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Import DXF and make it fit work area
I feel like I've fallen at the first hurdle, importing a DXF file.
By that I mean, I figured out how to enable the dxf import tool, and imported the file I had, but that's about it.
I'm struggling how to manage the workspace and actually view the file I've imported or do anything with it. Maybe I'm doing the import process wrong? Do I import it as a new scene, do I center geometry, etc, etc?
When I selected center geometry I could at least see something, but it looked like my imported file is maybe way to big for the workspace, as all I could see when I zoomed right out, was the first letter or so of some text from the imported file. (see screen shot).

Ok, I went the other way as you pointed out. Used 0.01, which brought a lot more into view, but still very large, so... used 0.001 which brought more into view, but it doesn't look anything like the plans I see in Autodesk?

To give you an idea of what it should be looking like, this is it in autocad. View from each side, floor plan for ground and 1st floor... two view of the entire building plot, one showing topography and a street view elevation.

Two more Blender screen grabs: this is imported at 0.0001. The first image is relatively close up to the workspace grid, and then second is zoomed out. The closer view looks like I'm getting close to the size I need. In the zoomed out view... I've no idea what is forming the large circular patterns as I can't see anything like that in the original drawings???
Would it help my progress if I removed some of the layers from the original file? I obviously don't need things like drains and internal wood framing, water mains, wiring, etc.

As you can see from the last screen grab... I've kinda got the plans into the work area, but I don't know what is affecting the view. What is causing this grey shading across the work area?
There was more of it, in ever increasing circles going out from the center, but I removed some by hiding certain layers, but can't seem to view just the plans without this shading?

Does it work to hit [A] (toggle select all) and [S] (scale) and scale it in?

Check scale, center geometry to origin, shift+C, clipping planes...
When importing DXF there are a few options to work with.

One is the scale. The default settings is scale = 1, wich obiuvsly means that Blender will multiply by this factor the incoming units of the DXF.
So if you had drawn with your vectorial software a square of 2mx2m, blender will import an object of 2unitsx2units.
If you were working in cm, your square shall measure 200. If in blender you are going to work in meters, you must put a 0.01 factor...
This is valid also for the location of objects. So it is important to consider also the relative distance of the square from the origin of the sistem. To avoid problems, if Is possible, I would suggest to move the geometry to the origin in your drawing software.
Another tool that may come useful is Shift+C

It will extend your view till all visible objects are in the 3d view. If it seem that the camera de-zoom too far away, there are probably objects much distant from the origin. Notice that they might come outside of the 3D camera's clipping planes, making them invisible.

Thanks for the replies.
OK, when doing the import, I set the unit scale to -10.0, and that revealed some more of the text from the plans, but obviously from the screen shot below... it's still huge.
Do I just keep going down in scale on the import until it all comes into view?
Incidentally, I didn't create the plans. They were created by an architect and (after some resistance) they provided the dwg files for me to try and create a 3D render.

If you don't know the units in which the file was drawn, you'll have to try different values till you guess right. Notice that scale factor is  meant to be a multiplier, so if comes out too big, next time try a smaller value. Don't use negative values, they flip geometry.

Hi Carlo,
Thanks for your help so far.
I used an import scale of 0.0005, which put all the plans within the grid area. But, if you check the new pics in my original post... there's still something not right. Not sure which element is producing the grey sketchy background and preventing me from seeing the plans properly to work with.
The original file included everything needed for construction, so... do I need to strip away all that I don't need for an external render and save a dxf file with just the minimal data needed?
Any further assistance would be hugely appreciated.
Thanks,
Del.

Maybe is better to continue in a chat room so I can ask you some things.. Would you join me there (http://chat.stackexchange.com/rooms/26021/import-dxf-and-make-it-fit-work-area)?

Ah... because I'm new to this forum, it won't let me use the chat room.

I can see what you're writing, but can't respond. :(

Eh, you're right.. mumble, what we can do...

OK, we'll write here and than we'll delete all if needed...

What happens if you "Zoom to extent" (double click on the scrool wheel button) in AutoCAD? Is the scene wide or small?

To be honest, I'm still not sure why architectural plans in cad format are restricted by the architect.  could understand if it was a groundbreaking design, but... just for a regular house???
Personally... they haven't specifically said I can't share them, just that they were only to be used to produce a 3D render for the property owner's website, so... I would consider this part of the process.

Anyway... in CAD, if I double click on the scroll wheel, it fits the plans to the visible area of the screen.

No, don't do it if you are not sure. A thief might use them to obtain info...

Ok, and everything is ok in that view? Nothing strange? just plans?

I've added a screen grab of what I see in CAD when I double click on mouse wheel.

Now, select all you se, and COPY them in the origin of a new file. In this way we'll get rid of the hidden objects..

Next step could be explode all the object in AutoCAD. A large number of autocad primitives (ellipses above all) are not correctly handled by the DXF importer, so by exploding we'll simplify a bit the geometry...blocks, text, polylines..shall all becomes lines.

Well... I'm not sure I've done that right. I tried to copy all that was visible and put in a new document, then save as dxf and import in Blender, but still... new screen grab I've added shows there's a lot of data that seems to originate from way outside of the plans as they display in CAD.
Sorry... I'm new to CAD, too. I've always been very quick to pick up new software and instinctively find my way around, but this stuff... it's scrambling my brain. LOL.

Is it impossible to delete those big objects? Maybe we'll lose some geometry, but at least we'll se the plans

Gimme a moment, let me see.
I did try deleting some layers, but it wouldn't let me.

Just thought... might help to show you what's been imported. See latest pic.

That's OK, these should be the layers that once in blender are considered as groups..

That's what is in Blender. If I hide some layers, it removes some of those large grey areas from the screen, but... I can't seem to remove all the large grey areas.

Try to Select all by pressing A, than Alt + C to convert everithing to a mesh, than "set origin to geometry" ...now you should be able to select the bigger object so we can see what is behind and if there are other problems in addition to the circles

OK, I did that, but couldn't discern any significant change. What I did do, was hide more layers and the layer labelled 'buildings' once hidden, seemed to remove the remaining grey background area, which seemed counter intuitive.
So... I can see more of the plans now, but despite using the same import scale I had earlier... it doesn't all fit within that work area grid.

Those dotted lines means that you have some parented objects. Delete hierarcy by select all with "A" and Alt+P ->clear parent and keep trasformations

OK... did that. It removed the dotted lines.

If I zoom out, there's still a lot of stuff that seems almost disconnected from the main body of the plans.
But... am I almost at the point where I can reduce the focus of the plans to the work area, and maybe start putting them together into 3D configuration?

Actually Carlo... you're in Italy, I'm in the UK... it's late by both our clocks, so... just leave it there. As and when you get a moment at a more reasonable hour, if there's anything you can add to help me get on the way to my first 3D render... I'd be very grateful.
Until then.... thank you very, very much for taking the time to help me out so far. I really do appreciate it.
Del.

If you can easly select the "correct objects" you can invert selection and delete the others

Yeah! See you soon...

I'll experiment with hiding/showing layers to see if I can identify the stuff I need, and the stuff I don't.
I'll post screen grabs with the results so that you can see how far I've got when you check in again.

Added one final screen grab for where I'm at.
Now I'm going to go sleep, before my head explodes. :)

Hi Carlo. Been doing some reading this morning and have been wondering... have I exported the dwg files as the best version of dxf for Blender to work with?
By default I selected to export the files as 'AutoCAD 2013 DXF' but... there's 4 or 5 other options, ranging from AutoCAD 2000 to 2010. There's also a version called R12/LT2 DXF. So... should I be generating a different version of the dxf file for better results?
Also, from what I've read... is it better if I have each element of the plans in a separate file? One for each floor, one for each side, etc?

Hi! I think that 2013 DXF is the best option you have. Yes, cerntely separing each plans would help. Try also to run the command "purge" in autocad to clean up the file a bit. The main problem is that the cfircle and ellipse primitive are not handled correctly, so the are overscaled and in the wrong location. As they are imported as 2D curves they create those grey plans.

OK, never used the Purge command before... see the new screen grab I added to my post... is there anything I should, or shouldn't check or tick on that command window?

I decided to tick all the boxes and purge all, saved a new dxf file and imported it into Blender... still all the elements linked outside of the main plan.
I had no idea it was going to be this difficult just to get some plans imported. Previous videos I'd watched seemed to look a lot easier. :(

Ehh, it dependends of how it's your file made, but usually what you see will not be deleted. So purge all...

If you encounte so many difficulties, maybe you can: -import dwg to 3dsMax and then export in OBJ -use a different format (ex:FBX) - print the layouts out with a dwg to pdf than import pdf in Inkscape and save as SVG

The plans were originally suppl;ied to me in pdf format, but |I asked for the dwg files as I assumed they would be better for importing into 3D modelling software.

If you don't need to be precise you can even import the layouts as backgrond images to use as references...it depends on what is your purpose. DXF preserve the max amount of information (layers, splines, beziers...) but if there are problems and you don't need such precision, maybe a more simple file-exange forma is better suited

OK, perhaps I should have explained my end goal... I would like to produce an external render of the property in the plans. No internal details, just a conceptual view of how the property would look when complete.
So obviously, plans that include drainage, water mains, manhole locations, etc... I don't need.

OK, now I'm courios, so if you trust me, I'll send you a link to a temporary mail where you can send me the dwg so I could tell you what's wrong with it. Once we've solved the problem Iìll destroy all the evidences

Do you use Skype, Carlo?

importing DXF can speed up a lot with the modeling Yes I use it. Not very often... I'm not sure if I'll be able to remenber tha login

I'll contact you on skype...gimme 10 minutes

I should have sent you the invite

Accepted your Skype request.


