How to fix my procedural chocolate bloom nodes My goal

My achievement

My problem:
Most nodes are guessed because I can't properly follow the [0]tutorial since my version of blender is newer[1]
[0] https://www.youtube.com/watch?v=-KO_qkM93q8
[1] Downgrade to what version to cover most tutorials?
Update
I followed @Blunder's excellent instructions step by step, yet I'm not getting the same result. In particular the bloom of sugar and fat seem flat and even glossy instead being additional material on the chocolate coat. What am I missing?

The mistake you did here is that you used a painted scratched metal shader for chocolate - and that 1 to 1 including the metallic value(!). This results in delicious chocolate for robots ... or tasty chocolate robots? ;-)
You can use the procedural imperfections from this shader setup for the chocolate bloom and (in other cases) you can use the Metallic value in Eevee to fake colors (like lipstick, hair shading, etc). But I would not recommend Metallic for chocolate.
You will get a much better result if you use the Roughness value for the chocolate instead.
Let's start simple and make a simple chocolate shader.

make a chocolate bar. In Edit mode, scale down the default cube, subdivide it, select the 4 top faces, insect them and pull them up a bit. In Object mode, add a Bevel modifier to make it less blocky (Width, 0.01m, 3 segments, Limited to Angle, 26°)
then set up a simple shader with little Base Color variation and Roughness variation. This can be done easily with Noise textures. Last but not least, give it a bit of Subsurface Scattering to make it look more organic. No metal is here involved ;-)

Now let's evolve this to the sophisticated chocolate with imperfections shader.

add the shader node setup for the procedural scratches (of painted metal) from the tutorial video and adjust it a bit
most important: don't use the Metallic slot but use the Roughness slot
adjust the colors of Color Ramp for the base color as you like. Insert a light brown color for the imperfections
add a Noise texture and Mix RGB node for the Base Color (top right in the screenshot) to create some darker areas as shown in the reference image
(optional) add seams and UV unwrap the chocolate bar to get rid of texture compression at the sides
use an HDR image for the world background (and for Eevee an extra light).

The shader in this example is from the linked video with the "Voronoi Cracks" update for Blender 2.81, plus some noise in base color and UV mapping for little rotation as described above.
Rendered example (Cycles, 128 samples, Adaptive Sampling, NLM denoiser (checkbox), 50% size)


How can I move lights in Blender 2.8? I am not able to move lights in Blender 2.8 in my MacOS. I place the light but I can't move it around, I've tried every key I could find.

Just so this question has an answer for anyone else who might find it:

Select the light in the viewport by left clicking on it - it should be highlighted in yellow.
press g, then move your mouse to move the object. If you want to move it along a specific axis, you can press g, and then press, for example, x, to move it along the x axis. if you want to moe it a specific amount, you can type the number of meters to move it after the axis of movement (e.g. G > X > 0.5 to move it 0.5 in the +x direction).


How to create ship painted metal panels material? Can someone tell me how i can get similar bumps on a surface as the images below

So far i have just unwrapped the hull and used the following material with a musgrave texture.

The model can be downloaded here
I would like to add some realism on the hull so any advise is highly appreciated!
P.S Rendering with cycles.

First, the initial results are good.
I would say don't connect the same thing to both normal sockets.  Do use the clearcoat normal (and I'm a fan of including whatever level of microdetail you want) but consider mixing in much larger scale imperfection as well, to try and coax this type of imperfect reflection from the clearcoat layer.

Make another bump node for the surface Normal socket.
Perhaps this type of wave texture:

And maybe add (clamped) some noise in for good measure:


How to move a Cut Loop and Slide using a measure Im using centimeters as unit of length and I've created a plane.

Now I want to make a edge loop and place it at 6cm from the left edge of the plane.

I went in Edit Mode, pressed CMD+R placed the Edge Loop at the left edge of the place LEFT CLICK, pressed G entered Y inserted 6 but nothing, the Edge Loop is not moving.

What I'm doing wrong?
Thanks

Add the Edge Loop and place it as you did before. Without deselecting it, press N to bring up the sidebar and select the Item tab. Here, you can view and edit the exact location of the selected loop cut. Just click on the X, Y or Z values.

An easy method to get an exact value from the left edge is to snap the loop cut onto the left edge of the plane (before left-clicking to apply the loop cut). Then, apply the loop cut and add 6cm to the Y value in the sidebar.


Blender save files wrong I'm really new to Blender. I have problem with saving .blend files. When I save file in Blender, and try to open in another Modeling app, it's just nothing. I think this is of ngons, but i don't know what to do. http://www.mediafire.com/file/12u2csyge7ff7d9/file.

Blender saves the files correctly.
Ngons have nothing to do with this (always search for the meaning of words before using them).
Different applications support different formats of 3d objects and object attributes. No single application is compatible with the many different formats that exist.
To open the files in a different app, then you have to export in a format that the other app can deal with.
When you convert an object to another format, not all attributes (textures, animations, constraints, modifiers, armatures or simulations) will be saved a s part of a format that does not support such attributes.


how do I get blender to stop rounding up my dimensions? I'm using 2.8 and If I have an object that is say 10.75 on the z axis the read out will change to 10.8 once I've hit enter. It doesn't change the dimension to 10.8 and if I click on the box again it shows me that it's 10.75. It mostly just annoys me and makes me constantly click the box just to double check that my dimensions are correct and I haven't made a mistake.

By default blender uses metric measurement system with Unit System set to None and rounding to 3 decimal places wich best suited for real world objects:

If you using Impereal Unit System rounding wich default to Feet rounding can be from 0 to 3 decimal places. This can be inconvenient when manipulating with a gizmo.

In this case, you can use Length in Thou wich meant "Thousandth of an inch":

For more complex cases: work with micro or macro objects - suitable overriding of Unit Scale:


Get visual transform of object through python I'm trying to save transform matrices of objects into a text file using python. These objects are animated using armatures. I tried to use the "matrix_world" field but that only contains the base value. It's possible to do similar to a mesh which gives a transformed mesh (using the animations and modifiers, etc) but that does not contain the transformation matrix that I need.

Is is possible to get that transformation matrix which is used to render the mesh in the view (basically that matrix which is created using the base matrix plus the animations)?

As your mesh is composed of multiple pieces that are posed with armature, the mesh itself has only 1 origin and 1 matrix transform.

To get the transformation of pieces you need to extract transformation of those pose bones.

You can use bpy.data.objects["Armature"].pose.bones["Bone"].matrix added to your armature global transform matrix or also you can use this answer:

How can I manually calculate bpy.types.PoseBone.matrix


Imported .3ds models when rendered become transparent When I import a .3ds model and render in front of an image it is transparent and loses its material.  What an I doing wrong?

One of your issues lies within the Render Layer options. You need to have no mask layers, and you need to move the objects to separate layers. To disable the transparency of the background you can go to Render Settings > Film and un-tick the Transparent checkbox.

Feel free to comment if I have not addressed your issue, your question is rather vague.


In single image render trail of moving objects I want to render a single frame of an animation and would like to have some of the moving objects to be rendered as a trail between either

the beginning of the animation (frame 0),
a particular number of n frames or
the previous keyframe,

and the current frame.

The objects I want the trail to be rendered of are markers on a human body (like, little red dots, i.e. spheres with a 100% emissive red material, on the shoulder, elbow, hand of a humanoid figure)

The reason that I want the animation being rendered as a trail of the markers is that I want to use the image in a printed technical documentation that describes a particular motion. For obvious reasons an actual animation is not possible in this case.

I have already tried rendering the trail of the markers by using motion blur but the results were far from what I would like them to look. Furthermore the motion blur does for some reason not really follow the actual trail of the markers (I don't know why) and is also influenced by motion of the camera.

I would like to avoid post-composition of multiple frames by hand.

One idea would be to render only the markers for the n frames before the current frame with transparent background, fully render only the current frame and blend the frames together.

Is this possible in blender? Can it be automated? How?

It is possible by using Animation nodes.

Here is a setup for duplicating and distributing objects on every frame:

  there are multiple markers that I would like to render the trails of.
  Furthermore it seems impossible to set a maximum lengh of how far the
  trail goes into the past.

For more control nodes are more complex. This node-setup gets objects from group and arranges markers between selected frames:

I provide blend-file (note, AN must be enabled):


Timeline Jump Distance Change Pressing Shift+Up arrow/Down arrow causes marker to move 10 frames in a given direction. This being in the timeline that is.

What I'd like to have it do is jump 12 frames to accommodate half second intervals.

Attempting to keep robust animations.

In User Preferences (Ctrl+Alt+U), go to the Input section. In the search field on the right, search for shift up arrow (be sure to set your Filter Type from Name to Key Binding). You'll find the binding for the Frame Offset operator. If you expand the operator, you should see a Delta setting in the lower right. It's default value is 10. You can change it to 12 (or whatever other value you want).


How do I add high detail to smooth surface? First off, just a quick back ground. I'm new to Blender, but not new to modelling. I've have a go in the past with good results.

However, I'm trying to model a Helmet from the game Destiny but in high detail for 3D printing.

I'm trying to replicate the carvings on this Helm as seen here..

This is what I have so far..

Now would I be best selecting the faces of the plane, duplicating and modelling the detail as a seperate object, or subdiving the original mesh?

Cheers
Steve

I'm familiar with two approaches that support 3D printed output: Subdivision with a height map or sculpting with dynamic topology.

With a height map, you'd need to subdivide the appropriate faces then apply a map you've prepared to define the raised areas on those faces. This might be attractive if you prefer working with bitmaps, but it introduces some inefficiency because you need to subdivide a lot to get certain details just right. Here's some information on using height maps in Blender: http://johnflower.org/tutorial/make-mountains-blender-height-maps

Sculpting with dynamic topology might be more efficient in this case because it adds vertices only where they're needed. Here's a video that introduces sculpting with dynamic topology (he talks about and demonstrates why dynamic topology is important for the first four minutes and then he gets into it): https://www.youtube.com/watch?v=opsKPCCFbr4

Of course you could also hybridize between these options: start with the height map at some moderate level of subdivision, apply it, then switch to sculpting with dynamic topology to add detail.


