Your low poly and hi poly meshes are overlapping. You forgot to turn off rendering for the low poly model. Click the filter icon in the upper right of the Collections panel and choose the camera (and while you're there, the monitor icon). Deactivate the camera for that object.


Modeling a fish with curves - complication at tail

Why not give sculpting a try? You could make something close to what you want and touch up the details in sculpt...

heres a link to a video instructing how to use dynamic topology (and by extension sculpt mode)

https://www.youtube.com/watch?v=opsKPCCFbr4

docs on sculpting

http://wiki.blender.org/index.php/Doc:2.6/Manual/Modeling/Meshes/Editing/Sculpt_Mode

docs on dynamic topology

(note that this feature has been changed in 2.7, it can now be found under the header labelled "dynotopo")

http://wiki.blender.org/index.php/Dev:Ref/Release_Notes/2.66/Dynamic_Topology_Sculpting


You can Tab into Edit Mode, key A once or twice until everything is selected, key W to open the Specials menu and select Remove Doubles.


looping through splines of a bezier circle, can only find 1 spline not 4

Your object has curve data. The curve data object holds a spline collection.

In each spline there are bezier_points or points.

You have mistaken a bezier point for a spline. The spline is a continued element made up from multiple points. As a curve data object can hold multiple splines (they can be discontinued/separate), it has a spline collection.

You can access the points with the Spline Info node. However if you want to produce a variable point list, I'd suggest inserting a script node which takes in a point list and outputs the modified point list.


Usually when you import a SVG file it is extremely small (so small you cant see it). Draw a box select ("B", or choose it from the outliner) around the center of your screen and scale it up by a lot (You still may not see anything, scale it up again) after scaling two or even three times you will start to see it.

After you get it to the size you want dont forget to apply the scale (CTRL+A) "apply scale"


Imported Texture only on one side of Object

Ok, Solved the problem by unwrapping the back half of the mesh(the part were their is no texture), which is when the texture applied to the half that it was not before!


How can I create an object which masks and cuts into other objects?

Add a Boolean modifier to the cube you want to remove parts from. Set the operation to Difference and select an object that is used as volume to calculate the difference.
Then enable the Restriction Toggle for Disable in Renders (camera icon) for the same object that is used in the Boolean modifier for the Difference operation. This will hide it in the render. You can also hide it in the viewport in case you want to see the effect of the modifier right away as shown in the video at the beginning.

Once this is configured you can animate the objects. The cube will have parts removed without the other object being visible in the render.


Normal Map Baking: Does Low-Poly Mesh need to have larger volume than High-Poly?

It is a bit difficult to tell what is going on from your screenshot, however, the basic answer to your question is yes - your low poly mesh needs to enclose your high poly mesh.

Your low poly mesh needs to follow all the major shapes and features of your high poly mesh. Think of it like wrapping your high poly mesh in wrapping paper. You can't have big spikes sticking out of your wrapping paper.

The purpose of baking a high poly mesh to a low poly mesh is:

To get better topology (your low poly mesh can be created with good edge flow); and
To bake all the very fine surface detail into a normal map so that its appearance is then created by normal mapping, and not actual geometry.

The trick is therefore to have your low poly mesh follow all the major shapes and features of the mesh, while ignoring the very fine detail (as this will be baked to a normal map). Sometimes that is a bit of a judgement call, but if you keep coming back to the wrapping paper analogy (what would you wrap around with wrapping paper, and what would you just paper over), it should be OK.


Python: Selecting faces from a Material Index

import bpy
    import bmesh

    index = 2  # required index

    bpy.ops.object.mode_set(mode = 'EDIT')
    ob = bpy.context.object
    me  = ob.data
    bm = bmesh.from_edit_mesh(me)

    for face in bm.faces:
        if face.material_index == index:
            face.select = True

    me.update()


I found a workaround:
1) In edit mode, select the vertex group assigned to the bone and hit P to separate the selection from the main object
2) remove the vertices from the main object that belong to the bone (there's actually just one in this case)
3) In object mode select the main object and the separated one and hit ctrl-J in order to join them. Now if I select the vertex at the tip of the part to be moved, there is no influence shown to the main part vertices. Maybe there is a double vertex at that position, but that doesn't create any problem for me for now.


How to get the Controllpoints of the *hull* of a Bezier Curve?

Oh I see the confusion now. The handles of Bezier curve are the "real" control points. These points form the 4 control points for the cubic segment:

And that's also how you convert Bezier to BSplines - per segment. You can make a BSpline segment in Blender with Path curve with 4 points.

You get the described points with text like this:

bpy.data.curves['BezierCurve'].splines[0].bezier_points[1].handle_left
bpy.data.curves['BezierCurve'].splines[0].bezier_points[1].co
bpy.data.curves['BezierCurve'].splines[0].bezier_points[1].handle_right

Like this you get all the blue points.


Is marking and labelling topo points possible?

First, enter edit mode on your surface object, select the point you want to and assign them to a new vertex group via CtrlG.

Create your Circle object. Give him a Child Of constraint, set your topo as the target, and specify the vertex group you just created as well.
You can also add a Track To constraint, with your camera as target, "To" on Z and "Up" as Y, so that your circle always faces your camera.

For the arrow, I think it should do with the Hook Modifier. I never use this one so I'm guessing in the dark here, Bu I guess you need to create a vertex group with the vertices you need to stick on the circle, then add the hook modifier on the arrow object, set the circle as target and specify your point's vertex group.


I can confirm the same behavior. In order to get Blender GUI to run on a remote machine I had to place an openGL file in the blender installation folder. I'm currently looking for a solution to this.


No shadows with Eevee, no render with cycles

I downloaded your file, and there's a shadow in both cycles and eevee. I could comment it but my rep is <50. You could try to copy paste all objects from this .blend file, to a newly created with default settings and check if it's ok

eevee:

cycles:


Can't Find any of the add-ons on "Testing" for 2.8

The Testing Add-ons are only shipped with the experimental buildbot releases, see DevTalk. This is even true if you would compile Blender yourself. Go to the Download section at blender.org and scroll down to the area where the experimental versions can be downloaded:

Those builds should contain the Testing Add-ons you are looking for. If you want to use it in your 2.80 stable release too, you can simply extract it from the zip archive, and put it into the scripts/addons_contrib folder of your 2.80 installation, or your Blender user scripts directory:


This is just because you are viewing it from the front. Move the camera a bit in any direction, and it should look better. You could also give the text a different color in rendering. It isn't transparent, just hard to see


Is there a way to append to an external blend file?

In Blender 2.78, bpy.data.libraries.write() will be an option to use, which will allow any datablock from the blend file to be saved to an external blend file.


How do I access a property in the Preferences in 2.80 with Python?

You can access that Preferences property with the following code:

bpy.context.preferences.edit.keyframe_new_interpolation_type

To use this in a panel:

    row.prop(context.preferences.edit, "keyframe_new_interpolation_type")

The full code (using the UI Panel Simple template found in the Text Editor> Templates menu):

import bpy

class HelloWorldPanel(bpy.types.Panel):
    """Creates a Panel in the Object properties window"""
    bl_label = "Hello World Panel"
    bl_idname = "OBJECT_PT_hello"
    bl_space_type = 'PROPERTIES'
    bl_region_type = 'WINDOW'
    bl_context = "object"

    def draw(self, context):
        layout = self.layout
        row = layout.row()
        row.prop(context.preferences.edit, "keyframe_new_interpolation_type")

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

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

if __name__ == "__main__":
    register()

Which displays like this, in the Object tab of the Properties Editor:

If you need to set this value manually you can see the list of strings this property expects to be set to in the Blender 2.80 Python API.


Unfortunately the playback rate of the VSE is not it's strongest side, however there are a few things you could try to optimize performance:

Select your clip and in the Sidebar make sure that Blend Mode is set to Cross.

Still with the clip selected in the Menus select Strip > Add > Movie > Set Render Resolution

In the View menu, switch Show Cache off.

If none of this improves the rate enough, then add your clips to a folder, and use the Velvet Revolver add-on https://github.com/tin2tin/blender_velvets/blob/master/Blender_2.80/velvet_revolver.py to batch generate proxy files, and then use it for switching between proxy and intermediate files.

Try first to generate proxies which are the same size as your original files, but using the h.264 codec in Velvet Revolver, but if that doesn't deliever a good rate, try lowering the resolution.

On 2. You'll have to change the preview range in Menu > View > Range


Use the HDR as environment texture.
Just line up the camera so that it sees that part of the environment.

Or rotate the environment image until you see the section you are looking for.
How do I rotate an environment texture?
To have shadows of the object create a plane and use it as shadow catcher.


Adding text on a new line in VSE(Python operator)

In Blender2.9 , Wrap-Width slider can be used to  place words on separate lines.


You should use Follow Active Quads.  The problem you're seeing is because the geometry doesn't have a lot of detail so it's not giving you nice curves.  Add a Subdivision Surface modifier and you'll get better results:

You may need to tweak the UVs a bit still in a couple of spots but I think you'll get really close with this.


Where the dimensions of the object have moved in Blender 2.81


I once tried to setup terrain from a heightmap. It would auto-generate terrain tiles using displace, it would create different LOD levels with the decimate modifier and a vertex group (so the edges still lined up).
It worked great in the viewport, but didn't work in the game engine.

Modifiers are a bit strange in the GE. Sometimes they appear correctly, but when adding objects you get CPU spikes (there was one case I worked on where modifiers caused a drop from 60FPS to 20, but that was on lots and lots of objects). Other times they simply don't work. LOD seems to make modifiers in the GE not work.


displaying a powerpoint presentation in the background of a video clip

Blender doesn't have support for reading powerpoint presentations. However you can save the presentation as a sequence of images and display the image sequence within blender.

In powerpoint choose "Save as" and select an image format.
In blender you can easily setup a plane to display the images with the import image as plane addon.
Adjust the texture to display an image sequence.

You can also find the same settings in blender internals image settings.


You can offset the origin of the plane using (for instance) the 3D cursor.  I placed the cursor above the plane and used Alt+Ctrl+shift+C then chose "Origin to 3D Cursor".  That means that the plane's origin is now above it, so the camera is now locked to the new origin through the constraint.