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Can I save presets for the inset tool?
I am currently working on a model where I find myself making 4 different repeated insets with different depths and thicknesses for bolt head recesses.
The inset tool remembers the previous used setting. Is there a way to load and save a preset for it, and save me typing it in each time and reduce the number of post it notes stuck to my monitor?
If the answer is no could someone indicate if this is the sort of automation script suitable for a relative newcomer to scripting? I'm tempted but a little wary to give it a go.

No there is no way save for scripting to load and save presets for operators that do not explicitly support it in the toolbar. This would not be my recommendation for a first project in blender API however after a few basic tutorials (maybe this ) you should be able to do this sort of thing on your own.
Edit: Another alternative that comes to my mind is duplication. I can't tell if that is helpful but certainly making one bolt by hand is far easier than making a script to do it.

source: Stack Exchange

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

sort: votes


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How to make a rope in the BGE?
I'm pretty sure this has been asked before, but for the life-o'-me I couldn't find it.
How would one setup the physics for rope in Blender Game Engine?

I tried soft-body; didn't work
Incremented/decremented the properties in different ways; didn't work
tried writing my own; fell on it's face

So how would I make a long object move like a rope. I was planning on using it for 'dreadlocks' like the wookies from Battlefront-2 so it needs to be able to sustain being moved constantly by animations.
other uses include

rope (dur)
vines
ziplines

Thanks!

I have no game engine experience.. but any chance it's related to this one? http://blender.stackexchange.com/q/15809/822

@ajwood not quite. if you switch your render setting to blender game you will see that the physics tab is much changed. Also no constraints work in realtime.

Does the Hook modifier work in BGE? Or something similar? Because you could just hook the ends of a softbody, or hook links of a chain/rope together.

The are two main ways to make a rope in the BGE. Soft bodies, and ridged body constraints.
The ridged body constraint method.
This is the method Phymec uses in videos like this. I have not gotten good results with soft bodies, so I will focus on the ridged body constraint method.
This is very easy to set up, just add a sphere, model it in to a capsule and add a Rigid Body Joint constraint.

Then string many of the capsules in to a rope, with the next always having the target of the one before it. Set the Pivot to be in the middle of the two capsules (turn on Display Pivot to see where the pivot point is).  Also important turn on Linked Collision; if not on the rope will try to break apart where ever it is intersecting.

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


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How to change dimensions of an object proportionally?
I need to change the 3 dimensions of an object, but only by changing one dimension.
That is, if the object has the following dimensions:

height: 2 units (Z)
width: 0.5 units (Y)
depth: 0.1 units (X)

When I change the height of 2 units to 3 units, then the other width dimensions (Y) and depth (X) should automatically change to 0.75 and 0.15 respectively.
I do this by scaling (S):

I press the S key
I press the = key
After Income Division 3/2. 3 is the new dimension and 2 above.

But I would like to know if there is a better way to do so through the properties panel (N).
The options in the properties panel, when I change the height of 2 units to 3 units, the width and depth do not change.

For now I think your current approach is the best way of doing this. This should be possible with multi number button editing in the future, but there is currently a bug preventing this.


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Move the tool shelf panel to the other side?
I somehow managed to flip the T Tool Shelf panel from the left side of the 3D viewport to the right side so it sits next to the N Properties panel.
How did I manage to do this and how do I move it back?

Move the mouse over the Tool Shelf and press F5. This can also be done with the Properties sidebar and headers.

Cool, that works most most everything!

I did this once and thought it was a bug :P +1!

I wanted to ask the same question but fortunally the answer is already here. Thanks a lot!

Hi there, is there any way to accomplish this through other means? Hovering and pressing F5 on my Mac isn't working (it may have to do with the fact that I need to press Fn and then F5, because Mac makes F5 turn down the keyboard brightness). Thank you!

Found the answer here (hover and search for Flip Region): https://blender.stackexchange.com/a/154767/15400

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Stripe along center of mirrored model?
I have a stripe down the center of my model and I'm not sure why. I used mirror mod to create the vehicle and have tried reseting 3D cursor and moving the mesh in and out.

Here is the .Blend file

Could you post your .blend

Be more specific; explain what you want better.


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Mesh not UV unwrapping well?
I have my model made and seams marked but the mesh doesn't unpack well. I tried exporting and painting it in Photoshop anyway but doesn't apply like it should. What am I doing wrong?
Solid view:

Textured View:

Rendered View:

Seams/Wireframe View:

It looks like your normals are messed up. Try selecting the entire mesh in edit mode and pressing Ctrl N.

Thanks, everything looks like it should. Any clue why I would be missing vertices after import into Unity?

Did that fixed it (I wasn't sure what you meant in your comment)? As for exporting to unity, that sounds like a separate question (and should be asked as such) :)

all issues fixed

It looks like the normals are not consistent.
Those dark spots on the mesh are caused by flipped normals. By enabling face normals display in 3D view > Properties region > Mesh display > Normals, you will notice that they are pointing the wrong direction:

To fix this, select everything in edit mode (A) and press CtrlN.
Now all the normals should be facing outwards:

I flipped the Normals but it's still odd. Here is what it looks like.
[link]https://drive.google.com/file/d/0Byz8DRhnzr0RR2tPaGJjRHJBYzg/edit?usp=sharing[link]

@Jonny314 ??? I'm confused.. What does that have to do with this?

@ Gandalf3: Jonny314 just seems to be unfamiliar with this sites format.

@Jonny314: Normally around here it's customary to start a new question for each distinct category of issue.  It would make searching this site very difficult if random topics were all mixed together on every thread.  People would have to dig through piles of unrelated info just to find what they are looking for.  Feel free to bring up the new problem as a separate question.  This way things here will stay more focused and organized.


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Meshes joined in Blender are still un-joined in Nifscope
I created a posing character as static meshes from a body with a skeletion. It shows up fine in Oblivion. I want to join all the meshes that make up the body (upper, lower, etc)  so i can quickly paste this newly created single mesh into another .nif, or otherwise manipulate it. The meshes were  joined in Blender with CtrlJ.
It seems to have exported with no problems, since it shows up in game with no problems.  However, the meshes are still shown as separate pieces in nifscope, so I have to copy and paste each piece to move it. So evidently, importing to Blender, joining the meshes, then exporting is not the solution.
Nifscope 1.1.3 rev 36bfdd/
Blender 2.49b

what is the reason you are using 2.49? blender is up to 2.75.

Games are sometimes more compatible with specific Blender builds. I use TES Oblivion engine.

Note that such old builds are not as readily supported, and bugs will most likely not be fixed.


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Color Issue when texturing a surface

Brand new blender user with no experience, trying to map a texture to a single side of a cube for an animation. I am having an issue where the black areas of the image end up looking white when applied to the object. The preview of the texture looks correct, but the material preview, as well as the actual render do not.
I have tried messing with all the settings, but no luck. What am I doing wrong?

Could you show some screenshots?

I have one picture up, I realize it might not be helpful. What do you need to see?

Oh, just didn't see, is your texture displayed properly in Texture view?

yes, the texture view is correct. You can see that it is supposed to be a person wearing a black shirt against a dark background, but all of this appears white in the 3d view

Can you show how it looks in render view

I added a picture of the render to the post.

Try to go to Node Editor and in between Diffuse and Material Output node plug Invert Node

I tried this, but I'm not sure if I am understanding correctly. image

could you upload your blendfile with the picture?

There was an image in my previous comment. Is that it or are you referring to something else?

Misread the comment, here is my blend file. file

I'm still not sure what the issue is, but I deleted the material and created a new one and added the texture again and it seems to be working now. If anyone has any insight it is still appreciated, I am trying to learn.


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Artifacts when using boolean modifier (difference) on simple mesh
I am rather new to Blender so most likely my problem has a simple solution but despite by online search I could not find any similar example.
I have quite a simple mesh and I am trying to cut some holes from that mesh. I want to use modifiers as they simplify changes that I might have to make regarding cuts.

So the first boolean is similar to making the inset and removing it. At that stage everything looks pretty OK.

The object that is used for boolean operation looks very similar to first one.

Real problems starts when I want to add second ad third cut. In both cases (second and third cut) the object used for boolean operation are identical - a simple cubes.

The final result depends on the positioning of those two cubes. In some cases there are no artifacts in some cases they are pretty visible.

All object has Shade Flat and all objects has Normals outwards.

It would be useful to have a look at your .blend file, but I would recommend adding the three objects you are using as boolean objects into a single mesh:

In object mode, select all 3 boolean objects using Shift+Left-click
Use CTRL+J to join the meshes into a single object.

You should then be able to use this single object and a single boolean modifier to make your cuts. This may help to resolve your issue, thought it's difficult to say for certain without taking a look at the file.
Also, Blender sometimes struggles to handle overlapping normals, and it looks like the normals of some of your boolean objects are overlapping.
You could maybe try moving the the faces on your two cube-shaped boolean objects so they do not overlap with the centre boolean object.

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


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Specific UV maps for each instance in For Each Element
I have created the goemetry node setup that creates a grid with dimensions that are based on the size of instance and the between-instance space. Then using a For Each Element node I am assigning a uv map on two selected faces of each instance. My problem is that each instance should have its specific offset in terms of uv map coordinates because the entire idea is to assign only portion of material to each instance so all of them are making entire image.
My setup calculates also the offset (now only for X axis but the Y axis is the same story) for each individual instance but I do not know how to add that element to calculation of the uv map coordinates.
So lets start from beginning. Below is the top level setup that creates grid, instance mesh on pointsm calculates proper offset for each instance and then creates uv maps for each instance. However the uv map fora each instance is the same.

As you can see on the picture below the vm map is assigned to each instance but it is the same uv map. The tile that is displayed depends on the value of X Position and Y Position.

As I written above I am able to calculate proper offset of each of instance (for debuging purposes it is stored as variable TEST).

