Simulating actual airflow and pressure would require complicated fluid dynamics simulation - but you could simulate the effect using Soft Body physics.

Create you mesh and add Soft Body in the Physics properties.

Select the vertices that you want to tie to a fixed point (eg, the ground) and assign them to a new Vertex Group. This will be used to pin them in place so that the mesh is anchored.

It is then just a matter of adjusting the Soft Body properties to get the desired effect, simulating the lack of air pressure by reducing the Soft Body Edge Spings and applying the pressure/air flow by increasing the Edge Springs.

The Soft Body Goal pins vertices in place - set the Vertex Group to the group created to act as the 'anchor' and increate the Strengths and Stiffness to force them to stay in place (otherwise they'll be allowed to drift from their start points).

Decrease the 'Bending' Soft Body Edges setting to allow the body to collapse and increase it to "inflate". You may need to adjust the other settings to get the desired effect.

To prevent the mesh from collapsing too far, set the Edge and Face collision checkboxes and enable Soft Body Self Collision. You might want to change the Self Collision settings to prevent the mesh folding too far into itself and/or change the Soft Body Solver settings for a more accurate simulation if it's behaving erratically (eg, reduce the Error Limit).


How to create a curved surface from a sharp edge?

It is a bit difficult to visualize exactly what you actually want based on your wording of the problem but If I understand the problem correctly, what you want is a curved surface. You can achieve this by just bevelling a sharp edge,

You can take a sharp corner that connects at a 90° angle…

…and then bevel the edge using Ctrl + B and increase the segments to round it into a curved surface.


You need to set you Samples (of the render option) up very high (minimum of 300) to get of "Fireflies" (the name given to these pixels). Note: This will increase render times quite a bit.


Follow Active Quads will extend the selected mesh UVs depends on the angle of the edges of active Quad.

Unwraping a mesh that doesn't have a UV map will set the active face mapped to the full size of the UV window and extent the rest of the faces accordingly.


Access color channels independently of alpha with Cycles?

With the Image texture node selected in the node editor, enable the Options panel (N) and turn off the Use Alpha radio button. Use a separate RGB node if you want to use individual channels. If you need the texture with alpha too, then add another Texture Image node and use it with alpha this time.

I hope that helps.

Alex


Is there a way to save my current studio lighting in blender 2.8?

Just create a scene that has the elements you want.

Save the scene as the default scene.

File>Defaults>Save Startup File.

Next time you open blender, your lights will be there.


Found the solution: The labeling in Blender is apparently wrong. The right command is bpy.ops.mesh.select_all(action='INVERT')


Do unconnected nodes increase render times?

Nope
They Don't Increase any render time as the lights in the scene are not scattered according to the unconnected nodes so it will not have any effect on render time but can make your blend file slightly heavier by size


Geneal Question About Creating an Add On

Are you sure need it to be an addon?
Otherwise you can use Compositor Color key node to create mask from color, and then color mix node to mask out textures:


Can't animate keyframed node properties with f-curve - they are disabled

Select current node, that you want to edit in f-curve editor:

or unclick  only include channels related to selected objects and data (icon with mouse pointer)

This features restore to default state:


You could try the following:

Select the floor
Go to the Properties panel
From the tabs, go to Object (looks like a cube)
In Ray Visibility, click on Glossy check


append shader⊶node group from another blender file - in update style

AFAIK There is no direct link back to the node group in your template file once the group is appended so what you would have to do is appending the new group and replace the data-block of the old one:

You might want to use python to automate this process for all materials within the blend file:
import bpy

D = bpy.data

for mat in D.materials:
    if hasattr(mat.node_tree, "nodes"):
        for node in mat.node_tree.nodes:
            if node.type == 'GROUP':
                if node.node_tree.name == "Template v1":
                    node.node_tree = D.node_groups['Template v2']


Texture painting with flow, hardness, density

The patch still has yet to be reviewed properly after the suggestions Campbell made on initial review, and there are actions requested because the code system for paint affects several modes in the unified paint system. There are instructions on building blender to include patches in the build, but those instructions don't appear here on BSE - I see from a previous search that asking about how to build blender is off topic here. That said, I see from a google search that there are many options covering the different OS available.


Blender only rendered one layer in animation

You need to change your ouput format to OpenEXR multilayer.
After that you can access the different layers by adding an image node and changing the renderlayer like shown below.

If you want to use the sequence in an external compositor like nuke this should not be a problem. the channels are named according to the renderlayers (e.g renderlayer001.z).


How can we change the particle size in Blender 2.8?

you can change particle size from the Render drop-down in the particle properties or by scaling the instance object itself.


You could also use IK-Constraints to control the legs.
Add a plane as Targets for each leg so the legs can be moved around with them.   To control the rotation, empties are used as Pole Targets
The Legs are parented to the body.

Demo .blend


Boolean Modifier Issue. Object 1 wont cut through object 2 for some reason

Your meshes are positioned not properly and have geometry unsuitable for Boolean to work - flipped normals, doubles.

Problem 1. Position of objects

In your file objects are placed one inside of another. The modifier will work (under certain conditions) however you won't see any result (because the result of this operation will be only a copy of object, which was expected to be cut off, located inside of the main one).

Solution
Place object to be cut off appropriately; generally you want it to create an indentation somewhere in the main object, so move it out of main object as much as indentation should be. If you want to cut through the other object (so to "break it into 2 pieces) then scale up the one which is used for cutting appropriately.

Problem 2. Normals

Normals of the objects are pointing in the wrong way.

Solution
In Edit mode select all and press Ctrl+N; if nothing changed choose Inside in the Last Operator panel or press Ctrl+Shift+N.
From manual:

  The face normals are taken into account for the calculations.

See also Why are some faces in my mesh darker? for more info.

Problem 3. Doubles

There are double vertices in the mesh which prevented normals from being recalcualated successfully.

While Boolean, oddly enough, will work without this being done, it's best to get rid of them because of possible problems furthermore.

Solution

Select all > W > Remove Doubles.

Result

Applying transforms

Scale and rotation aren't applied to both objects. While Boolean will work with that, it's best to apply them to have expected result of work of modifiers. See Why is it important to apply transformation to an objects data?.

Optionally: fixing topology

Listed above is enough to make Boolean start working. Generally you would keep track of topology of objects though, because Ngons can be treated differently in different circumstances (still there are cases when they can be good).

As from manual:

  The target topology determines the new topology of the modified mesh.

In your model top faces are Ngons; it's better to not leave this:

and tend to create something more like grid:

It can be easily done with insetting face with I and converting Ngon into grid of quads by filling it with Ctrl+F > GridFill.
Same applies to both sides of both meshes.

More reading:

Boolean modifier not working
Boolean modifier (manual)


Answer is actually quite simple: this cannot work in current design - to simplify, objects as particles are not actual objects, but instances of objects, with quite limited sub-set of objects features. An instance cannot emit particles.


Unable to bake fluid after changing cache folder

I had the same problem. I had a special character (german ü) in the path of the blend-file, after removing that, everything worked fine.


How do I make an object attract another object?

What you could do is: Create a floor, a cube, a ball. The cube and the floor are Rigid Body, Type > Passive. The ball is Rigid Body, Type > Active. Into the cube, create (A) a Force Field > Force. In the Physics tab, give it a Strength of - 100 or whatever negative value. Play the animation, the force field should attract the ball.


It seems Extrude followed by a a CRTL-B bevel where subdivisions are set with the mouse wheel

btw it was also asked and explained in comments under the video...


Splitting Blender animation into separate clips

How to create a new action

Press the F-Button so it is darkened to keep your existing action in the blend file even when you save and reload it. Otherwise you might loose your animation. So in case you're uncertain make a backup copy.
Press the  button to unlink the action.
Press the New button to create a new action.

Copy frames from one action to another

Switch between your actions by pressing the  button and choose your desired action from the dropdown menu
Select a frame range by pressing the B key to activate the border select and select a range of frames in the dopesheet editor.
Press Ctrl + C or press the  button in the header menu to copy frames to a clipboard
Press Ctrl + D or press the  button in the header menu to paste the frames at the current cursor location (green line)


You have 2 different sampling ratios, available in the Properties menu > Render > Sampling > Samples:

the Preview is the ratio used when you work your scene
the Render is the ratio used when you launch a definitive render of your scene (either single image or animation when you click the Render or Animation button on the top of this Render menu).

You can decrease the Preview quality so that it takes less time to render when you work, for example 3 may be enough.

The Render ratio depends on what you want as a definitive result, you can begin with 100

In the next version of Blender (2.8), the Eevee render engine seems much faster than Cycles, it will generate a high quality image in real time, but the result will be slightly different


Different Color When Rendered? (Not Material)

You need to reset your normals, go into edit mode, select everything A, and hit Ctrl-N.

This happens when blender incorrectly guesses which way the face normal should be pointing when you make a face, it happens from time to time.


No sound after export blender game in .exe? How to export with sound?

Blender does not bake any audio into the executable, it just stores the path to the files.

To ship the game with audio, put the audio files into the same folder as your .blend file (or a subfolder) before you load them into your game and when you open them in Blender make sure that 'Relative Path' is checked.
After exporting the game, just copy all audio files to the folder of the .exe (or a subfolder).


Trying to bevel a circle along a path, and getting a flat papercli[p

Found the answer.  On my SVG curve, I made sure I converted the points to smooth points (the ones with handles) but I neglected to change the first point.  It was just a point (no "vectors", if that is correct).  Transforming that point to a vector/smooth curve point worked!


Its as Moonboots says, you need to slightly bend the bones forwards before you use IK constraints


Fixed - even though the "hair shape" doesn't directly affect the appearance of the individual strands of grass, it apparently was affecting the shadow. I just boosted the tip thickness, and radius scale of the particle emitter.


Select all faces within an area delimited by sharp edges

If you can easily select one row of faces around the island then the hard part of the issue is solved.

Just select that single face loop and hide it with H, then select one of the remaining faces at the center of the island and select all linked with Ctrl + L.

Unhide the hidden loop with Alt + H, and it should include it in selection automatically


How do you set the scale or size of the work area for modeling objects?

