water simulation -Move water upward along a slope

In the Scene settings, switch off Gravity by unticking the checkbox. This will enable the Gravity settings in the Fluid Domain Settings. You can then adjust the gravity such that the 'uphill' becomes 'downhill' and the water naturally flows uphill.
Note that this depends on the topology being such that the water will naturally flow in the desired direction - eg, up an indented riverbed. If the situation is more complicated you may need to resort to other methods to 'Guide' the water along the path but this would risk making the motion less natural.


"cursor_location property cannot be animated" error in Blender

Where in Blender UI is your mouse cursor hovering when you press the I key?
Are you by any chance hovering the 3D Cursor Position coordinate boxes?

You seem to be trying to animate the 3D cursor position, which apparently is not animatable. As far as I know it is part of Blender UI data or temporary run time data, I think, not a property from your scene, and thus not a type or data that can be stored or animated.


What's the data_path of lamp energy? BUG?

Of the three choices my bet is that you're doing it wrong in that your o object is the lamp object, not the data part, or some other non LAMP data object.

import bpy
context = bpy.context
#o = bpy.data.objects.get("Lamp") # assumes you have an ob named Lamp
#o.data = bpy.data.lamps.get("Lamp")
o = context.active_object
if o:
    #o.energy
    print("%s (%s)" % (o.name, o.type), getattr(o, "energy", "Has NO energy property"))
    o = o.data
    #o.data.energy
    if o:
        print("%s (%s)" % (o.name, o.type), getattr(o, "energy",  "Has NO energy property"))

If you grab a datapath from the DATA Properties panel, eg mesh panel for mesh objects, the datapath will be resolvable on the data part.
context.active_object.data  (except for empties, whose data part is None)


How can I create a box/cuboid by entering values?

It would be better to set the dimensions of your object, like in the screenshot. This way, you can even make use of blenders ability to use different units. After that, apply the scale of your object. This will normalise the scale while keeping vertices at the right position, and prevents many problems later on, especially if you plan to animate.

There is another way to achieve what you want: At the moment, you added the new object to your scene, there're some parameters to change - see screenshot. Sadly, this is only possible directly after creating the object. Blender creates objects and treats them as meshes directly after, while 3ds Max creates primitives, which can be edited with edit poly later. Both ways have their drawbacks.


That is the number of Particles PER Face, expressed like a ratio.
If you leave it at 0 it emits whatever number of particles per face it wants, based on the total number of particles you defined on the fields above.
If you set it to any other number, then that exact number of particles will be emitted from each face, regardless of how many total particles there are.


Will EEVEE be able to do real time ray tracing?

Not in a soon future. NVIDIA's GTX 20 series cards have the ability to do some real-time ray tracing but it's not enough for doing seamless rendering for any scene with high FPS (frames per second). Although, as mentioned here people can use these new graphics cards for renderings using EEVEE or Cycles but Blender is not able to take the advantage of the ray-tracing capabilities of these cards. However, based on some discussions I've had with Blender developers I know that they are considering using NVIDIA's APIs such as OptiX in the future. OptiX is backed by some advancements in AI that allows extremely fast denoising/approximation of ray-traced scenes with only 1 or 2 ray bounces instead of couple of hundreds or more. This way, you can get to pretty high FPSes (e.g. 60 or more) without the need to perfectly track rays for many bounces in the scene. Keep in mind that this is the first series of GPUs being able to perform many ray-tracing operations per second. This will only get better in the future with newer GPUs that will be capable of doing orders of magnitude more ray-tracing operations so that you won't need to do that much of approximation for the final scene rendering.


Cant export correctly from blender to unity because of the mirror modyfier

From the appearance of the backwards car in unity, I would say your normals are oriented backwards and thus only viewing faces from the inside causes them to appear. Recalculate the normals outside.


Texture stretching at edge even though UV map says it's fine

The distortion in your unwrap may be caused by:

modifier options: some modifiers (e.g. solidify) can add som distortion to your unwrap
geometry errors: for example duplicated vertices or overlapping faces
uvs are not relaxed enough

So, first of all check your geometry. If your model is perfect, then you have two options:

unwrap again the faces which have the distortion
pin the borders of your shells and update the uv coordinates (a pinned vertex will keep it's position also if you try to unwrap the entire model)

I would suggest to apply the last option, and to do that:

in UV/Image Editor select the border edges of your shells and press P to pin these vertices (now are red colored)

select all the shells (with A for example) and then press E, so you will update the uv coordinates for all vertices except the pinned ones


Rotation animation isn't fixed on the pivot point

You can either change the pivot point as moonboots suggests, or (if you need the pivot point to stay elsewhere for other reasons) you can

Add an Empty on the desired axis of rotation

Select the door, then Shift+Select the Empty, and CtrlP Set Parent to Object
Animate the Empty, not the door

(this is a very common procedure for rotating a camera around a scene by using an Empty)


Is there any way you can post some images that display the problem? I can't duplicate it.

Scale with Median selected:

And then with Individual Origins selected:

Rotate with Median:

And Individual Origins:


started making character with his pose, now mirror doesn't work properly

Reset your scale and rotation with hotkey Ctrl + A  before you start sculpting.


So if you're trying to limit the rotation between the 2 lowerarm bones, what you're looking for is probably the IK Limits: In Pose mode, select the bone you want to constrain, go in the Properties panel > Bone > Inverse Kinematics (this menu appears as soon as the bone is influenced by an IK), then limit on the axis you want, in that case X and Z.
As you mentioned, in 2.8 you can simply click on the Lock IK option (top of the same menu).


Another option is to surround your scene with a cube and give it a Volume based on a Volume Scatter node, with it's density controlled by the Z-Depth or View Distance output of a Camera Data node. In the example below, I used "multiply", as this gives the best generalized effect, whereas, "add" will make the fog "fill in" the caverns as the camera scrolls out. Have a try with both if you like.

This is the scene in solid mode:

As you can see, all I did was surround the scene with a cube, remove the surface color from the cube, and connect the Volume Scatter with a low density (governed by the Math nodes)


Can we use the shape of an object that is instanced to particles with dynamic paint

Dynamic Paint isn't necessary for this to be done.

Gleb Alexandrov recently posted a video showing how to use a cloth simulation to achieve damage on an object which matches the shape of the object that is colliding with it as shown here in his video Blender Tutorial: 9 Ways to Destroy Things  https://www.youtube.com/watch?v=wJFE2pb0Ri4

Fist step: add a cloth simulation to the object that you want to have a worn-down damaged look.  To have the object become squashed without bouncing around or flattening out, just set 'Bending' to 0.0

Then you add a collision simulation to the object that will be causing the damage.  I used default settings for this.

Now use the Timeline to animate the damage-causing object to overlap with the cloth simulation object that is to receive the damage.


Convert OBJ files to FBX files pros and cons

you have to understand that .obj files and .fbx files are following different concepts.

The .obj file format is a simple data-format that represents 3D geometry alone. In other words, its a simple text-based file that is primary for storing Meshes.

And a .fbx file format (and collada file as an open source equivalent) can store whole scenes (Camera, Armatures, Meshes, Curves, Empties, Lights, etc).

An .obj file can store:

Meshes information (Vertices, Edges, Faces) in multiple objects
Normals
UVs
Object information like Position, Rotation, Scale (in relation to each other!, I've often found that the obj exporter created files which had different dimensions in Blender to Meshes that had the same bounding size after importing to a different engine (Please correct me if I am wrong)
Some basic material information in a Separate .mtl File (nothing like complex cycles nodes)
Some Programs(Zbrush, XNormal, not Blender) can read and write Vertex colors to the obj file
It is possible to create .obj animations and some engines are even capable to read them. But you have to know that blender creates for every frame a new objfiles. So, most of the time, nothing you would like to have in your realtime engine

As mentioned above, a fbx file can store a lot of things.  Essential is what your exporter(Blender) and your importer (Game engine) is capable of reading and writing.

I definitely would recommend to use fbx or collada for any kind of exchange. I had significant problems with obj.

to answer your questions:

  What happen with normals projections from the mesh in the conversion from file to file?

Normals should be the same in every file format

  Is it the same type of mesh (collada, mesh, etc.)?

Yes, it is the same type of mesh.

  Is it a good idea to convert obj to fbx for animations for use in an engine?

Definitely

  I create the maps, go back to Blender and see the results, but when I decided to export the whole model with textures an animation, I change the OBJ to FBX.

What you do in the process of creating your models doesn’t matter. You only want to prevent data loss. Obj is ok for texture generation with XNormal. Fbx is also ok.


Right click on them and reset everything. It works in both render engines.


How to rotate a 2d plan in ver 2.79. no option in propert panel

Assuming you have a blueprint which contains sections with both plan and elevation views, you can assign the same image as background to each relevant Blender orthographic view.

For example: Having constructed your shell from the blueprint's elevation section in the Blender's 'Left' view, you can add (Add Image) and assign the same blueprint image to Blender's 'Top' view. You don't have to reload it from file, it will already be in Blender's list of available images. You then offset/ rotate/reflect the blueprint image (in the Blender's background image panel) so that its plan section coincides with the shell you have built, seen from the top.

The versions of the background image are visible only from the exact preset Blender view to which they were assigned.


If only I could get more details as to what exactly you expect from the software, I might be able to answer your question right.

However, from you explanation, I replicated that, and I'm not seeing any problem.

What version of blender are you using? You built from source or downloaded from blender.org?

I just set my transparency to the desired value in the materials tab in the properties panel and all seem to go well.

By the way, I used the bge too.


How to fix mirroring issues? Trying to mirror but object rotation is wrong

The Mirror modifier uses the object's local orientation, you must have rotated the object in object mode, so its local orientation is not aligned with the global orientation anymore. If you want the Mirror to be aligned with the global orientation, apply the object's rotation with CtrlA > Apply Rotation.


You can use a stretch to constraint, pointing from the foot to the hand bone.


sharp corners after subdivision modifier

figured it out...
forrest through the trees...
internal faces at the junctions...
but the next question is how to remove about a thousand of these faces...?
at the moment I am having to isolate each junction pull it up on edit mode, remove the faces, then repeat.


