started animation render- how to stop it without losing what has been rendered so far? I have been rendering a 4000 frames animation and it is still going for 3 days now. Can I stop rendering and retain the mov. file (for the part that has been rendered) without risking to lose all the render? this is because I need to submit the animation even if it in progress or partial ..

I don't think it's possible, that's why using jpg instead of movies is convenient, you can stop and relaunch whenever you want. Also, as said by Thibsert, "if Blender or the computer crashes, you don't loose the rendered frames. And it allows multiple computers work on the same animation (using a shared folder and the "placeholders/don't owerwrite" settings)".


How to make a cone UV projection? I can't figure out how to make a UV Projection with a Cone. I tried Sphere, Cube and Cylinder projection too. Can somebody help?

In "Edit Mode" select The bottom vertices and one edge and mark them as a seam by pressing CTRL + "E" and selecting mark seam from the drop down menu. Then in the UV Editor while in "Edit Mode" select all of the vertices
and unwrap them by pressing "U" and selecting Unwrap from the drop down menu.


How can I make the Bishop's hat in the chess piece? I have attached a blender file below along with some pictures. I tried to use the boolean modifier to do the same but came up with rather difficult to work with results. I want to have the curve and the shape of the hat to be nearly the same as the real Staunton Bishop.

gdrive link to blend file: https://drive.google.com/open?id=1x1poqr1abMpW_miAbRIkWpvRVR0twlMc

First close the top of the mesh, then put the Boolean modifier above the Subdivision Surface and use a shape like this one and it seems to work fine.  When you're glad apply the modifier and bring some corrections so that the mesh is clean: Quads instead of ngons, bevels to sharp the edges, etc...


Purging unused data from Python I found a lot of solutions for deleting unused data. Most of them are not practical for my case.
I have a very long script and during this, I want to purge all the unused data from the memory.

I'm trying to run this script but I keep getting errors:

import bpy
bpy.types.SpaceOutliner.display_mode = "ORPHAN_DATA"
bpy.ops.outliner.orphans_purge()

The error:

RuntimeError: Operator bpy.ops.outliner.orphans_purge.poll() failed, context is incorrect

Any suggestions?
Note: I can't reload blender; it's a long and continuous operation and can't be interrupted and if I ignored purging data the memory will leak.

override = bpy.context.copy()
override["area.type"] = ['OUTLINER']
override["display_mode"] = ['ORPHAN_DATA']
bpy.ops.outliner.orphans_purge(override)

you can call every operator with a dictionary in its call in first place (if there are more than one attributes to pass). this dictionary holds the information you want to override from the normal context. you dont have to name the override like this, any other name will do, too.

the thing is, i cannot help you a hundred percent, because I dont really know which parts of the context you have to overwrite. at least in 2.8, "area.type" and "display_mode" are not part of the original context, so you are trying to override something which isnt there, so the context still stays the same like without overriding at all.

i also dont know what you do have to overwrite, because right now i really dont have time to figure that out, sry, I am myself only learning all of this. you can however see whats part of the original context if you type following into the python console:

override = bpy.context.copy()
override

it will list you everything that is in the original context, maybe you find out what you want to overwrite.


Why Does Quad Topology Not Always Result in Correct Shading? Why does quad topology not always result in correct shading? Sure on a cube like this its easy enough to toss on a weighted normal/autosmooth, but why does this happen, and is there any way to rectify it through better topology?

The only thing comes to mind is the software tries to preserve data.
be it smoothing data. until you change it manually it tries to keep it that way.
So that's means more control to you and what you create.
Edit: here is an Image from https://github.com/fedackb/yavne

You could also say software does not know what you want and just does the default calculations.
depending on what you want I would say every artist would prefer one of them over the other.


Problem in unity, my faces disappear when i exporting my truck object or another from blender to unity some my faces disappear in unity. I add some images for better understanding.

enter image description here

Select all the offending mesh in edit mode and in Shading tab select Normals: "Flip Direction". Your model appears to be facing the wrong way, so when backface culling comes into play you can only see the inside. I hihgly recommend you press N in 3D view and enable Shading: Backface Culling.


What does 'Mark Sharp' *actually* do? In the course of teaching myself Blender, I've always been led to believe that marking edges 'Sharp' had an effect only if used in concert with the Edge Split modifier. But then I saw a couple of tutorials which used the 'Sharp' Edge Data property without splitting edges.

The objects below are identical. Autosmooth is enabled for both at 60 degrees. Both have had a Bevel modifier applied to all edges but the ones in the curved section, controlled by weight. The only difference between them is that the one on the right has had its sharper edges marked 'Sharp'

And after the Bevel modifier is applied, there are split vertex-per-face normals on the marked 'Sharp' version, again on the right. The vertex count in both versions is the same.

The Blender manual goes no further than to say the 'Sharp' property works with the Edge Split modifier.. but no Edge Split modifier has been assigned. Can anyone explain what marking 'Sharp' actually does, under the bonnet, contrary to all the explanations I've heard?

According to the v2.92 manual (emphasis added):

The Sharp mark is used by the split normals and the Edge Split modifier, which are part of the smoothing or customized shading techniques.

So, anything that uses split normals can also use the sharp data.  This applies to the Auto Smooth feature of meshes.
Per the manual:

By default in Blender . . . a sharp edge is always defined as an edge being either non-manifold, or having at least one of its faces defined as flat.
Enabling the Auto Smooth setting adds an extra parameter to define a sharp edge, the Angle threshold between two neighbor faces, above which the edge will always be considered as sharp.

So, for example, you could apply Auto Smooth, say at 30°.  Then you could mark an edge as sharp, say an edge that was only 20°.  That edge would stay sharp thus overriding the Auto Smooth.


Particles unaffected by force fields I'm trying to create a water scene where paper lanterns rise from the background (similar to this scene from the movie Tangled.

I'm using a particle system to generate a bulk of lanterns to rise from behind some (really bad for now) hills. The issue is that they just won't budge in the face of any type of force field. Can anyone tell me what is going wrong here?

I set up another file and emulated the situation and things are working perfectly, so I must be making some dumb mistake that I can't see with my tired eyes.

Link to .blend file

In order to make lanterns being affected you should increase the mass of your particles and decrease the Gravity in the Force Field settings.

Clear the Effector Group

First thing to change is to clear the Effector Group in the Field Weights options (or create another group from the force fields). From the wiki:

  The Field Weight Panel allows you to control how much influence each type of external force field, or effector, has on the particle system.

Thus the effector is the one who affects on the particles, not the one who is being affected. And in your file, the group which contains meshes and lamp was set as effector.

Increase the mass of the particles

In the Physics scroll increase the mass of the particles. As they were too lighweight they began to fly away immediately.


Weird Color appearing in sculpt mode Good Day,
I was just modeling a face in edit mode and as soon as I went into sculpting workspace to smooth by model a bit, I noticed a weird color on two of the face

On top of it, as soon as I clicked on the faces to smooth them, they changed color from pink to yellow

BLEND FILE: https://pasteall.org/blend/8b767a2e2a0945b49e96da4639fd14f7

the answer to that is "face sets", it has actually already been answered here:
part of the mesh become yellow when in sculpt mode


How to make a wiggly animated curve? I'm trying to make a curve move in sort of a worm-like fashion, and I'm not able to get it to move properly with F Curve modifiers.  Basically, I want it to move in a looped "s" shape pattern.  How can I achieve this?

This is the pic; the curves are the yellow beam and the electric forcefield wrapping around it.  I used displacement modifiers for the ripple effect.

Basically, I want to animate the curves in an s-shaped pattern like in Ghostbusters:

Good ol' fashion hook modifier.

One way to set up a hook.

Snap 3d cursor to control point of curve in edit mode, then in object mode add an empty.  With the empty selected, shift select the curve return to edit mode,  and "Hook to selected Object" (from space search).

Now you can animate the position of the hook to manipulate your curve.  Adding more hooks will give you more control.

Pretty crappy gif, but you get the idea.  The empty is hooked to the right control point of the default bezier curve. The empty is animated to rotate and follow a circular path.


How to use Geometry Nodes on vertices with rotation? How would I distribute geometry following the rotation of the source mesh, but keep the distribution on the vertices (not random)?

actually i found solution it was blender 2.93 alpha with this nodes


Can an animation sequence be muted? I am working with a scene in which I have created multiple animation sequences for demonstrating the workings of mechanical assemblies and how they are put together. When playing back one of these sequences, I want the others to be inactive- can that be done in Blender? When you have multiple simultaneous animation sequences in a scene, can you select one of them for playback?

Yes an animation sequence can be muted.

In the dopesheet/action editor window you may click on the speaker icon to mute the action.  This is the simple use.  The speaker icon is very small, please look closely.

The speaker icon can be toggled active or muted.  There are also other ways to activate or inactivate an animation.

The image above shows the dopesheet/action editor window type in the upper left. The blue cube has been animated.  You may simply click the speaker icon for simple cases and be done.  When the speaker icon is muted the animation will be muted.

Read further only for more advanced use.

For more advanced use you may use two window types.

By using the dopesheet action editor window and the NLA editor window.
By make active and inactive the animation action.

The image above shows the dopesheet/action editor window scrolled to show the action name .... and the button [Push Down]

The Blender user can click the button [Push Down].
The Blender user can switch to NLA Editor window type.

In the above NLA window we see the action with speaker active icon next to it indicated with an arrow.  Look closely it may be difficult to see.  The active icon can be clicked on and off.

In the above NLA Window the speaker is in the inactive state.  Look closely.

Blender:

version 2.74 (sub 0), branch b'master', commit date b'2015-03-31' b'13:39', hash b'000dfc0', b'Release'
build date: b'2015-03-31', b'15:46:51'
platform: b'Windows:32bit'


Press ctrl+alt+0 to explodes My character I just want to modify the composition of the camera.

