textures are not loaded with collada files I'm using Noesis to export Collada files and then import them into Blender 2.82 but the textures are not loaded at all. Is there a way to force the system to load textures?

.dae files do not contain any textures or texture information other than the (absolute or relative) path to those textures. It's actually quite the same as with many other texture formats (.obj or even .blend, if you choose not to pack your textures into the .blend file explicitly).

It's more of a Noesis question, that is, if Noesis is capable of exporting absolute or relative texture paths. Try to export the .dae file into the same folder that contains the textures. Also check if there are any settings for exporting UV layouts.

If importing the resulting .dae file still results in missing textures, you have to recreate the materials of the model in Blender.


Trying to create visualization of EM waves I'm trying to create a visual representation of EM waves traveling through space and I'm having a tough time.  I found these images I like but I am having trouble coming up with a good way to render them.  I'm using cycles and it is a still image so I don't need to worry about animating.

Thanks.

You can recreate the first image fairly well using the math function mesh (Add --> Mesh --> Math Function --> Z Math Function).

This is what we're aiming for here:

First, you need to enable the AddMesh:Extra Objects add-on (press CtrlAltU to access the system preferences)

Type in the wave function you want to display in the input box (I used Z = sin(x) + sin(y) for this example).

Then, delete the edges along one axis (I deleted the ones along X):

Select and add each edge loop using AltShiftRight Mouse Button.
After you've got 'em all, delete edges and faces only (X --> Only Edges and Faces).

From here you can take it to many different places, but here's a suggested workflow:

Convert the mesh to a curve, then add a fill.

Add a taper object (bezier curve with an arch shape along the Y axis), and set it as a taper object for the wave curve.

Add a subsurf modifier to get smoother curves.

In Cycles, set an emission material to the wave object and choose a proper color.

If you want to add particles for added effect, create another copy of the original wave mesh, then add a particle system to it.

Add a simple mesh circle (Add --> Mesh --> Circle).

Set Fill type: Triangle Fan

and Vertices: 6

Then rotate 90 degrees on X so that the circle faces the Y axis.

Apply rotation (CtrlA --> Rotation).

Apply the same material you created for the wave to this circle.

Use the following particle settings:

Emission:
Number: 50000
Jittering Amount: 2

Velocity:
Random: 2
Rot: 1

Physics:
Size: 0.025
Random Size: 1
Mass: 0

Render:
Emitter: False (uncheck)
Render type: Object
Dupli Object: The hexagonal circle you created earlier.
In the Scene tab on the Properties Window, turn Gravity off.

Run the animation (AltA) for a bit until you have a nice distribution of particles around your mesh.

That's about it!

You can enhance this further by adding depth of field or motion blur, but I'll let you find tutorials or other answers to find out how to do this.


How to create recesses in a curved surface? I want to make a simple cylinder box that has a very simple twist lock. I have seen a lot of maze puzzle boxes on the net but I just want something simple.

Ideally The lid will have 3 'L' shaped recesses in it that a lip with 3 pins in the base will key into. The lid presses down with the pins in the recess and then a twist to close.

The base would look something like this:

[Edit] I found the torus mesh. It seems like I need to play with some maths but this is kind of what I'm after, but without the continuous loop really (oh, and imagine a closed top).

Can anyone provide any good examples or links on how to do this easily.

Anything that has to be cut into a curved surface, I tend to build flat and curve into shape later. Using this method I have a model of one 'L' section and a bezier circle (origins of both objects matching each other):

Using an Array modifier with a count of '3', followed by a Subsurf set to '2' subdivisions and finally a Curve modifier:

I get this result:

Using modifiers allows you to easily manipulate the original non-curved section, while also seeing how it will look when curved into a circle.

Once you are happy, modifiers can be applied and the two ends of the circle can be merged (either by W> Remove Doubles, if the vertices are close enough, or more manual merging if they are not).

Also note that increasing the resolution of the curve on the curve's 'Data' tab will improve results. This example had a curve resolution of 30.


Whats the Blender 2.8 command for adding an object to a collection using python? I currently have a method that does:

self.myCol = bpy.data.collections.new(self.collection_name)
bpy.context.scene.collection.children.link(myCol)

This method creates and adds a new collection to the outliner. Next, I want to create a bunch of cubes and add those cubes to the collection. How can I tell blender to create objects only within that particular collection?

Something like:

bpy.ops.mesh.primitive_cube_add(collection='name', size=2, location=(0, 0, 0))

Obvious cube_add doesn't have the param for it, so what's the proper way to do this?

Your answer is actually wrong.

If your active collection is another as the main collection, when running your script the object will not be removed from this.

import bpy

bpy.ops.mesh.primitive_cube_add()
# our created cube is the active one
obj = bpy.context.active_object
# Remove object from all collections not used in a scene
bpy.ops.collection.objects_remove_all()
# add it to our specific collection
bpy.data.collections['MyCollection'].objects.link(obj)

About remove all:
https://docs.blender.org/api/blender2.8/bpy.ops.collection.html#bpy.ops.collection.objects_remove_all


Split a mesh with a plane I'm trying to split a mesh into two pieces along a plane like in this video, using Blender 2.62.

The closest I can come to splitting a mesh into two pieces along a plane is this:

Add a plane
Grab and move the plane to where I want the cut an existing mesh
Select the plane, then (and) the mesh
Apply a Boolean modifier

This indeed splits the mesh in two, but it tosses out one of the new pieces (intersection, difference, and union all do this, but they differ in which of the two pieces get lost). Is there any way that I can fix this problem with the Boolean modifier or another way for me to split my mesh?

My goal is to eventually write a script which splits an object into many equally-spaced slices along a given axis.

For the bit about them disappearing when you use a modifier, this is fairly simple enough, just duplicate the object and change the modifier Operation on one of them to Difference and on the other, set it to Intersect and target them at the same object that you want to use and split the other.

You should now have two separate objects and still be able to modify them via their unique boolean modifier, when you are satisfied, simply apply the modifier and separate them.

In the image below, I have two separate objects but each has a boolean modifier with the same target which is the plane (I have set its draw type to Bounds so the objects can be seen easier). I have also applied the boolean modifier to the top piece so I am able to separate it from the rest of the object.


Lighting not updating on every frame The lamps in this scene are stationary. Only the lit object is moving.

However, in this render, it seems like the lighting is being baked onto the object for several frames (perhaps 8 or 10) at a time, instead of being smoothly updated on every frame. Is that a bug?

If not, what could I be doing wrong?

Help greatly appreciated.

Thanks.

https://youtu.be/0drCC_cSPOc?t=4s

What render engine are you using to produce this animation, and what technique did you employ to make those 'bumps' or voxels in the surface?

Is it actual modeled geometry, or is it just bump mapping? Perhaps a or normal map or use of displacement?
How did you model the underlying sphere geometry?

It looks like it is updating lighting in real time, what you are seeing is just an artifact of smooth shading on a low number of subdivisions.

It looks like you are using an icosphere and since this sphere seems to have an insufficient number of subdivisions what you are seeing may be the result of Blender shading a larger flat face, and light just seems to 'stick' to it instead of accompanying the curved surface our eyes are led to believe is there through smooth shading.

With the rotating motion light just seems to jumps as reaches or stops reaching these large flat faces.

Can you post a blend file we can look at, it's hard to tell for sure just looking at the video. Or perhaps a wire-frame image of your viewport.

I would recommend trying to increase the number of subdivisions on the base geometry of your sphere and see if it improves.


How can I uniformly apply an image as a texture to an object? I'm trying to make an icosphere with a hexagonal pattern applied to it, but the image I'm using ends up getting completely warped and ripped along the faces. I don't know how to fix this, so please help.

You might want to try the node setup shown below. Change the parameters in the mapping node to move the image around. This might not work, as it is possible that the problem is in the UV projection, but I've already solved problems like this using this node setup.
I hope this helps.


Global Variable/Node across multiple materials? How can I get a Node input/output (e.g. a single Color/Value) that I can control from the one spot, but have mapped across multiple materials? For example, to control a value (say, Glass Shader IOF, or a Mix Shader Fac) across 30 different materials (that may or may not have different node setups, but all use the input I want as a driving factor somewhere inside).
I've got a few ideas so far, but am not sure which will work and/or which will be the best way to go about it:

Use a Node Group
I tried setting up an input inside a node group, then using the node group in various locations - however I could only seem to automate/keyframe the 'default' values of things inside the group (these changes didn't flow through into the instances of the group).

Script node
I could set up a Script Node that returns the value I want - however I imagine this would be tricky to automate, and it would also lock me into OSL, which feels a bit roundabout and also rules out GPU rendering (not essential but it would be nice)

Driver
I could set up a dummy object or material, set up drivers through to the things I want to control, then keyframe the dummy object and that might achieve what I want. However this again feels a bit roundabout/messy.

Background: I'm working on a model that has a non-trivial number of materials (just over 100, auto-generated from a 3D scanner), and am trying to set up effective backface culling in rendering by using the method described here. This involves scripting the addition and connecting of all the extra nodes (Mix shader controlled by Geometry Backfacing, and a Transparent BSDF node to make the faces be rendered transparent from the back), because doing it manually for all 100+ materials would be a pain. It's not essential, but I was thinking it would be nice to be able to control the overall effect by automating all the Transparent BSDF Alpha amounts - I'm just not sure how I'd go about controlling that from a single point though.

This can be done with node groups.

I think you were trying to edit the attributes of the node group instance itself. Instead, try editing/animating the attributes of the nodes inside the group:

Just add a value node (or any input nodes you want, e.g. RGB for color) and press ⎈ CtrlG to make it into a group.

Changes the values of the nodes inside the group will take effect everywhere the group is used, even across different materials. So in this case changing the value node will change the brightness of the diffuse material and the AO material.


How to make an object fit in a unit cube? In my blender object, there are hundreds of vertices, normals, faces and etc and the thing I want to do is to make it fit in a unit cube. I've tried almost everything including

Trying to find an option in file->export.
Selecting all the things using A button,
    assigning into one vertex group and
    pushing normalize all button in "Weight tools" pane.
Scaling the object somehow.

