text:
Crop a moving screen from a video
I am completely lost on how to even word what I want, but here goes.
I have a video clip of someone holding a screen up to a camera, what I want to do is track all four corners of the held screen and crop/transform/stretch it to the entire view. Like a really bad screen grab.
Apologies if this is a duplicate, I have searched high and low and just can't find what I'm looking for. Maybe it's just my wording. Links to any resources/videos that can help me would also be greatly appreciated.
:)

Hmm you want the plane tracker I think but use it to invert distortion back to full screen? Maybe by usnig the UV node?

Okay, so I have done the tracking, and set up the Plane Tracking and I have a box following the screen around as accurately as I am happy with. What would be my next step?

I feel like the corner pin node might get me somewhere. It seems to do what I think needs doing. Just unsure how to get/how I would use the tracked positions of the plane tracker.

Yeah you can't, you'll have to just use the tracker positions. Turn them into tracked empties in the Solve panel. What you want to do is UV map the region bounded by the tracked markers then distort the resulting plane into a full screen. But I tried and have no answers sorry.

Okay, thanks for helping. It's a start regardless.


text:
Change frame color of grase pencil
The Grease Pencil's keyframe color and thickness is quite similar to keyframes of object from viewport. Is there way I could edit the thickness and color of the grease pencil keyframes so it doesn't look so confusing?

All keyframes are equal. In the dopesheet you can manually set the keyframe type for each keyframe, so it displays in a different colour.

source: Stack Exchange

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

sort: votes


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Is there way I can merge all grease pencil keyframes into one frame？
Is there way I can merge all grease pencil keyframes into one frame？So I've seen there is multiframe
option in blender, but it doesn't allow me to copy though, wonder if there is way I can merge all the keyframes drawings into one drawing.

Copy and paste in Edit Mode.
Also you can merge layers in the dropdown menu near layers Merge Down, though there is an issue if the keyframes don't match up

Hi, thanks for the post. This site is not a regular forum, answers should be substantial and thoroughly explain the solution and required workflow. One liners and short tips rarely make for a good answer. If you can [edit] your post and provide some more details about the procedure and why it works feel free to restore it, otherwise it may be deleted or converted into a comment. Perhaps add a few images illustrating the workflow and final results. See How do I write a good answer?

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


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modular frontend support? /new features, xbox controller support?
Both my brother and I have tried to use blender in the past for 3D modeling or animation.  I found the layout/ all the keyboard cammands frustrating.  Lately within the past months, my brother has spent 3 weeks on and off trying to learn from video tutorials on the web.
I had some ideas to make it easier to use...
One thing that may make it easier to use may be if a person is able to use a game controller or other input devices to create animations.  Is this possible currently? not BGE
After trying to work through web video tutorials for blender3d, I eventually used freecad for 3Dprinting and was able to create and print basic 3D shapes.
Is there any way to make the blender GUI feel like freecad?

Blender is infamously know for not being user friendly or welcoming to new users, but I strongly doubt using a game controller to create animations would be any easier.

Please only ask one question at a time. You are welcome to ask as many questions as you need as separate posts.

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


text:
Swap areas using python
I'm new to blender scripting and I'm trying to make a little addon to swap areas, I know, ctrl+click on the editor's corner make this instead of spliting the editor, but the area is very small and sometimes end clicking anything else specially when using multiple monitors.
I'm new to python but learning, now this is the code that I have:
bl_info = {
    "name": "Simple area swapper",
    "category": "Window"
}

import bpy

class SwapArea(bpy.types.Operator):
    bl_idname   = "area.swaparea"
    bl_label    = "Swap Areas"

    def modal(self, context, event):
        bpy.context.window.cursor_set("HAND")

        if event.type == 'LEFTMOUSE':
            print('swaping areas')

            # bpy.ops.screen.area_split(direction='HORIZONTAL')
            bpy.ops.screen.area_swap('INVOKE_DEFAULT')

            bpy.context.window.cursor_set("DEFAULT")
            return{'FINISHED'}

        elif event.type == 'ESC':
            bpy.context.window.cursor_set("DEFAULT")
            return{'CANCELLED'}

        return {'RUNNING_MODAL'}

    def invoke(self, context, event):
        context.window_manager.modal_handler_add(self)
        return {'RUNNING_MODAL'}

addon_keymaps = []

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

    wm  = bpy.context.window_manager
    km  = wm.keyconfigs.addon.keymaps.new(name='Screen')
    kmi = km.keymap_items.new(SwapArea.bl_idname, 'SPACE', 'PRESS', shift=True)

    addon_keymaps.append(km)

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

    wm = bpy.context.window_manager

    if wm.keyconfigs.addon:
        for km in addon_keymaps:
            for kmi in km.keymap_items:
                km.keymap_items.remove(kmi)
                wm.keyconfigs.addon.keymaps.remove(km)

    addon_keymaps.clear()

if __name__ == "__main__":
    register()

If I run the code to split the area it runs fine, but when running bpy.ops.screen.area_swap('INVOKE_DEFAULT') nothing happens as far as I see in the API docs, this method doesn't take any param to indicate which areas will swap. I'm getting lost with it, so if someone can give some help.


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Transparency doesn't work (Cycles)
I tried to Render my Picture with a transparent background.
Without transparent background it works fine, but with there's just an empty transparency. I checked my compositing Nodes and I checked ''Use Alpha'' everywhere.
Here's the file and I hope somebody can find the problem.
https://www.dropbox.com/scl/fi/yb20indgoo0ytj43zn4en/Karate%20Feuer%202.blend1?dl=0&oref=wn&r=AAkBychaZdNTj3mYiYbUNkL9HH9-5nvpqg0_Cmf24Mn0vanH9M79oGJ2w5Z6yg7HARZE_EcBsMs7KazCatDo0pLNnv3P7foaKPJ9drS8jFu0HMNV_nxAtRB2yp5CkkDvNPN6nRQQwx_jrxoFemGBYfMSJo52FGKeblcS-2atpeG2YvtgangWrXPY66aKa7phi8U&sm=1

Please use https://blend-exchange.giantcowfilms.com/ for blend files. Also, while it can be good to have a blend file to look at, we would ideally be able to solve the problem without having to download a file, by having a well described question with pictures.

The setting you want is in the render layers tab:

Unchecking this box will give you a transparent background instead of rendering the sky/environment map.


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color glitches and weird texture in render
When I look in my preview render everything looks fine (for not having finished lighting) but when i actually render it the color of my doughnut icing glitches and the texture of the table doesn't appear.

It looks to me like you have some extra lights and meshes in your scene that are hidden in the viewport. Objects that are hidden in the viewport won't show up in the preview renders, but will show up in the final renders. You can reveal any hidden objects by using AltH. Then once these hidden objects are revealed you will be able to see their effects in realtime and remove or adjust them accordingly.

Your table material may be suffering from too much specular.


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About molecular add-on in Mac
Im making some simulation in blender and get interested in molecular add-on. but it is not working in my computer. I'm using Mac Pro(10.13.2). And the blender version is 2.79. Someones says that add-on's version dosen't be a matter even if the blender is 2.79. But I couldn't find any information  about to add the add-on to Mac. I mean that I tried few times as Win's way but I failed.
 The add-on is downloaded on this website.(http://pyroevil.com/molecular-script-download/)
If you have any information about it, please help me. Thanks.

You don´t need to copy only the folder "addons" and the folder "molecular", if you try to copy both files that are in the folder "molecular" you can't install the addon.

Don't forget that Macs tend to decompress zipped files upon download. You may need to recompress the folders

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


text:
Blender python array modifier transforms
Can one get (in python) transform properties (location, rotation ect.) of the objects created by the array modifier?
(while the array modifier is active, without applying it)
I need to be able to snap some other object to one of the array duplicates
thanx

Doing that implies recoding part of the modifier in Python (eventually taking into account other modifiers in the stack)... so if your situation has some specific parameters for the modifiers you should explain it in the question (as a generic recoding of the array is not a so simple thing).

Whatever geometry array modifier creates it's not exposed to API as objects as far as I can tell. But you are able to snap to array-created geometry through vertex / edge / face mode as with the original mesh.

An exposed api would be nice... as the api is probably not exposed (why?), I guess I will have to find some other workarround. Ijust need the locations and rotations of the objects.
snap is not the right term to use. I need to get other objects to the locations of the array objects programmetically.
any link to learn about that array recording thing?

@gnotev, technically speaking, array modifier does not create a sequence of separated objects. It creates additional mesh parts which are inside the same original object. So from the array modifier result, there is no simple way to retrieve these mesh parts. The only way is to recalculate all from the original object and the array parameters (but as I said above, you need to provide more information to see if the calculation is possible or not)

I'd say this is quite do-able.  Being a modifier, it does create the arrays as one mesh, but in doing so is calculating the local coords of each copy, Suggest grabbing  the c source code and emulating  in python.  As stated previously would only need to create an array of matrices each having the transform of array instance.

Emulating the c source in python is too complicated for me now. I wanted to use the existing modifier's power to find the positions i need without having to calculate anything. I wish there was some kind of api or the resulting transforms were acessible. I suppose it is up to the modifier's programmers so i will try to find a wishlist for a later version perhaps. Thank you all !!!

a quick and dirty way would be to copy the mesh apply the modifiers do you calculations on the results and then delete your copy.

yep that crossed my mind... might have to do that

Using modifier array, e.g.:
def array(self, obj):
    mod = bpy.data.objects[obj.name].modifiers.new(name='array', type='ARRAY')
    mod.count = 10
    mod.relative_offset_displace[0] = 2.5

position and rotation can be calculated from the formula, e.g. 5th element in array would have x = 5 * mod.relative_offset_displace[0], so if original is [0,0,0] then 5th will be [6.25,0,0].

mod = obj.modifiers.new(...) Related


text:
Why does my camera start rotating randomly when following a path?
I have a camera that follows a bezier curve with a Follow Path constraint, with a Track To constraint that follows an object (named "Viewer") moving on another bezier curve with another Follow Path constraint. Everything works out perfectly fine with the camera's rotation for the entire path, until this part where the bezier curve does a loop. Once the camera reaches towards the top of the loop, the camera just rotates randomly, and no longer looks at the object. It still follows the curve, except refuses to look at the object which it's supposed to track. Once it reaches the bottom of the loop, everything returns back to normal. I've already tried clearing the curves' tilt. What am I doing wrong here?
As you can see in the picture below, the camera is facing down, when it's supposed to face torwards the object (you can't see the object since it's only a single edge).