If you want to change the way blender tells you the units from for example "meter" to "millimeter" or "centimeter", go in the "Scene Properties" under "Units". Select the system you want to use, either "Metric" or "Imperial".
Further down you have the option to select the length unit, as mentioned for metric like "meter" and "centimeter".


3D in XAML is pretty much a dead since Microsoft dropped support for it.

I rewrote the script from scratch. You can the script from my GitLab page which includes install and usage instructions as well as the license (MIT).


Attach vertices of a mesh to another mesh's vertices

Actually, I ditched Hooks and used Armature approach due to easier maintenance. Result:

General idea, lower cube is parent, upper - child:

To do so, add Armature object and create bone in edit mode right at the desired point of a control/parent object.
Add new vertex group and name it after corresponding bone.
Add Child Of constraint to the bone and select parent object as target and vertex group for geometry control. Click Set Inverse to eliminate excessive offset.
For a child object (upper cube) also add vertex group with the same name but another vertex. Both objects in edit mode:

Final step - add Armature modifier to the child object and choose armature object.


How can i change the background from my animation in compsitor?

You can change the color of the background in the compositor with the environment pass and either an alpha over node or a mix node.


Where did newtonian size setting go in 2.79a

It was "consolidated" under the Render panel in 2.79a

In 2.79, particle size appeared in more than one panel, which caused issues.

See

https://lists.blender.org/pipermail/bf-blender-cvs/2018-January/103452.html

for more details.


How to connect sharp edge with smooth one?

All you need to do is separate the edge loops on the side you want smooth. Think of it as the opposite of proximity loops, where proximity loops make edges sharper, spreading out the edge loops will make it softer.

Simply select the vertices on the side you want smother, and press GG to edge slide them in to place.
If you get any shading artifacts, switch to side view and make sure all the edges and vertices are aligned. Scale to 0 on (an example) the Z axis to re-aline. For example, if you lowered one of the vertices, that will create a dip in the subdivided mesh and break the smooth look.

The vertices I moved are selected in this image.

Edited mesh in object mode


How to create 2.35:1 movie with no stretching?

To use a video strip's original resolution without any stretching, activate the strip's Image Offset. Change the setting's X  and Y value to offset the video image's position in the overall image.


You need a Glossy shader for this.

Open a node editor.
Go to the material tab (in the first set, looks like a ball), and then make sure you're in the object tab (in the second set, looks like a cube).
Select (right-click) the Diffuse BSDF node.
Press Shift+S and switch its type to a Glossy BSDF.

This will give you reflections. You can play with the reflection color and roughness until it looks right.

See the manual for more information on Cycles materials.


Change between layers using shortcut in blender 2.8

In the editor type (view Layer) you can press the eye symbol of a collection while holding ctrl to isolate that collection (hide every other collection but that). Sorry I would just comment since I'm not sure that is the answer you where waiting for, but I'm not allowed to do so yet. Hope helps.

Otherwise, every collection corresponds to a number, so you can cycle through collection by pressing the numbers.


You can construct it out of primitives making sure the forms to be connected have the same amount of edges, use solidify(ctrl+f->Solidify) to add thickness and insert edge ring(ctrl+r) to subdivide the primitives and delete unnecessary geometry, then you can select the edge segments and bridge them(w->Bridge Edge Loops). You can choose Blend Surface as surface interpolation and add some cuts for the bridge to have smoother shape. You would have to fill the holes using fill(f) and various other tools. F2 add-on will be very useful - just enable it in add-ons tab of user preferences(ctrl+alt+u).


Select the mesh and press the period key on the Numpad.


Script to UV split and translate dynamically

To invoke the operator as if you pressed the G key you can simply do the following:
bpy.ops.transform.translate('INVOKE_DEFAULT')

Note that you have to have your mouse cursor placed in the correct area.

This works according to the documentation of Operators/Execution Context:

When calling an operator you may want to pass the execution context.
This determines the context that is given for the operator to run in, and whether invoke() is called or only execute().
‘EXEC_DEFAULT’ is used by default, running only the execute() method, but you may want the operator to take user interaction with ‘INVOKE_DEFAULT’ which will also call invoke() if existing.

The last sentence is crucial. Operators like translate that run until the user confirmed further inputs (keystrokes and/or mouse movement) are called modal operators. They have to be invoked for them to take user input, else you have to give parameters.
Note: Possibly something interesting for you is that you can override the context of an operator (the area it is run in) to be the UV editor. You have to call the operator as
bpy.ops.transform.translate('INVOKE_DEFAULT', {'area': areaoverride})

where areaoverride is one of bpy.data.screens[idx].areas with any valid index idx.


Should I remove hidden geometry on a model for use in a game engine?

Going for a pretty general answer here, bear with me or skip to the end if you just want a yes or no.

So, while most if not all engines will offer some form of culling (not rendering/using what is not seen) you will still see detrimental drops in your framerate if your model has a significant polycount. By itself when testing you might be fine yes but games are meant to be dynamic and when you throw particles, physics and post processing in the mix it's a lot more for your system to process now.

For a quick example, fire up Blender and add the default cube, right click and select it, it is selected instantly! Now subdivide it say 10 times, add a subsurf modifier and set the view level to 6 and try again. It takes a while, this is a rather exaggerated example but it's more or less what your engine which is also a 3d software does as it has to iterate over the vertices in the mesh. Now imagine doing that on a moving character and having to do matrix math for every frame to calculate the new points for vertices to be at.

Even if your engine does support culling or some other magical algorithm to discard hidden geometry or automatic level of detailing (LOD) you would still most likely be hit with load times at some point whether when launching your game for the first time , loading assets or saving depending on how you go about it.

"Real" world example now, if your model has 100, 000 vertices, this is what is loaded into your engine of choice, if your armor is 20, 000 vertices and covers say 50% of your characters body. Your final polycount would be 70, 000 vertices instead of 120, 000 if you delete the hidden parts of the character model.

In any 3d modelers workflow there is usually an entire step dedicated to this called retopology where the simplest base mesh that can support the high details from a much more detailed and higher poly count model (usually sculpt). See https://cgcookie.com/course/introduction-to-retopology/

Even better, if you can generate normal and or displacement maps you can also see your polycount drop even more significantly. This is what pretty much every game studio does. If you're making a game you can't imagine that everyone will have a "good" machine to run it and most games ship with several different models depending on the resolution and or settings you are playing at.

For example here is a somewhat popular and funny screenshot of Skyrim being forced to run on the lowest possible setting. In game detailed grass and tree leaves are merely planes and that shiny detailed axe is a blob with some good textures.

Counter Strike Go

So in conclusion, people will try every trick in the book for lower geometry while still having a good look so if it isn't being seen and you can animate or get a similar effect, remove it.


There are many ways to do what you want.
Here are a few ideas:

Use a hue correct node, where you can select the color very precisely and change the hue (or saturation).

Use a chroma key to create a matte and then use that information to combine two differently colored versions of the same image.

Or use a mask to control the mix.


How to achieve a stylized burning (Wireframe) effect?

Create a Cube or use default object and apply a Wireframe modifier.

with the cube selected go to the Physics properties panel and turn on Smoke. Set the flow type to Flame and Flow Source to Mesh (not particles).

Add another cube around the first one, this will act as the rendered domain object.

Set the volumetrics as follows, be sure to turn on Adaptive Domain to reduce processor load.

Go to the Domain object's material settings and set up the Blender Internal values as follows or look for Cycles nodes instead. If in doubt create another cube then select it and perform a Quick Smoke effect. Then you can use and modify the automatically generated material on your object.

It should look like this:

To change the nature of the flame (but not it's shape), you can change the density of the Domain Object's volume material and the texture blend in the texture properties


Is there any significant difference between 2.67 and 2.73 in terms of 3D printing?

If you are just starting with blender, the DVD in question should give you a good idea of how things work, and you should be OK using current versions.

While some things have indeed changed since version 2.67, the main structure of the blender's User Interface has not. Blender has been very good in terms of keeping backwards compatibility, except for versions previous to 2.5, where a major overhaul did take place. But even that overhaul was to the UI, and files created in older versions open and can be edited in current versions. Note though, that if you're using a current version of Blender, you'll want to use the box in the lower left of the files dialog screen that allows one to open the file without changing the UI; otherwise, when you open a file, one sees the UI with which the file was created.

If there are things that are dramatically different on newer versions, like plugins that are not up to date, or you just can't find the tool in today's version, don't worry, you can still download older versions of blender here: http://download.blender.org/release/ .

Once you get a general idea of how blender works you'll find that newer versions are quite a bit better, with less bugs and much easier to use than previous ones. And if you get stuck... you can always ask questions here or in other forums. Happy blending.


It is basically answered here:
How to evenly space vertices?

But for parallel edgeloops you need to set "Input" in Looptools-Space to parallel(not selected) in order to function.

Thanks to Ray Mairlot for clarification.


Combining Black and White with Color Rendering

My solution was as follows:

Riffing off one of many excellent tutorials by OneMinuteVideoTutorials on YouTube, I used a plane with a transparent material that I linked to a Material ID in node editor.

The first step is assigning the transparent material a Material ID (Material > Settings > Pass Index), and then enabling Material Index passes (Render Layer > Passes > Material Index).

The effect can then be achieved using the following combination of nodes:

Notice that the effect is contingent on the saturation in the Hue Saturation Value node being set to 0.


Texture or colour only on the displacement vector

You can just add in a mix node, another principled shader and a color ramp.

Create a 2nd principled shader (this will be your lava).

Connect it with a mix shader, use a color ramp and have your displacement nodes connect to it.

Then on your color ramp adjust the flags to your liking.


Animated robot without bones behaves strangely when exported to Unity

Blender does export object transform animations as .fbx, without using armatures, but you need to export them as a .fbx explicity. Those animations should be done in a NLA window instead of an Action window, and then select the object and export only selected as fbx. The animation will have the length of the scene timeline and will run just fine once inside unity.


Thank you so much. I'm not sure how my unwrapping had a square that covered it, but once I edited the UV to scale the giant square into a tiny one and put it somewhere not overlapping it worked resulting on a complete normal map.