How do I achieve a bending effect with the collision of two rectangles?

Here is a way to do it with the Mesh Deform modifier:

Create your block A, subdivide it, give it a Subdivision Surface modifier.
Create a second block, B, with the same kind of subdivision, and that contains A. No modifier for this one, but in the Properties panel > Object > Display > Choose Draw All Edges and Maximum Display > Wire. Now B should only show its wire.
Also, for B, in Object mode, in the Properties panel > Data > Shape Keys, create a first one, called Basis by default, then create a second one.
Give A a Mesh Deform modifier, put it above the Subdivision Surface modifier, choose B as the Object, and click Bind.
Select B, make sure that the second Shape Key is selected, go in Edit mode, and change the shape of the mesh as you want. A should be deformed.
Now animate as you want (study how the Shape Keys are running if you don't know enough about it).


How to convert physics animation to a curve/path?

One method of converting a motion into a path is detailed in How to add trailing light effect to finger tips - by adding a particle system to drop particles as a vertex moves through space and then running a script to convert that particle system into a path. I also created an add-on as part of this answer to make the process easier.

The add-on can be downloaded from here : Particles To Path add-on

Once you've installed and enabled the add-on and you have your trail of particles (disable gravity and interactions from your particle system and have it emit a single particle for each frame of the animation) you simply execute the Particles to Path function (press Space (Blender 2.79) or F3 (Blender 2.8) and start typing the name) :

This should then generate the required path which you can use for your Follow Path constraint.


Blender 2.8 - can't see objects outline on default mode

You have to set the viewport overlay to outline selected:


Bone moves completely instead of rotating on axis

In edit mode enable the connected check box as depicted below.


Emissive shader does not change much in changes of orders of magnitudes

The problem is the light clamping setting.

Set "Direct Light" to 0 to fix the power issue.
Setting the clamping to 1 means that any value brighter than 1 is clipped (or ignored), therefore it doesn't matter if the lights are set to an intensity of 1 or 1 million. Setting it to 0 means that the lights are un-clamped, therefore using their real values.
Read: What is Clamp Direct/Indirect?
Additionally, I would recommend setting the color management to filmic for more realistic tone mapping. Standard transform is usually used for video editing.


Blender file taking over an hour to load, is this normal?

10m vertices in a curve are a lot, especially since a bezier is subdivided even more between its control points. With a 2D curve, the filled shapes have to be calculated; another unoptimized step.

Some ideas.

Simplify the svg before exporting (in the exporter application).
Separate the svg in object mode. F3 > "Separate" [search]
Reduce the Preview Resolution of the curves.


How to create parallel edge between vertex and edge?

the Toolpanel (t-key) have no Join tool maybe you lock for.
But operator exist in the edge or vertex menü to solv your problem.
Mouse rightclick brings  a compact menü with operators
but depense on the select modes you choose (vertex,edge,or face) .
and left click or rightclick 2.8 Mode you use and  choose .

It could be that joining from a vertex to edge needs extra steps or actions.

So.
Select the edge thats needs the conection  with
 activ 'edge select Mode '.
and then
rightclick with the mouse and  look and  click on  the  edge Menü operator

'subdivide edge'.

This subdivide the  edge  and creats one new vertex in the middle of your selected edge .

Now use the vertex select Mode.
Select the  new created vertex on your edge  hold shift key and select the second vertex .
rightclick with mouse and find i
n the vertex  menu operator    called 'Join " .
That it.
a new edge conection between your vertex and edge(new vertex) is created that flows like you want.
Wfg


When you press the 1 key in object mode, it hides all the collections except the first one. Likewise, if you press 2 it will hide all the collections except for the second one, and so on.
To unhide a collection click the eye icon to the right of the name of the collection.


It is possible to add modifiers to a group?

Modifiers can be easily added using python.

target_lattice = bpy.data.objects['Lattice']

for obj in bpy.data.groups['Group'].objects:
    new_mod = obj.modifiers.new(type='LATTICE', name='Lattice')
    new_mod.object = target_lattice
    new_mod.strength = 0.5

Instead of all objects in a group you can use the selected objects with bpy.context.selected_objects

By changing type='LATTICE' you can add any modifier you want. Each modifier has different property names which can be seen in tooltips when python tooltips are enabled.


Rigify addon does not do its job properly for my character

Your face is working badly because your head hasn't a good topology. Search (even in this site) for Head topology and edgeflow, or start trying to copy this example of good head topology.


a quick time+poly saving trick (Remove a section of Edge Loop)

To remove this edges and keep the faces , do the selection and hit X then choose Dissolve Edges  :


Not being able to rotate or scale in blender 2.79

with the item selected in object mode hit "n" opening the tool shelf and showing the transforms. See if the padlock by the problem transforms is closed. if so click on it to unlock it.


I have a camera solver on a camera, how can I delete the solver on a duplicate camera and keep the rotation and location the same?

Convert the tracking information to keyframes.
On the selected camera, open the camera solver constraint and click on convert the constraint to f-curve

Motion and rotation of the camera will be converted to keyframes.
https://docs.blender.org/manual/en/latest/animation/constraints/motion_tracking/camera_solver.html


Relationship between the sensor size and focal length

The focal length doesn't change with sensor size. A lens with a 35mm focal length is always 35mm. However, the FOV changes for the same focal length with different sensor size.

The reason for the common misconception that the focal length gets longer with a smaller sensor, is that lens and camera manufacturers often (if not always) tell us that for instance "This 50mm lens on this camera is equivalent to an 80mm lens on a 35mm sensor". What this means, is that on a Canon APS-C sensor1 a 50mm lens gives the same FOV as an 80mm lens would on a fullframe 35mm2 sensor.

Crop factor on Wikipedia explains it quite well.

1Nikon has a different crop factor, so a 50mm lens on one of their cropped sensors would be equivalent to 75mm on a fullframe.
2A fullframe 35mm sensor is actually 36mmx24mm. 35mm comes from the fact that film is 35mm wide, including the edges above and below the recorded image.


Convert a curve to a mesh with a user defined resolution

Bezier Curves

The curve resolution is already an exact parameter that drives the resolution of the surface (for example in U direction), but it is taking into account the number of faces, not vertices.

For a curve without V resolution (0), the faces collapse into edges, so you'll have a starting vertex, than an edge(1) followed by a vertex (1), than an edge(2) followed by a vertex (2), ... than an edge(n) followed by a vertex (n).

At the end the number of vertices is always n+1, with n as the number of edges/faces resulting from the moltiplication of the resolution and the number of segments of your spline.

The following example consider a spline made of 1 segment (2 control points). See how in this case the resolution is equal to the number of resulting edges.

The final formula should be:

  n° of final vertices = n° spline segments * resolution + 1

Nurbs Curves

Nurbs have a different mathematical implementation from Beziers.

They require at least 3 control points to build a proper geometry. If you set the Resolution parameter to 1, you can see how the number of edges constituting the figure is equal to the number of control edges minus 1. But as the number of final vertices is equal to the number of final edges plus one (as seen before), we can say that the numberof final vertices is equal to the number of control edges that the Nurbs has.

So for example a Nurbs curve made with 5 control edges, will result in a curve with 5 vertices once converted to mesh, if the resolution is set to 1.

As the tooltip says, the Resolution Parameter controls the number of subdivision per segment. Here's a few result for the previous example:

Res: 1 -> 5 vertex (4 edges)
Res: 2 -> 5*2 = 10 vertex (9 edges)
Res: 3 -> 5*3 = 15 vertex (14 edges)
Res: 4 -> 5*4 = 20 vertex (19 edges)
....
Res: n -> 5*n vertex (5*n-1 edges)

The final formula should be:

  n° of final vertices = n° of control edges * resolution


Child object moves and rotates upon parenting to bone

Let the bone position it, then tweak.

In as much as you can position then parent, I am suggesting the opposite. The nature of parenting is to let the child inherit the transform of the parent.

If the object has no translation or rotation it will be at the location and rotation of its parent.

The head to tail axis of a bone is, +Y along the bones length. Align our child object to reflect this.

The "up" axis of our default cone is +Z, we want to make it point to "+Y".

The default cone, rotated and translated such that its origin (local  (0, 0, 0)) is  at the tip of cone, and it points in a +Y direction.  The cone is at global location (0, 0, 0)

If non-zero rotation apply the rotation.

Now we can parent to a bone and the cone will be tip to tail of bone.

cone parented to head bone of rigify bird metarig, adjusting the cones y location will slide it up and down the bone


boolean modifier removing the exact opposite of what i want it to?

You select the box, go to modifiers -> add boolean modifier.
As object you select your text mesh.
Choose intersection.
Apply.
Delete your text.
Ready.
If this was too fast, checkout my tutorial video:
https://youtu.be/Zshq7pk8Psg


Scaling and importing from blender to unity

A Blender unit is per default 1m. You can display this in edit mode by the Edge Info checkbox the units can be enabled in the Scene Tab.

In order to import it correctly into Unity drag and drop the .blend file directly to your asset folder in unity, materials will be automatically created. Textures need to be imported and assigned manually to the material slots.

Behind the scene Unity runs Blender and does an .fbx export. You could also  export the model manually. File -> Export -> .fbx for more control:
Note that the export dialog provides settings to scale and change orientation of the used coordinate system:


Why this script doesn't run as expected?

Set the active object with

context.view_layer.objects.active = obj

The active object can be active and unselected.


Is there a way to turn Duplifaces (Instansing in version 2.8) into a mesh?

In object mode select the parent object, press F3 to access the search menu and type "make instances real".
Or in the menu look for Object>apply>make instances real. (or press ⎈ Ctrl+A and select Make Instances Real)

Form the blender 2.8 manual

Make Instances Real creates a new object for each instance generated by the selected ones, and removes any direct instancing from those.
In the end, each instance becomes a real object.