Please download the .blend file, my explanation might not be enough for you to understand. Just enter the track camera view and play the animation from the beginning. Once it reaches the loop, you'll see what I mean. I appreciate any help in advance.

A quick fix can be as follows:
Select your target object edge (Or duplicate it). Press P > Separate by Selection which will create a new object. Select both objects (Your old object and newly created object)
Hit Ctrl+G to add both objects in a group so that they move as a single object.
Now you may lock the camera view to your new object.

I removed the "Copy Rotation" constraint on the camera and it seems to work fine. You are copying the rotation of the Viewer object but I don't think it's actually rotating, so in the loop it confuses the camera.


text:
Textures are missing (colored magenta) in Material Preview, yet show up in Rendered View
I have a model that I'm overlaying several images over. Each of these images are texture-painted masks and, through a mix shader, are being assigned different textures - all within a single material.
This has caused an issue. I like to texture-paint in Material Preview mode; however, in that mode, the model turns magenta as if the textures are missing. I've packed the textures, saved them to another location, restarted Blender multiple times, yet they still appear magenta.
The strange thing is, when I switch the viewport over to "Rendered View", it appears with all the textures on it. I can also render the scene and the textures appear fine.
Material Preview:

Rendered View:

TLDR: Model appears magenta in Material Preview, but show correct textures in Rendered View and final render, despite the textures being referenced correctly (I hope).

Engine: Cycles
I have 1 UV map on the model.
I've painted with the "missing" textures working before. The problem arose when I added another blank image for more texture painting. Yes, that one is saved to my computer/packed in the .blend.
My normals are facing the correct way.

Hi, try to show your shading node setup also.


text:
How to mix 2 keying nodes in the compositor to keep the alpha channel from both?
How do I mix two keys in the compositor to form an image that uses both the keyed out parts?  Movie Clip node > Keying node > Viewer = green screen removed; then same Movie Clip node > different Keying node > Viewer = blue markers removed.  How do I combine these?  I am trying to remove the background, and isolate the people in the foreground and have an alpha channel background.
edit: I don't really know what to search for, can anyone maybe share a link or just tell me the words to search for in Google?
Do I need to render out 1, then go back and re-render out the second?  I feel like there is a way, similar to render layers, but with images/movies, sorry if this doesn't make sense, I will edit it when I can.

put one into the other as so - that way each node changes the previous

It doesn't seem to work with the Keying node.  Adding the second Keying node just seems to change the color of the background more than key it out (like it is when it's solo).  I am about to try that with the color key nodes though, thanks.

Using the color key nodes got it very close, but I think I'll have to use the keying node and render out a sequence and then re-key out the other color and render a second time; the keying node seems to work better for the different shades of color/shadows/ movement/etc., than the color key node. TY for the reply, I might end up using your example, still testing stuff out. : )

Did you work this out @Policestate. I'm trying to do something similar in that I've isolated all the elements I require, and I want to then combine those Keying nodes into a single output-able stream.

This does not really answer the question. If you have a different question, you can ask it by clicking Ask Question. To get notified when this question gets new answers, you can follow this question. Once you have enough reputation, you can also add a bounty to draw more attention to this question. - From Review

No it doesn't, but I lacked the reputation to simply comment as a new user. Happy for this to be moved as a comment to the thread above.

Note to self, I should search through the other nodes types for the following: Merge
Layer
Combine
Add + Max + Plus : Scene


text:
How can i reduce the size of my shadows?
I am lighting my scene with an spherical environment map. As you can see in the image below, the shadows casted on my shadow catcher are way too big. How can i change this?

first make sure your background map is in hdri format. Then try adding a colorramp node and squeeze it, connecting it between the output of the map and the input of the background material.

you could make it so that the background is not the light source with this node setup
Then add a sunlamp, with it you can either increase your lamp's strength or decrease its size
A smaller lamp size will give a sharper shadow

then change it so it matches your background's color and thats it.
here is a more detailed answer to your questionn
How to minimize/soften the shadows?

Thank you for your answer. Sadly your trick didn't really work. Now my scene is really dark and the shadows are still all over the place.


text:
Beveling - Why won't old edges go away?
I'm brand new to blender and have been trying to teach myself for the past few days, but I keep getting thrown by the simplest things. In this case:

I've beveled this edge, but the old 90 degree edge is still there. I can manually delete all 5 pieces of it, but it's super annoying to try to grab those tiny pieces.
I'm using version 2.78 on a mac, but the same thing happens in 2.79:

Would really appreciate some guidance. Thanks!

Have you by any chance got Bounds > Box switched on in the  Properties>Object>Display panel?

hmm, no. i have the feeling it's something very obvious that i'm not experienced enough to think about, though...

Shame it's not that one.Maybe share your file, or the representative bit of it, at https://blend-exchange.giantcowfilms.com/

To me it looks like you have duplicate vertices, try select all and remove doubles (now called merge by distance in 2.80)

Not sure what is happening, but I do know that you do not have to select EVERY edge.  If you just grab each corner edge, you can hit delete and select vertices from the drop-down.  This will result with the other edges being deleted as well.


text:
Blender Freestyle in depth control
How can I control specific edges I want to have an outline? I know you can make a freestyle edge mark and exclude them but there doesn't seem to be a way to edit it more in depth like choosing one edge to have an outline and another without in the same mesh object. I was just curious if someone has made an add on for blender freestyle that gives you more control like that.

If I understand your question, this is native behavior. Freestyle edges can not only be excluded, they can also be included. And you can include ONLY freestyle edges if you so desire.
This setup does it. I removed all edge types but edge marks:

My question is can I include certain edge marks and exclude others for the same object?

I doubt it. Edge mark indicates the edge you want to be considered as an edge mark. If you don't want it drawn, you don't include it into edge marks. If you want all edge marks to not be drawn, untick the option in Freestyle.


text:
Make light paths only pass through non-emitted areas?
I'm trying to make it so that the plane is transparent except for the light from the aqua emission. Or in other words, how can I make it so that the plane's white areas are transparent and the plane's aqua areas are not?
I want to achieve this without using the compositor, only with material nodes.

You want it for a still render or animation?

@PaulGonet Animation

For still you can bake the emission and use it as a mask and for animation I'm affraid it is doable only by using compositor.

Is your goal to have the reflections be a light beam effect? You might be better off using volumes instead.

As far as I know this is fundamentally impossible to achieve in Cycles.
Cycles being a physically based renderer has to find a solution to the rendering equation, this includes calculating all lighting interactions influenced by surface properties. Materials can't possibly depend on the render results; so surfaces properties can't be influenced by the render solution.
As such transparency, emission strength or any other material properties can never be the result of light intensity hitting that material, because it would cause a dependency loop in rendering process. You can't determine surface lighting before you know its transparency, and you can't set its transparency without knowing the light intensity.
So either fake it in the compositor, bake the light into a texture, render in separate layers and separate steps, use a Shadow Catcher material (only available in 2.79+ versions), or change render engines and use something non physically based, or non photo-realistic.
EEVEE being non physically based biased render can use a Shader to RGB converter node that can use light incidence as output to influence material properties.
If you have a single light source in your scene, or if lighting comes mainly from a
single direction, you can use other tricks like using a lamp object position as directional material input.

Alright, thanks for the answer! I'll find some alternate way, I'm sure.

Very clear explanation. I have the same thoughts (explained it in my comment). +1 from me. @Squirrel You won't find an alternate way unless you use the Compositor ;P.

@PaulGonet Actually I meant find some alternate way to use emissions like not use emissions on the ship or something like that (model-based)


text:
Offset Camera to Local Axis
I have a road with a plane locked to it through a curve and a constraint. I also have a camera that's locked to the plane with a Copy Rotation and a Copy Location constraint. However, when I enter the camera view, the camera goes inside the road, meaning I need to move it up. However, when I move it up (Z axis) and the camera approaches a bank turn, the camera goes way off the screen. So what I need to do is move it on the local Z axis. I've tried using the Limit Location constraint, but even when I set it to Local Space, I still have difficulties trying to get it to move on the local Z axis. Is there a way I can offset the camera so that it doesn't have this problem? Here's a picture representation:

Thanks in advance if you can help!
Here's the .blend file:

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

That seemed to work! Thank you so much, it helps a lot!

@Grant I would also add another plane (or an empty) to go in front of the one linked to the camera.  You could have the camera point toward that plane's origin.  So if you went around a corner or crested a hill, the camera would always be "looking ahead".

Alright, I'll go ahead and try that, it seems like a great idea!


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Graphics Tablet not working only in 3D View
I have a Huion Q11K graphics tablet. Only the stylus pressure doesn't seem to work. I can use the pen to click on menu buttons and manipulate the view just fine. In fact holding shift while sculpting works with the stylus for smoothing. Only pen pressure in the 3D View doesn't work.
Also with ScreenCast enabled the pen registers a left click but has no effect.
I've spent a few hours looking for solutions but it seems that no one else has ever had this problem... So I'm hoping it's something stupid that I'm missing.

In your brush settings you need to hit the  pressure icon on the right of the slider. The slider then defines the range that the pressure of your stylus is mapped to.

