text:
Camera in BGE seeing through non-transparent solids when having small near clipping distance
I have a group of legionary puppets fighting busily in Game Engine. They are mesh animated by armatures, and have equipment parented to empties parented to the armatures:
So they look like inthe orthographic embedded player.
However when they are looked at through the perspectivic camera (parented to another puppet's head), both in embedded and standalone player, they show a curious graphic issue:

The bodies of some of them is seen (or maybe actually is) in the front of their shields. What is the cause of this, and how I might try to resolve it?
EDIT: Further testing showed that when they are not moving and displaying the animations the issue nevertheless occurs, and that ortographic cameras avoid it.
EDIT2: The issue was finally found to be related to the absurdly small (0.00000001) 'camera near clipping distance', which I have set to see my own cheek-plate. It has nothing to do with offsets, levels of detail or parenting. But I still can not infer why this should cause such a problem.

Could it be you enabled "Alpha blend" on the materials?

@Monster I only see a changeable property named 'alpha blend', no checkbox. It is set to opaque, but changing it does not seem to help.

I asked because this can cause sorting issues when used extensively.

You above image looks like the shields got an offset (I can't tell where this could come from). Can you have a camera that orbits around your scene? It might show more details on the topic ( a demo blend would help too).

@Monster Thanks, really. But how can I attach a (blend) file? There does not seem to be an icon for this, only for images.

Have a look at this: https://blender.meta.stackexchange.com/questions/344/where-to-upload-blend-files-non-expiring-links

EDIT2: The issue was finally found to be related to the absurdly small
  (0.00000001) 'camera near clipping distance', which I have set to see
  my own cheek-plate. It has nothing to do with offsets, levels of
  detail or parenting.

You found the issue by yourself. I just want to answer the followup question:

why this should cause such a problem.

The 3D engine of the BGE uses Z-Buffer processing to "sort" the rendered pixels. This means your scene will be "sliced" between the near and far clipping distance of the camera.
Within one slice the render can't decide which face is in front of the other. So it will pick more or less a random one. That is the reason why you should avoid planes covering each other with a very small distance (e.g. a painting at a wall). This can cause Z-Fighting at pixel level.
In orthogonal mode you see the same detail level at all distances. Therefore the z-Buffer is equally distributed (all slices have the same thickness).

In perspective mode the object near to the camera are rendered with more visible details than objects more far away from the camera. The sliced near the near clipping plane are thinner while the slices near the far clipping plane are thicker.
As you setup a really close near clipping plane you get a really detailed helmet with the costs of the other characters end in very thick slices.
I assume the result was that the complete shield and the legs are within the same slice sometimes rendered in the wrong order. The slices are so wide that you can't see pixel-wide Z-Fighting (or it is not obvious in your sample images).
Solution
Obviously the near clipping plane should not be that close. When you set up a more practical value (e.g. the default value) you should avoid the z-fighting effect.
There are several different options to show the helmet.

use an overlay scene to render the helmet (best option)
move the faces of the helmet more far away that it is still in the camera frustum


text:
Firing missilein animation many times
I have some objects (lamps, meshes) parented to an empty. I want to fire them from a specific location as a missile. (make a copy of them there.) In bge, this is pretty simple with the 'Add Object' actuator, but I want to do it in animation. Is there a clever way, using animation nodes and/or direct python, or should I manually keyframe the missile to appear in the right frame, depart, appear in the next firing frame... I have tried 'instancer node', but it added all the copies at the frame, when it was first executed, add didn't copy the parented objects, just the empty.

to instance a full hierarchy of objects the easiest way is to group them, add as a dupligroup on some layer and use this object as the AN instancer object -need to activate 'copy full object'-
you can animate the number of instances, so new objects appear on new frames, or you can have all there at the first frame and animate them scaling from zero...
to add more animation the easiest way would be generate it from AN, something simple and parametric, or have some cyclic animation in the objects... if you need to sync it to start time for each object it can be done also, but it's more complex
here's a test scene (AN 1.6) with some simple objects, made 100 instances of a dupligroup, then use a loop and a couple of delay nodes to first scale them, and then animate in random directions, the trick is to use instance index as seed and delay factor -the usual procedure with loops-
https://dl.dropboxusercontent.com/u/16486113/Blender/archivos/temp/AN/AN%20cohetes.blend
https://dl.dropboxusercontent.com/u/16486113/Blender/archivos/temp/AN/AN%20cohetes.png

source: Stack Exchange

license: Creative Commons - Attribution Share-Alike - https://creativecommons.org/licenses/by-sa/3.0/

sort: votes


text:
Adding leafs to a tree not showing up correctly as they should
I'm making a forest pack and I've got everything down except for the leaves, the only problem is that I don't know how to get the leafs to the right scale and rotation so that they don't show up "wierd" and my goal is to make the leafs look like in the following image:

But currently my tree looks like this (the one on the left):

I want to know how I can make my tree (the one on the left in the second image) look the the other two trees, I am using the Sapling add-on in Blender 2.75.
Any help on how to get the leafs of the pine tree to look more professional and how they're supposed to will be greatly appreciated.
I am using a leaf texture from CG textures (now Textures.com).

all_licenses: Creative Commons - Attribution Share-Alike - https://creativecommons.org/licenses/by-sa/3.0/


text:
How do i get an array of objects with increasing rotations to stay on a specific axis?
quick question:
when i use an empty as an object offset in the array modifier and i rotate for example an array of cubes with it around the y-axis i get a circular arrangement like this:

is it possible to get the empty rotation on the objects themselves like this, so that the objects stay on the z-axis? the rotation has to increase with each new object (i.e. 10 / 20 / 30 degrees etc.)

thank you in advance!

I dont think you can do this with the array modifier or a different modifier. So I made this code:
import bpy
import math

Count = 10
distance  = [0, 2, 0]

rotationX = 10                              # in degrees
radiansX = rotationX *(math.pi / 180)       # in radians

rotationY = 0
radiansY = rotationY *(math.pi / 180)

rotationZ = 0
radiansZ = rotationZ *(math.pi / 180)

startRotationX = 0
startRotationY = 0
startRotationZ = 0

for x in range (0, Count - 1):
    bpy.ops.object.duplicate_move(OBJECT_OT_duplicate={"linked":False, "mode":'TRANSLATION'}, TRANSFORM_OT_translate={"value":(distance[0], distance[1], distance[2]), "constraint_axis":(False, False, False), "constraint_orientation":'GLOBAL', "mirror":False, "proportional":'DISABLED', "proportional_edit_falloff":'SMOOTH', "proportional_size":1, "snap":False, "snap_target":'CLOSEST', "snap_point":(0, 0, 0), "snap_align":False, "snap_normal":(0, 0, 0), "gpencil_strokes":False, "texture_space":False, "remove_on_cancel":False, "release_confirm":False})

    if x == 0:
        startRotationX = bpy.context.object.rotation_euler[0]
        startRotationY = bpy.context.object.rotation_euler[1]
        startRotationZ = bpy.context.object.rotation_euler[2]

    bpy.context.object.rotation_euler[0] = startRotationX + (radiansX * (x + 1))
    bpy.context.object.rotation_euler[1] = startRotationY + (radiansY * (x + 1))
    bpy.context.object.rotation_euler[2] = startRotationZ + (radiansZ * (x + 1))

I hope this works!

hey, first of all thanks for your afford! i have pasted your code in the console and the only thing i get is an array of 10. but there is no rotation at all. am i doing something wrong? i am using the console for the first time.

for me it is working. Maybe you need to paste it in the text editor?

I would recommend Drivers for this.
It really depends on what you are doing, but if turns into anything related to animation, this seems logical.
The disclaimer is that it won't work with the array modifier, however duplication via something like Ctrl+D also copies the driver so that part stays dynamic.
First steps are to create both a cube and an empty at the 0,0,0 origin.
To create the driver, 1st select the Cube Object, then turn on your properties panel N, and Right-Click on the X rotation field >> Then Add Single Driver.
Go to the Graph Editor Screen, and at the bottom menu change F-Curve to Drivers.
N to bring up the right side panel if it's not up already.
At the left side of the Graph Editor, be sure to select the X Euler Rotation Entry.
Scroll down to the bottom of the panel on your right and there should be a variable called var already, make sure that its type is set to distance, I believe that by default it gets set to Transform Channel.
Then set Ob/Bone 1: Empty
Then set Ob/Bone 2: Cube
Up above the variable list is an Expression field labeled Expr:, go ahead and set this field to the following:

var*((pi*0.5)*.1)/-2.00000

And hit enter.
You can now close the graph editor, and keyframe &/OR duplicate the cube around, and it will rotate respective to its distance from the Empty's location.


text:
How can i make a color transparent in node editor
I have these renderlayers:

In compositor I subtracted the second renderlayer from the first one (or used the difference node, since in this case they result to the same image)

But where the cube is, is now black (of course, since this is where the cube is, in both renderlayers). Is it possible to make transparent only where it's black on the image, so not object related, but just regarding the color of the pixel?

You can use the object index mask and the alpha over node to make the object transparent in the node editor.
Set object index:

Add the object index render pass:

Node setup:

Thank, but is it possible to make transparent only where it's black on the image, so not object related, but just regarding the color of the pixel?

Sure, behind the scenes the id mask node generates a black and white image, where the object is black and the rest if white. You can put any grayscale image into the alpha over node's factor input, and it will work in a similar fashion.

How do I enable IndexOB? Because after I set the object index mask, I don't see it

Right, forgot to mention that! edited the answer

Thanks, but what exactly object index and ID mask exactly do? Like can I also make brown colors transparent?

I tried explaining this several times in text, but eventually decided this is better: https://www.youtube.com/watch?v=-CcOBLmvJAs

Or actually... this is better: https://www.youtube.com/watch?v=yuafulRKybs


text:
Stack several time the same channel?
I have a complex animation movement so I parented my mesh to several empties that I animate separately.
EDIT : eg. a robot character, made of serval meshes; which are parented to :

a null who rotates on the Y axis (main move); which is parented to :
a "ticking" cycle on the Y axis; to break the "linearity" of the rotation with a stopmo-like movement.  The tick is only a few keys with a cycle modifier applied on the curve.

