text:
Slow soft body physics causes the animation player to stop
I just started using Blender.
I'm trying to roll a ball running down a long pipe. Just letting the soft body physics run drops down the fps in solid view mode under 1 fps , which causes the animation player to stop.
My guess is that the objects("pipeline") its collapsing with is just to big?! But shouldn't this somehow be an easy job to do?

You need to bake the softbody calculations (cache section in the softbody settings). Without a bake blender is trying to calculate everything on the fly in real time, hence the drop to 1fps.

In your case (base along pipeline) the rigid body system is better suited to do the simulation, since it isn't imperative for the ball to deform.
Nevertheless creating a simpler collision geometry is helpful.

Remove the current softbody and collision settings.
Duplicate the track object. This track_duplicate will be used to create a collision object with less resolution. Remove the wireframe modifier of the track_duplicate and decimate it with a decimate modifier. (I first used the planar option, applied it the used it with the collapse option and applied it again.)
Make the track_duplicate a passive rigid body object and set its shape to mesh.
Make the ball an active rigid body.
Hide the track_duplicate object (it will still be used for collisions) and show the original highres mesh.

You only need softbody object if they're supposed to deform.

i know i should thank you... anyway thank you! Awesome explanation:)

@horn If an answer helped you, you can upvote it. The additional information from your (deleted) answer can be edited in the question, which will bump the thread automatically. If you want a higher playbackrate you could consider caching the simulation or baking it to keyframes.

Unfortunately the current soft body physics solver in Blender is not fast enough to consider it as a usable thing, especially when making animations where the objects in the scene could be pretty complex with lots of polygons.
However, try lowering the number of polygons of your objects and see how much things speed up. Also, in Soft Body Edges settings turn off Edge and Face collision. You may also reduce the number of solver iterations in Soft Body Solver


text:
Rename Operator like F2
I'm working on a task to create the same operator as F2 rename operator inside the blender. I'm stuck at this point because my object names are not refreshing in the operator and also their names are not changing as I'm inputting the value into the string. I hope you understood this because my English is not good enough to explain you.
The thing is my operator is not working properly as it should.
Here is the code:
import bpy

class IMAGES_PT_RENAME(bpy.types.Panel):
    bl_label = "Rename Images"
    bl_idname = "IMAGES_PT_RENAME"
    bl_space_type = 'VIEW_3D'
    bl_region_type = 'UI'
    bl_category = 'Renamer'

    def draw(self, context):
        l = self.layout
        l.operator('flipbook.rename_images')

class IMAGES_OT_RENAME(bpy.types.Operator):
    bl_label = 'Rename'
    bl_idname = 'flipbook.rename_images'
    op_prop: bpy.props.StringProperty(name= '', default=bpy.context.object.name)

    def execute(self, context):
        bpy.context.object.name = self.op_prop
        return {'FINISHED'}

    def draw(self, context):
        lay = self.layout
        lay.label(text='Object Name')
        r = lay.row()
        r.label(icon='OBJECT_DATAMODE')
        r.prop(self, 'op_prop',)

    def invoke(self, context, event):
        return context.window_manager.invoke_popup(self)

classes = [IMAGES_PT_RENAME, IMAGES_OT_RENAME]

def register():
    for cls in classes:
        bpy.utils.register_class(cls)
def unregister():
    for cls in classes:
        bpy.utils.unregister_class(cls)

if __name__ == "__main__":
    register()
```

You want to use bpy.types.WindowManager.invoke_props_dialog

Operator dialog (non-autoexec popup) invoke (show operator properties
and only execute it on click on OK button)

instead of bpy.types.WindowManager.invoke_popup

Operator popup invoke (only shows operator’s properties, without
executing it)

Also, the correct way to initialize an operator property is not in the annotation definition, since at the time the annotation is registered, the context is not yet initialized so there is not bpy.context.active_object. You can use the invoke method to initialize properties.
Don't :
 op_prop: bpy.props.StringProperty(name= '', default=bpy.context.object.name)
Do :
    op_prop: bpy.props.StringProperty()
and then
    def invoke(self, context, event):
        self.op_prop = context.active_object.name

Also, since your operator needs an active object to function, you should prevent the user from executing it if there is no active object.

    @classmethod
    def poll(cls, context):
        return context.active_object is not None

The full script :
import bpy

class IMAGES_PT_RENAME(bpy.types.Panel):
    bl_label = "Rename Images"
    bl_idname = "IMAGES_PT_RENAME"
    bl_space_type = 'VIEW_3D'
    bl_region_type = 'UI'
    bl_category = 'Renamer'

    def draw(self, context):
        l = self.layout
        l.operator('flipbook.rename_images')

class IMAGES_OT_RENAME(bpy.types.Operator):
    bl_label = 'Rename'
    bl_idname = 'flipbook.rename_images'
    op_prop: bpy.props.StringProperty(name= '')

    @classmethod
    def poll(cls, context):
        return context.active_object is not None

    def execute(self, context):
        context.object.name = self.op_prop
        return {'FINISHED'}

    def draw(self, context):
        lay = self.layout
        lay.label(text='Object Name')
        r = lay.row()
        r.label(icon='OBJECT_DATAMODE')
        r.prop(self, 'op_prop',)

    def invoke(self, context, event):
        self.op_prop = context.active_object.name
        return context.window_manager.invoke_props_dialog(self)

classes = [IMAGES_PT_RENAME, IMAGES_OT_RENAME]

def register():
    for cls in classes:
        bpy.utils.register_class(cls)
def unregister():
    for cls in classes:
        bpy.utils.unregister_class(cls)

if __name__ == "__main__":
    register()

Note you can also rename the object directly in the panel
import bpy

class IMAGES_PT_RENAME(bpy.types.Panel):
    bl_label = "Rename Images"
    bl_idname = "IMAGES_PT_RENAME"
    bl_space_type = 'VIEW_3D'
    bl_region_type = 'UI'
    bl_category = 'Renamer'

    def draw(self, context):
        if context.active_object is not None:
            self.layout.prop(context.active_object, "name")

Thank you for this. Actually I'm new to python then I've learned the Blender python recently.

One question, then how does their operator work without the Ok button?

Because they're directly modifying the object name in the popup, instead of the property of the operator, which does work. But as I explained in my comment I wouldn't recommend since it's not really supported and can lead to unsuspected bugs.

class IMAGES_OT_RENAME(bpy.types.Operator):
    bl_label = 'Rename'
    bl_idname = 'flipbook.rename_images'
    def execute(self, context):
        bpy.context.object.name = self.op_prop
        return {'FINISHED'}
    def draw(self, context):
       self.layout.prop(context.active_object,'name') #<-- here
    def invoke(self, context, event):
        return context.window_manager.invoke_popup(self)

Also see sourse Blender F2 operator.

While this seems like a good idea, note that modifying data outside the scope of an operator in an operator popup can cause undefined behaviour or even crashes. For example if your operator poll method depends on the name of the active object and you modify the object name so that the poll now returns falls, your operator will throw an error when you try to execute it.

I did not understand your answer properly I'm new to here.

source: Stack Exchange

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

sort: votes


text:
Is that possible to see the file details in real-time window using ImportHelper
I have created a file browser operator using ImportHelper. What I want is I want to see the selected file details in the same window as I have shown in the screenshot. And the properties should update as I select any other file.

import bpy
from bpy_extras.io_utils import ImportHelper

class test_filebrowser(bpy.types.Operator, ImportHelper):
    bl_idname = 'test.file_browser'
    bl_label = 'Custom File Browser'

    filter_glob : bpy.props.StringProperty(default = '*.mp4',options={'HIDDEN'})
    resolution : bpy.props.IntVectorProperty(name='Resolution',size=2)

    def execute(self, context):

        return {'FINISHED'}
    def draw(self, context):
        layout = self.layout
        layout.label(text=f"Video Resolution: {self.resolution[0:2]}")

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

def unregister():
    bpy.utils.register_class(test_filebrowser)

if __name__ == "__main__":
    register()

You need to use ffmpeg module. https://stackoverflow.com/questions/51342429/how-to-extract-metadata-of-video-files-using-python-3-7

It works fine with VS code but the Blender python console is not working with it
https://i.sstatic.net/7ulNE.png
https://i.sstatic.net/2vW4T.png

Yes, you have to install ffmpeg module inside the blender python module. Read this: https://blender.stackexchange.com/questions/272610/how-to-install-python-module-before-installing-addon

Blender has a separate python lib, so you have to install ffmpeg in that lib so that it can be used in blender's interactive python console or by your addon

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


text:
Is it possible to hide the invoke popup if it is not called? python
My question sounds a bit messy. I do not want to show the invoke popup on the right side of the screen when it is not executed. I have added two conditions in the invoke function in the first condition it will pop up on the button but I don't want it to pop up when the second condition is executed. In the second condition, it is popping up on the right side of the screen that I don't want it.

Here is my code.
import bpy

class CUSTOM_PT_PANEL(bpy.types.Panel):
    bl_label = "Custom"
    bl_idname = "CUSTOM_PT_PANEL"
    bl_space_type = "VIEW_3D"
    bl_region_type = "UI"
    bl_category = "Custom".upper()

    def draw(self,context):
        layout = self.layout
        layout.operator(CUSTOM_OT_OPERATOR.bl_idname)

class CUSTOM_OT_OPERATOR(bpy.types.Operator):
    bl_label = "Adds Cubs"
    bl_idname = "custom.adds_cube"
    bl_options = {"REGISTER","UNDO"}

    def invoke(self,context,event):
        cube_is_there = False
        for obj in context.view_layer.objects:
            if "Cube" in obj.name:
                cube_is_there = True

        if cube_is_there == True:
            return context.window_manager.invoke_popup(self)
        else:
            return self.execute(context)

    def draw(self,context):
        layout = self.layout
        layout.label(text="The Cube is already there in the scene.")

    def execute(self,context):
        bpy.ops.mesh.primitive_cube_add()
        return {"FINISHED"}

classes = [CUSTOM_PT_PANEL,CUSTOM_OT_OPERATOR]

def register():
    for cls in classes:
        bpy.utils.register_class(cls)

def unregister():
    for cls in classes:
        bpy.utils.unregister_class(cls)

if __name__ == "__main__":
    register()

remove UNDO from bl_options

It is not undoing. I want to UNDO also.

use self.report() instead of invoke_popup.

I'll add an operator and some properties in the draw function that I want to hide from others. I already know about self.report().

please clear up your question.

there is a popup because the Cube object is already in the scene.

In the second condition i.e. else condition, there is no popup. share a video

in the else condition there is no pop but it was showing on the right side of the screen. After changing UNDO to UNDO_GROUPED. The right side disappeared.

are you talking about the left bottom undo panel?

In your question Is it possible to hide the invoke popup if it is not called?, why there will be popup if it is not called?

Why are you calling it right side? Undo panel is located in left bottom side.

This question is an oxymoron.

bl_options = {"REGISTER","UNDO_GROUPED"}

I have got the answer from the API documentation. At the bl_options it should be UNDO_GROUPED instead of UNDO.
It is working as I was looking for.
import bpy

class CUSTOM_PT_PANEL(bpy.types.Panel):
    bl_label = "Custom"
    bl_idname = "CUSTOM_PT_PANEL"
    bl_space_type = "VIEW_3D"
    bl_region_type = "UI"
    bl_category = "Custom".upper()

    def draw(self,context):
        layout = self.layout
        layout.operator(CUSTOM_OT_OPERATOR.bl_idname)

class CUSTOM_OT_OPERATOR(bpy.types.Operator):
    bl_label = "Adds Cubs"
    bl_idname = "custom.adds_cube"
    bl_options = {"REGISTER","UNDO_GROUPED"}

    def invoke(self,context,event):
        cube_is_there = False
        for obj in context.view_layer.objects:
            if "Cube" in obj.name:
                cube_is_there = True

        if cube_is_there == True:
            return context.window_manager.invoke_popup(self)
        else:
            return self.execute(context)

    def draw(self,context):
        layout = self.layout
        layout.label(text="The Cube is already there in the scene.")

    def execute(self,context):
        bpy.ops.mesh.primitive_cube_add()
        return {"FINISHED"}

classes = [CUSTOM_PT_PANEL,CUSTOM_OT_OPERATOR]

def register():
    for cls in classes:
        bpy.utils.register_class(cls)

def unregister():
    for cls in classes:
        bpy.utils.unregister_class(cls)

if __name__ == "__main__":
    register()
```