Some walls messed up when I solidified the walls

Looking at the first screenshot, I see that the wall on the left is black, and not grey like the adjacent one. Can you check the normals? If you select the face and use the spacebar and type 'flip normals', it should turn the face in the correct direction.

Barry


Baked smoke shakes during render - Eevee

The "shaking" is due to Adaptive Domain, as the domain adjusts to the size of the simulation it stretches and "moves" the smoke simulation. This is a known old issue as can be seen here as well.


Problem with applying the Subdivision modifier

It's a bad idea to apply subdiv. If you animate a mesh with an armature, try to keep the topology clean and sufficient, but not redundant. Add 3 loops where the limbs are to allow the mesh stretch correctly. When you skin your mesh to the armature (weight paint), it's much easier to handle non subdivided mesh. And keep the armature modifier before the subdivision.
Yes. maybe your model has insufficient geometry, but it doesn't mean you have to subdiv the entire mesh. Just think where and how you want the model to bend, and add geometry (by hand) just there. And master weight paint mode, it will change your model skinning drastically.
As a good start I'd recommend some tutorials to get understand the basics. I like the rigging series by DanPro on youtube. Try this one, to see what matters on rigging. There are tons of nice tutorials, just find that will suit your skills and taste.


How can I make a Driver expression access image RNA data through the image texture node?

Use self in drivers

Can use self in drivers, to see what is going on can make a driver method, register it, and print to system console what the value of self is, and often more importantly what self.id_data is.

Here is a little test driver foo(self) that also returns a random number, so we can see if it is working, and when.

import bpy
from random import random

def foo(self):
    print(self, self.id_data)
    return random()

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

Now add as a driver.

Add the driver directly into the property by typing #foo(self) before its a driver. Once it is a driver simply edit the expression in field.

On first time, Make sure use self is checked, and update deps to fire it up.  If it breaks may have to update deps again.

For the simple driver will see that

<bpy_struct, NodeSocketVector("Vector")> <bpy_struct, ShaderNodeTree("Shader Nodetree")>

is printed to sys console, and the driver is a random value.  Ok then self.id_data is the nodetree to which the texture node belongs.

Extending, will give a value of 4 if no image or no  node named "Image Texture" .. but if there is will return the image width.

import bpy

def foo(self):
    print(self, self.id_data)
    node_tree = self.id_data
    tn = node_tree.nodes.get("Image Texture")
    if tn:
        print(tn)
        if tn.image:
            return tn.image.size[0]
    else:
        print("NO IMAGE")
    return 4.0

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

Could extend further by passing the name of the image texture node and image height or width as an int for instance, and not rely on it being called "Image Texture"

def foo(self, name="Image Texture", index=0, default=0.0):
    ...

        tn = node_tree.nodes.get(name)
        ...
            return tn.image.size[index]

    return default

Now can type #foo(self, "BarTexture", 1, -44) into a prop on nodetree and it will be the height of the image in the node named "BarTexture" or -44 if there is no image or no node.

Notes:

An issue is crossing an ID line in a path for a driver variable.  Starting from material going thru nodetree. If defined as a group then try using the nodetree ID type in a variable  (Haven't had much joy doing this).

Remove print statements if happy with result so you don't spam the console.


Can't access editing tools in layout workspace

You seem to have unvoluntarily disabled Viewport overlays and gizmos (these are all the contour lines, widgets, grids, basically everything that is not renderable geometry). To re-enable them, press these buttons in the top-right corner of your 3D viewport:

The little arrows next to them let you selectively enable/disable elements.

If that's not your issue, maybe it is that you want to enter the Edit Mode?

There are 3 ways to access it:

On the top-left corner of your screenshot, you can see 'Object Mode'. Click on it and select Edit Mode
While your cursor is on the 3D Viewport and your object(s) is/are selected, hit Ctrl + tab. A pie menu appears: select Edit Mode
Still while your cursor is on the 3D Viewport, hit the tab key : it toggles between Edit and Object mode


Transparency turns black after Math:Multiply node. Need help

The problem is that the math node uses a value (=> grey dot) and not a color (=> yellow dot). You'd rather use a RGB Curves node (ShiftA => Color => RGB Curves) and change it's C value. This will give you what you want.

Look at how the backdrop changes. The first time it's the normal render without any compositing. It still has an alpha channel. The second time it's with the math note. The alpha channel disappears. The third time it's with the RGB Curves node. The colors get strengthen but the alpha channel stays.


Objects appear deformed in Object mode but normal in Edit mode

Check that you don't have any "shape key" active or configured.
check screenshot:


QUICK TIP: The proper edge flow of your mesh is the key to a good looking model. Your topology is bad- it doesn't define the head's shape well.
Start from extruding the eyelid circular shape, then do the same with lips. Keep going further and then connect eyelid and lips meshes together. And remember to avoid ngons (you've got some there).

I hope you get the idea. Of course it's one of the topology variant. Type 'manga head topology' in google graphics to see some different topology edge flows examples.


What should I track for accurate rotation stabilization? Or, how can I stabilize motion timelapse?

Rotational stabilisation requires 2 points/trackers that remain stationary relative to each other not the edge of frame or camera.

If that isn't available then your other solution will require a good 3d solve, from lots of trackers. But it sounds like you may not have much to track there either.

Perhaps you could use 2 planar tracks they tend to track features that cover an area instead of a point.


how do I make to recognize the body of the robot, as blender recognize just the body?

Hint: You can enable Main Menu/Game/Show Physics Visualization. It allows you to see the physics mesh while running the game.

When you use the mesh object as presentation object and as physics object - ensure to select the right Physics/Collision Bounds/Bounds.

When you use one of the primitive collision shapes (box, cylinder ...) the mesh should be symmetrical around the origin. This means the origin should be in the middle of the object. According to your description, this is not your current situation.

Example:

The origin of this mesh is not in the vertical middle. With the primitive shapes the mesh will be out of the bounding box and out of shape:

When you use detailed shapes the origin does not need to be at the middle. But they need much more processing power:

In all cases the origin should be inside the bounding box of the mesh. Otherwise the physics might calculate results you do not expect.


Using difference modifier on two objects doesn't always work

For the boolean operation to work properly you need to fix the mesh first.

Select the text object
Go into edit mode, Tab
Select all, A
Remove the doubles, W -> Remove Doubles
Fix the normals, Ctrl N

Once you do this the boolean operation will work properly


Is there a formula for processing a rendered area in compositor without affecting other areas?

Sorry long day ... I'm not sure if I catch the point ... if your issue is lost alpha after Colorramp add Set Aplha node behind. Colorramp is black&white node only.


Running this script will remove doubles on the currently selected mesh and export the file with a filename appended with -unity

You can then set unity to read the -unity blend and run the script instead of save.

import bpy
newfilename = bpy.context.blend_data.filepath.replace(".blend","-unity.blend")
bpy.ops.object.mode_set(mode='EDIT')
bpy.ops.mesh.select_all(action='TOGGLE')
bpy.ops.mesh.remove_doubles()
bpy.ops.wm.save_as_mainfile(copy=True, filepath=newfilename)


Dnytopo constant at 6 looks really bad, not like video I am following (blender 2.8)

I found this same issue coming into the tutorial, and one of the things I did was check the comments and a user with the name Daium said to try setting the resolution to 60. I think it is because this person in the tutorial had a different scale with numbers. anyway I tried it and it worked.


In order to flatten faces the surface, select all the faces that you want to flatten and scale 0 to the axis you want it to be flat to. I'm assuming you want to flatten it to the Z axis. In order to do this, press SZ 0 enter.


Yes This is possible.

For a cylinder:

Press ShiftA> Add mesh > Cylinder
Press F6 and set the Cap Fill Type to Ngon.

If you are looking to do this from python:

bpy.ops.mesh.primitive_cylinder_add(radius=1, depth=2, end_fill_type='NGON', view_align=False, enter_editmode=False, location=(-2.06615, -0.413393, 3.45981), layers=(True, False, False, False, False, False, False, False, False, False, False, False, False, False, False, False, False, False, False, False))

Or have a look at the bmesh api.

For doing this in the interface, usually one uses Edit mode (perhaps you could elaborate on why this doesn't work for you?). To create an ngon in edit mode, select the faces you wish to convert to a single face and press F.


How to make "Idle" animation like in "Overcooked"?

If you want to make it bounces a bit like in your animated gif, you can select your top bone and altP > Disconnect Bone. The bone remains the child of the bottom bone but it can move independently. Now you can move it up and down. About the rest of your question, in my opinion it's much too broad for a forum.


How to paint a gradient with TexDraw brush?

Strokes set to Line do not give you the ability to see a gradient travel along it, or curve for that matter. TexBrush with gradient and pressure in the Strength ticked on (be sure to adjust the strength to allow for some fluctuation) can be useful for changing the color along the gradient ramp, but then it is really about using your manual stroke here to control the pressure - wit hthat, I sometimes play with the Shift-S Smooth Stroke or Lazy Stroke to control my line/curve while painting.


How to set a specific distance between two vertices?

In this particular case, you can slide (G G)the vertex down to the bottom corner, and then G Z and '0.77' to move it back again.

In general, when things aren't nicely lined up,

With snap set to 'Vertex' and 'Active',
First create a Custom Orientation (Ctrl AltSpace) from the edge you want to measure down (or parallel to).
ShiftD duplicate any vertex to make one you can use as a snapping source/target.
Snap your new loose vertex to a starting point
GYY+(numerical entry) your vertex parallel to your Custom orientation.

you now have a measured point to snap other things to.

I use a lot of Custom Orientations, so I check 'Use after Creation' and 'Overwrite Previous' in the Tool Shelf.

Using Custom Orientations and a loose vertex, with the pivot set to 'Active Element', you can extend this method to measure angles around an axis in the custom edge's direction, through the active element (RYY+(numerical entry))


2 Particles systems (1 curve guide) Affecting both.

You can turn down the curve guide effect under "Field Weights" on individual particle systems:


Most of the retargeting tools copy the bone rotations from the .bvh motion capture into FK bones of the rig. After that the animation can be copied to IK bones through FK/IK snapping scripts. When doing this manually from .bvh to a simple IK rig, you will encounter 2 difficulties:

Problem 1: The IK rig has extra control bones that the .bvh does not have. The rig structures differ. You need to add these bones to the .bvh rig and drive them with constrains from the motion captured bones. You have to usually add IK Pole bones, Hip location,.. (depends on the complexity of IK rig what you need to add) so you have all the bone locations and rotations to drive all the control bones of the IK rig:

Here the yellow bone tracks head of a bone up the chain and tail of a bone down the chain with 50% influence to stay right in between them. The green bones are just parented to yellow ones.

