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Regarding Baking
This is iPHONE model I've made in Blender:
https://www.youtube.com/watch?v=8gfES8_tEF0
While I tried to bake the diffuse map of the model I'm getting an unexpected result. Only the Apple logo and camera is baked into the image. Rest is simply
black.Anybody have any idea?Is it a bug?
Can somebody check the file and help me?. You can download the file here:
https://drive.google.com/open?id=19FNL6wrKAa7LueqQux0XCyJLFUm_q2Aw

(a)Maybe things have changed over the past couple of years but so far as I know transparency isn't bakeable yet so the screen area will need special handling.
(b)At the back of the model, the part with the material named "Frame(Backside).001" and the part with material "Back Cover.001" are nearly overlapping.
That overlap is bad for any type of rendering because the floating point precision limit makes it difficult for the renderer to know exactly where both parts are in relation to one another because both parts are essentially in exactly the same place once numerical imprecision is considered.
You can get away way with using close flat polys for a camera render if the model and camera are close to the grid center and to each other but still; super close, parts flat parts should be avoided.
This type of error is called z-fighting.
And I believe it's why the those parts are coming out black when baked.  They overlap and so both are being baked as if they are each inside the model and hidden from the light.  The baker can't tell which one is outside and which one is inside where it's dark.
I think the overlapping geometry also causes BVH(bounding volume hierarchy) build issues since Blender froze on me when I tried to bake the model. BVH is a spatial partitioning optimization technique.
I forced Blender to shutdown and then my OS crashed.  Bluescreen of death.  The freezing of Blender took place right at the beginning which is when the BVH build takes place.
Anyways, once I separated all the parts and moved them to their own layers and baked them one at a time to look for issues, the BVH freezing no longer happened and everything baked with lighting applied properly.  There were no black parts showing up in the bake.  There were some errors on one of the pieces but that looked like a UV-mapping error and I didn't try to track it down. That's a separate topic and this is all long enough already.
(i)You can either baked all the parts to their own textures as in Diffuse_0.png, Diffuse_1.png, Diffuse_2.png, etc, and then combine them all in a 2D photo editor like Krita, GIMP, or PS. using part masks or...
(ii)You can also UV-Unwrap models with complex pieces as separate parts right from the beginning of the process so they can easily isolated and baked.  Once all the pieces are baked, you can then join them and and create a second UVMap. Now set all the materials to be Emission shaders which acts as a simple image color passthrough and then bake the pieces all to one final UVMap set like what you have in your model now.

You made things too complicated by trying to bake nine materials, a model with hidden parts, multiple types of shaders(Diffuse, Glossy, Emission, Transparency) all at the same time.
And since you can't bake transparency(so far as I know) you have to handle the screen manually after everything is baked.
(a)You can either bake an alpha mask(transparency mask) or use the rectangle tool in a 2D editor to select the screen portion of the image and make that area transparent.
(b)To bake an alpha mask, use a temporary Emission shader that can mix between black and white and apply that material to the entire model.  Set anything opaque to be white and the screen to be black.
Now in a 2D editor, this baked transparency mask can be pasted into the alpha channel.
On a side note, that large back piece that is hidden inside is just a waste of uv-map space, it should be deleted.

Thank you very much for spending your time for me and I'm extremely sorry for the OS crash and BOD happened in your system. That didn't really happened in my system. I didn't know why that happened in your pc. Any way, I'm extremely sorry for that.I really didn't cared much about back cover and frame back side separation distance since they didn't show any bad outputs in the rendered image or video output. I will fix that.

But I have a doubt, I was trying to bake the diffuse map with direct and indirect lighting unchecked. You said that baking diffuse output for a model which is having
multiple types of shaders(Diffuse, Glossy, Emission, Transparency) all at the same time is not preferable. Why is that so? Even if there are multiple types of shaders, it will bake only the diffuse shader right. I've already done those and haven't experience any issues. Could you please tell me more about those or direct me to a link that can help me that?

One last thing. In the end you said that the large back piece that is hidden inside UV map space is a wastage and must be removed. Was that about the back cover?

The reason I said to avoid baking lots of pass types all at once is because you're new to baking textures and you're having problems.  It's best to start with simple pieces and work your way up to complexity.  I have no links to prove this to you, just 10+years of experience tells me so.  https://sketchfab.com/models/6ddbdeba6e154b2abb1103650032f20c

For now I recommend separating the model into pieces by materials.  You have 9 materials so pull each component out one at a time by selecting according to material in the materials tab and move that piece to it's own layer.  Now just bake each piece to the image texture to get a feel for how it looks.  I did this and everything worked.  I just didn't bother to assemble all the pieces at the end.  Try it.  You're good at modeling, you should pick this up quickly if you break it into manageable pieces so that errors can be easy isolated and fixed.  Baking/UVing is difficult, a lot can go wrong.

Yeah that worked


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I want to animate a whole bunch of birds
I’ve made a whole bunch of birds and I want to animate them.
The easiest way that I can think to do is put stage one down, next frame replace it with the second one and so on so forth.
But how would I do this? How do I go to the next frame and replace it without messing up frame number one?

Or if someone could just point me to a tutorial? That would be great

Maybe try particle system? Boids sounds like the correct mode. It is not very clear what you are trying to achieve, maybe you should do some research about it.

I have no clue what that means

source: Stack Exchange

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

sort: votes


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Renaming Animation Channels with a Script
I changed my armature bones and it screwed up my animation. I'd like to traverse ALL my animations and channels and change a specific channel name to the updated bone channel name. How can I do this with their API I cant find docs for traversing the animations.

This should do the trick. Obviously, you will have to fill in the complete dictionary of bone name mappings.
import bpy

d = {"oldname1":"newname1","oldname2":"newname2", }
for action in bpy.data.actions:
    #these so called action groups are the bones, ie one group contains all fcurves of one bone
    for group in action.groups:
        if group.name in d:
            oldname = group.name
            group.name = d[oldname]
            for fcurve in group.channels:
                fcurve.data_path = fcurve.data_path.replace(oldname, d[oldname])

You are a life saver. And here I was thinking the stack exchange was subpar.

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


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how to get character textures to flow?
I'm very new to the whole material/texturing pipeline, and i've been having trouble figuring out how people get their materials to follow the form nicely. Like if I have a material for a scale texture, how do i get it to follow the flow of the creature's body?
I know I could go in and use a texture brush to sculpt in the details on multiresolution, then bake that into a normalmap, but is that really the best way to go about this?

https://blender.stackexchange.com/questions/23173/how-do-texture-coordinates-work and https://blender.stackexchange.com/questions/38651/what-does-unwrapping-a-model-do-and-why-is-it-important

The key is how you UV Unwrap your mesh. A good way to check Your UV maps is to apply a checker pattern to your mesh. There are many videos and tutorials out there that are great for becoming better at the anatomy of Unwrapping, but the best way to learn is to practice yourself. Starting with simple objects like a can, and moving on to more complex objects like a creature.

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


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is there a way to mirror traditionally painted textures?
So I modeled a sort of dragon character, unwrapped it and blocked in colors with texture paint.

I exported the UVs and blocked texture to one of my art softwares. I kinda hate blender's texture painting for when you want something with clean lines.
My question is, if I make edits in an image editing software, is there a way for the texture to be mirrored on the x axis once i re-import it? It would be difficult to get both sides exactly the same in an image editing program without straight up duplicating and mirroring every single piece by hand. That takes a while and it feels like something that would have a solution in blender. anyway, any answers would help.

It's not clear. Your UV coordinates seem to be not overlapping, so if painting on image you will be able to paint on both sides. If you want sides to have mirrored paint you could use mirrored UV map where mirrored islands overlap with original ones.

I think you should look at doing your painting in Blender and then 'fixing' it in your external editor. Look at two things to help : The Curves panel, choose a brush curve that gets you a better paint stroke along with the stroke type set to Curve where you can set the points with ctrl-click and then enter key to stroke along the path.
For Symmetry, your UVs don't need to be lying on top of each other in Blender since you can toggle the symmetry axis there to determine where your paint is mirrored despite your UV island arrangement.
If you must use the external paint then you will need to make your object's UV islands to coincide right and left on top of each other, but I think you might be better off trying the method I laid out here.

if you really want both sides of the character to be exactly mirrored versions of each other you can just use the mirror modifier and paint on one side of your mesh only. By default the mirror modifier will just lay the UVs of the mirror-generated side of the mesh exactly on top of the original ones. That means that you only ever have to worry about painting one side and the other one will appear as an exactly mirrored version.
This means though that you won't be able to implement asymmetrical elements down the line.

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


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shrinkwrap won't give me nice creases
i've got a sculpt i'm retopologizing and i'm having issues with the area where the legs connect to the body. The shrinkwrap doesn't seem to go into the creases. is there anything i can do to fix this?

I know it ain't fun to hear, but professional artists almost never use tools like shrinkwrap. They usually don't give a clean result, and its generally better to do the task manually. If I were you, I would just create a sphere primitive and extrude your way down the arm.

Especially since you are retopologizing, shrinkwrap isn't for you because it will give you bad vertex distribution and no intelligent placement for areas that need a higher polycount

Shrinkwrap is ok for repotology and pros do use it as a tool, not a complete solution. You can get verts to follow the surface closer by subdividing and physically placing the source vertices deeper into  crevices.


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How to get gradient material to work with rig?
I've got a lil character i'm making that uses some gradient materials, but I don't know how to make the gradient move with the deformations.

as you can see, the gradient doesn't move with the deformations which makes sense with how it's setup, but I want to find a way to change that. I was hoping to avoid having to UV map because It's pretty hard for me to get such clean gradients with a texture.
here's my node setup:

UV is the best way. Try to use gradient tool in the texture paint mode (Fill brush with 'Use gradient' checked). It works nice on the texture, and on the model as well.