import bpy

class CUSTOM_PT_PANEL(bpy.types.Panel):
    bl_label = "Custom"
    bl_idname = "CUSTOM_PT_PANEL"
    bl_space_type = "VIEW_3D"
    bl_region_type = "UI"
    bl_category = "Custom".upper()

    def draw(self,context):
        layout = self.layout
        layout.operator(CUSTOM_OT_OPERATOR.bl_idname)

class CUSTOM_OT_OPERATOR(bpy.types.Operator):
    bl_label = "Adds Cubs"
    bl_idname = "custom.adds_cube"
    bl_options = {"REGISTER","UNDO"}

    def invoke(self,context,event):
        cube_is_there = False
        for obj in context.view_layer.objects:
            if "Cube" in obj.name:
                cube_is_there = True

        if cube_is_there == True:
            self.report({'ERROR'}, "The Cube is already there in the scene.")
            return {"FINISHED"}
        else:
            return self.execute(context)

    def execute(self,context):
        bpy.ops.mesh.primitive_cube_add()
        return {"FINISHED"}

classes = [CUSTOM_PT_PANEL,CUSTOM_OT_OPERATOR]

def register():
    for cls in classes:
        bpy.utils.register_class(cls)

def unregister():
    for cls in classes:
        bpy.utils.unregister_class(cls)

if __name__ == "__main__":
    register()


text:
Create a printable image from an UV
After reading this, I wanted to do something similar in Blender. I created a cylinder and mapped an image using UV Project with the camera. Now I had something that looked like this:
This is where I got stuck. I need some way to create an image that I could print from my printer, that when wrapped around a cylinder looked like this. The approach I've tried is transforming the cylinder into a plane, but there doesn't seem to be a good way to do this. Here's the .blend

please use http://blend-exchange.giantcowfilms.com/ to share blend files, your link is connected to a nasty ad-network

did you try : Unwrap -> Project from View?

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


text:
How to deal with this edge

Hello everyone,
I have done everything I can to deal with the line in the middle in an attempt to smooth it and turn it into a single surface but not been able to succeed in the end and wonder if any of you wish to take a look at the piece and help me out. It is part of an old object of mine that I worked on a long time ago and I have no idea what I pressed back then!
Despite having asked for help about this issue before, and been reading up help pages such as How to smooth shade an object while retaining hard edges? it has not managed to help me solve  the issue unless I was doing something wrong. No matter what features and tools I have tried using, the line stays and won't go, I sharpen the object or smooth it, the line stays.
Help appreciated :) I will add a download for analysis if anyone wants to take a look.
 github.com/Vemone/Projectss

Please use accept and/or up vote option if answer helped you. Avoid using answer as a comment.

First of all go to Edit Mode, select all and W > Remove Double, than select this edge and Ctrl+E > Clear Sharp.

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


text:
Hair particle system moves position when loading
I am using Blender 2.79b in cycles render trying to create a character model with realistic hair and eyebrows.  I have set up my hair using a vertex group for the scalp, and the eyebrows were placed using the add tool and X mirror.  Standard hair settings;

Hair dynamics unchecked
Velocity settings default
Rotation unchecked
Physics settings default
Render settings default with B-Spline at 6 steps
Display rendered with 6 steps
Children interpolated, display 25, render 25, long hair checked (unchecked for eyebrows)
Field weights default
Force field default
Vertex groups density set for scalp
Custom properties default
Textures default
Cycles hair settings with root at 0.20 and tip at 0 with close tip unchecked

After combing the hair into the position I want, I can render an image and it looks good.  I save the .blend file.  If I close the program and load the file I encounter a few problems.

The hair is now completely messed up and out of position.
Some of the hair parents have moved position, away from the vertex group in random places on the model, and sometimes floating in mid air away from the model.
The eyebrow I placed appears to stay in position, but the mirrored eyebrow is randomly scattered.

Any guidance would be greatly appreciated.

problem is for the sake of performance we can't have same subdivision level in view port and render .

I believe I found the answer to my problems.  In my subdivision surface modifier I had view and render at different values.

Same thing happened to me, only after rendering the disabled Subdivision Surface Modifier, which had its visibility toggled off came back on with its View Settings. Thanks for posting, it was driving me nuts!


text:
Alpha masks with a solidify modifier - objects with no edge?
I am trying to use planes with a solidify modifier and a transparency mask to quickly test the look of different images for a lightbox I'm making. However Im having trouble getting the rim of the object to appear where the transparency is used.
Its a simple node setup:

Does anyone know how to bridge that gap? the fill rim checkbox on the solidify modifier only does the outside edges, not the edges which are formed by the mask (factor in the mix shader node).
To clairfy, it needs to be nice and simple so tha the image can be changed and the model quickly updated without having to model meshes or adjust booleans. but i need that gap closed or it obviously looks funny.
Cheers,
Dan


text:
How do I track the camera while knowing the specs of the camera?
I'm currently tracking footage filmed on a Mavic Pro drone camera. I have all of the specs of the camera, but I'm not sure how to include it into my track. It's also an extremely easy track because the camera does nothing but a simple pan forward over a stadium.
Yet I'm running into all sorts of problems with the FOV and height and it's a bit frustrating. Here are the specs of the camera. How to I put this into Blender so it doesn't assume the info about the camera/change it after I click to solve camera motion?
Sensor – 1/2.3” (CMOS), Effective pixels:12.35 M (Total pixels:12.71 M)
Lens FOV: 78.8° 28 mm (35 mm format equivalent) f/2.2 with distortion of < 1.5% Focus from 0.5 m to ∞
ISO Range: 100-3200 (video)
100-1600 (photo)
Shutter Speed: 8s -1/8000s
Max Image Size: 4000 × 3000
EDIT: To the person who commented, I don't know how to reply but your thread did not help, the camera is not on a tripod, it's a flying drone shot that moves forward.
To make matters worse, my tracks have become less accurate now that I'm trying to do them again. My pixel solve errors are above 10, sometimes going above 90 despite the fact that the tracking markers are sitting directly on the points they're supposed to. I'm very confused.

Does this answer your question? Motion Tracking Tripod with Given Camera Settings

https://blender.stackexchange.com/questions/42329/how-can-i-get-better-results-when-doing-camera-motion-tracking

I'm not sure if you can see this reply, but no. It doesn't help. I edited my post, please re-read it. Thank you for your help so far

Assumed it's just a pan (fixed location) so you'd have to use the tripod option. Sorry, apparently misread. Anyway, each shot is different and and it's hard to guess what your issue is. Suggest upload a few seconds of the footage so we can have a look.

I was wrong, it's not a pan. The camera is flying. I mistook a pan for a movement. I'll upload a video soon

https://www.youtube.com/watch?v=f9q1z8Pwjh0


text:
How to bake Full Render In Blender
I am new to blender, my computer is too slow. I want to bake full render for faster rendering my animation. Please someone tell me how to bake full render.
thanks
There is my project file that I want to bake:
MyHousePlane.blend

welcome! well, you can bake textures (see under render > baking panel) and all simulations (each has its "caching/baking panel)"... have you tried and are not working for you?

Does: How do I bake a texture using Cycles bake help?

And Mr #David I want bake blender internal.

@m.ardito thanks for comment, so I tried but actually I don't know the workflow. I searched on go and also read bender manual  but nothing I got. Please give me some hint.

@Henry Hunter: I tried your model, it seems to have quite basic shapes, no simulations, cloths, someke, displacements, so what you could to is to bake... textures, basically. I don't know how much it could speed up your animation render, but this means you have to tell Blender to pre-calculate materials for all surfaces as a static image, that will be mapped to the surfaces. This is called UV mapping, and it needs some practice (I suggest you to learn on simpler models). You can read about Blender internal baking here: https://www.blender.org/manual/render/blender_render/bake.html.

@Henry Hunter also check duplicate vertices, you have many...


text:
Texture assigned to more than one object renders differently
I've been looking at this question -
copy the size and scale a texture is mapped by, from one object to another - but concluded it's not the problem. The question deals with UV map disparities relating to scale and origin. I believe my problem is different?
I've tried assigning the material this way too: Adding textures to more than one object to no avail.
I have two cubes, one created by duplicating the other and scaling. Both have the same material assigned. The first cube had the material assigned when I duplicated it. I have unwrapped each using Unwrap > Project from view
I've explored whether it's a lighting issue - though essentially by deleting any previously set-up lights and adding some fresh default ones.