None of them works. So I need a little help. Please show me the way how to do it.

You can use this kind of script (works with the active object) :

Alternative script, so that :

Rotation and scale are previously applied (avoid border effects when export)
Place all the vertices between 0 and 1 (previous script only matters about overall dimensions)

import bpy
from mathutils import Vector

obj = bpy.context.object

#Eventually apply transforms (comment if unwanted)
bpy.ops.object.transform_apply( rotation = True, scale = True )

minX = min( [vertex.co[0] for vertex in obj.data.vertices] )
minY = min( [vertex.co[1] for vertex in obj.data.vertices] )
minZ = min( [vertex.co[2] for vertex in obj.data.vertices] )

vMin = Vector( [minX, minY, minZ] )

maxDim = max(obj.dimensions)

if maxDim != 0:
    for v in obj.data.vertices:
        v.co -= vMin #Set all coordinates start from (0, 0, 0)
        v.co /= maxDim #Set all coordinates between 0 and 1
else:
    for v in obj.data.vertices:
        v.co -= vMin


Camera view does not show any object I have a strange effect with one blend file.
When I switch from the viewport view to camera view the camera does not see the object, although it is in the view. There rendered image shows the object again.
To test this effect I deleted all objects but one.
This is the scene:

This is what the camera view shows:

This is the final render:

The test file (1 MB) can be downloaded here.

In camera view press Home key on keyboard.
Keyboards without Home key can press fn+←.
This is a shortcut for command Frame Camera Bounds and can be found from View menu under Cameras.


Why can I not select any vertices at all? I have been trying to select any vertices, faces or edges. It refuses to select anything.

I have selected the required selection on the bottom of the screen for vertex selection still it refuses to let me do it.
All my settings are defaults. I am stuck, no matter what I do!

I clicked LMB, RMB, even clicked down on my scroll, No success.

Why can I not select any vertices?

This is weird. Check the following:

The selected Object is a Mesh (not a Lamp, Camera, Empty or other form of weirdom).
You are in Edit Mode. To check this, look at the lower part of the 3D-View for selectable box with the text Edit Mode or Object Mode. If you hit Tab (with your cursor in the 3D-View proper), it should switch between Edit- and Object Mode.
Hit A to select / deselect all vertices.
IF no visible change happens, you are doing art. Else, it is the vertexial selection that fails.

Hope this helps.


How do you set the scale for a specific project? For my current project, I've decided to use metric units. I am trying to work at the millimeter level, but when I create a new object (Cube) it's set to a one meter scale by default. How do I tell Blender that I want the default scale for all new objects in this blend file to be set to, for instance, one centimeter?

When using the Blender units scale I didn't concern myself with this stuff, but I'm trying to be more accurate in my designs.

You can set units and scale in the Properties Panel

Newly added cube after scaling to .01m with Edge Info Length enabled:

There are also a few settings in 3D-Views Properties-Panel (N) these influence only the display:

See also:

How to model effectively using exact measurements?
How can I use imperial units when entering measurements?


Substracting many objects from a single object I am trying to recreate this wall with somewhat complicated indentations. I figured out the math and it's 8.75m wide, and it has 17 diviosions horizontally. I made a 17x5 grid of the "empty" that would be needed to be "removed" from the wall, to go from a parallelepiped to the wall full of holes. However, I'm not sure how to actually make the cut. I tried boolean substraction, but I can't seem to get it to work, it looks like it can only be done on two objects at once, but  I'm not sure how to join them all. I assume boolean addition might work one by one, but there must be a faster way
[

After you've created all the objects you want to "remove" from the wall, Join them. (Control + J in Blender 2.79).  Then you only have two objects, and you can do the Boolean subtraction operation.


Joining two windows doesn't work I click join area and then the Area Options dialog disappears and nothing happens.

quoting from the manual:

  order to merge two window frames, they must be the same dimension in the direction you wish to merge. For example, if you want to combine two window frames that are side-by-side, they must be the same height. If the one on the left is not the same as the one on the right, you will not be able to combine them horizontally. This is so that the combined window space results in a rectangle. The same rule holds for joining two window frames that are stacked on top of one another; they must both have the same width. If the one above is split vertically, you must first merge those two, and then join the bottom one up to the upper one.

read:
https://www.blender.org/manual/getting_started/basics/interface/window_system/arranging_frames.html?highlight=join%20window


Video Editor Text - Font Style Won't Change I am using the Video Editor and have added a new Text object to the sequencer at the bottom. When I try to change the font style using the "Strip" menu to the right, selecting a new font style does not change the way the font is presented in the preview. Clicking the "F" button next to the Font style, I see a "0" next to the fonts I've tried. Can someone explain how I can get Blender to recognize different fonts besides the default? Thank you!

I observed this behavior on Linux with Blender 2.83.5.
I found a workaround:

Create a font strip in VSE
Set the font you would like to use (the preview does not reflect this)
Delete the strip
Perform an undo. At least in my configuration, the text is rendered in the correct font.


How to lose colour on distant objects? I need achieve the following effect that can be observed in the image. Is it possible?

There are a few ways to make the objects fade in the distance like the image you show.

The most realistic would be replicating what would happen in real life: Suspended particles (haze, smoke or dust) would float in the atmosphere limiting visibility of objects in the distance.

To do that in Cycles you can add volume scattering and volume absorption shaders to the world's volume.

Click on the image to enlarge
A different way to do something similar would be to use a mist pass.

The mist pass can be enabled on the scene section of the properties panel

It creates a black and white image that gets progressively whiter in the distance.

It has a start and depth settings, that can be set on the world section. Objects that are closer to the start distance will be fully black, and those past the maximum distance will be fully white.

The the range from start to end can be visualized as a line, by enabling Display>Mist on the camera settings.

The Mist pass has to be composited into the rendered image using the compositor. Usually you want to Add the mist pass on to the image pass. The Factor on the color mix node will determine how much of the mist pass will be added to the image.

A different way to use the mist pass would be to use it to control the color on the image:

Lastly a different approach would be to use a normalized Z pass.

The Z pass represents the distance from objects to the camera. The limits are controlled by the clip distances on the camera.

Note that the Z pass, being a representation of distance will likely exceed the limits of the 0-1 range of what can be displayed as an image (0 being black, 1 being white), so normalizing the Z pass will convert those values to something that can be visualized.

The main disadvantage of this approach is that the Z pass is not antialiased, so your image might look blocky or pixelated on curves or diagonal edges.

For Additional info on the difference between mist and Z pass read: Difference between a mist pass and a normalized z-buffer?


How to adjust how a mesh looks in-between shape keys? I'm just learning about shape keys. I created two shape keys, the basis one and one with the tip of the finger bent. I added the bone of the tip of the finger as a driver. It works but, the changes I made so that the bent finger looks better make it so that when it's going back to its original shape it doesn't look quite right. How can I edit the in-between shape?

Shapekeys are not a very solid alternative to rigging. The way shapekeys work is by exclusively translating each vertex from the Basis to the shapekey. The shortest way to do this would be by translating each vertex in the way you see in your "in-between". Shapekeys should only be used for things such as facial expressions, correcting armature deforms, etc.  In short, the inbetweens cannot be controlled, you're going to have to rig that finger if you want it to move correctly


Where is the operator panel in Blender 2.8? The tutorial I read is based on 2.79. So I'm not sure if it's still the same name in 2.8. But I can't find anything providing similar functionalities.

It can be found in the 3d Viewport:

As well as in the Edit menu where it is called Adjust Last Operation now, where you can also right click it and choose Assign Shortcut if you wanted to be able to call it with a keyboard shortcut like it was with F6 in previous versions:

Obviously, it does not need to be F6 and could be anything that is convenient to you.


Blender constraint, parent issue I'm new to blender it's really amazing. I'm animating some mechanical engineering parts.

I want to create a small 2 finger gripper with a transform constraint so that when i move 1 object the other one follows.

Everything works fine if both objects do not have a parent, but if they have a parent it gets messed up. I want to add them to a parent because afterwards they need to follow the parent rot, trans, scale...

I've provided a small example gif to check.

Can anyone point me in the right direction how to achieve this ?

https://imgur.com/a/ONk6tPr

Cheers,

Max

thank you so much for the answers. Meanwhile I was able to come up with another solution,
but still thank you for the responses.

My solution was following.

Create your base node
Create an object which should move to the center of the base node
Create a line curve, for example Vector X+ (1,0,0), I used a small phython addon for that
Use a locked track constraint on the object and as source the line curve. Direction should be X
Assign the object as a child of the line
Now you select the line & object and create a duplicate, rotated by the Z axis. I used 3 objects so it was 120°
Delete the constraints of both objects, and create a new constraint copy location of the first created object. Use the local coordinate system on both values.
Assign all moveable objects as child nodes of the base node.

Now it should work as expected. You can lock the obejcts position and only X should be active in the main moveable object.

I added an arrow to limit the X axis movement and use this as a copy location source for the main moveable object.

Thank you again for the responses. Really appreciated!

Max


How to not display surplus texture (UV mapping) I am a very beginner modeling. I am struggling to make UV editor and now trying this one :

Question is how to display only part of eye. When I try to project eye on object, it return surplus part as well. How can I make like this ?

What I did on process is that (1)separate eye part from main object (2)add image texture (3)smart UV project. I would appreciate if it is explained in detail. Thank you.

You have the correct node setup for the material, but the image you are using needs to be alpha masked.

That is to say, you would need to take the image into (for example) Photoshop, and "cut out" the eyeball so that it sits on a transparent background. You would then need to save this a file format that allows transparency (e.g. .PNG).

This isn't working because, at the moment, your eyeball sits on a black background. Your nodes tell Blender only to show the image when it has alpha (i.e. only show it where it is not transparent). This is correct, but the problem is that your image is not transparent anywhere, so all of it shows.