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Animation loop issue with Bezier and snapping issue with linear
So I have an idle animation of my skeleton 160 frames each rot/pos is 40 frames apart, and I am trying to get it to smoothly go between each set of frames and also loop smoothly. I have my first and last frames set to the same values, my start at 1 and my end at 159. Bezier is causing my animation to flow smoothly between my first and last frame, but causes it to pauses when it loops back from frame 159 to frame 1, while Linear causes it to loop perfectly from frame 159 to frame 1, but causes my frames in between the beginning and last frame to snap very quickly which makes it look jerky.
Any help is greatly appreciated!

This can be effected in the Graph editor. Use Bezier throughout but at the end and start frames (160 & 1), swing those keyframe handles so that frame160 doesn't slow down and frame 1 kicks off without a pause.  i.e. remove the curvature at the last (160) and also at the starting frame (1).  Loop the animation through 1 to 159 as before.

I dont understand what you mean by stringing keyframe handles, could you explain more or link me a video or another forum post if you know of one?

Looping animation back to 1st frame - Smooth transition :
The gif animation is doing what you're seeking, using Bezier throughout, but straightening the curves in the graph editor at the first and last frames. (where it crosses the red line at the left)

How it's done -
Select the cube (moving object) and go to the Graph Editor.
In there select the first keyframe for the axis required (red is X, green is Y) and use the keyframe handles to straighten out the starting curve so the object kicks off in linear fashion, i.e. without accelleration.

Go to that same axis' last keyframe and do the same.
Ensure that the exit curve (at last keyframe) is at much the same angle as the first's.   That will ensure the object doesn't twitch, when the timeline cursor loops back to frame 1.
(in the example animation at top, that's where the thin cube crosses the red line at the left)
Do the same with the other axis'.  In this example the Z axis wasn't used.


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Weight Painting Dragging pieces of mesh with value of 0
so I am trying to put a bone on a rope on the well that I made so that I can make it swing back and forth, but I cant seem to get my weight painting to work.

My rope has a value of 0 all out except for at the end of the that I want to move with my bone
When I rotate my bone it grabs that whole edge and moves it with the bone for some reason
I've checked and all my vertices have a 0 weight except for the area that I want to move, even if I pull the weight value from 10 to 5 on the end it still gets the same result when rotating the bone
I've also tried deleting the bone completely and re adding it but that didn't help.

Perhaps try to select all the bugged part of the mesh in Edit mode, and in the menu on the right of the Vertex Groups list, choose Delete From All Groups.

That didn't work sadly, I ended up removing the part of the mesh that I wanted to move with the bone, adding the bone, and re adding it and that worked for me.


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Node connections have weird black borders?
So the other day my cat walked across my keyboard and now all the connection lines for my nodes in the node editor have weird black areas around them . . . not sure what it does and would like to be able to return it to normal lol.
Any input is accepted.
blender 2.69

Any reason you're still on such an old version of Blender?

ya lol. its my daughters pc and its running xp still cuz for the life of me i cant get 7 to run stable on it. . . . i run 2.78 but still its a something i have yet to see or read about and because of that i have no idea what it does or how to make it go away haha ( still a noob if you couldnt tell) :)

Running WinXP at this moment is rather irresponsible. Better install one of the flavours of Ubuntu Linux if the hardware doesn't support a newer Windows, it'll run Blender just fine.

i started teaching my kid about the use of pc's when she was 4 . . . she is 9 now and getting pretty good at it but im not sure im ready to set her up on a linux build or a dual boot yet lol . . . especially because they are also trying to teach her how to operate mac os x at school

like dont get me wrong i get what your saying and soon with any luck ill have her on a better pc but for now it would be easiest to just figure out what the cat did to cause the black borders around the noodles. So far i havent been able to determine what it is even doing. Like its not stopping things from rendering or anything like that . . . . i just want to know what its purpose is and how to turn it on and off lol. im still pretty noob at this lol and i was hopping to avoid hours and hours of reading documentation to find the solution :)

Usually I would recommend upgrading your video drivers and Blender, but since that's not an option, maybe try the Interface tab of the User Preferences?


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Circle more round
We can see there a sharp edges (its not ideal circle).
How to make this custom circle more round?

Follow these steps:

Select the circle (or Mesh) which you want to make round.
Go to modifiers tab, Apply Subdivision modifier to the mesh.

(You can increase subdivision counts according your needs. Increasing Count To higher value than 2, Cause blender respond slower)(Recommended=2)
You will get the more round circle but it will increase vertices count..


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Text to Mesh, Change Back Mode?
I Recently made an intro. I separated the text letters and converted to mesh so that I could do these effects. Now everyone says I'm unable to go back to editable text mode. Is there an add-on to get back from mesh to text? Or any other way to transfer all key frames to a text object so I could get it back somehow?

No. There is no way to change mesh back to text.

"It's actually stupid that blender haven't fixed this from the start!" this is what makes this question opinion-based and potentionally unanswerable. "some really good art could be unavailable to edit back!" just create a copy prior to converting text to mesh. Or study Animation Nodes addon and create it dynamically


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How to connect two cylinders with a third one connecting the two?
I am trying to make a sketch of an optical setup.
Currently I am using long cylinders as beampaths. (if anyone has better suggestions, those are also very welcome)
My problem is that I want to connect my beampaths, such that each one of them makes a full path (just like the light in the real setup) which seems to be astonishingly hard in blender. I would like to simply enter start and end point of the line, then create a cylinder along that, but could not yet find a way to do something like that and rather have to work with Euler angles.
The image shows the setup I have this far. Between the two lenses I want to show the four beams from the left being focused and exiting the lens setup, connecting to the right four paths.

If I understand you correctly, you are looking for a curve with a bevel object.
When you are in objectmode, i would recommend to start with a bezier curve. go to the curve properties and there you can give it "thinckness" with a so called bevel object(has to be also a curve object).

I assume that you need a circle for the cilindrical shape of the ray.
you can also change the diameter by adjusting the size of the bevel object.

for getting sharp angles in your curve you also have to change the handle type of the curves vertices to  vector (Shortcut: V).
therefore you have to be in editmode:

If you want to connect multiple objects together, select every object you want to join and then press CTRL+J.
BUT
It is not possible to "weld" multiple curves together, because a curve vertex can only connect to two curve segments.

The only way is, to convert the curves to meshes (ALT + C)
and then you are able to connect the parts via mesh modeling.

Thank you very much for the answer, this seems to be already very close to what I need.
However, I am stuck at adding the Bevel Object.
When I click inside of the text box, I can type Bevel Object, but nothing happens. How do I get this to work?
Another question is, how do I connect multiple of these curves?
Or can I just keep expending it section by section?

@mitit100 First problem: You need to create a circular curve and call it Bevel Object, then you can select Bevel Object in that textbox. (Or you could call it asdfdsjkhlkhlkjn and select asdfdsjkhlkhlkjn in the textbox. Or Circle would be a more obvious name)

@mitit100 I edited my answer according to your second question.

@monatsend
Thanks for the edit.
How do you make the curves join together nicely? When I hit Ctrl+J, they do get grouped together in the outline, but their edges stay somewhat disconnected and they do not get patched together at all if I do not move them together already. Is there some snapping involved?
immibis, thanks, this worked. Is there a way to upvote comments?

yes that's the difficulty. you have to model it by hand. but you can try to merge it with the boolean operation( https://www.youtube.com/watch?v=WxMwa0njGSM )

I figured it out with your help.
The solution I found was

Create Bezier curve
Add the Bezier circle to give it thickness
Subdivide the Bezier curve into as many sections as I need
Adjust the positions of the divider as needed/calculated

The subdivision is found in Edit Mode while highlighting TWO segments that are adjacent to each other -> Curve -> Segment -> Subdivide
This will add one more segment into the curve, giving one more adjustable fixpoint in the modeling. Repeat as needed. Only downside is if you want to extend your curve, you need to move the first/last fixpoint and put the new subdivider to the place where it was before.
Picture shows the final result.

highlighting TWO ?vertices? You have to select the segments, which you want to subdivide. Many more adjacent vertices' segments can be subdivided during the same operation.


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Move one pose bone to the location of another in the same armature
Could someone help me get out of the starting blocks I suspect I'm making this harder than it needs to be.
with python
Lets say in pose mode I have bone A at location (0.00,0.00,2.00) world space equivalent local space is (0.00,0.00,0.00)
I want to move it to the same location as bone B in the same local space.  Lets say bone B is at (0.00,1.00,0.00) world space local space is (0.00,0.00,0.00)
I've been going around in circles with various matrix calculations and Just can't get my head around it just yet.
The local space for bone A in this example should end up as (0.00,-2.00,-1.00)
I found this in relation to a different question which has a great answer and explains how the matrices are set up clearly but I can't seem to apply it to my situation.
How to convert coordinates from vertex to world-space?
thanks!
Mark

Related  Also look at the addons/rigify/rig_ui_template.py Visual Helper functions.

thanks so much, that got me on the right lines, will post code snippet

Many thanks @batFINGER that got me heading in the correct direction, I now need to spend a few hours understanding why it works :) I modified the code from the example you linked to.
I've updated with extra comments and modified the code after I did some research to get my head around it, happy to take feed back I've misinterpreted anything
does not seem to need any additional calculations if it's a child of another bone but would be interested I'f I missed something there.
Mark
In my example from my question

bone y+1 is located at (0,1,0) in pose space but the local location
is (0,0,0) as that is where the bone is in edit mode.
bone z+2 is located at (0,0,2) in pose space but it's local location
is (0,0,0) as that is where the bone is in edit mode.
the armature object is at (0,0,0) world space

The translation (where the bone actually is in pose space) is stored in the first 3 rows of the 4th column of the 4x4 matrix reading down X,Y Z the other numbers define rotation and scale which I'm not looking at here.
so for y+1 the default matrix is
(1.0000, 0.0000,  0.0000, 0.0000)
(0.0000, 0.0000, -1.0000, 1.0000)
(0.0000, 1.0000,  0.0000, 0.0000)
(0.0000, 0.0000,  0.0000, 1.0000)

for z+2 the default matrix is
(1.0000, 0.0000,  0.0000, 0.0000)
(0.0000, 0.0000, -1.0000, 0.0000)
(0.0000, 1.0000,  0.0000, 2.0000)
(0.0000, 0.0000,  0.0000, 1.0000)

the armature world matrix is
(1.0000, 0.0000, 0.0000, 0.0000)
(0.0000, 1.0000, 0.0000, 0.0000)
(0.0000, 0.0000, 1.0000, 0.0000)
(0.0000, 0.0000, 0.0000, 1.0000)

