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Get camera location/angle from viewport in scripting
Blender 3.3, I'm going to use scripting to adjust the location of my camera for a render so I'd like to try out a few camera positions and angles. I want to scroll around a viewport to get the right view and then determine the viewport's camera's location and angle so I can set the camera used for rendering to those values later.
But I can't work out what scripting call to make to get the view location/angle from the current viewport. Anyone assist?

I never found out how to do this, but as a compromise I have scrolled the viewport to the view I want and used Ctrl-Alt-Num0 which moves the camera to that view, so I can then read the location and angle from the camera.
I'm sure somewhere in the object model is the location and angle of the viewport onto the view, but there's too big a data tree for me to find it directly so this compromise will do.


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Blender camera sensor size physical equivalent?
I am confused because when it comes to real cameras their sensor sizes are defined by two numbers that represent the x and y dimensions of their orthogonal camera sensor. Why is blender only using one sensor size parameter and not one for the x and one for the y dimension of the camera sensor? What is blender's single sensor size parameter representing physically about the camera sensor? Is it the sensor's diagonal dimension?

The render camera in Blender is a virtual camera, so usually it is not related to the sensor size settings. For example, the camera in Blender is a infinitely small single point in the scene, with no dimensions for sensor or the lens etc.  - but saying there is no relation between them would be to simple as an answer.
First of all, you can use the Sensor Fit to decide how the rendered image should be placed in a real camera's photo, and you can use the sensor size to recreate something like the crop factor of real cameras for example.
The Focal Length you set in the (virtual) Lens properties is usually calculated upon the assumption that you have a full format camera. Just like in real life, where the focal length of lenses commonly is given in relation to full format sensors.
Which means, if you place the virtual camera in a certain distance to an object, it will appear as large in the rendered image as these things would appear if they were all in real-life dimensions and you would take a picture with a full format camera with a lens of the given focal length. This is based on a theoretical full format sensor size of 36 × 24 mm (real sensors of course might slightly vary in their size).
But instead of a real camera which often has sensor aspect ratios of 3:2 or 4:3, the rendered image only cares for the image size given in the Output Properties, so by default 1920 × 1080 pixels or aspect ratio of 16:9 which means this default full format sensor size is more or less irrelevant for rendering.
Now the Camera setting Sensor Fit at the default Auto with a Size of 36 mm is showing (if you enable Sensor in the Viewport Display options of the camera) a square frame if you look through the camera which is made to fit always the largest dimension of the render border:

I've placed the cubes so that they fill the image from left to right. Using the default Auto and Size_ 36 mm means, the width of the square simulates how much the real full format camera sensor would see (in width) from the cubes with a 50 mm lens at this distance. The aspect ratio of a real sensor is ignored here, therefore the square. The virtual camera's width is the same as the sensor width, but as mentioned before, the aspect ratio 16:9 is determined by the render dimensions only.
What happens now if you switch from Auto to Horizontal is that you can enter values for Width and Height instead of a single value. By default it will be 36 × 24 mm, the standard full format sensor size. This means, the frame displaying the sensor in the viewport is no longer square, but rectangular and has an aspect ratio of 3:2, it still fits the width of the sensor frame to the render border and no matter what Height you set, the width will stay the same in the viewport - horizontally.
As you can see, the frame is still showing the cubes fit from left to right and for the next demonstration I had placed them so that they now fill the sensor frame from top to bottom:

But have a look what happens if you switch now Sensor Fit to Vertical. In this case, Blender will fit the height of the sensor frame into the render border, so no matter which width you set, the frame will vertically keep its size. However, it  looks as if Blender's virtual camera has zoomed out - which it did. The cubes still fill the sensor frame from left to right and top to bottom, but since the render aspect ratio  is 16:9, the camera had to zoom to fit it in vertically:

So by saying the Sensor Fit should be other than Auto, you can determine how a rendered image should be placed inside the sensor frame: either horizontally, which results in a rendered 16:9 image that is cropped at the top and bottom compared to a real-life photo at 3:2, or you make it fit vertically, which results in a rendered 16:9 image which is expanded to the left and right compared to a real-life photo at 3:2.

Which already brings us close to recreating the crop factor of a not full format camera. Since you asked about sensor fit and real-life dimensions etc. I guess you know what a crop factor is (possibly better than I do), so just in short and simplified: when a camera has a smaller sensor than roundabout 36 × 24 mm, and image  covers more of the sensor at the same focal length, which means a photo taken with the smaller sensor appears larger, as if the lens had a greater focal length than the given one. The crop factor is the multiplier how much larger an image appears, so for e.g. a Canon APS-C camera with a sensor size of 22.3 × 14.9 mm the crop factor is 1.61 roundabout.
This means, the 50 mm lens on the APS-C camera takes photos as if they were taken with a full format camera and a 50 mm × 1.61 = 80.5 mm lens (don't lapidate me, this is all very simplified). To simulate this with the default camera settings in Blender like Sensor Fit > Auto and Size 36 mm, you could simply enter 80.5 mm as Focal Length value.
Or you use real-life values - if you know you have a 50 mm lens and know the dimensions of the sensor, you can set Sensor Fit to Horizontal and enter the real Width and Height. The resulting rendered image will be the same size... more or less, since neither 36/22.3 nor 24/14.9 is exactly 1.61 but you get the idea:

Amazing answer! Thank you very much.

source: Stack Exchange

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

sort: votes


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Change 'Image Sequence' images, visualize in Image Editor, save after changes
I add a plane in Blender. Then in Shader mode I create Image Texture Node and set 'Image Sequence'. This displays the texture to the plane which can be changed by keyboard <- and ->. Also, I can visualize the image texture in Image Editor. This everything works fine. If I do some changes in Paint mode, it appears in both.
The problem is when I want to have colorful texture and add ColorRamp. In object mode, it looks good. Everything is colorful. But in Image Editor, the image is still grayscale. Do you have any idea how to achieve the colorful image also in Image Editor? Also I want to save newly changed images, but not sure how.

Please do you have any advices? Thank you very much. Sorry, I am beginner.

Hello ! What you're looking for is texture baking, but you can't do it real-time I'm afraid. The flow of information here is top right editor (input map) > bottom right (pixel shader) > left (viewport shading). And it can't flow the other way around

Interesting ... For a single image Blender warns you about unsaved images (and automatically is set to save them) ... but that is not happening for image sequence, hmm ...
You would have to save them manually under Image Editor > Properties > Image > Save ... each individually (in case we are speaking about manually painted images).

About saving as coloured ... as suggested by Gorgious ... use Bake (switch to Cycles, plug ColorRamp directly to Output node and switch Bake Type to Emit

For baking sequence check this addon. Ad a new Image Texture node with new Image, Save image and with node still selected (Active) press Animated Bake.
Even written for 2.8, worked for me under 3.5 ...

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


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How to make curved (upturned) roof?
I'm trying to make a traditional Asian roof, and it's corners should be upturned (as showing in the reference image). I made arrays of cylinders. Then I tried using proportional editing with falloff. Also tried using lattice modifier. They all have a problem, that is, they all change the shape of each roof tile at the corners real bad. The cylinders at corners no longer look like cylinder they're all heavily stretched and not symmetrical. Even the smoothing gets ruined. But in real life each roof tile is of the same shape and symmetrical. They form the curved roof by rotating instead of stretching their shapes. So how to make curved roof in a more precise way please?

https://blender.stackexchange.com/questions/21448/how-to-avoid-objects-intersecting-eachother

@batFINGER It looks similar but following that method only gives a curved overall shape like using Simple Deform modifier with setting to "bend". it couldn't give the corners upturned shape.


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Extrude in curves
Inside Curve Properties there's a Extrude option that creates faces along a curve. When use free handles to make a sharp angle the faces around the free handles have ununified shape like shown below. I find the same problem in Solidify modifier that with Even Thickness off the shape around the sharp angle looks bad and with Even Thickness on it looks good. It's because without even thickness each vertex will extrude the same distance whereas sometimes some vertex(for instance the vertex that forms a sharp angle) needs to extrude longer to make the overall shape unified. So is there a way to achieve the same result for curves like even thickness in Solidify?

I think that is blender limitation, but there is another way to achive that
you can extrude in curve property as thin as possible,

then add Solidify modifier and check even thickness, you may add Weld modifier to keep one side surface in case you dont need double sided (solidified surface),

Here the result

Thank you, this works like a charm, in my case I need to set the curve points 90 degrees tilt. The only pity is that the Bevel-Depth of curve properties no longer works correctly with it since the curve has a Solidify modifier. But it's already very good, thank you very much.

Hi, if i understand you may add solidify again after weld modifier and then add bevel modifier i think it will get similar result.
also, if this answer you looking for, please consider to mark answer accepted

Yes, with a bevel modifier it would have similar result and thank you again for your kind help


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How to reopen the panel that shows when creating objects?
When creating objects a panel shows on the left bottom side, like this.

And sometimes I click other objects or hit Tab going to edit mode then realize I need to tweak some properties on that panel. But it's already gone. Is there any way to bring it back? Thanks in advance.

you can do this with F9.
But whenever you do something else in between - e.g. move another object - it is gone. Then you cannot call it again.

Ok, thanks. I think I can understand this panel no longer accessible if the mesh data has changed. For instance, you moved some vertices of the sphere or you even sculpt it. Then the original properties of that panel such as segments and rings are no longer useful since it's not a serious sphere anymore. I guess that's the reason why the maker makes this way. But selecting between objects or toggle between edit mode and object mode(doing noting) don't really change the mesh data. This panel is still useful for them. Anyway I wish this feature will be improved in the future


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Find out by how many shortest path curves a vertex is used
I'm using Geometry Nodes Shortes Edge Paths + Edge Paths to Curves to create some guide curves for a hair model. On the source mesh I have end points on the outer border only while all other vertices are starting points. That results in many vertices are used by several curves. That is fine but it would be extremely helpful for the next step if it would be possible to find out for each vertex (more precisely: for each curve's root) by how many shortest edge paths it has been used (this would help to reduce hair density in some parts where it has no or very little visual effect).
I don't see how this could work, but would be very happy if someone could prove me wrong and show me a solution. Ah, and it has to be fast, because the number of guide curves created is already quite high.
BTW: I'm using 4.0.0 alpha already because a bug in 3.6.x, which so far is only fixed there, forces me to do so.

