text:
Point features to 3D models with same scale of object
Object Link Data Approach: as suggested in this given link: Is there any way to replace an object?
I have uploaded my screen shot of my workspace.

IMPORTED SHAPEFILE- using BlenderGIS Addon:- yellow encircled objects are those POINTS of pole locations.
IMPORTED COLLADA MODEL- Red encircled is the 3D collada model. I need to replace those points with pole.

I hope it is clear now. Pardon my language. I am ready to share the data if required.

Scales of both objects are different. even sources are different. There are so many such point features in this SHAPEFILE data (110 points needed to be replaced with POLE).
After doing that, a giant object is displayed as result.

Thanks for cooperating.

Sorry, it's not quite clear to me what you exactly are you talking about. Could you provide some context? The words "point" and "features" make me think about camera tracking, but you tagged modeling. What are the "transmission poles"?

I imported shapefile containing locations of transmission poles. then I imported one  transmission pole 3D collada model with required height.      I need to replace that points with the 3D collada model. itried it with "make link with object data", but the size of 3D models are too big. I hope things are clear now.  So I want to replace points with 3D object of required size(here 5meter).

So you imported two models and their scales don't match? Should they? Do they come form the same source? Objects can be scaled in Blender, what's exactly not working? How are you planning to "replace points with 3D model"? Using a particle system? Dupliverts? Manually? It's hard to help you without further information, please edit your question adding all the info about your situation.

Thank you, now it's clear. Do the POINTS belong to different objects or are they vertices of the same object? The Link Data appoach works ony if they are all different objects and their origin is properly placed. Did you try the solutions proposed here: https://blender.stackexchange.com/questions/44353/how-to-add-multiple-meshes-on-the-locations-of-the-vertices-of-for-example-a-s ?

Those all POINTS are of same size. Each point denotes the location of a transmission pole. (i.e., each POINT is different object.)       https://blender.stackexchange.com/questions/44353/how-to-add-multiple-meshes-on-the-locations-of-the-vertices-of-for-example-a-s  - This is not am looking for. I would like to create a 3D model of City with Power sSupply system included in the model- like poles, supply lines. So I ahve locations of poles as POINTS. I want o replace those poles as POINTS.

Could you upload your blendfile or a portion of it to http://blend-exchange.giantcowfilms.com/?

I tried to drag the blend file there. But it id not working.. Anyother option to sent the file?

I would not recommend any site other than that. What did you mean by "it is not working"? The upload fails? You can't copy/paste the link? Did you check the help page: http://blend-exchange.giantcowfilms.com/help/?

Even if am drag and drop the blend file, that file is not being added/ copied in the specified space.

Isn't any error/waring appearing? Did you paste the question link in the field?

there is no warnings/errors. I a =m not able to upload. :-( I am following the same way as mentioned in HELP.

You can try to contact the runner of the site (mail address can be found at the bottom of the help page) to try to understand what the issue with the uploading is.

Shall i mail you that in personal if you dont mind. vishnuedakkat93@gmail.com is my mail id. Pls help

The purpose of using that site is to provide a permanent storage of the file linked to the question that anyone can inspect to help in finding the solution. It's more important you share it with everyone rather than me only: I'm asking questions beacuse the problem is not clear, not because I think I may have a solution. Upload it in another site of this kind if that doesn't work (google drive, dropbox,...) and share the link here. It would be also helpful if you answer all the questions in the comments (e.g. Do the POINTS belong to different objects or are they vertices of the same object?)

I hope I replied to all the questions. Pardon my language as am poor in communication. Sorry for the trouble. I was not able to understand why that  site was having that issue. I tried in my lap, still faced same issue. I thought of sharing data as that option of uploading was unavailable with me/ my system. i am copying te link here: https://drive.google.com/open?id=1DyBcvPFT8j9AgQpxW4rr6DKvi8SR803D thanks

Object Link Data substitute the whole mesh, not the vertices
The method you proposed works with the substituction of the Mesh Data, but it requires to have multiple objects to work with (one object for each pole).
Currently, all the points are all binded inside the same mesh data, so they are simple vertices of the same mesh. Points are currently threated as a whole. Look in the outliner that only an object is selected:

You'll need at least to split each vertex into an individual object and set the origin of each new object on its geometry.
Enter edit mode, select all, press P and choose "By loose parts". Notice that now the outliner has many object. One for each disconnected vertex.

Enter object mode without losing the selection and set the origin of all the objects to the geometry.
Now you are ready to Link another Object Data to those object. Before running the operator make sure to apply the scale of your pole object.

Note: You'll probably have many advantages in adopting another approach to the task, like for example using the instancing of dupliverts or a particle system which both offer a greater level of interactivity (object is instanced on the fly, you control only the vertices) and avoid splitting the objects in many other objects.

Thank you so much.... Really happy with your  response. Thanks..:-)


text:
How do you render background image through transparent object?
I tried rendering an object that has a mixed glass and diffuse shader and also a background image but after adding a holdout shader in image 2 to make the object transparent to see the background image the glass shader becomes darker.
Image 1:
Image 2 :
Without transparent shader:
Nodes for background image:
With transparent shader :

That's because the way you have it set up, it's going to be transparent on the edges and solid in the middle. Switch the top and bottom slots, and it should fix it!
EDIT: The Holdout shader also only uses what you have set for your world background. It's going to show up as a basically a hole to show the background through, with no consideration for any other object or faces behind it. If you simply want transparency, use the Transparent node instead of Holdout.
(It's doing what you you want, this is just how it looks in preview; see how it looks in render, then switch the top and bottom slots to see if it looks better, as well as also hookup up your mix factor back into your original mix; it can hook up to more things at once!)
EDIT 10/19: By switch the slots, I mean the sections that say 'shader'. When you use a mix factor, it's telling Blender to make all the white one of the shaders and all the black the other shader. Any mix is a combination of the two. Fresnel as a mix mask looks black where it's facing the camera, and white where it's angled away, and a fairly short falloff between the two. This means if it looks funny, you might simply have it hooked up opposite from the way you want, where it's hooked into the little green dots that say 'shader'.
To further this note, you don't have the same mix factor in your addition with the holdout. You just moved it to the second mix. For better results, plug the Fresnel Fac into the the gray dot that says Fac on both mix shaders.

Thank you for responding Lee. I'm not sure what you mean by switch the top and bottom slots. Using the transparent shader doesnt seem to solve the problem. I've updated the question so you can see what happens when I add the transparent shader.

Updated; did that help? I'll reword as much as you need me to. This is a pretty complicated subject, but once you get the hang of it, it'll seem much easier.

Basically all I want is for the object to be glass/plastic like and let the background image be visible through it. I know this is a simple fix but I just cant seem to get it. I followed what you said but it doesn't seem to work. Here's a link to the file if you ever have time : http://pasteall.org/blend/index.php?id=50526

Alright, I don't know what's going on with that file, but I can't seem to even select your lightbulb. However, if all you want is a nice glass material without fussing about all the rest, try using a principled shader, and playing with the transmission slider (that's transparency). It calculates refraction and fresnel automatically!

source: Stack Exchange

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

sort: votes


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SCULPTING: Is it possible to keep base mesh vertices in place while subdividing?
What I'm looking for: a way to stop the starting mesh from melting into an unidentifiable blob of vertices when applying a MultiResolution modifier.
Background: I'm currently following a Game Design course, which involves Maya, ZBrush and Substance Painter.
Soon or later I'll run out of trial/student licenses, which means I'll have to either buy these softwares or find cheap/free alternatives.
Now, allegedly, Blender can easily replace Maya for nearly everything, and Substance Painter is actually already quite cheap (only 20$ a month for the indie license).
ZBrush, on the other hand, is a bitter pill to swallow, because it costs a lot!
Fortunately, Blender seems to integrate a sculpting feature that might even be good enough to efficiently replace ZBrush.
My concern, though, is with the subdivision method/results: I've just tried to subdiv a cylinder by using MultiResolution, and now it looks exactly like a hot-air balloon.
The lump-ish result was expected, but I'm a bit upset because I can't seem to find a way to revert this result to something that even just resembles the original shape.
In ZBrush, by using "Morph Targets", one can easily revert the most deformed/shrinked model to its original volume, while still getting that nice, smooth look subdivisions usually bring. A final touch of Crease here and there where needed and you basically have a smoother version of your original model, but without any loss in volume/shapes.
The routine is: store target, subdiv, down to previous level, restore target, move onto higher level, store target, subdiv, etc etc....
So my question is: is there any way to emulate the same process in Blender? Is there a way to achieve the same result?
[UPDATE - 2018.04.13]

As you can see, there's nearly no difference between Maya's, Blender's and ZBrush's smoothing, they're all a basic application of the Catmull-Clark method.
BUT! If you store the vertices' position in a "morph target" before creating a new subdivision level, and then re-apply it on the same source-level, the new level's vertices' position is recalculated on that scaffolding, hence restoring the previous volumes and shapes.

Of course there is. Just tools will be different, but there's Crease in Blender (Edit mode > Shift+E), there is sharp edges mark (Ctrl+E in Edit mode), there are always supporting loopcuts (Ctrl+R > drag the cut towards edge you create less smoothened corner). See also https://blender.stackexchange.com/questions/6425/keep-sharp-edges-when-using-subdivision-surface

@MrZak That is not what I asked. My question is mainly about maintaining the original shape/volume of the starting model. Crease and loopcuts can maintain edges, but won't prevent Catmull-Clark from shaving off 1/3 of the volume of your mesh.
I know what I'm talking about, I've stopped hitting "3" in Maya just because of that reason: there's no actual correspondence.
Forget about stupid cylinders, imagine the cheekbones of a skull....crease and edgeloops mean nothing!!

In addition to what Mr Zak mentioned, you could try:

Both Subdivision Surface and Multiresolution have a Simple option,
when you turn it on, each subdiv will add vertices between already
existing ones without averaging the general shape.
Secondly you could make a
copy of a basemesh, then add ShrinkWrap modifier on the mesh you will
subdivide and pick the copy as a target. This way you will keep the
mesh shape the way you want it. Both copy and subdivided mesh must be in the same location.

