text:
Dynamic Enum Previews
I want to add a few options to this python template which I found inside Blender-ui_previews_dynamic_enum.py
Here is the code:
import os
import bpy

def enum_previews_from_directory_items(self, context):
    """EnumProperty callback"""
    enum_items = []

    if context is None:
        return enum_items

    wm = context.window_manager
    directory = wm.my_previews_dir

    # Get the preview collection (defined in register func).
    pcoll = preview_collections["main"]

    if directory == pcoll.my_previews_dir:
        return pcoll.my_previews

    print("Scanning directory: %s" % directory)

    if directory and os.path.exists(directory):
        # Scan the directory for png files
        image_paths = []
        for fn in os.listdir(directory):
            if fn.lower().endswith(".png"):
                image_paths.append(fn)

        for i, name in enumerate(image_paths):
            # generates a thumbnail preview for a file.
            filepath = os.path.join(directory, name)
            thumb = pcoll.load(filepath, filepath, 'IMAGE')
            enum_items.append((name, name, "", thumb.icon_id, i))

    pcoll.my_previews = enum_items
    pcoll.my_previews_dir = directory
    return pcoll.my_previews

class PreviewsExamplePanel(bpy.types.Panel):
    """Creates a Panel in the Object properties window"""
    bl_label = "Previews Example Panel"
    bl_idname = "OBJECT_PT_previews"
    bl_space_type = 'PROPERTIES'
    bl_region_type = 'WINDOW'
    bl_context = "object"

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

        row = layout.row()
        row.prop(wm, "my_previews_dir")

        row = layout.row()
        row.template_icon_view(wm, "my_previews")

        row = layout.row()
        row.prop(wm, "my_previews")

# We can store multiple preview collections here,
# however in this example we only store "main"
preview_collections = {}

def register():
    from bpy.types import WindowManager
    from bpy.props import (
            StringProperty,
            EnumProperty,
            )

    WindowManager.my_previews_dir = StringProperty(
            name="Folder Path",
            subtype='DIR_PATH',
            default=""
            )

    WindowManager.my_previews = EnumProperty(
            items=enum_previews_from_directory_items,
            )

    # Note that preview collections returned by bpy.utils.previews
    # are regular Python objects - you can use them to store custom data.
    #
    # This is especially useful here, since:
    # - It avoids us regenerating the whole enum over and over.
    # - It can store enum_items' strings
    #   (remember you have to keep those strings somewhere in py,
    #   else they get freed and Blender references invalid memory!).
    import bpy.utils.previews
    pcoll = bpy.utils.previews.new()
    pcoll.my_previews_dir = ""
    pcoll.my_previews = ()

    preview_collections["main"] = pcoll

    bpy.utils.register_class(PreviewsExamplePanel)

def unregister():
    from bpy.types import WindowManager

    del WindowManager.my_previews

    for pcoll in preview_collections.values():
        bpy.utils.previews.remove(pcoll)
    preview_collections.clear()

    bpy.utils.unregister_class(PreviewsExamplePanel)

if __name__ == "__main__":
    register()

This code will scan and use the png files from the directory and create the thumbnails of that.
Is there a way to specify the items before, with thumbnails, and on choosing a certain option from that menu, a change in the code takes place.....

Try using update methods.  Changing the dir would be the time to populate the list, changing the enum ... run some other code.  A lot of the code in the items callback can then be removed.
import os
import bpy

preview_collections = {}

def enum_previews_from_directory_items(self, context):
    pcoll = preview_collections.get("main")
    if not pcoll:
        return []

    if self.my_previews_dir == "": # use better default
        # put some code in here to populate default list
        print("MAKE A NEW THUMB LIST HERE")
        newlist = []
        '''
        # a list of items with name, filepath to image, and unique i

        thumb = pcoll.load(filepath, filepath, 'IMAGE')
        item = (name, name, "", thumb.icon_id, i)
        newlist.append(item)
        '''
        return newlist

    return pcoll.my_previews

class PreviewsExamplePanel(bpy.types.Panel):
    """Creates a Panel in the Object properties window"""
    bl_label = "Previews Example Panel"
    bl_idname = "OBJECT_PT_previews"
    bl_space_type = 'PROPERTIES'
    bl_region_type = 'WINDOW'
    bl_context = "object"

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

        row = layout.row()
        row.prop(wm, "my_previews_dir")

        row = layout.row()
        row.template_icon_view(wm, "my_previews")

        row = layout.row()
        row.prop(wm, "my_previews")

# We can store multiple preview collections here,
# however in this example we only store "main"

def preview_dir_update(wm, context):
    print("wm.my_previews_dir = %s" % wm.my_previews_dir)

    """EnumProperty callback"""
    enum_items = []

    wm = context.window_manager
    directory = wm.my_previews_dir

    # Get the preview collection (defined in register func).
    pcoll = preview_collections["main"]

    print("Scanning directory: %s" % directory)

    if directory and os.path.exists(directory):
        # Scan the directory for png files
        image_paths = []
        for fn in os.listdir(directory):
            if fn.lower().endswith(".png"):
                image_paths.append(fn)

        for i, name in enumerate(image_paths):
            # generates a thumbnail preview for a file.
            filepath = os.path.join(directory, name)
            thumb = pcoll.load(filepath, filepath, 'IMAGE')
            enum_items.append((name, name, "", thumb.icon_id, i))

    pcoll.my_previews = enum_items
    pcoll.my_previews_dir = directory

    return None

def preview_enum_update(wm, context):
    print("wm.my_previews = %s" % wm.my_previews)
    return None

def register():
    from bpy.types import WindowManager
    from bpy.props import (
            StringProperty,
            EnumProperty,
            )

    WindowManager.my_previews_dir = StringProperty(
            name="Folder Path",
            subtype='DIR_PATH',
            default="",
            update=preview_dir_update,
            )

    WindowManager.my_previews = EnumProperty(
            items=enum_previews_from_directory_items,
            update=preview_enum_update,
                )

    # Note that preview collections returned by bpy.utils.previews
    # are regular Python objects - you can use them to store custom data.
    #
    # This is especially useful here, since:
    # - It avoids us regenerating the whole enum over and over.
    # - It can store enum_items' strings
    #   (remember you have to keep those strings somewhere in py,
    #   else they get freed and Blender references invalid memory!).
    import bpy.utils.previews

    pcol = preview_collections.setdefault("main", bpy.utils.previews.new())

    bpy.utils.register_class(PreviewsExamplePanel)

def unregister():
    from bpy.types import WindowManager

    del WindowManager.my_previews

    for pcoll in preview_collections.values():
        bpy.utils.previews.remove(pcoll)
    preview_collections.clear()

    bpy.utils.unregister_class(PreviewsExamplePanel)

if __name__ == "__main__":
    register()

You can get fancy with the update methods using the methods outlined here https://blender.stackexchange.com/a/39624/15543

Well, I actually want there to be different options. And, I don't know how to specify those items or options in the enum_previews_from_directory_items(). Each item should have a different thumbnail

Ok, I get it, but how will I check which option is selected by the user.....

preview_enum_update is called when user changes selection.

Thanks for help, I was thinking if it was possible to remove the StringProperty from the Interface, and assign it a specific default value which will never update.... :)


text:
Low poly normals when baking with Cycles
Blender novice here. I'm trying to make some models to use in the Unity3D engine.
I modeled a high poly tube and the low poly counterpart. Now I'd like to bake the normal map from the HP to the LP in order to make it look better. Unfortunately the normal map is horrible, it seems that I somehow tried to bake from the lowpoly to the lowpoly.
I followed this process:

Make the high poly
Make the low poly
Unwrap the low poly
Switch to Cycles renderer and assign a 1024x1024 image
Switch to Normals under Bake
Bake
..
no profit?

This is my high poly and perfectly smooth tube and its counterpart, the low poly and perfectly jagged tube:

This is the result from the bake with "Selected to active":

I may have been missing something during the process. What could be?

Welcome to the site! One of things to check is whether shading was set to Smooth for lowpoly. Other than that, were objects placed in the same place ?

To me, there will be no result in this bake anyway, as the HP is smooth, so you will not obtain a significant normal map. But in the principle, as @MrZak said, the two object need to be at the same place (overlap)

watch out the order in witch you select your two objects for baking, first high poly, then low poly.
This is what is meant by selected to active so that I guess you could bake small other objects as part of your normal map (like stones on the ground) because every object you select is "selected" but the last one in case you noticed has a slightly different selection color and it means 'active'. very usefull

@MrZak yes, the two objects are in the same place. It turned out that I missed the Smooth option! Now everything is nice. Thank you very much!

Firstly, make sure everything is smooth shaded. Then see to it that all normals are facing in the right direction. Or you can simply go to Edit Mode and press Shift+N and normals will align to the face direction. If this does not help you, check your UV and make sure there are no overlapping UVs.

you need to apply smooth shading to the low poly object first then
 bake it again

source: Stack Exchange

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

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

sort: votes


text:
Bad Render. Too much Noise. Low Light
I've been using blender for quite sometime. But I have most my "Disabilities" in the NODE/Material/Lighting area.
I tried most REDUCE NOISE tutorials, tried TOP X Tricks to take out fireflies, but it seems that each case is a case and I cannot achieve approximate results to other people in the same sample size. For example, a person achieves a perfect render a 50 samples. I would have to put 500 samples to try achieve the same result... It's very frustrating.
The lighting inside the "DEN" seems too low, compared to the outside light intensity.
I have a Intel 2600K Processor, G.Skill.Sniper.8GB.1600Mhz RAM, GTX970 G1.Gigabyte Graphics card.
Blender File: http://www.mediafire.com/download/8gd70c8aonbr4ss/BEAR-Radio.blend
(might be missing one or two texture images for the Radio. Just delete that material and it should assume another Radio Material)

use "square samples" in the render panel "sampling section"

Inspecting your file I see there's no lights in your 'DefaultScene' which I presume is the one you are trying to render. Your world node setup is also empty which leads to a black background. General rule of thumb for cycles is: 'Hard to find' light sources generate noise and fireflies. That means avoid very small lamp sizes, light sources hidden behind objects, lots of indirect light from far away or occluded sources.

yes as @DuarteFarrajotaRamos said you need to remake your scene. After that squared samples. And you may obtain that : https://i.gyazo.com/6bd1b655cc58b11960147fcbf6aeb95f.png

@lemon I think you meant "remake your world", not scene. Don't scare the user ;)

Hi guys, thanks for the answers. I'm going to try Duarte's Advice. Altho, what's the point of remaking world? What would that achieve? This is an honest question, since I'm still learning blender.
In my file, I got a CUBE with FAKE sky material that EMITS blue light. That cube is all around the objects and it renders fine, not like yours. Now I have an Issue. When I check Square Samples, Blender renders super slow. Is this for final render only? I also got various blender files, for each Anim that I'm rendering (lots of things tends to crash more). That's why I had no WORLD.