Problem 2: Usually the source .bvh armature has different proportions than the rig we need to transfer the capture to. When copying from FK to FK, there are not so many issues with proportions, because only the rotations get copied. IK rig on the other hand also relies on position of its controls. So before copying those, the .bvh source rig's bones have to be edited to proportion.


Have you tried using an angle-limited bevel modifier after the solidify?  You can tweak the angle as appropriate, but that ought to dynamically add more geometry exactly where you need it to convince the subsurface that you want more defined corners and edges.

It has the advantage that it's dynamic and doesn't care about the shape of your objects - but the disadvantage that it DOES care about the angles involved, and it will most certainly add more geometry to the mesh - but then, the manual method of adding loopcuts also does that.  You get to pick how and where though, which can help.

I had a play around and using the other limit modes on the bevel doesn't seem to help much, but if angle limited isn't working they are potential options also.


Sine Wave
Producing a sine wave is easy as Sine is one of the math functions in the Blender Internal Converter --> Math node.
However, a normal sine is no good as a direct factor for a mix node, since a sine wave produces values between -1 and 1, and the node expects a value between 0-1. To produce sine-like oscillating values between 0 and 1 I used the equation ( sin(x) + 1 ) / 2.
The node tree looks like this:

The factor values produced by this node setup look like this (green line):

Square Wave
A square wave is also pretty easy, since we only need to discern between positive and negative values, which we can do using the "Greater Than" or "Less Than" nodes:

And the factor values:

Triangle Wave
Based on this algorithm as implemented in wolfram, I used the following equation to generate a triangle wave:
pi/2 * asin( sin(pi * x) )
Since there is no inverse sine (asin) in the math node, I used the identity function (that employs the inverse cosine which can be found in the math node's repertoire):
asin(x) = pi/2 - acos(x)
Also, the original triangle wave creates values between pi/2 and -pi/2 more or less, so I adapted it thus to produce values between 0-1 (more or less):
( asin( sin(pi * x) ) + pi/2 ) / pi
The node setup looks like this:

This is by far the ugliest and biggest node setup, but that's the best I could manage. Here's how the factor values look:

Sawthooth Wave
Based on this answer, again adjusted to fit values between 0 and 1, I used this equation as basis:
( ( x + 1 ) % 2 ) / 2
Node setup:

Factor values:


Is there a way to mass-rename an object's suffix?

Not natively, no, but you can try one of these addons:

Name Panel Addon http://blenderartists.org/forum/showthread.php?272086-Addon-Item-Panel-amp-Batch-Naming-1-4 or
Batch Rename Datablocks http://wiki.blender.org/index.php/Extensions:2.6/Py/Scripts/Object/Batch_Rename_Datablocks


How to make objects in foreground appear darker than the background?

There are two fast ways this could be accomplished.

The first way is through lighting. Make the background brighter, and don't cast nearly as much light on the foreground. The light would still bounce around, lighting up the foreground a tad bit, but that's natural and would still look good.
To emphasize this effect even more, turn up the brightness of the background lights, and turn down the exposure.

The second way would be to use render layers, and composite the foreground over the background using an alpha over node. This way, you could finely tweak the colors, saturation, and value of both the foreground and background individually, making awesome results. So, basically, you'd darken the foreground to almost nothing, but keep the value of the background and maybe even boost saturation.

Hope this gets you going in the right direction!


If you make File > External Data > Find Missing Files you'll find your files but I don't know how to easily show their location. You could pack them all with File > External Data > Pack All Into Blend then unpack to another folder if necessary: File > External Data > Unpack All Into Files.


Connect Mix Shader to Surface socket in Material Output node not to Displacement.


Reorder vertices of a mesh in Animation Nodes

Yes we can, matter of fact, we have a node called Sort List just for that. For instance, If I were to sort the vertices based on their x locations, I would do:

e.x means we want to sort based on the x location of the element. Now, if I wanted to sort it based on the distance between it and some other vector, the distance can be used as a Key List:

For more info on how to use the Sort List Node, see the documentation.

But wait! It is not that simple. After reordering the vertices, the edge and polygon indices will now be pointing to wrong vertices. So we have to correct them such that they point to the new indices of vertices. To do that, we have to know at which index did each of the vertices landed in the new list, in other words, we want a list that tells us the new indices of the vertices. The sort list only returns the the sorted list, so we will have to use some other method. The best method I know would be to use numpy.argsort which returns the new indices of the list elements instead of the list elements themselves. So, in an expression node, I will write:

numpy.argsort(list.asMemoryView())

Where list is the required list to be sorted and it should be numeric type, not an object. Make sure to import numpy in the advanced node settings by replacing math with numpy. Now that we have the indices list, we can get the sorted list by getting the elements at those indices:

Now that we have computed the the sorted vertices list. We can go ahead and compute the new edge and polygon indices lists. We are going to compute them by looking at their indices and seeing what is the indices of those indices in the computed indices list, in other words, we are going to search for each of the indices and use their index to create new edge and polygon indices. However, instead of using the search node which is expensive, we are going to create an inverse look up table which is easily done as follows:

Where the iterator is the indices list and the parameter is an integer list of the same length, possibly the indices list itself. Next, we are going to loop over edges and polygon, get the indices from the new indices list at their indices and create edge and polygon indices from those new indices:

And then we compute the new edges and polygon and output them:

And you can see that they became sorted from left to right, that is, from the lowest x value to the highest:

Similarly, I can sort based on the distance from the origin as follows:

Which produces:


Can you use use Loop-Cut tool with ngons?

Loop cut intentionally only cuts quads.

To cut across ngons you can:

Use the knife tool to cut up the face how you like.
Select 2 vertices and run join (Jkey).

Note, we have support for ths in the code, but after discussion with users, disabled it - see BMW_EDGERING_NGON
See:
http://lists.blender.org/pipermail/bf-blender-cvs/2012-March/043815.html


Hair goes out of place when moving the armature!

You should enter in weight paint mode and see if that arm is affecting other parts in the mesh


How to create a semi transparent plastic shader?

There are elements of Refraction, Glossy, and Subsurface scattering in there so how about something like this :

This produces the following :

Vary the Mix factors, roughness and Subsurface scale to get the desired effect. Don't forget to have something in the scene to reflect/refract - eg, world environment texture and/or patterned surface, and suitable lighting, etc. Also, bevel any edges and ensure to add thickness.


How to create splash of a ball falling on water?

To have the rigid body affect the fluid, simply go to the fluid obstacle settings and check Export animated mesh. However, while the rigid body will affect the fluid, the converse is not true, so the fluid will not slow down the rigid body in any way.

Keyframed animation is the way to go in this case.


Help unbind all materials from selected object

Try this, it affects all selected objects.
import bpy
for ob in bpy.context.selected_objects:
    for ms in ob.material_slots:
        if ms.material and ms.material.users > 1:
            ms.material = ms.material.copy()

Note that it may not do what you expect if an object has two slots with the same material.


How can I make honey drip down a surface endlessly?

Animated UV map:

One way of going about this is to set up an animated UV map. You will have to have a good material for your honey, and then you animate your UV texture mapping so that the texture appears to be dripping down the sphere.

Here I have started with a UV sphere and kept the default unwrap:

I've set up a simple material using only a texture for the base color. The effect will look much better if you also have normal and roughness textures. If you have the node-wrangler addon enabled (included in Blender, just turn it on in prefs), select your image texture and press CTRL + T to add the Texture Coordinate and Mapping nodes. Plug these into every image texture you end up using.

In terms of the actual animation, you're going to be animating the Y-coordinate of the Mapping node. I inserted a single keyframe at frame 0 with Y=0.0, and a single keyframe at frame 60 (or whatever the last frame of your animation is) with Y=1.0.

The reason you set the first keyframe at frame 0 even though your animation starts playing at frame 1 is so that you don't have two frames with the same position.

Make sure you set the interpolation mode for these keyframes to linear.

Here is a basic demo of the set up:


Move object continuously after being triggered by near sensor

Although you could have the reset distance at 10,000 blender units before it stops moving, and this may work for what you want, that is not at all the correct way to do this.

From what I can tell from your question, you want to have the cube detect being near the cylinder, and then after that, you want the cube to continuously move. The Near sensor detects the distance from the cylinder, and that sets the Boolean property to true. When the Boolean property is true, it will continuously make the cube move.

If you wanted to make the cube stop moving, you could simply have another property actuator assign the value of the property "PropName" to false. then the property "PropName" will obviously no longer be true, and thus "Property" (sensor) will no longer be true and will not send the positive pulses to "Motion" (actuator) and as a result, the motion will stop.


Non blender internal textures

There may be some textures in blend that don't have the use_interpolation property.  For example switch to cycles and add a new brush texture.  bpy.data.textures["Texture"] the newly added one, doesn't.

Check whether the texture has the attribute with hasattr

>>> for t in bpy.data.textures:
...     t.name, hasattr(t, "use_interpolation")
...
('dice', True)
('Tex', True)
('Texture', False)

Find all with that property, then set.

bi_textures = [t for t in bpy.data.textures if hasattr(t, "use_interpolation")]
for t in bi_textures:
    t.use_interpolation = False

or get the textures from the materials on the planes. Test code to get all textures on selected nesh objects

import bpy

context = bpy.context

textures = [ts.texture
        for o in context.selected_objects if o.type == 'MESH'
        for m in o.data.materials
        for ts in m.texture_slots if ts and ts.texture]


How can I model something that behaves like molasses?

For a still image, many tools can be used: an experienced 3D artist will probably use just mesh editing or sculpting. Someone would use particles and meta objects. I would personally go with a two step approach: fluid simulation first to get an overall realistic shape, then sculpting, mostly to smooth it well and make it look nice.
TL;DR
The very short answer if you're going down the "Fluid simulation" route is: a low "Exponent" (1 - 2) in the Fluid > Domain > Viscosity settings makes a thick fluid.