Thank you for the quick reply. And I was sure it was what I was missing but it still doesn't work.  The other thing to note is that it works, with pressure, if I hold CTRL, but 'Add'itive. Whereas I would expect it to be Subtractive. So... If I don't hold CTRL the mouse left click is additive and the pen does nothing; If I hold CTRL Left Mouse is subtractive and the pen is additive.

very strange, my Huion tablet worked right out of the box so I'm not sure how to help

Okay, got it fixed. Not 100% sure, but I believe the problem was caused by Windows Ink being disabled. I had disabled Ink in my quest to get my old monoprice tablet fixed. I tried re-enabling it but I couldn't get it to show up in the tray. Due to an unrelated issue, I had to re-install Windows which fixed everything. So, it was either Ink was missing or something was not right in Windows. Note, prior to re-installing Windows I had uninstalled and re-installed both Blender and Huion drivers to no avail.


text:
Start an animation nodes TimeCode Generator at a specific point
Does anyone know how I would START a timer at a specific point?  I will need to use the timer between many scenes, and I need it to pick up where the previous scene left off....
Here's what my timer looks like:
It is in days:hours:seconds:milliseconds format. In the next shot, I would need it to START at 00:00:03:15.  Here is the uber-simplistic node setup:

Any suggestions?

Adding n to the time will offset the time n number of frames:

thank you Omar!  Just getting started with animation nodes!  Thanks so much!


text:
Will there be a browser version of Blender?
I heard about WebAssembly, which lets C/C++ programmers target the web, I was just wondering whether Blender has any plans to make a "web" version, that runs in the browser? At the recent Google I/O, they showed AutoCAD running inside a browser using WebAssembly, so...logically, Blender should follow suit...?
After searching, I see that B is written in C and Python, and from some searching, I don't see that WebAssembly can do Python yet - maybe someone should get in touch with them?
And just to say - I have no idea WHY I want a web Blender, it just.....seems cool! :) Other projects in this area have already started - check www.tinkercad.com !

I'm voting to close this question as off-topic because it is speculation about upcoming features

"so...logically, Blender should follow suit" That doesn't seem very logical to me; there are no known plans, as far as I can tell. Honestly feel it is a waste of time, there are far more important and useful things to keep the few developers busy for a long time. That being said Blender is Open Source, nothing stops an interested third party from porting it.

Godot recently ported their engine to the browser, and as justification they had 2 relevant points: (1) "It will lower the barrier for new users, which will be able to try out the engine without the need to download anything." and (2) "It will allow to use Godot in a reasonable way in environments where installing/downloading applications is not an option (e.g. schools’ computers and tablets), fostering the usage of the engine for educational purposes (which is something we, as an open source community, deeply believe in)."

No. For questions about the future of blender, check the roadmap here: https://code.blender.org/2013/06/blender-roadmap-2-7-2-8-and-beyond/
There are no current plans for browser integration.

Given that the wasm-gc proposal is moving along, and WebGPU is already hitting browsers, it seems like the next few years may offer some surprises in this area. Of note is Godot's recent experimentation with a browser port. At the very least I'd expect an attempt at an unofficial port some time after wasm-gc lands.


text:
Cutting a Soft Body in Game Engine
Is it possible to cut an soft body (such as a jelly sphere) in game engine mode using a 3D cursor (as a knife)?
I'm trying to animate a jelly in the scene, that can be cut in play mode using a knife as a 3D cursor.


text:
Export obj from Blender keeping position
I'm trying to model some things for Poser.  Whenever I export the .obj out of Blender it ends up on the floor in Poser.  I'd like it to keep its position.

Where is the origin of the obj? Poser likely places the origin at the center of the scene, so make sure the origin is at the center of the blender scene before exporting (Ctrl+A and apply location should do the trick).

That still brings it into Poser on the floor.  :/

Post some screenshots and a as-simple-as-possible blend file that shows the problem.

http://anniemation.com/blender1.jpg

http://anniemation.com/blender2.jpg

See how the glasses are on the head of the model in Blender?  But when I export them to poser they end up on the floor.

I got it figured out.  Needed to un tick the centered in Poser import.


text:
How to make a tree leaf a solid color depending on how much light hits it (eevee)
Is it possible to make each leaf of the tree a solid color from the colorramp depending on how much light is hitting it?
I've done a data transfer on it to copy the normals from a sphere to give it a more anime look but it'd look closer to the reference if each leaf didnt have cel shading on it and it was just a solid color as if you were using a paint brush and just doing little dots for leaves lol
(also dont mind the different color ramps i was just playing around ^-^")

I think you have the right idea - one thing you could try is to disable shadows for whatever light source you're using - let the toon shader handle the "shadow" effects. That way the leaves change their shade based on how shaded they are from the light source, but don't receive shadows from other leaves which would cause their subsequent leaf colors to become non-uniform:

The material I used is almost exactly the same as yours, for reference:


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Randomize the UV of an object with an array modifier?
Can I randomize the UV of an object with an array modifier I'm try to make stairs using an array but with same uv texture, I don't like how it looks.
[?

Try U-Offset/V-Offset in Array Modifier.


text:
how to put a object in blender in focus? Viewport focused on the Selected Object
how to put a object in blender in focus? Viewport focused on the Selected Object
i click on emultating mouse pad, saved changes. everything works besides the "period" to focus, idk what im doing wrong
https://www.youtube.com/watch?v=JYj6e-72RDs
10:13-10:38
can anybody help me?

i want to focus on the selected subject so that its in frame

You want to pivot around an objects origin, that is what you want, not focus, you are not talking about the camera

Are you hitting period on the number pad? If your keyboard doesn't have a numpad this thread may be useful in remapping the key:
Emulated Numpad Mapping - Numpad Period?

yes hitting period on the number pad. but i dont have one so i select "emulate number pad" and then i click "." on my camera to focus on it as a short cut while i have it selected. but it does nothing. also im not sure what the function is called so when i try to remapping the key i get lost, because blender has so many setting function names and shortcuts. so i am not able to locate the function to be able to remap

The function you are looking for is View Selected. It can be found in the Viewport in View > View Selected, or via spacebar/F3 search. You can change the Shortcut but right-clicking that button and selecting change shortcut.
Also Emulate Numpad seems to only work with the numbers and the - sign for me. I am using a german keyboard layout so that might be part of the problem


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Orient animated camera horizon to object Y axis
I have Empty in scene center and camera as a child to this empty.
Camera always look in center of scene and 2m far from this center.
In center i have long Y side object.
I "tilt" camera by adjusting Empty Y angle. And rotate around center of scene by rotating Z of empty.
Is this possible using constrains made camera horizontal (Y) orientation always horizontal to this long object?

I found solution.
Locked Tracking to Empty moved along object Y angle.

Awesome, probably add note -to move empty along Y axis from centre (that took me a while to discover what caused the crazy shake) :)


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EEVEE doesn't render textures
I can't find out, why EEVEE won't render my textures (third image). I created the UV map and assigned the material to the Object. Render Preview (first image) shows the texture, but final rendering with F12 doesn't. When rendering with cycles (second image) it is rendering the texture, but it still looks wrong.

You are right, i thought EEVEE wouldn't render it when hiding it in the collection...
Thank you very much!


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orange artifact moves with screen
i was trying to bevel something and this orange speck appeared when i ctrl z back. i cannot get it to go away and reload its still there it does not show up in a new file, it looks like 3 pixels, but it stays relative to whatever view. when i move my view it stay exactly in the same spot in the screen view, so i don't think it is anything in the scene. not sure what did it or how to get rid of it, i looked around on here and other online places but cant seem to find out anything? attached is a pic sorry both screen are on the screenshot im new to this, and the artifact is near the handle, it is not an origin dot

What happens if you close Blender and reopen a new session?

Try tabbing into edit mode with your handle object. You may have accidentally added an additional floating face to that object, so if it's still there in edit mode, select it and delete it.

now its not there, a new file does not have it and it cannot be deleted. However now there is a white plus sign+ exactly where the speck was. dont know if its related? when i put my cursor on the plus sign it changes to a crosshair and has a x on it also and moving over to the corner of the plus shows a corner boarder. edit i can move the plus sign though


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Sequential channeling in Node Editor (no PBR workflow)
I'm trying to make a functional sequential channeling/masking without any external media. To make my point clear, I made this quick .blend where a traffic light goes to red > yellow > green when the input value rises.
This is the effect I've got so far:

This is my node setup:

And this is the desired output:

I know that in a PBR workflow I could just make an image for channeling/masking the output colors via UV mapping, but I wonder if I can achieve the same effect without external data
Objective:

Achieve the desired sequential effect with different color output on each element (see example above)

Rules:

No external media or UVs for channeling/masking (PBR workflow)
No external add-ons or plug-ins
No animation/keyframe use

Extra points for:

Optimizing node setup
Finding and explaining a better way to achieve the desired effect
Is there a binary value input? like an ON/OFF for each individual element instead of setting a math conditional by numeric values?

Thanks in advance for your help!
Edit: here's the original .blend file

Nice topic :) BTW Isn't that like only one light should lights at a time?

You can use "texture coordinate" input node and a "color ramp".
The X output is between 0 and 1. So if we split the color ramp in three constant steps at 0, 0.3333 and 0.6666 we'll have the color we want for the good disk.
For the grey part, we just compare the input value (0, 0.1, 0.2, 0.3) to X clamped into 0 and 0.3.

Nicely done and way more elegant :).

@JachymMichal, thanks... have UV yours as the OP said "no UVs"... ; )

Yeah, I must've missed that part :).

This works and meets the question requirements in a very elegant and simple way, I'm voting this as the solution to the question, thank you for helping! :)

I couldn't help noticing an unsightly wipe in @lemon's answer, so here's a variation on it that switches.

..I'm sure this is what he meant ..

Certainly, but he said "No animation/keyframe use", so considered this does not matter...

@lemon .. Just kidding, I would not have thought of your way in a hurry :)

unsightly... I didn't even know that word 5 minutes ago : )

This works and meets the question requirements very well. It's a little bit weird those value increments, but thank you for helping with this variation and reaching the objective! :)

@ermac .. a couple more nodes would set the values to whatever you like :)  I'm releived you accepted lemon's. this is basically his answer.

After the good answers and suggestions, I've made my own answer with some additions to whoever wants more features with this workflow idea.
Here's an optimized output (inspired by all the proposals received):

And the optimized node setup:

Explanation:
Four math nodes in total function as the masking factor and it's suitable for extending the object count and its values. To achieve this, the light lamps are now individual geometries (they are not into the same mesh group) and they were assigned with a different Object Index (Object Properties > Relations > Pass Index) to each one. Having now a unique index identification, it's now easier to control which element (or elements) changes sequentially when the value input increases.
Usage:
You can now add more mesh elements and features to change sequentially

Separate the mesh or add a new geometry
Delegate an Object Index number to each geometry
Add an extra color in the ColorRamp or any feature you like
Change the Modulo value to match all the Index numbers
Subtract 1 Index number from the total in the Divide node

By following these steps you can now control the sequential output using only just 1 click with no UVs or external masking media :)
Extra idea:

You can delegate the same Object Index to different geometries if you want them to have the same output when it's needed (for example: making the 3-2-1 countdown all in red and the GO! light in green). It's not necessary to have 4 colors to achieve this, you can just put Red and Green color in the ColorRamp and delegate the same Object Index value to each 3-2-1 sequence. Don't forget to update the Modulo and Divide values according to the total Index values.

Hope you find this useful and I hope you learned new things as I did today. New suggestions and alternatives are always welcome.

Simply add a Gradient texture with a UV map to your setup.

Create a UV map for the traffic lights. (UV > Project from view)
Add a Texture Coordinate > Gradient texture > Color Ramp for each phase
The ColorRamp (set to Constant) controls which lights are on/off during the phase

Connect it to your current setup.

This works although it doesn't meet the question requirements, thank you for the alternative approach :)

You're right, I should learn to read more carefully :). Good luck with your project.

No problem, thank you for your wishes and good luck as well!


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Visible fireflies using object's Texture Coordinate
Making a simple procedural metal shader using a Noise Texture node linked to a Normal Map effect from the object's Texture Coordinate, I've come across this particular issue:

When I change the Normal Map value there's a very visible firefly that appears in the mesh, affecting the texture in some particular areas.
My first thought at this was that I had a Face Orientation or Duplicated Vertex issue. But to my surprise, all the Face/Vertex Normals seems good, and there were no duplicated vertexes.
See mesh analysis:

My node setup:

At this point, I knew that this issue went far beyond my acknowledgments, and this is what I've got so far.
Objective:

Find the property or the mistake I've made that brings this particular issue.
Notice if this is a Texture Coordinate bug from Blender with no troubleshooting so far.

Things I've noted:

When the Normal Map value is 0 this issue disappears.
All mesh normals are facing their correct direction.
There's no duplicated vertex or faces.

Rules:

This shader must be procedural for further use in different objects.
Texture coordinate must be plugged in Object input.
No UV maps dependency or mesh wrapping.

Extra points for:

An alternative solution to make this procedural shader with no UV map or not depending on the object's Texture Coordinate.

Thanks in advance for your help!
Edit: here's the original .blend file

I may miss something that I don't understand but I don't see any reason to use a Normal Map node if you don't plug any normal map image into it?

What I want to achieve with this is more like a superficial stain effect than depth. That's why I choose the Normal Map node over Bump. I might be wrong on this, I'm not an expert in the shading vectors field.

You can have a superficial effect with bumps, it's all a question of settings, but I'm trying to understand your setup, Normal Map needs normal map image to work properly


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What it makes a 3D model game-ready?
I've been up to Blender since mid 2016, started to work professionaly selling my 3D models since Jan, 2018... and now I'm used to hear the same questions from the customers: "Are your models game-ready?"
And I always reply: "By the moment all my models published are not 100% optimized for games"
I say this because I do use PBR materials, modelled mid-poly with tris, and now I'm learning to get my new models rigged and ready to animate. But I think something is missing.
The principal question is... what it takes to make a model game-ready?
do I have to use Blender Game Engine to achieve this?
In college, they taught me how to use Cycles only, and I don't know if a model with mid-poly tris, PBR materials and properly rigged for animations makes it "game-ready" altough it was made entirely in Cycles engine.
a "game-ready" model bought from a digital store, makes it ok for commercial licencing? this is a polemic question, but some customers ask this in some situations. For example: imagine that I make a 3D game-ready model of a Fender Stratocaster guitar, and sell it on internet via a third-parties 3D gallery. That model can make it into an actual published lucrative videogame using the brands and models I've made?
Thanks in advance for your support.

It's a marketing term, like "lite," empty and unregulated.  But yes, reasonable vert count, textures (probably some kind of roughness map, metal map, albedo map, tangent space normal map) on a single in-bounds UV, rigged with standardized skeleton like Mecanim, all non-armature modifiers applied (because games probably don't have shrinkwrap or lattice deform), not going to give draw order issues from alpha.  BGE has nothing to do with any of that.  Licensing questions are a different matter entirely, and this isn't the right stack exchange for them.

Game-ready means that the model could be imported into a game engine like Unreal or Unity without much fuss and that it would render in real-time (>=60fps)

@DuarteFarrajotaRamos only by its title, into the post I'm discussing a different situation.

just curious, what college was it that was teaching cycles?

@David it was at the UTN-INSPT (Universidad Tecnológica Nacional - Instituto Nacional Superior del Profesorado Técnico) in Argentina.


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Texture along the shape of the mesh
I have been looking for a solution to this problem for a long time, and getting to this was my last alternative. I intend to correctly texture my mesh as the image below:

As you can see, it is an every day situation but I would like to know how to solve it in the best possible way without making an extensive mapping of the figure that forces me to make a larger UV texture image in every sense.
I tried many ways, but I did not get the desired effect. I think that my biggest problem in this situation is that English is not my native language, and therefore, I have difficulties to find the exact search title of my problem. (please consider this before mark my question as possible duplicate)
Thank you very much for your help.

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

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


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Some of the faces of my model are are dark
I'm currently creating a car in Blender using blueprints, but I have a problem. Some of the faces are dark and don't interact with lighting.
I thought that I have this problem, but sub surf don't work for me.

Ok, I don't know how to thank you. You really saved me.


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Using Materials with Geometry Node Modifier
Since experementing with the newest Verison of Blender (2.92.0) I work heavily with the Geometry Nodes. But the documentation is very low quality. I was able to model different objects and join them together with the Geometry Node Modifier, to make a bigger model.
Now I have assigned Materials to the single Parts, so I have more control over everything. The Materials don't seem to be moved over with the Object Info node. Is there any way to get the Material to a new Object, only with Geometry Nodes?

yes you can do it in 3.0 Alpha with the Material assign node.
like this:

what version of Blender is this node in, I don't see it in 2.93.1, 3.0?

It is in 3.0 alpha

Okay in 3.0 it's in. But there is no option, if I still use 2.92 or 2.93.1?


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Change an Object's Material to another Material with Python [Pic Attached]
I have an object named "Paper_obj"

After entering the Material tab, there are tons of materials within, "White Transmission", "Steel Mag", etc.
My main purpose is to change the "PaperTopYellow" to "PaperTopRed" by clicking on the drop down list. Can it be done with Python?

Since there are many other objects in the blend file, the hardest part for me is to first target that "Paper_obj" first and then change the "PaperTopYellow" to "PaperTopRed" within.
Thank you!

bpy.data.objects['Paper_obj'].data.materials[3] = bpy.data.materials['PaperTopRed']

The above should be the general answer.
However, what if I do not want to use the slot number but would like to target "PaperTopYellow" and replace it with "PaperTopRed"?
Sometimes, the slot number for "PaperTopYellow" may not be 3 but 2 instead.


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Procedural Material Connecting
I have small procedural circles on a sphere and I want them to connect from their center to the other ones centers in straight lines, Imagine a planet like Coruscant, is it possible to connect them?


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Comfortable Working of Selection Tool
After changing the hotkey "Selection" tool began to work by clicking the Left Mouse Button+Ctrl/Alt (Select/deselect). I'm just fine with that, but there is one catch:
If use the Border Selection outside the object (LMB+Ctrl or Alt) this tool is working correctly, but if using it  within a object, before created selection is cleared.
For example:
If I need to add additional polygons to the current selection
1)

2)

What I need to change or add to this tool works correctly within the current object and  active selection is not reset?
Current HotKey:

There is probably nothing wrong with your border select key definitions, its probably the Select/Activate operator that is resetting your selection. Try change it to either to a Mouse Release event or to Extend Selection by default. This is very likely a limitation of the current system I've bumped into in the past myself

@DuarteFarrajotaRamos Would you like to post that as an answer? R_M_S, when he does, make sure you accept it.

Certainly, posted bellow.

There is probably nothing wrong with your Border Select key definitions, its probably the Select/Activate operator that is resetting your selection.
Try change it to either to a Mouse Release event or to Extend Selection by default, so there's no conflict and starting a border select won't unintentionally trigger the colliding operator.


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hole or not hole in prepared mesh for 3d printing?
I´m looking at many tutorials on preparing things to send as .STL to a printer, but I keep on having the same doubt:
All the tutorials say that, in order to save money, you have to make a hole in the mesh so that the program interprets it as hollow, but at the same time the program wants you to have a totally closed mesh, so it is "manifold".
I really don´t understand how can I do a manifold mesh and leave a hole in it at the same time to be interpreted as hollow.
How is it done? If any of you know any tutorial where they explain it well, it would be a good answer also.

As someone working in 3D printing, I can tell you that those tutorials are wrong, and making a hole inside a mesh to make it 'empty' inside is only going to create troubles.
Basically, to 3D print, your STL file goes through a program called a 'slicer', which will analyse and slice the mesh in layers before sending it to the printer for the actual printing layer by layer.
When the slicer analyses the mesh, it will identify the skin/walls of the mesh, determine what is outside and inside, which will also help it determine if supports are needed or not.
If, for example, you want to print a cube, making the mesh hollow inside means that the slicer will add support for the internal roof of the cube, support that you'll never be able to take out because it's a cube, and you cannot reach inside unless you break the cube open.
Plus, having mesh with 'holes' inside can sometimes confuse the slicer, especially if the walls of the mesh are thin, and prevent it from correctly interpreting what is inside and outside, or mess with the layers.
Besides, making a mesh empty is useless because all slicers have a setting called 'Infill' which determine the shape and percentage of the internal structure. Depending on your mesh, and how confident you are in the material being used, you can set it to 0%, meaning the printer will only print the walls of your mesh, up to 100% if you want to print a solid block.
So, to sum it up, making a hole inside a mesh is a bad idea, it will create problems, it won't really save you money nor time, especially since there is a setting in the slicer that does the same while ensuring proper printing.

That is indeed misleading explanation, by "making a hole" the author probably means making it hollow, but not paper thin.
That means turning the object into a "shell" with an unspecified but non-zero thickness, making it manifold, but not solid.
Quickest way would be to use a Solidify Modifier, but it may not work well on all cases, like complex meshes, intricate details, tight curvatures or other discontinuities.
See Adding thickness to a mesh in Blender, otherwise you may have to do it by hand.

I see... so you are saying that, in order to set the mesh right for printing, what I need to do is use the solidify modifier (I´ve already applied it in the mesh) but no making any hole. With the solidify modifier applied in a totally closed mesh is enought. Is it? (thanks a lot for your answer)

(by the way, they do say that you have to make a hole in the mesh for the printer to know that it is hollow. I don´t know if they are right or not but they do show that in their tutos)

The hole is probably to let air escape or some other structural  purpose specific to the 3D printing technology. You should follow their recommendations. I'm not into 3D printing and obviously haven't read any guidelines you are quoting.


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Is there an equivalent of a cage for Blender Internal Render?
I see in Cycles, there's the option to use the cage during a bake.
Can you also use it in Blender Internal Render?

No, there is no option to use a custom cage for baking with the Blender internal engine. The closest you can get is the "distance" setting, which will sort of simulate a cage.
From the Manual:

Select to Active
Enable information from other objects to be baked onto the active object.
Distance
Controls how far a point on another object can be away from the point on the active object. Only needed for Selected to Active. A typical use case is to make a detailed, high poly object, and then bake it’s normals onto an object with a low polygon count. The resulting normal map can then be applied to make the low poly object look more detailed.

Usally the Distance is setted 0.000; What do you think could be a fair number? I know it dipends on the mesh, but only an advice please. Thank you for the answer

That distance is in Blender units, so it entirely depends on the scale of your scene. I would start at about 10% of whatever your model's dimensions are, and adjust from there.


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Blender 2.8 Grease Pencil disable x-ray
How can I disable the X-Ray effect of grease pencil (aka Annotations), so that what I write on a face of a mesh cannot be seen when that face is hidden? Is it possible?

I had the exact same issue until I realized I shouldn't use the Annotation tool but a real grease pencil layer.
Add > grease pencil > Blank
You then switch from Object Mode to Draw Mode and switch the Stroke placement from Origin to Surface

Very nice I would not have found it myself... All hidden features, and obsolete things in Blender. I think this way of greasing is useful, while the other way is quite cumbersome, unless you want to have pervasive beacons in your model.. :)


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Rigid Body Sphere Shows In Rendered View But Not In Rendered Image and Animation
I have created a roulette wheel trying to get the physics engine to work with it and I have a rigid body for all and they collide when in the rendered 3D view but rendering the image or animation it does not show up. Ill take some screenshots for a better understanding.

Here is the sold view and it is showing up in the scene.

Now I switch to rendered view and all the textures with the sphere still in the scene and works when the animation is played.

Then rendering the image the sphere disappears and I assume it had to with the physics or something but not totally sure and has screwed up my animation.
Any help is greatly appreciated.

Interesting! Can you post the file? https://blend-exchange.giantcowfilms.com/

Yes here is the file. I've only used blender for about a month so the model is very basic.

I'm having trouble reproducing your error. If I render your setup as is, I get a blank render. So I unchecked sequencer in Post Processing, and the result is an image that includes the sphere. This is probably not what you're looking for though?

I am not totally sure it might be from my project being baked I will try moving the project into a new save file and see if that works and Ill get back you as I think that may be the case.

So I tried turning of sequencer and got the same thing as you said. It was what I was looking for but do you have any idea on why the sphere wouldn't show up? Or atleast be able to explain what turning off sequencer did?

Not 100% sure, but this is my guess. I poked around and saw you have something on your video sequence editor (VSE), and sequencer enables the editor. I'm assuming the image you had on your VSE was your image with no sphere, and that's why it was showing up blank on my end. So what happened when you had sequencer checked is that the image with no sphere on your VSE gets priority.

Alright thanks so much for the help moarorleslie I really appreciate it!


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Transfer weight operator changes vertex groups
I started out with an ordinary rigged human character model, complete with vertex groups and correct weights.
Then I did some geometry modification. I had to reassign the vertex groups and that understandibly wrecked the weights.
So the idea was to transfer the weights from the old mesh to the modified mesh. I put the meshes on top of each other and did everything to the book, selecting the source first, then the destination, entering weight paint and hitting weights transfer.
At first it looked great, with all the correct weights in place on the destination mesh.
Then came the shock. I noticed that all vertex groups in the destination mesh had been altered such that every single vertex group whether affected by the weight change or not now comprised all vertices of the entire mesh. Of course that renders the mesh unusable.
I tried all different options in the weights transfer operator, to no avail.
Parenting the source mesh to the destination armature didn't help either.
What could be the problem. I am at my wits end.

So all vertices are in all vertex groups, but is their weight appropriate (eg 0 where there should be none) or is the weight value wrong as well?

You can use the weight tool Clean to fix that. It will remove from the group, every vertex with a weight under the specified threshold.
To remove every vertex with weight 0, from each vertex group :

Subset : All Groups
Limit : 0

that solved the problem, thanks again ...


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hair dynamics doesn't work
I set up a simple hair dynamics system in Blender 2.8 to replicate the problem I have in my original model. No matter what settings I use the top part of the hair is always stuck in place and stretches to the mesh.

Here is a link to the file:
hair dynamics test blender 2.8
There must be something fundamentally wrong either in my setup or in Blender.
Any ideas?

Try turning off smooth shading. Select object, Rt click and set to Shade flat. If this works (it worked for me) you have to copy the scalp parent it to the object and turn off show emitter in the particle settings.

It seems like manually dragging the frame marker along the timeline before baking fixes the issue. It forces it to load the correct data to bake, I guess.

A previous Bake seems to be causing the issue.
In Cache, click "Free All Bakes", then relaunch the simulation with the "Play Animation" button.

Did you actually download the file and try it? I did a "Delete All Bakes" in the Cache section of the particle tab and it didn't work either.

Yes I did and it worked yesterday, but today it doesn't. Maybe I did something else and don't remember. You can change a setting (ie, set particle number to 999 instead of 1000) to force the simulation to be recomputed, it works.


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object array normals changing along curve
In order to model a zipper, I duplicated an edge from the cloth and converted it to a bezier curve. Then I attached an array and a curve modifier to a helper plane. Eventually I parented the zipper tooth to the plane. This workflow is recommended for Blender 2.8 in order to avoid object distortion.
It works with one exception: the plane normals and thus the tooth orientation change along the bezier curve. It starts out fine:

but further up along the curve the plane normals incline:

I would expect the plane normals to stay parallel to the bezier curve along the whole distance.
Well, the bezier curve itself changes direction as well, but the plane normals should follow that change and not rotate relative to the curve.
I've been fiddling with this for some time now and can't find an explanation / a solution. Please help.
Link to .blend file

I think all you need to do is Ctrl A > apply the scale of your curve. Always watch out for non-uniform scaling in object-level transforms.

That did it. Question answered. Thank you.


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How to turn off screencast mouse highlighter?
I tried the Screencast function, and now this thing wont go away!! :((

Hit the dismiss button, labelled "Capture",  to the right of the render engine select box.

That was the first thing I did. The highlighter still persists!

Ok so I reverted to an older save file, and now its working normally. Highlighter disappears when I stop capture.

Lol, just built a new version of blender (from git repo)  and it displays  the behaviour you described.


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Particle Hair renders outside lines
I've been struggling with hair for some time and I didn't find any solution to my problem, so I decided to try and find a solution here. I'm having a problem when I add a line of hair to scalp that they render in a strange way(out of place).

I'm not sure if this is the supposed to happen but it looks strange to me, even more hard way to make a hair style since when I add more hair to scalp they start to come out of chin, forehead, cheeks, etc.
I would really appreciate any help or insight.

Apply (Ctrl A) rotation and scale of your mesh, then reduce the radius in which the children are spread around the hair parent.

Thanks for the help, it worked.  I had to set radius to 0.01 or 0.02 to get same results as u. Do u think thats normal since u have it set to 0.200?
Link to printscreen printscreen.
By the way, what does applying to rotation and scale of mesh acctouly do?

The radius value is relative to the mesh dimensions, so it can vary quite a lot. Applying transormations it means that every variation of loc, rot or scale in object mode is transferred to the vertices, as it were maden in edit mode, so the final object results to be located at (0,0,0), has a rotation of (0,0,0) and a scale of (1,1,1). A lot of functions in Blender require to have theese values to work properly, expecially when animating, simulating physics, fluids, using modifiers and so on.


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Trouble with input preference setting using macbook pro
I am having trouble with selection and input functions working on a macbook pro. Is there a macbook pro preference setting or addon for this

I very much doubt it. Being a Macbook shouldn't change anything, all MacOS systems should behave relatively the same except for bugs/unexpected behavior.

because I only have trackpad which left clicks only....

Well, then no. There just aren't enough inputs for what a mouse is supposed to be used for (take it with a grain of salt, I've never even seen a Macbook in the wild before so I could be wrong). You really should look into getting a mouse if you are planning on taking 3D work seriously, it will make your life infinitely easier.


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Displacement not working properly - following Blender Guru rope tutorial
this is my first post so let me know if I'm doing something wrong.
I'm following this Blender Guru tutorial: https://youtu.be/1drRNphACMc?t=955
At the 15:55 mark he changes Displacement to True, which I've done, but my result doesn't look like his. Everything up until this point has, and I can't see any differences between what he's done and what I've done.
Mine looks like this instead:

And when he adds a Subdivision Surface modifier, it gets more bumps which make it look more ropey, but mine just goes back to looking completely smooth, like so:

Any advice on where I might be going wrong here?

before, just after setting displacement to "true" he did a double tab to enter/exit edit mode (16.03), and that made the rope became much more "influenced" by the bump...  only after he added a subsurf and also activated "adaptive"... are you sure you followed strictly his workflow?

I've definitely done all of that to the letter :/ Feeling a bit lost. I must have some other settings incorrect I think, but I don't know what could be causing it?

You might have to set your displacement map to non color data in the node editor.
Here is an example of microdisplacement with the map set to color data:

And this is the same image, set to non color data:


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Changing the mouse pointer to be like the default blender Rotate pointer?
I was looking into bpy.context.window.cursor_set() because I want my modal add-on to have the same cursor that you get when rotating stuff in blender, but it seems that the parameters for curusor_set don't include these kinds of arrows. Nor could I find a setting to change the orientation of the mouse pointer graphic as I rotate something. There is also a dotted line when you use blender's default rotate, that goes from the mouse pointer to the rotation pivot. I'd also like to implement that.
Does anyone know how to achieve something like that? Instead window.cursor_set(), should I be looking more at custom bgl stuff?


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Adding a Bezier Curve with a single point at 3D cursor [beginner]
Complete beginner to scripting. I'm trying to create an add-on that would allow me to add a bezier curve with one single control point (vertex) at the 3d cursor.
This is what I have:
bl_info = {
    "name": "Single Point Curve",
    "category": "Object",
}

import bpy

class HalfBoolMirror(bpy.types.Operator):
    """Single Point Curve"""      # blender will use this as a tooltip for menu items and buttons.
    bl_idname = "single.point.curve"        # unique identifier for buttons and menu items to reference.
    bl_label = "Single Point Curve"         # display name in the interface.
    bl_options = {'REGISTER', 'UNDO'}  # enable undo for the operator.

    def execute(self, context):        # execute() is called by blender when running the operator.

        # The original script

        bpy.ops.curve.primitive_bezier_curve_add(view_align=False, enter_editmode=True, location=bpy.context.scene.cursor_location, layers=(True, True, True, True, True, True, True, True, True, True, True, True, True, True, True, True, True, True, True, True))

        bpy.ops.curve.handle_type_set(type='VECTOR')

        bpy.context.object.data.show_handles = False

        bpy.context.object.data.show_normal_face = False

        bpy.ops.curve.de_select_last()

        bpy.ops.curve.delete(type='VERT')

        bpy.ops.curve.select_all(action='TOGGLE')

        for area in bpy.context.screen.areas:
            if area.type == 'VIEW_3D':
                ctx = bpy.context.copy()
                ctx['area'] = area
                ctx['region'] = area.regions[-1]
                bpy.ops.view3d.snap_selected_to_cursor(ctx, use_offset=False)
                break

        return {'FINISHED'}            # this lets blender know the operator finished successfully.

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

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

    if __name__ == "__main__":
    register()

This gives me an error when trying to enable the addon in User Preferences. The error is
line 18
    bpy.ops.curve.primitive_bezier_curve_add(view_align=False, enter_editmode=True, location=bpy.context.scene.cursor_location, layers=(True, True, True, True, True, True, True, True, True, True, True, True, True, True, True, True, True, True, True, True))                                                                                ^
TabError: inconsistent use of tabs and spaces in indentation
At some point I also got an error saying "incorrect location" or something at line 18. Unable to reproduce it now...
The script works as intended when running it in the script editor such as this:
import bpy

bpy.ops.curve.primitive_bezier_curve_add(view_align=False, enter_editmode=True, location=bpy.context.scene.cursor_location, layers=(True, True, True, True, True, True, True, True, True, True, True, True, True, True, True, True, True, True, True, True))

bpy.ops.curve.handle_type_set(type='VECTOR')
bpy.context.object.data.show_handles = False
bpy.context.object.data.show_normal_face = False
bpy.ops.curve.de_select_last()
bpy.ops.curve.delete(type='VERT')
bpy.ops.curve.select_all(action='TOGGLE')
for area in bpy.context.screen.areas:
    if area.type == 'VIEW_3D':
        ctx = bpy.context.copy()
        ctx['area'] = area
        ctx['region'] = area.regions[-1]
        bpy.ops.view3d.snap_selected_to_cursor(ctx, use_offset=False)
        break

But I can't get it to work as an Addon.

The error is about the whitespace in your script, check that you have each line use the same indentation. It is better to not use operators within your own operator, have a look at this answer for an example of another way to do it.

Trying to run it here I got a bad identation error on line 52 in register().
Fixing that I could install the addon, then it complained about
Traceback (most recent call last):
  File "D:\Duarte\System\Blender\2.78\scripts\modules\addon_utils.py", line 349, in enable
    mod.register()
  File "D:\Duarte\System\Blender\2.78\scripts\addons\SinglePointCurve.py", line 44, in register
    bpy.utils.register_class(HalfBoolMirror)
RuntimeError: Error: Registering operator class: 'HalfBoolMirror', invalid bl_idname 'single.point.curve', must contain 1 '.' character

Apparently your bl_idname = "single.point.curve" on line 10 can only have one one "." period character in its name.
Changing it to bl_idname = "singlepoint.curve" seemd to fix the problem and the script installed fine, though I could not see it anywhere in the UI.
This is my final result
bl_info = {
    "name": "Single Point Curve",
    "category": "Object",
}

import bpy

class HalfBoolMirror(bpy.types.Operator):
    """Single Point Curve"""      # blender will use this as a tooltip for menu items and buttons.
    bl_idname = "singlepoint.curve"        # unique identifier for buttons and menu items to reference.
    bl_label = "Single Point Curve"         # display name in the interface.
    bl_options = {'REGISTER', 'UNDO'}  # enable undo for the operator.

    def execute(self, context):        # execute() is called by blender when running the operator.

        # The original script

        bpy.ops.curve.primitive_bezier_curve_add(view_align=False, enter_editmode=True, location=bpy.context.scene.cursor_location, layers=(True, True, True, True, True, True, True, True, True, True, True, True, True, True, True, True, True, True, True, True))

        bpy.ops.curve.handle_type_set(type='VECTOR')

        bpy.context.object.data.show_handles = False

        bpy.context.object.data.show_normal_face = False

        bpy.ops.curve.de_select_last()

        bpy.ops.curve.delete(type='VERT')

        bpy.ops.curve.select_all(action='TOGGLE')

        for area in bpy.context.screen.areas:
            if area.type == 'VIEW_3D':
                ctx = bpy.context.copy()
                ctx['area'] = area
                ctx['region'] = area.regions[-1]
                bpy.ops.view3d.snap_selected_to_cursor(ctx, use_offset=False)
                break

        return {'FINISHED'}            # this lets blender know the operator finished successfully.

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

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

if __name__ == "__main__":
    register()

If you also remove the extra indentation for the if __name__ and the following line then running it in the script editor will register the operator.


text:
How to remove dead BMVerts from a list?
I am trying to fix a bug in my script that happens in rare instances. I believe the bug occurs due to the very last thing the script is doing, which is:
bmesh.ops.remove_doubles(bm, verts=verts_to_weld, dist=0.001)

I think the problem is that verts_to_weld refers to a list of BMVerts that contains dead elements. This is because earlier in the script I use bmesh.ops.delete() to get rid of inner faces after using bmesh.ops.extrude_face_region(). So essentially my Remove Doubles is referring to some vertices that have been deleted earlier and don't exist in my bmesh anymore, but are still in the list. Is there a way to take the list verts_to_weld and remove any dead verts from that list? Thanks! Here's what my error looks like and also the print(verts_to_weld) at the bottom:

Look at the is_valid property of a bmesh element.
In this case you have verts in your list that are no longer valid. Use BMVert.is_valid to check.
Try
bmesh.ops.remove_doubles(bm,
        verts=[v for v in verts_to_weld if v.is_valid],
        dist=0.001)

From the print output, it looks like the 'dead' vertices don't have any index associated with them. Did you try iterating through the list -  verts_to_weld -  and removing vertices with index == None? Or maybe print the index of all the vertices in the list and see what it is for dead vertices. Most likely it won't be an int.

Very, very  unlikely an int property is no longer an int. See the documentation  BMVert.index  Dead bmesh elements are marked as invalid eg is_dead = not vert.is_valid

@batFinger I tried checking the is_valid flag of the deleted verts. But they had it set to True. That's the reason I thought it could be determined through the index. Maybe I missed something while making the delete call.

The v.is_valid works perfectly for me.

@z01ks Glad to know that :)


text:
How to get list of bm.verts that belong to a deform layer?
I have a previously assigned Vertex Groups on my object. After creating the bmesh, if I understand correctly that Vertex Group should now be dvert_lay = bm.verts.layers.deform.active. If I print that, it looks like this:
<BMLayerItem object at 0x000002A7E18B5A50>

I'd like to get a list of bm.verts from my deform layer that could be used with bmesh.ops. It should have this format:
[<BMVert(0x000002A7818090B0), index=12>, <BMVert(0x000002A7818090E8), index=13>, <BMVert(0x000002A781809120), index=14>]

Any help appreciated.