Weird rectangular artifacts when using Radeon ProRender

I got the problem that looks pretty much like yours. Sounds stupid, but i fixed it by simply upscaling number of samples to 256. System specs: i3 8100, rx580 4gb 16gb ram windows 10 pro 1909.


How do I know the parent of my selected object?

You can read this information in the properties panel, Relations tab.


Create a single object with a single texture from blend file including several materials

Blender internal and cycles do not use the same materials. You can bake a cycles material to an image texture and then create a blender internal material that uses that image.

Also look at the texture atlas addon to merge all objects onto one image texture.


Render pixel color information in the Image Editor

In the image editor, hold down right-click on the image. Pixel stats will appear on the bottom of the window. This tool also works while the image is still being rendered.

Here is a demo (Notice the bottom):


One option would be to use select random and then run a script that deselects anything that doesn't match the name that you specify.

import bpy

for o in bpy.context.visible_objects:
    if 'gizmo' not in o.name.lower():
        o.select_set(False)

Another way could be to make a list of objects matching the name criteria and then getting a random choice from that list and selecting them.

import bpy
from random import choices

bpy.ops.object.select_all(action='DESELECT')

objlist = [o for o in bpy.context.visible_objects
            if 'gizmo' in o.name.lower()]

rand_list = choices(objlist, k=int(len(objlist) * .75))

for o in rand_list:
    o.select_set(True)

In this example, I set the k parameter to be 75% of the object list. You could also specify an exact number of objects that you want selected.


How to get unique displacement for each particle object?

I came across ParticleInstance modifier. I'm not sure if this is the best way to do it but it seems to work.

In the particle system settings, render as object and use Empty:

Add a ParticleInstance modifier to the actual object and place it before the Displace modifier. To use the size randomness, enable the Size option:

Edit. Actually the 'Render As' option of the particle system can be None. Just temporarily set it to Object to set the Scale and Scale Randomness. Then set to None, or just don't select anything in 'Instance Object'. There's no need to multiply all the Empty objects.


Some curves ignore the curve resolution, Active Spline field missing settings

Solved with the help of StrayBillie from the BlenderArtists forum: I fixed my curve by selecting it then pressing F3 and looking for Curve - Set Spline Type - NURBS. I wasn't aware of the different spline types till now.


Need Technique for Projecting Countries onto the Earth

You could:

Select all you countries and join them with CtrlJ
Create 2 grids (delete faces only, keep the edges), one for the front, the other for the side view:

Select one grid, shift select the pink object, go in Front view, go in Edit mode and in the header menu, choose Mesh > Knife Project. In the Operator box, enable the Cut Through option. Do the same for the second grid (side view), here is what it gives:

You could as well use a sphere as a grid:

Give your pink object a Shrinkwrap modifier, increase slightly the Offset so that the sphere and the pink object don't cross each other:

You can give it a bit of thickness with the Solidify modifier.


Changing camera location for one frame changes it for everything

You need to add keyframes to set the location at different points in the animation - otherwise Blender is not aware of how you want the object to move and assumes you are just moving it to its new 'static' location.
You should set a keyframe at the start of the motion - this can be achieved by simply hitting I and selecting 'Location' (or whatever property you are keyframing) while in the 3D Viewport. Then move to the end frame and move the camera and, again, add a keyframe using the same process. Your camera should now move between those keyframes when you play the animation or move through the timeline.


It sounds like you managed to simulate the smoke, but you can't render it. The reason is probably one of two:

You're using Cycles in a old Blender Version
You're using Blender internal, but haven't yet setup a material.

If you're trying to use Cycles to render smoke, it is possible now. Volumetric shading (the shader that makes smoke) is initial supported since 2.71. (see Release Log)

Setting up a smoke material is kind of difficult, so read the docs if you want all the details (they also have some screenshots if you get lost).

Here's a quick rundown of how to create the material:

Make sure you're using Blender Internal.
Select Volume from the material type (right between wire and halo)
Set the density to zero (we'll be affecting the density with the texture)
Go to the texture tab and create a new texture.
Change the texture type to voxel data.
In the Voxel data panel, do two things:

Set the file format to smoke
Set the domain object with your domain object's name

Scroll down to the influence panel
Check Density, Emission and Emission Color and leave them all at 1.000.
Hit Render!


Material skews and stretches when placed on a new object

Object Texture Coordinates with uniform scale

If a procedural texture has no input, by default it is mapped with Generated Texture Coordinates type which basically have a Z coordinate value of zero at the bottom face and 1 at the top faces.

As your object is tall, between the two faces there is a lot of space to be filled compared with the other object where the texture looks un-stretched.

To get rid of the dipandency from the geometry size I would suggest to use Object Texture Coordinates, which is based on the Origin location and Scale. Using a uniform scale for the object (e.g. 1,1,1, 0.2,0.2,0.2...or applying the scale with Crlt+A) will result in a isotropic texture mapping too.


How to copy animation attributes to multiple objects?

Link the Animation Data of the active object to the other selected objects via Make Links menu:

Create an Empty (or every other type of object) and animate it (according to the scene)
Select all desired objects and finally the Empty to make it the active object
Press Ctrl+L and select Animation Data

Object visibility animation

Note: Since all those objects now share a single Action datablock you can update the animation on any one of the objects and the change will be shared by all the other objects.  If in the future you need to be able to edit the animation of one without affecting all the others, you can use the N-panel pop-out of the NLA editor, or use the Dope Sheet's Action Editor mode and click the Make Single User button (this will make a copy of the action so it is not shared with the others).


This is because the mouse actuator 'snaps' the mouse cursor to the centre of the screen when you use it. So when you initially click on an object, the 'snap to the centre of the screen' causes the view to jump.

The solution is to use a custom script to do this sort of mouse panning:

import bge
import mathutils

SENSITIVITY = 3.0
Y_INVERT = True
HIDE_MOUSE = False

def look(cont):
    if cont.sensors[0].positive:
        if HIDE_MOUSE:
            bge.render.showMouse(False)

        # Grab the location the mouse was clicked in:
        start_pos = cont.owner.get('PREV_POS', bge.logic.mouse.position)
        if HIDE_MOUSE:
            cont.owner['PREV_POS'] = start_pos

        # Calculate rotation difference to current position
        current_pos = bge.logic.mouse.position
        diff = mathutils.Vector(start_pos) - mathutils.Vector(current_pos)
        diff *= SENSITIVITY
        if Y_INVERT:
            diff.y *= -1
        # Rotate the objects
        cont.owner.applyRotation([0, diff[0], 0], True)
        cont.owner.children[0].applyRotation([0, diff[1], 0], True)
        current_rot = cont.owner.children[0].localOrientation.to_euler()
        current_rot.y = min(1.5, max(-1.5, current_rot.y))
        cont.owner.children[0].localOrientation = current_rot

        # Set the mouse position back to where it was
        if HIDE_MOUSE:
            bge.logic.mouse.position = start_pos
        else:
            cont.owner['PREV_POS'] = current_pos
    else:
        del cont.owner['PREV_POS']
        bge.render.showMouse(True)

However, this script requires a some setup of objects. It should be run from an empty parented to an empty parented to a camera.

It is much less time consuming for me to provide a blend file, so here you go:
https://drive.google.com/file/d/0B27awtGNGuMPZENxMWwtQkdSTEk/view?usp=sharing

Have a look at the set up, and try replicate it in your own system. Let me know if you have issues, and I can add more detail to this response.


Found it. The terrain object has a UV map. This causes the diffuse color to be overridden in multitexture view, as the texture under the UV map is displayed instead. Apparently a blank texture appears as white.

This won't affect the render, but if you want the texture display to be consistent, remove th UV map in Properties editor > Object Data > UV maps.


How do I stop curves from changing shape when joining them?

Okay, so I needed to turn the curves to mesh using alt c and then join them. At least I ended up figuring it out!


Blender Game Engine: RayCast to get a point

The hitPosition of a Ray sensor will give you the coordinate of were a ray hits an object.

To use it, add a Ray sensor to the object and connect it to a Python controller.

Create a text block and enter the following script to access the hitPosition.

import bge

controller = bge.logic.getCurrentController()
owner = controller.owner
ray = owner.sensors["Ray"]

#world coordinates of where ray hit object
ray.hitPosition

Finally, enter the script name in the Python controller.


I can't write english well. So my answer is picture.


Activate the Absolute Grid Alignment option

EDIT In your case it seems to not working because of the armature, Blender can't figure out how to snap the vertex the final transformation of the vertex to the grid because of the deformation introduced by the rig.


It turns out that the rings in the smoke were caused due to the fact that I had my 3 smoke domains positioned at exactly the same location and were the same size. I changed the size of each domain and their locations slightly which resulted in good smoke. I'm still not sure what caused the smoke to be hidden diagonally but that seemed to go away as well.


Is there a hotkey to subdivide geometry?

You're looking for subdivide. It doesn't have a shortcut by default, but you can assign a custom hotkey by rightclicking on the menu item under mesh-> edges -> subdivide

in my case it's set to alt + w


How to solidify (cylindify) a screw a with cylinder instead of a rectangle?

I figured out a pretty easy way to do this
First, create a circle mesh (not a sphere) and ↹ Tab into edit mode. Press A and F in that order to create a face.
While in edit mode, grab the face, hit G, X and press 2 in that order to move it to the right.
Stay in edit mode, press period key, and change it to 3d cursor.
Then, grab your circle, hit ⇧ Shift+D, R, Z, 60 in that order. Repeat this 5 times to get this:

After you get this add the screw modifier, and it should work


defining angle of reflection for glossy texture nodes to make "holographic" metal

It's up to you to play with the values and other options to get something you like, but here is one way to play with the normals of red, green, and blue glossy shaders:

Mapping nodes are used to adjust the "Rotation" values of the "Normal" output from the "Geometry" node.  I added some displacement to the cube to highlight the effect.  It's not all that close to your example, but maybe it's a good starting point for you to experiment.


Non-Uniform Scaling during UV unwrap. What is this?

It's because your object has been scaled on some axes more than others in object mode.