Texture for 3D models are transparent at places I am using Blender 2.83 as a part of my Masters project. I have obtained 3D models of various fishes (.obj files), and I import them using
File > Import > Wavefront (.obj)
The models loads without errors, but the textures are "corrupted". I would appreciate any help and/or pointers on how to fix this. You can see images below. The "dark spots" are transparent spots

Some (maybe all) of the models are obtained from sketchfab, which have 3D previews where the textures look correct. The fish "groups" are the models viewed from left and right.
Beneath you can see a closer look of a model as well as the UV-editor view in case that is relevant.

This is cause by your material's blend mode.
You have 2 options:

In Material settings uncheck Show Backface
Change Blend mode to Opaque (this will fully disable transparency)


Flip normals on Metaballs? I would like to use metaballs for interior design (cave) via backface culling.
Is there a way to flip their normals? :p

Why not simply toggle off viewport backface culling?

Under the Properties Area (N Key) Shading > Backface Culling


Did my file get damaged when blender crashed? I was working on file that has a particle system ( fluid with a lot of options in physics ) which made blender kind of slow. Then I undid a step and suddenly blender shut down .
I tried to open the file again but blender kept shutting down before opened it. I checked other files in blender and they worked fine, except for that one which blender shut down. I dont know what happened. Does that mean that the file has been damaged? Knowing that the files size is just 12.8 mb
I use blender 2.78

I haven't seen files getting corrupted this way yet, and I've had a couple of crashes in similar situations, trying to bake particles included. Blender is very good in informing you it can't open something, it usually spits an error saying it can't open a file for X reason. Since you're crashing I'm more inclined to think your computer isn't powerful enough to deal with this file.

I suggest you to:

Before anything make a copy of that file, just for good measure.
Look for a blend1 file in the same folder and see if this one opens.
If not rename the cache_fluid folder used for this simulation (or the sim files themselves) then try to open the original file.
If you fail you can create a new file and try to append the crashing one to see what happens. Append to whole scene, or just parts if the rest doesn't matter.
If it isn't under NDA you may ask someone with a more powerful build to try to open your file. They may split the file in smaller files for you, or disable the simulation so you computer can work on it again. If you don't know anyone directly you can upload it and share the link here.
Alternatively you can try the methods listed here (https://www.reddit.com/r/blender/comments/4x8o0w/method_to_recover_corrupted_blend_files/).


Extrude is not behaving as expected I'm trying to extrude a section, almost like I'm scaling it, but the scaling doesn't seem to be working either. I can't find anything on why this is happening. It was working fine and then halfway through my project it isn't working!

The bottom picture is a screenshot of the tutorial I'm following along with. This is my goal. The top picture is of my project. Extrude pretty much just moves the selection along a dark blue axis. I've tried scaling, even by selecting S > Shift+Z, I've tried every extrude option (region, region normals, and individual faces) and I don't understand!

There are a few ways to shrink/fatten a region of an extrusion.. I don't know if this one is exactly in line with your tutorial....

E Extrude the end of the rod to the desired length of the region to be scaled
Now you have a set of faces whose normals you can extrude along ...  Alt select that face ring
Alt E > (Region, Vertex Normals) extrude the
face selection along its faces' normals.

Now, if you have the Transform Orientation set to 'Normal', you can select the faces at either end of the fattened section, and GZZ to adjust its ends.


Separate preview/render border settings possible? I like to render using the cycles in the viewport. To speed things up I use the render border (Ctrl+B) to mark a small region of interest. However when actually render (F12) the border is still there. I know that I can uncheck the box for border before I render. But is there a way to have the viewport use the render and when I go to main render it render the full resolution?

No. However, as of blender 2.65 you can use Render Border (CtrlB) while not in the Camera view, which will only affect the viewport:


Creating a curved rectangle on outside of a sphere? I'm having trouble finding a way to create a rectangular mesh that sits on the outside of a sphere (but takes the shape of the sphere).

Can someone lead me in the right direction?

It sounds like you want to do something like this:

To model that:

Add a plane (ShiftA > Add > Mesh > Plane).

Give it some extra geometry with a Simple Subdivision surface modifier:

Add a shrink wrap modifier and select the target object in the Target input box:

Add a Solidify modifier to give it some thickness:

And you get:


Black and white gradient on surface, where is my red color I'm following the sociamix tutorial and, in the 15 episode, the red color does not apply on my texture. I don't know why I get a black and white gradient only.
The tutorial
You can see the result at 19'

And here my result :

We have created a group to make it easier to manipulate the material.
My file
Thanks for your help

I'm not sure a factor output should even be able to show red the way he has it set up in that video, or it is possible that this behavior has changed since January.  In one of the next steps he disconnects this factor output and makes a new color output into a Principled shader, so I would just skip ahead to that part, I think.


How can I lock transformation of an object's vertices, edges, and faces? Let's say I have two separate cubes in the same scene. I want to adjust the mesh of one cube without risking unintentional alterations to the other. In 3dsmax, I remember there being a freeze modifier that kept an object visible, but you couldn't select any of it's vertices, edges, or faces. I'm looking for something similar to it in Blender.

In Blender, you don't need such a feature (not for preventing the edition of other objects, anyway) since Blender works in a different way. As I understand it, in 3DS Max you can select any vertex from any object at any time (unless, of course you freeze it, as you mention); however, in Blender, the procedure is to select an object and then go into Edit mode (Tab) on that object, which prevents you from editing other objects until you go back to Object mode (again, Tab).

As in this case it seems you created the second "object" while in Edit mode (which makes it a mesh, not an object), you can mouse over it and press L to it (actually, connected vertices) and P to make it into it's own object.


Help with combining objects So for this particular project, I need the object to be 1 but the animation to not move the actual machine. When I combine them together in the way I know how to it does this https://gyazo.com/fde11d1cecff66a43fb5b2d403f3a755

In your case, I think you want to parent the smaller objects to the main objects.  This would be done by shift-selecting the smaller objects then finally selecting the larger object.  Finally, press Ctrl-P and select Object.  The objects with the red-orange outline will be parented to the object with the orange outline.  This means that their movement is now relative to their parent object.  You can find documentation of this behavior here in the blender manual.


I bought a model on fiverr in .obj but it was sent as .txt Does anybody know how to make this into an obj file? Am I just stupid?

OBJ is basically a text file. It should be fine if you renamed the file and changed the extention from .txt to .obj.


How to build Blender as Python module? I'm on a Linux Ubuntu 18.04.1 LTS System.

As the title states I was unable to find any precise documentation how to build blender as Python Module for uses in scripts.

If anyone can help me I'd really appreciate it.

Thanks in advance.

Ok, i managed to actually build it as a Python module.
It might appear strange to ask a question and immediately answer it. But i decided to
share my experience with this process.

In this way it could help someone in the future who struggled the same way as i did.

Now to the process of the solution.

Starting point were the following three sources as follows :

This Question
An Archived Blender Wiki entry
The offical "Build from source" Wiki article

How did i achieve the build ?

I started by following the description provided of the 2. Source; which wasn't really precise in how to handle the source and so on and did not work for me in the end.

After a few failures of this, i went on by just following the 3. Source.

So i did what was stated there :

mkdir ~/blender-git
cd ~/blender-git
git clone https://git.blender.org/blender.git
cd blender
git submodule update --init --recursive
git submodule foreach git checkout master
git submodule foreach git pull --rebase origin master

Afterwards :

cd ~/blender-git
./blender/build_files/build_environment/install_deps.sh

Now I had every bit of blender code and all dependencies installed. Since i did not want blender compiled with UI (as normal programm) i was curious what (described in the next step, step 3, in Source 3.) make in ~/blender-git/blender offered.
So i proceeded with simply calling make help which gave the following (truncated for brevity) output :

Convenience targets provided for building blender, (multiple at once can be used)
* debug     - build a debug binary
* full      - enable all supported dependencies & options
* lite      - disable non essential features for a smaller binary and faster build
* headless  - build without an interface (renderfarm or server automation)
* cycles    - build Cycles standalone only, without Blender
* bpy       - build as a python module which can be loaded from python directly
* deps      - build library dependencies (intended only for platform maintainers)

* config    - run cmake configuration tool to set build options

Note, passing the argument 'BUILD_DIR=path' when calling make will override the
default build dir.
Note, passing the argument 'BUILD_CMAKE_ARGS=args' lets you add cmake arguments.

"Oh Hey, look what we got!" There it was, a make bpy which promised to solve all my problems.

So i executed it and it compiled. But I ended up with the Python module in a, at least for my desires, wrong directory : /usr/local/PYTHON_SITE_PACKAGES-NOTFOUND. I wondered how this happend.

I soon figured out that I had to reconfigure cmake in the new created ~/blender-git/linux_build_bpy via ccmake linux_build_bpy while in ~/blender-git. There i needed to enable the Advanced Settings via pressing t and then editing the Key PYTHON_SITE_PACKAGES from PYTHON_SITE_PACKAGES-NOTFOUND to my desired Path /usr/lib/python3.6/site-packages.

After changing this i had to rebuild the project, which didn't actually rebuild since the changed setting didn't affect the main build process.

Rebuild in ~/blender-git/blender via make bpy.

In the End I also deleted the stuff in /usr/local/PYTHON_SITE_PACKAGES-NOTFOUND.
(Ofc i could've just moved/copied it...)

That's how it worked form me. I hope this is helpful in any kind for anyone in the future.

NOTES:

make bpy might need superuser-rights so do a sudo make bpy and don't worry
about a complete rebuild (it's allready done just linking/copying in the end needs
those rights).
The configuration after the first build might not be needed or can be done before
hand, but i didn't figure out how to do so.
If followed through these steps, and the Python module (strangely a directory
called 2.80 or simmilar number) exists in the desired path but yet you are not able to import the module bpy in any of your scripts, make sure that your desired path is included in your PYTHONPATH Env-variable.