Nope. The "Simple" option doesn't apply any smoothing at all, and the "ShrinkWrap" function gives the same result but in a more complicated, less predictable way.
Gonna update the thread with some more details, maybe I'll manage to explain myself better.

Simple does not smooth at all, thought that's what you were aiming for - increase meshes density without adding smooth (which is the cause of the blobbing).
Shrinkwrap might seem complicated but it actually snaps all the vertices from mesh it is on to closest points on surface on target mesh, and this is what I would ask you to experiment with if you want to have mesh as similar to original as possible. However it will only change shape, not amount of vertices.

That's what I want and that's not what I want. I have already experimented with ShrinkWrap, but if you project vertices onto an edgy low-poly model, you obviously get just an edgy high-poly model.
I've updated the thread, maybe now it's clearer.

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


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Shortcut to change Type of Sequencer View
There's three buttons in the VSE header that let you turn on/off the preview and sequencer:

Do these have a keyboard shortcut?  And if no, is it possible to set one up?

It's possible, but you'll have to write your own operator. (Related). I've written most of one, but I can't seem to figure out how to add arguments to a custom operator..? I may have to ask that as a question ;)

@gandalf3 give the operator a property, then specify the property value when putting the operator in a layout, or when adding to shortcuts the property will be visible to set.

@sambler Thanks! I think added a property (I might have done something wrong), but was trying to call it like an argument.. It seems my operator isn't needed anymore anyway..

@gandalf3, if it's already done, you could still post it, especially since there's an unresolved bug which causes problems when you go into Preview mode (instead of skipping straight to Both mode).

@Garrett It's partially working, however there is some strangeness with global shortcuts only working when in sequencer only view (despite being assigned in sequencer "global").. I also failed to get an Enum property working, so I'm using a String as a workaround..

The default shortcut to change view type in the sequencer is CtrlTab
The one shortcut cycles through each display option.

As pointed out by Sambler, CtrlTab already cycles through the three sequencer views.
It's also possible to set up a shortcut to toggle between two of them:

Go to File > User Settings > Input, and expand Sequencer, then expand Sequencer (Global)
Scroll down, hit Add New and expand the new shortcut
In the textbox that has "none" in it, type wm.context_toggle_enum
Set the keyboard shortcut to what you want
In the Context Attributions box, type space_data.view_type
In the two Value boxes, type SEQUENCER and SEQUENCER_PREVIEW

You could have figured out the last two steps by changing the sequencer view and looking at the output in the Info window.

This is the solution I'll be using until the developers fix this bug which causes problems after opening the PREVIEW view.

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


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Can't change opacity of scene strip in Video Sequence Editor
In the VSE, I have a scene strip, but I cannot change the opacity.  It just snaps back to the last value it was keyframed at as soon as I alter it.
(Blender 2.69)

This is already a known issue that is on the To Do list for the VSE.  I'm posting this Q&A because it took me a long time to come across the solution.
As explained in the above bug report, in order to keyframe a scene clip, you must turn off the preview.

It's so tedious those little things. VSE is probably the most unfinished part of blender.


text:
Clipboard erased when quitting Blender on Ubuntu
If you highlight text in Blender and press CTLC to copy it, then quit Blender, you can no longer paste that text.
Why not?

I posted a bug report on this, but apparently it's not Blender's fault.
As Sergey explained in the bug report, Blender only instructs the clipboard manager to save the text, but in Ubuntu, this is a bug that affects many programs.  You can read more about why it happens here.
Going to the Ubuntu Software Center and installing the application Parcellite, which is an alternative clipboard manager has fixed the problem for me.
EDIT: I also had some problems with Parcellite and Blender working together.  You could try a different clipboard manager.

This is a long-standing design flaw in the X clipboard. The master Ubuntu bug: https://bugs.launchpad.net/ubuntu/+bug/11334


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Object selection box in addon
In my addon panel, how can I have an object selection box?  And what data type would I use to store the the selected object?
It should look like this:

Related https://blender.stackexchange.com/questions/30487/object-selection-box-with-eyedropper

Building off of the answer by @CoDEmanX, here's a simple example:
import bpy

class OBJECT_PT_HelloWorldPanel(bpy.types.Panel):
    """Creates a Panel in the Object properties window"""
    bl_label = "Hello World Panel"
    bl_idname = "OBJECT_PT_hello"
    bl_space_type = 'PROPERTIES'
    bl_region_type = 'WINDOW'
    bl_context = "object"

    def draw(self, context):
        layout = self.layout
        scene = context.scene
        layout.prop_search(scene, "theChosenObject", scene, "objects")

def register():
    bpy.utils.register_module(__name__)
    bpy.types.Scene.theChosenObject = bpy.props.StringProperty()

def unregister():
    bpy.utils.unregister_module(__name__)
    del bpy.types.Object.theChosenObject

if __name__ == "__main__":
    register()

which gives:

How script works
The prop_search command lets the user choose one item from a bpy "collection" (in this case, the collection context.scene.objects) and saves the name of that item into a string (the string context.scene.theChosenObject).
If you need to use the object in a different part of script.  Use
scene = context.scene
obj = scene.objects[scene.theChosenObject]

By the way, if you had wanted a "Materials Selection Box", you could have used
layout.prop_search(scene, "theChosenMaterial", bpy.data, "materials")

and similarly for textures, meshes, or any other bpy collection.
Limitations
We are only saving the name of the object (for example, scene.theChosenObject could be 'Cube').  If the user changes the name of the object, scene.theChosenObject will not change and you will not be able to use it to reference the object anymore.
See here for more on this problem.

Shouldn't the second code box say scene.object[scene.theChosenObject] rather than scene.object(scene.theChosenObject)?

I think unregister should del property from the Scene, not from the Object? i.e del bpy.types.Scene.theChosenObject

Use prop_search(), a StringProperty and a CollectionProperty.
import bpy

enum_items = (
    ('FOO', 'Foo', ''),
    ('BAR', 'Bar', '')
)

class HelloWorldPanel(bpy.types.Panel):
    """Creates a Panel in the Object properties window"""
    bl_label = "Hello World Panel"
    bl_idname = "OBJECT_PT_hello"
    bl_space_type = 'PROPERTIES'
    bl_region_type = 'WINDOW'
    bl_context = "object"

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

        obj = context.object

        col = layout.column()
        col.prop_search(context.scene, "coll_string", context.scene, "coll", icon='OBJECT_DATA')

def populate_coll(scene):
    bpy.app.handlers.scene_update_pre.remove(populate_coll)
    scene.coll.clear()
    for identifier, name, description in enum_items:
        scene.coll.add().name = name

def register():
    bpy.utils.register_module(__name__)

    bpy.types.Scene.coll = bpy.props.CollectionProperty(
        type=bpy.types.PropertyGroup
    )

    bpy.types.Scene.coll_string = bpy.props.StringProperty()

    # Hack for testing
    bpy.app.handlers.scene_update_pre.append(populate_coll)

def unregister():
    bpy.utils.unregister_module(__name__)
    del bpy.types.Scene.coll
    del bpy.types.Scene.coll_string

if __name__ == "__main__":
    register()

For limitations please read:
Is it possible to use bpy.props.PointerProperty to store a pointer to an object?

Here is an updated answer built on previously accepted answer.
Since 2.79, you can use bpy.props.PointerProperty to store references to blender data blocks.
You can then use prop instead of prop_search for selection box. prop_search is still useful if you want to select from a specific collection.
This solves the problem of modifying the object ( for example if you rename the object, the property will be updated). Also, deleting the object will not delete its data as, long as it is referenced somewhere. After all its references are removed, it gets deleted on file reload.
import bpy

class OBJECT_PT_HelloWorldPanel(bpy.types.Panel):
    """Creates a Panel in the Object properties window"""
    bl_label = "Hello World Panel"
    bl_idname = "OBJECT_PT_hello"
    bl_space_type = 'PROPERTIES'
    bl_region_type = 'WINDOW'
    bl_context = "object"

    def draw(self, context):
        layout = self.layout
        layout.prop(context.scene, "theChosenObject")

def register():
    bpy.utils.register_module(__name__)
    bpy.types.Scene.theChosenObject = PointerProperty(type=bpy.types.Object)

def unregister():
    bpy.utils.unregister_module(__name__)
    del bpy.types.Object.theChosenObject

if __name__ == "__main__":
    register()

Can poll to narrow down selection see https://blender.stackexchange.com/a/101303/15543

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


text:
Bake displacement to alpha channel washing out colour channels
I'm trying to put a displacement map into the alpha channel of a normal map.  As per answer to question "Bake displacement to alpha channel" I am trying to use the Node editor for this purpose.  The result washes out the colour.  I have my problem demonstrated in a test case as follows.  I have two (RGB only) images: PaleBlue is coloured (0.5, 0.5, 1.0); DarkGrey is coloured (0.25, 0.25, 0.25).  I am trying to combine the colour channels of PaleBlue with the red from DarkGrey as alpha. The screen shot shows my results.  On the left are the two input images (RGB only).  In the middle is my node structure - a bit more complex than needed, but I think this explicitly shows what I want done.  On the right are two views of the output - actually the Viewer Node, but the Render Result is the same.  The top view is the colour component, the bottom the alpha channel.  Note that the colour is white - not pale blue and that the alpha channel is black.
First screen shot removed to be within link limit.
Question Update:  I've made the recommended change.  It improves my result, but still have somewhat washed out colour and 'brightened' alpha.

Question Update 2:  Here are views of a parallax mapping texture (obtained from other sources) and what it should look like in the image viewer.

Before trying to answer your question, I'd like to ask why are you adding an alpha channel to a normal map? That doesn't make any sense. Normal maps are supposed to be used as non-colour data in shaders or compositing, they don't have transparency.