All the calculations of uv map coordinate take place in group node called UV Map to Face and the setup of that node is shown below.

I should somehow inject values specific to each individual instance somewhere between Vector Rotate node and Store Named Attribute node but I do not now how. I tried to use TEST attribute (that is stored outside this group) but it did not work. I have modified the setup that calculates the uv map coordinates in the way shown below

But it did not work and the effect of change in terms of final result is lite this

SO the question is how to ensure that calculation of vm map is using values specific for each instance.

Ideally, you keep instancing and store UV offset as additional attribute used in the shader:

Imgur mirror (SE image hosting has problems)

Imgur mirror

Imgur mirror
If you really need to modify the UV map of the instances, bad news: UV maps are mesh data, and instances share mesh data (that's the whole idea behind instancing, reusing data), so you can't do it. Now, you can realize instances, making it a single big mesh, recalculate UV map the way I do above in the shader, but do it in geonodes, and then you can split this mesh into instances. The important thing here is: you would throw out the window the advantage of instances, because now each instance points to unique data, so instances, instead of reusing data, are just adding an additional overhead. It's like having 9 cars all compliant with 1 standard, but then you want each car to have a different color, but the standard doesn't allow this, so you create 9 separate standards, each for one car. Of course it would still make sense if you e.g. wanted to duplicate these 9-color cars into 10 groups (totaling 90 cars), then each standard would be used 10 times...

(1/2) Markus. I have a bit of programming experience so I figured out the idea to have a single object (something like class) that stores some common data (like shape, size, beveling and so on and so forth) but then when the object (class in programming) is instantiated some attributes if the instance can be overrided. Having in mind that every instance of (created from single) mesh can have its own position, rotation, scale and even color I though that also UV map modified so it is specific to each instance because in fact it is quite logical.

(2/2) It is a pity it does not work like this. Correct me if I am wrong but in order to apply separate UV maps to different instances I have to convert them first into mesh. However - I am asking because I am quite a beginner with Blender - can I convert the instances into separate meshes so each instance is a seperate mesh and do it all in geometry nodes or conversion of instances into mesh creates one big mesh.

@JanPips The thing with each mesh having its own position is that it's not the mesh vertices having their own positions, only the base location of each instance has its own position. The vertices inside the instances all have the exact same data, the relative offset from their base location. And as Markus said, since UV maps are mesh data, they are all the same across the instances.


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Determine which button was pressed from python
Prompted by my previous question, I was trying to create an addon to move background images with the mouse.
However, I can't figure out a good way to determine what image to move.
I thought I might somehow add a button to each background image panel in 3D view > Properties region, but is there a way to get which image's button was pressed?
Here is a modal operator (based on the template) that picks an image based on a bunch of hacks that fail in too many situations:
import bpy, math
from bpy.props import IntProperty, FloatProperty

class MoveBackgroundImage(bpy.types.Operator):
    """Move background images with the mouse"""
    bl_idname = "view3d.background_image_move"
    bl_label = "Move backgound image"

    first_mouse_x = IntProperty()
    first_mouse_y = IntProperty()
    first_x = FloatProperty()
    first_y = FloatProperty()

    def modal(self, context, event):
        if event.type == 'MOUSEMOVE':
            delta_x = self.first_mouse_x - event.mouse_x
            delta_y = self.first_mouse_y - event.mouse_y
            if event.shift:
                backimage.offset_x = self.first_x - delta_x * 0.01
                backimage.offset_y = self.first_y - delta_y * 0.01
            else:
                backimage.offset_x = self.first_x - delta_x * 0.05
                backimage.offset_y = self.first_y - delta_y * 0.05
#                backimage.size = self.first_y - delta_y * 0.05

        elif event.type == 'LEFTMOUSE':
            return {'FINISHED'}

        elif event.type in {'RIGHTMOUSE', 'ESC'}:
            backimage.offset_x = self.first_x
            backimage.offset_y = self.first_y
            return {'CANCELLED'}

        return {'RUNNING_MODAL'}

    def invoke(self, context, event):
        go_hack = 0
        def get_view_orientation(view_matrix):
            r = lambda x: round(x, 2)
            view_rot = view_matrix.to_euler()

            orientation_dict = {(0.0, 0.0, 0.0) : 'TOP',
                                (r(math.pi), 0.0, 0.0) : 'BOTTOM',
                                (r(-math.pi/2), 0.0, 0.0) : 'FRONT',
                                (r(math.pi/2), 0.0, r(-math.pi)) : 'BACK',
                                (r(-math.pi/2), r(math.pi/2), 0.0) : 'LEFT',
                                (r(-math.pi/2), r(-math.pi/2), 0.0) : 'RIGHT'}
            return orientation_dict.get(tuple(map(r, view_rot)), 'UNDEFINED')
        for area in bpy.context.screen.areas:
            if area.type == 'VIEW_3D':
                for space in area.spaces:
                    if space.type == 'VIEW_3D':
                        vmatrix = space.region_3d.view_matrix
                        view_orientation = get_view_orientation(vmatrix)
                        view_persp = space.region_3d.view_perspective
                        global backimage
                        for bgimage in space.background_images:
                            fail_hack = 1
                            bgi_axis = bgimage.view_axis
                            expanded = bgimage.show_expanded
                            if view_persp == 'ORTHO':
                                go_hack = 1
                            if view_persp == 'CAMERA':
                                go_hack = 1
                            if go_hack == 1:
                                if expanded: #HACK
                                    if view_orientation != 'UNDEFINED':
                                        if view_orientation == bgi_axis:
                                            fail_hack = 0
                                            backimage = bgimage
                                            self.first_mouse_x = event.mouse_x
                                            self.first_mouse_y = event.mouse_y
                                            self.first_x = backimage.offset_x
                                            self.first_y = backimage.offset_y

                                            context.window_manager.modal_handler_add(self)
                                            return {'RUNNING_MODAL'}
                                        else:
                                            fail_hack = 1
                                            fail_message = "No active image, could not finish"
                                    else:
                                        if view_persp == 'CAMERA':
                                            if bgi_axis == 'CAMERA':
                                                fail_hack = 0
                                                backimage = bgimage
                                                self.first_mouse_x = event.mouse_x
                                                self.first_mouse_y = event.mouse_y
                                                self.first_x = backimage.offset_x
                                                self.first_y = backimage.offset_y
                                                context.window_manager.modal_handler_add(self)
                                                return {'RUNNING_MODAL'}
                                            else:
                                                fail_hack = 1
                                                fail_message = "No images visible in camera view"
                                            if bgi_axis == 'ALL':
                                                fail_hack = 0
                                                backimage = bgimage
                                                self.first_mouse_x = event.mouse_x
                                                self.first_mouse_y = event.mouse_y
                                                self.first_x = backimage.offset_x
                                                self.first_y = backimage.offset_y
                                                context.window_manager.modal_handler_add(self)
                                                return {'RUNNING_MODAL'}
                                            else:
                                                fail_hack = 1
                                                fail_message = "No images visible in camera view"
                                        else:
                                            fail_hack = 1
                                            fail_message = "View not aligned to an axis, no images visible"
                                else:
                                    fail_hack = 1
                                    fail_message = "No active image, could not finish"
                            else:
                                fail_hack = 1
                                fail_message = "View not in ortho or camera perspective"
                        if fail_hack == 1:
                            self.report({'WARNING'}, fail_message)
                            return {'CANCELLED'}
def register():
    bpy.utils.register_class(MoveBackgroundImage)

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

if __name__ == "__main__":
    register()

    # test call
    bpy.ops.view3d.background_image_move('INVOKE_DEFAULT')

Looking at space_view3d.py, I suggest you add a button for each background image and pass the index to your operator.
    def draw(self, context):
        layout = self.layout

        view = context.space_data

        col = layout.column()
        col.operator("view3d.background_image_add", text="Add Image")

        for i, bg in enumerate(view.background_images):
            # ...
            box.operator("view3d.background_image_move").index = i
            # ...

In your operator:
class MoveBackgroundImage(bpy.types.Operator):
    """Move background images with the mouse"""
    bl_idname = "view3d.background_image_move"
    bl_label = "Move backgound image"

    index = bpy.props.IntProperty(name="Background image index", default=-1)

    # ...

    def invoke(self, context, event):

        #...
        if self.index < 0:
            print("No valid background image index given")
            return {'CANCELLED'}

        try:
            backimage = space.background_images[self.index]
        except IndexError:
            print("No background image with index %i" % self.index)
            return {'CANCELLED'}

        # use backimage below

The index number used for the operator button in the space_view3d.py panel will always be up to date, since it is in the draw() function, which is called whenever a background image is added or removed.
The additional checks for the index in the operator are only needed if the op is used with python - you could use an invalid index as argument. But should always be valid if you use the button in the sidebar panel.