I personnaly think that it's more easy to "break" the animation steps.
I was wondering if, rather than doing this (can be a mess for complex animations), it was possible to stack several time the same channel (here, Y rotation) so I can combine those two movements while keeping my keys clean ?
If it is possible, how ?
Thanks !

I'm not sure what you are asking ('over-animate'?). Are you able to add more detail to your question?

Using drivers, you can use a channel as input value for almost everything you want to animate.
To keep it simple, I've used only two objects: the location X channel of the Sphere will be applied to the location X channel of the Cube

In this example, I've added drivers to the Cube location, (move the cursor over the location fields then press d)
In the Graph Editor, switch to Drivers Mode

Select the channel you want to animate, then set the Drivers properties in the Properties Panel (n)
If you only need to copy the channel without any operations, you can set type="Averaged Value".
Otherwise, you can choose the type you need:

That a nice way to do it.  I was wondering about anything a little easier to use, but that is fore sure a way to achieve it.  Thanks !


text:
How can I get HDRI shadows in an Eevee scene?
I'm currently testing Eevee.  Seems so promising !
Here, i'm trying to make my Eevee render the closest I can to my previous render Cycles of the same scene.
This scene do not have any lights but an HDRI background.
Thing is, the renders looks very, very different.  How can I improve this ?
Cycles:

Eevee:

And here's the blend file.
Thanks a lot.

First, the reason for the lighting difference is that in the scene you provided, everything is lit by a World HDRI only. Eevee by default can only produce shadows from Light objects, so even if you turn the respectable options on, there won't be any indirect shadows visible. This is a technical limitation. Duarte in the linked answer elaborates on this, so there's no need to re-iterate everything here.
However, there is a quick solution to at least get a lot closer to the Cycles render: Adding an Irradiance Volume Light Probe allows you to bake the lighting solution into the scene dynamically.
To do that, in the 3D Viewport use Shift + A -> Light Probe -> Irradiance Volume.

Scale it up to encompass the areas of your scene which are visible through the camera. After that, in the Render Settings, use Indirect Lighting -> Bake Indirect Lighting. The scene will jitter a bit while the solution is baked. Afterwards, it should look something like this:

Thanks for this description! This seems to work well for a static scene.
However, baking the lighting does not work if (for example) I have a node based world sky with changing colors. Do you know of any solutions outside of rendering in cycles that would allow reasonable shadow casting?

@tyler Just bake it on each frame?

@tyler just came across an add-on that could do the job for animations, though I have not tested it myself yet https://gumroad.com/l/PgyXc

license: Creative Commons - Attribution Share-Alike - https://creativecommons.org/licenses/by-sa/4.0/


text:
Why are some of my transparent objects rendering as black?
I'm trying to render an image on Cycles, I have a group of grass meshes with a transparent material, but when I rendered the image they looked like this, I tried using a Transparent BDSF node with a mixed Shader node but it didn't work, as you can see, some straws seem to be transparent, but the rest are not (all straws use the same material), my guess is that the rays stop at some point because of the plane mesh, any solution?

Does this answer your question? Black artifacts when looking through many transparent objects? and https://blender.stackexchange.com/questions/90409/why-are-my-renders-of-glass-turning-out-strange/90416#90416

https://blender.stackexchange.com/questions/42023/transparent-textured-planes-produce-black-artifacts

all_licenses: Creative Commons - Attribution Share-Alike - https://creativecommons.org/licenses/by-sa/4.0/


text:
How to animate text for 2D animation?
How do I animate text in a 2D animation? I would like to play around with text alpha (opacity), scaling the size and position. In my animation, I will use text as title and main points for my video. Can I directly animate the text object or  must I change into other types of object before animate it?
When text opacity is 0:

When text opacity is 1:

Basically, I just want the text to appear at a particular frame (keyframe) and hide it after a period of time.

everything is possible, it can simply be an image texture with a transparent background as you seem to say, but what kind of animations are you talking about?

edited: basically, i just want the text to appear at a particular frame(keyframe) and hide it after a period of time. btw, i just use blend mode to change the opacity of the text. is there any other way to change it opacity the same way we change (transform) it size?

so if you want it to gradually appear you can use the factor of a Mix Shader in order to switch from a Transparent shader to your Image Texture. If it appears from a frame to another you can just keyframe its visibility in the Outliner.

alright thank you sir for your favour :). I will try to play around with the Mix Shader later.

You can also use Map Range nodes in your Node Tree, which gives you more flexibility, because they can be modified by other nodes. https://youtu.be/Fh9kB2zCtnU


text:
Is there a Blender Virtual Camera? Or How to create a Virtual Camera?
Two pronged question: Is there currently an addon or process in which I can use a virtual camera in Blender? (a virtual camera is like this - https://www.youtube.com/watch?v=MAFVglxzkhI) I mainly want to be able to do that within blender but I have not found anything like that. Including in this post (Any tools to capture movements from a mobile phone to Blender?)
Second question is if there is no system out there like that, then how can I go about making a virtual camera addon myself? I do not have a VR system so I cannot test a system like the video above so I would like to make a bootleg version using my smart phone (both iOS and android something like this but connected to the camera instead - https://www.youtube.com/watch?v=YcylkhyauC0 or https://www.youtube.com/watch?v=xMEea6drOPA). I have made apps for both android and iOS and I would like to make an app that connects wired or wirelessly into blender (Similar to Unity Remote - https://www.youtube.com/watch?v=RdhliD0zupg) Once connected I would use the smart phone to connect to the blender camera and connect as a bootleg virtual camera  but I have no idea how to go about this and I would like some help please.
If anyone out there could direct me in the right direction where I can find further information on how to go about this I would highly appreciate it thank you!

Do you realize, that the rig in the video uses motion tracking markers and a motion tracking system? You will need a way to track your camera. Motion tracking or a VR System are the main options.

I don't think it is a good idea to use a phone for running Blender. You will probably need to come up with some other hardware solutions to display the scene that would be portable as in the example video.
If you know how to get movement and orientation data from some device, moving camera in Blender via Python is not a big deal at all. You could use an accelerometer and gyroscope sensor connected to some microcontroller board - probably would be easiest to use an Arduino, maybe have a look at this one that comes with Bluetooth Maybe then receive data with pySerial...
Once in Blender, you can take any camera and move it with scene update Application Handler continuously. It's as easy as bpy.data.objects['Camera.001'].location = ... and bpy.data.objects['Camera.001'].rotation_quaternion = ... You might want to add functionality, like for example recording the movement to keyframes and so on. That is obviously also achievable with Blender's Python API.
I suspect that you might want to add quite a lot of additiona features like that and probably some sort of an interface so at the end of the day, this might not be the most suitable/enjoyable first project to try for someone without any knowledge of Blender's Python API. You might want to dedicate some time to learning to use it first.

Thanks for the advice! Ill take to learning Blender Python then.

Recently an iOS developer released virtual camera app for AutoDesk Maya. The plugin is open source licence for development to other 3d softwares. I contacted him regarding the plugin for blender. Waiting for his reply. Also contacted him about android version also

Is there a forum discussion or something where BSE users can see progress, contribute?

Thanks V GK, would you be able to link to the virtual camera app for maya? I was unable to find it

What is the name of that app?....

It's called virtucamera.com


text:
Archimesh, properties?
In relation blender 2.79 and the archimesh tool shelf missing, which was answered in Archimesh is not displayed in the Tool shelf
The properties panel is disabled. For example when i add a column i cannot change top or base or add an arch. What do i need to do to enable it?
I posted a follow up there, apologies for that.

You mean you want to adjust the parameters of the wall for example

Provide image what you mean

Still trying to figure out how to attach an image. In the meantime, add a column, you will find the properties (in the T panel) grayed out... That's for Blender 2.79, in 2.78 its fine.

Press edit -> Press ctrl+G (or click the image icon) browse the image -> click on add picture and after loading the image dont forget to save edit at the bottom

And oh, if it makes any difference, i am using linux.

See https://blender.stackexchange.com/questions/8262/what-is-causing-disabled-options-when-adding-a-mesh-curve-object-to-the-scene

Go to User preferences -> Editing-> (check mark on) undo
Do not forget to save user setting below

No, that's not what i mean.

@agor check the new answer edited

Wow! I never thought of that, a million thanks!


text:
Scaling keeps resetting after set keyframe in Blender action
I'm new to Blender animation. I'm working on an action for my animation. In this action, I scaled a bone like the photos below. But when I play action, it keeps the same scale and the values didn't interpolate. When I move the cursor between frames, it also doesn't make any action.
What did I miss here guys ?

my first 3d animation professor used to answer every question with the same initial answer... "Did you apply Loc/Scale?" not applying it to your mesh can result in the stranges things...
Also, I fail to see what is changed? your settings for scale are the same on frames 3 and 5. It looks like you put whatever you keyframed is on frame 0, and frames 1 - 20 all have the same data... since your animation is set to run from frame 1 to 20 I don't believe it ever reaches frame 0 to take on whatever changes you made in that frame...
...and what change are you making anyway? a single frame in the begining of the animation with out anything to change too just makes the single change to the entire timeline... you need a starting value and a target value.. such as the scale of x in frame 1 being 1, the scale of it on frame 10 at 2, and the scale of it at frame 20 being put back to 1, (which would cycle the bone up and down with a bit of a hitch at the end...)
Anyway, I could easily be wrong, but I think your best bet is to keyframe inside your animation timeline, and make sure you have applied your mesh's rot/scale

Thanks @richwoo. I did made a change. In frame 0, i put scale value in default value (ex : scale x,y,z - 1,1,1). And i changed the value of scale z down to 0.8 in the frame 5 that i thought it would made a animation of bone 9 scale down. But when i move around from frame 0 and frame 5 to see how animation work, the value didnt interpolate and the value of scale z in frame 0 become the same with frame 5 (i lost here).