Hi Gez,  Thanks for taking an interest, but I was happy with the replies I received back in March.  The reason for the alpha channel was that I was adding a height map to the normal information for use in a parallax mapping algorithm.  - Cheers / Bill

Ah, so it's not used as transparency, but as an added channel to be used as a height map. Gotcha.
Well, in that case, the problem you're having is alpha association. You need your file to be stored in a format that manages unassociated alpha, and you have to make sure that the program (Blender or whatever you use to deal with these maps) doesn't EVER multiply your texture by alpha channel.
The only way I know to do this is to connect your pure RGB to the the "image" socket in the compositor and connect your alpha to the Alpha socket and saving to, say PNG which stores unassociated alpha.

I.e.: don't assign the alpha channel to the RGB image, just plug them separated to each socket of the output.

Connect your image node to your Alpha inputs

If Im Looking strictly at the color values and ignoring the alpha, then the value results will be as follows:

And If you are looking to come at this from the polar opposite, then here is the result:

Thanks for the reply Rick.  It certainly improves my result.  However the colour channel and the alpha channel are still not the colours expected.  Note that the blue is still somewhat washed out and the alpha channel has a value of 0.5 instead of 0.25.  Sorry, haven't been able to add a screen shot to this reply.

Thanks again for the reply.  I've added a new screen shot to the original question. @Rick Riggs

I think that this should be the expected result, as your Red value is already starting @ 0.5 (0.25 = 0.5 * the Original Red information on the PaleBlue image). Simplifying this down to the red channel only you started with a red value of 0.5, and the delta between this red channel and the one on the Grey image (0.25) = you subtracted 50% from the original, by making half of this red channel transparent. @Bill

I'll include a little context to this as part of my answer. @Bill

Hmm.  Maybe I am doing completely the wrong thing then.  My goal is to make a texture for parallax mapping, with normals in the colour channel and a height map in the alpha channel.  I just require the node system to assemble the unmodified values from my two sources.  I don't understand why any scaling to the colour values should occur with the node rig.  If red was modified by alpha, it would get darker, not lighter.  I'll add an image to my post showing a parallax mapping texture obtainef from another source, displayed with view = combined/colour only/alpha only.  @Rick Riggs

You can import image as a plane, sub-divide it a little and use a displacement modifier, then use the B&W as the texture to displace, then use blender to bake the "Normal Map", which should produce the end result that you are looking for. Other than that, I'm not sure how to accomplish this through the Compositor. @Bill

Yes, the Baking capabilities are great for making Normal image and Displacement images.  The problem has just been assembling them into a single image with displacement in the alpha channel.  I have used more complex layered texture construction methods in the past to make the combined image.  It is a bit fiddly and requires manually scaling everything.  The baking method is easier (much) to use.  I got the idea from a tutorial: http://lostres.wikidot.com/parallax-map-with-blender.  The tutorial does end abruptly and with what I now recognise as odd colouring in its output ... @Rick Riggs

I've been doing some reading (esp https://wiki.blender.org/index.php/User:Bartekskorupa/Display_Issues) and it appears that alpha display is quite complex with an option to turn on or off pre-multiply-alpha.  Experiments have produced a variety of interesting results (but not the one I want).  I think that I must give up at this point, save normal and displacement files, and write a program to combine them outside Blender.  Many thanks for your patience and assistance. @Rick Riggs

It seems that you would be able to use cycles for this operation though. there you should be able to map out the Calculated Normals, and Map the Desired Color Sheme to a displaced mesh using your displacement map. Let me know if this sounds like something that you would like to know more about, and I will append my answer to address the steps involved to accomplish it, I would just ask that you provide the RGB values for each direction of the Normals. @Bill

I'm answering this myself - but thanks to @RickRiggs who gave me lots of advice and ideas on the way.  There were many issues.  It turned out that part of the issue was alpha pre-multiply (aaarrrggghhh - whoever thought of that idea).  I found it very hard to tell when and if it might apply, but putting in an Alpha Convert node with setting "Straight to Premultiply" definitely prevented it, despite the fact that its wording kind of suggests the opposite - bit of a theme begins here (maybe its because I am in the Southern Hemisphere and see things the other way up) - possibly the node marks the image as having been premultiplied and therefore prevents it?  At that stage putting a constant value in as alpha to the CombineRGBA node worked - the value ended up in the alpha channel of the finished image without changing any of the colours.  Unfortunately connecting the Red channel from the Displacement Map image caused colour damage to recur.  I tracked this down (I think) to the fact that the Displacement map was in sRGB.  When I changed it to 'Non Color' and regenerated, everything worked. Maybe I should have thought of it, but it was fortunate that I didn't.  It is important that the Normal Map is in sRGB space, else pre-multiply occurs again.  The only other unexpected feature was that baking the displacement map gave displacements in the range 0 to 0.5, hence the Math node to double displacement values.  The only other thing that gave me persistent problems was the fact that it the displacement map 'Normalizes' rather more when the Normalize switch is turned off - maybe that's a Southern Hemisphere view again.  Finally Rick - connecting the alpha input to the Viewer and Composite nodes causes trouble now that I have the Alpha Convert in place, so I removed those connections.

Wish I had spotted this earlier. Short answer: associated alpha is the one true alpha (premultiplied) but you always must unassociate (unpremult) when doing colour operations, then re-associate. Search for more answer from @gez for more information. Also, file formats matter; use EXR.

What you do looks fine but you have to be careful with math node. If you don't check "clamp", you'll get alpha values greater than 1. It can be a problem or not, but you have to know it.
If you want fine control, you can use a color ramp to find the position where you want full white and full black (or anything else).
You can use the node "set alpha" to make things easier.

Thanks for the comments - I wasn't aware of the colour ramp option and will probably use it in other situations.  In this case a linear ramp is needed.  I prefer not to use clamp, because I need the values to be in the range 0 to 1 naturally.  If they are not then I have something else wrong and it's probably best to know about it.  On a positive note, I found out more about how to use depth baking and now have the depth scaled correctly.


text:
How to constrain scaling and connection points
I have a blend file with a window frame with sashes and glass.  I want to group this and instance it, then scale the instances to use in many places with different size window openings.
I designed the parts so that the thickness of the wood can scale lengthwise, but not in width. This means that for vertical pieces, Z would scale, but nothing else.  For horizontal, X but nothing else.  For the glass panes, X and Z can scale.
The trouble is that when scaled up the vertical pieces will scale in Z proportionally.  But since the horizontal pieces are locked in Z, a gap forms where they sit on top of the vertical pieces.
This has the effect of all the pieces keeping their constraints, but the group looking like an exploded view instead of a window frame of a different size with the same dimensions on the lumber and glass thickness?

How can I make it so scaling acts as desired?

You can set your Pivot Point for scaling from a certain Point instead of your Objects origin - maybe this is what you're looking for... (it's a little Icon on the 3D views Header bar at the bottom).

changing the origin changes where the objects scale from, but I can't find a way to make it keep the parts attached.  It seems like I'd need an attachment constraint.  But so far what I was able to find in that area seems to nullify the scaling constraint.

Maybe some Screenshots may help to explain your situation/problem a little better? Greenshot is a great tool to capture some... (with a direct imgur-upload)

Added screenshot of objects before scaling, and after scaling with restricted dimensions.

@shanemgrey could you include a screenshot of your desired result? I believe the answer to your problem is Local Transforms, but I'm not certain what you're trying to achieve.


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Two bones acting as one
So I was trying to rig a Dino model from a ps1 dev disc. I used rigify, and for the tail I used one of the arm presets. I didn't make sure alot of bones for smooth bending, but some sets of bones are acting as one, making the problem even worse. Here's the example:

Any way to fix this?
Edit
If I do have to redo this, is there anyway to get the 'arm' to have more bones so I can have the nice inverse kinematics?


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How to see whats beyond the video sequence editor

Is there anyway to see movie strips outside of the video sequence viewer? The image on the left side is my normal view. The picture on the right would be an extended view. Basically I have rolling pictures on the bottom and they come on and off the screen right from left. How do I see their position when they are not in the viewer. Its important for the timing of scrolling that happens for each image.

You may choose to do some of the scrolling in the 3D View first to produce an image sequence, then  later used in the Blender Video Sequence Editor, VSE.  The 3D View can show objects not in the camera.
As another example if a Blender User wanted to have fancy 3D titling that would be created in the 3D View first as an image sequence first.  Simple titling is available in the VSE.
By using planes with a texture and a camera with orthogonal settings you camera will behave more like the VSE.  The texture is the movie or image sequence that has already been created.
I tend to have two scenes.  SceneA, 3D View and Post processing No VSE.  SceneB, VSE only.

Thank you with your thoughts. I am going to play around with those ideas. But maybe the creators of blender could add that in the future. I adjusted my workflow and understand key frames to perfect the timing.


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Insert Reverse Pose Pasting Flips Everything
I'm working on a simple walk cycle but when I hit Ctr+C on pose I want inverted and then Ctrl+Shift+V it throws the characters arms up towards the sky and flips the joints of the knees backwards like a flamingo. Giving it the appearance of falling backwards instead of walking forward. Is there some way to get this fixed?

I have all the bones named opposite i.e upperArm.L and upperArm.R for the life of me i can not figure out why it would do such a thing


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Move CENTER (not pivot) to SELECTED array of (edges, vertex, faces)
I was reading this and this about switching the pivot point.
And I managed to reproduce its 4 steps:
bpy.ops.mesh.primitive_cube_add(radius=1, view_align=False, enter_editmode=False, location=(0, 0, 0), layers=(True, False, False, False, False, False, False, False, False, False, False, False, False, False, False, False, False, False, False, False))
bpy.ops.object.editmode_toggle()
bpy.ops.mesh.select_all(action='TOGGLE')
bpy.ops.mesh.select_mode(use_extend=False, use_expand=False, type='VERT')
bpy.ops.view3d.snap_cursor_to_selected()
bpy.ops.object.editmode_toggle()
bpy.ops.object.origin_set(type='ORIGIN_CURSOR')

So the logical question is: Can we get it down to 1 "keybind"?
The usual workflow should be:

I change from object to edit mode.
I select "VERTS" to grab different points between what I need to place the CENTER of the object (the purpose of this is that every time I want to manipulate/rotate/translate) this object, those selected vertices will have the TRUE center of the object in LOCAL mode.
I choose "CENTER to SELECTED" (from somewhere/my function/addon, etc..)
(internally blender moves the pivot to selected, changes (snaps) the CENTER to pivot, and then returns the PIVOT to the center of the world. The idea is that the PIVOT will not get lost or in the way once it has completed its task).
The center of the object gets placed between the selected vertices (or edges/faces).

Is it possible to do this on a code or addon?
Thanks.

An object can only have a single pivot point. There is no center available. For what you are trying to do, we have the 3D cursor.

Bmesh version
The origin is local coordinate (0, 0, 0)
In local (vertex) space the selected location vector o is the average of selected vert coordinates   Make that the origin point by subtracting vector o from all verts' coordinates.
Then move the object to counter the shift in local coords.  The vector t  is the equivalent global space translation, of local space translation o.
Test script. Edit mode. Select verts, run script.
import bpy
import bmesh
from mathutils import Vector, Matrix
context = bpy.context
ob = context.object
me = ob.data

bm = bmesh.from_edit_mesh(me)
selected_verts = [v.co for v in bm.verts if v.select]
# average of selected verts
o = sum(selected_verts, Vector()) / len(selected_verts)
# make this the new origin
for v in bm.verts:
    v.co -= o
# move the object

mw = ob.matrix_world
t = mw * o - mw * Vector()
mw.translation += t

bmesh.update_edit_mesh(me)
me.update()

I found stuff. Posting for everyone.
bl_info = {
    'name': 'Move origin to selected',
    'author': 'PSchiller',
    'version': (0, 0, 1),
    'blender': (2, 7, 9),
    'location': '3d view > space bar > Origin Move to Selected',
    'description': 'in edit mode, sets object origin to the median of selected verts/edges/faces',
    'wiki_url': '',
    'tracker_url': '',
    'category': '3D View'}

import bpy

class MoveOrigin(bpy.types.Operator):
    """Tooltip"""
    bl_idname = "object.origin_to_selected"
    bl_label = "Origin Move To Selected"
    bl_options = {'REGISTER', 'UNDO'}

    @classmethod
    def poll(cls, context):
        obj = context.active_object
        return obj is not None and obj.mode == 'EDIT'

    def execute(self, context):
        saved_location = bpy.context.scene.cursor_location.copy()
        bpy.ops.view3d.snap_cursor_to_selected()

        bpy.ops.object.mode_set(mode = 'OBJECT')
        bpy.ops.object.origin_set(type='ORIGIN_CURSOR')
        bpy.context.scene.cursor_location = saved_location

        bpy.ops.object.mode_set(mode = 'EDIT')
        return {'FINISHED'}

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

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

if __name__ == "__main__":
    register()

hahahahahah.- awww this is amusing. I am the author of the addon, and this is one of the answers to the .py script.
Cool, @Mr Zak, now can we adress the issue on how do I keybind 2 commands in one? -Thanks.


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Constant interpolation with Noise Modifier
I am trying to create a curve in the graph editor with my interpolation set to constant and a noise modifier added.
The noise modifier seems to only generate curved lines. I need them to be constant. I want 0 interpolation between the points, is this possible?
I am trying to generate a random transform over a period of time for an object. But i need it to be constant, no interpolation between the transforms. Maybe there is an easier way to do this.

Consider baking the noise with the respective step size, then set the resulting keys to constant.

@Leander Can you add this as an answer with more detail. I will try it and give a point if it works too.

@Not necessary, Rich's answer is better and simpler.

I believe you can achieve what you desire by using an additional modifier after the noise - a Stepped modifier.

The Noise modifier generates the 'smooth' noise while the Stepped modifier breaks the curve into distinct bands (Step Size) and keeps the value at the same value for the duration of that band.

Exactly what i needed. ty


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Textures and materials to show up while playing animation in 3d viewport
I am trying to get my textures and materials to show up in the 3d viewport while playing the animation of my scene. The textures and materials are showing in my 3d viewport. However, when i play the animation the objects do not move until i stop the animation.
Right now i have my method to display objects in the 3d view set to rendered. If i have it set to anything else, the textures and materials go away and i only see the blank objects, but they will move with the animation.
How can i get the objects to properly animate in the 3d viewport with textures and materials applied?

Clarification:
I press alt+A to run the animation. The animation plays, but none of my objects move like they are supposed to. Then i press alt+A and the objects jump to the location they are supposed to be at the frame where the animation stopped. I want the animations to move like they are supposed to while the animation is playing. I can stop through the animation using the timeline by pressing left or right arrow and the objects move. But i want this to work while playing the animation.
Thanks

@MrZak Added clarification.

@cegaton I have a plane that moves from left to right that has a material and texture applied to the surface.

When using the viewport in render view mode, sluggish animation and freezing are not uncommon when you try to play your animation. Try setting the viewport render mode to "material" or "textured" and you should be able to play animations smoothly with your textures/materials visible and animated.
This has one caveat however, the Blender Internal render engine does not support procedural texure in material view mode, and will display the object incorrectly.

I have already tried that, i mentioned it in the question.

Ah right I see that now. My mistake.

no problem, easy mistake

I've done some searching. It appears that Blender Internal does not support procedural textures in the viewport. If I create a material and give it a texture however, it shows up and animates correctly in material view. As soon as I mix in a procedural texure however, the material breaks in the viewport.


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Exact same mesh and UV's, one scaled minus one, and UV's started to strecth
I'm a beginner 3D modeller, and I have been having issues with my recent work. I'm not exactly sure if the issue caused after I scaled it. I've been working on this project for quite some time and noticed the problem after texturing. I was making stairs for a tower, since stairs are mostly repetitive I was continuously duplicating, flipping etc.
So the ones I scaled -1 in X axis appear stretched like this. Their tangents and binormals appear different in unreal engine too.

And Blender's angle based  stretching overlay looks like this. (Normally they are overlapping. One in the left is working correctly, right one is  stretching.)

Edit: I just checked if they are identical with overlapping both and adding boolean modifier. Although they look quite similar they aren't %100 identical. Probably at some point I messed up. Although I would still love to know how I could solve an issue like this without just going back and start replicating again.


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Weight painting in rigging and particle systems combined
I modelled and rigged a rabbit. There are many vertexgroups name-connected with the bones. One of the groups is the head and the eyes are included. I made a separate vertex-group for the eyes eventhough they are not connected to the armature but it is just handy to be able to select them (for texturing eg).
The eyes move with the rig when they are joined to the mesh. But when I apply a particle system (hair) to the head they are also planted on the eyes. So when I then weightpaint the eyes blue in the head, the particles are gone but the eyes don't move with the rig anymore.
So the weightpaint seems to conflict for rigging and particle systems? Is there a way to separate weightpainting for particles and for rigging?

Solved it! There was one thing I forgot to try and that was adding bones for the eyes. Eventhough I did not plan to animate the eyes this probably is the only way to do it. Made 2 eye bones and 2 vertexgroups with the same name. The eyes move with the rig now and there is no hair on the eyes.


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Offsetting tracer particles in a fluid simulation
I am working on an animation where I am using fluid tracer particles as a smoke flow object, and I have run into a problem. To get an idea of what I am trying to do, see my test render (of a simpler scene) at https://youtu.be/NovKf-hDN48
Basically, I have a fluid with tracer particles that are on fire. And of course some dynamic paint going on and stuff , but that is not relevant to my question.
Anyway, I need there to be many parts being set alight at different times (so multiple separate fluid domains), and while it is easy to use Offset to start the different fluid sims at different times, I have found no way to translate this to the tracer particles. They will always start off at the first frame. I cannot set different particle systems on fire (with the smoke simulator) at different times.
Does anybody know of a way to get this to work? Even a crude workaround would be helpful.
Edit after more experiments:
The obvious workaround is to set the inflow objects to start at different times (by keyframing the enable property), but apart from the fact that this doesn't work (see below), even if it did, I would have to rebake the fluid sim for any small change in timing, which is cumbersome to say the least.
And yes, there seems to be a bug with the tracer particles, so if the inflow object is not enabled at the beginning of the animation (frame 1) the tracer particles won't work at all. They just don't appear with the fluid when the inflow object gets enabled.
My workaround for the time being (for whoever runs into this problem in the future) is to have the inflow objects enabled for the first frame, and then disabled until I want them start for real. Then hide the fluid particle object until the particles are supposed to be seen.
Still, even with this workaround, I would be happy to hear if anyone has a smoother solution. Yeah, I realise this is quite a niche problem...

Hi Jbergman, I think I got it. Are you still active here? I'm quite busy this days, so I'm not going to post it right now. The solution is a little cumbersome but is not difficult. Actually, after realizing it, I just decided to go on and don't use particles at all in this shot.


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How do I force Graph Editor to show drivers for my Materials
I've rigged this face, adding drivers to shape key values and particle systems. So far so good, but when I add drivers to some node values they don't show up in the Grap Editor when viewing Drivers.
If I create an new empty scene and try to reproduce the issue, it's working as suspected. The material show up beneath the object, and I can expand all the driven inputs.
It's just not working in my previous scene with the face :(

Related: is there a caveat to using drivers on node properties?

There is a cursor icon in the graph editor header that enables only show selected objects, which means the driven node needs to be selected to see the driver.

I know, I had the mesh selected and saw my other drivers like shape key animations and particle values. Just material or node values that had drivers did not want to show up.

Ok I was stuck there, but removing the drivers back and forth, and adding them not on the node but on the N-panel value forced the Graph Editor to update and I could see the drivers there.