Mirror Modifier mirrors object incorrectly

I am not entirely sure why you would use a Mirror modifier there. The mesh is not mirrored so you can't "put them back together". When working with a Mirror modifier you only create one half of the shirt and use the Mirror modifier then to generate the other half. You created a whole t-shirt and mirrored it. Why would you even want to apply the Mirror modifier now?

If you want to get a perfectly symmetrical shirt you have to do that from the beginning by creating only a half of it.

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

I hope I could help.


Absence of snapping (coordinate matching) in nested platonics

With snap always set to 'Vertex' and 'Active', Pivot at '3D Cursor'. All transforms in Edit Mode, with all vertices selected, and a convenient vertex active. Usually you will translate-snap the active vertex into place, put the 3D Cursor there, and then with another vertex  roughly opposite the cursor made active, uniformly-scale or rotate all the vertices about the 3D cursor.

All objects created from Extra Objects > Math Function > Regular Solids

Dodecahedron to Icosahedron: AltP Poke all faces of the Icosahedron, scale all vertices of the dodecahedron, snapping the active vertex to one of the new face centers
Cube to Dodecahedron: scale the cube and snap the active vertex to one of the corners of the dodecahedron
Tetrahedron to Cube: the solid can be snapped, by  progressively moving the pivot point and setting  Custom Orientations, but easier to snap individual vertices of the tetrahedron to the appropriate corners of the cube.
Octahedron to Cube: poke the faces of the cube, and scale, as we did with the dodecahedron.

What Blender's snap system is missing (compared to some other 3D applications,) is the ability to set a snap orientation. You can constrain the transformation of the snap source, but not the vector from snap source to snap target.

But, given that, sure you can snap during rotations, scales, and translations, constrained ones, if you like.


How do you link to documentation via an operator

In the file  2.77/scripts/startup/bl_operators/wm.py you will find all the wm.doc_* operators,

class WM_OT_doc_view_manual(Operator):
    """Load online manual"""
    bl_idname = "wm.doc_view_manual"
    bl_label = "View Manual"

    doc_id = doc_id
    ...

We can override this operator to call our own.  Here the doc_id is

import bpy
from bl_operators.wm import WM_OT_doc_view_manual, doc_id

class Overide_doc_view_manual(WM_OT_doc_view_manual):
    doc_id = doc_id
    def invoke(self, context, event):
        print("Invoke")
        return {'FINISHED'}

    def execute(self, context):
        print("Online manual", self.doc_id)
        return {'FINISHED'}

def execute(self, context):
    print("Called myClass")
    return {'FINISHED'}
# lazy register
bpy.utils.register_class(Overide_doc_view_manual)


How to make the texture not follow the mesh deformations (Bouncing and stretching ball)

So I got the solution. I used lattice to deform the mesh. However if you rotate the lattice in edit mode, the texture will follow the mesh. But if you rotate the lattice in object mode, the texture doesn't follow the mesh. If you rig some bones to deform the lattice, and have them rotate the lattice as well, the texture will follow the mesh again because the bones seem to rotate lattice points, not the lattice object. However if you rotate this armature in object mode, it will rotate the lattice as object as well. What I did was, I used a second armature to rotate the first and consequently the lattice. I also hooked up the lattice deformation bones in the first armature to copy the location of some bones in the second. This meant I can deform lattice points as well as rotate it as a object in one armature/rig.
I am not the best at explaining so I'll link the files here if you wanna understand how to do this.
Here's the first file that I was struggling with. In this file the texture follows the mesh and is not independent: https://blend-exchange.giantcowfilms.com/b/lgJWddwp/
Here's is the file with the problem fixed. In this file the texture doesn't follow the mesh and can be controlled independently from the mesh deformation: https://blend-exchange.giantcowfilms.com/b/en23nWJl/


I suppose you are making the animation in the Video Sequence Editor so you could add a white strip in the background.

Shift + A → Effect strip → Color.
In its properties (n) go to Effect strip section an change the Color to white.
Render again.

Maybe you need to select the Alpha Over mode in Blend option of the strip with your image sequence so it uses their alpha channel.


You have to build this with Blender.

It is located at /blender/release/datafiles/splash.png — (old svn link) (new git link).

Just replace1 this file with a similar one.

1Here is a link to the entry on the wiki on how to correctly change it.
You can grab an old template here which should still work and size your image accordingly (src). The template is also in the same directory as splash_template.xcf
BlenderCookie has a tutorial on building Blender (download from archives) in which the author changes the splash screen. (He uses mac but the majority of process can be done pretty much the same way for other platforms)


How to demonstrate Archimedes Law in Blender?

If this is for teaching purposes, you could, instead, illustrate the following thought experiment:

From a perfectly accurate spring scale, dangle an infinitely thin string. The scale shows zero.
Dip the string into a glass of water.The scale still shows zero.
From infinitely thin, weightless material, construct a 1cm cubed box attached to the end of the string, underwater. The scale still shows zero.
Lower the glass. the scale now shows 1 gram.

The upward force on the box of water, while it was submerged, must have been 1 gram.

This, IMO, has the advantage of showing why the law applies, rather than simply demonstrating that Blender can simulate it.


Use Pose Mode or Object Mode to move whole model

If you are just doing all the animation on the armature (pose and object mode), then I see no harm in that. In fact I think there is a little benefit over animating it all in pose mode.

Here I have the X axis movement key framed on the armature object (it is 40 frames long). The small bounce along the Z axis is keyframed on the bone in pose mode (its animation only lasts 10 frames). Doing it like this enables me to separate the animation, and keyframe the bounce in local space, and then use a Cycle modifier in the graph editor to make it loop.

However if you are animating the mesh object too, then that is a problem.
The reason for this is because of the way parenting works in blender.
See parenting is one way, meaning that you can move the parent (the armature) and both will move, but if you move the child (the mesh object) it separates from the armature. When you bind an armature to an object you are parenting it among other things.


How to use Overlay layer in Grease Pencil to show drawing only over desired background

Here the basic typical setting -

we have three layers here,

set the top layer to ("blue square" in this example) Object data > layers> Blend = Overlay.
toggle the Clamp option for the layer below (in the layer rubric or next to the Opacity option)

you can see that the red circle is visible only on top of the green oval, but not on the blue background.
note that the red color changed, due to color mixing, you may adjust it.

Now I used this setting to set a blinkable eye:

I used the former setting, and -

I placed layers to not be effected, above the overly
I placed the 'pupil' layer under the overlay, but above the 'eye.white", and toggled the Clamp option.

Now when I scale the eye.white shape vertically, I get the blinking eye effect.
It can be animated too.
Note that now layers partly covered under the overlay (like 'neck') would not be covered as regularly, it is a bit of a problem, you may separate it into to two different objects.


Can I render isolated objects but keeping all the impact of other objects and their materials?

You could use the Indirect Only restriction toggle option. It's only available for a whole collection. If you enable it, it will hide all the collection's objects but they will still affect the rendered ones.

Or select an object and disable its camera visibility in the Properties panel > Object > Visibility:


Is there a list for blender build-in attributes?

There will be an attribute search included in blender soon.
source: Blender daily
( https://youtu.be/4pPSsAuM8sQ )


It looks like you may have selected Wire as the material type:

Try selecting Surface instead.


This may not be the answer you're looking for, but I'm pretty sure it has to do with how Blender interfaces with the GPU and how the Windows kernel reacts to that.  When the OS gets an interrupt requesting the GPU, it's put into a queue until the GPU becomes available.  When Blender gets assigned the GPU, it doesn't let go of it for an eternity in processing time... say, 60ms or so.  During that time, the Windows Desktop has to wait on Blender before it can update.

You obviously know that the most efficient way to render is by keeping the GPU load as close to 100% for as long as possible.  In order to do this and keep the monitor updating the screen, lag is introduced when the GPU becomes unresponsive for short periods of time.

When the driver becomes unresponsive to the Windows kernel (i.e. when Blender is using it)... it must wait until it responds.  You can see this when you enable Branched Path Tracing in the Sampling options.  If you set the samples too high, the GPU will become unresponsive long enough that Windows will actually reset the GPU driver and crash Blender (the operating system doesn't like when it's not sovereign over the affairs of the PC).

The point is that Windows is monitoring this.  When the Titan is your primary display and it goes unresponsive, the OS takes it's cues from that driver for the desktop display.  In other words, if Windows can't display the desktop at 60Hz refresh on your primary monitor, then it won't on the others.  I'm pretty sure Windows uses a complex queuing system for sending and receiving messages from the display adapters to keep them all in sync.

I don't have multiple monitors but I have multiple GPUs.  When I render with the two GPUs that are not hooked to my monitor, I get zero lag, and I'm running Windows 7.  You can try using the 770 as your primary and render using the Titan, but if my guess is right, if Windows is using the Titan as a display device, the 770 will also lag.

Maybe someone else will have a more promising answer/solution.  It's possible that Microsoft changed the way that it handles multiple displays in version 10, but I have no experience with it.


How can I make a rounded indentation on a cylinder?

Though you may do it using Boolean Modifier (or BoolTool add on) the good solution here may be using an Inset tool since it'll allow you to make a clean topology mesh.

Add a cylinder with 16 subdivisions. Add edge loops Ctrl+R to define the indentation position. Select the faces representing the indentation and press I,B (to enable Boundary mode). Repeat it twice (to create the extra edge loops for subsurf creasing). Extrude it inwards (E), then inset again as before.

Add the additional edge loops to the indent, then form its shape transforming some vertices. Finally fill the top part of the cylinder with mesh (example topology pictured in the first .jpeg).


You can unwrap individual segments, then using P button to add some pinned vertices in the UV/Image editor to control the shape to match the wave texture while using Live Unwrap.


Pixelated error on select faces during Render

So it was definitely a duplicate face, but the bad face had some strange properties. I had to delete all the bad faces and start over. I created the issue again by subdividing the edge and creating a new face with the new vertex. Still don't know why.


Why doesn't this lightmap capture the correct shadow?

I got it now. The problem was that the floor and walls had their normal flipped. After I checked backface culling, this became obvious. Fixing the normal direction solved the problem.


Material animations not working with property?

You need to activate the action actuator after changing the property. The above image shows you activate it only when setting the property to zero.

I suggest you connect the fourth controller with the action actuator too.