Why ray_cast is behaving like this? Why the result of ray_cast function is giving me that result?
The hit point should be Vector(0.5, -1.0, 0.0), but it is returning Vector(0.666..., -1.0, 0)

I have tried a lot of combinations to try to understand what is wrong, but no clue of what happens, so I decide to ask it here.

Thanks to batFINGER, I found the error. The ray_cast function should be supplied with a point (v1, in my example) and the normalized direction, reached by (v2 - v1).normalized(). Now it is working as expected.


Can't see texture through Principled Node? Maybe I am missing something obvious but when I connect my image texture to principled shader (using PBR Material Nodes) it doesn't show the texture in rendered viewport, or in materials viewport.

But through typical Diffuse Node, everything works fine. Using cycles.

Halp?

Ok I found the reason. My Subsurface scattering was maxed to 1, but if you want to see the texture, it needs to be lowered.


Have location of grouped objects relative to parent object I am creating a wall section which will be a wall with a hole and in the hole's place a couple of doors and so on.

For ease of putting things in place I first create an empty node. Then add a wall and doors as children of the empty node. If I relocate the empty node, the meshes of the wall and doors follow along.

What bugs me is I want to locate the doors and wall relative to the location of the parent, empty node. How do I do this? It seems that even though an object has a parent node, the Location in X/Y/Z is specified in the global world. It would be easier to specify this relative to the parent node. So with a pair of doors I could just set something like X: -0.5 for the left door and the right door would get 0.5. Is there any way?

A child always lives in the local space of its parent. You can easily check that by noting the current coordinates of a child that show up in the properties panel ("N"), moving the parent, and then comparing the new coordinates of the child with the first set. They shouldn't have changed, i.e. they can't be global).

At the time of parenting, the child object takes note of the parent's current state (location, rotation, scale) and stores it in child_object.matrix_parent_inverse. Blender applies this correction matrix to the parent's origin before calculating the child's effective global coordinates. (As it is the inverse of the original parent's matrix, it will "negate" the effect the parent had at the time of parenting, thus seemingly keeping the child in the global coordinate system.) Here is a nice official description:
http://wiki.blender.org/index.php/User:Pepribal/Ref/Appendices/ParentInverse

Or if you prefer it mathematically (at least this is how I interpret blender's behavior):

parent.matrix_world * child.matrix_parent_inverse * child.matrix_local

(where parent.matrix_world can of course be influenced by other parents and such).

Now to get rid of the correction matrix, and to be able to place your doors at x = +-0.5 of the parent, simply select the children in question, press "alt+p" and select "Clear parent inverse" (Or in the 3D View, go to "Object"->"Parent"->"Clear parent inverse"). This will set the matrix_parent_inverse to the identity matrix and place the children in the parent's coordinate system according to the children's local coordinates. (You could get the same effect by parenting while the parent is still at the origin with no rotation and scale==1.)


How does one animate time in the VSE? I'm trying to move between slow motion and normal motion on a video/audio strip smoothly, but am having problems animating this.  I've tried Individual objects and Entire scene and Time Remapper addon  but cannot get it to work.

When i try using the NLA editor for to control the speed of an individual video strip, i dont seem to find the check box Animated Strip Time

I would like to see a video screen cast of how one does this on a video strip.

In the VSE, the "multiply speed" value of a "Speed" effect strip can't be animated. You'll have to :

uncheck the "Stretch to input strip length" box,
check the "Use as speed" box,
set the "Speed Factor" value to 1 (so the video will be played at normal speed)
animate this value as you need:

greater than 1, playback will be faster,
between 0 and 1 the playback will be slower.

You may have to click the "Refresh Sequencer" button to see the result.

Note that the sound won't be affected by this effect strip. I don't know if you can time-remap a sound in Blender.


Four bones counted as one? I'm somewhat of a beginner and I'm helping out a group of my friends by creating unity assets for them in blender. Recently I came across this avatar (made by Kevin Iglesias) and I've noticed its hand looks like it's made up of 4 bones, but is still considered by unity as a single bone (image below).

I can't find any mention of it anywhere; is it even possible to create something like this in Blender? Is it two different armatures that are parented with eachother?

I wrote to the author and he had explained it, I'll post the anwser here in case anyone else encounters this problem:

That's the representation in Unity of having 4 bone childs not connected.
In the picture below you will see that effect is achieved by having 4 not-connected-to-parent bone childs of the hand bone.


boolean modifier fills up the intersection area I want to create a cut in a cube so as to create a hollow pool of water in the middle of the cube. However, when I apply the boolean modifier and remove the object used to cut into the cube, I see no actual difference. The cube is still completely solid. Only in edit mode can I see that a boolean operation has been performed, but unfortunately no hollow area is created. I hope someone can tell me what the issue is here.

The problem is the topology of the small cube, it is made of separated faces, so the Boolean operation can't work properly. To solve this, you need to go in Edit mode, select all, and W > Remove Doubles, so that it joins all the faces together and make a real cube. Then your Boolean will work properly.


How set actuator properties while the game is running? When I call bpy.data.objects['Enemy'].game.actuators['<name>'].target = bpy.data.objects['XX'] the value is only updated after pressing Esc to quit  game and then hitting P to start the game again.

How can I update the target in real time,  without the need to stop and start the game again?

The bpy module does not work in the game engine, use the bge functions instead.

For instance:

objectList = bge.logic.getCurrentScene().objects
bge.logic.getCurrentController().actuators['<name>'].target = objectList['XX']

More information can be found on the bge.logic and bge.types pages of the blender python api.


Can't UV unwrap a sphere added with Python I'm trying to create a uv sphere and uv unwrap it, both in python. That is, I can create the sphere, and I can uv unwrap objects, but I cannot unwrap the sphere. I can unwrap a manually created sphere, though.

The following script creates one sphere, and unwraps all objects in the scene. Create your own sphere manually, run the script, and you'll end up with two spheres, one of them uv unwrapped correctly, while the other is not. What goes wrong here?

import bpy
import bmesh

from math import radians

context = bpy.context
scene = context.scene
vl = context.view_layer

# Create a sphere

# Create an empty mesh and the object.
mesh = bpy.data.meshes.new('Basic_Sphere')
basic_sphere = bpy.data.objects.new("Basic_Sphere", mesh)

# Add the object into the scene.
bpy.context.collection.objects.link(basic_sphere)

# Select the newly created object
bpy.context.view_layer.objects.active = basic_sphere
basic_sphere.select_set(True)

# Construct the bmesh sphere and assign it to the blender mesh.
bm = bmesh.new()
bmesh.ops.create_uvsphere(bm, u_segments=32, v_segments=16, diameter=1)
bm.to_mesh(mesh)
bm.free()

# Unwrap all objects

for obj in scene.objects:
    if (obj.type == 'MESH'):

        vl.objects.active = obj
        obj.select_set(True)
        print(obj.name)
        lm =  obj.data.uv_layers.get("LightMap")
        if not lm:
            lm = obj.data.uv_layers.new(name="LightMap")
        lm.active = True
        bpy.ops.object.editmode_toggle()
        bpy.ops.uv.smart_project()
        bpy.ops.object.editmode_toggle()
        obj.select_set(False)

Any help is appreciated!

Select the Faces.

The Smart UV unwrap (or most UV ops) rely on faces being selected. For objects added via an add mesh primitive operator all verts, and hence faces are selected by default. For meshes created by bmesh the opposite is the case.

Simply select all faces when you create the bmesh and the UV unwrap will work as expected.

bmesh.ops.create_uvsphere(bm, u_segments=32, v_segments=16, diameter=1)
for f in bm.faces:
    f.select_set(True)

Related:

Smart unwrap using script  (Looks somewhat familiar)

How to UV Unwrap and Scale UVs with Python (while in object mode)?

This way can lose the edit mode toggle and use no operators.

import bpy
from bl_operators.uvcalc_smart_project import main as smart_proj

context = bpy.context
scene = context.scene

meshobs = [o for o in scene.objects if o.type == 'MESH']
for o in meshobs:
    o.select_set(False)
for o in meshobs:
    context.view_layer.objects.active = o
    o.select_set(True)
    smart_proj(context, 0, 66, 0, True, True)
    o.select_set(False)

I am trying to create a Script that does a Smart UV unwrap of seperate connected parts of a mesh


grease pencil as raster How to set grease pencil to draw as raster ? if i'm doing fast curve stroke, i hate when blender convert it into segmented curve (stepping curve). Is it possible to have a smooth line like doing a sketch using raster app like sketchable etc.

In Drawing Mode > Active Window and Workspace Settings > Options,

Turning up the "input samples" to a higher number works. Also switching on the "Post Processing Settings" and adding more Subdivision Steps should help as well.


unable to run two (or more) scripts together I am doing some rigs for a project and I have a problem that could not give solution, I have in scene several rigs that are variations of the same, the rig has a simple UI that basically reads and allows to modify properties , The problem is that when linking the characters (when there is more than one on the scene) when running the script one is disabled the other, the question is, how can I get both of them run at the same time, on the one hand I might be doing a script add that runs two or more scripts listed is that possible? Or which would be the correct way for self-executing to work well? Sorry if the question is silly I'm pretty good at rigs but I'm still learning blender scripting.

here is a sample of the Character_UI

import bpy

class RigUI(bpy.types.Panel):
    """Rigg user interface"""
    bl_label = "Rig UI"
    bl_idname = "PT_Rigg UI"
    bl_space_type = "VIEW_3D"
    bl_region_type = "UI"

    @classmethod
    def poll(cls, context):
        return context.active_object.type == 'ARMATURE' and context.active_object.name.startswith('koya_proxy')

    def draw(self, context):
        layout = self.layout

#IK FK switch

        obj = context.object
        bone = obj.pose.bones["gen"]

        row = layout.row()
        row.label(text="Cuerpo", icon='MOD_ARMATURE')
        row = layout.row()
        row.prop(bone,'["FK-IK_brazo.L"]',slider=True)
        row = layout.row()
        row.prop(bone,'["FK-IK_brazo.R"]',slider=True)
        row = layout.row()
        row.prop(bone,'["IK-FK_pierna.L"]',slider=True)
        row = layout.row()
        row.prop(bone,'["IK-FK_pierna.R"]',slider=True)
        row = layout.row()
        row.prop(context.active_object.data, "layers", index=16, toggle=True, text="falda")
        row = layout.row()
        row.prop(bone,'["Auto - Full Manual "]',slider=True)