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Can I access the render screen size in a custom filter 2D in the game engine?
I am using Blender Game Engines Filter 2D to make a post effect with GLSL.
In an fragment shader applied on the frame buffer, I want to access the size in pixels of that buffer in GLSL.
uniform vec2 screensize;

This is possible for objects of the type BL_Shader
shader.setUniform2f("screensize", w, h)

The viewport size can be accessed in this way
import bge

w = bge.render.getWindowWidth()
h = bge.render.getWindowHeight()

print (w,h)

But I don't know how to get the BL_Shader object. The SCA_2DFilterActuator does not have any reference to such object.
co = bge.logic.getCurrentController()
distortion = co.actuators["riftDistortion"]

All the game properties stored in the object that calls the Filter 2D are passed to the shader as uniforms. So if you have a width and a height float game properties you can set their values at run-time to match the window size.
However, be aware that the window size (which you get from render.getWindowWidth() or render.getWindowHeight()) is not the buffer size. The buffersize is the closest power of two for that dimension (e.g., a window that is 1024 x 768 will have as buffers 1024 x 1024).

That said, I can't see why do you want to access the size of the buffer in pixels. You are much better of by using the normalized coordinates of the visible part of the buffer. You get this with gl_TexCoord[3] link

Thank you, gl_TextCoord[3] helped. I am also able to set Uniforms with Python. I didn't know that the buffer size differs to the screen size, interesting. I am trying to achieve a optical distortion inversion for the Oculus Rift, the screen size is needed to achieve that. I actually have another question related to that.


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How to clear values in measurelt (Toolpanel>display))
I am using helplines to determine the outer angles of the cylinder. I need these angles to align the cubes exactly to the cylindersides. Measurelt puts values on top of each other however, making them unreadable (see image) Is there a way to clear these values (then I can also get rid of the light blue angle font which is hardly readable)?
And if there is an easier way to align these cubes tot the cylinder I would like to hear that too. I know I can duplicate the sides of the cylinder and make them into cubes with the right angle, but that is not what I want.

Can you make Snap + face + active + align rotation work for you? You may have to fill some faces temporarily, just to create guide planes. Thereafter, translations in 'Normal' space or in custom orientations should work? Even then, it still looks as if circular arrays should be of use. Beautiful model, BTW

Not forgetting you can snap the cursor to a surface, align your view to a face, and create objects aligned to view. Not forgetting either that you can create the glass  from the frame, in place, by duplicating some of its edges?

Perhaps a quicker way to do this particular job is with an array?

Create your 14-sided cylinder at the origin.
Create your cube at the origin
In Edit mode move/scale the mesh of your cube to  your desired position with respect to one of the the cylinder's faces (probably down X in your example).. leaving its origin behind.
Create an empty at the origin
Assign an Array modifier to the cube with 'Object Offset' and the empty as target
Rotate the empty in Z, entering '360/14' as the angle
set the array count to 14

You can then select the empty and the cube array together, and translate them in Z to adjust the vertical position of the cubes. and if you edit the cube, all the arrayed instances of it will be edited too.
If/when you need the cubes to be independent, you can apply the modifier.

Thx Robin for your extensive reply. But my first image was just setup to test how to do this. I just added a second image with the true problem at hand. Sorry for the confusion As you see I want to fit glass in the window frame that has the same angle as the window (or wall). When I created the building I had no idea what kind of windows I was going to put in later on. So I need to find a way to determine the exact angle for the glas pane.

@TaaskePrins ahhh, OK. Personally. I still think it's better when modeling to think like a  carpenter .. after a few initial numerical measurements, take all angles and lengths from pieces you already have.


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Eevee vs Cycles on tinted glass
I made a test scene with a windowframe with glass, glass without a frame and a solid cube. Sun is the main light source with a little bit of HDRI lighting in the world settings. In cycles the tinted glass casts a colored shadow. In Eevee the tinted glas does not cast a colored shadow.
Next, you can see that in the Eevee image the cube casts the same shadow as the left glas plane. In Eevee I cannot set soft shadows for the glass in the light settings or the  render because that also blurs the shadow of the windowframe. So I can only do this in the material tab (or nodes) and that does not seem to work; glass shadows are either opaque or completely transparent. I used Princ BSDF and Transp BSDF with a mixed shader.
I have 2 questions:

Is it possible in Eevee to make tinted glass cast a colored shadow just like in cycles?
How do I set the glass shadow soft (but transparent) while keeping the window frame shadow opaque in Eevee?

Cycles:

Eevee:

For #2 you want an area light. An HDRI background does wonders to realism.

Tried that in different configs with Eevee, but couldn't get transparent soft shadows, The shadows are then either opaque or very diffuse/blurry. Best results I had sofar in Eevee is a combi of sunlight with very low strenght HDR world background (0.05). That is what you see in the Eevee image. There is however no difference between the shadow of the solid cube and the left glass.

Pretty easy faking colored caustics in cycles mixing a transparent shader and a Glass/Principled Shader with these nodes.

However that trick does not work in EEVEE

You could create it by using a color ramp on the surface material or a projection of color on the shadow if it's a still image it's a crude hack that changes the surface instead.
like this:

This trick maps the shadow area to a different color.

Thanks for your contribution.  Please be aware that answers are moderated and while this attempts to answer the question, there is very little expanation to go with it.  Please use the edit function to provide additional information.

..Agreed. In principle, a really nice answer with interesting methods. Just a word or two explaining how they work would be a great help


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beta 2.8 screen capture
How to make a screen capture video in 2.8 beta? In 2.79 the screen capture shortcut was Alt-F3. Is there an alternative way in 2.8 beta? (The screencast is in the Window pulldown and has, as far as I can tell, no shortcut.)

In Blender 2.8x, every menu item that doesn't have a shortcut can be assigned one very easily:

right click on the menu item, then
either select

Add to Quick Favorites: your quick favorites will be available under theQ shortcut for quick selection
Assign Shortcut: you can now assign a custom unique shortcut.

I think the developers have made sure to leave F4 to F10 unassigned ("minimal keymap" philosophy) so that you can use these keys as custom hotkeys.

Thx for the answer. But my issue is foremost the screen capture possibility. I edited my question to make it less ambiguous.

I'm not sure I understand. You mean a video screen capture as opposed to a still screen capture?

Correct. In the manual it is called screen capture (video) as opposed to screen cast (still).

Oh sorry then. I thought you could find your functionality and all you were missing was the shortcut. I'm not sure I can help with this as I use external applications for screencasts (mostly for answer to posts)


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Writing rendered image to file (C++)
I am trying to modify a little bit the source code of blender to fit it to my needs. Does anybody know which function is responsible for saving a rendered image to file?
Thanks in advance.
What I would be interested in is how to invoke the whole 'saving image' procedure, which is called for example after every frame in rendering an animation. I just want to call such a function in the process of rendering.

Have a look into source/blender/imbuf to add a new format and source/blender/editors/space_image/image_ops.c to edit how blender saves the image. Also this old diagram from the wiki should help. You can also try the official IRC channel.

Are you sure you need to go as deep as source code? I've made loads of post-render things using python and app handlers https://docs.blender.org/api/2.79/bpy.app.handlers.html

Those handlers might be a solution, unfortunately, I don't know how to save currently rendered image from handler call. When I use function bpy.ops.image.save() I get the error: RuntimeError: Operator bpy.ops.image.save() failed, context is incorrect. Any help?


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Principled Shader - blue subsurface color for thin parts
I am traying to render a character in blender. I am using Principled BSDF.
As a subsurface emthod I am using Random walk, since it gives more realistic results. Whole face is fine except eyelids. They become blue. I guess it is due to thin geometry. Any Ideas How to solve the problem?

--Edited--
Here is shader graph:

As Base color I use orangish colored texture. SubsurfaceFactor is a gray scale map. I used original Subsurface Radius values (1.0, 0.2, 0.1) multiplied by black color to steer the radius easily.
I get this thin geometry using boolean modifier. I subtracted eye shape from teh face shape to prevent flesh appearing in cornea.
Another problem are those strange speckles in shaded area? Does anybody know what cause them? I had same problem when I worked with Arnold Render, so probably something's wrong with my setup.

Could you tell a bit more about your shader setup and maybe show the nodetree? What's your subsurf radius vector?

I am experimenting the same thing (the blue color on thin surface). I think it happens when the thickness is under the blue color radius (or the color -red green or blue- which has the min radius). Maybe we could play with inverted ao to reduce the sss scale on these thin surface (Not tried yet)

My 2 cents tweak to avoid blue patch on thin surface:

I adjusted the distance of the ambiance occlusion to be small enough to be near to zero on thin surfaces.
I disabled "only local" to prevent collisions with external objects to also add blue color around the collision surface.
Here is how my ao values look like:

As a result, from this:
... to no more makeup:


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How can I make Eevee renders more realistic?
I'm struggling with a scene that contains different kinds of materials (metallic, plastic, painted walls, cemented floor ...etc) it looks awesome in Cycles but when I switch to Eevee the scene looks dull and totally unrealistic (not even remotely looking like Cycles). Now I'm aware that there are certain parameters that need to be enabled first, but I think I enabled pretty much everything, i.e "Screen Space Reflections", "Ambient Occlusion", and "soft Shadows" I also cranked up the Samples and enabled "Screen Space Refraction" on each and every material in the scene (even though there is no see-through objects in the scene) but no real results so far.
Is there more to that to achieve that nice fake realism in Eevee?
EDIT: Ok attached are the renders and the settings I use for Eeevee

EDIT: Find below the blend file and the splash screen of the build.
http://www.mediafire.com/file/cqage42th8l9829/Reproducing_Error.blend/file

Maybe screenshots will help a bit.

I agree with Sgslav. It'd be easier to help with specific things if we can see your scene.

eevee and cycles mostly give a similar result, but it requires to make the scene work for both engines' specificities. To me it looks like you didn't adapted the lights objects (they don't work the same way in both engines). Might also be a bug in your build. Providing your file might help sorting that out faster.