Colors from imported image in compositor aren't displaying correctly

Set the color space to sRGB in the image node (or the UV/Image editor) and also enable view as render. In the color management section set the Display device and Render View to sRGB


Scripting: Is there a way to test if an object has shape-keys?

Access shape key data via the object.data.shape_keys object, and the actual shape key blocks through object.data.shape_keys.key_blocks collection:

import bpy
# Reference active object
o = bpy.context.object

# Check if object has any shape keys at all (will be None if not)
if o.data.shape_keys:
    num_of_SK_blocks = len( o.data.shape_keys.key_blocks )
    print( "Number of shape keys: ", num_of_SK_blocks )


Texture not displaying properly in any mode except Texture Paint

Fjoersteller's comment:

Actually I think there is no need to re-upload. : ) Go to the Settings in the Material Properties tab of you material and. Under Settings you should set both Blend Mode and Shadow Mode  to Opaque. This should fix you problem.

Thanks Fjoersteller, that actually fixed it! I had Blend Mode on Alpha Blend, but turning it to Opaque fixed the texture completely!!!


Can't move nor scale the mesh in Object mode

Maybe you are talking about the "X Mirror" option?

And... yes, about object mode, transformations are locked:


It's easy to turn a rigid body static and back again. Start with a rigid body, and then you can suspend/restore the dynamics:

import bge

cont = bge.logic.getCurrentController()
own = cont.owner
own.suspendDynamics()
#OR
own.restoreDynamics()

A slightly more hacky way to turn a rigid body static is to set it's mass to infinite (ie no force will have an effect).

import bge

cont = bge.logic.getCurrentController()
own = cont.owner
own.mass = float('inf')

To make it rigid body again, set it's mass back to a proper number

To make an object dynamic is hard as BGE doesn't have access to the inertia tensor/radius of gyration. Even setting the angular velocity cap to 0.0 doesn't work. I guess you'd have to, every frame, set it's angular velocity to zero and restore it's orientation.

(untested code):

import bge

own = bge.logic.getCurrentController().owner
if 'ori' not in own:
    own['ori'] = own.worldOrientation.copy()
own.worldOrientation = own['ori']
own.worldAngularVelocity = [0.0, 0.0, 0.0]


Add-On Dev: Operator Window - Open/Close events?

I think I can safely say these are reliable, for a couple reasons:

They are reliable for modal operator classes, and there is little difference between a modal operator class and a non-modal operator class, except for a specific function being defined and returning certain values from specific functions. It makes sense that the constructor/destructor can be relied on for all operator classes.
See https://docs.blender.org/api/current/info_overview.html (thanks to Brockmann for updated version link) .. If you look under the section titled class mix-in example, it states the following:

"Notice these classes don’t define an __init__(self) function. While __init__() and __del__() will be called if defined, the class instances lifetime only spans the execution."

If anyone can confirm or has any reason to think otherwise, please let me know. Thanks!


How to achieve softer and more realistic lighting from a chandelier?

Given the vagueness of the question I'll ramble a vague answer:

Reproducing light sources in blender (or in any photographic device) is a bit problematic: in order to get the level of brightness that we associate with them perceptually the emitters get so bright that they are just white with no detail.

Or if we want to get the detail on them there is not enough light on the scene

(more on the subject on this question)

The shadows produced by the glass can be less dense if you increase the samples and the number of bounces for transparency and transmission (note that your rendering time will increase dramatically)

Another trick if you don't want to render for such a long time is to have the glass be completely transparent to the light (maybe less realistic but will cut your rendering time)

Yet another option is to add an object that will light the scene but its invisible to the camera and reflections:

(to deal with noise read: How to avoid noisy renders in Cycles? and blender guru's article on how to reduce fireflies)


Novice - How cut littles holes symmetrically on a cube

you could use a displacement map, maybe you could get away with using a normal map, depends a little on where you want to use that mattress (in a game or in an offline rendering)

or maybe, if you are crazy, you could even sculpt it, make yourself a brush tip in that shape.


my fingers are bending weirdly, what did I do wrong?

Problem
The bones on the pinky and the ring finger appear to be rolled slightly. This can be caused by excessively rotating or grabbing the bones in those fingers. Because some widgets rely on the local transformations of the bones (especially high-level widgets to control bone-synchronized movements like grabbing, walking, and bending), they can be easily affected by their roll.
To illustrate, I added a generic wolf metarig to an empty scene and generated its rig. The third bone in the tail will be used as an example of how bone rolling affects widgets.
Below is the tail of the metrig, with the third bone in the tail highlighted. No part of the rig was modified.

The generated rig still contains a natural bone structure in a wolf's tail after curling the tail by rotating the end widget.

Now, that third tail bone has been rolled by 190 degrees and highlighted in the next image. Nothing else was modified in the process.

After posing the generated rig, some of the tail widgets are out of tune with the rest of the body, causing the tail to become unnaturally distorted.

Solution
To fix this distortion in your model, I'd compare the roll values of the problematic bones in your metarig to those of the default human metarig. (While it is possible to directly edit the generated rig, I wouldn't suggest doing so because that rig is very complex and contains many hidden bones.) Copying the roll values from the default metarig to your modified metarig should correct the bending motion caused by the rig widget.
Once you are done editing the metarig, tab into object mode and press the "Generate Rig" button in the metarig's Armature settings. This will bring the changes from the metarig into the rig.

For reference, here's a list of each of the metarig's bones in the right ring finger and pinky with their corresponding default roll values:

hand.R: -127 degrees
palm.03.R: 148 degrees
f_ring.01.R: 115 degrees
f_ring.02.R: 109 degrees
f_ring.03.R: 95 degrees
palm.03.R: 144 degrees
f_pinky.01.R: 113 degrees
f_pinky.02.R: 109 degrees
f_pinky.03.R: 101 degrees


This happens, if

you change a model that was already unwrapped by adding geometry.
you join separate objects into one mesh while not all of them were unwrapped.
you join separate uv-unwrapped objects into one mesh, without adding seams between them.

It might also happen, if you join two separate uv-unwrapped objects with unapplied scales.


I'd do it in the material via a normal map / bump map.


Can't convert the Ruler/Protractor into any Geometry type

This isn't a bug. Once drawn ruler gets saved into a Grease Pencil layer specifically created for it. However this layer will be hidden so that's why it seems that ruler disappears. With it visible converting a ruler into geometry is the same as for converting GP strokes into curves.

After hitting Enter to store the ruler, open Properties shelf with N, scroll it to the Grease Pencil layers rollout and enable visibility for the layer with the ruler/-s (it should be called something like "RulerData3D"). Make sure to select the layer itself. Then options in the Toolshelf > Grease Pencil > Convert to Geometry will become active.

Note that as Store ruler is used after drawning it to pass it to Grease Pencil and then - to geometry, if you press Ruler/Protractor to draw another one, the one you drew before will be still there (it is saved as ruler regardless).


Can i run blender as on a server as a binary source code?

You can use blender with no GUI, directly from a terminal or command line. As long as you can access the remote server (via ssh or remote desktop) you can issue commands to control blender.

The most basic command is

blender -b file.blend

-b will let Render in the background (without UI).

For a detailed list of other options read.

https://docs.blender.org/manual/en/latest/render/workflows/command_line.html

https://docs.blender.org/manual/en/latest/advanced/command_line/arguments.html


TypeError: 'Scene' object is not iterable

You are searching for ID properties of the scene objects ie scene[idprop]

The list of all custom properties names of the scene will be in  scene.keys()

The keys() method of a blender object returns a list of all custom property names.

for key in scene.keys():
    if key.startswith("list"):
        print("scene['%s'] = " % key, scene[key].to_list())

Similarly the items() method returns a list of key value pairs

for key, val in scene.items():
    if key.startswith("list"):
        print("scene['%s'] = " % key, val.to_list())

also lets say we want "list_2" but don't know if it exists, if it doesn't scne["list_2"] will throw a key error, in this case recommend using get

list2 = scene.get("list_2")
if list2 is not None:
    print(list2.to_list())
else:
    print("no list named list_2 in scene")

or list2_exists =  "list_2" in scene.keys() could be used.


How to use Boolean Operations to create Windows in a Mesh?

I was having this problem yesterday.
When you do booleans with a lot of round surfaces you can get these problems.
Check that your normals are facing the right way. Try to line up vertices through rotation or extra subdivisions and then re-mesh afterwards. Also make sure to remove double vertices.
It's also nice to have a linked duplicate, of the cut out, off to the side to modify.

As for a fix, Try this:


Is there a way to Live Project From View

If you are sliding vertices, or making loop cuts, make sure that the Correct UV option is enabled.

As an alternative you can use the UV project modifier, and use the camera as projector. That way the texture of the object will not change regardless of the geometry and the shape of the UVs. Once you are done editing the geometry you can make the projection permanent by applying the modifier.

The camera angle can be matched using the BLAM add-on. For more information see this post: How can I recreate the floor using a photograph?


Simple question, how to smoothout faces?

To make an object smooth, you either go to the left panel>Tools>Edit>Smooth or press space and type "shade smooth".

Then if you want to make the top faces flat shaded, use auto smooth or Edge slplit modifier, but they are essentially the same so one should only use one of them not both.


Changing Spline Evaluation Rate in Animation Nodes

You can evaluate the time at some interpolation whose derivative represents the velocity of the animation. In your case, such interpolation would look like:

Also, don't keyframe your nodes, try to use the Time Info and Animate Float nodes instead. Finally, you don't need the Mesh Info node, the same output is in the Mesh Object Info node.


So let say you've parented your mesh to the armature, With Automatic Weight for example, and that you've created a new bone called arm_L.

Select the part of the mesh that this bone is supposed to affect, go in the Properties panel > Object Data > Vertex Groups, create a new group called arm_L and click on the Assign button to assign these vertices to this group. If the group has the exact same name as the bone, the bone will automatically influence this vertex group.

Note that on the right of the vertex groups list you have additional functions.

Another method is the Weight Painting, you can't always count on it though.


Is there a way to shrink particles to mesh surface?