Here's a working script that moves the background image relative to cursor:
import bpy
from mathutils import Vector
from bpy.props import IntProperty, FloatProperty
from bpy_extras.view3d_utils import region_2d_to_location_3d

class ModalOperator(bpy.types.Operator):
    """Move an object with the mouse, example"""
    bl_idname = "object.modal_operator"
    bl_label = "Simple Modal Operator"

    first_mouse_x = IntProperty()
    first_mouse_y = IntProperty()
    first_value_x = FloatProperty()
    first_value_y = FloatProperty()

    def region_to_view(self, context, event):

        x, y = context.space_data.background_images[0].image.size
        aspect_ratio = x / y

        loc = region_2d_to_location_3d(context.region, context.space_data.region_3d, (event.mouse_region_x, event.mouse_region_y * aspect_ratio), Vector()).to_2d() # works for top view only, need axis mapping here
        offset = region_2d_to_location_3d(context.region, context.space_data.region_3d, (self.first_mouse_x, self.first_mouse_y * aspect_ratio), Vector()).to_2d() # ... and here too

        return (loc - offset + Vector((self.first_value_x, self.first_value_y)))

    def modal(self, context, event):
        bg = context.space_data.background_images[0]

        if event.type == 'MOUSEMOVE':
            bg.offset_x, bg.offset_y = self.region_to_view(context, event)

        elif event.type == 'LEFTMOUSE':
            return {'FINISHED'}

        elif event.type in {'RIGHTMOUSE', 'ESC'}:
            bg.offset_x = self.first_value_x
            bg.offset_y = self.first_value_y
            return {'CANCELLED'}

        return {'RUNNING_MODAL'}

    def invoke(self, context, event):
        bg = context.space_data.background_images[0]
        if context.object:
            self.first_mouse_x = event.mouse_region_x
            self.first_mouse_y = event.mouse_region_y
            self.first_value_x = bg.offset_x
            self.first_value_y = bg.offset_y

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

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

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

if __name__ == "__main__":
    register()

Note that it works on the first background image and top view only (you need to add axis mapping, view to screen).


text:
What can the Alpha sliders in cycles be used for?
From my previous question,  I was wondering what the alpha sliders are useful for in cycles. (As they don't seem to effect the shader)

I think it's safe to say that it does nothing at all. It's only present there because all shaders use the standard RGBA selector even though an RGB selector would be sufficient.
In some other areas where only RGB-values make sense, however, RGB-selectors are in use, so it's not great user communication to not use them there I guess.


text:
Is it Possible to Create an Opalescence Shader in Cycles?
Is it possible to make an Opalescent shader in cycles?
From Wikipedia:

Opalescence is a type of dichroism seen in highly dispersed systems
  with little opacity. The material appears yellowish-red in transmitted
  light and blue in the scattered light perpendicular to the transmitted
  light. The phenomenon is named after the appearance of opals.

I attempted to do something similar by mixing to glass shaders with IsCamera ray as the factor:

However, the color of each glass shader is getting mixed, so the color of the object is not separate from the color of the caustics:

How can I make a shader with separate color inputs for the caustics and the object itself? Or if it's possible, make a more physically based opalescence shader?

Update: I managed to separate the caustics from the object with this node setup:

However, I can't seem to mix them. Here are results with the Factor of the last mix node at 0, .5 and 1:

I did not expect setting the factor to .5 to work, though I'm not sure why using an Add node blows it out:

I could composite these together, but I would prefer to have it work in one material if possible.
How can I accomplish this?

Can you change the title? Currently the title sounds like a tutorial request, but the question itself is more specific.

The Problem here is that you have to use two different shaders that both use refraction rays. That makes it difficult to find a separation that lets the one shader cast rays on other objects after doing refraction and the other rays casting rays into the camera after refraction but not cast rays onto other objects.
I found this node setup to work:

Result:

Of course this is not physically correct and somewhat a hack. But with a little extra work you should be able to simulate a rather good looking opalescent shader.

I combined a dark blue SSS shader and a white Glass shader with an add shader, and used an orange volume absorption to achieve this result.

you might want to add a picture of the nodes to your answer.


text:
My "Info Header" was replaced when I went into Node Editing Mode. How do I get the default bar back?
I am working on an animation, and I had to change it to node editing mode for a while, but the file bar at the top of the screen is replaced with the bar at the bottom of the screen that says View, Select, Add, etc. How do i get my "info header" back so i can change my mode to compositing mode? Or does anyone know a shortcut to get to compositing mode? Thanks
Please help ASAP this is a timed animation project I am working on

Related - http://blender.stackexchange.com/questions/24386/how-to-change-the-window-type ?

Info   is a window like any other and can be selected in any window via the drop down/pop up on the left top or bottom of the window. Blue circular icon Info.
Or hover mouse over that list and press keyboard letter i
Is that what you meant?


text:
applying build modifier in bge
Hello everyone I am a frequent user of this forum however I only made an account recently.
In this basic game I am making as a hobby I have made a HUD with a circle that has have gaps, so that it look digital, I used a build modifier to crate the animation of it going around the center, now the problem I am having is when I apply the modifier it doesn't keep the animation. How would I keep the animation and apply the modifier?
Thanks for any help

How would I keep the animation and apply the modifier?

You can't.
Explanation
Applying a modifier means it converts your setup to a static mesh.
In relation to the BGE there are three ways to it deals with modifiers:
Supported Modifier
The BGE can run that modifiers. E.g. the armature modifier.
Automatically Applied Modifier
The BGE applies the modifier when loading the scene into a static mesh. This is like the user presses the apply button.
Unsupported Modifier
These modifiers are simply ignored and have no effect (but might disturb the processing of other modifiers).
Conclusion
In difference to Blender the BGE is not build around Modifiers. To get the effect you want I suggest to look at Logic Bricks (Playing actions, hiding/showing objects, moving object, adding/removing objects).

I see what you mean, I did have my heart set on the build modifier, but I will try the logic bricks


text:
Vignette is distorted and not symmetrical
Situation: I am setting up a Vignette effect for my scene. Like what I do normally, I have a lens distortion node, math node (set to 'greater than'), blur node, and a mix node (set to multiply).
Problem: However, for this scene, the vignette effect seem to have a weird shape and it's not symmetrical either. Below is the result. How do I fix this? Thanks.
Here is my blend file

Creating a vignette can be done much more simple by creating an ellipse mask node and tweaking the size value and then blurring it and multiply it with your image.

How is this simpler than using a method that uses relative dimensions, and thus always has the rigth size? While this works it's not the best option.


text:
Red nodes aren't affecting result
I am creating a lens flare for my scene using the node editor.
I finished setting up all the nodes and had a final render which looks ok. However, when I tried to group it (CtrlG), all the nodes being grouped turned red.
It's my first time trying to group nodes so I'm not sure if it's normal that all the nodes turned red. Moreover all the nodes that is under the group doesn't work when being rendered! the nodes no longer work after I grouped them. How could I fix this?
Here's my blend file.

Those nodes are red because they are muted, which is a means of disabling a node temporarily. M toggles the selected nodes muted/unmuted.
Grouping in your file works fine for me, so I'm guessing you pressed M accidentally while pressing CtrlG.
To fix, just select the muted nodes and press M again.


text:
Non-Uniform Scaling during UV unwrap. What is this?
I've got a problem while unwrapping UVs. When I'm unwrapping UVs it showing me this message.
Why is this happening?

It's because your object has been scaled on some axes more than others in object mode.
For example:

It should be fine, but if you are having problems you could try applying the scale by pressing CtrlA> Scale in object mode. This will apply the object mode scale "offsets" to the mesh data, resetting the offsets to 1 without  changing the appearance of the model. Note that this could affect modifiers such as bevel. See Why are the longer edges being beveled more?

Pressing ctrl+A , is it as like freezing transforms ? Actually  i am from Maya.

@SamirChandraBarma Yes, it is the equivalent of freeze transformations.

It should be fine? No it's not fine at all. It unwraps my entire model into infinitely narrow lines.

@AzulShiva Sounds like you have a particularly extreme non-uniform scaling then. Have you tried applying the scale (Ctrl+A)?

I did. I had to unwrap every face at a time.

@Azul Wait, so scale is at 1,1,1 and it still shows the 'non-uniform scale' message? That's odd..

Yes. And when I try to unwrap it, at first I thought it didn't. But then I realized it unwrapped all the faces it into an infinitely thin line. I'm guessing something went wrong there with the new blender version...

@Azul I don't suppose you could upload the file?

I already unwrapped every face by hand. So I resetted the unwrap with "U" -> "Reset" to get my Unwrap to where it was at the time of the incident, but it unwrapped it just normally. Maybe I should have tried resetting the UV when I got into problems.


text:
Final rendered image is completely transparent
I am rendering in view-port mode using cycles with GPU rendering but the problem is not there:

But when I am rendering a final render, it calculates everything and after some time, it gives this empty result. Why?

When I am rendering a big scene, it calculates everything and says that there is not enough memory on GPU. But I have 2GB of GPU memory.

That usually means you are out of memory. 2GB can get eaten up quickly, especially with lots of textures and geometry.

please answer my first question ?

That is my answer to your first question

Here is the blend file https://drive.google.com/file/d/0B9FnFhTHyZQvNnV2ckxTdzh3anM/edit?usp=sharing


text:
How can I present an array of booleans in a panel?
I'm trying to provide a tool for an artist on my gameDev project.  They should be able to set a bunch of settings in a panel, and then press a button to start an automated export.  I want to give let them set a bunch of boolean values, but I'm having trouble finding a good way to present a lot of booleans in the Blender UI.

I need to iterate over the values in each list, so having a BoolProperty for every checkbox is not an option.
I am not sure what kind of layout.prop would do this well, or what kind of property data structure to use with it.
On the UI side, prop_menu_enum() seems like it would be perfect...can I use it as to hold multiple UI checkboxes?  Otherwise I could iterate over whatever kind of list of booleans I end up with and a property for each one.
On the data structure side, I see there is a BoolVectorProperty, but it doesn't seem to hold names for each value.  There's a CollectionProperty, but I'm getting a error "TypeError: CollectionProperty(...): expected an RNA type derived from PropertyGroup, failed with type 'builin_function_or_method'" when I try to register a PropertyGroup that has a CollectionProperty as a member variable.
I keep getting the feeling that there's some good way to do this that I don't know about (and I know almost nothing about blender programming).  Any recommendations?