Just added the blend file and the splash screen of my build I'm using.

I'm digging in. By the way, your build is quite old, You should update. As 2.8 is changing every day, things can be quite different from one day to another.

Well, I digged a little bit inside your .blend file.
The first thing I noticed is that you are in Look Dev shading, which isn't the Rendered shading:

Even though they can give similar results sometimes, you really have to get into Render shading to have a fair preview of your render.
In your case, just switching to rendered mode already makes a huge difference, you'll get a much closer result to cycles.
Also, I didn't get your HDRi embedded in the blend file, which gives me a pink render result, so I had to remove it in order to do my little tests.
The first thing I did was playing with your Sun's settings, precisely the Shadow Clip Start/End and Contact Shadow Distance. This is really only to "fit" the Sun properties to your scene. Look how the shadow looks when you change those settings, especially in walls' corners.

Once it's done, there is really only one thing to do: give Eevee what he needs to calculate your Indirect Lighting. If you're used to Cycles' raytraced physically unbiased lighting calculated on the fly, Eevee doesn't do that. It's closer to a video game engine: it will try to calculate things only as few as possible, and only where you want and when you ask him to do so.
So basically, you need to create at least two things: cubemaps and irradiance volumes. Those two objects can be found in the "Add Object" menu (Shift A) under the Light Probe submenu:

Place at least one Reflection Cubemap in the center of your room. For the irradiance volume, make sure every little orange dot is inside the room. If you intend to only show the little area with the shed, you can scale the irradiance volume to cover this area only, that would optimize your resources.
Once it's done, you just need to bake those indirect lighting informations. Head over to the Indirect Lighting panel of your render settings, and hit the "Bake Indirect Lighting" button. It may take a while.

And this is what I obtain just with those steps (cycles up, eevee down):

If you want to know more, I suggest you to do some research about Eevee and indirect lighting. There are also some videos on youtube where people convert their old Cycles projects to Eevee.

Thank you for such a thorough answer, I had been looking into indirect lighting before posting the question tbh but I nevertheless felt that my Eevee scene should look better even without IL, I will l research further, thanks again!


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Rendering World Position Pass
I need to render a world position pass in Blender to check if my idea is correct. I found solution that uses an emissive material and geometry node to render position as colors: How to render world position pass

When I render the scene presented below:

I get this result:

The image seems to look fine, but when I check the values with the image view something's wrong.Each cube is size of 2 and spacing is equal 1. Cubes are translated in x direction and the first-left one is placed in origin.
I assume then that the first-right cube should have values of R component within the range 12-14. Intead of that values are around 2.7.  What do I do wrong?
---EDIT---
I did everything as Martin recommended. Anyway I still have same problem:

I attach the .blend file where the problem occurs. I will be very grateful if you find the problem:
https://drive.google.com/file/d/1bMnmEB9-j2OQllZKqfwwWkgx2ZlvTFx3/view?usp=sharing

Color management?

Any tips, what I should set in color management? I tried a lot of variants. The most logical one would be Raw mode in my opinion. There is no one named 'linear'.

Try setting Display Device to 'None'(because you do not want it to be an image viewd on any display device, but only pure unchanged values) in the scene's color management settings:

Seems to work:

Obviously the output needs to be a 32bit full float EXR image in this case as well if you want to save it.


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Filling in Grease Pencil Shapes via Python Script
I am trying to fill enclosed shapes in Grease Pencil using Python Script, as if using the fill tool. There seems to be a Grease Pencil operator, but I haven’t been able to figure out how to use it in the script (bpy.ops.gpencil.fill()).
Any help would be much appreciated.

bpy.data.grease_pencil["GPencil.001"].palettes["GP_Palette"].colors["Color.002"].fill_alpha = 0.6

-should do the trick.
Hover the mouse of the Fill -> Opacity slider in the properties panel(N)
and take a look at the command that shows in the popup. Change the names
of the "GPencil.001" and the "Color.002" to the ones that the command is pointing
to(the ones you are using).


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Plastic bottle material
I want to make bottle as this one, but i cant find anyting like that. What is node material for that? I need transparent plastic material

What specifically are you struggling with?

Is it your question about using Glass Shader?

It looks like you are searching for something like this: https://blender.stackexchange.com/questions/74686/how-to-create-clear-plastic-cycles
Maybe you can try this material and change it the way you want

In Principled shader, I think that you can get a very nice approximation with transmission at 1 and roughness way down.

If you are using 2.8, I found that the principled shader is very easy to set up for this provided you make use of an environment texture in the world shader.


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Baked texture map shows weird distortions, is it mistake or not?

After i baked diffuse map i got these weird distortions, but i don't know if i should worry about them and unwrap mesh differently.

You are subdividing your UV map with a subdivision modifier.
Go to the subdivision modifier and uncheck UV Smooth, if you don't want to subdivide the UV map.
From the manual:

UV Smooth
  How to handle UVs during subdivision.


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Properties Editor: How to change short to int for "Pass index" button in Relations?
I am numbering objects in my scene with the help of "Pass Index" button.

.
Apparently this button is short and it can not be set to  more than 32767 objects in the scene. I would like to change blender source code to be able to set more objects. I found file in which this property is declared: "DNA_object_types.h" (struct Object -> line 252: short index; /* custom index, for renderpasses */.)
But once I change it to int, program will not compile and will give me a lot of errors. What is the proper way to change short to int for this button? How actually rna_object_gen.c is generated? I read through rna and dna articles, but I still didn’t get an idea how to change this short to int. What are the other places in the code which I need to change?

Do you have a legitimate use for having more than 32k pass objects to differentiate from? Consider if you really want to use object pass for your case, you could easily set up a new custom property per object.

Changing that property could be horribly complex - depending on what else uses it, what records and structures also use it, what else is dependent on it, etc. Only by tracing through the code (and effectively debugging all of the errors reported by your failed compile) will you be able to determine what needs to change - and each change may also be depended on other changes and further dependencies. As @kheetor quite rightly suggests, it might be easier to work around the problem in other ways than trying to change this.

Thanks for answers. I found a solution, everything works for now, but it should be tested more in the future.

Instructions:
1) Read useful info on following websites:
RNA, Property, DataApi.
2) On this websites blender guys give description how they are creating their gui. Description is not very easy to understand, but following sentences gave me an idea, what is wrong, when I try to convert button from short to int.

More later about saving and loading, what we have to be careful about in the DNA files is alignment. For compatibility between different compilers and platforms, all members must be aligned correctly. The general rule is that if the size of some member variable is n, it must be defined starting at a location in the struct that is a multiple of n. For example ints must be defined at locations that are a multiple of 4. Structs must be created at locations that are a multiple of 8. If for some reason this does not work out, padding variables can be added in between (usually named pad, pad1, ..). Alignment errors in DNA structs will be printed during compilation.

This is exactly the error, which I was getting, when building the program with my changes.

Align 4 error (32 bit) in struct: Object col[4] (add 2 padding bytes)

Then I have noticed that all over the code in the "DNA_object_types.h" developers were adding padding variables (void pad, char pad1, char pad2[3]...) for the aligning of the memory.
3) So when you create additional property or variable in DNA, you should align it properly. More on alignment you can find in the file "dna_genfile.c".

IMPORTANT:

do not use #defines in structs for array lengths, this cannot be read by the dna functions
do not use uint, but unsigned int instead, ushort and ulong are allowed
only use a long in Blender if you want this to be the size of a pointer. so it is 32 bits or 64 bits, dependent at the cpu architecture
chars are always unsigned
alignment of variables has to be done in such a way, that any system does not create 'padding' (gaps) in structures. So make sure that:

short: 2 aligned
int: 4 aligned
float: 4 aligned
double: 8 aligned
long: 8 aligned
struct: 8 aligned
the sdna functions have several error prints builtin, always check blender running from a console.

After I have added padding variable, "Pass index" was finally converted from short to int.


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Multiple artists modelling the same file
I am looking for a workflow that allows multiple artists to work on a project where users can work in parallel and assuming they don't change exactly the same thing the work can be smoothly merged.
I am used to working with a game engine using xml and many separate binary files which works well with a versioning system like git or svn.

"assuming they don't change exactly the same thing"? There are alot of other things to factor in. Possible duplicates of Does Blender support any form of collaborative editing? and Does Blender have a file locking feature?


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Hair particles don't follow armature deformed mesh
I have a mesh with a hair particle modifier on it along with an armature that is animated using the Wiggly Bones plugin.
However, when running the animation, the hair kind of 'detaches' from the mesh, and don't follow the deformation nor rotate or do... well, really anything. They kind of flow up and down but all at once and never moving around either.
I have already checked that the particle modifier comes after the armature modifier, as pretty much every other thread about this problem on the internet suggests.

If I turn off Hair Dynamics, then the particles will follow the mesh deformation fine, but of course do not animation at all. It's when Hair Dynamics is turned on is when this weird behavior starts.

I have also tried (and tried and tried) running Bake All Dynamics under the cache tab with no luck.
What am I doing wrong?

Frame 1:

Frame 17:

Frame 23:

and so on.

I'm beginning to think this is a bug, actually. Would it make sense to submit it on the tracker?