Texture on the wrong side of eyes after import from MakeHuman I imported this model from MakeHuman, by exporting it as a dae and importing it into blender. This worked great, however there is one "glaring" (pardon the pun) problem. The model's eyes don't have any texture, as can be seen here:

However, if I remove the eyes from the head and look inside them on the other side of the object, there's the texture!

I've tried flipping normals (by hitting space and typing flip normal and hitting enter) and recalculating them (by following the instructions here: How to recalculate normals?).

Neither of these results in the eye textures being on the proper side. It looks proper in MakeHuman

If you look closely, you will see two layers in the eye. The exported MakeHuman model contains the cornea of the eye as well (the clear layer that covers the eye). In the viewport this appears white, but when rendering it should appear mostly transparent.


Camera background image not visible through transparent cloth I have a simple cloth simulation that I want to export as a video.
A background image is setup from within the camera.
The problem is:
The flag is suppossed to be slighty translusent but the background image will not be visible through the translucent object the area will become more and more gray the higher the translucency.
I am useing Eevee and Alpha Blend, changing the blending mode does not work as Opaque causes artifacts witht he shadows and stay completely opaque until turning Fac up to 1.0.
Alpha Clip will keep the image completely opaque until Fac is at 0.5 then it will becom 100% translucent.
Alpha Hash does make the flag translucent and the background image visible but gives a very grainy low quality cloth.

Here is the problem with Fac at 1.0 to highlight the issue:

Turns out this is simply a viewport issue in the rendering its perfectly translucent with the image visible.


How to animate a propeller on the axis of rotation? I want to animate this propeller spinning in Blender 2.8. I have oriented the local axis of rotation as described here.

Here are the reference images at a larger size

It appears to rotate correctly here

Then I keyframe the rotation

The resulting playback is a very chaotic rotation on a different axis

Any clarity on what I am not understanding about this process is greatly appreciated. Thanks.

Rotation at odd angle -

Whilst I concur with the comments above, I remember doing this at some previous time.

The cube, shaft and 'propeller' here were added at the default location 0,0,0 and at the default straight  x,y,z  angle.   I'm not sure this matters.

The shaft and 'prop' were parented to the cube.

To experiment, the cube was then rotated at around 45 degrees in all 3 axis'.

-=============-

WARNING - Do not use CTL-A (apply) on any of the 3 components.

And for info - Keyframing as mentioned below was always done by hovering the mouse in the locatio/rotation slots at right and pressing "i" .

-==============-

The "Orientation" menu at bottom of window was then switched to "Normal".

Fearing a manual entry in the prop's X axis would be applied globally, after keyframing a zero in it's X rotation slot at frame 1, I advanced the timeline cursor to frame 80 and rotated the prop several times with the keys RXX.  This was the (normals) axis that aligned with the shaft. The mouse was used to drag the actual rotate.  That was then keyframed and it worked fine.

I'm not sure if this rotation experiment was necessary but it did provide reassurance.

A more adventurous rotation was then manually entered into the prop's X rotation slot at right: -36000 at frame 80. (100 rotations over 80 frames)

When run the animation rotated correctly.

The cube's location and attitude were then changed and keyframed and everything still remained stable.  An animation speed of 120 fps was used to check this.

-==============-

To conclude and whilst not recommended, when necessary however it appears you can get away with perpendicular rotation at odd angles, in Vers 2.77a  at least.

The Blend file is available on request but the key to it's success is probably due more to the order and manner components are added, rotated, and keyframed.

There were no active modifiers or constraints used apart from parenting.

It shouldn't make any difference but the above was rendered with OpenGL.
Further, when CTL-A was used, everything went haywire.


How to change mirror part way through making object without changing object? I have used the mirror tool in the X and Y axes to create a cone-like surface that is symmetrical in both directions.

Now I want to modify this surface to add details to it that are only symmetrical along the X axis.

When I attempt to make the changes I want now, it mirrors onto all four faces of the shape. If I attempt to remove or change the mirror, it deletes the mirrored parts of the object, which I want to keep.

You have to apply the mirror modifier for the Y axis. To apply a modifier press the the apply button on the modifier. Then you can go back in to edit mode and your details will only be symmetrical along the X axis.


How to export several render outputs at once? I want to know if it´s currently possible in Blender 2.78c/higher to render an image and then get the imge itself as well as the AO pass as two output files (.png) without having to switch to the compositor, change the output node connection from "Image" to "AO" and rerender the whole thing?

For I need the AO as a seperate image, but don´t want to render everything twice... (2 hours each).

If there´s a simple method/script I don´t know about please let me know!
Thanks all of you beforehand.

I'm using this setup as addition to the normal path and filename for the composed image:


Remove grass texture Hi, can anyone tell me how to remove the grass from the mesh shown, it is linked by a texture file but I can't seem to get rid of it. Thanks Nicola

This is probably a particles system on your object.

Go to the particle panel here. Near the green arrow you can click on the "eye" icon (just hides the particles) or click on the minus sign (to delete the particles).

At the bottom, the texture you are (probably) talking about :

If you remove it, you model may be "full of grass".


How to select all marked 'seamed edges' I have a maze and I want to select all of the 'seamed edges'.Maybe there is an addon for this? Thanks in advance.

You can do this with "Select Similar".
Select one of your edges with a seam, then go Select > Select Similar > Seam, to quickly select all the edges with seams.


Hair not emerging from all vertices in vertex group I am new to blender (version 2.83.5), and I am trying to render a lattice of spheres of alternating colours. My plan was to do so by subdividing a rectangle into several smaller faces, defining two vertex groups corresponding to alternating vertices on the rectabgle, then adding hair particles which render as the sphere objects.
This seems to partially work but, strangely, not all vertices in the vertex group are generating spheres. I have the "Random Order" button unchecked, and the number of particles exceeds the total number of vertices in the mesh. The missing spheres are all concentrated in one region of the rectangle (see the attached image) and particles are missing from both vertex groups.
Any help with this would be greatly appreciated!
Will

I have solved the issue - I had placed a solidify modifier on the rectangle and it was conflicting with the hair somehow. Removing the modifier has fixed it.


How solve "AttributeError: 'NoneType' object has no attribute 'ui_type'"? in Jupyter notebook i have loaded bpy module :

import bpy

with no problem. But if i load the 3D view :

bpy.context.area.ui_type = 'VIEW_3D'

give me this error :

AttributeError: 'NoneType' object has no attribute 'ui_type'

How to solve this?

bpy as a python module is headless

There is no ui associated with bpy that is compiled as a python module. Objects like screen area and region are part of the UI which being non existent, are given the value None.


Why shrinkwrap not working on the mesh I have a mesh and a plane that i want to shrinkwrap on that mesh. When shrinkwrap added its not wrap in the shape model. To the side its cut shape and not fully covered. On the top some part it got shrink and some not. Any help or suggestion plz Thanks

Are you shrink-wrapping to a single object? You're only allowed a single target object in the shrink-wrap modifier. You can duplicate and merge your objects for the shrink-wrap process; that way, your original model state stays intact.

Also, if you are using other modifiers, play with the order of your modifiers by using the up and down arrow buttons in the modifier panel. I believe modifiers occur from the top down.

Lastly, the shrink-wrap modifier can only work with the geometry its given. subdividing your sheets will add more geometry and give you a more accurate wrap.

Hope this helps!

EDIT:
After downloading your file and applying the methods I described above in a few clicks, I achieved the result you were searching for. There was not enough geometry in the 'sheets'. Also take note of the offset value in the shrink-wrap modifier. see image below:


Motion Tracking: No Camera for Frame X I'm trying to track a relatively simple scene, and I keep running into weird problems.  I know that the scene is blurry and low quality with only imperfect trackers available, but I don't really care about getting the motion tracking perfect.  I just need a rough approximation as this will only consist of a few seconds in the rest of a project I'm working on, and visual effects isn't the main purpose of it.
Anyway, the animation starts at frame 90 and ends at frame 205, but Blender keeps insisting on solving the track from frame 89-253... and then failing at that due to not enough tracks or something.  I think part of the problem was that I accidentally tracked some of my tracks too far beyond the end of the animation (using Alt+Left Arrow).  Also, the entire video is much longer than the duration of the animation.  But I can't figure out how to get Blender to just track the frames I care about and not the entire animation where only a few trackers remain accidentally enabled.  Also, I can't figure out how to quickly disable the trackers after the end of the animation without manually disabling each one by hand each frame.
How can I get Blender to track only frames 90-205, or what's causing the following error?

Here's the Blender file and video: https://drive.google.com/drive/folders/1rtCEqRwtqzN0PqP68Zq1EJOrEjXoZ7ns?usp=sharing
EDIT
Checking the Solve -> Keyframe checkbox and/or setting Keyframe A and Keyframe B to the start and end of the clearest section of my footage doesn't help as I still get the same error with it seemingly trying to track points outside of the duration of the animation.  Again, all I want is for the tracking to only solve frames 90-205, which are the start and end frames in the timeline.  But the console keeps complaining that it doesn't have enough data to solve frames outside that range.
EDIT
I managed to get it working by trimming the video clip to only have the frames that I wanted to track and then retracked the scene.  However, I would still be interested in finding a solution that didn't require trimming the clip.

Enable the keyframe box, and then set the range of keyframes you want to use for solving in the boxes below (keyframe A and Keyframe B).

Blender will solve the frames it can solve, meaning the frames for which there is a reasonable amount of information to estimate placement in the 3d world (or a low error).  The slected range is used to determine the camera intrinsics and placement.  Blender will then try solve the whole shot as marked in the beginning and end frame of the scene, but using the information gathered in the marked section of the shot.
For more information on motion tracking read this post:
How can I get better results when doing camera motion tracking?


how to combine 2 or more textures in Cycles? 2.7xxx how to combine 2 or more textures to achieve this type of image in cycles

similar to splashing texture that as far as I remember is a texturing technique

You can combine textures using the MixRGB node(Add>Color>MixRGB in the Shader Editor):

Note that you can choose different blending types:

As you can see you can mix any textures - proceedural and image. You can mix more textures by simply adding more MixRGB nodes.