I see, like 100². Wouldn't that be like just putting the X² result from scratch? How is one better from the other? Also, what about the REMAKE SCENE part? I don't really understand what this means.
Thanks all for the answers. I appreaciate them, but I still don't understand some of them. Real noob here :(

Hey @cegaton, I've been using the Squared Samples and I think it's only for Preview/Review of SCENE. I guess it's nothing more that putting the Squared number itself, I would assume. But just quicker. I already been playing around the light intensity alot too and the 100% is not necessary since I'm rendering in 720p. Unless it's better quality to have 720p from scratch and 100% in resolution. Should I use portals in the scene? Considering I have the GROUND object that emits light and CLOSES the object within it's boundaries.

For scenes where the light bounces around a lot (think indoor scenes) you're going to need more samples.  Renders that look good at only 50 samples are probably more open than yours.
That being said, setting max bounces to 0 will get rid of your fireflies, but you will also lose all of the nice bounce lighting.  And at that point you might as well use the blender internal.  My advice is to turn up your samples and go get a cup of coffee.  I wouldn't worry about it.

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


text:
How to export to FBX without baking animations?
I'm using Blender to make animations that I can use in a Monogame/XNA project. I'm trying to export only the keyframes I set, so I can make custom interpolations in Monogame. However, the FBX exporter seems to force the baking of the animation by setting a keyframe at every frame.
If I uncheck "Baked animation" in the exporter (in Blender v2.77), it seems not to export any keyframe at all.

I tried to export in COLLADA as well, which does not bake the animation. However, I really need to use the FBX format as I encountered many other problems in COLLADA.
So here is my question, can we export "unbaked"/raw animation in FBX ?

Unfortunately, no; as far as I know, you can't export unbaked raw animation using the FBX exporter.
According to this post, unchecking Baked Animation disables all animation export, meaning the FBX is created without any animation information at all.  I realize it's tantalizing that perhaps disabling baked animation would have somehow exported keyframed "unbaked" animation, but that's unfortunately not the case with this particular exporter.  Unchecking this option works like an off switch with respect to animation.  Check it and you get baked animation, uncheck it and you get no animation.  :(

In principle one could modify the FBX exporter to do the things being asked. You need some programming knowledge or hire someone to do that for you. Just tweaking the settings won't help in this case.


text:
How do you take baked textures and apply them to a Blender Render/ Game Engine Object
After baking the materials & textures into a .png file and applying that .png file to a blender render, of the EXACT same shape that they were baked from, I have found a weird result. It doesn't apply over the object in the same way that it was baked off the object. It winds up like below.

You probably baked to a different set of uvs.

After reading more about baking, and playing with it some, I found that my error was trying to bake the materials and textures from my cycles render to an image, and then putting that image on a blender render.
To take materials and textures from a cycles render to a blender render or game engine, first you must bake them and apply them over the object in the same file in cycles render. Then you can change to blender render or game engine and go to nodes. Create a new materials node and connect the normal and vector slots between the nodes.

authors: Денис Капустин


text:
Wave Modifier Question
I'm using a wave modifier on a cylinder, but I notice the ends of the cylinder are moving up and down. I'm wanting the ends of the cylinder to be angled as they move instead of just just translating vertically. A demonstration is linked below. Any ideas on how to do that?

As far as I'm concerned, the Wave modifier just moves vertices up and down but doesn't rotate anything because it just works on the single vertices translating them on the z axis depending on their X and Y position.
If you want to make a curved pipe in which the section rotates and not translates, I recommend you to use a curve modifier. You'll need a sinusoidal curve (look here for that) and a curve modifier to apply on the cylinder.

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


text:
Cycles masking object (blocking partial rendering of object)
I am slowly starting to get to grips with Blender basics, but i am currently stuck.
I made a very basic scene using a hdri backround. I would like to create a plane that would "block" the rendering of an object so that it will look like the object is moving around the corner of the building.
The image shows the effect I am trying to create. The sphere on the right needs to be partially hidden by a plane and the background rendered as if there was nothing in front of it.

I looked at this example :
Create invisibility cloak (alpha mask material)
When I enable the Film->Transparent option the plain in front of the sphere does partially block the rendering of the sphere, but then I have no background.
hdri background :

This is the link I meant to put in the description :https://blender.stackexchange.com/questions/7613/create-invisibility-cloak-alpha-mask-material

Your link is broken so I can't see the method you're using.
You can continue like you are and render two images: one of the spheres with transparency on, one of just the background, and then composite them with the Compositor.  I don't believe you can use Render Layers here because the Tranparent option is not render-layer specific.
Or you can do what I did and use a cube to act as the building corner with the Boolean Modifier enabled:

Just make the corner cube invisible and set the following options:

Do you also have a modifier on the building corner cube ? I followed your instructions : set the BuildingCorner not visible and not rendered. Add the boolean modifier to the Pedestrain with difference to the building corner. But it renders just the Pedestrain cube then. What did I miss ?

Oh okay I understand what you where doing. The Pedestrian is subtracted where the two bodies overlap. The pedestrian moves into the Building corner more and more and less is render. Very good and clever idea. I thank you.

You got it!  You're very welcome.


text:
Can I merge multiple materials into one?
I've downloaded and imported to blender 3d models of buildings as one object from open street map. Almost every wall of the buildings imported with it's own material and it will take me ages to texture them seperately. Can I merge some of the materials? The only thing I can come up with is selecting each building on edit mode and assign it each time to the same material, which is also would take me ages to do. Any better idea?

If I got what you ask, you can make material links from all objects to one: all will get last object's material assigned.
It works like this: select all object but one, and then select that last one object too (it will be the "active" object in the selection).
Then use the menu "make links => materials" (or CTRLL and choose "materials". See this image below:

This solution is a bit late but it can help people from future with similar problem.
first, you go to the outliner and pick "Blender File" view.

then open materials, where you will see all the materials this project use.
To use remap materials pick one of those you want to merge, then right-click and pick "remap users". There, under "new ID" pick your target material. Then you can select all the materials you want to merge and just click "OK", it remembers last operation.
Done! Now all objects that were using extra materials use the one you chose. You can delete unused materials and live happily ever after.

authors: อนุพงศ์ วิชาคำ


text:
loop works only for 4 frames any idea why?
I'm trying to use scripting to create jumpy cone for fire purpose, and the loop works only for 4 frames, any idea why? Thanks in advance
import bpy
import random

for object in bpy.data.objects:

    bpy.ops.object.select_all(action = 'DESELECT')

    string1 = object.name

    for o in string1:

    if (string1.find("Cone",0)!=(-1)):

        object.select = True

        c = 2

        a = random.randrange(10,30)

        b = random.randrange(3,6)

        a /= b

        # make each object that string1 find, "ACTIVE"
        bpy.context.scene.objects.active = bpy.data.objects[object.name]

        object.scale.z = a

        bpy.context.scene.frame_current = c

        bpy.ops.anim.keyframe_insert_menu(type='Scaling')

        c += 1

"Cone" has 4 letters.  for o in "Cone" will give values of o of "C", "o", "n", "e"  Added an answer with what I think is the result you are after.  Or there was only 4 objects in your bpy.data, hard to tell as there is a syntax error around for o in string1:

@batFINGER Agreed; shouldn't that throw an exception without a pass body?

My assumption is either the for loop can be removed as o isn't used, or the if block needs to be indented.  Either way c will always be 2.

Can do this without operators.  I've set script to run on all objects in scene with a name starting with "Cone".
A common blender technique is to select an object and simply use
cone = context.active_object

Here is test code that adds a random z scale for cone on each frame from scene.frame_start to scene.end_frame.
import bpy
from random import randrange
from bpy import context
scene = context.scene
cones = [o for o in scene.objects if o.name.startswith("Cone")]

for cone in cones:
    c = scene.frame_start
    while c <= scene.frame_end:
        a = randrange(10,30)
        b = randrange(3,6)

        cone.scale.z = a / b
        cone.keyframe_insert("scale", index=2, frame=c)
        c += 1

Many thanks. Can you explain why to start from frame 2(Still learning,Baby Steps)

Used your c = 2 is the only reason for 2.   For all frames in scene frame range use c = scene.frame_start instead.

c = scene.frame_start , How I will use it?(Sorry for the ignorance)

Edited answer accordingly.


text:
Imported FBX animation looks strange on action editor
I made a rig and a set of animations in a Blend file and then lost the file.
I do have a FBX file that I exported with the mesh, rig and animations.
I've managed to import it into a new Blend file, but I have the following problems:

Instead of displaying the bone names, it displays the X Y Z Location, Quaternion and Scale for each bone.
It made a keyframe for every single frame in the animation.

Is there a way I can fix this to get the file back to an editable state?

The "keyframe for every single frame in the animation" part of your question "is a feature, not a bug": That is how Blender outputs an FBX.

In object mode, select your armature. I imagine you may not be able to see it unless you turn on Xray.

Now go into pose mode and Blender's Animation screen set up.... or, I find this easier, anyway:

Your dope sheet will show you which bones in the armature have actions keyframed to them. Although Blender creates a keyframe for each frame, it does not create one for each bone -- only those bones that have actions associated with them.
In the NLA editor, you can turn this set of keyframes into an action strip, and you can B box select and simplify.... but it is still less elegant than what you undoubtedly had in your original Blender file.
Regarding names and axis... does your file look like this?