But i Press ctrl+alt+0 to explodes My character

here is a video that shows the problem: https://youtu.be/0UgAtkNy1dE

here is the .blend file: https://www.dropbox.com/s/2k9mj85dm8ok3ha/perona06_02%20af%20%20with%20automatic%20weights.blend?dl=0

The problem is that you have inadvertently set part of your mesh to act as the active camera. This can be easily done by selecting an object and pressing Ctrl+Numpad0 - and it means that when you are trying to move the “active camera” it is pulling your mesh and rig apart, causing the distortion.

To resolve this simply select your actual camera and press Ctrl+Numpad0 to set that as the current active camera. Ctrl+Alt+Numpad0 should now be back to moving your actual camera rather than the mesh.


How to keep the gradient when joining objects? On the left, the petals are separate (linked) objects.
On the right, they're joined into one object - but the gradient type changed.
How to keep the same gradient type when I join the petals together into a single object?

(Edited using the provided file)
To keep the gradient when joining the petals, you can use UV coordinates.
Then just project the UV map from top and join.

(To get the same UV map, just select the petal and UV > Project from view)


Draft angle and undercut analyses Is Blender capable of producing draft angle analysis and undercut analysis with STL files? I see that it can produce a heat map for wall thickness, find overhang faces, etc., but I can't seem to find anything for draft angle and undercut.

Any help appreciated.

In the 3D printing game it would be called the 'self-support angle'.

This setup assumes that the upside of your STL/mesh is oriented in the +Z direction.

The example is targeted at a 3D printer which behaves as follows:

prints perfectly up to 30 degree angle (white colour)
in most cases manages to print in angles between 30 and 45 degrees (yellow colour)
anything over 45 degrees will collapse

The ColorRamp can hold values from 0 to 1 while the Normal is 0 to 90 degrees.

Value 0 = 0 degrees
Value 1 = 90 degrees

As a result for this example:

Value 0.333 = 30 degrees
Value 0.5 = 45 degrees

See a nice comparison of how the self-support angle affects the 3D print (note that it is measured from horizontal surface rather than vertical direction in this photograph :/).


Volume scatter without rendering the volume object Below is an uncomposited version of my Earth render. You can see the light haze around the edges. That's the atmospheric scatter sphere that's a little bigger than the Earth itself. Once the light passes through it, it affects the surface of the Earth resulting in this nice orange color around the edges of the day/night transition. The problem, however, is the white haze around the edges of the planet itself are sharp and in order to affect the surface color, the atmosphere scatter sphere must be on the same layer, therefore, I'm unable to blur it slightly.

This is the atmospheric scatter layer on it's own. I've tried duplicating it, moving the dupe onto a new layer behind the Earth and then blurring that to help hide the sharp edges but it's still not ideal, especially when up close.

Here's the finished composite. You may say "It looks fine". True, but this is at a distance and my project requires a gradual descend close to the planet.

My question is, can I still have the atmosphere scatter mesh affect the surface whilst not being a part of the render itself? Can it affect the light off camera, so to speak?

Render Layers:

1) Atmosphere Mask (Uses the 2nd layer(Earth) to mask the atmosphere mesh which removes noise)
2) Earth (Includes a Surface mesh, Cloud mesh and Atmosphere Scatter mesh)
3) Atmosphere (A different atmosphere volume that creates a blue outer glow) <-- Irrelevant to problem

VOLUME SCATTER NODE SETUP:

SOLUTION:

This is the best I could do with risingfall's answer. In order to get the light to change the surface I can't fade it as much as I'd like so from a far you can't really see the fade as much but it's miles better than before, I believe.

Sorry if I'm not picking up on your situation exactly, but is your atmosphere scatter mesh using a volumetric shaded material?  Is it only shaded by volume, or is there also a surface component?

If it is helpful, and if your volume scatter mesh is volume only, I can tell you how to add a gradient to the volume density.  That means you can make the edges of the volume scatter effect fade out, rather than be abrupt.

Here is a two-sphere setup where the volume scatter sphere does not have the gradient:

Here is the same with the gradient enabled:

Hope this helps!


Extrude edge loop along the 'average edge normal' direction I have a following setup: a curve aligned to one of the main axes (e.g. z), so every vertex of that curve has z = same value. I want to extrude and offset the new vertices along the direction locally given by the average normal vector of the two adjacent edges projected onto the plane of the curve (gives two options, I want to be able to choose the direction) by the same constant offset so the resulting thickness is the same. I know this must be possible mathematically, because when I choose two adjacent edges, change the transform orientation from global to normal and move in 'z' direction, it moves exactly according to the average normal of those two edges. I hope this would be possible for individual vertices and their two shared edges.

I hope this picture demonstrates what I want...

Here is how it works for two adjacent edges...note that the vertex in the middle gets displaced along the exactly correct direction, which is the average direction of the normals of the two edges next to it. However, the vertices on either end are in slightly wrong direction...

Is this even possible? Did I miss something obvious in the "Extrude region and move" menu? I also tried solidify (which also warns the user that faces are needed for useful output) and bevel, none of which produced the desired effect. Thanks.

Two possible workflows I can quickly think of.

Select all edges in Edit Mode, press F to make a face then inset it with i. Deal with the leftover "closing loop" in the end manually.

Just convert the edges into an actual Bezier Curve object with Alt + C > Curve from Mesh, then from the Properties Window > Curve Object Data Geometry > Bevel add a second curve as Bevel Object comprised of a single edge in $XY$ direction.
Make sure the main curve is set to 2D to get consistent width, and control width with either Curve Radius, directly adjust the bevel object, or with a Taper Object.


finding a link or material pointing to a missing file or path In packing a blend file I get a report of 3 missing files (actually, only paths) from an FBX imported from a 3dsMax export:
Error: Unable to pack file, source path 'C:\Users\James\Documents\3dsMax\projects\architecture\scenes' not found

(aside: this path actually exists)
I am not getting any console output in 2.90 for "List Missing Files".   Is there some way I can discover what material or other file pointer are causing these errors so that I can correct them?

In the outliner choose the Orphan Data display mode

To fix the path for broken links or missing items use the Data Api mode

Data API
Lists every data-block along with any properties that they might have.
Orphan Data
Lists data-blocks which are unused and/or will be lost when the file is reloaded. It includes data-blocks which have only a fake user. You can add/remove Fake User by clicking on cross/tick icon in the right side of the Outliner editor.

(from the blender manual)


How do i display the Collapse Menus checkbox in a Python menu? The right click Header menu at the header is a C menu. I want to display the content in a Python menu. Like the View menu of the Text editor.

I can grab the operator, create my own class to execute it. And that way i can display the Flip to Top button. And it is fully functional. But how do i display the Collapse Menus prop with its checkbox? layout.operator is functional, but doesn't display the checkbox state. And layout.prop gives errors since i execute an operator, and don't have a prop involved here yet.

My problem is how the things needs to be connected, how the prop should look like. I cannot create a new prop here, it already exists. Or am i at the wrong track here? Maybe there is a direct way to grab this prop? As told it's a C menu, not Python.

The vital code parts are also marked green in the following screenshot:

class VIEW3D_MT_testheaderflip(bpy.types.Operator):
"""tooltip"""
bl_idname = "view3d.headerflip"
bl_label = "header flip"
bl_options = {'REGISTER', 'UNDO'}

def execute(self, context):        # execute()
    bpy.ops.screen.header_flip()
    return {'FINISHED'}
...

layout.operator("view3d.headerflip", text="headerflip")

Not sure how to expose the property that indicates whether the header region menu is collapsed or not. You can however add the bpy.ops.screen.header_toolbox() operator to the view menu.  This is the header menu that pops up when right clicking in Header.

Notice I've appended / prepended to the view menu class, rather than, (.. the slippery  slope of), editing the UI py.

import bpy

def header_toolbox(self, context):
    layout = self.layout
    #layout.operator("screen.header_flip")
    layout.operator("screen.header_toolbox")

# prepend to 3d view view menu
bpy.types.VIEW3D_MT_view.prepend(header_toolbox)
# append text editor view menu
bpy.types.TEXT_MT_view.append(header_toolbox)


Is there a way to make slight imperfections on a model? (golden ring) Im using blender to create jewellery, as you know jewellery is finished with a high polish so that the surfaces are almost mirror like, this is easy in blender but in the jewellery trade nothing is quite perfect, every surface has very slight imperfections and things this is how you separate a render from an actual ring, is there a way to recreate this? I have not yet found any normal maps with the right imperfections or any other method that recreates such a subtle yet important change to the mesh? All ideas welcomed.

You could sculpt a high-poly version and bake the normals, but I guess the easiest way to do it is to fake with a procedural texture. Here is a chain of nodes that works in my opinion: Texture Coordinate (Object output) > Mapping > Vector input of a Noise Texture > Height input of a Bump > Normal input of a Glossy > Material Output. Note that you can play with the Noise Texture node parameters to make the defaults bigger or smaller:

Also, if you want some more or less glossy surface parts, you can plug a Noise Texture node into the factor of a Mix Shader so that it separates 2 different Glossy shaders.


Where is the Blender ID add-on preference pane? For some reason I seem to have lost all my Blender Sync preferences. I reinstalled the add-on which was missing, but the preferences pane is asking me to log in:

I cannot find out how to log in, I restarted after installing, and looked in all the preference panes but didn't find it.

How does one log in with their Blender ID to use Blender Sync?

You need to activate another addon called Blender ID authentication. You put your credentials in the Blender ID addon and automatically the Blender Cloud addon will login


Orientation perpendicular to Edge I have got a mesh that's converted from curve. It has only edges. I need to successively orient one of the objects in the scene to the direction pointed by the blue arrow in the illustration above (perpendicular to the edge and in the direction of the normal of the hypothetical face, formed by the planar vertices). How do I calculate the orientation using python?

a simple cross product solves your problem:

\begin{equation}
\hat{z}: the \space unit \space vector \space along \space z \space axis\\
\vec{e_\perp}:the \space vector \space perpendicular \space to \space edge \space and \space the \space z \space axis\\
\vec{p_1}:position \space of \space first \space vertex \space in \space world \space coordinates\\
\vec{p_2}:position \space of \space second \space vertex \space in \space world \space coordinates\\
\vec{e_1}:vector \space along \space edge\\
\vec{p_2} - \vec{p_1} = \vec{e_1}\\
\hat{z} \times \vec{e_1} = \vec{e_\perp}\\
\vec{e_1} \times \vec{e_\perp} = \vec{desiredDirection}
\end{equation}

you can use mathutils's Vector library to do this.


How is real-time rendering different in blender from game engines? Real-time rendering is the key feature of game engines like Unity and Unreal. Although advanced rendering by Cycles should take a while, I think Eevee should be able to deliver real-time rendering.
I created a simple SoftBody simulation (the official example) with all default settings. By the game real-time rendering standard, this simple animation should be as fast as 30 FPS.
The first playback with Eevee was as slow as 1-2 FPS (GPU was not used). Full rendering by Cycles was as slow as 0.1 FPS (utilising two GPUs).
I have 16/32 cores/threads and two 1080Ti.
Do I miss something? Can we get real-time rendering (30 FPS) with blender?

Well, Blender isn't a game engine, and it's not designed to perform final animation renders in real-time the way a game engine does.  The design goal of the EEVEE renderer is to provide real-time or near-real-time previews and fast (but not real-time!) high-quality final renders.  As mentioned on the development page, it uses gaming rasterizer techniques to render quickly, but it is not a gaming renderer itself, and it targets high quality final renders that aren't subject to a fixed frame rate.
So, for the soft-body example above, you should be able to easily achieve a 30 FPS render in preview mode (with full PBR-like materials and lightning, even without baking the physics, since the physics aren't very complicated), demonstrating that EEVEE can, in fact, render animations in real-time by cutting various corners, but the final render with default settings will be higher quality and quite a bit slower (1-2 FPS seems about right).  I don't think Blender exposes a sufficient number of settings that would allow you to perform the final render at the same speed as the preview.
You could request such a feature (basically a checkbox to reduce the final render quality to the preview-level quality), but I don't think there would be much interest, because most Blender users aren't looking for real-time final renders; they just want fast previews.  That's because they're either using Blender to develop assets for true real-time game engines (and so just need a fast preview to see what they're doing and have no intention of using Blender for the final render), or they're planning to render a high-quality still image or fixed animation and want to prioritize render quality over render speed.


Animating parts of an object Hi is it possible to rotate part of a mesh but without any stretching (I understand weight painting a little) For instance I want to be able to animate just the radar dish around the z axis. Is this doable and is there a fast way such as through a vertex group?

Two (of many) ways to do it:

Select the radar in edit mode and press P to have it separated in a new object, and animate the whole object, without even the need of an armature.

Or

Create an armature which has a "Radar" bone, parent (Ctrl P) the mesh to the armature and choose "with empty groups" option, then in edit mode select all vertices of the radar, select in the properties panel the newly created "Radar" vertex group and click the "assign" button.


Hdri sky background too close? I'm using an image for the background, but I only see a blue sky and not the clouds in the bottom of the image near the horizon. It feels like the background image is too close? And in the world tab the preview is just blue. Should I not see the clouds also?

If I create a scen that are 10x10 meter or 100x100 meter or 1000x1000 meter in size, how does Blender set the correct scale or distance between the scene and the background?

I can rotate the background, but can't find any clouds. And I have tested different settings in the Environment Texture node, but all I can see is blue background or very close to the sun. I get this problem often with this type of images, and I don't know what I am doing wrong? Have I missed some kind of settings?

Other types of hdri images, that look spherical, I have no problem with. But this image looks more ordinary. Preciate some help!

Look at this anatomy of an HDRI image:

This is how things will be mapped. So your clouds are mapped below horizon.

The texture's aspect ratio should be 2:1. Anything else and things will be placed in wrong places unless you correct with mapping vectors (correcting epirectangular mapping could be tricky).

Looks like what you have is just the top hemisphere, but you are mapping it onto both hemispheres. The easiest fix is to edit the image itself and add the bottom by extending the canvas with black.


Can't get my icosphere to render as a halo Not sure why I can't seem to turn my selected object (icosphere) to a halo when I try to make a new material.  The options just aren't showing.  Thanks]1

You are using Cycles Render mode. Switch it to Blender Render and the options you want'll apppear.


Using unity tree editor with blender trees I have made some low poly trees in blender render without the sapling add-on and the only problem is that when I import it to unity and add it to the tree editor and then place it on the terrain it only show half of the tree and the other half under the terrain.

NOTE the two trees in the back were manually placed and the two trees in the front were placed using tree editor and the materials for the trees are the standard

I want to know make the whole tree visible while still using the tree editor. I don't know if the problem is within unity or blender, help will be appreciated.
Thanks in advanced.

Every object in Blender has a center point or origin for it's local coordinates in the 3D view

It is generally represented by a large orange dot by default. You have to have this into consideration when modeling.

Your tree's origin point is likely placed a the center or the tree instead of the trunk base.

Change this either by moving it's gemetry in edit mode so the center is at the bottom of the trunk, or place the 3D cursor where you want the center to be (for example select a face press Shift + S Cursor to Selection) and then exit Edit Mode and press Shift + Ctrl + Alt + C and choose Origin to 3D Cursor


Prefetch frames works only at opening blend-file? On opening a 2.91 Blend-file in the video sequencer, I can see that the "prefetch frames" kicks in. A small orange line starts from the playhead and keeps going until the cache buffer is full (I assume). Previewing the video (for that range) runs then very smoothly. However, after that initial prefetch, it seems that the cache is dismissed and/or not renewed and that the prefetch doesn't kick in any more. Previewing the video becomes then very slow.
I have tried to switch the prefetch option on and off, or changing the field "Recycle up to Cost" (default 10) but that doesn't help. I'm not sure what the "strip cache option" (per strip) does in surplus, but it also does not reset the prefetch frames option.
Am I missing something here? Is there any up-to-date information about the VSE caching (aside from https://developer.blender.org/D3934)?

Changing the cache limit size or the cache type (use disk cache), Ctrl+R (or Alt+R) does not reinitialize the prefetch cache. The only work-around so far is saving the file and re-open it. At that moment the prefetch kicks in, the little orange stripe at the bottom keeps growing from the play head and (after a while) the preview runs smoothly again. This keeps on working until you change something in the timeline. Then the orange cache bar dims out and the performance drops to a much lower frame rate. Apparently, this is also the case in version 2.83 and 2.90.


Using two GPU video cards Does anyone know, how can I check if I am using my two video cards?

It seem Blender is using only one of them. I have checked both on the user preferences settings. But reading temperatures in GPU-Z it seems Blender is using only one of them.

The first card card is Titan X maxwel and the other is GtX1080 TI pascal.

Please give guidance, I bought this new 1080Ti to speed up the render but is not helping much.

The easiest way to tell if it's using both cards is if you see two tiles being processed simultaneously when rendering.  I have three cards processing this scene and you can clearly see the little orange corners on each of the tiles:

Also, I'm sure you already know this, but in addition to checking the User Preferences, make sure you have GPU rendering enabled in the Properties Pane:


Mesh A changes after joining it to mesh B so im tring to make my first character and everything was fine until i made the hands and when im done with it i tried to join it to the rest of the body (Ctrl+j) but whenever i do it be smoother/changes the color or whatever you want to call it
(i applied all of the modifiers before so there are none)

so i got 2 questions

1. how can i fix it?

2. why it changes\what is going on?

Before

After

I too dont understand why the smoothing is happening. But you can fix it by clicking in the flat option, and flat shading should be applied to the whole object again. Maybe someone else can explain what is happening.


rendering partial mesh object I am rendering a shoe by stitching its parts and displaying on the browser, as shown in the screenshot.

How this works is, a python script reads the blend file containing the shoe model, and spits out each part of the shoe as a .png file. This is again stitched back at the frontend. I am however having a problem while rendering the shoe in certain angles at the frontend, for instance the back-view angle as shown in the below image:

For this angle, I want the part SHOE-FRONT rendered partially as shown in the screenshot below, so that there is no overlapping when these images are stitched and displayed to the user in the browser.

It is however, getting rendered as shown below:

This is creating a overlap between the SHOE-BASE and SHOE-FRONT when displayed in the browser. This is just one use-case. Similar kind of issues exist for every angle of the shoe displayed. I want my blender python script to render the mesh models in a partially visible manner, only those that is visible to the user when viewed in a given angle. Can this partial rendering of a mesh object be achieved with blender python scripting? I tried playing with transparency and alpha modes. But no luck.

You can use a combination of

Render Layers
Object ID
compositing

These posts helped me to accomplish a simular case:

How to use an object as a mask?
How can I move an object on a separate layer behind another in the compositor?


Why does pressing 'Numpad .' not center my view correctly on the selected object? In layout mode, when I select my object and press numpad . to center my view onto my object. Instead it has me orbit nothing and I cant zoom in on my object. this function still works for other objects in the same scene.

In your Layout or Modeling viewport, drag out the 'Item, Tool, View' menu from the top right hand of the viewport (has a tiny little arrow pointing toward the viewport, usually to the right of the x y z orientation gizmo). In that drag-out menu, select the 'View' tab and check the 'Lock to Object' text box. If there's something listed there, hit 'X' to the right of it. Now it shouldn't orbit around another point. At least, that was the genesis of my numpad - . issue.


A better way to composite one video sub-clip over another with chroma key? What I want is to chroma key a short segment from one video strip (a title overlay in the middle of a longer video), over another video strip background. I can't see any compositing options in the Effect Strip and Strip Modifier menus except for alpha/mask operations. So looks like I need to generate an alpha on my own, and apply it that way.

However, the only chroma key I am aware of in Blender is in the scene compositor. So the only solution I've been able to come up with is create one whole scene dedicated just to the  title overlay clip, use the Matte output from the Chroma Key node to render the grayscale matte to disk, then reimport the render into a strip in my original scene and use that as my alpha.

This works, but it seems like more steps than there ought to be. I'm used to editors like Final Cut Pro that let you generate mattes via modifiers on a per-strip level. Is there no simpler way to achieve the same thing?

At the very least, can I do something to avoid having to manually render the matte frames?

You are right, you would:
1. use the chroma key source as a single input node then generate a key with the keyer node. This scene will appear in the VSE as a strip with an alpha channel

add an Alpha Convert node set to "Straight to Premultiplied"
Add the scene strip to the VSE timeline on top of the background strip. Check its blend type and make it "alpha over" instead of cross or replace.

You should then be able to trim it to length as required. Remember that to get audio you would have to add the original source strip to the VSE timeline of the compositor scene. But this only works in the latest versions of Blender.

Otherwise you will have to sync the sound up to the scene strip.


Image Texture Node, Clip Image I would like to make a decal in Cycles.

When I use Clip in the Image Texture Node then the background is black. I would like it to be transparent.

The manual (https://docs.blender.org/manual/en/dev/render/cycles/nodes/types/textures/image.html) says: Clip
"Clip to the original image size and set all the exterior pixels values to transparent black."

What the hell is transparent black? Is it black or is it transparent? How do I get the background image to show through the "transparent" black?

This is my setting:

Maxx, like this? That makes the Logo Black. The Image has no alpha information.

I did not get it to work with the transparency shader but it seems to work when I just attach the Alpha of the Logo (although it has no alpha channel, I believe - it is just a jpg) to the Fac of the Color Mix Node.


How do I have an exception to a material override? I tried to have this clay look to my model, and I used the material override to have all materials look like the default white. Works fine, but I would like to highlight the building I'm working on.
Is there a way to have everything the default white color except for that building only?

You can use the Pass Index to indicate to the material how to treat specific objects in your scene.
For those objects you want highlighting, set the Pass Index to a specific value (in this case, '1') :

In your material, use the Object Info node to get the Object Index and compare it to determine how to shade your object (in this case I've used the result of the compare to choose between colours in a MixRGB node) :

This produces the following result (with the cube set to index '1' and everything else left at index '0') :

To change the highlighted object, simply update the Pass Index to disable the previously highlighted one and enable the new one.


Information about the side of the mirror (left or right) while using mirror modifier? Is it possible to obtain the information node (with value 0 or 1) about the side of the mirror modifier?

For example, I have a mirrored object and I'd like to have the possibility to use one set of textures on the LEFT side and another set on the RIGHT side of the object.

Let's say I'm using Mix Shader and have two different Diffuse Shaders plugged into it, the first with right side textures and the second with left side textures. I'd like now to have something that will give me the information (0 or 1) that I could plug into the factor socket of the Mix Shader. 1 would mean LEFT side and 0 RIGHT side (or the contrary, it doesn't really matter).

Is it possible to obtain that information somehow?

you can select one part of the mesh by using a two-tone texture with halves along the axis, in this texture the x axis have the red tone, meanwhile the y axis have the green tone, in this way you can either select texture U ,V or both that provides the mirror modifier.

In material you put the above texture in the red node, in node green you use the node group setup of the second panel, and you must place the UV "mesh" in only one halve. With this node-setup you have the information of U texture or V texture, and you could also work with symmetrical or asymmetrical textures, like the example, in the blue node you have a symmetrical texture, meanwhile in the yellow node you have an asymmetrical texture.

UPDATE

Apparently there's no need for an auxiliary texture, the blend file with the groupnode is here http://pasteall.org/blend/index.php?id=46015, set 0-1 for bypassing the symmetrization of the UV coordinates, set 1-2 for U texture, set 2-3 for V texture, set 3-4 for U and V texture symmetrization. The node also gives you the mask of each coordinate.


Strange shading on surface. Normals facing right way, no double faces, no double vertices I can't find the solution to this one; I don't know the correct name of the problem. The shading is different on parallel faces facing the same direction.

I've tried:
 - Recalculating Normals
 - Removing doubles
 - Tried smooth and flat shading
 - Deleting and remaking faces
 - Adding Edge Split modifier

Any ideas?
Thanks

Edit: Link to .blend:

You have autosmooth enabled, you just need to disable it:

Since your objects have all triangular faces, what you see is the result of auto smooth shading which enhances those triangular shapes.

edit: to other readers benefit, I'll add that as (again) @Mr Zak pointed out, the real reason for this behavior should be "custom split normals" created by the external application from which it was imported this file in Blender.

below an image showing how to remove those custom split normal data (I couldn't find it before), and the effect on 3d viewport shading. After clearing that custom data, the "autosmooth" limit angle data is enabled again, although it is not needed at all in this case.


Weird artifact in blender render I'm trying to recreate a spa water bottle, to get some Blender practice. An example of the bottle:

Around the bottle are some round carvings. I created these with a Difference Boolean with a torus. I've hidden these torusses (tori?) from the view and renderer.

However, when rendering (with Cycles Render), I see some weird shape, like one of the torusses isn't really hidden. When looking with the rendered viewport shading in 3D view, I don't see the extra torus (which is what I expect).

What could this be?

Modifiers applied to the bottle, in order: subsurf, 8 booleans, solidify.

The rendered view (with unwanted artifact):

The viewport view:

EDIT:
I've doublechecked all modifier visibilities and the visibilities of the torusses themselves, and I don't see anything odd. See the image below.

Additional info, I made the torusses by extruding a circle over a circular beziercurve, and creating a mesh from that.

EDIT2:
I've added the Blend file to the top of this question

The problem is caused by a small discrepancy between how the booleans are applied on a level 3 subdiv and a level 4 subdiv. Drop your render sub-div level down to 3 or move the torii so they create the correct behaviour with level 4 subdiv enabled in viewport.


code under modal operator gets executed only when mouse is moved or a key is pressed i have the following code to receive serial data from arduino and rotate the cube...

import bpy
from bpy import context
import serial
from time import sleep
from bpy.props import IntProperty, FloatProperty

value = 0
i=0
j=0
degree = 0
ser = serial.Serial("COM77", 9600)

class ModalOperator(bpy.types.Operator):
  bl_idname = "object.modal_operator"
  bl_label = "Simple Modal Operator"

x = IntProperty()

def modal(self, context, event):
   if ser.inWaiting()>0 :
        value = ser.read(2)
        print(value)
        self.x = int(value)
        print(self.x)
        self.x += 1000
        degree = self.x * 3.14/180
        print(degree)
        bpy.context.object.rotation_euler[0] = degree

   if event.type  == 'LEFTMOUSE':
       return {'FINISHED'}
       ser.close()

   return {'RUNNING_MODAL'}

def invoke(self, context, event):
    if context.object:

        print("hi")

        context.window_manager.modal_handler_add(self)
        return {'RUNNING_MODAL'}
    else:
        self.report({'WARNING'}, "No active object, could not finish")
        return {'CANCELLED'}

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

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

   register()

# test call

bpy.ops.object.modal_operator('INVOKE_DEFAULT')

the code under invoke function executes immediately when i run the script..but the statements under modal function executes only if i move the mouse or press any key...

I think it doesn't consider incoming serial data as an event...

i want the serial data to be read as and wen it comes...not only wen the mouse is moved..

Is there any way to check serial event....  like  'MOUSE_MOVE'  or 'LEFTMOUSE'....

What you are looking for probably, is running a timer alongside the modal operator, so you can check the serial data whenever the operator gets executed with a timer event.

There already is a code template in blender, that shows you how to do this.
Look for the Template menu entry at the bottom of the Text Editor and select Python > Operator Modal Timer

The relevant code is in the execute function:

wm = context.window_manager
self._timer = wm.event_timer_add(0.1, context.window)

The 0.1 controls the time interval between successive timer events in seconds.

Then you can check for a timer event in modal with:

if event.type == 'TIMER':

And for cleanup in the cancel function:

wm = context.window_manager
wm.event_timer_remove(self._timer)


Part of my model won't show in cycles Render I have been working on this mesh for a while now and finally got around to rendering it.

However when I attempt to do a test render the feet wont show in the render. I double checked to make sure that it will show to the camera. And verified that it isn't hidden in render.

It shows in object view

However not during render

I'm not really certain what else I should attempt to do.

Here is my blend file which you can use.

Mech.blend

Set duplication in object panel to none, you have set it to group. When the duplication is active the parent doesn't render


Rough transparent Plastic Material I am trying to recreate the FN P90 submachine gun. I followed a tutorial on modelling and UV unwrapping. Now I tried adding procedural Textures to it.
As you can see, the clip is made up of a rough transparent plastic material:

The clip is a model with an inside with correct normals so the refraction works. On here I saw others use a mix shader with some Gloss and Diffuse to make it less glassy. But that did not really work. Is my factory to high? Here is the shader I used:

For basic materials like plastic, glass and metal, you only need Principled BSDF.
Rough plastic has similar properties as rough glass.

Transmission = 1
Roughness = 0,2
That's it.


Render entire scene normals I'd like to render a normal map for an entire scene (for a large background for an isometric game). I tried exporting the "Normal" pass of my render layer, but it's not quite right. Here's what I get from a cylinder:

For comparison, here's more what I (not to mention the game engine) was expecting:

I've seen tutorials on normal maps, but they are all about baking one object's geometry onto a simplified model. Is there an easy way to render a normal map for an entire scene, to line up with the standard combined render?

Got it! As I thought, Blender's normal pass contains exactly the right data, but it's not in the right format.  From a video intending to use the normal pass in After Effects' "Normality" plugin, I found that it's easy to convert Blender's colors to the standard colors using the node editor:

(This node setup is for Blender Render, not Cycles. For a Cycles solution see this answer.)


Can not edit object after failed Normal Map Bake Using Blender 2.79 I am attempting to create a ferret to animate.  The body has been created in two versions. Both low poly and high ply objects which are located in the same space.  The low poly has been UV unwrapped.  I was trying to follow https://www.youtube.com/watch?v=BOYRCI-dtjU to bake a normal map of the high poly object to apply to the low poly version.  I selected the high poly and low poly objects, set up the bake controls as instructed and hit BAKE.  This came back with an error saying NO VALID SELECTED OBJECTS.  I went back and fiddled with various controls for a while with the same results before giving up for the night and closed Blender without saving.

When I opened it today to try again I found the hi poly version can not be opened in edit mode or seen in the 3Dview. Cycles Render shows it just fine.

Any ideas what might have gone wrong and how to get back into the hi poly model?

The file can be found at WeTransfer

Opened the file again and hit / in the number pad a couple times.  This was one of the first things I tried but for some reason this time it took.  The high res. object can be edited again and I was able to bake a Normal Map. The Normal Map pointed out some problems that need fixing but everything seems to be working again.


Where can I download older versions of Blender? I was trying to re-download the original Blender 2.8, however it goes directly to the 2.81 download page instead.

How can I access downloads for previous versions of Blender and installers for older releases?

Accordoing to the blender.org fortunately "Your old files are safe, every Blender release is available for download. Forever." Just go to the download site and look for previous versions at the bottom of the page.

2.79:
https://www.blender.org/download/previous-versions/

2.80:
https://download.blender.org/release/Blender2.80/

Every build:
https://download.blender.org/release/


How do I use a UVmap in renderman for Blender? I am trying to render a model created using cycles in Renderman but the UV map doesn't show up.  Can anyone help me use the uv map please?

The UV maps work the exact same in Renderman as they do in Cycles. However there is something to be aware of.

You must have the image texture node loaded with the image to view it in the UV editor. (Do not have the node connected to anything just have it in the node editor by itself).

Also make sure you click "convert cycles materials to renderman materials" in the materials tab. (They wont copy exactly but it will get you started).


Black spots in render view, while material view shows correctly This is my model in material view:

This is how it looks like in render view:

As you can see, there are alot of black spots.

Why is this the case?

The problem occured because the object has multiple UV-Maps and the wrong was selected for rendering:

I was able to solve it by clicking on the camera symbol of the correct UV-Map.


Extrude face along normal, following connected edge (extend geometry)? I want to extrude a face in Blender along its normal, but I also want the vertices to follow their connected (but not selected during the extrusion) edges.  This means that the vertices would move relative to one another (in planes other than their extrusion direction), and extend the original geometry by extrapolation.  Another way to look at it would be to "slide" the vertices along their extrapolated, connected, and deselected edges.

This is difficult to describe in words, so let me provide an image.  Here's the face I'm extruding:

And here's how I'd like the vertices to move (viewed from above to make it clearer):

Is it possible to do this in Blender?

In face select, they will only extrude along their normals. In vertex select you can direct the extrusion where you want. And lets you do combinations like E-S-Y-Shift Z or whatever you need.


Geometry Nodes. What to enter in the result to get a change in the Z axis? I entered scale to control the size of the object, if I want to control its height, what should I enter? I tried dozens of different ways.

I guess one solution to do what you are asking is a tree like the following:

Click to enlarge
The logic behind this is simple, use a  separate xyz node, and use a math>add before the combine xyz node to control scale in the transform node.
The value node simply provides a means for uniform scaling in all or multiple axes.
This produces the following result on a point instance of cubes.

Do note that the geometry nodes project is a work in progress, and some features are still being adjusted as development continues.


How to bend/create nice angle without warping model So I am doing some self learning by attempting to copy a phone stand that I have.
I am really close but I am not sure I understand how to create that triangle followed by a really nice bevel.
I have tried just doing a rotation but because it rotates by the center of what I select it just warps the model really badly.
Here is what I have so far:

Thingiverse model
Here is a picture of what I am attempting to copy. (I am not worrying about the bottom angle/bend)

As you have V angles, you should not have modeled rectangular angles in the first place, it's better to first follow the whole shape:

Extrude:

Give it a Solidify modifier (Complex mode to give it even thickness):

Apply the modifier, round the angles with bevel operations:

Correct the topology with the knife (K to activate, Z to cut through), dissolve unwanted edge loops with CtrlX:

Give your object some Boolean modifiers in order to cut of the holes, etc:


I have two edges that intersect, how do I get a vertex at the intersection point? I tried adding this edge with the knife tool to no avail, it won't add in the desired vertices. Is there any other way to add these vertices and have them connected to both edges like the ones above?

blend file

Currently knife would be good to use. For this particular case, there are some tricks to do it even faster:

Trick 1:

Select all intersected edges, then P > Selection;
Press Space to quickly search for Knife Project tool.
Switch to Object Mode, delete the separated object (edges).

Trick 2:

Select the n-gon face while using Face Select mode, then switch to Vertex Select mode to quickly select related elements (or simply press A to select all elements in this case);
Hit Space to search for Split by Edge tool;
Select the two vertices on that horizontal edge, then press J.

P.S.:

There are some addons that are aimed to split intersecting edges, such as zeffii's X ALL, nixy's Boolean 2D Union, even the powerful Sverchok can handle some situations. they all got pros and cons, however. IMHO, We really need an internal tool to perfectly handle it (something like an enhanced version of the current Split by Edge tool).


CUDA, 3D Hardware & Nvidia driver, my Blender goes crazy First I want to say that yesterday everything worked fine for me.
Let's start.
When I launched the blender this morning, I saw this:

I very quickly found a solution to this problem (Blender Can't detect 3D hardware accelerated Driver), did everything as written, but now the program has begun to slow down very much. It is impossible to work.

I reinstalled blender. Did not help.
I downloaded a new driver for the video card - and oh, a miracle! - It worked! But not for long. After a couple of minutes, everything hung and again does not work.

So, right now I have 3 condition of Blender 2.79b:

do nothing = "Can't detect 3D hardware...."
download opengl32.dll = slow down, no CUDA

installed a new NVIDIA driver = everything is fine, but only the first couple of minutes, then closes and error again (about 3d) or freezing if opengl32.dll in folder .

Disconnected Intel(R) HD Graphics - did not help. What else can I do?

System Info: Windows 10 Home, x64, Intel(R) Core(TM) i7-7700HQ CPU @ 2.80GHz, 16 GB, NVIDIA GeForce GTX 1050 Ti, Driver 411.70

So, the problem was in NVIDIA driver. I downloaded an earlier version of the driver(391.25 instead 411.70). I think I will not update them for a long time.


My textures are rendering transparent and strange I am trying to make this cool minecraft effect on blender. I've done all the modeling and tracking. In rendered view it looks fine.

But it comes out very weird. I am using blender 2.8 for this project. It has nothing to do with the materials, because I changed them around and tested it out. I have a feeling it has something to do with either the movie clip editor, sequence editor, or the render settings.

I've been trying over and over to fix it. While it renders it looks fine, but as soon as it finishes, it comes out with nothing but rendered shadows, but I have not enabled shadow catcher. I have done research and I don't think it is a common problem. If you can help me, please do.

This was the default setup of the compositing nodes.

I deleted all of the nodes, and simplified it. Use Alpha over instead of Add.


Export multiple objects to .obj It is possible to export all object from a scene into different obj files (each object in a obj file separately)?

There doesn't exist a way to do this in the options of the obj importer so what you could do is run a script that loops over the items in your scene,
check if it is a mesh and export the current selection to its own file relative to the path your blend file is saved.

import bpy
import os

# get the path where the blend file is located
basedir = bpy.path.abspath('//')

# deselect all objects
bpy.ops.object.select_all(action='DESELECT')

# loop through all the objects in the scene
scene = bpy.context.scene
for ob in scene.objects:
    # make the current object active and select it
    scene.objects.active = ob
    ob.select = True

    # make sure that we only export meshes
    if ob.type == 'MESH':
        # export the currently selected object to its own file based on its name
        bpy.ops.export_scene.obj(
                filepath=os.path.join(basedir, ob.name + '.obj'),
                use_selection=True,
                )
    # deselect the object and move on to another if any more are left
    ob.select = False

To further tweak your export options, see the parameters that
bpy.ops.export_scene_obj() accepts.
For example, you can include normals with use_normals=True, change forward axis with axis_forward etc.

There are more stringent checks that could be made but for simple use cases and if used properly, this should suffice.

Also see How to batch import Wavefront OBJ files?.

To have it export only selected objects, comment line 7 and change line 11.

# remove
bpy.ops.object.select_all(action='DESELECT')
# change to this where instead of the entire scene, we only look through selected objects
for ob in bpy.context.selected_objects:

or keep line 11 and add another line

for ob in scene.objects:
    # add the check to see if in selected objects here
    if ob in bpy.context.selected_objects:
        # adjust indentation
        ...
        ...

NB: Make sure the layers you have objects on are selected otherwise you will just get an empty file.


Focal Length Using Cropped Sensor Cameras When matching real-world camera shots/footage, I need to know whether the Focal Length in Blender represents the focal length set on the lens or the "true" focal length, taking into account a cropped sensor, e.g. Nikon DX.

For example, using my 50mm lens on my DX sensor bodies, the effective or "real" focal length of the images is actually 75mm because of the 1.5x factor.

Thanks.

Yes, I if you set the sensor size to the Nikon DX preset, the field of view should be the same as a real camera. The field of view is computed from the dimensions of the sensor and the length of the lens, as is in the real world.

A 75mm lens on a full sensor camera (24x36mm sensor size) would cover a field of view of 26.9 degrees.

A 50mm lens on an APS size sensor (23.6x15.8mm) would cover afield of view of 26.6 degrees.

Remember that the 1.5 factor in real life is "approximate". The exact match for a 75mm lens would be a 49.34mm lens.


Different camera settings for different render layers? I have a scene with two objects.  I need one to be rendered with the camera set to Perspective and the other to be rendered with an Orthographic camera.

I've put them on separate render layers, but it seems there can only be a single camera for both render layers.  Is that true?

What's the best way to achieve this?

You can have multiple cameras, but only one can be used at a time.

As a workaround, you can use two scenes.

Move the object to be rendered in Perspective to the first layer and the object to be rendered in Orthographic to the second layer.

Go to the Layers tab and select Layer 1 to be rendered.

Create a new scene by clicking the + in the Info Panel:

Select Link Objects.
In the new scene, select the camera and press U> Object and Data to make the camera's transforms and settings independent from the original scene.  Then set the camera to be orthographic in Properties > Object data > Lens.
Still in the new scene, go to the Layers tab and select Layer 2 to be rendered.
Set the background to transparent by enabling Transparent in Render settings > Film.
In the composite nodes (for either scene, just keep in mind that they are independent so it's easiest to keep all the nodes in one scene) duplicate the Render Layers node and pick the other scene:

You can now combine them however you want using the compositor. E.g. with an Alpha Over node:

In this render, Suzanne is in orthographic and the rest is in perspective.


'No Such File or Directory" Error When Working with Shared File I'm attempting to open a file on a Linux computer through file sharing. The file is stored on a Macbook Pro and both computers are running Blender 2.77. However, when I try to open the file on the Linux computer, I get an error of, "No Such File or Directory." I don't think this is a file permissions error as my permissions settings are set so that "Everyone" can read and write my file. What can I do to solve this?

No such file or directory" is somewhat common when

the file needs something else to be processed by the software you are working with (missing shared library for blender, missing linked file with textures, materials...)
the file doesn't exist (or at least it doesn't exist in the given directory)
the filename or the path consists of characters that cannot be read by linux

I assume that you have already used blender on linux successfully (eg opened a local file), so the first point is not the cause of the problem.

Permissions between operating systems are not as easy as it sounds. Both Apple and Windows tend to use some "magic" in their approaches of an easy-sounding task. So it's good to verify the permissions on OS level.

Try the following: Navigate to the tiger.blend file by using either the file browser (dolphin for KDE, Nautilus for GNOME, for Ubuntu whatever they are using) or the command line and try to rename the file into tiger1.blend. If you are able to successfully rename the file then there are no permission problems on the OS level.

Last but not least Blender does not necessarily use all of the Desktop Environment's file selection methods. While KDE's dolphin is capable of browsing paths with blanks (something like //Macbook/Awesome Blender Files/tiger.blend) other file managers might not. Blender seems to process blanks in paths correctly on SMB (samba) and CIFS (common internet file system) shares but I've never tried using Mac OS as a host system. Try to use simple paths without blanks, accents, umlauts, special characters...


Bone parenting without offset using Python? import bpy

ob = bpy.data.objects
child = ob['cube']
parent = ob['armature']
bone = parent.pose.bones['bone']

child.parent = parent
child.parent_type = 'BONE'
child.parent_bone = bone

I wrote the script above to carry out bone parenting with Python.
The parenting setting works correctly, but at the end, the child object's transformation will have an offset.
How can I achieve bone parenting without offset?

Additional questions about batFINGER's answers.
I tested the script. But I still get the offset. Did I make a mistake?
I recorded two GIF to clarify the question.
In the case of the parenting using operator, the cube's transform is maintained, but in the case of parenting using script, the cube's transform changed.
Bone parenting using operator

Bone parenting using script

After creating an armature, change the bone transforms in pose mode.
Operate bone parenting with cube & bone of armature.
The ops method keeps the cube in place, but the script method changes the cube by the bone transform
I want to achieve ops result using python script.

Result by ops (Ctrl+P/Bone after select cube and armature)

Result by script

Set basis and parent inverse to identity.
One of the simplest ways to do this is to set both the basis matrix and parent inverse matrix to identity, to ensure all transforms are those inherited directly.
Getting no feedback re what parenting "without offset" is, have included link to
https://blender.stackexchange.com/a/112856/15543 which has a number of methods to parent, either keeping current global location, (the operator result in question EDIT) or snapping to the transform of the parent as shown here..
The confusion is over the term offset. Code below puts an object at its parents transform with no "offset" from it, no local transforms.
Parenting, while maintaining the object in place, could be considered as setting the offset from child to parent, before parenting.  If turned on relationship lines are a visual rep'n of the parent to child offset.
Code below is same
as 'SNAP_IDENTITY'
import bpy
from mathutils import Matrix

ob = bpy.data.objects
child = ob['Cube']
parent = ob['Armature']
bone = parent.pose.bones['Bone']

child.parent = parent
child.parent_type = 'BONE'
child.parent_bone = bone.name

child.matrix_basis = Matrix()
child.matrix_parent_inverse = Matrix()

Please also notice that the parent bone  setting requires the name of the bone, not the bone itself.


How can I adjust Cycles material displacement amount? The experimental feature set in Blender 2.75 includes an option to allow the displacement socket of the material output node actually displace the mesh instead of acting as bump-mapping.

However I can not figure out how to control the actual displacement amount.  Simply adding a math multiply node does absolutely nothing.

So how can I change the actual displacement amount?

Remember this in an experimental feature it doesn't update atomatically every time. To force update Exit Rendered View to solid view and switch back to Rendered view. Or Render with F12 and you'll see the difference.

With True Displacement x10

With True Displacement x20


Assigning a keyboard shortcut to Accumulate button in Texture Paint Mode I'm trying to assign Shift+A to toggle Accumulate in Texture Paint Mode, I'm not sure how to do it and my attempts so far haven't worked.

Does anyone know how it's done?

Thank you

In the first box type wm.context_toggle.

This will open up another box in the bottom, Context Attributes. Type:

"tool_settings.image_paint.brush.use_accumulate" to set the property you want to toggle.


Best way to complete a cylinder from a segment I have this section of a cylinder and I want to duplicate it around a central point to make a whole cylinder. What is the best way to do this?

Use Extrusion and the Mirror Modifier

Extrusion

If it is just a segment, first Tab into edit mode, rotate to front view (Numpad 1), key E, then Z, and drag the mouse downwards to the desired height for the cylinder.

Mirror Modifier

With the cylinder selected, go to the Object Modifiers tab in the Properties panel and add a Mirror modifier. Set the settings as follows:

This will reflect the segment about the origin (the orange point with the green and red arrows coming from it).


How do I close the gap in a mask inside UV/Image Editor? This is my very first time of using masks and I am testing masks. I want to know how to mask areas of a video. FYI, I am new to mask nodes.
For any assistance, thanks in advance.

You can press Alt+C to Toggle Cyclic, which closes the selected splines. Pressing it again will re-open the mask spline.

This is also found in the Toolshelf (T) in the Mask tab> Mask Tools> Spline section or in the UV/Image Editor header under Mask> Toggle Cyclic.


Moving all files to a new computer, my concern is links I'm moving all files to a new computer, via an external hard drive.
I am certain that broken links will be a concern. What can I do to fix this? Is there a 'Best Practices' kind of way to prevent this problem beforehand?
I have many hundreds of .blend files, and of course, I fear losing them.

I think the key thing here is to always use relative paths in your blend files when linking remote data. That means for linked libraries, textures and any other data external to the file.

Relative paths are guarantied to work if you maintain the folder structure relative to the blender file intact, even if the absolute paths are changed.
That means if you move your files to a different machine or even on your own current machine but maintain their positions relative to each other things should not break.

Whereas absolute paths are never guarantied to work in a different machine, unless you can recreate the exact same base path for everything down to the same drive letter.

The good news is I think Blender already does this by default, so in theory you should not have to do anything, unless your store stuff across different drives letters, crosslink from network data, or specifically set blender to use absolute paths.

You can double check this by opening one of the files in question, going to the Outliner and changing the menu in the header to Blender File this should list all local data stored inside the current Blender file, and bellow it towards the end of the list all loaded external data from other .blends. From there you can check which files are loaded and from where.

If a path looks something like //..\Path\to\my\Library.blend then is relative and all is good. If it looks something like D:\Path\to\my\Library.blend (has a drive letter in it) than it is likely to break in the new computer.

You can easily fix this by going File > External Data > Make all paths relative

Blender has relatively good asset management capabilities, in the new computer you can then check if anything is missing by going to File > External Data > Report missing files

Now make sure that when you move stuff you maintain the same internal folder structure. One good way to organize your projects would be:

Master Folder

Blender Projects Folder

Project 01
Project 02
Project 03
Project ...

Library folder - For reusable assets and library files

Models
Animations
Textures
Materials
...

Independently of where in the file system you place it, if you maintain this internal folder structure intact, and all files reference each other using relative paths within this "garden" all should be fine.


How to randomize audio I am making a third person shooter and I have three different lazer sounds. I want to figure out how to make it so every time I click it plays a different lazer noise.

You can use a python module to choose different sounds to play. The advantage of a module over a script is that a module can have variables that are reset only when the game starts while a script they will be reset each time the script is run.

To treat a text block as a python module you need to end its name with .py and enable the register option in the header. Then you add a python controller and use the text block name without the .py and the function name to run.

Now in the module you need a function to play the sound. getCurrentController will give you the controller running the script and its actuators property is a list of actuators connected to it. We can then use an index to access each item.

import bge

idx = 0

def playsound():
    global idx
    cont = bge.logic.getCurrentController()
    if idx >= len(cont.actuators): idx = 0
    snd_act = cont.actuators[idx]
    cont.activate(snd_act)
    idx += 1

The actuator list can also be treated as a dictionary, so you can choose the actuator by name -

snd_name = 'Sound' + str(idx)
snd_act = cont.actuators[snd_name]


Drivers: How to access "self"? Quick question:

I'm trying to set up a driver which uses the Y-scale of whatever object the driver is on (which means that I don't want to use the Y-scale of a specific object, but rather any object).

I've read that the option "Use Self" is perfect this exact scenario, but I can't figure out how to use the self variable.

Someone suggested I use bpy.data.objects[self.id_data.user.name].scale.y in the python expression but that returns an ERROR: Invalid python expression.

What am I doing wrong? Thanks!

Using self in a driver is not as straight forward as thought, though it is really easy once you know where to put it. In short: In your driver, simply don't declare a variable, but use self in the expression itself to reference to the object. Check this screenshot here:

This driver is hooked up to the scale.y property of an object. The important bit here is to check Use Self as indicated in the upper screenshot, so Blender actually declares what object self is pointing to automatically.

Now you can copy and paste this driver to any other object, it will take the scale.x from there as a driving source.


Do a translate followed by a rotate followed by a translate (This is just a basic example).
I want to translate, then rotate and then translate again (in local).

At the moment I have this:

import bpy
import  mathutils

object = bpy.data.objects["Cube"]

# translate
translation = mathutils.Vector((5.0, 0.0, 0.0))

inv = object.matrix_world.copy()
inv.invert()
vec_rot = translation * inv
object.location = object.location + vec_rot

# rotate
euler = mathutils.Euler((0.0, 0.0, 45.0))
object.rotation_euler.rotate(euler)

# translate again
translation = mathutils.Vector((5.0, 0.0, 0.0))

inv = object.matrix_world.copy()
inv.invert()
vec_rot = translation * inv
object.location = object.location + vec_rot

The problem is that this works as the 2 translates combined followed by the rotate.
What I expect is to have the object first move in the x, then rotate, and then move in it's rotated direction.

How can I do this?

Can also obtain the equivalent of keystrokes gxx5 rzz45 gxx5, (ie local transform on x by 5, rotate on z by 45 degrees, local transform again by 5), by creating transform and rotation matrices, and chaining them together via matrix multiplication in the order wanted.

import bpy
from mathutils import Matrix
from math import radians

# Translation matrices
T0 = T1 = Matrix.Translation((5, 0, 0))

# Rotation matrix
R0 = Matrix.Rotation(radians(45), 4, 'Z')

obj = bpy.context.object

#
M = T0 * R0 * T1

obj.matrix_world = M * obj.matrix_world


Python script unable to import modules I'm trying to follow the scripts from the book The Blender Python API by Chris Conlan, and I've been unable to import modules in Python from Blender (2.81) on osx 10.15.2. What file structure / linking is needed to import modules in Blender 2.8?

The closest question I've seen here is Error: No module named ' .... ', which seems to be close, but the single answer there doesn't work for me. (I don't currently have enough reputation to comment over on that question.)

Specifically, I'm trying to run this example from the code given in the book. The problem is that I don't know how the file ut.py should be handled. Where should it be placed? Does it need to be linked into the blender file somehow?

I've so far been unable to set up a minimal example to get anything to import from another module source file, either using the code from the book or with a minimal example like this. The source code from the book needs minimal refactoring to work with 2.8, but otherwise seems functional.

For me the answer was to put the entire project into a folder with the proper structure and set this as the scripts path in preferences.

This is the folder structure I used, and I was able to run the example scripts from the book:


Making a texture partially see-through I am trying to make a kitchen table/island which looks like the one in the reference image.
I already put light inside the table, but I only want the yellow light to shine through the white parts of the marble texture. The black veines are supposed to block the light.

Is this somehow possible? If yes, can someone help?

Thanks in advance. If you need more screenshots let me know.

Greetings

Kara

One way you could do this is to dynamically create a mask from your marble texture that is used as a mix factor between high translucence and low/zero translucence areas of the material.  So the veins would be low translucence, the whitish parts higher translucence.

This node setup shows the concept in action.  At the bottom on the left is the marble texture I was working with; on the right is a preview of the mask, created using a color ramp.

They say you should always "add" translucence to your other shaders, but honestly I didn't like the way that turned out . . . too bright, hard to see the specularity.  So I used a mix shader instead.  Maybe less physically correct, but I think it looks better.


Is it possible to transport materials between the Internal render and Cycles render for animation? http://blenderartists.org/forum/showthread.php?247271-Cycles-Automatic-Material-Textures-Node

Convert Materials from Cycles to Blender Internal Render

These links claim that it IS possible to transfer Material data between Cycles and Internal, as long as they were created in the Node Editor.

Both have very different options, (one has BDSF shaders and the other has plain old Diffuse and Specular whatnot) but Cycles is much better for designing materials.

Unfortunately, when making animations, Cycles render uses a LOT more resources than Internal render.

Is it possible to design a material in Cycles render (node editor), use the scripts in the links above to move the node data over to Blender Internal, and render animations and scenes with intact Cycles Material data, even though both offer different kinds of nodes for material design?

Materials for blender internal have limited support for nodes, while cycles uses nodes only. The cycles nodes will not work for internal materials nor will internal nodes or material settings work with cycles.

You can create a material that has both nodes in it. There are some nodes that are common to both and can be interlinked with each other.

What this means is you cannot use the same nodes for both render engines, but you can integrate two node setups into one material so that one material can be used for both render engines.

For a simple material that uses an image texture and a diffuse node this will be a simple task. For more complex materials you may find it hard to get the two to match up.

As an example you could look at the materials used in CGCookies Flexrig, the materials there are deliberately created to work with both render engines.

While not large enough to be very clear this is one of the materials in the Flexrig, The red and green frames are cycles nodes while the darker section at the bottom is for BI. The purple section is common values used in both node setups. The cycles nodes appears simpler because they are groups.


Are there any simple way to animate other than by key frames I am a beginner and I know how to make animations with key frames. What are the other ways to make animation?

without keyframes. Can be used Scripted Expression. More depends on what you want to do.
https://docs.blender.org/manual/en/latest/animation/drivers/workflow_examples.html


Generate photorealistic image from STEP files with blender What is the best way to generate photorealistic images of CAD data? We have CAD data of screws, plates, molds etc in different formats. Most of them in STEP.

We have read older posts saying that it is not possible to directly import STEP files to Blender. Does this still hold true? What formats does blender accept when it comes do render photorealistic images?

Simple in 5 steps:

1- Convert the CAD data into a format that can be imported by blender.

2- Switch to cycles render engine.

3- Create realistic materials, assign them to your objects and light the scene in a realistic way.

4- Render.

5- The most important step: Forget about magic buttons that will do all of the previous 4 steps for you, this will require you to do some work and learn how to use the software.


How to accurately recreate a circular design for 3D print? I know there is an easy way to build this but I can not figure out how. Can anyone walk me through the steps to build the following figure easily? I need to basically have a 1/8" circle with 1/8" straight pieces extruding out every 45 degrees.

Blender was never meant for precision work.
One way to get similar results is to use arrays.

Start with proper sized small segments. Add curve + array modifier arround its circle part,

For circumference extrusions it's similar. Use 'object offset' setting in an array modifier.

blend file


Rendering a fake mirror I am trying to work out how to have a fake mirror in my scene.
Character A walks by a mirror on the wall, which should reflect the room and everything in it, except Character A. Instead of Character A, it reflects Character B.
So, basically, I want a simple reflective surface, but:

Character A should not be visible in what the surface reflects. Reflections should be rendered as if Character A is not in the scene
Character B will be in the scene, but only visible in the reflective surface, not in the world itself.

Here, crude graphic to show what I mean :D

Less crude graphic here:

Is this possible with Blender? I'm familiar with all of the most general functionality, but I can't think of anything that would achieve this. Are there data properties I can tweak? Is there a modifier that'll achieve it? Reflection probe trickery?
I intend to use Eevee for the rendering, but if Cycles achieves this better, I can switch.
EDIT: I can of course elect to not using a reflective but a transmissive surface and just model the contents of the mirror behind the surface. So instead of having any reflection at all, I'll just copy and mirror the geometry and do everything manually, but 1) that's a lot of work, 2) not really an answer to the technical question I'm asking.

You can use "Is reflection ray" output from "Light path" node and plug it into the alpha input of the "Principled shader".
This will work for both Eevee and Cycles. For Eevee you need to set "Blend mode" to alpha hashed in the material setting.

For the one that reflects in the mirror but is not visible outside of it:

For the one that is visible only outside of the mirror:

For Eevee, set both objects to alpha hashed in the material settings:


Is there a way to open a .zprj file in Blender? None of the Blender's importation options can take care of the .Zprj file that I have downloaded, as it is never displayed in the file browser.

How do you proceed to open such files ?

Thanks !

.zprj file is a specific file for marvelous designer, as you cant open for example maya .ma because it means to be for maya only. So no, you have to open it in marvelous designer and covert it into other universal format as OBJ or STL


Inconsistent Edge Length in Blender 2.9 Summary of Issue:
The Edge Lengths are inconsistently displayed on an obviously square object.
Issue Detail:
I'm still quite new to Blender.
Iam busy creating door frames using Cube, boolean difference, deleting the inner faces, capping the inner faces, and finally extruding the door frame out.
However, I've noticed some strange behavior. I'm sure this is by design, but it seems to have caused me problems now.
What I initially did was extrude, and type the measurement I wanted (0.004) for the door frame faces.
However, I realized that I actually needed to set it to 0.04 instead.
So instead of extruding again, I selected the faces and used the Move tool to specify my new measurement numerically (0.04) and hit enter.
It seems however that it appends the measurement using some unknown logic which doesn't make sense to me.
The side effect that I'm dealing with now in order to try regain consistency using "Edge Lengths" is that the edges of what is seemingly a square, is actually of different lengths.
I have no idea what is going on, however I can only find help on this for Blender 2.8, and apparently the entire application UI changed within a single minor version number.
Please may somebody help me out here.
This is what I'm talking about:

I can't be sure this is your issue, but overlay 'Edge Lengths' are displayed in Object space: that is, before any Object-level transform the object is carrying.
This plane has been scaled by 2 in Edit mode, doubling its vertex X-locations in Object space. The rectangle has then been scaled by 0.5 in X, in Object mode, restoring it to a square in World Space, but only by virtue of the transform the object is carrying.

If you CtrlA 'Apply' the scale-transform of the object, that will reset the object's X-scale to 1, and bake the object's scale into the Object-space locations of its vertices.
(The shipped add-on MeasureIt displays dimensions in World space.)


Why are all my HDRIs displaying distorted? Here's an image of the distortion.  And here are my shader settings
I'm just a beginner in Blender, and at first my HDRIs (from HDRI Haven) were working fine, but now they all display distorted as shown. Can you tell me what I'm doing wrong? Thanks for any advice!

Delete the texture coordinates node. Delete the vector mapping node. Delete the image texture node.

Add an Environment Texture Node, use the image in it and set it to Equirectangular.


How do I stop curves from changing shape when joining them? I have made hair for my avatar using this tutorial: https://www.youtube.com/watch?v=Nn7mISvVzJk

I followed it to make hair by using a bezier curve and shaped and tapered it with a bezier circle. I used multiple curves and circles, and as a result ended up with like 50 strands of hair. I need to join them together to have one manageable piece, but when I try to join locks from different circles, one of the locks will distort.