#facial

        row = layout.row()
        row.label("Facial", icon='MOD_MASK')
        row = layout.row()
        row.prop(context.active_object.data, "layers", index=6, toggle=True, text="Shapes")
        row.prop(context.active_object.data, "layers", index=4, toggle=True, text="bendy")
        row.prop(context.active_object.data, "layers", index=7, toggle=True, text="Lattices")
        row.prop(context.active_object.data, "layers", index=3, toggle=True, text="Cabello")

#accesorios

        row = layout.row()
        row.label("adicional", icon='MOD_CLOTH')
        row = layout.row()
        row.prop(context.active_object.data, "layers", index=5, toggle=True, text="bend")
        row = layout.row()
        row.prop(bone,'["Fisica_cabello"]',slider=True)
        row = layout.row()
        row.prop(bone,'["ph-vis"]',slider=True)

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

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

register()

Using the rigify addon as an example, you add a custom property to the armature that holds a unique rigID for each rig, then you register duplicates of your operators and panels that are customised for each rigID.

rig_id = "ThisRig"

class Rigify_Leg_FK2IK(bpy.types.Operator):
    """ Snaps an FK leg to an IK leg.
    """
    bl_idname = "pose.rigify_leg_fk2ik_" + rig_id
    bl_label = "Rigify Snap FK leg to IK"
    bl_options = {'UNDO'}
    ....

class RigUI(bpy.types.Panel):
    bl_space_type = 'VIEW_3D'
    bl_region_type = 'UI'
    bl_label = "Rig Main Properties"
    bl_idname = rig_id + "_PT_rig_ui"

    @classmethod
    def poll(self, context):
        if context.mode != 'POSE':
            return False
        try:
            return (context.active_object.data.get("rig_id") == rig_id)
        except (AttributeError, KeyError, TypeError):
            return False
    ....

As an example, if you were using rigIDs of char1 and char2 then you will find the following classes registered -

bpy.types.pose.rigify_leg_fk2ik_char1
bpy.types.pose.rigify_leg_fk2ik_char2
bpy.types.char1_PT_rig_ui
bpy.types.char2_PT_rig_ui


What's the difference between 'unlink' and 'remove' from collection? I did 'unlink' and 'remove' respectively, but really don't know how the two are different. What's the difference between them?

If your object is linked to more than one collection Object > Collection > Remove From Collection will give you the option to remove it from all collections or from one specific collection. Unlink in the outliner on the other hand only removes the selected object link from the collection it is in. If the object is linked to other collections, these will remain.


How to create this effect of embossy surface and repeated pattern with scale? I am very new to Blender.
Right now, I am modeling a 3D for a lipstick bottle (image below).

Question: How to achieve this type of effect as marked in red rectangle in the below photo.

Make a plane and Bend it

The object has two main features: it's cylindrical and it's cover with a pattern. A possible way to approach the problem could be to focus first of all on the pattern and then repeat it on a planar surface that we are going to bend.

The pattern's tile

First step is to model a "tile". I started from the main loop: an half circle. I built the following shape by extruding and ajusting the vertices manually keeping an eye on the flow of the edges. Then I duplicated the single petal around and cut with the knife tool the pieces outside the "ideal" square box in order to obtain a perfect match of the instances borders of the array. Mirror modifier will ensure the symmetry on the X axis. It's important to keep in mind that when a bored ends, the other should start: that's wy the scale is a little rotated and not parallel with the XY plane.

I kept it low poly because I planned to use SubSurf and to be able to make changes quickly.

Note: there are surely better topology for the mesh; I'll present here just a sample. Keep in mind that we are going to bend it on the X direction, so there should be a good amount of edgeloops running from top to bottom.

Deforming a plane

It's now time to add a few modifiers to the object:

An Array modifier that replicate the object in X (set Merge option enabled)
Another Array modifier that replicate the object in Y (set Merge option enabled)
A Simple Deform modifier with Bend mode , 360 degree of rotation and a custom object (an empty previusly created) to manipolate the center of rotation
A Subdivision Surface modifier with Catmull Clark option to smooth the edges and increase the resolution before the final tapering
A Lattice modifier to control the deformation of the cylinder along its revolution axis. It also helps in making the scales smaller toward the end once enabled Proportional edit mode.

The main body of the object can be said inished. You should now proceed to create the top and the bottom pieces and refining the object (removing doubles, building the inside shell, assing different materials...) once you are satisfied with the result of the modifiers. In order to edit the resulting geometry you must apply the modifiers before entering edit mode.

This approach that heavily take advantage of modifiers it's quite flexible and non-destructive, but it is successsuful be used only because your geometry has a polar symmetry.

Tissue add-on cannot be helpful in this case because of the roundness of the shape in combination with the low number of repetition of the pattern (you'll have to rely too much in the subsurf smoothing), while Simple Deform modifier does instead a great job on this aspect.

Result:


How would you create a cd material in Cycles? I know you can use the anisotropic BSDF shader to create the blurred effect but how would you make the weirdly reflected colours you get when you hold a CD to a light.

Here's an image example I found on Google Images:

I want it so that you could create the colours without just using an image texture of a CD

Here's the fake iridescence effect I achieved. Try to experiment with Mapping and Anisotropic nodes settings.

Here's an animated gif (click on a picture below to see a larger version).


How to set weights for a mesh to bend smoothly? I'm trying to make this bend smooth but I'm not sure how If i'm weight painting correctly help would be greatly appreciated : )

From your image, it looks like you don't have any weights painted on your root bone (i.e. the one for the blue part on the left). Adding these weights (and possibly the bone if it isn't there) should allow you to adjust how smooth the blend is.

In order to be able blend between bones, blender has to actually know which bones to blend. To do this it looks at all the bones that have some weight assigned to a vertex and blends the effect of the bones based on the relative strengths of those weights. If a vertex has only one bone weighted to it, regardless of the value of that weight, it will only be influenced by that bone.


How do I make text come out out of an impossible space? I'm looking to recreate the text being generated by two horizontal bars in the Marvel logo https://youtu.be/fqxIrmdtLEk?t=25s (@00.25 secs)
I've already generated the text, just looking for a way to achieve the animation part of it.

Basically you need a text and two couple of cubes.

First couple of cubes: you can simply create a single cube, mirror it (with a modifier, on z axis. Don't apply the modifier) and move it up (Z axis) in edit mode to see it's twin. In edit mode hook the whole geometry to an empty object.

Second couple of cubes: duplicate the first (they will be hooked to the same hook) and in edit mode scale them bigger to cover all the writing.

Convert the text into a mesh (ALT+C) and add a boolean modifier to it (difference with the second couple of cubes).

Now if you move the hook you'll get this:


How to start modeling a square metal profile with holes? I'm new to Blender (switched over from Sketchup) and I'm struggling with the complexity of the program.

I have no idea how I should start modeling a square metal profile with holes.

Can anyone give me any pointers of how I can start?

You can start considering the object symmetries, 8 parts like that:

Thus, we'll try to make it and use Blender's mirror modifier.

As rounded parts are generally more complex to do, we start with them:

Add a circle, with a relative low resolution (say 16 vertices). This will be the center of the shape.

Then duplicate it in edit mode ShiftD and extrude and scale this last one ES to the wanted value.

Here you should have something like this:

As this is symmetrical, from the above picture, we can delete the unwanted part. So, only keep this:

From that, it is only aligning and extruding to be at the dimensions you want:

Now the mirror modifier part:

We need two mirrors,

One to make a quarter of the shape: it uses an empty as pivot rotated 45 degrees.
One to replicate the previous one along X and Y axis.

Here is the setting:

So we now have:

Finally, we can add a solidify modifier to extrude the shape:

Last points:

Use shade smooth (in object mode W then 'shade smooth')
And use autosmooth for the normals (look at the image below)

A blend file with the several steps included:


Strange geometry appears after separating part of mesh I'm trying to copy part of my mesh by selecting, duplicating it, then separating it. Every time I separate it I get that gray thing you see in the image.

To avoid this, I disconnected the particles, separated the mesh, then reconnected the particles.


What options to grow object? I tried to animate my object to appearing like from nowhere. I tried to use boolean's intersect modifier so that I had a box over my object which I animated from down to up.
Very much the same what Chris does on his example:
Sci-Fi Laser 3D Printer Effect
My issue was that sometimes my object totally vanished while the box was coming up and showing more about my object. Or when looking for this from top, there were no faces on up, like he had at 3:19 on his video. I believe the problem could be my object itself. I tried to fix that by merging the closest vertexes, but did not end to perfect solution.
I also tried to use build modifier, but that I feel was a bit uncontrolled, and really did not give the effect of "extrude".
Is there some other options which I did not thought to get similar effect? Or shall I try to continue to fixing my object to get this work?

You could use the Mask modifier.
First you need to paint some weights to vertices in Weight Paint mode.
Go to Weight Paint mode and select your object. Add a vertex group and select Gradient tool. Pull the tool across your object and it will paint the weights as can be seen in the image below.

Next go to Object Mode and give your object a Mask Modifier. Pick the Vertex Group you created earlier and adjust the Threshold. Threshold can be keyframed to make the object appear and disappear.

The more subdivisions your object has the smoother the appearing is.


Convert files from console using Blender I'm trying to import glTF file into Blender and export it as dxf by running a Python script from command line.

I'm able to do this via GUI when I activate both glTF & dxf plugins. I've seen a similar solution for conversion from obj to fbx, which runs fine:

import bpy
bpy.ops.wm.read_factory_settings(use_empty=True)
bpy.ops.import_scene.obj(filepath="D:\\source.obj")
bpy.ops.export_scene.fbx(filepath="D:\\taget.fbx")

However, glTF and dxf are handled via plugins and I've been unable to modify the code since I'm no Python expert

This is untested, but too much to write in comment.