You can use prop_menu_item to hold multiple UI checkboxes if you pass the ENUM_FLAG option to the corresponding EnumProperty. Don't specify the numids then. Blender uses powers of 2 for single elements and sums for combinations in this case. (bit field)

It works pretty well to use BoolVectorProperty and then in the UI to address each element by specifying the index and overriding the (empty) text.  I learned this reading http://blenderartists.org/forum/archive/index.php/t-264624.html .
ex:
myList = ["cat", "rabbit", "fox"]

class SpriteSheetProperties(bpy.types.PropertyGroup):
    sets = bpy.props.BoolVectorProperty(
        name = "Sets",
        description = "Which animal sets to render",
        size = len(SETS),)

class SpritifyPanel(bpy.types.Panel):
    def draw(self, context):
        layout = self.layout

        box = layout.box()
        split = box.split(.25)
        column = split.column()
        for i,set in enumerate(SETS):
            column.row().prop(context.scene.spritesheet, 'sets', index=i, text=set)

Doing this over a few different list, I now have this nice box:

You can use column_flow if you don't want to split things manually. Other layout options are listed on the linked page.

authors: Димитър Донков


text:
How to disable Symmetrize in Sculpt Mode?
I enabled Dyntopo, but Symmetrize seems to have been active already. As soon as I start stroking the mesh, it does it double.
I just don't see how to disable it.

Ensure the Mirror axes are all deselected:

In 2.8 these settings are in the Brush dropdown:

I wasn't able to find the dropdown as mentioned earlier, but the later Blender still has settings under Symmetry > Mirror [x][y][z].


text:
Can Blender take two video files and overlay them with transparency?
Can Blender take two video files and overlay them with transparency?
Essentially I want to have a video sequence playing while a 2nd sequence is overlayed and also playing, but that 2nd sequence is transparent (think alpha transparency) in order to see both both sequences.
This might have the effect of the classic film ghost to it, where you can see through the 'ghost' to the sequence it has been overlayed on.
Is this possible in Blender?

Yes, this is possible.
To overlay a video, simply layer one on top of the other in the VSE timeline.

To make the top one transparent, simply use the opacity slider in the properties panel. 0 is for fully transparency, and 1 is for full opacity.

Why the down vote? Could be useful to know why people don't like it so it can be improved.

Well, without having downvoted it, I think you should elaborate a bit more, talking about different blend types for example...

@Polosson Thanks for your input. I added a section on layering (which seemed obvious to me, but I realized it a major part of the question also). I don't think blending modes are really relevant, but thank you for the idea.

Also note that the VSE uses a nonlinear reference space, which means that all blends will be "incorrect", including the original question regarding a cross. To properly blend two RGB images, the internal reference must be linearized.

@TroyJamesSobotka Why is this important? The question was simply about layering two videos, with the top one partially transparent. I don't see why an answer has to be very complex when the question isn't complex in the first place.

Thanks @TARDIS Maker, I'll get to grip with some basics and try out your solution tonight or tomorrow and report back.

Exactly what I was looking for. Thank you @TARDIS Maker.

@TARDISMaker, I talked about blending modes because the OP said "Alpha transparency", and my first thought was "Alpha Over" blending mode. However your answer seems to be the right one!


text:
How do I make BGE recognize multiple XBOX Controllers?
So right now I have a splitscreen FPS on Windows.  I have the players set up by using the Joystick Sensor when the XBOX controller is plugged in.  When I have two controllers plugged in, both controllers control both players.  I want it so one controller controls one player and the other controls the other.  Is there a way to make blender recognize the controller?  If I can't do this than I will have to make it so one person uses the keyboard and mouse and the other uses the controller which would not be as good.

You can use the Index field on the Joystick sensor, to distinguish between different controllers.

Does the index just specify what controller it is ( like a play station or Xbox controller) or does it specify which of the two controllers is two Xbox controllers were plugged in?

From my understanding, it builds an array of the connected controllers; then the index would be the position in said array - meaning it distinguishes between which controller is being used, as opposed to which type it is.


text:
Trying to map UV texture, but shape turns black every time
So I get to the last step of activating my UV texture so that it will render on the face of the rectangle, but when I press F12 it doesn't activate it. It just turns my whole shape pure black. Can anyone tell me what I'm doing wrong? I also included the picture of what happens after I press F12.

Does the texture influence the color value of an applied material?

I firsts suspected the .psd format, but it worked for me. Could it be that you don't have a light source in front? Does the texture show up when you set viewport shading to texture?

@stacker I don't think it's the light. There's a lamp in the object outliner on the top-right.

I see that a UV map is not set in the Mapping section of the texture properties. Maybe that is it?

if there's another material, did you assign the one with your texture in it?


text:
How do you download a blender addon

So I wanted to download the blender add-on sapling, but I can't figure out how to download it. I would really appreciate if someone could clarify how to download the add-on.

The sapling addon is included in the newer versions of Blender (2.7+)

Is seems that you accidentaly found a bug report on the addon you want to download. There is no download button. To browse available addons go to the Scripts Catalog. In case of the sapling addon it wouldn't be neccesary (see @cegaton's answer).
On the addon's page you find a download link:

For installation see:

http://wiki.blender.org/index.php/Doc:2.6/Manual/Extensions/Python/Add-Ons
Installing an addon

You can browse the git repositories with Phabricator, the sapling addon is located in rBA (Blender Addons): https://developer.blender.org/diffusion/BA/browse/master/add_curve_sapling/. It's easier to download multiple files with git itself however.

@CoDEmanX If we just had an addon which allows to assemble a download from all sources like http://blenderaddonlist.blogspot.de/

You may also notice that the addon pages still point to svn.blender.org which now is only old versions.

As has been mentioned the addon you mention is included in blender. There are however addons that are in blenders-addons-contrib that people may be interested in downloading and testing. The contrib addons are in development and have not been accepted to be included in stable releases.
There is an overlooked method to access individual addons from blender addons-contrib repository, which can also be used to download updates to official addons after releases.
Start by going to git.blender.org, in the available list select the project you want to look in (blender-addons-contrib.git), at the top of this page click on tree.
Here you can see single file addons have a raw link to the right that you can use to get the file. Items listed as links are folders of more complex addons, if we take one as an example (add_mesh_building_objects) clicking it will show the files that makeup the addon. At the top of the page you will find a snapshot link that will download the folder you are looking at, without downloading the rest of the repository.

You can then unzip this tarball and place it where blender will see it. You may also want to rename it as the folder name will be misleading. The install addon button fails at this point as blender only accepts addons in .py or .zip files and this download will be in tar.gz format. You could unzip and then zip as a .zip file to use the install addon button.


text:
Problem with UV Mapping in cycles
I recently started having problems with UV mapping. I map the object on the same color yet it has different shades of the color. For example I was mapping a car I'm making for a game and it looked like this.
The interior of that car should all be one gray but it ends up as different shades of gray and some brown even though they are all on the same part of the texture (the texture is only 9 px by 9 px).

We'll need more details including screen shots of your uv maps etc.

http://gyazo.com/afe9c9a12550690ee50177c3a4b1855a it's only 9x9 pixels, it's small for the game

I'm still having a hard time understanding what the problem is. What did you expect it to look like, and how does that differ from what you're seeing?

The interior of that car should all be one gray but it ends up as different shades of gray and some brown even though they are all on the same part of the map

Try  pressing (Ctrl+N) in edit mode of the mesh while all the mesh is selected, that will recalculate all the normals, also very important press (T) and in edit mode of the mesh while all the mesh is selected find button Remove Doubles. If non of this work try unwrapping the object again.

Comments are not for extended discussion; this conversation has been moved to chat.


text:
Problem With Jagged Edges When Using Boolean Difference
When I go to use a Boolean modifier, some edges are jagged but the model doesn't seem like it would cause that.

This is probably because you have four faces on your plane at the top, and only three on the object that you were trying to boolean difference with. It's like when you try to sharpen a regular eight-sided pencil. The edges are always jagged.

thanks! I have a problem thinking about it but I added another side and it fixed it right up :)


text:
Edit multiple text objects with python
I have 50 texts objects, each text object has 2-3 lines of text, is there a script that would allow me to enter a text in the script and it would change the text

I didn't really get if you wanted to change all the texts to the same thing or if you had input phrases and wanted to populate your texts with but her's solutions to both :
import bpy

for obj in bpy.data.objects:
    if obj.type != "FONT":
        continue
    obj.data.body = "This is my first line\nThis is my second line\nAnd my third"

import bpy

paragraphs = [
    "This is the content of my first text",
    "This is the content of my second text",
    "This is the content of my third text",
    # etc.
    ]

for obj in bpy.data.objects:
    if obj.type != "FONT":
        continue
    obj.data.body = paragraphs.pop(0)
    if not paragraphs:  # We used all our texts
        break


text:
Where is the "See Through" selecting button in 2.81?
In blender 2.81,Layout workspace, Edit mode, Face select,using Box-selecting tool, I try to select all the faces of a cube at once, but only the front faces are selected.
Blender 2.79 had a "See Through" button next to the Vertex,Edge,Face buttons allowing to select all at once .
Is there such an option in 2.81? I could not find it.

Mark the answer as solved please.

It's still there.
Right next to viewport shading options.
Now it's called X-Ray.
Works in Edit and Object mode.

Thank you very much for this very fast and very useful answer

Glad to be of help :). You can now mark the question as solved, for other lost souls coming from Blender 2.79.

@aguarneri Please don't just add thank you as a comment, upvote the answer instead. If you feel it completely solved your problem consider marking it accepted


text:
Eevee - Mesh light illuminating scene from within glass (i.e., light bulb)
I'm trying to light a scene in Eevee using light bulbs. I have a filament (emission object) within a glass object. Basically, I'm able to see the emission object through the glass, but the light is not escaping the glass to illuminate the scene. Here are two renders. In both cases, world lighting set to 0, no other light except the emission ball in the middle. Glass ball has a small solidify modifier to make it empty inside.
Emission ball outside of glass ball. Note you can see through glass ball, and emission ball illuminates scene.

Emission ball within glass ball. No exterior illumination.