For example:

It should be fine, but if you are having problems you could try applying the scale by pressing CtrlA> Scale in object mode. This will apply the object mode scale "offsets" to the mesh data, resetting the offsets to 1 without  changing the appearance of the model. Note that this could affect modifiers such as bevel. See Why are the longer edges being beveled more?


Object with particle system doesn't appear but particles appear

In your Particle System, in the Render tab, check that the Show Emitter checkbox is on


Convert Grease Pencil textured strokes to SVG file in 2.8

is there at least a method to render the Grease Pencil on a transparent background?

There is an entry in the Context-Render panel named "Film". Open it and set a hook at "Transparent".


Make sure you've selected both Armatures in object mode, and then go to Object > Join


How can i give my 3d ring a design with waves and other lines?

Topics:

UV mapping: how to map an image onto a mesh.
Shader Nodes: how to use images in various ways in your material, not just color.

In short, you need to UV map (nothing to do with ultraviolet) the ring’s outside. You can probably get the desired result by (with the proverbial finger of the ring pointing straight up):

selecting the top and bottom borders of the ring,
then selecting a slice of edges to break that into a strip when it unwraps,
marking all those edges as seams,
and then selecting all the outside of the ring (everything that falls inside that strip),
and “UV unwrap”-ing.

If that UV mapped the way I think it will, then using an image such as the one shown above in the ring’s material should wrap around it.


How to melt an object then reverse the melt into another object

You could use fluid 'Control' objects to control the fluid in a fluid simulation. These allow you to set up a mesh that acts as a force that attracts the liquid. By controling the force (using keyframes) on multiple control objects (each set up for different text) you should be able to manipulate the fluid as desired.

For example, here's a set up with a fluid sim domain containing some fluid along with a control object in the shape of the word 'Text' set up as a Control object with suitable forces to attract the liquid :

It seems that care needs to be taken when using multiple fluid control objects - in particular, I appeared to get interference causing the fluid to be repelled from one control object when I tried to get it to be attracted to the other. It seems the solution is to ensure you always have at least some Radius to the control object's influence when it's in use. Also, it appears that you need to adjust the Strength down to zero before you disable it by keyframing its 'Enabled' property.

As mentioned in a comment, the body of fluid can be removed from the final render by way of a Boolean modifier and a mesh (eg, cuboid) to cut away the excess fluid. Also, keep the fluid domain as small as possible to avoid wasted processing - using high quality control objects really does slow down the bake.

Here's my final result :

This was achieved by keyframing between two control objects - one 'Text' and the other 'here', while varying the Radius (reducing from high to low to affect the influence away from the control mesh) and Strength (increasing to grab the fluid and reducing to zero to release it). The additional fluid reservoir was removed using the Boolean modifier to remove everything within a 'Mask' mesh.

Blend file included (you'll need to Bake the fluid domain which will take some time)


bpy.context.space_data.text throwing error from command line

In the text editor window the [filepath] refers to file location where you save the script.
In the console window there is no such structure.

import bpy
import datetime

print(datetime.datetime.today())
print(bpy.context.space_data.text.filepath)
print(bpy.data.filepath)

The above was executed in the Script window.  You can compare the results.


its definitely possible.

you've got to model your drawing.

how to model

When I start creating a character, I draw it on a paper how its supposed to look from the front, then how its supposed to look from the side.
Then you put your drawing as a background image in blender and model the mesh along the lines of your drawing.

give it an armature, that armature acts as the skeleton of your model and you can animate the bones of that armature.


How do I set up a material with diffuse, normal and alpha (transparency) maps?

The only problem I see in the node setup is that the normal map image texture should be put through a normal map node to convert the color output data of the image texture to the required normal input of the shader.


How can i get 'shining' borders to a material in Blender Render?

Finally i found a solution, at least, it's working, but isn't a configuration based on the material, but in the lighting on the scene itself.

Afte creating a regular basic Fresnel texture, with geometry bump added of a texture based on a photography of rocks (on this case) and added two Sun type lamps at the side of the scene based on the position on the camera.

The 'effect' didn't worked at first due to the specular activated, it was too shiny and it even looked like plastic, but after deactiviting it, it worked a lot better, and also i added a little translucency parameter of 0.028.

And the light strenght itself, based on the distance has a parameter of 7.

Also, as a tip, the effect worked since the camera only 'zooms' into the objects and rotates but following a direct (invisible) line between only two points. Still, i rotated every single DNA object with their respective individual parameters and the effect doesn't change at all, because the position of the lighting also doesn't change.


How can I make a curve higher resolution?

You can increase the 'Resolution' of the curve from the 'Data' tab while the curve is selected:

Bare in mind, the higher you set this, the more geometry that has to render, so renders may become slower.

You only need alter the 'Preview' resolution if you like, when the 'Render' resolution is 0 it will default to whatever value the 'Preview' is set at. Alternatively if the viewport was becoming too slow you could have a lower 'Preview' resolution and 'Render' set higher.

If you have given the curve a bevel you can increase the resolution of the bevel by increasing the 'Resolution' value in the 'Geometry' panel in the curve properties.


Go to File, User Preferences, then under Addons search for Planes and enable Import Images as planes, then simply do File, Import, and choose images as planes. Select the Image you want to import and viola, it will be imported perfectly scaled and UV mapped automatically.


Collision/Rigid body objects not moving an inch

Scale problem. Since I also used Blender for 3d printing (with scale unit configured at 0.01), all my 3d objects use this scale, and it seems to affect rigid body behavior. I was able to get around the issue switching back to 1 scale unit. It's still not working properly but it's sufficient as for now.


Can you clarify the contents of your scene? PLY is a very niche model format and has a lot of limitations when it comes to the data that it can package. You might want to read up on this page.
Try just exporting a simple scene and see it that works. If you can export PLY with just some simple geometry, then it must be something contained in your scene that isn't able to be exported.

Everything seems to be working fine for me with just some simple geometry in the scene. If it's still grayed out with just some simple models in your scene, then you might want to try re-enabling the PLY export add-on in user preferences.

How to re-enable the PLY exporter in blender:

Go to File --> User Preferences (Ctrl+Alt+U).
Click on the Add-ons tab at the top of the window.
In the search box, type "ply."
Make sure the checkbox is ticked next to "Import-Export: Stanford PLY format."
Click Save User Preferences towards the bottom right hand corner of the window.

If the problem still persists, then you'll probably want to ask your client if he or she can accept another file format. PLY is a pretty non-standard format and I can't imagine what situation they would be in to only be able to use that format.
The last thing that I want to add is that you must have objects selected inside of your scene to export them. To export everything in the scene, just his A and then export.


How fracture an object into spinters like it's made of wood?

The cell fracture addon allows tweaking of the "aspect ratio" of the shards via three scale values:

Note that these seem to adjust the scale of the shards in a similar fashion to the way the mapping node works (adjusting the scale of the texture by adjusting the scale of the coordinates). These means that it works backwards from how you might think, smaller values make the shards larger in those directions (0 is infinity). So setting the Z value to 0 will make the shards infinitely tall (bounded by the original object of course).

Setting the Z value to a very low number works okay for getting a splintery fracture:


Armature deformation behaviour with shape keys

I got this working by using the "Corrective Shape Key" addon. So I posed the armature in the end position I wanted. Then I selected the mesh object (bulb) and hit the "create duplicate for editing" in the Shape Keys group of the objects data tab.
Selecting both (copied first and then original) objects and hitting "Join as Shapes" from the same menu creates a new shape key with the copied objects shape as final mesh deformation of this shape key.

I then did this with all four directions the bulb is able to bend.
This work nicely with one nasty exception. The motion is not exactly a copy of the armatures motion, the top of the bulb changes length during bending, which in the armature is forbidden. The bulb is actually attached with top and bottom lips to metal parts. So now when I make the angle sweep, a gap between the bulbs lips and the upper metal part opens and closes again. I hope to get around this issue soon...


Let's see if I understand: you have a cube that is not aligned to the XYZ axes:

If you want to rotate it along its Local Z axis, then you only have to do R, then Z twice ("Rot: along local Z" appears in the status bar):

However if you want to animate the rotation of the object through keyframes, you first need to set its Rotation mode to "Quaternion":

That's the result with the default Rotation Mode ("Euler") and "Quaternion":


FIX(connect/merge) loose vertices after an edge split modifier

go into edit mode
select everything by pressing A
press W
select remove doubles

Also, don't use the edge split modifier. If you want to smooth your mesh, i suggest using "auto smooth".


There are several standard blend files provided by the Blender Foundtation for testing and benchmark purposes available at Demo Files. The BMW scene as become a common test scene for various purposes.

In recent years due to the popularity and it has become an informal benchmark tool used by hardware manufacturers to provide a common ground for comparison. This has the advantage of using real world computational needs rather than artificial benchmark tools created for the sole purpose of testing

As such the Blender foundation has started a new initiative to provide an official reliable benchmarking tool for testing purposes.

This has materialized as a website called Blender Open Data that aims to collect performance data for various hardware configurations.

As of November 2018 status is still in beta testing, so not much information is available at the moment.


Create window - problem with geometry - bevel and vertices?

The reason for this is simple—you're using a mesh. Meshes can't use curved lines; all Blender can do is approximate them with a bunch of straight segments.

If you really need it to be truly curved, you can try using Curves instead. Unfortunately, I don't think it's possible to use a curve with the Boolean modifier, however, so getting it to cut out a window would be quite difficult. I'd use a CAD editor (here's a list) if you need that.

If you don't need that, but want to change the number of segments, look in the bottom left corner of the 3D view. There's an options panel where you can tweak whatever action you did last (but if you did something since then, you'll have to undo and re-bevel it). To add more segments, you can also use the Subsurf tool – select the vertices, and hit W and then "Subdivide Smooth".


Where is the sampling menu in Blender version 2.77?