If that's what you are seeing, you can turn them off under the Armature panel.... but I have seen weird issues with some FBXes (more often scaling and orientation than naming)... and frankly I typically just hack at them until I get what I want... That is not really an answer... just what I do.
best
rg


text:
Is it possible to generate a splatmap out of a hand sculpted terrain?
I've sculpted a terrain which for artistic reasons has to be hand made.
Now, I'm wondering if maybe there's some type of shader I could do to generate a splatmap from this terrain, so I can use these as a starting point for my texture masks.
Any pointers?

Are there any particular maps that you interested in? Splat maps can be used for many things. A Height-gradient or a Facing-up-gradient are trivial for example.

Well, what I'm trying to do is take a hand sculpted terrain, and create a series of texture masks so that I can use them to distribute materials on the level automatically based on a set of parameters.
Ideally I would take my sculpted terrain to something like World Machine, and generate a texture mask to distribute materials based on slope angle, and things like that, so I can get a more realistic result.


text:
3D audio visualizer in blender
I would like to create an audio visualizer in 3 dimensions in Blender, like this :

How can I do it?

Is this visualizing the wave form? or just how loud the track is?

It visualizes the amplitude and Frequencies by the time. link

oh, so you mean like an EQ? When there is bass, the left half gets bigger, and when there is treble the right half gets bigger?

What have you got so far? What have you tried, and what didn't work? A simple google search yielded a lot of results

@DuarteFarrajotaRamos This kind of animation are in 2 dimensions (I did it yet with few plugins) I would like to create a spectrogram in 3 dimensions (time, amplitude, frequency).

There are a lot of ways to do it, you could bake the amp or the eq to f-curves, the second picture you posted was from the wavetable window in serum, which is not a regular audio visualizer, it's a scanned wavetable viewer. Not really sure what you are asking here.

authors: Костянтин Кримов


text:
Linear curve to wave curve
I would like to create a shape/curve similar to the white line on the picture below. From linear curve to wave curve.
How can I create this one?

Press Z to work in wireframe view

Enable Add mesh: extra objects with File -> User preferences -> Add-on

Generate linear to wave, with Add -> Mesh -> math function -> XYZmath surface and make sure you leave 'U wrap' blank:

Add a mirror modifier and enable the highlighted button:

Press Tab tp enter Edit mode and move the waves from each other:

Add a circle curve:

Then select the wave and add a curve modifier

Scale the circle curve:

Scale everythong with -1 along the x-axis and rotate to obtain:


text:
How to use shadow catcher in animation render?
I struggle to use a simple shadow catcher option on a plane,
If I render a single frame everything works perfectly:

but if I render an animation, the shadow catcher option on my plane doesn't work:

I just tried it and it works fine for me. Can you upload your file and I can take a look

Well, I try different things. My first render was on a Hackintosh, looks like to had the issue with my GPU. The functionality works well on a normal computer.


text:
Smooth cylinder after do kife cut?

As the image shown I did a cut inside a cylinder, then I want to smooth cylinder but keep the cut sharp. When I did smooth the shape distort around the circular hole :(

Related - http://blender.stackexchange.com/questions/3260/how-to-cut-a-rounded-hole-in-a-sphere

If you haven't solved this yet this is pretty good quick tut.
https://www.youtube.com/watch?v=salpctjEdAA

I suppose you did a Boolean cut. That gets the job done fast, but you'll have a hard time cleaning up the mesh after the fact. You would be better off by first cutting a hole in the cylinder with the Knife Tool, taking care that the topology is correct (quads only). Then select, inset and push the polygons that form the perimeter of the hole inside the cylinder. After that, select the edges surrounding the newly formed hole and bevel them. After you apply the Subdivision Surface Modifier you should have a decent looking mesh.

While correct, cutting a hole with Knife Project will actually leave nearly the same topology requiring cleaning up as cutting with Boolean.

Agreed. Maybe a better option would be more planning with the overall shape and poly-count, i.e. Boolean cut with a low-poly cylinder primitive and eventually adding edges with the Knife tool where necessary.

If the geometry of your model is not super important and you just want it to look the part you can set the shading to smooth on the object under the first tab on the t tray of the 3D view.
Then if you go to the data tab under normals there is an autosmooth option that will tell blender not to smooth edges that exceed the angle you set.

Hope this helps.

Non of those methods work perfectly, still some distortion after do mesh :(


text:
Human model and other textures won't show up on render
I've been making animations of different accidents happening to the human model and recently I grouped them in folders. When I made another one which is already made in a new folder but still used the base file of a previous animation, the human model and other textures won't show up. The weird thing is, the shadows show up but the 3d model itself won't. I've tried almost every solution I saw in the threads here such as disabling the Render Layer, checking the toggle buttons and the Disable Restrict Layer thing- nothing works. Our deadline is on Wednesday and I'd appreciate if someone would answer ASAP. Thanks.

And the blender file: https://drive.google.com/open?id=0B_pEJgt9uYGSTmxVNzRYTkllZVE

See if any of the things mentioned in this answer solve your issue.

The problem is that all of the materials are transparent. Change this in the material settings by disabling the transparent option.

It worked!!!!! Thank you very much!!!!!!!!!!!


text:
Save Collections as separate blend file
is there a method to write each collection and its content of a given blend file into separate blend files, each new blend with the name of the collection?
The process should be:

Take a blend file x.blend with n collections
specify the target folder where to save the output
each collection n of x.blend is then saved into the given target folder as a separated blend file n.blend, named after the collection.

Thanks for help!

The following uses hard coded windows paths for the ip_path, op_path but as the intention was to specify your own path and file this should be no issue.

Open a new blender file (the script will be removing all content from collections in the current file while running).
Copy the code into a text editor.
Modify the ip_path, ip_fname, op_path for your specific targets.
Run the script.

import bpy
import os

# folder containing blend files
ip_path = "C:\\Blender Projects\\bridge\\"
ip_fname = "bridge_002.blend"

# target folder
op_path = "C:\\Blender Projects\\bridge\\temp\\"

blendfiles = [ip_fname,]

def clear_cur_colls():
    while len(bpy.data.collections) > 0:
        bpy.data.collections.remove(bpy.data.collections[0])
    override = bpy.context.copy()
    override["area.type"] = ['OUTLINER']
    override["display_mode"] = ['ORPHAN_DATA']
    bpy.ops.outliner.orphans_purge(override)

def get_coll_names(assets_path):
    names = []
    with bpy.data.libraries.load(assets_path) as (data_from, data_to):
        names = [name for name in data_from.collections]
    return names

for file in blendfiles:
    # prep to make a folder based on blend file name
    filepath = os.path.join(ip_path, file)

    # make a folder based on blend file name to store new files
    if not os.path.isdir(op_path):
        os.mkdir(op_path)
    # get each object from blend file
    colls = get_coll_names(filepath)
    for coll in colls:
        # clear the current file
        clear_cur_colls()
        # append the object
        bpy.ops.wm.append(filepath=file, directory=str(filepath)+"\\Collection\\", filename=coll)
        # save blend file
        bpy.ops.wm.save_as_mainfile(filepath=os.path.join(op_path, coll+".blend"))

clear_cur_colls()

Hi Ratt,thank you very much for your detailed answer. One more question though: Why is it that the content of the collections of the input file will be removed? The initial file should remain unchanged, or at least as an option to choose to either keep it as is, or the remove all contents. Nevertheless i thank you for your great support!

@pixelpoems.de Your original file with multiple collections of items you want to retrieve from remains unchanged. The script clears it's own (open file's) collections so that the 1st save won't have your default scene cube light etc in it; and after the script imports (appends) a collection from your ip_path, ip_fname it saves itself as the collection name, it needs to clear itself before importing the next collection in the list of collections from your original file. This avoids using auto execute scripting and system commands to attempt to create blank blend files.

Hi Ratt, now i got it. Thanks a lot for your help! The Question is now solved.

Updated version from accepted answer, works in Blender 4.2:
import bpy
import os

# folder containing blend files
ip_path = "/home/alex/models/"
ip_fname = "level.blend"

# target folder where to place blend files from collections
op_path = "/home/alex/models/parts"

blendfiles = [ip_fname]

def clear_scene():
    bpy.ops.object.select_all(action='SELECT')
    bpy.ops.object.delete()

    for collection in bpy.data.collections:
        bpy.data.collections.remove(collection)

    for material in bpy.data.materials:
        bpy.data.materials.remove(material)

    bpy.ops.outliner.orphans_purge(do_recursive=True)

def get_coll_names(assets_path):
    names = []
    with bpy.data.libraries.load(assets_path) as (data_from, data_to):
        names = [name for name in data_from.collections]
    return names

for file in blendfiles:
    filepath = os.path.join(ip_path, file)

    if not os.path.isdir(op_path):
        os.mkdir(op_path)

    colls = get_coll_names(filepath)

    for coll in colls:
        # Clear the current scene
        clear_scene()

        # Link the collection to the scene
        with bpy.data.libraries.load(filepath) as (data_from, data_to):
            data_to.collections = [coll]

        for imported_coll in data_to.collections:
            if imported_coll is not None:
                bpy.context.scene.collection.children.link(imported_coll)

        # Select all objects in the collection
        for obj in bpy.data.collections[coll].all_objects:
            obj.select_set(True)

        # Save blend file
        bpy.ops.wm.save_as_mainfile(filepath=os.path.join(op_path, coll + ".blend"))

clear_scene()

You can run it in blender or save to separate python file and run with blender -b -P exporter.py.

Hello and welcome. Thank you for sharing. I tested the original version and you only had to replace bpy.ops.outliner.orphans_purge(override) with bpy.ops.outliner.orphans_purge()to make it work for Blender 4.2. Perhaps you can add additional explanations?


text:
How to create a cicular hole pattern with geometry nodes (flange hole pattern)?
It is asked to create a procedural circular hole pattern that should look like so:

The setup should not be done with booleans to get a clean topology. The inner holes (B) can always be 6-sides, as shown here:

This setup can be achieved by using this setup, but the gaps (A) still remain

Is there a way to either Fix the gaps (A) with clean topology (e.g. Quadrilateral mesh node), or to use a better setup?
Thank you in advance!

I know you said you do not want to use Mesh Boolean to keep a clean topology... but if you choose the right settings I see no reason why you should not get a clean topology?

Or if you want an edge running through the center of the ring:

Or like your reference with 10 holes in the ring, everything non-destructive and adjustable:

Sure, these examples have n-gons... but if you go for holes with less vertices like in your lower screenshot, you can maybe find settings to have it with quads as well. Personally I would rather go for the n-gon approach with still very clean topology.