In order to mix two textures with a smooth gradient you can use a gradient texture as a factor for the mix node:

I am using a MixRB node in Multiply mode to multiply the texture coordinate vector(to scale it) by 2 to make the gradient smaller. MixRGB node is for work with color, however it does work with any numbers as well and multiply mode does what it says - multiplies the values and it even supports negative values despite the fact that colors cannot have negative values, so there is nothing wrong to use it for some math with vectors as well.


Need advices on the topology of this mesh how can I improve the topology of this mesh?

It's just an exercise to improve my topology management.

If your render is OK you can keep it as it is, there must be simpler topologies like this one:


Modular UV unwrapping and texturing curved areas So I'm trying to make these modular road tiles (5pcs) and decided to do a quick build to see how well everything fits and to test out some texturing. The end result is trying to become a bit stylized/cartoony feel.

I've now hit a tiny roadblock as the corner pieces are curved and not straight in the uv's. I can't seem to find a way to unwrap the model for the Light grey areas to be straight and use a single texture image for it.

The straighten uv button (or plugin, can't remember which ones those are) isn't really straightening anything but making the uv islands more crooked and not eliminating the curve completely.

Do I need to just bite the bullet and make separate textures for all curved areas or is there a way to unwrap the islands straight?

Any tips are welcome too. First time trying to do anything modular.

Thanks in advance.

Using blender 2.79b

Weeell, this isn't my place of expertise, but it'd suggest minding where you place your seams.

and yes, Separating the mesh into bits is also not entirely out of the question

From the looks of things you need to find some way to move the texture about. I suggest finding Darrin Lyle's UV mapping Tutorials on YouTube, they're invaluable for stuff like this. it looks cool too, lemme know when you've gotten around this.


Particle system not rendering in cycles I've been making a beauty and the beast animation for a school project. and I've created a particle system that sort of creates streaks coming from a single vertex however it will only show in 3D view solid mode. so it wont render in my final product could someone pls tell  me why? Sorry if it's obvious i am reasonably new to blender.

Cycles cannot directly render particles. You can select Object in the Render particle properties panel to render each particle as a duplicated object or you need to use a different method of generating geometry from the particles. One such solution to generate trails from particles is defined in How to add trailing light effect to finger tips?


Assign randomly a mesh to multiple faces Suppose that the first image may be a ground pile, and the second a simple little rock

Is there a way in blender that allows me to put the rock on the faces of the ground pile randomly?
In other words is there a process to duplicate and then assign randomly my rocks to the pile's faces?
My goal is to create a pile of rocks

Yes, you can do this with a particle system.

Create some different rocks.

Group the objects by selecting them in object mode and pressing ctrlG; their outlines should now turn green. This is not into the same as putting them in the same mesh. This will leave each object as it is, so each object can have different modifiers, meshes, materials, and all that. "Grouping" is just a way to tell Blender that these objects should all be treated in a certain way, like as the particles in a particle system... or other things. Once you group them, you can go to the object tab and you'll see a "group." An object can be a member of more than one group. If it is, you'll see multiple "group" panels there. To remove an object from a group, you'll just click the X on that panel, like you would with a modifier.

Add a particle system to the "pile." In the "render" section of the particle system select "group." Then choose the group that you put all your different rocks in.

This will randomly select rocks from that group and distribute them over the surface of the "pile." There are other settings for how to handle groups, but the defaults should work for your purpose.

Increase the "emission" value to make more rocks.


Combining two renders with different seeds So I've been dinking around with the NetRender function in Blender, using an addon I found to enable GPU NetRender functionality, I'm looking to render single images across multiple slaves

My first idea being to set a render border and send two jobs with different borders to two different machines, but the NetRender doesn't support Borders.

So I fell back on Image Stacking, rendering two shots with different seeds, but due to my idiocy, I can't find a way to merge two pictures of different sample seeds, I have both rendered shots, but can't for the life of me find a way to combine them, in Blender, or in my photo editor of choice, GIMP.

What would be the most optimal way to go about this?

You could try using or writing a program that calculates the average of the pixels and outputs to an image format.


I need a hint to model a modern heater radiator Doing it in edit mode, start with a plane and then extrude them at all, use booleans..., the main stopper are the curved blades and how to combine them with the central vertical pipe and the cilinders... the image shows two modules, I only need a half module (mirror modifier and array will do the rest) I apologize if i'm asking this in a wrong way.

Depending on the amount of detail you need, it is rather easy to model.
I made this in just a few minutes (took me longer to write this answer).

First break down the object, and think about each part.
There are nine fins (and it looks the same front and back), so use a plane Solidify, Array and Mirror modifiers to make those.

The bottom corner is beveled on all of them, so before applying the array modifier bevel the bottom vertex CtrlShiftB.

Add a plane as a separate object to use as the back.

Back in the original object, now with the mirror modifier applied, start editing the individual fins. Move the center three up. Extrude the bends for the inside ones, and extrude the outside frame.

Just add two cylinders, and bevel the remaining corners, and tweak the shape.

It really pretty easy. Use the modifiers! Solidify and Mirror are a must for this object.


In UV map can't move shared vertices independently After I unwrap my model, whether or not I set seams.  I can't move each vertex independently on the UV map.

I was able to on the first model, but now when I open that model, this no longer then case.

It seems to be that when I select a vertex, it selects the same vertex in another seam on the map.

How can I stop this.  Is there a separate or un sync option I'm missing for this?

This happens because you have the "Keep UV and edit mode mesh selection in sync" button enabled, the selected vertex in the UV editor, is on a seam, so in 3D view, it is shared by 4 faces - assuming you are working with quads- so when selected with the sync option enabled, it will select all related coordinates in the UV editor, disable it by clicking the button, in the image below, it's the button in the lower right corner.
As you can see, I have it enabled, here.

Now check the image below, I disabled the Sync button.

Hope this helps, happy blending.

Edit:

When you have the Sync button disabled, you can only see in the UV Editor, the faces that you have it selected in the 3D View in Edit Mode, so make sure you select all the faces you need to have it available before unchecking the Sync button, or use the 3D View to select the faces/edges/vertices you need, and tweak them in the UV Editor with the Sync button unchecked.


Trying to set a Keyframe in the Curve Data tab using Python I've been attempting to set a keyframe for the Bevel Factor Start and End of a Curve.

I've tried using

bpy.ops.anim.keyframe_insert_button(
        'Curve.bevel_factor_start',
         index=-1,
         frame=bpy.context.scene.frame_current,
         group="")

But I really don't know where to go from here. Pressing "I" works just fine but I can't find the right command in the API to control this property

While likely not optimized the following appears to work both in blender 2.79b official and the 2.80 beta build I have at the moment and may assist in how to handle adding the key frames and manipulating them afterwards.

import bpy

obj = bpy.context.active_object  # Your pre-existing selected curve

def add_keyframes(obj):
    if obj.data.bevel_object:  # verify bevel object already selected
        obj.data.keyframe_insert(
                "bevel_factor_start",
                index=-1,
#                frame=1,  # defaults to current frame
#                group=""
                )
        obj.data.keyframe_insert(
                "bevel_factor_end",
                index=-1,
#                frame=1,  # defaults to current frame
#                group=""
                )

add_keyframes(obj)

def mod_fcurve(obj, path):
    for fc in obj.data.animation_data.action.fcurves:
        if fc.data_path == path:
            my_fc = fc
    for pt in my_fc.keyframe_points:
        pt.co.x += 1  # increase x 'frame number' of points
        pt.co.y += 0.1  # increase y 'value' of all pts in curve

mod_fcurve(obj, "bevel_factor_start")


Best approach for a random terrain rolling ball animation? Simple question, just looking to be pointed in the right direction as I am somewhat new to things.
I'm creating an animation where a ball shaped robot (think BB8) has to roll around various terrains and scenes, in control.
I can model, texture, and keyframe just fine (though I am only just learning these things), but the best approach for the rolling ball is snagging my progress some. We will see the character close, so the contact with the ground and the rolling should be accurate as expected.
Simply keyframing the position and rotation seems impossible for this.
I know I can "draw" paths to follow, though this may not be practical in following the ground nicely, and there's the issue of making the ball roll.
I could  use physics to keep the ball grounded and have it roll, though there's the question of actually making it move where I want for the animation itself.
The terrain will be uneven and realistic, like a beach or rocks or forest.
Physics may be the best solution though I've looked and can't find a way to animate a physics object, specifically a sphere, moving around to specific areas. But maybe another approach is what I need! I could be missing something about paths.
Another detail is that the rolling part of the robot doesn't need to face any particular way, it just needs to roll.
Hopefully this leans more planning and effort in the setup and less in the actual animating, as there is obviously a lot more to think about than just getting a character moving to the place you want and rotating correctly.
Thanks for any help!

I would manage all your keyframes as you have been doing, set the ball to be a Rigid Object with Dynamic property, and the terrain to be a Rigid modifier, too - but the collision type set to mesh, and then bake it.
Once you've done that, you could then convert the bake to keyframes, and tweak it to your liking.


How to deselect non-manifold geometry? We can select non-manifold geometry by python function select_non_manifold() or Select Non Manifold command in editor. However, in my case I need to deselect non-manifold geometry. Is there a way to do this?

Let's have some selection, from which we want to deselect non-manifold geometry:

Invert selection CtrlI:

Select non-manifold ShiftCtrlAltM:

Invert selection CtrlI:

Tadaa!


How to attach colors (e.g., gradient color) to fluid particles This is follow up question based on {this post}, indeed.

The question is how to attach color attribute to fluid particles?

For example when a part of colored fluid (as explained {here}) separates, how to keep the assigned color moving with the particle?

For demonstration check the following:

The answer depends on how much control you want to have over the color. In Cycles you can use the Geometry node's Position output as a factor between two colors or two shaders, and this will give you a variation between them.

If you want control over the angle you can then route that Position output into a Normal node and connect the Dot output into the Factor of the two colors - rotate the sphere to change the angle.