Would say the gltf addon is default in 2.8 the dxf not.  Here is a test script to enable both and set as default and persistent.

If you look at addon info for the two addons in question will note that the folder name in addon folder for each is

"io_export_dxf", "io_scene_gltf2"

this is the key used to enable them using the addon_utils helper method enable, and check if already default and enabled with check

import bpy
from addon_utils import check, enable
bpy.ops.wm.read_factory_settings(use_empty=True)
for addon in ("io_export_dxf", "io_scene_gltf2"):
    default, enabled = check(addon)
    if not enabled:
        enable(addon, default_set=True, persistent=True)

#bpy.ops.import_scene.gltf(filepath="/somepath")
#bpy.ops.export.dxf(filepath="/somefilepath")

Note commented out the operator calls.

See the output in the python console to find and check what properties can be set for operators.

For example export to dxf. Will reflect those in UI panel when manually exporting.

>>> bpy.ops.export.dxf(
dxf()
bpy.ops.export.dxf(filepath="",
    projectionThrough='NO',
    onlySelected=True,
    apply_modifiers=True,
    mesh_as='3DFACEs',
    entitylayer_from='obj.data.name',
    entitycolor_from='default_COLOR',
    entityltype_from='CONTINUOUS',
    layerName_from='LAYERNAME_DEF',
    verbose=False)
Export to the Autocad model format (.dxf)

Note properties listed in long winded operator call above are defaults, and only need to be set when non default (eg filepath)

As mentioned untested.


Fill space between inner mesh my problem is the following:
I've made an object in blender and now I've begun applying material but I've noticed that I've added multiple meshes between the innermost and the outermost. This is quite annoying for the part which should have a glass material (the "vizor" as it is visible in the captures). In fact I've first tried to select face without limit selection to visible but as there is the back of the object which is also selected this have not really worked.

EDIT: Ok I'll try to clarify my issue, I've uploaded another capture, this time only one  half of the mesh. As you can see there is multiple inner faces especially in the red rectangle (in the image attached) and those inner faces are those I want to assign material on (or delete all other than to outermost)

I went with the delete all but the outermost option (well, I kept two layers of the four you had). You have a circular opening in the top of the inside of the helmet. Select all the faces of its rim. I used circle (C) select for this and panned around until all were selected.

Delete these faces (X then F)

Select one face on the unwanted geometry

Select linked (CtrlL)

Delete everything that's selected (X then F)

It now looks like this (with all selected, zoomed out and limit selection to visible disabled)

I hope this helps.


How could I have an object's Z axis align with the first derivative of is location F-Curve I want an object to follow a path in space (specified via F-Curves, or by clamping to a Bezier curve), but I want the Z axis of this object to always be tangent to this trajectory (the same way that the engine of a train is approximately tangent to the train tracks).

I've tried using constraints: having an empty move along the "train tracks", and my object following closely behind, using a track-to constraint (so the object's Z points to the empty). I've paired this with a limit distance constraint (target is again the empty), but the result is not visually convincing -- it looks like the object is short-cutting the turns, as opposed to staying on the "train tracks".

If the goal is for an object to move along a curve (e.g. Bezier) with one of its axis aligned with the curve's first derivative, as suggested by @atomicbezierslinger, you can use a follow path constraint. For example, if we want the object's Z axis to be aligned with the curve's tangent:

Set Follow  Curve to true.
Set the Forward axis to Z
Set the Up axis to either X or Y (setting to Z will not work, and the object might not move at all).


Blender mirror error on objects When i export a object that i have mirrored it becomes transparent. when i undo the mirror effect it does not become transparent. does anyone know why this is happening?

As moonboots already mentioned, it sounds like your problem's issue is that your mesh's polygons are flipped the wrong way. You can easily recalculate polygon normal directions by using the [CTRL+N] shortcut. If you wish to recalculate only selected polygons, select the desired polygons in edit-mode, than use the [RMB] shortcut to bring up the edit shortcut menu, then choose the Mesh Tools -> Flip Normals selection.
Some documentation.
https://all3dp.com/2/blender-recalculate-normals-simply-explained/


Noob question about simple geometry Im trying too create a basic 3d floorplan in blender (First time using it) however, I cant seem to figure out how to "Intrude" A wall after ive extruded it. In my example, The wall is too long and i wish to cut it down a bit. The photos attached will explain what is happening. there must be an easy way. online people tell me to inset the face yet that creates a hole or the same as extrusion. Any tips would be appreciated :)

The simplest solution should be to move the faces along their normal. It's sort of an extrude, but without creating new faces. So you can re-position a face that was previously extruded. To do it, press alt+S. Move the mouse up and down to see the faces move. Click a mouse button when you are satisfied.

One thing that I often do is create a new edge loop that I position where I want it. Then Dissolve the unwanted geometry. If you dissolve it correctly instead of removing it, you won't have to create new faces to fill in any holes. Use ctrl+R to start creating an edge loop. Move the mouse over the geometry to position the edge loop. Click the mouse to continue. Now you can move the edge loop up and down with the mouse. Click again when you are satisfied and you are halfway done.

Select the geometry you don't want. For instance, right click the outermost face. Type ctrl++ to expand the selection until you have everything selected. Or select using right click while holding down shift. Type x and select "Dissolve faces".


Q: Grease pencil, how "Anti-aliasing Threshold" works? With: Eevee, 2.8.6, 2.9.0, macOS 10.15.4, Radeon RX 580.
My Temporal Anti-Aliasing is quite bad, it's very anoying.
My TAA is good for meshes through to Film>Filter Size parameter.
If I put "1" to "Anti-aliasing Threshold" it's much better than "0", but not enough. If I try more than "1", it doesn't change anything, it doesn't blur the GP, even if I put "1000".
I've tried to increase Sampling>Render, without success.
In "Hero" by Pepe Land, I can see there is no flickering due to aliasing, so it must be possible.
Here is my file, thanks!
:-)
Link to my file

There was a bug with Anti-aliasing  in pre 2.9 versions. Are you up to date?
If you're experience flickering lines when moving the camera or an object then this is a known bug. I believe the fix at the moment is render in double the size and then compress. This works for me but naturally takes significantly longer to render.
Thanks
Matt


Automatic Weights doesn't work well on a cloth simulation mesh, but works perfectly on a handmade one I have created a mesh using a cloth simulation and sewing, after I applied it, I merged all sewing points and applied an armature deform using the auto weights. It works badly, like this:

After trying everything I decided to try the auto weights with this armature with increasingly more complex meshes until I ended up replicating the mesh manually (magnet + extrude + F) so that I have the exact same mesh, and I applied the auto weighting, and now, it works much better:

Both meshes are the exact same and still, the auto weights work badly on the first one: why does this happen? Is there some king of atribute in the original object which is disrupting the auto weights system?
Thank you for your help!

Ok, so if someone is in the same situation as me, I found a way to make the Automatic Weights work: you must  apply a remesh or some kind of modifier which will change the mesh, for example: I applied a wireframe with very low thickness, merged all verts automatically with Auto Merge, rebuilt all faces with Mesh - Clean Up- Fill Holes; and now it works perfectly. So now you end up with exactly the same mesh, but the Auto Weights will work.
Probably there is a much simpler and sophisticated way to do this, but this way works.


Move connected vertices along their individual normal paths? Is there any way to move connected vertices along their respective normals? Similar to the way the solidify modifier works, I want to push the vertices in the directions of their normals.

With orientation=normal and origin=individual, it works as long as the vertices are not connected by an edge. Is there any way to achieve the same thing when they are connected? It seems the individual origins concept works based on disconnections in the mesh, like islands. I'm assuming that is why it fails to pull this off.

I appreciate any info

Okay, so apparently there is something called the shrink & fatten tool. Use Alt + S to activate it. Make sure the pivot point setting is not on individual origins. It looks like pretty much any other setting will work, though. Individual origins applies it onto island paths. The other modes apply it to each specific vertex path.

Hope this helps someone looking to do the same!


Conditionally apply texture based on object behind? Not entirely sure how to concisely describe this (or what to Google for). I guess it can be done somehow by using conditionals on the light path..?

I have this scene:

Basically, a "terrain" mesh, and two flat planes intersecting it. Now, I would like  to apply a certain texture on the "Yellow" plane, but only on the area directly over the terrain, not over the blue plane.

It's probably clearer what I mean in a top view:

(The clearly yellow area).

The idea is to get some combination of nodes that will give me a 0 or 1 result I can use as "factor" to a mix shader.. but I got stuck trying to find how that could actually be done.

Update: to clarify, I want to apply the texture in the region hit by "vertical" rays, i.e. parallel to the object normals / Z axis, not the camera ray.

You need to use the Geometry node with drivers

Basically Blender analyses each every portion of the mesh, and for that portion the Geometry node returns its position.
The Separate XYZ node extracts the height from that position vector
The two Value nodes get their input from two drivers (in the picture there is one of them) that copy the Z position of the two planes

With the two Math nodes, set to Less Than, you calculate if that mesh portion is under one of the two planes. The values you get are 1s (White) or 0s (Black)
You can use those values as the factor input of two Mix shaders to get your final color

Of course if you have textures you can put them instead of the RGB nodes, replace the Mix nodes with Mix Shaders

EDIT

This is your setup in case of horizontal planes. In case of tilted planes there is more math involved, but it's absolutely possible


Set Object's "Viewport Display" according to Workspace I do a lot of retopology and I want to make a new Workspace exclusively to it. So it should have Backface Culling (Viewport Shading) and In Front (Object Viewport Display) options turned on.

I can set the Backface Culling to work dependent on the workspace, but the Object Viewport Display is not changing. Can I make it work?

Just ran into this issue and I accidentally solved it by going to solid viewport shading instead of material viewport shading in the top right of the viewport. Hopefully this helps anybody else looking for an answer.


Updated: Cycles show missing Texture (magenta)... until i reconnect the materialnodes I have a problem with a textured object in Cycles:

On the Render and Viewport I see a missing texture, but no texture is missing.

It seems not to be a matter of included or external stored textures. In both cases I have the same problem.
The texture shows up correct in the Viewport after reconnecting the Materialnodes in the Node-editor, but after switching to solid Viewport Shading and switch back to rendered it shows the missing-magenta again.