Here's a fun idea: use a cone and delete some faces. Subdivision Surface will make circles out of them for you. Or ellipses. Or more like egg shapes: . It is a little bit of a joke, but maybe you could use it if you wanted to shade with respect to radial and in-out directions and don't mind the awkward quads which touch holes with only one vert:

Imgur mirror (SE image hosting has problems)

Imgur mirror
You need to adjust the "Radius Top" of the cone to the number of holes to make the holes roughly circular. Also for a small number of holes, the minimum radius top is too big, because it controls the top vertices which get deleted, so you would need to use non-zero "Radius Top" and only delete the top face instead of vertices.

Imgur mirror
You can make the holes perfectly circular, but you need to calculate their respective centers, then distribute the angles evenly, move all verts to average distance to hole center and maybe blur positions (pinning boundaries) afterwards...

With good topology:

After subdivision:

General setup (create instances of a plane+hole and rotate around):

Get dimensions setup (pretty straightforward, wheren X_Hole is the radius from the center of the flange to the center of the holes)

The core part: create a plane with a hole:

The creation is extruding from a circle, so topology is perfect.
One frame transforms the circle extrusion into a square
Another frame makes X of the square be the radius, and Y of the square be the angle of rotation (we will convert these coordinates to polar)

Convertion to polar setup:

Oh Man, thank you so much for this greatanswer! This is more than i expected, the issue is perfectly solved. One final Question tough: If you change the Number of verts in the "Mesh Circle" Node in the "Make plane Hole" Group to any value that is not 8, the mesh no longer works. This is because the Plane needs 8 verts to form a correct rectangle, is that right? Anyway, thanks again an greetings from Germany!

@pixelpoems.de, yes. I made it exactly with 8 for topology, thinking that 4 connects to the corners of the square and 4 to the centers of the edges of the squares. If you change that number, you will need to find other solutions to transform the extruded circle into a square.


text:
Colomanagement Workflow - how to achieve requested target RGB Values?
i think this is a colomanagement workflow qestion at its best. Imagine the following scenario:
Say there is a nitpicking customer, and he requests the following you from you: Deliver an image showing a sofa with three pillows on it, and the pillow colors shall be
-Pillow 1 RGB = 0.8 0.01 0.01
-Pillow 2 RGB = 0.75 0.8 0.065
-Pillow 3 RGB = 0.05 0.8 0.22
Thank god he did not ask for a canvas print with target CMYK Values! (but this is a topic for the upcoming discussion)
So, how in terms of managing colors, can i achieve this? Typing the given numbers into the color wheel of the shader input may be the worst idea.
I think this example explains what i am thinking about. From what i've learned so far, the problem can be compared with music:
I take my guitar, plane the note "c", this note i will record using a digital microphone. Then i take the recording on my computer, burn it on CD, put the CD into my hiFi system and play it.
What note will i hear?
So, the question again is: How can i achieve target color values at the very end of my color pipeline?
I'm loking forward for a good discussion.
Thank you in advance.

CMYK and RGB are relative colour spaces, and as a result, individual values mean nothing. In RGB's case, it means the intensity of three lights, a white point colour, and a transfer function which are not specified by the values alone[1]. In CMYK's case, it means four (or more) arbitrary ink colours as well as paper stock and illuminant.
Taken in isolation with no additional metadata, RGB values and CMYK values mean nothing, and there is no method to convert them.
In order to specify a distinct colour, values would need to be offered using another colour encoding model such as xyY, along with some additional context, or, optionally, in RGB with a clearly defined colour space. Same would go for offset work, via an associated printing colour space encoded into an ICC format.
It should also be noted that when dealing with shaders, you should not match sRGB values, for example, but rather match how the physical object reflects light relative to the lights used in the renderer's reference space. This is likely the subject of another post however.

I take my guitar, plane the note "c", this note i will record using a digital microphone. Then i take the recording on my computer, burn it on CD, put the CD into my hiFi system and play it.

It is closer to the idea of a guitar tablature; you don't know the guitar tuning, so playing the particular fret position is essentially meaningless without knowing the guitar tuning.
In much the same way, RGB values purely are intensities. What isn't communicated via an intensity value is:

What the colour of each light is for each red, green, and blue intensity. Is the red a purple colour, the green a yellowy tone, the blue a cyany?
What arbitrary scale the intensity is mapped to. Is it a physical ratio, a non-linear scale of one of the infinite out there, or some perceptual scientific ratio?
What the achromatic value is intended to be. What colour are we using as the adapted achromatic colour for our notions of white?

Hence, according to the ISO, we must answer all three of these questions before we can use the term colour space.
Given an RGB colour space and the values, we can get an absolute device independent notion of what the colour in question is, and convert it to any other domain accurately.
[1] http://www.iso.org/iso/catalogue_detail.htm?csnumber=37161

I remember to have had a client project a year ago, where nailing a target sRGB value was a part of the task (logo animation towards the company's CI color). I ended up tweaking shaders and lights until a color eyedropper would report the sRGB values requested, because I knew that on the client side, the person in charge would do EXACTLY the same. Entirely stupid workflow, and by far not as complex as the cushion example, as I was able to simply eliminate the shading at the critical frames.

Similar discussions happen when you ask clients or - worse - co-workers what resolution they require. The answer will most likely be "make it 300 dpi"...........

@aliasguru The good news is that there are tremendously accurate processes in place, but sadly many imagers throw their hands up because of all of the bllsit out there. It can be done, and accurately. The issue tends to be foundational knowledge. Imagers can insulate themselves by knowing the concepts, and can prove their case / make clients comfortable.

In therms of music, really good comparaison by the way, what you ( @pixelpoems.de ) hasn't take into acount with your exemple of the C key is, that in contemporary music there is an asumption that you play in A440.
It isn't always the case in classical music for exemple or in oriental music.
So your C key doesn't means anything without the information of C in A440.
https://en.wikipedia.org/wiki/A440_(pitch_standard)
It's exaclty what Troy explained with colors, your RGB = 0.8 0.01 0.01 (in music C key) doesn't mean anything if you don't specify the context, a clearly defined colour space (in music A440)
We think RGB is standard across software but each one see RGB in their own way.
It's like if you ask two musicians to play a C key but one tuned in A440 and the other tuned in 432, they will both play a C but you wouldn't hear the same note.
A440: https://www.youtube.com/watch?v=rFOl-9SNxLY
A432: https://www.youtube.com/watch?v=BJ8KdqhHk0w
By the way thanks for your question, now I clearly see how music and light are linked, after all they are both just vibration.
Hope it can help musicians to hear light. ^^

Edit : This answer is just a garnish of Troy's one, but clearer than a comment.

Edit 2 : In fact I haven't responded to :

So, the question again is: How can i achieve target color values at the very end of my color pipeline?

Because the question is more complicated than what it looks.
However I've read a good starting point :
http://colour-science.org/posts/the-importance-of-terminology-and-srgb-uncertainty/

So, first you and your client must be tuned on the same A, whether it's 440 or 432 or anything else, otherwise there will always be a discord.
What is to be, let say sRGB EOTF 0.8 0.01 0.01?
The based color of the object (Albedo)? The final color of the object in the picture? If so the part in the dark? The ones in light? And about the light, is/are it/they achromatic or colored?
I think you see the point.

the analogy to music helps a lot. Maybe it should be used more as an example, because it fits in many cases. Say That Tone is Hue, Saturation is loudness and value is pitch, many color management problems can be transformed as music problems: 32 bit = wav = exr, 8bit = mp3 = jpg, bad monitor = bad loudspeakers. All the synchronisation issues have paralles. How can we use the analogy to explain color managment? i'm looking forward to the disussion!

It helps musician, don't know for the others.
But yes I think too it's a nice aproach.
It will definately helps me to explain things.
It's funny because I know that music can be a guide to understand whole life but never thought about using it to explain 3D.
It just comes up with your exemple.

So, the question again is: How can i achieve target color values at the very end of my color pipeline?

For me, the end of the color pipeline is always the compositor.
I'd render the pillows in white and mask out their positions in compositing (either with render layers or object id or material id, depending on your situation). Then use a color node to tweak the color. This is way faster than re-rendering the entire scene for every change.
Since, as already mentioned in other answers, simple RGB values are not enough to nail a color, ask for some more data so that you can nail it. Alternatively, since testing out different values is so easy, make a lot of tests and ask your customer which one he likes best (this will probably require a live demo, but there's Skype so why not).
If you are rendering the pillows in white, you need to make sure it doesn't show in indirect lightning. If it does, try out one of those:

the pillow is white for camera rays, if not is has a color that roughly matches the final rendering. It's just for indirect, so it doesn't need to be exact.
Use render layers
Bake the "correct" (colored) light the pillow "emits" (diffuses/reflects) to your sofa (and other props that are affected) to a texture. Adapt your sofa material. Change your pillow back to white.


text:
Diffusion confusion - what is the right diffuse shader yor which application?
with this i would like to start a question / discussion of what type of diffuse shader is to use for which specific application. Cycles comes with a "Diffuse" Node, but other nodes do diffusion as well. Here is an example:

The Question is: What type of shader should be uses for which specific case? What are the differences? Should they be mixed?
Thank you!

Diffuse is a regular basic diffuse shader for materials with no or negligible reflection or refraction. It is usually used in combination with other shaders, more commonly with Glossy. Velvet as the name implies is used for fabrics with a 'metalness' to them, like silk or velvet. Don't know about the other ones, never used them myself. I've always though of the as specific optimizations for certain situations.

Use diffuse for diffuse reflection, use glossy for glossy/specular reflection, and mix them because real materials also have multiple types of reflection at the same time.
It is a common misconception to think that diffuse reflection is caused by the surface irregularities/bumps, but this is wrong, perfectly smooth surfaces still can have diffuse reflection. Actually diffuse reflection is caused by subsurface scattering, but the scattering distance for most materials and rendering scenarios is smaller than the pixel size, therefore luckily we can use the diffuse node instead of the slow subsurface scattering node.
For more details, see my answer to a similar question: What is the technical difference between a diffuse shader and a rough glossy shader?