Btw did I make wrong way to apply scale on mesh ? Because I do it in basic way that I will make change scale on pose mode (the left screen) and insert keyframe to action timeline (right screen).


text:
Ctrl-C not working
I am trying to make an optical encoder, so I want to cut a lot of holes at even intervals around a disk. I am trying to make a macro to apply Boolean modifiers, rotate 5 degrees, and repeat. All the tutorials I have watched say to copy the commands out of the info screen and paste it into a text editor, but when I hit Ctrl- C it doesn't seem to do anything. There's nothing in the clipboard to paste.
I have checked that my keyboard bindings are correct, and I am not sure what else to check. Do I maybe need to be in a particular mode to be able to copy out of the info screen?

Have you clicked on any text and selected it before copying?

Yes. I selected all the lines I wanted to copy, it highlighted them. I tried closing and opening blender and trying again. I tried restarting my computer as well.

Your mouse cursor must also remain hovering the info window while copying

I think it was, but I will try that and make sure. Thank you.

Thank you for the replies. It looks like the problem was my understanding of the text editor window. I just opened it as a new pane and tried to paste. It looks like I needed to "create text block" first.

The only thing, that I can think of that would cause issues like that is if your mouse cursor is not over the editor you are trying to copy from. Blender needs to know, which part of it you are trying to copy stuff from so you need to hover the mouse over the area that your selected text is when you copy it.


text:
Delete pickle file with python within Blender
Does anyone know if it's possible to delete a pickle file with python in Blender please ?
I need to store some data to use them later. I've created a pickle file to store them (so, maybe is not the best way for that).
When I've finished my work, I need to delete the pickle file with an operator after having restored my data saved in the pickle file.

The standard filesystem functions available in python can be used within blender.
import os
os.remove(path) # a single file
os.rmdir(path) # an empty folder

The python docs include more info.

Sorry for the delay. Thanks a lot for your answer.


text:
Blender 4.0 - viewport control buttons disappeared
The first image is my Blender:

And I need those viewport control buttons on the second image:

Make sure that Show Gizmos is enabled:

No matter if you enable the Overlays or not, what @Geri said is legitimate: they do not enable the gizmos - see your own screenshot: the overlays are disabled, but the gizmos are visible. But if Show Gizmos is disabled, you can enable the overlays as much as you want, the gizmos won't show. Well, Daniela found it so who cares... but maybe future users are not so canny.

Sorry i still don't get it, the screenshot shows that the gizmos are disabled, the solution was to enable them back, what do ypu mean by "they do not enable the gizmos?" Maybe give your own answer to make it more understandable?

@moonboots You just marked the wrong button in your image. The viewport controls marked in the question's second screenshot which are missing in the first, are enabled by the Show Gizmo button, the one that looks like bow and arrow left of the Show Overlays button (the one you marked and incorrectly called Viewport Gizmos).

Oh of course thanks   ;)


text:
What's the difference between camera mapping and UV unwrapping?
I came across the term 'Camera mapping' and searched for some tutorials. I found that it's just pasting the images on objects, very much like UV unwrapping.
So what is the difference?

Camera mapping is the most often mispresented camera matching but the actual camera mapping is well explained here:
https://www.youtube.com/watch?v=B9r9tKX5olY

Regular uv-unwrapping:

Camera mapping:

Camera mapping is basically a type of uv-unwrapping.
In general you use regular uv-unwrapping if you want to apply a texture directly to a face, and camera mapping if you want to apply an image taken from the perspective of the (viewport) camera to an entire mesh.

It is a method which allows you to make an illusion of moving through some real scene.
You match the virtual (Blender's) camera with the real footage camera, take a "screenshots" from the footage, edit them by a photo-editor and map those photos to Blender objects which help to mimic the real scenery. This way you can "reconstruct" the real scene and add custom CG objects into it.
https://www.youtube.com/watch?v=B9r9tKX5olY
It is often misrepresented as Camera Tracking / Matching which is a different thing.

it uv unwraps for the whole scene(that is the video I took the tut from) and what's the big difference from uv unwrapping, One thing is that you don't have to worry about the focal length to match the perspective, are there any other.

Unwrapping is just a part of the whole Camera Mapping process you need to realize to create the real scene reconstruction. And you use camera matching for that.

Camera Mapping might reference the Camera output of the Texture Coordinate node, which provides a similar result to UV-unwrapping using Project from view, with the difference that it's depending on the current position of the camera in every frame and not calculated once.

authors: Альбина Сайфиддинова


text:
Wrong particle spawning position
I have a topping on donuts which are made using particles

Viewport mode. If I change some parameters in the particle system, they are spawning correctly.

Render mode they all spawn on some exact faces or just don't spawn at all.  This is incorrect.

This is the picture in the viewport:

and this is how they look in the final render:

I see two images of Object mode, or I do not understand the images.  Can you show the actual render? I do not see it.

I am only guessing at the Russian in the screen capture.

Lets assume the donut has the same number of particles for the animation.
Make sure the lifetime is large enough such as 400 frames.
If I wanted to see all Particles visible from frame 1 to 400

All the particles could be emitted in Frames 1 to 2. (Quick Birth)
Lifetime can be large as in 400
I might [bake] the particles.  I might save, close, and open,  the file to refresh.  Particles can sometimes be out of synchronization.  Sometimes change a value by a small amount might help or running the animation from frame 1.
Ezvinete. Ya ne ponimaish pa Russki.


text:
Blender plane effect from blender render to cycles render

On blender render it looks like this but when i try to do it in cycles it doesnt look the same(effect from deviantart) its a bunch of planes with an image to make an effect, Please help.

Could you post an image of the cycles result?

Yeah sure give me a minute or two

As they are different  two render engines, you'll need to "convert" your materials. You can give a try with the solution proposed here. If you still have trubles in figuring it out, I suggest you to post the material's settings/node tree so we can heve a look.

I think it's better not to give up to ready to use tools but just once learn how the transparency work in cycles, and then just use the knowledge.
https://www.youtube.com/results?search_query=transparent+textures+in+cycles
It's fairly easy. All you need is your png image's Alpha output as a mix node Factor to mix your image color in a Diffuse shader and a Transparent shader.


text:
import PhysicsConstraint not working
The code below is not working.
In the system console it says no module named PhysicsConstraints
import PhysicsConstraints
from bge import logic

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

if (c["init"] == 0):
    c["init"] = 1
    physicsid = c.getPhysicsId()
    vehicle = PhysicsConstraints.createConstraint(physicsid,0,11)
    c["cid"] = vehicle.getConstraintId()
    vehicle = PhysicsConstraints.getVehicleConstraint(c["cid"])

# Wheels

    act1 = cont.actuators["wheel1"]
    wheel1 = act1.owner

    act2 = cont.actuators["wheel2"]
    wheel2 = act2.owner

    act3 = cont.actuators["wheel3"]
    wheel3 = act3.owner

    act4 = cont.actuators["wheel4"]
    wheel4 = act4.owner

    wheelAttachDirLocal = [0,0,-1]
    wheelAxleLocal = [-1,0,0]

    wheelRadius = 0.8
    suspensionRestLength = 0.28

    hasSteering = 1
# wheel1
    wheelAttachPosLocal = [1.0 ,1.5, 0]
    vehicle.addWheel(wheel1,wheelAttachPosLocal,wheelAttachDirLocal,wheelAxleLocal,suspensionRestLength,wheelRadius,hasSteering)
# wheel 2
    wheelAttachPosLocal = [-1.0 ,1.5, 0]
    vehicle.addWheel(wheel2,wheelAttachPosLocal,wheelAttachDirLocal,wheelAxleLocal,suspensionRestLength,wheelRadius,hasSteering)

    hasSteering = 0
# wheel 3
    wheelAttachPosLocal = [1.0 ,-1.4, 0]
    vehicle.addWheel(wheel3,wheelAttachPosLocal,wheelAttachDirLocal,wheelAxleLocal,suspensionRestLength,wheelRadius,hasSteering)
# wheel 4
    wheelAttachPosLocal = [-1.0 ,-1.4, 0]
    vehicle.addWheel(wheel4,wheelAttachPosLocal,wheelAttachDirLocal,wheelAxleLocal,suspensionRestLength,wheelRadius,hasSteering)

else:

    vehicle = PhysicsConstraints.getVehicleConstraint(c["cid"])

    #vehicle.setSteeringValue(steer,0)
    #vehicle.setSteeringValue(steer,1)

# Acceleration

    vehicle.applyEngineForce(c["force"],0)
    vehicle.applyEngineForce(c["force"],1)

# Brakes

    vehicle.applyBraking(c["brake"],0)
    vehicle.applyBraking(c["brake"],1)
    vehicle.applyBraking(c["brake"],2)
    vehicle.applyBraking(c["brake"],3)

# Suspension

    influence = 0.1
    vehicle.setRollInfluence(influence,0)
    vehicle.setRollInfluence(influence,1)
    vehicle.setRollInfluence(influence,2)
    vehicle.setRollInfluence(influence,3)

    stiffness = 10
    vehicle.setSuspensionStiffness(stiffness,0)
    vehicle.setSuspensionStiffness(stiffness,1)
    vehicle.setSuspensionStiffness(stiffness,2)
    vehicle.setSuspensionStiffness(stiffness,3)

    damping = 0.5
    vehicle.setSuspensionDamping(damping,0)
    vehicle.setSuspensionDamping(damping,1)
    vehicle.setSuspensionDamping(damping,2)
    vehicle.setSuspensionDamping(damping,3)

    compression = 0.5
    vehicle.setSuspensionCompression(compression,0)
    vehicle.setSuspensionCompression(compression,1)
    vehicle.setSuspensionCompression(compression,2)
    vehicle.setSuspensionCompression(compression,3)

    friction = 1.0
    vehicle.setTyreFriction(friction,0)
    vehicle.setTyreFriction(friction,1)
    vehicle.setTyreFriction(friction,2)
    vehicle.setTyreFriction(friction,3)

The logic editor window looks like this:

What should I do to run this code?

https://www.blender.org/api/blender_python_api_current/bge.constraints.html

replace
import PhysicsConstraints
...
vehicle = PhysicsConstraints.createConstraint(physicsid,0,11)
...

with
import bge.constraints
...
vehicle = bge.constraints.createConstraint(physicsid,0,11)
...

and so on.


text:
How to use spray in ocean modifier
ocean modifier after blender 2.90 has a new feature called the spray in foam subpanel,and I have no idea how to use the spray direction map it gives me.