You are currently in Blender Render. Change to Cycles at the top of the screen.

to

Alternately, if you want to reduce noise in a Blender Internal render, select the light, go to the Properties panel > Object Data tab > Shadow dropdown and increase the light's samples.


can the system console window default position be adjusted?

thanks for pointing me in the right direction!

I've solved it using a slightly different approach (using pywin32), but here it is:

import win32gui

def _windowEnumerationHandler(hwnd, resultList):
    '''Pass to win32gui.EnumWindows() to generate list of window handle,
    window text, window class tuples.'''
    resultList.append((hwnd,
                       win32gui.GetWindowText(hwnd),
                       win32gui.GetClassName(hwnd)))

windows = []
win32gui.EnumWindows(_windowEnumerationHandler, windows)

for w in windows:
    if w[1] == 'blender':
        win32gui.MoveWindow(w[0], 2650, 3, 1200, 600, True)

def register():
    return

this is specific to my setup of course, but should be easy enough to tweak for others


Why am I unable to extrude/translate along the Z-Axis?

This is because the Z scale of the object is 0.

Apply the scale (CtrlA> Scale) or set the Z scale in 3D view > Properties region (N) > Transforms > Scale:

Then extrude/translate should work fine.


Shrinkwrap remnants - during model wall creation

The Shrinkrap Modifier is not really a fire and forget kind of tool that takes care of everything. It needs some love.

Here is how I use it:

I model a very low poly mesh that wraps around the target. In this case a simple circle with 6 verts. It's not just a blanket thrown over everything. Any topology worth considering is mirrored lowpoly in this mesh. The structure of this mesh is crucial. It makes sure my result has a nice flowing topology instead of being a random mess. Blender's workflow and chaotic topology don't harmonize all that well.
Step two is a Subsurf, can be a simple one, so the Wrap has something to work with.
Step three is the actual Shrinkwrap Modifier that gets its offet.
Step four is adjusting the verts. In some places the modifier will goof up. It needs guidance. But since all the geometry is procedural, you can still adjust the lowpoly base to help the Shrinkwrap along. It'll search for the closest surface point and its the modeler's job to make sure the right spots are closest.

If you want to, you can sandwich the Shrinkwrap between two subsurfs where the first is for shrinking and the second is for smoothing.


How can I move an object on a plane of two axis like XY?

By pressing SHIFT+X, SHIFT+Y or SHIFT+Z, while you're grabbing (G), the operator will constrain the movement in that axis. So G then SHIFT+Z will just move the selection in the XY plane.


PNG takes longer to read or write, because the computer needs to compress it. Therefore it takes up less space. TGA is largely uncompressed, so it's being written and read faster, but takes up more space. Both formats are loss-less, but I think the color range of TGA is larger.
Targa is popular in Game Enginges because the Alpha channel is independent from the color channels and it reads very fast. EXR is usually the largest, but it supports HDR. I haven't tested it, but it should be read faster than PNG.


So I'll just post this as an answer but if anybody has a better suggestion feel free to share!
So I managed to get it to work thanks to moonboots's comment

As suggested I made an armature and just scaled down each branch seperatley and then rotated it so it's hidden inside the mesh. It looks fine from a distance but not so great up close


Live rendering problem in all viewport modes other than Rendered

It looks like your clipping distance is not set optimally for this scene.

Generally when I see this issue, the Clip Start is set too low, and the Clip End is set too high. Try increasing the Clip Start to around .1m and the clip end to 500m

Note: These numbers assume that the Blender file is using real life measurements, or reasonably close to it.


Start with a landscape (this one was created with the A.N.T. landscape generator).

(Click on the images to enlarge)

In a different layer I added a plane and used an array modifier to stack up vertical iterations of the plane. This will be used to cut slices across the landscape.

Then a Boolean modifier in intersect mode, with the landscape as target object :

Now hide the layer with the original landscape and add a solidify modifier. Make the thickness the same as the offset for the array modifier:

Editability:

Since this is done with modifiers, the landscape remains fully editable and the contour slices will accommodate to the modified landscape.

Thickness is fully customizable with the solidify modifier, and the array modifier can be set to have more or less detail in the z axis.

For a smoother result, the original landscape could use a subsurf modifier:

obviously the more detail, the more computing power will be needed for this project.


How can I increase the grid floor line thickness for major (or minor) divisions?

You can change the grid thickness in the Viewport Overlay drop-down menu.


where can I download cycles as an addon and why does blender not run?

Cycles cannot be downloaded as an add-on and installed in an older version of Blender - it's too tightly integrated for that.

In case of future googlers coming across this question, Cycles can be used standalone, but that's not really related to your problem.

If you believe blender should be able to run on your computer (your specific graphics card supports OpenGL 2.1, google the model name), then you should report a bug and let the developers help you find out what's wrong. When describing your problem, be very specific about what's wrong, what error messages there are, your hardware, etc.


I believe it's an issue with the density.

What you might want to do is start over and equal out the densities of Yellow and Red (several ways to approach this) before punching the holes to get an easier and cleaner result.

Alternatively you could add another ring and then retopo accordingly to get a cleaner hole.

Here's a quick example (sorry for the messy image).

I used bevel on the outer ring to add another ring.

Next time, please link the mesh so it's easier for us to help you :D


After a bit of digging when I ran into this issue again, I found out that for whatever reason, the vertex group for that particular bone didn't transfer to the mirrored mesh. As a result, the weights for the mirrored object were there, but the wrong bone was controlling it. In my case, I mirrored to the right side, and that part of the mesh was being controlled by the left side. Here's the solution I found:

Figure out what the missing vertex group(s) are in the vertex group panel. Watch for the one(s) that doesn't have a counterpart for the other side (For example: if there's a hair1.L and no hair.R, you've found one). Select the one for the side that you do have.
Use the grey arrow below the plus and minus buttons to copy the vertex group within the object and lock the original version.
Rename the copy to the bone you want to control it with (For example: hair.L_copy would be renamed to hair.R).
While the bones have control over their intended weights, they will still control the wrong side. Go ahead and fix this in weight paint mode by subtracting from anything that they don't need. Don't forget to unlock any vertex groups that you locked before.


How to model slice shaped circular wedge?

You could use your geometrical pattern as background blueprint, then:

Create a circle, extrude inwards (as suggested by the other answers, the Spin or Screw tools might be more convenient ways to create the initial shape):

Only keep a segment and delete its inner faces:

Extrude upwards, don't forget to recalculate the normals:

Give it thickness with the Solidify modifier (enable the Even Thickness option), or altE to Extrude along Normals and enable the Offset Even option in the Operator box:


How create realistic semi gloss paint shader?

Final:

Overview:

Material itself is pretty simple even without using complicated PBR (but you can try it of course - look for CynicatPro) but the devil lays in details which are Bumps in this case.

You should work on them, as they are different for different parts of the Tank. Also Roughness map would be a good idea. Some parts are shinier then others.

This setup is just Diffuse mixed with Glossy by Fresnel and with procedural Bump Map.

You can try to use texture for bumps, same goes with roughness map.


How can I convert a low resolution image to a mesh?

Maybe you should model the whole scene (make some quick low-poly models) and then use the Remesh Modifier. Set its mode to Blocks. Apply the modifier and then paint the model.


Cycles: Rendered Image's lighting doesn't illuminate as much as render view's lighting

You have hidden an object in the viewport, but not in the render. First enable the restriction toggle Disable in Renders (camera icon). Then disable rendering for object Curve.011 in the jack o lantern pattern 1.svg collection.


Can't bend svg image to a curve using simple deform

Probably the object don´t have the proper geometry. Meaning it doesn't have enough faces. It needs to have square faces or triangles to bend properly. Normally some are comprised of just one big face.


With the Displacement node plugged into the Material Output you're trying to give real displacement to your object. It won't work if you don't give it enough topology, you need to subdivide it.

Also, the Image Texture is supposed to be plugged into the Displacement Height input.

I'm not sure I would use this kind of effect for a hardsurface object though, it works fine for organic object but here it will require a very high-poly mesh, you should try to fake 3D with a Bump node.

Here I've subdivided the mesh to get the Displacement effect:

Here it's a low-poly with 3D faked with a Bump node (plugged into the Normal input of the Diffuse this time):


Appending rig with constraints and drivers

I'm relative new to Blender rigging. I have successfully appended 2.81 generation custom character rig with many constraints and drivers into 2.93.
I made sure to rename/ make the rig as a collection in 2.8 Blender (which I haven't uninstalled). Like, Mary Rig Collection.
Then I append the (clearly named and easily identified) COLLECTION into 2.93.
Usually there's no drama, just need to disable/ hide custom bones. Drivers will work, constraints are all there.
After double-checking everything, I re-save a new 2.93 Rig Collection blend file of this character.
Good luck.


export the length of edges to a text file from blender.

You can use this script, tested on happy.ply for performance test (6 seconds on my laptop):

import bpy
import time

#Calc the length between 2 vertices given by vertex index
def CalcLength( obj, vertices ):
    v1 = obj.data.vertices[vertices[0]] #Get the first
    v2 = obj.data.vertices[vertices[1]] #Get the second
    return (v1.co - v2.co).length #Calculate the length from their coordinates

#In object mode
obj = bpy.context.object #selected object
#obj = bpy.data.objects['name'] #or by name

fileName = "c:\\tmp\\exemple.txt" #Your file name

file = open( fileName, 'w+' ) #Open a file (will create or erase an existing one

startTime = time.time()

try:
    #Write to the file the length of each edge
    file.write( '\n'.join([str(CalcLength(obj, e.vertices)) for e in obj.data.edges] ) )
finally:
    file.close()

executionTime = time.time() - startTime
print( executionTime )

Here is the file so you can look at the setting:


The simplest solution would be to create an animation that can be looped.

The most "proper" way to do this is with the Action Editor and Dope Sheet, but I don't understand it well. Someone else might provide that info.

However, you can also use the Graph Editor. If you create an empty that you can animate and slave the turret to that (parent, track to, child of, copy location, vertex parent, lots of options there), you can animate one "vibration" of the turret and then just repeat that same action a number of times. To do that, select the channel that you want to repeat (you might have to do this with each channel), press n, click Add Modifier and choose Cycles. To make it vibrate on demand, instead of constantly, animate the Influence value. Turn Influence to 0.0 when you want it to stop, and then bring it back up to 1.0 when you want a burst of fire.

Note: You don't necessarily have to use an empty, you could just animate the turret, but using an empty lets you isolate the curves for that one animation from other animations you might want to do. I.e. you only add modifiers to the empty's curves, without affecting other animations that you do to the acutal turrets.

Hope that helps!


How can I morph a flat plane to be a flat cirlce?

The easiest way, in my opinion, is to use the 'Cast' modifier. Using a subdivided plane you can cast/warp an object from one shape, to another, preset shape:

Animating the 'Factor' allows you to switch between the original shape and the 'cast' shape.


No, it is perfectly fine to use both triangles and squares in an object. For example, the object below has squares and triangles, and it works just fine.

As discussed in the comments below, there are many reasons why you might prefer to work with squares when modeling instead of triangles, but you can definitely use both if you wish.


How to change a certain parameter of all principled shaders in my blend file?

You would have to iterate through all materials, get their node trees and find the principled bsdf to set its default values. Demo on how to change the Metallic value for all materials in the file:
import bpy

for mat in bpy.data.materials:
    if hasattr(mat.node_tree, "nodes"):
        for node in mat.node_tree.nodes:
            if node.type == 'BSDF_PRINCIPLED':
                for input in node.inputs:
                    if input.name == 'Metallic':
                        input.default_value = 0.7

If you'd like to change another property of the principled shader, here is a complete list:
Alpha, Anisotropic, Anisotropic Rotation, Base Color, Clearcoat Clearcoat, Normal, Clearcoat Roughness, Emission, Emission Strength, IOR, Metallic, Normal, Roughness, Sheen Sheen Tint Specular, Specular Tint, Subsurface, Subsurface Color, Subsurface Radius, Tangent, Transmission, Transmission, Roughness.
Note that some of them are actually vectors (yellow and purple socket) so you'd have to assign a tuple instead. Demo on how to set the Base Color:
import bpy

for mat in bpy.data.materials:
    if hasattr(mat.node_tree, "nodes"):
        for node in mat.node_tree.nodes:
            if node.type == 'BSDF_PRINCIPLED':
                for input in node.inputs:
                    if input.name == 'Base Color':
                        input.default_value = (1.0, 0.0, 0.0, 1.0)

Further reading: What is the meaning of the color of the node sockets in the node editor?


How do you convert text into a wire frame look?

Convert options are available through the Menu bar:

Object > Convert to > Mesh from text


Dilate/Erode: Difference between Step and Distance mode?

In Step and Distance mode, the Erode/Dilate node samples through all pixels and compares their value to the neighbouring pixels. If a neighbouring pixel has a lesser value, than it is matched the sample pixels value.

The following pseudo python shall demonstrate.

FOREACH a OF allPixels:
    FOREACH b NEXT TO a:
        IF (a > b):
            b = a

In Step mode, the adjacent pixels are right, top, left, bottom.

In Distance mode, the adjacent pixels include diagonal connections.

Here is a comparison of an example.


I am rendering in lower resolution, but background is not scaling down to match when rendered

No, blender will not automatically resize the image when you render at 50%. It will only render 50% percent of the pixels around the center of the image (Think of the percentage not as a resize, but as a crop).
If you want to resize use a scale node, set it to render size and Fit, so that the image is rescaled using the output resolution.


How to make object appear only inside a defined region

You can use Object coordinates of another mesh (set to not render) - or even an empty - to control the visibility of the text. This way when the text moves in relation to the other mesh it's visibility can be adjusted based on those translated coordinates. You can easily move and reorientate the other mesh in order to adjust the effect as desired.

Here's the material :

Note the Texture Coordinate node Object set to 'Cube'. This results in each coordinate being presented in relation to the other mesh rather than the text itself.

Adjust the Divide and Power nodes to adjust the drop-off and range of the fade-out.

This produces the following results :


Where is the common-sense button that aligns curve handles and resets them?

Edit Mode:

A Select all
V V Convert control points to Vector

With just 2 points, this will produce the straight line I think you're looking for? I do this to every Bezier curve on creation..  it just helps get off to a known, 'neutral' start.

After that, you might want to W S subdivide, (or, in 2.8 right click > Subdivide) to make more in-line vertices.


How do I make a glass texture with an outline?

To illustrate the suggested solution using Fresnel.

Combine a Glass shader (for glass) and an Emission shader (for the outline)
Add Fresnel input to drive the visibility. Change IOR to control the line thickness.
Use Colorramp  set to Constant for sharp outline edge


Change modifier key from Alt to Super/windows key

There is! This is for Blender v2.8-rc1.

Open Edit -> Preferences... from the menu bar, select Keymap from the left sidebar, and then Export... in the top right to export your current keymap. In the dialogue that opens, check the Export Key Configuration -> All Keymaps box.

Save the keymap somewhere. In the keymap file, replace every instance of "alt" (including the quotes) with "oskey". Go back to the Keymap pane in the Blender preferences and import your changed keymap. Whenever this keymap is selected, all the shortcuts in your previous keymap that used Alt will now use Super.

Of course, if you're already using OSkey for some shortcuts, this solution may cause collisions. The default keymap for Blender under Linux doesn't use it at all, though, and I assume based on your question that you haven't modified it to.

As a side note, there isn't actually a way to tell Blender to use Super in place of Alt  globally below the keymap level, as far as I can tell, short of patching it to do so. Blender only understands four modifier keys, Shift , Ctrl, Alt , and OSkey. OSkey represents a different key depending on the OS: Super under Linux, ⊞ Win under Windows, and ⌘ Command under macOS.

Shortcuts consist of a single key other than those four plus some combination of them. All keycodes are hardcoded with no way to change them in Blender's configuration; the raw keycodes seem to be in source/blender/windowmanager/wm_event_types.h but I'm not sure how they correspond to keycodes outside of Blender.

However, you might be able to patch source/blender/makesrna/intern/rna_wm.c, changing the item(s) for the key(s) you want to use in place of Alt in rna_enum_event_type_items[] (OSKEY, in this case) to use the values in the items for LEFTALTKEY or RIGHTALTKEY. I haven't actually tried this, so I'm not positive it would work; it would be a hacky solution if it did, but I'm not sure there's a better way without making big changes to Blender.


What does the F in front of brush names mean?

It stands for Fake User. Since the default brushes all have fake users, the "F" shows up in front of the name.

Note: This applies to many other data-blocks, not just brushes, its just noticeable since fake-user is enabled by default, but it can be used used for meshes, curves, actions, fonts... too.


How to make a cell shaded scene using the compositor

You can create both cell shadows and highlights using the "Normal" render pass. This is how such pass looks like, when enabled you can view it inside UV/Image Editor selecting the Normal pass:

Render the scene without shading (or with minimal shading - ambient occlusion, etc.) and add cell effects in compositor like this:

Quick intro into compositor can be found here. Add nodes through the menu or with Shift+A.

You change the direction of shadow and highligh with those Normal nodes.

For nice edges Full Sample Anti-Aliasing should be on (Blender Internal setting):

Result:

It is worth noting that the Normal render pass is in global space (= coordinates relative to the world) and not camera space (= coordinates relative to the camera), so camera movement will not change the shading (it will not change how the normal pass looks like).

If you need cell shading working like a MatCap material is working, you will need a custom normal pass transformed into camera space. Since compositor has no Vector Transform node it cannot do this.

The solution is to create another render layer and override all materials in it with this material:

Use this layer instead of the Normal pass to make the shadow and highlight relative to camera and to follow it's movement.


Straighten the series of vertices in UV editor

If you don't want to straighten your UV islands (How do I straighten UV maps?), cause in your case it might be very time consuming you might repeat the steps I've shown in the .gif below.
In Edit Mode select all faces (A), press U-->Lightmap Pack-->OK. Now select one of the face to make it active, then again press U-->Follow Active Quads-->OK. Your UV island is straight now. Adjust it using G, R and S to fit the image. If your mapped image is upside down just scale it negative 1 (S,Y,-1).


Why does the measurement tool not snap to vertices?

Hold Ctrl to enable snapping.
The Measure tool only snaps to vertices and edges.
Notice the bottom status bar gives you all available commands


How to automate polygon reduction using python?

I'd recommend using instant-meshes with it's batch mode. You could write a python script like this one to do all the files in your folder:

import subprocess
import os

models_folder = 'C:/folder'
models = sorted(os.listdir(models_folder))

output_folder = 'C:/output_folder'

instant_meshes_path = 'C:/Instant_Meshes.exe'

for file in models:
    # Desired number of faces for the model
    faces = 2500

    subprocess.call([
        instant_meshes_path,
        '--faces', str(faces),
        os.path.join(models_folder, file),
        os.path.join(output_folder, file)
    ])


Ok, it's in the Geometry > Bevel Settings > Use Spline in the Bevel > Bevel mapping > Start & End.


What is the workflow for compositing Fire/Smoke with Cycles

Expanding on tobkum's answer, an example workflow using the technique in this tutorial might be:

Setup BI scene (simulation, etc.)
Create a new scene for Cycles, with Link object data
Create Cycles materials, linking to Object instead of Data so BI and cycles materials are not synced:

In the BI scene:

Create BI materials, again using Object instead of Data.
Disable shadows for all BI materials except the smoke
Create renderlayers for smoke and smoke shadows using the Shadow pass.
Create renderlayers for reflections and refractions, and remove sky by setting the Horizon color to black.

Setup compositing in Cycles scene:

Create renderlayers for foreground and background objects
Multiply BI shadows with cycles background layer
Alpha over BI smoke over cycles background layer
Alpha over cycles foreground layer over composite
Add or Mix BI reflections and refractions to composite

Render


Start Blender in Debug-Mode as stated here:

In 2.8, Blender crashes while rendering trees

that creates a log file which you can inspect


your domain has no material.
Add this material to your domain, and you get this result in render:


There is an "import GIMP" addon currently available, but it doesn't look like it's very stable at this point. You can activate it under User Preferences > Addons > Import GIMP to scene. Use key search word GIMP to locate it. Then it just a matter of opening the import menu, selecting xcf and importing the file. like I said though, it's kinda unstable, wait for more hardy versions to come out if you can.


Two simple ways to achieve this:

Either Create a regular mesh cone, subdivide lateral edges with W+ > Subdivide, then and scale them horizontally using Proportional Edit with S, Shift+Z, or
Draw a bezier curve object outlining your cone silhouette, then add a Screw modifier to it. This method can also wor if you draw said silhouette with a string of mesh edges.


World background a finite distance from the origin?

Overview:

You can use your HDRi map as a Emission color on the Sphere (big one, mine is above 100m in diameter). Set Image Texture projection to Sphere as well.

Differences:

Using this method you will get more noise as for any mesh light in Blender. Everything else like reflection, shadows etc. should be the same.

Environment map (HDRi):

HDRi mapped to the Sphere:


How to Check How Many Frames You Have Left to Render

It looks like it is on frame 11, subtract that from the total number of frames (Check your timeline, Blender usually starts with 250 frames in the timeline), If you don't need that many frames, lower that number and it should finish quicker.


Trouble with __init__.py loading addon with multple files

Answered by @batFINGER in comment:
Just had to zip the folder with files in!
Trying to make a menu using multiple modules


How to copy multiple values between objects

Make sure the Copy Attributes Menu addon is enabled (by default embedded with Blender but not enabled). Then select first the object(s) that should receive the properties, then the target object holding the Shift key > Ctrl-C > Copy Location/Rotation...


How do I get out of this weird zoom in/out?

Welcome to Blender Stack Exchange!
At the lower right corner of the 3D view, under the View heading, there is a setting called Lens that is currently set to 1. That is the focal length of the viewport camera, and should be set to something like 50 (the default in the current release of Blender).
Changing that value should solve the issue.


How stop moving the view when entering walk mode?

I just fixed the issue with the help of dann#6226 (Discord)

try to change the shortcut, I suspect it might be doing two things at once.

does it do this if you use the menu to enter and exit?

I was using middle mouse, and multiple actions where having the bind on this button. Changing it to another key and making sure to not be used by other actions too, fixed the problem


How to change dimensions of an object proportionally?

There is a solution since version 2.70:
http://wiki.blender.org/index.php/Dev:Ref/Release_Notes/2.70/UI#Multi-Number_Button_Editing

Click and drag from the first to the last fields you want to edit and release the click. The three fields are highlighted. Enter an expression, eg. *3/2 and press enter. All fields are edited at the same time.


you can save it at a logical place for you, you don't have to unzip it. In blender you open the user preferences --> add-ons--> install from file, locate the file and than check the file.


There were objects on meshes added after the transparent object was added. These objects failed to appear through the transparent object.
The transparent object was on its own mesh.
Objects, added before the transparent object was added, appeared through it.

Moving the later added objects higher, in the Scene outliner, remedied the problem.
Objects were moved by creating new meshes and making them the parent of the objects added after the transparent object.
There's probably a better way to do this, but I'm just grateful to have found a solution.


Orient an object relative to another and constrain distance to radius

Objective - Make a cone follow (track) a cylinder's location whilst maintaining a constant distance from it. (as distinct from straight out parenting)

A script would be the elegant way to do this but for a quick handcrank job, read on...

The cylinder is the parent of an invisible (green) plane.  The plane's pivot point has been set to one of it's ends so it will always pivot out from the cylinder's center.  It's far end will be a constant distance from the cylinder's center.

The plane is parented to a vertex placed at the cylinder's center.

This prevents the plane from rotating topsy turvy as the cylinder does but will follow changes in it's location.

The cone is parented to the plane and positioned at it's far end.  It is also rotated to be looking back along the plane's axis and always pointing at the cylinder's center.

An empty has been placed somewhere central to and above the cylinder's anticipated motion. (along a path in this instance)

The plane is then given a constraint to "Track to" (look at) the Empty.

The empty can be moved about to vary the cone's orientation.


Why will audio and video not sync in rendered video file?

I loaded up your syncTest01002Rev.avi file and playback wasn't in sync. Inspecting the file with ffmpeg gets the following message: "[mpeg4 @ 0x19ecc00] Invalid and inefficient vfw-avi packed B frames detected". Re-encoded to fix the error, when loading into blender, it had an extra frame (680) and worked without issue.


Separate in two parts a Mesh using Knife Project

After further research, I have decided to scrap everything that I had before (it isn't that complicated). You can see my edits if you'd like to see the "old" way.
1. Select all vertices
This is pretty self-explanatory. Make sure you're in edit mode, then hit A
2. Use the Bisect tool
Just drag and you should get a live display of where it will cut. (You can alternatively use the plane and knife project at this stage if you'd prefer. Just make sure to enable "cut through.") When you are done with Bisect or Knife Project, you should have the "cut" selected.
3. Rip/Tear the selected ("cut") vertices
For this step, hit V, then left-click before moving the mouse. This essentially makes a nice set of double vertices on the edge of the cut.
4. Select the top or bottom
Deselect all, then you can use the L select linked tool on the top or bottom. Make sure you get everything in the top including the half of the cut line.
5. Separate the mesh
Use P + Selection to quickly separate.

Here is the complete GIF (I finished the operation in 30 seconds):


How to smooth a cone side without changing its shape?

The easiest way is to actually use a cylinder. you can then shrink the top to a very small size in order to make it feel like a cone. Then add an edge split modifier and the SubSurf.
The reason a cylinder is better is that the edge split doesn't work really well for triangles, and the cone basemesh is made of triangles. (You can't add edge loops on a cone).

On the screenshot I made the cylinder top big so you can see it's actually a cylinder but feel free to shrink the size as you want.


How can I uncomment "#" a line using python?

Yes it is possible, but not very useful. The following naive code attempts to change line 4 of its text block within Blender. The function modify takes 4 arguments.

name - the file name of the script
lineno - the line number to change (zero based)
orig - the original start of the string to change
repl - the replacement

So if you execute the script twice, the code will be commented again. The script will attempt to find its own file name in the last 2 lines. Only tested for Linux.

import bpy
import ntpath
#this is a comment
#print("Hello Blender!") # this is code

def modify(name, lineno, orig, repl):
    t = bpy.data.texts[name]
    s = t.as_string()
    l = s.splitlines()

    if l[lineno].startswith(orig):
        l[lineno] = l[lineno].replace(orig, repl, 1)
    elif l[lineno].startswith(repl):
        l[lineno] = l[lineno].replace(repl, orig, 1)

    t.from_string("\n".join(l))

head, tail = ntpath.split(__file__)
modify(tail or ntpath.basename(head),3,"#print","print")


Why won't logo display properly in solid mode?

The most likely cause is Self Intersecting segments. The same happens if you have a text object and extrude it to the point where Curves intersect other curves:

From: text-objects-are-messed-up-when-using-offset/2727#2727  (Different question, same answer and reason)


How to make object transparent on "texture" view mode

You can do it in Material viewport shading, which isn't all that different from Texture.

Set the shading to Material and add a material with the following node setup to your object.

On the Properties Editor make the following changes.

Now change the color of the RGB node to your liking.

If it's imperative that you use Texture shading, the following method should suit your needs just fine (it also works in Material shading):


Eevee
Just an illustration of Coby Randal's comment - Shader to RGB node.

In case you want to keep AO ...

Note: I wanted to composite AO pass (instead mix it in shader), but with this shader is AO pass wrong for some reason.


How to generate a full sprite sheet automatically

Perhaps putting a Cycles modifier on the animation fcurves so that the animation repeats for each of the different camera angles ( for 23 * 8 frames) would accomplish your mission:

The biggest stumbling block is making sure you have the right span of keyframes to control how many frames the cycle has.  You will probably find yourself adding keyframes at the beginning and ending of the loop (frame 30 and 53=52+1) to ensure that it loops correctly.


Baking is not supported on OptiX GPU rendering. Just switch back to Cuda, Go to Edit, Preferences, System > and wall la, Thank you.


As Robin Betts says, Apply Scale does work for curves as well.

If the Normals length are bothering you, you can change the display in the N panel (3D properties) > Curve Display > Normal Size


That can be done very quickly with Loop Tools addon that can be found and enabled in the user preferences.

In edit mode select top and bottom loops and in tools panel look for Loop Tools section, select Curve and all the intermediary loops will be aligned automatically.


You can use Object.to_mesh() to create a mesh datablock, which has deformations and modifiers applied. Mesh.transform() that with .matrix_world for world space:

import bpy

C = bpy.context
ob = C.object

print(ob.data.vertices[0].co, "- Vert 0 (original)")

me = ob.to_mesh(scene=C.scene, apply_modifiers=True, settings='PREVIEW')
print(me.vertices[0].co, " - Vert 0 (deformed/modified)")

me.transform(ob.matrix_world)
print(me.vertices[0].co, " - Vert 0 (deformed/modified, world space)")

bpy.data.meshes.remove(me)

Note that vertex indices may differ after modifiers are applied (e.g. Array, Bevel, ...).

Alternatively, the bmesh module can be used to achieve the same as the above script.


How to make mesh axis in local mode like in custom mode?

How have you rotated the cube?

Local transform orientations do follow the object's transforms.

But If you've rotated the cube in edit mode instead of object mode, then you have rotated only the mesh inside the object. Not the object itself, which rotations haven't changed.


A "texture set" is the full set of textures for a material, as you've listed above.  For example, diffuse, specular, roughness, metalness, etc. = 1 texture set.  If you download a PBR material from a site like CC0 Textures, what you get is 1 texture "set."

I'm interpreting this requirement to mean that they want separate materials with separate texture sets.  In other words, don't put the leather and wood on the same maps.  You could of course put the all of them into one texture set, with just different parts of a map defining different material parameters but it sounds like they want it separated by material.