Have I assessed the problem correctly? (It's not a material/texture scale/origin issue)
Any ideas what the problem might be related to?

Note: Blender Render
Images below - the stand with the vases on it should be the exact same texture as the wall behind.

Can you show your material and texture panels? Maybe also upload a .blend file to Blend Exchange?

Is the scale applied for the duplicated and scaled object ?

@MrZak You mean scale in the materials/textures panel? I've been looking for differences, but my understanding is that the texture settings don't take object specific over rides.. (I may be wrong). Or is there a scale associated with the object I should know about... can you tell I'm struggling? Thanks for the interest btw

I meant applying scale of the object; you can see its values in the Properties shelf (Transform rollout). See http://blender.stackexchange.com/questions/7298/why-is-it-important-to-apply-transformation-to-an-objects-data

Ooohhh, can't believe none of the tutorials I've been working through have explained this one. I'd have never turned up that question by searching. Thank you @MrZak, you're a good'un.

The object which has another appearence of the texture was scaled in Object mode, while its UV map was left as it was from the original one. Apply the transforms, redo (or change) the UV map and the texture will act in the same way on both objects.
What happens when duplicating unwrapped object
The original object was unwrapped.
Then the duplicate was created. It derived the UV map from the original object, and that UV map was the same as there.
After that the duplicate was scaled to fit the scene specifics.
The difference consists in that the duplicate was scaled in Object mode, and most likely was scaled non-uniformly (e.g. by Z axis more than by X). These transforms weren't applied to the object data. Hence the mesh was different from one unfolded in the UV map, and that's where the difference came from.
Generally, if you scale by one axis in Edit mode, you'll get non-unform texture distribution too. However you will be able to change that by unwrapping once more.
For details about the possible cases when you need applying transforms refer to Why is it important to apply transformation to an objects data?


text:
Blender render black sharp lines with antialias
I made a music visualizer for blender, and added a few things. Inside blender I had this:
I than made a render:
And if you look close enough you can see that there are some black lines on the edges:
I tried using different types of anti-alias and different filter sizes.I tried to remove it and this happened Which has too much sharp edges, but removes the black lines around the player. Is there a way to remove anti-alias only on some parts? I tried to look on this community but found only for cycles

A suggestion - try ticking/unticking the "Transparency" box for those objects with the black lines.  This usually occurs with alpha-layered images/planes however.

At the end I found myself the answer by clicking random buttons and found the answer:
You have to tick the full sample under anti-alias.


text:
How I can make a curvy flat plane for an ankor?
Ι am making an anchor ornament and I want to desighn the curvy part of it:

But I have no idea on how to make this part. What I want is to extrude some sort of flat 3d object out of the background image:

You can either recreate your shape from scratch or use the image: convert it to svg, and convert your svg to a mesh in Blender

Create two curves, the baseline and the profile.
Baseline:
Create a bezier circle, disable cyclic, notice how it changes the shape due to having auto handles, so after rotating it to be symmetric on $y$ axis, switch the handle types to FREE and only then delete the two excess vertices.

Profile:
Just duplicate the object and scale to $0$ on $y$ axis (will translate to 0 height on $z$ axis), then also scale it a little on $x$ axis (can adjust later). Notice how I switched the pivot to 3D cursor, to make the scaling also move it towards the origin (use .D).
Now set the Bevel to this profile:

Subdivide (F9 to adjust the number of cuts), scale, move, adjust curve radius (⎇ AltS or numbers panel) to your (p)reference:

Also see:
I need help with curve modelling

First of all, if you have a clean image of an icon with flat colors like this you can convert it into a .svg and import it into Blender as a curve and/or convert the curve to a mesh.
You can convert the image to an svg with inkscape, which is a free program. Here's a tutorial:
https://www.youtube.com/watch?v=10m_2bPXa1s
Otherwise, if you want to trace this kind of detail there's many way to do it but I'd use a curve.

If you select the vertices and press V->Vector, you get the type with a straight line. Extrude them as if they vertices and place them on the sharp angles of the icon:

You can then select and move the handles of the vertices to make the lines curved:

When you have the outline done you can fill the curve by using those setting on the curve menu on the right and then transform it into a mesh with the Object drop down menu on the left top

Image originally is an .svg and I could not find a way to import it into blender.

Does the main menu File > Import > Scalable Vector Graphics (.svg)* not work for you? This import option is an add-on that should be enabled by default. You can check it, use the menu Edit > User Preferences > Add-ons, type in "svg" in the search bar to find the add-on. and make sure it's enabled.


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UV coordinates are locked from -10 to 10?
I'm trying to make a face which has a texture loop quite a few times. However, it seems that UV coordinates can't be manually edited using the UV vertex fields, outside the range [-10, 10]. This seems like an arbitrary restriction, especially given that right-clicking and dragging the vertex in the editor allows the vertex to be moved outside this range.
Have I accidentally enabled something without noticing it? Is there a way to disable this clamping?
Edit: I should specify that the range is using the normalized mode, not pixel coordinates.

to me also stops at -10, 10 if you just use the slider field but not if moved by hand. guess that is regular behavior. wouldn't know why

In code most UI widgets such as sliders, number fields etc ask you to set min and max values.
In some cases this can be relevant to how the widget behaves (for example, sliders with large ranges are harder to slide to specific value due to display precision).
In this case the limits are most likely arbitrary.
For things like texture looping or tiling, normally this is done by using the vector mapping node in the materials edit to scale the UV coordinates, rather than in the original coordinates.

I was able to get around it by sliding the coordinate to a number larger than I wanted (i.e 33), then I was able to manually edit the number down to 32.


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Audio visualisation
I have created a simple grid with a wave modifier, It looks like this right now.
I want to have the wave be manipulated by audio. does anyone know how i can import audio tracks into blender and have it "communicate" with the wave modifier?
using animation nodes this is how far i came:

Nothing is happening any tips

There is two ways I know.
Set a key on a parameter of the modifier, and use the Bake Sound to F-crurve. But it's really limited.
Or use Animation Nodes which has actual precise animation controls an hu_ge possibilities based on sound.
Actually, in its Bake Sound node documentation, you can see an example setup looking like what you want:

The nodes seem like a great option, but as a newby how do i insert one of these nodes? i just see nodes that correspond to textures

Check the Animation Node link I provided, everything needed is explained there.

I updated my question, do you know what's wrong with my setup?

you forgot to check the Mesh Data in your Mesh Object Output (far right node).

@Juriaan Also, if you are using version 2.1, connecting the edge indices is a must. So, make sure you do.

Thanks guys! i checked the node. and connected the edges and now it works! cheers to you both

1 more thing, while rendering it says: no output node detected how do i fix that>

https://blender.stackexchange.com/questions/42607/no-render-output-node-in-scene


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Issues with intersecting faces and how to unwrap a maze created from svg file
I'm pretty new to this field.I have used a svg file from maze generator to create a maze. On extruding (and applying solidify modifier), I found that several faces are overlapping and intersecting with each other, which is messing up with the textures. Is there a way to fix this? Can the 2 intersecting objects be merged as 1? and how to unwrap the image?

Related: https://blender.stackexchange.com/questions/60660/cut-intersect-edges

The problem you are facing is, that the svg from maze generator is not well suited to be imported in blender. Here the problem is, that the maze is made out of lines and not of shapes. Basically you want to convert the outline of the lines into a shape. This means you have to "clean" it before you can use it.
I tried it with Inkscape (Download-page), which is free to use. But basically you can use any advanced vector-image-editor to do this, I guess.
Using Inkscape, these are the steps which lead me success:

go to Path>Object to Path (or press Shift+Ctrl+C). This will put every line into it's own object.
First select a line in the objects viewer and then press Ctrl+A to select everything else, since it does not seem to select all the lines if not one is selected in the first place. Then go to Path>Stroke to Path (or press Ctrl+Alt+C). This will convert the stroke, drawn by each line into a shape.

With everything selected go to Path>Union (or press Ctrl++). This will combine all created shapes into one.
Now you can save the svg and import it into blender
In Blender you can set the thickness of the walls by changing the "offset"-value in the curve-properties

Then select the curve and press Alt+C to convert it into a mesh
Go into Edit-Mode, select all, press delete and select "Dissolve faces". This will delete all the unneeded triangle-shaped faces.

To delete all unused point keep selected all, press delete and select "Limited Dissolve"

If you have some ugly connections between points, just select all, press Delete and select "Only Faces", then select everything again and press F to fill the faces again.

Now you can extrude your mesh and have a clean maze

I hope I could help!

Thank you so much this solved the above problem. I used a 10x10 maze and i noticed that when we imported the svg it came as two curves and even after completing the steps the maze has two faces on top. is this how it should be?

Yes, (if I understood you correctly), since there are two separated meshes. You can see it if you select one point and then press Ctrl+L to select all connected points.

Hey the method works amazing when I follow it step by step. I have a few doubts though

Since I require a closed maze I added two paths just to close the maze . if i add this step then when I import into blender and convert to mesh. I notice that the dissolve faces doesnt work. If i do a limited dissolve a single face gets divided into 2 triads . I believe the issue rises cause of the extra paths i added just to close the maze. If I delete that extra edge a large part of my maze lose their faces and I have to recreate all the faces by adding vertices and edges at different bends.

this is just my inexperience but when it comes to UV unwrapping the maze is it alright if the  faces dont come as perfect rectangles. assuming I want to add image texture to the maze walls . what would be the correct way to proceed.


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Curve a face according to a model
For one of my project I need to extrude some parts of complex surfaces (ie different curvature on the different axes). What I initially thought was that I could create a vectoriel draving in Illustrator (plane tho) that would fit-ish with my design, then curve them along the "supporting" shape and extrude them.
Unfortunately I didn't find such feature (curve vectoriel drawings) - the curve modifier needing a path, and I couldn t find a way to generate a path reflecting the wished curvature.
For small surfacesn I extrude the svg and apply a boolean modifier to modify locally the vertices of the mesh of the "supporting" shape, then deete the extruded part and extrude the face surounded by the nodes generated thanks to the boolean modifier. But as soon as the form is too big (ie >1/4 of the round piece), this tech does not work anymore...
Many thanks for you help... I m really stuck right now!
Here is the drawing driving my project. I have a model for round part (skull) and I'd like to do the extruded stuffs

I think this one really needs an illustration ( even if simplified ) of a particular example of what you would like to do.