Step by step example

Scale. Make sure your existing objects (empty candy and plane) have the dimensions of a few decimeters = ~0.1 to 0.5 Blender units in v2.79b (it's not important that they are exactly real-size, EDIT: and actually if they are too small the fluid simulation could not work at all, but they shouldn't be 1 unit long either, i.e. 1 meter). Resize them, then apply their scale (CtrlA).

Set up a Fluid simulation. Like this:

a Fluid-type ball inside the cavity
your existing candy as Obstacle
a non-slip Domain cube with its bottom face corresponding to your standing surface. Reduce Exponent in viscosity to 1 or 2
set the Final resolution to a medium value (e.g. 120) and the Viewport Display to Final, and reduce the Scene's End time to something like 80. You don't need 250 frames for this!

Bake the fluid cache. Then choose a frame that you like, go to the Modifier tab and Apply the Fluidism modifier

Sculpt. I would mostly use the Smooth brush, and a bit of Inflate and Grab to add variation

Shading. Give it a specular, smooth, transparent, translucent material.

(I've also added some volume-emitted particles as bubbles, with a transparent, IOR<1 material)


How To Make A Board Game Piece With Vector Displacement

Looking at the second screenshot it seems like the RGB curves only contribute to the Viewer Node, they are not in any way connected to the Displacement Output Socket.


blender animation not updating in render mode but working in texture mode

If you open the video sequence editor  you will find an image sequence strip. Blender will render the sequencer with higher priority than the 3d view. The images can't be found, therefore a blank frame is rendered. Disable the Sequencer to ignore the image sequence in the sequencer and to render the 3D View and the Compositing setup.

Uncheck Sequencer in the Render Settings.


How to make wheat stalk stiffer in Cloth Physics?

I recently found out about the Surface Deform Modifier, so I decided to try that on the wheat. I surrounded the wheat with a low-poly mesh, and gave the low-poly mesh the cloth modifier instead. To keep this mesh from falling over, I added pinning to a few vertices I extruded above the mesh. It works great now, not only because there is far less bending, but also because now I don't have to worry about the little hairs swinging all over the place.
Below is a screenshot of the wheat.


The only way I can get anything like what you're seeing is to reduce the viewport's "clipping" END setting (press N and open the VIEW tab) to something below the START setting then approach the cube until this happens...

Another point might be to ask where you downloaded Blender from?  I make a point of using the original/authoring site, never a third party site for any s/ware.

This is obvious I know but failing all else, you might also want to explore the possibility of it being a problem between Blender, the graphics card or it's drivers, or perhaps your operating system and/or it's version.

I see your latest comment and note that you're using Win XP?  That's pretty old isn't it?  Blender has come a long way since the older versions of Windows.  Perhaps XP can't handle what Blender is doing re - shading etc.

When all else fails, look for the things it cannot possibly be!

EDIT:  I've since found out that XP is not supported by Blender versions beyond 2.76B


Issue un-extruding flat bottom of an object


It looks like you have enabled ambient occlusion in your viewport. You can control it in the Properties region ‣ Shading.

For more info, see the Shading Panel manual chapter.


Unfortunately the system was removed... for now. https://developer.blender.org/rBM7254


Seperate a border/frame from an object using offset i Blender?

select the outer face ring

select more and repeat as long as you need it

seperate -> Selection

delete unwanted part

tutorial:
https://youtu.be/PuGHyzvwhWk


How to change Transform Orientation with keyboard in Ubuntu

Personally I'd change the desktop manager binding from alt to super, but in Blender you can change it by going into User Preferences > Input. Then type in the search box "Orientation". You can click on the "Alt Spacebar" field, after which you can give the wanted key combination for Orientation Selection.


Rendered image files are unreadable files without specification

How about checking the "File Extension" option?


Only game engine purposed materials work in their specific game engines, just like only specific render engine materials work in their specific Render Engine of origin. (Blender Internal Materials only work in Blender Internal Render, not Cycles, and vice versa).

Every rendering environment (realtime, game engine or otherwise) uses it's own specific material definitions specially designed for their particular task and non other.

A few exceptions are probably generic material definition standards like OSL (Open Shading Language) or GLSL (OpenGL Shading Language) or RenderMan Shading Language among others.

As far as I know there is nothing stopping a render engine from using Cycles materials, I am sure they could hypothetically be be easily ported, actually more the other way around, a game engine could perfectly be designed around rendering Cycles shaders.

In fact one already exists, in the upcomming Blender 2.8 the new viewport realtime OpenGL render engine EEVEE can and uses mostly cycles material definitions and display them in real time. Cycles object viewport previews will also be generated by EEVEE.

Bottom line is, to the best of my knowledge the problem doesn't lie in the materials themsleves, the shaders, the languages or anything else, the problem lies in optimization and purose.

Game engines need speed and responsiveness above all, they can't spend the endless time needed to render a Cycles scene, as such corners are cut. You can't have all the nice things an offline render provides like raytraced reflections, indirect lighting, mesh lights, refractions etc, as such that eye candy has to be faked with various complex and intricate techniques.

Real time materials are therefore optimized for these tasks, make abundant use of pre-calculated effects, baked maps, lots of textures, screen space ambient occlusions, deferred rendering, etc., whereas a Cycles material aims for realism and flexibility of use at the expense of render time.

Making render engines compatible with third party material definitions is also a huge complex task, error and bug prone, can cause artifacts and unexpected results, may introduce negative implications like worse performance and feature limitations.

See for example Cycles support for OSL shaders, you can have them but while using them you can't get GPU acceleration for example.

It is also often pointless to do so, there are no real gains in say Unreal or Unity supporting something as niche as Cycles shaders in their pipeline. Business strategies and market competition also probably restrict sharing proprietary shaders between rival companies.


Rigging a Wheel to Turn Corners: Drivers vs. Bones

Both approaches will not work when dealing with corners, they will only work in straight line. There is more about why that is here:

Making wheels spin as car moves

You need to either:

construct a path for the car (or for each wheel if you want to be precise) and drive the wheels with that
Use Animation Nodes addon, this lets you access animation F-curve data and compute the wheel rotations
Use rigid body physics to simulate the wheels and collision with ground, bake the simulation into keyframes
Create a PyDriver (a driver with added function through script that can access blender f-curve data) or a frame change handler. With both you can access animation to compute the path and drive the wheels correctly
Write a script for your rig that will add/update animation of the wheels to the f-curves, similar to a script that would snap FK and IK bones in a rig, but with different function
Write an own engine that will simulate the wheels collisions and add it through app-handler to execute on each update of the car rig


This may possibly be that you actually have local transform enabled for the object you are trying to move. If you have rotated the object around 90 degrees, it would appear that pressing the Y key would be moving the object in the Z axis because of moving the object locally. If you don't want this, then simply disable local transform in the viewport.


Project into 2D
The verts and edges are wound in order. Knowing the face normal can walk around the edges in a face, using the vector of the "incoming" edge, and vector of "outgoing" edge can calculate the internal angle as as outlined in Finding Internal Angles of a Polygon  Blender winds its faces in a counter-clockwise direction.
IMO other answers  fail to take this into account, see below
Blender has an angle_signed method for 2d vectors.  To use here may require having an arbitrary "Greenwich" point as a reference.

If not colinear, The three verts of the 2 edges form a plane

The corner of 2 edges is the middle vert (b) Subtract
this from other vert of each edge (new origin)

The cross product of the two edges is the axis of rotation (normal to
plane)

Change the space to project (rotate) corner plane into XY plane to represent the corner edges as 2D xy vectors.

Test script. By way of point of difference have used an edit mode bmesh. In edit mode, select the faces you wish to see the internal angles of, then run script.
import bpy
from mathutils import Matrix, Vector
from bpy import context
from math import degrees, atan2, pi
import bmesh
# project into XY plane,
up = Vector((0, 0, 1))

ob = context.object
me = ob.data
bm = bmesh.from_edit_mesh(me)
def edge_angle(e1, e2, face_normal):
    b = set(e1.verts).intersection(e2.verts).pop()
    a = e1.other_vert(b).co - b.co
    c = e2.other_vert(b).co - b.co
    a.negate()
    axis = a.cross(c).normalized()
    if axis.length < 1e-5:
        return pi # inline vert

    if axis.dot(face_normal) < 0:
        axis.negate()
    M = axis.rotation_difference(up).to_matrix().to_4x4()

    a = (M @ a).xy.normalized()
    c = (M @ c).xy.normalized()

    return pi - atan2(a.cross(c), a.dot(c))

selected_faces = [f for f in bm.faces if f.select]
for f in selected_faces:
    edges = f.edges[:]
    print("Face", f.index, "Edges:", [e.index for e in edges])
    edges.append(f.edges[0])

    for e1, e2 in zip(edges, edges[1:]):

        angle = edge_angle(e1, e2, f.normal)
        print("Edge Corner", e1.index, e2.index, "Angle:", degrees(angle))

Test run on concave ngon

2x2 grid center vert dissolved. Bottom vert moved to origin making a 270 degree internal angle between edges 5 and 1
Face 0 Edges: [1, 6, 2, 7, 3, 4, 0, 5]
Edge Corner 1 6 Angle: 45.0
Edge Corner 6 2 Angle: 180.0
Edge Corner 2 7 Angle: 90.0
Edge Corner 7 3 Angle: 180.0
Edge Corner 3 4 Angle: 90.0
Edge Corner 4 0 Angle: 180.0
Edge Corner 0 5 Angle: 45.0
Edge Corner 5 1 Angle: 270.0

For file IO consult the python docs. (Or see other answers).
Re other answers, angles when run on ngon above
@lemon
[135.00000034162267, 0.0, 90.00000250447816, 0.0, 90.00000250447816, 0.0, 135.00000034162267, 90.00000250447816]

@MohammadHosseinJamshidi
[45.00000125223908, 90.00000250447816, 180.00000500895632, 90.00000250447816, 180.00000500895632, 90.00000250447816, 180.00000500895632, 45.00000125223908]


Does Blender continue to work in the background despite "No responding", the blue loading circle and the "milky" picture, and is it worth waiting?

Yes indeed it does. No progress bar is because of threading: Blender was expecting the script or whatever to run quickly, or simply can't run multiple threads with the process for whatever reason (EEVEE is an example as Blender cannot multithread OpenGL to EEVEE render and GUI render at the same time), and the GUI updater is waiting for the process to finish.*
*In some rare cases, something could have gone wrong that was also causing the hold-up.


How to find pixels which are getting occluded in the next frame?

Please see the panel ... object relations pass index. This information can be examined in the compositor.  This is generated in the object index render pass for Cycles. You must enable that pass.

There is also Cryptomatte.


issue with grease pencil and tablet pressure

For those Who are interested i submitted a bug report and got a solution:
It is a stencil setting in the stroke panel, to disable this the feature Is "self overlap".
Blender stencil setting

Credits antoniov developer for clarification.


Turn weight paint(vertex groups) into vertex paint?

I think you will still have to do a bit of scripting to get the following to work but it does most of what you want.  A while back, someone posted a question about how to convert an existing script that turns Weight Paint to Vertex Color Paint, he posted the script link and there are a couple reasons why I decided to post this as an answer instead of only directing you to the link.
First, there is an important step necessary to get this to work properly.
Second, I'd like to also post the script here directly in case the link to the external site goes down, this way it will still be available here.

To start with, Vertex Color Paint starts off as all white and if you try to use the Addon with the Vertex Colors as all White then it fails weirdly.  The first results I got looked like the following.  It transitions from white to grey then back to white.  It's not black where the blue is in Weight Paint mode.

However, if you first add a Color vertex group and then make that group black, the Addon works fine.  Just set the brush color to black and use the Set Vertex Color shift +k

Now you will have all black vertex colors.

So now you can enter weight paint mode and use the Addon which can be found in the spacebar search menu under Weight2VertexCol

You should get results something like the following.

Now the fun part, you have to modify the Addon to invert black and white.  Fortunately, the math for this is easy, unfortunately I don't know Python scripting very well and I'm mediocre with math.  Now if I think correctly(which I don't always do) you can use (x*-1.0)+1.0 to invert black and white.  So I assume if we find the place in the script that writes the Vertex Colors and we place that variable where the x is in the above formula then the script should do what you want.

I'll just post the script for now and then maybe someone can figure this last part out. I'll be really surprised if that code works without some indentation reformatting using a program like PyCharm CE since the code window here botched the copy and paste and I had to do a bunch of manual indentation.  Anyways, here is the link to the script on the external site so people can just use this copy as a last resort.

https://bitbucket.org/kursad/blender_addons_weight2vertcolortransfer/src/42070d95e0063df441b4f2d617492669b690592c/src/vertex_color_weight_transfer.py?at=master

The script has the filename -> vertex_color_weight_transfer.py in case anyone from the future wants to Google it.  His name is listed in the script below.

I put some notes after the script about how I think you can modify it to make Red = 0.0 and Blue = 1.0 instead of what it does now(Unless I'm confused and it already does.)

import bpy
from mathutils import Color
import random
from bpy.props import *

import bmesh

bl_info = {
    "name": "Weight2VertexCol",
    "author": "Kursad Karatas",
    "version": (0, 1, 0),
    "blender": (2, 6 ,6),
    "location": "View3D > UI panel >CopyWeightColors",
    "description": "Transfers Weights as Vertex Colors",
    "warning": "",
    "wiki_url": "",
    "tracker_url": "",
    "category": "3D View"}

class Weight2VertexCol(bpy.types.Operator):
    """Tooltip"""
    bl_idname = "object.weight2vertexcol"
    bl_label = "Weight2VertexCol"
    bl_space_type = "VIEW_3D"
    bl_options = {'REGISTER', 'UNDO'}

    method=bpy.props.BoolProperty(name="Color", description="Choose the coloring method", default=False)

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

def execute(self, context):
    transferWeight2VertexCol(context, self.method)
    context.active_object.data.update()
    return {'FINISHED'}

def transferWeight2VertexCol(context, method):
    me=context.active_object
    verts=me.data.vertices

    col=Color()
   col.h=0
    col.s=1
col.v=1

#vcolgrp=bpy.context.active_object.data.vertex_colors.keys()

try:
    assert bpy.context.active_object.vertex_groups
    assert bpy.context.active_object.data.vertex_colors

except AssertionError:
    bpy.ops.error.message('INVOKE_DEFAULT',
            type = "Error",
            message = 'you need at least one vertex group and one color group')
    return

vgrp=bpy.context.active_object.vertex_groups.keys()

vcolgrp=bpy.context.active_object.data.vertex_colors

#Check to see if we have at least one vertex group and one vertex color group
if len(vgrp) > 0 and len(vcolgrp) > 0:
    print ("enough parameters")

    #Colored
    if method:
        for poly in me.data.polygons:
            for loop in poly.loop_indices:
                vertindex=me.data.loops[loop].vertex_index

                #Check to see if the vertex has any geoup association
                try:
                    weight=me.vertex_groups.active.weight(vertindex)
                except:
                   continue

                #col=Color ((r, g, b ))
                col.h=0.66*weight
                col.s=1
                col.v=1
                me.data.vertex_colors.active.data[loop].color = (col.b, col.g, col.r)

    if not method:
        for poly in me.data.polygons:
            for loop in poly.loop_indices:
                vertindex=me.data.loops[loop].vertex_index
                #weight=me.vertex_groups['Group'].weight(vertindex)

                #Check to see if the vertex has any geoup association
                try:
                    weight=me.vertex_groups.active.weight(vertindex)
                except:
                    continue

                col.r=weight
                col.g=col.r
                col.b=col.r
                me.data.vertex_colors.active.data[loop].color = (col.b, col.g, col.r)

class MessageOperator(bpy.types.Operator):
    bl_idname = "error.message"
    bl_label = "Message"
    type = StringProperty()
    message = StringProperty()

    def execute(self, context):
        self.report({'INFO'}, self.message)
        print(self.message)
        return {'FINISHED'}

    def invoke(self, context, event):
        wm = context.window_manager
        return wm.invoke_popup(self, width=800, height=200)

    def draw(self, context):
        self.layout.label("A message has arrived")
        row = self.layout.split(0.25)
        row.prop(self, "type")
        row.prop(self, "message")
        row = self.layout.split(0.80)
        row.label("")
        row.operator("error.ok")

#
#   The OK button in the error dialog
#
class OkOperator(bpy.types.Operator):
    bl_idname = "error.ok"
    bl_label = "OK"
    def execute(self, context):
        return {'FINISHED'}

def menu_draw(self, context):
    self.layout.operator_context = 'INVOKE_REGION_WIN'
    self.layout.operator(Bevel.bl_idname, "Weight2VertexCol")

def register():
    bpy.utils.register_class(Weight2VertexCol)
    bpy.types.VIEW3D_MT_edit_mesh_specials.prepend(menu_draw)

    #error window
    bpy.utils.register_class(OkOperator)
    bpy.utils.register_class(MessageOperator)

def unregister():
    bpy.types.VIEW3D_MT_edit_mesh_specials.remove(menu_draw)
    bpy.utils.unregister_class(Weight2VertexCol)

if __name__ == "Weight2VertexCol":
    register()

The following lines look like where the Red and Blue are being transferred to Black and White.
The col.r = weight is a pretty good indication.  So is the fact that all three color channels are being assigned the same information. That is how you make a grey scale color which is what we are looking for here.

col.r=weight

col.g=col.r

col.b=col.r

So, as a starting point, I would modify the first line of that snippet to be

col.r= (weight*-1.0)+1.0

and then I would test it.  It should do what you want I think.

What would be even better is if you were to find a way to modify the code so that it automatically makes the Vertex Colors all black for you as part of the script which will save you a few steps.

UPDATE:  I tested the invert formula and now the script seems to do what you want, here is the result.  Also, with the greyscale inversion added, the initial Vertex Colors should start off white instead of black so this saves a bit of setup for you.


In the picture, the two parts are both selected.  If you came straight out of Edit Mode to Object Mode and then tried to move one, you will of course move both while they're both selected.
Press A to toggle selection until nothing is selected, then right click on the one you want to move.


I cannot get this cylinder to follow the bezier curve

see what I suggested above it could help, perhaps

set a bezier curve, and a little curve circle

then set the curve circle as bevel object of the bezier:

when finished (perhaps better keep a copy) you can convert to mesh with ALTC

edit: adding a less linear bezier

or a real spiral (see How to make flat spirals)


Popping medal:

activate an edit actuator in Add Object mode


How to correctly enable Cycles from add-on?

I found a solution looking at how bpy.ops.preferences.addon_enable(module="cycles") was using addon_utils.enable, it needed default_set=True as an argument, which forced the add-on to be checked in the preferences and fixed the errors.
def cycles_check():
    import addon_utils
    is_enabled,is_loaded = addon_utils.check('cycles')
    if not is_loaded:
        print ('Cycles is required to use Photographer, enabling the add-on automatically.')
        success = addon_utils.enable('cycles', default_set=True)
        if success:
            print ('Cycles is now enabled.')
            return True
    else:
        return True


Exporting a blender model to .x3d for 3D printing it became too big to print. The scale was completely messed up.
Collada, .obj and .ply all export in the right scale, x3d does not.
All printing-tutorials say you have to set the 'unit scale' in the scene tab to 0.001 and the 'length' to millimeters. However, .x3d doesn't understand this 0.001 value.
MY WORKAROUND:
Set the 'unit scale' to 1 and your .x3d export will be in correct scale. A 10mm cube will print as a 10mm cube, the way it should be.
I wonder why the other file type exporters have no problem with this. Should the .x3d exporter be fixed or is it... uhm... just me?


Try the Bisect Function

3D View > Mesh > Bisect, requires a Face Selection

This allows you to split the mesh along a plane you can define by dragging, or numerically. If your Operator Panel is not open, hit F6 to show it.
It come with a bunch of useful options, like

Fill, which fills the cut edges with faces
Clear Inner/Outer which remove one or both sides of the cut
Axis Threshold that gives the cut adge some fuzzines in where the cut-off happens.


How to link/append with a Python script?

After trying out the interface for a while, i finally found the values that seem to satisfy the API. Here is a code snippet:

blendfile = "D:/path/to/the/repository.blend"
section   = "\\Action\\"
object    = "myaction"

filepath  = blendfile + section + object
directory = blendfile + section
filename  = object

bpy.ops.wm.append(
    filepath=filepath,
    filename=filename,
    directory=directory)

Hint: The directroy string must be terminated with a trailing "\\". If you do not do that, then you always get an error "not a library". I also found that you only need to supply filename and directory, which makes some sense:

bpy.ops.wm.append(filename=filename, directory=directory) # works

However this does not work, no idea why:

bpy.ops.wm.append(filepath=filepath) # does not work (why that?)


How can I make a long strand of bones without having to extrude each one?

Subdivide One Large Bone

Thankfully there is a very easy way to do this: simply create one large bone the length you want your final strand of bones to be, then Subdivide that bone repeatedly:

Select bone -> TAB -> W -> Subdivide


Somewhere along the way, you probably duplicated all faces by accident.  If that were the case, you should be able to delete them all at one time, because they're connected.  Select one of the extra faces and hit ctrl-L.  This selects all geometry that is connected to this face.  Now you can delete it all.


If this is the look you are aiming for, unless you need to export this somewhere else, you could achieve it just by using generated coordinates.

Simply use world coordinates for your texture. Start with Object coordinates, then run them through a Vector Transform node from Object to World.

Alternatively, I imagine your bat emitting sound waves will be moving, so instead use an external object as source for texture coordinates, like an empty, then animate its position or parent it to the bat.

In both cases just animate the Color Ramp's position parameter for the stops to achieve the "moving rings" effect.


One possibly solution to to render the image twice - once with the Envionment and the other without the environment - and then use the compositor to combine the images, using the render without the environment for the chosen object.

To demonstrate, consider the following scene :

The cube is set to emissive (to reflect in the surfaces of the other objects), Suzanne is reflective, as are the two spheres. The left-hand sphere will be the one that doesn't reflect the environment; to indicate this, its object Pass Index has been set to '1' - the other sphere (and all other objects) have been left with Pass Index set to '0'. The environment has been set to an HDR image.

In order to render the scene twice, we can add an additional render layer :

One render layer should have Use Environment enabled and the other should have Use Environment disabled. Ensure to enable the Object Index pass - this will give us access to the object Pass Index in the compositor.

Setup the Compositor nodes as follows :

The IndexOB is used to generate a mask to pick out the object set to Pass Index of 1 (the left-hand sphere). The two rendered (one with and one without the environment) are mixed together based on this mask so that the 'without environment' image shows where one sphere is and the 'with environment' shows for the rest of the render. The Dilate/Erode node allow you to control the blending at the edges of the transition to remove any harse artifacts.

This produces the following result with the left-hand sphere showing all reflections except the environment :


How to make an object be sensed if it is No Collision in BGE

Enable "Ghost" on the object to be sensed (Properties/Physics/Physics)


Can we skip some pre-defined Frames while rendering, to prevent blender from re-rednering the same scene?

If your output is set to be .png images (which is recommended) you can change the duration of any frame of your choice in the video editor. If you want your output to be video you can set the Frame Start and End in the Scene Tab, render the first sequence, then the frame where you want to stop, and for last render the rest of the animation. after that, you would put everything together in the video editor.


Separate objects can't be selected individually

I found the problem. It was the KIT OPS add-on every time you would copy an insert and reload the Blender file (save and reopen) the objects would be linked like that but selecting the effected inserts and pressing the "Remove KIT OPS props" button in the KIT OPS tab will fix it.


How to make this stylish «cutting mat» theme?

you can change the grid color here:

and background here:


Think of Volume scatter like smoke or dust (or murky water). If it gets too dense then you can't see through it.

Here's the same scene with different density values.

The effects of volume scattering will be more pronounced in objects that are further away, so the distance from the camera to the objects is also a factor to be considered.

Lights might not be seem bright when having to travel through volume scattering, so be prepared to use very large values for their intensity.

All lights on your scene will bounce on the volume. If you have any lights close to the camera those will tend to wash away anything else in the image (as when you drive through fog where the car lights will bounce right back):

the same scene, but with a light behind the camera:

There is no "right" or "magic" number that will work for each and evry scene, you'll have to find the one that gets you closer to what you are after...

Other considerations:

Rendering scenes with volume scattering will always result in noisier images. You'll have to increase the number of samples, which will have an impact on rendering time as well. You'll see more fireflies, created by the indirect bounces, to control use clamp indirect (a value of 3.00 is a good start point).  On the light paths bring up the bounces for volume. A smaller step size for Heterogenous volume sample helps a lot (but will increase rendering time as well).


How to get the object created by bpy.ops.object.duplicate()?

bpy.ops.object.duplicate() finishes with the duplicated object as the currently selected object. Therefore, bpy.context.object is the reference to the new object.

Ex (assume object selected in 3d viewport):

import bpy
bpy.ops.object.duplicate()

dupli_obj = bpy.context.object
print(dupli_obj.name)             #check the console

If you run this code, does it not give you what you expect?


Merging Multiple Textures on a Single Model into one Mega-Texture?

So to write up an answer, the OP needed baking.

Cycles baking is a relatively simple process as far as Blender goes, and is roughly like the following:

UV Unwrap a mesh with no overlapping Islands.
Add a new, blank image in the UV/Image Editor.

Go to the Node Editor and add an Image Texture node. Select the blank image. Do not make the image interact with the node tree in any way. Make sure the node is selected.
Go to the Properties panel > Render tab > Bake dropdown and select the following settings (for pure image textures).

You will then have an image with all the various Image Textures mapped onto it. You can incorporate this image with UV Texture Coordinates into one mega-object material.


Two armatures. Two animations. Combine into one armature with both animations intact?

Whoah I had to paste together a bunch of answers online but heres a start to doing just this:

create a new bone in the armature and use bone constraint to copy whatever attribute you need from the other armature bone. Then in pose mode, do pose -> animation -> bake action and THEN select

only selected
visual keying
clear constraints
overwrite current action - thats the one that missing from most answers online


how to Rig / Animate a Multi Lobe Camshaft

Have you considered using  Shrinkwrap constraints?
Here. the valve-rod is parented to an Empty, which is constrained to be projected onto the surface of the cam, down its own Y axis..

If the slight penetration is a bother, maybe that could be tweaked out by keyframing or driving the constraint's offset, or influence? Or by having a hidden, slightly reshaped cam, to displace the Empty,avoiding intermittent intersection with the rod.
Example settings.. the Empty is constrained to the Cam, projected.


Unwanted bump on a mesh after Boolean and Subdivision Surface

This is the kind of topology you need. It has ring-based loops of quads going around the hole.

It produces a rim with no bumps when you add your Subdivision Surface modifier.


How can I make animations look more natural?

I would suggest that you study the 12 principles of animation closely. Looking at your animations, it's obvious you're not following these; for instance, the ease in, ease out rule. Your camera motions seem to abrupt, too stable. Too unnatural.

And then practice. A lot.

I also recommend the principles of animation series by Dan Floyd from Extra Credits/Play on Youtube, where he covers these principles and show some great implementation of these in games.

You may also want to take some classes in animation, such as Animation Mentor. Keep in mind that any class about animation, even if about traditional drawn animation, will help you master 3D animation.


Basic Rigid-Body Setup: Displays perfect in Render preview but is completely broken in the actual render

The only surefire solution I have found is to select all my Rigid Body actors and then select: Object - Rigid Body - Bake to Keyframes. This ends my sim but turns everything into proper manually-moving objects that renders with no problem.


No, you can't lock a scene's layer visibility. To check layer contents, what I usually do is to reserve a separate 3D View area with its own active camera and layer visibility.

You can have a 3D View area's camera and layer visibility settings detached from the scene's by toggling off its Lock Camera and Layers button, located to the right of layer buttons:


How do I make rigid bodies use a curve guide force?

Curve guide cannot be used with rigid bodies.
As the popup window shows it is affecting only particles.

you could use a follow path constraint to get your effect.


What is the best view to sculpt in? Is it in the persective or orthographic view

There isn't necessarily a "correct" view to do anything in in blender.

However, know that in almost all cases, perspective view will be the view you will be viewing your model in afterwards, and is the physically correct way that people view the world.

Orthographic mode is really useful, especially if you want to be able to compare distances and look at a model directly from the side, but I don't usually need to do that in sculpting, so I would recommend perspective view.

If you could elaborate a little more on what you mean by "extremely hard to sculpt", I might be able to provide better advice.


Can Blend4Web Web Player be implemented with no UI?

You can create custom, non-UI applications with Blend4Web. It is convenient to use the project manager for this:
https://www.blend4web.com/doc/en/project_manager.html#creating-a-web-player-application


How to convert an edge into a curved edge?

I think we lack informations about what's the final goal, for example are you supposed to extrude, smooth, etc?

But if you want a simple flat shape, you can round the corners this way:

Delete the faces with a X > Only Faces.
Select the vertices that are supposed to be round.
Press shiftctrlB to bevel. Press + to increase the amount of segments, or do it on the bottom of the Tools panel (on the left of your 3D view).
Now fill the whole mesh with an F.
Finish the mesh with some additional vertices and edges if necessary, the knife tool is convenient for this purpose.


Got it:

obj = bpy.context.view_layer.objects.active
obj.data.override_create(remap_local_usages=True)

API link: https://docs.blender.org/api/current/bpy.types.ID.html#bpy.types.ID.override_create


IK with pole over subdivided bone chain don't bend

Yep. This is a bug with the Armature system and may be worth reporting. I think the issue is that it doesn't know which side of the bone is supposed to face the pole target.

However, if you rotate the IK bone after moving the target bone, the IK bone will snap to position, and work.

Rotate

Snap


Need help sculping wand! Using brushes seemed to be stretched horizontally

This is a common mistake on newer users.
you have to apply the  scale of the object.
to do so press "Ctrl A" and then apply scale

If you look at the side bar you can see
"Location"
"Rotation"
"Scale"
"Dimensions"

The difference between scale and dimensions is that dimensions is in real world values such as cm, m, inch, foot... While the scale is the stretching of the object.