The material nodes I used are the ones I always use and they worked fine until now. The problem seems to be independent from the used Blender version. Tested the scene in several versions.

How can I fix this?

To explain some uploaded Screenshots:

pseudo-missing texture:

after reconnecting nodes:

Update:
I use the following Node-setup:
Texture Coordinate (UV) ->
Texture Group (DiffuseMap:Color-Data, Glossiness-Map: Non-Color-Data, ReflectionMap: Non-Color-Data, Normal Map: Non-Color-Data) ->
PBR Dialectric Nodegroup (like the one from Blenderguru Tutorial) -> Output

After some more experiments with that problem i found out that the problem seems to be triggered by the Reflection Map. When it's disconneced it works fine. When i connect it then it still works in the viewport and it has the right influence on the used Material. After switching the Viewport Shading to solid and back i have the Pseudo-missing-Texture (Magenta) again.

Update 2:
Tested a bunch of different connections between the nodes... but after quite a lot testing i can find no conclusion where the problem is.

Picture of the Fresnel Node-Setup:

Here are some more pictures of the node-setups that i tested:
The ones that seem to work:

And the ones that bring me the missing-error:

Also tested mixing the Glossy and the Diffuse BDSF with a fix 0.5 value instead of using the Reflection Map... that was resulting in absolute random behavior. Sometimes it worked... sometimes not.

Found a solution!
Converted the 16-bit png-files into 8-bit png-files. With these the problem doesnt seem to appear.
But I'm still curious. Perhaps someone has an idea why that happens with the 16bit Textures.

Found a solution! Converted the 16-bit png-files into 8-bit png-files. With these the problem doesnt seem to appear. But i'm still curious... perhaps someone has an idea why that happens with the 16bit Textures.

I'll have a look at the bugtracker... to see if it's been reported. If not i'll post that in there. (Thanks Matt!)


Compiling Blender - Python 3.9 I've been compiling Blender for a short time now and use the scripts make update and make.
In one of the recent updates, it seems the python dependency changed to Python 3.9

CMake Error at CMakeLists.txt:842 (message):   At least Python 3.9 is
required to build

So of I installed Python 3.9. on my system. I then used
# update-alternatives

I now have:
# python --version
Python 3.9.2

But when I run make, I still see the original error.
# make

Configuring Blender in "/xxx/yyy/3D/Blender/blender-git/build_linux" ...
CMake Error at CMakeLists.txt:842 (message):
  At least Python 3.9 is required to build

I haven't been able to discern anything in the error logs that can help me out.
Does anybody have ideas how to fix this?

make fails because of Python version, but I did not realise that Blender comes bundled with it's own Python package. So in the latest make update the code / scripts came bundled with latest Python version that they should be built against.
The following article gave me a hint for the solution.
Building Blender with a different Python version
I edited ./build_linux/CMakeCache.txt
changing  the all of the Python version number references
to that of the new version found in
./lib/linux_centos7_x86_64/python/bin/

I could then successfully built Blender from source again.


How to export a scene from Blender, in which I use modifiers and constraints, to Maya and Nuke? I created in Blender ocean and floating object.

How to export this scene to Maya (I need to export this scene to Nuke through Maya)?

Animation of floating object - is not the key animation, made by hand (from key to key, from phase to phase). In order to move "on the waves" floating object analyzes the surface of the ocean.

This is a simple method - I use an invisible object to draw in "dynamic Paint" mode, the area of the ocean where the object should float. And then I make object "copy rotation " and "copy location" (constraints) of this area.
(here is tutorial i used: https://www.youtube.com/watch?v=11F1NRpqrzY)

But I think in Maya and Nuke there is no ocean  modifier and constraints.
How to export this scene?
Thanks in advance!

Yes, it is possible! :) You can use the "Bake action"!

If you have an ocean, and an object that "floats" on the surface of the ocean using the method, described in this tutorial (https://www.youtube.com/watch?v=11F1NRpqrzY)

do the following:

1) Select a floating object

2) Press T and in the left pane, select the tab "Animation"

3) Press Bake Action, select the frame range and check "clear constraints"

4) Voila! You will see a lot of yellow strips in the timeline - the key frames of animation.

Now, if you delete the ocean and sphere by which you drew in the dynamic Paint mode, floating object will continue to move as before.


What is this line coming from the light source and how do I adjust it? Forgive me for this noobish question (still learning ropes of blender) but I'm playing with some of the lights properties, and was wondering what this line is and if there is a way to adjust the length of it. I've circled the line in red in the photo. Currently it surpasses my landscape, and it's kinda unappealing being so long. The lights are area lights. Any help would be greatly appreciated.

That line indicates the direction of a sun lamp.
If you rotate it it will determine the direction for the light and shadows.
Note that for sun lamps the placement in the 3d environment is irrelevant, they just have direction.
To control the size of the line (and it is just an informative line line for you to see the direction) just scale it (press S and drag the mouse)


Can we parse "string" as Driver Variable? I am using scripted driver to changes image texture.

import bpy

def change_image_baby( val,min,max):
    if (min <= val <= max):
        filePath = "//baby_eyes\\eye_0%d.png" % val
        bpy.data.images["Minu Child eyes.001"].filepath = filePath
    return val

bpy.app.driver_namespace['change_image_baby'] = change_image_baby

On bone Movement by using above function as driver I am able to change the images.

Now i want to use same driver function on many other characters.

So I defined "filePath" and "image" name as object property of each character

New driver function

import bpy

def change_image(n,min,max,img,file):
    val = int(n*10)
    # img is image to be replaced and "file" is the file path
    return val
    if (min <= val <= max):
        filePath = file % val # as all my images are in sequence i replacing numbers see above code
        bpy.data.images[img].filepath = filePath

bpy.app.driver_namespace['change_image'] = change_image

and use in driver UI to parse it to custom driver

I am not able to parse string it has to be either int or float. What is the workaround to parse string as Driver Variable?

in this method we try to identify the object that is running the driver then we access its properties ( image and file ):

we add a new property to all scene objects this property is their index in the scene objects list ( we need to run this every time we add/delete an object to the scene ) :

import bpy
for obj in bpy.context.scene.objects :
    obj["index"] = bpy.context.scene.objects.find(obj.name)

we pass only the object index to the driver to identify it and access its properties.

import bpy

def change_image(n,min,max,index):
    obj = bpy.context.scene.objects[index]
    val = int(n*10)
    if (min <= val <= max):
        filePath = obj["file"] % val
        bpy.data.images[obj["img"]].filepath = filePath

bpy.app.driver_namespace['change_image'] = change_image


How can I make a tube with a certain shape? I have the following shape in the 3 dimensions:

As I'm not sure how to properly express what I want to do, I'll try to do it in 3 (among 6) different ways that I can imagine it. I want to:

make a torus that will have the above shape
have the shape act as a skeleton for a torus
give volume to the shape (turning it into a "tube")

What I have found until now is this answer: How do you make a torus 'telescope' open?

Using that solution I end up with something like this:

It covers me almost perfectly except one minor detail. The object isn't a mesh that contains vertices/edges/faces. How can I make that happen?
Increasing the resolution below "Bevel" in Geometry, adds more detail obviously..but it is still treated as one, whole object and not as separate v/e/f.

In object mode press Alt+C to convert from curve to mesh


Create image effect in Cycles as FNAF / video noise effect How can I create a camera effect as in FNAF?

Notice the white lines, not the user interface. Also, the black illumination, but explaining it separately.

I'd do this effect in compositing by adding a noise texture. Create a noise texture and play with the settings until you have something you like. You probably will want to stretch it in X direction a good amount, otherwise you'll get boring TV noise...

To mix the texture with the render output, you could add them together. Also try a color mix node between the render and white with the (inverted) noise image as factor.

If compositing doesn't work, put the texture on a plane and attach it in front of the camera. In the material of that plane, the black of the texture should get transparent.

To animate it, animate either the seed or the UV coordinates.

EDIT

Just tried it out myself by compositing this effect over the default cube. Some tips:

I used a clouds texture for the noise. The default noise texture didn't want to get scaled properly
Adding the effect was not such a good idea. Mix works better
The clouds texture needs a color ramp to increase the contrast
Blurring the texture (after the coloramp) can improve the result
You should use multiple effect textures with different size and strength or use the one texture multiple times
Animation can be done by creating an offset vector with the time input and some love
If you use multiple textures, animate them in different directions

ANOTHER EDIT

Here my node setup with the result in the backdrop:

I used the same texture three times, you can see its settings on the right. The combine RGBA node is just another way to input the scale vector so that you can see its values. Do not use transform/scale nodes instead because this will look bad if you are not scaling down enough. The texture on the bottom is the basic noise, it will also work alone without the others. The texture in the middle adds some really small noise. It is only stretched by factor 3. The noise setup at the top gives some of the bigger artifacts.

To animate it, put an RGBA node into the texture offset and animate it as usual.


Blender 2.8 translate vertex using scaling In previous versions of Blender I could translate vertices to the same coordinate as the cursor by enabling cursor transform orientation, selecting vertex to move, pressing S to scale, type the coordinate I wanted to translate along (X, Y or Z) and typing 0. The vertex would move to the same coordinate of the cursor (zero scale relative to cursor). This feature doesn't seem to work in Blender 2.8, or is there a way to enable this?

Double check this. Scaling in 2.8x works similar to 2.7x:

if you still have problem with it, provide more information and screenshots.


Downloading Blender 2.82 I am trying to download Blender 2.82 but am getting and error. The source file can't be read according to Firefox. It takes forever to get the error message.

\AppData\Local\Temp\SgY4o2hI.msi.part could not be saved, because the source file could not be read.

Try again later, or contact the server administrator.

this is the error

I got it to work today after restarting my PC. I don't know why it was being an issue, probably something to do with my poor satellite connection.


How to restore default theme presets? I accidentally deleted the theme presets in user preferences and I would like to be able to restore them. How can I do this?


How do I add particles around objects In this picture, I modelled a very (bad) gravestone. What I want is described below. Would really appreciate it if you could explain it simply. I'm new to blender. Also, is there an addon for it?