If you want it to be driven by the distance from an Empty then look into Drivers.

And finally, as another possibility for coloring/texturing liquids you might look into how to create matcap materials in Cycles.


Random per island broken in 2.9? I am having an inconsistency between outcomes using the node Geometry>Random per Island
It is the same node setup behaving differently between 2.83 and 2.9
2.83: I will get the colors assigned to the color ramp distributed within the meshes that have that material. The limitation is the “island” meaning that closed meshes will have one color assigned.
2.9: Every different face of my mesh will get a different color from the color ramp. This is not what I need since I am trying to assign random colors to multiple assets, but each asset in itself can not have a different color per face…it looks really funky
Have you experimented this?

not sure if answering 9 months later is going to be helpful but I came across a similar problem yesterday. In my experience Random per Island works fine until you use autosmooth (Botom Row of the picture) thats when it gets funky, it also changes if you are using hard normals (first column of the picture) or smooth normals (second column).


Python - Changing scenes' header color gives fever to CPUs I have this script that changes the header color regarding the scene I am working in. The code is :

def header_color(self, context):
    global header_colors
    scene_name = bpy.context.screen.scene.name
    pref = bpy.context.user_preferences

    if scene_name == 'Editing table': pref.themes[0].info.space.header = header_colors[0]
    elif scene_name.startswith("Tag: "): pref.themes[0].info.space.header = header_colors[1]
    else: pref.themes[0].info.space.header = header_colors[2]

def register():
    bpy.types.INFO_HT_header.append(header_color)
def unregister():
    bpy.types.INFO_HT_header.remove(header_color)

This function is incredibly CPU consuming. If I replace the conditional sequence for a straight...

pref.themes[0].info.space.header = header_colors[2]

...the cpu activity is back to normal.

Do I do something wrong?

Why so CPU intensive?

Blender will call that function far more often than you think. Prove to yourself by adding a print statement in the function. that will explain the excessive CPU consumption.  It' s a neat idea but this is not the way to implement it. There are no events that fire off upon scene change, else that would be a great idea for an event handler.

One possible approach

I'm hoping this will anger someone else into giving a better answer :)
An alternative is to code a dedicated menu for switching scenes.. something like this.. (use better class names than these )

this gives a menu of scenes in the current blend
lets you pick one
switches color
switches scene

--

import bpy

class SimpleSceneOperator(bpy.types.Operator):
    """Tooltip"""
    bl_idname = "scene.select_and_color"
    bl_label = "Simple Select Scene and Color"

    scene_name = bpy.props.StringProperty()

    def execute(self, context):
        pref = context.user_preferences
        header_colors = [(1.0, 0.7, 0.7),(0.7, 1.0, 0.7),(0.7, 0.7, 1.0)]

        if self.scene_name == 'Editing table':
            col = 0
        elif self.scene_name.startswith("Tag: "):
            col = 1
        else:
            col = 2

        pref.themes[0].info.space.header = header_colors[col]
        context.window.screen.scene = bpy.data.scenes[self.scene_name]
        return {'FINISHED'}

class CustomMenu(bpy.types.Menu):
    bl_label = "Custom Menu"
    bl_idname = "OBJECT_MT_custom_menu"

    def draw(self, context):
        l = self.layout
        col = l.column()
        col.label(text="pick a scene")

        opname = "scene.select_and_color"

        for sc in bpy.data.scenes:
            col.operator(opname, text=sc.name).scene_name = sc.name

def draw_item(self, context):
    layout = self.layout
    layout.menu(CustomMenu.bl_idname)

def register():
    bpy.utils.register_class(SimpleSceneOperator)
    bpy.utils.register_class(CustomMenu)
    bpy.types.INFO_HT_header.append(draw_item)

def unregister():
    bpy.utils.unregister_class(CustomMenu)
    bpy.utils.unregister_class(SimpleSceneOperator)
    bpy.types.INFO_HT_header.remove(draw_item)

if __name__ == "__main__":
    register()

    # The menu can also be called from scripts
    # bpy.ops.wm.call_menu(name=CustomMenu.bl_idname)

could be triggered from 3dview, if you assign a shortcut to it, else the current code adds a menu item to the end of the info header, not ideal but gets the idea across.


How do I make objects ignore certain Light sources? I have a scene which has a spot light as the main light source. To get the scene as bright as I want, I have to set the value for the strength to be quite high, something like 5000. The problem is, some textures get too bright and start losing details.

My question is, is there any way, maybe through nodes, to make an object not being influenced by a certain light source?

Thanks in advance
- Marten

This isn't possible in Cycles just yet; You will need to move those objects to a different Render Layer. However it is possible on Blender Internal, using one of these methods:

Materials

By default, materials are lit by all lamps in all visible layers, but a material (and thus all objects using that material) can be limited to a single group of lamps. To enable this, navigate to the Material menu's Options panel and select a group of lamps in the Light Group field. Note that a light group must be created first.

If the Exclusive button is enabled, lights in the specified group will only affect objects with this material.

Render Layers

You can also use RenderLayers. If a light group name is selected in this Light field, the scene will be lit exclusively by lamps in the specified group.

Check the relevant wiki page.


2.8 Light Bleeding in EEVEE? I am modeling a quick interior scene in Eevee but I cannot seem to get past the light that appears to be bleeding through the small crevices of the cube and the randomly lit regions. I solidified it and selected ambient occlusion in an attempt to resolve this as some suggested, but it's just not working. What am I doing wrong here? Will you please help me resolve this?

Here is the blender file:
quick_interior.blend

EEVEE is not good at calculating shadow light path, since it's not ray tracing.

There is a contact shadow option in your light source setting:

It uses ray tracing to "fix" those bleeding area:

In game practice, light will not likely put outside the wall, and should use some light stop method to make it stay in specified area. Might use Cycles for those great lighting result.


Constant error message in console - reinstall and factory settings doesn't fix I am seeing an error message in my Blender console constantly. Not sure if it is affecting performance of Blender or if recent errors in the software have been for other reasons. I have no idea what any of it means but hoping someone here could give me some advice. I have tried a repair installation and reloading factory settings but doesn't stop the error from occurring, even when just doing simple operations in the default scene. I'm a bit concerned it might be a more serious problem with my computer which has crashed recently and I was forced to manually replace some dlls...

Traceback (most recent call last):
  File "C:\Program Files\Blender\blender-2.79-windows64\2.79\scripts\startup\RenderStreet\ui.py", line 130, in draw
  File "C:\Program Files\Blender\blender-2.79-rc1-windows64\2.79\scripts\startup\RenderStreet\settings.py", line 27, in __init__
  File "C:\Program Files\Blender\blender-2.79-rc1-windows64\2.79\scripts\startup\RenderStreet\settings.py", line 31, in ParseSettings
  File "C:\Program Files\Blender Foundation\Blender\2.79\python\lib\configparser.py", line 696, in read
    self._read(fp, filename)
  File "C:\Program Files\Blender Foundation\Blender\2.79\python\lib\configparser.py", line 1077, in _read
    raise MissingSectionHeaderError(fpname, lineno, line)
configparser.MissingSectionHeaderError: File contains no section headers.
file: 'C:\\Users\\JohnMcC/.renderst/RenderStreet.ini', line: 1
'\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00'

location: <unknown location>:-1

The problem is due to Render Street trying to read a configuration file. To remove the add-on completely (despite not showing up in User Preferences) remove the Render Street folder from within the (c:\program files\)Blender Foundation\Blender\(version)\scripts\startup directory.


Box Mapping on just X & Y Axis I'm box mapping a grunge map to add dirt to the bottom of some assets which works great....except it is projected on the z axis as too.
Is there a simple way toto just project on X & Y that I'm missing?

This is easier/smarter to do with a procedural texture for the dirt, but I got it to work.

I used Texture Coordinates>Normal>Separate RGB and plugged the Blue into a color ramp to get all the upward faces.
I mixed that using Mix RGB>Multiply with a Gradient Texture, rotated 90 degrees on the y axis.
Together, these make a top to bottom gradient mask that ignores only the very top upward faces.

Little more complicated that I wanted, but maybe useful for texture layering.


How can I improve the quality of a voronoi style mesh I have been trying a few method to try to create a voronoi style organic type mesh.
My current method is as follows

Create a shape

Cell fracture (using a partial system for good distribution)

Merge by distance (using the slider to remove verts which are too close)

Delete any edges which would cause too many elements

Apply modifier - Skin

Apply modifier - Subdivide

Apply modifier - Remesh

Apply modifier - subdivide

The result is sort of what I'm looking for, but I was hoping it would be smoother.
I have been trying to get working on this with sverchok (using the scipy module to use 3D voronoi, but I cant seem to get pip working to install it - I have another thread open about that as well). So currently this is my method.
Does anyone know of any other method for achieving similar result which are smoother final surface texture or product something similar with less steps in the workflow.
Having to go through a delete excess edges manually is not ideal.
Any suggesting would be greatly appreciated!
Thanks in advance!

Here is example of mesh voronoi, but we can handle surface and solid shape voronoi also.


Straightening Lines without Straightening Iron Thanks for looking this over in advance.
Hopefully pictures describe this somewhat well- but I'm looking to take the guess out of my guesswork here and have lines which are "perfectly straight". Here, that means for Vertex A, B, C all on the same plane and collectively forming an Edge, with Vertex B at some point between the two others- the interior/exterior angles at Point/Vertex B are equal to 180 degrees.
Any thoughts on how to go about doing this?
In case there's a mixup, the second picture is simulating what I want to do, but that's going about it in the eyeballing way/guessing where co-linearity occurs.
Additionally I should mention that similar questions suggest scaling on an axis around a median point, which works great for lines which are perceptively straight up/down or left/right, but with this angled business the method does not appear to work as described.

You can do this with a custom orientation.

Select the A and C vertices and choose a Normal Orientation
Click the + button to save this new orientation
Select vertices A + B + C (order matters) and set pivot point to Active element
Scale the selection to 0

Making a custom orientation

Scaling to 0, active vertex as pivot point.