So the "leather" material would have its own diffuse, spec, etc., and the "wood" material has its own textures as well.  Sounds like this was your plan anyway.

Secondly, you are correct that Specular and Metalness are usually two different workflows.  I think your client wants the flexibility to be able to use either one.  Maybe they aren't sure which renderer they will use in the end.


'Child of' Constraint, setting Inverse doesn't work?

The problem is double parent transformations:

first from parent
second from child_of_constraint

The solution and how to cleanly set this up is:

do not give the Mag any parent, all parenting will be done with constraints
position the Mag so it is both in the gun and in the hand
set 1st child_of_constraint to the gun and Set inverse
set 2nd child_of_constraint to the thumb and Set inverse
switch parenting with key-framing both constraint influences, gun_parent will go from 1 to 0 and hand_parent vice-versa.


A better way to do lighting in Cycles is to use emission planes. First, add a plane with Shift + A > Mesh > Plane. Then, rotate the plane to face a significant point in your scene or at your object:

Next, add an emission material to the plane by going under the Material tab and clicking New. Set the material's Surface to Emission and give it a Strength of at least 15 or so.

You can use as many of these planes as you want, but try to add only as many lights as you would need in the real world.


Lock X and Y axis of vertices in edit mode from python

Once you start moving an object you can press Z to lock all motion to the z axis (preventing changes in x or y).

https://docs.blender.org/manual/en/dev/editors/3dview/object/editing/transform/control/precision/axis_locking.html


Why does this procedural material distort at larger scale?

The culprit is this musgrave texture :

I set the dimension to 0.4 and the patterns disappeared. Try never going so low with the dimension parameter because it causes repeating patterns.


The mesh has custom normals.
Uncheck "autosmooth" in the property panel (object data tab, normals section).


I think the problem was i was using a very simple model , a cubelike model , which didnot have any normals but the 90 deg so i tried to export the monkey model and it worked


The history file is managed by C code, see e.g. wm_files.c.

You could exchange the recent-files.txt by script maybe, then let Blender reload it by calling bpy.ops.wm.read_history() as seen in wm.py (everything else requires changes to the C code).

Example script that switches recent-files.txt and an also required recent-files-2.txt (you need to create this manually) and triggers a refresh of the Recent files list:

import bpy
import os

fp = bpy.utils.user_resource('CONFIG')
src = os.path.join(fp, "recent-files.txt")
tmp = os.path.join(fp, "recent-files-1.txt")
dst = os.path.join(fp, "recent-files-2.txt")

if os.path.exists(src) and os.path.exists(dst):
    os.rename(src, tmp)
    os.rename(dst, src)
    os.rename(tmp, dst)

    bpy.ops.wm.read_history()

You could also append to recent-files.txt, or re-write it completely. Just keep in mind that Blender ignores files that do not exist, and will remove them from the text file.


How can I change the camera to include more of my scene?

This is the Default 35mm frame

There are two ways you can bring more content into frame.

Lower the focal length of the camera, in this case from 35mm to 25mm

Back the camera up (I prefer fly mode over grabbing because I can see the result while doing so)

Go into fly mode, shift + f,
do not move the mouse while doing this (otherwise you will change what you are looking at)
back up, s

Note that cameras with a low focal length can look weird, look at this 10mm example


Tracked background does not show in final render.

Thank you! I found the nodes I needed to change just under one button: screen layout 'compositing' > Node tree display and edit 'compositing nodes'. The wrong display was set so I couldn't see the nodes for background.


What is the most effective way to use displacement with Cycles?

Add a glow effect in 2D editor like Gimp or Photoshop:

Next, create normal map using this image (in GIMP - normal map plugin)

Normal map gives mach better result:


BGE: realtime random shape generator (python)

I have modified the code as follows :

added a dictionary that stores the vertex position and the generated offset by random.uniform()
for each vertex check if there is already an offset for this position , if so we add this offset to the old position
if there is no offset calculated for this position we generate a new one and store it in the dictionary, we also add it to the old position

this method gives the vertices that has the same position  the same offseet

from bge import logic
import random
from mathutils import Vector

cont = logic.getCurrentController()
object = cont.owner

for mesh in object.meshes:
   print(mesh)
   verts_shift = dict()
   for m_index in range(len(mesh.materials)):
      print(m_index)
      for v_index in range(mesh.getVertexArrayLength(m_index)):
         print(v_index)
         vertex = mesh.getVertex(m_index, v_index)
         xyz_old= vertex.getXYZ().freeze()
         xyz_shift = verts_shift.get(xyz_old, None)
         if xyz_shift :
             vertex.setXYZ(xyz_old+xyz_shift)
         else :
             xyz_shift = Vector(( random.uniform(-0.5,0.5), random.uniform(-0.5,0.5), random.uniform(-0.5,0.5) ))
             verts_shift[xyz_old] = xyz_shift
             vertex.setXYZ(xyz_old+xyz_shift)

         print(xyz_old, xyz_shift)


How to use a material node data path as driver, that is located inside a material group?

With blender 2.81 and up you can right-click in the field and choose "Copy as New Driver", then right click in the driven field and click "Paste Driver".

The resulting data path (in my file anyway) :


How to make blender listen to a commandport so other apps can send code to it?

In short: AFAIK Blender doesn't come with such a feature built-in.

You could start an HTTP server and listen to incoming requests. You'll have to use multithreading (can get hairy) if you don't want to block Blender's UI, though. Another approach could be an asyncio socket server. Also see this SE question: send instructions to blender from external application.

Be sure that you only run this on trusted networks, though, and/or use proper encryption & authentication to protect your Blender.


Add shortcut for Merge Last, and Merge First

The first step is to find out what command is being called when you
merge 2 vertices. You can find that out by doing a merge, then checking
the info window at the top. You can see me do this in this GIF:

From here, I know the command I want to activate is
bpy.ops.mesh.merge. Now all I have to do is map a shortcut to this
function. This can be done pretty easily without scripting.

Go to File > User Preferences > Input > 3D View > Mesh
Go to the bottom and click Add New.
Click the drop down next to the "none" label for the shortcut you
just added.
In the text input box where you see "none" written, change it to say
mesh.merge.
At the bottom you should see a property show up that's grayed out
that says "At Center". Click that drop down and change it to "At
First".
Use the buttons on the right side of this dialog to make the shortcut
that will activate this function. In my example below, I have decided
to use Ctrl Alt M

Be sure to save user settings if you want this shortcut to be active every time you open Blender.


You can use Object ID Keys to get the initial transform values of your objects. Put the node in a loop subgroup to get the Initial Position of your objects.

Look at the example usage.


Grease pencil onion skin not showing in draw mode 2.81 but works fine in 2.80

I realize this is an older question, but I found this while having the same issue. I discovered that for me the problem was that I was in the render preview viewport shading mode. Onion skinning worked in ever viewport shading mode except that one. Hopefully that helps someone else.


How can I select all the keyframe for an object or many objects?

I believe I found a close answer. Since Google was no help, I click on all the buttons. I found butted that looks like mouse pointer on dope sheet bar and it is called "Only incude channels relating to selected objects" and if you click that you will only see keyframe for selected object or objects. So if you select object first then click button you can then select all and only get the keyframe for selected object or objects. If no one post a better answer in couple days I will select this as the answer.


You can just increase the resolution of the curve:

I also see that you are using a NURBS path with several extrusions to form the simple curved road shape. Curves are designed to help artists interpolate between control points so they don't need to manually add dozens or hundreds of them. Try to use as few control points as possible.
I advise you to use bezier curves, as they offer users much more control over the shape. Here is what the road (I assume it is a quarter circle, I might be wrong) would look like. I added a primitive Bezier Circle and deleted the other 3/4ths of it.


How can I select between different UV Maps?

Go into the mesh data tab and select the UV map you wish to be active


Weird distortions when rigged object collides with itself

Thank you! The problem seemed to be I had removed the edges to reduce polygon count. I rigged my older model and the problem wasn't there.


In blender render,

Goto>render settings

Tick>Freestyle

Then Tick>Freestyle SVG Export

Go back to>output
Choose a file to place your rendered work

Then hit>Render

Your SVG is ready at the specified output location

Additionally,
To prevent some object from rendering as SVG,
On the material tab, just click on Transparency


How to animate Texture change in Blender Internal

You may shift textures animating the Offset value of the gradient texture, which works as a mask for transition between two textures.

Prepare two different textures.

Add a new material to your surface and unwrap it. Give it two image textures (set their type to Image or Movie and mapping coordinates to UV). Now add one more texture. Set its type to Blend and place it between previously added ones. In Influence panel uncheck the Color box and check Alpha. Check the RGB to Intensity and Stencil boxes.

Now the gradient texture acts like a mask. In Colors panel check the Ramp box and use sliders to define the smoothness/sharpness of the transition between textures.

In Mapping panel change the Offset value of the X window so you can see only one texture. Hovering your cursor over that window press I to insert a keyframe. Go to another frame, change the Offset value and press I again.


How to limit the rotation of knees, feet, ankles and similar joints?

Edit:
In looked back at this old answer and realized you were using an IK rig. To limit this, there is an inverse kinematics section to the bone properties.

Select the bone you want to constrain, and make sure you are in posed mode. There should be a bone constraints window:

By check boxing 'limit' you can set a bone to only bend so far in IK mode.

_________________________

  Old Answer

You can add a "limit Rotation" constraint, as you can see set up there.
It also has other bone limitations; go ahead and mess around with it.


Animating a bone to turn 360° doesn't rotate correctly

I guess if you keyframe it in the 3D view it won't interpolate correctly because either it doesn't know in what direction it is supposed to go or Quaternion interpolation is messy, don't ask me why.
The easiest way to do it is to use the N > Item > Transform panel, switch Quaternion to XYZ Euler, and keyframe a rotation of 0/0/0° at frame 0, and 0/360/0° at frame X (I keyframed the bone in Pose mode, if you want to keyframe the armature in Object mode it will be 0/0/360°):