Can anyone please help stop this from happening??? ASAP!

Also, I tried to join a lock to the head instead, but it says no mesh data to join. Is this because I have mirror or subdivide modifier on? If I select the skin and then the lock of hair, ctlJ won't do anything at all.

Okay, so I needed to turn the curves to mesh using alt c and then join them. At least I ended up figuring it out!


It is possible to use Antialiasing in Multitexture mode? It is possible? or it is just a GLSL feature?

Make sure Blender's interface is set to "Blender Game" (usualy in the top of the blender window):

Then go to the "Render" settings in the properties panel. Under "Standalone Player" you can set the antialiasing samples:

If you also want to enable Antialiasing in the viewport, which also affects the embedded player, you have to set it in the user preferences. Press [Ctrl+Alt+U] to open the User Preferences window. Then go to System and set Multisample to your desired AA factor.
You may have to restart blender for this setting to take effect.


Automatic select vertices by given coordinates I have a mesh with some thousand vertices and want to select a few specific. An external program choses the vertices i have to select. They are too many to do it manualy. My first idea was to take a look in the obj-file, look for my coordinates and use their line to select them in Blender. But thats not possible, because the IDs of the vertices in Blender are not given in the same order as the coordinates are written in the obj-file.

My new idea is to extract the required coordinates from the obj-file and look for them in Blender. I've already extracted the required coordinates in a txt-file.

Is there a Blender console command or script to select a vertex by given coordinates? I know that i can select a vertex by it's ID.

If the indices no longer correspond, you can:

use a brute-force proximity check
use spatial search structure (K-dimensional-Tree).

  Template for getting a bmesh in Object or Edit mode can be found in:
  TextEditor > Templates > Python > Simple Bmesh (EditMode)

Brute Force

For each coordinate listed in coords_to_find it will select the first vertex which has a similar 3d location. Due to numeric imprecision of 32bit floats we might use an Epsilon as a fuzzyness factor, and say "Any vertex coordinate found within linear distance Epsilon of a given coordinate is the one we want", then skip on to the remaining verts and coords.

Below is a slight modification of the Bmesh template, it assumes we have a mesh object in edit-mode, i happened to use a Suzanne model.

import bpy
import bmesh
from mathutils import Vector

coords_to_find = [
    (0.3203125, -0.734375, 0.7578125),
    (0.0, -0.2890625, 0.8984375),
    (0.453125, -0.234375, 0.8515625),
    (-0.6328125, -0.28125, 0.453125),
    (-0.796875, -0.125, 0.5625),
]

# Get the active mesh
obj = bpy.context.edit_object
me = obj.data
bm = bmesh.from_edit_mesh(me)

Epsilon = 0.00001

"""
Here we iterate over the lists of verts and coords. We remove
the coordinate from the 'coords_to_find' once it's found. this
decreases the number of comparisons on the remaining vertices.
-- it might also make sense to _break_ when 'coords_to_find' is empty.
"""

for v in bm.verts:
    for idx, coord in enumerate(coords_to_find):
        if (v.co-Vector(coord)).length < Epsilon:
            v.select = True
            print(v.co)
            coords_to_find.pop(idx)
            break

# Show the updates in the viewport
# and recalculate n-gon tessellation.
bmesh.update_edit_mesh(me, True)

KDTree

An alternative, which might be faster (especially noticable on larger objects) uses the built in KDTree module. There are 3 search functions find, find_n and find_range.

import bpy
import bmesh
from mathutils import Vector, kdtree

coords_to_find = [
    (0.3203125, -0.734375, 0.7578125),
    (0.0, -0.2890625, 0.8984375),
    (0.453125, -0.234375, 0.8515625),
    (-0.6328125, -0.28125, 0.453125),
    (-0.796875, -0.125, 0.5625)
]

# Get the active mesh
obj = bpy.context.edit_object
me = obj.data
bm = bmesh.from_edit_mesh(me)

size = len(bm.verts)
kd = kdtree.KDTree(size)

for i, vtx in enumerate(bm.verts):
    kd.insert(vtx.co, i)
kd.balance()

for idx, vtx in enumerate(coords_to_find):
    co, index, dist = kd.find(vtx)  # dist is the distance
    print(idx, vtx, index, co)
    bm.verts[index].select = True

# Show the updates in the viewport
# and recalculate n-gon tessellation.
bmesh.update_edit_mesh(me, True)


Modelling a computer monitor - need some topology advice on using edge loops for sharpening I'm modelling a computer monitor (as a learning exercise after completing Blender Guru's "Donut" and "Anvil" tutorials) and need some advice on how to use edge loops the right way for sharpening some details. Please let me explain my problem with a few screenshots, see below.

The last screenshot shows the problem, the three edge loops over the corner surface causes problem when applying subsurface modifier.

I really like to learn the best way of working with topology, maybe someone can guide me in the right direction on how to model my example in a better way? My blend file is attached at the end.

Overview of model (using Mirror modifier):

Detail on my edge loops  for sharpening the corners:

Artifact visible using Matcap shading:

Blend file:

Here's one possible solution. Model with quads for your front faces (Don't have an edge on the corner).


Does Blender API have any evaluation function for Bezier curves? I'm trying to export Blender Bezier Paths to Unity, so that Unity objects can follow along those paths.

The 2 ways to do this that I came up with so far are:

Blender script creates an empty for every control point in the Blender path, then those get imported into Unity as empty game objects (aka transforms) and from within Unity I can calculate B(t) based on the control points.
Blender script takes a "resolution" parameter, which it uses to
evaluate the path and instead create an empty along the path for
each sample. Then those get imported into Unity as empties and from
within Unity I just have the objects follow this checkpoints along
the path.

For approach 2, I'd need to evaluate the spline inside blender. And I was hoping that bpy.types.Curve would have an eval(t) or similar method but I haven't found anything in the API so far.

So my question is, is there anything in the Blender API for evaluating or do I need to write the evaluation code myself?

Ok I found it: mathutils.geometry.interpolate_bezier().


wireframe while everything else is solid hey I'm new to the site but I am making a game in blender. there is this problem where everything is solid but this one object is stuck in wireframe while the rest is solid. I have checked the maximum draw type it is set to textured. please help.

Check in edit mode if your object actually has faces. Otherwise go to the the material tab and see if you have invisible (next to backfacing) checked, as it makes the objects look like wireframe. I added some images to show. Hope I was helpful.


Scale deformation when rotating imported FBX I've been working on this gun model and all was going well until I tried importing it into another blender save, I then realized that the imported FBX's parts deform when I rotate them, this does not happen in the .blend save of the model however. I have tried un-parenting all the children and then reattaching them and exporting it and re-importing it again but still whenever I rotate a child of the main weapon it deforms and stretches. No idea what's causing it, it's especially strange because it doesn't occur in the .blend save of the model but does if I import it into a blender save. Here are some screen shots for example.

Base Weapon:

Rotated Children:

Rotated Children on same model, but reimported (Above):

Thanks, any help or suggestions would be appreciated, I'm stumped. <3

Make sure you apply all rotation and scale to the children before parenting them, having weird scaling can produce those results.

You can do this by selecting the child in object mode and pressing Ctrl+A and selecting "Rotation and Scale".


blender with openGL 1.3 or lower is there a way to bypass this openGL support, i just need to run this program on low spec computer in purpose.

or maybe there's another suggestion about what program that i can use with OprnGL 1.3

best regards~

Blender 2.76 does appear to have support for opengl 1, but i thibk that is the CPU doing most of the rendering, and alot of the lighting is miscalculated when loading projects from newer versions of blender(not sure about older ones)


How do I alter keyframes for a new framerate? I created a new scene for a new animation. I didn't know this at the time, but a new scene is a new world, so settings will be back to default. I made all my weapons, models, HUD elements, and others with the default settings. Whats the problem with this? I have 60 fps for my animation framerate, but the new scene has it on 24.

Yes, I should simply increase it to 60 to match everything else, but all my animations will run faster than 2x regular/intended speed. I could set it to 60, and do whats on my mind: delete and rework all of the tons of animations I have created.  I obviously am looking to an alternative, and I am thinking that, hopefully, in some way, I can take an animation and maybe move the frames or have all the frames moved by a percentage (example: original frames = 10, moved by 150% makes total 15 frames)?

In object mode, select all the objects for which the animation rate needs to be changed from 24 to 60 fps.

In the graph editor, place the 2D cursor at frame zero, and set the pivot center to 2D Cursor

Hit A once or twice to select all of your keyframes. (You may want to hit CtrlH to hide the curve handles if it looks too busy)

Hit S, then X to scale horizontally, then type 2.5, then Enter

This scales your 24 frames-per-second animations out a multiple of 2.5 to 60 frames-per-second.


Cycles - camera motion blur only on certain objects? Is it possible to disable camera motion blur for certain objects?

The motion blur checkbox in the object properties only seems to affect object motion and deformation? But if the camera moves the object still is blurry.

One possiple way to solve this problem is by assigning a object or material index to the objects, that should not be blured. than you enable the Vector pass in your render layer. In the compositor you can than remove your objects from the image (with the id-mask) and replace them with black (do the same with the vector by just handling the vector like an image), apply the vector blur and add your objects again.


How to add driver to emissive color in Cycles? I want to add a simple one-line driver to control the emissive color of a material in Cycles.  I had assumed I either hover over the color and press 'D' or right-click and select 'Add Driver' from the context menu.

Neither of these options worked, so I searched around and found some forum posts that suggested finding the emissive color datablock in the outliner, but that did not work either.

Lastly, I tried the same shortcuts in the Node view of my Cycles material network.  That also didn't work.

In all three cases I tried both right clicking the color AND right clicking the RGB values inside the color inspector.

I feel like I must be overlooking something extremely simple here, as driving a color property seems like a common task -- a natural next steap after animating a color property with keyframes.

I am an idiot -- if the value is already keyframed you are not able to add a driver to it.  Once I deleted all the existing keyframes I was able to add a driver.