Agree with Robin, this question is very unclear. See https://blender.stackexchange.com/questions/72118/advanced-curving-and-linking/72159#72159

I edited my post with a picture. Sorry for the fuzzy explanation...

The best method will depend on some other constraints.. is it to be printed? Is it for a game? .. etc

Ultimately, it will be printed

Sorry to insist... Is it still not clear?


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Avoid rerendering noise texture on every frame of an animation
I'm creating an animation in which I've used noise texture with displacement modifier for the bumps and roughness of the ground. It looks pretty good, but for some reason the texture on the ground is rendered for every frame, which results in a different ground texture for every frame.
How can I avoid rerendering the ground for every frame?
Here's a screenshot of the node editor and texture window:

are you using Blender Internel or Cycles Renderer?

@HenrikD Cycles Renderer

What is the scale of your Noisetexture? I suspect that it is too fine and float-prezision is rounding differently each time

@HenrikD I'm not using the node editor. I can't see anything like scale in the texture window

Wait what? If you make a Material in Cycles its always a Nodetree, just go into the Node Editor

@HenrikD There's nothing in the node editor related to the noise texture.

can you upload an image?

@HenrikD I've added a screenshot to the question.

Oh thats what you meant with roughness... I thought you where clearly referring to the roughness in the Material Nodes

Noise is a completly random Texture which is not necesserely equal for the same texture coordinate, each time you evaluate it. Use Clouds with very small size instead

Can you elaborate a bit? I'm quite new to blender.

In your Texturepanel you selected Noise. Just select Clouds instead


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Curving an edge of a polygonal mesh in blender
I'm trying to replicate this bat:
https://www.amazon.in/DSC-Scorer-Kashmir-Willow-Cricket/dp/B014R90AJA/ref=sr_1_11?s=sports&ie=UTF8&qid=1544122892&sr=1-11&refinements=p_n_pct-off-with-tax%3A2665401031
This is what I've done till now:

Now I want to curve the edges in a way similar to the reference image. How do I do that?
Beveling the corners isn't what I want. I need the highlighted edge to be curved similar to the path curve alongside it:

Possible duplicate of How to round the edges of this object?

@DuarteFarrajotaRamos I've edited the question to explain why it's not a duplicate.

Use proportional editing. Here is a tutorial. https://www.youtube.com/watch?v=MrNVVHdKd3E&t=1s

Is it possible you've simply got too many polygons at too early a stage to get smooth curvatures easily?
This illustration may not be exactly what you're looking for, but shows the kind of variation you can get from a Bevel modifier and subdivision:

Shows the mesh. A 2-segment  Bevel modifier is assigned, by weight. The weights on various edges are adjusted to increase/decrease the intensity of the crease after subdivision (The lower the weight, the sharper the crease, relative to the base bevel width set in the modifier)
Shows the Bevel modifier applied: what it's actally done
4,5 Show the result after 2x Catmull-Clark Subdivision.

I haven't gone all the way here - you could apply the Bevel, and go in to tweak the topology to remove any residual pinching, etc.

This is clearly the kind of way it should be modeled nowadays: As fewer vertices as possible. Such simple shape shouldn't require 2k vertices to make.


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How to convert lattice-deformed and bone-controlled eyes to exportable shape keys?
I have a rigged model of Thwomp that I need to export to Unity. The eyes are animated using an armature and Lattice Deformation modifier. As I understand it, you can't export Lattice deforms to Unity (in fact, even my bones seem to do nothing after import, but that's a different problem). So what I think could be a good alternative is shape keys, but I am having trouble.
Here is my model, a regular Gary Busey:

Here is what the rig can do in Blender. I would like to have the same capabilities in Unity after export:

Here are the objects that make the right eyeball. The right lattice deforms each of the right eyelids and the eyeball itself. I just realized I don't have the eyelids rigged right now but...baby steps:

Here is the armature. You can see that each eye is aligned to a bone that points towards the target. The parent bone may be superfluous but it is there to keep all the bones together. I would like to keep this rig on export. The single target has the desired effect of making Thwomp appear to be leering, but I can also set it at a far distance if I need him to appear less cross-eyed:

I tried to make shape keys for the right eye with the armature and lattice modifiers still active, but I found that I cannot scrub between shape keys after making them. Applying the lattice modifier and de-parenting the armature after the fact does not help. There is only imperceptible movement while scrubbing the values for the shape keys:

Whatever solution I settle on, it needs to use the existing textures and UVs because it took me 2 days (solid days!) to bake all the textures (read: Diffuse, Normal, Roughness) for this model and the eyes were the trickiest part. This is an original [fan]project and I made all the textures myself (not including the concrete texture, which is a free texture from TextureHaven--and I have since altered non-eye textures to match the UV's at a better scale, which was more tedious work):

I don't think ('THINK'!) animating the texture coordinates is an option for a mapping like this and the deformation would probably be too extreme anyway. But I am open to suggestions if your experience says otherwise.
So, recap:

How can I make shape keys for these eyes and retain my armature?
Is there a variation or alternative to shape keys that I have not considered?
Solutions must be viable with Unity

Thank you!
EDIT: I made some shape keys and they look terrible. All of them use a forward looking direction as a basis and they do not blend well together. The more extreme shapes are unnatural in the intermediary blend value even without other shapes being mixed:

How can I get my character rigged properly for my game??

What's the point here? To reimplement how bones work with shape keys? You could try proportional editing to linearly displace vertices to the right on one shape key, to the left on another, then also top, bottom, and control the angle of displacement with a combination of influence on those shape keys...

What does the lattice accomplish?  Are you trying to change the shape of the eyeball as the eye moves?  You can probably accomplish this using bone scaling and volume preservation, the way bouncing balls are rigged.

Notice shape keys happen after bone deformations, so they can correct wrong bendings etc. Though they're not aware of rotations, simply the vertexes move from position A xyz to B xyz, so rotating eyes by shape keys is never perfect for this, ea a shape key with eye -90 degrees does and value of 1
It Will look terrible at value -1 (it will stretch out a lot on the other side)
Also, the -90 degree bending would shrink the eye and starting to look strange at -45 degrees.
With a lot of coding you could do it in substeps from 0 to -30 to -60 to -90 and 0 to 30 - 60 - 90 degrees repeating it for up and down, and then a lot of code to calculate rotation per focus point.
You'll be coding a lot to get something like that working, thats not the way to make games efficiently.
But looking back at the problems,...
You also seem to be in trouble about the eye shape itself, you like them to look outward, while also don't like that this leaves you with an eye that doesn't fit the shape properly.
My advice here
Well if I were you, I'd tackle this differently, let the eyes roll out
You can create the optical nerves as a slightly horrific 'rope' shape.
You know the snail of sponge bob, eyes lack that put outwards..
So if the central bone moves forward your eyes move in front of it, then they can be spheres. (the player would most likely see it as a sphere if it's a 3d game, an elliptical sphere pointing at you will be seen as a sphere).
Additionally, when this figures awakens you might then literally roll the eyes forward like how a ball would roll.
But i realy want those pointy eyes... (not recomended).
Add another bone in the eyes so you be able to stretch them forward.
This allso allows for adjusting them back to round eyes to better match the object, you be able to invent some new expressions. ;)

Leave your speherical eyes in the character as they are (they don't fit the oval socket), then create a 2 bone chain. You'll use the root of this bone for the general position and the tip of this bone chain for the actual oval deformation.
CTRL+P your eye mesh to your 2 bone chain. Deform (scale) the tip bone, now your eye looks "pressed" but oval in shape. You can scale the root bone for further adjustment. The lower side of the eye + left and right side of the eye socket will not fit perfectly. Consider adding extra bones and deforming your already deformed eye mesh to fit the skull. Please watch this video for extra details.


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How to weight paint character whose mesh is in several [joined] pieces?
Hello all you beautiful Blender-people! I am trying to finalize a character but am having trouble pinning down the bone weights. My character mesh is technically "one mesh" but that mesh has multiple disconnected components. That is, the eyes, eyebrows, nose, mustache, collar, hands and feet are not vertex-merged with the rest of the body. That can be changed for at least some pieces if it must be, but let me describe the problem:

I am getting severe deformations in the collar when the neck rotates (it shrinks to a singularity);
I can get the eyes and the nose to stick to the head when the head bone is manipulated, but not the neck;
Similar story for the mustache.
No matter how paint these components, I run into similar issues.
Version of weight painting that works for all facial features except mustache when NECK is moved, but not the head:

Another version of weight painting that works for all facial features except mustache when HEAD is moved, but not the neck:

What precisely do I need to consider here to make the facial features move as expected? What will keep these components (these are all part of same object) from scaling?
I also have a Youtube video using this rig where I teach people how to mess up their characters (BE NICE PLS b.c. I'm gonna redo it anyway after I figure this out, I'm sure being disconnected pieces is a big part of the problem):
Link to video
EDIT: So I just noticed that the mustache is painted to a knee's pole target, so let's see what happens if I paint that out...

OK!  So, cautionary tale for other animators: If you redo your IK bones 50 times, make sure that each time you uncheck "deform", otherwise good luck figuring out what portions of your mesh you are going to get unwanted vertex weights for. In this example, the IK bones at the heels painted the heels (unwanted), but the pole targets offset from the knees painted only the mustache (for some reason, also unwanted). Beware!


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2.81 preview mesh as transparent?
EDIT: I may have buried the lead with this question. I do not want to use xray mode because that makes everything transparent. I've been away from Blender for a couple of months and just installed 2.81, having previously considered myself a 2.80 guru. Now I am feeling very embarrassed because I can't figure out how to make my meshes display semi-transparent in the viewport so I can see reference images through them. I don't want to make materials, I just want some meshes to appear transparent without putting everything in xray mode.

Press z and then select the option on the left side of the pi menu?

no, that only shows the same display modes as at the top. I am asking how to change a single object's transparency without making materials. You can do this with reference images by adjusting the "alpha" value in the "empty" context menu. I thought it used to be possible to change the alpha in the "object" context menu or the "data" context menu, but even though there is an alpha slider in the object context menu under "Viewport Display -> Color", changing the alpha does not change the appearance in the viewport for any render mode.

You can make your material (semi)transparent in Solid view.
Shading editor > Sidebar > Options > Viewport Display
Suzanne with two materials assigned.
One is opaque, the other is semi-transparent.

I said I don't want to put everything in xray mode. In my case, I am modeling a head and want the eyeballs to be transparent but the head not to be.

Oh, my bad. You can enable transparency in in solid view for your material :). I'll update my answer.

That's what I thought! But it must not be in the same context menu anymore, yes please explain if you know

Hey there :). If this answer solved your problem, please mark it as accepted. The Community bot keeps bringing it up. Thanks.


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How to install prototype glTF export addon/module?
I've read about Installing Add-ons but I still can't get blendergltf installed correctly.  I understand it's an early prototype, but I believe it to be in a state where it can at least install and try a simple export.  I'm using Blender 2.76b.
This addon ships with two files, __init__.py and blendergltf.py.  I made a zip file with both of them, and selected "Install from file..." on the zip file from user preferences.  Blender has dutifully unzipped both Python files and installed them into the correct ...\AppData\Roaming\Blender Foundation\Blender\2.76\scripts\addons folder on Windows.  I have been able to get other (simpler) addons to load from that same folder.
In the Blender system console, I see:

fake_module: addon missing 'bl_info' gives bad performance!: 'C:\Users\username\AppData\Roaming\Blender Foundation\Blender\2.76\scripts\addons\blendergltf.py'

So sure, blendergltf.py is structured as a module, not an addon.  The bl_info definition is in __init__.py which is in that same folder, attempting to load the other script as a module.
Near as I can tell, the module is being loaded as an addon while the actual addon is being ignored.  I must be doing something wrong.  The addon does not show up at all, not even in the disabled state under User Preferences -> Addons tab -> "Testing" category, which is where I would expect to find the checkbox to enable the new addon.
How can I get this installed?

both files need to be in /Blender/2.76/scripts/addons/blendergltf/ folder.  Create a blendergltf folder in addons and move the files there.

Ah, they need their own folder under addons, thanks!  I tried so many crazy permutations but I didn't think to make a subfolder.  I guess my zip file may have worked had it contained a subfolder.  Go ahead and post that as the answer, thanks.

Rule of thumb, multiple py addons with an  __init__.py will have their own folder.  Single py addons with bl_info are installed in addons folder.

This is great info, and I got the plugin working, thanks!  If you re-post this as an answer instead of a comment, I'll accept the answer.


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Refraction bending with planar surfaces in Cycles (2.78b)
I was always under the impression that straight lines should refract and reflect via planar surfaces into straight lines.  Cycles seems not to do this in certain instances.  In the video below you can see it best on the left face at the start and the right face at the end of the sequence. At first I thought it was a problem with my HDRi but it seems surrounding geometry creates the same effect.  Am I wrong in my assumptions, do I have some settings or parameters incorrect in my materials or environment or is this a "feature" of Cycles?

Refraction example on YouTube
Here's the Blend file (slightly edited since this video was made):

Here's a single face of the cube and no HDRi showing the effect.

It's a light feature! When rendering with the default perspective camera, you are correcting the 'perspective projection distortion', which is what happens in real cameras (tipical panoramic distortion). When you put a refractive object in it, you are forcing the distortion to take place in the object location (the object becomes a new focal point!). What looks strange is not the refraction, but the absence of distortion when using a small focal length and the default perspective camera.

This render result is indeed physically incorrect. Can you share your scene and setup? I wasn't able to replicate this with a 35mm camera, a 1.3 IOR glass shader and HDRi. Note that refraction phenomena on HDRi are limited - here is an example: https://i.sstatic.net/egRBd.png

@Jerryno I've edited the question to include the .blend file.  I've removed the HDRi and the effect is still visible.

I think it is correct. For the refraction in the front plane the light is passing through two parallel planes and so ends up at the same angle as originally incident. As the HDR background is effectively out at infinity the parallel rays appear to be unaffected by the refraction. For the distorted "refraction" in the side, it's entering the side, reflecting off the back surface and passing out the opposite side. This means that the rays travel a different distance through the cube depending on where on the side face they hit, producing the 'bend'.

@RichSedman yep, the HDRi does not shift because it's in infinity. Including a close up object (like that window) in HDRi makes the render physically incorrect (that's what I meant with incorrect:). But I am fairly sure if the cube is homogenous inside and the sides are planar you cannot get any kind of bulging distortion.

I've added another image. In this I've removed the HDRi as I think we are getting distracted by that. The cage around the glass cube is geometry in the scene made from a subdivided cube with a wireframe modifier applied.  I've also removed five faces of the glass cube, which I realise creates an artificial situation, and it still shows the issue.  I've done a lot more testing today and feel that there might just be a bug in the way that the refracted ray is interpolated across the interior of the face.  It doesn't look like it is a problem with the normal as a fully glossy shader looks fine.

@PaulMc Yes I came to the same conclusion as you. Tested your .blend thoroughly and it looks like a Cycles bug indeed. Not a normal issue I can confirm. Before posting this I just wanted to compare with other renderers when I get home. If this indeed proves to be a bug it will be a big one..

@PaulMc So it is like this also in LuxRender.

@Jerryno I do think this is correct. I think the distortion is more pronounced the more the viewpoint approaches the plane - so it would be perfectly straight if the viewpoint was effectively at infinity but gets more pronounced the closer you get to the plane. Think of the view from the bottom of a swimming pool looking up. Reverse the refraction (ie, air to water rather than water to air) and the distortion would curve the other way.

@RichSedman There should be no distortion. You see the things behind the boundary as if looking from another location and with different field of view (zoom). A straight line should remain straight line, no distortion possible. This diagram I made should clear that up: http://i.imgur.com/mNUUWqM.png. It's the same with the underwater example: http://img.tfd.com/ElMill/thumb/F0R-07-S2958.jpg. The refraction keeps the lines undistorted: https://ichef.bbci.co.uk/images/ic/640xn/p023hqnk.jpg. Distortion should only happen if the surface is not planar or volume not homogeneous.

@Jerryno I disagree - while the rays are obviously straight, the resulting image viewed through the planar surface is not. Consider this image https://goo.gl/images/XtAlqF  - the edges of the sky is distorted in towards the centre - directly above is not affected while the greater the angle to the normal of the surface, the more it is distorted in towards the centre. Non-radial straight lines would become bent around the centre point.

Here's another image to demonstrate https://goo.gl/images/JLuXkI - assuming that the pool side and fence are straight. The fence posts show the distortion quite well - with the one at the far top-right most obviously affected (assuming it's not due to the ripples).

Well I'm about to concede that I'm wrong.  Tests with POVRay and Blender Internal both show the same effect and if Cycles and LuxRender do as well then perhaps the maths is correct.  I'm guessing that the flaw in my logic is that we are not used to seeing planar surfaces with materials that have an IOR as low as 1.3.  Bumping up the IOR to 1.5 seems to straighten out all the distortion. @JerryNo thanks for the support but I think that for IOR values between 1 and 1.5 this distortion is normal.

@RichSedman, thanks for the examples, they do support this idea.

@RichSedman so I tested couple more renderers and the same results. I did the math and draw the rays in Autocad and the projected refracted rays do not intersect in single point! I used the shnells formula n1/n2=sin(alpha)/sin(beta). All diagrams on web like this one: http://img.tfd.com/ElMill/thumb/F0R-07-S2958.jpg and others are lies. Also what they teach in schools is very simplified.. So the closer the camera is the bigger the distortion. IOR of 1.3 should be fine, water is 1.33.  The distortion is always there for anyIOR, but if camera is further away it disappears fast. You were right!

@jerryno - thanks! I think the school point of view is typically that the incoming rays assumed to be parallel from infinity so I guess that normally avoids the problem. Impressed that you've managed to do the math - it was making my head hurt ;-) Do you feel able to put together an answer for this - I think you're probably better qualified for it and could probably do it a whole lot more justice (for the maths) than I could.

On first look it might seem that refraction on planar surfaces will not distort the image, but just linearly bent it or zoom it:

In real world there are very few examples where the distortion is clearly visible, one of them being refraction on water level:

(Thanks to @RichSedman for pointing this out and patiently making me dig deeper to find the truth and how it works.)
Refraction follows the Snell's law. This means that for every IOR value there exist a critical angle after which the ray won't be refracted but reflected:

We can see this in the above pictures, where the refraction is surrounded by the reflection of pool or sea bed. We will return to this (in Cycles) later. What we also see is the distortion of those refracted rays, so lets tackle the distortion first:
It's best to start with reflection analogy. Reflection is much simpler - the angle of incidence is the same as angle of reflection - their relationship is linear (unlike with refraction). By tracing the reflected rays, we can construct a single(!) virtual viewing point B, from which we see the reflected image:

Doing this with refracted rays (and drawing them in CAD with Snell's formula) reveals, that the rays do not intersect into a single virtual viewing point, but into infinitely many of them (because the relationship between incidence angle and refracted angle is not linear). This means that every piece of the refraction we see from different perspective and that is the reason for the distortion (every 2 rays create a virtual viewing point in different location):

Now let's see how this behaves in Cycles - left how it changes with distance to camera (single refractive quad with IOR 1.3) and right how it changes with IOR (1.0 to 2.0):

This is physically correct behavior. By knowing this you are now able to create a panoramic fish-eye lens camera from simple perspective camera and a refractive quad (if the engine can do refractions but has no such camera option:)
But what Cycles doesn't do on it's own is to change the ray from refractive to reflective after the critical angle just with the Refractive shader (naturally) - it is just black. For this there is the Fresnel node that after the critical angle gives 1.0 mixing factor to mix in Glossy shader:

The glass shader has all this already build in.