Hi Ibalazscs,thanks for the reply; i did not notice that my question was posted before; your answer there is very useful. Thanks !


text:
Overlay Text to an image in the Compositor
is there a way to overlay a text over an image in the compositor? I usually add my website URL to final images o post on the web, and everytime i need to open the final image in gimp to overlay text. See an example here:

[Overlayed text in the lower right corner]
I already tried the stamp output under the render settings, but there is no way to choose the font type and/or the position of the text. Both should be possible.
The only useable method i got by now is to create a text as image with alpha in Gimp and then overlay it. Is there a better method?
Thanks for help!!

Hi cetagon, this is not what i meant. I need a solution for a Compositor NODE, not a text object of 3D space.I don't want to render out something over and over again that is already there- It should be similar to this thread, that unfortunately remained unanswered as well:                                                                              https://blenderartists.org/forum/showthread.php?392789-Blender-Cycles-Improvement-Idea-Text-Texture-Node

Sorry for the misunderstanding cetagon. I thought it was clear that the phrase "overlay a text over an image" explained that i am searching for a way to use a text from a text editor, not the 3D Text object. Anyway, is there a chance to do so?The Render layer solution is the same as overlaying a text using gimp or photoshop.

This post is quite old but got no answer and I faced a similar issue so here is a workaround.
The idea is to use the image of a text and overlay it.

But if you just try to alpha over the image, you can't place it precisely in the corners. You first need to 'wrap' the watermark with a transparent frame of the size of the scene.

This way you can use the Translate node with the 'relative' option and then you can play with size, offset and transparency. Here is the node setup for the final effect :

The only drawback is that the X and y sizes of the watermark have to be entered manually. But if you need to do it just once, it's ok.

I can add one more drawback to adding text as image to your compositor and then rescaling it - You lose ton of quality of the original text when you're rescaling it. I'm looking for a different method without having to get my final render through PS.


text:
Init object every time file new is called
I'm using a Python class static members properties in order to store the state of the addon I'm developing. It works fine and my Python class is brand new every time I start Blender. Problem is, if I do file->new or revert, that class is not created anew and still stores values that are relevant to the old file. Is there any way to achieve that?

A persistent onload handler
Application handlers.
Code taken directly from Persistent Handler Example
import bpy
from bpy.app.handlers import persistent

@persistent
def load_handler(dummy):
    print("Load Handler:", bpy.data.filepath)

bpy.app.handlers.load_post.append(load_handler)

Other things to consider re comment for revert and new is look at
bpy.data.is_dirty

for toggle from True to False. Wont matter if  a clean file is reverted.

Thank you. So this will work in the load case. Not in file->new or revert cases. Nice to learn about handlers though.


text:
Submerged inflow doesn't add to fluid volume
So if you position your inflow inside the fluid, or where it's going to be submerged after a while, it stops producing fluid volume. Funnily enough, I've encountered the problem with both Blender fluid sim and Flip Fluids. Anyone knows what's going on an how to solve the issue?

Look at the constrain fluid velocity "Enabling this option will allow an inflow to push around fluid when submerged and can also be used to fill up a tank when submerged"

Hey, you're right, had not seen that one. One point for FF. Many thanks

Has this opting been removed? Should it be in the inflow object physics properties?
I can't find it in Blender 2.92.


text:
Parenting to bone make object move
I'm trying to make clothes for Manuel Bastioni generated meshes.
So I can parent a mesh to an armature and it keeps its transformation. However, as soon as choose a specific bone, the mesh undergoes undesired translations and rotations.
Here it is before parenting to a bone, but already parented to the armature:

Now parented to one of the armature's bones:

I can painstakingly replace the mesh afterwards but it's undergone too much transform to make it a matter of a couple of rotations.
N.B.: I cleared all position and rotation on the original mesh before parenting and it was in perfect position.
Any idea why it moves and how I can stop this from happening?

I suspect that the object your are trying to parent to a bone already has a parent. If that is true, then try removing the object's parent then parent it to the bone. This may not always be easy, depending on your object structures and dependencies. But at least it should solve the problem of the object jumping when you parent it to a bone.


text:
Nothing showing in Camera View despite scaling camera and checking clipping
I have a large model of a wheelchair and I put some materials on it. I set up a sun lap and a camera, after several attempts to see my work through the camera view, there was still nothing showing in the viewer (I can see it in the 3D viewer. I scaled the camera up so that it could see the whole model and checked the clipping, but still nothing. When it enters camera view, it does not zoom straight in and look through the lens, it makes a sort of orbit into the lens which is confusing the daylights out of me. Here is a link to the blend file:
https://drive.google.com/open?id=0BxZR-5RoJhhZNndqRG96ZzhpUVE
I am a Blender beginner, please pardon my rookie stupidity.
Thank you

Hi, I downloaded your file (next time if possible please use this service http://blend-exchange.giantcowfilms.com/, it will provide a link that you can paste in your question, using the edit option), and it has some scaling issue, apart that pointed out by Tak below. I will try to guide you to reset those issues later, but can you also edit your question and describe how you got that (complex) object into blender?It seems some kind of import, from another program, and this often leads to scaling/viewport/units  incompatibilities. It would help all to understanda what happened here.

Here is what I see in your file that is strange (as said above, it may be due to some imported file and/or some later transform by you or others), and I'm quite sure it's causing all kind of weirdnesses you experience in your file:

the camera is gigantic, both in scale and size, and its location seems strange, values are too high for typical blender files.
Also you see the camera clip values are ok (default values), but the interactive view has way too big values: 1.5 and 10015 !

the grid, too is gigantic: 300 while the standard is 1 ?

and also the wheelchair (eg: the selected wheel) seems gigantic, although the scale is 1...
As you see, there is something wrong: I could correct your scene, like this: first of all, I reset "wrong" values of your grid, view, wheelchar, camera, lamp guessing they could be some hundred times higher than "normal". Where "normal" is a coherent range scale of all scene elements that makes the blender files view and manipulation (including camera view) beheve predictably, and "well".
So:

the wheelchair: I selected the controlling empty of all the chair elements, then I changed its location to 0,0,4 (almost grid center) and scaled it down all by 0.01 (that means 100x smaller): this makes also all the parented wheelchair elements to be transformed as the emtpy.
the camera: I changed its location to +30,-8,+45 and set its size back to 1, and scale to 1,1,1.
the lamp: I changed its location to -5,+12,+45
the grid: I set its size back from 300 to 1

lastly,

the view: I set view clip to the standard 0.1 - 1000.0 range

Now, everything seems to have disappeared! It's not, of course, its just that everything is reset to "standard" dimensions, and your view is still as previously: pressing the keyboard's "home" button (ie: "show all") should make your scene be visible again, well in the center and with proper view, grid and camera settings. And now I have this:

Let me know if you need to download your file corrected, but it would better that you try to repeat my steps above, so you can practice for similar situations in future.
Please don't forget to add details about how you got that file (import, transforms), if possible, because it will let a trace for other users in similar situations...
Here is the corrected file (now with a single 3d view area):

Thanks for all of that info. I will do my best to reproduce your steps but I still may need your corrected file for reference. I'll get back to you ASAP. Thanks!

@Tak Something is not right, I'm going to need the corrected file if you don't mind, things are all wonky. Maybe it's something with Blender. I am going to reset to factory settings and see if that helps. Thanks!

@Christina Parissi ... I'm not Tak, he added another answer..  I'm m.ardito. I added the (corrected) file at the end of this answer...

thank you for the blend file. I saw that you split the view into many frames. I moved the timeline down but now the windows aren't joining by the normal method clicking and dragging the upper corner. Sorry to be so much trouble.  Di you have any ideas?

@Christina Parissi don't worry, although in that version of the file the windows were perfectly collapsible as usual, now I uploaded a new version of the same file, which has a single 3dview  as in the default blender workspace... please download it again.

The problem is that the clipping End limit is too small. I've changed it to 6000 and it's working fine. To be able to view the clipping range you can tick the limits checkbox in the Display panel and a beam will be shown in the camera showing its clipping range as shown below:

Camera view:

Thank you, I had no idea the clipping would have to be such a large number! Would it have to be a large number like that if I moved the camera closer to the model?

@ChristinaParissi If you moved the camera closer to the model then you can decrease the clipping limit. Please accept the answer and tick as solved if it solved your problem to help future users having the same problem.

I don't think that is the (only) real problem... this file has also some other weird setting...


text:
How to overlay Alpha masked image over finished Video without re-rendering the whole track?
How can an alpha masked image (PNG with alpha) be overlayed over an already finished video footage?
I have a filmed (not rendered) Video footage with approx 40.000 Frames. Over the first 200 frames, there should be the mentioned overlay.
Everytime i do so, the whole video strip renders the wholel 40.000 Frames, even tough only the frist 200 were changed by adding the overlay.
Is there a way to change only the first 200 frames by adding the overlay, and then "stitch" it to the unchanged remaining 39.800 frames?
Thanks for help!

The only way I know is to split the video in two parts (200 frames and the rest), do the changes to the first part, render it, and than join the parts.
BUT! To join parts without decoding the second one, you must render the first one with exactly the same parameters (codecs and so on). There are different programs for splitting and joining footage without decoding. It's not a problem to find one. But the main problem will be to adjust rendering parameters for the part that will be changed. Otherwise it will be decoded and than it all doesn't make any sense.

for splitting and joining I can recommend you My MP4Box app


text:
How to batch rename embedded (linked) textures in a scene?
is there a way to batch rename all textures that are used by the all objects in a given scene? Background of this question is as follows:
I'm creating a set of models that all will be textured (diff, roughness, normal), and all textures will be of 4k size.
After creation, i want to have a copy of the 4K textures in 2k size. Therefore, i export all textures by using "File" --> "External data" --> "Unpack all into files". Then, i use irfan view to batch resize and rename all textures, giving them the suffix "_2k". But when i re-link the files, the file connection in the shader nodes is lost. They need to be re-linked manually. Doing this manually is ok for a small amount of textures, but this time i will have about 100 textures.
So, how can i achieve to rename all textures without loosing the connection to the shader nodes? Some advice will be very helpful.
Thank you in advance!