Note light probes are used for illumination from the emission mesh, and the reason the cube within the ball in the second one is not illuminated (even within the glass ball) is because there is no probe within the glass ball.
Tons of references on glass shaders, but nothing specifically on this question as far as I can find. Only one reference I've found to this is "turn off any glass during baking". Is that the only option? Is Eevee not capable of what I'm trying to do?
Blend file: https://drive.google.com/file/d/1276SA_p_O1R8LkjM41ZtZCjCPKUJCvr0/view?usp=sharing

Couple of things to note here.

Mesh lights do not work in EEVEE the same as Lights (mainly they do not cast shadows). I've pointed to it here: In Blender 2.8, how do I light an EEVEE scene with an HDR?
You can use Point Light to have effect you want without baking anything. Use Radius and Strength to manipulate it.
You need to turn on Screen Space Reflections with Refraction for your scene:

For the Glass material you need to properly set below options to be able to see light source and allow it to light the scene:

Keep Solidify modifier on the Bulb object. What is strange is that even with value 0 it is working fine :)


text:
How to I transfer a video from Node editor to the 3D View?

(I'm new to blender)
So I've erased the green-screen off of a video in Node Editor.
Now I just need to use the actual video and animate it in the 3D View. But I don't know how to transfer it from the node editor to the 3d view.

Hello :). I'm afraid it's not possible to link images/videos from compositor to the 3D viewport. The compositor is applied on top of your renders. You can, however animate it first, and then mask out the green screen in the compositor.


text:
camera_to_view_selected() only selects a small section of the object in a script, works fine when I manually use the console
Here is the code I am using (in a python script):
for obj in bpy.context.scene.objects:
    obj.select_set(False)

for obj in bpy.context.visible_objects:
    if not (obj.hide_get()):
        obj.select_set(True)

bpy.ops.view3d.camera_to_view_selected()

bpy.context.scene.render.filepath += "image"
bpy.ops.render.render(write_still=True)

Which produces this result:

But if I manually go into blender and paste the code in, I get this result (excuse the textures/colors being messed up, I was just too lazy to manually adjust everything):

Which is the result I was trying to get using the python script by itself. What am I doing wrong?

How are you calling / using the Python script in your first case? It works fine when bpy is imported first.

Hello and welcome to the site! Could you please elaborate a bit and maybe explain what the script is supposed to do? And in what ways does the actual outcome differ from the expected one? That way one does not have to try and retrieve this information from the python script and images by themselves, but rather have the right idea of your question right away.


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Background hdr image is covering up model when rendered
Making Gold object but background hdr image is covering up model when I render. I am using cycles render and am trying to make my object have a gold appearance so I uploaded an hdr image in the world tab but now this image is the only thing I can see when I render. What should I do?

Could you upload some screenshots or a .blend?

First picture my model, second picture what happens when i render

If you add other objects, are they rendered?

There are many possible causes I can think of, but without more information I can't say which it is in this case. The easiest way for us to troubleshoot your issue is with a .blend..

@gandalf3 Could you put them out there anyway, this user clearly doesn't want to upload the .blend.

There's obviously nothing wrong with not uploading your .blend, but it would help a lot. You could delete everything except the parts necessary to reproduce the issue, if that helps..

There are many things which could cause this, but here are some of the most likely ones (not including the ones already mentioned by GiantCowfilms)

A Modifier disabled in the viewport could be hiding/messing up the object(s) only in the render.
As GiantCowfilms already suggested, it could be a renderlayer issue. Having all layers selected does not mean your object will be in a renderlayer, the layers specified under layer are the ones which are used in rendering:

In the above case, only layer three will be rendered (objects on layers 1 and 2 will not appear).
Use surfaces could be disabled:

A transparent material be used somewhere, such as the material override slot.
A problem with the compositing setup could be excluding your objects from the composited result.

There are all sorts of unlikely scenarios which could cause this, so there's really no possible way to list them all..

Troubleshooting
To help troubleshoot this, here are some things you can try:

Are the objects rendered in viewport render (ShiftZ)?
If it does, then this suggests it's something on this list.
If you add a new object, is it rendered?
If it is, then that suggests it's something object specific (not a renderlayer/compositing problem)

Hold on it worked for a second then the screen goes black on the render at the very end...

Without a .blend it is hard to say for certain what the issue is.
Here are some possible causes:

You're rendering on the wrong render layer.
You turned off your objects render visibility:
You disabled your objects visibility to the camera in the ray visibility tab.

Ray visibility is on too :( How could i be rendering on the wrong layer? Both the hdr image and the layer I am on is active

@user5344 Could you post a .blend, I can't think of any more causes.


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How to make a Portal Bridge material in Cycles?
it's one of my 'How do I make a material in Cycles' questions again :D
I am still not that wise when it comes to transparent textures and fresnel and so on, so if someone could explain to me how to create an effect like the one shown in the image below, that would be great ^^.

Translucency and diffuse shaders with some textures.

Basically you can just mix between some emission shaders and transparent shaders based on some textures (click for larger image):

This uses a tile able image to create the sine-wave effects. I used a procedural gradient texture and a color ramp node to create the bright edges, and a noise texture to give some basic variations.
Note that a separate emission shader is used for illuminating other objects, in order to make illuminate other objects better without over exposing the object itself.
The image texture I used was this rather poorly hand painted wave. It's probably possible to procedurally generate such a wave with some math, but I'm not sure how..

In order to create a glow/bloom effect, I would use the compositor. You can either use a quick glare node, or manually blur and add the result back to the base image. For good measure I also mixed in some ambient occlusion and some fog/depth glowy stuff.

Result:

Example .blend

nice approach but not quite like i would want it should glow more.

I'd recommend using the compositor for that. I'll update my answer in a second..

how do they achieve that ingame ? i mean is there some kind of live comopsitor in engine or what ? ^^

I don't know, but that probably isn't too far off. It's what's called a bloom effect, and is usually a 2D blur added on top of the base image.

hmm okay im waiting youre answer :D

@TheCycleOfBlend Done.


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How to make Feathers for a Gladiator Helmet with Particle Hair?
I have here my wip of a Gladiator helmet and I would like to know how to set up a hair particle system to a point that I would like to achieve. And of course I would like to know how to make a good looking cycles material for it.
Here are some reference images and a screenshot of my mesh.

i dont know at all what i can do is just click on create and switch to hair i dont now how todo so the hairparticles have a nice curve and not the default and i dont know at all wat vlaues i should use in root and tip and so on.

Note that these kinds of questions are controversial, see http://meta.blender.stackexchange.com/questions/476/should-we-expand-our-scope-to-allow-simple-howtos

And http://meta.blender.stackexchange.com/questions/62/regarding-questions-and-answers-as-tutorials

yes make youre scope bigger when the answer isnt to complicated.

I don't think a Thracian helmet would have feather quite like that.

I would use a separate mesh for the emission of the hair particles. This allows for more flexibility and ease of customizing the hair later.

Add something like this on top of the helmet to act as the hair emitter:

You might want to separate part of the helmet mesh to ensure that there are no gaps between the emitter mesh and the actual helmet object. You might even want to put the emitter a little bit inside the helmet, just to be extra safe.
Add a particle system and change the type to hair (1). Also disable emitter so that the emitter object doesn't appear in the render (2), and enable child particles (3).  I used interpolated child particles, but this depends a bit on what you want to do.
Note that Simple child particles can result in floating hairs if you are not careful, especially on curved surfaces.

Note that I also tweaked the child particle settings to add a bit of randomness, so that the hairs are not all perfectly straight.
Add a material to the emitter. I used a simple translucent material:

Back in the particle settings of the emitter object, tweak the thickness and scale of the hairs as desired. You'll have to play with these settings a bit to get a feel for how they affect the render, but it should be pretty intuitive for the most part (e.g. thicker hairs will make it so less light can get through, making the hair appear more dense/dark in the render)
I went with a more uniform hair thickness, only tapering the thickness a little bit towards the ends of the hairs:

Example .blend

lol dude that looks really great you da MVP.


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When can a Color Ramp be used to create a gradiant in a Cycles shader?
When can you use a ColorRamp node or better to say where can you use a color ramp to manipulate the color of the mesh to be a gradient and not solid?
I tried to plug the ColorRamp in to the Color input of the Diffuse shader, but I didn't get a gradient, instead I always got one color.

The ColorRamp node only remaps existing information. So without an input, you will only get a solid color as output (the solid color in the middle of the ramp, to be exact).
This is easily fixed by providing an input, such as a procedural gradient texture node:

itsh ard for me not to say thnaks to you lol. Yeah i know me and my usefull comments.The funny thing is i wondered how do i give this Gradient texture Color :D

by the way is it possible to import gradients ?


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What is the easiest way to have a default "Good" lighting setup for cycles?
Can I have a not too dark scene in Cycles at Startup?
Because I'm not so good at lighting. Two I don't want to mess with it every time. Three I want to have a Quick Way of seeing how my model looks in Cycles.
The lighting Setup at start is great in programs like Keyshot and Marmoset Toolbag; you can load every model in it and it will look good from the start.

Every Blender artist should read Ben Simonds article, Lighting Tips From the Masters.

yes i know when i need serious lightning at the final render then ill make serious lightning but before that i need quick results ya know ?

See: http://www.blendswap.com/blends/view/74897

I usually keep some generic lights on a hidden layer in my default .blend, so I can just enable that layer to get an instant light setup.
To do this:

Open a new file (⎈ CtrlN)
Create your light setup:

Here are some good tips on lighting.
There are also some nice light setups in the community if you don't want to make your own.
Move the lights to another layer (M), then save the startup .blend (⎈ CtrlU).
This will save the current file as how blender will start up by default, so make sure everything is how you want it (visible layers, selected objects, view orientation, etc.)