Don't know if this YT video helps?

@JohnEason That clip is for an add-on, so not totally relevant here

One way is combination of "Ocean" and "GeometryNodes".
the "Foam" and "Spray" both are attribute, they can pass through Geometry Input into GeometryNodes process.

Ocean is great.

This is a very powerful answer, thank you!  I wish you went into a bit more technical detail but I can certainly reverse engineer what you've done and I'm going to dabble. Cheers!


text:
Trying to replicate a Potlight light appearance

Hi, I'm new to this forum and have been using blender for a few months now.
I'm trying to get this double cone appearance with the pot lights I've set up. I've tried various things like double light sources and even a emitter. But I just can't get this focused lens appearance.
If there's a way to add a b/w ringlike mask to the light source, I haven't figured it out yet. And I'd like to avoid needed multiple lamps per Potlight if possible.
Does anyone have a straight forward solution for this?
Thanks in advance

If you're using Cycles, a straightforward solution is to use an IES texture in point lights.
Download a suitable IES file, 'Use Nodes' in a point light's shader, and plug an IES Texture node into its emission strength, referencing the file:

Strictly speaking, your model should be to scale.

At the time of writing, you might find something suitable here

Those are called IES profiles
https://docs.blender.org/manual/en/latest/render/shader_nodes/textures/ies.html
https://ieslibrary.com/en/home

Thanks a lot! Only 300k lamp profiles to go through! ;) I guess the only things I just discovered is that it doesn't require a spot specifically, and that the radius needs to be 0 or close to it.
But yeah, the IES is exactly it. Much appreciated!


text:
Light source causing Dark spot instead of light
Alright, I can't seem to figure this out. Using cycles, I've added a light, originally a IES point light, but I've also tried a basic spotlight and I get the same basic problem.
As you see in the images, it's casting a dark shadow instead of light. Looking as the cone ref, its not the frame of my object is interferring that I can see or understand.
This shadow only goes a way if I move the light almost half way down the length, or move it well away from this column.
I tried changing the surface colour and materials (thinking that gold was causing some issue) but it didn't appear to change it.
I've included a dropbox link (I don't think I can link actual files here) of this setup, with 3 lights, my original lamp, a Spotlight lamp in the same position as well as a lamp moved down to where it doesn't have this problem.
Can anyone "illuminate" me on this? Thanks.

https://www.dropbox.com/s/i4956x11pu2aa73/Pilaster%20test%20-%20IES.blend?dl=0

as @moonboots says.. or check Autosmooth in the object's Data tab > Normals panel. The front face is interpolating the normals over from the faces it's connected to, on the sides.

It looks like it's not due to the light but to the Shade Smooth of your object, Shade Flat instead and it will work correctly.

I don't really understand why, but yeah that works. Thanks

I don't know either  :/


text:
Different geometry Viewport vs Render in Cycles
I'm working on a project and I'm stuck on this stupid thing.
This object looks completely deformed on the render vs how I see it in the viewport.
The project is a bit messy, I used .xps files from ripped games models, so I don't even understand what could be wrong.
I checked layer visibilities and it should be fine, I tried removing the armature modifier but it's still the same. They're both at 32 samples. I'll attach the blender file and the screenshots. THX!
https://drive.google.com/file/d/10duDmQuQjRbMByTHLNjWnmO6YzCnLByb/view?usp=sharing

Your objects are duplicated. Try click selecting then moving them. I looked at the star and there are three duplicates there in particular. This fixed the shading issue.


text:
Animation Nodes's vector distance : can't make it work like in the official example
I was reading this AN documentation page about Vector Distance.
I don't know if it is still up-to-date, but I recreate the same setup and I can't make it work the same way:
it seems that the position of my empty is ignored.
Can anyone help ?

Here's my blend.

please also provide a screenshot of your node setup. Maybe this question can be answered with looking at the actual .blend file (I can't open it right now because I'm not at my pc)

The Empty in your blend file isn't in the boxes' plane but 8.4 BU above it. With the current node setup the boxes will only be affected when the Empty is closer to 1 BU to the boxes' center, which perhaps didn't happen if you only moved the Empty in top view.

If the Empty is moved within the Z=0 plane the boxes will scale correctly.
You might also want to consider adding a Math/Multiply node after the Vector Distance node, or use smaller boxes, if you want to affect more than one box at a time. With the current size of your boxes only one of them will be closer than 1 BU to the Empty.

"the boxes will only be affected when the Empty is closer to 1 BU to the boxes' center" > how do you know that ?

@gordie Strictly speaking, “affected” probably is the wrong word. But the Vector Distance node is connected to a Clamp node. Any distance greater than 1 BU will be clamped to the value 1 which will result in a scaling factor of 1, i.e. you won't see any change. If you keep the current dimensions of the boxes you can add a Math/Multiply node to scale the distance, e.g. by 0.05. Then the boxes will start to shrink as soon as the Empty moves closer than 20 BU to the boxes' centers.


text:
is it possible to move/drag the origin of a node link?
We can move a node links from one socket to another by simply dragging it.
But is there a way to drag the "origin" of a link ?

Thanks!

Hold CTRL and move with your mouse to move that.

just for fun:
you can hold Shift and then drag with the right mouse button over a line, which creates a "reroute" point. This you can move freely with G (or/and mouse)

you can add as many reroutes as you want.

That's not what I was searching for, but anyway this is an answer of another question I had :) PS I edited the question.

i updated my answer


text:
mesh animation & boolean: avoid bugs & glitches (Cycles)?
I'm working on an isometric animation where a road scrolls.
The road should appear only within a specific "domain", so I added a boolean modifier on the road mesh, so it is constrained within the desired space.
Thing is, I can't make it work as it displays a lot of bugs & glitches.

How could I fix this / achieve the same effect ?
Here's the project file if you want to have a look.
Thanks !

The sides disappearing is because the cube you are using for the road domain is a little bit too small, scale it about 0.03 bigger on the Y axis and you will get a better boolean result.
Your second problem is the caps on the ends of your road mesh. By using an array modifier you get these repeated along the road, this leads to the ends appearing and disapearing as it moves along. For this remove the faces at both ends and apply the array modifier, then recap the ends.

wow thanks a lot, i'll give a try.  Regarding your first point (domain a little bit too small), do you know why it would be too small ? Is there something to understand there ?

@gordie just that as it is, it is the same size as the road, slight variations in float calculations (maybe the displace can alter this a bit as well) mean it can fall on either side of the boolean calculations, sometimes it is inside, sometimes outside, by making it a little bit bigger you ensure it is always outside.


text:
Cloth physics : drop/unroll a cloth sheet from the top of a building
I'm working on a project and I have a video shot where I would like to drop a cloth sheet through the top of a building - Well, it's not exactly a sheet, it's a banner, but that is the idea.

At the start of the animation, I would like the banner to be "rolled" or something (not deployed), then that it deploys itself using gravity.
There should be pins at the top (to fix it) and a weight at the bottom (so the banner doesn't "fly" to much).

I started to work on it: I have the cloth, I have 3 vertex groups (topPins, bottomPins, allPins), the topPins are attached to the top cylinder and the bottomPins to the bottom cylinder; which has rigid body enabled.
But I guess there is other things to do since... It doesn't work : the bottom cylinder keeps falling - and instead it should remains attached to the cloth, depending of its physic resistance/elasticity, I guess.

Also, I don't know how to handle the start situation.
Could someone help with some advices ?  Here's the .blend file if you want to check.
If this is too complex, I think i'll end up with a simplier idea (just wind on the deployed banner)
Thanks a lot !

I found out this on Youtube.
It looks like a great idea (roll the cloth curtain before unrolling it).
Tutorial for Blender - Curtain Call - Rolling up Material
I had several attemps but cannot reproduce its setup; maybe because of the Blender version ?
My actual .blend here if anyone wants to try...

Here is another way to go.  Instead of using pinning to connect the bottom vertices of the banner to the bottom cylinder, parent the bottom cylinder to the bottom 3 vertices of the banner.  (Keep the pinning to the top cylinder so the top of the banner stays put.)  That way, as the bottom of the cloth naturally falls due to gravity, the cylinder will fall with it.  You would need to adjust the mesh of the banner to a staring position where the bottom vertices are near the top ones, and probably "bunch up" the rest of the flag so it's all up at or near the top.
Here is a quick and dirty implementation of that idea:

This seems cool, but will the cloth be affected by the weight of the bottom cylinder ?

No, I'm sorry to say it will not (if that's the desired effect).  I am honestly not sure if there is a way to do a two-way connection between cloth and a rigid physics object (in that the rigid object's movement deforms the cloth, but the cloth modifies the movement of the rigid object by tethering it.)  If a guru here knows how to do that I'd be very interested, my experiments in that regard failed.

Or maybe should I work with vertex weights ?