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Blender(cycles) fails to render correct values in some pixels. Fails to hit correct triangle. Why? And how to avoid this problem?
I do some rendering in blender(cycles). I render with the help of cycles nodes .exr images, where in each pixel instead of rgba-channels I store xyzObjectIndex-channels. Everything works fine up to several pixels.
For example, on the image above you can see visualization of the object ids. Each pixel has information onto which object it looks now. You can see that blender failed to recognize building in one blue pixel, blender suggested that this part of the building is the sky and has rendered sky there.
As I can see this happens for degenerate triangles, triangles which are almost in parallel to the ray, which is shoot from pixel. It means that blender(cycles) raytracing algorithm fails to detect correct triangle when shooting ray.
Material setup:

This nodes help me to render .exr image, where instead of RGB I have XYZ - 3D position of the surface seen by pixel and instead of alpha - Object Index. Rendered image is correct up to a few pixels.
Geometry of the mesh: As far as I know my mesh consists from triangles.
Rendering machine: I use SVM.
Samples: one ray.
How to avoid this problem?
P.S.:
Also noticed that function ray_triangle_intersect() in file "\cycles\util\util_math_intersect.h" returns sometimes wrong barycentric coordinates (u + v > 1, which is wrong), hence it renders incorrect 3D position for current pixel.
Wrong barycentric coordinates are there due to fact that in line 182 (const float inv_den = 1.0f / den;) they have division by zero.

In order for someone to help, please provide more information such as the geometry of the meshes involved, material set up, anything else relevant to your scene - currently all we have to go on is the results of your render. This would make it hard for anyone to replicate your problem. It would also help if you could provide a simplifiedand self-contained  .blend (with any images ‘packed’) that exhibits the problem.

Question is partially answered at developer.blender website


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3D Printing Obj's with Material from Blender 2.8
So this may be answered elsewhere (I see plenty of questions of 3d printing with Textures exported) but I think this is slightly different as I'm talking about a fancier printer that can do colors.  Let me explain:
My printer can do this:
This was originally a .vrml that came from photogrammetry, but it can do it with .obj too.
Now lets say I'm in Blender and I start with the basic cube and add a material to it:

In this case the material was from BlenderKit, but I don't suppose that should matter where it came from.
Now if I were to export that cube as an obj (or a vrml).... how do I get the material to be exported with it? I see the checkmark where it says "Write materials" and that does technically create a .mtl file to go along with it, but its 0 bytes and blank. I've seen rumor I might need to "bake" something?  Is that true? If so, I did these tutorials:  I felt like I was almost there with this tutorial or this one, but when I finally "baked" and exported... the mtl file was larger, but it still showed up blank in my printer, it then said it was looking for an additional texture photo.  Does the baking not export the texture photo?    When I've loaded obj's or vrmls into my printer software before it only needed one additional file (the mtl usually).

Additional info, the .obj file that created that kids head above did not need any additional .mtl or texture photos with it.  The printer program opened the .obj by itself and it contained color.   How can Blender export an .obj with the information contained within.

"Does the baking not export the texture photo?" It does, exporting image file is the primary reason of baking. "The printer program opened the .obj by itself and it contained color" This sounds like .VRML file you tried to print had vertex colors (which is especially the case for models created with photogrammetry). In that case you need to find a way to bake your material to vertex colors. In anyway, comparing file which yielded good result with not working one could help

@MrZak I double checked that and it was definitely an .obj.   How would you bake your materials to vertex colors and export an obj?  Well or honestly I'll export a vrml too I don't care, but how do you bake the vertex colors?

If that was OBJ then it's not necessary you want to export vertex colors.. Not all applications can export them into OBJ, many of them can't (ZBrush as exception, MeshLab seems to be able, see https://gamedev.stackexchange.com/a/21304) so if you really want OBJ then your first file probably used something else instead of vertex colors. As to baking - old way was Blender Internal, for new one see https://blenderartists.org/t/2-8-bake-to-vertex-colors/1144425


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What's the difference between DEF bones and ORG bones in functionality?
I have downloaded a very nice, fully rigged, character model and have embarked on studying this file and doing some tests. However, from the theoretical POV, I can't seem to grasp the difference between DEF bones and ORG bones in that file. The file is "Mr Incredible" from Blendswap, all credits go to "Crias" the author of that file, not sure if I am allowed to re-upload his file here.
But in theory, how does each bone function and contribute to the rig? considering that a MCH bone is for mechanism, DEF for deformation, CTRL for Control..etc, I'm aware of the terms and functions for each type, except ORG, don't know if it's a sub-type of DEF or I got it completely wrong.
EDIT: Sure, here's a screenshot of the selected ORG bone:

It lies within another bone named "Shoulder.L" and this bone does deform the body upon rotation:

You do not need to upload the file.  You can show a screen capture to make your question clearer. You can show part of the screen capture to make your question clearer.  You need not show the entire file.   Blender or Free GIMP can obscure part of the screen capture to reduce unnecessary details.

ORG - prefix for original bones from which the full rig is generated
DEF - prefix for bones contributing to deformation
Usually the ORG bones of the metarig are replaced by generated bones, but in this case the clavicle is used from the original rig and contributing to deformations.
This IMHO is a mistake and should be marked right, a copy of that ORG bone should be generated and marked DEF and the ORG bone moved to a hidden layer where rest of the org bones are lurking, ready to be tweaked and a new full rig generated from them again if needed. If both are the same bone, you do deform the mesh while tweaking the metarig and this is not wanted, the mesh should stay intact. If the org bones are in a separate armature (like with rigify), there is no need to have ORG prefixed bones inside the rig at all.


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How to make 3D volumetric textures in Blender?
So let's say I want to make some volumetric fog or something like that. I saw a demo of how to do that in Blender recently, but it relied on the built in 3D textures built into Blender. How do I make my own 3D textures?
I'm very new to volumetric stuff so maybe I'm not even using the right terminology. Any clues?

Thanks @cegaton So would it be correct to say that the only way to make 3d textures is procedurally?

@cegaton right but if you use a 2d texture it's not going to be the same as a 3d texture. 3D texture has to be procedurally generated correct?


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support for instantiation
What is the best approach to building up a complex scene or object in blender composed of previously modeled .blend objects?  I have heard of linking the objects from another .blend file, but then all I get are untextured primitives (not to mention not being able to instantiate composite objects without losing the relationship between the composite parts). For example, I hope to instantiate entire .blend models (less the lighting and camera), not just components of one.

trying to clarify... I want to place a half dozen discrete .blend models at various positions in an empty .blend model, arrange those components geometrically and subsequently embellish that arrangement by adding more objects in the parent model, in a technique commonly known as hierarchical design.
I don't want to lose textures applied to component objects (in their individual .blend files) nor do I want to lose the relative position of components within contributing .blend files, e.g. an arrangement of rectangles should look exactly the same instantiated as it does within the defining .blend file.
In hierarchical design, instantiated objects are 'read-only' copies of the constituent models.
trying to clarify... I want to place a half dozen discrete .blend models at various positions in an empty .blend model, arrange those components geometrically and subsequently embellish that arrangement by adding more objects in the parent model, in a technique commonly known as hierarchical design.
I don't want to lose textures applied to component objects (in their individual .blend files) nor do I want to lose the relative position of components within contributing .blend files, e.g. an arrangement of rectangles should look exactly the same instantiated as it does within the defining .blend file.
In hierarchical design, instantiated objects are 'read-only' copies of the constituent models.

Sounds like you're looking for linked groups?

as long as the materials in the source blends are set up correctly, and you set the source and target scenes to the same render engine, the textures shall not be 'lost'. Also the positioning shall carry over. What you're asking for is possible with - as stated by others in this question - linking groups.

You question is very vague and hard to answer.
In Blender you can link or append various types of data, this is visible when you browse to append or link from other files, and you can choose from Object, Meshes (object Data), Cameras, Freestyle, Groups, Materials, Node setups etc.
Depending on the type of object you link, you'll get different results that can sometimes be overridden.
Linking object data like meshes, curves, cameras etc, will only bring in that data alone (raw mesh data without modifiers for geometry), whereas linking an object will also bring with it: it's materials, associated textures and modifiers.
When linking an object you can then make it a proxy in your current scene, this allows you to override some of it's properties like position or materials. You can also make the object local, which allows moving it in the scene.
Linking a group instance will bring in a static group of objects, as if they were a single object.
For more complex interactions you can link objects and armatures to rig it locally and animate it, although I am not an animator myself, so am not at all comfortable in this area.


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How to render Compositing only by OpenGL?
I do not use any object in my scene. All my Nodes are in the compositor, but when I render compositing by OpenGL I get only an empty screen.
I can use objects as simple trick, but I don't like that. I need output my compositing by opengl directly.
How can I render compositing by OpenGL only in blender?
- Using file node will use Blender Engine not Opengl
- When I press F12(Internal Blender engine) I see my compositing result.
- When I press Camera button(rendering by opengl ), I see nothing...empty viewport

OpenGL render active viewport operator will render, shockingly, what is present in viewport. Compositing nodes aren't taken into account. This may be used for quick test renders of objects present in scene. It seems you don't differ Preview render and Final render, see more on that - http://blender.stackexchange.com/questions/2728/what-are-the-technical-differences-between-f12-render-and-viewport-preview.

Related: http://www.blendernation.com/2016/04/03/take-control-opengl-renders-advanced-boomsmash/

That just not possible. OpenGL rendering only "saves" the current viewport content as an image. But when the only content created is in the Node Composit, that won't serve as a valid viewport content. Though there is a File Output Node for your Node Tree that you might use instead.


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Boolean modifier not working with hiccup
Newbie to blender here, I've done quite a bit of searching through the rest of the forum for this answer but I'm sorry if it's already been asked.
I work in a medical office and we might possibly be 3d printing a prosthetic nose attachment.  We have a patient missing some of her nose and I have a 3d scan of her face.  I also have a 3d scan of someone else's nose I am trying to fit on the front of her face. (Pictured, I can't show much more for confidentiality reasons)

I've lined them up fairly well and I was thinking I'd use boolean difference to "carve" out from the nose attachment everything that was really on the patient's face.  For some reason the modifier just isn't working at all.  When I click, nothing happens.  I've read around the forum's and suggestions such as solidifying the objects (they already have been) don't seem to work.  The bulk of the other suggestions deal with making sure the objects are manifold.  When I use shift-ctrl-alt-m to find non-manifold surfaces, nothing shows up.
The other thing I read was that overlapping parts can cause some issues for the boolean modifier... well, that one I don't know how to get around.  Maybe you have some suggestions?
Edit:
Update for you:  both items are scaled the same.  I removed all doubles, followed guidelines suggested by cegaton and made sure normals faced the same way.
They had been solidified but I noticed that the modifier WAS actually doing something, it was just drawing a faint line around the nose where it overlapped.. so I realized while the face was solid it just wasn't very thick.  So I solidified it as much as blender would allow me (without turning the face into a giant ball) and tried again... Which resulted in this:

My overlap threshold is set at 0.0002.  That seemed to make it more noticable than when it was set at 0.000001.... but let me know if thats a huge mistake.
Or if there is an easy way to separate the part of the nose I want after it did draw a faint line.... I'm game.