Another thing you can do is use HDR/environment lighting.
You could try this addon, or use HDR panoramas such as these as environment textures.
To do this, add a HDR environment texture to the world surface (1) and (2) (it doesn't matter whether you add it in the node editor or the properties editor). There are no lamps in the image below:

Also remember to enable Multiple importance sample (3) when using environment textures, otherwise you will probably get a lot of noise.

Three point lighting is the way to go, not just randomly placing lights...

@someonewithpc Ideally you would make a specialized light setup which suits your scene or model, these are just some ways to quickly have some light so you can see :P


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Objects not appearing when I render my model
Objects do not appear when I render my model in blender 2.71. All objects are set to appear when rendered. Pressing W and clicking Clear all Restrict Render doesn't work, either. I only get a background when I render.
Edit: There are no strips in the VSE and all correct layers are set to view when rendered.
Blend file: http://www.mediafire.com/download/f5y51klyo9otdd1/Cycles_render_room_in_aero_apartments_elevator_lobby.blend

Make sure the correct layers are specified in your render layer(s) and that you have no interfering strips in the VSE. If those don't solve it, is it possible you could upload your .blend?

You don't have light in your scene.
The hemi lamp in the middle of the room won't work, as cycles doesn't support hemi lamps yet. It will be treated like a sun lamp.
Sun lamps provide a uniform amount light from infinitely far away in a specific direction with no falloff. Because of this, the position of the lamp doesn't have any effect.
Since the room is completely closed and light has no way to get in from outside, everything renders as black.
If you change the lamp to a point lamp and increase the strength to something like 1000, you get something like this:

Thank you very much. This fixed the black. Now I can see my first four modeled blender elevators when I render an image. Yaaaaayyyy.

@Cyborggeffien If this answer satisfactorily answered your question, consider marking it as accepted by clicking the checkmark next to it. :)


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My Blender has no Header
When I opened Blender after installing them, I felt that something was wrong.
then I realized that the awkwardness came from how "empty" it was(See the picture below).
Does anyone know how to fix it and/or why it happend?
 As you can see, my Blender has no window, whats so ever.

This kind of thing can happen when there are issues with python, but the weird thing is that it looks like the outliner is unaffected..

The Outliner is entirely written in "C", that's why it is unaffected when something is broken with Python.

Did the Ui show up before? Best way is just reinstall it or use a zip(portable version).▼Download

@Leon95 I reinstalled it and yes! it worked! Thank you for your help!

While I have no immediate answer, here is how you can find out the cause of the problem:

Open a command line shell.
Navigate to where your Blender is installed.
On windows you can Shift RMB in the blender program folder (without any file selected) in Windows Explorer and select Open command window here.
On linux this step is only necessary if you have multiple version of blender installed, otherwise you can just run blender.
Call blender from the shell. On windows, type blender.exe. On linux, type  ./blender.

Now Blender starts and leaves messages in the commandline shell. You will probably see one or more error messages which may lead you to the cause of the problem.
You can try to force Blender to use factory-settings by providing the commandline option as follows:
blender.exe --factory-startup

Some possible causes are:

a broken Addon
An installation error like: "out of disk space", "no write permissions on disk", etc.
Wrong Python version in Path (i am not sure if Blender gets trapped by that)

Even though I didn't get an error message, when I reinstalled it, it worked! Thank you for your help!

It looks like the window is either maximized or blender is running in fullscreen mode.
Did you try CTRL + down-arrow or ALT + F11?


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Why are keyframes in global coords, instead of local coords? (Blender 2.70a)
So, I've been using Blender for several years, including a fair amount of animation, and in the past it's always been useful to align an object with its local coords. I.e. having the y-axis pointing down the nose of an airplane makes it much easier to animate.
However, I recently noticed that the keyframes aren't recorded in local coordinates (anymore?), but in global coordinates. This makes animating off-axis rotation very difficult.
Changing the rotation mode doesn't seem to help (Euler, quaternion, etc.).
Unfortunately, I can't upload any examples because the project is proprietary, and I don't really have time to setup another animation, but the example goes something like this: I want to animate a record rotating in a record player, but the player is not sitting flat, it's tilted at an angle. Normally, this wouldn't be a problem. Just model the record with z up, and you can tilt the record at whatever angle you need so that it sits on the tilted player, and still rotate the record around its own z-axis, right? Unfortunately, this is not what's happening. Instead, I animate it rotating 180d twice and it wobbles all over the place because it's interpolating global coordinates, not local coordinates.
EDIT: Here's a demo afterall: https://www.youtube.com/watch?v=nimTjEYwcnE
It maybe a little hard to see because it's so fast, but the second time I animate the cube, it wobbles instead of rotating around its own z-axis like I expect it to.
Does anyone know what magic button I pressed that did this?
Or am I just crazy and remembering something that has never been possible? It's happened before...
EDIT: In fact, I KNOW this has worked before, cuz I just went back and looked at some old stuff, and I know I animated using the local coordinates then... I'm gonna go see if 2.70 behaves differently from 2.70a...
EDIT: Nope, 2.70 behaves the same way.

I didn't know you could use local coords :P (Though I have not done much animation, so it's more than possible I just don't know..) What I would do in this situation is use a copy rotation constraint to copy the Z rotation of an empty in world space and convert it to local Z rotation.

That might be the best option for now, because I'm pressed for time, but this feels like something Blender has done before, and something it should be able to do. Turns out, it's easier to demo than I thought. I'll add something shortly.

You would usually parent the rotating record to another object (keep transforms?), can be an empty, then use that other object to position and tilt the rotating object. It will rotate around its local axis.

Interesting... So each of those rotation methods allows for ONE axis to be directly controlled. I could have sworn this used to be easier...

Sometimes this problem can be "solved" by choosing a different Rotation Mode.  "XYZ Euler" is popular (because it is the default), but sometimes people pick a different one, either to avoid gimbal lock, or to achieve a particular animation effect.
However, the general purpose solution is to use parenting, either the genuine object parent field, or a Child Of constraint.  You tilt the "parent" such that one of its axes is what you want to rotate around (lined up with the spindle of the record player), then animate the rotation of the record around a single axis.  As you can see from the many comments, there are a couple of different ways to accomplish the effect you want, and each one has its pros and cons.
The Humane Rigging series has a few videos that might expand your understanding, the one I'd start with is Humane Rigging Chapter 3 part 3 although you will probably want to watch part 2 and 4 when you have some spare time.

What if I want to do it without rigging?

The rigging videos cover useful concepts that are not restricted to rigging.  Especially rotation schemes.


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How to make textures follow a certain path?
I'm working on a fountain made of cobblestone. The base is currently a single object. You can see the the base in full here:  (ignore the clipping of the texture for now, I'm still working on the UV map).
What I'm trying to do now is make the texture pattern on the top of the base to follow the ones on the side, so it seems like it's actually made out of cobblestone bricks. If you move the fountain around a bit, you can see that by coincidence the bricks match up, but it makes clear what I mean:
How would you do such a thing? It would be really helpful, thanks!
If it matters, I'm using cycles render.

wow what you ask is hard, and maybe you should make your cobblestones concentric? It would be more logical to build a fountain this way

@moonboots I've been thinking about simply 'building' the fountain using separated bricks, but I was curious if there was a common practice for stuff like this.
Also what do you mean by concentric? I presume that you mean to project the stones around a centered axis on the texture?

I mean the stones rotating around and not aligned. You could build the fountain, then bake the normal to use it on a low-poly version, you could also try the UVmapping and use the F-Clone brush so that you can make some manual corrections.

Also see https://blender.stackexchange.com/questions/74041/how-to-perfectly-align-uv-coordinates-automatically . It is not hard to achieve, just unwrap following active quads, then it will require some adjustment by scaling to match the sides to the top.

@DuarteFarrajotaRamos https://blender.stackexchange.com/a/78362/20394 did it! Thanks a lot! I'll edit my question to point to the answer.

Don't edit answers into your question. If an answer helped you upvote it, if you found an yourself answer post it below in the answers section with a short description of the procedure

@DuarteFarrajotaRamos The reason I edited my own question was because you're answer was a comment. It felt wrong to simply write my own answer with the link you provided and then mark it as the correct answer as that would not credit you but me (even if I mention you, the upvotes of the answer will go to me). It just felt wrong, but if you're ok with it I'll just rewrite it into an answer!

I don't care much for votes, credits are less important than knowledge. That is the purpose of upvoting existing answers, this way the system will read this question as unanswered and it is less likely to help anyone else searching in the future.

@DuarteFarrajotaRamos You're awesome, I'll edit the post. Thanks again!

I need to wait 22 hours before I can accept the answer so I'll do that tomorrow.

Thanks to this answer: https://blender.stackexchange.com/a/78362/20394 from Duarte Farrajota Ramos's comment, I was able to get the effect desired.
I just followed the steps in the gif linked above, and instead of selecting one face I selected the row of faces inward of the circle to the outer of the circle, proceding to do the rest of the steps from the gif.
It worked!

You should use unwrapping and UV mapping.
You need to open the texture in the UV/Image Editor, and unwrap the mesh on it making it follow the pattern.
If it's your first time with UV mapping and unwrapping, watch this.


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A single object in Blender = multiple objects in Pepakura
As the title says, after using the Ctrl+J shortcut to merge several objects into one, and exporting to OBJ and then opening in Pepakura Designer, it acts as if I never connected them at all.
It's a helmet, and more specifically, the unfold in pepakura unfolds all of the separate objects and, if i managed to assemble all of the parts, I'd finish with 6 unconnected parts instead of a full connected helmet.
So, can anyone help me? I'm extremely new to Blender and have no idea what to do. I've been looking for a few days now.
Thank you all.

It probably only allows objects to have one mesh, whereas, in Blender, an object can have arbitrarily many.

Thanks for your reply! How would I go about making it one mesh, then?