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Extrude a mesh by Region using Python script
I've got a flat mesh resulting from a previous script (How to draw a PostGIS Polygon with holes into Blender using Python) :

I'd like to extrude this mesh by Region using Python (This can be done from Blender, in Edit mode, selecting the entire mesh, then from the mesh menu: Extrude --> Region)

Typically, i don't want to extrude individual faces showing the internal edges of the polygon like this :

Below is a script extruding the active mesh, but unfortunately it's using individual faces, and i couldn't adapt it to extrude Region :
import bmesh

o = bpy.context.active_object
me = o.data
bm = bmesh.new()
bm.from_mesh(me)
faces = bm.faces[:]
for face in faces:
    r = bmesh.ops.extrude_discrete_faces(bm, faces=[face])
    bmesh.ops.translate(bm, vec=Vector((0,0,-3)), verts=r['faces'][0].verts)
bm.to_mesh(me)
me.update()
bpy.context.scene.update()

Is there a way to adapt this script to extrude Region instead of individual faces ?

personally I would put a Solidify modifier on the 2d Surface Curve (The closed polyline) then convert to Mesh. Simple script to write if you're interested --- or simply use the Extrude parameter on the 2d Curve. (In Object Properties -> Geometry)

This should do the trick, and no need to create a bmesh object to extrude all your mesh's faces:
import bpy

# Go to edit mode, face selection mode and select all faces
bpy.ops.object.mode_set( mode   = 'EDIT'   )
bpy.ops.mesh.select_mode( type  = 'FACE'   )
bpy.ops.mesh.select_all( action = 'SELECT' )

bpy.ops.mesh.extrude_region_move(
    TRANSFORM_OT_translate={"value":(0, 0, 3)}
)

bpy.ops.object.mode_set( mode = 'OBJECT' )

Often you can find hints about how to call operators from the info panel, and of course the tooltip. In this case they give contradictory hints but both can get be beneficial:

This is exactly what i needed. Thank you so much Tlousky. I didn't know about that info pannel, quite useful. I was on the right track with this extrude_region_move() function but i had trouble passing the right parameters. Prior to that call, I was also missing the face selection mode, and the "select all faces" function. Thanks to your example, it now works like a charm :-)

No problem. Just have to warn the the info panel doesn't always show executed operators, but it's a good habit to check there from time to time.

See

TextEditor -> Templates -> Python -> BMesh Simple
TextEditor -> Templates -> Python -> BMesh Simple EditMode

for an example of how to get the bmesh from an object in Object Mode or Edit Mode.
Here's a low level way to do the extrusion using bmesh.ops.solidify. This example will extrude only those faces that are selected.
import bpy
import bmesh

me = bpy.context.object.data

bm = bmesh.new()   # create an empty BMesh
bm.from_mesh(me)   # fill it in from a Mesh

bmesh.ops.solidify(bm, geom=[f for f in bm.faces if f.select], thickness=0.3)

bm.to_mesh(me)
bm.free()  # free and prevent further access
me.update()


text:
Attribute as Selection
My goal is to use serial of specific list of numbers as vertex selection.
For example if I have a numbers 1,3,17 and I want to distribute instances on a grid at vertex number 1,3,17.
Since I don't see an option to use String node as source I imported CSV text file via addon. It generates an object and stores values as Attribute per vertex. No problem for Loc/Rot/Scale like here, but what about selection?
I can see the attribute (named vertices) is there ...

... but attribute is not seen as vertices by Selection socket.

Ideas how to solve the issue?

maybe i misunderstood, but shouldn't be the selection a boolean than an integer? so if they are all > 0 ...they are all true

Chris is right, since it's a boolean field, it's only looking if they're greater than 0 or not, and they're all positive so it selects all first 7 points. You need to compare the sampled index numbers to the context's (grid). However, while that works for me if I sample a single index, it doesn't when I look at all indices so I'm a bit stumped as well: https://i.imgur.com/k1QQrzj.mp4

@Chris  Thanks for contribution, but I'm and I will be a geonode looser (I do very elementary progress full of pain, so If you want to help just hints are not helping me, sorry ... use answer or screen to illustrate please. Transfer Attribute > Boolean the output is 1 for all.

@Kuboå Thanks for try ... I can't even try it since at home my Mac can't open last Blender 3.4 based on Metal, so no "Sample Index" node available ...

Just a few thoughts 1) your "vertices" attribute is actually the indexes of the verts that your want to select/mark. That means you need to compare these numbers with the index of the grid, which results in a boolean value (true/false = selected/not selected). -- 2) The Transfer Attribute node loops through all verts of the grid (destination) & adds the attribute of the sources mesh. If there are not enough values it repeats the last value. This means you cannot match the indexes because the Index node only gives you the index of the source mesh, not the destination. You need both indexes

@Blunder ad1 thanks, yes, thats what I understood from Kuboå that he tried and failed  ... I was naive thinking Selections reads just a numbers without comparing real vertex number. ad2) I noticed that in Viewer ... any solution on your mind ... Thanks

Sample Index is basically the same as Transfer Att. with an Integer inserted into its Index slot: https://i.imgur.com/bYUBjU5.png Here you can see it's correctly working for a single index, but when you leave at just "Index" it stops working. Interestingly, in the old Transfer Att. node it seems to work like @Blunder says, repeating the last value after it runs out of index: https://i.imgur.com/N7tRQJ6.png but it simply gives 0 in the new Sample nodes instead: https://i.imgur.com/H43Ptco.png It still should work for the first 7 points I feel, but it doesn't. I don't know why.

Last time I was confused about a similar situation I had to ask @quellenform : https://blender.stackexchange.com/questions/264857/how-can-i-re-sort-the-points-indexes-of-an-object-in-geometry-nodes?noredirect=1#comment481949_264857 Maybe he can point to the solution again here.

Can you point us in the direction of the add-on? I would expect the CSV to be something like  , \n  for all vertices.. or you (we) could write your (our) own script..

Here is a very similar question: https://blender.stackexchange.com/q/262146/107598 - the answer was to expand the input set and specify for each vert if it is selected or not. It's the same Robin Betts just suggested. It is a working solution (https://i.sstatic.net/4HMMr.jpg), but very inefficient for a small selection with a large number of vertices. If you select 10 of 1000 vertices you need 10 true and 990 false values. Here is a script that expands the input values (https://i.sstatic.net/2gjAN.jpg). Make sure you have the objects selected before you run it.

https://github.com/simonbroggi/blender_spreadsheet_import @RobinBetts Sorry ... addon was linked in my answer mentioned in this Q ... Thank you.

I was just writing a comment to your deleted A :) in short ... Tired now to test it ... I appreciate your attention and help guys ... Robin - CSV or addon doesn't matter, if you know a way how to feed Selection socket by a bunch of numbers referring to vertex index directly copy-paste or blenders Text editor even better. It sounds to interesting topic in general, but the first impuls was Q mentioned in my Q here.

Hi, @vklidu ! i was doing the washing-up when i realized (doooooooh!) I'd done the whole thing upside-down :) See revision.

@Blunder even node tree looks simple I would like to avoid additional script in process ... And like in comment to Robin, I don't want to you assign to the CSV or Attribute if you think there is easier way to feed Selection socket by numbers. Thanks.

OK, I withdraw my question above (why my setup would work with a single index but not the Index node). After finally having had my dinner my brain started working a bit and I realized that the compare ("Equal") node is not saying "get me the points with these index numbers", it's saying "compare this list of numbers with the indices of my points, going down the list one by one, and if they're the same, select them". Single index works because you write the same one value to all points so it inevitably finds one that's equal to it. Duh.

@Kuboå :) Thanks for investigation ...

You can sample the grid at the indices in the Named Attribute 'vertices', set the Test Vertices object's vertices to those points, and instance on those:

with this result:

Ha ... it took me from a bed now! Thanks ... I went by this way at the beginning, but I failed - so close / so far :) Thanks a lot. Before I leave this topic - Am I right with my comment under my Q? There is not any simpler way to feed Selection socket without addon (to generate attribute from CSV) ... like from Text editor or what ever ... String node?

@vklidu have to sleep on that one... being a bit dim this pm. Maybe our quellenform will come up with something :)


text:
How to Taper a coil?
I created a simple coil/spring using the "Screw" modifier. Is there a way to "taper" the coil so it gets smaller on one end?
Explanation: I created an Xmas tree in Blender. Now I want to add a string of lights to it using a coil. Hopefully it's something that can be done easily.
PS: I'm using v2.79. Still learning/hate v2.80.
My coil:

Some more similar info available here https://blender.stackexchange.com/questions/300548/how-can-i-make-a-half-circle-spiral-slide

Let me propose another solution.
This will get you the christmas tree shape.
It's not perfect, but it's fast.
1) Create a spring using the Screw modifier.
2) Add a SimpleDeform modifier, set mode to Taper,  set axis to Z
3) Adjust the Deform Factor to change the diameter of the spring.

It's perfect and fast!
If you want to create this shape and don't want to deform the pipe, you could do it this way:

Activate the addon called Add Curve: Extra Objects (available by default in Blender). Create a Curve > Curve Spirals > Archemedian.

In the operator panel, find the right setting.

In the Properties panel > Data > Give your curve a Fill > Full, choose the Bevel Depth and the Resolution you want. Convert to mesh if needed.

Very nicely tapered coil/spring indeed.

Do I remember correctly that this primitive is only available if you enable an add on?

Yes you're right I'm going to edit

Thanks for the replies, but it wasn't the tip I needed to taper but the entire coil (top-to-bottom.) Fortunately, I believe I already found the solution:
With my coil selected and placed over my tree, I found a "taper" modifier as part of the "Simple deform" Modifier. For the "Axis, Origin", I eyedropped a branch at the widest part of my tree. I then clicked/dragged the "Deform" value down to taper the coil towards the top. (If the coil does not change, click the "<->" arrow on the "Vertex Group" field.)

Use a Bezier curve spiral instead the use the Radius Property to control the tapering.
After adding the spiral enter Edit Mode turn on Proportional Edit and use the Radius Property to control the tapering.
Select the tip vertex then pressAlt + S to change curve radius, use the Mousewheel Scroll to control the influence radius.

Thanks for the reply, but it wasn't the tip I needed to taper but the entire coil (top-to-bottom.) Fortunately, I believe I already found the solution: With my coil selected and placed over my tree, I found a "taper" modifier as part of the "Simple deform" Modifier. For the "Axis, Origin", I eyedropped a branch at the widest part of my tree. I then clicked/dragged the "Deform" value down to taper the coil (if the coil does not change, click the "<->" arrow on the "Vertex Group" field.) https://i.postimg.cc/yddNMLc5/coil-lights.jpg

The tree is probably a cone and Mugsy wants a conical spring that would follow the shape as if a thread on a reel.


text:
What's wrong with my UV map?
I'm working on texturing a model and noticed the textures looked off. I applied the UV checker as a texture and noticed that there was definitely something wrong with some triangles (but not whole quads).
In this screenshot I've selected an offending area. As you can see, half the quad is "smeared."

What could be causing this? The uv map was generated using UV unwrap after marking the seams.

It is some sort of a uv stretching problem. You can find where it is by enabling "Stretch" in the uv editor:

Blue is what you want, green is okay, and orange/red is really bad.
My guess is that your problem is in this region, but I can't say this for sure unless you post your blend:

Edit:
The problem is that those are N-gons on the side. You need to remove all of the N-gons to unwrap successfully. I just triangulated, then removed the edge cutting across the center to make it a quad:

Then unwrap, and voila.
Here is the blend:

Thanks for the suggestion re: stretching. I've added a link to the blend. The stretching shows up here: link. Overall, there's not much stretching, except on those three panels. But why? The uv for those areas looks like a good fit for the model.
Also, one of the panels that shows the problem is solid blue-- no stretching at all.

Thanks! Is there a setting to warn that an object has ngons and won't unwrap properly?

To check this, go into edit mode, then go to "Select > Select All by Trait". Disable "Extend", set number of vertices to 4, and set the type to "Greater Than". All n-gons will be selected.


text:
After import to Unity, all my normals are flipped
I found someone with similar problem, but their answer doesn't work for me. Other than that, the net is full of advice how to flip normals programmatically to create interiors on the fly, but other than "Your normals are wrong", no help.

All my normals point outwards.
I exported the object to .obj, imported it into Unity, and got:

Did I apply the texture to the reverse side of the faces, or something like that? How do I fix it?

d'oh. I reversed all normals in Blender - so that the object obviously looks all wrong, only insides, no outsides - and after importing the .obj to Unity it works. I wish I knew how to avoid doing silly workarounds like that.

If you found a solution, please remove your question or answer it yourself.

@BillyS: The problem is it's a silly workaround, not a solution.

I see.  In that case, I would recommend deleting the question.

@BillyS deleting a question is not a good choice if there wasn't given satisfactory answer.. it won't help anyone in that case.

@Mr Zak There isn't a satisfactory answer.  Seeing that the issue was that SF made a mistake, and didn't notice it, it would not help anyone anyways.

@BillyS: I didn't make a mistake. I made an object with all normals pointing outwards in Blender, completely correctly. After export, they began pointing inwards in Unity. I went back to Blender, purposefully did the wrong thing: flipped all the normals to point inwards, exported the (silly and wrong) result, and Unity did the same thing as before - flipped the normals again - which resulted in a correct model! It's a "two wrongs making a right" situation.

...actually, I made a mistake - but in a completely different place. My "fix" was really a case of two wrongs (not) making a right, and Mr Zak's info about the negative scale allowed me to fix my original mistake, instead of adding a second layer of wrongness on top of the first one.

My guess would be that your object has negative scale in Object mode. As .obj does not store object transforms, the scale is applied on export and so causes the normals have negative direction as well.
To fix this, in Object Mode hit Ctrl + A  > Scale, then do the operation described in answer you already found (in Edit Mode hit Ctrl + N or Shift + N for 2.8+) and then re-export.

You are right - the scales were all negative That must have happened very early in the making. I just changed the sign on the numbers... normals are still pointing outside, textures are mirrored but that's easy to fix, Let's see if it corrects the issue.

It worked! After changing the scale to positive, normals kept pointing outwards. I just flipped the textures where it mattered (Alt+M, X having the right UV map field selected) and after exporting, Unity loaded the object alright.

maybe answer is out date but CTRL+N does not working for me :( what should I do?


text:
How to get actual rendering progress and estimation from render_stats python handler?
There is render_stats bpy handler
It seem like it is invoked every time rendering engine prints to console smth like
Fra:0 Mem:410.70M (0.00M, Peak 450.46M) | Remaining:01:16:22.96 | Mem:307.83M, Peak:307.83M | _mainScene, interior | Path Tracing Tile 18/8160

I am wondering if  there is a way to get numbers like estimate(01:16:22.96) and current tile(18) from render_stats handler in python script?
Now the only way I see to get this is parsing blender output which is not very cool
There is something alike it in UI, but there is no tooltip with python snippet for it:

This question may seem alike Is it possible to get render time per tile?, and it's stands there that you can't. But in there it's about render time for specific tile, and I am asking about render time estimation for particular frame, may be you can get overall estimation?

there is an addon Render_Time_Estimation in blender you may ant to take a look at the source code

I've seen it, as long as I understand, this particular addon estimates total time for animation rendering essentially based on (total_frames_to_render/number_of_renderd_frames*time_spent_so_far). What I am ineteresed about is how to get estimation from rendering engine for rendering one frame

Related https://blender.stackexchange.com/questions/133114/is-it-possible-to-get-total-render-time-via-python-code

I know it's not the best, but the best I've been able to come up with is code that processes the console output:

Output gives you the render time of the last frame
Output tells you the frame number that was just rendered
You know how many frames are in the complete render, which you can pass to your program
You know the start time of the render

From the above, you can calculate the average render time per frame, which I've found after just a few minutes becomes a pretty stable value.  If the number of rendered objects per frame changes dramatically over time, then of course the average value will change, but given the average render time per frame, you can come up with:

Number of frames which were rendered - grab that from the console
Amount of time elapsed (Current time - Start time)
Current running average render time per frame
Frames left * average time/frame == Render time left

If you have multiple scenes within an animation, you can then also do per-scene calculations, along with the overall animation calculation.
Again, it's not the optimal solution, but it's pretty easy to put together, and it does an effective job of informing you how much time do you have to go before your animation is done.
I hope this helps.


text:
Blender 2.8 compositor isn't saving me any time?
I'm trying to squeeze out some animation highlights for a sizzle reel and wanted to save time by reusing my background with the compositor. Here is what was being rendered before I used a transparent background and set the ground plane to a shadow-catcher. This took about 15 to 20 minutes and have 32 of these to render:

So I saved an image with only the background in it and set up the compositor, thinking the program would either completely ignore most of the background (I set the ground plane as a shadowcatcher) or zip-thru the empty areas, but the square regions are taking just as long to compute empty space!

I followed this tutorial for my setup pretty much exactly, except the image I am using for the composited background is just the ground plane without the character:
https://www.blendernation.com/2017/04/17/use-new-blender-shadow-catcher/
Here is my compositor setup (for some reason the character isn't in the preview but obviously he is being rendered sans background):

What am I doing wrong? How can I save time rendering this image sequence? Eevee is not an option because the shadows don't blend as nice even if I crank up the settings
EDIT: Border rendering result not compositing correctly with background:

The topic of this question is how to save time rendering using the compositor so this is still relevant because using border-rendering WOULD save time if it worked with the compositor. Is there a way to do that? I turned "Crop to Render Region" off because keeping it on was literally cropping the image. But with it off, I have these black regions.

Blender doesn't know the tiles are blank, even if you do, until it has rendered them. More info here: https://developer.blender.org/T34888 and https://blender.stackexchange.com/questions/143798/how-to-not-render-unnecessary-tiles. In short, border rendering may help.

Will rendering with border region still composite correctly? I haven't seen examples of that where the background is put back together with the foreground

Using border rendering is leaving a black region where the image is supposed to be composited with the background, is there a way to fix this?

Try using a color key set to black. That's in the matte menu, as I recall.

I like your Luigi!

@Millard Thanks! <3 :D
https://www.youtube.com/channel/UCVp8kUHIpK3IGgpWjPPV44Q

No adaptive sampling in Cycles in Blender versions prior to 2.83
Cycles used lack adaptive sampling functionality in versions lower than 2.83 so no matter what, the pixels being rendered used to get sampled as many times as there were samples defined in the render settings.
Mask with Holdout shader
You could make a plane, parent it to the camera(Ctlr+p) using Without Inverse option so it snaps to the camera and is oriented to it's local space, move the plane and cut a hole in it so it's sort of a mask. If you assign Holdout shader to it it will get rendered as transparency (transparent film enabled) and it will still get sampled, however those samples are going to be as easy to calculate as possible, so it will speed up the process greatly. You can make any shape of the mask just by modelling the hole the way you need it to be, however if it covers anything that you need in the render(like shadows for example) that will become invisible, so you need to be careful about what you mask.

You can see the masked areas outside the center of the image render a lot faster:

Adaptive sampling is added since Blender 2.83
From version 2.83 adaptive sampling is finally added and if enabled will render transparent areas a lot faster.

It would be interesting to know the reason for the downvote someone gave to this answer.

Wasn't me, I love crazy out-of-the-box workarounds like that. I have to pose another animation tomorrow and will confirm this strategy then. Thank you for this suggestion, I am excited to try it (plus it should be easy b.c. I am using orthographic projection and the camera, character are fixed[-ish] for each animation)

That's a nice trick. Not sure why somebody would downvote this, computer graphics is all about taking shortcuts while making it look as good as possible.

I mean... I honestly hate this workaround and the fact that there is no adaptive sampling in Cycles myself( it samples everything even when rendering masked render layers!), but I think working with what we have, that might be of some help in some situations...

@MartinZ Adaptive sampling is being worked on, not sure if/when it will merged into master. https://developer.blender.org/D4686 the branch is cycles_adaptive_sampling.

I believe there have been talks about it for many years now, but it has never reached official versions that most people, including myself, use for work... :/ It's not in 2.80. It would be great if it came with 2.81, but to be honest even though I am really waiting for it, I wouldn't be surprised if we need to wait longer...


text:
emission lights not working as needed in cycles or eevee
I have this scene that is finally starting to come together but I can't get the lighting to work properly in 2.79 or 2.80 (Cycles or Eevee).  This is what it looks like in the viewport:

I know the dome needs to be optimized.
This is what it looks like in Evee:

The only lights in the scene are emission objects on the windows.
I also have an environment texture that I am trying to use for "HD reflections". As long as the environment texture is plugged-in, the lightning is the same no matter how many, how few, or how high/low I set the emission shader:

If I unplug that environment texture, the scene is completely black (except for emission objects) no matter how high I turn up the emission shader:

I have ambient occlusion turned off.
The blender file is attached (or would be, if I could find the "attach" button (where'd that thing go?). Can somebody take a look at my settings and help me figure out how I can get my emission lights to be usable? As it is now, I can't use them to properly illuminate the scene. Thank you for your assistance.

please use https://blend-exchange.giantcowfilms.com/ for attaching .blend files and make sure you have all the required textures included.