Packing multiple objects for 3D Printing I am looking for an addon/script that packs multiple objects together to take as little scene space as possible, this is for 3D Printing services that charge per bounding box of all objects in a file (objects arranged as neatly as possible without too much empty space in between).

The feature is present in an expensive 3D Printing software called Magics.

I think there's not (yet) such addon, the only 3d printing related one (included by not enabled by default) has not this feature, but I guess it also depends on some printer spec, like the printing area shape, maybe other things, like the printer type (a powder sintering printer can print things in a very different way than a fdm printer, eg).

The only thing you can do now in Blender, if it helps you, is to use the UV map "pack island" tool to simulate the best layout from the objects you have in the scene, maybe.

If you can find out what is the shape for each object that has to fit (it could depend a alot on the objects shapes), you can create a plane for each object shaped like its limits.

Then merge those separate planes together, in a single object and then UV unwrap them. The UV/image has a "pack islands" that can optimize the UV maps on the texture space.

Here I did it with some basic shapes, just to get you the idea:

I just used the largest horizontal face for each separate mesh. I know it could not be realistic, is just to give you the idea.

If you can consider the texture space as your printer printing bed (ie: only square print beds), the UV can be optimized to fill it (you can also scale them).

then the "pack islands" could help you to find the best way to pack them in that space. eg going from

to

then, of course you have to replicate that layout in the 3d view to get the same suggested placement. If this helps you you can also export the uw layout as .svg and then import tht svg into blender, to help you as a reference (eg: snapping)


Is there a "thickness" node? I'm looking for a node that will return a white value for the thickest part of an object (as seen from the camera), fading off to black as the thickness becomes 0. Does such a thing exist?

I'd like to simulate an opaque light without needing caustics, so my idea is that center of the object would be the brightest part with the outer edge being darker.

Is Vector Math set to Length close to what you need?
You can invert it (or not) with a Map Range node, and then the From Max parameter becomes a slider for you to control where the effect terminates.

Something I cooked up using this:


How to model a twisted cylinder like this I'm new to modeling. I want to make a cylinder-shape object as follow. I'm thinking of it as a twisted cylinder.

I tried using twist modifier on a cylinder but the result was disapointing.

How should I make them? I'm using Blender 2.8

I would use the Screw modifier for both examples, assigned to simple profile meshes.

Because the longitudinal connections are staggered, this method avoids the creation of twisted, non-planar faces.


What is the right way to apply an image texture over a glass or plastic material? I am trying to put a label over the transparent plastic bottle, but i was unable to do so, because when i build the bottle material(plastic) and mix it with the diffuse shader(using the label texture), the label gets faded. So the solution i found was to duplicate the bottle and scale a little bit and apply the label material on it. So it looks its the same material, but in reality its one material over the other. How can I make my plastic material be under my label material(image)? Here's how it looks:

Here's my material setting for the plastic bottle:

Thanks in advance.

To begin with, the add shader node can only be used to add shader/closure outputs (green sockets).

With invalid input, the output of the add shader node will always be 0.
To add values (grey sockets), use a Math node (ShiftA> Converter > Math) instead.

Note that plastics do refract light, so a glass node will probably do just fine for the plastic material (if you were using the transparent node to reduce noise/render time, you might be better off with the fake glass setup).

As for mixing, you need to use a black and white stencil (in this case the alpha channel is perfect, but this will not always be the case) as the mix factor (I multiplied it with the output of this node group to remove the tiled repetitions of the image):

Here is the node setup (click for higher resolution):

And the result:


Efficient tool for making tree-like shapes DISCLAIMER: I am quite new, so this might seem like a stupid question.

PROBLEM: I'm trying to model this tree I found some pictures off.
I'm doing the branches like this but it is quite tedious. (I can't insert a video?)
Basically making a cylinder, loop cutting it, and dragging, resizing, rotating, them to fit over the reference image.
Here is pictures of process:

QUESTION: Is there a more efficient way of doing this? A tool I can use that bends meshes easier without having to mess with the vertices in edit mode?

Skin Modifier

add a new mesh object, go to edit mode, delete all vertices
add Skin modifier
in edit mode with Ctrl mouse click create a new vertex
now you can start draw branch by another click with Ctrl or press E (extrude)
change thickness of vertex by cmd+A on mac (Ctrl+A on pc?)

Notes: you can change size (thickness) also

from 3Dview > Properties panel (N) > Vertex Data > Radius X/Y
or check or reasign shortcut in User Pref >  Keymap > search Skin Resize

Grease Pencil

You can use Annotation or Grease Pencil object to draw branch and convert to mesh and use Skin modifier. But it is probably more work. Like with Annotate tool ** you will have to Convert to GP, than Convert GP to Curve, than Convert to Mesh. Using default Annotate tool generates smooth but vertex intensive line that doesn't fits to Skin modifier later (you would have to use Simplify add-on in step Convert GP to Curve ...


How can I read data from an Arduino without resetting it? I would like to read the data printed by an Arduino in Blender but the Arduino is reset each time Blender reads the data.
Here is my Blender code:

import bge
import mathutils
import serial

from math import pi
def Player():
cont = bge.logic.getCurrentController()
obj = cont.owner

serialport = serial.Serial('COM3', 115200)

# tell Arduino to send values
serialport.write('a'.encode('ascii'))

# read a line from the serial port
line=serialport.readline()

# Pi radians = 180 degrees so, since Arduino sends values between 0 and
# 255, we devide by 255 in order to spread the 255 over pi radians (from
# -90 to +90 degrees).

# There is one angle for each axis, and there are 3 axes.
Angles=[0.0,0.0,0.0]  # inicial angles for X, Y and Z axes
AnglesNumber=3       # number/quantity of angles/axes
for i in range(AnglesNumber):
     Angles[i] = Angles[i] + (float)(line.split()[i])
     # And we convert each value to radians (from -pi/2 to +pi/2).

mat_rot_z = mathutils.Matrix.Rotation(Angles[0], 3, 'X')
mat_rot_x = mathutils.Matrix.Rotation(Angles[1], 3, 'Y')
mat_rot_y = mathutils.Matrix.Rotation(Angles[2], 3, 'Z')

obj.localOrientation = mat_rot_x * mat_rot_y * mat_rot_z

You create a new Serial each time you call that script.

It is better to create it once and communicate with the connection as long as it is established.

Unfortunately I can't provide you with working code due to non-existence environment.

Connecting

One script gets executed and establishes the connection once:

serial = serial.Serial('COM3', 115200)
owner["serial"] = serial

Communicating

A second script handles communication (polls for data) running at each single frame.

serial = owner["serial"]
serial.write('a'.encode('ascii'))
line = serial.readline()
...

Combined

Due to the strong dependency between connecting and communicating, you might want to combine both operations:

serial = owner.get("serial");
if not serial:
    serial = serial.Serial('COM3', 115200)
    owner["serial"] = serial

serial.write('a'.encode('ascii'))
line = serial.readline()
...


Object rotates on a different axis I recently made a Knife. I got stuck. Whenever I try to rotate that knife along Y axis through transformation panel, it get rotated along X axis. Same when doing along X axis,it rotate along z axis. But Z-axis rotation is fine. I ensured XYZ
euler. Tried Global to Local. Need Helpp..

You Can Use The Hotkey Instead Of the transformation panel Which Is (R) Button In The Keyboard To Rotate ,And Choose On Your Keyboard The Axis You Want To Rotate Around (X) or (Y) and (Z)
And Type Your Rotation Angle Or Move Your Mouse.


Can I use images rendered with blender for commercial use? If I make a scene and then render it with BR or Cycles, am I allowed to use that image in a commercial project? Do I need to include any copyright notice or license?

Short answer Yes.
Just as you own what you draw with a pencil, you own works you make with Blender(no difference).
To quote from blender.org

Your artwork
What you create with Blender is your sole property. All your artwork – images or movie files – including the .blend files and other data files Blender can write, is free for you to use as you like.
That means that Blender can be used commercially by artists, by studios to make animation films or vfx, by game artists to work on commercial games, by scientists for research, and by students in educational institutions.
Blender’s GNU GPL license guarantees you this freedom. Nobody is ever permitted to take it away, in contrast to trial or “educational” versions of commercial software that will forbid your work in commercial situations.

Meaning anything you make in Blender (images, scripts, add-ons, models, entire scenes, materials, textures, and so on) is yours, and you can do anything with it, without any legal notices at all.

A general note about Open-Source, not specific to Blender.
You don't have to get into details of each license.
Any OSI approved License assured you can do what you like with works created from OpenSource software. This is part of the Open-Source, definition as defined by the OSI,
http://opensource.org/osd
Points 5 and 6.

No Discrimination Against Persons or Groups

The license must not discriminate against any person or group of persons.

No Discrimination Against Fields of Endeavor

The license must not restrict anyone from making use of the program in a specific field of endeavor. For example, it may not restrict the program from being used in a business, or from being used for genetic research.


How to only texture paint one side of mesh? I created a model of a mask by modifying a cube. (So it is not a plane.)

It's basically half of an ellipsoid. I did some texture painting. The texture shows up on the front of the mask as well as the back. I do not want it to show up on the back. How do I remove it?

this is a go around that I just found.
For that you need to modify your material so it applies one different shader on each side of your faces.
So here is the mesh, the top half show back of the faces and the bottom half show the front of the faces.

And here is the material I used.

The trick is done by the geometry node setting the Backfacing attribute as factor for the two shaders.

So I hope it helps.


Cycles Render bake over texture with transparency I'm somewhat new to Blender so please keep that in mind when providing any answers as I'll probably even need directions to where I could find various settings or menu items. I'm using Cycles Render and I have a really simple scene setup. I have a plane, a cube, a light and a camera. The plane is using a PNG texture that has some transparency to it on the sides. You can see a screenshot of everything bellow:

What I'm trying to achieve is to bake the shadow the cube is creating on my plane into the plane's texture. The way that I've tried it is the following: I first make sure I have my Image Texture selected inside the node editor and then I press the Bake button. The result can be seen bellow:

As you can see the shadow from the cube does appear properly however the transparency the texture used to have on the sides is replaced with a darker gray. How can I avoid this? I would like to keep the areas with the transparency my original texture had and simply just add the shadow on top of it WITHOUT loosing the transparency.