The armature world matrix is important if you want to translate locations between world and local space as if it's not (0,0,0) then it needs to be added as an offset (and removed as an offset (inverted) as required.)
import bpy

#assume armature is active and has 2 bones in it called
# "y+1" and "z+2" at different locations
armature = bpy.context.active_object
y1_bone = armature.pose.bones["y+1"]
z2_bone = armature.pose.bones["z+2"]

#y1 is the bone we want to use as the target,
#multiplying 2 matrices is a dot multiplication i.e. each column gets multiplied with each row then added together
#it's not simple scalar with one value with just multiply the whole matrix so the below will produce a matrix
#that will add the armature world location to the y1 location

#if you want to place or align stuff outside the armature in world space then the following two pieces of code will
#take the armature world space offset into account but it's over kill for just moving about in the same local space

#this gets the world space
y1_world_matrix = armature.matrix_world * y1_bone.matrix

#this copies the default and calculates the local space
matrix = armature.matrix_world.inverted() * y1_world_matrix

#the above two would make more sense if say you were trying to place an
#empty in world space at the pose bones location.
z2_bone.matrix.translation = matrix.translation

#if it's just in local space you can remove the armature offset calculations
#above and just assign the translation
#of the target bone to the bone you want to move
#e.g. the below and the local space coordinates will update accordingly.

z2_bone.matrix.translation = y1_bone.matrix.translation


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How do I produce a final rendered image using Cycles in Blender 2.8 in the Image Editor, as before?
There doesn't seem to be a button that when pressed would produce a render in the image editor, to the specifications made in the rendering options.

This is still possible. You can configure it in Render > Display Mode > Image Editor


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Is there anyway to use a shape or mesh as a mask?
I saw a tutorial on making a "sky box" or "Sky dome" and I was wondering if this can be done in any other shape like a humanoid mesh.
Alternatively: im trying to figure out out how to put a nebula/space or Galaxy in a human shape so when it moves , so does the image like a parallax effect or a window.
My other best guess would be using some kind of projection mapping?

Could you show some example? Seems like simple Texture Coordinates > Camera should do the trick, but I'm not sure what you exactly want to achieve.

Welcome to the site! I agree with @cgslav, it is hard to understand what you're asking. Could you maybe explain a little further or maybe even add images of the desired effect? That way people will know exactly what you want and if their answer answers your question, so they won't hesitate posting it and you will get more high quality answers.

A sky box is just what is visible beyond everything else, that is what the world background material is for. For your nebula, if you use a texture coordinates node and connect the camera or window output, the texture will stay still as you nebula moves.


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Can metallic car paint be exported in GLTF?
I'm trying to export a car model with red metallic paint as a GLTF model. A diffused red metallic with a high gloss clear. It appears that with GLTF it's either one or the other?
I can get somewhat of a metallic paint look by sharpening up the roughness of the metallic, but then it looks more like anodized metal than car paint.
Is this a limitation of the GLTF format or does anyone know of a workaround? Thanks.

(Answer updated 2020-05-13)
You're looking for a feature called clear coat.  There are three relevant inputs on the Principled BSDF shader node, called "Clearcoat," "Clearcoat Roughness," and "Clearcoat Normal."
These three settings will export to glTF files beginning with Blender version 2.83 (still in Beta as I write this).  It will import from glTF files beginning in Blender 2.90 (currently in Alpha).
Clear coat is not part of the glTF 2.0 core specification, but it was added in a glTF extension called KHR_materials_clearcoat.  Not all glTF viewers can display clear coat yet, but some of the major ones have released stable versions that can, including ThreeJS, BabylonJS, and Filament.  The gltf-test project has a test of clear coat with a summary of some frameworks that support it.


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Project an environment texture to a ground plane that updates with the camera FOV
I'm trying to project my scenes environment texture to a ground plane so that when viewed from the camera it matches the environment, but also updates when the camera is moved or rotated.
Like a projection mapping of sorts that's linked to the environment texture and the cameras FOV. I think it might have something to do with the vector transform node, but I'm struggling to get it to match up with the environment and update as necessary.
The image below is my node setup and also shows the environment being projected onto the ground plane. Thanks in advance.

Camera/UV projection modifier should work out of the box with your setup. Alternatively: Camera projection without generating UV's?


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No transparancy when rendering
I imported a video file with a greenscreen backround.  I was able to remove the green and acheive transparency. However when I render I still see the green screen.  Even though I don't see it in the compositor.  Help?

Do you expect others to guess how you set up your nodes and render settings? Please edit your question and add more information and images that show what you did.

Maybe in the Properties panel > Output > Post Processing, enable the Compositing option?

https://ibb.co/p4BrJR3.    There is a photo.  And I did have compositor checked in post proccessing @moonboots

but you haven't plugged your Keying node in the Composite node (which is the Compositor's Output)


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Transfer Animation from timeline to action editor
All of my animations are on the main timeline.   How do I make single actions/stash them.   I can't copy and paste frames in there so what can I do.

not sure what's your problem, if you open the Dopesheet and switch it to Action Editor mode, you'll see that your object's action has already a name, so you can close, duplicate, create a new one, etc... If you click on the arrow icon (Only Includes Channels...) you'll only see what's the action for the selected object(s)

I have 1 single action.  That action is over 5,000 key frames.   How am I supposed to take parts of that one big action and maker more smaller actions out of it.

For example you can copy the part you want, create a new action, and paste, or duplicate your big action and delete the parts you don't want...

I tried to copy the frames I wanted and paste them but it wasn't pasting anything in there.   Got Facebook?  Can I show you on video chat?  Or can you meet me in blender animation chat and I'll show you on video what im doing?

I've just realized that if you want to copy paste from an action to another you need to create at least one keyframe in the new action. You can link a video in your question if you want


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BGE animation property?
Is it possible to give an animation frame a property so to say?   I want to hold down a button and play the beginning or first half of my animation.  Call it frame 1-12.   A flipper animation.  IF you hold it down until frame 12 I want frame 12 to trigger the next 12 frames of the 24 frame animation.    Essentially If you dont hold the attack button long enough it wont play the full attack.  Just the wind up frames... Then revert/flipper back to the beginning.      What is a way to accomplish this?

I think I may have an answer for that- but it requires an xbox 360 gamepad. Check out this game if you have a 360 controller...


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Red line from Shader node to Color Ramp

I was following a tutorial in order to learn nodes for 2.8. When this line turned red and made the entire thing pink (missing textures). Does anyone know how to prevent this?

The mix Shader node doesn't make sense there, hence the red line. 'Mix RGB' node might work for your case

In the latest builds of Blender 2.8, the node editor has been enhanced to highlight some links in red to indicate that they are invalid connections. In this particular case, you're using a Mix Shader node to mix colors - you should instead be using a MixRGB node for this; the Mix Shader should only be used to connect to Green sockets.
In general, you should only connect 'like for like' - ie, green to green, grey to grey, yellow to yellow, etc. There are exceptions to this and Blender can automatically convert between some types - eg, connecting a Scalar (Grey) socket to a Color (Yellow) will automatically generate a greyscale color. Similary, connecting a Color (Yellow) to a Scalar (Grey) will average all the color channels together as (r+g+b)/3 to use the result.
However, Green represents a shader output - which is more than just a surface color and cannot be automatically converted - so connecting one of those to another color is not valid. Previously Blender would allow this without warning and simply produce an invalid result, but the Node Editor has now been enhanced to warn of such invalid connections by highlighting the link in Red.

On The Red Line Put The "Shader To RGB" Node (Eevee Exclusive)

Do note though that RGB has to be converted to shader after ColorRamp since the latter outputs color. It is much more logical to cut Mix shader from where it is and paste it into the place between ColorRamp and Material Output in this case


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Overlaying 2 transparent images on another texture
I'm new to the exchange, I am going around in circles trying to get my nodes setup correctly in blender cycles. The basic setup is that I have a brick texture, which I want to overlay/mix 2 grunge textures with transparency in. However, although everything appears fine in material view, which is how I want things to appear, when rendered everything is black. I've eliminated lighting as a problem. I've read article after article on using transparent images in cycles as well as watched several youtube videos, but still my setup seems to be wrong. Maybe what I am trying to do isn't possible.
I've uploaded the blend file to my onedrive, so you can take a look at it, bare in mind I am no artist and this is a simple model for uploading to a virtual world, so it's nothing fancy and I'm still learning, so my geometry might be a little rubbish too. lol
If someone could set things up for me, I would appreciate it, then I can learn from what I see.
The blend file can be found here: https://pkamc-my.sharepoint.com/:u:/g/personal/atlockey_myoffice365_site/EQcTn5iMnZdHpNzOjup10XoBXa1WnJrgr1239vGw4osPpw?e=9KHroh
Cheers
Andy

It doesn't look like your texture images have been packed in with the file. Your environmental images have, but your model texture images are not there. File > External Data > Pack images with .blend. This option embeds your texture files into your Blend file.

Sorry for the delay, for some reason they weren't packing, they should be now, touch wood, I'm not having much luck today lol

Hi. Please add images to your question so that it isn't isn't fully dependant on downloading your file.

Now there's a prob with downloading the file :) But I had a look at the first file. You have two major probs with your node trees. First, always try and match output colors with input colors. You're trying to use Mix SHADER nodes (green I/O) as inputs for COLOR nodes (yellow I/O). Second, you need a shader as your last node before the Output. Bluntly speaking, shaders 'shade' polys with the required surface qualities: diffuse, transparency, bump, gloss, emission, etc. Everything else is about determining the color or pattern of the shader.