I want weeds only around the stone slab not inside it (which happens if I use vertex groups

This is the best reference image I could find that resembles what I want. Notice how the grass clumps around the roadsign.

Sometimes getting out of a box is the easiest solution. I would create new object to emit those particles ;)


Custom Nodes: How to validate a link? I'm developing an add-on that uses a custom node tree. I want to be able to set a link between nodes as being valid or not:

NodeLink has the property is_valid which controls also how it's drawn (as pictured above). I want to use this value, but something keeps changing it to True any time the node tree updates.

Node's have the insert_link(link) method which you can override. It seems to be the first thing called when a new link is made. This would be an ideal time to validate the link and set the property.

After insert_link(link) returns, the NodeTree.update() method is called on the parent NodeTree which you can also override. What ever value you assigned to NodeLink.is_valid is still the same at this point.

I don't think any other functions are called inside the custom tree after that? But once the UI updates the NodeLink.is_valid value has returned to being True regardless of what it was set to.

The same thing happens if you change the value from the python console. It will draw in the red color and be False if you check the value. But as soon as any new link or update is made to the tree, it goes back to being True again.

Something else must be determining if a link is valid each time it updates? But I cannot find anything in the documentation that says what this is or how to interact with it??? But, it seems like this should be something that can be done given there is a built-in value for it and the UI checks that value when drawing it...

So how do you validate links in a custom node tree?

# First function called in custom tree when a link is made
def Node.insert_link(link):
    # Validate the link
    link.is_valid = False

# Called after insert_link is finished
def NodeTree.update():
    # Link valid value is still set from above
    link.is_valid
    False

# After update link valid value has been set to True
link.is_valid
True

I'm currently working around it with a custom bool property, which essentially just duplicates the existing property. Which works fine for preventing problems with invalid connections, but the state of the link isn't displayed in the UI.

I suppose an acceptable solution would be a way of making the link draw in red using my custom property. It just seems really silly when the property already exists and does the thing I want, but something keeps on changing it on me.

ntree_validate_links(bNodeTree *ntree) in the C code is the thing that causes it to change and is called as essentially the last thing when updating a node tree. It does three things, first is sets the flag to valid, second it checks for a cyclic link and will set the flag to invalid if found. Lastly it checks for ntree->typeinfo->validate_link which I'm assuming is a function pointer and calls that to set the flag.

I'm not seeing anything in the RNA node stuff to interact with it though.

I'm not sure this is what you're looking for.

In Sverchok we add a property to the socket class, called 'other', which returns the socket instance of the other socket, and even iterates back through "ReRoute" nodes.

@property
def other(self):
    return get_other_socket(self)

This lets us do a simple test when appropriate.

if not socket.is_output:
    if not (socket.bl_idname == socket.other.bl_idname):
        ... # handle the mismatch in socket types

You figure the logic out for input sockets vs output sockets. Some node systems (Sverchok included) don't allow a node to accept multiple links on an input socket -- By design.

modified from sverchok/data_structure.py

def get_other_socket(socket):
    """
    Get next real upstream socket.
    Will return None if there isn't a another socket connect
    so no need to check socket.links
    """
    if not socket.is_linked:
        return None
    if not socket.is_output:
        other = socket.links[0].from_socket
    else:
        other = socket.links[0].to_socket

    if other.node.bl_idname == 'NodeReroute':
        if not socket.is_output:
            return get_other_socket(other.node.inputs[0])
        else:
            return get_other_socket(other.node.outputs[0])
    else:
        return other


Why is the mirror making secondary lines? Why is the mirror modifier making secondary lines and how can i make this not happen its on origin to geometry bounds center the lines are only there when i have the mirror modifier on with x axis location of x is set to zero and i have no shape keys

You need to provided a better image of your mesh that covers more detail. But my guess at this point is that your mesh is off center and the current transformation has not been applied.


how to make an addon with custom driver function In my addon everything is working fine.... other than

bpy.app.driver_namespace["Driver"] = driver

It works if I enable the addon on starting blender, but once I save user preferences, then it seems to not run that line of code but everything else works fine, as far as I can tell

I have tried putting it in classes and in the register function but nothing works

Use a persistent load_post handler to register your drivers to the driver namespace.

import bpy
from bpy.app.handlers import persistent
from bpy.app import driver_namespace as dns

def driver(x):
    return x

@persistent
def load_handler(dummy):
    print("Load Handler:", bpy.data.filepath)
    #dns = bpy.app.driver_namespace
    # register your drivers
    dns["xdriver"] = driver

def register():
    load_handler(None)
    bpy.app.handlers.load_post.append(load_handler)

def unregister():
    bpy.app.handlers.load_post.remove(load_handler)

if __name__ == "__main__":
    register()


How to move using precision at a random angle? In my screenshot I rotate the whole object in edit mode (any random angle so the axis won't line up with the grid). I want to add a segment or edge (blue line in the screeshot). I can do this with subdivide, but how to precisely make it exactly 1 unit from the red edge? What is the fastest workflow? is there anyway in Blender I can hava a custom construction plane?

You can select a face, turn the transform orientation to "normal", then click the plus button: this will create a new set of trasform orientation that you can use to manipulate your vertices, edges and faces along the three normal vectors of the first face you selected.

Then in the overlays section you can activate the measurement function, to get infos of edges lenghts and faces areas.


How to make a crystal ball with particles inside in cycles i'm new on 3D modeling and Blender, I'm self-teaching the 3D design and I can't find how to make a crystal ball with particles inside that reflect lights incoming in the ball.

I would like to create something like that:

Any advise to make it?

I figured some of it

Here what i got so far


How to turn medical scans into models in Blender? This is not directly a Blender question, as it could be solved otherwise, but I'd like to see whether experienced users would do this inside blender and how.

Let's assume I had access to various kinds of 3D scans like CT, MRI, OCT, etc. The overall goal is to extract some part from this scan and turn it into a simple and good looking mesh. A very easy example would be to extract the skeleton from a CT scan. In this case I could

do a bone segmentation in the CT volume because this works reasonably well
use the binarized volume data to calculate the surface mesh of the skeleton
import and simplify the mesh in Blender

Other problems are harder to tackle because tissue or organs might not be easily separate-able from its surrounding with image processing. However, an expert could easily do the segmentation manually or semi-automatic layer by layer.

Question: For these two problems, is there a preferred way about what should be done inside Blender and what not? Are there good tutorials about it?

The second problem is especially interesting since one could trace the structure layer by layer inside Blender, extruding each layer afterwards. However, this could be more tedious than simply doing the segmentation in the images and calculating the mesh like in the first case with e.g. marching cubes/tetrahedrons.

Note: I have see the related questions here, here and here but unfortunately they are only related and don't discuss how to turn a scan into a simple mesh.

The overall goal is to extract some part from this scan and turn it into a simple and good looking mesh

It depends what is a good looking mesh according to you:
a mesh that that a same shape as the medical scan or a mesh with a good topology.

For a blender user, a good topology is very important is it will influence further modeling ( such as smooth of subsurf), UV mapping, Rendering time etc..

  •import and simplify the mesh in Blender

What do you mean by simplify? Change the topology in order to have fewer points? or make the mesh to only have quads?

  Other problems are harder to tackle because tissue or organs might not be easily separate-able

In the CT scan, for each point, do you have some kind of additional information, such as tissue density, that would help to separete organs?

  Question: For these two problems, is there a preferred way about what should be done inside Blender and what not? Are there good tutorials about it?

One could see 2 options:

Export the CT scan data in a format that can be import by blender.
Convert the CT data, in the some data point file (with a defined referential point, 3D coordinates, tissue density) like .csv and then use a python scrypt to import it into blender.


Import object without bpy.ops.wm.link_append Is it possible to import an object from a library file through Python without using bpy.ops.wm.link_append? I want an object to appear in bpy.data.objects without updating current scene.

Since Blender 2.72, there are two separate operators:

bpy.ops.wm.link()
bpy.ops.wm.append()

Apart from operators, there's also a lower-level API to import datablocks (selectively) from .blends: bpy.data.libraries.load()

The docs include a few examples how you can use this function.


How to add a border to a single videoclip I just started to use blender because Camtasia is crashing like ***** al the time and Techsmith doesn't seem to care.
I have a few thing tackled like adding text, resizing and i can make things move in and out by using keyframes.

The one thing i cant find any info on is borders, how can i add a border to a single videoclip?
With an image overlay i could emulate this but the problem is that i want the border on a single video clip, the video clip in question is rotated and moving around the screen by using keyframes.

In Camtasia you can just enable a border choose a thickness like 6px and choose a color, this wil add a 4sided border to the videoclip/picture.

I am thinking of 2 (untested) solutions richt now but they are time consuming.

Create a new scene, add the videoclip, add an image overlay (border) and add the scene to the mainscene.
Create a new project, add the videoclip, add an image overlay (border) render the project and import the rendered videoclip in the mainproject.

I hope someone can help me with this.

Blender can do all of those things but it takes a little bit of extra effort to set up. There is no "outline" tool, so you make it with a mask.

Create a mask in the UV/Image editor (render a frame from the video as a guide f-12), make sure that it is 'reversed' by clicking the Invert Mask button in the mask properties panel

Shift - A Add a "Color" effect strip above the video you want to highlight and apply a strip modifier in it's Strip Properties panel N key. Set the color strip's "Blend" type to Alpha Over or Over Drop.

To move them around the screen, (1) select both strips and combine them as a Metastrip ctrl-G. (2) Select the metastrip and add a Transform effect strip Shift-A. Select this new effect strip and change its "Blend" type to Alpha over or Over Drop the image or video (3) placed at the bottom of your stack. Use the properties panel to move and keyframe any animation.


Edge won't go away, no matter what I try, and it can't be selected theres a loose edge in my blend file and i tried delete loose, clean up, remove doubles, EVERYTHING. i worked hard on this model and i can't let it go to waste. anyone help?