This question was answered at blenderartists. See the solution with a phyton script here:
https://blenderartists.org/forum/showthread.php?441069-How-to-batch-rename-embedded-(linked)-textures-in-a-scene
Thanks to the users Photox and MartinZ for help!


text:
Remove edge loop from selection in 2.8
What is the best way to remove a whole edge loop from an edge selection in Blender 2.8?

The Process is as follows:
a) in edit mode, select three (or more) Edge Loops with double click shift + LMB
b) with three edge loops selected, remove loop "A" from selection without losing the selection of "B".
How can this be achieved?
Thank you in advance!

You cannot select loops by double-clicking Shift+LMB in default Blender's 2.80 keymap. The hotkey for selecting edge loops in 2.80 is Alt+LMB by default. If you wish to add to the selection or subtract from it something that is already selected you hold Shift while using Alt+LMB.
So the answer to your question is:
When you select a few loops with Shift+Alt+LMB click, you can deselect them the same way clicking LMB while holding Shift+Alt on a loop that is already selected.

Hi Martin, thank for your answer, but this one does not work if you activate "Emulate 3 Button Mouse in the Preferences. If 3D Button Mouse is disabled, you are right. If it is active, you can choose edge loops with double click, but not de-select certain edge Loops. I'm using Blender Version 2019-04-17 19:26, Hash: b46245470f79.

That's a bug. You should report it through Help -> Report a Bug. It is understandable they forgot to check this. If you asked me, I would say just do yourself a favor and buy a 3 button mouse. You can get one that works fine for less than 4 euros.

Thanks for the reply Martin. If its a bug, your answer solves the issuse.

Use edge select. Delete the faces or merge faces


text:
Round of a half cut cylinder with subsurf
im trying to model a half cut cylinder with an axial cut section. The Cylinder has a subsurf modifier. As long as the cylinder is cylindrical, it is perfectly round (Type A). If i remove the half of the cylinder using a boolean operation, it stays round (B). But if i remove the verts in edit mode, the shape is no longer round (C ):

Is there a way to model a shape like C without a boolean modifier? The problem is that the cylinder i part of a larger model, and if i cut it, the topology gets destroyed:

Using the Boolean Modifier alone is not a solution as the model should be low poly and be exported into another application.
Thank you for help!

Have you tried adding control loops close to the edge where the distortion happens?

Likely faces on the cut ending change the edge flow and cylinder doesn't appear to be round. After Boolean (or manual cut, sometimes is best) delete faces on the mirror plane like on the first screenshot.

Add a cylinder;
Apply E and S to the bases and delete created faces. Remove doubles;
Join the edges with Bridge Edge Loops to make inner faces. The result should look as below;

In face selection mode select, with B, and delete half of the cylinder created thus;
Make faces where the crossection was made (see the image below);

Done.
If you want you may make more quads with Ctrl+R

Hi Lukasz, You are right with your answer. I did the same method before, but i had to less verts on the circle circumference. Try your method with only 6 or 8 verts on the circumference, and it will fail at subdiv level 3. Anyway, your method is usefull. Thanks a lot!


text:
How to animate plane to sound falloff in animation nodes 2.1 (Blender 2.8)?
For Blender 2.8, i tried to recreate the sound falloff on a plane from the Animation nodes 2.0 Documentation:

So far i came up with this, but it does not work, i can not figure out why:

Can someone give a brief explanation of how to work with the new Sound Spectrum node in the latest animation node version? The Grid mesh node has also changed. Is this causing the error?
Thank you for your help!

Connect "Frame" to Time Info node in Sound Falloff node so that it has frame information

Please include more detail to improve this answer.

hey man first thanks for the post this is what I ended up with. Its working its been tested.


text:
How to fix and reshape messed up shapes in sculpt mode
i’m trying to get more into sculpting. While doing so, i’m sculpting a fetus model. During that, i lost my attention to the hands. Now that i am in Dyntopo mode already, i need to fix the hands:

Using the Grab Brush alone makes things even worse. It is also very difficult to mask out all the rest of the sculpture. And mesh editing in Edit mode is almost impossible due to the Dyntopo mesh.
What would be the best strategy to fix the hands?
Any help is appreciated.
Thank you in advance.

What exactly are you trying to fix with the hands? From what I understand after reading your question, I assume you want to fix the right hand of the fetus since there are only four fingers, right?
If the fingers were the problem then I would go ahead and delete them. I would then create new geometry to fill up the holes where there used to be the fingers ( using the boolean operator Union to join the new geometry to the fetus's hand). After that, I would use the "snake hook" brush to pull out new fingers (enable Dyntopo when doing this step so that the brush can pull out enough geometries to form new fingers).

To fix the hand, there is an addon that will make this very easy for you :) THe addon exists for Blender 2.79 and 2.8.
https://blenderartists.org/t/mask-tools/642502/38
https://github.com/bookyakuno/-Blender-/blob/master/maskTools_2-8.zip
This will allow you to create a vertex group of the body and hand, and mask them off separately in the sculpt room.
I hope this helps. Cheers!


text:
How to build a six Colorchannel Grayscale Controler in the Compositor (Similar to Photoshop and alike)?
I try to recreate a Color to Black and White converter for the compositor that can handle six color channels, similar to those ones in Photoshop or Affinity. By now, i recreated the standard "RGB to BW" Node like shown below (marked as "a"):

But how can i add three more controls for yellow, cyan and magenta? In the image marked as "B" i tried to add another node tree, but the setup does not work. In the end, all values add up to 1, so that the resulting image ist pure white. What needs to be done on "B" and "C" to get a controler like this one?

Thank you in advance.

The source of the color wheel is: https://cdn-anmjh.nitrocdn.com/aZshDqLVEmlWiMiqnTaNayPsrwIdUduT/assets/static/optimized/rev-073579c/articles/img/rgb-primary-color-wheel.png


text:
Translation Matrix Coordinates
I have been reading many of the threads here regarding translation matrices and converting.  I am still confused as to how this works to apply to my project.

I currently have a camera object that is a child of my nurbs_path. I have a constraint on the camera for follow path.  Everything is perfect.  My camera is at correct starting location.

What i have figured out so far is that

print(camera_object.location)

gives me the translated coordinates based on the parent.  I don't completely understand this but not a huge issue at the moment.

My output from print

Vector (-0.0017, -6.6515, 5.0000)
Vector (-0.0017, -6.6515, 5.0000)
Vector (58.6404, -36.0573, 3.0000)
Vector (15.9993, -53.7008, 3.0000)
Vector (58.6404, -71.3442, 7.0000)
Vector (15.9993, -88.9877, 10.0000)
Vector (58.6404, -106.6311, 5.0000)
Vector (15.9993, -124.2746, 6.0000)
Vector (58.6404, -141.9181, 7.0000)
Vector (26.6596, -159.5615, 8.0000)

What i am trying to do is keyframe this camera path to certain timings.  A guy on blender artists showed me how to do the keyframing and i can do it in UI.  I have the keyframes set up but get wierd camera behavior after applying the keyframes.  I am guessing this is because of translation based on my research.

num_points: Length of a list

camera_object and scene are defined before this loop

verts: list of postions (time_offset, X, Y, Z)
     : X, Y, Z are in global space (i think??)

for point in range(num_points):
    current_frame = //calc to get frame number from a time offset
    print(camera_object.location) # print current camera location
    scene.frame_current = current_frame_num
    camera_object.location = verts[point]
    camera_object.keyframe_insert(data_path="location", frame=current_frame)
    previous_frame = self.__user_points[point]

The keyframes are inserted at frame 1, 241, 481, +240 frames each time to frame 2160.

Here is a pic before keyframe:

Here is a pic after keyframe:

The camera is the selected object to see it easier.

These are the coordinate of the verts list:

[[-0.0017454936660825002, -6.651534000393163, 5.0],
[58.64040695838593, -36.057303922236066, 3.0],
[15.99932173602529, -53.70076587534348, 3.0],
[58.64040695838593, -71.3442278284509, 7.0],
[15.99932173602529, -88.98768978155623, 10.0],
[58.64040695838593, -106.63115173466363, 5.0],
[15.99932173602529, -124.27461368777105, 6.0],
[58.64040695838593, -141.91807564087637, 7.0],
[26.659593041615448, -159.5615375939838, 8.0],
[79.96094956956625, -165.44269157835362, 9.0]]

Any help would be appreciated.

I've found it prudent not to parent cameras direct to a path, rather have an empty parented to it instead and parent the cam to that. Constraint conflicts have disappeared after that.  Timing, stops and starts, and speed variations are possible within paths.  I have done this some time ago.

is that what this is.  A constraint conflict?

Not sure by your question but my suggestion has cleared a lot of 'jittery' cameras.  It frees the cam to pursue it's own constraints.

I am new at blender and animation so bear with me.  I just learned about constraints yesterday.  I have never used an empty so i will have to look into that.  As for my question if you look at the picture.  At frame 241 before keyframes the camera is on the path but not at the point where i want it.  I want it ahead on the path where it turns.  After i insert keyframes in the second picture you can see that at the same frame count the camera has flown way off the path.  So if creating an empty will resolve this i will look into it.

ha ha I know how you feel !  When first exploring Blender over some months I invented an entirely new language - most of it unprintable !  I'll keep an eye on this space.  There are heaps of very clever Blenderites in here so you're bound to find a solution to most problems.

Appreciate it....and much of that language is vulgarities....lol

I expect part of the issue comes from you having the camera still following the curve after you have keyframed it. Remove the follow path constraint from the camera after you have the locations for the keyframes.
For your code - don't change frame_current, you should use frame_set(), but in your example you don't need to use either as you are specifying the frame when you create the keyframe.
I would use something like -
import bpy

# each item is time_offset, x, y, z
verts = [
    [0.0, -0.0017,   -6.6515,  5.0],
    [0.1, 58.6404,  -36.0573,  3.0],
    [0.2, 15.9993,  -53.7007,  3.0],
    [0.3, 58.6404,  -71.3442,  7.0],
    [0.4, 15.9993,  -88.9876, 10.0],
    [0.5, 58.6404, -106.6311,  5.0],
    [0.6, 15.9993, -124.2746,  6.0],
    [0.7, 58.6404, -141.9180,  7.0],
    [0.8, 26.6595, -159.5615,  8.0],
    [0.9, 79.9609, -165.4426,  9.0],
]

camera_object = bpy.data.objects['Camera']

for point in range(len(verts)):
    cur_frame = 2160 * verts[point][0]
    camera_object.location = (verts[point][1],verts[point][2],verts[point][3])
    camera_object.keyframe_insert(data_path="location", frame=cur_frame)

You rock!!!!!  it was the follow path constraint.  Removed that and the frame_set and works almost perfectly.  The camera swings wide to create a smooth curve instead of following the path explicitly.  If i change to linear interpolation that should resolve that, correct??