@ OroborosNZ. Sorry about that when I overwrote the file in my onedrive, the sharing permissions and link changed, I have an updated link below. So from what you are saying, the problem most likely lies at my use of the RGB mix shaders, I've added a shader as my last node before the output, that works for showing the brick texture in render mode, so that's progress, it's just the transparent images that need sorting.
https://pkamc-my.sharepoint.com/:u:/g/personal/atlockey_myoffice365_site/ET6FLNzVOqdChLupvWr-CEwBiZ_Zowd-t_Xxv6bvdYKeOQ?e=a8tV54

@RayMairlot I don't see an option to attach pictures, I'm new to this site, so bare with me.

My apologies but it seems every time I save changes to the file, the link changes on onedrive, another issue I will have to look into, I have saved another copy on my desktop to play with, the new link is:
https://pkamc-my.sharepoint.com/:u:/g/personal/atlockey_myoffice365_site/EVptkCGUmCJNm7D-DxOXWm0BWHC6Wo8HpVYAoOBNiWc3_w?e=yW5TWU

Ok I got it sorted, I have placed a version of the correct one up on my onedrive, so people can compare, but basically I didn't know you could take your colour to more than one input, so by doing that, I got my yellow dots going to the RGB mix properly. Whether I still need all the nodes, I don't know, I dare not touch anything else, now it is working. I appreciate your help Oroboros.
New file In case someone else is searching for this problem can be found here:
https://pkamc-my.sharepoint.com/:u:/g/personal/atlockey_myoffice365_site/ETHpldoGuvJBrGA406pr9b8B-EbPN0LzJ1Y_qGjoSPSf9w?e=QubmdE

You're mixing up shaders with texture compositing operations.
The shaders are the ones with the green sockets, and you should never connect other colours to the green sockets or vice-versa.
The yellow and gray sockets are used for colours and values respectively. In practice it means you'll use the yellow sockets to add colour textures to your shaders inputs, and grayscale textures (or single values) to control properties.
(that's a gross over-simplification, but it will help to have a minimum grasp of what you should/shoudn't connect to each type of socket).
With the above in mind, remember that you can mix and combine textures BEFORE connecting them to a shader. So in this case you should use mixRGB nodes to combine them and plug the result to the shader.
In your example of brick texture and grunge textures it would be just matter of blending the first grunge texture over the brick texture (using a mix node if the grunge one has alpha channel will do, but you could also use a different blending and connect the second texture's alpha to the Fac input to drive the mix).
Once you did that, the output of that mix will be textures 1 and 2 blended, so you only need to add another mix and blend the third texture over.
That will be your "combined" texture that you will plug to the colour socket of your shader (most likely a diffuse shader).
You can add further work to your shader if you need some glossiness or other surface properties to your material, but that's basically the procedure of combining textures.
*) Note that mixing two shaders (one transparent and an emissive/reflective one) to create a material with transparency based on a texture's alpha is a completely different procedure.

Right basically the mistake I was making was as pointed out by Oroboros, I was plugging the outputs from the mix shader of my transparency setup into the colour inputs of my RGB Mix Shader, so it was a green dot to a yellow dot. (as per first picture)

So I unplugged that setup and ran the colour output from my Texture node directly to colour input of the RGB Mix shader as well as leaving it going to my transparency setup and additionally ran a second alpha output up to the RGB mix shader's factor input. (As per picture 2)

It seems like a lot of spaghetti for a simple task, so I can't be sure it's all needed, however it works, so I'm leaving well alone.


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I added some legs to a Blender model and now the bones do not move the mesh, what did I do?
So this is the first time I've done this in Blender opposed to using PMX Editor. I wanted a model to have legs and a skirt instead of the jeans she originally had so I added them and removed the bones that came with the legs. I have deleted the extra vertex groups it created and now none of the bones work.
How do I go about fixing this? I have included the Blender file. Any help would be absolutely amazing.

Try turning manipulate center points off.

Answered by @batFINGER.

Try turning manipulate center points off. – batFINGER


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Creating custom render passes
Working with the appleseed render engine and we are working on integrating AOV’s.  I’d like to import those AOV’s into custom render passes but I’m having trouble decoding how to create those passes as there are three different options in the RenderEngine types relating to it but no clear explanation on when they should be used (update_passes, register_passes and add_pass)

See my Q/A here: https://blender.stackexchange.com/questions/100791/how-to-use-the-new-render-pass-api-for-an-external-renderer

Beautiful. I didn’t find that thread but it looks good.

Works awesome BYOB.  One question though: is there any way that you know of to add a pass but not have it appear as an option in the image editor?  I'm interested in having a behind-the-scenes render pass that I can use for special cases but it should not be accessible to a user.

I don't think that's possible if you want to write it into a render result.
However you can always write your data into an array or a similar buffer and handle it your way.


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Stereoscopic camera export
Working on integrating the stereoscopic camera into a render addon (appleseed).  Thanks to Brecht I figured out how to set the proper view and retrieve the X offset for the camera lens when off-axis mode is used, but I can't figure out how to get the matrices for the two views.  None of the camera matrices (world, local) change when the view is changed in the render engine.  Is there a matrix that I'm missing or do I have to do the math manually (which would suck)?

Thanks to Brecht (and some bug fixes to Blender), here's the workflow for using stereoscopic rendering in a render addon:
There are three main commands needed, all are part of the RenderEngine:
active_view_set: this is used to set the view to one of the stereo cameras.  Use the same name as the view, i.e. if the view is called 'left' the command would be active_view_set(view='left')
The camera matrix of this view is retrieved by using camera_model_matrix.
If you use the offset orientation then there is also an x-axis lens shift in one or both cameras.  That is retrieved with camera_shift_x.
For feeding render results into Blender, you need to add the view name to the begin_results call.  Blender expects the render engine to manage the logic of rendering the image twice from the different cameras and feeding the results to the correct view in the render results.
Note: Due to a bug that was fixed after the release of Blender 2.79b, camera_model_matrix only works correctly if a recent buildbot build of Blender is used.

Good addition byob


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Huion Q11k Click not rigistred in 3d view
I just got a Huion Q11K. It works perfectly except inside the blender 3d view ( The main reason I got it).
When I try to sculpt the clicks sometimes register and sometimes don't.
If I move around and sculpt it works then it stops. When I press ctrl it doesn't substract unless I pan around and click again.
I think it might be related to this thread Graphics Tablet not working only in 3D View which is closed.

Question is hardware related, perhaps also related to configuration on yout local machine. there are other support channels for these kind of questions. Not sure why this question needs to be reopened. Also not clear if the action that is posted in the closed question did work or not (disable Ink).

The tablet works fine with every other software. The problem only effects blender 3d View. Even blender menus work fine. Maybe there is an option in blender that might fix that. This is my question.

It wasn't a problem with blender as everyone said. But Blender was the only program that got affected with this.
When setting the pencil buttons in Huion, I changed the switch brush to middle click so I can move around. It turns out it didn't change it but added it so the button does both. I removed switch brush and it works as a charm.
I hope someone finds this useful. And close this thread :-)


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Why the same animation in Dope Sheet acts diferent with other armatures that are equally structured
I created an animation in Dope Sheet, which works perfectly on the armature I was working on, then I tried to put the same animation on the other armatures (identical to the initial one), the final result is all bones moving randomly, some bones playing the animation in one side, other bones are moving completely at the opposite way... totally a mess.
As you can apreciate on the photo, some of the legs are crazy! (I've only animated the middle legs).

Was the orientation (rotation) of the bones identical as well ?

Did you get this sorted?


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The area where the mesh should be displayed is missing
I'm absolutely brand new to Blender, just started today (so sorry if this is the stupidest question ever but google isn't helping any)
The area where the model is displayed went missing
I don't know what happened, and ctrl z doesn't help
Basically it just shows the UV map area and nothing else

On bottom this is the timeline. Just above the uv map area. On bottom left of it there is a button looking like an image. Click on it and choose '3D View'.

What did you do? Were you UV texturing these toruses? People, be specific!

@Lukasz-40sth in this case it's really quite obvious that he switched to the image editor and wants to get back to the 3D view.

On bottom this is the timeline. Just above the uv map area. On bottom
  left of it there is a button looking like an image. Click on it and
  choose '3D View'. – lemon

You can see what lemon described in the image below.


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Is there a move topological brush in Blender?
I can't find a way to change falloff to use the distance on the topology rather than the absolute distance.
It is very difficult to sculpt things like fingers. When I grab one finger it automatically moves the others.
zBrush does have this brush, but I'd really prefer to stay in blender.
Is there some option/addon/workaround to this?

Pablo Dobarro is currently working on plenty new features and improvements for sculpting. I'm not familiar with the zBrush behavior, but it could be a feature that will be included in one of the next Blender versions.

There is not counter part to topological falloff with the sculpt tools AFAIK. There is a topological option in the move, scale, rotate tools when you enable Proportional Editing called Connected Only.
If you need to use the sculpt tools, use masking or hide parts of the mesh.

I was looking for a similar functionality.  A workaround for this is masking off the area that you want unaffected.  This is also useful for areas like the lips.

While there doesn't seem to be a good option for this within Blender itself, I've been very pleased with using the GoB Blender addon that allows you to easily cross-edit any mesh within Zbrush and Blender at the same time.


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Baking onto different uvmaps
Let's say I have a object that has a uvmap called uv1 and has a color,roughness,bump etc applied in cycles through image textures with texture coordinate set to uv using uv1 and the image textures are meant for uv1, is it possible to transfer the colour,bump etc to another image which uses another uvmap uv2.
Note: it would be easy for me to do so if the object was textured using procedurals all I have to do is bake the textures using uv2, but I hand painted details onto the object using uv1

Cycles bakes with the active (selected) UV map and to the selected Image node.


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Problem with Baking Normals in blender

From the image you can see the render looks great but every time I try to bake normals it looks yellowish like the image, can someone tell me what am doing wrong,or if there is another way to bake bump as normals in blender,thanks and also there are no doubles or inverted normals or overlapping meshes thanks

Can't see anything wrong with the normal map. What kind of result were you expecting?