Updated:
While looking at it again after a while I found out that it is actually possible to achieve exactly what I wanted. It works as follows:

For each point (vertex) of the original mesh capture its index
Create the shortest path curves (many points are used by several splines)
Convert to points (Curves to Points with method Evaluated)
Use the new Points to Curves (Blender 4.0.0) node to sort points according to the original mesh vertex index (captured above)
Capture the new point index for each control point
Use Delete Geometry (or Separate Geometry) to delete every control point

if the next point (index+1) belongs to the same original mesh vertex
and in a second copy if the previous point (index-1) belongs to the same original mesh vertex

Now we have two curves with exactly one control point for each original mesh vertex in the same order as in the original mesh
For each vertex of the original mesh we can calculate the number of curves using that point by the difference between the lowest and highest index (from step 6.)

If it is not guaranteed that all vertices are actually used by at least one spline, then all original mesh vertices can be joined in the points created in step 3. by Join Geometry (afterwards such points need special treatment to avoid counting them as 1 spline using that vertex).
In my case I want to find the point which is used by the least other curves for each curve. That can be done by

Another sorting run (Points to Curves) such that we get one curve per original curve with all its original points but this time sorted by the number of curves using each point (from the previous step)
By deleting all but the point used by the smallest number of curves (which is the last point of each curve if sorted in descending order), we get again one point per curve with the value we are interested in
In my case I take that for curves derived from the curves used above (but resampled, such that they have other control points)

Example: I'm using that to create more hair curves especially next to the parting area by using the value calculated above to create the Amount input field for a Duplicate Hair Curves node.

It might be possible to simplify that by using the new Repeat Zone but I did not try that yet.


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I'd like to texture paint to different objects that have same photo texture. However, when I paint one thing, it effects to other objects too
I'd like to texture paint to different objects that have same photo texture. However, when I paint one thing, it effects to other objects too.

so when I tried to paint one single object, it also effects to other object that shares the same image texture. I already cut the number? thing in shader but its not working.

What are you using for mapping the Image Texture - UV unwrapped or are you using as a square box map blended image? If you have UV overlapping, this happens. I go through steps to get there first by using the box mapping image to bake to a new blank image that has my ideal uv so that I can then paint that result saved image or combine with yet another and use a stencil between.

You need to understand that when you are texture painting, you are actually painting on the image and since you are modifying the image, it's going to appear in every object that you use that image on :

And it will be like this even if you use different materials for the objects.
If you want to get around this, you need to make a copy of the image for each object :
Go to an Image Editor window  :

The 2 that you see near the image name indicates the number of users of this image. That means that if you make modifications to that image, 2 "things" would be affected by those modifications. I said "things" here because it can be an object, a material or something else. In my case it's the materials used by the Cube and the Sphere :

Click on that little 2 and you'll create a duplicate of the image (don't forget to save the image first either externally or by packing it inside of the blend file) :

Now you have two images that are identical but the Cube and the Sphere are still using the original one. To change that, I can just go to the Shading workspace and select, say, the Cube and make it use the new image image.001 :

Now I can paint on the Cube without affecting the Sphere :


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Rigacar/Rigify Tab gone
I once was able to see the rigacar tab with all the other tabs in my viewport (the ones by the navigation, that little sidebar that slides in and out with N, but it seems to be gone. Maybe after an update? Anyone else having this issue figure it out yet? It's not that I haven't enabled it in preferences, I've have had it enabled for a while now, it just seems to have disappeared and no option anywhere to enable it again. I'm trying to follow along with a car animation tutorial that uses rigacar and I cannot use mine for whatever reason even tho I can see some of the options in the property tabs underneath the outliner, but no rigacar tab. Im trying to get the wheels to move with the car on the path without having to animate the keyframes, I mean isn't that mostly the reason why we want to use rigacar anyhow?

Go to the Scripting tab or create a text editor window, from its dropdown menu select the text file named as your rig followed by _ui.py, then press the play button to execute the script.


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Addons Do Not Show Up in User Preferences
I have installed many addons in the past with no problem. However, after reinstalling Blender, it no longer detects the custom addons in the user preferences at all.

I have used the manual "Install" button available in user preferences.
I have tried installing both the zip and extracted folder.
The "Testing" tab on the addon page is active.
I have tried manually placing the folder into the addon folder.

When you attempt to install from a zip file, there should be messages either in the info window or on the system console that might give an indication.  Could you attempt such an install and go to the scripting tab to see if there are any info messages.  Also, could you use the Window menu to enable the System console and see if there are any messages on the console?  If so, please edit your question and cut'n'paste those message into it.  Finally, which version of Blender are you using?

"Modules Installed () from 'C:\Users\julia\Desktop\pymeshio-3.0.1.zip' into 'C:\Users\julia\AppData\Roaming\Blender Foundation\Blender\3.0\scripts\addons'"
I believe I am using Blender 3.0. I tried using the system console, but it didn't seem to do anything (I am not too familiar with using the system console).

You are using 3.0 (it shows up in the modules message) and since you're on Windows, the System console is just a window that display output.  You can open it by going to the Window menu in the topbar and clicking Toggle System Console.  It may have some text.  But the message you quoted says that pymeshio was installed.
There have been reports of behavior similar to what you are seeing and it may be that the authors of pymeshio will have to update it for 3.0 before it will work.

I will try older versions of Blender for these addons. Thank you.

2.93.6 should not have the problems and is the most recent older version.  Do let us know what you find out. pymeshio is definitely an old addon and unlikely to work with new versions of blender, but there should be error messages.

folders with dots inside tend to have issues being correctly recognized, you should remove them, it might help


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get position of object following a path via script
I have an object obj following a path, and when I run obj.location, it always returns the same value for every frame even though it's moving. How can I get the real position?

Use the matrix world.
An objects world matrix is calculated for every frame, to position all objects globally in the scene regardless of how it is done be it via constraints, parenting, drivers, yada yada.
To get the global location at frame f
context.scene.frame_set(f)
global_location = context.object.matrix_world.to_translation()


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how to speed up a video sequence in blender 2.8?
How to speed up a sequence using the video editor in blender 2.8? All tutorials I find online use older versions of blender.

Speeding up the video framerate (which is what I believe you mean by video speed) can be done the same way in 2.8 as it can be in 2.79 and before. In the render settings, switch the default 24 FPS to whatever is faster than that. It should speed up the video speed.

No, I meant selecting a sequence in the timeline and make it run 2x faster for example. Only a particular sequence, not the entire video.


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UV Unwrap a "fragmented" mesh
I have a mesh which is a collection of meshes with distinct geometry. It is the object on the left of the picture.

When I UV unwrap it, blender places the distinct meshes on a "grid" and "projects" those surfaces on the texture. The problem is that the meshe's parts are not in the correct position relative to eachother.

On the right object of the first picture, there is no partition on the mesh and the UV unwraps properly. How can I achieve the UV results of the object to the right for the object to the left?

In this particular case, a simple "Project from view" (with the view set like in your first picture) should do the job.

Thanks @thibsert, that did the trick!

Try project from view or place the uv islands manually to match the grid!
https://www.youtube.com/watch?v=Y7M-B6xnaEM
check this video for more info.

A screenshot(s)/video illustrating the other option would be nice.

https://www.youtube.com/watch?v=Y7M-B6xnaEM
Here :D

It is in the video at 4:06.


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My object isn't being render
I'm using Blender 2.81 and my object isn't being render.

All the aquarium renders fine but that "purple cube" on the right never appear on the render animation. I'm using eevee to render.
my object isn't being rendered - I don't know if this is the cause, in 2.81 the camera icon doesn't appear on that spot.

The camera icon exists in 2.8+, but you have to enable it, I don't really understand why though. Go to the little funnel icon in the top right corner of your outliner and enable the camera icon. Alternatively go to the object properties, then the visibility foldout and you can change it there

Thanks for the tip @Gorgious. I enable the camera icon and this object is "Enable in Renders" so i don't know why when i do the render animation it just disappear. See here a screenshot: https://i.gyazo.com/a9ecf89c4bdff8c3bad1071e3086c1f9.png

maybe give us your file so we can dig into it

OK, I think I know what's happening, it is actually something else. from the picture I think the cube is actually emitting particles ? If yes, you have to enable "render emitter" in the particle settings. Follow the second answer of this question : https://blender.stackexchange.com/questions/157179/object-missing-form-final-render

Thanks @Gorgious, it's working now. I just need to enable the checkbox "show emitter" on Render object. :)


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Camera view not working on BLENDER 2.8
I can't seem to position my camera properly so that my scene is in view all of a sudden. When I press Ctrl + Alt + Num0 a box with a blank screen is displayed and any attempt to position the camera moves it to a completely different position. My camera  is positioned as follows:

This is the view from the camera:

Any suggestions? This does not work in RENDERED/SOLID or Look Dev on BLENDER 2.8

Check the clipping range for the camera, it might be too small for your scene.

Is that under view when you press "n" or under camera itself?

https://docs.blender.org/manual/en/dev/render/cameras.html#properties


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How do I animate an object to follow two paths at the same time?
I have a sphere that has been set to follow a nurbs path.
At the same time, I'd like that sphere to follow another path that happens to be a circle, and that circle moves along the nurbs path too.
For some reason, when I add two contraints to the sphere, it follows the path but it won't follow the circle too, meaning it won't loop in a circle.
How can I possibly do that? Here's a picture:

It moves smoothly along the path, but the ball won't follow the circle.
How would you go about animating the same object twice?

You cannot follow two path. What you can do, is parent them…

Maybe you should let us know how the „resulting“ animation should look like…

Have the circle follow the nurbs path and the object follow the circle.

@Chris When I parent the sphere it pushes it away thousands of meters

@MartyFouts omg yes that worked, thanks a lot!

If you want an object to follow a path and that path to follow another path, the simplest approach is to do precisely that.  In your case, a sphere is to follow a Bezier Circle that is to follow a Nurbs curve.

Make sure that all three have scale applied.
Select the Bezier Circle and add a Follow Path constraint.
Set the target to the Nurbs curve and other settings as needed.
Select the Sphere and add a Follow Path constraint.
Set the target to the Bezier Circle and other settings as needed.
For each of the Bezier Circle and the Nurbs curve, set the Path Animation appropriately.

The Sphere:

The Bezier Curve

The Bezier Curve's path animation settings:

The Nurbs Curve's path animation settings:

Resulting 100 frame run:

Obviously You'll want to edit these things to suit your animation needs.

Thanks Marty, I just accepted your answer.

Appreciated.  It helps people know that your question has an answer when they're searching with similar problems.


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Smoke won't collide with my mesh
here's an image:

Smoke won't collide with my mesh, instead it goes through it. As you can see, my mesh has been given an Effector type: collision. What's the issue here?

please provide blend file if the answer doesn't help you

You can either try:

Increasing simulation resolution. (Will increase simulation time.)
Increase surface thickness on the collider object.


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Fit to curve array not working
I'm trying to make a fence and make it fit to a curve as an array but it won't work
Here's the image

For some reason unknown it multiplies it in a straight line

The Fit Curve option won't make your object follow the curve, it will just adjust the amount of iterations to the curve length. If you want your object to follow a curve, give it a Curve modifier after the Array. You can keep Fit Curve option in the Array, it will create the right amount of iterations.

Thanks a lot that did it for me!! You're a star <3 Ill accept the question in 5 min


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SVG file and Shrinkwrap modifier not working properly
I imported an SVG file into my project containing a bottle. The SVG file is supposed to be the label of the bottle and wrap around it however it seems to take on weird shapes when I apply the Shrinkwrap modifier or do it manually.
Previously I converted it to a mesh and combined all curves into one mesh.

I cannot tell from these images what is going wrong. You didn’t show more than one situation. What is the label supposed to look like? How does it start off (without the modifier)?

https://blender.stackexchange.com/questions/52904/wrap-curve-around-sphere https://blender.stackexchange.com/questions/23627/using-svg-to-put-label-on-bottle https://blender.stackexchange.com/questions/40901/setup-for-a-wine-bottle-with-multiple-labels https://blender.stackexchange.com/questions/8706/what-is-the-right-way-to-apply-an-image-texture-over-a-glass-or-plastic-material


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Rigging a loose character belt that's easy to move around/deform when character is posed/animated
I'm probably overthinking this, but...
What would be good way to rig this loose belt so that it's relatively easy to move around when the character is posed/animated without too much time spent tweaking controllers and avoiding distortion/clipping? Ideas about controllers/constraints/and other suggestions would be appreciated.

Maybe simply put a series of bones (like for example 6 bones) all around your belt, and parent them to the first spine bone?

Would pointing them up, down, sideways matter at all? Also, I figured similarly that I'd have the bones just be disconnected and parented to the spine, which I guess is what you're implying, but is there a way to keep them relatively connected, like some kind of bendy bone IK thing?

Edit: Nevermind, I'm an idiot. So orientating the bones that way would allow me to replace them with controller objects right on top of them. It's just that, I'd like to have some kind of smooth falloff when I move one bone, and it moves other ones a bit. I suppose location constraints would work here.

Bones pointing downards is probably the best solution. Sure you can parent a kind of belt root bone, the 6 bones will be parented to it and it will be parented to the bottom spine.

Okay. I'm going to test your series of bones with location constraints with an influence falloff and see how it goes. Thanks. You pointed me in the right direction. (I don't know why I didn't think about orientating the bones vertically...duh).


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Cycles doesnt render anything with gpu
When I switch to cycles, I chose my nvidia rtx 2060 (laptop) gpu.
But when I switch to the render viewpoint, the objects are "empty":

I use the newest Linux mint version
And my driver version is 470.86
Here my preferences:

Have you added a material to the cube?  If so, could you add a screenshot of your material shader (from the shader editor) to your question?  What happens if you render the image rather than view it in render preview mode?

Have you by any chance also installed the cuda toolkit?

Yes I have. Don't I need something with optiX?

@MartyFouts, when I render this with the CPU, I get lots of particles and shading effects like expected


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Deactivate collision between certain Rigidbody objects?
I have a model consisting of many seperate objects that are all overlapping with each other and I want to use Force Fields to "destroy" the model. How can I stop collisions between the objects while still letting them interact with the Force Field and a ground plane?

In the Rigid Body panel, under Collections, put the objects in different layers, put the ground on several layers at the same time (press Shift to enable several layers)

Two ways to do this:

Use collision collections to control collisions:

"Collections" here is kind of legacy; they're not like modern (2.8+) collections.  Instead, by assigning a rigid body to one of the 20 collision collection layers in the rigid body settings, you tell Blender that the object should only undergo collisions with objects that exist in at least one shared layer.  Here, the rigid body cube and floor are in layer 1; the monkey, as shown, is in layer 2.  So the cube lands on the floor while the monkey falls through.

Use constraints:

This is a little more complicated, but there are situations where 20 collision layers aren't enough.  In those cases, you can create rigid body constraints between objects to disable collision between the two, via the "disable collisions" setting on the constraint.  Here, I'm using a generic spring, but without any springs or limits, so it's essentially a "free" constraint that doesn't actually constrain anything.  So the monkey (now in collision layer 1) lands, but the cube doesn't collide with the floor, because of the constraint joining the two.


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I can't see faces on every model
Every time I enter edit mode, I don't see faces at all, just vertices. And that happens on every object/model. How can I fix that?
Btw I'm an absolute beginner.

Try ALT + H in edit mode ?

Doesn't make any difference :/

You've just gotta switch to face select by  clicking on it or pressing the number 3, but not numpad 3.

I've switched but still, there are no lines that make that "squared" shape.
Thank you anyways, appreciate it!
https://imgur.com/a/fyz5SFT


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How can I remove white from my backgorund layer?

How can I remove white from my background layer while keeping this blue color (because if I set the ground as shadow catcher I get only black shadow)?

There was an improvement on Shadow Catcher so check 3.+ ... Direct and Indirect light support
For compositing you can also enable Shadow Catcher pass ...

https://www.blender.org/download/releases/3-0/ https://wiki.blender.org/wiki/Reference/Release_Notes/3.0/Cycles#Shadow_Catcher


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Can't select or edit a curve in Edit mode
I now can't select or edit a curve in blender in Edit mode. I could before, but now I can't. I must have hit some key that changed a setting. In object mode I can select it, move, rotate and scale it, but can't do anything with it in Edit mode. I have even uninstalled the program and reinstalled it again but it did not fix the problem. This happens in a project I am working on now with curves that used to work but don't now. Even starting a blank new project gets the same result. Mouse is set for left-click select. I have searched the web for an answer and can't find one. I really hope that someone has an answer to my problem.  Thanks!!!

Hello :). Please add some images and perhaps share a .blend to illustrate the issue.

I figured it out. Too embarrassed to say what I was doing wrong :) Thanks anyways. I am sure I will have more questions in the future.

Glad you made it work :).


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Learning fluid simulation with blender 2.82, can't get the water mesh where i want?
I'm trying to learn the fluid simulations on Blender 2.82. I want to splash some water on the ground, but unfortunately, the mesh is always above the ground, it's like there is some offset between the data particles and the mesh.

I've been told to switch to 2.83 because they fixed the offset bug, but it's still the same, looks like it's not really a bug (or maybe it is) but maybe i'm just doing it wrong, any idea?

There is a setting that's called margin and it basicly is the offset to the object. You could try to reduce that

I only see the margin setting for the GAS, but i'm simulating LIQUID


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UV map slightly distorted for some reason
so I've been working on a mod for a videogame but I ran into a problem that I simply can't figure out on my own (I'm fairly new to blender but I honestly don't know what I've been doing wrong). So I modeled the object (an I-beam, pretty basic stuff -->started from a cube and added some edge-loops and did some extrusion and scaling) applied the scale and location and started to place the seams. Then I duplicated the object b/c I've been planning to bake a normal map later on. After that, I unwrapped the model but there always is this one part or rather loop of the unwrapped model which appears to be deformed for some odd reason. I don't know but I don't think it has anything to do with my placement of the seams but I might be mistaken. Anyway, I'd appreciate your help and please let me know if you need further information:)

could you share the object? https://blend-exchange.giantcowfilms.com/

wow didn't expect a reply so soon but yeah sure

I don't see the door, could you please just share the door?

there is no door just a vertical i-beam and a horizontal one but those are separate objects...the horizontal one is hidden and I haven't yet started to unwrap it so pay it no mind

oh my bad the object i was refering to in the post is the beam HV LP....i edited the file and hid it sorry

I guess it's because your beam is not square, it gets larger on its top, but anyway why does it bother you? is it just a theoretical question?

Well as I said earlier I tried to bake a normal on the low poly mesh of said mesh and I had some trouble with it (normal map looks kinda weird) and since I tried it before on a screw in the same blend file without having any problems I thought it might be because of the UV map distortion. Also, the beam gets larger by choice. anyway, thanks for the quick reply  :)

yes but the fact that the beam gets larger makes the distortion because the border of the horizontal face is not straight and the other one can't overlap this one, so it goes obliquely. Also, about the bake, maybe tell what's the problem. With angular object it won't be able to catch the faces that will be parallel to the normals, maybe that's the problem...

mhm yeah, that might be it...the normal map looks weird where the angled faces are...is there anything I can do about it except making the beam straight?

so there are 2 problems: your UV map and the bake. For the UV map, if you want it to be straight, I guess you need to put an edge loop somewhere so that the top part is square and won't tilt the face. For the bake, as I said a bake can't catch a surface that is completely parallel to the normal direction, so you need to slightly shrink some faces. If it's not clear I can try to illustrate both these 2 points (tomorrow though).

Oh an illustration would be nice if it won't cause you any inconvenience. Thanks again

About your distorted UV map:
it comes from the fact that your beam is actually enlarging on its top, so the faces are not perpendicular. The consequence is that it will stretch the UV map in the UV Editor: Blender just tries to find an average arrangement between faces, it doesn't know that it needs to give priority to perpendicular angles. I've made a second test with perpendicular faces and as you see it works fine.
What you could do though is making the UV map orthogonal with some addons, or: first unwrap the top part, then the bottom, then in the UV Editor, make the bottom faces stick to the top faces with the help of the snap.

About your Bake problem:
There might be several reasons, it really depends on your problem. I guess one of your problems is that your object is made of 90° perpendicular angles. In that case you need to know that, as the ray of the baking follows a direction that is perpendicular to the face normal, it won't be able to record any of the faces that are completely parallel or perpendicular... the baking will be completely "blank". Whereas if you slightly tilt those parallel faces the ray will hurt them and therefore they will be seen (the perpendicular face won't be seen but it doesn't matter, the parallel faces will give the illusion of deepness).

Wow thanks i think i got it now....about the normals man i'm such an idiot haha...i knew that and did the same thing you did when i modeled and baked the screw but for some reason forgot about it when i modeled the beam


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Selective alpha or removing alpha
This is my setup, I have a plane that I wanted to display 2 textures. The first texture I want to show only part of it. In this example, it is the circular ring. For the second texture, I also wanted to show only a portion of it, this is represented by the blue circle on my example.
What I wanted to do is to crop out the textures, i.e. the ring and the circle, but not actually make the object transparent. In my example, I should still see the rest of the object which is a plane. Anyone knows a better way to do this?

Here's the blend file I used as reference:

If you want to see something on your plane instead of transparency, plug the 2 nodes you use as alpha layers into a Converter > Math > Add, plug this Math into the factor of a Mix Shader, in this Mix Shader plug your current setup plus the background you want to see (here a yellow Diffuse):

thanks, kind sir, you are my saviour! that is exactly what I'm trying to achieve. sorry, I had to type this on the comment, but I felt it isn't enough to accept the answer, I had to express my gratitude. :)

thanks, there may be a simpler way but I didn't want to change your current setup

This is probably a side-note, it may not apply to your case. But in general, if you see shaders with identical settings but different colors being mixed, you should consider mixing the colors before they get to the shader, rather than mixing shaders; it's cheaper.
And, if you don't need Alpha further down your line, you can avoid that, too, by using the existing black-and-white masks as mix factors:

....

Thanks, Robin. I need every bit of information and help I could get. And your explanation is very nice and clear too. :) I will keep this on my notes.


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Extract or address each instance index
Let's say I have this simple setup of a Plane, instanced using a "Curve Line". I wanted to get the Index of each instance so I could use it down the line (i.e. pass it on later as the seed value) or pass it as an output of the geometry node. How do I do that or what node do I need to do that?

It is quite simple but not so obvious at first glance. You just use the Index node and plug it e.g. into a Translate Instances node. In my example I used it to move each instance a little further in X direction by plugging the index into a Multiply and Combine XYZ before the Translate Instances. Note that the index starts at 0.

If you want to use it outside of the Geometry Nodes nodetree for example in a material you can use the Index node as well, although it's not working instantaneously. To make sure you get the index of the instances and not the points of all the planes you have to take a Capture Attribute node which you have plug in after the Instance on Points node.
Then you set it to Integer and Instance and plug the Index node into the Value input. To make it work now you cannot directly connect it to the Group Output, you have to add a Realize Instances node beforehand. I'm not sure why this is necessary, since the instances should have their index before realizing them.
Then you connect the Attribute output to the empty socket on the Group Output node and give it a name in the modifier. I called it "col_index" and added it with an Attribute node in the Shader Editor. I used a Greater Than node to drive the Emission Strength on the material.

Of course you can combine both and create even more things with the index.

The Capture Attribute node is crucial to get the indices of the instances instead of those of the plane vertices. Since realizing instances seems to be necessary to transfer the attribute to the material, if you would capture the attribute after the Realize Instances node or plugging the Index node in the Group Output without capturing the attribute at all, this will result in the Output Attribute using the indices of the plane vertices.
For example, in the above image I used a 3x3 grid as plane, which makes 9 vertices per plane. In the Spreadsheet on the the left you can see, the value in the "col_index" column is 0 for vertices 0-8 (the first 9 of the first plane, instance 0), then the next values are 1 and so on. The Greater Than node has a threshold of 4.5, so the instances 0-4 are dark, the instances 5-8 have emission (the shine on instance 4 is a reflection).
The following image is to show the difference of not using a Capture Attribute node, I've set the grid to 9x9 vertices, resulting in 81 vertices per plane adding up to 810 vertices in total. As you can already see in the Spreadsheet, the "col_index" values are now 0, 1, 2, 3,... with each vertex having its individual index.
In the material this results in the emission no longer being turned on or off per plane, but per vertex. The Greater Than node has a Threshold of 343.5 which is far more than the number of planes, but not even half of the planes are glowing and the emission is only partial on the last of the glowing planes. The same would happen if you captured the attribute after realizing instances.

Wow! Very clear and you even went way beyond what I needed. Thanks so much! Not only did you answer my question, but you also provided a very clear explanation and other use cases. :D Thanks so much!

That capture attribute node always skips my mind. I've seen that before, but I forgot that it existed

@Sophia At first I didn't use it either but it didn't work ;) And as I said, I have no idea why I have to realize instances, since the instances should have their indices without realizing them. I only know if you used the index on the realized instances without the capture attribute beforehand, the index of all the vertices will now be taken into account. Maybe I'll add this information to the answer.

in my version 3.3 alpha  it's even weirder. it works only if i set capture and output attribute to float....♂

@Chris In my 3.3.0 Alpha it works with Integer...

maybe mac version problem....i have no idea

@Chris maybe because it's alpha ;) That's why I usually give answers with official releases. Some things might even change from alpha to final release.

of course they will change ;) that's what i expect. but i like to play and test the newest features ;) maybe i love the risk :D

@Chris Oh, I'm testing new things as well, but I won't base answers on them - only in the form of "not possible yet, but maybe in the future because this feature is already in alpha". For the same reason questions are usually closed if they are asking for something not working or missing etc. when it's regarding alpha or beta versions.

yeah, but this is one of the rules here...which i think - is ridiculous. Maybe make a flag to the question "it's an alpha version question" but to exclude those...that's one of the things i don't like about this site. So you can't ask question about new features as GN is....ok, now it's released but...yeah...but makes no sense to discuss it...that are the rules...i cannot change them...i just can use my time for other sites...which are much more free and open ;)

@Chris The problem with new features is, as long as it's no official release, whatever you are doing there and whatever solution you find might work in exactly that build, but can be different in any build before or after... even names or labels might be different. And I'm not talking about fully working features that are just waiting to be released, that's one thing. But everything that doesn't seem to work or exist might be there in the final build, so a question arousing on this might be just a temporary problem due to impatience and not waiting for it to be completed.

The same is true for different Blender versions…♂

@Chris I guess, as a programmer I look differently at things like alpha, beta and final versions since it is a difference if you release something that's supposed to be a final working version and a work in progress. If someone tells me on a work in progress something's wrong I have that kind of disclaimer saying "yeah I know, never claimed it would all be working". In a final version things may be different than in previous versions, but supposed to be finished and working until they get an upgrade.


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Geometry Nodes Merge Proximity
I'm trying to create two 3D objects like this:

but with their edges merged like this:

using geometry nodes.
Can someone point me to some resources that will let me do this? I tried convex hull, it isn't what I wanted. I tried to fake it, but it doesn't look right.
I wanted it to be a bit tighter between the two objects like this:

I tried this tutorial:
https://www.youtube.com/watch?v=mA3YnlwbI10
but the result doesn't look good. I will try to play around with the parameters to see if I can get it to look like what I wanted.

You could do a GN tree like this. Put all the objects into a collection, then convert join that with the current object, remesh it and then add a smooth modifier after that.

Result:

You could also try using the metaball object type. Not exactly GN but it's also specifically designed for exactly the purpose you're talking about.

thank you so much, jakemoyo. it is exactly what I was attempting :)


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my mesh got spikes and idk how to fix it

soo.. im working with blender for the first time with a tutorial, and after i did some sculpturing, my whole mesh started to do this.. i thought it was a visual error from reloading the view or so but after reopening the software i had the same problem.. does someone know a fix to this?

so how does it look like in Edit mode?

I'm quite new to Blender as well, but my first thought is that you need to recalculate your faces. Have you tried that?


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Why is the inverse kinematics not bending straight, but rather slightly off to the side?
No matter what I do, it doesn't seem to bend straight. I added a proper 3 chain lengths as well. Here's an image as to how it bends:

I figured it out. You would need to prevent the IK controller from moving your foot at the same time as the rest of the leg.
First, select both the foot and the foot's IK controller in edit mode, and press "CTRL + P" then "Keep Offset" which prevents it from moving.
Then, to prevent the foot from detaching from the leg, go into pose mode, add a copy transform bone constraint, select your armature as the target, and for the bone select the shin/knee bone. Set the Head/Tail option to 1.
Finally, reorientate your pole angle in the shin/knee IK constraint and you're done.


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Why does my shrinkwrap modifier restrict vertice movement over a sculpt that I am trying to retopologize?
For whatever reason, my shrinkwrap modifier is restricting me from moving the vertices where I need them to go for topology. I am trying to retopologize a sculpt, and it's impossible to do with this issue. Maybe I'm missing a step or I screwed something up, but, help would be appreciated.
Here's a gif of the problem (sorry for the terrible quality):
https://i.imgur.com/CFym59J.mp4

Hmm, looks a bit like snapping is active (but the icon indicates that it is inactive). What happens if you press the Ctrl key while moving around? What happens if you disable the Shrinkwrap modifier?

When I press the ctrl key it makes the snapping far worse, and when I disable the shrinkwrap modifier it moves normally as it should


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Multiple-boned meshes breaking when I move armature
I'm trying to figure out why the area where two bones connect on a mesh will mess up when I pose the model around.
(normal) https://i.sstatic.net/FxLba.png - (posed)
https://i.sstatic.net/PXR3N.png
armature modifiers https://i.sstatic.net/bQ3Fy.png

Please clarify your specific problem or provide additional details to highlight exactly what you need. As it's currently written, it's hard to tell exactly what you're asking.

Create a single armature with the head and jaw bones in it. You shouldn't be making a new armature for each bone. The hierarchy in the armature should have the head bone as the parent of the jaw bone, so that when the head moves the jaw does too, but not vice-versa.
With the head bone armature selected, go to edit mode. Select the head bone, hit shiftd to duplicate it. Select the new bone that was created, rename it to jaw and move it to the jaw position. With the jaw selected, hold shift and add the head bone to the selection, and hit ctrlp to make the head the parent of the jaw. Choose Keep Offset otherwise the jaw will snap back to where the head bone is. Pay attention to the order things are selected when parenting. The first selected item(s) are the children, the last selected thing is the parent.


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Which denoiser is better?
In blender 2.81a, there are two denoising tools:

Under layer properties, you can scroll down and enable denoising
Also in layer properties, you can check "denoising data" under passes > data and in the compositing workspace, you can add a denoising filter

Is there a difference between these two? If so, what is different and is one of them "better" (faster, more efficient etc) than the other?
Any help would be appreciated. Thanks

For now Intel's OpenImageDenoise is superior to all the other ones. From the release notes:

Compared to the existing denoiser, it works better with more complex materials like glass, and suffers less from splotchy artifacts. It also gives better results with very low numbers of samples, which can be used for quick previews.

It is implemented as a post processing step, so it's easy to set up and thus not exclusive to Cycles, means that the node also allows to denoise EEVEE renders as well as images synthesized by other render engines.

Also see: What are the differences between different Denoiser options built into Blender?

Just to add: the Denoise node targets ray-traced noise. So it doesn't work on external images. And denoising Eevee renders has some limits - hashed shadows and reflections are not denoised.

I think that's covered by "synthesized images" @ᴊᴀᴄʜʏᴍᴍɪᴄʜᴀʟ Anyway feel free to edit my post.


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Disable deforming with armature
I want to create an animation of a stormtrooper. For test purposes, I've set up a simple armature with some cubes as armor. When I parent them to the armature and move/rotate bones, the cubes get deformed. However, I only want them to follow the movement of the armature but not deform since the parts of the armor should be rigid.
If I turn off "deform" in the bone properties, the cubes just stop to follow the movement of the bones.
The .blend file is available here:
It is just some cubes parented with automatic weight. I've made an colloection "old" with the same cubes but not parented.

I've found the solution! If you go into Weight paint for the disformed object, you can select individual bones. In my case, I selected the left upper arm bone and then painted the cube blue, so that a rotation of the arm bone doesn't affect the other cube


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Subdivision Surface messing up image texture?
I am currently modelling in blender and have created my own image texture in photoshop. Here is the version withouth subdivision surface:

Here with SS turned on:

As you can see, it looks very weird in regions where multiple vertices are in the same spot (I used that to create the triangular shape of the wings). I've gone through all settings in the SS menu, but none could help.
I've also made sure that the image texture covers all faces that it should completely, so this cannot be the issue.
Any help would be appreciated!

I am not sure, but having multiple verticies may be the problem. Merge them Alt + M and then see what the results are.
Some other things to consider are what your edge flow is like at those positions. If there are no edge creases or loop cuts, then the subdivision modifier may round your objects at those locations. With lighting, normals etc, this may be giving you that appearance?

thanks, this solved the issue! I always thought that you shouldn't have triangular faces, this is why I did it like that


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How to add many small windows/lights to object?
I'm currently trying to do a Star Wars scene in blender and realized that all large spaceships/space stations have lots of tiny windows on them (which appear as lights):
  (image from Rogue One - A Star Wars Story)
How can I replicate this effect in blender? The model I use didn't come with any texture for the lights. I've been trying to do a mix material based on a noise texture, but the result doesn't look very good:

I think the reason for the not looking good is that the lights are too dense and not rectangular. Another reason might be that some of the lights are placed too close to edges where it wouldn't be plausible for a window to be in real life.
How can I replicate this effect in blender?

I think Voronoi with 0% randomness sells the effect:

You can also add some noise and texture to detect areas where you want to have lights:


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How does the mirror modifier work?
I'm using Blender 2.93, and I've seen so many YouTubers just apply a mirror modifier and they're able to create two objects. The only way I know how to use it in this version is to add an empty object like a hook and use it as the mirror object. But I've started sculpting recently and I'd like to do it the way it's done in this video: https://youtu.be/Lso8KitmchY. I've heard that you can mirror two objects using the world origin but I tried that and it didn't work. Either I did it wrong or I still don't fully understand how to do it. Any ideas, descriptions, or alternative options would be appreciated.

Does this answer your question? Symmetrize option doesn't mirror bones on the axis

The Mirror modifier in Blender works based off the objects origin. If you want to mirror the object as a whole you will need to go into Edit Mode and move the object off of it's origin point. Then when you use the Mirror modifier it will mirror the object on the chosen axis based on how far from the origin it is.

Right, I think I got it now. I was doing everything in Object Mode. Thanks!

Happy to help! If this answer worked for you would you mind marking it as solved?

There's no such thing as using the world origin in a modifier. Modifiers either use the current object's origin (which you can set to anywhere you want) or another object's origin (which you can also move anywhere you want.
In either case you can do it so you effectively have your modifier acting from the world origin.


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How come my hair particles won't stick to the mesh?
So I made this character and I used hair particles and weight painting to create the eyebrows. Then I created the armature and used automatic weights after parenting the mesh to the armature. When I went to move head around I noticed the eyebrows didn't move along with it, which is confusing because I thought they were supposed to stick to the head. I'm not worried about the eyes and the teeth but the eyebrows confuse me. Does anyone have any idea why this is happening?

Particle Systems and Armatures are applied as modifiers, so modifier stack order counts. Make sure the Particle System is after the Armature.

Aaahh very good! That must be it. Thank you


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Is there a way to take an object with a mirror side and make it one whole object?
So I have this model that I retopologized, and it has the mirror modifier applied to it. The entire left side is mirrored. I want to rig this model for animation, and I just wanted to know if this mirror modifier is going to interfere with the posing this figure. If it is, then how do I solve this problem? I would imagine there's a tool that makes it a whole mesh, but I just need some clarification. If no such tool exists, and the mirror modifier is going to be a problem, then what should I do? I'm using 2.93, by the way. I only say that because the mirror modifier seems to work differently with each version.

On default settings, a mirror modifier does make a whole mesh (via "merge" option.)  Applying a modifier has a special meaning in Blender and I think you're probably not using that meaning (see the modifier dropdown, see what happens when you "apply" the mirror modifier.)  It is possible to use an armature modifier with a live mirror modifier; the mirror mod needs to have vertex groups enabled, bones need to be named appropriately (.L, .R), and the mirror needs to be before the armature.  Answering as a comment because this is probably a duplicate.

Once you're done mirroring you can apply the mirror modifier and the mirrored side will become "real"

That took care of it. Thanks!


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How to save and load a .blend file from a alpha version?
I was working with blender version 3.0 and was using geometry nodes that aren't available in previous version. I can save it, but when I load it again it opens in blender 2.93, and the nodes that aren't in this version turn red and change their names to "undefined". I was trying to right click on the file, choose "open with" (or whatever it's called in English) and select blender 3.0, but it still opened in 2.93

Your OS has associated the ".blend" file type with version 2.93.  If you want to open a file with 3.0 alpha you need to find the 3.0 alpha binary on your disk, run it, and then use the open menu entry.

Use drag & drop to open the file with a specific Blender version if you have mupltiple versions on your PC:

start the Blender version that you want to use.

open the file manager/explorer and drag & drop the blend file that you want to open into the started Blender

confirm the little dialog that appears in Blender with "Open".


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Does anyone know how I can model hair like this?

I like the stylization in the hair of this character but I do y know the process to follow to get the style. If you have any ideas feel free to say. Thanks

You can duplicate the faces of its head, then separate as a new object:

Extrude the edges to create the strands:

Give it a Solidify modifier and apply it:

Make the extremities thinner, etc:

nice!!! The master works on weekends as well....+1

Hello Chris, thanks but as I told you I've got a whole team 100% dedicated to BSE's answers, and now we are growing worldwide, this is crazy

By the way you should better buy some Moonboots International stock options RIGHT NOW

Ok, what’s your stock‘s symbol? I don’t know what to do with the billions on my bank account and now the inflation shrinks it like hell…


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Blender only render one frame of animation
I have a 300 frame Eevee animation, but when rendering I only get multiples of the same frame. I have looked at similar posts on Stack Exchange, but they don't solve my problem.
Animation works perfectly in viewport. I render using Ctrl + F12. Cloth physics is baked for the animated object.
Blend file: https://we.tl/t-yFyttsa6aH
Render settings:

Frame that get rendered:

I opened your file and I get empty render also for a static render.

Does this help? https://blender.stackexchange.com/questions/5285/blender-is-rendering-an-older-version-my-project

I deselected these two options and I can render the correct animation:


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Why do I only get one bezier handle on a point in graph editor?
I am animating the Factor of a Cast modifier and and would like to smooth out the animation by using bezier handles. But I only get one handle on the right side of the point. Where is the left one? I've marked the point in the screenshot below.

The left handle is probably very close to the curve point or too small on the current graph. Select the point you want to modify and press numpad period (.) to zoom in. Or press V to change the frame handle

Thank you. I've tried that to no avail, but I figured out that if I change the point to the left (frame 1 in screenshot) to a bezier, the left handle appears. So I guess the previous point have to be a bezier for the left handle to work. Don't understand why though.


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my reference photo has a weird rotation

I am completely new to blender. I am following Blender Guru's instruction too create a 3d coffee mag. However, when I add a reference photo, it has been rotated automatically. I am pretty sure that I have never changed the coordinate. Why would this happen? What can I do to fix the problem?

Hi, welcome! You didn't add many details about how you added that image (did you use the addon "images as planes"?), or about your current "image object" like the current rotation, that you can view in the interface... if you mistakenly rotated it by accident, ALT-R performs a "clear rotation" command... try that first.

You probably weren't in a front view when you imported your image, so select it and press AltR to reset its rotation. S to scale it, G to move it.

Thank you very much. That's exactly my mistake.


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Problem related to temperary border in Blender 2D
I know that we can create a temporary border by alt + LMB. However it doesn't work on my computer. It switchs to other dimensions instead. How can I solve the problem?

IDK what a temporary border is, ALT LMB does nothing with my setup. Do you want to restrict render, view, 3D view?

@Frederik Steinmetz
Sorry for unclear, I mean the temporary boundary stroke for filling color in an open area.


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Number of users of Node Group is wrong
Maybe this is a silly question but I have a Node Group in a Material, and the node displays "2" as the number of users, but I only have 1 sphere in the scene, that's all, which is used to test the material. There are no other objects. So I wonder why the 2 users instead of 1.
I searched before asking the question and all I found is this, but since I'm a newbie I don't really know if it's about the same thing or not:
https://developer.blender.org/T39552
Thanks a lot

Hello :). The users number is about materials. Perhaps there's another material with the same nodegroup?

Select the material, press Shift+L and choose material.
This will select all the objects sharing that material.
If there are no selections either you have 2 material slots with the same material on your object or the object in question is in another scene.


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What are the units for camera shift?
I'm having trouble making sense of the units of a camera lens shift.  It ranges from -2,2, defaulting to 0, but it doesn't seem to be in scene units, nor does it seem to be in radians.
Anyone have an idea what the values represent?

It seems to be in percentage or fraction of the render size (in pixels).
That means that a lens shift of 1 shifts the camera exactly one frame unit in a certain direction, making it frame exactly outside the previous default framed area.
This is measured however in relation to the largest dimension of the rendered frame size. So lets say you are rendering in Full HD, that is 1920 x 1080 pixel image; a frame shift if 1 unit will shift exactly 1920 pixels in any direction, that is up/down/left/right.
This may seem obvious while shifting sideways towards the X axis, but might seem random while shifting in the Y axis.

Very insightful!  Accepted.  I was only tweaking the y-shift, so it did indeed seem random.  Thank you.

@user48206, Duarte, this is not random : have a look at the camera shape from outside in ortho view (the 3D View ortho, not the camera ortho)

Yes, I know it's not random as stated in my answer, I meant it might seem random while controlled from the smallest render dimension, since 1 unit will not correspond to exactly one frame size shift.

For the Calculation of the smaller dimension* with the Resolution of $1920$x$1080$. If the larger dimension $1920$ has a Value of $1.0$, than the value to shift the camera along the full smaller dimension of $1080$ is:
$1080$px$/1920$px$= 0.5625$

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


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Get location of keyed particles
I would like to know if its possible to get particle location, scale, rotation of particles used in keyed physics settings.
I've tried using location, but I believe this is only the location of the keys used.
name = psys.settings.dupli_object.name
package = Package()
package.name = name
package.alias = name
i = 0
for p in psys.particles:
    if (psys.settings.type == 'EMITTER' and p.alive_state == "ALIVE"):
        pm = p.rotation.to_matrix() * p.size
        frame = [pm[0][0], pm[0][1], pm[0][2], p.location[0],
                 pm[1][0], pm[1][1], pm[1][2], p.location[1],
                 pm[2][0], pm[2][1], pm[2][2], p.location[2]
                 ]
        package.addFrame(frame)
exporter.addPackage(package)

Do I need to make a calculation according to the key location? I'm not sure how I can reach the data of the particles in the keys

Related


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BlenRig Mouth Control Issue
Not sure if anyone around he re knows but I have tried to use BlenRig to rig a character I made. Everything works except certain controls from the mouth_ctrl control bone.
I can move it side to side and the mouth moves correctly but when I move it up and down the mouth does not open like it is supposed to. The Vincent Character that is rigged using BlenRig works fine. Is there a control or setting I am missing?

This behavior might be caused by having the property JAW_ROTATION of the mouth_ctrl bone set to zero. Setting it to it to 60 should solve your problem.

You can find it in the CUSTOM PROPERTIES panel at the Blenrig 5 tab (like in the image above), the Properties panel at the Properties shelf or the Custom Properties panel at the Bone tab in the Properties window.

authors: Сергей Сергеев

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


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How to set up keyboard shortcut for bounding box viewport shading?
I want to set up key shortcuts for viewport shading modes. Problem is, I can’t figure out which keyword is the mode for Bounding Box.
I’ve got the other ones working, Rendered, Material, Textured, Solid, Wireframe all work.
I’ve tried the following: BOUNDINGBOX, BOUNDING_BOX, BOUNDING, BOX, BOUNDS, and several variations, none work.
Here are the user input values:

Might you know which keyword works for “Bounding Box”?
Thanks.
Edit: In case it helps, the Context value is: space_data.viewport_shade

Go over to the 3D View Header, right click over the Viewport Shading Mode menu and choose the option Online Python reference.
That should take you to the Blender's Official Python API Documentation where you can learn all about it.
There you will learn that the the viewport_shadeproperty is an enum that accepts [‘BOUNDBOX’, ‘WIREFRAME’, ‘SOLID’, ‘TEXTURED’, ‘MATERIAL’, ‘RENDERED’]string values.
The one you are looking for would hence be BOUNDBOX.


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Bezier curve normal size length
Is there a way to change the length of the displayed cyrve normal arrows when working with the Bezier curve? I'm using metric for my scene and I'm doing a small cable and this "centipede legs" are just disturbing. Is there a way to change the length?

I found a solution myself in menu N and the options in Curve Display.


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wrong/none texture UV mapping

I am trying to map mamooth fur texture to my model using 'Project from View' function.
Wherever I move selected faces in left window, the result in right window stays unchanged.
Can anybody explain me, what mistake am I doing? Thanx

It looks like it is the same image, so I suspect that the same UV map is not being edited and used. Check the mesh data and see if there is more than one UV map.

Thank you! I do not know what I actually made but according to your advice I found and deleted some UV-maps in ObjectDataProperties and it worked!!!

your welcome. You can add the solution as an answer to your own question to help future stackexchange users.

Probably not the same UV map was being edited and used.
I found two different UV maps in MeshData-ObjectDataProperties.
Removing of the second UV-map solved my problem!


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How to rename geometry main group inputs so they reflect in the dopesheet as well?
I am trying to figure out how to rename the properties in the dopesheet to match that of the main inputs of the main geometry group but there seems to be no user-friendly way to do this? Am i missing something? It can get confusing with so many inputs to animate. In this example input_12 is the _asdf named input but in the dopesheet it only shows input_12 instead of _asdf

The dopesheet show the data path, not the name.

@XY yes. so how do i change the name in the dopesheet?

It's currently not possible (AFAIK) but I hope it will change at some point.

@Gorgious oh ok. thank you, at least now i know why i couldn't find anything XD

As Gorgious has mentioned this is currently not possible. you can use group channels though to help organize the dopesheet


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Why does Cycles render Weird even w very low subsurface scattering?
The cycles renders completely different from Eevee even with a very low subsurface scattering of 0.06. Or is 0.06 too high for plants? If i set it to zero it's fine but should it not have some value?

Cycles and Eevee us very different approaches. Cycles simulates light while Eevee is more of an approximation.
This looks like render noise to me, so I'd say it probably is too much SS. Also I don't think the stem of the plant would have much SS to begin with.

The value is in units, and can be translated to meters, so 0.06 is 6 cm. If your subsurface radius is around 1 m, it means the light will scatter under the skin of your objects for roughly 6 cm (This isn't how it works under the hood but I think it's close to what actually happens). So if your stem is less than 6 cm wide, light has a chance of completely traversing it without being reflected back. Hence the fruit jelly look. So either you lower the subsurface radius vector or you have to use a very low subsurface value

You have a procedural texture directly connected to a normal socket. You can't expect any type of coherent results with a setup like that

I second @DuarteFarrajotaRamos opinion, try removing the Normal input on your Principled shader, bet money that will fix it.

@Gorgious hey you are right! my plant does start growing from 6cm until it's huge 12m tall full fledged tree. so i probably need to animate the subsurface scattering value from 0 to a certain bigger value.

That is because subsurface scattering is greatly dependent on the actual scale of the object, bigger objects will require higher values to have the same amount of SSS while small objects need smaller values. You also need to have a bump node between the procedural texture and the normal channel.


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Why does a random number geometric node sometimes need an ID?
Why does a randomly generated number sometimes need a mandatory ID? I'm currently reluctantly putting a random value just so it works. It works on the right screenshot without an ID. I can see though there is a broken line for the case where it treats the ID optionally.

If you tried to connect Random Angle to your "Plant.." node, or Random Value to your Angle to Radians node, you would see your problem is not about the random nodes at all :)

sorry i was supposed to ask for the purpose XD but nevermind it's fine thank you for the quick response!

well it's fine i think i found it https://github.com/blender/blender/blob/master/source/blender/nodes/function/nodes/node_fn_random_value.cc

it doesn't "need" it. you have to differentiate between different type of input/outputs. The round sockets are single values/vectors, the diamond shaped are functions/multiple/calculated values.
The random value node "normally" is a function which gives multiple different random values. But if you want to plug that into a round socket of another node it won't work because you have to plug in round in round and diamond in diamond. So you can change the random value from multiple values to only one value by plugging in a ID and you will see that the diamond output changes to a round output.

hey thank you for the quick response! hmmm maybe i should have rephrased the question. I was wondering what the purpose of the ID is for single values. Why would a function of values not require an ID and a single require an ID.. i'll probably have to check it's usage in the open source code on git hub XD

ah i think i found it. https://github.com/blender/blender/blob/master/source/blender/nodes/function/nodes/node_fn_random_value.cc


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How to convert or merge a tube into a single line curve?
i was only able to find posts about creating tubes from curves but found nothing about the reverse. converting mesh to curve will not work, it will give me a single circle of the cross section. Is it possible to automatically convert this into a single line curve? or even just a mesh with with single points merged at the center from each cross section edge.

if your curve has not to sharp curves, you can do this:
go to edit mode, ALT+S , scale down to "line", M  -> merge by distance to get single vertices -> convert to curve

to change the spline type, just go to edit mode -> curve -> set spline type

I usually do this:

In Edit mode switch to Edge select mode and manually select a single ring loop
Go to menu Select > Select Loops > Edge Rings (now you should have all ring loops selected)
Press M (or menu Mesh > Merge) > Collapse
Convert back to curve with Alt + C

I had to do this the other day, if your curve is more complicated than the great example given, this slightly different method works well.
In edge mode select all then alt deselect all the long edges so you just have the loops selected (or select edge rings if that works for you, depends on the mesh)

make sure you have individual origins selected

then just use standard S to scale down each ring

Once the ring size is less than the distance between each ring to merge by distance to make it single vertex

then you can do limited dissolve if you need to simplify it more and once happy do convert to curve
works great.

one other trick, if you enable the simplify curves addon that's included instead of decimating first you can use that to make a copy and force it to output bezier curves then you get a nice, optimised curve that easy to manage.


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Item in Outliner is Incorrectly Organized And Can't Be Removed
There is an item in the outliner ( 3rd red box) that I have already organized into a folder (2nd red box). And I understand that it is under one parent object so it appears a second time (1st red box) and that's fine but the 3rd appearance of the item should not be there and can't be moved or removed. I mean i can disorganize and move it into another folder but i want it removed because it causes confusion. Why is it there and how do i remove the 3rd appearance (3rd red box). I've noticed it happens alot with other items as well.

I'm a bit lost with your organisation but when you move a parent into a collection, its children stay in their current collection, it may be the problem here, so just move the child object in the same collection as its parent? Also an object can be part of several collections, if you right click and Unlink it will be removed from the collection but will stay in the other ones it is part of

ah cool, i tried this unlink before and it deleted what was in the 3D scene. but this time around it worked thank you!

If you move a parent into a collection, but don't move its child, the child will stay in its current collection. Now if you want you can move the child in the same collection. Another thing is that an object can be part of several collections, if you right click and Unlink it will be removed from the collection but will stay in the other ones it is part of.


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Blender freezes when rendering
My specs are:
CPU. Intel Core i5-8300H
GPU. NVIDIA GeForce GTX 1050 (4GB GDDR5)
RAM. 8GB DDR4, 2400 MHz.
Blender instantly freezes up the screen when the rendering button is issued and the only way to go around this is to do a restart. How can this problem be solved?

HI, welcome! Difficult to say exactly, but that suggest some sort of hardware issue. Maybe driver (check version/update), maybe memory (perform some test), maybe excessive heating (check temperature)... I've the same card on my laptop and that never happened to me.

are you using eevee or cycle? are you using CPU, GPU or both?

I've used the CPU, it freezes. The same thing happens when running Blender on the GPU. Cycle.
The drivers are all up to date. RAM is enough. Temperature stays at 50 85 degrees which is normal I guess.
Hmm, I still don't know what causes this.
I tried rendering the output as a jpeg file and it still freezes..


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How to export water simulation/animation from Blender into Unity?
I've created a mantaflow water scene and want to export this 3D simulation/animation as fbx  into my Unity project. Is there an easy way to do this? Beginner level.

No way. Fbx doesn't support this. You can export each frame as a different obj file and change them at every frame or you can use alembic (abc).

Thank you so much @FFeller!

Mesh simulations can be exporter to Unity via Alembic, with some limitations:

NOTE: Supported build platforms: only Windows 64, MacOS X, Linux 64,
and Stadia.
The Alembic format is commonly used in animation to transfer facial,
cloth, and other simulation between applications in the form of baked
data.

Alembic was already advised in the comments. But... What do you mean by building for windows/mac?

I mean if you work on an Android project it will never play on the build. Alembic for Unity only supports the following build targets: Windows 64-bit, MacOS X, Linux 64-bit, and Stadia.


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How to Export this final product with Sound Animation to Unity?
Is there a way to export this animation into Unity, with all the material settings (especially the water droplets on the apple) AND movement intact from the "bake sound to f-curve" feature?
Here was the tutorial I basically followed to build this product: https://www.youtube.com/watch?v=l8RHRNZQEuE

I'm confused, where is the apple? You can't export modifiers other than armature, They will be applied before export. Bake to f-curve works, but you'd have to do that to a channel Unity  understand, either loc, rot or scale. To give you more information, I need to know where the apple and the droplets are.

Thank you @FrederikSteinmetz , sorry for the confusion, I was also working off of this beginners tutorial with the apples: https://www.youtube.com/watch?v=DOm2K9jOZLI  I was able to export the droplets over to Unity, although I was hoping to retain the same appearance after the export, but looks like that's not possible.


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Terrain Modelling
all. I am new to Blender. I have modeled a terrain by joining the edges of different contour lines which I imported from a DXF file. However, I have no idea how to continue creating a small hill on top of a closed polygon or surface. Next, I would like also to know whether there is any tutorial that I could refer to in order to know how to place a road nicely on the terrain surface. Please find the Blender file if needed. Thank you.

enter link description here

Hi. Please make the title of the question specific to what you are asking and not just the general topic. Thanks.

The hill
For your small hill, I'd use Loop tools. It's an add-on that comes with your standard Blender.

Select two layers of vertices and Bridge them.

It's wise to subdivide longer edges since Looptools Bridge will not handle them great in this situation.

The road
As for your road, you could use a bunch of modifiers for that. Mainly Shrinkwrap, and a few others that increase the detail of the mesh geometry (more vertices) to help Shrinkwrap work better (give it more vertices to work with).
First something like this:

And then move the road above the hill (z-axis only) and press ALT+C and convert it to a mesh. (You could apply a Subdivision modifier first for more mesh geometry)

And finally apply Shrinkwrap (and some other modifiers to make it look a little bit nicer) The road is now projected on to the mountain surface from a top down perspective. (Note how the "Mode:" is set to Project.)

The road is shaped a bit funny where there is no mountain underneath it; that might need some manual editing/tweaking I'm afraid.

Go to EDIT MODE, select two vertices and press F (to create an edge or face).
Continue pressing F to generate all the faces (vertices have to be aligned).
STEP 1:

STEP 2:

probably there is also a better and automated way with extensions. did you look for them?


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Simple script for pasting node to every material. Can't figure out
I have model from Sketchup which have like 700 materials and I need to create/paste specific image texture node in every material for baking one diffuse texture to later create one material.
My script is not working like I think it should. Can You help?
import bpy
object = bpy.context.object
for num in range(1, 700):
object.active_material_index = num
bpy.context.area.type = 'NODE_EDITOR'
bpy.ops.node.clipboard_paste()

I don't know exactly how to copy/paste nodes between materials, but this solution works anyway.
I suggest to have a reference to the image texture node you want to duplicate inside your blend file data. To do this, choose any material that will be used as source (srcmat in my example), and add the image texture node you want to duplicate in its node tree (set the image too). Assign a name to this node (mynode in my example) from the N sidebar.

This lines of codes will create a new texture image node for all the other materials assigned to the object, then assign the texture you set in mynode node and finally link the texture to the color input of the Principled shader node:
import bpy
from mathutils import *

# replace 'srcmat' with the name of your source material
# replace 'mynode' with the name of your image texture node
srcmat = bpy.data.materials['srcmat']
srctxtnodeimg = bpy.data.images[srcmat.node_tree.nodes['mynode'].image.name]

# select your object first
o = bpy.context.active_object

# create the same node on all the other materials
for i in range(len(o.material_slots)):
    o.active_material_index = i
    m = bpy.data.materials[o.active_material_index]

    if m.name != srcmat.name:

      mnodes = m.node_tree.nodes

      newnode = mnodes.new("ShaderNodeTexImage")
      newnode.image = srctxtnodeimg
      newnode.location = Vector((-100, 500))

      princshader = mnodes.get("Principled BSDF")
      m.node_tree.links.new(princshader.inputs[0], newnode.outputs[0])

P.s.: you can add other properties of the source node such as color space, interpolation or projection if you need. Moreover I assume that all your materials (created after import from Sketchup) use the Principled BSDF shader, which is (based on my experience) the default shader used by Blender in any situation (eg if you import a model).

(Not enough reputation to add a comment yet) Giuseppe G.'s solution works when using the loop index as an index into the object's material_slots (as opposed to into all of the scene's materials)
so
m = bpy.context.object.material_slots[i].material

instead of
m = bpy.data.materials[o.active_material_index]


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Duplicate and scale edges but keep in the same mesh
So I am working on a low poly car, I forgot to add more detail around the wheels, so I want to add new edges at the exact position as the current but scaled up. I am not the most advanced blender user and can't seem to find a way to basically extend these edges but keep one connected to the outer face and the other connected to the inner face of the wheel.
See:

How would I achieve this? Thanks!

There may be a snappier way, but I would:

CtrlB bevel the outer curve of the wheel-arch, Segments 2, Profile 1
CtrlX dissolve the surplus loop on the inside of the arch
Select the new edges, and GG with C Loop Slide to adjust the depth of the new loop's offset..

..depending on your previous use of the Loop Slide, you may have to hit E to get the sliding loop to be parallel to one side or the other, and maybe F to flip which side.

Thanks! I didn't even get the extra bevel so it was very easy. I will keep this in mind for the future. The whole side of the car is one face now so I will get that triangulated later, that is why i had problems with this.

Great! I think maybe you should have got the extra bevel.. maybe that's a sign you have some double-verts in there or something, perhaps  check your topology  to make sure you'e not going to have problems with shading, etc.

One option is to select the huge polygon that makes up the entire fender section, and press i to inset, then move the mouse until you get the thickness you want. Granted, this will create new edges outside the entire perimeter of the selection, instead of only at the wheel hub. But in your particular case, given that you're at such a low poly stage, the extra geometry this would bring might actually be welcome.


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Boolean Difference Modifier not applying consistently (see pic)
Thought it would be fun to create some 3D printed keyrings for my business and seem to have got stuck at the first or second hurdle.
I'm trying to use the boolean difference modifier to engrave some text on the actual keyring object, but it seems to be inconsistent in some of the vertical edges/faces.
By looking at the image below you'll see that the vertical edges in the number "1" are previewing in orange meaning they'll be created. Notice the vertical edges on numbers "3" and "5" are black, and will not be created.
I can confirm that after applying the modifier it does exactly what I just mentioned. "1"s are engraved perfectly, but "3"s and "5"s are missing the vertical edges and faces between the bottom of the engraving and the front face of main object.
What am I doing wrong?

I'm having trouble recreating your problem. https://i.sstatic.net/KFYn8.png. But I have had my fair share of Boolean misbehavior. Would you consider sharing your Blender file?

By the way, this might help you: https://blender.stackexchange.com/questions/131035/boolean-modifier-difference-not-engraving-correctly?rq=1 If nothing else the first comment describes how to share a Blender file.


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Texture paint on both sides of a mirrored object?
I was texture painting a mirror modified mesh and wanted to customize the look of the left arm to the right. But, since the mesh is mirror modified it paints symmetrical. I saw online that you can't generate individual UV cords for each side due to being mirrored but you can use the U and V modifiers inside the mirror modifier. Though, when using them I got weird issues where painting on one face would also paint on a random the other(almost like overlapping) when none of the uv maps were overlapping. Is there a way to be able to texture paint each side differently? Thanks.


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Arc Tool / Precise drawing / CAD Style
Is there a way to draw an arc, a portion of a circle, on an inclined face, with a very good precision on number (and position) of segments ? >> See gif (sorry in French)
I'm trying to learn Blender. As a Sketchup user, there are lots of things that seem very complicated to reproduce in Blender. I know this is not the same modeling philosophy, but these things are for me very important to reproduce. I precise that I'm a "precision freak" ;-)
I know Construction Lines Add on, but the arc tool just propose start-end-height options (no center).
Thanks !

Hi :). Perhaps the TinyCAD addon shipped with Blender could help?

Thanks, I don't know Tiny CAD ... i'll check
(I just know "Construction Lines")

Tiny CAD won't do what you're looking for.  Blender's not very good at CAD.

Somewhat related. https://blender.stackexchange.com/questions/133870/how-can-i-create-a-mathematically-correct-arc-circular-segment


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UV meshes not showing ever since update to 2.80
I can't seem to get the default mesh to appear right in the new version of blender (2.8) this is with factory default settings. What could I possibly be doing wrong?

Hello, it's probably a problem with the last AMD driver, you can try an older one or go into the Render panel > Performance > High Quality Normals

Thank you! I couldn't find the high quality normals in that panel, but a driver roll back helped. Inelegant perhaps, but effective.


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Interpolate changing value with animation nodes
i would like to find a way to interpolate values that change each "random" frames.
I can't use FCurve because i don't know the new values and they born from complex function f(obj.location) while the entire animation.
Example: i have
value 5 from frame 1 to 30 then
value 20 from frame 31 to 80 then
value 9.5 from 81 to 102 and so on.
Here there is a file with the example than you can download but there is a problem.
Each time the new value borns there is a flickering in the animation for two frames and then the interpolation is fine.
Anyone can tell me if this approach is the best or if is there a better method to solve my generic goal?
For info the flow of the example in the file is

time starts
when new value (in the file is a new random value) borns a set an attribute of an object
in an second animation nodes layout i trigger the changed of the attribute and i "save" current frame and previous frame in other 2 attributes of the object
the first animation nodes layout can, at this point, assign new value of map range (min and max) to interpolate. the trick is shift max value to the min and assign new max from new random value.
at the same time i reset the value of map range with 0 (current frame - last current frame saved by triggering the random value change).
as a result i have a loop of interpolation from min and max each time the new random value borns.

Thank you very much!

This is not a "full" solution, but it works and i think the "logic" is a bit simpler than yours and easier to understand.
So first there is this "animate object"-subprogram, which takes the object, start vector and an end vector, start frame and a duration and it does what it's called: it animates the object from point a to b from "start frame" on in "duration" time.
I create 3 lists: a list of vectors which are the positions the object is moved from/to. A frame start list. A duration list.
The current values of the lists will be stored in the corresponding attributes.
They will be stored if the frame is equal to the frame list value.
And the subprogram will be called with exact these stored values.
What i didn't do but i think you know how do that:
You have to create 3 randomized lists (instead of my hardcoded ones) which should make sense (so duration should not overlap the next start frame e.g.).
Hope this helped you a bit.
If you have questions, just ask.

result:

Hi Chris, thank you for your answer. I think it is a good solution for my problem, better then mine ;-) I'll try it!

Glad I could help

I was very happy that your explanation in your question was so good that I could write it „on my own“ because to be honest I did not completely understand what you did in your node tree


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Problem regarding fluid domain
While using blender for making water simulation,when I set the physics of cube to fluid domain the cube still remains soild so I cannot see my water simulator unless I turn the wireframe mode on . I cannot figure out the problem . Please help me !

Go to "Mesh" and press "Bake Mesh". This will create a mesh based on the information generated by the fluid data bake. What you are seeing now is only a particle system helping you visualize the fluid and is not meant to actually be used in a finished product.
After baking the mesh is finished, the domain will take on the shape of the liquid, and you will no longer need to use wireframe mode.


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Is a photo editor or vector graphics software essential for 3D creation and Modeling
I am new to blender and I am trying to build my skill. I am curious as to whether learning an addition raster or vector-based graphic software is essential in Blender, as I feel there are some textures that I feel may need. or is it possible to find all I need online? I don't want to spend time learning photoshop while I could be using that time improving my blender skill

There is no such a rule.  In fact there are no rules at all here. It depends on what you want to do. No software is essential in digital art. You can use whatever you want or like and whatever gives you the desired results. With that said it is a fact that photo or image editing software is extremely useful when working with 3d.
Having worked with Photoshop almost every single day of my life for the last 15 years or so I can say... that it does not necessarily need to be Photoshop :D . It's a good and popular choice, but you can definitely find good or even better alternatives. You can choose Krita, Affinity Photo, Gimp or even do some painting straight in Blender, but Photoshop will do as well. Or don't choose at all, use all of them that you can get your hands on. As for you not wishing to spend time on it... Well I would recommend not to think too much about it. You will not waste that time and you should be prepared to spend loads and loads of time if you are learning CG anyway. The main concepts are pretty similar in most image editing software packages and will be useful whatever you choose. In 3d graphics context, image editors are relatively simple, so it's definitely not a bad idea to just choose one and learn it. Don't make a big deal out of it.

I'm really enjoying your answers to these opinion-based questions :). Nothing beats personal experience.

I was having a real battle with myself if I should break the rules here, but decided to just go wild here. :D

Yes. You will need additional tools once you get deeper into 3D, but it will depend on your needs. Some of the tools in blender are quite mature, others not so much. There are no tools to paint, modify or reformat pixel based/raster images in blender, so you will need to use a paint program.
Vector/Curve editing in blender is not great compared to other mature and specialized vector drawing programs out there. It will be easier to work in those first and import curves into blender.
Creating maps, textures and UVs in blender is possible, but there are plenty of more efficient tools as well.


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Where can the backdrop option for blender 2.82 be found for composition?
please where can I find the backdrop in blender 2.82 I cant seems to find it on the shading tab. I have no idea after reading the documentation https://docs.blender.org/manual/en/2.82/compositing/properties.html

That option is for the Compositor not the Shader Editor.

@RobertGützkow bless, what is the difference between the shading and compositor tab then?

in 2,8 they are two different editors, they both use nodes, but for different purposes. Shading is for materials used in the geometry. The compositor deals with rendered images and pixels

The Shader Editor is for creating materials, the Compositor for compositing and editing images. Note that the tabs in the header are workspaces, which use these editors in particular areas of the interface.

@RobertGützkow can you write an answer so that we can up vote it?


text:
Is there an easy way to mirror a pre-existing shapekey animation/action?
I created a series of shapekeys to animate some clothing on one side of the body to make sure everything was right, set up the actions, NLA, etc. Then I created new shapekeys from the mix and mirrored them so that the effect would be on both sides. However, now my animations only run on one side of the body. Do I have to redo the animations from scratch with the new shapekeys, or is there a way to copy the keyframes on the timeline of the old one sided shapekey to my new mirrored shapekey? The only data I need to transfer are the frame and the value.