperty(type=MyColl)
    bpy.types.Scene.col_idx = bpy.props.IntProperty(default=0)

    bpy.app.handlers.scene_update_pre.append(collhack)

def unregister():
    bpy.utils.unregister_module(__name__)
    del bpy.types.Scene.col
    del bpy.types.Scene.col_idx

if __name__ == "__main__":
    register()


How to use multiple particle types in a particle system?

You will first need to select the objects you want to use, and press Ctrl+G to create a group.

Then use the Groups setting under Particle Systems > Render.

First, select the Group render type:

Then select the group you want to use:


If the "Alpha" input is in the "Base color" of the principled node:

Then it will look like this:

If you put the "Color" input in the "Base Color" output on the principled node:

Then it will have color:

-
-
Hope this helps!


Why are parts of my scene not visible after rendering?

Just got answered by Lemon, the camera icons were grayed out in the Outliner.


You need to be in Cycles to be able to see the Use Nodes button for lights


This method is working suprisingly well in EEVEE. It's fully real time (fast, very fast). In Cycles also. And it is very flexible.

Material setup

Basically it is mix between Emission and Emission Transparent shader.

I've used Normal input to drive Facing Blend value, this is for making "highlights". Color Ramp is for fine tuning intensity of those highlights. By rotating sphere inside Normal node you can achieve many interesting setups. The one from example is pointing downwards.

Fresnel is used to make a bit of an outline around object.

EEVEE

To make it work in EEVEE you need to change material Blend Mode to Alpha Blend and turn of (if you need it) Show Backface.

Cycles

For Backfacing in Cycles you can use this setup. It's not working as well as in EEVEE but it is still good.


You can get curve Bevel depth with bpy.context.object.data.bevel_depth

or set it with bpy.context.object.data.bevel_depth = 0.1 (replace 0.1 with desired value)


You can use a curve to do this. in order to make it into a tube you need to set the fill to full and raise the bevel depth and resolution. You can then animate the start value to control the end of the strip. If you need to scale up or down the ends, select a point on you curve and use Alt-S.
To animate, the start value hover over the input box and it I to add a keyframe. The navigate to the other end of your animate, set the value down/up then hit I again to add another keyframe. Keyframes can be remved with Alt-I.

The green lines in this gif were created using this technique in blender

Single image with settings

Green squiggles file:


Lock part of an object so that it doesn't scale

I created the dynamic length pipe with two objects. The first object is one unit long, only large enough to house the hole at the end. The second object it just the tube, easy to change the length, via scaling or inputting dimensions.

The way I link the two pieces, is with a Child of Constraint (scroll down to the bottom of answer).
Normal parenting would influence the scale, but with a child of constraint (CoC) each of the transform operations and channels are selectable.
Add a CoC to the hole object with the Target set to the main pipe.  Uncheck all the Scale boxes.

Blend File
You will move the tube from only the large main section. However when you duplicate it, you will need to duplicate both objects.


If what you want to do is what Nicola Sap shows, here is another way to do it, pretty close, but with the Bevel tool:


How come I need to manually correct .mtl file?

The answer is: It depends.

The .mtl file is following the specification and is therefore correct. However some viewers do not implement the specification in its entirety or may not even implement it correctly. Therefore it may be necessary to adjust the .mtl file to make it work properly. However this is not because the .mtl is wrong, but because the viewer doesn't support the Ns, Ks and illum statements.

  Ns exponent

  Specifies the specular exponent for the current material.  This defines
  the focus of the specular highlight.

  "exponent" is the value for the specular exponent.  A high exponent results in a tight, concentrated highlight.  Ns values normally range from 0 to 1000.

  Ks r g b

  The Ks statement specifies the specular reflectivity using RGB values.

  "r g b" are the values for the red, green, and blue components of the atmosphere.  The g and b arguments are optional.  If only r is  specified, then g, and b are assumed to be equal to r.  The r g b values  are normally in the range of 0.0 to 1.0.  Values outside this range  increase or decrease the relectivity accordingly.

  illum illum_#

  The "illum" statement specifies the illumination model to use in the material. Illumination models are mathematical equations that represent various material lighting and shading effects.

  "illum_#" can be a number from 0 to 10.  The illumination models are summarized below; for complete descriptions see "Illumination models" on page 5-30.

  Illumination    Properties that are turned on in the Property Editor

  0     Color on and Ambient off

  1     Color on and Ambient on

  2     Highlight on

  3     Reflection on and Ray trace on

  4     Transparency: Glass on
        Reflection: Ray trace on

  5     Reflection: Fresnel on and Ray trace on

  6     Transparency: Refraction on
        Reflection: Fresnel off and Ray trace on

  7     Transparency: Refraction on
        Reflection: Fresnel on and Ray trace on

  8     Reflection on and Ray trace off

  9     Transparency: Glass on
        Reflection: Ray trace off

  10        Casts shadows onto invisible surfaces


user preferences > Editing > Only insert needed enabled


How would you go about creating a facade like this? How do I make each element unique and texture them so it looks hyper-realistic in the end?

The distortion for the wooden planks/Bamboo poles you can create with a Displacement modifier with very low strength (0.005267). Add it after the Array modifier. Use a Musgrave texture with low size=0.03, type fBM. This gives you something like this:

You need a better wood shader than in this example so that the poles/planks don't look like "toothpicks".


part of the mesh become yellow when in sculpt mode

This is the new "Face Sets" feature, I think. It seems to be meant as an extension to the use cases currently covered by hiding and showing faces.
It does not seem to be particularly well documented, or to have much in the way of exposure in the user interface, at this point.
You probably did nothing wrong. I assume that the Boolean modifier probably automatically created two "Face Sets" corresponding to each mesh when they were joined.
To fix this problem, you can open the new "Face Sets" menu in the 3D view's Sculpt Mode header. The very last option says "Randomize Colors", and will randomly reassign each region of your mesh a new colour. You can repeat this operation until the colours of your mesh are no longer yellow. (I hope you like purple, red, blue, or green.)
Alternatively, you could also try one of the options under "Init Face Sets", or using the "Draw Face Sets" sculpting brush and holding CTRL from one area to paint over the rest of your mesh.


Pointer property

Use a simple collection property with a name and a pointer to an object

import bpy

from bpy.props import CollectionProperty, PointerProperty

class ObjCollection(bpy.types.PropertyGroup):
    object = PointerProperty(type=bpy.types.Object)

def register():
    bpy.utils.register_class(ObjCollection)
    bpy.types.Object.foo = CollectionProperty(type=ObjCollection)

if __name__ == "__main__":
    register()

I've added the foo collection to every object... now off to the python console to test, clear the objects list

>>> C.object.foo.clear()

Load up every object in scene to context objects "foo" collection

>>> for o in C.scene.objects:
...     item = C.object.foo.add()
...     item.name = o.name
...     item.object = o
...

Rename every object in scene to "Bar"

>>> for o in C.scene.objects:
...     o.name = "Bar"
...

Iterate over context object foo

>>> for o in C.object.foo:
...     o.name, o.object.name
...
('Cube', 'Bar.001')
('Lamp', 'Bar')
('Camera', 'Bar.002')

The object formerly known as "Cube" is now known as "Bar.001" etc.

If the object has been since removed then

C.object.foo["Lamp"].object is None

We know that the lamp,  "Bar" formerly named "Lamp"  has been removed.

Please note: have defined the properties on classes eg bpy.types.Object and then deal with instances eg context.object.  In your question code it appears you have monkey patched a list onto the class bpy.types.Object (the one and only...) instead of, as shown in above,  the instances of that type (many)