If you press "S" in object mode you will scale using the scale values and distort the object. It can be useful sometimes but usually you should apply the scale.


In edit mode Hold down alt and right click on the circle.


How do I extract a color from part of an image and use in keying?

You just needed to scale that to the image size


Ok, After some dumb research, I find ID property who hold basic property like name.

Object *obj;
printf("%s", obj.ID.name);


You can set the speed of the physics simulation by simply changing the Speed setting in the Rigid Body World settings in the Scene tab :

Smaller values will reduce the speed (ie, 0.5 will slow it down to half-speed).


How can I enlarge selection without numpad?

Just press ctrl and numpad + three times. :)


Blender seems to extend invisible keyframes in the animation timeline

OMG...I had "Time Remapping" enabled.  I had it set from 100 frames to 250 frames.  Guess I don't know how to properly do a loop.


How do I resize a folded box without messing up the folds on the top or stretching out the squares (thus messing up mapping)?

There are many ways, a simple one is:

go in edit mode (tab)
select all edges in the base of the cube (xray mode can help you to select all the base)
G (to move the selection), Z (to block the movement only in the Z axis), move mouse to decide how far to move the base of the cube

HOW TO FIX THE UV:

fix the geometry in edit mode --> the texture is now stretched

go into UV editor, select the faces with stretched texture, go into UV editor, select the base nodes (the one that you moved to change the size of the box) and move them into the UV editor to fix the textures:


What is the popup called that appears lower left when you manipulate a mesh?

It's called an "Adjust Last Operation Panel". You can also see the name directly in the UI.

Sometimes it's also referred to as the "Operator Panel" in online discussions, however many panels in Blender's UI have operators, which makes this term ambiguous.


Blender units are actually metric.

One blender unit is 1m.

Of course you can disregard that, and model however you want, but when it comes to dealing with light falloff and depth of field in cycles or physics or fluids and cloth and other simulations, the calculations are done using blender (metric) units. In other words blender is trying to simulate those things based on dimensions, light energy and other forces in the real world.

For things to work as the tools are designed, it is recommended to make the objects as their real size would be in the real world.

Note that you can set the units (in the scene settings) to be in the scale you need: metric or imperial

For 2.8X

For 2.7X

and within those settings you can choose to work in cm, mm by changing the scale

For 2.8X

For 2.7X

Read: Can I change entire scene scale?

You can also change the scale on the viewport to make the manipulation of the geometry easier when working with very small or very large objects.


Python outputs different colors from GUI

Gotcha!
My script would pull a HEX color value and try to set it onto an RGB material node primitively without adjusting for gamma correction. The following answer helped me:
How set Hex in RGB Node? (Python)


How to convert vertex group to sculpting mask?

It's possible to achieve that with Dyntopo enabled and Mask Tools addon installed (see Installing an addon) and activated.

With addon, in Sculpt mode press Vertex Group To Mask button on the Toolshelf > Sculpt rollout.

Dyntopo allows that because the geometry needed for vertex group will be dynamically created while using Sculpt brush.
The Multires modifier isn't available for that unfortunately.


You need to define it outside of the functions to make it a property of the class. Try adding something like the following before your 'def's :
class Test_Node(Node, Base_Node):
    bl_label = "Test Node"

    #Define class-level property
    Test_Bool: bpy.props.BoolProperty()

    def init(self, context):
        .....etc.

This will define a new class-level property 'Test_Bool' and this should then be available as 'self.Test_Bool' from any of the functions within the class.


How can I get the camera's projection matrix?

With some helpful references from Campbell (ideasman42), I was able to find the relevant Blender C code that creates the perspective matrix (from properties that were actually available via bpy), and I managed to port it to Python:

def view_plane(camd, winx, winy, xasp, yasp):
    #/* fields rendering */
    ycor = yasp / xasp
    use_fields = False
    if (use_fields):
      ycor *= 2

    def BKE_camera_sensor_size(p_sensor_fit, sensor_x, sensor_y):
        #/* sensor size used to fit to. for auto, sensor_x is both x and y. */
        if (p_sensor_fit == 'VERTICAL'):
            return sensor_y;

        return sensor_x;

    if (camd.type == 'ORTHO'):
      #/* orthographic camera */
      #/* scale == 1.0 means exact 1 to 1 mapping */
      pixsize = camd.ortho_scale
    else:
      #/* perspective camera */
      sensor_size = BKE_camera_sensor_size(camd.sensor_fit, camd.sensor_width, camd.sensor_height)
      pixsize = (sensor_size * camd.clip_start) / camd.lens

    #/* determine sensor fit */
    def BKE_camera_sensor_fit(p_sensor_fit, sizex, sizey):
        if (p_sensor_fit == 'AUTO'):
            if (sizex >= sizey):
                return 'HORIZONTAL'
            else:
                return 'VERTICAL'

        return p_sensor_fit

    sensor_fit = BKE_camera_sensor_fit(camd.sensor_fit, xasp * winx, yasp * winy)

    if (sensor_fit == 'HORIZONTAL'):
      viewfac = winx
    else:
      viewfac = ycor * winy

    pixsize /= viewfac

    #/* extra zoom factor */
    pixsize *= 1 #params->zoom

    #/* compute view plane:
    # * fully centered, zbuffer fills in jittered between -.5 and +.5 */
    xmin = -0.5 * winx
    ymin = -0.5 * ycor * winy
    xmax =  0.5 * winx
    ymax =  0.5 * ycor * winy

    #/* lens shift and offset */
    dx = camd.shift_x * viewfac # + winx * params->offsetx
    dy = camd.shift_y * viewfac # + winy * params->offsety

    xmin += dx
    ymin += dy
    xmax += dx
    ymax += dy

    #/* fields offset */
    #if (params->field_second):
    #    if (params->field_odd):
    #        ymin -= 0.5 * ycor
    #        ymax -= 0.5 * ycor
    #    else:
    #        ymin += 0.5 * ycor
    #        ymax += 0.5 * ycor

    #/* the window matrix is used for clipping, and not changed during OSA steps */
    #/* using an offset of +0.5 here would give clip errors on edges */
    xmin *= pixsize
    xmax *= pixsize
    ymin *= pixsize
    ymax *= pixsize

    return xmin, xmax, ymin, ymax

def projection_matrix(camd):
    r = bpy.context.scene.render
    left, right, bottom, top = view_plane(camd, r.resolution_x, r.resolution_y, 1, 1)

    farClip, nearClip = camd.clip_end, camd.clip_start

    Xdelta = right - left
    Ydelta = top - bottom
    Zdelta = farClip - nearClip

    mat = [[0]*4 for i in range(4)]

    mat[0][0] = nearClip * 2 / Xdelta
    mat[1][1] = nearClip * 2 / Ydelta
    mat[2][0] = (right + left) / Xdelta #/* note: negate Z  */
    mat[2][1] = (top + bottom) / Ydelta
    mat[2][2] = -(farClip + nearClip) / Zdelta
    mat[2][3] = -1
    mat[3][2] = (-2 * nearClip * farClip) / Zdelta

    return sum([c for c in mat], [])

This call: projection_matrix(camera.data) will return the perspective projection matrix of the given camera object.

I don't know what the "fields" data is supposed to be, so I've set use_fields to False, and I didn't port the "fields offset" block (which you can see commented out, in view_plane function). Regardless, the resulting projection matrix seems correct, so I guess it's not all that important (for most people).


Volume scatter shader causes black spots

These are caused by self-intersecting bits of the cloud particles showing the backsides of faces to the outside world:

Rays going through the back of a face don't count as going into the volume, and so appear mostly transparent.
To fix this you have a couple options:

Lighten up on the displacement to avoid such intersections:

Or add a remesh modifier (and optionally a decimate modifier to keep the vertex count down)


Select Pose Bones Per Script In Blender 2.8

Select the armature bone.
Further to the answer by @yhoho a pose bone has a bpy.types.PoseBone.bone property pointing to its associated armature bone.
Example from python console (where C = bpy.context) , bone of interest has name "Bone", armature object has context.
When unsure of things the python console is a handy way to interactively see what's what
>>> C.object
bpy.data.objects['Armature']

>>> pb = C.object.pose.bones.get("Bone")
>>> pb
bpy.data.objects['Armature'].pose.bones["Bone"]

its associated armature bone, from its bone property
>>> pb.bone
bpy.data.armatures['Armature'].bones["Bone"]

Which tells us could also get this via the armature, ie the data part of the armature object.
>>> arm = C.object.data
>>> arm
bpy.data.armatures['Armature']

>>> bone = arm.bones.get("Bone")
>>> bone
bpy.data.armatures['Armature'].bones["Bone"]

The two bones referenced in different ways are equal
>>> bone == pb.bone
True

but are not an instance of same object,
>>> bone is pb.bone
False

A bone from the armature bones collection of type bpy.types.Bone has a select property, whereas a pose bone bpy.types.PoseBone  from an armature objects pose bone collection has not (AFAIK never has).
Hence as shown to select, can use either of
pb.bone.select = True
bone.select = True

The idea of using collection.get(name) is that it returns None if the named item does not exist and can be checked against None (boolean False)  and handled.
>>> pb = C.object.pose.bones.get("NonExistentBone")
>>> pb is None
True

Related
Set active bone in pose mode from Python script


UV unwrapping of a row boat is not working

Have you tried this:

Change from Render Results to skiff-side.jpg


blender symmetries are weird. It works strangely

If I am not mistaken, your object origin has moved. Try resetting it.

Enable "Affect Only Origins option" (see image)
Select your object in object mode and hit Alt+G to reset its transfrom

Or

Shift + C to reset cursor.
right click -> set origin -> to cursor


glTF is a GPU-ready format that only supports meshes, not other types of geometry directly.  To make the text compatible with glTF, look for the convert option in the Object menu of the 3D view:

Object -> Convert To... -> Mesh from Curve/Meta/Surf/Text

If needed, make a copy of the text beforehand.  Once converted to a mesh, you won't be able to change the font or letters used, but you can apply normal mesh modifications to it.


Is there a way to check a mesh for problems?