"error uploading". Also, I have 133mb of texture files in a zip, what can I try

All my textures are 4K, made in substance designer (I was planning to downsize as needed). Any ideas on why the upload for the .blend file is failing? it's only 1.7mb. Could it be b.c. it is version 2.8?

Possible duplicate of How to make mesh lights work in Blender Eevee?

No, a moderator made the question say "Eevee"; my problem was that my scene had duplicate shaders and I was updating one that was inactive in the scene. Problem persisted before moving to version 2.80

Eevee isn't a raytracer like Cycles - lights, reflections, shadows, etc. are effectively 'faked' in order to sacrifice quality for speed. This means that you can get lightening fast renders but does require some 'pre-setup' in order to get the desired results - by way of light probes.
Mesh lights (ie, Emission shaders) produce indirect light and by default Eevee doesn't handle indirect light at all.
For mesh lights you need to use an Irradiance Volume light probe. The Irradiance Volume is a cuboid which encases an area of your scene. It is not rendered itself but Eevee can 'bake' the contents to measure the irradience (emission) within that section of your scene, applying it to any other parts of your scene within that volume.
Within the Render properties in the right-hand properties panel is an Indirect Lighting section and within that a Bake Indirect Lighting button. Clicking this tells Eevee to analyse the indirect lighting (Irradiance Volumes and other light probes) which it can then use to render the scene.

Rich, I think you might be on to something important for people who are transitioning from Cycles to Evee. It did turn out That the reason the light intensity did not seem to change at all (regardless of renderer) was that I forgot I had 2 different emission shaders in the scene and was only modifying the inactive one. Deleting the inactive shader and working on the other (while in Cycles) allows the scene to render as expected. Thank you for your help, it saved me some time troubleshooting

If you want to properly show the lighting using Eevee make sure to turn on Ambient Occlusion, Bloom, and Screen Space Reflections in the Renter Properties.
Then you don't need to bake the lights.


text:
Depth Pass to Pixel Projection (AN)
Additional question to 3DSinghVFX's answer

To illustrate question - imagine this white/pink rectangles as rendered image of 6 x 3 pixels.
Here seen by Camera.

Animation Node tree (mentioned in the answer) generates a compact surface.

My question is ...
How can be pixels (reconstructed in 3D space from Depth Pass or Point Position Map as points) represented by unconnected quads orientated to Camera. To be seen by Camera as regular squares without gaps so final result is identical to original image.
In theory, since those faces aka pixels are oriented to camera they are still squares and from mentioned answer also grid is nicely even to a camera view ... So the only question here is probably how calculate size according to distance from camera.

Sidenote: Surface generated by mentioned answer is awesome, downside of that menthod are connections between front-back pixels that are empty space in real. Since there is not a way to store this kind of data in EXR, it seems to be better use pixels as separated to get similar result.

I'm also interested in version with coloured Points (spheres) scaled accordingly to Camera distance, to be seen by camera as same size.

I would appreciate if you can use the same EXR source data from original Q.
Thank you for help.

@3DSinghVFX Now I see I could simplify whole the roman here into a singl question ... how to calculate size according to distance from camera?

@vkidu Hi. Do you need spheres for Point-Cloud and scaled them according to camera distance?

Okay. I have done some tests with spheres, it looks promising. However, with planes to get an exact match with the original image, we have to stretch/shear them accordingly which is difficult.

Very Sorry, I was very busy. There is a way, I'll answer this today.

Method:

The idea is to first compute the distance from the camera for all vertices of a polygon 2) then find the vertex that minimum distance from the camera 3) then project the remaining vertices of the polygon accordingly.

Follow the Method for Depth Map with AN+EN to get this node-tree,

We compute the distance from the camera for all vertices of each polygon then reproject according to the vertex that has minimum distance from the camera. This will give a new polygon(s) that is perpendicular to the camera view,

Now, we have vertices for separated polygons and we can get polygon-indices and edge-indices with the help of the Separate Polygons node,

Blend File:

To add spheres at the center of newly project polygons, first, we have to compute the scale according to the polygon size like so,

Then use Extract Polygon Transforms node to get the polygon transformation and use the Step 4 scale for matrices to instance spheres at the polygons' center,

Blend File:

WOW ... Thanks a lot for your time ... awesome result ... my toy for this weekend. I don't have ambition to understand the math behind ... I would be happy if I will be able to reuse it for my needs :) That seems to be easy.

You're welcome :) This method is performance-heavy. If I find some faster method then I'll add that too.


text:
How can I move the whole leg in Pose Mode?
I'm here:

I would like to move the whole leg. My version in 2.74. I follow a tutorial: https://www.youtube.com/watch?v=kPYbdnPwHuQ.
It's a v2.71 and it's different version than mine. I tried to do it with different options:

Blend File:

your setup is not identical to the one in the video, so it is better to share the blend, eg:  http://blend-exchange.giantcowfilms.com/

@m.ardito I've attached the blend file. thanks


text:
Appending with bpy.data.libraries.load and drivers
I'd like to append all objects from a specific blend file. Some objects in the blend file have drivers attached. For example z-coordinate of the Cube is equal to z-coordinate of the Empty. I used the following simple code for appending.
import bpy

with bpy.data.libraries.load("path/to/test.blend") as (data_from, data_to):
    data_to.objects = data_from.objects

for obj in data_to.objects:
    bpy.context.scene.objects.link(obj)

However, drivers don't work after execution of the above code. They start to work if I go to the driver settings and press "Update Dependecies" button.
What is the trick to make drivers work?
Here is the blend file I'm trying to append:

Well, aside from me having to change context.scene to bpy.context.scene and changing self.filepath to "/var/tmp/untitled.blend", I had no difficulty appending an object with a scripted driver using your script.  The fact that you are using self.filepath is very odd (If I wanted a copy of something from the current .blend I'd just duplicate it).  You may have to upload your .blend, or at least clean up your code example to rule out the possibility that you are confusing blender.

@MutantBob The code snippet was used inside an operator, that is why the code had self.filepath and context instead of bpy.context.scene. I'll update the code, so it works without an operator.

I added a blend file

After testing with the .blend you provided, I'm inclined to call this a straight-up bug.  The question is still totally valid because you need a workaround until the coders have time to fix the bug.

The following code does the trick:
import bpy

# prepare files list for bpy.ops.wm.append(..)
files = []
with bpy.data.libraries.load("path/to/test.blend") as (data_from, data_to):
    for name in data_from.objects:
        files.append({'name': name})

bpy.ops.wm.append(directory="path/to/test.blend"+"/Object/", files=files)

It depresses me that the solution is to use bpy.ops.  I hope somebody can come up with a better answer.

@MutantBob I have the same feeling and the same hope :)


text:
Why is this object completely black while in edit mode?
My object in Edit mode has gone completely black in edit mode, and I cannot seem to correct it.  I was following a tutorial at the Lyndia site working through a UV example, and I never went much further than unwrapping the object, and it did not appear to be the same object the tutorial was illustrating and eventually got to this state trying to remove extra vertices that were showing up.  I also tried to remove the seams, but cannot even add them nom
I am going to start the project again, but I would like to know what happened, so I do not do it a gain unless I need to.  Any help would be appreciated.

Thanks

Can you upload your blend file to Blend-Exchange so that it's easier to diagnose what's wrong?

Blend file uploaded.

I'm not sure why and how it was done, but if you remove doubles (Edit mode > select all > W > Remove doubles) ~ 2000 verts will be removed. After recalculating normals (Ctrl+N) mesh should be good. Still I didn't experienced black mesh - it was slightly different than usual one.

@MrZak That seems to solve it. Care to post this as an answer?

@MrZak I was able to correct the object follow your steps.  I believe the how and why could be largely related to me being new to Blender and my Mac.   At the end I may have tried one to many things before posting the file.   Thanks for the help.

In this case mesh is built with too many vertices and faces serving no purpose for this not complex mesh. Initially it has slightly more than ~2000 polygons which is too much for that.

Select all with A, press W > Remove doubles. It will tell you that around 2000 double vertices was removed.
Select all if not selected and press Ctrl+N to recalculate normals. The model will look as usual from now on.

Read about normals: Why are some of faces in my mesh darker

@RobertRhodes One last thing to add (not related to this problem but important in future) - it's good idea to apply scale in Object mode using Ctrl+A. Read more about that in this post

Thanks for the tips.  Ironically the presenter of the tutorial covered that next.  I am still not grasping the problem, but I will read through your material and keep and eye out for it.  Thanks.


text:
Soft Body hooking stretches instead of moving
I'm trying to animate a soft body in Blender by using hooking, but it doesn't work right. The following is what I do:

I create a mesh - in this case it is an elongated object, like a thread/yarn - and assign its ends to vertex groups. I create a vertex group for both ends too.
I assign the Soft Body physics modifier to my thread, and make settings on it, see screenshot below. Note that the Soft Body Goal is set to the vertex group of both ends of the thread.
Then I go into edit mode, select the vertex groups of either ends individually, and then assign a new hook to them with Ctrl+H.
Then I give some keyframed translation/rotation/whatever to my hook, and I expect that the soft body I made should follow it "as a whole", moving and stretching accordingly and preferably realistically.

However, instead of this, what happens is that the hook pulls the vertices of its hosting vertex group, and stretches the faces connected to it, but the rest of the object doesn't react.
In the Modifiers tab I tried various settings, like specifying both the hooking Object and the Vertex Group, and hitting the Apply button; or not hitting the apply button, just leaving it like that; or not specifying the Vertex Group. None of these work.
Could you please point out what I'm doing wrong?
These previous posts didn't help (I could only post here one):
Rig a rope spanning two objects

The order of the Softbody and Hook modifiers in the Modifier stack is important. For the soft body physics to take account of the hooked vertices it must be positioned below the hook modifiers in the stack. Performing the steps in the sequence in your question (create mesh, add Soft Body, set Vertex Group, add hooks) adds each modifier at the end of the stack so that the Soft Body will be first, followed by the hooks. ie,

Note the Soft Body above the hooks.
This will produce the following results (note that I've added Skin and Subdivision Surface modifiers to make it more visible) :

The modifiers are applied in 'top-down' sequence and so for the Soft Body to take account of the hooks it must occur after the hooks have been applied. Simply use the arrows (at the top-right of each modifier panel) to move the Soft Body to below the hooks and all should be well. ie,

This can then produce the following result :

Note that the only difference between these two results is the order of the modifiers in the stack.
Blend file included