OK I managed to find the values I needed by printing these variables:
# Layer Deform is the vertex group layer in bmesh mode.
layer_deform = bm.verts.layers.deform.active
if layer_deform is not None:
print('--- This is the deform layer info: ---')
    for vert in bm.verts:
        dvert = vert[layer_deform]
        print('vert index: ', vert.index, 'vert id:', vert,'vertex groups:', dvert.items()) #dvert.items gives you two elements: int of vertex group (I think by the order they were created added), and a 0.0 to 1.0 about the weight. If the vert doesn't belong to any vertex group, this dict will be emtpy. vert gives the BMVert in this format: BMVert(0x0000000012998B88)
print('--- End of deform layer info ---')

Related https://blender.stackexchange.com/questions/69426/accessing-weights-of-a-bmesh


text:
Using Local Transform Orientation for Vertex Rotations
I am creating a script to rotate a vertex selection in a very specific way. I have so far figured out how to set the pivot point to ACTIVE ELEMENT, following a hint from this thread on context overrides:
However, the transform.rotate command doesn't take into account whether the constraint_orientation is GLOBAL or LOCAL or any other. My Edit Mode vertex selection always rotates around Global axis.
I have also looked into transforming with object.matrix_world and mathutils.Matrix.Rotation but I'm not sure if this is going to work for vertex selections? It seems to be working only for Object, not Mesh Data?
Could anyone help me figure out how I can use Local or Custom Transformation as the constraint_orientation when rotating a Vertex Selection in Edit Mode, or whether there's another path to this. Thanks!

For Local Transform I managed to get rotation to work by using transform.rotate where the axis parameter is axis=Vector(self.my_axis)*bpy.context.object.matrix_world.inverted(). However I am still looking for a way to get the Custom Transforms to work for rotations in Edit Mode.

If you are using operators, look at the constraint_orientation parameter to bpy.ops.transform.rotate. For bmesh.ops.rotate I think space is the matrix you want to set.


text:
Best way to rotate a vertex selection using a Modal?
I'm trying to figure out how I should set up a modal operator that would rotate a vertex selection in Edit Mode, based on the MOUSEMOVE value, very similar to the default rotation in blender. I'd modify the script further later, to achieve some particular functionality.
The problem is, that if I enter bpy.ops.transform.rotate() or bmesh.ops.rotate() inside the def modal() function, what I get is that with every MOUSEMOVE event (every pixel that the cursor moves on screen), the rotation is triggered and thus every time the user moves the mouse by one pixel, the selection is rotated by a given value. What I'd like is that the mousemove simply update the rotation value. In other words, I'd like there to be a rotation happening that gets its value from the modal mousemove distance. What I have right now is the rotation command simply running with every mousemove and adding a certain amount of rotation to the selection. Hope that makes sense.
I've tried many things unsuccessfully, but I don't want to make this post unnecessarily long by describing all my attempts. I'd really appreciate some suggestions on the best way to achieve a Modal rotation operator pretty much exactly like the rotation works in Edit Mode...

Related , Emulates object mode rotation using the view vector as rotation axis. .. be easy-ish to update with bmesh.ops.transfrom(...) to rotate selected verts.


text:
Blender python, how to import external modules to an addon, "Blender3D python win10toast"
I'm trying to import external modules in an addon, but I can't find a way to do it.

In the addon install a "virtual environment" where I have downloaded some modules like win10toast that is used to use windows messages.

However, I noticed that Blender uses its own "Virtual Environment". I mean Blender has its own python, so I can't import the modules that I have in the virtual environment that is inside the addon, since blender doesn't find those modules because obviously it's not in its virtual environment.

I read that it is possible to use the "sys" module to tell the compiler where a module is located, however I can't get it to work.

import bpy
import sys

sys.path.append("C:\Users\Ariel\Desktop\Test_message_VScode\venv\Lib\site-packages\win10toast")

from win10toast import ToastNotifier

for i in sys.path:
    print(i)

n = ToastNotifier()
n.show_toast("GEEKSFORGEEKS", "You got notification", duration = 10)

Someone who can give me an idea of how to import external modules to Blender3D addons?
I leave attached the folder with a virtual environment of python with the module for windows messages working in VScode.
https://drive.google.com/file/d/1OR945s227EBbRfbkAqDVi3f8eVWkT_5r/view?usp=sharing
and the blender file where I try to import that module from the external virtual environment.
https://drive.google.com/file/d/1KjDl0x6usoi16AYWbMCl4QkETNfVxwo7/view?usp=sharing
Thank you so much.


text:
bake IK bone position
All I want to do is pose an IK chain with its controller bone. Then I want to store the position of the bones in the chain as a key frame, so they stay there when I turn off the IK constraint. I played with the bake action function, but to no avail. There must be a simple way to do this.

You have to bake the action checking "Visual Keying" and "Overwrite current action" and have bake data set to "Pose" in order to work.
Then you can decide wheter or not bake only selected bones, clean curves leaving off unnecessary keyframes, clear constraints or leave them on.
If this doesn't solve, please upload your armature.

I hadn't considered "Visual Keying". That did the trick. Thanks.


text:
Why is my PNG texture messed up after I import it?

I made a leaf texture in photoshop and exported it as png and I hope to use it in a tree model I'm making in blender. However after I import it using the add-on "Import Images as Planes", this is the result. Does anyone know why this is happening?

Found out the reason was because when selecting the image there is an import options box on the bottom-left corner of the window which contains an option labeled "Use Alpha" which must be checked in order for the image to be imported properly.

Try Blender 2.79. I see no problem here. But be sure to make the background of the leaf transparent in Photoshop. No white layer beneath.


text:
Gltf mesh compression on Linux
I'm on Arch Linux and Blender 2.91. I want to export a scene in .glb (gltf 2.0) format with mesh compression. According to blender manual, that should be supported via khr_draco_mesh_compression extension. A friend of mine who's using Blender 2.91 on Mac has the compress option under geometry section of the exporter settings but I cannot see such option on Linux.
Any ideas?

The official build has this option. Please download the official release from the website and check if the option is still missing. If it is missing, file a bug report on Blender's bug tracker, if it isn't file a bug on Arch's bug tracker as the package maintainer didn't build it properly.

Ok, just wanted to make sure I did not miss something in my setup.

Ok I think it's an issue with Arch Linux package as downloading and executing 2.91 from Blender site shows the compress option


text:
Manipulate Vertex Indices
Good Day!
Situation:
I have multiple objects with the same amount of vertices and a similar though deformed topology (all objects originate from the same one). I need to do two things to all my objects: Use them as shape key for each other and copy their weights by topology.
Unfortunately, the vertex indices differ, thus the result of both actions is messed up.
Question:
Is there a way to manipulate the vertex indices so they match in all objects?
Failed Attempts:
I tried an addon called "copy vert IDs". The IDs did undergo some changes but weren't matching.
I also used the Data Transfer modifier, copied vertex Data but it didn't seem to have any effect on the indices.
Thank you!

How different are the meshes? What kind of deformations are we talking about?

Not very different - they are faces. The deformations are meant for things like old/young or thin/big. If I could use them as Shapekeys (which was originally not intended) I could change things like the age smoothly. Nevertheless, the deformations are strong enough to ruin functions like "nearest vertex".

The solution I had rely upon vertices normals and locations, so I am afraid with such drastic changes, there is no easy way to do it.
If the models are not high poly, you can duplicate the model, align its vertices (using snapping) with the reference model, then compute a loop up table using KD Trees, apply it on the original model. If this is an option, I can write an answer with more details.

Thank you! I will give the snapping method a try. I think I know, how this could work.

Okay, this would probably work, but it is not very efficient. You have to snap vertex by vertex since proportional editing ignores the snapping. With about 5k vertices, it is a very slow method. :-/

You don't have to snap them, we just want a rough alignment, nothing exact. So proportinal editing or sulupting would suffice for most of organic models. I am writing an answer now, lets hope it works for you.

This is an old question, so I don't know if it's worth the effort to add my solution. If anyone is interested let me know and will try to explain my solution. It is using Geometry Nodes (incl. Repeat Zone, so it only works from 4.x). It needs the two meshes and the edge indices of the same edge in both meshes + the indices of the same end vertex of that edge in both meshes (i.e. 4 indices in total). The meshes can be completely distorted, as long as the topology is the same, it creates a perfect mapping between both. Speed is also not too bad: 600ms for a mesh with 13k vertices.

Lets say you have a reference object (Red) and a deformed object (Blue), while both have the same mesh structure, the vertices indices are different, we want to align the vertices indices so that we can create proper shape keys and smooth morphs.
The solution rely on computing a look up table for vertices based on their closest vertex in the reference object using a KD Tree. In order for this to work, an instance with the same indices structure of the deformed object has to roughly align with the reference object, if the deformation is too extreme, you will have to try to align the deformed object manually someway. This can be done by snapping the vertices manually, roughly aligning them using sculpting or proportional editing, for instance, I am going to duplicate the deformed object and try to align it using proportional editing:

It doesn't have to be precise, it just have to good enough for the algorithm to work.
Then we are going to send that to Animation Nodes where we sample both the vertices locations of the reference object and the duplicated object we just edited. Then I am going to create a KD Tree from the reference object's vertices locations and use the Find Nearest Point Node to find the indices of the nearest vertices in the reference object. If we view the indices of the vertices of both objects and cross reference them with the output indices in the node tree, we will find that they indeed match:

Notice that the output list tells us that the vertex at index zero should be at index 32, the vertex at index 1 should be at index 15, the vertex and index 2 should be at index 22, and so on. If we now get the vertices from the deformed mesh at the output indices, we will get the vertices in the same order as the reference object but in the locations of the deformed object:

The edges and polygon indices of the new mesh are that of the reference mesh. All you have to do now is output the mesh and use it to create your shapekeys.