Everything is perfect.  Changing interpolation to linear fix that last issue.


text:
Anchor hud pane on camera bounds
Is there a way to figure out the frustum bounds of an orthographic camera using Blender Game Engine?
I'm trying to anchor some panels on the corners of the screen without success .
I'm working with two scenes , one with a camera perspective and another with the orthographic camera ( hud )
Thanks in advance

This is a good question. If you can add a screenshot of what you're trying to accomplish, it'd be even betterer.

...and welcome to B.SE, btw!

Here is where you set it:

It says 7.314, therefore the camera is 7.314 wide.
As to doing it in real-time, the python API you are looking for is camera.orthoscale to get the width of the camera.
Sample code (untested):
aspect_ratio = bge.render.getScreenHeight() / bge.render.getScreenWidth()
height = aspect_ratio * camera.orthoscale
top_right = camera.getAxisVect([width/2, height/2, 0.5])
bottom_left = camera.getAxisVect([-width/2, -height/2, 0.5])

Note that the 0.5's in the getAxisVect are to place the object slightly forwards of the camera to ensure it get's viewed.


text:
Completely hide armature influence temporarily
I've modeled and rigged a character, however I want to model different sets of clothing for that character.
Because I'm using IK on the bones, even if I reset all the bone's positions via a -> a -> w -> Clear User Transforms (All), the character's arms and legs are slightly offset from the model's default position in edit mode.
How do I completely remove the visual influence of the armature from the character without having to parent it again (because I have custom weight paint fixes I don't want to lose)?

Nevermind, I found the answer to my question. The armature transforms are treated as a "modifier" on the character mesh. All I had to do was deselect the eye icon for that modifier.


text:
Recreating Edge Split Algorithm
Does anyone have any insight to how Blender's edge-split algorithm works?
I need hard lighting for an OpenGL project I'm working on that uses per-vertex normals to calculate shading, and I'd rather not have to go through the trouble of rewriting the engine to allow for both per-vertex and per-face normals to calculate lighting. I think it'd be easier to just apply the edge-split algorithm to imported models that use flat shading.
Thanks.

That's more or less exactly what I was looking for -- thanks.


text:
Textures won't work on some objects
I am working on a scene, and am on UV mapping and texturing phase. I have managed to successfully UV map and texture a few objects, but for some weird reason now the objects I am trying to UV map won't take textures. In 3dview and render they are appearing pink, which I know means Blender isn't finding the textures, but I am browsing to select the texture images. The images are there. In one computer, after browsing to select the image, the node fails to show the name of the texture. On another computer, the name shows up but the texture doesn't get applied (same .blender file). Any ideas? I am using cycles render.

Try to see if your textures appear in the UV/Image editor. If not,they are not in Blender memory, so try to reload them (Alt+R) or reopen the files

are you using this file across different computers? if so, the file paths to the textures will be different and not work.

For future reference it is advised to always create a main parent folder for your project and place textures and all needed assets in a sub folder along with your .blend file. Blender by default tries to use relative paths, so when moving computers or changing the file path the images will still work the the sub-folder structure is maintained.

I have seen something similar when I have forgotten to UVMap an object to which I intend to apply an image texture.

Please be more factual in your answer. An object will not appear in pink if there is no uv map but only to indicate a missing texture.

I was trying to be helpful - but admittedly with some uncertainty. I'll check the exact behaviour next time my work takes me that way.
New here.


text:
blender - scaling object with hair
I have a character with hair. Hair with simple children. When I tried scale down the object hair don't changes with an object. But if I change children to none, everything is fixed. If I put interpolated than all hair are mess up.
I tried different variants. I tried parenting everything to null object and scale it down (I read it on one of the forum). Also I tried to disconnect hair, scale the object and connect it again (not worked also). So how to scale the object down with simple children hair?

Please add screenshots and upload your blend file to help you

I solved the problem. I made a trick, I converted hair into mesh, mesh into the curve, added some resolution and thickness, and converted back to mesh...


text:
Need Help Removing a Green Screen, Movie Clip Node missing
I have a small clip with a green screen background that I want to make transparent (or just my other video behind it). I have looked at lots of tutorials that feature the node editor to do this. However, when I try to make an input node, "movie clip" is not an option like in some of the other tutorials. I have blender 2.75, is it moved? Is it missing? I am very confused and don't know of any other way to make this work. Thanks for the help!


text:
Why does Blender use the previous keyframe properties when trying to insert a new keyframe?
I'm trying to write a script that does some animation task for me. The keyframes in this in this animation are created using the build-in "animall" add on. Animall animates some transformations on the surface of an object. The animation consist of repeatedly going through this process:
default state -> generate some transformations with animall -> back to the default state
(repeat for the next set of frames)
The code I use to accomplish the animation boils down to this:
for frame in range(0, max_amount_of_frames, frames_per_event):
    # "+ 1" to keep all the events split, not sure if it's needed though
    animate_event(frame + 1, frame+frames_per_event)

def animate_event(start_frame, end_frame):

    # Create the default states
    bpy.data.scenes["myScene"].frame_current = start_frame
    bpy.ops.anim.insert_keyframe_animall()

    bpy.data.scenes["myScene"].frame_current = end_frame
    bpy.ops.anim.insert_keyframe_animall()

    # Do the event
    mid_frame = int(start_frame + (end_frame - start_frame)/2)
    bpy.data.scenes["myScene"].frame_current = mid_frame

    doEvent()
    bpy.ops.anim.insert_keyframe_animall()

This works for the first iteration, but on the other ones Blender copies the properties of the last added keyframe (in this case the generation event) to the newly inserted keyframe. (so the first added keyframe of the second iteration becomes the last added keyframe of first iteration, instead of the default state)  The weird part is that Blender only does this if I run my script, but not when I perform the process manually.
Why does Blender behave like this? How can I fix it? Suggestions for another methodology for my animation task are also welcome.

Try using frame_set(x) instead of frame_current=x see this answer

Thank you, this totally fixed it. I find it pretty weird though that my previous incorrect method with the getter seems to have the same behavior (with all the keyframes being inserted on the right frames), but created a very different animation. Can you maybe post this in an answer so I can mark the question as answered?

Possible duplicate of Render specific frames with opengl via python

Could you explain to me why this is a duplicate question? I see how we make the same mistake, but our goals and problem descriptions are very different. (I might be wrong in this though)

The cause of both issues is trying to change the current frame using frame_current = x when you need to use frame_set(x). This boils down to the current frame not being changed which messes up further steps, whether you are rendering an animation or creating keyframes, both break when the current frame is not set correctly.

Actually, it does change the current frame. Try it yourself maybe.

I might be wrong in this, but while both questions were solved by the same answer (the problem lies in the same cause), the questions themselves are very different so I'm not sure wether it is appropriate to mark them as duplicates. (e.g. "What is the most sold four wheeled transportation vehicle" and "What is your prefered  method of transportation for getting from your home to your work?" both can have the same answer "car", but are very different questions)


text:
Change object pivot point orientation
For some reason the pivot point on my object has become rotated (other objects show normally oriented pivot points). I have to set the "transformation orientation" (see the bottom of my screenshot) to be able to see it though. Does anyone know how to change it back? That is, change it to be aligned with the "world orientation".

Have you tried hittin CTRL-A and apply location? And if it still doesn't work hit CRL-A and apply rotation.

This is intended behavior, if you are using Local Coordinates the transform gizmo orients itself to match the object local coordinates.
If the object is rotated so is the pivot, to match the objects orientation.
Either clear the object's rotation if it is not wanted (Alt+R), apply it so it becomes part of the object geometry (Ctrl+A), or use Global Orientation instead.

I'm still not sure what caused it, but ctrl+a -> apply rotation did the trick.

@rien333 This is because you transformed your mesh while in Object mode.

I turned off the snap tool, and this fixed my problem.


text:
Export unfinished image render
My render is "almost" complete...

It took almost 5 hours to render the center object, and from now on Blender will render nothing but white pixels of the Emission background all the way to the edges.
According to its estimations, Blender is going to spend 2 more hours rendering all the white background:

I don't need Blender to do this; I could easily bring the current data into an app like Photoshop and flatten to get the background to be white.
But I cannot save the image in its current state:

I cannot take screenshots and combine them either - it would take too long at 100% (Image is over 8000 pixels wide).
I'd like to restart my computer, or start another Blender project, etc... and would like not to have to wait 2 hours.
Can I save the current, unfinished state of my render as an image if the elements I need have already been rendered?

This looks like an instance where a Render Border would be useful, then compositing in the rest of the white.

thank you! it helps me a lot! save my prodject and my nerve cells!!!!!

Please don't add "thanks" as answers. Invest some time in the site and you will gain sufficient privileges to upvote answers you like, which is the Blender way of saying thank you.

Yes, you can.  You will simply click the X beside the Render % or press Esc to cancel the render.  Then press F3 as usual and it will save the rendered portion to your desired format/location.  The unrendered part will be black if saved as a JPEG and transparent if saved as an Alpha PNG.
Just to prove it ;) here you go:

Here's the canceled render of the default scene saved as a JPEG:

EDIT: As was mentioned, Render Border can be useful in certain circumstances.  The problem is it's always rectangular (so it wouldn't have helped in this situation with a circular object) and it's usefulness is relegated to instances where you use multiple render layers.  Otherwise, you can simply crop the render dimensions as close to the edges of your scene as possible which does the same thing.

Great! Thanks! What is Render Border?

@MicroMachine - You're most welcome.  Render Border (Ctrl-B) draws a rectangle within the camera frame.  Anything inside the border gets rendered, anything outside is not.  The problem is you can't draw freehand shapes so it's usefulness is stunted.

Didn't work for me, they must have changed things since 2.9.