Sardi Pax released a tutorial for applying metaball particles as raindrops to glass, I believe there is no reason that prevents his method from being applied to a curved surface.
If this method is used instead of sculpted particles, they should conform to a non planar surface.
http://www.youtube.com/watch?v=RDte-IzvHlg


Splitting up a Texture and Object into different parts

Separating Texture Maps

You can bake textures from one object to another. If the objects are already separated (as it seems to be in your case) it makes things easier.

1. Separating the Object to which you want to bake the new texture.

Tab into Edit Mode and select all faces of the mesh you want to have in a separate object.
hit Shift+D to duplicate the selection.
hit P and select "Selection" to create a new object from your selected faces.

2. Preparing new Objct

Select your newly created object, (tab into object mode, if otherwise) go to "Properties - Materials" and delete the material.

With you newly created object, tab into Edit Mode and create a new texture of the size you desire (also pack the islands and correct the margins, if you want)*.

3. Bake texture from Original to new Object

Select the original object.
Shift>+Select the new Object.
Go to "Properties - Render - Bake", select "Textures", turn on "Selected to Active" and hit "Bake".
Don't forget to save the new texture map after baking.

Create a new material for your newly created object and assign the Texture(s) to it. You can then go to the original object and delete the part from which we created the copy in Step 1.

*Be aware, that changing the UV size as well as the size of the new texture might result in visible texture differences between the original and the new object.


What is the difference between a path and a bezier?

There are 2 main category:

Bezier
Nurbs

They differ in calculations.

Each is a preset for its category:

Bezier: It is a normal bezier curve with 2 splines,it is usually what you start with,It uses aligned handle.
Circle: It is a preset of Bezier that form a circle,It uses automatic handle type.
NurbsCurve: Nurbs are different in calculations,you can read the different here.
NurbsCircle: A circle formed by nurbs and is cyclic,made out of 8 control points.
Path: Is a very simple Nurbs,It can be used to create motion paths for objects when doing animations,It is very fast to edit.


Hi everybody, I'm not seeing the X,Y and Z selection in the upper left of the edit window when using the Spin tool

I suspect that the tutorial you saw was created on a beta version of 2.80 before around March this year. Later betas and the release version (2.80.75) moved those settings to the right-hand properties sidebar. Press the N key then the vertical 'Tools' tab on the edge of the window to show the settings indicated in the image below.


Origin point moves every time I try to select an object

I am pretty sure you're using the Cursor tool (red) instead of the Select Box tool (green). Switch to that one and let me know if everything works.

Note that the 3D cursor and the Origin of an object are different things.
The 3D cursor determines the point in which objects are created in the 3D environment. Read:
https://docs.blender.org/manual/en/latest/editors/3dview/3d_cursor.html?highlight=cursor
The Origin of an object is the pivot point where the object rotates.
Read: https://docs.blender.org/manual/en/latest/scene_layout/object/origin.html?highlight=origin


Split large mesh into small pieces efficiently using Python

This can be done by separating the big mesh into small meshes using the below script:

import bpy
ob = bpy.data.objects['MyMesh'] #### replace MyMesh with the name of your Mesh object
bpy.ops.object.select_all(action='DESELECT')
ob.select = True
bpy.context.scene.objects.active = ob
bpy.ops.mesh.separate(type='LOOSE')

UPDATE

If the object has no loose parts and you know the list of faces to separate then you can loop on them then separate using selection using the script below which I tested and it is working:

import bpy
ob = bpy.data.objects['MyMesh'] #### replace MyMesh with the name of your Mesh object
bpy.ops.object.select_all(action='DESELECT')
ob.select = True
bpy.context.scene.objects.active = ob
bpy.ops.object.mode_set(mode='EDIT')
bpy.ops.mesh.select_all(action='DESELECT')
faces_to_separate = [0,2,4,6,8,10] #### add the list of faces you want to separate
mesh = ob.data
bpy.ops.object.mode_set(mode='OBJECT')
for face in mesh.polygons:
    if face.index in faces_to_separate:
        face.select = True
bpy.ops.object.mode_set(mode='EDIT')
bpy.ops.mesh.separate(type='SELECTED')
bpy.ops.object.mode_set(mode='OBJECT')


How to enable double sided normals or double sided faces for rendering in python API?

You can set Mesh.show_double_sided flag to True for all mesh objects:

import bpy

for obj in bpy.data.objects:
    if obj.type == 'MESH':
        obj.data.show_double_sided = True

Alternatively you can iterate through the mesh data blocks and set the flag:

import bpy

for mesh in bpy.data.meshes:
    mesh.show_double_sided = True


2.9 render Animation Rendering only some of the animation

Welp. I'm an idiot.... turns out I was loading blender 2.8 and when the file was last saved working in 2.9. My render is working normally now in 2.9


You should move your Array Modifier above your Curve Modifier, however, you also have the wrong option selected in the Array Modifier.

Your Array Modifier is set to "Object Offset" to calculate the array copies. As the curve and your array object share an origin, this makes no sense.

You need to untick "Object Offset" and tick "Relative offset" instead.

Then you can either manually set the number of array objects that you need or change "Fit Type" to fit to the length of the curve (a new box will appear allowing you to select your curve).


Okay, so the issue is with your deform bones, particularly the facial deform bones. If you wanted to use them, you could re-align them, but since you do not, it is easier to just go ahead and delete them and then re-parent the armature. Here's how:

STEP 1

Select your armature and then under the Armature Properties panel, switch to Rest Position. Secondly, switch your active Armature Layer to be only the 3rd from the bottom most left. (See picture below, circled in red).

STEP 2

With the armature selected and only the deform layer active, tab into edit mode. Now you can delete all the bones you do not need. For this example, I selected the three head bones you probably will want (see selected bones in the photo below). Then I hid them (hotkey H) so that I would not accidentally delete those ones that I need. After they were hidden, I selected all the face deform bones and deleted them.

NOTE: The selected bones in this photo are the ones you should NOT delete. You can delete the rest of the face bones for your purpose (the ones around the eyes, ears, and jaw)

STEP 3

After having deleted the bones you do not want. Go back to object mode and select your mesh. Then go to the Object Data property tab and under Vertex Groups, click the arrow button and select "Delete All Groups". Don't worry, one more step and we're almost done!

STEP 4

Now, with your mesh selected in object mode, select your armature so that it is the active object (orange outline instead of yellow). Then parent (control + P) the mesh to the armature using Automatic Weights. Go back to Pose Position and check out your animation. It might need some tweaking, but you will not have any facial issues when exporting down the road.

EDIT: I deleted some posts because I did not realize the format was to keep editing my first answer. I apologize, but wanted to post a comment that got deleted in the clean-up about the OP's FPX export settings.
@Alberto Elorduy: By the way, my main fbx export settings are Selected only, Armature, Mesh, and empty. In armature only export deform bones, don't apply modifiers, and smoothing to faces. In animation I choose baked animation, key all bones and force start/end.


How can I switch from Single Image to Image Sequence in Compositor network, with a script?

Switching from still to sequence is actually part of the image data not the node itself. After you load the image used by the node you can set it's source to 'SEQUENECE'

image_node.image.source = 'SEQUENCE'


Blender cycles glow on transparent background

You should do this kind of things in the compositor node.
Replace the background plane's material with a holdout node.

Then, setup your compositing like this:

You can animate the size value to change the amount of glow in the rendering. Keep in mind that you will need to adjust the size of you image to not cut of the glow at the edges. Also try out different blur algorithms, the Gaussian doesn't work that well in this use case (personally, I liked Quadratic)

EDIT

If you want to hat the blur another color, put in the Alpha pass instead of the Image pass into the Blur node. Using a color node in between, you can have the glare every color:

EDIT 2

Sorry, I forgot the transparent background:

The input for the alpha needs to be a white blurred image, so iIf you are using a colored glare, put the color node behind the blue or duplicate the blur node and keep both synchronized. The max node is needed to make sure that the sign will always be fully opaque since the blurring is done into both directions: outside and inside of the image.

EDIT 3

If you want to restrict the effect to specific areas, create a black/white mask and color multiply if with the output of the blur node. In your case, the inside/outside is defined by the alpha pass of the rendering.

Now, the center of your image will be without glow effect. To have actual transparency in the image, you probably will need to add another mask to the alpha output but that shouldn't be a problem anymore.


Select object in Edit mode, press Ctrl + F > Tris to Quads, and set the Max Face Angle and Max Shape Angle to 179 in the tool options.

Go to Object Data Properties > Geometry Data and click Clear Custom Split Normal Data

And finally, In the same tab, under Normals drop down menu, click Auto Smooth

That should take care of it, hope this helps


Creating or Altering a Modifier, specifically Boolean

Well, the boolean modifier is not what you expect, maybe.

LITTLE INTRODUCTION TO BOOLEAN

What you do is choosing the object to use the modifier on, you choose the object to use to do the modifications, and then you select "intersect", "union" or "difference". At a programming level, the three options do the following:

-Intersect checks if each point of object A is "inside" object B, if not erases it. So you'll end up with just a portion of object A.
-Difference basically does the opposite: checks each point (to make it easy, since it's really messier than that, just imagine three nested "for" loops, one for each dimension, scanning each single point which makes the object), if it's inside the other object it deletes it.
-Union, instead, adds to the object A every point of object B which isn't already contained in it. So that you will STILL have B, but A will become equivalent to A union B.

LET'S GET DOWN TO BUSINESS

So, what were you trying to do, using difference between a plane and a cylinder in order to get new vertexes? Sadly it doesn't work like that, since planes are "directional, they have an orientation, and it's such as if they included the whole space under them, so, by doing a difference (or an intersect) between a plane and another mesh you will just have one side of the mesh to disappear.

If I can give you some advice, learn to use properly the "bisect" function, it basically does, in my opinion, what we want the knife to do in 90% of cases.

Or; if you want to use a mesh to "cut through an object", boolean is the right choice (just use "difference"), but avoid using it with 2D objects like planes.


How could I have an object's Z axis align with the first derivative of is location F-Curve

If the goal is for an object to move along a curve (e.g. Bezier) with one of its axis aligned with the curve's first derivative, as suggested by @atomicbezierslinger, you can use a follow path constraint. For example, if we want the object's Z axis to be aligned with the curve's tangent:

Set Follow  Curve to true.
Set the Forward axis to Z
Set the Up axis to either X or Y (setting to Z will not work, and the object might not move at all).