You need to stop the fall of the bottom cylinder at some point.
Using the animation keys, make the bottom cylinder falls from position A, banner rolled up at the top, to position B, banner fully deployed. Once it's at position B, make it not affected by gravity anymore, so that it remains in place and your banner remains fully deployed.
As for making the banner unroll, you could use a curve on the banner object, make it tightly rolled like a spiral, then animate the curve to make it go from a tight spiral to a straight line as the bottom cylinder falls, which would effectively look like the banner is unrolling from the top.


text:
Same Material with different key frames
Is it possible to have same (single) material object applied to different objects (mesh or curves) but have different key frames for each (mesh or curve)?
I want to fade-in my text (which is curve) like a window so the text appear fade-In gradually character wise. I have created a material slot, added TransparentBSDF and MixShader Node, but separate Material slot for each Character (curve) because each character fade-In start time index is slightly greater than the previous.
Currently I am doing this using Python Code (Blender 2.83)
fade_objects = bpy.context.selected_objects

frame_dif = 2
frame_length = 40
frame_start = 0

fade_frame_start = frame_start
fade_frame_end = fade_frame_start + frame_length

for fade_object in fade_objects:

    # Create Material Object and Apply to character curve
    mat = bpy.data.materials.new('Fade')
    fade_object.data.materials.pop()
    fade_object.data.materials.append(mat)
    mat.use_nodes = True
    mat.blend_method = 'BLEND'

    nodes = mat.node_tree.nodes
    links = mat.node_tree.links

    #Creating New Nodes
    node_transparent = nodes.new('ShaderNodeBsdfTransparent')
    node_mixshader = mat.node_tree.nodes.new('ShaderNodeMixShader')
    node_bsdf = nodes['Principled BSDF']
    node_matout = nodes['Material Output']

    #Linking Nodes
    links.new(node_transparent.outputs['BSDF'], node_mixshader.inputs[1])
    links.new(node_bsdf.outputs['BSDF'], node_mixshader.inputs[2])
    links.new(node_mixshader.outputs['Shader'], node_matout.inputs['Surface'])

    #Adding Key Frame for MisShader Node (Fade In)
    node_mixshader.inputs['Fac'].default_value = 0
    node_mixshader.inputs['Fac'].keyframe_insert('default_value', frame = fade_frame_start)
    node_mixshader.inputs['Fac'].default_value = 1
    node_mixshader.inputs['Fac'].keyframe_insert('default_value', frame = fade_frame_end)

    #Add frame difference for next character for sliding effect
    fade_frame_start += frame_dif
    fade_frame_end += frame_dif

This code create n number of material slots as my n number of curves.
Can I do this with single Material Object with different values for MixShader node for each curve?

You can't directly have different keyframe sets for a material but you can use for instance the object pass index attribute, plug it into your factor and then keyframe the object pass. More info : https://blender.stackexchange.com/a/183384/86891

Use drivers for this.

Object Info Node

As mentioned by @Gorgeous can use an object info node.
Control object emission strength (not material)
Using Object.color

Object color,
same as Color in the
Properties Editor ‣ Object ‣ Viewport Display

For the example below am creating two new nodes, an object info node, separating the RGB via a separate RGB node and feeding this into the mix node factor.
Unfortunately I am not aware of how to use the Alpha channel, so am keyframing and using the Red channel.
This way the action is created on and belongs to the object using the material.
Minor adjustment to your code to add only one material with  the new nodes and links, and keyframe the object's red color in the loop.
import bpy

fade_objects = bpy.context.selected_objects

frame_dif = 10
frame_length = 40
frame_start = 0

fade_frame_start = frame_start
fade_frame_end = fade_frame_start + frame_length

# Create Material Object and Apply to character curve
mat = bpy.data.materials.new('Fade')

mat.use_nodes = True
mat.blend_method = 'BLEND'

nodes = mat.node_tree.nodes
links = mat.node_tree.links

#Creating New Nodes
node_transparent = nodes.new('ShaderNodeBsdfTransparent')
node_mixshader = mat.node_tree.nodes.new('ShaderNodeMixShader')
node_bsdf = nodes['Principled BSDF']
node_matout = nodes['Material Output']

objinput = nodes.new("ShaderNodeObjectInfo")
seprgb = nodes.new("ShaderNodeSeparateRGB")

#Linking Nodes
links.new(node_transparent.outputs['BSDF'], node_mixshader.inputs[1])
links.new(node_bsdf.outputs['BSDF'], node_mixshader.inputs[2])
links.new(node_mixshader.outputs['Shader'], node_matout.inputs['Surface'])
links.new(objinput.outputs['Color'], seprgb.inputs['Image'])
links.new(seprgb.outputs[0], node_mixshader.inputs['Fac'])

for fade_object in fade_objects:
    fade_object.animation_data_create()
    fade_object.animation_data_clear()
    fade_object.data.materials.clear()
    fade_object.data.materials.append(mat)
    fade_object.color[0] = 0
    fade_object.keyframe_insert("color", index=0, frame=fade_frame_start)
    fade_object.color[0] = 1
    fade_object.keyframe_insert("color", index=0, frame=fade_frame_end)
    #Add frame difference for next character for sliding effect
    fade_frame_start += frame_dif
    fade_frame_end += frame_dif

Other things to consider would be using drivers on the color field based on the current frame, or by using a single action that is attached to each object and offset via the NLA

With V2.92 and the new Attribute node, you can achieve it with a single driver in the material.
First, you need to add a custom property to all your objects. Then, compare it with the current frame. Choose a different offset for each object to make them appear in sequence.
Here's the code :
import bpy
new_mat = bpy.data.materials.get('Fade In Material')
if not new_mat:
    new_mat = bpy.data.materials.new('Fade In Material')

frame_offset = 50

new_mat.use_nodes = True
node_tree = new_mat.node_tree
nodes = node_tree.nodes
nodes.clear()

links = node_tree.links
links.clear()

# Nodes :

new_node = nodes.new(type='ShaderNodeBsdfPrincipled')
new_node.location = (10.0, 300.0)
new_node.name = 'Principled BSDF'

new_node = nodes.new(type='ShaderNodeOutputMaterial')
new_node.location = (300.0, 300.0)
new_node.name = 'Material Output'

new_node = nodes.new(type='ShaderNodeAttribute')
new_node.attribute_name = 'frame_start'
new_node.attribute_type = 'OBJECT'
new_node.location = (-665.818115234375, -101.93711853027344)
new_node.name = 'Attribute'

new_node = nodes.new(type='ShaderNodeMath')
new_node.location = (-482.0205383300781, -93.33195495605469)
new_node.name = 'Math'
new_node.operation = 'SUBTRACT'
driver = new_node.inputs[0].driver_add("default_value").driver
driver.expression = "frame"

new_node = nodes.new(type='ShaderNodeMath')
new_node.location = (-282.9521484375, -71.30279541015625)
new_node.name = 'Math.001'
new_node.operation = 'DIVIDE'
new_node.use_clamp = True
new_node.inputs[1].default_value = frame_offset

new_mat.blend_method = 'BLEND'
new_mat.show_transparent_back = False

# Links :

links.new(nodes["Principled BSDF"].outputs[0], nodes["Material Output"].inputs[0])
links.new(nodes["Attribute"].outputs[2], nodes["Math"].inputs[1])
links.new(nodes["Math"].outputs[0], nodes["Math.001"].inputs[0])
links.new(nodes["Math.001"].outputs[0], nodes["Principled BSDF"].inputs[19])

# Link Material to objects :

for i, obj in enumerate(so for so in bpy.context.selected_objects if so.data):
    obj["frame_start"] = i * frame_offset
    if obj.data.materials:
        obj.data.materials[0] = new_mat
    else:
        obj.data.materials.append(new_mat)

Resulting shader (There is a driver to the current frame in the first Math node) :

Result with a few objects :


text:
How do I make the popup menu that appears after you use a tool open at the cursor?
In Blender 2.8+ when I execute a command such as extrude or bevel the property pop-up menu opens in the bottom left of the screen. Is there an option to set so that property pop-up menus open at the cursor?

Hello :). Just press F9 and it will show up on your cursor.

That worked, thank you.

Is there any way to make it permanent so that I don't have to always hit F9?  Like set that as a default?

I don't think that's possible currently (without add-ons), but this sounds like a great workflow improvement to implement. maybe submit to https://blender.community/c/rightclickselect/


text:
Delete keyframes quickly without the menu in timeline
I want to delete keyframes by pressing X without the "menu".
How can I block that menu?
I looked at the keymap editor, I thought, maybe the key is "DOPESHEET_MT_delete" code but I'm stuck.
There must be a new hotkey for this, that users can choose.

When the menu opens up, right click on "Delete Keyframes" and assign a shortcut.
In the keymap editor, disable the "Confirm" option for the newly added keymap item.
Remove the existing X delete keymap item in the keymap editor.


text:
Why are there borders around faces when I extrude?
I'm a beginner at blender and I'm following a tutorial on extrusion but I can't seem to figure out why there are borders when I extrude. I'm trying to make it so that the middle 3 cubes come down together without the borders.

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

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

You might want to try version 2.9 (still in alpha as of July 2020)
There is a new function to Extrude Disolve and Intersect that will make exactly what you want to do.
If you extrude inwards it will deal with unwanted duplicated faces.

Watch this video:
https://youtu.be/FlhAjyLnvrY


text:
How to pin cloth to another mesh without an armature
I've been messing around with some simple skirt models and I was wondering how I could pin the cloth so that when the mesh moves the cloth stays with the mesh.
I currently have a skirt draped over a mannequin without an armature and when I make the mannequin spin the skirt slides around her waist instead of moving along with it.
As a visual I made a red stripe on the mannequin and the skirt. After 1 spin and a half the skirt only does almost a full spin.

Looks great. Is it a circle shape at the beginning? -- If you define a pin group you can rotate the skirt mesh with keyframes or just parent it to the mannequin. For the pin group: create a vertex group, assign the top vertices of the skirt to it, then use this vertex group in the cloth settings Shape > Pin Group

@Blunder The shape I used was a cylinder, after some testing I figured out that it was not possible to have the same type of pin on a cylinder instead of a plane. When I used the plane it worked but the outcome was not nearly the same as I hoped

As Blunder said, if the meshes are separate, you can parent the skirt to the mannequin. That way, when the mannequin moves, the pinned, not-simulated-cloth parts of the skirt should move with the mannequin, the same way that armatures work, but not with armatures.

Is there a way that a cylinder can be pinned to the mannequin instead of a plane?

What do you mean? You can pin any vertex groups on any mesh, and the pinned vertices won't be simulated, which means that they'll move with parented objects.


text:
Unwanted mesh selection through other objects with x-ray off
I'm new so I don't know if this is a bug, or if I'm missing something.
Here I am trying to deselect some faces.

It doesn't select through the current object being worked on, only other objects.
Why should an object that is occluding my vision not also occlude the selection, considering I can just turn on x-ray to do that?
Restarting Blender didn't work.
Blender 3.1.2

After messing around, I figured something out that works okay.
I just realized you can go into edit mode on multiple objects, and it saves your selection when switching between modes.

When in edit mode, CTRL+LMB select the object that you want to block the selection.
Press TAB twice to go toggle to Object Mode and back to Edit Mode.
Make your selection.
TAB back to Object Mode then LMB select only your original object.
TAB back to Edit Mode.


text:
How do I apply a consistent wave pattern along a spiral curve in Geo-Nodes 3.3?
Elaboration on question:
To elaborate I want to have a wave pattern go along this spiral. The wave pattern needs consistency (i.e. currently in some sections of the spiral the wave pattern seems to fade while other parts seem to have a more consistent pattern - the pattern does not stay the same throughout) all the way through the curve because I will turn this curve into points. I will then instance a collection on those points. So, in the end I will have objects instanced along a spiral curve, that move up and down on the Z axis, in a consistent fashion.
Node Setup:
I want to note you can ignore the curve to mesh as I only put it there to give greater visibility in the picture but it won't be used in actuality. I have Color-ramp plugged into Math Node set to multiple to control the size of wave. Then plugged Combine XYZ node into switch. This is so the wave only takes place on Z axis. The Math node set to divide is to control speed at which wave flows.
Restatement of question and my current understanding:
I want to understand how to get a consistent wave pattern along a spiral curve. Note that the curve height and speed can already be controlled. Also note, that I understand that Scale determines how texture lays along curve but even when I change scale, things still don't become consistent... why do I not get consistency along curve? I marked in the photo where the wave pattern suddenly changes consistency. It seems to change at the maximum height of the bend of the spiral... not sure though.

If anyone could help it would mean a lot. Also if you anything that is superfluous please let me know.

Have you tried aligning the Wave Texture to the Z-axis instead of the X-axis?

@Vagabonk  That won't help :) .. see answers.

i would try it with sin like this:

result:

Your wave texture is in the wrong space. (Object Space). It is straight wave-fronts down the X of that space. Where the spiral runs across the wave, it will be steep. Where the spiral is parallel to the wave, it will be shallow:

Instead, as Chris shows in  his answer, you need a dimension that runs along the spiral:

Superfluous: the Switch node. For Z-only, you can always pass (0,0,your_Z) with Combine XYZ, or your_vector*(0,0,1) with Vector Multiply

The Wave (Sine) (X) texture returns  sin(whatever X you give it) By default Geometry Nodes works in Object Space or 'Position' ( measured in Blender Units, along the modified object's own XYZ axes, after any object level rotation and scale ) The X of that space runs along the Local X of the object. In my illustrations the plane is deformed by the same texture as the spiral. For the bottom result, we tell Wave to consider X to be measured along the spiral itself instead, by feeding it Spline Parameter (Factor) which returns 0,,1 along the splines's length.

Thank you @RobinBetts and Chris , I wanted to ask for a quick clarification. You mentioned that I was in the "wrong space". I am somewhat familiar with this concept in texturing - and how we can use the mapping node to correct for certain things. It seems to me that you used the "Spline P. node" with "Combine X.." as a way to correct space. Essentially you mapped that wave texture to the X... then told spiral to be off set on the Z  based on the X mapping? I checked Blender Doc. and it says if vector is left unplugged it defaults " Generated Texture  coordinate"... which I think broke mine.

Ah, Okay I see now. You ref. the spline it's self (using factor 0-1 of spline),  where as before I was actually ref. the object I initially used to create the system in the first place.... So you told blender " Hey sin X of this spline ( our spiral), then off set the spiral on the Z axis- based on sin X (wave texture) of that same spline... very cool. So it's kind of like you created your own space for the spline... Thanks again.  Explaining the actual function of wave texture- and what it was being applied to helped a lot.


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Magic Eye Render

Today's newspaper had a Magic Eye or Autostereogram image in the kids section
... started me wondering could tools available to blender,  be used to render a simple scene (Suzanne of course, repeating grease pencil Suzanne) as a  Magic Eye?

Image and python code from Saving Autostereograms AKA Magic Eyes Albeit explaining finding the 3d object from image.
Another python generator here magicpy which takes a greyscale bitmap as input. Which could be used in post-pro.

I reckon it’s feasible. Obviously just coding it in python and outputting an image is somewhat cheating... so either compositor or perhaps a shader with some image feedback would work.

FWIW That's my gut feeling too. ... but my knowledge of howto is very  limited --->  resorting to cheating.

It’s essentially just a horizontal clone based on depth at that point (I developed one in C many many years ago as part of a uni project). The tricky bit will be repeating it as you need to recursively cover the whole image. I reckon a node group in the compositor simply repeated a few times should do it.

Managed to get a basic setup working in the compositor as a proof of concept. Here's the link : https://imgur.com/a/OzO3sql  I'll write a proper answer and explanation shortly.

You are a legend.  Did imgur crash last night,? tried 4 times to put in the animated shark from wiki.

I was like obsessed with these as a kid.

Remember people staring at framed versions in shopping centres. Thought they had some  weird taste in art.. (like who knows with some of it?) , until I  finally twigged  as to what they were seeing.

I didn't have a problem with imgur - the problem must have been fixed when I tried. I remember standing in a shop looking at an image and wondering what all the fuss was about and then having the realisation that there's something there and being able to see it. I'm in the process of putting tother an answer for this.... struggling with the explanation and making it understandable!

Remember shopping?

A "Magic Eye" image encodes the depth information into the repeating horizontal pattern such that "going cross-eyed" and matching up adjacent copies of the image fools our eyes into interpreting it as "depth". This can be demonstrated by looking at the following image :

Look at the central image. Relax your eyes so that you're looking "through" the screen so that one eye is focussing on the middle one but the image of the left or right-hand one (which one you find easier will probably depend on your "dominant" eye) crosses over to coincide with the middle one and you should see 4 monkey heads (you may need to position your head closer or further from the screen for this one). This is essentially what you need to do with a "Magic Eye" picture - but with the repeating pattern coinciding with the adjacent almost identical clone of the pattern. Note that for this to work your head must be aligned left-right to the horizontal of the image.
The same principle is behind a full "Magic Eye" image - where two adjacent and almost identical sections of the pattern coincide from both eyes to fool your brain to perceive depth. This is achieved by using a 'seed' texture at one side of the image and cloning it across the page based on the 'depth' of the original rendering at that point. The wider the spacing between 'clones', the further 'into' the page the surface will appear. We can achieve this in the compositor by using the Depth information from the render to control the offset of a Displace operation to clone the seed texture across the image.
Start by generating the 'seed' texture. This can be any image but it needs to have enough contrast and detail. One edge of it will be used to clone and repeat over the final image to produce the effect (depending on which direction we're going to clone left-right or right-left). The distance between copies will fool the eye into seeing the depth at that point. For my initial renderings I simply used a Distorted Noise texture as shown :

The clone is achieved by using the Depth at each point in the render to displace the texture and using Alpha Over to combine with the previous image (so that it's a clone rather than just displacement). Note that anything outside the bounds of the image will be ignored (transparent) so that we don't copy from outside the image boundary over our seed. Everywhere else we'll get the texture displaced based on the distance at that point - so it will be a clone of the seed horizontally in the image.

Note the inputs of the groups are passed out to the outputs. This will allow multiple instances of the clone to be easily chained together.
Connect the clone up to the texture along with some nodes to adjust the raw Depth values to a suitable displacement distance. Note that smaller displacements will make for a "flatter" final result.

By repeating the 'clone' group mulitple times we effectively clone to each subsequent 'band' of repetitions of the seed. This can be visualised by taking a snapshot of the result at each stage along the chain :

Note how the initial 'seed' is cloned to create the first 'band' in the first frame and each subsequent stage leaves the left-hand region unaffected (since that's already a displaced clone of the section to the left, according to the depth map) and adds on the next 'band' which was previously just a displaced copy of the entire seed texture.
If there aren't enough bands to reach all the way across the image there will be "flat" regions on the far side - link in more copies of the 'Clone' group to resolve this (although the more 'Clone' operations you add, the more work the compositor will need to do to complete the render). The number of required iterations depends on the size of your Multiplier - larger values fill the image quicker by having a wider spacing (and so larger apparent depth). Smaller values give a shallower image but need more iterations since the bands are narrower and so closer together (meaning you need more of them to span the whole page).

Note that the Depth of the original render is Normalized so as to range from 0.0 to 1.0 and an offset (in this case 1.0) added to give a minimum spacing.
This produces the following result :

Any 'seed' image can be used - the only requirement is that it is varied and contains small and distinguishable details. I experimented with a family of monkeys as I thought that would be most appropriate :

Blend file included

Instructions unclear. My bedroom is now inside-out.

Sorry about that @Robin. I should have included a disclaimer :-D

Can't wait to test this out. Cooked my GPU, am currently (& surprisingly) running on blender on an old  Nvidia 220 ... chokes on this.

@RichSedman, you, Omar Emara and others have inspired my interest in mathematics. I am over a year self-studying maths and physics as a hobby.

This is really amazing! thank you so much for sharing! I would have expected waaaay more upvotes for this, maybe because only a few people can see the result :D


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Cloth simulation doesn't work for particular object
I'm trying to follow this tutorial: https://www.youtube.com/watch?v=1bGB-EePxWI
But when I apply the cloth modifier and playback, the object doesn't drop as it generally would
I'm pressing playback in object mode; The simulation works correctly for a new object, but not the one I edited
No pinning. I'm trying to simulate a free-fall
Blender v2.82a

For any newbie in the future, just check you are in object mode before run the scenario.

I had the same problem. Took me over half an hour to figure out.
The problem is caused by duplicated vertices.
To fix it switch to edit mode.
Press Alt + H to make sure there is nothing hidden. Then select all vertices A and then press M to merge them by distance.
Have a look at the status bar: 148 vertices removed. Switch back to object mode. Play the simulation. It works again.

Just wow, I grew very very angry at Blender :D Thanks for the great tip!

I just had this problem. Blender would go through the motions of baking the cloth simulator but I couldn't get past "0 files on disk" or "0 files in memory."
For me, the answer was that I had disabled the cloth object in the outliner. I was also fighting with keyframing visibility in Object Properties too - it's a long scene and I don't want to expose it (and slow down renders) before it's "in the frame."
But in my case - there were no dupe or loose vertices... and toggling on the little eye or camera in outliner solved it. I'm not sure in hindsight how I was seeing it in the viewport - it could have been on the collection as well..

You might want to double check the physics properties of the object. Also you may want to try duplicating the object, or restarting Blender. Also, and I'm not sure about this, but if your object is instanced it may not be possible. Check the data and see if it's in use by more than one object.

Pressing playback is not a good way to review the cloth simulation. You need to let the computer calculate the equations and mathematical things for the cloth so that you can see them correctly. You do this for the first time only and then you will be able to playback because the baking process results can be saved on your hard drive.
How to bake cloth simulation:

Select your cloth in object mode.
Go to the physics settings (By clicking on the physics tab).
Expand the "Cache" section.
Set the frames where you need to start and end your simulation.
(Optional) uncheck "Use Library Path" and check "External" to save it in a specific or known location on your hard drive.
Click on Bake button and let your computer take its time.

Further work:
What if you don't like to edit your cloth after you baked it? You can simply click on "Free bake" then, you can edit your mesh (cloth) and then rebake using the previous steps.

this does not solve his problem (sadly)

I did try baking. Did not work
As I said, it works for other objects in my scene without any extra steps. Don't know what makes this object different


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Presence of a strip on another NLA track prevents execution of original track
Using the default cube, create a keyframe at frame 1 where y=-4 and a keyframe at frame 40 where y=4.

Change the action just created to an NLA strip on a new NLA track.

With the current frame=20, Use the NLA editor to split the NLA strip in half via Edit>Split Strips. Drag the 2nd half to frames 40-60.

At this point, playing the animation will result in the cube moving from y=-4 to y=0, remaining stationary between frames 20 & 40 and then from frame 40 onward continuing from y=0 to y=4.
I now add a new action between frames 20 & 40 that rotates by 90 degrees and add it as an NLA strip.
If all 3 NLA strips reside on the same NLA track, the animation now plays as expected. Translation, rotation, translation.

However, if the rotation strip is moved to it's own NLA track, this changes.

In this situation, there is
translation from frames 0-20,
rotation from frames 20-40 but
nothing from frames 40-60
The presence of the rotation strip between 20-40 prevents the 2nd part of the translation from occuring.
In the NLA right panel, I've tried all the various Extrapolation combinations for all 3 NLA strips.
What am I doing wrong here here?
Blender v2.83.3 on Linux

I haven't read everything but have you tried to select your top strip and in the NLA right panel (press N to display) > Active Strip > Extrapolation > Choose Nothing instead of Hold

Thanks moonboots. Was unaware of those options, but have now tried them all & amended the question.


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Create refocus effect for a image?
I have got this image:

The idea is seperate the image to two using mask in U/V image editor, then blur each one to make it look like the camera changes its focus from the man to the ipod:

I've got the mask. But how I do that in node editor?
Blend file:

Ok I got it here. It's hard to do this in only blender. Using photoshop would simplify this..
    The idea is simple. Open photoshop (or GIMP whatever..) => load the image in => Cut it into two (Each one has a focal point, near and further) => Export them as PNG => Load the two images into Blender => Composite them, blur each one at a time to fake this defocusing effect!


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Objects behind glass appear too dark

It's so dark that the eyes are invisible.
Blend file:

The blendfile is different to the one in the pictures. Was this done on purpose?

Oh really? Don't remember I made any changes to this after writing the question. Does it matter much?

Sorry guys. Just reupload it! Have a look. Pls!

The file's being kind of glitchy and the goggles aren't even showing up in the viewport for me. Since the material is just glass and glossy it means it's getting it's colour from it's environment so it could be the lighting that is making it look dark. Maybe try lighting up the world?

Oh my just turn its visibilty on, man! I suppose lighting up the world wouldnt help....

The glass has no no thickness. No back faces. So the light enters the surface and for the ray the thickness is infinity. Make the goggles from 2 pieces and model the lenses properly.

So.. what do you mean by modeling the lenses "properly"?

Could you please be sure of what you are talking about?

#Jerryno Dont ever talk something as if you are absolutely right

@thododo You're the one here asking for help. Try not to be rude.

There's something really strange about your file, I can't select the character or the goggles at all and they don't show up in the outliner.  But it does look like jerryno is right, you need to give the glass some thickness.

@PGmath For me the goggles are hidden, but visible in the outliner (they're named goggles.002) with selectability is disabled (along with a number of other objects).

@gandalf3 How do you disable selectability (I unhid everything)?

Sorry just that I was so frustrated! :( What jerrno said was definitely not the correct solution. I just didnt want to waste time on that. I just found the answer myself. Turning on reflective caustics helped.

Sorry jerryno for rudeness again and thanks guys

@PGmath Click the mouse icon in the outliner

@gandalf3 Thanks, I never knew you could do that in Blender!

english is not my first language and by model "properly" I didn't meant to offend your modeling skills, I am sorry.

No need for you to say sorry. I am the one who do. That's ok now

There are several things causing this:

Lenses have no thickness (as pointed out by Jerryno)
Rendering caustics is hard

Lens geometry
In the real world the lenses are likely solid objects separate from the goggles, merely fastened into place within the goggle frames by some means.
So model virtual lenses separately and put them in the virtual goggle frames:

Start by making the goggle frames solid on their own, without any lenses:

Then model a separate lens mesh and put it in the frame. It shouldn't be connected to the frame (if you hover over it and press L, it and only it should be selected):

Ensure that the eye mesh doesn't intersect the lens:

Caustics
Even with all that, a normal glass shader will still likely look dark without lots of samples. This is due to the fact that the only way for light to get behind and illuminate the eyes is by refracting through the lenses then reflecting back out, which is a fairly unlikely path for a ray to take.  See this question for more detail.
To work around this, use a setup like the one described in How to illuminate the darkness inside glass objects in Cycles?:

Thanks! How to lighten up object behind glass is definitely what I am looking for

Can I ask you about your lighting? It looks sooo nice!! Couldnt think my work can look this nice

@thododo The fact is I didn't touch anything. I simply enabled the existing light sources in your file; the lighting is all you :)


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how do i mimic SketchUp navigation settings in blender 2.8?
I've learned cad from Sketchup and find navigating in it pretty easy and so I want to switch to blender and want to keep navigating like that it'll make it way easier to transition. there's another question similar to this but the whole blender settings panel has changed since then.
It'd be amazing if someone can help me do this in blender 2.8 and later versions please provide screenshots if possible. all help is appreciated.

Can you please provide more info, for example, please record what you mean about the navigation? In the 3D viewport, If you go to View > Navigation > Walk/Fly Navigation then you can use the WDSA keys to move, if that's not what you mean, please explain in more depth about it.

Does this answer help? https://blender.stackexchange.com/questions/81715/mimic-navigation-in-sketchup-c4d

In SketchUp when you zoom in using your mouse wheel it magnifies/zooms where the cursor is present whereas, in the case of blender the position of the cursor doesn't matter it is always zoomed to the centre of the screen, the situation is similar for orbit / rotate. If possible try SketchUp for a brief movement to understand what I mean. the navigation system provided  in SketchUp is way more flexible and doesn't restrict you the centre of the screen


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viewport render has better anti-aliasing than output render

This screen grab has my viewport render on the left and output on the right. Can anyone help me solve why my lines are so poor on the output image?
this is a 3d model with a grease pencil outline and I'm rendering with cycles

What resolution are you rendering at?

We could use a screen shot of your render settings but I suspect @James question is the key.  That looks like a very low resolution render.

You're 100% correct. it was a low res render. Thanks for the help


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How to contain particles within object?
this may be a stupid question, but I only really use blender casually and I need some help for a project. I'm doing a thing where I want to have rose petals flying around in an animation, so I'm using a particle system emitting rose petals. However, when I set the particles to fly around (I have them flying around using Brownian and the gravity set to 0), by the end of the animation, they are all flying outwards when I want them to stay within a certain boundary. I've scoured through every single option the particle tab has to offer, looked through dozens of tutorials, but none of them seem to solve the problem. I know there is a way to contain particles within an object, such as a cube, but I just haven't been able to find how. It is worth noting that I have tried emitting particles via both a plane and a cube, just to see if i could make it work both ways, however both have failed.

If you want them to stay within a boundary... have you created a boundary or how should the particles know where the boundary is? Maybe a plane with collision on it? The problem is, all the settings in the Particles Tab are for emitting the particles. To stop them you need external obstacles (or just let them die by setting a short lifetime).

i've tried adding planes with collision stuff on there, but it always causes a lot of glitches with how they work. i tried a cube but it just caused them all to stick to each other and stick to the edges of the cube.

Just duplicate your original object and for the duplicated object:

Remove its particle system(particle system also duplicates while duplicating an object)
Go to Physics Properties, and click on Collision
Select your original object and bake the particle system
Delete the duplicated object

This just makes my rose petals go completely everywhere and glitch out. When I try it with the cube, it causes the petals to glitch to the sides of the cube, and when I try it with the plane, it kinda works but a copy of the petals all fall down and continue to fall, while there is still no boundaries.

Can you provide your .blend file? https://blend-exchange.com


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Best way to resample/re-mesh portion of the screwed up mesh?
I've end up with this mesh. You can see it has vertices that connected to many edges in a star formation. It causes those faces to stick out and making sculpting harder.
I am looking for a way to re-mesh those regions with some more uniformal pattern, so I can smooth it out in sculpting.
Alternatively I was imagining some method of sculpting AND adding more details at the same time.

In the end Iv'e used combination of methods. I think it would be sufficient for me to use only one - Dyntopo while sculpting. This video was very helpful in understanding how it works: https://www.youtube.com/watch?v=8FTRK5uo6T0&ab_channel=SirPinkBeard
In my case I've already worked on UV and so, I had to learn another thing - Data Transfer modifier, which allowed me to transfer my UV stuff into a new mesh.


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Alpha Over node doesn't work correctly?
Here's the first output:

The second:

And after using Alpha Over node:

Blend file:

Check the Convert Premul option.

Could you please add some more information, maybe explain what convert premul does?

@PGmath I actually have asked that question myself. From cegaton's comment there I was able to understand it better, but I don't feel I can explain it well. I hammered out this answer here in a span of a few minutes while on a short train ride, hoping to at least solve OP's problem even if I couldn't elaborate. Feel free to add something to the answer if you like.


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Can't unwrap new geometry added to the already unwraped object!
I unwraped the object, added texture to it. But now I'd like to add some more detail the object. Tried to select only the new geometry and select "Smart unwraped" but the work of unwraping it didnt show in UV image editor.
Here's blend. file:

You didn't pack the texture with the file so I wasn't able to check where they were assigned to...
...anyway, by unchecking the UV local view box, you should be able to Unwrap and see the faces.

That option is not well integrated in Cycles, while it is often useful in Blender Render. Developers talk about it in this review.


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Assigning two shortcuts for the same action
I'd like to assign two shortcuts to the undo action in blender 2.8 (ctr+z and middle mouse click) but I failed as it seems only one at time is possible. Is there any way to do so?

Please consider using the latest Long-Term-Support stable version of blender i.e., 2.83.1 (which will be supported for 2 years, without major feature change).

There is a way, but it's a very bad idea
You should not do it. Middle click is used too much to practically change it and retain important functionality in Blender's keymaps.
You would have to add a new entry here in the Preferences(F4 -> P), Keymap tab, under Screen, Screen(Global):

But you would also have to search for and remove all the conflicts:

That would break stuff.
This would be a very bad idea.


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How to make a shadow catcher be able to see things behind it?
I am using blender 2.83. I am trying to make a shadow catcher. But it needs to be able to see an Image behind it when I render it. Here is an image:

I need to yellow part to be able to see the image behind it. But It still be a shadow catcher.
If someone could tell me how to do this. That would be great!
Here is the link to the .Blend file:
https://drive.google.com/file/d/1lxsJGJdQFgZ1aWXAy_etywFz-zV8I5s2/view?usp=sharing

Are you using an image as it's own textured object behind your shadow catcher?

I used the images as planes addon to import the image


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How long should the Blender BMW demo file take to render?
This is a different question. But I didn’t know where else I should have asked.
I tried rendering the Blender BMW demo file (in cycles, with GPU) and the render took 37 minutes and 48 seconds.
The i tried using CPU instead, and it took 18 minutes.
Is that a very slow render time. If it is, what is considered a “good” render time?
If it is slow, how can I make it faster besides rendering in smaller dimensions and the obvious stuff?

For reference - On my hardware (CPU: Ryzen3950x - GPU: RTX 2080Ti) CPU render took ~1:46 and GPU Compute took ~6:03 (Though GPU usage never exceeded 10%).

My PC also needed about 16 min for CPU rendering (8x 64x64px tiles) and the onboard GPU is not supported. More render benchmarks for comparison can be found here: https://opendata.blender.org/

It depends on your hardware. The BMW "blenchmark" should take however long it takes to render without you modifying the file.
The idea of such benchmark is for folks to see how their particular hardware compares to other in similar circumstances, with the same scene with the exact same settings.
The results are here:
http://blenchmark.com/gpu-benchmarks

Are there ways to speed it up? yes, but that is not the point of said file.
If everybody modifies the file, then there will be way too many variables and the statistics and comparisons for rendering are no longer valid.


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How do I select multiple items in the outliner or file browser without selecting all the items in between?
When I try to append multiple files at once, or when I try to select multiple objects in the outliner window that aren't right on top of each other, every file or object between the ones I select are selected as well, and there is no way to un-select them and choose the files I want.
To combat this, I've been using the drag and drop feature when I can, and other times, I append or select the objects one by one or in the viewport. Sometimes, in the outliner, I can make collections invisible, but that doesn't work if I have multiple items in multiple collections. It's annoying because I've always been able to just select whatever I needed and get it done in every other version of blender except this one, and turning on an old laptop to work on some blender files lately in v2.69 reminded me of just how much many new minor changes in 2.81 have slowed down my workflow.
Is there any way to change this?

Isn't selecting several non-continous items in Outliner and File Browser done with Shift+clicking on the items one by one? Box Select will select everything box covers as always

Outliner and File browser is Ctrl + Click

Right, this behaviour was changed as of 2.81 I think and Ctrl together with Shift now work according to other existing file browsers out there

It seems like you are trying to Select the different Objects withShift+Click.
Try to use Ctrl+Click on the different Objects to select multiple Objects.

Ctrl+Click worked. Thank you Mr Zak, Emir, Ray Mairlot, susu and pr1mus. You have all been a huge help.


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Why is the transparency on my particles not working once exported to Godot?
I am new to blender. I am using blender 2.8 version. Recently I created a grass setup with the help of a tutorial video. In which I applied transparency for outside of grass using node editor. It renders completely fine. But if I export it to Godot, the meshes and materials exported perfectly. But the transparency from node editor is not applied. So instead of seeing a grass, all I see is a plane with grass image. I added the screenshots for your reference.

This is more of a Godot question than a Blender question, so this question is likely to be closed for being off topic. Before that happens, though, have you enabled "Use Alpha Scissor" and played with the slider under the parameters tab of your material in Godot?

From what I've found Godot uses the alpha value of the albedo color as transparency.
A blender material with transparency enabled and the alpha value changed looks right in Blender, but doesn't work in Godot:

As you see, it correctly turned on the "Transparent" flag, but still has no alpha.
You have to change the alpha value of the albedo color in the Blender material for it to work:


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Move camera depth of field from background to magnifier on the foreground
I have a shot here where I would like to move the focus from the background to the magnifier on the foreground.
Maybe I'm wrong here, but tell me, when the focus is on the foreground, the reflection on the magnifier (the zoomed image) should be sharper, no ?
Because on my example below, the reflection is as blurred as the background.
Am I doing something wrong ?

Thanks

This is actually as expected - the 'image' through the magnifying will not be focussed at the distance of the magnifying glass but will actually be focussed at a distance dependent on the distance to the magnifying glass and the focal length of the lens - and this wont correspond with the actual distance of the distant object.
Since the focal distance of the image doesn't correspond to any "physical" object in the scene you will need to manually adjust the Depth of Field distance to find the required focal depth - simply adjust it until you get a sharp image. Note that you may need to adjust it well beyond the distance to the object, making the magnifying glass itself even more out of focus!


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Change the color of the default (no) material (Cycles)
In the idea of having a faster workflow, I would like to know if it is possible to change the color of the default (no) material of Cycles.
I mean, if you don't assign an material to an object, it is by default a diffuse material that is light grey (0.8 white).
I like to have my objects having that default light grey because then I can give certain meshes more emphasis simply by assigning them a pure white material; which give the scene some contrast.
How could I change the color of that default light grey so I could darken it and accentuate the contrast ?
The idea being to be able to do this using no materials (default color), because assigning ALL meshes a material would be too long in my work process.
Actually I use a light to make my subject more bright.  But this has a lot of inconvenients, that is why I ask !
Thanks!

The default material is hardcoded as far as I can tell. "Because assigning ALL meshes a material would be too long" Select all Ctrl+L> Link Materials. How is that too long? you then get all the control you like

You would need to build your own custom build of blender to change what blender uses when there are no materials. Setting the material override in render layers is a way to use one material for everything.

@DuarteFarrajotaRamos thanks for those precisions.  Is it possible to better select all meshes that don't have any materials set ?

Open Blender, go to the Materials tab from the drop down select Material. Make your required changes, you code enable Nodes and do something really complex or just change the colour. Then go to the File menu and Save Startup File.

Now when you open Blender the default material will be your custom one.
You can also do this to have a default background.

Alternatively, you can set a single material for all objects from the Render Layers tab. Handy for Clay renders.


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Scene lighting and setup: how would you get such a render?
Just for fun, i'm trying to recreate a scene from the (nice) movie Cherry 2000.  Here's a link to the clip.

I like the aesthetic, but I can't figure out how they did setup their scene; and that's what I would like to understand.
Would it be possible to recreate something similar with Blender ?
There is a woman, a red spot, and... a metallic curtain ? Is this a metallic curtain for the shadows to be distorted like this ?

How did they do to have the shadow so sharpened ?
Where is placed the lady compared to the camera ?  And is she behind the curtain ?  Then it couldn't be a metallic curtain ?
How did they lighten the scene ? The more "metallic" my curtain is, the more narrow the light "slice" I get.

Well, i'm sure I could learn more things about materials and lighting by understanding this.
Your input is welcome! I have nothing convincing yet but I can share my actual file so you can play with the curtain : the file is here.

And here's a test with Suzanne between the camera and the curtain - but that's cheating; I did hide the object from cycles so i get only its shadow (Ray Visibility)

Yes, but in this case, I should not need to cheat.  There must be a way to recreate the same setup....