Less yellow more blue

High frequency details result in less blue color. If the normal texture works correctly when applied as normal map, then it's absolutely fine.

Seriously I had no idea thanks

It works thanks should have applied it first


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Baking Normals in blender

When I try to bake normals using the settings in the image the normal bakes with weird colors and the object is unwrapped no doubles or inverted normals, can someone tell me what am doing wrong,thanks.

what does your object look like rendered with that displacement? Also plugging a vector output into a value input like displacement is not likely to produce good results. Before you even start baking you need to check that what you are actually trying to bake looks sensible.

Thanks seems I was oblivious about that but is there anyway better way to bake normals in blender


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Mapping of texture changes when using subsurf modifier
I'm a beginnner with Blender and I try to train myself watching videos tuts, but today I'm confronted with a small problem that I can't find the answer.
As the pictures describe better than the words, I made a small picture describing my problem.
My problem is that I can't get a UV Map with the right size and the correct deformation. I tried several things but I can't do it. Could you please help me to fix my problem and especially to understand how to do it.


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Why are there dark patches in my rendered drop diamonds?

Does anybody know why there are dark patches in the corners of the pear shaped diamonds in my renders?
I have attached the node set up of the diamonds (which i followed from a tutorial) incase there is anything wrong in there, and also the lighting setup for the same reasons.
I have tried spinning the ring and no matter which angle it is rendered at there is still darker patches, and i have also used a boolean to make sure there are no intersecting pieces of 'metal mesh' on the 'diamond mesh'.
Is it just a lack of light behind the claws and the shadows that are cast causing the diamond to reflect the darkness or are there other problems?

What are your Render > Light Parhs > Max Bounces, and > Transparency set to? One of the first things to check is if you're running out of ray before a light-source/color is reached.

It would be easy if you uploaded the blend file, or drawed where are the dark patches, because I can't see them in your image, but I simply think that the "Dark Patches" you mentioned are simply reflections from the area around your scene that has not a background. Think about it, the left and right portion of your scene doesn't have anything for the ring to reflect, if you are not using a HDRI, which I think you're not, then the dark patches are simply reflections of empty areas.
As for the shader you have, I don't know why you have 4 different colored glass shaders adding on top of each other, might be something to do with that, it should be easier to reacreate the same material with a Principled BSDF shader.
Also your top image is a rendered one, in which engine you are rendering? Cycles or Internal? That might change things as well, your rendering options like bounces can affect that kind of thing too, that's why it's much easier if you uploaded your blend file.
But I hope this answer helped you,

I am using a HDRI, but there are black sections in the HDRI which may be the problem, also, the glass shaders are to replicate the different colour refractions that diamonds produce to increase realism. I am rendering in the blender cycles engine & finally i wasnt aware of the ability to upload the blender file as i am new to BSE but i appreciate you taking your time to help!


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Is there any way to limit reflection on a specific part of a mesh
I have horrible reflections of the inside of the ring when i render, i was just wondering if there is a way to hide these reflections, maybe adding an invisible plane that does not show on the render but does on the reflections? It just makes the render look horrible.

Select the faces inside the ring and give them their own material. You can then assign them a material that doesn't reflect (or has diffuse reflections) and render that. If you really need to fake a reflective material inside the ring that can't see the rest of the ring....
Take that same new inner material and Set it to holdout. Do a render. Switch the material back to the same as before and do another render, but set the number of bounces in this new render to 1 or otherwise disable reflections. You can even hide the whole rest of the ring for the second render.  Then composite the two images together.


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How can i merge these two meshes without non manifold edges?
I am trying to merge these two patterns into one, for a ring project i am working on, but whenever I merge them, i end up with tons of non manifold edges. When i merge them to a seperate object and then merge them, it occasionally works. I have tried recalculating the normals first but it just doesn't seem to work. Does anybody have a short answer as of why, or a quick workaround for merging two objects without ending up with non manifold edges? I use Booltron union to merge them normally, and it works for 99% of my other projects without issues.
Any help appreciated.
Thank you.

I'm thinking that due to the complex overlapping geometry non-manifold faces are basically inevitable, but I could be wrong. Would parenting one pattern to the other work for your purposes, or do they need to be part of the same mesh?

There are several ways you can go about doing this. If the two patterns must be part of one mesh for your purposes, the use the second two options, but if they don't need to be merged into one, then first option will probably work better in the long run and is nondestructive.
Parenting the Meshes
First, if you don't need the objects to actually be a part of the same mesh, you can parent one to the other. This will allow them to be transformed, keyframed, and animated as one object, but won't cause the problems of non-manifold geometry. This approach may also make texturing easier. You can parent them by selecting one mesh, hold shift and select the other. Then press ctrl+P and set parent to object.
Merge and Manual Editing
If the objects need to be part of one mesh, you can join them by selecting one mesh, hold shift and select the other. Then press ⌘+J to join the meshes. Once complete, you can go into Edit mode, ensure you have Vertex Select enables, and go to Select > Select All by Trait > Non Manifold. This will identify any Non Manifold geometry in you mesh and you may be able to fix it by hand.
Merge and Remeshing
You can also try remeshing the object once merged. Go to the Sculpting window and locate the Remesh option near the top. You can adjust the size of the new faces from here (based on Voxel Size). The smaller the Voxel Size, the more detailed the new mesh will be, but it will also take longer and create and object with many more vertices. This approach may also cause unwanted geometry between the two objects.
As mentioned previously, the first approach will most likely yield the most desirable results.


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Blender Crashing regularly
Whenever I do not press a key on blender 2.82a for 10-20 seconds and then go to do something, it keeps crashing like this;

Am i doing something wrong or am i likely to have something turned on/off which i shouldn't?
Thanks

Can you post your crash log?
https://docs.blender.org/manual/es/dev/troubleshooting/crash.html#crash-log

Where would i find that? It isn't actually crashing, as i can scroll over the affected areas and they will return to normal, so its kind of like a temporary crash, ive never experienced it before in 3/4 years of using blender until i downloaded 2.82a

It seems an hardware problem. With updated drivers, I would do a stress test to check if the hardware is working as expected. If everything is fine, you can try to reinstall blender in a new folder and Load Factory settings (then remember to reactivate GPU if available).

also for these type of errors please always include what OS you are running and what Graphicscard you have

I have an nvidia 1070 gtx and i am currently using windows 10


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Pixelated error on select faces during Render
I have a low poly model and I can't figure out what is doing this. It's not a reversed normal and I removed duplicate vertexes so....?  These faces were the most recent adds to the model buy adding vertexes and creating new faces. there are a little bit darker than the others when viewed as solid.
thanks

I'm not sure but I think its either 2 faces/vertices in the same spot or your faces are backwards that you can fix with ctrl+N

Ctrl +N does not fix it it. Removing duplicates does not fix it.

Running only the "remove duplicated" operator is not enough to get rid of all the the possible overlapping causes. Examine the interested area and see what is causing the overlap.

So it was definitely a duplicate face, but the bad face had some strange properties. I had to delete all the bad faces and start over. I created the issue again by subdividing the edge and creating a new face with the new vertex. Still don't know why.


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How do I recreate these Bouncy hair Physics?
Reference Video
https://www.youtube.com/watch?v=FqBmxRmI5OM
How Can I recreate these Hair Physics?
From what I can tell, the hair can:
Jiggle
Bounce opposite directions (<--- (head) ---->)
^ Kinda Like Anime Physics.

Reference File: https://drive.google.com/open?id=10SZJ1oqHpUndhmQSrd_IFhEescsaYOgp
Includes: Animation Test File / Model (Rig)

If you can post the end file, and give me an replied Tutorial here, on: how to recreate it. That'll be Really appreciate...!
Looking forward to reading your responses!

First guess is using MikuMikuDance. There is a blender mmd_tools addon. You could either use soft body or clothe sim on a hair mesh to simulate the hair, the top verts are pinned to follow the head, the rest is simulated.

@sambler, I use the MMD_Tools Addon, I don't want to revert to MMD, I used the addon to create the Reference file. Can you perform the Softbody / cloth sim on the hair, because whenever I try to use either, the results are awful...

If it´s not necessary to work with the same hierarchy than the original MMD, I´d recommend doing the cloth sim on the hair directly.


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Change texture during animation
I wanted to know if there was a way to change the texture of an object using keyframes during an animation. Thank you.

I'm using Cycles.


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Skip Specific Dupliframes?
I am using dupliframes to copy an object along a path but is there any way to skip a specific frames? They don’t repeat so I can’t use “On” and “Off.” And I can’t use the array and curve modifier because it distorts the mesh.

You could consider using the animation nodes addon. It is very easy to create the described sort of effect.

How could I use the animation node addon? Sorry I have never used it.

It is a node based system, which can procedurally generate many things. It will however take you approx 2-10 hours to learn it.


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Fading out particle system from one side
I am trying to animate a part of a forest being cleared and being replaced by a building. I was wondering how I would animate the tree particles in the area fading out in transparency from the top of the image to the bottom, with the bottom trees fading out last. The area around the clearing is a river. I have created a separate particle system with only the trees that I want to disappear. This particle system is hidden in the  picture. I was looking into using the distance from an empty on the top side with no success yet. Thank you.

I apologize if I did not explain the problem thoroughly. I found a rather simple way to achieve the effect. I first made a gradient and mapped it to a plane.

By setting the particles to use the uv map of the plane and checking "From Instancer", I used the gradient to determine the factor used for transparency.

By animating the location of the gradient I achieved this sweeping effect.

In the shader nodes for the particle material consider using the particle info node .  The particle info node is only compatible with the Cycles renderer and not Eevee.
Particles have a lifetime and a current age.  The math nodes use this info to change a number for each particle from 1 to 0 which is used to change the transparency.
Of course the math nodes can be changed to suit your particular needs.  Gain and Bias.  Offset and Scale.
I am not sure if you need one or two of the candidate answers.

The idea behind these shaders is to delay fading until a certain age of particles are reached. Offset.  Untested set of nodes.  Image above.

Animations from a carefully produced gradient image using techniques described below.  Note the frame numbers to explain the fast progression.

Animation of a swirl blob with some unfortunate consequences of a bowl cut aesthetics.  Some problems are difficult to see and perhaps later we can pinpoint the culprit.  All animations are a single particles system driven by a texture.

Mesh on left which has a UV Map.  Particles start emitting in the darkest region first of the texture first. Note the frame number. The yellow arrow arrow on the upper right indicates to use the image as general time / emission time.  The yellow arrow on the lower right shows a texture associated with the particle system. Image above.  Click to see larger image. You can take more time with your image.
Please know you may need two textures.  One for restricting placement and another idicating emission time.  Like a boolean [and].

Showing the UV Map. Image above.

The particle emission pattern as expected from the texture. Note the frame number. Image above.
Textures can control the birth time/emission time of particles.  So the particles can appear in a particular spatial arrangement, flowing across a mesh.  Texture information can be attached in the Particle settings. Next more info is specified in the texture panel for the object.
You may also change materials alpha with keyframes for your rendering if that suits you. So both spatial arrangement and color can change or alpha transparency can change.
Image sequences can also be played in reverse in the Blender Video Sequence Editor .. VSE.
Please show a texture or multiple textures with a gradient from black to gray to  white in the areas of interest.  Black areas would produce particles first followed by gray and white areas would be last. Brightness based, You can use your preferred image editor.  Blender or GIMP perhaps.

A more carefully created gradient texture.  The green is intended to indicate background.  The particles follow the pattern from corner to center, in a video render.


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Shading changes between eevee and cycles
Okay, I'm having some shading issues when I render in cycles which I don't have when I render in Eevee is there a way to fix the issues in cycles, I would prefer to use cycles for my renders, Thanks.
The image with the blue circle is eevee the shading is flat, but in cycles the one with red there are some shading issues.

Hello, is it shade flat? Maybe share this part of your object?

Does this part of the object render this way if rendered in isolation, or if you rotate any HDR lighting? The 'issue' could be the result of genuine indirect lighting, not represented in your EEVEE setup.  Do you have some kind of (possibly unnecessary) AO influencing the cycles render?

It's a game asset, that part is not flat shaded but It has a normal map.

I do have an AO map added to the basecolor in cycles, let me check if disabling it changes anything, but I would need the AO map since some detail are not real geometry but normal details and their shadows scan only be represented through the normal map.


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How can my add-on extension access its own manifest
In Blender versions prior to 4.2 I was able to access the version of my add-on in the register function through bl_info.
In Blender 4.2 this is no longer available as the bl_info variable gets deleted by addon_utils.py.
The information about the add-on is now stored in blender_manifest.toml. How can my add-on access this information?
(PS. I could parse the toml myself, but i am hoping the api provides a way to access the info)


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Rendering in GPU and CPU in different instances at once
I am currently rendering an animation in cycles and I have another animation to render after it is finished. I am rendering the current animation with my GPU and was wondering if I could render the other animation using my CPU in another instance. Would this be efficient? Thank you.

Yes, mixing CUP and GPU rendering on two instances should be faster if you have enough memory to fit two instances of the rendering job. Just make sure you set the CPU rendering instance to a lower priority (using the task manager on Windows, or nice with Linux) so that it doesn't take any CPU resources away from the GPU instance. Otherwise the GPU instance might be starved for instruction from the CPU and cause a slowdown.
With Blender 2.79a, a built-in mixed CPU/GPU rendering mode is also available. Just need to enable it from the User Preferences:

It appears that the feature didn't make it in the official 2.79a release, though.


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Wave-Modified Collision Object Not Changing
Please see a gif pic of my situation:

http://gph.is/2EwjmKs
The gif image shows that the ball responds only to the mesh-shaped collision object that is present at frame 1 in the first half of the gif picture.
In the second half, you can see the ball exhibits the same behavior without a moving mesh that's in the same shape as frame 1 in the first half of the gif pic.
How can I elicit a dynamically changing collision object for my wavy plane?

Enable 'Deforming' in the Rigid Body Collisions panel should do it.

lol Thanks a million, Mike Pan. Your suggestion is perfectly applicable to my answer quest and has relieved me of worry. Thanks again, you rock.


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Orbit a planet partially around a sun
New file.  Two objects:

Sun is centered at cursor over XY intersection.

Planet orbiting that sun is displaced a few units away along the Y axis.

Task:
Keep sun centered in place over cursor in the center of the XY intersection.  But orbit the planet 120° toward the other side of the sun.

hello, could you please show a drawing of what you want to do?

Add an Empty (plain axes) at the center of the XY intersection and parent the Planet to the Empty. Then, rotate the empty to make the planet "orbit".

That did it.  Thanks.


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Where are .exr files listed in Properties dropdowns in Blender?
city.exr, courtyard.exr, forest.exr, interior.exr, night.exr, studio.exr, sunrise.exr, sunset.exr are shipped with Blender 2.92 and courtyard.exr wants to load by default into a simple refraction construct--it's visible here in the area below the UV skydome I set on top of the XY plane:

Before I discovered these samples in the Shading top-screen tab, I think I encountered the list of same .exr names elsewhere in the side screen control panels (but I don't remember where).
Therefore my question is where are these .exr files in Properties dropdowns and elsewhere in Blender?

This probably isn't exactly what you're looking for, but the files themselves are located in the blender folder at .../2.92/datafiles/studiolights/world. You can add them as any image or environment texture. Also, you said you're already aware of the selection that appears when you click the sphere in the top right (under where it says "scene world"), correct?

Thanks for replying, yeah I'm aware of the spheres accessed from clicking under where it says "scene world" but I vaguely recall seeing them lined up one above the other in text string format in a drop-down too, elsewhere in the Blender UI.  Problem: The .exr is showing up as artifact in the object refraction (underneath inside the sky dome).  Visible in attached pic, above, in thread.  One's coral-colored, the other (should it be there at all?) is painted with the forest.exr shading.  Trying to get rid of it.


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Create an animated dotted line
I want to make this kind of animated dotted line:
https://www.youtube.com/watch?v=9mFa2iI_Nn0.
I will keep the camera fixed. The only thing I want to generate is the animated dotted line between 2 points. Like the youtube tutorial I have

deleted the cube
added a big plane
added a nurbspath
added a little plane

After I have added 2 modifiers to this plane, an array (with fixed count on x axis and relative offset) and a curve (with the nurbspath like object).
The last step is generating the animation by keyframing the 1frame with
relative offset in minimum, and keyframing frame 250 with
relative offset in maximum. All is exactly like in the youtube tutorial. I have added two LocRot keyframed an yet absolutely no movement between the two keyframes has been generated.
I have added a screen of the blender file to help you.

And so, how can I generate with Blender this animated dotted line ?

The video you linked shows you how to create the dotted line in Blender.


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Restrict mouse within an area
With python script is it possible to restrict the mouse within an area, like Object->Transform->Move menu does in 3d viewport? When this op is started, user can't move the mouse cursor out of the 3d viewport.

Why? What is your overall goal?

Related https://blender.stackexchange.com/questions/91900/how-to-get-the-mouse-position-outside-of-the-window-on-modal-operator  AFAIK there is no option in blender python to control the mouse location (get sure, not set).. Would require some third party tool perhaps.

@Leander I have a script that starts drawing on first mouse click and finishes on second click (just like move op , which finishes after second click). So the user should not be able to move the cursor out of the viewport between the two clicks.

Why is the drawing position/"brush" not always under the mouse position? Is it similiar to the moving op with Shift? You know that a modal operator will capture the mouse position in other regions/areas as well?

@batFINGER Thank you for the pointer. I wish this was possible :(

(I apologize for being so forward. Most of the time, hijacking the mouse is a design fault with better alternatives.)

If the user can only draw in the region with the mouse, they are not going to move it outside of said region.

@Leander I understand it's better to not curtail user freedom as much as possible. It would be possible to draw without any restriction if the drawing were to be done with dragging the mouse (press to start, move to draw, release to finish). But unfortunately my requierment is to start drawing after the click (press+release), continue with it (move) till next click (again press+release). So between the first and second click if I allow user to click anywhere, my drawing could go haywire, if user starts a new op in the middle.

You could run a modal operator, that only exits correctly if the second/next click is in the same region. You can check the region of the 2nd click; if it is outside of the region, you can abort thr operation.

This would also prevent other operations from running simultaneously.

@Leander Yes, maybe. But then there is another problem. I need to catch the mouse press event in the modal function. If I let the other operations in the queue process the press event after me (by returning PASS_THROUGH) then there are some undesirable results like objects in the viewport moving with the mouse press (which was for drawing). And if I dont let the other ops to process the press event (by returning RUNNING_MODAL) then users can't use any buttons on the header or toolbar.

@Leander So my idea was restrict the user within the drawable area, and return RUNNING_MODAL on press. The mouse will be freed up only after user cancels the operation.

Thank you for your explanation, I have the feeling that this is already much closer to the actual problem your facing. In your description, the user can only exit the drawing space (to execute other commands) if he cancels the operation. Inverse, you could design it, that leaving the drawing space cancels the operation, right?

User can potentially leave the drawing space quite often. And I can't cancel the op immediately as user leaves the space (even when he is not drawing since the drawing op is active.)


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Transform Along Z in 'View' Transform Orientation
If the transform orientation is set to 'View', no transform along Z axis should possible, since the view is always 2d. But in perspective view, the transformation along Z is still possible (which makes sense because it's perspective view).

Any idea, how this transformation can be calculated using python (transform along X and Y can be calculated using region_3d.view_matrix, but this fails with Z)?

What do you mean by 'fails with Z' (and not x y) using view_matrix?

After applying the view_matrix the X and Y values are correct but Z does not change, i. e. it changes in global space in such a way that there is no movement along Z in view.

I'm guessing here: these view matrices should be orthogonal (I think) so try calculating the Z axis as the cross product between the X and Y.


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Orthographic projection matrix of view
The region_3d.view_matrix of an area returns the perpective projection matrix. How to get the orthographic projection matrix for the same view?

The api docs say the perspective_matrix is window_matrix * view_matrix. The window_matrix and perspective_matrix change when switching between persp and ortho. view_matrix only changes when you pan/rot in the viewport.

@sambler I was trying to transform the coordinates into view_matrix to get the projection of a point on plane (https://blender.stackexchange.com/questions/150645/projection-of-point-on-plane). That problem is solved. But thank you for this piece of information.


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Voronoi Node Fracture Module for 2.8?
Does anyone know if progress is being made on the Voronoi Fracture module for 2.8? Thanks.

I'm voting to close this question as off-topic because it will attract speculation about unknown development targets

Just wondering, why would this question be off topic? Seems to be about a part of Blender that is very important to some of us.

Also, I just received this answer from another source, which might be very relevant to some people who are using 2.8: It's in latest beta 2.8 build. Works fine most of the time, but may cause blender to crash, so save often.
Edit - preferences - Tick 'Cell Fracture'
Then either search it under spacebar menu or select object, go to 'Object - Quick Effects - Cell Fracture'

Since most people here are not Blender developers no one can give you an accurate answer of when or if. Even the developers probably don't know themselves, so any post here would an opinion or speculation from our part at best


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Syncing a Blender camera tracking scene to an Fspy camera match
I've been having issues orientating a tracking scene--
For a recent project, I started by doing a camera match on the first frame in Fspy, which produced an amazing result, as evidence by the sample geometry I added as a test:

However, after taking the rest of the footage through blender's camera tracking process, I'm finding it impossible to line up with the above Fspy import.
The Fspy import gave the scene a Field of View of 48.16, while the camera tracking seems to be spitting out a Field of View of around 13.5 . Is there someway I can alter the camera track to generate the 48.16 Field of view? Is there a better way to orient the scene without needing to go through Fspy? Happy to provide the Blend file/Fspy export if needed. .


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Problems constraining a non-geo-nodes object to follow a geo-nodes-modified curve
Here's my issue:
I have a complex curve object. I used geometry nodes' "resample curve" node to evenly distribute its vertices so my car objects (with no geometry nodes) can follow it at a linear speed. However, this creates a new issue -- the "follow path constraint" i have on my cars appear to evaluate before the geometry nodes modifier, so they're still just following the original curve without the resampling.
I know I can add a geometry node network to the cars with a "sample curve" node to make them follow the new resampled curve, but unfortunately these cars have several materials and children that I would need to recreate in geo nodes.
Is there a simple way to solve this problem that I'm overlooking?


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How to scale up a random texture on a flat plain without duplicating
I have transferred a heightmap similar to wrinkles on a surface and now I want to scale it up to a bigger surface area. However, I don't want to replicate the texture but I want to reproduce it randomly on a surface so I won't lose its randomness (I don't want to replicate similar tiles to the initial image). Is there any way to do that?

how much bigger? can you show examples of what you have and what you want?

Now, I have the structure on a small square plain which is applied from a heightmap. The structure is wrinkle-like and random. So, I want to scale it up on a bigger plain and I want to reproduce the structure on the bigger plain, but not replicating it as similar tiles.

The reason I asked about the size was that if it is 5 times bigger or more then you will need to look at coding a solution or excepting tiles. Smaller and you can try stretching the existing texture or creating a custom brushes and painting the patterns on. It would also be helpful to see your current height map. Please add it to your question.

Yes, I understand. I didn't have an image at the moment but as soon as I have access to it, I will upload the heightmap. Your answer was already helpful, thanks.


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What version of Blender to use with 10.14.6 Mojave
Version 2.79b of Blender won't open in on my Mac. Which one should I be useing for 10.14.6 Mojave?

"Blender 2.79 runs on all systems that support OpenGL 2.1 and above, with recent graphics drivers. For macOS, version 10.9 and later are supported." So says blender.org. This could be an OpenGL/drivers issue.

Thanks for the info. I can run 2.79 on my Mac at home (it can only run El Capitan) but my system at work which runs Mojave can only run 2.80. Since I am new to Blender, I started with 2.79 over the weekend. But, when I started to work on 2.8 everything was different. So I tried to switch to 2.79 and it would not run. So I guess I am stuck with running two different systems. Thanks again.

As of today (July 11, 2019), 10.14.6 is a beta OS version. Blender 2.79b runs fine on my iMac with 10.14.5. If you are a beta tester for 10.14.6, I would recommend submitting a bug report both to Apple and to the Blender team.

Thanks very much for your input. I miss read the OS X number. I am running 10.14.5 not .6. I think that since Blender is going to become 2.8 very soon, I will just "start" there hope it runs on my El Capitan system at home. Thanks again for your help.


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(2.8) Do you need to apply subdivision surface mod before UV unwrapping for texture painting?
I am relatively new to Blender, using 2.8, and just made a model using the subdivision surface modifier. I'm onto the texture painting phase, but whenever I select all geometry in edit mode and unwrap, I get the unwrapped version without the subdivision modifier applied. I don't want this since I want to paint directly on the surface itself. Do I need to apply subdivision surface to do this, or is there a way to unwrap with the modifier already applied?

If you just unwrap it as normal, so that it unwraps the un-subdivided version of the mesh, and then start texture painting, it should work as expected.  If not, you can apply the subdivision modifier and then unwrap.


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How to remove weights on vertices (2.8)
So for some context: I uploaded a model to Mixamo to get a rig for it, and this rig works fairly well, with the only problem being that the character's tail is distorted. I would like to remove the influence of the bones on the tail, but I can't seem to do this.
I've tried two different ways, both with similar outcomes:
 - Weight painting: tried painting with weight 0 on the tail region, ended up still having the tail weight be present with weird spikes in the tail
 - Changing vertex weights in edit mode: highlighted the tail region with circle highlighting, set weights to 0, also got weird spikes in the tail and a bunch of tail vertices still had weights on them
What's the proper way to do this?


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How to add two parents to a single child object in blender?
I have a car tire and I want two different bones to control it's rotation and and turning respectively.For that I want to make the tire parent to both the bones.Please tell me the way to a two bones parent to tire.

An object can only have one parent. In the example you give, you want one wheel bone to control the wheel. This bone would be animated to rotate on its Y-axis, this bone is then parented to a steering bone that will "turn" the wheel bone, but does not directly move the wheel mesh.

This rotates the wheel but doesn't turn the wheel?

Please can you explain a bit in detail how to do it.

@VedantBhosale Two bones - one rotates the wheel as it rolls on the ground, the other steers the wheel. I have added a link to an example blend.

Thank you very much sir.

So you have connected vertical bone's head to horizontal's tail using offset in edit mode and connected horizontal bone's head to tire using the same.Am I correct?

One last question.How to connect the head of the horizontal bone to the wheel.I am unable to do that.I think I may be following wrong procedure.


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Problem with render animation in Blender 2.8 : black screen
Hello all Blender users and fans.
I am currentyl using Blender for adding animation to video editing. With Blender 2.8 I have got problem to render animation.
In the main view I have added a background picture (Add -> Image -> Background) and after a more little picture which is a simple circle (Add -> Image -> Background). I have animated this picture with keyframes to move from left to right as you can see on this picture of my screen :

When I wanted to make a render on the animation as a video first Blender when suddenly crashing. It was because of the render engine which was checked on Eevee by default :

After I have changed the render engine to Workbench or Cycles Blender doesn't crash when I render the video but this video is now rendered as a black screen ! I have changed the parameters of Workbench and the video render has changed from a black screen to a grey screen but of course my animation is not rendered.
And now I don't know what to do. I had never this problem of black screen or crash with Blender 2.79. That's why I suppose this is a problem with parameters of the Render Engine. If somebody could help me or a at least recommend me a way to find a solution I would be very very grateful.

check the compositor, is everything connected to the compositor input?


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resizing reference after giving specific dimensions
I'm trying to model a room from reference images. I know it's exact sizes,
and can change it to that in the properties. The reference picture will not change with that of course, how do i resize and place the reference in the correct way?

Answer greatly depends on what do you mean by "reference picture". Convenient way of interacting with images in viewport is with Images As Planes addon or empty images. See https://blender.stackexchange.com/questions/118/how-do-i-set-a-background-image-while-i-am-editing for info on different ways to setup reference images

try this. after resizing the mesh, note the new scale. then paste that scale into your reference image.

How about

create a plane
assign it a texture with your ref image (some UV mapping/unwrapping required to match the entire image)
Size it and use it in the background in Ortho view
repeat for front/side views with different pictures!


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Modelling a lavender flower?
I would like to model a lavender flower:

However, I don't know how to apply the blossoms properly. I guess they need to have a different rotation, need to look like they grew naturally (so in this kinda ring-like constellation) and those little leaves under the blossoms are also confusing me.
Any help?

Could you show us a screenshot of what you have so far or where you are stuck? It would be easier to help you fix it.

I didn't even start it because I don't even know where to start honestly


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Strawberry seeds
I would like to model a strawberry:

However, I don't know how to model the all around the strawberry. I already made the basic shape:

This tutorial seems like it could be good for you https://www.youtube.com/watch?v=nHt6Miij8Hw

Final:

TL;DR

Create base shape.
Select vertices where seeds should be and add them to Vertex Group.
Create seed model and use it in Particle System with Density from Vertex Group.
Bake AO map.
Use AO as a Displacement.

Semi-detailed steps:
Shape.

You can create base shape using any method you want. The important thing here is that we will use vertices for seed placement so you should have this in mind. Unwrap this mesh.
Seeds Vertex Group.

Select all vertices, than deselect the top and bottom one (if you have triangle fan there as I am). After that choose Select > Checker Deselect.
Select/deselect more vertices especially at the top and bottom to have a little bit realistic result.
Add your selection to Vertex Group and check how many you have there.
Particle system.

Add Particle System to your mesh. For Emission > Number use the number of vertices from previous step.
Use your seed model as Object and make it bigger than you will want them finally (it's for AO Bake). You can use Size > Random to have some variations.
Check Rotation for better seed placement. I've added a little bit random there.
Tweak Emitter Geometry > Normal so seeds would hover over the mesh.
AO Bake.

Create new texture for AO Map. I've used 4096x4096 32Bit.
Bake AO for this texture. Use Sampling > Samples > Render with high value to remove noise. I've used 500 samples but it is too low number.
Displacement.

Add Subdivision Modifier and set it to 4-5.
Add Displacement Modifier and use baked map as Displacement Texture. Use Texture Coordinates > UV.
Tweak Strength and Midlevel as you like.
You can also tweak texture in Texture tab using Contrast/Brightness values to get smoother/harder result and set Filter Size to 5 (check Minimum Filter Size) to get texture blurred.
Final touches.
In Particle System you can now lower seeds size and correct Emitter Geometry > Normal if needed.
You can use baked AO Map as Bump Map to emphasize indents.
You can also use Lattice along with Lattice Modifier to distort your mesh.

Blend file:

Bonus:
As a bonus, here is material setup from final render:

Jeez, that might be the most elaborate answer I ever received. Thanks a ton man!

@JuanNaym it was nice and a little bit challenging question (how to make it semi-automatic and easy to replicate), not my longest answer here though ;) I think I will edit it a bit. There is some inconsistency with indents for seeds caused by poorly unwrapped mesh. I'll need to find a better way for it.

@JuanNaym It wasn't UV Map, I didn't set origin of seed to it's center... Ctrl+Alt+Shift+C > Origin to Center of Mass (Volume). And also you can control position of seeds on Z axis by changing Velocity > Emitter Object > Z.

Well I guess it all depends on how close the camera is going to be to the strawberries. If you want it as close as the picture you provided, I am afraid there is no quick method for this. If its going to be further away from the camera I would suggest something like Alex Pensotti's answer.
But for the tedious, up close way, you could do this.
Subdivide your strawberry to about level 4 or 5 like this.

Then go to sculpt mode and choose the blob brush with subtract selected. Make the brush the size of the holes you want to create by hitting "F" and dragging mouse, then manually punch in all the holes you will need.

Then you need to make your seed, after you have it textured and shaded the way you want you will need to manually place these in all the holes you just created.

This was the best way I could think to do it. Maybe someone else has a more automatic way of doing it with particles or something.
I guess you don't have to subdivide and you could use dynotopo instead, but after adding all those holes I'm afraid your topology will be so bad that it would be better do just subdivide it, so you get nicer reflections.

The only speedup I could think of would be to select a vertex at the bottom of each 'well', duplicate and separate that selection and use dupliverts to place the seeds.

You could always find a strawberry texture that comes with a bump map or normal map and apply it to the shape. However with a normal map it won't physically be bumpy it wont effect the shape of the model with bump maps you can create the bumps where the seeds go and maybe model seeds and place them in the recessed areas created by the bump map.

This is a typical use case for geometry nodes.
Use this node setup:

result:

and with this node setup:

you can do this:

*** UPDATE ***
i just found out a more elegant way doing this:

Note: this simple solution might not look that good at the top and the bottom, but here you can use the technique from the first part of my answer to cut them off.

Sorry ... It doesn't look like a strawberry seed distribution pattern, now ... Any way to enhance technique? Thanks

For sure…needs some time. Will Update

@vklidu: i update my answer


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How to animate small water surfaces in structures?
I would like to model a so-called stormwater overflow (used within a sewage system) which is a concrete chamber in which the water level is rising during a storm inflow until the crest of an overflow weir is reached. Then, the water forms a small waterfall. I would like to have some waves on the water surface and one should see the water "falling down" at the overflow. It should look like this:

The use of the FluidSimulator of course would be straightforward, but it did not work properly in some first tests and was also very time-consuming. To complicate it a bit, the weir should be movable, going down while the water is overflowing, so there will be changing geometry.
So I ask whether there would be some way to "fake" the water. Ocean modifier plus some additional modifiers?
Greetings from Germany, Tschöbbel

Welcome to Blender.SE. This seems, as you already pointed out, a job for the fluid simulator. If you don't want to use it, try to describe which kind of effects you may be allowed to give up. Also a quick scketch of the animation would be useful to clealy understand the situation.

Final:

You can fake it pretty easily with creative UV Mapping and animating Texture location. I've used Noise Texture for it as a Bump for Principled BSDF.
Let's break it down.
Mesh:
It's simple Plane with one edge Beveled. Nothing to add here.

Material:
We need to add material first, it will be easier during UV Mapping.
Again, nothing to fancy here.

Animating.
X value in Mapping node will be animated - in this example keyframes are on frame 1 with value 0 and on frame 60 with value 1. In your case axis could be different, also bigger difference between values will give faster animation.
After adding keyframes you should go to Dope Sheet editor, select both frames from X axis and choose Key > Interpolation Mode > Linear.
UV Mapping:
Go to Edit Mode, Select All and U > Unwrap.

Now changing X axis value in Mapping node should give as something like this (I'm using Node Wrangler to be able to see Color Ramp node output):

Go back to UV Image Editor, select faces where water should be flowing faster, enable Proportional Editing and scale them down along X axis as much as you want.

Final thoughts:
This is basic overview for the water flow. You should also add some Particle system for the splashing water and maybe some foam texture. I think those should be another questions otherwise this one could become to big/tutorial like answer. Or just search trough the web, there are plenty tutorials about this.

Wow! This is exactly the effect I would li

Sorry, I fight with some issues of my smartphone, maybe something was double.    Wow! Dear Luke, this is exactly the effect I would like to obtain. Thank you very much for your very detailed answer! I will try that out within the next days.  -  Greetings, Tschöbbel

@Tschöbbel I will also try to experiment with foam texture and particles and maybe add this as a simple overview with blend file included.

I just tried your proposal and I was successful at the first try! Thanks again for your good description.

After browsing through some other questions relating to "water" in this forum, I got the idea to use a procedural texture as displacement texture (UV coordinates, normal) for a highpoly water surface using the Displace modifier in order to get real geometry (no high waves, just a bit). With a simple Voronoi texture, this works well. Is there some way to animate the textures used by a Displace modifier? One idea is perhaps to make an animated bitmap as a movie? Or is there a possibility to use the output of your bump texture with animated coordinates as continuously varying displacement map?


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Repairing a Mirror Modifier centre-line non-manifold edges (2.8)
So I have made a fairly simple shape (I'm new to blender) that I created using the mirror modifier on the X and Z axis so I only needed to make one quarter of it and the rest was mirrored. It's something I'm wanting to 3D print, so I had to make sure it was properly structured (my previous attempt had appeared in the slicer as... a complete mess.)
Everything works fine, everything is accurate. I use the 3D toolbox to check for errors, and with the mirror modifier still on the queue there's 0 non-manifolds. As soon as I apply the modifier, it changes to 40 non manifolds.
Ok that's fine, it seems to be where the mirrored objects meet. I had Merge selected on the mirror options, but it seems to do nothing. Whatever, no problem. The solution is to Remove Doubles, right? (Going from previous help topics on stack)
2.8 doesn't have Remove Doubles.
Ok so the new version of remove doubles is merge by distance. Select all the non-manifold vertices, merge by distance. Removes 0 vertices. OK maybe increase the distance a little? Nope.
It only removes vertices when I hit 5mm, which happens to be the next row of edges (which it promptly gobbles up). So as far as the merge by distance tool is concerned, I have no non-manifold doubled up edges/verts in the shape. But the 3D Toolkit is determined that I have 40 of them.
I could just select and delete them... but I'm not sure if that's fixing things or breaking them futher. But as this seems to be a question that hasn't been asked yet (since the update changed how things worked) I figured it was appropriate to ask it!
Hopefully someone can help.

Could be inner faces. Adding some image of what you are doing could help.

Select all vertices in your mesh and hit Alt-M.  From the drop-down, choose "By Distance".  You can also change the "distance" at the bottom-left corner of the window.  Here's a picture to show you where.

It looks to me like this is pretty much the same as the "Remove Doubles" option.  Hope this helps!
P.S.  If you have two vertices that are not at the same position, and you want them to merge to the position of a certain one of those vertices, you select the vertex that has the desired position first, then select the other and merge them, using the drop-down option "At First".  Hope that makes sense.

Sorry, you might want to re-read my description lol. Merge by distance doesn't work. It does nothing, unless I increase it past 5mm when it starts to eat up the adjacent lines. The faces down the mirror line remain.

Oh, oops!  Sorry about that.  It's kinda weird that that happens.  Could you upload your blend file?

I actually now can't, because I fixed the problem by going into mesh mode, finding the internal faces, and deleting them all manually. Which was a pain lol. I assumed that there would be a better way, but I failed to find it.

I can easily duplicate the problem - just make a shape using a mirror in 2.8. I had the 'merge' option on, which may have been the problem? I believe it merges vertices, which may explain why there was no doubles, but it fails to delete internal faces so it still ends up non-manifold. At least, that's what it seems like, but I'm no expert I may be making it all up.

Yeah, that sounds like the answer alright.  Good job figuring out the problem!

However it doesn't really solve the problem, as I'm assuming that's not the intended behaviour. Otherwise they wouldn't have removed the 'remove doubles' option. Having to do it all manually, when it used to be automatic, seems a bit of a step backwards.

I thought there weren't any doubles, just faces in the middle.  Am I wrong?

Ahh sorry I see what you mean, yes it seems that instead of having to remove doubles (which seemed to be the result pre-2.8), you are now left with internal faces instead which need to be removed. It's not too hard to do though, just something I'll have to remember as part of the process. Thanks for the help:)

yeah.  No problem.  It's just good to know that when you add a mirror modifier, you don't want faces at the middle.   Just delete them before you add the modifier.

Mirror mirrors everything including any faces along the mirror line which will become internal. Blender doesn't know if there is any intentional internal modeling or not, so it accepts everything. When using the mirror modifier, having clipping helps greatly for many things, keep vertices from accidentally crossing the mirror-line.