The edge is a separate object from the rest of the mesh; it appears orange because it was also selected when you entered edit-mode. Tab into object mode, deselect the main object so that the only object selected is the mystery edge, and delete. (X or Delete)


Rigify - How do I change 'Bend Rotation Axis' parameter using Python? I’m trying to change this 'Bend Rotation Axis' parameter using Python: Bone Tab > Rigify Type > Bend Rotation Axis. Unfortunately, the output of the Info window isn’t shedding much light on this:

I have tried this:
 bpy.data.objects['metarig'].pose.bones['thumb.01.L'].primary_rotation_axis = 'X'

... but I’m getting the following error:

AttributeError: 'PoseBone' object has no attribute 'primary_rotation_axis'

When I hover over the Bend rotation axis dropdown, I get the following tooltip:

Q: How do I access the Rigify parameters class and assign my values?

Figured it out:

 bpy.data.objects['metarig'].pose.bones['thumb.01.L'].rigify_parameters.roll_alignment = 'manual'
 bpy.data.objects['metarig'].pose.bones['thumb.01.L'].rigify_parameters.copy_rotation_axes = [True, False, False]


Sequencing Animations in Animation Nodes I'm working on a complex animation with many sequential elements. Animations nodes I've found animation nodes excellent for creating animations, but that it doesn't really have a way to organize the timing of these animations. Below I describe the issue in more detail.

Some approaches that I have taken:

Creating a "Master Delay" Custom Object property: This master delay value is added to existing delay nodes. However, I find this to be a pretty inefficient
and cumbersome method because it means adding an Attribute Input and
Float Math node for each existing delay node. Also, it becomes difficult
to keep track of which animations I want to be affected by the master delay. Say I wanted multiple master delay properties for several "groups" of sequential animations. Then if I wanted to offset multiple master delays, I would have to add in yet more nodes to delay the master delays.
Using Ojbect Transform Inputs with Parented structure: Blender certainly has a means of nesting values via constraints and parenting. We could potentially create a parented delay value system by parenting several empties to a master empty. However, I find this method also means adding lots of nodes to my trees, and means we have to come up with a system for visualizing the values of those empties' locations.
Bake Animations: While this lets us move keyframes in the dopesheet/graph editor, we lose control over our node network parameters. Not interested.

I'm wondering if anyone has a different approach to this issue. Animation nodes is a very powerful tool, but without the ability to structure the timing of nodes tree, it's extremely arduous for use in longer projects where the order of the animation is important.

Animation Nodes already provide such nesting functionality in the Animate nodes, and you can similarly implement an equivalent functionality if you choose not to use the native Animate nodes.

An Animate node interpolates between two values for a certain duration. For instance, if the start value was 0, the end value was 5, and the duration was 20, then the output will gradually increase from 0 based on the chosen interpolation for 20 frames where it reaches 5 at the 20th frame.

But what about the frame at which the animation starts, how do we define that? Well, Animation Nodes always starts the animation at frame zero. However, the frame/time is exposed as an input in the Animate node, so what we can do is edit this input frame/time such that it becomes zero at the frame we want the animation to start at. This is easily done by subtracting the target starting frame $f_t$ from the scene or master frame $f_m$, because when the master frame becomes equal to the target frame our equation returns zero  $f_m-f_t = 0$. This is what the Delay node does, it simply subtracts the input, nothing more, nothing less.

Now, the Animate node provides a Time output. This output is the input time minus the duration. Think about that for a second. It means that if the output time of an Animate node $A$ is used as the input time of another Animate node $B$, the $B$ animation will start as soon as the $A$ animation ends. Now, if I delay (by subtracting) the output time of the node $A$ by 5 frames and use it as the input time of the node $B$, then the $B$ animation will start after the $A$ animation ends by 5 frames. And so on.

So, to implement a sequence of animations, use a chain of Animate nodes where the input time of each node is the output time of the previous with a possible delay (With the first node having the master time as its input, also with a possible delay). Want to add an animation at the start of the sequence, no problem, just put this node first. So the node tree should look like this:


Cycles | Boolean modifier - Color Issue I'm making a Minecraft character and for the face I made holes with the boolean modifier; inside the head everything is grey but I want to have the colors of the front side of the head. I want to be able to modify the cubes which cut the holes so I don't want to apply the modifier.

The Boolean mod will place whatever materials are on the mesh used to modify the object provided that they are also included in the modified object (i.e. the big cube).  Only colors that are in the big cube will be received from the modifying mesh (the little cube).  You can see a dark green on the underside of the little cube but it is not applied to the cavity because the big cube does not contain that material.

So you must make your modifier mesh cube exactly the way you want your colors to appear in the head cavities.


Cannot Open start avi movie file I am new to Blender.
I have a new Macbook Pro 2018 with the highest upgrades in memory, speed and all. Running newest os.

I watch a video about the fox logo from Matt Hoeker, and followed it to the letter. Everything goes exactly like the video until I hit render animation, and it goes to a new page as if it is going to render it and then within seconds I get the message at the top that reads, "Cannot open or start avi movie file". I checked the exchange where others have had this problem, but I do not see any solutions. I'm trying to do something cool for my school, but 2 hours of failing has me desperate for help.
All the best,
Mike

Mac computers do not play avi files unless you use another video player to see it.

I recommend you to render your movie in mp4 format.

See this related answer:

MP4 video settings


How to add a custom panel to particle properties? I'm trying to add a new panel to show up in the particles section of the Properties Editor.

class CudaParticlePanel(bpy.types.Panel):
    bl_idname = "CudaParticle_Panel"
    bl_label = "CudaParticle"
    bl_category = "SYSTEM"
    bl_space_type = 'PROPERTIES'
    bl_region_type = 'WINDOW'
    bl_context = "PARTICLES"

    def draw(self, context):
        layout = self.layout
        layout.label(text= "CudaParticals Properties:")
        self.layout.label(text="CudaParticle")

I don't get any errors or warnings when running the code but my panel does not show up. Can anyone please explain different locations of the UI and how to put a panel there?

You need to register the class to use it.

Also bl_context = "PARTICLES" should be replaced by bl_context = "particle"

Here's the complete script

import bpy

class CudaParticlePanel(bpy.types.Panel):
    bl_idname = "CudaParticle_Panel"
    bl_label = "CudaParticle"
    bl_category = "SYSTEM"
    bl_space_type = 'PROPERTIES'
    bl_region_type = 'WINDOW'
    bl_context = "particle"

    def draw(self, context):
        layout = self.layout
        layout.label(text= "CudaParticals Properties:")
        self.layout.label(text="CudaParticle")

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

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

if __name__ == "__main__":
    register()


Mirror Multiple object or parent and sub meshes Might be a funny question, but how can I mirror multiple objects? I made one side of the headphone with multiple meshes and parent them together. Is there a way I can mirror then easily? Or the only way is to mirror then to an Empty axis object one by one?

Doing ctrl+J messes with the modifiers of each object.

You can transfer Modifier or "Link" them from one object to others.
By selecting multiple objects and pressing CTRL+L you get a menu that looks somewhat like this:

By clicking on modifiers, the modifiers of the last selected Object (your active Object) get copied over to the other selected objects. That way you can Setup one Object the way you want and just transfer the modifier to the other objects.


Creating volumetricaly layered materials in Cycles Recently, I've been wanting to create a model with a particular artstyle. It involves the model having glowing parts basically identical to the buttons from this question. However, the particular style I want to go for involves the parts being scattered about, irregular and generally a massive pain in the behind if I have to manually go in and add a separate emitter mesh to each one of them (which is what was used in order to create that effect in the original question).

Therefore, my question: is it possible to create a purely material-based setup where the object to which the material is given appears to have one material layered on top of another (e.g. translucent with emission behind it or glossy coated in a layer of glass)? I would imagine it MIGHT be possible using something like the Ray Length component of the Light Path input, but my attempts at it weren't super successful due to my general lack of experience with complex material node setups.

Any help would be appreciated.

If you mean what I think you mean, then yes it is possible.

Is this what you mean? It is one object, but there are different materials in different places.

This is the node setup:

The way this works is I separate the object into its X, Y, and Z coordinates. I then select how much of these coordinates I would like to be one material (In this case emission, shown by the white in the colour ramp nodes. This allows layers of different materials within the volume.

If you require these layers of materials to be place at random points, you can just plug in the red component from a noise node into the factor for the mix node as shown below:

I have also passed it through a brightness and contrast node to emphasize the border between the two materials.

Here is the result:

You can achieve really interesting results if you use different types of textures:

Node setup:

Another interesting result I came up with:

Hope this helps you :)

EDIT:

Here is the technique applied for a layered material:

Here is the node setup:

To achieve this layered effect simply change the color ramp. the black bars on each side of the color ramps indicate the thickness of the outer layer. However, this only works with volumetric materials like emission, volume scatter and volume absorption. To layer multiple surface materials they can simply be mixed/added. This will however not work with visible thickness as they are surface shaders and as such only appear on the surface and not in the volume.

That being said, the glass, refraction and transparent shaders can yield some interesting results with the fresnel node.

E.g: Layered glass:

Node setup:

The color ramp may look completely white but it is actually 1.1 and 1.45, set to constant.

However, a see through surface shader may be used together with a volumetric to achieve a different type of layered effect.

Volume scatter in glass:

Emission in translucent:

Generic node setup for volumetric within surface:

The volumetric can be replaced with any of the volumetric shaders shown above.

Hope all this additional info helps :D

EDIT 2:

Just ended up making the 'button' with this technique, thought I'd put it here:


Can I export Quick Favorites from 2.82 to 2.83 With all the back and forth between 2.82 and 2.83 daily releases, I was wondering if there was a way to export your 2.82 quick favorites menus to use them in the 2.83 beta?

Quick Favorites are part of user preferences and saved along them in the preferences file.

Copying this file from one installation to another should bring Quick Favorites with it.

Beware that this file saves most Blender settings along with it, so overwriting with an older one may unintentionally change other preferences you may have already configured. It may also cause unforeseen issues when things change between Blender versions, so use with caution and take care to make backups beforehand.

This file is usually saved under C:\Users\<UserName>\AppData\Roaming\Blender Foundation\Blender\<VersionNumber>\config for Windows OS. After installing a new version you should have two different <VersionNumber>, so copy it from the relevant one to the new one.