By actually connecting the individual parts, vertex by vertex. Is it really crucial that it be one piece? You can probably parent all the pieces to a placeholder or something

It being one piece makes everything easier. Also, how would I go about doing anything you suggested? I have no idea what to do at all. Thanks!

It's the boring process of selecting a pair of vertices to merge and pressing Alt + M

Unfortunately, when I do that it horribly deforms the piece.

Assuming that you are using .obj file exange format, Pepakura will import the object exported from Blender as a single object if in blender you join all the geometry in a single object.
Pepakura is an unfolding software. Starting from the given geometry,it caluculates the angles and suggest where to put seams, add labels... but all rely on the initial geometry. If you give it two disconnected pieces, even if they are "the same object" they will be considered disconnected, so their boundaries will obiuvsly be seams.

Notice in the images above how pepakura ignores the fact that the cubes are intersected and cosider them as two disjoined cubes (as they are also in Blender, evon though they are stored in the same object).
You should work on your geometry and make all the pieces that you want be connected a whole.
You can use:

Boolean operations
Bridge edge loops, or add faces manually or with F2 add-on if the borders are distant
Remove doubles, if border are almost in the same place
etc...


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Baking textures: Circular Reference in texture stack error
I'm getting this error when I try to bake textures on my model. It says "Circular reference in texture stack". I found some info on the net. It says I should disable a texture in the texture stack so Blender won't write the texture on itself. But I don't have any textures in the texture stack. I only have simple materials, no image textures. I'm using Blender Internal, 2.75a. So what should I do to bake the materials into textures? I'm attaching 2 screenshots. The texture is rendered partially, I don't know why. There should be more green and also white (there are two materials on the object, green and white), but it stopped halfway. Also note: I did make an empty image for each UV I unwrapped, before baking.
Screenshot 1:

Screenshot 2:

Are you using blender internal or cycles engine? Either way, I assume you want to bake the result for the model into the same texture. If so, you don't need to create several empty textures but just one that has to be assigned to the material.

I think he uses Blender Render engine

One example when this occurs is when the receiving image is used as a texture e.g. (has been unchecked) the issue can be reproduced by checking the enable/disable checkbox.

Either way baking worked

But how do you select the "receiving image"?

@Thomas it has been bugging me for a long time untill I saw this https://www.youtube.com/watch?v=HiASMYoZ9Sg

This problem have been bugging me for as long as I remember. The reason is simple : that error occurs when Blender is told to bake a texture on an image that is already used as a texture hence the term 'circular reference'. It's like trying to film a monitor that shows the footage from the camera you are filming with (I don't know if you understand that :D ). Basically what happens is that Blender 'reads' the data from all the image textures that are used by the material and composites the output into your 'output' image and this error occur when your 'output' image is one of the image textures of the material.
Now the problem is "How to choose this 'output' image", right? Because sometimes, Blender 'seems' to choose kinda randomly the output image to one of your images textures and you have no idea about how to change it. So here is how I do to make sure that I select the image I want for the baking output :
In Blender (the Blender Render engine), we have what we call 'face textures' and the image that is selected as a face texture is the one that will be choosen for the baking output.
In this simple scence, there is a plane with an image texture applied, you can see the texture by selecting 'material' or 'texture shading mode'. The texture you see is NOT the face texture I am talking about, to see the face texture, select 'SOLID SHADING MODE' and go to the 'N' panel to the 'shading' section and check 'textured solid' :

Make sure you are in solid shading mode before doing this, otherwise you won't see the 'textured solid' option. For now my plane has no face texture applied and that is why it is shown bright white in the viewport. if I try to bake anything at this point, Blender will choose my image texture as an output by default and I would get that 'circular reference' error.
Now, split your window and change the second window to an image/uv editor if you haven't already. If you switch to edit mode now, Blender will open automatically the face texture of the selected faces in the uv/image editor on the left. If you have no face textures yet, the uv/image editor will still remain empty with nothing but the UV layout of your object.
If you go to the uv/image editor and chose an image to display, Blender will apply this image as a texture to your object (You need to stay in edit mode). This is how you chose a face texture ( and the baking output).

If you want a blank image for baking, just add a new image from here (without leaving edit mode) and you should see your new image applied as a texture on your object. Note that this operation will have no effect on your renders since you didn't touch your material textures and you should still be able to see you material textures in 'material shading mode'.
After doing that, Blender will use that face texture as an output for the baking process, so if the image you chose is not used anywhere in your materials, it should not emit an error.
Sorry for the very long answer but I hope it helps someone.
Someone on Blender artists posted a link to a tutorial that explains face textures in details and this tutorial is the one that helped me solve this problem. A link to it : An awesome tutorial

For me it was the opposite.
With the receiving texture enabled (box checked) I received a 'Circular Reference in Texture Stack' error.
Without the receiving texture enabled (box unchecked) I received no such error and the bake completed successfully.


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How do I straighten UV maps?
How can I straighten ALL the vertical UV lines at once? Is there a hot keyshort cut? Or if I have to do them one by one .. is there at shortcut for that? Thank you!

A bit related: http://blender.stackexchange.com/questions/23293/uv-coordinates-on-a-deformed-plane

There's an addon for straightening UV maps - http://blenderaddonlist.blogspot.com/2015/05/addon-quad-unwrap.html. Didn't test it though, but may be useful.

And here is a paid add-on: https://cgcookiemarkets.com/all-products/uv-squares/

It's curved in the first place due to the angle of your view. If you view it straight on (press numpad 1) it should be straight. See http://blender.stackexchange.com/q/6758/599

The UVSquares addon is designed to do this easily. Select the uv's you want to straighten out and click a button.

Awesome! You just saved me so much work! Would you consider writing what the rest of the buttons do?

Is this a paid add-on?

It is released under GPL, you can download a free copy from github and if you think it is good enough and want to support the developer you can pay for a copy through CGCookieMarkets.

There is no shortcut for that unfortunatelly.
You may do it using pinning and repeating the scaling of the edge loops with Shift+R shortcut, although it isn't a fast method.

In Uv Editor select the corner of the UV island, press Shift+S-->Cursor to  Selected. Change the pivot type to 2D Cursor. Select the bottom edge of your island and press S,Y,0 to straighten it. Now press P to pin the selected vertices. Do the same with upper, left and right edges. Next, go to the 3D View window and unwrap your mesh again.

Now straighten the other edge loops using Shift+R command. Change the pivot type to Median Point, select the edge and scale it as described above. Then select another edge and press Shift+R to repeat the scaling process.

Related answer that uses another method: http://blender.stackexchange.com/questions/65565/straighten-the-series-of-vertices-in-uv-editor

In Blender 2.8, you can also do it with the built-in addon MagicUV.
Here is a simple geometry I created.

The red lines are the marked seams. In the UV editor, you can see the original UV was not straighten.
All you need to do is select an end edge and press N > in Magic UV Tab > in UV Manipulation check Align UV  > check Transmission > hit Straighten or XY-axis.

And the line will be straighten.

Not always applicable, but worth trying if your UV map is already nearly gridlike: Make a very tiny temporary image, with as many pixels as your mesh has columns, and enable snap to pixels, then select all your verts and drag them around. There will probably be some hand cleanup afterwards, though.


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How to copy paste parts of Themes Setups from one theme to another?
Is it possible to copy part of Theme colors schemes from one preset to another (eventually via notepad) to get an almost perfect theme ?
I ask because the quantity of the possible color selectors is huge.
An organic Theme builder would be great possibly clicking on a part of the interface to choose automatically the selector so you can make changes on the fly, manually doing this is annoying, and usually gives fancy results due to the speed one try to do things to avoid boredom.

Well as far as I know there is no builtin mechanism to do this, at least not directly through the blender UI or in a graphical manner.
You can copy individual colors from one theme to another, by hovering your mouse cursor over a color box and pressing Ctrl + C and Ctrl + V, but I don't think this is what you expect.
Other than than, Blender themes are simple XML files, you can edit them externally using any regular plain text editor.
You can theoretically copy and paste at will between them. If you use some sort of programmer's text editor with syntax highlighting for XML files and possibly code folding for easier navigation it should make the job somewhat easier.


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How to create a gradient texture from one material to another (opaque to clear)?
I am trying to render an object that has opaque base and gradually becomes clear/translucent at the top in Blender cycles.
Please see the attached image (which was not made with blender).

I see two ways that may be possible but not sure. 1) You could divide the cup into 3 parts from top to middle to bottom. The bottom is dark, middle is light dark and top is clear. 2) I would instead use the more tedious method but better than method 1. I'd use textures which requires UV Mapping or I'd use vertex groups and weight painting to achieve the same goal as above.

If I'm in a lazy mood I'd play around with stuff and randomly get the affect lol.

I think you should modify your question to require that the gradient work with the mug at any angle in the scene. Some of the answers will only work if you don't move the cup. You want the gradient to operate at the local coordinate level so that you can move the object and the material still looks correct.

All you need to do is use a Gradient Texture (see how to create it procedurally here: How to create a gradient texture?) as a mask for the transition between two materials.

Set up the nodes as pictured below. Try to experiment with a Mapping Node settings (adjust the Location, Rotation and Scale parameters) to achieve a desired effect.

To have a better control between materials transition add a Color Ramp node and experiment with its slider.

All you need are a two shaders the opaque (Diffuse node), and then the transparent (Glass node), then a way to mix them together.
Here I'm using the Z axis of generated coordinates. Generated coordinates always go from zero to one along each axis of the object.
The color ramp node is to fine tune the mixing between the two shaders.

the transition seems to be based on the height of the shading point and for that we use the Z component from the Position output in the Geometry node and using division ( math ) node we can normalize the height , then we use this as an input for the mix shader to create the transition between a glass material and a diffuse material:

result :

The downside to using the position output is that you have to scale it based on the position and scale of the object.