@Dakacha Yeah this was back in 2.78.  A lot has changed since then.  Weird that they wouldn't have made this possible though.


text:
Compositor doesn't affect Alpha plane

In this render, the butterfly is an Image imported as plane with Alpha.
The non-transparent parts of the image have an Emission material with 18 Strength.
The Sphere above the butterfly has Emission material with 18 Strength.
However, once composited, the Glare effect from the Compositor seems to only work on the Sphere and not on the Alpha PNG.
How can I change my Node setup so that the Image-Plane also be taken into consideration by the Compositor?

I think the short answer is that the image plane is indeed being taken into consideration.  I checked that by altering the colors of your image so that the butterfly is white instead of pink.  In this case, the glare node does affect the butterfly.
I think your best bet is to really crank up the strength of the emission shader for your butterfly (I tried 200), which will give you the glare. If you want more control over the color of the butterfly image itself, you could experiment with render layers--use one layer for the butterfly image to be "glared", another layer for the color to be composited over top.

So in the image you are posting, you just cranked to 200 the plane emission? I was under the impression that the Mix Shader was not making the Emission value smaller by dividing it, but maybe I was wrong?

When I opened your file, you had your butterfly plane material's "Emission" component at 18.2.  I changed that value to 200.  The mix shader (as you have it set up) is simply making part of your plane transparent, it is not touching your emission values in any way.  My point is that the glare node seems to create glare around colors that tend towards white, the pink color you chose for your butterfly is not white enough to get a noticeable glare effect.

Option 1: Change the Threshold
The glare node checks pixel values. And only take into consideration pixel values that are higher than the Treshold value of the glare node.
Bumping the Threshold to a low value the pixels of the image are also taken into consideration. Between the values 0.1 and 0.4 the image of the butterfly are also taken into consideration.

Option 2: Extract background for even more control
In order to really not influence the background it is better to first mask it Extract it, calculate the glow and add the glow to the original image.


text:
Motion Blur and imported images
I am trying to simulate accurately the merging of colors when a color wheel rotates quickly.

This color wheel rotates 1980º on the Z between frame 1 and frame 40.
However when I export the animation, the colors are not blending:

We can see that the motion of the plane is, however, blurred (blurry areas outside the color wheel).
I have tweaked different settings in the Motion Blur tab of the Render panel, without success.
I would love a solution that is as physically accurate as possible.

Motion blur blurs geometry movement. Maybe propellor like blades of solid colour that were spinning. But then wouldn't it just give the gradient you have?

@sambler a colored disc that spins will see its colors blend (I had assumed it was a motion blur generating this effect), you can make the experiment at home with a spinning top or check out this video: https://www.youtube.com/watch?v=Ala7813u3Zg

That is a disc of solid colours, not a texture of colour gradient spinning. Make mesh blades with a single colour on each and spin them.

I've re-created a similar situation and this appears to be working fine.
Here's the image I have used to rotate :

It is essentially just a screen grab from the Gimp colour picker. I chose this in preference to your example due to it having more features (such as the triangular pointer in the middle) to make the effect more noticeable.
Keyframing rotation for 3600 degrees over 100 frames (a similar rate to your example) and setting Motion Blur shutter length to 2.00 frames produces the following result :

Turning the speed up even higher (36000 over 100 frames) results in almost complete merging of the colors as you would expect in the 'real' world :

Looking at your example file, I think your blur just isn't extreme enough to be noticeable. I increased the motion blur frames to 2.0 (from 0.5 in your example) and increased the rotation speed by a factor of 10 and got the following result :

Thanks for your solution, increasing the speed definitely worked out. In the exported animation frames, some frames show the disc less blurry than others, do you know what might be causing that? like here I feel the blur should be consistent, maybe I'm wrong

You’re welcome - glad to help. In the real world the blur would be consistent but Blender has to approximate the blurring. I beieve Blender produces the blur by sampling a number of sub-frames before and after the frame being rendered and combining the results. I believe the effect you’re seeing is where the speed of rotation is causing an interference effect as it is close to a number of full rotations in the gap between subframes. The problem should be lessened by increasing the number of samples used for the blurring - although, unfortunately, I don’t think Blender provides such an option.

I thought it had to do with shutter speed, as when a camera films wheels of a slowing car and the wheel seems to be spinning the other way for a second... Or if you look at a spinning object and blink, it'll look still


text:
How to set screen transform_orientation
I have not been able to find how to set this property in any forum.
I am trying to set the transform orientation from 'GLOBAL' to 'GIMBAL' through python.
blender api has the transform_orientation property:
https://docs.blender.org/api/blender_python_api_2_78c_release/bpy.types.SpaceView3D.html
I have not been able to set this property.
When i hover over the property in blender i get this
bpy.data.screens["Default"]...transform_orientation

**I know of gimbal lock.  Lets just assume i already know this and have accounted for it already in my rotations.
I have already manually set up all of this using the UI and it is working perfectly.  I just need to know how to set this property using python script.
Thank you.

are you trying this from within an Add-on or from a simple script / the python console?

Simple script python console basically.

[p for s in bpy.data.screens for a in s.areas if a.type == 'VIEW_3D' for p in a.spaces][0].transform_orientation

If you're using the script editor, you can do it like this:
import bpy

v3d = [x for x in bpy.context.screen.areas if x.type == 'VIEW_3D']

if v3d:
    # you need to decide what to do if there are more than one 3D Views present
    # you could either set the orientation on the first one, or on a specific one

    # to set it on all views:
    for v in v3d:
        v.spaces[0].transform_orientation = 'GIMBAL'

    # to set it only on the first one found
    v3d[0].spaces[0].transform_orientation = 'GIMBAL'

From an add-on, it should be:
# from within an Add-on, it's a lot easier, as you have a proper context
def execute(self, context):
    v = context.space_data
    v.transform_orientation = 'GIMBAL'

for proper context.  Could that be v = bpy.context.space_data?

Answered my own question there.  bpy.context.space_data does NOT work.  Your solution with v3d worked perfectly.  Thank you very much.

@ChrisOmlor, bpy.context.space_data works if in an operator and run from a 3D view. If not test space_data.type == 'VIEW_3D' before.

@lemon Makes sense.  That is where my mistake has been the entire time.  I was not in an operator and trying to grab the context like i do for the scene objects with bpy.context.scene.objects which does not work here.  Thank you for the clarification.

@ChrisOmlor note that with the operator method I'm not using bpy.context, but context instead. This variable is passed on automatically to the execute() method, that's why you have it in hand, and you can be sure you're dealing with a 3D View context.

@aliasguru Understood.  Which is why working within an add-on is easier because you have that proper context that can be passed into the method.


text:
Texture paint problem

Why i cant painting using texture ? it showing only color. I think about stencil brush mapping.

In order to effect the mesh you need to make sure the texture is loaded in the material. To paint onto it in cycles you need to make sure the image node exists in the node material and to have it effect the render it needed to be wired up.


text:
Creating a bag that will have different textures on each side
I'm attempting to model this bag in Blender:

I'm planning to export this as an .obj file and use it in 3JS. In 3JS I need to be-able to place a different material with/without a texture on every side - both outside and inside.
I have a model that I was using which allowed me to do this but I've ran into some problems with it and I think it would be overly complicated, for me, to try to fix it.
It allowed me to do the above by treating each side as an individual mesh that I can refer to in the 3JS world via an array index and place whatever I want on it.
How could I do the same with a mesh built from the ground up? And how do I draw the sides in?
Here's what I have so far:

And the actual Blender object:

Possible duplicate?: (https://blender.stackexchange.com/questions/516/add-different-materials-to-different-parts-of-a-mesh)

I disagree @NickBosse as I'm trying to do the different materials in 3JS - unless this is the exact same process then it isn't a duplicate

I think this is more question about three.js than Blender itself.

@LukeD I think that could be argued yes - but in order to get the effect I needed in 3JS I needed to use Blender to set each side as an individual mesh


text:
Join duplicated side back on to side duplicated from
I have a bag and a side of the bag that I duplicated - they look like this:

I'm trying to connect the duplicated side back onto the side that I duplicated because the other side of the bag has two faces whereas this side only has the one and .
I've looked around and it seems to be that to connect two objects you have to select a side to delete from each before you can connect them. All I want to do is to add this side back on and connect it to the same vertices it was duplicated from.

"connect the duplicated side back onto the side that I duplicated" - ? Are you sure there isn't any recursion involved? As I've got it you want duplicated face to attach to the adjacent face of the mesh? I don't really think there's a sense in doing that, you can just recreate a face in place. If you really want to attach it you can use snapping, e.g. https://blender.stackexchange.com/questions/20891/how-to-snap-the-center-of-a-face-to-another-face

Unless I misunderstand what you describe you are basically "doing nothing". You duplicate a face and then proceed to merge it back into the one it came from again virtually eliminating it. What have you gained from that, other than lots of extra steps? To be clear if you join them back the duplicated face will disappear leaving you exactly where you were before.

Well if that happened then I'm quite confused as to what to do. I'll need to run through some Blender tutorials then

Thanks Mr Zak - it worked.
In my particular version of Blender (2.77) I first had to select the side - select the Magnet symbol, select the Cube symbol right beside it to select the "Snap Element" (Volume, Face, Edge, Vertex or Increment) and then position it they way it needed it.


text:
How to use Blender in a way that allows easy modifications
I am new to Blender
   I had just made my first 3d print job
question
suppose that my object is made of two basic objects
cube and cone
I had created a few duplications of these basic objects and then used a few union and diff operations.
Now that I got my 3d object printed
I realize that the cube should be smaller
I wish I could have change my first cube size and all other cube dimensions will change as well.
is there a method of work with Blender that allow that?
Thanks
Ori

Try the same thing again. However this time don't apply the boolean modifier on your original object set, just keep them active. You can take your original objects by duplication and hide them on a different layer. This way if you need to make a modification, you can duplicate them back to your working layer, make the desired changes, and on the working layer only apply the modifier(s).
So that you have a bit more visual context to what this means, here is the break-down:
Here are the ways that I split up the layers:
Layer 1 (Homerow 1) = The Active Layer
Layer 2 (Homerow 2) = The Stored Object Being Subtracted From
Layer 11 (Shift + Homerow 1) = The Stored Object Being Subtracted.
Here are the screen shots in the order listed:

Here is the modification workflow after you find the need to change something: