text:
Combination of rotation around fixed point and waves
I am new to Blender (downloaded it this week) and I am currently modeling a very basic wave energy converter. It is supposed to move up and down with the waves and pivot around a rigid connection point. I have manually done this using keyframes to provide an idea of what I am looking for and attached it below. I was wondering if there is a way to do this automatically though so that I can play around with wave size, height, direction, etc. without having to worry about manually adjusting keyframes every couple of frames. When using copy location the object moves up and down on the y-axis (shown below) and I can't figure out to fix the pivot point. Also, when using that method the object doesn't seem to be following the waves very well so if there are any recommendations for that it would be appreciated. Thank you!

The idea is already the right one - you just need to break it down furter.
There are 3 different objects here:

The float, getting pushed up and down by the waves (copy location)
A fixed anchor
A connector, pointing from the anchor towards the float (locked track)

We can sample the position the float will have by creating some empties. These get projected (shrinkwrap modifier, project, align to normal ) on to the waves. A single one will do, but averaging over multiple ones makes everything smoother. While doing so we can also copy their direction to make it "follow" the slope of the waves.
The connecting rod needs to have its origin in the pivot point of the anchor. (move 3d cursor to pivot, origin to cursor)
Given that the float has its origin in the center, it's just a matter of finding the right axis in the "locked track"-modifier.

This isn't a physically correct setup, but it is easy to set up and doesn't require any simulations.

Would this still be possible if the connector is rigidly connected to the floating part? I have edited the original post and attached a picture of the Solidworks model this is based on to help visualize what I mean. Thank you! @IsmirEgal

Sure - if you model it as one solid piece, you only need "locked track"-Constraints on it to point at the empties. (And to make sure the origin is still on the pivot point on the right)

After doing that the locked track command is taking the wrong path. It essentially has the top of the float following the empty instead of the bottom. Therefore, the float is submerged. I have edited the original post with a picture to illustrate. I am sure at this point it is an easy fix but as of yet, I have been unable to figure it out. Thank you! @IsmirEgal

You can rotate the model in edit mode around the y (or x) axis untill the part sits at the right height. The center of this rotation has to be in the origin (where our joint would be), so you need to set the "transform pivot point" - which can be found in the center of the header - to "3d cursor"


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how to paint texture when uv face is scaled down to point

So I have this ico sphere that every face is scaled down to point in uv.
And the uv this perfectly align to every pixel for a 512x512 texture.
But seems I can't paint texture correctly?

Blender file :

Hello, maybe you have overlapping faces in the UV Editor, also maybe inverted normals? Please share your file: https://blend-exchange.com/

Hi , I uploaded the blender file.

I'm not sure why it doesn't work but if you unwrap again with the Smart UV Project for example it will work fine

You can then just paint the image in the Image Editor without worrying about landmarks in the 3d view if that is what you wanted. Forcing the UV to such a tiny place and then using view projection is probably incurring a graphics issue - the 3d view us4es ray casting for the painting, and this might be very difficult. Did you also try the same thing with a plane? Should be easier to contrast the same idea of one pixel per face.

source: Stack Exchange

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

sort: votes


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Problem using the "mask slice to new object" tool
I'm using Blender 3.1.2. I'm trying to separate the hands from the rest of the body:

But when I press "mask slice to new object", this happens:

Does anyone know why this is happening or how to fix this? Thank you :)
edit: I tried masking just one hand instead of both, the same thing happens

Ran into this exact issue when attempting to complete the Thor course from Udemy!

Apply the scale of your object in Object mode (CtrlA)

Thank you! My first time learning of the apply feature :)

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


text:
I exceeded the default Undo limit, then went to Edit>Preferences and changed the limit. But I still can't use Ctrl+Z again. Help?

So, I wanted to create a body of hair for my character without having to do the usual process of adding another Ico Sphere (I'm trying to treat this sculpture as a traditional clay sculpture). I figured I should just use a mask to fill in the hairline. It wasn't a great plan, as I had to repeatedly Remesh the project. So, I tried to Ctrl+Z it all, and when I exceeded the Undo limit, I went to File>Revert to last save. The image I've attached is the Revert version, still not back to the original bald :') I belatedly increased the Undo limit and tried to CTRL+Z again, but it still wouldn't undo anymore. Did I doom myself by reverting? I don't know how to get rid of this. Is there a way to access all of my saves, rather than just my last session or most recent save?
Thanks for you time and consideration!
Edit- I'm told there is no way to fix this. Thanks for your guys' comments, I just wanted to know if I should fix this issue manually (which would take me a while) or if there was some other way. I've started doing the former!

Imagine this - you're walking, and every step you put down a rock. Each rock will stay there until you take 30 steps beyond it, at which point someone else will pick it up (Imagining a 30 step undo limit). Until you have taken 30 steps past any given rock, you can still go back and look at it, but after 30 steps, it's been picked up and is gone forever. Now, say, during your journey, you tell the person that's picking up the rocks to wait 60 steps instead - you can only still go back and examine the last 30 of the rocks at this point because the (second) set of 30 has already been picked up.

Imagine you're in the middle of a chess game and you've told your friend to only remember the last 5 moves you made. Then, suddenly, you turn to your friend and say, "Hey, buddy, can you remember the last 10 moves instead?" Your friend agrees, and you're thrilled and ask him "What were the last 10 moves I made?". He looks at you confused :D

Thanks for your guys' comments, I just wanted to know if I should fix this issue manually (which would take me a while) or if there was some other way. I've started doing the former!

The undo limit on Blender controls how many actions the software will store before deleting the oldest actions to make room for the newest, so increasing the undo limit retroactively unfortunately will not bring back older actions that have already been cleared from memory.


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What is the difference between a meta-object and a mesh
I have been using Blender for a year now, and I have wondered many times,"What is the difference between a meta-object and a mesh?" What exactly is the difference? Why can a mesh not be calculated like a meta-object?
How does Blender calculate the material shaders for the metas?

According to the Blender Manual:

Meta objects are nothing more than mathematical formula that perform logical operations on one another (AND, OR), and that can be added and subtracted from each other. This method is also called Constructive Solid Geometry (CSG). Because of its mathematical nature, CSG uses little memory, but requires lots of processing power to compute.

In contrast, a mesh object is defined by Wikipedia as follows:

A polygon mesh is a collection of vertices, edges and faces that defines the shape of a polyhedral object in 3D computer graphics and solid modeling. The faces usually consist of triangles (triangle mesh), quadrilaterals (quads), or other simple convex polygons (n-gons), since this simplifies rendering, but may also be more generally composed of concave polygons, or even polygons with holes

Also helpful to see the Wikipedia page on Metaballs to further compare the differences between the two, and see the history of the object outside of Blender.
To directly answer your question, a mesh cannot be calculated in the same way as a meta-object, because a mesh object is described as a collection of vertices, edges and faces defining the shape of the object, while a meta-object is only a mathematical formula doing the same.

That makes sense. Thank you!


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How to make glass clear at overlapping point
Is there a way that I can make the overlapping points of these three glass objects clear, or would there be a way that I can control the colors of the overlapping points? I don't want to change the glass shaders of the objects, though, I want to be able to control the color of the glass in that area. This would be extremely helpful.

The whole point is about using glass for this. I want to be able to make the glass a certain color where it overlaps with the other colors.

Are the 3 objects intersecting each other, or just in front of each other? If they're intersecting, you could use booleans to separate them into different objects and change the colors of those. If they're not, you could accomplish this with a pretty complicated node setup involving ray depth, which i'm not fully qualified to explain.

I would need that node setup.


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Applying decal to sphere
I am trying to add a decal to a sphere. This question has been asked before, but the answers aren't really helpful.  Is there a way that I can apply an Image plane to a sphere using the shrink-wrap modifier, and be able to still animate it on the sphere? I have already tried subdividing the image, and using the shrinkwrap mod., but the result is a distorted image.

Can you be more specific about how you intend to animate the decal on the sphere?  Have you tried already and failed, is there a problem you have encountered?

Yes. I tried subdividing the plane, and applying the Shrinkwrap modifier, but the decal becomes distorted when I do so.

It would be helpful to add that information into your question, and also link to the other questions that you found unhelpful so that others reading the question have the same info.

No, sadly. What I am trying to animate is the image texture on the surface of the sphere.

Can you draw a sketch of desire result? And what kind of animation you mean? Or can you share some googled referenc that looks similar to your idea, t I can't get the image of what is your goal. BTW any plane image will be distorted in some way on sphere shape.

Thank you for your help and time. I actually found the answer to my question on my own. The way to animate the image on the sphere. (Going around the sphere as I intended) is to add a multi-res to the sphere, and to apply the shrink-wrap mod to the plane. Then I set the plane's origin to the center of the sphere so that the image can be moved around the sphere. It will look like it is on the sphere though, and thus solves my problem.

How to avoid the image from casting shadows on the sphere, if you take a closer look at the edge you will find the shadow


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Create a working microscope in Blender?
I am modeling a microscope, and am wondering if it is actually possible to make the microscope would so that it functions like a light-refractory microscope in real life. (Not an electron scanning microscope).
I.e. it has glass material lenses to refract light and magnify objects .1mm in real world size. Is this possible in Blender, and if so, how could I do this?
What I essentially want is to actually use a series of lenses to magnify an object in .1mm real world size instead of using a separate render.
In one sense, I am asking if it is possible to create an object in Blender at .1mm (microscopic level) real world size, and be able to use a working modeled microscope to be able to see it through a camera's lens.
I'm not looking to be practical about viewing a microscopic object, so that's why I don't want to just make a separate render of it, so I want it to be physically light based.

Related https://blender.stackexchange.com/questions/38139/how-do-i-create-a-magnified-glass-effect-in-cycles

Also related: https://blender.stackexchange.com/a/9093/76173

Or https://blender.stackexchange.com/questions/56812/can-i-model-a-double-convex-lens

Or: https://blender.stackexchange.com/questions/79749/zoom-window-magnification

It doesn't make much sense to do that though. Rendering another scene for the time you are viewing things through the microscope will be a lot more practical.

I want to be able to magnify a minuscule object with a series of "microscope" lenses.

Pretty much answered by comments. Model a number of lenses, align them as if in microscope place a camera (for eye) check rendered result   As commented may need to use Luxrender.  Looking forward to the result you come up with.

I do use luxcore render. Could I make an object .1mm or smaller and be able to view it with the lenses without changing the world size? It would be extremely helpful if you could post an answer with a picture of this working. I haven't been able to do so yet.

Just for fun, you can also get good results with Cycles.
Glass shader with IOR = 1,6 (same as Crown glass used in microscopes)
And a rather simple microscope setup.
Original image with a tiny Suzanne

Magnified using a microscope

Diagram of used setup

Notes:
Cycles, 100 samples + Intel Denoiser
I'm sure better results can be achieved by playing with the lens setup.
Bottom line, it works :).

Could you post the blend file for this setup? Your answer doesn't really explain why you chose this configuration or what the lens sizes are.

Hi :). Sure, I edited the post. But bear in mind, this was just an artistic exercise. I know nothing about microscopes, so I just used a random microscope diagram and played with the setup until it looked 'good'.

The comments already give you all the hints, you can use the default settings.

Add two lenses in between the camera and the objects.
Assign a glass material to the lenses.

With the lenses enabled, the object are appear magnified. To remove the distorsion, we would have to research about lenses. To remove the bloom (sorry), I would have to know the basics of LuxCore.


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How to create a "hollow" glass tube
I am working on a cathode ray tube (CRT) based off of an original model. Is there a way to make a glass object (the tube) hollow? In reality, the tube is not filled with glass, so the glass shader default does not yield a good result. I have tried extruding the faces of the mesh a tiny bit inwards, but the result is that the mesh is distorted on the inside. I also tried duplicating the mesh, and scaling it down a tiny bit, but then I have to set the IOR of the shader to something really low, like 1.05. Is there a node setup, or just some kind of way to model your object so that you can render it like a thin glass tube? I would need to see the inner glass, though, like on here.

My render.

Solidify modifier??  Also CRT tubes were quite thick on the front and acted quite like a lens.

Yep That sort of worked, but not very well. I'll just use that then. I'm making the first model. Not the ones in TVs

What do you mean "sort of worked, but not very well"? Solidify is the exact solution for this problem, how much better can it get?

I was hoping that I would be able to see some of the inner glass, but this works well enough. Thank you!

Can you describe, why your are not seeing the "inner" of the glass and how would see it in real life photography? Images demonstrating the difference would help.

There. I added a couple reference photos.

Perhaps something like this is closer to what you're looking for?

I think this is pretty close to what you've used, but feel free to check out what I've done here.
Transmission = 1
IOR = 1.05
Roughness = 0.167

Thank you this helps. Also is there a way to make only the inside reflective? This would be very helpful.

Actually, adding a little bit of metallic shading fixes pretty much all of my shading problem. Thanks!

No problem and happy holidays!

Use Cycles render with the Principled BSDF Shader with the following settings:
Roughness: 0
Transmission: 1
This will yield results show in attached.

This just gives me the same look as the glass shader.

Ahh, it looks nothing like the render you submitted.  Considering you 'fixed it' by adding metallic shading, I'm guessing you wanted to see both the inner and outer surfaces.  If I remember correctly, the glass for CRTs did have a very thin metallic film/powder on them.


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Nontransparent patches rendered transparent in Cycles?
Original .blend file: https://www.dropbox.com/s/dlipv36yu28rk46/SE.blend?dl=0 (~120MB)

I manually segment out human body parts from an image and make each body part a .png image where the alpha channel is 1 for that body part and 0 anywhere else. So for example, I have a RGBA "leg image" as follows.

Now I use them as textures of planes that are stacked up at different heights in Blender, like this.

Here are the material node settings.

I then render them with Cycles under "full global illumination." Here is what I get.

Sorry for the typo -- should be right arm/leg
As you can see some body parts (e.g., right arm) look transparent, and some even completely disappear. Why does this happen, and how can I fix it?

Your planes are touching, Cycles can't figure out which is in front of what.
You have overlapping planes with or coinciding geometry in your scene.
Organize your blend file, be thorough move them apart in Z direction a consistent amount of units.

Hmmm, by touching do you mean within a certain small range that Cycles cannot distinguish? Maybe here I've produced a bad toy example whereby two planes' z values are exactly the same, but in my real application, there definitely won't be exact touching, and I still have this problem.

In the file I downloaded they are touching, exactly coincident, there needs to be a gap between them, the larger the better.

OK, so I went amiss making this illustration. This is a great point though -- now I suspect there are exact touchings too in my real application. Let me check and get back to you. :-) By the way, BI can handle this touching correctly? I had the same geometry, and the problem showed up when I swtiched to Cylces

No engine, Internal, Cycles, or any other non-blender related can handle overlapping geometry correctly, as far as I know. Sometimes it causes more issues, other less, but it is always considered a bad practice having coinciding geometry regardless.

Note that if you use an orthographic camera, the planes don't need to be close to each other.

Actually you are right! Even in my real model, I do have planes at exactly the same z. I just tried with Blender Internal, not saying that it handles coinciding, but it doesn't expose this as a problem -- everything is visible in Blender Internal, somehow.

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


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Cycles always renders RGB channels to the same values under sun lamp?
I'm rendering a ground surface that "catches" the diffuse reflections from a blue sphere (earth). While I was using a point light, the rendered image is indeed blueish. When I switched to sun lamp, everything looks grayscale.
I've ensured the render output to be RGB, but my rendered image has always the same RGB channels as if it were grayscale.

Could you post some screenshots of the results, scene viewport, lamp properties, scene and render settings, etc?

I figured out why. The reason is that my lamp size is too big, which leads to almost no shadow on the shadow catcher.
So my region of interest is actually illuminated by the white light source (instead of being illuminated by the diffuse reflections). With a grayscale diffuse map, the whole thing renders to grayscale.

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


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How exactly should I set surface normals for a sculpture?
I am building, with Python scripting, a sculpture by creating many plane meshes and joining them together. I have full control of the planes' surface normals, but I'm confused how to set them. As of now, I'm setting them arbitrarily, and the render seems fine.
My intuitions about surface normals are that neighboring faces should have smoothly varying surface normals so that there's no shading discontinuity. Also, when a surface's normal points away from the camera, it appears dark. Are my intuitions correct?
In my case, it's a 3D sculpture that's supposed to be ready for view from all angles, so I can't really set the surface normals w.r.t. a fixed camera. Can I then just set them arbitrarily?
Also, what is an easy of  ensuring "neighboring surface normals are smooth" with Python? Maybe some post processing that smoothes over the mesh?

Here is my model.

Can you post a picture of your model?

@ScottMilner Even better: model uploaded. :-D

I don't get the point. Blender calculates the normal automatically once geometry (vertices, polygons) are associated to a mesh. If you want to calculate normals another way, this may be for some special reasons/effects... which ones? Or is there something I've not understood in your question?

@lemon I am creating many polygons using Python and then joining all of them into one single mesh. Depending on the order in which I create vertices for each polygon, the final mesh, formed by joining the individual polygons, may not have "correct/proper normals" across the surface. I am trying to understand how I can construct the polygons properly such that when they are joined into a mesh, the mesh has "correct normals" across the surface.

In Edit Mode, you can display normals, to see exactly which dir they are facing (N > Mesh Display).

You might be able to simply call normals_make_consistent() operator:
bpy.ops.object.mode_set(mode='EDIT')
bpy.ops.mesh.select_all()
bpy.ops.mesh.normals_make_consistent()

Some models don't always import with consistent normals, because they weren't consistent with the order of their vertex arrangement (clockwise sometimes, counter-clockwise elsewhere, within the same model)

+1. Thanks! I actually did bpy.ops.mesh.normals_make_consistent() already, but I don't really trust this automatic operation, because in this case, even humans may not be able to define what is "consistent" and what is not. So I wish to understand how I should set them.

If I interpret your geometry correctly, then there is no right normal. It should be seen from both sides, because it represents a thin layer of fabric. Maybe you want the faces to be double sided? There's a couple of ways to do it, depending on where and how you render it.
Cycles does render them double sided by default.
For any other renderer you could dupliacte them and flip normals, so that you have one face for each normal direction.


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Export UV mapped texture maps to images?
I have a series of texture maps (such as diffuse map, normal map, etc.) correctly set up in the Cycles node tree.
When I export my model to .obj, I notice the accompanying .mtl file doesn't really specify those maps with tags map_Kd, map_Ks, etc. I understand why this is happening -- you just can‘t really "export" Cycles material. That said, UV mapping is saved in .obj as tag vt.
How can I export those UV unwrapped texture maps out as new texture maps that match with the vt coordinates in the .obj?
I know I can bake the texture to an image, and that image indeed matches with the vt coordinates in the .obj. Although this is almost what I want, it's still different -- I don't need to bake the lighting information, etc. All I need is pixel-shifted-around versions of the original diffuse, normal, etc. maps.

The approach I am taking now is to bake Diffuse with only Color Pass turned on, i.e., without Direct or Indirect. What I get looks like "the pixel-shifted-around versions of the original diffuse map", and it definitely matches the UV coordinates in the .obj file because it's baked. Hence, it serves my purposes for now.
That said, I am not sure if this is really the best way or even the correct way of doing this thing.


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Creating an export file for model in blender
I am totally a newbie to Blender and python scripting in Blender.
What I am trying to do is write a script for one of my models in the Crate.blend file in the scene to extract its vertices and face information and printing it to the console
I use the Blender text editor to write a simple script like below and run the script. This runs fine on the console
import bpy
for item in bpy.data.objects:

    if item.name == 'Crate':
        if item.type == 'MESH':
            for face in item.data.polygons:
                verts_in_face = face.vertices[:]
                print("face index ", face.index)
                print("normal ", face.normal)
                for vert in verts_in_face:
                    print("vertex coords ", item.data.vertices[vert].co)

What I want is to execute this script when I type the following line in the console
blender --background crate.blend --python export-model.py -- Crate

How do I go about achieving this? I think I might need to create an exporter script for the same? I found a promising post for creating an exporter script here
I will paste the script just in case
# Required Blender information.
bl_info = {
           "name": "My Exporter",
           "author": "",
           "version": (1, 0),
           "blender": (2, 65, 0),
           "location": "File > Export > Test (.tst)",
           "description": "",
           "warning": "",
           "wiki_url": "",
           "tracker_url": "",
           "category": "Import-Export"
          }

# Import the Blender required namespaces.
import sys, getopt

import bpy
from bpy_extras.io_utils import ExportHelper

# The main exporter class.
class MyExporter(bpy.types.Operator, ExportHelper):
   bl_idname       = "export_scene.my_exporter";
   bl_label        = "My Exporter";
   bl_options      = {'PRESET'};

   filename_ext    = ".tst";

   object_count    = 0;

   def __init__(self):
      pass

   def execute(self, context):
      print("Execute was called.");

      self.parse_command_line_options();

      if (self.filepath == ""):
         print("No sutable filename was provided to save to.");
         return {'FINISHED'};

      # Get all the mesh objects in the scene.
      objList = [object for object in bpy.context.scene.objects if object.type == 'MESH'];

      # Now process all the objects that we found.
      for gameObject in objList:
         self.export_object(gameObject);

      # Parse all the objects in the scene.
      return {'FINISHED'};

   def export_object(self, gameObject):
      if (gameObject.type != "MESH"):
         print("Object was not of type mesh.");
      else:
         self.object_count += 1;

      return;

   def parse_command_line_options(self):
      modelFile = "";
      myArgs = [];
      argsStartPos = 0;

      if (("--" in sys.argv) == False):
         return;

      argsStartPos = sys.argv.index("--");
      argsStartPos += 1;
      myArgs = sys.argv[argsStartPos:];

      try:
         opts, args = getopt.getopt(myArgs, 'hm:', ["help", "model-file="]);
      except getOpt.GetoptError:
         print("Opt Error.");
         return;

      for opt, arg in opts:
         if (opt in ("-h", "--help")):
            print("Run this as the following blender command.");
            print("\tblender <blend file> --background --python <script file> -- -m <output file>");
         elif (opt in ("-m", "--model-file")):
            modelFile = arg;

      if (modelFile != ""):
         self.filepath = modelFile;

# Define a function to create the menu option for exporting.
def create_menu(self, context):
   self.layout.operator(MyExporter.bl_idname,text="test (.tst)");

# Define the Blender required registration functions.
def register():
   """
   Handles the registration of the Blender Addon.
   """
   bpy.utils.register_module(__name__);
   bpy.types.INFO_MT_file_export.append(create_menu);

def unregister():
   """
   Handles the unregistering of this Blender Addon.
   """
   bpy.utils.unregister_module(__name__);
   bpy.types.INFO_MT_file_export.remove(create_menu);

# Handle running the script from Blender's text editor.
if (__name__ == "__main__"):
   print("Registering.");
   register();

   print("Executing.");
   bpy.ops.export_scene.my_exporter();

I run this script inside Blender text editor and it compiles
Now when I try to run it on the command line with the below command
blender model.blend --background --python myexporter.py

it thrown exception on model.blend as "invalid syntax"
I am completely new to Blender and scripting with python so spare me if I am missing something here.
Thanks

After changing my script as suggested in the second post, I get the following error

My blender file name is "model.blend" and it throws the error as invalid syntax. What am I missing?

both scripts run fine, how are executing the command line ? do you have the script file with the blend file in the same directory ?  and for how you implement your exporter change the exporter function body with your code and modify parse func

Yes I have them in the same directory. Does it have to be a specific directory or any directory is fine? I just created a directory under my documents and pasted all the files in there

Does it have to do something with running the right version of Blender and python? I am using Blender v2.72

The console inside blender is a Python console - instead run blender model.blend --back... from your system console/terminal.

@Htlcs you have to add blender path to the 'PATH' system variable to be able to execute the command in any folder or use the method in the answer

lose the semicolons

this would work for  a command line :
blender myfile.blend --background --python myexporter.py -- -m myobject

where :
blender <blender file>  --background  --python <script file> -- -m <object name>

i have removed 'Crate' you can set the name of the object in the command line ^ ,and removed the the file output since you are only printing to the console .
UPDATE:
as sambler noted you should be running this in a terminal, here is the steps "for windows":

copy the script in a new text file then rename it to exporter.py   "be sure to change the extension from .txt to .py"
go to your blender installation folder  "C:\Program Files\Blender Foundation\Blender"
put your .blend file and exporter.py in this folder
hit shift + right click to open a CMD in this folder
type the command  as follows :
blender model.blend --background --python exporter.py -- -m Crate

Note : you don't need to open blender for any of these steps 'nothing is done inside blender'
This is the script :
# Required Blender information.
bl_info = {
           "name": "My Exporter",
           "author": "",
           "version": (1, 0),
           "blender": (2, 65, 0),
           "location": "File > Export > Test (.tst)",
           "description": "",
           "warning": "",
           "wiki_url": "",
           "tracker_url": "",
           "category": "Import-Export"
          }

# Import the Blender required namespaces.
import sys, getopt

import bpy
from bpy_extras.io_utils import ExportHelper

# The main exporter class.
class MyExporter(bpy.types.Operator, ExportHelper):
   bl_idname       = "export_scene.my_exporter";
   bl_label        = "My Exporter";
   bl_options      = {'PRESET'};

   obj_name        = "";

   def __init__(self):
      pass

   def execute(self, context):
      print("Execute was called.");

      self.parse_command_line_options();

      if (self.obj_name == ""):
         print("No suitable object name was provided .");
         return {'FINISHED'};
      print("Executing......");
      # Now start exporting the target object.
      self.export_object(self.obj_name);
      # Parse all the objects in the scene.
      print("Finished");
      return {'FINISHED'};

   def export_object(self, obj_name):
       for item in bpy.data.objects:
           if item.name == obj_name and item.type == 'MESH' :
              for face in item.data.polygons:
                  verts_in_face = face.vertices[:]
                  print("face index ", face.index)
                  print("normal ", face.normal)
                  for vert in verts_in_face:
                  print("vertex coords ", item.data.vertices[vert].co)

   def parse_command_line_options(self):
      obj_name = "";
      myArgs = [];
      argsStartPos = 0;

      if (("--" in sys.argv) == False):
         return;

      argsStartPos = sys.argv.index("--");
      argsStartPos += 1;
      myArgs = sys.argv[argsStartPos:];

      try:
         opts, args = getopt.getopt(myArgs, 'hm:', ["help", "model-file="]);
      except getOpt.GetoptError:
         print("Opt Error.");
         return;

      for opt, arg in opts:
         if (opt in ("-h", "--help")):
            print("Run this as the following blender command.");
            print("\tblender <blend file> --background --python <script file> -- -m <Object name>");
         elif (opt == "-m"):
            obj_name = arg;

      if (obj_name != ""):
         self.obj_name = obj_name;
         print(obj_name);

# Define a function to create the menu option for exporting.
def create_menu(self, context):
   self.layout.operator(MyExporter.bl_idname,text="test (.tst)");

# Define the Blender required registration functions.
def register():
   """
   Handles the registration of the Blender Addon.
   """
   bpy.utils.register_module(__name__);
   bpy.types.INFO_MT_file_export.append(create_menu);

def unregister():
   """
   Handles the unregistering of this Blender Addon.
   """
   bpy.utils.unregister_module(__name__);
   bpy.types.INFO_MT_file_export.remove(create_menu);

# Handle running the script from Blender's text editor.
if (__name__ == "__main__"):
   print("Registering.");
   register();

   print("Executing.");
   bpy.ops.export_scene.my_exporter();

thanks a lot.
I tried what you said. Pasted your script as it is, but I get the error in the image that I have attached in my first post. My blender file name is model.blend so I don't understand what the error means :(

@Htlcs you're welcome, are you using windows ? if so you should add the blender path to system variables so you can work on any folder

Yes I am running it on Windows 8. I would definitely do what you suggested. Thanks a lot mate!

I had a question. What do the register() modules do? Do I write it because I do not have blender path to system variables defined? I understand how the rest of the code works except  the registration part.

@Htlcs the register adds the exporter to blender UI "File->Export->myExporter" and add it to the operators "bpy.ops.export_scene.my_exporter"  so you don't need to run the script each time to use it you either use the menu or from python console type "bpy.ops.export_scene.my_exporter"

The final image shows you entering the command in blender's python console, which only understands python. The command you are typing is a shell command and it needs to be typed into a terminal emulator, sometimes called the CLI or Command Line Interface.
How to start the terminal emulator will depend on what OS you are using, this wikipedia page lists some terminal emulators for different platforms. Most systems will have one of them installed by default.


text:
Python script won't shift face of simple cube
I'm making a simple script that adds a cube and moves it, and then I want to shift some of the faces, in order to change the cube's width height or depth. When I run it, the cube is created and moved, but altering de cube's dimensions gives an error:
convertViewVec: called in an invalid context
I'm using the code that's shown in the Info window when I select a face and drag it along one of the axes. I'm new to Blender and I can't figure out what's missing here..
import bpy

bpy.ops.mesh.primitive_cube_add()
bpy.ops.transform.translate(value=(0, 6.04281, 0), constraint_axis=(False, True, False), constraint_orientation='GLOBAL', mirror=False, proportional='DISABLED', proportional_edit_falloff='SMOOTH', proportional_size=1, release_confirm=True)
bpy.ops.transform.translate(value=(0, 0, -5.22667), constraint_axis=(False, False, True), constraint_orientation='GLOBAL', mirror=False, proportional='DISABLED', proportional_edit_falloff='SMOOTH', proportional_size=1, release_confirm=True)
bpy.ops.transform.translate(value=(0, 2.9328, 0), constraint_axis=(False, True, False), constraint_orientation='GLOBAL', mirror=False, proportional='DISABLED', proportional_edit_falloff='SMOOTH', proportional_size=1, release_confirm=True)
bpy.ops.object.editmode_toggle()
bpy.ops.transform.translate(value=(0, 1.03954, 0), constraint_axis=(False, True, False), constraint_orientation='GLOBAL', mirror=False, proportional='DISABLED', proportional_edit_falloff='SMOOTH', proportional_size=1, release_confirm=True)

Edit - Solved it by creating a custom geometry, as shown here: How to create a mesh programmatically, without bmesh? (Pointed out by @poor)
The following code now creates a flat cube:
import bpy

verts = [
(2.0, 1.0, -1.0),
(2.0, 0.99, -1.0),
(-1.0, 0.99, -1.0),
(-1.0, 1.0, -1.0),
(2.0, 1.0, 1.0),
(2.0, 0.99, 1.0),
(-1.0, 0.99, 1.0),
(-1.0, 1.0, 1.0)]

faces = [
(0, 1, 2, 3),
(4, 7, 6, 5),
(0, 4, 5, 1),
(1, 5, 6, 2),
(2, 6, 7, 3),
(4, 0, 3, 7)]

mesh_data = bpy.data.meshes.new("cube_mesh_data")
mesh_data.from_pydata(verts, [], faces)
mesh_data.update()

obj = bpy.data.objects.new("My_Object", mesh_data)

scene = bpy.context.scene
scene.objects.link(obj)
obj.select = True

I think this answer has the solution you are after.

Welcome dcvsu :) sambler's answer linked in the comment above should solves your issue, if not feel free to comment here. To position your object see this answers: http://blender.stackexchange.com/questions/26852/python-move-object-on-local-axis/26854#26854 Anyway, Enjoy the site!

Hi thanks @poor. The other answer also adds new faces, and that's not what I want to do. In Blender (manually) I select a face and drag it along one of the axes, changing the cube's width height or depth. (Maybe 'extrude' isn't the right word here).

Ahh - You want to shift the faces, right? If yes, edit your question to reopen it. In general there a 3 possibilities: create a custom geometry via python, shifting the selected faces or scale the object. Number 2 could be expensive, because you have to create an algorithm to get the right face. For 1 see this question: http://blender.stackexchange.com/questions/2407/how-to-create-a-mesh-programmatically-without-bmesh.

I edited the question, but it's solved now; creating a custom geometry via python did the job. Thanks a lot @poor!

Voted to reopen it, maybe you want to answer your own question :)


text:
Laying eye shapes on a curved character head surface
Beginner Question-- I'm trying to model eyes like EvilCorp gets on the eyes of some of its more "cartoony" models (examples: this one or this other one). The eye shapes on both of those images aren't built into the head-- they seem like they're just on top of the head, like buttons on clothing-- but sort of wrapped along the underlying head shape.
In both cases, it seems like I should be able to model out head shapes and then have cylinders sort of wrap onto the head shapes, but I can't seem to figure out how to get that to work, how to get cylinders or squares or anything to wrap along a curved surface.  I've tried using a shrinkwrap modifier like was recommended over here but that doesn't seem to work right.
Suggestions?  Am I headed in the right direction looking at shrinkwrap?  Or any suggestions on good tutorials?  Thanks.

1 Select your cylinder.
2 In properties select the chain link icon.
3 Select in [Add Object Constraint] the "Track to" option.
4 Target: choose the sphere. NOTE: The origin of both objects should be in their center for this to work.
5 Try different "To:" and "Up:" combinations until the flat side of the cylinder is aiming at the sphere.
6 To move the cylinder against the sphere use the translation manipulator, it normally says: "Global" next to it, change that to "Normal" and one of the manipulators arrows will align to the sphere to allow you to translate it till they connect.


text:
How do I export a video from Blender?
I edited a video using Blender today and now I cannot export it. The video is fairly short I just need to make some cuts and add a couple of clips together. Do you guys know how I can export the video?

Make sure that the project properties panel has sequencer enabled and set up your render codec to include a video codec with audio. I'm sure that there is a comprehensive explanation here somewhere

assuming you have the video all cut together in the video sequence editor pannel, open a properties panel and go the the render section (first button with a picture of a camera) there will be all your render setting whch you may personalize. For rendering 3D you would want to first export as PNG files and then post render bring the PNG sequence into the Video sequence editor render it into a final video file, but it sounds like you are trying to do a final video render in which case you go to the output section and choose FFMPEG video, Then under encoding > container you generally want to go with either Quicktime (.mov) or mpeg-4 (.mp4) and for the codec use H.264

Yeah, and how do I get the clip? Where is teh "Export" or "Render" button that puts me the mp4. file into my folder for later use?

@MartinMüsli you can hit ctrl+F12 or use the app menu Render > Render Animation


text:
Does Blender work on IntelHD 4000
I just wanted to know if I need a high graphics card by that I mean like GTX 1000 etc. Because if I want to make a high graphics animation then I would need a high graphics card right?

No you don't, Blender can render on CPU. But a compatible GPU is highly recommended in most cases. You can argue that some CPUs are better than some GPUs, but a high end GPU is probably the most reasonable way to go for most people.
Since you are asking this question though, I would recommend to go with what you have for now and play around and learn the software. The GPU questions is about how much time your computer needs to render. After all you probably don't want to wait several days or month to render your animation and on the other hand, you probably don't need more than you have until you know the software quite well.


text:
How can I remove these dots?
When I zoom in and zoom out on my results. I see a lot of dots on my paper towel. How can I remove them?

You have to wait for the preview to render more samples. As you can see in the information printed at the top it's at path tracing sample 1 out of 32.


text:
How to calculate the distance between two selected vertices?
Now I have got a new problem. I want to measure the distance between 2 selected vertices but I do not know how to do that in Blender. Can you help me? Thanks a lot.

Possible duplicate of How do I measure a distance between two points?

You could use MeasureIt addon that you can enable from User Preferences (ctrl+alt+u), Add-ons tab:

Or you could also use an inbuilt ruler that you can find in the Tool Shelf(t panel), Grease Pencil tab that you can snap to vertices holding ctrl while dragging:


text:
Should I learn Maya because it is superior to Blender in animation?
I have been studying Blender for more than 3 years, I am really in love with it, but I want to concentrate more on rigging and animation, but I am struggling and it's very hard in Blender, and people suggest Maya for rigging and animation.
But I don't know nothing about Maya, should I start learning that also, is it possible to learn both?
Also what do you think, how good is Maya compared to Blender in animation?
Please advice me, friends.

"...and it's very hard in Blender" - Give an example of what do you mean by that. Suggest ask a question specifically about your issue and we'll see "how hard" that really is...

It will not be easier in Maya. Maya is even more complex. It has some more mature functionality, but it also has so much stuff that just doesn't work. It crashes a lot in comparison especially if we are talking about rigging. It is old and full of features and sometimes that's great but sometimes that's also a problem, because old features must be maintained because they are integrated in some workflows of large studios, and often that leads to bugs and things not working together with newer features.

It would be interesting to ask the opposite question on Maya forums "Should I learn Blender because it's superior to Maya in animation?" :D

@brockmann by hard i mean, I have been studying and studying but got no results, there are so many tutorials on youtube, but couldn't find someone who starts from beginning to advanced, in modeling we have blenderguru, but in rigging i find no one, so i am stuck.

@MartynasŽiemys do you know of some great tutorials, whether free or paid, or any book.

Nathan Vegdahl's free youtube full course Human Rigging, then DanPro and LevePixelLevel.

@joshsanfelici thanks a lot, the tutorials that you mentioned are amazing

This question might seem opinion based and therefore not suitable for this platform and I think it actually might be the case. However, I think it is possible to answer it based on facts, or maybe I should say the absence of facts that you should learn Maya instead of Blender or that one of them is superior in animation as a whole.
I can say with certainty that there are no rules or laws that would force you to learn any 3d software instead of another. Blender is free so you definitely do not have any restrictions choosing it instead of any other package. It has all the tools to make animations, and there are studios that use it even for animated feature films and they seem to be happy with Blender instead of Maya. Tangent Labs with their Next Gen is a famous great example.
I think the answer to your question is: no, you shouldn't, meaning you can but do not have to. You can choose whatever you wish.


text:
How would you model a pyramid pattern?
I’m trying to model this kettle with a pyramid pattern on the lower side of the kettle. The problem that I am facing is that I have a Subdivision Surface modifier on the object to give it that smooth round look. If I try to model each individual pyramid, the Subsurf smooths out the pyramid.
What is the best way of achieving this look?

You can model the pyramids either scaling extruded individual faces to 0 and then removing doubles(w->r), or you could poke the faces(alt+p) and then select the middle vertices by the amount of adjacent faces or connecting edges(shift+g menu) and use Shrink/Flatten(alt+s) to move them outwards in the direction the surface is facing. You could then grow selection(ctrl++) and bevel(ctrl+b) the edges so they remain sharp(ish) after Subdivision Surface modifier. You could crease the edges(shift+e) instead of beveling to have them completely sharp with the Subsurf, but that would be a bit unrealistic since edges are rarely completely sharp.

Edit mode:
Enable face select

Select a ring of faces by having cursor in between adjacent face

Separate by selection

Poke
Object mode:
Select new object
Edit mode:

Select all

< I > inset
Select individual in tool properties

 Scale
Drag outward

Object mode:

Parent new object to original
Adjust settings / remove subsurf modifier on child object

This answer does not seem to address the issue with Subdivision Surface modifier described  in the question.

It does as separated pyramids are not gonna be smoothed with the rest. And that's what the guy wants. Can't you put two and two together? Now, kindly upvote me please.

You will have a surface full of holes then. The differences between subdivided and lower detail parts tend to be visible. That does not seem like a very good solution.

The most direct method is to just use poke faces.
If they are not extruding much and you don't need a close-up shot, it might be a better idea to do it with a normal map.

You might consider separating the geometry into two meshes.
One mesh keeps the subdivision surface (although you might have to crease it near the edges that got separated).
The other mesh applies the subdivision surface modifier, and then you use the Poke Faces tactic suggested by the other posters.
Alternately, increase the Crease factor of the edges of the pyramids so that the subdivision surface does not curve them at all.

Use Smooth Vertex tool on selected vertices. Or separate, by selection, pyramids, that are poked faces made with Alt+P ,and give the rest Smooth shading (Tools).


text:
How to update Blender's naming index thing (.001, .002, etc.) after joining objects
I've been trying to reuse certain parts of code as functions in my bpy scripts. But that means that the same bmesh will be created as 'my_bmesh.001' the next time I run that function. To deal with this, I join 'my_bmesh' with a different object, 'main_object' and then run the function again, hoping that it will notice that 'my_bmesh' doesn't exist anymore, because it was joined into 'main_object' thereby allowing me to avoid situations with .001 names. In one current case, where I make stairs using an add_stairs() function, that function makes 2 objects, 'stairs' and 'stairs_support'. At the end of the function, I join 'stairs_support' into 'stairs'. A different function runs that add_stairs() function twice, and here is where the problem happens. Since 'stairs_support' has already been joined to 'stairs', it no longer exists. Still, upon the next call to add_stairs(), instead of the new bmesh being named 'stairs_support', it would be named 'stairs_support.001' so when the script looks for 'stairs_support' to join it with 'stairs', it returns the error:
"KeyError: bpy_prop_collection[key]: key 'stairs_support' not found"
For now, I just have to check myself that the original object already exists, so it knows to go with the 'stairs_support.001' name, but I don't want to have to make something like a for-loop that goes until it figures out what number mesh the counter has gone up to. I know that the counter restarts when Blender starts up again, but I can't just restart Blender mid-script. How do I refresh this counter, after I join 'stairs_support' to 'stairs'? Or perhaps there is some other means of combating this issue without dealing with the naming counter?
My original script is full of 1AM math that somehow just works, so to keep the code as readable as possible, I created a new script in under 200 lines of code that demonstrates the issue I'm having.
Here is the script:
import bpy
import bmesh
from bpy_extras import object_utils

def add_box(width, height, depth, self, context):

    verts = [(+(width / 2.0), +(height / 2.0), -(depth / 2.0)),
             (+(width / 2.0), -(height / 2.0), -(depth / 2.0)),
             (-(width / 2.0), -(height / 2.0), -(depth / 2.0)),
             (-(width / 2.0), +(height / 2.0), -(depth / 2.0)),
             (+(width / 2.0), +(height / 2.0), +(depth / 2.0)),
             (+(width / 2.0), -(height / 2.0), +(depth / 2.0)),
             (-(width / 2.0), -(height / 2.0), +(depth / 2.0)),
             (-(width / 2.0), +(height / 2.0), +(depth / 2.0)),
             ]

    faces = [(0, 1, 2, 3),
             (4, 7, 6, 5),
             (0, 4, 5, 1),
             (1, 5, 6, 2),
             (2, 6, 7, 3),
             (4, 0, 3, 7),
            ]

    mesh = bpy.data.meshes.new("Object1")

    bm = bmesh.new()

    for v_co in verts:
        bm.verts.new(v_co)

    bm.verts.ensure_lookup_table()
    for f_idx in faces:
        bm.faces.new([bm.verts[i] for i in f_idx])

    bm.to_mesh(mesh)
    mesh.update()

    # add the mesh as an object into the scene with this utility module
    object_utils.object_data_add(context, mesh, operator=self)

    width += 1.0
    verts = [(+(width / 2.0), +(height / 2.0), -(depth / 2.0)),
             (+(width / 2.0), -(height / 2.0), -(depth / 2.0)),
             (-(width / 2.0), -(height / 2.0), -(depth / 2.0)),
             (-(width / 2.0), +(height / 2.0), -(depth / 2.0)),
             (+(width / 2.0), +(height / 2.0), +(depth / 2.0)),
             (+(width / 2.0), -(height / 2.0), +(depth / 2.0)),
             (-(width / 2.0), -(height / 2.0), +(depth / 2.0)),
             (-(width / 2.0), +(height / 2.0), +(depth / 2.0)),
             ]

    faces = [(0, 1, 2, 3),
             (4, 7, 6, 5),
             (0, 4, 5, 1),
             (1, 5, 6, 2),
             (2, 6, 7, 3),
             (4, 0, 3, 7),
            ]

    mesh = bpy.data.meshes.new("Object2")

    bm = bmesh.new()

    for v_co in verts:
        bm.verts.new(v_co)

    bm.verts.ensure_lookup_table()
    for f_idx in faces:
        bm.faces.new([bm.verts[i] for i in f_idx])

    bm.to_mesh(mesh)
    mesh.update()

    # add the mesh as an object into the scene with this utility module
    object_utils.object_data_add(context, mesh, operator=self)

    #THE WAY IT CURRENTLY FAILS:
    bpy.data.objects['Object1'].select=True
    bpy.data.objects['Object2'].select=True
    bpy.context.scene.objects.active = bpy.data.objects['Object1']
    bpy.ops.object.join()
    bpy.data.objects['Object1'].name = 'Final_object'

    #TO MAKE IT WORK, COMMENT OUT THE ABOVE (ALL LINES FROM 79 TO 83) AND UNCOMMENT THE SECTION BELOW:
    """
    #Join them and rename them
    bpy.ops.object.select_all(action='DESELECT')
    if bpy.data.objects.get('Object1') is not None:
        bpy.data.objects['Object1'].select=True
    else:
        bpy.data.objects['Object1.001'].select=True
    if bpy.data.objects.get('Object2') is not None:
        bpy.data.objects['Object2'].select=True
    else:
        bpy.data.objects['Object2.001'].select=True
    if bpy.data.objects.get('Object1') is not None:
        bpy.context.scene.objects.active = bpy.data.objects['Object1']
    else:
        bpy.context.scene.objects.active = bpy.data.objects['Object1.001']

    bpy.ops.object.join()

    if bpy.data.objects.get('Object1') is not None:
        bpy.data.objects['Object1'].name = 'Final_object'
    else:
        bpy.data.objects['Object1.001'].name = 'Final_object'
    """

from bpy.props import (
        BoolProperty,
        BoolVectorProperty,
        FloatProperty,
        FloatVectorProperty,
        )

class AddBox(bpy.types.Operator):
    bl_idname = "mesh.primitive_box_add"
    bl_label = "Add Box"
    bl_options = {'REGISTER', 'UNDO'}

    width = FloatProperty(
            name="Width",
            description="Box Width",
            min=0.01, max=100.0,
            default=1.0,
            )
    height = FloatProperty(
            name="Height",
            description="Box Height",
            min=0.01, max=100.0,
            default=1.0,
            )
    depth = FloatProperty(
            name="Depth",
            description="Box Depth",
            min=0.01, max=100.0,
            default=1.0,
            )
    layers = BoolVectorProperty(
            name="Layers",
            description="Object Layers",
            size=20,
            options={'HIDDEN', 'SKIP_SAVE'},
            )

    # generic transform props
    view_align = BoolProperty(
            name="Align to View",
            default=False,
            )
    location = FloatVectorProperty(
            name="Location",
            subtype='TRANSLATION',
            )
    rotation = FloatVectorProperty(
            name="Rotation",
            subtype='EULER',
            )

    def execute(self, context):

        add_box(self.width, self.height, self.depth, self, context)
        add_box(self.width, self.height, self.depth, self, context)

        return {'FINISHED'}

def menu_func(self, context):
    self.layout.operator(AddBox.bl_idname, icon='MESH_CUBE')

def register():
    bpy.utils.register_class(AddBox)
    bpy.types.INFO_MT_mesh_add.append(menu_func)

def unregister():
    bpy.utils.unregister_class(AddBox)
    bpy.types.INFO_MT_mesh_add.remove(menu_func)

if __name__ == "__main__":
    register()

And a test .blend file:

I'm using Blender 2.79, if that makes a difference.

It would be far easier to help  if you included your script rather than a description of your script.

Let me know if the link to the script doesn't work. I've never really had to do this before.

Based on your original script the following changes 4 lines to store your newly created mesh data in variables that can be accessed instead of the name. The other changes are primarily with regards to pep8 compliance and removal of alternative method from your original code. It is likely that this can be improved upon. Furthermore the use of join will create orphan data that will be removed on save/reload of file may become excessive after multiple uses of the command. Also it was unclear as to whether or not you intended to have the execute duplicate the command so that was left as found.
import bpy
import bmesh
from bpy_extras import object_utils
from bpy.props import (
        BoolProperty,
        BoolVectorProperty,
        FloatProperty,
        FloatVectorProperty,
        )

def add_box(width, height, depth, self, context):

    verts = [(+(width / 2.0), +(height / 2.0), -(depth / 2.0)),
             (+(width / 2.0), -(height / 2.0), -(depth / 2.0)),
             (-(width / 2.0), -(height / 2.0), -(depth / 2.0)),
             (-(width / 2.0), +(height / 2.0), -(depth / 2.0)),
             (+(width / 2.0), +(height / 2.0), +(depth / 2.0)),
             (+(width / 2.0), -(height / 2.0), +(depth / 2.0)),
             (-(width / 2.0), -(height / 2.0), +(depth / 2.0)),
             (-(width / 2.0), +(height / 2.0), +(depth / 2.0)),
             ]

    faces = [
        (0, 1, 2, 3),
        (4, 7, 6, 5),
        (0, 4, 5, 1),
        (1, 5, 6, 2),
        (2, 6, 7, 3),
        (4, 0, 3, 7),
        ]

    mesh = bpy.data.meshes.new("Object1")

    bm = bmesh.new()

    for v_co in verts:
        bm.verts.new(v_co)

    bm.verts.ensure_lookup_table()
    for f_idx in faces:
        bm.faces.new([bm.verts[i] for i in f_idx])

    bm.to_mesh(mesh)
    mesh.update()

    # add the mesh as an object into the scene with this utility module
    # and assign to variable
    obj1 = object_utils.object_data_add(context, mesh, operator=self)

    width += 1.0
    verts = [(+(width / 2.0), +(height / 2.0), -(depth / 2.0)),
             (+(width / 2.0), -(height / 2.0), -(depth / 2.0)),
             (-(width / 2.0), -(height / 2.0), -(depth / 2.0)),
             (-(width / 2.0), +(height / 2.0), -(depth / 2.0)),
             (+(width / 2.0), +(height / 2.0), +(depth / 2.0)),
             (+(width / 2.0), -(height / 2.0), +(depth / 2.0)),
             (-(width / 2.0), -(height / 2.0), +(depth / 2.0)),
             (-(width / 2.0), +(height / 2.0), +(depth / 2.0)),
             ]

    faces = [
        (0, 1, 2, 3),
        (4, 7, 6, 5),
        (0, 4, 5, 1),
        (1, 5, 6, 2),
        (2, 6, 7, 3),
        (4, 0, 3, 7),
        ]

    mesh = bpy.data.meshes.new("Object2")

    bm = bmesh.new()

    for v_co in verts:
        bm.verts.new(v_co)

    bm.verts.ensure_lookup_table()
    for f_idx in faces:
        bm.faces.new([bm.verts[i] for i in f_idx])

    bm.to_mesh(mesh)
    mesh.update()

    # add the mesh as an object into the scene with this utility module
    # and assign to variable
    obj2 = object_utils.object_data_add(context, mesh, operator=self)
    # by default obj2 is both selected and active

    obj1.select = True

    bpy.ops.object.join()
    context.active_object.name = 'Final_object'

class AddBox(bpy.types.Operator):
    bl_idname = "mesh.primitive_box_add"
    bl_label = "Add Box"
    bl_options = {'REGISTER', 'UNDO'}

    width = FloatProperty(
            name="Width",
            description="Box Width",
            min=0.01, max=100.0,
            default=1.0,
            )
    height = FloatProperty(
            name="Height",
            description="Box Height",
            min=0.01, max=100.0,
            default=1.0,
            )
    depth = FloatProperty(
            name="Depth",
            description="Box Depth",
            min=0.01, max=100.0,
            default=1.0,
            )
    layers = BoolVectorProperty(
            name="Layers",
            description="Object Layers",
            size=20,
            options={'HIDDEN', 'SKIP_SAVE'},
            )

    # generic transform props
    view_align = BoolProperty(
            name="Align to View",
            default=False,
            )
    location = FloatVectorProperty(
            name="Location",
            subtype='TRANSLATION',
            )
    rotation = FloatVectorProperty(
            name="Rotation",
            subtype='EULER',
            )

    def execute(self, context):

        add_box(self.width, self.height, self.depth, self, context)
        add_box(self.width, self.height, self.depth, self, context)

        return {'FINISHED'}

def menu_func(self, context):
    self.layout.operator(AddBox.bl_idname, icon='MESH_CUBE')

def register():
    bpy.utils.register_class(AddBox)
    bpy.types.INFO_MT_mesh_add.append(menu_func)

def unregister():
    bpy.utils.unregister_class(AddBox)
    bpy.types.INFO_MT_mesh_add.remove(menu_func)

if __name__ == "__main__":
    register()

I checked it out, and your script gives exactly the output I was hoping to find, thank you!


text:
Easy way to model spiral engraving (knurling) that is usually used on metal for better grip?
What is the easiest way to model this diamond grip pattern into a cylinder?

https://blender.stackexchange.com/questions/58959/how-to-model-braided-nylon-sleeve

In case it helps, the pattern is usually called knurling: https://en.wikipedia.org/wiki/Knurling

Subdivide the area you want to engrave to have enough supporting geometry:

Subdivide it one more time - W > Subdivide:

Unsubdivide - Ctrl+E > Unsubdivide, choose Iterations: 1 in operator properties:

Select single face and select similar - Shift+G > Area:

Poke faces Alt+P and switch to vert select:

Select these 2 vertices:

Select similar - Shift+G > Amount of connecting edges:

Scale these in with Alt+S:

Mark sharp smoothing on the whole area.

You could achieve this with normal mapping in Blender. Use a normal map like for an example this:
Normal map
You can then in cycles create a material which uses the normal map to simulate the light bouncing of in certain ways to achieve this effect. You will have to UV unwrap the model, and assign the material with the normal map on the places you want it.


text:
GPU running "Very High" during render
Starting yesterday, 2.8 began running very 'hot' on my GPU. Task manager shows GPU running between 98 and 100%. In fact when clicking render view in the view port, the program has begun crashing - regularly, like almost every time.
This is sudden. I've never had this problem with any version of blender. Not sure if it's Windows 10 (which I strongly suspect) or a bug in blender.
Is anyone else experiencing this problem? Any suggestions/solutions?
Thanks very much.
Blender 2.8 ran perfectly until yesterday. Both the Beta and the "stable". 2.79 ran without a hitch as well. At this point it doesn't matter what I'm doing. Whether in the view port or rendering, the program's performance drags;the task manager fluctuates between low, high, and very high (100%) GPU usage. I did a windows 10 reset an hour ago, in the hopes that, that would fix the problem. I performed a fresh install of 2.8, but still it's slow and crashes. Again, I've never had a problem like this with Blender. I've always been impressed by it's stability. So, this all comes as a bit of a shock.

Did you use Blender 2.8 before without encountering any issues? Is the GPU usage that high when just using the interface or during rendering?

Thanks for commenting. Yes Blender 2.8 ran perfectly until yesterday. Both the Beta and the "stable". 2.79 ran without a hitch as well. At this point it doesn't matter what I'm doing. Whether in the view port or rendering, the program's performance drags;the task manager fluctuates between low, high, and very high (100%) GPU usage. I did a windows 10 reset an hour ago, in the hopes that, that would fix the problem. I performed a fresh install of 2.8, but still it's slow and crashes.
Again, I've never had a problem like this with Blender. I've always been impressed by it's stability. So, this a

Did you make sure the GPU drivers are up to date? Wrong GPU drivers could cause this. Or it could even be that Windows updated them automatically to a version containing some bug. What is the GPU model in question? Could you maybe edit the question and provide the specs for the PC? That might be helpful.


text:
Sidebar "Item" Tab has Disappeared
I've been using Blender for a couple of weeks now, and things have been going well until today when the "Item" tab in the sidebar suddenly wasn't there any longer. (See screenshot)
I've looked through the manual to see if there's an option and keymaps for hiding and showing sidebar tabs that I might have triggered by accident but I wasn't able to find anything like that. Nothing useful came up from a general Google search either.
Any advice or assistance would be appreciated.

Hello. By default this panel only appears when you have an object selected in the viewport. Otherwise, try disabling your addons one by one and see if it reappears when one of your addons is disabled.

To be more precise, as @Gorgious said it is there when you have selected an object in the viewport. Although, after you've deselected all objects the Item tab usually stays there, as does the origin of the last selected object and the Properties Editor still shows its properties. However if you delete the selected object then there is no more origin or properties to be shown since the object does not exist anymore. In this case the Item tab is hidden until you select another object.

Thanks for responding. I was seeing this issue when an object was selected, but only immediately after opening a file, so you can understand my confusion. Now I know I have to unselect whatever is selected when a file is opened.


text:
Transform frame of particles sim into object
I want to make this exact frame of the simulation an mesh object so I can append into another file, how do I do that? I searched and didnt find an answer.Its a plane using explode modifier with particles simulations.

You can "apply" the explode modifier when positioned at the frame you want.


text:
How to determine whether blender background rendering has ended？
For example, I want to automatically shut down my computer after the background rendering is completed, the command I used is
start blender -b "path to the project file" -E BLENDER_EEVEE -o//"exported path" -a
I need to add start at the front, otherwise Blender will enter a pseudo death state after execution. However, with start added, the system will open an additional backend process for Blender to perform rendering operations.
But I don't know how to listen to this process, and when I try to use the subprocess module in Blender Python, it reports an error, The last line in the traceback says:
FileNotFoundError: [winError 2] The system cannot find the specified file
Does anyone know how to solve this situation?
Thanks

Can you show the code which produces the FileNotFoundError?

A couple other things that look fishy in your example command:

-o//"exported path" the whole path should be inside the quotation marks: -o "//exported path"
start shouldn't be necessary, its only purpose is to run a process so that you keep the control of the console instead of waiting for the process to finish. But if you use Blender's CLI correctly, it should return control when done processing AFAIK.

Other than that, I'm a bit confused because, officially:

There is currently no support for using Eevee on headless systems (i.e. without a Display Manager).
Sourbe: Limitations — Blender Manual

This means, unless you fake a display (like shown here), you can't render in command line with Eevee. So you should use CYCLES instead.
And, practically, I haven't seen anyone render using Eevee or Workbench otherwise. But I just did some tests and it... Works?
But I'm using Windows 11's "Terminal" application, and with some addons (clink, wsl2 for GUI Linux, ...), so maybe that's why.


text:
Best way to move scale pivot with mirror modifier
There are times when I'm box modeling with a mirror modifier where I want to scale a face from the center axis (that I'm mirroring over) NOT the center of the face.
Currently I'm doing this:
Enter Edge Selection Mode and select and edge on the center axis
Shift - S to snap 3d cursor to edge
Use S then X to scale on just the single axis
Is there an easier way to do this?
Thank you.

To do this:

Switch to edit mode

Switch to edge selection

Select required edge

Shift+S --> cursor to selected

Result:

@lawrencehagman You are welcome, I've updated my answer and included screenshots. Please accept it if it solved your problem.


text:
Need Help with Intro Animation
I have some experience with Blender but not with animation or text.
I'm looking to make an intro for my Youtube channel and have the vision but not the means. I've skimmed through some tutorials but the way my vision starts is too different for it to be much help.
My channel is very 3D print oriented so the intro goes as follows:
A 2D "E3D V6 print nozzle" moves along the screen, a bottom sliver of 2D text appears "from" it as it does. It moves up slightly and then along the screen in the opposite direction. The next up sliver of text appears "from" it as it does. This continues until the entire title is visible and "print nozzle" is at the top right. This takes 2-5 seconds.
Then the "print nozzle" disappears as a smoke spreads out from behind the text and into the surrounding screen. This decelerates. In the smoke are some "Bokeh lights" that follow the same action. This takes another 2-5 seconds.
Scene fades to black.
The text is a deep orange, the hot end a darker orange. The background is a very dark greenish blue, the smoke a bright neon blue and the bokeh lights a yellow.
If you need help envisioning the scene take a look at my channel art here.
Any help is appreciated! I'm not sure where to start. Thank you :)

This... is a fairly detailed animation. Text animatics, smoke physics, compositing... Getting the smoke right alone can be a mission. But I can get you started with one non-fluid dynamics approach on the text:
Type out and position your text on one layer. Model some overlapping 'lines' of deep orange FDM-approved 'plastic' on a second layer. Position the nozzle on a third layer. Set up some masking planes for the plastic on a fourth layer. Animate the nozzle to zigzag over the text. As the nozzle moves, the appropriate mask moves to 'reveal' the plastic coming out.
In the compositor you'll want to set up your renderlayers and nodes in such a way that:

Masking planes hide the plastic. If you're working in Cycles you can do this fairly simply with the Mask Layer options for the masking planes.
Plastic layer pixels are visible if there are text pixels overlapping them. Stick an Alpha Over node between the Text and Plastic renderlayer outputs.

Again, this is a high-level overview and just one of many approaches you could use. Good luck :)


text:
Version 2.78, gtx 1080, Cycles Render, Rendered Viewport, Black Screen
My issue is when using Blender 2.78, my screen will flicker and go black in portions, whenever I enter rendered in the viewport (Shift+Z). This happens whether blender is the only application running or not, but if I have a video playing on the other monitor (my Blender course), the web page will often freeze, reload, or otherwise be wonky.
I am using an NVidia GTX 1080 (I believe it has 8 GB of memory), windows 10 64 bit, 16 GB of memory, and an Intel 6700k processor. I'm rendering with GPU compute. I also have a GSync monitor with GSync running.
The problem happens often, but not all of the time. To fix it, I have to move the mouse around the screen, or move the window itself.
Since pascal GPU compatibility was just recently added for cycles render, I thought maybe it could be a bug with the software, but I don't see anyone having a similar issue.
Below are images of the problem (working fine, black screen effect):

May be an issue with GSync, have you tried turning it off? May be a driver issue, overheating, a faulty GPU memory or  simply a Blender bug, Hard to tell

With GSync on or off, and with the new driver I just installed, the issue persists. I'm not really sure how to deal with, or even check my GPU memory.

Page freezing and weird behavior for other opened applications is expected while GPU rendering though, since the device is busy processing the scene it can't keep up with much more heavy stuff in parallel.

Also, Blender frequently crashes in cycles render using GPU compute. I tried running from command prompt with -d, but there was no message of why it crashed, and I saw no temp file for the crash.

I'm upvoting this because last night I encountered this as well. I'm on GTX 1060 running Blender 2.78. That was the first time I'd seen it happen over the past two weeks (I've only been using Blender for 2 weeks now). Except for GPU, your system sounds very similar to mine, and I'm seeing it as well.

Also, I switched to a GTX Titan (Pascal, so it's the same 10 series), and the issue persists, including the crashes.


text:
Can Blender do mathematical reservoir simulation for petroleum engineer?
Can Blender do reservoir simulation like Petrel Schlumberger and CMG do for petroleum engineer?
I'm a student of petroleum engineering, and I love Blender more than my girlfriend.
Like this :

No. Blender is not designed to run scientific simulations. You will need to find another tool for the job. There are no tools designed for that in Blender and if you wanted to script them in Python using Blender's Python API you should also consider that Blender mostly stores data as 32 bit floats that might not be ideal for any scientific applications where precise calculations are important.


text:
Is there any way to import a .json model into Blender?
I need to find a way to import some .json models into Blender, and it seems I can't just import them the same way I can import a .obj model. So is there some way to convert a .json model to a .obj model, or another file type Blender can import? I've tried using Blockbench for this, but I think it only works with Minecraft recourse pack .json models, as those are the only models that will ever actually load in it. Thank you to anyone who can help me figure this out.

Have you found this addon here? https://github.com/warmwaffles/io_mesh_json and here with https://www.barneyparker.com/blender-json-import-export-plugin/ comments

Have you found this addon here? https://github.com/warmwaffles/io_mesh_json and here with https://www.barneyparker.com/blender-json-import-export-plugin/ comments

@ZDUDE9 Please accept this answer with the green checkmark if it helped you.

the first link is only for exporting, and the second is a 404.


text:
How to fill a grease pencil ring?
I have two nested circles which build a ring.

What I want to do is fill the ring and leave the inner circle transparent(I don't want to fill it with another color, I want background to become visible). But when I try to fill the ring, inner circle fills as well.

How can I make the inner circle transparent?

I don't really do grease pencil stuff but I'm guessing the outer and inner circle need to be in the same layer

Thanks @Motcho to reminding me but I tried it as well. I got same result when put them inside a layer.

Hi, Makan. I hope you don't mind my edit.

Your edit was really helpful @MartynasŽiemys Thanks!

UPDATE: As of version 2.91 we now have a Holdout option in the material settings which makes life much easier:

Create a new material, check Fill and Holdout
Use the paint bucket to fill in any area you want to be see-through, or just draw the inside of the ring using this material.

Old answer:

Create a new layer and name it "hole"

Draw a filled circle matching the ring's inner circle

Turn down the opacity of the "hole" layer to 0.000

Switch to the fill layer (that filled the entire ring) and enable mask

Add "hole" to the mask list and invert it by clicking on the square/circle icon

Thanks @wilks I added a new GP layer on top of other layers, then filled the inner circle with blue and finally set the blend mode of the new layer to Subtract at this time the inner circle became a shade of red.  Then I set the opacity of layer to 0 but again inner circle became red. I guess your answer should be correct and I might be do it in a wrong way. Could you please explain it a bit more?

sure, gimme a min to add some screenshots, should be clearer

dang, can't get substract to work anymore =( i must have changed some settings when i tried the first time. But i managed to make it happen with masks, updating my answer now

It works!!! @wilks you saved me! Thanks!!!

@Makan Great! you can accept the answer then


text:
What is snapping in Blender and how to use it properly?
I am reading the Blender manual and I have come in contact with snapping a lot. I don't know what it means and also how to use it properly. I need help.

Snapping is when you use the position or even orientation of something else in some operation to align/snap/move to/scale to/rotate to something that you are editing with that operation.
Blender has loads of various great snapping functionality.
Snap Menu
There is this snap menu that you can call with Shift+S:

Snapping in Transform Operations
And then there is also snapping in transform operations that depends on all these settings of your Transform Orientation and constraining of the transform operations or Axis Locking, Transform Pivot Point and Snapping Settings. These work in so many ways, that it would be hard to describe them all. You can find out more about it in the manual that you are reading and the links to it that I put in this answer, but the basic idea is that you combine all of those settings to make snapping situation that you happen to need. For example if I want to snap the center of Suzane's eye to the vertex of the point of the cone in my scene, one of the many ways to do that could be to set the Transform Pivot to the 3d Cursor, Snapping to Vertices and Snapping target to Center, this way, I could drag the cursor with Shift+ right-click, hold Ctrl down to enable snapping for it and snap it to the vertex on the eye, and then use grab G transform operation to snap the place the cursor was at to the vertex I hover my mouse over:

But you can see that there are many settings there and they will all work differently in combination with each other, you can also use rotation and scale transforms with various ways of snapping, and also you can use a to snap to multiple targets(you need to temporarily release Ctrl to press a if you are using it to only temporarily enable snapping during transform operation)
You will eventually get the feeling of what you need when you get familiar with all the settings, you should just try them out, and of course you will find it very well documented in the manual.


text:
Is there a hotkey to subdivide geometry?
I’ve been following this tutorial for a model, and I’m wondering if there’s any hotkey to change an extruded plane (like it was done in the video) from this:

To this:

If not, do I need to use a cube mesh and edit it?

hit w then s whiich will subdivide the plane

@mathmaniage That sounds like an answer, care to write one?

For Version 2.9
In edit mode, right-click, then S is a quick way to do it using only the default key bindings.
Additionally, it also appears to be the first entry in the list (screen space permitting) and you can just do right-click then left-click.

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

in my case it's set to alt + w

The W shortcut works only for versions previous to 2.8

To subdivide simple go to edit mode and hit W and then S.
To subdivide like the catmull clark go to edit mode and hit W then U after you select the required mesh geometry.

The W shortcut works only for versions previous to 2.8

Just found out, there is a better way. In edit mode, right-click, then again right-click on "Subdivide" menu entry. Now you can assign whatever hotkey you like. Obviously this works with other menu entries as well. You just have to be lucky to find a key which is not already occupied by Blender. ;-)


text:
Issue with lighting and rendered environment map
I'm trying to create a simple environment map for a Unity game I'm working on but I'm getting weird lighting issues, it seems like the lighting for each face is rendered differently. I'm using Blender Render in Blender v2.76.
I've added the map as a skybox in Unity which displays the problem:

I've created a very simple scene that displays the problem, it only has a few objects in a single mesh with a couple of lights. An empty above center is used as the Viewpoint Object.
The environment settings are using the static map defaults except that I've switched to Equirectangular coordinates.

Above is the environment map output though rearranged so the faces to connect to make the problem more obvious. Last two faces are bottom and top respectively, notice how the bottom is much darker than the plane is in the other faces as well.
Why am I getting this odd lighting behavior?
Example file:

Could you upload a .blend file to http://blend-exchange.giantcowfilms.com/

Absolutely, you can get it here.
I'm unable to add more than two links to the post (those two pictures count as two) so I can't update the post with the link, if someone update it I'd be thankful.

Ok, seems like I got the reputation for updating the question, fixed now.

Is your final image a result .exr file shown in Cycles or imported into Unity ? How did you make your hdri map ? For info about creating hdri from render see http://blender.stackexchange.com/questions/13853/create-hdr-map-from-render (if Cycles).

I'm using the Environment Map-texture functionality in Blender Render, so not using Cycles at all (Environment Maps are only available in Blender Render). The output is a PNG-file, shown at bottom with rearranged order of faces, while the first image in the question is the map applied as a skybox in Unity.
I've pretty much done what is shown here, more info about environment maps is available here

I believe your issue is that you are using the Blender Render engine instead of Cycles (much newer). This would definitely lead to the darker bottom faces because Blender Render does not utilize bounce lighting (in real life, if you have a desk with a cavity under it and a white carpet floor for example, when photons hit the carpet, they bounce and also hit the underside of the desk, illuminating it). Blender Render also cannot do proper environment maps.
To fix all of these problems, go to the top bar and where it says Blender Render, instead select Cycles Render from the dropdown:
 -->
Select the camera and go to the Camera Object Data tab in the Properties panel. Change the settings under Lens to Panoramic and Equirectangular. This will create a true world image.

Go to the Render Settings tab in the Properties panel. Under Light Paths, change the settings to these. These are the optimal bounce lighting settings that I use in almost every render. While on the subject of lighting, I would highly recommend repositioning your lamps and changing their strength and color so that the image looks better.

Go to Properties panel > Render Settings > Sampling and change the Render: samples to 250. Also change the Clamp Indirect: value to 3. Both of these will improve your image's clarity.
Go to Properties panel > Render Settings > Dimensions and change the X: and Y: dimensions to 2000x1000. Up the percentage slider to 100%.

Lastly, since I assume you want a panorama like this:

...and not like this:

...change your camera positioning in the 3D View Properties panel to this:

After adjusting the lighting as well, I was able to make this:

Also, here is the adjusted .blend file:

Thank you for the very detailed answer! I was looking to make a 6-sided cubemap but your solution works too if I switch to a cylindrical map in Unity. And using Cycles is just better obviously, I was using Blender Render because the Environment Map feature is only available with that renderer. Which is why I'm a bit perplexed when you say that Blender Render cannot do proper environment maps... are you saying that feature is broken or deprecated? This is the functionality I'm talking about.

Oh, and regarding the lighting, this is not actually the scene I'm working on; it was just a barebones example scene to show the issue I'm having. But thanks for pointing it out anyway!

@SvDvorak Glad to help. I was not aware of that functionality in BI. Perhaps you are correct. I use Cycles because it's more updated, and I haven't found many tutorials to teach me BI. Also, the environment maps in Cycles just seem easier.

I kinda figured, that functionality is a bit hidden though it was the only I found for creating a cubemap. Creating an actual cubemap using Cycles is a lot trickier, you have to render an animation with a rotating camera and then compose the images together. But using a cylindrical skybox with your solution is so much easier while letting me use Cycles.


text:
variance lamp alpha
I need to use a variance buffer shadow sunlamp to illuminate a scene in the game engine yet I have not succeed in obtaining correct shadows from my alpha planes as you can see in this picture. Is it possible ?

here's the blend

Variance lights do not support alpha channel. I'm not sure why. Simple shadows do (as pointed out in one of the other answers), but as you have discovered, variance shadows do not.
To enhance the effect of a bigger shadow area, you can vertex-parent the sun to the player, so it follows them around. This way you can get a 512x512 shadow map to appear to cover the entire map.
Sorry I can't be of any further help.

If you are looking for what is in the image you have posted, then bumping up the sun value to 6000 gave me this:

Otherwise:
my understanding of your intent, is that you wanted the shadows to match the shape of the Leaves, like the following image.

The biggest for me was to do two primary things:

Make sure that my Leaves had a true Alpha Channel (not just Black to Alpha)
Changing shadow type from Variance to Simple on the Sun Lamp.

Note In the viewport this does not work, but in game it works.
Here's the blend so you can cruise around and match any settings I messed with, just in case I missed something, plus I also packed my horrible version of a leaf texture image in here for you to make sure you have a visual reference to understand what I mean regarding the Alpha Channel.

your shadows here are well but they are emited from a simple buffer shadow lamp and I wanted to be able to use the variance buffer for that purpose because when you are working on big scale with 1000 trees you need a resolution buffer that is not affordable to produce correct shadows in real time, so I was hoping I could trick the result by having lower resolution shadows but still the effect of gradient you get with variance lamp.

So is the image that you posted your desired result or your problem?

@Yvain, I modified my answer to address both cases anyway.

Under the game settings tab located in the material editor enable Alpha blend
If this does not work try using a Hemi light source instead of a sun lamp.

I tried with every kind of alpha it won't fix the situation, hemi doesn't produce buffer shadows, only sun and spot do.

Maybe you could include a .blend file.
It makes it a lot easier for people to help solve the problem.


text:
How do I change the default Blender controls to allow for left click drag/box select? Like in the Maya preset controls
When you use the Maya preset controls scheme left click and dragging allows you to use a drag/box select but in the default Blender control scheme left click and dragging edits the geometry of the mesh. How would I change the Blender controls to allow for left click to be drag/box select?

Press Shift + B for the box select tool

I did figure that out, however it is slightly different than the left click preset for the maya controls. But If I cant figure it out I may just have to start using the Shift + B version.

This is the default for Blender 2.8, so you could just upgrade to that right now and it would solve your problem.

When trying to figure out the changes between presets, it's actually quite easy to reverse engineer once you know how. In the user preferences, navigate to the input tab, and (searching for Name, not Key-Binding) search for Border, and find the one under the 3D View heading. This is the one we'll need to modify. If you compare the differences between the two presets, you can figure out what's been changed.
By default, Border Select is mapped to the B key. Switch it from Keyboard to Tweak, and change it from Left to Select. If you want the exact behavior of the Maya preset (as in selecting with Border Select replaces the selection instead of extending it) simply disable the Extend option.
Here's an image of the original setting:

And here's the adjusted settings:

You may need (or want) to further emulate the Maya preset, in which case there are the Gesture Border settings located just below the main settings. These will affect how the tool behaves once you've activated it. You may have to play around with these to find a method that works with the default setup.
Here's how the Gesture Border settings are setup for the Maya preset:

Don't be afraid to play around with the inputs either. Once you edit the input for a tool Blender gives you an option to reset it back to whatever preset you're using.

Open Blender, go to the splash screen, click on interaction, then on the drop-down menu, press Maya.


text:
How can I improve this?
I'm very newbie on Blender and also on design/ilustration, but on this quarantine I decided to learn it as a curiosity :)
I created this house from Midsommar, but I didn't like the result at all, it seems that it lacks some volume.

How do you think I could improve it and how to do it?
I thought about creating some shadow between the house and the green plane (ground) to create a separation, but I dont know how to do it...
Any help/tip, please?
Thank you so much!

Welcome to Blender SE! For the "seperation", try searching for ambient occlusion

Hello :). As @Jonas commented, enable AO in Render Tab > Ambient Occlusion. It will add shadows into corners and ridges.

It is hard to answer this question based on facts without involving personal opinions which is the goal on this platform, but let me try...
Keep working on it
Well... it's a fact that it will get better eventually if you keep working on it. Many beginners have works that look very similar to what an experienced 3D artist would consider to be just a sketch or just a rough start and just stop working on them and that's how they fail to create an impressive image. So don't do that. Don't stop. Just keep working.
Things to consider
Now it is also a fact that there are many things to consider when creating an interesting, aesthetically pleasing image. If I told you what to change it would be my opinion, but the existence of these things is a fact the way I see it. So here it goes, some of them are:

The context. Why are you making it? Who will see it? How? In what medium.
The idea. What do you want to communicate with the image. What's the message if there is one. What mood should it form?..
Composition. Balance or imbalance. Places of objects or visual elements in relation to each other, directions viewers eyes move or are guided when looking at it and so on...
Focal point. What is the main subject. How you lead to it, separate it, make it special. Depth - whats background, foreground, layers of depth...
Patterns and groups, detail, cognitive ease while looking at it, distribution of shapes and stuff like that. This is interesting: https://www.youtube.com/watch?v=qMH_J_vcoqE
Color. Color theory... Don't even know where to begin here. Google maybe :)
Lighting. We have the luxury of creating absoolutely any type of lighting in 3d. That's a very powerful tool.
Framing. Point of view. That changes a lot as well. Whose eyes/camera are you looking through? What perspective? How high, low, straight, angled and so on...
Style. Realistic? Stylized? Resembling something?
Believability/realism. Is the scale of your objects real, are the proportions believable? Are they detailed enough to be recognizable?..

I am sure there are many more, but maybe that helps at least a bit to just think about these things or imagine variations of them...

thank you so much!

First of all, your proportions are off. The well should be bigger compared to the house
Then your composition could be better ( a quick google search on basic principles for compositions will help you
Finally, play with your materials and colors
The grass looks too glossy for grass, and the sky has this interesting color :)
Of course you should follow what you want to do, maybe in your context the floor is plastic, etc.
Have fun with blender !


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Is it possible to delete backfaces as opposed to hiding them?
So I’m just starting out in Blender - I have 50+ textured and animated models (md3 format) which I didn’t make but need to fix up to render properly in a game engine.  I’ve managed to find md3 import/export scripts so have gotten over that first hurdle.
The issue I have is that my models don’t render correctly in a 3D game but in Blender look “correct” when I enable back face culling mode. Can my models be permanently fixed in Blender to in effect replicate this culling of back faces? If so I am sincerely hoping a more expert user can provide procedures on the step(s) involved?
I’m a complete newbie with Blender - I’ve tried to fix my models both in MilkShape 3D (was promising but removed all animations from my md3s) and Misfit Model 3D (no joy).  I’ve tried flipping normals and other tweaks without success.

Firstly, what game engine? secondly, an image in the game engine of what is wrong and images of the model in Blender including Riggs and normal direction in edit mode. I know that backface culling is automatic in unity, but if it is a different game engine, it may not do so. Maybe look into activating backface culling in your render engine.

It is impossible to delete backfaces, since they are only a concept in rendering algorithms - there is nothing to delete
Backface culling is a shading feature of the render engine that you are using. Back faces are not in any way stored with 3d data so there is nothing to delete. Backface is the back of a regular face that is determined by which direction the surface is facing or in other words - surface normals, that are definitely already included in your models when you export them from Blender or pretty much any other 3d app. No other information about back faces than surface normals is saved with the models so there is nothing more that can be done inside Blender. This features should be turned on or off in the game engine you are using. Backfaces might not be displayed by default in some rendering scenarios so it may also not be considered a feature at all, but actually the lack of another feature - backface shading, or double sided shading. It depends on how you look at it and how the shading works in a specific render engine.


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How to export Python animation to gltf from Blender 2.80?
I have some 3d objects that I use Python code to rotate. In the Blender preview this works fine.
How can I export the animation caused by the Python code to gltf? The normal gltf export exposes the objects but not the animation.

The glTF exporter is looking for animation keyframes in the NLA tracks for export.  If you have custom Python code that's just writing to the object transform on the fly, that's not going to be found by the exporter.  Your Python code will need to create actual animation keyframes, such that the exporter can read those keyframes and write them into the glTF file.