Thanks so much in advance!

I ended up finding a way around this. Basically I would bake only my shadows to a separate image and then manually add them to my textures with Photoshop. It requires the extra step, but I ended up liking it even more this way because I can adjust the shadows some more.


Can you use Open Image Denoise on the gpu in blender 2.91 or will it only work on the cpu? Can you use Open Image Denoise on the gpu in blender 2.91 or will it only work on the cpu? And if you can do it on the gpu, how?

Seems like it is made for CPUs: https://www.openimagedenoise.org/ so it does not work on GPUs. It's created by a CPU manufacturer after all. We have OptiX denoiser for GPUs.


Short animated film in Blender in single room environment with several acts - single scene or multiple scene setup? I'm animating a short animated film that takes place in a single room.
There are 3 acts, with multiple characters, with the room in different states between each act (objects moved/added/removed, different characters, different lighting, camera positions, etc).

I've finished the first act. For consistency I started the second act in the same scene instance... however, it immediately became apparent that this would be an absolute mess in the NLA and Dope Sheet, not to mention all the different camera setups, follow paths + constraints, etc. still visible from the first scene.
It felt completely wrong.

So then I tried starting a new scene based upon my single scene with bpy.ops.scene.new(type='LINK_OBJECTS'), but  all the object animation data was still linked, which didn't help matters regarding the cluttered dopesheet/NLA problem.

Alternatively, using bpy.ops.scene.new(type='LINK_OBJECT_DATA') is also very problematic. It creates duplicate objects, while object animation data are no longer linked between scenes (good), object properties, transforms, collections and hierarchies aren't linked (bad).
And While I want some object data linked across multiple scenes (eg, materials & armatures), I don't want shader tree and armature pose animations to be linked (for obvious reasons).

And if I want to change/add/remove anything to the room (besides object-data like materials which remain consistent) it requires going into each scene and making the same changes repeatedly.

It feels like there's something I'm failing to notice, because all of this feels very very wrong.

I'm guessing most lengthy & complex blender animations are sequenced together from multiple blend files / scenes, and the issue of duplication / loss of consistency is something we just have to live with.

Any helpful advice / ideas to get round these issues?

Just go and keyframe the environment how you want it then delete all keyframes before that point move those keyframes to the first frame and go from there. (this is just a suggestion.)

make sure it's in a copy of the scene btw because you wouldn't want to lose that progress


UV Mapping a modified Cylinder Create a cylinder with NoCaps.

In the Top View, select all faces, Mesh -> Extrude -> Extrude Faces Along Normals

to get a shape like so:

Applied all Transformations in Object mode CtrlA -> All Transformations

Apply a checkered map like so:

To fix the shown parts and others, added Seams like so:

Select all faces UV -> Unwrap

The distortion is still the same.
Tried with other seams and changing Unwrap from Angle to Conformal with no affect.

Any clues on how to go about fixing this?

Appreciate any help.

Thanks & Regards.

By default your material uses auto generated UVs. To use your manually created UVs you must change the input vector to UV map instead of Generated.


Spin Tool Cursor Not Showing/Snapping to 3D cursor I am trying to use the spin tool on my mesh but the tool is not appearing in my window. I have the cursor snapped to the face of the object itself but I do not see the spin tool when I have it turned on. I have modeled other meshes with the spin tool within the same blend file without issue, it just suddenly stopped showing up when I wanted to use it on this mesh and subsequent meshes. Even when zoomed out I do not see the tool.

You are accidentally animating your scene (e.g. pressed space) and some tools do not show during the animation. Your image shows the Anim Player at the bottom of the screen, which means you are animating.


How can I subdivide this surface or what do I need to do to the surface to make it able to subdivide I am building a tunnle. I used torus meshes to build the roof and sides and then just added a face to the bottom.

problem is that I want to subdivide it and can't seem to. When I try to just hit subdivide nothing happens. Then I tried applying sub-surface mod and the mesh deformed.

What can I do to the mesh to divide it up??

Explanation

Probably that face used for the ground is an n-gon. It isn't possible to subdivide an n-gon directly to produce predictable results, all it does is add vertices to the perimeter.

On the left is a similar structure that has edges spanning to each opposite vertex. On the right the face was generated in one go by selecting all perimeter edges and pressing F to generate one face (an n-gon)

and that's OK until you try to apply a modifier like Subsurf, because you don't have any control over the way Blender internally constructs the n-gon geometry.

Solution

Judging by the geometry I see in your image, it might be possible to select the n-gon, then press Ctrl+F to get the faces menu and select option 'Triangulate Faces', this will make initial cuts. Then Ctrl+F again and select 'Tris to Quads`. This might produce the following geometry.

Realistically.

Once you get a bit more practice with Blender you'll probably approach making a tunnel in a different way.

An efficient way to make a tube/tunnel is to create a profile shape and then use that as a bevel object for a curve.


How to create Rave/Strobe (Colour changing, flashing) lights in a Cycles animation I'd like to have a "Rave/strobe" lighting effect, lots of various point lights all around the scene while the animation goes on, all rapidly changing colour in random patterns.
Is there any way to do this?
I do only have a short amount of time to finish this, so a easily understood and beginner level explanation would be greatly appreciated

F-Curves modifier
Use nodes for your lights.
Add a HSV (far) Color ramp to feed the Emission shader color.
Now you just have to keframe the Factor of the color ramp and the Strenght of the emission node to a starting value.
Open the Graph editor and add a Noise modifier to each of the keframed channels and adjust the parameters to suit you needs. Factor should bounce between 0 and 1, while for the strenght you can go wild.

You can even use/combine others modifiers (sine, stepped interpolation....) to achieve other results.


How to make a frame out of edges So I have this shape that I want to turn into a sign.I want to make a black frame around this on these selected edges using materials.How can I make the edges look like an actual frame in object mode?

Extrude the polygon to create some depth for the sign.
Inset the polygon to create the width of your frame.
Extrude the polygon inwards to create the inside faces of the frame.
Assign materials in the Properties panel.


Can Freestyle Visibility accuracy be improved? It seems to me the freestyle visibility computation is erroneous. I am getting lines where they should not be visible.
This is the scene I am trying to add freestyle lines to:

This is the result including freestyle lines:

As you can see, it seems you can partially see through some of the geometry - for example the axis on the right side. On the other hand, some lines seem to be missing as on two of the screws.
To clarify, this is what's wrong with it:

The freestyle settings are pretty common ones - you can't even adjust anything regarding the visibility.

I need to get rid of these artifacts. My guess is that I am missing precision somewhere - I tried adjusting the camera near and far limits, for example. I also searched for a way to set the depth resolution. If there is such a thing, I didn't find it. The result is the same for Eevee and Cycles, by the way. It also does not seem possible to composite the image by myself, as the new Freestyle Render Pass (new in 2.83.1) does not have a Z Buffer I could use to merge it to the rest of the image.

As far as I can see, you do have a loss of precision .. due to the topology of your model.

Your model has many, many duplicate vertices.. they have to go first.(M Merge > By Distance)
But even then, the topology is very extreme, in places. The only fixed data-points the renderer has to work with are vertex locations. The rest is interpolation - of normals, shading-point locations, everything. If a rendered polygon is a very long thin triangle, then you're running into interpolation inaccuracies near its center.

Flat surfaces are OK, interpolating between a value and itself doesn't present a problem.
As a quick hack, subdividing the surface of the long shafts restored their opacity to Freestyle, but a repair of the topology would make a better job of it. You might get away with replacing the shafts  with dimensioned, quad-based cylinders, with a few subdivisions of their length.
Raising the nuts so their bottom edges are at/slightly above the plate they are  screwed down onto, makes them visible to Freestyle without changing the edge selection settings. (Some are buried at the moment)
Introducing per-face-vertex normals, by switching 'Autosmooth' on, with appropriate, (quite high for these elements,) threshold angles, will help keep smooth shading without overdoing the poly-count.


In Blender, simply mix two image layers like in Gimp In Gimp I've got two layers with identically images with text in middle grey in the foreground on a black background. The lower layers's mode is set to 'normal' while the higher one's is set to 'addition'.

Moving one layer against the other leads to the effect, that those image parts alter to light grey where the middle greys overlap.

How can I achieve this behaviour in Blender?

Edit: Ok it looks like it's not what you're looking for, you want 2 different planes and I give a solution for one plane:

You could simply mix your 2 pictures in a Color > MixRGB node (set on Mix):


Is there a way I can randomize the sample seed? I want something so that when I hit Render, I get a certain noise pattern but then when I hit render a different time, without changing anything, I get a different one. Is there a time-based randomizer for the sample seed?

I'm using 2.8.

PS The clock button isn't useful for me because I want something where I can be on the same frame and get a different noise pattern

Let's put it into an  add-on that one can install once and forget about it:

bl_info = {
    "name": "Random Render Seed",
    "author": "Martynas Ziemys",
    "version": (1, 0),
    "blender": (2, 80, 0),
    "location": "CyclesRenderSettings",
    "description": "Random Render seed EVERY TIME before rendering",
    "warning": " ",
    "wiki_url": " "
                "",
    "category": "Render",
}
import bpy, random
from bpy.app.handlers import persistent

@persistent
def RandomSeedHandler(scene):
    bpy.context.scene.cycles.seed = random.randint(10, 1000000000)

def register():
    bpy.app.handlers.render_pre.append(RandomSeedHandler)

def unregister():
    bpy.app.handlers.render_pre.remove(RandomSeedHandler)

if __name__ == "__main__":
    register()

If this is copied to a new text block and saved with .py extension it can be installed as an add-on.