There's an old way. In edit mode, select nothing with A and then hit ctrl alt shift M to select non manifold verts or edges. These are edges that do not have exactly two faces connected to them. If nothing gets selected, your mesh is pretty solid.

Try it with vertex select or edge select. Both modes provide insight.


Why am I unable to change opacity of background images in Blender 2.82 (sub 7)?

In order to change the opacity level you have to turn on Use Alpha. In your screenshot it's the third field from the top.


Interactive 3D House Interior in Blender

If you're using Blender < 2.7x you could do it with Game Engine.


A quick hack is to run a rigid body simulation until you arrive at a frame which looks right. Writing a script to get what you need can be a bit of a puzzle...


You should delete them and create nice geometry by bridging the edge loops instead(Ctrl+E -> L):

This way you will avoid possible shading errors with automatic triangulation of concave n-gons. You can then select the face loop by Ctrl+ click, or select one face and hit Shift+G->C for selecting Co-planar faces, or you could use select linked flat faces function:

You could assign a shortcut to that by rightclicking it and choosing assign shortcut.


Is it possible to deselect freestyle edges?

In Edit Mode select the edge and Mark Freestyle Edge Ctrl+E,F
In the Properties window > Render Layers > Freestyle Line Set:

Enable Logical AND.
Enable Edge Mark and the (Exclude Edge marks) X button next to it.

Result:


How to share shaders among different materials

Textures are assigned by face, to make the ocean all one texture you would need to make one for the ocean, then make all ocean faces that material. If your contents were on one texture with the water areas alpha, then you could make one for the ocean, then overlay the contents over the ocean.
It may not be hard to edit your map image in a program to make an image with the contents and alpha water.


I would do it manually:

Put your picture as a background image.
Create a plane, begin to follow the shape of the object with some extrusions.
When you have finished, create some edge loops on the centre of each quads line, where the bump is supposed to happen.
drag the edge loops to create the bump.
Give your object a Subdivision Surface modifier, and click the Smooth Shading button to smooth it.


Is there a way to bake materials/textures, that use nodes, into materials/textures that can be used in the game engine?

Nothing really changes from a rectangular baking tutorial to anything else except for the UV mapping. Try using "Smart UV Project" to unwrap a complex object quickly, then go through the baking steps.

Add the image texture that you want to bake to in all of your materials (on the object that you are baking).
Setup the bake settings (depending on what you want to bake), then hit the bake button.
Save the baked image.


Changing the default object origin from center to corner?

As far as I know there is no built in way of doing this natively, at least not without some python coding or script/addon involved.

There is one addon for aligning objects that has an additional feature that allows you to align object centers directly from object mode though.

It doesn't do it automatically but maybe it can save you a few steps http://blenderartists.org/forum/showthread.php?256114-Add-on-Advanced-align-tools


Sudden crash after render finished - no image, no logs

The solution:

My own question (process between rendering and writing) led to the solution. Actually, there was a "SurfaceDrawing-Something" in the scene. Must have been a mistyped sculpting action. Whatever it is, it invokes a postprocessing which obviously is very hungry at some 30k resolution.

So watch out for strange elements in the outliner!


I guess you are using a Sun lamp? Have a look at the Max Distance under the Cascaded Shadow Map.


The issue is, as @TARDIS Maker pointed out the sub surf modifier that you applied to the dice object. Its effects are being applied to the text. To rectify this you can add a mean crease to the text to prevent the sub surf from taking effect. Select the vertices that make up the text and use Shift-E then 1. This will make your text appear exactly as before (Unlike holding edges which will cause minor rounding) with the added benefit of not having to apply the modifier (Maintaining a non-destructive workflow).


How can I 'stamp' a fingerprint onto an object's geometry for 3D printing

I would think displacement is the way to go. An alternative would be to try making a textured sculpt brush with the texture set to stencil and use Dyntopo.


Simple infinite terrain concept BGE, HUGE drop in frame rate on spawned land

I actually solved my own problem. I had never used the near sensor to spawn an object before so I didn't realise it will constantly spawn a new object every time you move within the sensor's range. So, I simply added an "end object" actuator to the empty below the "add object(landmass)" actuator. This ensures a landmass will only ever spawn once and not spawn again if the player returns to the area.

If anyone is wondering what method I used for the spawn setup: I have each square landmass in a second layer with 3 empties on every side except for one (the one "player"[property] just came from) with a distance 1.5x the landmass width from the center of said landmass. I then simply have each empty rotate the correct 90 degree interval to spawn the new landmass in the correct orientation.


How do I get the edges of the Manhatten Voronoi texture?

You can output it to a ColorRamp to get this kind of effect :

Note that the interpolation is set to Constant, to get a clean sharp edge.
Instead of the ColorRamp, you can probably use some Math nodes for a more controllable effect.


Reflections do not show in imported model

The model contains only one material. If you want the windows to have another one, go in the material panel and add it (see below). For this example I've set it red. I've done it using Blender Internal but for Cycles this is exactly the same principle (you'll simply need to setup the material with nodes).

Now you need to associate the wanted faces to this new material.
Enter edit mode, select the faces, choose the material and click "assign".

Here the windows are composed of four layers (probably for security reasons:). So to access the layer behind I hide the first one with H.

Once done, use AltH to make hidden parts reappear.


No need to subdivide the whole plane, no need to add vertex groups or modifiers!

All you need is Ctrl+Shift+B and middle mouse button scrolling on vertex or vertices:


Assigning weight

Add Vertex Weight modifier, create empty vertex group, enable group add and tweak few sliders to get it work.

Selecting vertices

Add Mask modifier and select same group as in Vertex Weight modifier. Also enable all display options to see modifiers working in edit mode (inside green box on screenshot)

Next, you enter edit mode and select everything. Press A twice to toggle selection. It is mandatory to select all NOT by pressing A, use selection tools instead (like border B or circle C) with wireframe view  enabled Z to speed up things a bit. Once you have select everything, assign it to new vertex group.

To check if you done it right, disable viewport visibility of modifiers.


How to reset all settings and get back initial blender setings?

In a 3D ViewPort, press Spacebar, then enter 'load factory'. You'll see an operator called 'load factory settings'.

When you execute that, you get the Default Scene back, and the settings as well. Remember to save your user settings now by going to the User Preferences, and hit 'Save User Settings', as well as hitting Ctrl + U in the 3D Viewport and save the startup file.


Move a set to another scene even though it’s done

Just create a new scene.

(source: blender.org)

You can then choose to link or copy your assets

(For 2.8)

(blatant quote from the blender manual)

  New

  Creates an empty scene with default values.

  Copy Settings

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

  Link Objects

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

  Link Object Data

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

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

  Full Copy

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


This is probably because some parts of your model have a material and some parts don't. Though if they all do/ don't have a material then one thing you could do is manually set the viewport color for the model as seen in the screenshot.


Thx to @batFINGER, here is the code that works (@ is important for multiplying Quaternion and Vector in Blender 2.8):

rot = bpy.context.space_data.region_3d.view_rotation

# Instead of adding it to the vector that is returned by region_2d_to_location_3d
# I pass it to the method as last argument
dir = rot @ mathutils.Vector((0,0,-1))
dir = dir.normalized() * -2.0

vec = region_2d_to_location_3d(region, rv3d, (x, y), dir)


Remove reflection of one object from another object?

Cycles:

Set the renderlayer with the reflective object to Exclude layer one:

Now objects on layer 1 will not have any affect on layer 2.

Example .blend

Blender Internal:

In BI this is more complicated, because it appears to be impossible to separate reflections into separate layers with BI.

In other words, you can either reflect every object in the scene, or reflect nothing (no selective reflecting). You might be able to do something with the Material Index pass, but with even a simple scene it becomes complex quickly.

As a workaround, you can use multiple Scenes.

Create a new scene in the Info panel by pressing the +:

Select one of the options. You probably want Link Objects, but check the wiki for an explanation of each option.
In the new scene, setup a renderlayer that only renders objects on layer 1.
Back in the first scene, setup a renderlayer which has only the reflective object. Put objects you do want to reflect on a different layer, but in the same scene.
Mix the two scenes with an Alpha over node:

Example .blend


Are Displacement maps used to create normal maps?

One point to true displacement is that some people use higher poly counts than you do.  All the way to adaptive subdivision, which might make a vertex for every screen pixel.
Even at low poly counts, they're useful for low-resolution displacement.  You don't need ten million vertices to turn a height map into low-poly terrain.
That doesn't mean they're useful to you.  Blender has all sorts of tools that are only useful to some people.  In years, I've never bothered to learn how to do camera tracking, for example.
Yes, you can use a displacement map to make a normal map.  Simply use your displacement as the input to a displacement node in your material, then bake your normals.  This is not the only way to make a normal map, nor is it the only thing one can do with a displacement map.
Displacement maps are useful as bump maps without baking as well, because they deform fine without relying on UV tangents, which allows you to use them on deforming meshes with arbitrary meshes and UV maps-- even without any UV maps at all.


What's the difference between 'unlink' and 'remove' from collection?

If your object is linked to more than one collection Object > Collection > Remove From Collection will give you the option to remove it from all collections or from one specific collection. Unlink in the outliner on the other hand only removes the selected object link from the collection it is in. If the object is linked to other collections, these will remain.


Use compositing nodes in blender to for pixel image processing.  We  used a

[Separate RGBA Node] and selected the R .. Red Channel.

Create an image sequence if that suits you.

In the image above we used a 3D scene with red and green object.
In the compositing node view.  We view the red channel as intensity gray ...for red ball.  The green ball appears as black. I have clicked on a particular node to change the backgroud image of the nodes.
In the lower left is a file input if that suits you for a image on your hard disk.  Otherwise you could map your images onto a plane.
I did not connect the file composite output ... so I could have many images in one screen shot. Connect the image you want to the final output.
There are many good videos on a video site such as youtube as a random example. Search Blender Compositing Nodes.  Once you see a video these nodes will seem simple.  Please excuse my noodle soup.


Why does my model turn into a mess when in object mode

Hidden faces

You have set some faces as not visible in edit mode. The fact that they are hidden is true only for edit mode; in object mode you'll see all the faces (unless you specifically  set up a mask modifier).

You can see the whole object by un-hiding the faces with the Alt+H shortcut while in edit mode.