Your meshes may also be too complex, try reducing them to the smallest most essential parts only before the operation

Booleans are odd things and need certain things to be right before they work, one of the things that stops them working is Scale.
Make sure you have the scale of both objects set to $1,1,1$. by pressing Ctrl + A to Apply Scale (adjust geometry to match the scaled version and set scale to $1$.
Also try and make sure your models are fully closed (solid with no holes). Since  your working with  a scan of a face, try to add geometry on the back, or use the Solidify modifier with a large thickness, to turn it into a solid object.
I also find the Bool Tools addon helps me a lot as well.
Occasionally I have also used a work around of copying the Boolean objects and pasting them into a fresh scene and voila, it works! Not always a reason given, you can then paste them back to where they need to be.

Literally no idea why it finally worked, but bool tools did it. Carve boolean solver instead of bmesh.


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Mesh became grey when I recalculated normals, can't fix it
So I was cleaning up an object in blender (mold I'm making of an eyelid to 3d print and pour silicone into) and things started going haywire.  I filled a hole in some faces and the new face became purple (In solid mode, whether in object/edit mode) and I read online that could be because the faces didn't align properly.  So anyhow I selected everything and recalculated normals, and now my mesh is dark grey (Pictured)

I read that dark grey faces could be directly because of the normals (make sense) but I can't fix it!  I'll recalculate them, look at them in face orientation mode, etc..   and they're still dark grey.  Help!
Blend file if you're interested:

Isnt that because of material setup? (viewport color, second material slot) Please attach your blend via https://blend-exchange.giantcowfilms.com

I had read that on other answers on here (that it could be because of material setup) but neither object in here has materials, and one isn't dark grey.  I just tried to attach the blend on that link, THINK its processing at the moment?

It's not processing... it's waiting for you to press "upload"

@ChristopherBennett it is processing after you hit upload. JoeCrozier - try it again ...

@vklidu Its uploaded now, was giving me heck last night

Check Custom Normals

Search for "Reset Vectors" operator

@vklidu  The reset vectors did it!  Do you want to "answer" it so I can accept that answer?  P.s. what the heck is that?

Thank you, happy to hear you solve it,. Your Q is quite common, so I guess it would be closed as duplicate anyway. I was lazy to search for similar, it is not always easy to find it here. If you want to answer you are welcome :) Also you can flag the comment so others can see it was helpful.

Per @vklidu's comments, the "reset vectors" operator did it, not sure why.

Go into your objects Data tab and click "Clear Custom Split Normals Data"
This should help it look correct within Blender.

XRAY Top right side of the screen.  That's what worked for me.

Hi, thanks for the post. This site is not a regular forum, answers should be substantial and thoroughly explain the solution and required workflow. One liners and short tips rarely make for a good answer. If you can [edit] your post and provide some more details about the procedure and why it works feel free to restore it, otherwise it may be deleted or converted into a comment. Perhaps add a few images illustrating the workflow and final results. See How do I write a good answer?


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Weird wavy lines
I'm sorry I can't really provide a ton more info for this question besides just screenshots, because I wouldn't even know where to begin but:  anybody know why I'm getting these weird horizontal lines?:

They are not visible in the solid view:

And I only have a basic lighting setup and scene (3 area lights, nothing in between the lights and this object, simple plane in background.  Blender 2.9, and just a basic scene I dropped the objects into.  The material is just a very basic material I made by saying add material and then setting the color.  No nodes or textures or anything.
These two questions seem to be the same problem:  strange black lines on object when rendered
Why do these weird lines appear in my render?
But none of the solutions offered seem to fix it (setting the origin point or scaling)

It looks like duplicated or overlapping faces, causing z-fighting

I can't seem to find any duplicated or overlapping faces, though i won't say that couldn't be the cause.  Just nothing apparent when i go inspect closely in edit mode or anything

Could this be related? https://blender.stackexchange.com/questions/130689/strange-black-lines-on-object-when-rendered/130697#130697

Edit:  I said the solutions from the other questions didn't work but one of them KINDA did.  Applying a scale to my lights didn't necessarily do anything, but when i radically increased the size of the lights it did fix it.  From 0.1m to 10m   (the whole object is huge at the moment).   So maybe it was some sort of mismatch between light size and what it is lighting up?

I think the reason that they are there is because they are in the shadows and the image is very noisy. If you up the sample rate it should get rid of the lines. Could you link the blend file?

Unfortunately I can't link to it as the bones are real live patient data (and names of objects and stuff include PHI, would be a pain to get rid of).  As I said in one of my comments, increasing size of the light seemed to fix it.


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blf + bgl text flickering
I'm using blf in a modal operator to draw help text on the 3D viewport. Here's a snippet:
FONT_ID = 0
bgl.glColor4f(1.0, 1.0, 1.0, 1.0)
try:
    blf.position(FONT_ID, x, y, 0)
    blf.draw(FONT_ID, line)
finally:
    bgl.glColor4f(0.0, 0.0, 0.0, 1.0)

This works well, but when the user moves the mouse, the text flickers: when the mouse is moving it's a bit bigger, and when it stops it goes smaller. When it's bigger it also appears a little blurry. I think the texture that the text is being painted onto is being scaled incorrectly when the mouse moves. I've checked the parameters that I'm passing to blf.draw and blf.position, and they're not changing.
Is there any way I can stop this from happening?

Oops, I should have been setting the font size.
blf.size(FONT_ID, 14, 72)

My guess is that some other text code is not resetting the font size properly. Similarly, when using text shadow, you have to set the blf.shadow_offset (even if you want to leave it at 0, 0) to avoid the shadow flickering.


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degrouping stl file objects on blender
I have imported an stl file to blender and its separate objects I can`t figure  out how to deselect the objects.
I have tried all the selection and deselection option
s
The file was made on 123D
this is the STL file I imported to blender and I want to un-group the highlighted objects any suggestion thanks?

What is your question about ? Please elaborate on "degrouping objects" and "separate objects"; also provide some screenshots of the problem, what tools you have already used and why they didn't work. Thanks.

Check the update to the question

Does this answer your question? http://blender.stackexchange.com/questions/6184/splitting-pieces-of-a-mesh-into-a-new-object

Use the Separate function.
Enter Edit Mode (Tab)
Highlight (select) the object you are breaking apart, press space, type "separate" (or use the keyboard shortcut P) then pick "Loose Parts" from the list of options.

To help you select the parts, you can select one vertex of or the specific item you want to separtate and press CtrlL to select all of the connected vertices. Then separate using P
A different way to select different parts is using Box select (CtrlB


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Blender 2.77 Bsurfaces add-on works with "d" key in Mac version but not on PC version
I've tried out Blender 2.77 on my MacBookPro 13" screen and all works as expected. I moved on to my Asus laptop with 15" screen (with a better video display) and installed 2.77 also with the Bsurface add-on.
When holding down the D key to draw with the mouse, nothing is drawn.
Do you have any suggestions? I'm relative new to Blender. Thanks
I've done further testing and here's the issue:  One of my PC computers doesn't change the curser to a brush icon when holding down the "d" key.  (works fine on another PC - desktop instead of laptop, same manufacture: Asus.)
When I remote into the Mac where Blender functions as expected, drawing is still not working, yet when I remote into the PC from the Mac, the drawing works as the curser changes to a brush.  I've contacted the PC manufacturer but they claim it's a software issue but they have offered to have the PC reimaged, something I already did and I have the same issue.
This undocumented feature is unique because drawing works when I use the GreasePencil draw button, but doesn't work when holding "d", and only on this PC laptop, works fine on 2 PC desktops and Mac laptop, one uses Windows 10 as the laptop that has this issue, the other Windows 7.  I've tried different versions of Blender still same issue.  It would be nice to have a solution or even a workaround because currently this is just an inconvenience in having to take the extra steps to draw lines in Blender.
Anyone else with a suggestion would be appreciated.

The D key enables drawing with Grease Pencil. Bsurface has nothing to do with that if nothing is drawn. Make sure there's GP layer assigned to the object; also enable it with Draw button in the Toolshelf > Grease Pencil to check you indeed started drawing.

Mr Zak, thank you for your info.  I've checked the settings several times again to make sure that drawn lines are set to link to the object instead of scene in both the GreasePencil Toolshelf shelf and the menu for creating a new GreasePencil entry plus created a new layer to confirm detail settings but I still have the same issue.  I've added more information describing my further tests to get this resolved, to my original post.

Did you try actually drawing with GP on the problem laptop ? It could be that cursor isn't changing to brush but still the tool can work. Anyway this reminds a bug; check that D button really works on that computer, try setting on another shortcut in user prefs. I'd suggest using Continous Drawing option of GP but if drawing for Bsurface then it's not solution.

GP works fine on the GP menu using Draw, the only thing that doesn't work is using the D key on the problem laptop.  I can draw using the D key when I remote into the problem laptop from my MacBookPro.  If I change that around then the drawing with D key doesn't work from problem laptop to MacBook.  The D key does work in other programs with problem laptop.  This doesn't appear to be a software issue per my test in exchanging the input via the remote access of the PC and Mac computer, yet how could it be a hardware issue if the PC works with every other program.

I found a work around for the issue with the NX500 Zenbook from Asus not working properly with Blender when using the "d" key to draw with the touch pad.  It works by just using the touch screen.