How did you do that this fast? :-o Thank you!

Alternative Solution:
It is possible to use the "Copy Vert IDs"-Addon even with deformed meshes.
Therefore you have to select 2 adjacent faces on the origin mesh and hit ctrl+c -> "copy vert IDs topological". Next, select the same 2 faces on the target mesh and hit ctrl+c -> "paste vert IDs topological".
All indices should match now.
This solution may not work for everyone though: I have downloaded the Addon on a forum currently not available, and I have found no documentation.
(Stil not 100% happy with the solution, I did more research on the topic and finally decided to write my own python script by merging "Magic UV" by Nutti and "Copy Vert IDs" by Jose Conseco, since I know "Magic UV" was capable of the two-adjacent-faces-topology-identification-method and "Copy Vert IDs" to reassign Vertex indices. To my surprise, I found this method already built into the "Copy Vert IDs" script and learned that it is in fact based on "Magic UV".)


text:
No rig object when exporting character from blender to unity
I am trying to export my character from blender to unity, everything is being exported correctly except for the rig. I can't find the rig and also the body parts of the character have no root bone. Which is usually to be found in the rig object. When I select the FBX file I can access the rig tag.

After much searching I found out that in unity when you select the FBX file and go to the rig tab I had ticked the option "Optimize Game Objects" which caused the rig to disappear. After unticking the rig was back in the FBX and in my game object.


text:
Diamond Shape Rounded
Even tho I am new to Blender, I have tried many techniques posted on stack. However, I can't find a way to make this shape with a solid element (with faces).

That's not possible to create with 1 face if you mean that. Subdivided plane is needed which will provide geomtetry available for bending

Final:

Steps:

Subdivide a Plane (W > Subdivide) as much as you need, keep in mind to have vertex in the center of a Plane. So you will need odd number.
Select vertex in the center.
Turn on Proportional Editing (you can switch trough different falloffs to get different results).
Scale down (S) and increase Proportional Editing influence size - MouseWheel.

thk really nice


text:
Select Multiple Key Frames in Timeline Editor
How I can select multiple key frames in the timeline editor so that I can delete them all at once .

The timeline isn't actually an editor. It's simply a viewing port for all the keyframes in your animation. What you can do is:

Go to the Graph editor and select the objects that are keyframed
Move the playhead in the timeline to the keyframe you wish to delete
Hover your cursor over the graph editor and press Ctrl-K
Go to the next keyframe and repeat steps 2-3
Press X to delete the selected keyframes

PLEASE NOTE This process works if you want to delete all keyframed information about the selected objects. If, say, you just want to delete X-Location info but not Y-Location info, you have to manually select each keyframe in the Graph Editor.
Hope this helps!


text:
Extra Face when cutting a window
I'm kind of new to Blender and I ran into a problem.  I am creating modular segments for a house.  For some reason when I created the segment with a window in it, blender split the front face into 2 faces when I go into edit mode.  Is there a way to rectify this?  I created the segment using 2 cubes.  One cube is the size of the wall, the other i used to cut out the window using a boolean modifier. I tried the "f" key and that didn't work for me.

Don't use booleans learn proper modelling techniques

A face by definition can not have a hole inside it.  if you need the hole, there has to be 2 faces.  Trying to merge the 2 faces into 1 will not yield you any viable result.  Instead, I recommend you to get your own lines cut into the faces so the cuts are nicer to look at, and easier to be left alone.

You way want to check out the archimesh addon for modular house parts.

One way is to subdivide a plane, select, with B, the faces you want to remove or the window and delete them. Then you select the object and extrude it.


text:
Blender 2.79 Principled BSDF Shader + Substance Painter
I want to have shiny paint on top of the metal material. I made a material in Substance Painter. If I use shaders from Andrew Price, I am able to achieve this effect. However if I try this with Principled shader, that shininess of the paint is gone. Maybe I'm doing something wrong?
Advice would be much appreciated, thank you.
[![enter image description here][1]][1]

Found a problem. Hopefully my mistakes can be useful to someone.
When you are in substance painter. Make sure to turn off properties of the material which a material doesn't have. In my case "Paint" doesn't have metallic property.


text:
"Apply Scalings" parameter missing in export_scene.fbx?
I'm trying to write a simple exporter script to do an FBX export with all the settings I want already selected, for convenience. Reviewing the API on export_scene.fbx, I don't see a parameter matching the "Transform -> Apply Scalings" option in the regular export UI (as in the image below). Is this something that's absent from the documentation, or is there no way currently to assign this from script? Thanks!

I'm not sure because I'm pretty new to blender scripting but it appears to me that dropdown in question is not selecting parameters for the fbx export function, it's just applying a transformation to the objects that it's exporting using the regular mechanism for applying a transformation. That is: it's scaling by a factor, applying the transformation, running the fbx export, then scaling by the inverse factor to undo the first scaling, then applying the transformation again. So in my script, I'm basically doing the same thing.
What I'm doing that seems to be working for me is scaling by some constant factor (100 in my case):
obj.scale = (100, 100, 100)

Then applying the scaling:
bpy.ops.object.transform_apply(location=False, rotation=False, scale=True, properties=False)

Then exporting with the global_scale set to the inverse of my scaling factor:
bpy.ops.export_scene.fbx(
    filepath=fname + ".fbx",
    use_selection=True,
    axis_forward='-Z',
    axis_up='Y',
    global_scale=0.01,
    apply_unit_scale=True)

and finally setting and applying the opposite scaling factor after running the export:
obj.scale = (0.01, 0.01, 0.01)
bpy.ops.object.transform_apply(location=False, rotation=False, scale=True, properties=False)

this may be a very whacky and roundabout way of doing it, but it seems to be working for me and sets my object back to how it was before I ran my script.


text:
None Type Texture in Image Breaking Export (Somehow)
So I'm learning Blender 2.78 and am... definitely still a total newbie at this point, honestly, the depth of functionality in this program is HUGE. My problem, however, is fairly specific, and is proving rather intractable, so I figured I'd give it a shot here.
Long story short: I am working on a custom model that I'm planning to export from Blender to XNALara, and the export script I'm using keeps breaking on one specific model with the error "AttributeError: 'NoneType' object has no attribute 'filepath'", which I understand to be the Python equivalent of attempting to read a property off a null value. So I track back through the source code and find this line:
texFilePath = textureSlot.texture.image.filepath
So, it would seem I somehow have a textureSlot which has an entry and a texture value, but not an image.
The problem is... all of my texture slots for this object have images??

I've googled around for similar issues before and saw a different export script where someone had run into this sort of issue due to a glitched texture slot. I have combined and split this mesh with a few other objects at various points, and while I thought I had fixed the textures after doing so (every single texture on that list definitely belongs with the model), something is clearly broken. Unfortunately, I just don't know enough about what's going on here to fix it. I've tried adding and clearing the texture slots, to no avail. I can't even figure out which texture slot is broken because I don't know enough about Blender 2.78. I'd really rather fix the model than try to update an unfamiliar script in order to try to skip broken texture slots.
Has anyone run into a problem like this before? Am I correct in my thinking that there's probably a broken texture slot? And if so, how do I determine which texture slot is broken here, and how do I fix it? I'm willing to upload a minimal .blend file with only the helmet if that will help.

I figured it out. As I mentioned above, I'd joined and split the mesh a few times in order to better fit other mesh parts to the helmet, and when doing that, I'd left old materials attached to the object. I went into the material editor, removed all materials that did not appropriately belong to the object, re-exported, and it worked fine.


text:
Blender detects 2 gpu's but only renders on 1
i have 2 Gtx 1080 Ti's gpu's and both are shown in the User Preferences->System TAB but while rendering it only shows 1 tile.
The issue occured some days ago and before that it worked fine with 2 tiles.

I already reinstalled blender and the graphics driver.
I also found that i can't only check 1 card in the Preferences->System TAB, it selects or deselcts only both of them.

I also tried with the latest 2.8 test release, its the same behavor.
I was on Blender version 2.79 when it started to happen and now i am on 2.79b and it is still occuring.
I am on the latest nvidia driver.
I am on win 10.

Both gpu's running in SLI, i don't think that would be a problem as it always worked under sli.

"Both gpu's running in SLI" < That's the issue right there. As far as I know SLI or Crossfire or any other GPU pairing technology make it so multiple GPUs are presented as a single entity to at the operating system level, not even sure how Blender can even see both

yep, the 'L' in SLI stands for Link.  your OS sees those two cards linked-together as one.  Blender should render faster when you disable SLI mode, because it can then multi-thread tiles.  https://www.computerhope.com/issues/ch001167.htm

Strange, disable sli did work but i am 100% sure it worked with sli tuned on before, well thank you anyway

You probably suffered from a windows / nvidia update that changed the sli profile or something like this. Anyway, I would never enable sli for working in blender since the only you can expect (if ever it worked) is having 0.80 of the performance of your two cards together rendering one tile at a time. Windows 10 is often messing around with stuff while updating, it's a variable multiplier by itself and now you remind me why Ubuntu is also on my system.


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Why is this happening to my rig?
I am following a tutorial about rigging a mesh and when looking at the weight painting, I noticed this problem.

https://i.sstatic.net/ev0tX.jpg
Can anyone explain what is happening??
Thank you.

You might have to click the very bottom bone and subtract the weights for that bone. It's possible the very bottom bone is controlling the bottom foot and thus preventing the vertices from moving


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Can someone explain why my models hips are doing this after subsurf modifier?
I am very new to blender and I decided to make a man. However when I apply a subsurf modifier, my mans hips look strange. Can anyone explain why??

Here is a link for my images...
https://i.sstatic.net/7C5HB.jpg
Thanks.

Looks like you have some extra geometry in the hip area. Try using Remove Doubles or fixing it manually.

Just found it. Turns out that the edge was just overlapping a face, instead of creating two. Thanks anyway.