How to make eyes that fit the mesh I am try to make an anthro fox but the eyes never seem to fit the sockets. Is there any way to model the eyes to fit or do I need to adjust the sockets themselves?

Look at pictures of a real fox!
You have to model the tear duct.

Same goes for other eyes, by the way. The Spheres won't fit unless you add a tear duct.


How to make softer, more natural lighting? I'm trying to recreate this image:

This is what I have so far:

The lighting doesn't look as soft and natural as the first picture. Lighting has always been that hurdle I can't jump across, but now it's starting to become more of an issue. Right now I am just using two emission planes for the light source.

https://drive.google.com/file/d/0BzgDIjhDOu6EbGVhZEtHQ2d1V3M/view?usp=sharing

The reference image is a studio lit still life. There are two "Soft Boxes" camera left and a spot light on the background. Probably a black card camera right to prevent light from filling in the shadows. It appears a relatively long lens was used to compress the scene and emphasize the shallow depth of field.

Here is how I recreated the scene in Blender with a camera focal length of 150mm.


Modeling with reference image I want to create a model of a human using "Blue Prints" as reference.So when i start modeling the form of the Head i start with the Front view of the face and match the points to positions where i think they are fine.When i switch the view port to the left/right side , to give the head like the 3d form and shape the points look good on the side but back in front view they look like they're on other positions so i ajust them in front view , switch to side and yet again they're on other positions.i hope my question is understandable ^^.do you guys have any advise ? i'm a beginner , i know the basic stuff but have problems with that.

Good Reference Images and Alignment

The biggest problem about modeling 3D models from 2D reference images is the alignment of your reference images - especially when you start modeling faces.

My advice for a beginner is to start with a "best as possible" aligned reference image. As you can see in the set of images below (from www.3d.sk) I used lines to align the prominent facial features, mainly the eyes, the nose and the mouth (The alignment is still not perfect for various reasons regarding the reference images).

Modeling Process

Although some tutorials on the internet mention that it's best to start with a base mesh for the head, I strongly suggest that you start with a simple plane at the eyes and a mirror modifier, then model the base shape of the face in front view with the least amount of vertices possible. Switch then to side view and start aligning the outer verts to the side reference.

During the modeling process you are then going to add loop cuts and constantly switch between front and side view to align the vertices.

The best and most in-depth tutorial for beginners on this topic is this one made by Joshua Alger.

Oh, and also do not expect to get a perfectly recognizable 3D representation of the reference images the first time you do this. It'll take some time, but with enough determination you will get there.


Fake reflections in Cycles Is it possible to fake reflections per object in Cycles? If so, how? (I don't mean one image to appear as background and another to appear in all reflections). I mean using an image on the object mapped to reflection coordinates.

Scenario: I am using an Environment texture in the world shader settings. I have multiple objects each with reflective surfaces, one of which is using the Glass shader, I'd like the glass to reflect as it normally does with the addition of another image. To be able to blend the actual scene (objects+environment maps) with an entirely different environment reflection that isn't part of the scene.

Expanding on brecht's answer, here is a simple node setup:

A glossy node is used instead of an Emission node to get the "real" reflections in addition to the image. To do this with a Glass node, you will have to separate the glossy and refraction.


import 3ds files in Blender 2.80 I see there is no option for importing 3ds files in the File -> Import menu in Blender 2.80.

Does this mean importing 3ds files will no longer be supported in Blender?

The best solution I've seen so far is to open ver. 2.79, import the 3ds file in that, then copy and paste the entire screen to ver. 2.8.  You can then save to a .blend or .dae or .obj file from that.


Blender dev build question On https://builder.blender.org/download/ there are 2 version available for download:

non-stable build and
Experimental Build Branch by VS 2015 .

What does this mean and what are the differences ?

A build considered as not stable is a version in developpement. They have new functionnalities/changes that still need to be tested, or contains known bug that will be fixed before official releases.

An Experimental Build Branch, as said in the description are build with another compiler than the "usual" one. They should be stable (release 2.78) but you never now what can appen using a compiler that wasn't used for tests.

If you have no reason to use one of them, use the official release


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

You didn't pack the texture with the file so I wasn't able to check where they were assigned to...

...anyway, by unchecking the UV local view box, you should be able to Unwrap and see the faces.

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


Where does Blender "connect" to NVIDIA drivers? Using a NVIDIA GeForce 1060 with Blender 2.8 worked fine until upgrading recently to Debian 10 and Blender 2.9, but now Blender 2.9 does not recognize my NVIDIA GPU in Preferences -> System -> Cycles Render Devices.
Troubleshooting online says to "update drivers" [ cite1, cite2, cite3, cite4 ], so I updated the drivers, to no avail.
Steps taken:

I installed NVIDIA drivers manually following this tutorial from linuxconfig.com
Purged everything, next I tried this tutorial which helped previously when using Debian9
Purged everything, next I tried installing NVIDIA drivers from Debian's Manual
Purged everything, next I tried installing the "most recent" version from NVIDIA's website following this tutorial

All of these were able to get NVIDIA installed and CUDA working fine, no issues with nvidia-smi, but Blender would not recognize a GPU.
Thinking it a Blender issue, I removed Blender 2.92 and tried using Blender versions 2.91, 2.90, 2.83, and 2.79, none of them pick up my GPU anymore.
Thinking it a Debian issue, I did a fresh install of the OS system and installed all software, drivers, and headers, fresh.. to no avail.
At wits' end, curious to know if there's a way to manually "point" Blender's Cycle Render Devices to my GPU, and how to do that, if it's even possible. If not, what steps are left to be taken when the only advice is "update your headers" and the headers have been updated a dozen different times?

It was a CUDA issue.  Blender needs nvidia-cuda-toolkit to find & connect your GPU. The Debian Wiki directions for installing CUDA didn't work
for me, so I needed to download the most recent CUDA version and manually install it.
To start from scratch:

Uninstall NVIDIA & CUDA:
$ apt purge nvidia*
$ apt purge cuda*
Download proper NVIDIA drivers
Download proper CUDA toolkit for your system (I used deb[local])
Before installing drivers, you must obtain the proper kernel headers for the NVIDIA driver to build with.From Debian Wiki:
$ apt install -t buster-backports linux-headers-amd64
$ apt install -t buster-backports linux-image-amd64  #installs the kernel from backports to match
Now it gets tricky: Disable the default nouveau driver
$ echo blacklist nouveau > /etc/modprobe.d/blacklist-nvidia-nouveau.conf
Reboot to multi-user runlevel. #This will disable the GUI user after reboot
$ systemctl set-default multi-user.target
$ systemctl reboot

NOTE WELL: When you restart your computer, your screen won't work. Everything you do will be from the command line.

From command line (or Safe Mode), navigate to directory with NVIDIA run file:
$ bash NVIDIA-Linux-x86_64-your.version#.run
During installation, you'll be asked questions, say YES to everything and install NVIDIA driver. After reboot, SCREEN SHOULD START UP USING YOUR GRAPHICS CARD.
Remind your computer to use the GUI every time it starts up:
$ systemctl set-default graphical.target

NVIDIA is good to go, but Blender still won't recognize your GPU because CUDA needs to be downloaded with nvidia-cuda-toolkit.

Download/Install CUDA Debian Installer from CUDA docs remembering to modify the PATH and LD_LIBRARY_PATH variables.
Make sure FILEPATH has been changed correctly.
From Debian Wiki, install nvidia-cuda-toolkit picking up any missing pieces:
$ apt install nvidia-cuda-dev nvidia-cuda-toolkit
Update everything with $ sudo apt update
Reboot computer: $ systemctl reboot
Open Blender, check Edit --> Preferences --> System, and GPU's alive and well


blender soft body not updating after obstacle moved I have a soft body plane, and want to delay it's movement. To do this, I added a plane, that stops the soft body. the problem is, when the obstacle moves, the soft body stays in place. does anyone know how to get it to move when the obstacle is gone?

Make sure your plane (that stops the soft body) has collision turn on. Then also make it a rigid body (type "passive") and animated:

Now you can animate the plane's movement the way you want. The soft body ball (in my case) will interact with it.


Accidently pressed Y on mesh Hello Blender community.
I was working on something when I accidently pressed Y with a part of mesh selected, and now that part is not with the mesh anymore and can move around freely. I didn't notice this when working on it so can't do Ctrl+Z anymore.
Is there any way to.. attach the parts again?

If You didn't move that part yet, select all in edit mode, press W and choose Remove Doubles.


Wrong textures appear in rendered view So, I have tried a tutorial about building a medieval house and everything worked quite okay for me until I came to the point of applying textures. I didn't follow the tutorial there because i remembered doing it differently a few years ago. I got into it again quite well and applied almost all the textures to the faces BUT... in my 3D view it looks like this, well, like it is supposed to look. Somehow.

And then when I look at it in rendered view, it shows that somehow only the stonewall texture got applied to some of the faces.

I tried activating the wooden frame around the house and apply the texture again but the suddenly all the textured faces from the second image were covered with the wooden texture.
I put a new material, put a new texture, clicked on assign in the material window and everything, I just can't get it. Also, what is bothering me is that i can't seem to apply any texture to the main structure (the house itself). I would be glad if someone could to help me.

In 3D material view:
The image corresponds to the preview but what is bothering me is that the whole structure is affected and i can't obviously have a different material for different parts of the structure. AND the UV editor shows the "right" texture for the selected face.

In rendered view:
It still looks the same like in the image above in my original question.

Texture view:
Also still the same.

So, what did i do wrong?

By the way, here is the file:

Found the problem!

Some faces overlap and causes some rendering problems. Go into Edit Mode and move some of the faces away from its overlapping part.

Note: Since you didn't give me a texture to work with, I simply used my own...

Another solution: Remove Doubles (Press "w"), but this will make you have to unwrap some faces again.

Nice house by the way!

Another problem: The overlapping faces that are causing render problems isn't properly unwrapped:

I'm assuming you know how to unwrap, so go ahead and do that!

P.S: Select everything in Edit Mode and press ctrl + n. This will recalculate the normals and make you feel more organised ;)

Happy Blending!