Sequence editor split screen video output black

Is sequencer output option selected in the scene render properties panel?


camera animation with known distance between frames

I'd set the Scene units to Metric or Imperial (or metric, seriously). Then you would take your path length (ie. 50m) divided by the frames elapsed (ie. 100f) to get the camera velocity (ie. 50m/100f = 0.5m/f). Then you know that the camera travels 0.5m for every elapsed frame. Does that answer your question?


How to add skytexture to viewport background?

As of 2.73, you can do this by enabling World Background in 3D view > Properties panel (N) > Display:


Best way to get a list of modifiers in Python?

bpy.types.Modifier.bl_rna.properties['type'].enum_items contains a list of all modifier types.

To get a list of their Python identifiers you can do:

modifiers = []

for modifier in bpy.types.Modifier.bl_rna.properties['type'].enum_items:

    modifiers.append(modifier.identifier)

Or, more Pythonically:

modifiers = [modifier.identifier for modifier in bpy.types.Modifier.bl_rna.properties['type'].enum_items]


Vertical Line Artifacts in Blender Cycles 2.83

Figured it out, kinda stupid. Just had to update my graphics drivers.


I would recommend that before you learn to use the blender game engine, you learn to use the normal blender engine so you can get the hang of the basics and it hugely minimizes some of avoidable mistakes - and if my experience was anything to go by, you'll make a ton.

I would recommend that you mess around with it, try to set yourself basic project and you'll slowly learn how to do new things and old things more efficiently.

Here are a few websites I would recommend:

https://www.youtube.com/user/CGAstym
https://www.youtube.com/user/GlebAlexandrov
http://www.tutorialsforblender3d.com/Game_Engine/Tutorials_index.html
https://www.youtube.com/playlist?list=PL9057AB8E3C66AE80 and archived


How to get the image textures around for eyes, eyelashes, and eyebrows when exporting a human model from MakeHuman

I had the same problem for a while but solved all 3... I hope the following helps you...

as you can see this is the end result...

The first thing to do is to select each object and make sure the UV's are aligned correctly...

To do this, split the 3D view (I assume you know how to do this) and change the new panel into a UV/image editor, then, select the eyes and with your mouse cursor over the 3D view port, tab into edit mode and press "A" to select all verts...

If you don't see them appear in the UV window then you need to unwrap them (You can find the Unwrap command in the tool shelf of the 3D view port).

I tend to unwrap them anyway just to make sure blender registers the UV maps.

If you do this then I found you will need to re-align the UV's manually so keep that in mind.

You should see them appear in the UV/image editor.

Once you have them aligned go to the UV/image editor panel, look at the bottom edge, just passed the menu options you should see a place to load or link an image.

Click the small page with an image icon to link existing images or load the image texture from wherever it is saved on the disk.

It should already be aligned. Tab out of edit mode and you should be done with the eyes.

Do the same for the eyelashes and eyebrows.

Okay so that's step one out of the way, onto step two...

the same nodes work for all 3 Objects(eyes, brows and lashes), they are as follows;

All you need to do is change the textures it uses for each one...

Please vote this up if it helped because it would lift some of the restrictions I have, so I can help others out...

Thank you everyone!

P.S. I have only got this to work with cycles renderer, as of yet I have not got this working with the Blender render engine but am determined and am working hard at it!


Dyntopo could be found in the "Active Tool" tab


Circular / Shape indentation onto curved surface?

I'm no expert in this field but I've used the "Knife Project" for this sort of thing as distinct from "Knife".  i.e. call upon the "Mesh-->Faces-->Intersect" then the knife project function to cut a hole in the bottle and in the shape of the intersecting object which would be in this case a cylinder.

You might be having the trouble I did and not using the Ortho view to make sure you're looking dead straight onto the bottle when you cut the hole.  The safe way to view exactly perpendicular to the bottle is to use the numpad's Home, END and PgeDn keys to set your viewpoint.  If you're just a fraction out, your hole won't be shaped or aligned correctly.

It's also essential that the bottle be aligned exactly with the X/Y axis so your hole goes through in perpendicular fashion.  You can set this in the bottle's Properties panel at right.  Open it's Transformation tab and see that it's Z "Rotation" axis is set to exact multiples of 90 degree segments.  i.e. 90, 180, 270 or 0 degrees, no fractions.  These figures can be typed in to get exact alignments.

The X/Y rotation numbers should be at zero, and if not, then in multiple of 90 degrees.

Once a hole is there, extrude it's vertices to the depth you want into the bottle, then close the inside base of that hole up and texture that surface with the label itself.

(Save each attempt in progressive Blender files so you can come back and redo if necessary)

I've only just started using the "Boolean" function and found that a relatively easier method of cutting an intersecting hole than the knife project, so you might like to try this first.

As for the Cherry bottle, you'd have to fashion an object to the shape of it's label first then extrude it so you've got a sort of 'drill' or punch, and proceed as with the circular label.

If you still can't manage a circular hole, get back to us here with a comment.  It's simple enough but you have to stick to some rules.

PS: is it essential to indent the labels?  You can't just "Paste" them on?


Instead of doing a loop cut you can use the Knife tool.

Press K to start the knife tool.
Optional step: If you need to cut 'through' the mesh (so the cut goes all the way around) press Z to toggle the Cut through option on.
Click once above the mesh and once below to create a cut across the mesh:

Press Enter to confirm the cut.


What does {'INTERFACE'} mean when returned from `invoke`, `modal` or `execute`?

The 'INTERFACE' operator return value is used to indicate where an operator has successfully completed by opening a menu or other UI component.

The comment in the source code for the operator return types states that it is:

/* "used for operators that act indirectly (eg. popup menu)" */
/* "note: this isn't great design (using operators to trigger UI) avoid where possible." */

  Source: source/blender/makesdna/DNA_windowmanager_types.h

This new return type was added during Commit - Fix T41041: "'Delete keyframe' removes markers too"

Reason for commit update was:

  "Operators that trigger UI events (but nothing else)
  were using 'CANCELLED' making it impossible to tell if an invoke
  function failed, or opened a menu."


You can Tab into Edit mode on the plane and use the Knife tool to trace the part of the plane that you want removed. Press K to activate the knife tool and left click to create points, to close a shape, simply left click on the starting point. You can also use right click to cancel a cut if you make a mistake.

Confirm the cut with Enter and there should be a hole in the plane.


Blender 2.78 release doesn't start in ubuntu 14.04

You don't need to use apt-get at all! Just download the zip from blender.org, extract it somewhere, then run the blender executable you will find inside the folder. That's what I did and it worked from the first time!


How can I assign a key frame to the bevel effect

Yes, you can. You only need to set the key frame from the Bevel field by hovering your mouse over it and hitting I.

You need to use the Bevel modifier and not use ctrl+B in Edit mode. You can find it the right side of your screen, on the Properties panel, if you click on Modifiers (the little wrench icon) the list of available modifiers will appear and you just need to click on Bevel to call the Bevel window, then you hover over the Width field and press I to generate a key frame.

Do that at the beginning of the animation, to set the starting point, then change the value on the Bevel Width field to what you want to have at the end of the animation, make sure you are at the end frame as well and hit I again while your mouse is hovering over the Bevel field.


Use the mouse actuator on your camera.

delay>and>Mouse, mouse look.

Set the delay to 0.01 and enable true-level-triggering this will behave as an always sensor, but delay works better with mouse look. The delay will read 0 but it really will work for 0.01 frames.
Create a mouse actuator and set the type to mouse look.
You can specify how you want the mouse to look in the properties of the actuator. Basically, if it's turning too far when you move your mouse, increase the min. value and decrease the max. value.


Here is a proposal for the first question, without using the matrix conversion (not sure why it's necessary there?). Does it work for you?

import bpy
from bpy.props import FloatProperty
from mathutils import Vector, Matrix, Quaternion, Euler
from math import degrees, radians

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

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

        obj = context.object

        row = layout.row()
        row.label(text="Active object is: " + obj.name)
        row = layout.row()
        row.prop(obj, "name")

        row = layout.row()
        row.prop(obj, "rotate_x")
        row.prop(obj, "rotate_y")
        row.prop(obj, "rotate_z")

def get_rotation_z(self):
    return self.rotation_euler[2]

def get_rotation_x(self):
    return self.rotation_euler[0]

def get_rotation_y(self):
    return self.rotation_euler[1]

def set_rotation_z(self, value):
    self.rotation_euler[2] = value

def set_rotation_y(self, value):
    self.rotation_euler[1] = value

def set_rotation_x(self, value):
    self.rotation_euler[0] = value

def register():
    bpy.types.Object.rotate_x = FloatProperty(name="Rotation X",
            description="Rotate object.",
            get=get_rotation_x,
            set=set_rotation_x,
            unit='ROTATION')
    bpy.types.Object.rotate_y = FloatProperty(name="Rotation Y",
            description="Rotate object.",
            get=get_rotation_y,
            set=set_rotation_y,
            unit='ROTATION')

    bpy.types.Object.rotate_z = FloatProperty(name="Rotation Z",
            description="Rotate object.",
            get=get_rotation_z,
            set=set_rotation_z,
            unit='ROTATION')

    bpy.utils.register_class(HelloWorldPanel)

def unregister():
    del bpy.types.Object.rotate
    bpy.utils.unregister_class(HelloWorldPanel)

if __name__ == "__main__":
    register()


Seems like a basic question but I'll give it a go.

Is the classroom one big object? In the top-right corner, there is a hierarchy. It currently reads "Lamp, Lamp001, Lamp006..." Is the geometry in this scene represented by one entry? If not, go to the next paragraph. If so, it should first be split into multiple objects. Each desk, table, etc. should be its own object. To split up the mesh one object at a time: select the faces belonging to an object, press p (no ctrl or shift) to bring up the separate menu, then choose "selection." It should now be its own object. You will have to repeat this for every individual object.

Some objects will need multiple textures. For example, a desk might have a plastic back but metal legs. To do this, go to edit mode and look at the materials tab. There should be an "assign" button. Clicking it will assign the currently selected material in the materials tab (there can be multiple, click the plus sign on the side to add another) to all selected faces in the viewport or 3d view. This way, an object can have multiple materials each with its own texture.


I'm no expert, but I'll see if I can help quickly.  Is the outer mesh with normals pointed in the right idea?  You might need to give it some thickness somehow, perhaps by using a solidify modifier on its surfaces.  Or maybe the whole thing is trying to behave as a solid (even though you say the normals face inwards) ...if the tutorial got you here, then that sounds wrong.  But just because it is being displayed as a wireframe doesn't mean it isn't a solid.  (I don't think; I've been away from blender for a minute)


How to get the normal of the face which was hit in a collision?

You could try to use a ray sensor:

c = bge.logic.getCurrentController()
ray = c.sensors["raySensorName"]

if ray.positive:
    pos_vec = Vector(ray.hitPosition)
    normal_vec = Vector(ray.hitNormal)


Blender 2.8 and Caustics in YafaRay and POV

LuxCoreRender is able to use bidirectional path tracing with CPU rendering that is more suitable to render caustics. It is also free and open source and its integration to Blender is alright. It is worth having a look.

It takes a long time, but it works. You need to select Bidir engine and Metropolis sampling seems to work best:


Copy and Paste creates random null objects from existing geometry

If you want to duplicate objects in your scene, instead of using Ctrl-C to copy them, consider using Shift-D instead. Admitedly. It's a bit confusing that there are both methods available when they don't seem to completely work the same way. I don't use Ctrl-C for anything except copying poses in Pose Mode. And I have no issues. Interestingly, when I just tried to use Ctrl-C on an object in a scene, as you have done, I got a weird result also: It made an extra copy of my armature object. However, it's an armature that wasn't even part of the object I tried to copy. Very odd.


How to render Compositing only by OpenGL?

That just not possible. OpenGL rendering only "saves" the current viewport content as an image. But when the only content created is in the Node Composit, that won't serve as a valid viewport content. Though there is a File Output Node for your Node Tree that you might use instead.


How to deform the outer part of a torus along one axis?

You can use the Proportional Editing mode :

Select only the outer ring of vertices
Activate the PET with O or with the button (blue arrow in the screenshot)
initiate the scale on the desired axis THEN control the radius of the PET with your mouse wheel

You can try different fallof profiles (the "curve" button right to the PET). "Sphere" seems a good choice.


Making a spherical gradient that becomes transparent towards the outside

As Rob suggests you can use a Gradient node in Quadratic Sphere mode:


You might want to try changing the Ray Visibility settings instead.  (Although turning up the maximum bounces might be better in cases where you need these settings turned on)
The two settings that I turn off to help me get rid of these artifacts are Glossy and Transmission.

You would find these settings under Your light source > Object > Cycles Settings.
With both settings on:

With transmission off:

With both transmission and glossy off:

Hopefully this helps you! :D


Grease Pencil: customize the eraser as of in the old versions

The soft eraser now has two new parameters:

Affect Stroke Strength and Affect Stroke Thickness. These parameters define how the eraser affect the opacity and the thickness. The old eraser only affected the thickness, and the new default parameters affect the opacity (strength) in a 100% and the thickness in a 10%, so the stroke gets less and less opacity and the thickness is reduced in a small proportion (10%). We set this values after a lot of test to get the feeling of erasing in a paper.

If you want back to the "old" soft eraser, just set the Stroke Strength to 0% and the Stroke Thickness to 100%.

With these parameters you can configure the "feeling" of the eraser.


Good alternatives for middle mouse pan button?

You can use "Emulate 3 button mouse" option.

Use Alt + LMB to pan.

Use ShiftAlt + LMB to move.

This option is in the input part in the preferences and is generally used for touchpads.

In 2.79:

In 2.8:

This option has a little incidence. As Alt is dedicated to that, even outside of the 3D View (in panels), you can not use it for some other operations, like Alt+Clicking a button (which in some case allows to set a value for multiple objects).


Disable Smooth Stroke in the Stroke section.

In Blender 2.8x this has been renamed to Stabilize Stroke.


I'm sure you figured it out by now, but it took me a while to find the right answer...so for anyone else: I used the Principled volume node
At first it is also dark, but take a look at the Emission Strength and Color Parameters...the dark fogs shall lighten up for you!
Have fun!


Thanks to zeffi's comment i was able to figure out a better way that decimate modifier, with almost none shape changes.
1)select mesh
2) go to edit mode
3) select all vertice
4)press delete and click limited dissolve
this will maintain the geometry but will get rid of non used vectice


Is there any way to have a projection without size changing?

I think you need to switch your camera lens to Orthographic:

You can get the same effect for your 3D view (not a camera) by pressing 5 on Numpad.


Modeling a curved ring projected to a circular top

Your blueprint is not very clear but I've tried something, here it is, step by step, tell me if it's correct.


I've used a topology similar to yours and it seems to work fine with almost no artifacts. I just used and applied a Shrinkwrap modifier with a cylinder of the same radius as Target in order to correct the topology a bit and make it stick to a nice cylinder shape:


How do I construct a transformation matrix from 3 vertices?

The following python code from orientation-matrix.py illustrates how to convert 3 coordinates into a transformation matrix:

import bpy
from mathutils import *

def make_matrix(v1, v2, v3):
    a = v2-v1
    b = v3-v1

    c = a.cross(b)
    if c.magnitude>0:
        c = c.normalized()
    else:
        raise BaseException("A B C are colinear")

    b2 = c.cross(a).normalized()
    a2 = a.normalized()
    m = Matrix([a2, b2, c]).transposed()
    s = a.magnitude
    m = Matrix.Translation(v1) * Matrix.Scale(s,4) * m.to_4x4()

    return m

#

obj = bpy.context.active_object
obj.matrix_world = make_matrix(Vector([1,1,1]), Vector([1,2.5,1]), Vector([0.5,1,1.5]) )

The Matrix.Scale is just thrown in for completeness and you can leave it out if you are content with scale=1.  The order of the matrices in that multiplication is pretty important (I did not get it perfect on the first try).


1. Do you have any procedural textures (nodes)?
If so, bake them to image textures. Lot's of stuff about baking on YouTube.
2. What is your aim with exporting it?
Is there some way of importing those textures into where ever you want the model?
If so, the UV's should be there whether or not the textures are.
3. Are there any other formats that you could use?
4. Relative paths?
Have you tried moving your textures into the same folder as your blender file, but not packing it all into the blend file?
5. And of course restarting Blender.


A few options:

Using the compositor, changing the materials for the emissions shader, or harnessing the power of color magangement.

Each one will have a different effect, and can also be combined according to your artistic intentions.

Option 1: Using the compositor you want change the color for the flame so it doesn't look white.

(click on any of the images to enlarge)

To isolate the flame from the rest of the image you can enable the emissions pass on the render layers.

On the compositor you can see that you have a new image that contains only the emissions of the image.

You can then use this information to tint the image, so that only the flame is affected.

Plug the Emit information to a vector normalize node (to bring the values to a scale form 0 to 1), and plug the result to a color mix node's factor. That will allow you set the color you want the flame to be. Ony the flame will be affected by the color selected on the Mix node.

Note that the edges are a bit rough since the emissions pass is not antialiased, so you can add a Dilate/Erode node in Feather node to make the edges smoother:

Adding a blur filter to the emissions pass will allow you to create some glow...

Here's the blend file if you want to download it:

Now in my opinion that still looks like a colored light bulb instead of a flame, so we can try now

Option 2. Using more than one emitter shader for the flame.

The flame material for a candle is hardly ever just a single color emitter.

Here is a different example file to play with:

You can start with a node setup like this for the material of the flame:

(Click on the image to enlarge)

It can be broken in 3 main components:

First, a gradient for the different temperatures of the flame.
A first emitter that is mixed with some transparency. This is the one that will determine how the flame will look in terms of color, brightness and transparency.

The biggest issue is that with just one emitter is that if you make the flame brighter to illuminate surrounding objects it just becomes white, so you need to add

a second emitter that is unseen by the camera, but that illuminates everything else (The light path node prevents the second emitter to be seeing by the camera).

If you look at this example, this second emitter is 100 times brighter than the flame.

Then you can add more effects on the compositor:

Option 3: Using Tone Mapping in the compositor

With a single emission shader, using a gradient to create a more realistic flame.

Again, in order to see the color on the flame, the emission strength would need to be low, but that makes the surroundings very dark.

Bringing up the emission's strength will make the scene look brighter but the flame's gradient is way to bright now, past the 100% clipping point

Looking at the waveform monitor we can see that the flame is way over the 100% mark, so all detail and color is gone, no more information can be displayed on white.

Using a Tonemap node we can try to modify the dynamic range of the scene by remapping of the values to fit on a scale of 0(black) to 1(white):

The colors for the flame are back, but the image looks very washed out and boring because it has a much lower contrast and less color saturation. To fix that we can alter the image values with a color curve.

Lastly just add a glare node:

Option 4 Using color management (as suggested by this answer)

Using a custom 3dLUT (Look Up Table) for the device transform you can use a much wider dynamic range on the scene.

Again, with a single emitter shader on the flame, a LUT used on the color management will allow us to use luminance values much brighter than 1 and re-map them to fit a range between 0 and 1.

For more information read this post.

User @troy_s has created a set of LUTs and OCIO config that greatly enhances blender's cycles rendering and its ability to deal with a wider dynamic range, thus creating more photorealistic results. They can be downloaded here, along with the instructions on how to install and use.


Don't waste your time, your card is too old, it is not supported by blender. As stated in the link

Enabling GPU rendering for Cycles?

  Cycles only supports CUDA GPUs with a CUDA compute ability of 2.0 or higher. To use CUDA, check to make sure your GPU is on this list of CUDA capable GPUs and has a ranking of at least 2.0.

Your's doesn't meet that criteria.
You can see the compute capability of CUDA cards here: https://en.wikipedia.org/wiki/CUDA


How can I pull two objects together without scaling them

In the 3D View header, open the Options overlay and toggle Locations on


Insert Keyframe will only create keyframes for the selected bone(s), not for all the bones of your armature. You've only selected one bone in your video, the mirrored bone will also move because of the X mirror option, but it won't be taken into account as it is not selected.
All Channels means that it will create keyframes for all the channels of this bone (Location, Rotation and Scale).
If you want the rotation to be taken account for all your bones, activate the Auto Keying option, but in that case you don't need to insert a keyframe.
Also, try to not report a bug if you're not sure it's a bug.


How to fake reflective caustics in Cycles?

Cycles does render caustics. But since the light is traced from the camera to the lights the probability that caustics are rendered is very low.
When they are rendered most people call them fireflies or noise.

That's why the Filter Glossy in the Caustics tab is set to 1 most of the time.
When you set it to a low value (or even zero) you will see the noisy caustics.

To fix the noise you now have the option to:

Use an extreme high number of samples
Turn up Filter Glossy
Turn on denoising in the Layers context

So Cycles is capable of rendering caustics but they will always be very noisy.

Edit: the example above is rendered with 10000 samples, 0.5 Filter Glossy and 2px denoising.

Edit 2: It also can help to set the clamping of the direct and indirect light. This will reduce the noise of caustics but also make them less bright.

This example uses a different IOR but you can see by setting clamping of the light fireflies are less visible.


How to activate ANOTHER object's actuator (Python)?

You do not do that. It is not supposed to "remote control" objects that way.

You can indeed connect logic bricks of different objects. But this quickly ends in a chaotic mess.

You can delete objects via endObject(). In difference to the actuator this does not need to be called by a controller of the object to be deleted.

Your sample could look like this:

import bge
scene = bge.logic.getCurrentScene()

for object in scene.objects:
    if object.name == "Critter":
        object.endObject()
        ...


CUDA problem Error: Invalid value in cuMemcpy2DUnaligned(&param)

Not an answer to your problem, but an assertion that I too have come across this phenomenon and a workaround:
I had this with a system of mine that has 2x Quadro K4000 GPUs. The culprit was a scene that does not fit into the GPU memory. As per a patch in Blender 2.80, there was an option added that would let Blender render such scenes by swapping memory in and out as needed. This works well on single GPU systems, but dual GPU systems have an issue with that. I'm not sure why. Up until recently (2.83 or so), the scene would render a few frames and then stop. With 2.92, it refuses to render on first attempt, throwing the above error.
My workaround was to disable any one of the GPUs, resulting in a render without the error. One of my GPUs (probably the one connected to my monitor) was rendering way slower than the other one. It's worth doing a test and using the faster of the two. While it's not an ideal solution, it might at least get your scene rendered.
Hope this helps!


Wacky, weird colors when entering sculpt mode (blender v2.83)

I had the same issue for hours in Blender 2.9
It appears everytime I apply boolean modifier on two or more objects or when I join them. My assumption is that it might be because of different face densities.
The solution from John Eason is working for me. Just turn off the Face Sets.


Can't get Graphics Chipset AMD Radeon R7 200 Series to work with GPU rendering

Oland is the name of the GPU. AMD cards show as the codename for the chipset.

Select it as your OpenCL device and then enable GPU compute for the scene.

Keep in mind that not all render features are available when using AMD cards.


You need to fix the armature bones to pivot in the center of the arm's ball joints:

Select the mesh and in Edit mode (Tab) select vertices such that the 3d gizmo (the center of selection) is in center of the ball joint:

Snap the 3D Cursor to the selection: Shift S > To Selected

Select the armature object and enter Edit mode, select corresponding joint and snap it to 3D Cursor with Shift S > Selection to Cursor

Do it for every joint. You can also set the bones Roll to align bones rotation axes - place the 3D Cursor to the direction you want the bone to be aligned and Ctrl N > Cursor:

Select the mesh, then shift-select the armature and parent it with Empty bone weights(Ctrl P > With Empty Groups). Now you should see a vertex group for every bone inside mesh data properties tab.

Assign every mesh piece to it's corresponding vertex group. You can select a connected component with Ctrl L:

You are ready to animate.


In 2.81
I needed to tick "Use Alpha" and was able to use transparency.


How to use index passes in other compositing packages?

To make it work in all other packages you need to manually create custom output channels and append the passes to your Multilayer EXR via Blenders Compositor:

In Nuke you can use J_Ops. With this tool you don't need the additional node setup above. There is a tool called J_GotSomeID which is able to detect such IDs from the EXR Multilayer automatically.

Select the pass (IndexOB or IndexMA)
Set the Selection Mode to Find
To detect the IDs click Autofill


Why is their weird noise in my render lighing and why does my lighitng still look off?

It could be the default shadow settings for Eevee.  Try setting the cube size higher in this menu.


This is a nice example of a very unclear question. I actually got it completely different than the other two, as I had a piece of cake in mind like this:

You'll need 36 verts for this to work, and have the disc filled with an n-gon. Then, connecting the vertices opposite each other using J would do the trick.


If your goal is to get a texture with those values then just bake the Normals but select World instead of Tangent in the menu.


Missing the texture paint mode stencil mask overlay when in texture paint mode for an object (blender 2.8)

You didn't pack the image. Anyway, I've created a new one. What you need is just to choose a brush with a higher Strength and another Blend mode. Also, be careful with your unwrapping, some faces are overlapping so when you paint on a part it will paint somewhere else. The easiest way, if you only paint in the 3D View, is to unwrap with Smart UV Project. If you also paint in the Image Editor, maybe mark seam and then choose the simple Unwrap mode.


The problem comes from the add-on "rain".
It needs to register each class in classes. Like this:
from bpy.utils import register_class
for cls in classes:
    register_class(cls)

and unregister like this:
from bpy.utils import unregister_class
for cls in classes:
    unregister_class(cls)


How to attach rigged cloth with a rigged character.?

Use a Child of constraint on the cloth armature to make it a Child of the body armature and a related bone. Then you can animate the strength of the constraint if you want to take it off. (Or use the addon for dynamic parents.)


Glass cup not pixelated, but a lot of noise, which caused by small amount of samples.

It can be reduced in viewport with OptiX viewport denoiser in Render tab (OptiX avaible only on RTX cards):

at render with  View layer denoising:

or after render with Intel Open Image Denoiser node in Compositor (Denoising Data should be checked in View Layer):

And the last, the scale of blender layouts could be customized by holding Ctrl + Middle mouse button pressed with moving mouse Up and Down


Consider inserting more keyframes so you have more options to change directions.  Perhaps you would need to calculate intermediate turning locations such as locations on a simplified half ellipse to avoid an obstacle.

frame_num += 30 would become

frame_num += 5 and other python changes
Consider a [Follow Path Constraint] whose offset and influence can be animated via keyframe.  Perhaps left and right turn constraints.


The zooming and rotation work a little oddly in Blender. Blender has to choose some point around which to rotate and toward which to zoom. If you're very far from this invisible point, zooming is exaggerated and fast. If you're very close to this invisible point, then rotation is very sensitive, but zooming gets slower. In fact, if you continue to zoom in, you'll eventually reach this invisible point and be unable to zoom any further.

The main problem is that it's hard to tell how Blender chooses this point, and when it gets updated, except that it tries to use whatever you've centered your view on. SO, select what you want to work on (an object, a collection of verts, whatever) and press Num.. This will zoom to and center your view on whatever you have selected. This also tells Blender to reset the point that it's chosen for your view center and zoom location. This should make Blender's rotation and zooming a bit more sensible, until you need to work somewhere else, in which case you'll have to do it again ;-) Anytime your zooming and rotation seem to be acting weird, just select what you're working on and use Num. to recenter your view on that, and it should return to normal. It seems like this might be bothersome, but I've found that I use Num. so often anyway, just to see what I'm working on that it ends up being pretty convenient.

BONUS: For these reasons, and others, I usually turn on "Rotate Around Selection," too.


How to make a texture that shines, or paint a material?

You UV unwrap and texture your mesh with a glossy map. The parts you paint white will be glossy, and the parts left black will be diffuse. Use that glossy map to factor a Mix Shader that has a Diffuse Shader and a Glossy Shader connected to it.

If your Glossy and Diffuse shaders are plugged in the opposite way then it will be inverted, with black values being glossy and white diffuse, so pay attention to how you've set up your mix node. Any areas that are grey will be neither fully glossy nor fully diffuse, but something in between.

Of course this concept can be applied to the factoring of any mix, whether it be glossy/diffuse, red/blue, bumpy/smooth, transparent/opaque... the possibilities are infinite.


how do i make a seven segment digit clock animation?

Some python code can do that for you:D

Create two text objects and name them 'hour' and 'minute' respectively
Run scripts below.
Scraping the Timeline and you now have a digit clock animation. (Choose a digital font if you like.)

scripts:
import bpy

def update(self):
    frame = bpy.context.scene.frame_current

    minute = bpy.data.objects['minute']
    hour = bpy.data.objects['hour']

    hour.data.body = str(int(frame/60) % 24) + ' :'
    minute.data.body = str(frame % 60)

def register():
    bpy.app.handlers.frame_change_post.append(update)

def unregister():
    bpy.app.handlers.frame_change_post.remove(update)

register()


I am totally lost in blender and cant find my models

You can always press Shift+C to reset your view ;)


How can I model from angeled photos in blender?

You can use blam (or fSpy) to match the camera with the a photo and model from there. See this link that outlines the way to do it: How can I recreate the floor using a photograph?

If you have access to a bus that is parked and you can do the photographs yourself it would be a lot easier. Just go around the bus making a lot of photos with the same lens, import the images into the video clip editor and then use motion tracking as an aid to re-construct the object.

Read: How to do photogrammetry within Blender?

You don't need a fancy camera. A phone will be good enough. If you are concerned about the distortion of the lens, Blender has tools to undistort the image.

Read: How to determine lens undistortion values for motion tracking?


Change custom Node input through Python console

The group node in the material has input sockets and you can set the default_value of each socket. The default_value is used when there is no link to the socket to get a value from another node.

mat = bpy.data.materials['Material']
gr_node = mat.node_tree.nodes['Group']

gr_node.inputs['Elevation'].default_value = 15.3


See background image through solid shading in edit mode

You must change the view from Back to Front. See the screen shot:

You can change to Opacity of the image, if it makes your mesh to hard to see using the slider.